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Background: Scar brings great physical and mental pain to patients. Fat grafting may be a new and simple way to treat scar. This review aimed to systematically evaluate the correlation between fat grafting and scar reduction. Methods: The author searched Chinese and English literature databases such as CNKI, Wanfang Data, Cqvip, Pubmed, Web of Science, Embase, CBM, etc. for articles published in the period from 2011 to 2021 about the randomized controlled trials (RCTs) to assess the effect of fat grating on scar reduction, and then performed meta‐analysis with Review Manager 5.4. Results: A total of nine articles were included in the assessment of the effect of fat grafting on scar reduction, with meta‐analysis suggesting statistical significance (OR = 5.63, 95% CI: 3.01–10.53, p < 0.01). There was statistical significance in the difference observed between the simple fat grating group (p = 0.004) and the group of existing therapies combined with fat grafting (p < 0.0001). Conclusion: Fat grafting may be a good method for scar treatment, especially when it's combined with other therapies. Still, due to the limitations of included RCTs, more large‐scale high‐quality RCTs must be carried out before solid conclusions can be drawn. [ABSTRACT FROM AUTHOR]

Taking representative Tamarix chinensis forest in the national-level special protection zone for ocean ecology of Changyi city in Shandong province of China as the objective, this research studied how to use remote sensing technology to evaluate natural eco-environment and analyze spatiotemporal variation. In the process of constructing the index system of ecological environment effect evaluation based on RSEI (Remote Sensing Ecological Index) model, AOD (Aerosol Optical Depth), Salinity, Greenness, Wetness, Heat and Dryness, which can represent the ecological environment of the reserve, were selected as the corresponding indexes. In order to accurately obtain the value of the RSEI of the study area and to retain the information of the original indexes to the greatest extent, the SPCA (spatial principal components analysis) method was applied in this research. Finally, the RSEI was applied to evaluate the ecological and environmental effects and to analyze the spatial characteristics and spatiotemporal evolution of the study area. The results not only provide scientific evidence and technical guidance for the protection, transformation and management of the Tamarix chinensis forest in the protection zone but also push the development of the universal model of the ecological environment quality with a remote sensing evaluation index system at a regional scale. [ABSTRACT FROM AUTHOR]

Little is known about the pathophysiology of memory deficits in patients with major depressive disorder (MDD) treated with modified electroconvulsive therapy (MECT). This study examined the profiles of cytokines, the memory function, and their association in MECT-treated MDD patients. Forty first-episode, drug-free MDD patients and 40 healthy controls were recruited. MECT was started with antidepressant treatment at a stable initial dose. The Wechsler Memory Scale (WMS) and Hamilton Rating Scale for Depression 17 (HRSD-17) were used to assess the cognitive function. MDD patients were divided into the memory impairment group (WMS < 50) and the non-memory impairment group (WMS ≥ 50) based on the total WMS scores after MECT. The levels of NOD-like receptor 3 (NLRP3) inflammasome, interleukin-18 (IL-18) and nuclear factor kappa-B (NF-κB) in the serum were measured. MDD patients showed significantly higher levels of NLRP3 inflammasome, IL-18 and NF-κB than that in the controls prior to MECT, and the levels also significantly increased after MECT. In MDD patients, the serum levels of these inflammatory cytokines were negatively associated with the total WMS scores and likely contributed to the scores independently. The receiver operating characteristic curve showed that the serum levels of these inflammatory cytokines may predict the cognitive impairment risk in MDD patients receiving MECT. Abnormal levels of NLRP3 inflammasome, IL-18 and NF-κB reflecting the disturbed balance of pro-inflammatory and anti-inflammatory mechanisms likely contribute to the MECT-induced cognitive deficits in MDD patients. [ABSTRACT FROM AUTHOR]

The variability of the East Asian monsoon (EAM) during the Holocene exhibits significant regional response, and its evolution needs further discussion. A well-dated, high-resolution sea-surface temperature record based on long-chain unsaturated alkenones, grain-size data, and clay mineral assemblages from the South Yellow Sea sediment is presented to investigate the sedimentary provenance and reconstruct the EAM over the past 9.5 ka. The results show that the sediments are most likely supplied by the Huanghe. The evolution of the East Asian summer monsoon (EASM) can be divided into three periods: strong and relatively stable conditions during 9.5–7.0 ka, weakened conditions during 7.0–1.5 ka, and strengthened conditions during 1.5–0 ka. The East Asian winter monsoon (EAWM) has experienced five periods: weakened conditions during 9.5–6.7 ka, weak and relatively stable conditions during 6.7–5.6 ka, strong and relatively stable conditions during 5.6–2.6 ka, strengthened conditions during 2.6–1.5 ka, and weak and stable conditions during 1.5–0 ka. Moreover, in-phase correlation was found between the EAWM and EASM at the orbital time scale in response to orbital-driven solar insolation, but out-of-phase correlation at a centennial time scale is predominantly associated with solar activity. [ABSTRACT FROM AUTHOR]

Background: Active prevention and treatment of scars are particularly important. Several studies have used botulinum toxin type A(BTXA) to prevent postoperative scarring. The aim of this systematic review and meta‐analysis was to systematically evaluate the efficacy and safety of BTXA in preventing and treating postoperative scars. Methods: A computer‐based search was conducted for the five databases including PubMed, Cochrane Library, EMBASE, CNKI, and Wanfang up to May 22, 2019, to collect the relevant literatures on BTXA treatment of postoperative hypertrophic scars. A meta‐analysis was made with the software of Revman 5.3 based on the study endpoint of scar width, Vancouver Scar Scale (VSS), Visual Analogue Scale (VAS) scores, and patient satisfaction as well. Results: A total of 18 randomized controlled trials (RCTs) studies were included with 915 patients in all. The result showed that, compared with the control group, the scar width, VAS scores, and VSS scores of the BTXA group were significantly improved and higher patient satisfaction was achieved. Conclusion: BTXA has a certain curative effect on postoperative scar prevention and treatment without obvious side effects. [ABSTRACT FROM AUTHOR]

The continental shelf strata provide information regarding sea-level fluctuation and climate changes in the Quaternary period. A 5831.47-km-long high-resolution seismic profile and borehole core (YS01) were acquired to reconstruct the evolutionary history of the strata in South Yellow Sea (SYS) during the late Pleistocene. The strata recorded three transgression events (HI, HII, and HIII) and three stages of paleochannel development (LI, LII, and LIII). Based on the distribution, thickness, and volume of the strata formed in the three transgressions, we concluded that the scale of the three transgressions during the late Pleistocene was HIII, HI, and HII, in descending order. In addition, our data show that the Yellow River extended to the Yellow Sea Trough during the last glacial maximum. The influence of the tectonic framework on sedimentation in the SYS was completely concealed by sea-level changes and sediment supply in the late Pleistocene (~Marine Isotope Stage 5). Since then, the accommodation space, a crucial prerequisite for sedimentation, has been controlled solely by sea-level changes in the SYS. Furthermore, two "source to sink" models of the neritic shelf in the marine and terrestrial environments were established, including high sea-level and shelf-exposure models. [ABSTRACT FROM AUTHOR]

In order to investigate the distribution, development, and evolution of the strata in the South Yellow Sea Basin (SYSB), seismic and core data were analyzed. Fourteen (14) reflecting interfaces and 13 seismic units are identified, and a stratigraphic framework since 1.81 Ma B.P. is established. The deposition rate has changed since 126 ka B.P. The stratigraphic model shows that the SYSB responded to sea-level changes during the same period (126 ka B.P.), which suggests a model change of the development of regional strata. Between 1.81 Ma B.P. and 126 ka B.P, the Zhejiang-Minnan Uplift (ZMU) obstructed the intrusion of seawater into the SYSB which is the main factor responsible for the development of regional strata. While the sea-level fluctuation and fluvial material input have dominated the formation of the strata since 126 ka B.P. [ABSTRACT FROM AUTHOR]

The Niger River Delta is a prolific hydrocarbon province and a mega-delta of economic and environmental relevance. To understand patterns of its recent shoreline evolution (1923–2013) in response to the Niger River hydrology, and establish the role played by forces of Nature and Human, available topographic and satellite remote sensing data, combined with hydro-climatic (rainfall and runoff) data were analyzed. Results indicate that the entire delta coastline dramatically receded: 82% of the >400 km-long coast retreated, during the period 1950–1987; and 69% between 2007 and 2012. Prior to 1950, there was a continuation of seaward advancement along 53–74% of the delta coast. The 1950–1987 shoreline recession coincided with occurrences of two major events in the Niger River basin; these are downward trends in hydro-climatic conditions (the great droughts of the 1970s-1980s), and dam construction on the Lower Niger River at Kainji (1964–1968). The 2007–2012 event corresponded with the extensive channel dredging during 2009–2012 in the Lower Niger River from the coastal town of Warri in the south to Baro in the north. Remarkably, the largest net shoreline advancement recorded in 74% of the entire delta area occurred within a year (2012–2013), which we link to increased sediment supply to the coast caused by the ‘2012’ floods, adjudged the worst floods in the entire Niger River Basin in the last few decades. With both anthropogenic and environmental factors inducing delta evolution, only innovative river and coastal management can determine the fortune of the future coastal development of the Niger Delta. [ABSTRACT FROM AUTHOR]

