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• We theoretically and experimentally presented an investigation on the difference of TMI effect based on a series of gain-filtering Yb-doped fibers with different doping ratios, which is of interest to the community of high-power fiber lasers. • Four gain-dopant diameter ratio fibers, entailing 100% doping, ∼73% doping, Gaussian doping, and ∼57% doping, were fabricated by MCVD combined with solution doping technique. The TMI thresholds of four fibers were measured to be ∼1753 W, ∼3089 W, ∼3048 W, and over 3301 W, respectively, of which below the TMI threshold, the beam quality M2 factors were tested to be ∼1.52, ∼1.40, ∼1.45, and ∼1.32, respectively. • It meant that the TMI thresholds of ∼73%-doped, Gaussian-doped, and ∼57%-doped fibers were 1.76 times, 1.74 times, and over 1.88 times as much as that of 100%-doped fiber, respectively. Meanwhile, the simulated results also agreed well with the experimental results. The experimental and simulated results indicated that as the gain-dopant doping diameter reducing, the better gain-filtering effects of higher TMI threshold and more superior beam quality was manifested. We presented an investigation on gain-filtering Yb-doped fiber for the mitigation of transverse mode instability (TMI). The gain-filtering Yb-doped fibers were fabricated by modified chemical vapor deposition (MCVD) combined with solution doping technique. Four gain-dopant diameter ratio fibers, entailing 100% doping, ∼73% doping, Gaussian doping, and ∼57% doping, presented similar parameters with the core/inner cladding diameter of ∼30/400 μm and core numerical aperture (NA) of ∼0.061. The laser performances of four fibers were demonstrated by a bidirectional pumping all-fiber amplifier. The TMI thresholds of 100%-doped, ∼73%-doped, Gaussian-doped, and ∼57%-doped fibers, were measured to be ∼1753 W, ∼3089 W, ∼3048 W, and over 3301 W, corresponding to the M2 factors of ∼1.52, ∼1.40, ∼1.45, and ∼1.32, respectively. The experimental results indicated that by reasonably tailoring the gain-dopant doping diameter, better gain-filtering effect was manifested, exactly as higher TMI threshold and more superior beam quality. This contribution could provide an effective approach for obtaining high-brightness Yb-doped fiber amplifiers based on gain-filtering effect. [ABSTRACT FROM AUTHOR]

Temporal and spatial variation of sea ice type in the Arctic is an indicator of regional and global change. Arctic sea ice can be classified into two major categories: multiyear ice (MYI) and first-year ice. In this paper, classification method based on machine learning is established and applied to produce daily sea ice classification data set during the winter (November–April) from 2002 to 2017 using active microwave data from QuikSCAT and Advanced Scatterometer as well as passive microwave data from Advanced Microwave Scanning Radiometer for EOS, Special Sensor Microwave Imager/Sounder, and Advanced Microwave Scanning Radiometer 2 radiometer. First, the open water area is flagged out using brightness temperature (Tb) from the passive microwave sensor. Then, K-means algorithm is applied to identify the clusters of the two ice types in the Tb/backscatter parameter space and finally assign pixels to each class. Two optimization methods based on the movement of MYI and marginal ice zone are used to correct the misclassification of MYI. The results have shown a decrease of MYI in winter from 2002 to 2017, especially in 2008 and 2013 with a remarkable recovery in 2014. The classifications are consistent with results by visual interpretation from synthetic aperture radar images in the Canadian Arctic Archipelago with overall classification accuracy over 93%. Comparison with classifications from previous studies and products shows that our method could reflect more differences in MYI declining trend interannually and less anomalous fluctuations in certain years. [ABSTRACT FROM AUTHOR]

The mandarin fish, Siniperca chuatsi , is an economically fish with delicious flesh and rich nutrients. Artificially induced polyploid is an effective methods of breeding superior species of fish. The increasing frequency of mosaicism in the research of fish polyploidy has attracted the attention of many scholars. In this study, hydrostatic pressure shock caused an abnormal cleavage of fertilized, larvae treated with pressure shock displayed reduced fertilization, hatch and survival rates. Mosaics that both have diploid and tetraploid cells were induced in mandarin fish. The effective condition was applying 500 kg/cm2 pressure at 45 min after fertilization for 2 min at 25 °C, the occurrence of 44.5% diploid/tetraploid mosaic fish was confirmed by flow cytometry determination of DNA content. Mosaic mandarin fish has the ability to incubate and grow, and the body weight and body length analysis showed no significant difference between mosaic and diploid individuals. However, after the hydrostatic pressure shock, delayed embryonic development and body deformities were observed, and the body spot and stripe have largely changed in experimental mandarin fish. • Survivable mandarin fish Siniperca chuatsi diploid/tetraploid mosaics obtained by hydrostatic pressure shock induction. • Hydrostatic pressure shocked at 500 kg/cm2 for 2 min was optimal for mandarin fish Siniperca chuatsi mosaic induction. • Changes in body spots and stripes appeared in mandarin fish after hydrostatic pressure shock. [ABSTRACT FROM AUTHOR]

