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In this paper, we report on abundant fossils of Platybelodon from the Middle Miocene of the Linxia Basin, China. Most of the fossils were discovered at two localities (Laogou and Zengjia) in the upper Middle Miocene Hujialiang Formation, and possess derived characters for the genus, including a relatively slender upper incisor, the development of a transverse ledge on the narrowest part of the mandibular symphysis, narrow, elongate and hypsodont third molars, the development of fourth loph(id)s on the second molars, and the development of small enamel conules and cementum in the interloph(id)s. Following comparisons with other Eurasian platybelodonts, we assign these remains to Platybelodon grangeri, and demonstrate that they are morphologically intermediate between P. grangeri from the Tunggurian localities of Tarim Nor and Platybelodon Quarry in Inner Mongolia. We suggest that the locality of Laogou may be younger than that of Zengjia, based on the occurrence of platybelodonts showing a suite of more derived characters. In addition, we assign two further specimens of Platybelodon from the lower Middle Miocene Dongxiang Formation of the Linxia Basin to Platybelodon danovi, owing to their retention of plesiomorphic characters distinguishing them from other Linxia Platybelodon fossils. Based on a cladistic analysis, we propose an evolutionary sequence of platybelodonts in Eurasia, and discuss potential functional adaptations.
Freeze-thaw (FT) cycles occur annually in soils of mesic and frigid temperature regimes. FT has profound impacts on soil aggregates yet is often difficult to document in field settings. As a result, laboratory-based FT experiments are widely used, albeit with their own limitations. Both laboratory and field-based research indicates that aggregate properties vary with rates of freezing and thawing as well as the number and amplitudes of FT cycles. In this study, we introduce a continuous freezing-to-thawing-to-freezing technique (i.e., “VTR”) and compare it to a commonly used discrete freeze-then-thaw-then-freeze method (i.e., “RTCR”) and compare both results to natural seasonal changes. Our study soil is the A horizon of the major cropped mollisol in northeastern China. We examined it under natural field soil moisture conditions as well as two controlled soil moisture contents in the laboratory. Both RTCR and VTR show a decrease in large (>1mm) aggregate content and a corresponding increase in medium (0.5 to 0.2 mm) aggregates (P>0.05) that is proportional to the number of FT cycles and soil moisture content. Wet aggregate stability (WAS) increased (P<0.05) over the time of the experiment with each method. RTCR data showed an interaction between FT cycles and soil water content. VTR was better, although certainly not with better matched field results than RTCR, which we attribute its FT cycles being matched to anactual field. These results confirm the dependability and authenticity of the VTR technique.
The dynamic strength and accumulated plastic strain are two important parameters for evaluating the dynamic response of soil. As a special clay, the remolded red clay is often used as the high speed railway subgrade filling, but studies on its dynamic characteristics are few. For a thorough analysis of the suitability of the remolded red clay as the subgrade filling, a series of long-term cyclic load triaxial test under different load histories are carried out. Considering the influence of compactness, confining pressure, consolidation ratio, vibration frequency and dynamic load to the remolded red clay dynamic property, the tests obtain the development curves of the dynamic strength and accumulated plastic strain under different test conditions. Then, through curve fitting method, two different hyperbolic models respectively for the dynamic strength and accumulated plastic strain are built, which can match the test datum well. By applying the dynamic strength model, the critical dynamic strength of the remolded red clay are gained. Meanwhile, for providing basic datum and reference for relevant projects, all key parameters for the dynamic strength and accumulated plastic strain of the remolded red clay are given in the paper
Agriculture has the dual attributes of being a carbon source and a carbon sink. The agricultural carbon compensation mechanism is important for increasing agricultural carbon sink and reducing agricultural carbon emissions. However, there is no specific entry threshold for the implementation of agricultural carbon compensation in China. Taking the two indicators of agricultural carbon sink level and agricultural carbon emission intensity as the basic indicators, and taking the regional average agricultural carbon sink level and the regional average agricultural carbon emission intensity as the baseline, we established the agricultural carbon compensation area selection process. According to the agricultural carbon compensation area selection process, the results obtained in Hotan Prefecture were reasonable. The result of selection accorded with the actual situation of agricultural carbon emission and agricultural carbon sinks in Hotan Prefecture.