A 230 Th-dated stalagmite record from Linyi, Shandong Province, provides a detailed history of the East Asian summer monsoon (EASM) in northern China during the last deglaciation. Our record reveals changes that are similar to previously published stalagmite records from the East Asian monsoon region on centennial and millennial scales, although some subtle and detail discrepancies are observed. Comparisons with other paleoclimate records show that the EASM was jointly controlled by the North Atlantic climate and low-latitude tropical processes during the last deglaciation. Ocean-atmospheric interactions, particularly sea surface temperature changes in the tropical Pacific might have contributed to the increasing trend of the EASM during the Bølling-Allerød and to the lesser weakening in the EASM during the Younger Dryas. In addition, the significantly higher growth rates of the stalagmite during the Heinrich Event 1 might have been driven by the CO 2 degassing processes. Future studies with long-term monitoring of the calcite deposition rate at this site will be needed to support our arguments on the CO 2 degassing processes. [ABSTRACT FROM AUTHOR]

River deltas, low-lying landforms that host critical economic infrastructures and diverse ecosystems as well as high concentrations of human population, are highly vulnerable to the effects of global climate change. In order to understand the wave climate, their potential changes and implication on coastline evolution for environment monitoring and sustainable management of the Niger Delta in the Gulf of Guinea, an investigation was carried out based on offshore wave statistics of an 110-year time series (1900–2010) dataset obtained from the ECMWF ERA-20C atmospheric reanalysis. Results of multivariate regression analyses indicate that interannual mean values of Hs and Tm trends tended to increase over time, especially in the western part of the delta coast, so that they are presently (1980 and 2010) up to 264 mm (300%) and 0.32 s (22%), respectively, higher than 80 years (1900–1930) ago. The maximum directions of the wave have become more westerly (southward) than southerly (westward) by up to 2° (33%) and the mean longshore sediment transport rate has increased by more than 8% over the last 80 years. The linear regression analysis for shoreline changes from 1987 to 2013 shows an erosional trend at the western part of the delta and accretional trends towards eastern part. The relationship between wave climate of the study area and atmospheric circulation using Pearson's correlation shows that the Atlantic Multidecadal Oscillation (AMO), North Atlantic Oscillation (NAO), East Atlantic pattern (EA) and El-Nino/Southern Oscillation (ENSO) Index explain significant proportion of the seasonal and annual wave variabilities compared to other indices. But it is most likely that the combination of these climatic indices acting together or separately constitutes a powerful and effective mechanism responsible for much of the variability of the offshore Niger Delta wave climate. The study concludes that changing wave climate off the Niger Delta has strong implications on the delta coastline changes. However, other processes (such as fluvial discharge variability due climatic variability and anthropogenic effect) may be acting concomitantly with changes in wave regime and associated littoral transport to influence shoreline evolution along the Niger Delta coast. [ABSTRACT FROM AUTHOR]

The Mariana Trench is located at the edge of the West Pacific Plate, with a lot of large aseismic ridges lying there. These seamounts significantly affect the trench morphology and topographic change by the continuous subduction associated with NW-directed Pacific Plate motion. In this article, the topography of the Mariana Trench is analysed by considering the free-space and Bouguer-gravity anomalies and the interaction between the seamounts and the plate boundary. All results indicate that following the movement of relatively isolated large-sized seamounts near the plate boundary to the edge of the Mariana Trench, the impact of the subducting plate on the surrounding area lessens. As a consequence, the trench becomes shallower and jumps towards the seaward edge. Furthermore, a large area of large-sized seamounts and oceanic rises will incise the subducting plate while approaching the trench axis, promote the subduction processes and increase the trench bathymetries. Shallower bathymetries at the middle section of the Mariana Trench, the discontinuous trench axes and some fickle topographic features in the front of the arc, are mostly caused by the docking or the subduction of the relatively isolated large-scale seamounts. The docking or the subduction of a large area of seamounts has certain influences on the formation of a deep-sea trench at the south section. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Earth system includes Earth's surface system and deep Earth system. This Special Issue tries to establish a link between these two systems. It contains 46 contributions on Earth system evolution of the Pacific and Indian oceans and the South China Sea. The themes cover the relationship of ocean to continent, tectonic jumping, morphotectonics in the continental margin, back-arc basin formation, formation of transform faults, subduction retreat, hot and cold subduction, actions of typhoons, plume-tail-related hydrothermal activity, sediment transportation and dynamics and others. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

It is a question whether the suspended sediment from the China continent could enter the Kuroshio Current and Pacific Ocean. Surface suspended matter (SSM) and sea surface temperature (SST) in the East China Seas from December 2009 to November 2010 has been extracted from the satellite NOAA-19 AVHRR/3. We have monitored the change of the SSM diffusion during summer half-year and winter half-year. High SSM areas occur in the inshore of the Liaodong Bay, Bohai Bay, Yellow River Delta, Shandong Peninsula, Jiangsu Coast and Yangtze Estuary, especially blooming in winter half-year. Going by our findings, the sediment provenance influences the SSM distribution, and the current system and monsoon are important factors that drive the SSM diffusion all year round. In winter half-year, the ocean colour images show that the current system is well developed. The SSMs are transported southeastward, and a part reaching the outer continental shelf is captured by the Kuroshio Current before it finally reaches the open Pacific Ocean through the Tokara Strait. Some SSMs are transported by the Yellow Sea and Tsushima Warm Current into the Yellow Sea and Japan Sea. In summer half-year, most of the SSM could not reach the continental shelf break and only little SSM could be captured by the Kuroshio Current into the open ocean. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Deltaic coasts are dynamic geomorphic systems where continuous changes occur on diverse spatial and temporal scales, and these changes constitute an important aspect of their evolution. Based on three-year satellite-derived shoreline data coupled with re-analyzed wave data and hydro-meteorological data, a comprehensive analysis of the dominant processes governing the seasonal shoreline changes along the oil-rich arcuate section of the Niger Delta, in the Nigerian Shelf of the North Atlantic Ocean has been undertaken. Shoreline analysis results show that the delta coast is characterized by predominant summer erosion and maximum winter accretion. Between 2010 and 2012, erosion dominated over accretion and a total of 9.1 km 2 deltaic land was lost to coastline erosion at an annual average erosion rate of 4.55±1.21 km 2 /yr. A greater understanding of the dominant factors responsible for the change is presented. Shoreline change interactions with cross-shore sediment exchange processes are prominent at seasonal timescale (Summer R 2 =−0.85 and Winter R 2 =0.7), and interannual timescale (R 2 =−0.93) with longshore sediment transport processes. Correlation analysis reveals a gradual degeneration of relationship between the suspended sediment flux and coastal hydrodynamics beginning from 2010 to 2012 (cross-shore transport, R=0.68, 0.36 and 0.2 for 2010, 2011 and 2012, respectively; longshore transport R=0.63, 0.44 and 0.2 for 2010, 2011 and 2012, respectively). The study concludes that the effect of fluvial sediment reduction to the delta coast due to capital dredging of the Lower Niger River channels between 2009 and 2012, and periodic fluctuations in the nearshore hydrodynamics processes caused the observed annual shoreline erosion that eventually forced the deltaic coastline toward a state of landward migration during the study period. [ABSTRACT FROM AUTHOR]

The East China Seas (ECS) is one of the world's largest continental shelf seas. Based on the combination of global sea level change and sequence stratigraphy, we systematically investigated the evolution of sedimentary system in the ECS since the last glacial maximum (LGM). We have defined the transgressive boundary layer and constructed several sedimentary models of the ECS on the sequence stratigraphy and evolution of tidal sand ridges since the LGM, and sediment “source to sink” during the high sea level. The result shows that the ECS represent a typical case for large-scale continental shelf response to the global sea level change. Three sedimentary system tracts had been formed in the ECS since the LGM. First is the lowstand system tract corresponding to the late of last glaciation and LGM (23–15.4 cal. kyr B.P.). The progressive wedge occurred along the Okinawa Trough slope and the paleo-coastal zone (PCZ) along the continental shelf edge. Second is the transgressive system tract corresponding to the last deglaciation (15.4–7 cal. kyr B.P.). A large-scale transgressive boundary layer and tidal sand ridges were formed in this stage. Third is the highstand system tract corresponding to the high sea level since 7 cal. kyr B.P. The eddy mud, coastal current mud, present tidal sand ridge, delta, tidal flat and beach have been accumulating since then. The global sea level change after LGM can be divided into seven phases, of which four rapidly rising phases (RRP, I, II, III, IV) and three slowly rising phases (SRP, I, II, III) are distinguished. The tidal sand ridges were formed in the SRP and transgressive boundary layer in the RRP. The tidal sand ridges can be divided into three types including radicalized, channel and emanative. The modern circulation current system of the ECS had been built in the end of the last deglaciation. The effect of sediment “source to sink” in the ECS is closely correlative to the current system driven by the interaction of the East Asian monsoon and Kuroshio. The major sediment source is from the river discharge of the Huanghe and Changjiang River, and coastal resuspension. The muddy sediment in the eddy and coastal current, which cover the tidal sand ridges and transgressive boundary layer, is a major sediment sink in the modern ECS. [ABSTRACT FROM AUTHOR]

