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1.
Zool Res ; 43(1): 3-13, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34766479

RESUMO

Cenozoic tectonic evolution in the Tethyan region has greatly changed the landforms and environment of Eurasia, driving the evolution of animals and greatly affecting the diversity patterns of Eurasian animals. By combining the latest Tethyan paleogeographic models and some recently published Eurasian zoological studies, we systematically summarize how tectonic evolution in the Tethyan region has influenced the evolution and diversity patterns of Eurasian animals. The convergence of continental plates, closure of Tethys Sea, and Tethyan sea-level changes have directly affected the composition and spatial distribution of Eurasian animal diversity. The topographic and environmental changes caused by Tethyan tectonics have determined regional animal diversity in Eurasia by influencing animal origin, dispersal, preservation, diversification, and extinction. The ecological transformations resulted in the emergence of new habitats and niches, which promoted animal adaptive evolution, specialization, speciation, and expansion. We highlight that the Cenozoic tectonic evolution of the Tethyan region has been responsible for much of the alteration in Eurasian animal distribution and has been an essential force in shaping organic evolution. Furthermore, we generalize a general pattern that Tethyan geological events are linked with Eurasian animal evolution and diversity dynamics.

2.
Dev Comp Immunol ; 127: 104288, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34624358

RESUMO

Calnexin (Cnx) is a membrane-bound lectin chaperone of the endoplasmic reticulum. In this study, a novel Cnx homologue from the obscure puffer Takifugu obscurus was characterized, tentatively named ToCnx. The cDNA of ToCnx was 1803 bp, and it contained an open reading frame encoding a polypeptide of 600 amino acid residues with a calculated molecular weight of 67.5 kDa. Multiple alignment of the deduced amino acid sequences of ToCnx and other related fish Cnxs revealed that ToCnx had typical characteristics of fish Cnxs. Sequence comparison and phylogenetic tree analysis showed that ToCnx had the closest relationship with Cnxs from Takifugu flavidus and Takifugu rubripes. ToCnx transcripts were detected in all the tissues examined, and they were mainly expressed in the liver, kidney, and intestine. Upon Vibrio harveyi, Edwardsiella tarda, and Aeromonas hydrophila infection, ToCnx transcripts were all significantly upregulated in the kidneys. The recombinant calreticulin domain of ToCnx (rToCnx) was prepared by prokaryotic expression. In the absence of calcium, rToCnx was able to bind three Gram-negative bacteria (V. harveyi, E. tarda, and A. hydrophila) and two bacterial saccharides, such as lipopolysaccharide and peptidoglycan. In the presence of calcium, rToCnx could agglutinate all the detected microorganisms. In addition, rToCnx possessed the effect of inhibiting the growth of three microbe strains. These observations suggested that ToCnx is an important participant in host immune defense against bacteria.

3.
Injury ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34801246

RESUMO

BACKGROUND: The cross-sectional area of three parallel screws might affect the stability of the internal fixation of femoral neck fractures. The screws fixed in the oblique-triangle configuration (OTC) were assumed to have a larger cross-sectional area, but the biomechanical stability has not yet been validated. In this study, finite element analyses were performed to compare the biomechanical properties of the internal fixation fixed by the OTC and the traditional Inverted Equilateral Triangle Configuration (IETC). METHOD: Pauwels type III fracture was established on the three-dimensional femoral model and three cannulated screws with the OTC and traditional IETC methods were applied. The oblique-triangle configuration with the largest area inscribed the femoral neck isthmus by the three screws was determined, the area and circumference of the cross-section formed by the OTC and IETC model were compared. Stress, strain, and displacement peaks of the two configuration models under different loads were compared. Twelve pairs of nodes on the fracture ends were selected and the displacement of the fracture ends was evaluated through the displacement between these nodes. RESULTS: The area and circumference of the cross-section formed by the OTC were larger than those in the IETC model. The degree of stress dispersion around the screw holes in the OTC model was better than that of the IETC, but the stress distribution order of the three screws in the two models was consistent. The maximum stress, strain, displacement, and displacement of the fracture end in the OTC model were smaller than those in the IETC model. The stress, strain, displacement, and fracture end displacement peaks of the two fixed models gradually increase with the increase of loads. CONCLUSION: The oblique-triangle configuration showed superior mechanical properties than the IETC in finite element analyses. This study suggests that when three screws are fixed in parallel method, the larger the cross-sectional area of the screw configuration, the better stability of the internal fixation might be obtained. Furthermore, the biomechanical properties of various spatial configurations and screw holes of the three parallel screws need to be considered before clinical practice.