• Design and fabricate an Yb-doped cladding uniform core tapered fiber (CUCTF). • The CUCTFs with two different structures are compared in experiment and theory. • The CUCTF with the wide to narrow structure has a better M2 factor. Compared with traditional uniform fiber, the long tapered fiber has the advantage of suppressing nonlinear effects and maintaining excellent beam quality. Both the cladding size and core size of the long tapered fiber reported so far vary simultaneously in a constant core-to-cladding diameter ratio (CCDR) along the length. In this work, we propose a technique for preparing cladding uniform core tapered fiber (CUCTF) with a varying CCDR, and have successfully fabricated CUCTF. The core diameters of narrow end and wide end are 31.2 μm and 52.5 μm, respectively. The cladding diameter is always 400 μm along the length. The laser performance of CUCTFs with different structures (wide to narrow, narrow to wide) are investigated based on a co-pumped fiber amplifier. Between them, the CUCTF with the wide to narrow structure has a better M2 factor of 1.455 due to mode filtering. [ABSTRACT FROM AUTHOR]

In recent decades, hypoxic areas have rapidly expanded worldwide in estuaries and coastal zones. The Pearl River Estuary (PRE), one of China's largest estuaries, experiences frequent seasonal hypoxia due to intense human activities and eutrophication. However, the ecological effects of hypoxia in the PRE, particularly on fish communities, remain unclear. To explore these effects, we collected fish community and environmental data in July 2021 during the summer hypoxia development period. The results revealed that bottom‐layer dissolved oxygen (DO) in the PRE ranged from 0.08 to 5.71 mg/L, with extensive hypoxic zones (DO ≤ 2 mg/L) observed. Hypoxia has varied effects on fish community composition, distribution, species, and functional diversity in the PRE. A total of 104 fish species were collected in this study, with approximately 30 species (28.6%) exclusively found in hypoxic areas. Species responses to hypoxia varied: species such as Sardinella zunasi, Coilia mystus, and Nuchequula nuchalis were sensitive, while Decapterus maruadsi, Siganus fuscescens, and Lagocephalus spadiceus showed higher tolerance. Within the hypoxia area, dissolved oxygen was the main limiting factor for fish community diversity. Functional diversity (FDiv) decreased with higher dissolved oxygen levels, indicating a potential shift in the functional traits and ecological roles of fish species in response to changing oxygen conditions. Further analysis demonstrated that dissolved oxygen had a significantly stronger effect on fish community structure at hypoxic sites than in the whole PRE. Moreover, other environmental variables also had significant effects on the fish community structure and interacted with dissolved oxygen in the hypoxia area. These findings suggest that maintaining sufficient dissolved oxygen levels is essential for sustaining fish communities and ecosystem health in the PRE. This study provides novel insights into the effects of hypoxia on fish communities in estuarine ecosystems and has significant implications for the ecological health and management of the PRE. [ABSTRACT FROM AUTHOR]

The temporal and spatial variability of the Antarctic coastline is a clear indicator of change in extent and mass balance of ice sheets and shelves. In this study, the Canny edge detector was utilized to automatically extract high-resolution information of the Antarctic coastline for 2005, 2010, and 2017, based on optical and microwave satellite data. In order to improve the accuracy of the extracted coastlines, we developed the Canny algorithm by automatically calculating the local low and high thresholds via the intensity histogram of each image to derive thresholds to distinguish ice sheet from water. A visual comparison between extracted coastlines and mosaics from remote sensing images shows good agreement. In addition, comparing manually extracted coastline, based on prior knowledge, the accuracy of planimetric position of automated extraction is better than two pixels of Landsat images (30 m resolution). Our study shows that the percentage of deviation (<100 m) between automatically and manually extracted coastlines in nine areas around the Antarctica is 92.32%, and the mean deviation is 38.15 m. Our results reveal that the length of coastline around Antarctica increased from 35,114 km in 2005 to 35,281 km in 2010, and again to 35,672 km in 2017. Meanwhile, the total area of the Antarctica varied slightly from 1.3618 × 107 km2 (2005) to 1.3537 × 107 km2 (2010) and 1.3657 × 107 km2 (2017). We have found that the decline of the Antarctic area between 2005 and 2010 is related to the breakup of some individual ice shelves, mainly in the Antarctic Peninsula and off East Antarctica. We present a detailed analysis of the temporal and spatial change of coastline and area change for the six ice shelves that exhibited the largest change in the last decade. The largest area change (a loss of 4836 km2) occurred at the Wilkins Ice Shelf between 2005 and 2010. [ABSTRACT FROM AUTHOR]