Previous studies carried out in the East China Sea (ECS) mud area focused on long-term environmental changes in sedimentary records during the Holocene, especially during the mid-Holocene high-stand water levels period. These results indicate that sensitive grain size groups can be used as a sedimentary proxy to reconstruct the evolution of the East Asian Winter Monsoon (EAWM). The studies have been carried out mainly in the northern and middle portions of the Zhejiang-Fujian coastal mud, however, similar research in the southern portion and the comparison between sedimentary proxy and modern measured data of EAWM are lacking. In this paper, we focused on a sedimentary record of the past 100 years with an enhanced resolution of 1.8 years. Investigations of the southern end of the Zhejiang-Fujian coastal mud area were conducted on the basis of Pb chronology, grain-size analysis and chemical element analysis. The correspondence between the mean grain size (Mz) of sediment sensitive grain size and the measured EAWM was confi rmed for the fi rst time. We found that during the recent 100 years, the variation of the mean grain size of the sensitive population in the southern portion of the Zhejiang-Fujian mud was mainly controlled by the EAWM intensity changes; and not directly related to changes in the sediment discharge from Datong station of the Changjiang River (DTSD). Finally, recent changes in the content of heavy metals in study area refl ect the impact of human activities on the environment. [ABSTRACT FROM AUTHOR]

Abstract: Sedimentary environment and formation mechanism of the mud deposit in the central South Yellow Sea of China during the last 40kyr are studied based on the analysis of particle size, sediment density, chemical features, magnetic properties and AMS 14C ages of a new core YS01A together with other available core data. The results show that there exist four sedimentary sections during this 40kyr period, including two marine sections (A and C) and two terrestrial/intertidal sections (B and D). Sedimentary indexes of section D, which were formed before 40kyr, show that strong weathering and erosion occurred in this section. In contrast, sedimentary environment of section B was wetter and warmer and weathering and erosion were not as strong as in section D. Marine deposits in both sections A and C indicated the effects of sea level rise and section C was deposited when the climate was much wetter than in section A. Variations of climate and local hydrodynamics created different sediment features of two marine sections. From the estimated river discharges of the Huanghe, Changjiang and relevant Korean rivers and calculation of mud deposit volumes of section A during the past 9.7kyr, it is found that the sediment inputs from these river sources can only account for about 48% of sediments in the two mud deposits of the central and southeastern South Yellow Sea. The other main source of sediments is identified to be the seabed erosion, resuspension and redeposition from the Yellow Sea and, to a lesser extent, from the biogenesis and diagenesis. It provides a unique opportunity of understanding the formation and source of mud deposits by comparing the sedimentary properties of sections A and C in core YS01A. It is found that formation of mud deposits is not related directly to the Yellow Sea Warm Current, which only changed the sediment properties of mud deposits in section A since it formed from Holocene by bringing a large amount of organic mass and finer particles. However, cold water mass developed in this area is important as it helped to trap more and finer particles in the two marine sections. Upwelling usually occurs around 50m bathymetry which is at the juncture of two opposite water currents and has induced the thickest sediment layer. This study also confirmed that formation of the mud deposit in the central South Yellow Sea is caused mainly by the tidal currents on the continental shelves. [Copyright &y& Elsevier]

Abstract: Experiments on three types of soil (d 50=0.287, 0.057 and 0.034mm) with pipeline(D=4cm) either half buried or resting on the seabed under regular wave or combined with current actions were conducted in a large wave flume to investigate characteristics of soil responses. The pore pressures were measured through the soil depth and across the pipeline. When pipeline is present the measured pore pressures in sandy soil nearby the pipeline deviate considerably from that predicted by the poro-elasticity theory. The buried pipeline seems to provide a degree of resistance to soil liquefaction in the two finer soil seabeds. In the silt bed, a negative power relationship was found between maximum values of excess pore pressure p max and test intervals under the same wave conditions due to soil densification and dissipation of the pore pressure. In the case of wave combined with current, pore pressures in sandy soil show slightly decrease with time, whereas in silt soil, the current causes an increase in the excess pore pressure build-up, especially at the deeper depth. Comparing liquefaction depth with scour depth underneath the pipeline indicates that the occurrence of liquefaction is accompanied with larger scour depth under the same pipeline-bed configuration. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents an experimental investigation of seabed evolution behavior around a submarine pipeline and the hydrodynamic forces on the pipeline under regular waves. Unlike the previous flume tests that have largely used beds with median sands, this study focuses on fine sediments such as sandy silt and silt. The primary objective of the study was to investigate: (i) the scour process under different wave conditions and with different sediments and (ii) the influence of the bedform evolution on the hydrodynamic forces experienced by the pipeline. In terms of scour and ripple formation, four distinct regimes of the near-field bed evolution behavior are identified which are: (I) no scour, (II) scour without ripples, (III) scour with small ripples and (IV) scour with large ripples. The influence of bedform evolution on wave forces was found to vary significantly in different regimes. In regime I, the wave forces were quite stable; in regime II and III, the wave forces underwent a gradual reduction before reaching their equilibrium values at fairly early stages of the scour process; in regime IV, the wave forces were significantly affected by the migrating ripples and can be rather unsteady throughout the testing period. [Copyright &y& Elsevier]

Using the alkenone paleotemperature index U37k, a high-resolution sea surface temperature (SST) record since 3600 a BP was reconstructed from the mud area in the north of the East China Sea. Combining with the grain size distribution curve of sensitive grain size group, which may reflect the East Asia Winter Monsoon activity, the palaeoenvironmental evolution cycle throughout the late Holocene in the area was obtained. The marine environment evolution during the last 3600 years displays a five-stage trend. (1) Temperature descending period from 0.85 cal. ka BP to present. The maximum temperature decrease amplitude is 2°C. The winter monsoon intensified and 'Little Ice Age' were recorded in this period. (2) Warming period from 1.90 to 0.85 cal. ka BP. The mean temperature increase amplitude is 0.8°C.. The Sui-Tang warming period was recorded at about 0.85-1.35 cal. ka BP and a prominent cooling event was recorded at 1.4 cal. ka BP in this period. (3) Temperature descending period from 2.55 to 1.90 cal. ka BP. Temperature cooling amplitude is 0.9°C.. This period is coincident with an integrated temperature circle recorded in the Antarctic ice core, with the temperature changes from a slow cooling stage to a rapid warming stage. (4) Temperature comparatively stable with a little ascending period from 3.2 to 2.55 cal. ka BP. Temperature warming amplitude is 0.3°C.. This period is coincident with the temperature fluctuant ascending period recorded in Antarctic ice core. (5) Temperature comparatively stable with little descending period from 3.6 to 3.2 cal. ka BP. This period corresponds with the temperature fluctuant cooling period recorded in Antarctic ice core. Basically, those five periods were coincident with the Antarctic ice core record. During the global cooling stage, the SST change in the continental shelf sea can be adjusted simultaneously. [ABSTRACT FROM AUTHOR]

Abstract: Hepatitis C virus (HCV) has emerged as the major pathogen of liver disease worldwide. The mechanisms of HCV infection and interaction with a host are poorly understood. What exactly is required for efficient control of HCV infection is largely unknown. Standard treatment combining interferon-α (IFN-α) and ribavirine is effective in about 50% of the treated patients, however associated with significant toxicity and cost. Therefore, the development of new drugs or vaccines is urgently needed. An efficient vaccine against HCV infection requires induction of broad cellular and humoral immune responses against several viral proteins. We have engineered the combined vaccine candidate mT+mE1, an inclusion of multiple epitopes from HCV NS3, core (C) and E1 proteins. mT contains multiple conserved CD4+ and CD8+ T cell epitopes from HCV NS3 and C proteins. mE1 is based on eight dominant neutralizing epitopes of E1 protein from six HCV genotypes. In current study, we showed that immunization with mT+mE1 induced high titers of IgG, IgG1 and IgG2a antibodies to mE1, and high level of NS3- or C-specific CTLs. Furthermore, mT+mE1 elicited a Th1-biased immune response with secretion of high amounts of IFN-γ, compared with mT alone. Prophylactic as well as therapeutic administration of mT+mE1 in BALB/c mice led to protecting mice against SP2/0 tumor cells expressing HCV NS3 protein. These results suggested that mT+mE1 elicited strong humoral immune responses and multiple specific cellular immune responses. The vaccine candidate is now being tested in pre-clinical trials. [Copyright &y& Elsevier]

The continental shelf has experienced high-frequency transgression-regression cycles during the Quaternary, and its sediments have stored significant information on sea-level changes, climate fluctuations and regional tectonic activities. Due to the lack of extended core records and high-resolution stratigraphic chronology, the strata correlation between continental and marine basin since the Quaternary still has considerable limitations. Here, we present a high-resolution grain size and geochemical study of core CSDP-1 (~3.5 Ma) recovered from the western South Yellow Sea (SYS), China. Two sensitive components were extracted from sediments, and their contents can be used to reflect the paleo-hydrodynamic intensity and reconstruct paleoclimate change. A comprehensive analysis including lithologic characteristics of sediments and seismic data interpretation, shows that the stratum deposition at the borehole's location is relatively continuous at the orbital time-scale. The results of spectral analysis, show that the fine sensitive component it records the periodic change information of the Earth's orbital parameters (~400-, 100-, 40-, and 20-kyr), and the astronomical chronology was established successfully. The variations of sensitive components in the sediments reveals that the SYS paleoclimate has undergone four periods since the Quaternary: cold conditions during 2.58–2.49 Ma and 1.88–0.83 Ma, warm and humid conditions during 2.49–1.88 Ma and 0.83–0 Ma. Moreover, the stratum in the SYS shelf records the Middle Pleistocene climate transition (MPT). It is inferred that the MPT in the SYS is mainly manifested by the enhancement of the 100-kyr period related to the synchronous forcing of the ~400-kyr eccentricity. • An astronomical timescale since the Quaternary has been established for the South Yellow Sea for the first time. • The Mid-Pleistocene transition (MPT) is recorded by the South Yellow Sea shelf strata, which is characterized by the enhancement of 100-kyr period at ~1.0 Ma related to the synchronous forcing of 400-kyr eccentricity. • The paleoclimate in the South Yellow Sea has experienced two climate cycles from cold to warm since the Quaternary. [ABSTRACT FROM AUTHOR]

