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Single-pixel detecting is suitable for wavefront reconstruction in some special wavelengths where array detectors are immature or even unavailable and/or under low light conditions. However, most of the demonstrations are generally realized by multi-step phase-shifting interferometry with a liquid crystal spatial light modulator (LC-SLM) that has a slow modulation speed, which limits the reconstruction speed, thus restricting practical applications of the technique. Here, we propose to use a digital-micromirror-device-(DMD)-based single-pixel off-axis common-path interferometry (SOCI) for faster wavefront reconstruction. The method utilizes passive detection based on the DMD to realize SOCI for accelerating wavefront reconstruction. As compared to the LC-SLM-based phase-shifting techniques, since the modulation speed of the DMD is hundreds of times faster than that of the LC-SLM, the DMD-based SOCI accelerates several folds of reconstruction speed further, which, thus, makes the final wavefront reconstruction three orders of magnitude faster. The effectiveness and advantages of our method are experimentally demonstrated by quantitatively reconstructing the amplitude and phase images of a biological sample. [ABSTRACT FROM AUTHOR]

The radiogenic isotope compositions of strontium (Sr) and neodymium (Nd) on the surface of the Earth are powerful tools for tracing dust sources and sinks on the Earth's surface. To differentiate between the spatial variabilities in eolian dust sources in key cryospheric regions at the three poles (the Arctic; Antarctica; and the "third pole", covering the high mountainous area in Asia), a dataset of Sr–Nd isotopic compositions from extremely cold or arid terrestrial environments was compiled, similar to the method of Blanchet (2019). The database includes Holocene and Quaternary snow, ice, sand, soil (loess), sediment, and rock samples from the three poles based on 90 different references and our own measurement data, with a total of 1989 data points, comprising 206 data points with different grain sizes and 212 data points with fraction measurements. There are 485 data points from the third pole, 727 data points from the Arctic, and 777 data points from Antarctica. The sampling and measurement methods of these data are introduced. For each pole, geographical coordinates and other information are provided. The main scientific purpose of this dataset is to provide a Sr–Nd dataset based on collective documentation and our own measurements, which will be useful for determining the sources and transport pathways of dust in snow, ice, rivers, and oceans at or near the three poles as well as to investigate whether multiple dust sources are present at each of the poles. This dataset provides exhaustive detailed documentation of the isotopic signatures at the three poles during specific time intervals in the Quaternary period, which are useful for understanding the sources or sinks of eolian dust and sediments at the three poles. The dataset is available from the National Tibetan Plateau Data Center (10.11888/Cryos.tpdc.272100, Du, 2022). [ABSTRACT FROM AUTHOR]

Simple Summary: The nutritional needs of mink and foxes have long been clear, not specifically for blue foxes. With the development of technology, the present study aimed to study the effect of dietary calcium, phosphorus, and vitamin D3 supplementation levels on the growth performance, nutrient digestibility, and serum biochemical indicators of the growing hairy blue fox. The results showed that Ca (0.8–1.2%) and vitamin D3 (1327 IU·kg−1) doses have important effects on the growth performance and nutrient digestibility of growing blue foxes and can reduce fecal nitrogen and fecal phosphorus by improving the utilization of protein and phosphorus. A 3 × 3 factorial experiment was conducted to investigate the influence of dietary calcium, phosphorus, and vitamin D3 (VD3) supplement levels on the growth performance, nutrient digestibility, and serum biochemical indices of growing-furring blue foxes. One hundred and thirty-five 120-day-old male blue foxes were randomly allocated into nine groups. The nine treatment diets were supplemented with 0%, 0.4%, or 0.8% Ca, and 1000, 2000, or 4000 IU·kg−1 VD3. The base diet contained 0.8% Ca and 327 IU·kg−1 VD3. The dietary calcium level had a significant effect on the average daily gain (ADG) of blue foxes at 121 to 135 days of age and 136 to 150 days (p < 0.05). The ADG of blue foxes at 121 to 135 days of age was significantly decreased by VD3 level (p < 0.05). The Ca dosage decreased the nutrient digestibility (p < 0.05). The Ca dosage increased the fecal Ca and P and decreased the P digestibility (p < 0.05). Interactions were found between the Ca and VD3 levels, which affected the digestibility of Ca and P (p < 0.05). In conclusion, this research determined the suitable doses of Ca and VD3 for growing-furring blue foxes. [ABSTRACT FROM AUTHOR]

• Simultaneously amplitude and phase (i.e. spatial wavefront) imaging of a biological sample via DMD-based single-pixel phase-shifting interferometric techniques is demonstrated. • The experimental performances of those techniques for wavefront imaging of a biological sample are quantitatively and comprehensively compared, when different orthogonal bases, different reference strategies, and different modulation methods (i.e. binary grating, Lee, and super-pixel methods) are employed there. • Experimental results suggest that the grating-phase-shifting-based SWI using Hadamard basis (G-HSWI) performs best, in which one can use the checkerboard reference for the maximum field of view or select the peripheral reference for a better imaging resolution. • 2fps dynamic wavefront imaging of the sample at a 10 % downsampling rate with a resolution of 128 × 128 pixels can be realized by G-HSWI. Single-pixel wavefront imaging (SWI) is an innovative technique for simultaneously measuring the amplitude and phase of an unknown field, which is particularly important for wavefront imaging in invisible wavelengths and under low light conditions. However, most of the existing SWI techniques are still in the technical development stage. Here, we provide a comprehensive analysis and comparison of the SWI methods using DMD-based single-pixel multi-step phase-shifting interferometric techniques. Through experimental demonstrations, we first compare the performances of the techniques using the Hadamard basis, Fourier basis, and discrete cosine transform (DCT) basis. Further, the performances of the Hadamard basis-based SWI (HSWI) technique using phase-shifting interferometry with the different reference strategies are investigated while the binary grating, Lee, and super-pixel methods are applied to control the DMD for realizing the necessary complex amplitude modulations there. Experimental results suggest the grating-phase-shifting-based HSWI performs best, in which one can use the checkerboard reference for the maximum field of view or select the peripheral reference for a better imaging resolution; and it can do 2 fps wavefront imaging of the sample at 10 % downsampling rate with a resolution of 128 × 128 pixels. Our work provides researchers with a guideline to choose a suitable SWI technique for their applications. [ABSTRACT FROM AUTHOR]