4.
J Neuroinflammation ; 18(1): 267, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34774071

RESUMO

BACKGROUND: Microglial polarization toward pro-inflammatory M1 phenotype are major contributors to the development of perioperative neurocognitive disorders (PNDs). Metabolic reprogramming plays an important role in regulating microglial polarization. We therefore hypothesized that surgical trauma can activate microglial M1 polarization by metabolic reprogramming to induce hippocampal neuroinflammation and subsequent postoperative cognitive impairment. METHODS: We used aged mice to establish a model of PNDs, and investigated whether surgical trauma induced metabolic reprograming in hippocampus using PET/CT and GC/TOF-MS based metabolomic analysis. We then determined the effect of the glycolytic inhibitor 2-deoxy-D-glucose (2-DG) on hippocampal microglial M1 polarization, neuroinflammation, and cognitive function at 3 d after surgery. RESULTS: We found that surgery group had less context-related freezing time than either control or anesthesia group (P < 0.05) without significant difference in tone-related freezing time (P > 0.05). The level of Iba-1 fluorescence intensity in hippocampus were significantly increased in surgery group than that in control group (P < 0.05) accompanied by activated morphological changes of microglia and increased expression of iNOS/CD86 (M1 marker) in enriched microglia from hippocampus (P < 0.05). PET/CT and metabolomics analysis indicated that surgical trauma provoked the metabolic reprogramming from oxidative phosphorylation to glycolysis in hippocampus. Inhibition of glycolysis by 2-DG significantly alleviated the surgical trauma induced increase of M1 (CD86+CD206-) phenotype in enriched microglia from hippocampus and up-regulation of pro-inflammatory mediators (IL-1ß and IL-6) expression in hippocampus. Furthermore, glycolytic inhibition by 2-DG ameliorated the hippocampus dependent cognitive deficit caused by surgical trauma. CONCLUSIONS: Metabolic reprogramming is crucial for regulating hippocampal microglial M1 polarization and neuroinflammation in PNDs. Manipulating microglial metabolism might provide a valuable therapeutic strategy for treating PNDs.

5.
Microbiome ; 9(1): 226, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34784980

RESUMO

BACKGROUND: Parkinson's disease (PD) is a prevalent neurodegenerative disorder, displaying not only well-known motor deficits but also gastrointestinal dysfunctions. Consistently, it has been increasingly evident that gut microbiota affects the communication between the gut and the brain in PD pathogenesis, known as the microbiota-gut-brain axis. As an approach to re-establishing a normal microbiota community, fecal microbiota transplantation (FMT) has exerted beneficial effects on PD in recent studies. Here, in this study, we established a chronic rotenone-induced PD mouse model to evaluate the protective effects of FMT treatment on PD and to explore the underlying mechanisms, which also proves the involvement of gut microbiota dysbiosis in PD pathogenesis via the microbiota-gut-brain axis. RESULTS: We demonstrated that gut microbiota dysbiosis induced by rotenone administration caused gastrointestinal function impairment and poor behavioral performances in the PD mice. Moreover, 16S RNA sequencing identified the increase of bacterial genera Akkermansia and Desulfovibrio in fecal samples of rotenone-induced mice. By contrast, FMT treatment remarkably restored the gut microbial community, thus ameliorating the gastrointestinal dysfunctions and the motor deficits of the PD mice. Further experiments revealed that FMT administration alleviated intestinal inflammation and barrier destruction, thus reducing the levels of systemic inflammation. Subsequently, FMT treatment attenuated blood-brain barrier (BBB) impairment and suppressed neuroinflammation in the substantia nigra (SN), which further decreased the damage of dopaminergic neurons. Additional mechanistic investigation discovered that FMT treatment reduced lipopolysaccharide (LPS) levels in the colon, the serum, and the SN, thereafter suppressing the TLR4/MyD88/NF-κB signaling pathway and its downstream pro-inflammatory products both in the SN and the colon. CONCLUSIONS: Our current study demonstrates that FMT treatment can correct the gut microbiota dysbiosis and ameliorate the rotenone-induced PD mouse model, in which suppression of the inflammation mediated by the LPS-TLR4 signaling pathway both in the gut and the brain possibly plays a significant role. Further, we prove that rotenone-induced microbiota dysbiosis is involved in the genesis of PD via the microbiota-gut-brain axis. Video abstract.

