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This paper presents the first results of the quantitative reconstruction of ice conditions in the Arctic based on a comparison of the data for periods of meteorological observations with variations in the chemical compositions of the sediments accumulated during the same times. The biogenic elements (Br, Ca, and Sr) and some redox-sensitive (As and Fe) elements are the most informative for the reconstruction of changes in ice conditions with positive correlations, and the lithogenic elements (K and Ti) are predominantly negatively correlated. The reconstruction results for the last 300–400 years of average annual air temperature anomalies for all cores in general terms coincide with the reconstruction for the Northern Hemisphere. The common features of all reconstructions are low temperatures during the Little Ice Age (LIA) and a rapid warming in the middle of the 19th century and in the last decades of the 20th and first decades of the 21st centuries. The results of the reconstruction of the duration of the ice-free period generally coincide with the temperature changes for the last two centuries, although for LIA there is an inverse correlation between the variations in temperature and the duration of the ice-free period. A possible reason for this may be changes in the structure of the surface currents in the Chukchi Sea and the northern part of the Bering Sea, because of which the inflow of warm and freshened waters through the Bering Strait to the Arctic increased occasionally. [ABSTRACT FROM AUTHOR]

Compared with other newly developed urban areas, urban villages in China are in greater need for redevelopment. Governed by institutions inherited from the local-state-dominated dual land ownership system, the redevelopment of these villages follows a state-led land requisition system, which confers development rights to local governments while limiting the rights of village collectives. Two other complementary arrangements include the top-down land use planning system and the state-monopolized land transfer system. Although these institutional arrangements favor land conversion in greenfield development, they cannot be easily implemented in the village redevelopment process. By reviewing the redevelopment policies and practices, this study empirically examines the redevelopment of urban villages in Shenzhen during the policy period from 2004 to 2009 and adopts the transaction cost perspective in analyzing how state-led institutional arrangements have resulted in many time-consuming transactions and hindered the redevelopment of urban villages. [ABSTRACT FROM AUTHOR]

In order to reconstruct the history of primary paleoproductivity changes during the last 160 kyr in the Okhotsk Sea (OS), the high-resolution down-core analyses of chlorin content were performed on 11 sediment cores obtained from various part of the studied area with wide ranged depths. Spatial and temporal distributions of the marine phytoplankton paleoproductivity depend on sea ice condition and nutrient supply. The observed discrepancies among the reconstructed records allow us to separate out three main regions with specific environmental conditions. During glacial stages the paleoproductivity was depressed and vice versa. Productivity in the central region is low comparing to other regions due to nutrient limitation. Increased paleoproductivity in the southeastern area was affected by influence of nutrient-rich Pacific waters. [ABSTRACT FROM AUTHOR]

Urban renewal has become an essential part of the ongoing urban development in China. This study provides a citywide analysis on the spatial determinants of land redevelopment activities in the urban renewal processes in Shenzhen, China. Based on the concept of rent gap and a perspective of transaction costs, a conceptual framework is developed to understand land redevelopment behaviors and analyze how location factors, land property rights, land use status and urban planning collectively affect land redevelopment outcomes. Empirical analysis is conducted based on logistic regression models with unique parcel-level data of all urban renewal projects in the entire city of Shenzhen and in special economic zone (SEZ) and non-SEZ areas. This study shows that urban sites with high land rent gap levels and low transaction costs are more likely to be redeveloped earlier. Aside from location factors, land property rights, land use status and urban planning all have a significant influence on the spatial variation of land redevelopment activities. These factors have varied effects on land redevelopment in the SEZ and non-SEZ areas due to the institutional differences and development conditions in these two areas. The research findings suggest the need for further policy considerations to better guide land redevelopment toward sustainable development. Redevelopment policies and regulations should also consider the dissimilar redevelopment conditions of different regions. • A citywide analysis on spatial determinants of land redevelopment is conducted based on parcel-level data. • Urban sites with a higher level of land rent gap and a lower level of transaction costs are more likely to be redeveloped. • Location factors, land property rights, land use status and urban planning collectively affect redevelopment outcomes. • The effects are different in SEZ and non-SEZ areas due to the institutional differences and development conditions. [ABSTRACT FROM AUTHOR]