Simple Summary: Nutrient requirements have previously been established for minks and foxes, but not specifically for blue foxes. Over the past thirty years, an increase in body size was observed in the farmed blue fox because of the development of modern breeding technology. Hence, it is necessary to study the interaction mechanisms and requirements of calcium (Ca) and vitamin D3 (VD3) according to the body weights and conditions of farmed blue foxes to guide modern farms. The objective of the present study was to study the influence of dietary Ca and VD3 supplemental levels on the nutrient digestibility, growth performance, and serum biochemical indices of growing blue foxes. The results indicated that the Ca and VD3 doses showed promising effects on growth performance and nutrient digestibility in growing blue foxes and could reduce fecal nitrogen (N) and phosphorus (P) via improvement in protein and P utilization. Based on the randomized design, a 3 × 3 factorial experiment was designed to examine the effects of dietary calcium (Ca), phosphorus (P), and vitamin D3 (VD3) supplemental levels with a fixed 1.5/1 ratio of Ca to P on the growth performance, nutrient digestibility, and serum biochemical indices blue foxes' growth. In total, 135 male blue foxes with the age of 60 days were randomly divided into 9 groups each with 15 blue foxes. The blue foxes belonging to the nine treatment groups were fed Ca supplementation (0%, 0.4%, or 0.8%) and VD3 supplementation (1000, 2000, or 4000 IU/kg DM). The base diet contained 0.8% Ca and 327 IU/kg VD3. The dosage of VD3 in blue foxes showed a significant impact on their growth performance (p < 0.05). The Ca dosage had a linear effect on the digestibility of the CP and carbohydrates (CHO) (p < 0.05). In conclusion, the results indicated that the Ca and VD3 doses showed promising effects on growth performance and nutrient digestibility in growing blue foxes and could reduce fecal N and P via improvement in protein and P utilization. [ABSTRACT FROM AUTHOR]

Identifying the mechanism for sex determination in amphibians is challenging. Very little is known about sex determination mechanisms of Rana dybowskii, a species of importance to evolutionary and conservation biology. We screened for sex‐linked molecular markers in R. dybowskii in China using target region amplification polymorphism with 2 fixed primers against the sequences of Dmrt1. We found 2 male‐linked molecular markers in R. dybowskii, which were 222 bp and 261 bp long. The detection rates of 222 bp marker in males form Xinglong, Huadian, and Dandong were 93.79%, 69.64%, and 13.64%, respectively, while the rate in females from Huadian was 27.50%. Besides, the detection rates of 261 bp marker in the above 3 regions were only observed in males at the rate of 93.79%, 87.50%, and 32.73%, respectively. The inheritance patterns of sex‐linked molecular markers showed that the 2 sex‐linked molecular markers were heterozygous. Compared to the XY‐male parent, progeny from XX‐pseudo‐male parent possessed lower sex reversal ratio at the same rearing temperature, and the proportion of female froglets from an XX‐pseudo‐male parent was more than 95% at low rearing temperature (15°C). Our findings suggest that R. dybowskii displays male heterogamety, and the 2 sex‐linked molecular markers may have a guiding significance for the protection and utilization of R. dybowskii. [ABSTRACT FROM AUTHOR]

Thermokarst lakes and ponds (hereafter referred to as thaw lakes) play an important role in the permafrost regions by regulating hydrology, ecology, and biogeochemistry. However, detailed quantitative information on thaw lake extent and distribution remains poorly resolved across the entire permafrost regions on the Qinghai‐Tibet Plateau (QTP). Here, we applied the random forest (RF) model and manual visual vectorization methods to extract thaw lake boundaries on the QTP based on Sentinel‐2 images. Accuracy assessment was comprehensively demonstrated regarding the inherent spatial resolution of imagery and RF model performance. The results showed that the accumulated uncertainty of the total thaw lake area was ±5.75 km2, and the mean accuracy (91.9%) from field‐measured boundaries of 132 thaw lakes supported the accuracy of this inventory. A total of ∼161,300 thaw lakes with sizes ranging from 500 m2 to 3 km2 were detected, with a total area of ∼2,825.45 ± 5.75 km2. Most thaw lakes were detected in the continuous permafrost type (94.1%) and within the elevations of 4,500–5,000 m (68.4%). The small thaw lakes (<10,000 m2) predominated the total lake number (78.9%) but contributed to a small portion of the total lake area (12.7%). Spatial distributions of thaw lakes in terms of different climatic and environmental conditions were also comprehensively explored, including temperature, precipitation, ground thermal stability, active layer thickness, vegetation, soil properties, and underground ice content. This inventory is expected to be incorporated into Earth system models for a more comprehensive projection of the large‐scale biogeochemical feedback of thermokarst landforms on the QTP under continued global warming. Plain Language Summary: Thaw lakes develop when warming soil melts ground ice, causing the surface to collapse and form pools of water. Such lakes can greatly influence local water resources and ecosystems, but also are important sources of greenhouse gas released into the atmosphere. Using Sentinel‐2 images, we provided robust information of thaw lake numbers, areas, and spatial distributions across the entire QTP permafrost regions by applying the random forest model and manual visual vectorization methods. The accuracy of the data set has been demonstrated in regard to the image spatial resolution, model performance, and field‐measured results. Within sizes ranging from 500 m2 to 3 km2, we extracted ∼161,300 thaw lakes with a total area of ∼2,825.45 ± 5.75 km2. We found that most thaw lakes were located in the continuous permafrost regions and within the elevations of 4,500–5,000 m. Most thaw lake sizes were smaller than 10,000 m2 but they only contributed to a little percentage of the total lake area. We also comprehensively explored the spatial distributions of thaw lakes in different climatic and environmental areas. This inventory would be useful for future Earth system models to predict the large‐scale biogeochemical feedback of thaw lakes on the Qinghai‐Tibet Plateau in the future. Key Points: Using Sentinel‐2 images, we established an inventory data set of thaw lakes on the QTP via random forest model and manual postprocessing methodsApproximately 161,300 thaw lakes with sizes ranging from 500 m2 to 3 km2 were extracted, with a total area of ∼2,825.45 ± 5.75 km2Distributions of thaw lakes were highly uneven in regard to different geospatial, climatic and environmental status [ABSTRACT FROM AUTHOR]