• The radiation induced static mode degradation (SMD) was discovered and studied. • The threshold of SMD could be related with the composition of active fiber and increases with the increase of Ce. • When the Ce concentration increased by 35.5%, SMD threshold rose by 16% at most. We report on an experimental investigation of radiation induced static mode degradation in Yb-Ce co-doped pulsed fiber amplifiers. For investigating the impact of irradiation on beam quality, radiation-darkened fibers were irradiated by gamma rays. The laser properties of three types of fibers were investigated. With the pump power increased, static mode degradation appeared: M2 factor raised significantly and the output beam profile transformed from LP 01 into LP 11 shape without high-frequency component. The threshold of static mode degradation decreased with irradiation dose, and related to Yb-Ce co-doped fiber compositions. The doping of Ce benefits to the improvement of the static mode degradation threshold: in the case of the Ce concentration increasing by 35.5%, SMD threshold rose by 16% at most. [ABSTRACT FROM AUTHOR]

• Fabricate an Yb-doped constant-cladding tapered-core (CCTC) fiber. • Investigate the laser properties of CCTC fiber under different bending schemes. • The output power of CCTC fiber is up to 2.7 kW with a slope efficiency of 82.1%. A constant-cladding tapered-core (CCTC) fiber with the core size varying monotonously along the length was fabricated. The core/cladding diameters of narrow end and wide end are 24/400 μm and 31/400 μm, respectively. A forward-pumping master oscillator power amplifier (MOPA) was constructed to investigate the laser performance of this fiber under two bending schemes (8–14 cm and 12–16 cm). The maximum output power is scaled up to 2704 W with a slope efficiency of 82.1% in the case of bending diameter ranges from 12 cm to 16 cm, the M2 factor at 2548 W output power is 2.16, and no signs of transverse modal instability (TMI) and stimulated Raman scattering (SRS) were observed in whole experiment. The above result verifies the potential of power scalability of CCTC fiber, and the laser performance can be further enhanced by fiber design optimization and other TMI suppression methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fabrication of cyclically amplifying DNA nanomachine. • Fluorescence signal detection through proximity ligation system conjugated with qPCR. • Low detection limits of 0.06 ng/ml. • A good linear relationship with DIG concentrations during the detection range of 0.1 ∼ 5 ng/ml. • Selective DIG detection in human blood serum. A nanobiosensor was prepared by DNA nanomachine based on proximity ligation assay (PLA) for the detection of digoxin (DIG) in serum. In this sensor the DNA nanomachine releases a large number of signal probes (SP) after addition of DIG, which participate in PLA as the connector strand, initiating real-time quantitative polymerase chain reaction (qPCR) and producing fluorescence signals. For the benefit of clinical therapeutics, we determined the detection range of 0.1 ∼ 5 ng/mL. Under the optimal experimental conditions, the cycle threshold (Ct) value showed a good linear relationship with DIG concentrations, and the detection limit was as low as 0.06 ng/mL (3σ). This method achieved the ultrasensitive detection of DIG by signal amplification and was successfully used for the detection of DIG in real serum, which has a good potential for application in the field of therapeutic drug monitoring. [ABSTRACT FROM AUTHOR]

In data-sparse regions such as the Arctic, atmospheric reanalysis is one of the key tools for understanding rapid climate change at the regional and global scales. The utility of reanalysis datasets based on data assimilation is affected by their accuracy and biases. Therefore, it is important to evaluate their performance. Here, we conduct inter-comparisons of two temperature variables, namely, the 2-m air temperature (Ta) and the surface temperature (Ts), from the widely used ERA-I and ERA5 reanalysis datasets provided by the European Centre for Medium-Range Weather Forecasts (ECMWF) against in situ observations from three international buoy programs (i.e., the International Arctic Buoy Programme (IABP), the Multidisciplinary Drifting Observatory for the Study of Arctic Climate (MOSAiC), and the Cold Regions Research and Engineering Laboratory (CRREL)) during 2010–2020 in the Arctic. Overall, the results show that both the ERA-I and ERA5 were well correlated with the buoy observations, with the highest correlation coefficient reaching 0.98. There were generally warm Ta biases for both ERA-I (2.27 ± 3.33 °C) and ERA5 (2.34 ± 3.22 °C) when compared with more than 3000 matching pairs of daily buoy observations. The warm Ta biases of both reanalysis datasets exhibited seasonal variations, reaching the maximum of 3.73 ± 2.84 °C in April and the minimum of 1.36 ± 2.51 °C in September. For Ts, both ERA-I and ERA5 exhibited good consistencies with the buoy observations, but have higher amplitude biases compared with those for Ta, with generally negative biases of −4.79 ± 4.86 °C for ERA-I and −4.11 ± 3.92 °C for ERA5. For both reanalysis datasets, the largest bias of Ts (−11.18 ± 3.08 °C) occurred in December, while the biases were rather small (less than −3 °C) in the warmer months (April to October). The cold Ts biases for ERA-I and ERA5 were probably overestimated due to the location of the surface temperature sensors on the buoys, which may have been affected by snow cover. Both the Ta and Ts biases varied for different buoy programs and different sea ice concentration conditions, yet they exhibited similar trends. [ABSTRACT FROM AUTHOR]