Abstract: A simple spiciness index parameter (β) is proposed which accounts for the combined contribution of temperature (T) and salinity (S) to water density. Historical monitoring data in the East China Seas (ECSs) have been processed using a formula to determine the spatial and temporal distributions of β. Based on the values of β, three key boundaries between water masses were identified, including the diluted water boundary (DWB, ) along the coast, the equilibrium line (EL, ) of water masses and the Kuroshio Margin (KM, ) on the continental shelf. Two northward points (NP1 and NP2) of the warm water mass head, two southward points (SP1 and SP2) of the diluted water mass head along the equilibrium line and one northward point (NP3) along the boundary of the warm current water are used as indicators of the extent and variability of the current system, in view of its sensitivity to the annual variation of the intensity of the warm current and the cooler coastal current that are driven, respectively, by the Kuroshio and the Eastern Asian Winter Monsoon. It was found that the evolution of the water masses in the ECSs can be divided into three phases per year, as indicated by its monthly variations. In the winter phase from October through April, the distribution of water masses is strongly influenced by the coastal current under the East Asian Winter Monsoon. In the transitional phase from May to June, the warm current intensifies whereas the coastal current weakened. In the summer phase from July through September, the water mass system is unstable in the area. The results demonstrate that the Yellow Sea coastal current (YSCC) plays an important role in the evolution of the ECSs water masses. Specifically it causes the intensification of the Min-Zhe coastal current (MZCC) and the Yellow Sea warm current (YSWC) water, and blocks the northeastward dispersion of the Taiwan warm current (TWWC) water. The result shows that the water mass of the East China Seas can be divided into four types. The first is the diluted cold water mass containing the Bohai Sea, the Yellow Sea coastal current, the Min-Zhe coastal current and the Korea coastal current (KCC) water inside the diluted water boundary. Second is the warm and salty water mass containing the Kuroshio and the Taiwan Strait warm current (TWSWC) water beyond the Kuroshio margin. Third is the mixed coastal water containing the outspread part of the YSCC and the YSWC between the diluted water boundary and equilibrium line. Fourth is the mixed warm water containing the Taiwan warm current, the Tsushima Warm Current (TSWC) and the Yellow Sea warm current between the equilibrium line and Kuroshio margin. [Copyright &y& Elsevier]

Background and Purpose: In major depressive disorder (MDD), exploration of biomarkers will be helpful in diagnosing the disorder as well as in choosing a treatment and predicting the treatment response. Currently, tRNA‐derived small ribonucleic acids (tsRNAs) have been established as promising non‐invasive biomarker candidates that may enable a more reliable diagnosis or monitoring of various diseases. Herein, we aimed to explore tsRNA expression together with functional activities in MDD development. Experimental Approach: Serum samples were obtained from patients with MDD and healthy controls, and small RNA sequencing (RNA‐Seq) was used to profile tsRNA expression. Dysregulated tsRNAs in MDD were validated by quantitative real‐time polymerase chain reaction (qRT‐PCR). The diagnostic utility of specific tsRNAs and the expression of these tsRNAs after antidepressant treatment were analysed. Key Results: In total, 38 tsRNAs were significantly differentially expressed in MDD samples relative to healthy individuals (34 up‐regulated and 4 down‐regulated). qRT‐PCR was used to validate the expression of six tsRNAs that were up‐regulated in MDD (tiRNA‐1:20‐chrM.Ser‐GCT, tiRNA‐1:33‐Gly‐GCC‐1, tRF‐1:22‐chrM.Ser‐GCT, tRF‐1:31‐Ala‐AGC‐4‐M6, tRF‐1:31‐Pro‐TGG‐2 and tRF‐1:32‐chrM.Gln‐TTG). Interestingly, serum tiRNA‐Gly‐GCC‐001 levels exhibited an area under the ROC curve of 0.844. Moreover, tiRNA‐Gly‐GCC‐001 is predicted to suppress brain‐derived neurotrophic factor (BDNF) expression. Furthermore, significant tiRNA‐Gly‐GCC‐001 down‐regulation was evident following an 8‐week treatment course and served as a promising baseline predictor of patient response to antidepressant therapy. Conclusion and Implications: Our current work reports for the first time that tiRNA‐Gly‐GCC‐001 is a promising MDD biomarker candidate that can predict patient responses to antidepressant therapy. [ABSTRACT FROM AUTHOR]

Background: Amputees suffer from symptomatic neuroma and phantom limb pain. Regenerative peripheral nerve interface (RPNI) has recently been regarded as an effective method to prevent neuroma after amputation. However, the verifications of RPNI efficacy are mostly based on subjective evaluation, lacking objective approaches. This study aims to unveil the effect of RPNI on preventing neuroma formation and provide evidence supporting the efficacy of RPNI based on ultrasound. Methods: Amputees of lower limb at Peking University People's Hospital from July 2020 to March 2022 were analyzed retrospectively. The clinical data collected consisted of general information, pathology of primary disease, history of limb-salvage treatment, amputation level of nerve, pain scales such as the Numerical Rating Scale (NRS) and the Manchester Foot Pain and Disability Index (MFPDI). Three months after amputation, the transverse diameter, anteroposterior diameter, and cross-sectional area of neuromas in stump nerves at the end of residual limbs were measured using ultrasound and compared to adjacent normal nerves. Results: Fourteen patients were enrolled in the study, including 7 in the traditional amputation group (TA group) and 7 in the RPNI group. There was no significant difference in basic information and amputation sites between the two groups. The NRS and MFPDI scores of patients in RPNI group were significantly lower than those in TA group, and decreased with the follow-up time increasing, indicating that RPNI could reduce symptomatic neuroma pain. The comparison of preoperative ultrasound and postoperative pathology showed ultrasound could reflect the size of neuroma in vivo. Independent-sample t tests indicated that the ratios of anteroposterior diameter, transverse diameter and area of the cross section of both the neuroma and adjacent normal nerve obtained via ultrasound were significantly reduced in the RPNI group. Conclusion: This study suggested that RPNI can effectively prevent the formation of symptomatic neuroma after amputation using ultrasound. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between carbohydrate antigen 125 (CA125) level and adenomyosis treatment failure (TF) after uterine artery embolization (UAE). Methods: We evaluated 224 patients with symptomatic adenomyosis who underwent UAE between January 2016 and December 2020. Improvements in dysmenorrhea and menorrhagia were assessed on the basis of symptom relief criteria. The factors associated with TF were investigated using a multivariate logistic regression model. Patients were analyzed for preoperative CA125 levels, postoperative CA125 levels, and the normalization of postoperative CA125 levels. Long‐term symptom relief and quality of life after UAE were compared between the groups. Results: During the 24‐month follow‐up, 50 patients (22.3%) experienced TF. Compared to patients in the non‐TF group, those in the TF group had significantly higher preoperative and postoperative CA125 levels (p < 0.05). Multivariate analysis revealed that failure to normalize postoperative CA125 levels was independently associated with an increased risk of TF (34.7% vs. 8.5%, p < 0.001; hazard ratio 3.953, 95% confidence interval 1.567–9.973, p = 0.004). After a 3‐month follow‐up period, patients who normalized their CA125 levels were more likely to achieve complete necrosis on magnetic resonance imaging than those who did not (82.1% vs. 56.8%, p < 0.001). Normalization of postoperative CA125 levels was significantly associated with fewer symptoms and better quality of life 12 months after UAE (p < 0.05). Conclusions: Following UAE, normalization of postoperative CA125 levels, rather than absolute values, was the strongest predictive marker of TF. [ABSTRACT FROM AUTHOR]

The scouring of seabed beneath an unburied pipeline under regular waves was investigated in a large wave flume. Sands and silts were employed for the contrast experiment and the results obtained were compared with data from literature. It was found that the standard formula of Sumer and Fredsøe was best at predicting scour depth of sands while underestimating that of sandy silts; time evolution of sand-scour depth better followed traditional exponential curves than did those of sandy silts; an empirical formula in the form of T * = 0.0066 θ − 3.034 is suggested for predicting the non-dimensional time scale of the scour process beneath pipeline in the Yellow River delta. The underestimated scour depth of silts was related to the wave-induced pore pressure responses not found in sands. It was wave-forced seepage flows that promoted the normal scour process during the initial period by exerting an uplifting seepage force on the surface particles. [ABSTRACT FROM AUTHOR]