Mineral dust can indirectly affect the climate by supplying bioavailable iron (Fe) to the ocean. Here, we present the records of dissolved Fe (DFe) and total Fe (TDFe) in North Greenland Eemian Ice Drilling (NEEM) ice core over the past 110 kyr BP. The Fe records are significantly negatively correlated with the carbon-dioxide (CO2) concentrations during cold periods. The results suggest that the changes in Fe fluxes over the past 110 kyr BP in the NEEM ice core are consistent with those in Chinese loess records because the mineral-dust distribution is controlled by the East Asian deserts. Furthermore, the variations in the dust input on a global scale are most likely driven by changes in solar radiation during the last glacial–interglacial cycle in response to Earth's orbital cycles. In the last glacial–interglacial cycle, the DFe/TDFe ratios were higher during the warm periods (following the post-Industrial Revolution and during the Holocene and last interglacial period) than during the main cold period (i.e. the last glacial maximum (LGM)), indicating that the aeolian input of iron and the iron fertilization effect on the oceans have a non-linear relationship during different periods. Although the burning of biomass aerosols has released large amounts of DFe since the Industrial Revolution, no significant responses are observed in the DFe and TDFe variations during this period, indicating that severe anthropogenic contamination has no significant effect on the DFe (TDFe) release in the NEEM ice core. [ABSTRACT FROM AUTHOR]

• Significant CH 4 accumulation in winter were found in thermokarst lakes on the TP. • The ice-melt period is critical for evaluating thermokarst lake CH 4 and CO 2 fluxes. • Lake depth determines the magnitude of methane flux during ice-melt period. • Snowfall events may accelerate gas release during the ice-melt period. The magnitudes of annual CO 2 and CH 4 emissions from thermokarst lakes and ponds are uncertain due to scarce measurements on the Tibetan Plateau (TP) and limited data on emissions during ice-melt. To evaluate the importance of CO 2 and CH 4 emissions during late winter and spring among the whole year, surface water CO 2 and CH 4 concentrations were measured with the headspace method in ten thermokarst lakes and ponds in 2020–2021 on the TP. The concentrations of CH 4 and CO 2 under ice in winter (CH 4 , 1.05–127.16 μmol/L, CO 2 , 13.24–95.57 μmol/L) were 3–4 orders of magnitude and several times higher than those in summer (CH 4 , 0.02–2.34 μmol/L, CO 2 , 7.26–49.18 μmol/L), respectively. The CH 4 concentrations and fluxes during ice-melt increased with as the depth of the thermokarst lakes and ponds increased. However, the variation in CO 2 concentration was not significant in depth. Snowfall events played an important role in influencing gas exchange during ice-melt. In the ten lakes researched, 42.2% and 19.2% of the annual CH 4 and CO 2 fluxes occurred during ice-melt, respectively. Our results indicated that CH 4 and CO 2 accumulation in winter should be considered when evaluating annual carbon budgets in thermokarst lakes and ponds on the TP and similarly high fluxes during ice-melt might occur in other thermokarst lakes and ponds. [ABSTRACT FROM AUTHOR]

The meltwater scavenging coefficient (MSC) of black carbon (BC) is a crucial parameter in snow and sea ice models, as it determines the BC enrichment in the surface layer of melting snow over sea ice and therefore modulates the BC–snow–albedo feedbacks. We present a new method for MSC estimation by sampling the melt–refreeze ice layer that is produced from refreezing of the meltwater within snowpack and its overlying snow and measuring their physical characteristics in Elson Lagoon northeast of Utqiaġvik (formerly Barrow), Alaska, during the melting season. The bias of estimated MSC ranges from -5.4 % to 7.3 %, which is not exactly dependent on the degree of ablation. The average MSC value calculated with this proposed method is slightly lower than that derived from the repeating sampling (RS) method in Elson Lagoon while still being within its best estimate range. Further estimation demonstrates that the MSC in the Canada Basin (23.6%±2.1%) is close to that in Greenland (23.0%±12.5%) and larger than that in the Chukchi Sea (17.9%±5.0%) in the northwest of Utqiaġvik. Elson Lagoon has the lowest MSC (14.5%±2.6%) in the study areas. The method suggested in this study provides a possible approach for large-scale measurements of MSC over the sea ice area in the Arctic. Of course, this method depends on the presence of a melt–refreeze ice layer in the observation area. [ABSTRACT FROM AUTHOR]

Iron concentrations in the Southern Ocean are thought to act as a driver of the regular glacial–interglacial cycles in atmospheric carbon dioxide (CO 2). This study presents the concentrations of bioavailable Fe (dissolved Fe (DFe) and total dissolved Fe (TDFe)), major ions (Na+, K+, Mg2+, Ca2+, Cl−,NO 3 ‐,SO 4 2‐ and methanesulfonic acid (MSA)), heavy metal elements (Sr, Pb, V, Ti and Cd), and rare earth elements (REEs; specifically, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) and the oxygen and hydrogen isotopic compositions (δ18O and δD) from a series of surface snow samples collected during from January 22 to February 5, 2017 along a traverse from Zhongshan Station to Dome A in East Antarctica. The results reflect the Antarctic surface snow Fe and the other trace element concentrations on the East Antarctica ice sheet. In particular, the DFe and TDFe concentrations were measured using inductively coupled plasma sector field mass spectrometry (SF-ICP-MS). The concentration patterns of DFe and TDFe show three different stages along this transect. First, there is an abrupt decrease with distance inland from the coast and then a slight decreasing trend with increasing elevation. The maximum concentrations were observed at distances of 450–600 km from the coast, indicating that there are different potential sources and/or transporting air masses. The variations show that the sources and processes that deliver bioavailable Fe differ along this transect. These data are useful for assessing bioavailable Fe release from the Antarctic ice sheet. Unlabelled Image • The distribution of trace elements (including Fe) in East Antarctica is presented. • There are multiple sources of Fe along the transect of Zhongshan to Dome A. • The Fe peaks 450–600 km from the coast are associated with low-latitude transport. [ABSTRACT FROM AUTHOR]

