23 research outputs found

    LAD-RCNN:A Powerful Tool for Livestock Face Detection and Normalization

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    With the demand for standardized large-scale livestock farming and the development of artificial intelligence technology, a lot of research in area of animal face recognition were carried on pigs, cattle, sheep and other livestock. Face recognition consists of three sub-task: face detection, face normalizing and face identification. Most of animal face recognition study focuses on face detection and face identification. Animals are often uncooperative when taking photos, so the collected animal face images are often in arbitrary directions. The use of non-standard images may significantly reduce the performance of face recognition system. However, there is no study on normalizing of the animal face image with arbitrary directions. In this study, we developed a light-weight angle detection and region-based convolutional network (LAD-RCNN) containing a new rotation angle coding method that can detect the rotation angle and the location of animal face in one-stage. LAD-RCNN has a frame rate of 72.74 FPS (including all steps) on a single GeForce RTX 2080 Ti GPU. LAD-RCNN has been evaluated on multiple dataset including goat dataset and gaot infrared image. Evaluation result show that the AP of face detection was more than 95% and the deviation between the detected rotation angle and the ground-truth rotation angle were less than 0.036 (i.e. 6.48{\deg}) on all the test dataset. This shows that LAD-RCNN has excellent performance on livestock face and its direction detection, and therefore it is very suitable for livestock face detection and Normalizing. Code is available at https://github.com/SheepBreedingLab-HZAU/LAD-RCNN/Comment: 8 figures, 5 table

    The double-edged role of hydrogen sulfide in the pathomechanism of multiple liver diseases

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    In mammalian systems, hydrogen sulfide (H2S)—one of the three known gaseous signaling molecules in mammals—has been found to have a variety of physiological functions. Existing studies have demonstrated that endogenous H2S is produced through enzymatic and non-enzymatic pathways. The liver is the body’s largest solid organ and is essential for H2S synthesis and elimination. Mounting evidence suggests H2S has essential roles in various aspects of liver physiological processes and pathological conditions, such as hepatic lipid metabolism, liver fibrosis, liver ischemia‒reperfusion injury, hepatocellular carcinoma, hepatotoxicity, and acute liver failure. In this review, we discuss the functions and underlying molecular mechanisms of H2S in multiple liver pathophysiological conditions

    Analysis of HIV/AIDS Epidemic and Socioeconomic Factors in Sub-Saharan Africa

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    Sub-Saharan Africa has been the epicenter of the outbreak since the spread of acquired immunodeficiency syndrome (AIDS) began to be prevalent. This article proposes several regression models to investigate the relationships between the HIV/AIDS epidemic and socioeconomic factors (the gross domestic product per capita, and population density) in ten countries of Sub-Saharan Africa, for 2011–2016. The maximum likelihood method was used to estimate the unknown parameters of these models along with the Newton–Raphson procedure and Fisher scoring algorithm. Comparing these regression models, there exist significant spatiotemporal non-stationarity and auto-correlations between the HIV/AIDS epidemic and two socioeconomic factors. Based on the empirical results, we suggest that the geographically and temporally weighted Poisson autoregressive (GTWPAR) model is more suitable than other models, and has the better fitting results

    Chemical weathering rates and controlling mechanisms of glacial catchments within different climate regimes in the Tibetan Plateau