6.
J Healthc Eng ; 2021: 2869488, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745494

RESUMO

Lumbar disc herniation is one of the common clinical diseases of the lower lumbar spine in orthopedics. The purpose is to remove the herniated disc nucleus pulposus tissue, remove the compressed part of the disease, and relieve symptoms, such as nerve pain. In the past, biomechanics research mostly relied on in vitro measurements, but the complicated internal environment of the human body prevented us from further measurement and research. However, with the development of computer technology, the use of computer CT scanning, software three-dimensional reconstruction, and displacement study three-dimensional spine biomechanics method makes the research of biomechanics into in vitro simulation stage and has gradually become the focus of current research. The postoperative biomechanics was simulated and the comparison model was established at the same time. At the same time, we combined the clinical follow-up data and studied the clinical data for the treatment of postoperative recurrence of lumbar disc herniation. We compared and analyzed the initial operation method and the experimental results and obtained the prevention of recurrence. The results showed that when one inferior articular process was removed, the lumbar spine appeared unstable to rotate to the opposite side; when one inferior articular process was completely removed, the movement of the lumbar spine in all directions was unstable. Better research on the biomechanical properties of the spine will help the diagnosis and treatment of clinical lumbar disc herniation. Therefore, when performing posterior lumbar spine surgery, not only should the exposure of the surgical field and thorough decompression be considered, but also the biomechanical properties of the lumbar spine should be comprehensively evaluated.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Idoso , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Pessoa de Meia-Idade , Resultado do Tratamento
7.
PLoS Pathog ; 17(11): e1009728, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34780577

RESUMO

The accessory protein Nef of human and simian immunodeficiency viruses (HIV and SIV) is an important pathogenicity factor known to interact with cellular protein kinases and other signaling proteins. A canonical SH3 domain binding motif in Nef is required for most of these interactions. For example, HIV-1 Nef activates the tyrosine kinase Hck by tightly binding to its SH3 domain. An archetypal contact between a negatively charged SH3 residue and a highly conserved arginine in Nef (Arg77) plays a key role here. Combining structural analyses with functional assays, we here show that Nef proteins have also developed a distinct structural strategy-termed the "R-clamp"-that favors the formation of this salt bridge via buttressing Arg77. Comparison of evolutionarily diverse Nef proteins revealed that several distinct R-clamps have evolved that are functionally equivalent but differ in the side chain compositions of Nef residues 83 and 120. Whereas a similar R-clamp design is shared by Nef proteins of HIV-1 groups M, O, and P, as well as SIVgor, the Nef proteins of SIV from the Eastern chimpanzee subspecies (SIVcpzP.t.s.) exclusively utilize another type of R-clamp. By contrast, SIV of Central chimpanzees (SIVcpzP.t.t.) and HIV-1 group N strains show more heterogenous R-clamp design principles, including a non-functional evolutionary intermediate of the aforementioned two classes. These data add to our understanding of the structural basis of SH3 binding and kinase deregulation by Nef, and provide an interesting example of primate lentiviral protein evolution.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34809420