Abstract The metal elements in alpine ice can provide historical information about natural mineral dust and anthropogenic pollutant emissions. To determine how the Fe concentration and flux variations relate to natural sandstorms and anthropogenic emissions from 1956 to 2004 A.D., Fe, Al, Pb and other element records were measured in a shallow ice core from the Miaoergou Glacier in East Tienshan, central Asia. The results indicate that the dissolved Fe (DFe) and total dissolved Fe (TDFe) peaks are well correlated with sandstorms from the surrounding Taklamakan Desert since at least 1956 A.D. The concentrations and fluxes of Pb show continuously increasing trends since 1995 A.D. due to the accelerating progress of the industrial revolution in China during this period, while the DFe and TDFe concentrations and the fractional Fe solubility exhibit no significant variations during this period. These results provide an ideal opportunity to investigate the effects of the natural Fe record in an arid region. Graphical abstract Image 1 Highlights • High-resolution Fe records from 1956 to 2004 were identified in the Miaoergou ice core. • The Pb element increased with anthropogenic industrial activities. • The fraction of soluble Fe varied with sandstorms from 1956 to 1990s. [ABSTRACT FROM AUTHOR]

Abstract Perchlorate concentration in a shallow ice core at Tienshan, East Asia ranged between 0.55 and 52.1 ng L−1, with significant temporal variations during 1956–2004. Since the 1980s, a clear increasing trend of perchlorate was observed in the Miaoergou ice core, possibly the result of elevated stratospheric chlorine levels caused by emissions of anthropogenic volatile chlorine compounds. Although differences in trends and amounts were observed, the 1956–2004 perchlorate data from this study compares well with the perchlorate data from the High Arctic ice cores. The spatial and temporal differences of the perchlorate in Miaoergou ice core may be due to differences in anthropogenic sources. Such as, the nitrate ore field in Turpan-Hami Basin in eastern Xinjiang, China, may be the primary anthropogenic source. From the organic chlorine species emission data, HCFC-141b, HCFC-142b and HCFC-124 were identified as the primary anthropogenic sources responsible for the two perchlorate spikes observed for 1980–1996 and 1997–2001. The Miaoergou ice core covering the 1956–2004 period provides further evidence for the perchlorate deposition variations between mid-latitudes and the High Arctic regions. Graphical abstract Unlabelled Image Highlights • The perchlorate concentrations (fluxes) were reconstructed during 1956–2004, Tienshan ice core, East Asia. • The trend of perchlorate concentrations significantly increased since 1980 with increasing anthropogenic activities. • There are multi-anthropogenic emissions result in perchlorate increasing during 1956–2004. [ABSTRACT FROM AUTHOR]

The stable oxygen isotope composition, major ions and isotopic compositions of strontium (Sr), neodymium (Nd) and lead (Pb) in insoluble dust from recent surface snow samples along the transect from the Zhongshan and Progress stations (located on the Amery Ice Shelf, East Antarctica) to Dome A (Summit, Antarctica) were analysed. No previous isotopic fingerprinting studies have been conducted for this transect. These data were used to document the dust provenances in Antarctica along the transect up to the highest site, Dome A, for the first time. The insoluble dust in snow samples along the coast displays an overall crust-line isotopic signature that is characterised by highly radiogenic 87Sr/86Sr values and less radiogenic 143Nd/144Nd values. These signatures are comparable with those of samples collected near the ice-free areas of the Zhongshan and Progress stations. Spatial differences are statistically significant along the transect, and the Sr, Nd and Pb isotope components in insoluble dust from two continuous snow samples at Dome A exhibit marked differences, indicating that additional dust reaches the East Antarctic Plateau. The isotopic characteristics of insoluble dust from this transect indicate that the long-distance natural dust and anthropogenic pollutants in these samples primarily originate from Australia. [ABSTRACT FROM AUTHOR]

The compositions of Sr and Pb isotopes in the soluble and insoluble dust in six samples from the Miaoergou ice core in eastern Tienshan, China, were measured. The six samples were dated from top to bottom as follows: 2000 AD, 1991 AD, 1983 AD, 1977 AD, 1962 AD and 1958 AD. The 87 Sr/ 86 Sr ratios in the soluble fraction ranged from 0.709984 to 0.711031. The isotopic ratios of Pb in the soluble and insoluble dust were between 17.962–18.182 and 18.198–18.409 for 206 Pb/ 207 Pb; 15.540–15.606 and 15.560–15.581 for 208 Pb/ 207 Pb; and 37.994–38.173 and 38.179–38.384 for 208 Pb/ 204 Pb, respectively. These isotopic results for insoluble dust allowed us to document the origins of the dust in the Miaoergou Glacier in eastern Tienshan. The major sources of the natural aeolian deposits were the Taklamakan and Gobi deserts. Natural and anthropogenic Pb sources were assessed using a simple ternary model in which deserts, lead ore and coal served as the primary sources of insoluble dust. Lead ore, coal combustion, and the use of leaded gasoline in the surrounding area may represent additional anthropogenic sources of soluble dust. Thus, anthropogenic sources could be further investigated by using the dust-free soluble fractions. The Pb concentration and Pb isotopic compositions from the High Asia ice cores provided distinct evidence of the positive influences of anthropogenic factors associated with industrial development and the prevailing atmospheric circulation patterns in these regions. [ABSTRACT FROM AUTHOR]

