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1.
Sensors (Basel) ; 20(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183202

RESUMO

This paper introduces a new methodology for reconstructing vehicle densities of freeway segments by utilizing the limited data collected by traffic-counting sensors and developing a macroscopic traffic stream model formulated as a switched reduced-order state observer design problem with unknown or partially known inputs. Specifically, the traffic network is modeled as a hybrid dynamic system in a state space that incorporates unknown inputs. For freeway segments with traffic-counting sensors installed, vehicle densities are directly computed using field traffic count data. A reduced-order state observer is designed to analyze traffic state transitions for freeway segments without field traffic count data to indirectly estimate the vehicle densities for each freeway segment. A simulation-based experiment is performed applying the methodology and using data of a segment of Beijing Jingtong freeway in Beijing, China. The model execution results are compared with the field data associated with the same freeway segment, and highly consistent results are achieved. The proposed methodology is expected to be adopted by traffic engineers to evaluate freeway operations and develop effective management strategies.

2.
Analyst ; 143(20): 4870-4886, 2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30128460

RESUMO

Two novel highly selective quinoline-based fluorescent probes (1 and 2) with an aggregation induced emission (AIE) feature have been designed and synthesized for the rapid analysis of Cu2+ ions in aqueous media and on paper strips with a fluorescence quenching mechanism. Moreover, probes 1 and 2 exhibit excellent sensitivity and anti-interference for Cu2+ detection, and the detection limits are as low as 1.3 × 10-8 M and 8.5 × 10-8 M, respectively, which are much lower than the allowable standard of Cu2+ (∼20 µM) in drinking water (EPA). More importantly, these two probes were successfully applied for the determination of Cu2+ in real aqueous samples and fabrication of simple device test strips for rapid and on-site detection of Cu2+ ions. Interestingly, they can also be regenerated by adding an excess of S2-. Additionally, the crystallographic structure of probe 1 was confirmed through a single crystal X-ray study. Job's plot analysis and ESI-MS spectroscopic studies reflect the 1 : 1 complexation of the 1-Cu2+ and 2-Cu2+ complexes. Furthermore, DFT/TDDFT calculations were performed in order to help in understanding the electronic properties of the complexes and the chelation-induced quenching mechanism.

3.
Animals (Basel) ; 14(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38473048

RESUMO

Global climate change, habitat fragmentation, and human interference have resulted in a significant, ongoing decline in the population of goitered gazelles. Effective conservation strategies require an understanding of resource requirements of threatened species, such as dietary needs. Therefore, we aimed to elucidate the food composition and seasonal dietary changes of goitered gazelles through microhistological analyses of fresh feces. Fabaceae (11.5%), Gramineae (9.4%), Chenopodiaceae (20.2%), Asteraceae (10.1%), and Rosaceae (19.5%) formed the primary dietary components of goitered gazelle. Additionally, Krascheninnikovia arborescens (13.4%) and Prunus sibirica (16.3%) were identified as the key forage plants. Forbs (50.4%) were the predominant plants for grazing throughout the year, particularly in the spring (72.9%). The proportion of trees in the diet was highest in the autumn (36.7%) and comparatively lower in other seasons. Furthermore, the proportions of shrubs (22.0%) and graminoids (14.8%) both reached their peaks in the winter. Our findings indicate that goitered gazelles strategically forage seasonally to cope with resource bottlenecks, enhancing their adaptability to arid and semi-arid habitats. Our study provides essential ecological information for the conservation of goitered gazelles and emphasizes the importance of dietary studies of species of ecological significance in environmentally sensitive areas.