The nanoscale morphology of solution processed bulk heterojunctions is governed by miscibility of donor and acceptor in the selected solvent and drying of the layer during processing. Ternary blends are of great interest for high efficiency polymer solar cells, but prediction of their morphology is highly complex. Here we perform atomistic simulations to study the miscibility of three different polymers of interest for ternary organic photovoltaics (the small band gap polymers PTB7 and PTB7-th, and the sensitizer Si-PCPDTBT) with the fullerene acceptor PC 71 BM. The free energy of mixing of fullerenes with polymers is calculated as a function of the relative concentration. The blend density is also varied to simulate out-of-equilibrium conditions occurring during layer processing. By analyzing the results within the Flory–Huggins theory we find that, for a specific range of fullerene weight ratios and densely packed blends the sensitizer is most likely located in the host polymer phase due to its low miscibility with the fullerene. This configuration is the preferred one for the solar cell in order to deactivate hole traps typically formed in the binary blends and reduce recombination. Notably, we find that these results can be different qualitatively at lower density and in out-of-equilibrium blends. This work shows that weight ratios and density can be in principle chosen to select specific morphologies in ternary organic blends. [Display omitted] • The mixing free energy F governs the nanoscale morphology of bulk heterojunctions. • Out-of-equilibrium conditions can alter qualitatively the morphology of the blends. • We calculate F for a variety of weight ratios also in out-of-equilibrium conditions. • Weight ratios and density can be chosen to select specific morphologies in blends. [ABSTRACT FROM AUTHOR]

The Western Subarctic Gyre (WSG) in the North Pacific represents the termination of the Atlantic Meridional Overturning Circulation (AMOC). It has been strongly influenced by periodic glaciations of adjacent landmasses, orbital- and millennial-scale variability of its environment, and ventilation, which, to date, have been poorly studied. In this study, we investigated sediment core LV76-21 recovered from the Detroit Seamount using several productivity and lithological proxies, δ18O records of planktic and benthic foraminifera (δ18Opf and δ18Obf), AMS 14C data. We also used the published results from three well-dated cores from the Detroit and Tenji Seamounts. Comparison of the δ18Opf and δ18Obf records allowed us to establish iceberg discharge events 1 and 1' at 39–36.8 and 42–40 ka, respectively, in the WSG over the last 43 kyr. This was accompanied by considerable lightning of δ18Opf relative to the coeval δ18Obf values. The lithological results have also shown variable sea-ice influence on the regional environment during Marine Isotope Stage 3 and particularly 2, with sea ice extensions at 28.5–25.5 ka and 17.6–16.6 ka, and its significant loss since the Bølling–Allerød warming. We used high resolution δ18Obf records from studied cores as a subtle proxy of contribution of North Atlantic Deep Water (NADW) to Lower Circumpolar Deep Water (LCDW), which originating from around Antarctica and have slightly different δ18Obf values, in order to reconstruction of its spatial variability in the context of regional deep-water ventilation. The contribution of NADW to LCDW in the ventilation of the western flank of Detroit Seamount significantly increased during the interglacial and long-lasting Dansgaard–Oeschger interstadials, which was synchronous with the AMOC intensification. Over the last 43 kyr, the deep water of its eastern flank has been constantly ventilated by the LCDW with low contribution of NADW. • ●Sediment core LV76-21 recovered from the Detroit Seamount is analyzed. • ●Productivity and lithological proxies, δ18O records, and 14C data are derived. • ●Iceberg discharge and sea-ice influences are identified over the last 43 kya. • ●NADW inputs into deep-water ventilation are synchronous with AMOC intensification. • ●The eastern flank of the Detroit Seamount has been constantly ventilated by ABW. [ABSTRACT FROM AUTHOR]