Syngnathid fishes (seahorses and pipefish) are unique in reproduction, with males becoming pregnant and giving birth. The brood pouch provides osmoregulation, gas exchange, waste transport, immunoprotection and nutrition supply. However, the function of hormone trafficking is rarely studied. By injecting the mixture liquor of human chorionic gonadotrophin (HCG, 2 IU/g) and luteinizing hormone-releasing hormone A3 (LHRH-A 3, 5 ng/g) into the brood pouch of Hippocampus erectus , we found the reproductive interactions accelerated dramatically, and 4 pairs were successfully mated. After 24 h, the inner epithelium was highly folded and the loose connective tissue layer was highly distended. In the inner tissue layer of the brood pouch, fibroblasts secreted vigorously, blood vessels multiplied and expanded, indicating the physiological structure of the brood pouch modified hastily from the unpregnant stage to the progravid phase. Correspondingly, transcriptome results revealed the gene expression of circadian, epitheliogenesis, angiogenesis, lipid transfer, and spermiogenesis were significantly up-regulated. We innovatively found that macromolecule exogenous hormone (HCG) can be not only efficiently transported from brood pouch to body, but also promote mating and the physiological changes of the brood pouch. • HCG and LHRH-A 3 can promote the reproduction of seahorses and accelerate inner epithelium folding, loose connective tissue layer distending and blood vessels multiplying in the brood pouch. • The brood pouch epithelium of seahorses and the mucosal lining of the uterus may belong to the analogous organ. [ABSTRACT FROM AUTHOR]

Owing to the hypoxia status of the tumor, the reactive oxygen species (ROS) production during photodynamic therapy (PDT) of the tumor is less efficient. Herein, a facile method which involves the synthesis of Mg–Mn–Al layered double hydroxides (LDH) clay with MoS2 doping in the surface and anionic layer space of LDH was presented, to integrate the photo-thermal effect of MoS2 and imaging and catalytic functions of Mg–Mn–Al LDH. The designed LDH-MoS2 (LMM) clay composite was further surface-coated with bovine serum albumin (BSA) to maintain the colloidal stability of LMM in physiological environment. A photosensitizer, chlorin e6 (Ce6), was absorbed at the surface and anionic layer space of LMM@BSA. In the LMM formulation, the magnetic resonance imaging of Mg–Mn–Al LDH was enhanced thanks to the reduced and acid microenvironment of the tumor. Notably, the ROS production and PDT efficiency of Ce6 were significantly improved, because LMM@BSA could catalyze the decomposing of the overexpressed H2O2 in tumors to produce oxygen. The biocompatible LMM@BSA that played the synergism with tumor microenvironment is a promising candidate for the effective treatment of cancer. [ABSTRACT FROM AUTHOR]

Multifunctional nanomaterials for cancer therapy has attracted researchers' attention for decades. In this study, a unique oxidative method using KMnO4 or K2MnO4 as oxidizing agents to oxidize dopamine (DA) to polydopamine (PDA) was reported. The oxidizing agent was reduced to MnOx to form MnOx/PDA composite NPs. Afterwards, the MnOx/PDA composite NPs were surface‐modified with bovine serum albumin (BSA) to form a multifunctional theranostic agent, named MnOx/PDA@BSA NPs, with improved colloidal stability and biocompatibility. Such a material would become a photothermal nanoagent, since the PDA renders the composite NPs an admirable photothermal transforming ability with the photothermal conversion efficiency of 27.06%. Meanwhile, as a commonly used T1 contrast agent, manganese (Mn2+) endowed the MnOx/PDA@BSA NPs with MRI ability, rendering the as‐synthesized MnOx/PDA composite NPs a capability of imaging guided multi‐modal tumor therapy. Moreover, the formed MnOx/PDA@BSA NPs were used for drug loading, which was found to own the tunable drug loading and controlled drug releasing capacity. The as‐prepared composite NPs were successfully used for the combined tumor chemotherapy and photothermal therapy in vitro and in vivo. This research provides insights into the development of conjugated polymer‐based nanomaterial for various biomedical applications, especially in imaging guided cancer therapy. [ABSTRACT FROM AUTHOR]