4.
Data Brief ; 49: 109423, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37501734

RESUMO

This article presents the data utilized in a study focused on identifying an optimal bus dispatching strategy in light of epidemic impacts. The study specifically examines the Xi'an Xiaozhai central business district (CBD) street network, which consists of 33 major signalized intersections and 112 bus stops associated with 12 bus routes. The dataset includes details of intersection and bus stop geospatial data, street segment and intersection design, intersection signal timing plans, bus route operational properties such as dispatching frequencies, fleet sizes, loading bay capacities, and bus-specific parameters. It also encompasses data on passenger boarding and alighting counts, as well as travelers' origin and destination (O-D) locations, routes, and departure times during three time periods: 10:00-11:00 PM, 1:00-2:00 PM, and 7:00-8:00 PM on Monday, June 7, 2021. These times represent off-peak (10:00 PM-1:00 AM the next day), adjacent-to-peak (9:00-11:00 AM, 1:00-4:00 PM, and 8:00-10:00 PM), and peak (7:00-9:00 AM, 11:00 AM-1:00 PM, and 4:00-8:00 PM) periods, respectively. Data collection involves searching government and organizational records, utilizing Alibaba Cloud's Amap platform, conducting onsite measurements, and performing a field survey. The dataset is a valuable resource for studying the integrated operations of various urban mass transit services, including buses, bus rapid transit (BRT), and fixed guideway transit, under both normal and epidemic-affected travel conditions. Additionally, it can be used to investigate multimodal integrated urban passenger services offered by automobiles, transit, ridesharing, and active transportation modes.

5.
Animals (Basel) ; 13(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36978625

RESUMO

Constant adaptation to environmental changes is required by ruminants to allow them to adapt to different ecological niches and feeding habits. In addition, the morphology and function of ruminant digestive systems reveal some adaptive evolutionary characteristics. Blue sheep (Pseudois nayaur) display a variety of morpho-physiological adaptations that are typical of grazers. In this study, we collected 64 adult blue sheep samples (whole animal carcasses) from the Helan Mountains, China, during different seasons. The external morphological parameters, digestive system morphological indexes, and rumen surface enlargement factors were determined. Our results reveal that the rumen and reticulum weights were positively correlated with the body weight (p = 0.004), while the food channel aperture, intestinal length, and weight of the blue sheep digestive tract presented no significant differences between different seasons (p > 0.05) and sexes (p > 0.05). There were significant differences (p < 0.001) in the density, length, and width of mastoids, and the rumen surface enlargement factor was 2.85 ± 1.37, which is typical of roughage feeders. The nutritional and ecological characteristics of blue sheep represent obvious morphological and physiological adaptations to an herbivorous diet. Adopting a quick foraging strategy allows blue sheep to rapidly consume and excrete large amounts of feed, thus obtaining the required energy for their activities and facilitating better adaption to environmental changes.

6.
Sci Rep ; 13(1): 5610, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019922

RESUMO

Human interventions have a great potential of spatially cornering and limiting species, therefore investigating the species distribution is one of the most crucial issues for managing wildlife populations and suggesting robust conservation strategies. Water deer (Hydropotes inermis) are widespread in China throughout history and are endemic to East Asia. However, they disappeared from Northeast China for years. We rediscovered the water deer in a previous study in Jilin Province, China. Then, we conducted further research in Northeast China to determine their distribution status, supplying fundamental data for the recovery and expansion of their population. An interview survey, line transect survey and infrared camera monitoring were carried out in some counties/cities in Northeast China from June to December 2021. The results showed that the water deer were distributed in Wuchang city of Heilongjiang Province, Changbai Korean Autonomous County, Baishan Municipal District, Ji'an city, Hunchun city, Huadian city, Antu County and Helong County of Jilin Province, Benxi Manchu Autonomous County, Huanren Manchu Autonomous County, Kuandian Manchu Autonomous County, Fengcheng city and Donggang city of Liaoning Province. The ensemble species distribution model constructed by sdm within the TSS of various models that were set as weight revealed that the potential distribution area of the water deer in the study area was 8764.66 km2 (28.77% of the study area). Combining recent studies concerning the distribution of water deer and the current study, we updated the distribution of wild water deer in Northeast China, which is vital for their conservation worldwide.