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    Background Continental weathering plays an important role in regulating atmospheric CO2 levels. Chemical weathering in glacial areas has become an intensely focused topic in the background of global change compared with other terrestrial weathering systems. However, research on the weathering of the glacial areas in the Yarlung Tsangpo River Basin (YTRB) is still limited. Methods In this article, the major ions of the Chaiqu and Niangqu catchments in the YTRB have been investigated to illustrate the chemical weathering rates and mechanisms of the glacier areas in the YTRB. Results Ca2+ and HCO 3{}_{3}^{-} 3 − dominate the major ions of the Chaiqu and Niangqu rivers, accounting for about 71.3% and 69.2% of the TZ+ of the Chaiqu (the total cations, TZ+ = Na+ + K+ + Ca2 + + Mg2+, in µeq/L), and about 64.2% and 62.6% of the TZ+ of the Niangqu. A Monte Carlo model with six end-members is applied to quantitatively partition the dissolved load sources of the catchments. The results show that the dissolved loads of the Chaiqu and Niangqu rivers are mainly derived from carbonate weathering (accounting for about 62.9% and 79.7% of the TZ+, respectively), followed by silicate weathering (about 25.8% and 7.9% of the TZ+, respectively). The contributions of precipitation and evaporite to the Chaiqu rivers are about 5.0% and 6.2%, and those to the Niangqu rivers are about 6.3% and 6.2%. The model also calculated the proportion of sulfuric acid weathering in the Chaiqu and Niangqu catchments, which account for about 21.1% and 32.3% of the TZ+, respectively. Based on the results calculated by the model, the carbonate and silicate weathering rates in the Chaiqu catchment are about 7.9 and 1.8 ton km−2 a−1, and in the Niangqu catchment, the rates are about 13.7 and 1.5 ton km−2 a−1. The associated CO2 consumption in the Chaiqu catchment is about 4.3 and 4.4 × 104 mol km−2 a−1, and about 4.3 and 1.3 × 104 mol km−2 a−1 in the Niangqu catchment. The chemical weathering rates of the glacier areas in the YTRB show an increasing trend from upstream to downstream. Studying the weathering rates of glacier catchments in the Tibetan Plateau (TP) reveals that the chemical weathering rates of the temperate glacier catchments are higher than those of the cold glacier catchments and that lithology and runoff are important factors in controlling the chemical weathering of glacier catchments in the TP. The chemical weathering mechanisms of glacier areas in the YTRB were explored through statistical methods, and we found that elevation-dependent climate is the primary control. Lithology and glacial landforms rank second and third, respectively. Our results suggest that, above a certain altitude, climate change caused by tectonic uplift may inhibit chemical weathering. There is a more complex interaction between tectonic uplift, climate, and chemical weathering

    Chemical denudation in the Yellow River and its geomorphological implications

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    10.1016/j.geomorph.2014.12.004Geomorphology23183-9

    Ge/Si Ratio of River Water in the Yarlung Tsangpo: Implications for Hydrothermal Input and Chemical Weathering

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    Germanium/Silicon (Ge/Si) ratio is a common proxy for primary mineral dissolution and secondary clay formation yet could be affected by hydrothermal and anthropogenic activities. To decipher the main controls of riverine Ge/Si ratios and evaluate the validity of the Ge/Si ratio as a weathering proxy in the Tibetan Plateau, a detailed study was presented on Ge/Si ratios in the Yarlung Tsangpo River, southern Tibetan Plateau. River water and hydrothermal water were collected across different climatic and tectonic zones, with altitudes ranging from 800 m to 5000 m. The correlations between TDS (total dissolved solids) and the Ge/Si ratio and Si and Ge concentrations of river water, combined with the spatial and temporal variations of the Ge/Si ratio, indicate that the contribution of hydrothermal water significantly affects the Ge/Si ratio of the Yarlung Tsangpo River water, especially in the upper and middle reaches. Based on the mass balance calculation, a significant amount of Ge (11–88%) has been lost during its transportation from hydrothermal water to the river system; these could result from the incorporation of Ge on/into clays, iron hydroxide, and sulfate mineral. In comparison, due to the hydrothermal input, the average Ge/Si ratio in the Yarlung Tsangpo River is a magnitude order higher than the majority of rivers over the world. Therefore, evaluation of the contribution of hydrothermal sources should be considered when using the Ge/Si ratio to trace silicate weathering in rivers around the Tibetan Plateau

    Geochemistry of the dissolved loads during high-flow season of rivers in the southeastern coastal region of China: anthropogenic impact on chemical weathering and carbon sequestration

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    The southeastern coastal region is one of the most developed and populated areas in China. Meanwhile, it has been severely impacted by acid rain over many years. The chemical compositions and carbon isotope compositions of dissolved inorganic carbon (delta C-13(DIC)/in river water in the high-flow season were investigated to estimate the chemical weathering and associated atmospheric CO2 consumption rates as well as the acid-deposition disturbance. Mass balance calculations indicated that the dissolved loads of major rivers in the Southeast Coastal River Basin (SECRB) were contributed to by atmospheric (14.3 %, 6.6 %-23.4 %), anthropogenic (15.7 %, 0 %-41.1 %), silicate weathering (39.5 %, 17.8 %-74.0 %) and carbonate weathering inputs (30.6 %, 3.9 %-62.0 %). The silicate and carbonate chemical weathering rates for these river watersheds were 14.2-35.8 and 1.8-52.1 t km(-2) a(-1), respectively. The associated mean CO2 consumption rate by silicate weathering for the whole SECRB was 191 x 10(3) mol km(-2) a(-1). The chemical and delta C-13(DIC) evidence indicated that sulfuric and nitric acid (mainly from acid deposition) were significantly involved in the chemical weathering of rocks. There was an overestimation of CO2 consumption at 0.19 x 10(12) g Ca-1 if sulfuric and nitric acid were ignored, which accounted for about 33.6% of the total CO2 consumption by silicate weathering in the SECRB. This study quantitatively highlights the role of acid deposition in chemical weathering, suggesting that the anthropogenic impact should be seriously considered in estimations of chemical weathering and associated CO2 consumption