• The contribution of oyster reefs characteristics to the omnivorous fish intestinal microbiota was distinct. • Microbial communities in the oyster reefs and fish intestines showed various predictive functions and unique core indicators. • The microbial diversity in sediments were significantly higher than that in intestines. The habitats of oyster reefs had played various ecological services functions, as an important means of marine ecological restoration and fishery resources conservation, which had been widely used worldwide. And the characteristics of microbial communities would be inevitably affected by habitat of oyster reefs. The aim of this study was to reveal the relationship between oyster reefs and the intestinal microbiota of fish (Takifugu ocellatus , Acanthopagrus latus , Clupanodon thrissa , and Mugil cephalus). Here, based on 16S rRNA sequencing, this research analyzed the microbial communities of fishes gut in the oyster reefs from the most crucial estuary economic zone in Southern China. It was significantly lower that the bacterial alpha-diversity in the fish intestines than in the sediments of oyster reefs. The non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) results showed that intestines microbiota of T. ocellatus and A. latus were more homologous to sediments microbiota, but intestines microbiota of C. thrissa and M. cephalus were more similar to the water microbiota. There were obvious differences in the contribution of oyster reefs habitat to intestinal microorganisms of four fishes. Source tracking analysis as well reached the similar conclusion. For instance, contribution of water to T. ocellatus and A. latus was lesser than sediments, which was related to their benthic habits. Based on the differences in microbial community compositions, the functional prediction analysis had demonstrated that special functional pathways and independent core indicators had been formed separately from oyster reefs and fish intestines. Overall, these findings highlighted the characteristics of microbial diversity and functions from the omnivorous fish living in oyster reefs habitats. This research proposed new insights into the function of oyster reefs habitats, which have enriched the ecological service value of oyster reefs from microbial ecology and provided a reference for the application of oyster reefs habitats in other estuaries. [ABSTRACT FROM AUTHOR]

• We first presented all-fiber cascaded combiners for ARM beam laser with a flattop central beam. The cascaded combiners are consist of a 3×1 combiner and a (6+1)×1 combiner in series. • By selecting appropriate structural parameters of the cascaded combiners, the first 3 × 1 combiner can form a multi-mode laser beam, which is input to the center port of the second (6 + 1) × 1 combiner to obtain an ARM beam with a uniformly distributed central beam. • The cascaded combiners yield an 8.8 kW central output laser with a transmission efficiency of 96.2 % and M2 factor of 5.24, as well as a ring output laser with an average efficiency higher than 98 %. An all-fiber structure that obtains an adjustable-ring mode (ARM) beam with a uniformly distributed central beam is put forward for the first time based on the beam combining technology. This structure is all-fiber cascaded combiners consisting of a 3 × 1 combiner and a (6 + 1) × 1 combiner in series. A multi-mode fiber with core diameter of 50 µm acts as the connective fiber, transmitting the combined laser of the first 3 × 1 combiner into the center guide core of the output fiber by the well-designed (6 + 1) × 1 combiner. Through the independent transmission of the center and ring beams, an 8.8 kW uniformly distributed central output laser with a transmission efficiency of 96.2 % and M2 of 5.24 is obtained by the cascaded combiners. The feasibility of ARM laser beam with a 10 kW-level flattop central beam provides a new approach for high-power laser welding. [ABSTRACT FROM AUTHOR]

• Present the first experimental results about the relationship between the Modal degradation (MD) and stimulated Brillouin scattering (SBS) in high-power continuous-wave (CW) narrow-linewidth (NL) linearly polarized fiber amplifiers. • For the first time, the time-frequency domain information analysis is added to the SBS and MD phenomena in the experiment, and the relationship between SBS and MD is completely studied in combination with the beam quality analyzer. • A near-diffraction-limited output beam without MI is achieved up to 760 W with M2 x = 1.09 and M2 y = 1.08, and polarization extinction ratio (PER) > 19 dB. In our high-power continuous-wave (CW) narrow-linewidth linearly polarized master oscillator power amplifier (MOPA) system, the mode degradation (MD) induced by stimulated Brillouin scattering (SBS) was observed. In the experiments, the beam quality maintained LP01 mode until the onset of SBS, and significantly deteriorated with the surging of SBS. Once the method of suppressing SBS was implemented, such as linewidth broadening and polarization extinction ratio (PER) weakening of the seed laser, the output laser mode recovered to fundamental mode, revealing the MD effect was evidently mitigated. Meanwhile, the associated relationship between MD and SBS was also investigated based on the analysis of spectrum, oscilloscope, and beam quality. [ABSTRACT FROM AUTHOR]