An ice core was extracted from Miaoergou Glacier, east Tien Shan, China. Concentrations of the rare earth elements (REEs) and Sr–Nd isotopic ratios were measured in insoluble dust sampled from the core. The ratios of REEs in insoluble dust were found to have characteristics typical of aeolian deposition, similar to those of sand and loess from Taklamakan. This suggests that the Taklamakan Desert might be an important source of dust reaching the Miaoergou Glacier. Sr ( 87 Sr/ 86 Sr average 0.718014 and range 0.717025 to 0.718958) and Nd (ε Nd (0) average − 9.1 and range − 9.5 to − 8.5) isotopic compositions in insoluble dust are similar to those of desert sand from Taklamakan and Gobi, suggesting that the Gobi Desert may be another major aeolian source for Miaoergou Glacier. Our results can be compared with Sr–Nd isotopic ratios from Greenland snow and ice, further demonstrating how the dust from Asian deserts contributes a high proportion of aeolian dust in the Greenland region. [ABSTRACT FROM AUTHOR]

Abstract: Recently, strong interest has been focused on immunostimulants to reducing the diseases in shrimp aquaculture. However, information regarding to the related immune-enhancing proteins in shrimps is not available yet. In this study, vitamin C (Vc), Chinese herbs (CH), and the mixture of vitamin C and Chinese herbs (Mix) were tested for their enhancement on shrimp’s immune activity. Compared with those in the control group, values of phenoloxidase (PO), superoxide dismutase (SOD) and antibacterial (Ua) activity in the Mix-treated group were improved significantly 12 or 24 days after the treatment. The cumulative mortality was also lower in the Mix-treated group after infection with Vibrio parahemolyticus. Furthermore, comparative proteomic approach was used to assess the protein expression profile in shrimps. Approximately 220–290 and 300–400 protein spots were observed in the 2-DE gels. Among them, 29 and 28 altered proteins from hemocytes and hepatopancreas, respectively, were subjected to matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF/MS) analysis. The results revealed that the main altered proteins showed high homologies with Litopenaeus vannamei hemocyanin, hemolymph clottable protein, hemoglobin beta, cytosolic MnSOD, trypsin, cathepsin I(L) and zinc proteinase Mpc1. Together, these studies found Vc and CH were suitable immunostimulants to shrimp L. vannamei, and 7 altered proteins could be involved in the enhanced immune activities. [Copyright &y& Elsevier]

In this study, a shallow ice core (12.5 m, called LGB) was drilled at the Lambert Glacial Basin, East Antarctica. The major ion and metal elements were measured at 5–6 cm resolution in this shallow core, which covered the period 1990–2017. Therefore, an annual-resolution record of iron (Fe) concentrations and fluxes were reconstructed in this shallow ice core. Although the Fe data is comparable to previous results, our results emphasized that much more dissolved Fe (DFe) from the Cerro Hudson volcanic event (August 1991) was transported to the East Antarctic ice sheet, in comparison with the Pinatubo volcanic event (June 1991). The aeolian dust may be the primary DFe source during 1990–2017. In particular, the DFe variations may be affected by the biomass burning emissions in two periods (1990–1998 and 2014–2017). While total dissolved Fe (TDFe) variations were controlled by the climatic conditions since 2000 because of the temperature (δ18O) decreasing at East Antarctica. These Fe data will be useful to assess the modern bioavailable Fe release for the Antarctica ice sheet. • High resolution DFe (TDFe) data was collected from an East Antarctic shallow core. • The eruption events can provide plenty DFe and stored in Antarctica ice sheet. • Fe variations during 1990–2017 were controlled by natural climatic characteristics. [ABSTRACT FROM AUTHOR]

To determine the potential sources of dust at high latitudes in the Northern Hemisphere, this study measured the stable isotopic ratios of strontium (Sr), neodymium (Nd) and lead (Pb) in insoluble dust in snow samples (as well as in soil and sand samples) from sites in northwestern China and high latitudes in the Northern Hemisphere: Altay (Xinjiang, China), Ny-Ålesund (Svalbard), Barrow (Alaska) and the Arctic Ocean. The combined plots of the Sr–Nd–Pb isotopic data demonstrate that there are distinctive geographic patterns among the different sampling sites. The Sr–Nd results from the Altay (Xinjiang) and Ny-Ålesund (Svalbard) sites display overall crust-like isotopic patterns, indicating that local mineral sources represent a significant contribution. The 87Sr/86Sr and ε Nd (0) data from the sea ice snow samples from the Arctic Ocean and snow samples from Barrow (Alaska) suggest potential long-range dust transport to the Arctic region. Our results indicate that Russia may be a source of anthropogenic pollutants for the high Arctic region, while North America may be a source of anthropogenic pollutants for Barrow, Alaska. These findings are beneficial for protecting the environment at the global scale. Image 1 • New Sr–Nd–Pb data from Arctic and western Chinese snow samples are presented. • East Asian deserts are the primary dust source for the Arctic regions. • The anthropogenic pollutants in Arctic regions may be from Russia and North America. [ABSTRACT FROM AUTHOR]

Simple Summary: The intestine is an important immune organ of the body in which the gut microbiota plays an important function. Gut microbiota is considered an important "organ" and is receiving increasing attention. This study investigated the diversity of gut microbiota in different intestinal segments of blue foxes, and the similarity between fecal microbiota and gut microbiota in samples taken before and after weaning. The types, distribution characteristics, and patterns of microorganisms in different intestinal segments of blue foxes differed before and after weaning. Except for the rectum, the dominant microbiota of each intestinal segment before and after weaning changed significantly. The fecal microbiota structure of weaned blue foxes cannot represent the exact structural characteristics of the entire gut microbiota but can represent the structural characteristics of the colon and rectum gut microbiota. Intestinal flora plays an important role in maintaining the internal stability and health of the intestine. Currently, intestinal microbes are considered an important "organ" but are mostly ignored by people. This study evaluated the flora structure of each intestinal segment of blue foxes pre-weaning and explored the differences between the fecal flora and intestinal flora structure of each segment after weaning. Samples of intestinal contents from three blue foxes at 45 days of age (before weaning) and intestinal contents and feces samples from at 80 days (after weaning) were collected for 16s rRNA flora analysis. The species and distribution characteristics of microorganisms in different intestinal segments of blue foxes before and after weaning were different. Except for the rectum, the dominant flora of each intestinal segment of blue fox changed significantly after experiencing weaning, and the fecal flora structure of young fox at the weaning stage did not represent the whole intestinal flora structure but was highly similar to that of the colon and rectum. To sum up, the intestinal flora of blue foxes changed systematically before and after weaning. When performing non-invasive experiments, the microflora structure of the colon and rectum of blue foxes can be predicted by collecting fecal samples. [ABSTRACT FROM AUTHOR]