The sediment transport of the Bohai Sea through the Bohai Strait is a key issue in coastal shelf research. Based on remote sensing data and numerical simulation results, the sediment transport from the Bohai Sea to the Yellow sea is temporally discontinuous, and the surface and bottom layers exhibit two distinct processes. Further analysis showed that discontinuities are caused by differences in stratification intensity due to wind directions. During strong northwesterly winds, suspended sediments from the Bohai Sea can be transported along the Laizhou Bay through the southern part of Bohai Strait. And northeasterly wind can strengthen the stratification by driving stronger the Yellow Sea Warm Current. Strong stratification significantly inhibited the upward diffusion of the bottom suspended sediments. Stratification with different intensities can affect the efficiency of sediment transport, which can overcome the limitations of the sediment transport mechanism in the Bohai Sea. The insights obtained in this study into the effect of stratification on sediment transport could benefit further exploration of other hydrological mechanisms in coastal shelf seas. • Sediment transport from the Bohai Sea to the Yellow sea is temporally discontinuous in winter. • Discontinuities are caused by stratification which is induced by water temperature. • Northeasterly wind can strengthen the stratification by driving stronger Yellow sea warm current. • Stratification with different intensities can affect the efficiency of sediment transport. [ABSTRACT FROM AUTHOR]

The tropical Pacific Ocean plays a significant role in climate change, and the El Niño-Southern Oscillation (ENSO) is considered to be closely related to extreme climate phenomenon worldwide. However, the evolution of the ENSO-like patterns in the tropical Pacific during the Pleistocene glacial cycles remains controversial. In this study, we present geochemical indices and a transient model simulation to explore the ENSO-like evolution during the glacial-interglacial cycles and its driving mechanisms. Our results indicate that during the interglacial periods, the Western Pacific Warm Pool (WPWP) is characterized by the modern El Niño-like conditions with relatively decreased precipitation and weakened East Asian Summer Monsoon (EASM). By contrast, the mean state of WPWP during glacial periods is more similar to the modern La Niña-like conditions, with increased precipitation and the intensified of EASM. Spectral analyses showed that the WPWP hydrodynamics were controlled by the earth's orbital parameters through their impacts on ocean circulations. Combined with published data, we find that expansion of water masses formed in the Southern Ocean would change the deep-water redox conditions, subsurface water upwelling and surface productivity in the WPWP, and ultimately influence the ENSO-like conditions through CO 2 -related Walker Circulation on glacial-interglacial cycles. • Tropical Pacific climate mean state is more similar to El Niño-like condition during interglacial periods. • ENSO-like conditions along the tropical Pacific are controlled by the earth's orbital. • Southern Ocean greatly influenced the ENSO-like conditions through the expansion of water masses. [ABSTRACT FROM AUTHOR]

Background: Amputees suffer from symptomatic neuroma and phantom limb pain. Regenerative peripheral nerve interface (RPNI) has recently been regarded as an effective method to prevent neuroma after amputation. However, the verifications of RPNI efficacy are mostly based on subjective evaluation, lacking objective approaches. This study aims to unveil the effect of RPNI on preventing neuroma formation and provide evidence supporting the efficacy of RPNI based on ultrasound. Methods: Amputees of lower limb at Peking University People's Hospital from July 2020 to March 2022 were analyzed retrospectively. The clinical data collected consisted of general information, pathology of primary disease, history of limb-salvage treatment, amputation level of nerve, pain scales such as the Numerical Rating Scale (NRS) and the Manchester Foot Pain and Disability Index (MFPDI). Three months after amputation, the transverse diameter, anteroposterior diameter, and cross-sectional area of neuromas in stump nerves at the end of residual limbs were measured using ultrasound and compared to adjacent normal nerves. Results: Fourteen patients were enrolled in the study, including 7 in the traditional amputation group (TA group) and 7 in the RPNI group. There was no significant difference in basic information and amputation sites between the two groups. The NRS and MFPDI scores of patients in RPNI group were significantly lower than those in TA group, and decreased with the follow-up time increasing, indicating that RPNI could reduce symptomatic neuroma pain. The comparison of preoperative ultrasound and postoperative pathology showed ultrasound could reflect the size of neuroma in vivo. Independent-sample t tests indicated that the ratios of anteroposterior diameter, transverse diameter and area of the cross section of both the neuroma and adjacent normal nerve obtained via ultrasound were significantly reduced in the RPNI group. Conclusion: This study suggested that RPNI can effectively prevent the formation of symptomatic neuroma after amputation using ultrasound. [ABSTRACT FROM AUTHOR]

Yellow Sea current conditions during the late Marine Isotope Stage 3 (late MIS3, 40–30 ka B.P.) highstand remain unknown. Here, environmental magnetism, geochemistry, particle size, and scanning electron microscope methods are employed to analyze core YS01A with a basal age of 40 kyr from the South Yellow Sea mud deposits. Greigite formed in marine sedimentary layers with thickness >7 m during early diagenesis. Greigite formation is related to the redox state and total organic content (TOC) availability, which are controlled, respectively, by the Yellow Sea Cold Water Mass (YSCWM) and the Yellow Sea Warm Current (YSWC). In MIS1 (7–0 ka B.P.), a strong YSWC brought greater TOC, and a strong YSCWM (thickness of 48 m) resulted in a strongly reducing low-oxygen environment. This led to massive magnetite dissolution and pyrite preservation. In late MIS3 (37–31 ka B.P.), the weak Kuroshio Current and East Asian Winter Monsoon (EAWM) resulted in a low-intensity YSWC that provided less TOC. A weak YSCWM (thickness of 35 m), caused by shallow water depths and a weak EAWM, contributed to a less reducing sedimentary environment. Thus, pyritization was interrupted and greigite was preserved. Greigite content can, thus, be used to trace the development of Yellow Sea currents. During a period of slow sea level rise at 41–37 ka B.P., minor greigite formed with most magnetite being preserved, which indicates that the environment started to become reducing. This can be interpreted as due to initial formation of a thin and weak YSCWM. During the 37–31 ka B.P. highstand, the greigite content increased, which suggests more reducing conditions related to establishment of a thicker and intensified YSCWM. In addition, the greigite content decreased progressively, which may have resulted from YSWC weakening. Our results suggest that greigite can be used as a simple tool to reflect current evolution in the Yellow Sea, which can give a better understanding of continental shelf environment change. • Greigite-bearing layers (7 m) formed in late MIS3 are detected in the Yellow Sea. • Greigite formation is controlled by the total organic content and redox state. • Its content reflects cold water mass and warm current evolution in the Yellow Sea. [ABSTRACT FROM AUTHOR]

Plume bulges were once thought to be less prone to form in an estuary with trumpet-like characteristics, such as the Pearl River Estuary (PRE), where no plume bulge has previously been detected by hydrological observations. However, based on large scale simultaneous observations, the formation dynamic of a plume bulge in the PRE during the flood-ebb tidal cycle is characterized in this paper. The influences of discharge change on the plume bulge are revealed through the different motion processes of the surface-advected plume and tidal plume. The results show that during spring tide with a weak SE wind and high river discharge (20,725 m3 s−1), a plume bulge in the PRE is produced on the south side of the Dawanshan Islands outside the estuary. Based on the standardization stratification coefficient calculation method and the salinity decomposition method, it was found that the tidal plume is the main component forming the plume bulge rather than the surface-advected plume. The 25 isohaline indicated the boundary of the PRE plume bulge. However, when the discharge was reduced by approximately 43%, no plume bulge was observed. River discharge had a considerable impact on the formation of plume bulges as higher discharge was favorable in enhancing the momentum and flux of the tidal plume in the longitudinal Lantau Channel, whereas lower discharge was favorable for the formation of a surface-advected plume flowing along the west bank. • The plume bulge was first characteristiced by multi-vessel synchronous observation in Pear River Estuary. • The generation of plume bulge is sensitive to runoff changes. • Tidal plume is more important to the formation of plume bulge than surface-advected plume. [ABSTRACT FROM AUTHOR]

As an attractive technique for measuring water vapor, the Global Navigation Satellite System (GNSS) faces additional challenges in dynamic applications such as in the open sea. We present a new method of retrieving precipitable water vapor (PWV) based on GNSS multi‐antenna precise point positioning (PPP), which uses GNSS data from multiple antennas and incorporates the constraints of known baseline vector and common tropospheric delay. The 4‐day shipborne dynamic experiment along the China coast demonstrates that the baseline vector constraint shortens the convergence time of positioning and atmospheric parameters, and also slightly improves their accuracies. The common tropospheric delay constraint helps to provide compromised, more robust, and sometimes more accurate PWV estimates. An evaluation with radiosonde‐derived PWVs shows that the combination of the two constraints achieves the best accuracy reaching 4.2 mm. This method helps to expand GNSS meteorology to the vast ocean and benefits satellite altimetry and weather forecasting. Plain Language Summary: Water vapor plays an important role in atmospheric processes ranging from global climate change to mesoscale and micro‐scale weather systems. The Global Navigation Satellite System (GNSS) is an attractive technique to measure water vapor, which has been extensively investigated for ground‐based static stations. In dynamic applications such as in the open sea, it is faced with additional challenges which may potentially degrade the performance. This study presents a new method for retrieving precipitable water vapor (PWV) based on GNSS multi‐antenna precise point positioning (PPP). It uses GNSS data from multiple antennas closely spaced and mounted on the same platform, and incorporates additional constraints of known baseline vector and common tropospheric delay. We have conducted a 4‐day shipborne dynamic experiment along the China coast and demonstrated that this method can shorten the convergence time and provide more robust and sometimes more accurate PWVs compared to conventional PPP. An accuracy level of 4.2 mm is achieved with this method for the ocean‐based dynamic experiment. This study helps to expand GNSS meteorology to challenging environments such as in the open sea, which will benefit weather forecasting and nowcasting. Key Points: A new method of retrieving precipitable water vapor (PWV) is presented based on Global Navigation Satellite System (GNSS) multi‐antenna precise point positioning (PPP)This method can shorten the convergence time and provide more robust and more accurate GNSS‐based PWVThe improved performance is helpful to expand GNSS meteorology to the vast ocean and benefits satellite altimetry and weather forecasting [ABSTRACT FROM AUTHOR]