Breast milk, as the most ideal food for infants, contains the main nutrients to meet the growth and development of infants. Lactose is an essential energy source in breast milk, the concentration of which varies based on a variety of circumstances, including maternal diet and lactation stage. Studies demonstrated that lactose content could affect the development of the brain and gut immunity of infants. We integrated the enzyme cascade reaction with colorimetry, and then established a data-prediction model utilizing multi-point absorbance analysis and a back-propagation (BP) neural network. Lactose underwent an enzymatic cascade to generate H 2 O 2, which oxidized the chromatic substrate 3,3′5,5′-tetramethylbenzidine (TMB). Absorbance at several time intervals and wavelengths was measured. Different from the traditional end-point detection methods and their single input data model, the absorbance data were detected at various time points and then fitted by BP neural network in this research. The detection of lactose in breast milk showed an average recovery rate of 99.14%. Meanwhile, our strategy is time-efficient and required no complex sample preparation processes. The robust nonlinear mapping and high fault tolerance of the BP neural network significantly enhances the stability and precision of the colorimetric analysis. Overall, this approach may be used for low-cost, convenient, and accurate lactose quantification in breast milk. [Display omitted] • A convenient, fast and low-cost method for the detection of lactose in breast milk. • Novel combined dynamic detection with multi-input nature of BP neural networks. • This study model had a better predicted performance of lactose concentration. [ABSTRACT FROM AUTHOR]

• W-type fiber design to improve Q-switched Yb-doped fiber lasers (YDFLs) is proposed. • A fiber was fabricated by employing modified chemical vapor deposition. • The Yb-doped W-type fiber exhibited enhanced beam quality and output spectra. We report a W-type fiber design for improving the beam quality and spectral purity of the Q-switched Yb-doped fiber lasers (YDFLs). Our W-type fiber exhibited higher losses in the high order modes (>100 dB/m) and lower losses in the fundamental modes (<0.1 dB/m). A 20/130 μm Yb-doped W-type fiber was fabricated by employing a modified chemical vapor deposition (MCVD) process and a solution-doping technique. The Yb-doped W-type fiber was examined in an acousto-optic Q-switched YDFL. A robust single-mode operation with a 1.19 M2 factor was obtained by optimizing the bending radii. The suppression of mixed mode four-wave mixing (FWM) and amplified spontaneous emission (ASE) was observed in the output spectral with an 18 dB signal to noise ratio (SNR) enhancement at 1064 nm and a 5.3 dB ASE inhibition ratio at 1030 nm. The Yb-doped W-type fiber exhibited enhanced beam quality and output spectra than the conventional Yb-doped step-type refractive index fiber. Therefore the W-type fiber suits the Q-switched fiber laser applications. [ABSTRACT FROM AUTHOR]

• A multi-dimensional functional space was built to visualize the functional structure. • The functional structure and trait composition of fish in the PRE vary seasonally. • The CWM traits were mainly affected by temperature, DO, chlorophyll-a, and depth. Estuaries are one of the most important ecosystems with high biological productivity. They connect freshwater and marine ecosystems, and the fish community assemblages face intense environmental changes, so estuarine fish communities have unique ecological characteristics. With the increase of human activities and the discharge of pollutants, the pressure on the ecosystem of the Pearl River Estuary (PRE) is intensifying, and its ecosystem functions and services are inevitably affected. To better understand the functional structure of the fish community in the PRE and its response to environmental changes, we analyzed the trait composition of the community and its relationships to environmental factors based on 10 functional traits of 130 fish species collected in the PRE during the summer and winter of 2020–2021. In addition, we built a multi-dimensional functional space to visualize the overall functional structure of the PRE and explore the seasonal variation of the selected traits in the functional space. Our findings suggest that the functional traits of the fish communities in the PRE were mainly affected by temperature, dissolved oxygen, chlorophyll-a, and depth. Among them, the effects of dissolved oxygen, temperature, and chlorophyll-a on CWM traits were reflected in seasonal differences, while the effects of depth were reflected in spatial differences. We also found the main trait categories that occupied the most functional space and contributed the most to the seasonal differences in functional space. The results of this study are significant for understanding the seasonal variation of the functional structure in the PRE and how environmental gradients drive the functional traits of fish communities, and also provide insights for effective ecosystem-based management in the PRE. [ABSTRACT FROM AUTHOR]