Arctic sea ice loss and the associated enhanced warming has been related to midlatitude weather and climate changes through modulate meridional temperature gradients linked to circulation. However, contrasting lines of evidence result in low confidence in the influence of Arctic warming on midlatitude climate. This study examines the additional perspectives that palaeoclimate evidence provides on the decadal relationship between autumn sea ice extent (SIE) in the Barents-Kara (B-K) Seas and extreme cold wave events (ECWEs) in southern China. Reconstruction of the winter Cold Index and SIE in the B-K Seas from 1289 to 2017 shows that a significant anti-phase relationship occurred during most periods of decreasing SIE, indicating that cold winters are more likely in low SIE years due to the "bridge" role of the North Atlantic Oscillation and Siberian High. It is confirmed that the recent increase in ECWEs in southern China is closely related to the sea ice decline in the B-K Seas. However, our results show that the linkage is unstable, especially in high SIE periods, and it is probably modulated by atmospheric internal variability. [ABSTRACT FROM AUTHOR]

Abstract Based on the field measurements in Barrow, Alaska within the period of April–May 2015, we investigate the sources and variations of elemental carbon (EC) and organic carbon (OC) in the surface layer of snowpack on sea ice, and estimate their effects on the sea ice albedo. Results show that the snow OC in Barrow are from natural sources (e.g. terrestrial higher plants and micro-organisms) mainly, as well as biomass burning (e.g. forest fires and straw combustion) as an important part. Both EC and OC can accumulate at the snow surface with snow melt. The variations in EC and OC and liquid water content in the snow layer are well consistent during the snow-melting period. A higher rate of snow melt implied a more efficient enrichment of EC and OC. In the last phase of snow melt, the concentration increased to a maximum of 16.2 ng/g for EC and 128 ng/g for OC, which is ∼10 times larger than those before snow melt onset. Except for the dominant influence of melt amplification mechanism, the variation in concentrations of EC and OC could be disturbed by the air temperature fluctuation and snowfall. Our study indicates that the light-absorbing impurities contributed 1.6%–5.1% to the reduction in sea ice albedo with melt during the measurement period. The significant period of light-absorbing impurities influencing on sea ice albedo begins with the rapid melting of overlying snow and ends before the melt ponds formed widely, which lasted for about 10 days in Barrow, 2015. [ABSTRACT FROM AUTHOR]

Considering the difficulty of power supply for automatic observation equipment in the polar regions, this paper introduced a small standalone renewable energy system with wind–solar co-generation as the energy supply scheme. Mathematical models were given, including solar photovoltaic panels, wind turbines, solar irradiance, wind energy density, and renewable energy assessment. ERA-Interim atmospheric reanalysis data were used to evaluate solar energy resources, and the synergistic effect of wind–solar resources on renewable energy was also analyzed and discussed. The system composition of the small standalone renewable energy system was proposed in this study. This system deployed near Zhongshan Station was taken as the object of investigation to analyze the operation performance of each component of the system in different months, and the technical feasibility of the system has also been verified. The results showed that the wind–solar resources in the polar regions had a synergistic effect, which can provide an effective and feasible scheme for the power supply of automatic observation equipment. Through research and analysis, it was found that each component of the renewable energy system, including photovoltaic panels, wind turbines, and batteries, could meet the long-term power supply requirements of automatic observation regardless of the polar periods, polar day or polar night. This paper can not only provide theoretical and data support for the application of small independent renewable energy systems in the polar regions but also provide feasible solutions for clean energy supply of the systems and equipment for independent observation stations deployed in uninhabited islands and alpine regions. [ABSTRACT FROM AUTHOR]

Simple Summary: Aquaculture in Northeast China has favored Rana dybowskii (R. dybowskii) because of its regional specificity and the economic value of the female frog's ovary, and the increasing proportion of female frogs is beneficial to improve the economic efficiency of aquaculture. Unfortunately, the sexual reversal from genotypic female to phenotypic male has led to a decrease in the proportion of females in the breeding population. In this study, differentially expressed genes between testes of sex reversal and male testes were screened by transcriptome sequencing. These findings provide a comprehensive analysis of gene expression in R. dybowskii sex reversal from genotypic female to phenotypic male and provide new ideas for sex control of R. dybowskii. Rana dybowskii (R. dybowskii) is an ecological species found in China, Japan, Korea, and Russia. Like most amphibians, R. dybowskii lacks heterotypic sex chromosomes, limiting the in-depth study of sex determination and sex reversal mechanisms. Previous studies have shown that certain environmental factors can modify R. dybowskii genotypic females into phenotypic males, but the mechanism is still unknown. Considering the difficulties in identifying and collecting sex reversal gonads at different stages of differentiation under natural conditions, testes from sexually mature wild adult R. dybowskii were taken in this study, and the genotypic sex of individuals and sex reversal were identified by two male-linked genetic markers reported in our most recent findings. Transcriptome sequencing was performed on testicular tissue from males and pseudo-males, as well as female ovary tissue. The results show that the gene expression patterns of pseudo-males' testes were similar to those of the males but highly differed from females' ovaries. One hundred and seventeen differentially expressed genes between testes of pseudo-males and males were found, and the up-regulation of doublesex and mab-3 related transcription factor 1 (Dmrt1) in testes of pseudo-males may play a key role in R. dybowskii sex reversal. [ABSTRACT FROM AUTHOR]