Background. Traditional Chinese herbs (TCHs) are widely used for improving non-specific immunity of fish in aquaculture. Possible effects of many important TCH on red drum, Sciaenops ocellatus (Linnaeus, 1766), have not been adequately studied. The aim of the presently reported study was to investigate the effects of ten TCH on selected immunological- and haematological responses of red drum. Materials and Methods. >Ten TCH preparations, consisting of selected parts of plants and fungi, known in medicinal practice as: Astragalus membranaceus, fructus forsythiae, Polyporus umbellatus, Scutellaria baicalensis, Wolfiporia extensa, rhizoma coptidis, radix glycyrrhizae, flos lonicerae japonicae, isatidis radix, and bupleuri radix were used in the experiment. A dose of 10 g of each TCH was decocted and concentrated, then mixed with the diets (mixed diets) at ratio of 2%. After 28 days of feeding, the fish were infected with Vibrio splendidus and observed for 14 days for possible mortalities. Leukocyte phagocytic activity and lysozyme activity (LZM) were measured on days 0, 3, 7, 14, 21, 28, and 35. Relative percentage survival (RPS) of each TCH treatment was also investigated after the fish exposure to V. splendidus. Results. Red drum fed 2% doses of individual TCH extracts significantly (P < 0.05) increased its: phagocytic percentage (PP) (with the exception of flos lonicerae japonicae treatment), phagocytic index (PI) (with the exception of flos lonicerae japonicae- and bupleuri radix treatments), LZM (with the exception of Wolfiporia extensa treatment), and RPS (with the exception of P. umbellatus, Wolfiporia extensa-, radix glycyrrhizae-, flos lonicerae japonicae-, isatidis radix-, and bupleuri radix treatments). The indexes of PP, PI, and LZM, for all experimental groups, decreased quickly on day 35 (7 days after TCH diets were discontinued). On the other hand, PP values were significantly (P < 0.05) higher than in control (with the exception of flos lonicerae japonicae- and Wolfiporia extensa treatments). Also PI values were significantly higher (P < 0.05) than in control (with the exception of flos lonicerae japonicae-, Wolfiporia extensa-, and bupleuri radix treatments). LZM values exhibited no significant difference (P > 0.05) in all treatment groups compared with control. Most importantly, the A. membranaceus-, or S. baicalensis-, or fructus forsythiae-fed groups were significantly protected (P < 0.01) against V. splendidus challenge compared to control. RPS of A. membranaceus- and S. baicalensis groups were the highest, reaching 88.9% on day 28, followed by the fructus forsythiae group, whereas bupleuri radix- and Wolfiporia extensa treatments showed the lowest values. Conclusion. A. membranaceus, S. baicalensis, and fructus forsythiae were effective in preventing red drum from acquiring the disease while challenged by V. splendidus.
Relatively successful elsewhere, gene delivery aimed at the vasculature and kidney has made very little progress. In the kidney, the hurdles are related to the unique structure-function relationships of this organ and in the blood vessels to a variety of, mostly endothelial, factors making the delivery of transgenes very difficult. Among gene-therapeutic approaches, most viral gene delivery systems utilized to date have shown significant practical and safety-related limitations due to the level and duration of recombinant transgene expression as well as their induction of a significant host immune response to vector proteins. Recombinant adeno-associated virus (rAAV) vectors appear to offer a vehicle for safe, long-term transgene expression. rAAV-based vectors are characterized by a relative non-immunogenicity and the absence of viral coding sequences. Furthermore, they allow for establishment of long-term latency without deleterious effects on the host cell. This brief review addresses problems related to transgene-delivery to kidney and vasculature with particular attention given to rAAV vectors. The potential for gene therapy as a strategy for selected renal and vascular diseases is also discussed.