Coarse fraction (CF) content, grain-size distribution, roundness of CF, gravels and pebbles, and examination of surface of pebbles were studied in core LV28-44-4, recovered from the eastern Okhotsk Sea (OS). The age model of the studied core was based on the AMS 14 C data, tephrochronology, δ 18 O benthic foraminifera record, and correlation of peaks of productivity proxies with long-lasted Dansgaard-Oeschger (DO) interstadials. The results show that sea ice was the main transport agent for CF (ice-rafted debris, IRD) in the eastern OS. Published mineralogical studies of clastic material of the OS indicated that the coast of western Kamchatka was the main source of IRD in the eastern OS. We found 19 peaks of IRD, which mostly coincided with DO stadials. The distribution of CF indicates a different pattern of IRD supply during MIS 4, 3, and 2. Comparison of IRD records in the eastern and central parts of the OS allow us to reconstruct millennial changes in ice and wind modes for MIS 4–MIS 2. Significant strengthening of northeastern and eastern winds during DOSs of MIS 3 and of northern and north-western winds during MIS 2 were observed. [ABSTRACT FROM AUTHOR]

As the main heat and water mass sources, the warm and saline Pacific waters have significant influence on sea ice and intermediate water circulation in the Sea of Okhotsk (SO). However, the long-term history of Pacific warm water intrusion into the SO remains unknown, impeding accurate predictions of its future changes. In this study, provenance proxies (clay mineral assemblages and trace element ratios (<2 μm)) from surface sediments and Site LV87-55-1 were used to investigate the history of Pacific water intrusion into the SO over the past 20 kyr. Provenance analysis indicates that sediments in the central SO primarily originated from the Amur River before 11.7 ka, with a significant rise in sediment input from the Kamchatka Peninsula since that time. By integrating published data on sediment grain size, sea surface temperature (SST), and sea-ice diatoms, we observed that the enhanced inflow of Pacific warm water into the SO led to intensified counterclockwise surface currents and the retreat of sea ice since the early Holocene, which subsequently resulted in a noticeable shift in sediment sources in the central SO. Furthermore, based on modern observation and TraCE-21 model simulations, we deduce that the intensified Aleutian Low (AL) since the early Holocene stimulated the East Kamchatka Current (EKC) through increased Sverdrup transport caused by cyclonic wind patterns. This, in turn, facilitated greater intrusion of Pacific warm water into the SO. Overall, our findings suggest an increase in Pacific warm water intrusion into the SO under future global warming scenarios, potentially posing a significant threat to the marine environment of both the SO and the subarctic Pacific. • Provenance records indicate enhanced intrusion of Pacific water into the SO since 11.7 ka. • Increased warm water intrusion results from enhanced Aleutian Low since 11.7 ka. • Future warming climate would stimulate more Pacific water intrusion into the SO. [ABSTRACT FROM AUTHOR]