Assuntos
Cervos , Humanos , Animais , Animais Selvagens , China/epidemiologia , Ásia Oriental , Cidades
7.
Mitochondrial DNA B Resour ; 7(1): 62-63, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34926825

RESUMO

We determined the whole mtDNA genome of the Common Pochard (Aythya ferina) in the Ningxia Hui Autonomous Region, China. The complete mitochondrial genome is 16,599 bp in length and consists of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region (D-loop). The nucleotide composition is 29.34% A, 22.23% T, 15.66% G, and 32.77% C. Phylogenetic analysis results showed close genetic relationship between A. ferina and Aythya americana.

8.
Mitochondrial DNA B Resour ; 6(2): 546-547, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33628922

RESUMO

The Ferruginous Duck (Aythya nyroca) is a diving duck that is widely distributed in Asia, Africa, and Europe. We determined the complete mitogenome of the Ferruginous Duck gathered at Ningxia, China. The total length of the complete mitochondrial genome is 16,623 bp and it consists of 13 protein-coding, 22 tRNA, 2 rRNA genes, and 1 control region (CR). Only one overlap among the 13 protein-coding genes was found: ND4L/ND4. The CR is 1068 bp in length. The nucleotide composition is 29.66% A, 22.28% T, 15.35% G, 32.71% C. The result of phylogenetic analysis showed that there is close genetic relationship among Aythya nyroca and three ducks in the Genus Aythya.

9.
Mitochondrial DNA B Resour ; 6(2): 701-702, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33763555

RESUMO

We determined the whole mtDNA genome of the gray-headed lapwing (Vanellus cinereus) in Ningxia Hui Autonomous Region, China. The complete mitochondrial genome is 17,078 bp in length and consists of 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and 1 control region (D-loop). The nucleotide composition is 31.65% A, 23.50% T, 13.76% G, and 31.09% C. The result of phylogenetic analysis showed that there was close genetic relationship between V. cinereus and V. vanellus.

10.
Mitochondrial DNA B Resour ; 5(1): 586-587, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33366658

RESUMO

We determined the whole mtNDA genome of the Plateau brown frog (Rana kukunoris) in Helan Mountains, Inner Mongolia. The complete mitochondrial genome consists of 13 protein-coding, 22 tRNA, 2 rRNA genes, and 1 control region (CR), and its total length is 16,644 bp. Three overlaps among the 13 protein-coding genes were found: ATP8/ATP6, ND4L/ND4, and ND5/ND6. The CR is 837 bp in length. The nucleotide composition is 27.49% A, 29.06% T, 14.77% G, 28.68% C. The result of phylogenetic analysis showed that there was close genetic relationship between R. kukunoris and Rana chensinensis.

11.
Mitochondrial DNA B Resour ; 5(1): 922-923, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33366811

RESUMO

We determined the whole mtDNA genome of the water deer (Hydropotes inermis) in Benxi, Liaoning. The total length of the complete mitochondrial genome is 16,355 bp and it consists of 13 protein-coding, 22 tRNA, rRNA genes, and 1 control region (CR). Two overlaps among the 13 protein-coding genes were found: ND4L/ND4 and ND5/ND6. The CR is 928 bp in length. The nucleotide composition is 30.52% A, % 33.38 T, 22.77% G, and 13.32% C.

12.
Mitochondrial DNA B Resour ; 5(3): 2456-2457, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-33457825

RESUMO

We determined the whole mtDNA genome of the Spotted Nutcracker (Nucifraga caryocatactes) in Tianlong Mountain, Shan'xi Province, China. The complete mitochondrial genome is 16,914 bp in length and consists of 13 protein-coding genes (PCGS), 22 tRNA genes, 2 rRNA genes, and 1 control region (D-loops). The nucleotide composition is 25.08% A, 25.08% T, 24.75% G, and 25.08% C. The result of phylogenetic analysis showed that there was close genetic relationship between N. caryocatactes and N. columbiana. It is expected that the complete mitochondrial genome presented here will contribute to the analysis of species distribution.

