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1.
J Environ Manage ; 353: 120262, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38330840

RESUMEN

Land reclamation is a widely adopted method for managing land shortage and promoting coastal economic development globally. However, its impacts on biodiversity vary based on distinct reclamation histories and land use management strategies in different regions. This study aims to examine the effects of reclamation history and land use types at different spatial scales on anuran communities in coastal reclaimed land, which are an important taxon in the coastal ecosystem. We used visual and acoustic encounter methods to survey anurans in 2016 and 2017 across 20 1-km radius coastal land reclamation landscapes with different reclamation histories (10, 20, and 60 y after reclamation) in Nanhui Dongtan of Shanghai, an important coastal land reclamation region along the Yangtze River Estuary. Landscape variables (farmlands, woodlands, and impermeable surface covers, and the landscape Shannon diversity index) at four different spatial scales (250 m, 500 m, 750 m and 1000 m) and water salinity in each landscape were measured. Our findings reveal differences in anuran communities between study sites with 10, 20, and 60 years of reclamation history. Abundances of the ornamented pygmy frog (Microhyla fissipes) and Beijing gold-striped pond frog (Pelophylax plancyi) in landscapes with a 10-year reclamation history were significantly lower compared to those with histories of 20 and 60 years. Zhoushan toad (Bufo gargarizans) abundance was significantly negatively related to farmland cover at the 1000 m scale and impermeable surface cover at the 250 m scale; Hong Kong rice-paddy frog (Fejervarya multistriata) abundance was significantly positively related to farmland cover at the 1000 m scale; ornamented pygmy frog abundance was positively related to farmland cover at the 1000 m scale; and Beijing gold-striped pond frog abundance was significantly positively and negatively related to the landscape Shannon diversity index at the 1000 m scale and to water salinity, respectively. Amphibians quickly migrated and colonized coastal reclaimed land from older natural lands. However, two anuran species with specific habitat requirements tended to avoid areas with shorter reclamation histories. The single-species models revealed different responses to various land uses at the various scales, which indicated that land use management was important to amphibian conservation in coastal reclamation regions.


Asunto(s)
Biodiversidad , Ecosistema , Animales , China , Anuros , Agua , Conservación de los Recursos Naturales/métodos
2.
Viruses ; 15(5)2023 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-37243207

RESUMEN

Avian coronaviruses (ACoV) have been shown to be highly prevalent in wild bird populations. More work on avian coronavirus detection and diversity estimation is needed for the breeding territories of migrating birds, where the high diversity and high prevalence of Orthomyxoviridae and Paramyxoviridae have already been shown in wild birds. In order to detect ACoV RNA, we conducted PCR diagnostics of cloacal swab samples from birds, which we monitored during avian influenza A virus surveillance activities. Samples from two distant Asian regions of Russia (Sakhalin region and Novosibirsk region) were tested. Amplified fragments of the RNA-dependent RNA-polymerase (RdRp) of positive samples were partially sequenced to determine the species of Coronaviridae represented. The study revealed a high presence of ACoV among wild birds in Russia. Moreover, there was a high presence of birds co-infected with avian coronavirus, avian influenza virus, and avian paramyxovirus. We found one case of triple co-infection in a Northern Pintail (Anas acuta). Phylogenetic analysis revealed the circulation of a Gammacoronavirus species. A Deltacoronavirus species was not detected, which supports the data regarding the low prevalence of deltacoronaviruses among surveyed bird species.


Asunto(s)
Avulavirus , Gammacoronavirus , Virus de la Influenza A , Gripe Aviar , Animales , Patos , Gammacoronavirus/genética , Gripe Aviar/epidemiología , Avulavirus/genética , Siberia/epidemiología , Filogenia , Aves , Animales Salvajes , Virus de la Influenza A/genética , ARN
3.
Infect Dis Poverty ; 12(1): 35, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041630

RESUMEN

BACKGROUND: Cryptosporidiosis is a zoonotic intestinal infectious disease caused by Cryptosporidium spp., and its transmission is highly influenced by climate factors. In the present study, the potential spatial distribution of Cryptosporidium in China was predicted based on ecological niche models for cryptosporidiosis epidemic risk warning and prevention and control. METHODS: The applicability of existing Cryptosporidium presence points in ENM analysis was investigated based on data from monitoring sites in 2011-2019. Cryptosporidium occurrence data for China and neighboring countries were extracted and used to construct the ENMs, namely Maxent, Bioclim, Domain, and Garp. Models were evaluated based on Receiver Operating Characteristic curve, Kappa, and True Skill Statistic coefficients. The best model was constructed using Cryptosporidium data and climate variables during 1986‒2010, and used to analyze the effects of climate factors on Cryptosporidium distribution. The climate variables for the period 2011‒2100 were projected to the simulation results to predict the ecological adaptability and potential distribution of Cryptosporidium in future in China. RESULTS: The Maxent model (AUC = 0.95, maximum Kappa = 0.91, maximum TSS = 1.00) fit better than the other three models and was thus considered the best ENM for predicting Cryptosporidium habitat suitability. The major suitable habitats for human-derived Cryptosporidium in China were located in some high-population density areas, especially in the middle and lower reaches of the Yangtze River, the lower reaches of the Yellow River, and the Huai and the Pearl River Basins (cloglog value of habitat suitability > 0.9). Under future climate change, non-suitable habitats for Cryptosporidium will shrink, while highly suitable habitats will expand significantly (χ2 = 76.641, P < 0.01; χ2 = 86.836, P < 0.01), and the main changes will likely be concentrated in the northeastern, southwestern, and northwestern regions. CONCLUSIONS: The Maxent model is applicable in prediction of Cryptosporidium habitat suitability and can achieve excellent simulation results. These results suggest a current high risk of transmission and significant pressure for cryptosporidiosis prevention and control in China. Against a future climate change background, Cryptosporidium may gain more suitable habitats within China. Constructing a national surveillance network could facilitate further elucidation of the epidemiological trends and transmission patterns of cryptosporidiosis, and mitigate the associated epidemic and outbreak risks.