The Sea of Japan, located in the humid zone, was subjected to significant freshening of surface waters and a decrease in ventilation of deep waters during the glacial eustatic drop in relative sea level (RSL) and a decrease in water exchange with Pacific due to the shallowness of its straits. As a result, the δ18O values of planktic foraminifera (δ18O pf) decreased by several ppm, in contrast to the increase of ones in the Red Sea, depending on the degree of RSL drop. The good preservation of planktic foraminifera in the sediments of the Sea of Japan during the Last Glacial Maximum (LGM) and deglaciation allows us to significantly refine and supplement the available evidences of the global sea level changes over the 33–15 ka. Based on the obtained and published records of δ18O pf of five cores from different parts of the sea and the general chronology of the accumulation of dark layers in the sediments of the Sea of Japan, we calculated the δ18O pf stacks with high and low resolution (0.13 kyr for two cores and 0.5 kyr for other three cores) for the time 33–15 ka. Both stacks showed significant RSL falls at the onset of LGM (32–29 ka), during 21.8–20.3 ka, and an abrupt rise at 17 ka consistently with previously published data. The higher resolution stack additionally showed two phases of RSL falls at the onset of the LGM followed by a slow decrease until 22 ka, with a short and abrupt descent at around 25 ka. According to both stacks the lowest sea level around 18.5–17.5 ka was preceded by a short rise just before 19 ka. A significant RSL rise at 17 ka was followed by an abrupt and short fall at nearly 16.5 ka and then prolonged rise since around 16.2 ka. • Two stacks of planktic foraminifera δ18O records were calculated over the 33-15 ka with a higher and lower resolution. • Chronology was based on synchronicity of dark layers formation ruled by surface water salinity and ventilation changes. • Both stacks showed significant relative sea level (RSL) falls at 32–29 ka, during 21.8-20.3 ka, and abrupt rise at 17 ka. • A higher resolution stack additionally showed millennial-centennial RSL changes over Last Glacial Maximum and since 17 ka. [ABSTRACT FROM AUTHOR]

The age model of the western Bering Sea core 85 KL was modified through correlation of new and earlier-measured productivity proxies with the Chinese interstadials described by δ18O records of Hulu and Sanbao caves and the relative paleointensity events in the studied core with those in the dated records. Resulted sequence of millennial scale Bering Sea Interstadials recorded by abrupt productivity risings was established during the penultimate glacial consistently with the Chinese interstadials and Antarctica isotope maxima. The pattern of the frequency and amplitude of the millennial productivity/climate variability in the Bering Sea during the penultimate glacial resembles that initially depicted in the δ18O of Chinese cave stalagmites and is quite similar to one of the Dansgaard–Oeschger cycles during last glacial, except for their terminations. Contrary to well-pronounced interstadial A.1 during termination TI, an interstadial B.1 over the TII has lower duration and therefore is weakly observed in Antarctic temperature changes. Our results provide robust evidence that the bipolar seesaw mechanisms of millennial climate changes in the Northern and Southern Hemispheres were similar during the last and penultimate glacials. [ABSTRACT FROM AUTHOR]

The UV excited emission properties of mesoporous silica in the blue and UV range are modified by the adsorption and desorption of oxygen molecules at the two defect sites. To interpret the experimental purging cycles we model the oxygen-silica interaction at thermodynamic level, succeeding in explaining the interaction mechanism and the trend of UV centre to undergo photo-bleaching when excited under vacuum conditions. The analysis called for the presence of two different set of defects for both the centres, pinpointed as defects liable to interact with O 2 and non-interacting isolated defects. To support the thermodynamic analysis, we simulated the O 2 adsorption and desorption processes within the first principles DFT cluster framework. The calculated atomic configurations and the potential energy curves along selected probable reaction paths allow suggesting the kinetics of molecular oxygen interaction on examined surface silica defects and pointing at an oxygen vacancy E’-like defect as the possible result of the UV centre photo-bleaching. [ABSTRACT FROM AUTHOR]

High resolution of the color lightness, productivity proxies (TOC, chlorin, CaCO 3 , Ba-bio, Mo and U), and lithological description defined alternation of dark layers (DLs) and light layers in sediment core LV53-23 recovered from the central Japan Sea (west Yamato Rise) over the last 75 ka. Age model was constructed by AMS 14C data, tephrochronology, δ 18 O of planktonic foraminifera record, and the correlation of DLs with lightness of Japan Sea core MD01-2407 and with millennial interstadials recorded in the Greenland ice cores and East Asia stalagmites. Regional interstadials were also independently established and dated by vegetation amelioration of the surrounded land, inferred from the pollen results. Correlation of the DLs with millennial scale climate and sea level changes indicate that both interstadial warming and sea level fluctuations influence on its formation providing their individual features. During MIS 3, with sea level above −90 m, DL was formed mostly consistent with the Tada et al. (1999)’s hypotheses. During MIS 2 and 4, when sea level was nearly and below −90 m, sea level descending led to water column stratification, oxygen depletion in bottom water and facilitates the DLs formation. High-resolution lightness and productivity proxies defined the subtle structure of pronounced interstadials 14 and 12. [ABSTRACT FROM AUTHOR]