Typhoons are commonly occurring disastrous events in the Western Pacific and have become more severe as the result of global climate changes, increasingly affecting the ocean and seafloor throughout the Western Pacific. However, studies on the influences of typhoon processes and dynamic mechanisms on the continental shelf remain rather limited because of insufficient observational data in the area. This paper uses observational records at a water depth of 110 m on the continental shelf of the East China Sea in the periods when the No. 1323 typhoon 'Fitow' and No. 1324 typhoon 'Danas' passed the East China Sea to study changes in the water temperature, salinity, current and turbidity. Observation results show that typhoon Fitow had limited effects on the measurement site because of the long distance to the centre of the typhoon, but during typhoon Danas, the measured surface current speed reached 2.95 m/s, and the turbidity of the sea water increased rapidly due to the vertical mixing of sea water. Typhoon Danas causes both near-inertial oscillations (NIOs) and diurnal currents to increase, which is considered to be the major factor that contributes to bottom water temperature changes and the suspension of bottom sediments after the passage of the typhoon. Typhoons can also cause the Kuroshio Current to shift towards the continental shelf, which may affect the Tsushima Current. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The muddy area in the centre of the South Yellow Sea (SYS) is formed and characterized by fine-grained particles since the Yellow Sea circulation system became stable before 8000 years. The distribution and thickness of the central South Yellow Sea muddy area are both updated based on the interpretation of eight high-resolution sub-bottom profiles in central SYS, 2012. The area mainly locates within 34.5°-36.5°N, 122°-124.5°E, showing thick in the north and west and thin in the south and east with a '┌' shape. The maximum thickness is up to 11 m. Meanwhile, there appears a weak deposition belt in the transition zone between the central South Yellow Sea muddy area and the slope deposit body surrounding Shandong Peninsula. In this paper, a numerical simulation under wind-driven circulation in winter is established to study the dispersal and depositional processes of the suspended sediment. Studies show that the presence of a weak-current-low-energy area by the tide is the primary factor to control the muddy area in central South Yellow Sea with similar results to previous research, but we find that the sediment is transported by the Yellow Sea Warm Current in winter. In winter, the Yellow Sea Warm Current can carry the southern sediment into here and we believe that it is the main driving force to transport sediment into the muddy area. The weak deposit band of the simulation result and measurement matched well; it is controlled by the shear front of the Yellow Sea Warm Current and the Yellow Sea Coastal Current. The shear front plays the role of a 'water barrier' to prevent the sediment carried by the Yellow Sea Coastal Current spreading directly to the muddy area and the sediment carried by the Yellow Sea Warm Current spreading to the coastal zone, so the weak deposit band arose. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Bohai Sea is a region with wintertime sea ice development and high levels of human economic activity, where sea ice has a powerful destructive effect on maritime transportation and ocean engineering. In the Bohai Sea, sediment resuspension caused by waves and currents has not previously been systematically studied during periods of ice cover. In the winter of 2009–2010, severe ice conditions with a recurrence period of 30 years occurred. In this study, wave, residual water level (RWL), residual current (RC), and suspended sediment concentration (SSC) data were collected by two seabed-based observation stations (QD12 and QDG2) for one continuous year during both ice-covered and ice-free conditions. The data were systematically compared and analyzed. Generally, the results showed that sea ice coverage had a clear suppressing effect on the significant wave height (Hs) and RWL. Hs decreased by almost 50%, and RWL decreased by 0.19 m and 0.10 m during ice-covered conditions at two stations. Sea ice coverage had a suppressing effect on the sediment resuspension due to a reduction in wave induced shear stress. The reduction of sea level and SSC was mainly reflected in the decrease of fluctuation amplitude and overall magnitude, and the suppression effect was more obvious in conditions of strong wind. The RC velocity varied during periods of ice cover in Laizhou Bay. Sea ice enhanced RC velocity during the destruction period. The RC velocity increased dramatically at station QD12 probably due to the long length of the destruction period, but decreased slightly at station QDG2 possibly due to a shorter destruction period and the blocking of Weifang Port. The enhanced RC in the destruction period carrying broken ice caused significant damage to coastal engineering projects. The suppressing effects of sea ice on Hs, RWL, and sediment resuspension, and the strengthening effects on RC velocity were both closely related to the wind speed and direction. This study reveals the effects of sea ice on local hydrodynamics and sediments, providing important reference values for the generation and disappearance of sea ice in mid- and high-latitude bays under the background of dramatic global climate change. [Display omitted] • Sea ice suppresses residual water level by blocking tides, waves and winds. • Sea ice inhibits sediment resuspension due to decrease of wave induced shear stress. • Residual currents increase during the ice destruction period. • Sea ice effects on marine dynamics are more strongly pronounced during gales. [ABSTRACT FROM AUTHOR]

The gas plume is a direct manifestation of sea cold seep and one of the most significant symbol indicators of the presence of gas hydrate reservoirs. The multibeam water column (MWC) data can be used to extract and identify the gas plume efficiently and accurately. The current research methods mostly start from the perspective of image theory, which cannot identify the three-dimensional (3D) spatial structure features of gas plumes, reducing the efficiency and accuracy of detection. Therefore, this paper proposes a method for identifying and extracting the gas plume based on an MWC point cloud model, which calculates the spatially resolved homing of MWC data and constructs a 3D point cloud model of MWC containing acoustic reflection intensity information. It first performs noise suppression of the 3D point cloud of the MWC based on the symmetric subtraction and Otsu algorithm by leveraging the noise distribution of the MWC and the reflection intensity characteristics of the gas plume. Then, it extracts the point cloud clusters containing the gas plume based on Density-Based Spatial Clustering of Applications with Noise (DBSCAN) according to the density difference between the gas plume point cloud and the background MWC point cloud and next identifies the point cloud clusters by feature matching based on fast point feature histograms (FPFHs). Finally, it extracts the gas plume point cloud set in the MWC. As evidenced by the MWC data collected from gas hydrate enrichment zones in the Gulf of Mexico, the location of gas plume extracted by this method is highly consistent with that of gas leakage points measured during the cruise. Using this method, we obtained the point cloud data set of gas plume for the first time and accurately characterized the 3D spatial morphology of the subsea gas plume, providing technical support for gas hydrate exploration, subsea gas seepage area delineation, and subsea seepage gas flux estimation. [ABSTRACT FROM AUTHOR]

An obvious shear front between the Taiwan Warm Current and the Zhe–Min (Zhejiang–Fujian) Coastal Current exists over the inner shelf of the East China Sea (ECS) in winter. Although the cross-front spread of surface water in the ECS has been reported based on satellite images, the cross-front transport of suspended particulate matter (SPM) has not been well studied. To reveal the detailed characteristics of SPM in vertical direction, in terms of different fractions, and to study its cross-front transport and mechanism, high-vertical resolution profiles of SPM concentrations observed by Laser In-Situ Scattering and Transmissometry (LISST) and derived from water samples at various levels, together with salinity and temperature, were measured in February 2007, from 34 stations in the ECS. Results showed that volume concentration (VC) of SPM finer than 280.07 µm has a good correlation with mass concentration (MC), because coarser factions were thought to be biological components. The VC was then converted to the MC of different fractions at high resolution, by reducing the influence of biological sources. Both temperature and salinity data showed an obvious front along 50 m-isobath in the bottom layer, tilting seaward toward the surface layer. Within 50 m-isobath, the MC was higher than 2 mg/L in the surface layer and 10 mg/L in the bottom layer. The SPM could be transported across the front to the sea in the bottom layer, even to the east of 100 m-isobath, where the MC of SPM was less than 1 mg/L in the surface layer and 2 mg/L in the bottom layer. The SPM across the front was mainly silt fraction with some fraction of clay. An idealized numerical model was established. Numerical experiment results showed that bottom Ekman transport produced by the northerly wind in winter is the key factor controlling cross-front transport, and strong northerly wind is responsible for its expansion. This study helps our understanding of material exchange in the coastal and shelf seas. [ABSTRACT FROM AUTHOR]