Urbanization changes the abundance and type of resources upon which birds depend, including the type and availability of nesting materials. Although more and more bird species worldwide are colonizing and adapting to urban environments, the ecological processes underlying the responses to urbanization and the relevant resource changes remain unclear. Here we examined the responses of the Chinese Bulbul Pycnonotus sinensis to urbanization by assessing nest composition and available nesting materials at five land-use categories (mountains, farmlands, riparians, urban parks, strips of street trees) of intensifying development in Hangzhou, China. In each land-use category, we classified used and available nesting materials as anthropogenic (e.g. plastics, paper pieces, cloth pieces, nylon particles, threads) or natural materials (e.g. plant culms, roots, leaves). We found that the proportion of anthropogenic nesting materials used by Chinese Bulbuls differed significantly across land-use categories, and it increased significantly with urbanization. Additionally, the increasing amount of anthropogenic nesting materials with urbanization can be attributed to an increase in the availability of anthropogenic nesting materials toward the urban core. Our results indicate that Chinese Bulbuls can adjust the composition of their nests in response to urbanization.
The flooding process is one of the main concerns of damaged ship stability. This paper combines the volume of fluid (VOF) method incorporated in the Navier-Stokes (NS) solver with dynamic mesh techniques to simulate the flooding of a damaged ship. The VOF method is used to capture the fluid interface, while the dynamic mesh techniques are applied to update the mesh as a result of transient ship motions. The time-domain flooding processes of a damaged barge and a rectangular cabin model are carried out based on the abovementioned method, and the computational results appear compatible with the experimental data. During the flooding process, the motion of the flooding flow at different stages is observed and compared with that observed in real conditions. The time-domain research of the flooding process is the starting point for subsequent establishment of damaged ship’s roll movement and capsizing the mechanism of dead ship condition in wave
Biochar’s production and application in soils has been suggested as a means of abating climate change by sequestering carbon while simultaneously providing energy and increasing crop yields. However, little is known about biochar’s effect on nitrification in alkaline soil. This study focused on the effect of wheat straw-derived biochar (0%, 2%, 5%, and 10%, w/w) on nitrification in a calcareous clay soil with an incubation experiment. Moreover, the variations of ammonia-oxidizing bacteria (AOB) amount, urease activity, pH, and inorganic nitrogen contents during the incubation and their relationships with potential nitrification rates were also explored. The results indicated that nitrification was enhanced by wheat straw-derived biochar and showed an obvious dose-response to biochar application rate. Generally, the potential nitrification rate increased with incubation time elapsing for all four treatments, which were in the ranges of 21.0-33.9, 23.7-45.1, 21.4-57.5, and 31.8-66.1 nmol N/(g dry soil∙h), respectively. The potential nitrification rate increased by 1.36-2.40 times at 10% biochar application rate compared with the control (0%) at the same incubation stage. Except for NH₄⁺-N content of the soil-biochar mixture, AOB amount, urease activity, pH, and NO₃⁻-N content all showed increasing trends during incubation. Moreover, correlation analysis indicated that the potential nitrification rate was positively correlated with AOB amount, urease activity, pH, and NO₃⁻-N content (r≥0.713, P<0.01), but negatively correlated with NH₄⁺-N content (r = -0.408, P<0.01). Notably, though the biochar application in the Loess Plateau region has more benefits for soil condition improvement, the enhanced nitrification induced by biochar may pose a negative effect on fertilizer bioavailable efficiency in the agricultural system.