• Microstructure and mechanical properties of SLM-ed and LMD-ed TA15 were compared systematically. • From a point of practical industrial applications, productivity and forming cost of fabricated TA15 samples were evaluated. • A reference for selecting optimized fabrication methods for practical industrial applications was provided considering comprehensive properties. In the present study, Ti-6.5Al-2Zr-1Mo-1V (TA15) alloy, one of the widely used near-α titanium alloys in the field of aeronautical and astronautical, was fabricated by two lasers additive manufacturing technologies, namely selective laser melting (SLM) and laser metal deposition (LMD). Microstructure, mechanical property, productivity, and forming cost of fabricated TA15 samples by these two processes were compared systematically. The results showed that the microstructure of the SLM-ed and LMD-ed samples exhibited differences in terms of crystallographic orientations, grain boundaries, and grain sizes, which was mainly attributed to the distinct thermal histories associated with each process. Such differences resulted in the LMD-ed sample presenting anisotropy, lower tensile strength, and higher elongation compared to the SLM-ed sample. Cost analysis indicated that the forming cost per unit volume of the LMD-ed sample was about half that of the SLM-ed sample. This difference was primally due to the higher productivity of the LMD process (226.1 cm3/h) compared to the SLM process (8.8 cm3/h), as well as the lower power cost of the powder materials (60 vs. 100 $/kg). Furthermore, the forming maximum volume of the LMD process (∼30.38 m3) was about 28 times than that of the SLM process (∼1.08 m3). In conclusion, this study provides a detailed comparison between SLM-ed and LMD-ed TA15 samples. The findings can act as a reference for selecting optimized fabrication methods for practical industrial applications, taking into consideration specific mechanical properties, forming size, and cost requirements. [ABSTRACT FROM AUTHOR]

Stable isotope ratios (δ18O and δD) in Antarctic snow and ice are basic proxy indices of climate in ice core studies. The relation between the ratios has important indicative significance for moisture sources. In general, the fractionation characteristics of the two isotopes vary with different meteorological and topographical conditions. This paper presents the spatial and temporal distribution of meteoric water line (MWL) slopes along a traverse from the Zhongshan Station (ZSS) to Dome A in East Antarctica. It is found that the slopes decrease with the increasing distance inland from the coast and the lowest slope occurred at Dome A, where the long-range transported moisture dominates and clear sky snowing have an influence. The slopes in different layers of the snowpack showed a decreasing trend with depth and this is attributed to the fractionation during the interstitial sublimation and re-condensation processes of the water vapor. Frost flower development on the interior plateau surface can greatly alter the depth evolution of the MWL slope. The coastal snow pits also go through the post-depositional smoothing effect, but their influences are not so significant as the inland regions. [ABSTRACT FROM AUTHOR]

Refractory black carbon (rBC) aerosols emitted by biomass burning and fossil fuel combustion can cause significant climatic forcing when it deposited on the snow. The Southern Hemisphere (SH) biomass burning emissions represent a significant part of rBC in and around Antarctica. Here we present the spatial and temporal variations of rBC from the surface snow and snow pits samples along the coastal Zhongshan Station (ZSS) to inland Dome A transect in Lambert Glacier region of eastern Antarctica. The geometric mean concentrations of surface snow rBC was 0.017 ± 0.018 ng g−1 and showed higher values in the inland plateau region (900–1248 km, 0.031 ± 0.024 ng g−1) than the coastal region (0–400 km, 0.011 ± 0.005 ng g−1) and there exist similar spatial results for the inland snowpit (0.021 ± 0.017 ng g−1) and coastal snowpit (0.018 ± 0.013 ng g−1). The records from the coastal snowpit (SP-A) show that the rBC from 2009 to 2016 displays weak seasonal variations, while in the inland snowpit (SP–C) the records spans from 1950 to 2015 and showed the rBC concentrations vary and relate with the open biomass burning emission in the Southern Hemisphere. • Spatial and temporal variations of the rBC along the transect from ZSS to Dome A in eastern Antarctica were retrieved. • Higher geometric mean rBC concentrations in the interior section than the coastal section were detected. • Dome A rBC record during 1950 and 2015 shows good relation with the open biomass burning in the Southern Hemisphere. [ABSTRACT FROM AUTHOR]

Snow plays an important role in the Arctic climate system, modulating heat transfer in terrestrial and marine environments and controlling feedbacks. Changes in snow depth over Arctic sea ice, particularly in spring, have a strong impact on the surface energy budget, influencing ocean heat loss, ice growth and surface ponding. Snow conditions are sensitive to the phase (solid or liquid) of deposited precipitation. However, variability and potential trends of rain-on-snow events over Arctic sea ice and their role in sea-ice losses are poorly understood. Time series of surface observations at Utqiaġvik, Alaska, reveal rapid reduction in snow depth linked to late-spring rain-on-snow events. Liquid precipitation is key in preconditioning and triggering snow ablation through reduction in surface albedo as well as latent heat release determined by rainfall amount, supported by field observations beginning in 2000 and model results. Rainfall was found to accelerate warming and ripening of the snowpack, with even small amounts (such as 0.3 mm recorded on 24 May 2017) triggering the transition from the warming phase into the ripening phase. Subsequently, direct heat input drives snowmelt, with water content of the snowpack increasing until meltwater output occurs, with an associated rapid decrease in snow depth. Rainfall during the ripening phase can further raise water content in the snow layer, prompting onset of the meltwater output phase in the snowpack. First spring rainfall in Utqiaġvik has been observed to shift to earlier dates since the 1970s, in particular after the mid-1990s. Early melt season rainfall and its fraction of total annual precipitation also exhibit an increasing trend. These changes of precipitation over sea ice may have profound impacts on ice melt through feedbacks involving earlier onset of surface melt. [ABSTRACT FROM AUTHOR]