Abstract: We measured productivity proxies (chlorin, carbonate and organic carbon, opal, and biogenic Ba content) and lithophysical proxies (magnetic susceptibility, water content, density, and coarse sediment fraction) in sediment of central Okhotsk Sea core PC-7R. The age model covering the last 350kyr of this core was constructed by correlating the dated series of relative paleointensity lows recognized in geomagnetic intensity records, marine isotope stage (MIS) boundaries determined in broad variations of the lithophysical and productivity proxies, and tephrochronology. The orbital changes of the lithophysical and productivity proxy stacks lag behind Northern Hemisphere summer radiation by approximately 6.3 and 5.9kyr, respectively. This lag is consistent with a Milankovich model of climate control by solar radiation through the northern ice sheet volume and sea surface and surrounding land responses, which are fast compared with sedimentological evidence. Productivity proxies of the Okhotsk Sea also demonstrate 52 abrupt, pronounced productivity minima associated with regional climate coolings during the last 350kyr, which present useful indicators of millennial-scale climate changes in this marginal sea. Based on the postulated synchronicity of Dansgaard–Oeschger cycles in the Northern Hemisphere and the established simultaneity of 11 Okhotsk Sea coolings in the last 77kyr with abrupt severe cold events in the Greenland ice core and North Atlantic Heinrich events, all of these may be regarded as Heinrich-equivalent event anomalies. The Okhotsk Sea events have their counterparts in the records of North Atlantic sediments, the Greenland ice sheet, East Asia summer monsoon, and the Antarctic ice sheet. Probably the Arctic Oscillation was the main factor determining orbital and millennial climate oscillations in the high-latitude Northern Hemisphere, including the Okhotsk Sea region. [Copyright &y& Elsevier]

Evidence of meltwater and ice rafted debris from the Tenji and Detroit seamounts in the northwestern corner of the North Pacific are key to understanding ice sheet dynamics across the Kamchatka Region. Marine isotopic stages 6.5–1 were established in this study for the Tenji Seamount sediment core based on accelerator mass spectrometry (AMS) 14C data, benthic foraminifera δ18O stratigraphy, and relative paleointensity excursions. Records of planktic foraminifera δ18O and ice rafted debris (IRD) in sediment cores pertaining to the last 190 kyr were used to outline several periods of surface water freshening and increased accumulation of coarse terrigenous grains induced by iceberg supply and melting in the northwest Pacific. Iceberg discharge events (IDEs) were reconstructed over the last and penultimate glacial periods in the central and eastern parts of the Okhotsk Sea and southwestern part of the Bering Sea using relevant published proxies. Similar reconstructions of IDEs were also performed for two published sediment cores from the Detroit Seamount. Synthesis of planktic foraminifera δ18O and IRD records along with other related proxies from the studied areas concordantly revealed five IDEs in the northwest Pacific and its marginal seas during the last 190 kyr: IDE 1 (42–29 ka), IDE 2 (76–57 ka), IDE 3 (118–110 ka), IDE 4 (152–141 ka), and IDE 5 (179–160 ka). Data showed that IDEs 4–1 occurred at low values of Earth obliquity and under a weak Aleutian Low, facilitating snowfall precipitation and enhancing glacier formation at Kamchatka, which is a priority area for capturing atmospheric moisture transferred into northeast Asia. Compared with the other IDEs, IDEs 2 and 5 were more pronounced and prolonged events over the last 190 kyr. In addition, IDE 2 was also characterised by a catastrophic and short IRD peak that was probably forced by the influx of lake water from the Central Kamchatka Depression. It is likely that IDEs 2 and 1 occurred during phases I (more extensive) and II (less extensive) of the published Kamchatka glaciations during the Late Pleistocene. • Planktic δ18O and ice rafted debris as tools for iceberg discharge in the NW Pacific. • Dated records of iceberg evidences in sediments of NW Pacific and marginal Seas. • Five dated iceberg discharge events (IDE) in NW Pacific inferred by data synthesis. • Five periods of Kamchatka glaciations related with NW Pacific IDEs over last 190 ka. [ABSTRACT FROM AUTHOR]

