Plant-frugivore network simplification under habitat fragmentation leaves a small core of interacting generalists

Habitat fragmentation impacts seed dispersal processes that are important in maintaining biodiversity and ecosystem functioning. However, it is still unclear how habitat fragmentation affects frugivorous interactions due to the lack of high-quality data on plant-frugivore networks. Here we recorded 10,117 plant-frugivore interactions from 22 reservoir islands and six nearby mainland sites using the technology of arboreal camera trapping to assess the effects of island area and isolation on the diversity, structure, and stability of plant-frugivore networks. We found that network simplification under habitat fragmentation reduces the number of interactions involving specialized species and large-bodied frugivores. Small islands had more connected, less modular, and more nested networks that consisted mainly of small-bodied birds and abundant plants, as well as showed evidence of interaction release (i.e., dietary expansion of frugivores). Our results reveal the importance of preserving large forest remnants to support plant-frugivore interaction diversity and forest functionality.Fil: Li, Wande. East China Normal University; ChinaFil: Zhu, Chen. College Of Life Sciences, Zhejiang University; ChinaFil: Grass, Ingo. Universidad de Hohenheim; AlemaniaFil: Vazquez, Diego P.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de las Zonas Áridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de las Zonas Áridas; ArgentinaFil: Wang, Duorun. East China Normal University; ChinaFil: Zhao, Yuhao. East China Normal University; ChinaFil: Zeng, Di. East China Normal University; ChinaFil: Kang, Yi. East China Normal University; ChinaFil: Ding, Ping. No especifíca;Fil: Si, Xingfeng. East China Normal University; Chin

Ground-Based Polarimetric Remote Sensing of Dust Aerosol Properties in Chinese Deserts near Hexi Corridor

One-year observation of dust aerosol properties near Hexi Corridor was obtained from polarimetric measurements by ground-based sunphotometer in the county of Minqin in northwestern China from March 2012 to February 2013. We observed an annual mean AOD of 0.22±0.22 at 0.50 μm and Ångström exponents of 0.1–1.0 fitting a bimode normal distribution centered at 0.18 and 0.50, respectively. The effective radii of fine (0.13–0.17 μm) and coarse (2.49–3.49 μm) modes were found stable at all seasons together with the appearance of a third mode of particle radius at 0.4–1.0 μm when AOD was larger than 0.6. It is noticeable that the real (1.5–1.7) and imaginary (0.0005 to 0.09) parts of complex refractive indices were higher than other studies performed in other desert regions of China, while single scattering albedo was relatively lower (~0.84–0.89) at wavelengths of 0.44, 0.67, 0.87, and 1.02 μm. This is partially due to calcite or hematite in the soil in Minqin or the influence of anthropogenic aerosols containing carbon. Moreover, from our novel polarimetric measurement, the scattering phase function (F11) and degree of linear polarization for incident unpolarized light (-F12/F11) of dust aerosols were also obtained within this deserted area

High Genetic Diversity and Low Differentiation of Michelia coriacea (Magnoliaceae), a Critically Endangered Endemic in Southeast Yunnan, China

Michelia coriacea, a critically endangered tree, has a restricted and fragmented distribution in Southeast Yunnan Province, China. The genetic diversity, genetic structure and gene flow in the three extant populations of this species were detected by 10 inter-simple sequence repeat (ISSR) markers and 11 simple sequence repeat (SSR) markers. Examination of genetic diversity revealed that the species maintained a relatively high level of genetic diversity at the species level (percentage of polymorphic bands) PPB = 96.36% from ISSRs; PPL (percentage of polymorphic loci) = 95.56% from SSRs, despite several fragmental populations. Low levels of genetic differentiation among the populations of M. coriacea were detected by Nei’s Gst = 0.187 for ISSR and Wright’s Fst = 0.090 for SSR markers, which is further confirmed by Bayesian model-based STRUCTURE and PCoA analysis that could not reveal a clear separation between populations, although YKP was differentiated to other two populations by ISSR markers. Meanwhile, AMOVA analysis also indicated that 22.84% and 13.90% of genetic variation existed among populations for ISSRs and SSRs, respectively. The high level of genetic diversity, low genetic differentiation, and the population, structure imply that the fragmented habitat and the isolated population of M. coriacea may be due to recent over-exploitation. Conservation and management of M. coriacea should concentrate on maintaining the high level of genetic variability through both in and ex-situ conservation actions

Unsupervised discovery of solid-state lithium ion conductors

Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Although machine learning has gained great interest in the discovery of functional materials, the advancement of reliable models is impeded by the scarcity of available materials property data. Here we propose and demonstrate a distinctive approach for materials discovery using unsupervised learning, which does not require labeled data and thus alleviates the data scarcity challenge. Using solid-state Li-ion conductors as a model problem, unsupervised materials discovery utilizes a limited quantity of conductivity data to prioritize a candidate list from a wide range of Li-containing materials for further accurate screening. Our unsupervised learning scheme discovers 16 new fast Li-conductors with conductivities of 10−4–10−1 S cm−1 predicted in ab initio molecular dynamics simulations. These compounds have structures and chemistries distinct to known systems, demonstrating the capability of unsupervised learning for discovering materials over a wide materials space with limited property data