• The stochastic pulses and temporal optical rogue waves (RWs) behavior are observed and investigated in the high power short-cavity Yb-doped random fiber laser (YDRFL) for the first time. • The record output power without the stimulated Raman scattering (SRS) is promoted to 26.6 W in the YDRFL with the Ge-doped fiber (GDF) length of 120 m. • The experimental results manifest that the proportion of RWs depends on the GDF length and can also affect the stability of output lasing and the M2 factor distribution. • The experimental phenomenons display that the multiple high order SRS stokes lights and the visible light radiations are generated in the YDRFL with shorter GDF length. • The research results reveal that achieving the relative stable output power requires the greater pump power for the shorter GDF length. A high power short-cavity random fiber laser employing the gain mechanism of the Yb-doped fiber and the half-open cavity structure and the temporal optical rogue waves (RWs) behavior are observed and investigated in the paper. The record output power without the stimulated Raman scattering (SRS) is promoted to 26.6 W in the Yb-doped random fiber lasers (YDRFL) with the Ge-doped fiber (GDF) length of 120 m. The stochastic pulses and temporal optical RWs are observed and demonstrated in the short cavity YDRFL for the first time. It is found that the proportion of RWs depends on the GDF length and can also affect the stability of output lasing and the M2 factor distribution. The M2 factor distribution demonstrated a special longitudinal mode instability phenomenon. The experimental phenomenons display that the multiple high order SRS stokes lights and the visible light radiations are generated by the soliton self-frequency shift and Cherenkov radiation in the YDRFL with shorter GDF length. The research results reveal that achieving the relative stable output power requires the greater pump power for the shorter GDF length, although decreasing the GDF length will promote the maximum output power of the YDRFL without the SRS. [ABSTRACT FROM AUTHOR]

Although anaplasmosis cases have been nationally identified in China, no human isolates of A. phagocytophilum have been obtained, which limits the analysis of any molecular and genetic contributions to patients' severe clinical manifestations and the study of the bacteria's pathogeneses in China. Given this situation, a joint project was conducted in 2009–2010. A total of 421 febrile cases of unknown etiology were collected and the patients' blood samples were collected for laboratory diagnoses including serologic diagnosis based on the four-fold rise in the anti- A. phagocytophilum IgG titer by indirect micro-immunofluorescence assay (IFA), positive PCR assay and confirmation of A. phagocytophilum DNA and positive culture of A. phagocytophilum and confirmed by amplification and sequencing of the 16S rRNA and ank A genes of the A. phagocytophilum isolates. A total of 570 ticks were collected from the patients' domestic animals (456) and from wild fields (114) for culturing and amplifying and sequencing the 16S rRNA gene of A. phagocytophilum. Phylogenetic analyses were performed on the 16S rRNA and ank A gene sequences of the isolates and the ticks tested in the study. A total of 46 (10.9%) confirmed and 16 (3.8%) probable cases were diagnosed and severe clinical features and higher mortality rates were observed in these Chinese patients. Five isolates were obtained and the 16S rRNA genes of the 5 isolates were conserved but variety for ank A genes. Two human isolates and 1 tick isolate from Shandong Peninsula, where all patients exhibited severe clinical manifestations, were grouped as one clan based on the phylogenetic analyses, while 2 other human isolates were clustered in a second clan. 43.5% of H. longicornis were infected with A. phagocytophilum.The present study is the first to obtain clinical isolates of A. phagocytophilum in China. The diversity of the ank A genes of Chinese isolates will help us to further discern the relationship between the variations in the ank A genes and the severity of the disease's clinical manifestations in China. [ABSTRACT FROM AUTHOR]

• There are great differences in expression profiles and signal pathways between clinical primary and metastatic osteosarcoma. • Disease classification can assist clinical differential diagnosis and further individualized precision treatment. • Ginsenoside Rh2 could affect cellular molecules on the basis of a structural model and by intervening with the process of OS. • Ginsenoside Rh2 acts as a suppressor of OS proliferation and migration and promotes early apoptosis. • Ginsenoside Rh2 shows promising application potential for suppressing OS in an MAPK- and PI3K/Akt/mTOR-dependent manner. This study aimed to compare the gene expression variation of clinical primary osteosarcoma (OS) and metastatic OS, identify expression profiles and signal pathways related to disease classification, and systematically evaluate the potential anticancer effect and molecular mechanism of ginsenoside Rh2 on OS. A raw dataset (GSE14359), which excluded GSM359137 and GSM359138, was downloaded from the Gene Expression Omnibus. Differentially expressed genes (DEGs) and principal component analysis (PCA) were obtained with limma. Pathways enrichment analysis was understood by GSEA app. Rh2-associated targets were harvested and mapped through PharmMapper and Cytoscape 3.4.0. The toxicity of Rh2 was determined using crystal staining and MTT assay on 143B and MG63 cell lines. The relative protein expression was confirmed through Western blot analysis. The mitochondrial membrane potential (△Ψm) was evaluated by JC-1 fluorescence staining. The cell mobility was measured via wound healing and transwell assays. A total of 752 genes were upregulated, while 161 genes were downregulated. GSEA and PCA displayed significant function enrichment and classification. Through PharmMapper and Cytoscape 3.4.0, Rh2 was found to target the mitogen activated protein kinase (MAPK) and PI3K signaling pathways, which are the key pathways in the metastasis of OS. Furthermore, Rh2 induced a concentration-dependent decrease in cell viability and early apoptosis associated with ΔΨm decline, while a non-lethal dose of Rh2 weakened the metastatic capability. Moreover, systematic evaluation showed that promoting the MAPK signaling pathway and inhibiting PI3K/Akt/mTOR were correlated with the anticancer effects of Rh2 on metastatic OS. In conclusion, transcriptome-derived approaches may be beneficial in diagnosing early metastases, and Rh2, a multi-targeting agent, shows promising application potential in suppressing metastatic OS in an MAPK- and PI3K/Akt/mTOR-dependent manner. [ABSTRACT FROM AUTHOR]