The water body's suspended concentration reflects many coastal environmental indicators, which is important for predicting ecological hazards. The modeling of any concentration in water requires solving the settling-diffusion equation (SDE), and the values of several key input parameters therein (settling velocity w s , eddy diffusivity D s , and erosion rates p (t)) directly determine the prediction performance. The time-consuming large-scale simulations would benefit if the parameter values could be estimated through available observations in the target sea area. The present work proposes a new optimization method for synchronously estimating the three parameters from limited concentration observations. First, an analytical solution to the one-dimensional vertical (1DV) SDE for suspended concentrations in an unsteady scenario is derived. Second, the near bottom suspended sediment concentration (SSC) profiles are measured with high-resolution observation. Third, the key parameters are optimized through the best fit of the measured SSC profiles and those modeled with the unsteady solution. Nonlinear least square fitting (NLSF) is introduced to judge the best fits automatically. The high-resolution concentration measurements in a specially-designed cylindrical tank experiment using the Yellow River Delta sediments test the proposed method. The method performs well in the initial period of turbulence generation when sediment resuspension is significant. It optimizes p (t) , w s , and D s with reasonable values and uniqueness of their combination. The proposed theory is a practical tool for quickly estimating key substance transport parameters from limited observations; it also has the potential to construct local parametric models to benefit the 3D modeling of coastal substance transport. Although the present work takes SSC as an example, it can be extended to any suspended particulate concentration in the water. • A framework is proposed to optimize transport parameters from available observation. • Analytical solution to 1DV concentration equation in unsteady scenario is derived. • Parameters are optimized from best fit of measured and modeled concentration profiles. • The proposed framework is tested with a specially-designed experimental device. • 3 key transport parameters are synchronously optimized with uniqueness and stability. [ABSTRACT FROM AUTHOR]

The sedimentation processes of mud deposits on the continental shelves of the Yellow Sea (YS) are investigated using a combined data analysis and hydrodynamic modeling approach in order to identify the dominant factors that contribute significantly to the formation of these deposits. The data analysis makes extensive use of existing data, especially recently collected deep core data while the hydrodynamic and sediment transport processes are studied using a 3D hydrodynamics model that incorporates the effects of tides, waves and wind. The average deposit rate of the Central Yellow Sea Mud (CS) is estimated to be 3.6 × 10 7 t a − 1 based on high-resolution Chirp sonar profiles combined with core data. Available sedimentological, mineralogical, geochemical and fluid flow data all indicate that the fine sediments discharged from Huanghe River and Changjiang River as well as the resuspended sediments from the Old Huanghe Delta are the main sources for the mud deposits in the Southern Yellow Sea (SYS). This study confirms that tidal current flow is indeed the main agent for transporting the fine sediment to the mud patch in the central SYS but wave effect is also significant as it is responsible for maintaining suspension concentration and causing sediment resuspension. The wave influence is particularly notable around the Old Huanghe Delta in winter storms as during these storm periods current circulation, mainly caused by the Asian Monsoon, can transport a large quantity of fine sediments from the Old Huanghe Delta to the central SYS. Under the present hydrodynamic conditions, the modeling results showed that approximately 16% (1.33 × 10 8 t a − 1 ) of the Huanghe River-derived sediment is transported out of Bohai Strait, of which around 44% (5.72 × 10 7 t a − 1 ) will finally be transported to the South Yellow Sea. The corresponding values without accounting for the wave effects are 9.8% and 2.6%, respectively. It is noted that the deposition rate in the CS mud area over the past 12 kyr is virtually constant despite the significant rise in sea-level and associated changes in the tidal current fields and wave distributions in the Yellow Sea. The reason for this is believed to be that the weaker currents and waves during a lower water period is compensated by the shorter distance the suspended sediments have to travel from the paleo-Huanghe River to the CS mud area, thus maintaining a nearly constant deposition rate in the CS mud area. [ABSTRACT FROM AUTHOR]

The Amazon River has the highest discharge in the world. Nevertheless, there is still a lack of the research on the interaction between river-diluted water and the ocean. This study used the remote sensing data (2008–2017) of the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite, and data of the currents, wind fields, sea surface temperature, and water depth. The river–sea interaction off the Amazon estuary was studied by analyzing the diffusion of river-diluted water and the distribution of surface suspended particulate matter (SPM). The results revealed that the Amazon estuary has a "filter effect," whereby the distribution of the surface SPM exhibited significant spatial characteristics of being high in the nearshore area and low in the offshore area. Most of the SPM accumulated within the estuary in a fan shape, although some was distributed in the shallow water region of the continental shelf along the coasts on both sides of the estuary. The currents were found to limit the diffusion range of SPM. The flow direction and velocity of the North Brazil Current and the North Equatorial Countercurrent, which are largely driven by the magnitude of the trade wind stress, are the main forces controlling the long-distance diffusion of diluted water, thus forming unique river–sea interaction patterns in the Amazon estuary. This research provides a supplement and reference for the study of the diffusion process of SPM and river-diluted water, and on the estuarine river–sea interactions of other large rivers worldwide. [ABSTRACT FROM AUTHOR]

Based on National Oceanic and Atmospheric Administration/Advanced Very High-Resolution Radiometer (NOAA/AVHRR) remote sensing and Cross-Calibrated Multi-Platform (CCMP) wind field data from 2007 to 2019, oceanographic conditions are analysed, respectively, in the Source Area (SA) and Typical Bloom Area (TBA) of Ulva prolifera (U. prolifera) in the west of the Southern Yellow Sea (SYS) using Sea Surface Temperature (SST), Suspended Sediment Concentration (SSC) and Wind Speed over the years. The results indicate that the annual maximum SST Difference (SSTD) between U. prolifera SA and TBA is strongly consistent with the intensity of U. prolifera, and a high SST Warming Rate (WR) from May to July may constrain the U. prolifera blooms. The Taiwan Warm Current (TWC), crossing Yangtze River Estuary northward from March to April, leads to SST increasing in the SA and becomes a key trigger for the growth of U. prolifera in the early period. The amount of U. prolifera may decrease in the early period because of the lower light intensity with high SSC and turbidity in SA. The summer monsoon is one of determinants for the spread of U. prolifera, and the distribution of U. prolifera reaches its highest point with a higher mean wind speed in the TBA. [ABSTRACT FROM AUTHOR]

A tidal shear front (TSF) can be defined as an obvious horizontal gradient of flow velocity formed by opposing tidal currents (reversed TSF) or same-direction tidal currents (homogenous TSF) on both sides of the front with limited impact by river runoff. Observational and modeling studies have been conducted to investigate the impact of a reversed TSF on the transport of freshwater and sediment in the Yellow River Mouth (YRM). The reversed TSF existence period is only about 40% of a tidal cycle (around slack of flood and ebb); however, when this front disappears (around maximum flood and ebb), sediment transport across the frontal zone is still rare. This suggests that the dynamic mechanism of cross-frontal sediment transport in a tidal cycle remains unclear. In this study, synchronous observations of sea current and suspended sediment concentrations along the river mouth profiles at the YRM in 1995, 2003, and 2019 were used to investigate the long-term variation characteristics, mechanisms, and impacts of the TSF on cross-frontal sediment transport. The results indicate that in addition to the reversed TSF, there are also homogenous TSF during flood and ebb tides, with the ebb homogenous TSF being more significant due to tidal asymmetry in the YRM. The ebb homogenous TSF is located between shallow shoals and the slopes of the subaqueous delta front and lasts for about 3 h around the maximum ebb. Its maximum shear strength is similar to that of the reversed TSF, and the formation mechanism is also similar. The presence of the ebb homogenous TSF reduces the efficiency of cross-frontal sediment transport during the ebb. The reversed and homogenous TSFs alternately block sediment moving towards the sea. Thus, terrigenous sediment is difficult to cross the frontal zone to the central Bohai Sea by tidal currents solely. Over the past two decades of low discharge, with the Yellow River implementing artificial water and sediment regulation, the homogenous TSF during the ebb tide has become more and more important and cannot be neglected for cross-frontal sediment transport under normal conditions. Furthermore, from a long-term perspective, the shear strength of the TSF is positively correlated with the distance of river mouth siltation into the sea. Additionally, salinity and turbidity gradients are also positively correlated with the shear strength in the estuary. This indicates that the blocking of cross-frontal sediment transport by the TSF is a key process in river-sea interaction in the YRM. • The tidal shear fronts (TSFs) evolution and their impact on cross-frontal sediment transport are revisited. • The homogenous TSFs are found as one of the key sedimentary dynamic factors too. • Fluvial sediment seaward transport is hindered not only by reverse TSFs, but also ebb homogeneous TSFs. • Interaction between topography, TSFs, and sediment transport is a key process in long-term river-estuary-sea interaction. [ABSTRACT FROM AUTHOR]

The hazardous exposure and self-burial of a submarine pipeline were studied based on the investigation of a submarine pipeline in the sand wave area in the South China Sea, as well as on statistical data and mathematical calculations. The results indicate that the pipeline free span in the area was mainly induced by seabed erosion, sand wave movement, and human disturbance. Extreme weather events cause severe impacts on seabed topography and the pipeline condition. The burial status of the pipe is mainly controlled by the evolution of local seabed topographical conditions, i.e., the amount of sediment load and the movement of seabed sand waves. The migration of the continuous small-scale sand waves facilitates the self-burial of pipes, while the migration of isolated large-scale sand waves creates potential hazards for pipelines because of the existing free span continues to grow on both sides of the sand wave. [ABSTRACT FROM AUTHOR]