RESUMO

Carbon dioxide (CO2) sensing using an optical technique is of great importance in the environment and industrial emission monitoring. However, limited by the poor specific adsorption of gas molecules as well as insufficient coupling efficiency, there is still a long way to go toward realizing a highly sensitive optical CO2 gas sensor. Herein, by combining the advantages of a whispering-gallery-mode microcavity and a metal-organic framework (MOF) film, a porous functional microcavity (PF-MC) was fabricated with the assistance of the atomic layer deposition technique and was applied to CO2 sensing. In this functional composite, the rolled-up microcavity provides the ability to tune the propagation of light waves and the electromagnetic coupling with the surroundings via an evanescent field, while the nanoporous MOF film contributes to the specific adsorption of CO2. The composite demonstrates a high sensitivity of 188 nm RIU-1 (7.4 pm/% with respect to the CO2 concentration) and a low detection limit of ∼5.85 × 10-5 RIU. Furthermore, the PF-MC exhibits great selectivity to CO2 and outstanding reproducibility, which is promising for the next-generation optical gas sensing devices.

9.
Ann Transl Med ; 9(18): 1482, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34734034

RESUMO

Background: Recent evidence has emerged concerning hypoglycemia following the application of glucagon-like peptide-1 receptor agonists (GLP-1RAs). Nevertheless, few real-world investigations have been performed to determine the clinical characteristics, onset, and outcomes of hypoglycemia associated with different GLP-1RAs. This study aimed to compare and assess the relationship between various GLP-1RAs and hypoglycemia in a large population based on updated data from the Food and Drug Administration Adverse Event Reporting System (FAERS). Methods: Bayesian and disproportionality analyses were applied to data mining in order to investigate suspected cases of hypoglycemia following various GLP-1RAs using the FAERS data between January 2004 and September 2020. We also evaluated the onset time, fatality risks, and hospitalization proportions of GLP-1RA-related hypoglycemia. Results: We identified 1,164 GLP-1RA-associated hypoglycemia cases, which seemed to affect more middle-aged patients than elderly ones. Also, females were more affected than males. Lixisenatide demonstrated a stronger association with hypoglycemia compared to other GLP-1RAs, according to the highest reporting odds ratio (ROR) (28.03, 95% confidence interval =15.92, 49.32), empirical Bayes geometric mean [26.00, 95% confidence interval (CI): 16.20], and proportional reporting ratio (PRR) (26.01, χ2=313.37). The median time to hypoglycemia onset was 5 days (interquartile range, 0-67.75 days) following GLP-1RA treatment. In general, GLP-1RA-associated hypoglycemia resulted in fatality and hospitalization proportions of 3.53% and 56.08%, respectively. Conclusions: By analyzing the FAERS data, we outlined the association between hypoglycemia and different GLP-1RAs in greater detail in terms of clinical features, onset, and outcomes. Among all six GLP-1RAs, lixisenatide demonstrated the strongest association with hypoglycemia while no relationship between albiglutide and hypoglycemia was observed. Attention should be given to GLP-1RAs when used in patients with high risks of hypoglycemia.

10.
Neurosci Bull ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34773221

RESUMO

Mutations of the X-linked methyl-CpG-binding protein 2 (MECP2) gene in humans are responsible for most cases of Rett syndrome (RTT), an X-linked progressive neurological disorder. While genome-wide screens in clinical trials have revealed several putative RTT-associated mutations in MECP2, their causal relevance regarding the functional regulation of MeCP2 at the etiologic sites at the protein level requires more evidence. In this study, we demonstrated that MeCP2 was dynamically modified by O-linked-ß-N-acetylglucosamine (O-GlcNAc) at threonine 203 (T203), an etiologic site in RTT patients. Disruption of the O-GlcNAcylation of MeCP2 specifically at T203 impaired dendrite development and spine maturation in cultured hippocampal neurons, and disrupted neuronal migration, dendritic spine morphogenesis, and caused dysfunction of synaptic transmission in the developing and juvenile mouse cerebral cortex. Mechanistically, genetic disruption of O-GlcNAcylation at T203 on MeCP2 decreased the neuronal activity-induced induction of Bdnf transcription. Our study highlights the critical role of MeCP2 T203 O-GlcNAcylation in neural development and synaptic transmission potentially via brain-derived neurotrophic factor.