    Spatial and seasonal variability of organic carbon transport in the Yellow River, China

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    In this study, we examined the spatial and seasonal variability in the concentrations of dissolved and particulate organic carbon (DOC and POC) of the Yellow River. Weekly samples of water and suspended solids were collected along the main stem channel between July 2011 and July 2012 for the upstream Toudaoguai and Tongguan stations, and between August 2008 and July 2012 for the downstream Lijin station near the river mouth. The DOC export at the upstream two stations was primarily controlled by hydrological events such as melting of ice and snow with high DOC concentrations occurring in spring. In contrast, it was more affected by human activities, mainly reservoir regulation, at the lowermost Lijin station. Lower DOC concentration in the wet season indicates that most of the leachable DOC in surface soils may have largely been flushed away by spring floods. In addition, it is also likely due to dilution effect of the rapidly increased water discharge. As a result of low organic carbon content in the parent soils, the Yellow River sediments were characterized by low POC content (POC%). The averaged POC% at Toudaoguai, Tongguan, and Lijin was 0.48%, 0.47%, and 0.37%, respectively, which is significantly lower than the global mean of around 0.95%. The POC% decreased exponentially with total suspended solids (TSS) concentration. This is likely due to the dilution of riverine POC, because high TSS generally means a higher proportion of coarse sediments that have more mineral matter. During the study period, the total DOC and POC fluxes into the ocean were estimated at 0.06×1012g/yr and 0.41×1012g/yr, respectively. Combining our previous estimate of dissolved inorganic carbon (DIC) export shows that the Yellow River transports a carbon flux of 1.52×1012g/yr into the Bohai Sea, accounting for about 0.19% of the global total riverine carbon flux (DOC+POC+DIC). The extremely low DOC/POC ratio represents the lowest level among major world rivers, which is consistent with its intense soil erosion and highlights the effect of soil erosion on organic carbon export. © 2013 Elsevier B.V.Link_to_subscribed_fulltex

    CO<inf>2</inf> outgassing from the Yellow River network and its implications for riverine carbon cycle

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    ©2015. American Geophysical Union. All Rights Reserved.CO2 outgassing across water-air interface is an important, but poorly quantified, component of riverine carbon cycle, largely because the data needed for flux calculations are spatially and temporally sparse. Based on compiled data sets measured throughout the Yellow River watershed and chamber measurements on the main stem, this study investigates CO2 evasion and assesses its implications for riverine carbon cycle. Fluxes of CO2 evasion present significant spatial and seasonal variations. High effluxes are estimated in regions with intense rock weathering or severe soil erosion that mobilizes organic carbon into the river network. By integrating seasonal changes of water surface area and gas transfer velocity (k), the CO2 efflux is estimated at 7.9±1.2TgCyr-1 with a mean k of 42.1±16.9cmh-1. Unlike in lake and estuarine environments where wind is the main generator of turbulence, k is more correlated with flow velocity changes. CO2 evasion in the Yellow River network constitutes an important pathway in its riverine carbon cycling. Analyzing the watershed-scale carbon budget indicates that 35% of the carbon exported into the Yellow River network from land is degassed during fluvial transport. The CO2 efflux is comparable to the carbon burial rate, while both larger than the fluvial export to the ocean. Comparing CO2 evasion with ecosystem productivity in the Yellow River watershed shows that its ecosystem carbon sink has previously been overestimated by >50%. Present efflux estimates are associated with uncertainty, and future work is needed to mechanistically understand CO2 evasion from the highly turbid waters.Link_to_subscribed_fulltex
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