Air Quality over China

The strong economic growth in China in recent decades, together with meteorological factors, has resulted in serious air pollution problems, in particular over large industrialized areas with high population density. To reduce the concentrations of pollutants, air pollution control policies have been successfully implemented, resulting in the gradual decrease of air pollution in China during the last decade, as evidenced from both satellite and ground-based measurements. The aims of the Dragon 4 project “Air quality over China” were the determination of trends in the concentrations of aerosols and trace gases, quantification of emissions using a top-down approach and gain a better understanding of the sources, transport and underlying processes contributing to air pollution. This was achieved through (a) satellite observations of trace gases and aerosols to study the temporal and spatial variability of air pollutants; (b) derivation of trace gas emissions from satellite observations to study sources of air pollution and improve air quality modeling; and (c) study effects of haze on air quality. In these studies, the satellite observations are complemented with ground-based observations and modeling

GLUT3 expression in cystic change induced by hypoxia in pituitary adenomas

Tumor cells require large amounts of energy to sustain growth. Through the mediated transport of glucose transporters, the uptake and utilization of glucose by tumor cells are significantly enhanced in the hypoxic microenvironment. Pituitary adenomas are benign tumors with high-energy metabolisms. We aimed to investigate the role of expression of glucose transporter 3 (GLUT3) and glucose transporter 1 (GLUT1) in pituitary adenomas, including effects on size, cystic change and hormone type. Pituitary adenomas from 203 patients were collected from January 2013 to April 2017, and immunohistochemical analysis was used to detect the expression of GLUT3 and GLUT1 in tumor specimens. GLUT3-positive expression in the cystic change group was higher than that in the non-cystic change group (P = 0.018). Proportions of GLUT3-positive staining of microadenomas, macroadenomas, and giant adenomas were 22.7 (5/22), 50.4 (66/131) and 54.0% (27/50), respectively (P = 0.022). In cases of prolactin adenoma, GLUT3-positive staining was predominant in cell membranes (P = 0.000006), while in cases of follicle-stimulating hormone or luteotropic hormone adenoma, we found mainly paranuclear dot-like GLUT3 staining (P = 0.025). In other hormonal adenomas, GLUT3 was only partially expressed, and the intensity of cell membrane or paranuclear punctate staining was weak. In contrast to GLUT3, GLUT1 expression was not associated with pituitary adenomas. Thus, our results indicate that the expression of GLUT3 in pituitary adenomas is closely related to cystic change and hormonal type. This study is the first to report a unique paranuclear dot-like GLUT3 staining pattern in pituitary adenomas

Neural Network AEROsol Retrieval for Geostationary Satellite (NNAeroG) Based on Temporal, Spatial and Spectral Measurements

Geostationary satellites observe the earth surface and atmosphere with a short repeat time, thus, providing aerosol parameters with high temporal resolution, which contributes to the air quality monitoring. Due to the limited information content in satellite data, and the coupling between the signals received from the surface and the atmosphere, the accurate retrieval of multiple aerosol parameters over land is difficult. With the strategy of taking full advantage of satellite measurement information, here we propose a neural network AEROsol retrieval framework for geostationary satellite (NNAeroG), which can potentially be applied to different instruments to obtain various aerosol parameters. NNAeroG was applied to the Advanced Himawari Imager on Himawari-8 and the results were evaluated versus independent ground-based sun photometer reference data. The aerosol optical depth, Ångström exponent and fine mode fraction produced by the NNAeroG method are significantly better than the official JAXA aerosol products. With spectral bands selection, the use of thermal infrared bands is meaningful for aerosol retrieval

Seasonal and daily variations in the occurence and outcomes of acute Stanford type A dissections: a retrospective single-center study

Abstract Background To investigate the seasonal, monthly, and daily distributions of the incidence of Stanford type-A acute aortic dissection (TAAAD) and identify seasonality in the duration of hospital stay and in-hospital mortality of TAAAD in south-eastern China. Methods We enrolled patients diagnosed with TAAAD between 1 June 2017 and 31 May 2021. Participants were divided into seasonal, monthly, and daily groups according to the need for analysis. Analysis of variance was applied to compare the number of TAAAD in different seasons, months, and days. χ2 test was used to compare in-hospital mortality among the four groups. Non-parametric methods were used for all comparisons of the duration of hospital stay. Univariate logistic and multivariable logistic regression analyses were performed to assess the duration of hospital stay. Results Of the 485 patients, 154 were diagnosed in winter (31.8%), 115 in spring (23.7%), 73 in summer (15.1%), and 143 in autumn (29.5%). The daily, monthly, and seasonal distributions of TAAAD were significantly different (P = 0.04, P < 0.01, and P < 0.01, respectively). This study did not identify any significant decrease in maximal, mean, or minimum temperatures between the three days before TAAAD and the day of TAAAD. No seasonal variations associated with in-hospital mortality was observed (P = 0.89). However, significant differences were observed in the seasonal distribution of the duration of hospital stay for TAAAD [winter was 17.0 (4.0–24.0) days, spring was 20.0 (14.0–29.0) days, summer was 20.0 (12.5–31.0) days, and autumn was 20.0 (13.0–30.0) days, P < 0.01]. Multiple factor analysis showed that winter was the independent risk factor for the increased duration of hospital stay. The odds ratio for winter was 2.21 (1.46, 3.33, P < 0.01). Conclusions Our study confirmed that the incidence of TAAAD exhibits seasonal, monthly, and daily variations in south-eastern China. Moreover, the daily incidence of TAAAD is higher on weekdays than that on weekends