Abstract: Mud deposits are widespread in estuaries and on continental shelves, and contain important information regarding interactions between terrestrial and coastal processes. Magnetic properties of muddy sediments from the northeastern continental shelves of China, including shelves close to Korean coasts, were analyzed using bulk and size-fractionated samples to elucidate muddy sediment sources and transport. Types, concentration, and granulometry of magnetic minerals were determined and all samples were found to be dominated by magnetite. Muddy sediments from the Zhemin coast (off the Zhejiang and Fujian coasts) have the highest magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) values, while those from the central and southeastern South Yellow Sea and the western Korea Strait have lower values reflecting lower magnetic mineral concentrations. Single domain ferrimagnetic grains dominate the magnetic particles in the central South Yellow Sea, while superparamagnetic (SP) grains contribute significantly to the magnetic grains in the Bohai Sea. SP and coarse multi-domain (MD) grains dominate magnetic grain assemblages in the North Yellow Sea and along the Zhemin Coast. Rock sediment particle size is not a major factor affecting the magnetic properties of the mud deposits in the study area. Rather, terrigenous inputs and hydrodynamic transport processes primarily control the magnetic properties, and sediments from the Changjiang and Huanghe rivers make the most significant contribution. This observation applies to the whole study area, although terrigeneous magnetic mineral concentrations decrease with increasing distance from the river mouths due to both sorting and mixing with other sediments with weak magnetic signatures. Bacterial magnetosomes also play a role in the central South Yellow Sea. [Copyright &y& Elsevier]

Abstract: Provenance discrimination of marine sediments is an important topic in marine geology. Although the catchments of the Changjiang and Huanghe Rivers are regarded as the main sources of sediments on the shelves of the China Sea, identification of detailed sediment provenance is necessary for understanding sediment transport patterns and the paleoenvironment. Magnetic properties of both bulk sediment samples and different-sized particles from the Changjiang and Huanghe Estuaries are studied to discuss the origin of the sediments. The results show that the sediments are dominated by ferrimagnetic magnetite with a minor content of anti-ferromagnetic minerals such as hematite, and a higher concentration of ferrimagnetic minerals is observed for the Changjiang Estuary sediments. The crystal grains of ferrimagnetic minerals in the Changjiang Estuary are coarser than those in the Huanghe Estuary, whereas superparamagnetic grains significantly contribute to the Huanghe sediments. Magnetic parameters of χ SIRM, SOFT and χ ARM from different-sized particles present more obvious differences than these parameters from bulk particles, and S−100 and S−300 for both bulk samples and different-sized particles show distinct differences between the sediments from the two estuaries. Therefore the latter parameters are more useful to distinguish sediment origins. A comparison of the magnetic properties of sediments in these two estuaries with those on the shelves of the adjacent China Sea also suggests that the analysis of sediment magnetic properties is effective to identify sediment provenances. [Copyright &y& Elsevier]

The rock magnetic properties of surface sediments from the fine-grained depositional area on the outer shelf of the East China Sea, an area surrounded by sands, were investigated with a view to providing information on the sediment provenance. Multiple magnetic parameters such as magnetic susceptibility, anhysteretic remanent magnetization, saturation remanent magnetization (SIRM), coercivities of SIRM, and S ratios (relative abundance of low-coercivity magnetic minerals) were measured for all 179 surface samples, and partial representative samples were examined for their magnetic hysteresis parameters, temperature dependence of magnetic susceptibility and X-ray diffraction spectra. Our research indicates that the magnetic mineralogy is dominated by magnetite with a small amount of hematite and is primarily of a pseudo-single-domain to multidomain nature with a detrital origin. The magnetic concentration in the study area generally decreases to the east or southeast accompanied by magnetic particle fining to the east or northeast. The geographic pattern of magnetic properties is most reasonably explained by a major source of sediment jointly from the erosion of the old Huanghe River deposit and the discharge of the Changjiang River. The rock magnetic data facilitate understanding of the transport mechanism of fine-grained sediments in the outer shelf of the East China Sea. [Copyright &y& Elsevier]

Bedforms like ripples are widely distributed in the coastal zone. They influence the bed roughness thus the estimation of bed shear stress and associated sediment transport. An echo sounder was mounted on a bottom-supported tripod intended to measure the erosion and deposition of seabed in the subaqueous Yellow River Delta, China. However, variations in bed elevation are found to be not the net erosion or deposition at the observation site, but the migration of silt ripples which were generated by waves and pushed back and forth or flattened off by the tidal currents. Ripple heights were observed to be within 0.1–0.7 cm and were used for testing the model of Nielsen (1981). The model overestimated the height of silt ripples as it was developed for sands, but the deviation can be well addressed by incorporating a linear modification (R 2 = 0.79). Alternatively, a new model specifically for silt ripple height was regressed from the field data with R 2 up to 0.78. The existence of silt ripples increases the bed shear stress by 4 times due to the additional bed roughness. A "fluffy layer" overlies the consolidated seabed, therefore, net seabed erosion occurs after the "fluffy layer" is resuspended. A representative critical bed shear stress for net seabed erosion in the study area was found to be 0.8 Pa. The echo sounder can be an alternative tool for observing silt ripples in coastal regions like the Yellow River Delta where the water is too turbid for underwater videos. The proposed model infers silt-ripple features from bed grain size and flow condition and provides a quick estimate for bed roughness improving the understanding on sediment transport. • A new model for silt ripple height is proposed based on field observation. • Bed shear stress is better estimated by incorporating bed roughness due to silt ripple. • Critical shear stress for erosion is inferred from field observations. • Echo sounder is used for observing silt ripples in turbid waters. • Ripple height is inferred from field-measured bed elevations. [ABSTRACT FROM AUTHOR]

Uncovering the spatial distribution of deep-sea sediment lithologies is crucial for the research on earth system science and the exploration of critical mineral resources. The conventional global deep-sea sediment lithology distribution maps showed that the lithologies were relatively uniform in the global major ocean basins. Furthermore, it was deemed that the deep-sea sediment lithologies were related to the productivity of surface seawater. However, later studies have illustrated that the distribution of deep-sea sediment lithologies exhibited greater variability and heterogeneity than conventional maps and that water depth played a more important role in controlling deep-sea sediment lithologies than productivity. In addition, few studies have focused on the relationship between the heterogeneous deep-sea sediment lithologies and the diverse seafloor topography in the West Pacific. In this study, we provide a high-resolution spatial distribution map of deep-sea sediment lithologies by systematic descriptions of 112 surface samples in the northern West Caroline Basin, tropical West Pacific, with a large range of water depth and a diverse seafloor topography to verify the previous prediction of sediment lithology distribution. Subsequently, based on the results of the determinations of carbonate and biogenic silica contents, the sediment redox-potential tests, and the calculations of multiple variables, we carried out quantitative studies and correlation analyses for these variables to reveal the relative contribution of different factors to the lithological heterogeneity in the northern West Caroline Basin. Our results show that the actual deep-sea sediments have greater heterogeneity in terms of lithological classes and distribution patterns than the earlier predicted lithology maps. Furthermore, our analyses reveal that water depth and seafloor topography are the more important controlling factors on the deep-sea sediment lithology to some extent than productivity and that water depth and topography may exert different effects on the different sediment components. For the calcareous component, water depth is the main controlling factor due to the increased solubility of carbonate with water depth. Carbonate materials can dilute other components in the waters above the carbonate compensation depth, which is around 4500 m below the sea surface in the study area. Meanwhile, the siliceous component may be enriched in the unique negative seafloor topography of the trench and trough with the specific lateral transport mechanism and the redox environment. These findings imply a more complicated actual deep-sea sediment lithology distribution than previously thought given that various water depths and diverse topography in the global oceans, which are significant for understanding deep-sea sedimentary processes and improving the models for predicting global sediment lithology in the deep sea. • Deep-sea sediments in the northern West Caroline Basin are characterized. • The measured sediment lithologies show greater heterogeneity than predicted. • Sediment lithologies are mainly determined by water depth and seafloor topography. • A model of causing the lithological heterogeneity in the study area is established. [ABSTRACT FROM AUTHOR]

Waves are fundamentally important for sediment re-suspension in estuary and coastal areas, especially for silty sediments, which can be easily suspended by waves, but the differential effects of swell and wind waves are still unclear. Integrated field observations were made from November 2012 to March 2013 including waves, currents, and suspending sediments on the offshore seabed of the Huanghe Delta to explore the mechanism of sediment re-suspension in silty coastal zones. During the five months of observation, there were more than 30 winter wind events that affected the study area and induced sediment re-suspension with varying suspended sediment concentration. The observed wave composition was separated into swell and wind waves using a bandpass filter. Results show that large swell (with significant height > 1.0 m) coming from the offshore direction (NE in our study area) dominated sediment resuspension in the coastal seabed due to the fact that this wind direction had the longest average fetch. Winds from the onshore direction usually had smaller swell due to their short fetches and caused limited sediment re-suspension. The residual currents caused by NE winds also transport larger sediment. An individual NE wind event could transport sediment 8–13.6 t/m2 and 5.1–8.2 t/m2 in directions parallel and perpendicular, respectively, to the isobaths, which is much higher than the sediment transportation during an individual NW wind event, which could transport 1.5–4 t/m2 and 0.6–5 t/m2 parallel and perpendicular, respectively, to the isobaths. Our research shows that large swell and the accompanying residual currents caused by NE winds (from offshore direction) are a vital driving force for sediment resuspension and transportation in the offshore zone. • The height of swell strongly affected sediment resuspension in coastal seabed. • Large swell coming from offshore (NE in our study area) dominated sediment resuspension events in offshore zone (water depth >10 m). • During and after swell, residual currents are the major dynamics that transport sediment from coastal areas. • Abstract. [ABSTRACT FROM AUTHOR]