11.
Analyst ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783327

RESUMO

Rapid and accurate detection of pesticide and veterinary drug residues is a continuing challenge because of the complex matrix effects. Thus, appropriate sample pretreatment is a crucial step for the effective extraction of the analytes and removal of the interferences. Recently, the development of nanomaterial adsorbents has greatly promoted the innovation of food sample pretreatment approaches. Porous organic frameworks (POFs), including polymers of intrinsic microporosity, covalent organic frameworks, hyper crosslinked polymers, conjugated microporous polymers, and porous aromatic frameworks, have been widely utilized due to their tailorable skeletons and pores as well as fascinating features. This review summarizes the recent advances for POFs to be utilized in adsorption and sample preparation of pesticide and veterinary drug residues. In addition, future prospects and challenges are discussed, hoping to offer a reference for further study on POFs in sample pretreatment.

12.
Biomed Mater ; 17(1)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34749352

RESUMO

The construction of microvascular network is one of the greatest challenges for tissue engineering and cell therapy. Endothelial cells are essential for the construction of network of blood vessels. However, their application meets challenges in clinic due to the limited resource of autologous endothelium. Mesenchymal stem cells can effectively promote the angiogenesis in ischemic tissues for their abilities of endothelial differentiation and paracrine, and abundant sources. Extracellular matrix (ECM) has been widely used as an ideal biomaterial to mimic cellular microenvironment for tissue engineering due to its merits of neutrality, good biocompatibility, degradability, and controllability. In this study, a functional cell derived ECM biomaterial enriched with VEGFA and bFGF by expressing the collagen-binding domain fused factor genes in host cells was prepared. This material could induce endothelial differentiation of human umbilical cord mesenchymal stem cells (hUCMSCs) and promote angiogenesis, which may improve the healing effect of skin injury. Our research not only provides a functional ECM material to inducing angiogenesis by inducing endothelial differentiation of hUCMSCs, but also shed light on the ubiquitous approaches to endow ECM materials different functions by enriching different factors. This study will benefit tissue engineering and regenerative medicine researches.

13.
Dis Markers ; 2021: 7842035, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777634

RESUMO

Pancreatic adenocarcinoma (PAAD) is an extremely lethal disease worldwide. Brain-derived neurotrophic factor (BDNF) is a critical member of the neurotrophin polypeptide superfamily that plays an important role in multiple cancers. However, the association among BDNF expression, tumor immunity, and PAAD prognosis remains unclear. BDNF expression and its influence on patient prognosis were explored based on The Cancer Genome Atlas, Cancer Cell Line Encyclopedia, Genotype-Tissue Expression, and Kaplan-Meier plotter. Gene set enrichment analysis was performed to understand the biological roles of BDNF. The role of BDNF in tumor-infiltrating immune cells was determined using the Tumor Immune Estimation Resource database and the single-sample gene set enrichment analysis and xCell algorithm. The correlation among BDNF and chemokines, chemokine receptors, chemotherapeutic efficacy, and immune checkpoints was analyzed based on RStudio. BDNF expression was remarkably higher in PAAD compared to their paired normal tissues, and high BDNF expression was associated with unfavorable prognosis. Enrichment analysis revealed that BDNF was significantly enriched in major oncogenic pathways in PAAD. BDNF expression was positively correlated with immune infiltration, especially Th2 cells. Moreover, BDNF expression was positively correlated with Th2 cell-related chemokine/chemokine receptors, indicating that BDNF might modulate the migration of Th2 cells in PAAD. We also found that BDNF expression was correlated with high chemotherapeutics sensitivity and highly expressed immune checkpoints, making it a valuable biomarker in predicting the therapeutic benefits for chemotherapy and immunotherapy in cancer patients. In summary, BDNF might affect patient prognosis by interacting with tumor-infiltrating Th2 cells, thus serving as a potential prognostic biomarker in PAAD.