Abstract To reveal PM 1 vertical profiles and key affecting factors in a typical urban valley, daytime and nighttime PM 1 (the particles with diameters less than 1 μm) samples were collected with medium volume air samplers during 26 December 2017 to 11 January 2018 at five different altitudes by means of high topographic relief at urban areas of Lanzhou. The synchronous boundary layer temperature and humidity profiles were observed by a microwave radiometer. Daytime PM 1 concentrations reduced by about 3.86 μg m−3 when the height above the surface increased by 100 m, which was much lower than that for nighttime (5.68 μg m−3 100 m−1) as particles were easily accumulated near the surface when the air was stable during the nighttime. The three typical PM 1 vertical profiles were identified by K-means clustering technique. The most frequent cluster with elevated PM 1 concentrations near the surface was closely related to temperature inversion around the ground, while the cluster with relatively uniform PM 1 within the boundary layer was mainly induced by unstable atmospheric stratification and thus relatively good vertical dispersion. About 50%–60% of PM 1 variations could be attributed to atmospheric stratification near the surface in the valley city, which was much higher than that at the hilltop. The PM 1 difference increased by 47.14 (36.91) μg m−3 when inversion layer thickness (intensity) increased by 100 m (1 °C 100 m−1). The newly calculated inversion index considering both inversion layer thickness and intensity explained about 87% of PM 1 differences between near the surface and at the hilltop. The vertical dispersion had a more significant effect on PM 1 than horizontal dispersion near the surface, while PM 1 was more largely affected by horizontal dispersion at the hilltop, which was closely related to the valley terrain. Highlights • PM 1 vertical profiles were revealed in urban areas of Lanzhou for the first time. • Three typical PM 1 profile types were identified using K-means clustering technique. • PM 1 concentrations reduced by about 3–5 μg m−3 when the height increased by 100 m. • 50%–60% of PM 1 variations were attributed to atmospheric stratification near the surface. • PM 1 was more largely affected by vertical dispersion near the surface. [ABSTRACT FROM AUTHOR]

Wind-blown dust derived from the arid and semi-arid regions is an important atmospheric component affecting the Earth's radiation budget. Dust storms are prevailing in central Asia. Deposition of atmospheric dust in snow was measured on Glacier No.12 (5040 m a.s.l.) in the Laohugou Basin and Shiyi Glacier (4510 m a.s.l.) in the Yeniugou Basin, of western Qilian Mountains, China, mainly focusing on dust concentration and size distribution, chemistry, SEM-EDX analysis and Nd-Sr isotopic composition. An analysis of spatial distribution of dust concentration and size distribution in the snow cover at two sites suggests that deposition of dust in western Qilian Mountains is different between sites as the environment changes from west to east. Mean mass concentration of dust with 0.57 < d<40 µm in the snow is 3461 µg kg-1 on Glacier No.12 and 2876 µg kg-1 on Shiyi Glacier, respectively. Annual flux of dust deposition to western Qilian Mountains has a range of 143.8-207.6 µg cm-2 yr-1 for particles with 0.57 < d<40 µm. Dust layers in the snowpit contain Ca- and Na-rich materials typically found in Asian dust particles. Number-size distribution indicated that most of the dust diameter is <2.0 µm, implying the significant influences of finer particles to alpine glacier regions of central Asia. Volume size distributions of dust particles showed single-modal structures having volume median diameters from 3 to 22 µm, which is comparable to the results of dust deposition on glaciers of the adjacent Tianshan Mountains in western China. SEM-EDX analysis suggested that dust particles were mainly composed of mineral particles, besides some fly ash particles and soot. EDX shows that mineral particles contain Si-, Al-, Ca-, K-, and Fe-rich materials, such as quartz, albite, aluminate, etc. The Nd-Sr isotopic composition of insoluble particles in two glaciers showed that Badain Jaran Desert and Qaidam Basin were the most possible source regions of dust in the western Qilian Mountains. Physicochemical constituents of dust indicated that the snowpack was influenced by both local atmospheric environment, e.g. local dust, and anthropogenic activities in central Asia. [ABSTRACT FROM AUTHOR]

For the first time we investigate the basal thermal condition in the upper area of Jima Yangzong Glacier, the headstream of Yarlung Zangbo River, using ground-penetrating radar techniques. With common offset and common mid-point surveys we analyze the radar velocities in ice with respect to cold-temperate ice transition surface (0.1751 ± 0.0028 m ns) and ice-bedrock interface (0.1657 ± 0.0033 m ns), indicating a radar velocity of 0.1410 ± 0.0154 m ns for the temperate ice layer (16.6 ± 1.8 m). We estimate that the temperate ice layer has a water content of around 6 % ± 4 %, suggesting that the Jima Yangzong Glacier, previously known as continental-type, now possibly becomes polythermal. [ABSTRACT FROM AUTHOR]

Abstract: Hemocyanin is an extracellular copper-containing protein present in the hemolymph of both mollusks and arthropods. The traditionally recognized function of hemocyanin is for oxygen transport. Lately, it was demonstrated that hemocyanin is a multifunctional protein, especially participating in multiple roles of immune defense. For better understanding its actions in immune defense, the hemolytic activity of hemocyanin from shrimp Litopenaeus vannamei and the mechanism were investigated in this study. The results showed that shrimp hemocyanin exhibited hemolytic activity against vertebrate erythrocytes. The hemolysis displayed dependencies on hemocyanin concentration, pH, temperature and divalent cations. The highest activity occurred at a concentration of 0.125 mg ml−1, and pH 6.0, 40 °C in the presence of calcium. Moreover, from the incubation products of erythrocytes with hemocyanin, besides two subunits of hemocyanin, two molecules around 150 and 230 kD were isolated and speculated as oligomers of hemocyanin. Further evidence revealed that the hemolysis could be inhibited to different degrees by osmoprotectants with high molecular masses, suggesting that it follows a colloid-osmotic mechanism. These results indicate that L. vannamei hemocyanin has a novel function with hemolytic activity, partly related to a colloid-osmotic mechanism mediated by its oligomers. [Copyright &y& Elsevier]