13.
Integr Zool ; 15(3): 202-212, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31773863

RESUMO

The blue sheep is an endemic species to the Qinghai-Tibet Plateau and surrounding regions. It has been regarded as having 2 subspecies: Pseudois nayaur nayaur and P. n. szechuanensis. However, such a classification remains controversial. Herein, we analyze 10 microsatellite loci and part of the mitochondrial control region for clarification in such taxonomic debates. We use samples from 168 individuals from 6 geographic populations covering almost all the distribution areas of the species in China to carry out comparisons. Phylogenetic trees derived from both the microsatellite and mitochondrial markers combined with the discriminant analysis of principal components (DAPC) and the STRUCTURE analysis reveal that the individuals in the Helan Mountains are well grouped with a distinct evolutionary lineage and are significantly different from the other populations of P. n. szechuanensis according to Fst values, implying that this isolated population should be categorized as a valid subspecies; namely, Pseudois nayaur alashanicus. The isolation-by-distance (IBD) analysis shows a significant positive relationship between genetic and geographical distances among the populations.


Assuntos
Repetições de Microssatélites , Ruminantes/classificação , Animais , China , Variação Genética , Mitocôndrias/genética , Filogenia , Ruminantes/genética , Análise de Sequência de DNA/veterinária , Ovinos/classificação , Ovinos/genética
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 218: 196-205, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30995577

RESUMO

Four novel highly selective 8-hydroxyquinoline-based fluorescent chemodosimeters (1-4) were synthesized for the rapid analysis of Hg2+ in aqueous solution and on paper strips, which probably attributed to the excited state intramolecular proton transfer (ESIPT) process. Chemodosimeter 1 was evaluated as a Hg2+-ratiometric fluorescent sensor while others (2, 3 and 4) displayed fluorescence turn-on response for Hg2+ among the various survey metal ions. We demonstrated that chemodosimeters (1-4) could recognized Hg2+ ions based on a 1:1 stoichiometric binding event with fast detection time. More importantly, the detection limits for Hg2+ could reach at 10-9 M level except chemodosimeter 1 (4.05 × 10-8 M). In addition, it was found that chemodosimeters (1-4) were recycled efficiently because the Hg2+ induced emission spectra were reversed after adding NaBH4. Finally, these four sensors were successfully applied for fabrication of simple device test strips for rapid and on-site detection of Hg2+ ions.

15.
PLoS One ; 12(4): e0175840, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28414747

RESUMO

Understanding the characteristics of vessel traffic flow is crucial in maintaining navigation safety, efficiency, and overall waterway transportation management. Factors influencing vessel traffic flow possess diverse features such as hierarchy, uncertainty, nonlinearity, complexity, and interdependency. To reveal the impact mechanism of the factors influencing vessel traffic flow, a hierarchical model and a coupling model are proposed in this study based on the interpretative structural modeling method. The hierarchical model explains the hierarchies and relationships of the factors using a graph. The coupling model provides a quantitative method that explores interaction effects of factors using a coupling coefficient. The coupling coefficient is obtained by determining the quantitative indicators of the factors and their weights. Thereafter, the data obtained from Port of Tianjin is used to verify the proposed coupling model. The results show that the hierarchical model of the factors influencing vessel traffic flow can explain the level, structure, and interaction effect of the factors; the coupling model is efficient in analyzing factors influencing traffic volumes. The proposed method can be used for analyzing increases in vessel traffic flow in waterway transportation system.


Assuntos
Meios de Transporte , Humanos , Modelos Teóricos , Segurança
16.
Data Brief ; 8: 930-3, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27508245

RESUMO

This article contains data on research conducted in "A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability" (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO), and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.

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