14.
ACS Omega ; 6(39): 25749-25761, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632231

RESUMO

Ethanol is usually combined with gasoline to manufacture ethanol-gasoline with excellent combustion characteristics. However, extracting water from hydrous ethanol to manufacture anhydrous ethanol consumed much energy, which increases the production cost of ethanol-gasoline. Many researchers have studied the combustion and emissions of hydrous ethanol-gasoline to explore the application of hydrous ethanol-gasoline as the fuel for spark-ignition engines. Most previous studies changed the hydrous ethanol ratio with fixed purity in hydrous ethanol-gasoline to study the effects of hydrous ethanol. Different from previous studies, this paper studied the effects of water ratio (Wr) in hydrous ethanol on the combustion and emissions of a hydrous ethanol/gasoline combined injection engine under different excess air ratio (λ) values. The ratios of ethanol and gasoline keep constant, while the purity of hydrous ethanol changes during the research. The experiment adopted the combined injection mode with hydrous ethanol direct injection plus gasoline port injection; the direct injection ratio was 20%. The experiment set three λ (0.9, 1, and 1.2) and five Wrs (0, 5, 10, 15, and 20%). The test engine's speed was 1500 rpm, and the intake manifold absolute pressure was 48 kPa. Results showed that water inhibited combustion, prolonged CA 0-10 and CA 10-90, reduced P max and T max, and delayed APmax; larger λ made the deterioration on combustion more obvious, and the smaller λ had a larger tolerance to water. Water could increase torque and improve emissions, but different parameters corresponded to different optimal Wrs. For torque, the optimal Wr was 5%. For HC emissions, the optimal Wr was 0%; for CO emissions, the optimal value was 5%; and for NO x emissions, the best value was 20%. The best Wr was 10% for particle number (PN) emissions. Under the optimal Wr condition, when λ values were 0.9, 1, and 1.2, compared with pure gasoline, the torque increased by 7.5, 5.54, and 5.31%; HC emissions decreased by 21.37, 23.43, and 26.58%; NO x emissions decreased by 4.26, 11.47, and 12.55%; CO emissions decreased by 17.51, 34.56, -50%; and the total PN emissions decreased by 87.64, 89.64, and 76.07%.

15.
Nano Lett ; 21(20): 8764-8769, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34613736

RESUMO

Ionic conductivity enables the technologies of fuel cells, electrolysis cells, and batteries. However, the ambiguous origins of the extraordinary ionic conductivity impede its implementation in heterostructure films for the devices. Here, we disclosed that the extraordinary ionic and electronic conductivities come from field effect. We found in Ce0.8Gd0.2O2-δ (CGO)/Zr0.85Y0.15O2-δ (YSZ) heterostructures that the ionic conductivity of CGO layer (n-i conductor) and the electronic conductivity of YSZ layer (p-i conductor) exponentially increased with potential. The potential occurred from electron transfer and stoichiometric polarization in p-i-n junction. Field effect ionic conductivity contributed the major increment in the maximum power density. The results demonstrated field effect ionic and electronic conductivities, their dependences on heterostructures, and impacts on fuel cells.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34695001

RESUMO

Adaptive inference has been proven to improve bidirectional encoder representations from transformers (BERT)'s inference speed with minimal loss of accuracy. However, current work only focuses on the BERT model and lacks exploration of other pretrained language models (PLMs). Therefore, this article conducts an empirical study on the application of adaptive inference mechanism in various PLMs, including generative pretraining (GPT), GCNN, ALBERT, and TinyBERT. This mechanism is verified on both English and Chinese benchmarks, and experimental results demonstrated that it is able to speed up by a wide range from 1 to 10 times if given different speed thresholds. In addition, its application on ALBERT shows that adaptive inference can work with parameter sharing, achieving model compression and acceleration simultaneously, while the application on TinyBERT proves that it can further accelerate the distilled small model. As for the problem that too many labels make adaptive inference invalid, this article also proposes a solution, namely label reduction. Finally, this article open-sources an easy-to-use toolkit called FastPLM to help developers adopt pretrained models with adaptive inference capabilities in their applications.