The response of benthic foraminifera (BF) and radiolarian production in the central Okhotsk Sea (OS) to orbital and millennial changes of climate and environment over the last 136 kyr have been studied on the basis of the sediment core PC-7R, with available productivity, geochemical and lithological records and a modified age model. We used the calculated accumulation rate of microfossils (AR, fluxes) of the main ecological groups and species indicative of radiolarians and of BF as quantity responses in their production, which is related to environmental and hydrological changes of the water column and surface sediment in the central OS and to global and regional climate changes. The responses of the opportunistic BF Alabaminella weddellensis and the suboxic group during the last 136 kyr were mostly related to changes in organic fluxes from the surface, sea ice cover and surface sediment oxygenation at both orbital and millennial time scales. The AR of radiolarians from the surface, dichothermal and mesopelagic groups significantly differed from the AR of BF. The AR has a maximum during the middle and late Marine Isotope Stage 5e and lower values during the earlier Holocene, while the minimum happened during cold Marine Isotope Stages 6, 4 and 2 with maximal ventilation of OS intermediate water. Production of the mesopelagic radiolarian Cycladophora davisiana in the OS was mostly related to the lateral delivery of terrigenous material and OM into the water column from the northwestern shelf and/or from the western subarctic Pacific. Due to the sensitivity of marine organisms to environmental conditions, the production of radiolarians and BF sharply changed with the extinction of Amphimelissa setosa, since Heinrich Stadial 8 is related to the termination of global environment cooling and the hydrology changes of the early last glacial. • Benthic foraminifera and radiolarian responses in Okhotsk Sea to orbital and millennial climate changes over last 136 kyr. • Production of benthic foraminifera mainly changes in response to autochthonous organic fluxes to floor and sea ice cover. • Production of surface, dichothermal radiolarian and Amphimelissa setosa varied broadly synchronously with productivity. • Production of C. davisiana was responded to organic transport from subarctic western Pacific and northwestern Okhotsk Sea. • HS 8 in the Okhotsk Sea denotes the termination of the Northern Hemisphere climate cooling with extinction of A. setosa. [ABSTRACT FROM AUTHOR]

• The diatom content of a sediment core from the Sea of Okhotsk was studied. • Diatoms were used to reconstruct the environmental changes over the last 94 kyr. • Local warming and cooling events and fluctuations in the sea level were documented. • First report of a shift from interglacial to severe glacial conditions in the area. This paper presents the results of a study on a sediment core obtained from the southwestern part of the Sea of Okhotsk. By analyzing the diatoms in the sediment, along with the productivity proxy and ice-rafted debris data, we reconstructed the regional environmental and climatic changes occurring over last 94 kyr (sea-ice expansion, periods of active ice melting, and variations in marine plankton productivity). Local warming and cooling events occurring in the Late Pleistocene and Holocene periods, as well as transgressive-regressive fluctuations in the sea level, were documented. The shift in the relatively warm interglacial conditions to severe glaciation over 34 kyr ago that occurred in the studied area of the Sea of Okhotsk was reported for the first time. The time at which the La Pérouse Strait opened, the Soya Current input began, and the establishment of modern hydrological conditions was approximately 5.6 kyr. [ABSTRACT FROM AUTHOR]