The aims of current study are to asses the levels of heavy metals (Cr, Cu, Ni, Fe, Zn, Co, Pb, and Cd) in sediments of lakes in Yangtze wetland and discuss the relationships between the sources and human activities. A total of 54 samples covering seven lakes along the Yangtze route in Anqing were selected. The concentrations of metals in lake sediments were (mg-kg⁻¹): Cr, 4.08~12.58; Cu, 22.40~74.36; Ni, 29.89~142.17; Fe, 22899.20~50956.40; Zn, 102.31~242.04; Co, 8.35~26.89; Pb, 23.38~88.77; and Cd, 0.29~2.95. The situation of Xizi Lake was the most serious among the seven lakes investigated. Geoaccumulation index (Igeo) analysis showed that overall risk of heavy metals in sediments was approximately in the order: Cd > Pb = Zn = Cu = Ni > Fe > Co = Cr. The results of principal component analysis (PCA) suggested the main sources of Cd, Cu, Zn, Ni, and Pb on PC 1 were fuel combustion, metal smelting, industrial manufacturing, and other human activities, while Fe on PC 2 originated fromrock weathering and other geochemical processes.
With the development of the economy and industrial construction, air quality deteriorates dramatically in China and seriously threatens people’s health. To investigate which factors most affect air quality and provide a useful tool to assist the prediction and early warning of air pollution in urban areas, we applied a sensor that observed air quality big data, information theory-based predictor significance identification, and PEK-based machine learning to air quality index (AQI) analysis and prediction in this paper. We found that the stability of air quality has a high relationship with absolute air quality, and that improvement of air quality can also improve stability. Air quality in southern and western cities is better than that of northern and eastern cities. AQI time series of cities with closer geophysical locations have a closer relationship with others. PM2.5, PM10, and SO2 are the most important impact factors. The machine learning-based prediction is useful for AQI prediction and early warning. This tool could be applied to other city’s air quality monitoring and early warning to further verify its effectiveness and robustness. Finally, we suggested the use of a training data sample with better quality and representatives to further improve AQI prediction model performance in future research.
Sexual dimorphism is reviewed and described in adult skulls of Chilotherium wimani from the Linxia Basin. Via the analysis and comparison, several very significant sexually dimorphic features are recognized. Tusks (i2), symphysis and occipital surface are larger in males. Sexual dimorphism in the mandible is significant. The anterior mandibular morphology is more sexually dimorphic than the posterior part. The most clearly dimorphic character is i2 length, and this is consistent with intrasexual competition where males invest large amounts of energy jousting with each other. The molar length, the height and the area of the occipital surface are correlated with body mass, and body mass sexual dimorphism is compared. Society behavior and paleoecology of C. wimani are different from most extinct or extant rhinos. M/F ratio indicates that the mortality of young males is higher than females. According to the suite of dimorphic features of the skull of C. wimani, the tentative sex discriminant functions are set up in order to identify the gender of the skulls.
UV-C irradiation treatment has been demonstrated to be able to enhance chilling tolerance in peach (Prunus persica L. Batsch) during postharvest cold storage. Sugar and organic acid play central roles in plant metabolism. However, little is known about the relationships among chilling injury, soluble sugar and organic acid in peaches subjected to UV-C. In this study, peaches were irradiated with UV-C (1.5 kJ/m²) and then stored at 1 °C for 35 days. The content of sugar and organic acid, activities of enzymes, and the expression of enzyme genes that catalyze the metabolism of sugar and acid were evaluated. Results showed that UV-C significantly alleviated chilling injury and maintained the quality of peaches during storage. For sugar metabolism, UV-C suppressed sucrose degradation and glucose production mostly by inhibiting the enzyme activity and mRNA transcription of invertase (β-D-fructofuranoside fructohydrolase; EC 3.2.1.26) during the cold storage. For organic acid metabolism, UV-C irradiation downregulated the enzyme activities and gene expressions of aconitase (citrate hydrolyase; EC 4.2.1.3), and NADP-malic enzyme (S-malate: NADP-oxidoreductase; EC 1.1.1.40), but upregulated the enzyme activities and gene expressions of citrate synthase (acetyl-CoA: oxaloacetate C-acetyltransferase; EC 2.3.3.1) and NAD-malate dehydrogenase (L-malate: NAD-oxidoreductase; EC 1.1.1.37), leading to the low degradation of citric and malic acids during the whole storage periods. These results suggest that UV-C enhanced chilling tolerance in peach fruit during cold storage by suppressing the degradations of sucrose, citric, and malic acids.