17.
Artigo em Inglês | MEDLINE | ID: mdl-34639801

RESUMO

Rapid economic growth has a significant impact on land use change, which would threaten the natural ecology. Zhangye city of the Heihe River Basin, China is an ecologically vulnerable region where land use changes significantly due to socioeconomic development and population increases. The study employed a computable general equilibrium of land use change (CGELUC) model to simulate land use change and then used a dynamic land system (DLS) model to spatialize land use change during 2015-2030 under three development scenarios in Zhangye city. The three development scenarios are the baseline scenario (BAU), the resource consumption scenario (RCS) and the green development scenario (GDS). We found that economic growth would lead to land demand increases in high value-added industries and decreases in low value-added industries. The cultivated land would decrease while the built-up area would increase. By 2030, the cultivated land will decrease by 8.16%, 10.89% and 4.16%, respectively, under BAU, RCS and GDS, while the built-up area will increase by 8.61%, 10.39% and 4.75%, respectively. The expansion of built-up area under RCS presents spatial characteristics of centralized distribution, while spatial characteristics of uniform discrete distributions are presented under GDS. The expansion of ecological land under GDS would be considerable, especially in the north of Sunan County and Gaotai County, and around the natural reserve of Ganzhou County. This paper provides a scientific reference for coordinating economic development and ecological protection in the rapidly developing urbanized areas in western China.


Assuntos
Conservação dos Recursos Naturais , Rios , China , Ecossistema , Desenvolvimento Sustentável
18.
Biology (Basel) ; 10(10)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34681097

RESUMO

BACKGROUND: Anopheles philippinensis and Anopheles nivipes are morphologically similar and are considered to be effective vectors of malaria transmission in northeastern India. Environmental factors such as temperature and rainfall have a significant impact on the temporal and spatial distribution of disease vectors driven by future climate change. METHODS: In this study, we used the maximum entropy model to predict the potential global distribution of the two mosquito species in the near future and the trend of future distribution in China. Based on the contribution rate of environmental factors, we analyzed the main environmental factors affecting the distribution of the two mosquito species. We also constructed a disease vector risk assessment index system to calculate the comprehensive risk value of the invasive species. RESULTS: Precipitation has a significant effect on the distribution of potentially suitable areas for Anopheles philippinensis and Anopheles nivipes. The two mosquito species may spread in the suitable areas of China in the future. The results of the risk assessment index system showed that the two mosquito species belong to the moderate invasion risk level for China. CONCLUSIONS: China should improve the mosquito vector monitoring system, formulate scientific prevention and control strategies and strictly prevent foreign imports.

19.
Biology (Basel) ; 10(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34681156

RESUMO

Amblyomma americanum (the lone star tick) is a pathogen vector, mainly from eastern North America, that bites humans. With global integration and climate change, some ticks that are currently confined to a certain place may begin to spread out; some reports have shown that they are undergoing rapid range expansion. The difference in the potential geographic distribution of A. americanum under current and future climatic conditions is dependent on environment variables such as temperature and precipitation, which can affect their survival. In this study, we used a maximum entropy (MaxEnt) model to predict the potential geographic distribution of A. americanum. The MaxEnt model was calibrated at the native range of A. americanum using occurrence data and the current climatic conditions. Seven WorldClim climatic variables were selected by the jackknife method and tested in MaxEnt using different combinations of model feature class functions and regularization multiplier values. The best model was chosen based on the omission rate and the lowest Akaike information criterion. The resulting model was then projected onto the global scale using the current and future climate conditions modeled under four greenhouse gas emission scenarios.

20.
Opt Lett ; 46(19): 4722-4725, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598183

RESUMO

We investigate the modal properties of a beam carrying orbital angular momentum (OAM) generated by a circular array (ring) of multiple micro-ring emitters (rings) analytically and via simulation. In such a "ring-of-rings" structure, N emitters generate N optical vortex beams with the same OAM-order l0 at the same wavelength. The output beam is a coherent combination of the N vortex beams located at different azimuthal positions, having the same radial displacement. We derive an analytical expression for the output optical field and calculate the OAM-order power spectrum of the generated beam. The analytical expression and simulation results show that (1) the OAM spectrum of the output beam composes equidistant OAM spectral components, symmetrically surrounding l0 with a spacing equal to N; (2) the envelope of the OAM spectrum broadens with an increased radius of the circular array or the value of l0; and (3) the OAM components of the generated beam could be tuned either by changing the value of l0, corresponding to different spectrum envelopes, or by adding different linear phase delays to the micro-ring emitters, which does not affect the envelope of the OAM spectrum.

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