The Northwest Passage (NWP) in the Arctic is usually covered with hazardous multi-year ice (MYI) and seasonal first-year ice (FYI) in winter, with possible thin ice and open-water areas during transition seasons. Ice classification is important for both marine navigation and climate change studies. Satellite-based Synthetic Aperture Radar (SAR) systems have shown advantages of retrieving this information. Operational ice mapping relies on visual analysis of SAR images along with ancillary data. However, these maps estimate ice types and concentrations within large-size polygons of a few tens or hundreds of kilometers, which are subjectively identified and selected by analysts. This study aims at developing an automated algorithm to identify individual MYI floes from SAR images then classify the rest of the image as FYI and other ice types. The algorithm identifies the MYI floes using extended-maximum operator, morphological image processing, and a few geometrical features. Classifying the rest of the image uses texture and neural network model. The input data is a set of Sentinel-1 A/B Extended Wide (EW) mode images, acquired between September and March 2016–2019. Although the overall accuracy (for all type classification) from the new method scored 93.26%, the accuracy from using the texture classifier only was 75.81%. The kappa coefficient from the former was higher than the latter by 0.25. Compared with the operational ice charts from the Canadian Ice Service, ice type maps from the new method show better distribution of MYI at the fine scale of individual floes. Comparison against MYI concentration from two automated algorithms that use a combination of coarse-resolution passive and active microwave data also confirms the advantage of resolving MYI floes from the fine-resolution SAR. [ABSTRACT FROM AUTHOR]

Background: Host genetic factors may play a role in the occurrence and progress of SARS-Cov infection. This study was to investigate the relationship between tumor necrosis factor (TNF)-alpha gene polymorphisms with the occurrence of SARS-CoV infection and its role in prognosis of patients with lung interstitial fibrosis and femoral head osteonecrosis.Methods: The association between genetic polymorphisms of TNF-alpha gene and susceptibility to severe acute respiratory syndromes (SARS) was conducted in a hospital-based case-control study including 75 SARS patients, 41 health care workers and 92 healthy controls. Relationships of TNF-alpha gene polymorphisms with interstitial lung fibrosis and femoral head osteonecrosis were carried out in two case-case studies in discharged SARS patients. PCR sequencing based typing (PCR-SBT) method was used to determine the polymorphisms of TNF-alpha gene in locus of the promoter region and univariate logistic analysis was conducted in analyzing the collected data.Results: Compared to TT genotype, the CT genotype at the -204 locus was found associated with a protective effect on SARS with OR(95%CI) of 0.95(0.90-0.99). Also, TT genotype, CT and CC were found associated with a risk effect on femoral head necrosis with ORs(95%CI) of 5.33(1.39-20.45) and 5.67(2.74-11.71), respectively and the glucocorticoid adjusted OR of CT was 5.25(95%CI 1.18-23.46) and the combined (CT and CC) genotype OR was 6.0 (95%CI 1.60-22.55) at -1031 site of TNF-alpha gene. At the same time, the -863 AC genotype was manifested as another risk effect associated with femoral head necrosis with OR(95%CI) of 6.42(1.53-26.88) and the adjusted OR was 8.40(95%CI 1.76-40.02) in cured SARS patients compared to CC genotype.Conclusion: SNPs of TNF-alpha gene of promoter region may not associate with SARS-CoV infection. And these SNPs may not affect interstitial lung fibrosis in cured SARS patients. However, the -1031CT/CC and -863 AC genotypes may be risk factors of femoral head necrosis in discharged SARS patients. [ABSTRACT FROM AUTHOR]