Background. Lactobacillus bulgaricus LB6 is a bacterium which was selected in the commercial yoghurt with high angiotensin converting enzyme (ACE) inhibitory activity. Preparation of concentrated starter cultures via freeze drying is of practical importance to dairy and food industries. Material and methods. We optimized the optimal sugar alcohol and proteins for Lactobacillus bulgaricus LB6 during the process of freeze drying using a Plackett-Burman design. In our initial tests survival rate and the number of viable cells were associated with the type of ly oprotectant used and so our optimization protocol focused on increasing survival rate. Substances that had previously had a protective effect during freeze drying were investigated, for example: mannitol, sorbitol, xylitol, meso-erythritol, lactitol, whey protein isolate 90, bovine serum albumin, and whey protein concentrate 80 and soy protein isolate 70. Results. We found that the optimum sugar alcohol and proteins for survival of Lactobacillus bulgaricus LB6 were whey protein concentrate (p = 0.0040 for survival rate), xylitol (p = 0.0067 for survival rate) and sorbitol (p = 0.0073 for survival rate), they showed positive effect (whey protein concentrate and sorbitol) or negative effect (xylitol). Discussion. The effectiveness of three chosen sugar alcohols and protein implied that they could be used as lyoprotectant for Lactobacillus bulgaricus LB6 in the further research, the optimal composition of sugar alcohol and protein for the lyoprotectant use must be established.
Mung bean CYP90A2 is a putative brassinosteroid (BR) synthetic gene that shares 77% identity with the Arabidopsis CPD gene. It was strongly suppressed by chilling stress. This implies that exogenous treatment with BR could allow the plant to recover from the inhibited growth caused by chilling. In this study, we used proteomics to investigate whether the mung bean epicotyl can be regulated by brassinosteroids under conditions of chilling stress. Mung bean epicotyls whose growth was initially suppressed by chilling partly recovered their ability to elongate after treatment with 24-epibrassinolde; 17 proteins down-regulated by this chilling were re-up-regulated. These up-regulated proteins are involved in methionine assimilation, ATP synthesis, cell wall construction and the stress response. This is consistent with the re-up-regulation of methionine synthase and S-adenosyl-L-methionine synthetase, since chilling-inhibited mung bean epicotyl elongation could be partially recovered by exogenous treatment with DL-methionine. This is the first proteome established for the mung bean species. The regulatory relationship between brassinosteroids and chilling conditions was investigated, and possible mechanisms are discussed herein.
Sucrose is the principal form of photosynthesis products, and long-distance transport of sucrose requires sucrose transporters (SUTs) to perform loading and unloading functions. SUTs play an important role in plant growth, development and reproduction. In this study, five unique sucrose transporter (SbSUT) genes that contain full-length cDNA sequences were cloned from sweet sorghum, and these SbSUT genes were clustered into four different clades: SUT1, SUT3, SUT4 and SUT5. Heterologous expression of SbSUTs in yeast demonstrated that they were functional sucrose transporters. Tissue-specific expression profiles showed that sorghum SUT genes had different tissue-specific expression patterns, suggesting that sorghum SUT genes may play an important role in plant growth and developmental processes. After defoliation, expression patterns of SbSUT1, SbSUT2 and SbSUT4 were different in leaf sheaths, leaves and roots. Taken together, the results indicate that the above mentioned five unique sucrose transporter genes may play important roles in performing sucrose loading and unloading functions and that they exhibit different expression in response to leaf blade removal.
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