Asunto(s)
Criptosporidiosis , Cryptosporidium , Humanos , Cambio Climático , Ecosistema , Brotes de Enfermedades , China
4.
Sci Rep ; 12(1): 17239, 2022 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-36241909

RESUMEN

Rodents are natural reservoirs of diverse zoonotic viruses and widely distributed on the Tibetan Plateau. A comprehensive understanding of the virome in local rodent species could provide baseline of viral content and assist in efforts to reduce the risk for future emergence of rodent related zoonotic diseases. A total of 205 tissue and fecal samples from 41 wild Qinghai voles were collected. Metagenomic analyses were performed to outline the characteristics of the viromes, and phylogenetic analyses were used to identify the novel viral genomes. The virome distribution among five tissues (liver, lung, spleen, small intestine with content and feces) was also compared. We identified sequences related to 46 viral families. Novel viral genomes from distinct evolutionary lineages with known viruses were characterized for their genomic and evolutionary characteristics, including Hepatovirus, Hepacivirus, Rotavirus, and Picobirnavirus. Further analyses revealed that the core virome harbored by rodent internal tissues were quite different from the virome found in intestine and fecal samples. These findings provide an overview of the viromes in wild Qinghai voles, which are unique and the most common rodent species in the eastern Tibetan Plateau. A high diversity of viruses is likely present in rodent species in this area.


Asunto(s)
Viroma , Virus , Animales , Arvicolinae/genética , Heces , Metagenómica , Filogenia , Roedores/genética , Tibet , Virus/genética
5.
Infect Dis Poverty ; 10(1): 130, 2021 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-34742346

RESUMEN

BACKGROUND: Cystic echinococcosis (CE), caused by the larval stage of the complex Echinococcus granulosus sensu lato (s.l.), is a zoonotic parasitic disease with a high social burden in China. E. ortleppi is a species (formerly genotype 5 of E. granulosus s.l.) with unique epidemic areas (tropical areas), transmission patterns (mainly cattle origin), and pathological characteristics (large and small hook lengths) compared to other species that cause CE. A 19-year-old female patient in an area with no history of echinococcosis in Guizhou Province, China, was diagnosed with E. ortleppi infection in 2019. This study is to understand the source of this human E. ortleppi infection. METHODS: We performed computer tomography (CT) scans, surgical operation, morphological sectioning, molecular diagnosis, phylogenetic analyses, and epidemiological investigation in Anshun City, Guizhou Province, China in 2019. RESULTS: The patient presented with intermittent distension and pain in the upper abdomen without other abnormal symptoms. Routine blood examination results were normal. However, abdominal CT revealed a fertile cyst with a diameter of approximately 8 cm, uniform density, and a clear boundary, but without an evident cyst wall in the right lobe of the liver. The cyst was fertile, and phylogenetic analyses revealed that the isolates represented a new E. ortleppi genus haplotype. A result of 10‒14 years incubation period with indigenous infection was considered available for the case through the epidemiological survey. CONCLUSIONS: CE due to E. ortleppi infection can be confused with other diseases causing liver cysts, resulting in misdiagnosis. A transmission chain of E. ortleppi may exist or existed in the past in the previously considered non-endemic areas of echinococcosis in southwestern China.


Asunto(s)
Equinococosis , Echinococcus , Animales , China/epidemiología , Equinococosis/diagnóstico , Equinococosis/epidemiología , Echinococcus/genética , Echinococcus/patogenicidad , Femenino , Genotipo , Humanos , Filogenia , Adulto Joven
7.
Evol Appl ; 14(1): 117-135, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33519960

RESUMEN

Understanding the mechanisms of how urbanization influences the evolution of native species is vital for urban wildlife ecology and conservation in the Anthropocene. With thousands of years of agriculture-dominated historical urbanization followed by 40 years of intensive and rapid urbanization, Shanghai provides an ideal environment to study how the two-stage urbanization process influences the evolution of indigenous wildlife, especially of anuran species. Therefore, in this study, we used mitochondrial Cyt-b gene, microsatellite (SSR), and single nucleotide polymorphism (SNP) data to evaluate the demographic history and genetic structure of the eastern golden frog (Pelophylax plancyi), by sampling 407 individuals from 15 local populations across Shanghai, China. All local populations experienced bottlenecks during historical urbanization, while the local populations in urban areas maintained comparable contemporary effective population sizes (N e) and genetic diversity with suburban and rural populations. Nevertheless, the rapid modern urbanization has already imposed significant negative effects to the integrity of populations. The 15 local populations were differentiated into eight genetic clusters, showing a spatial distribution pattern consistent with the current urbanization gradient and island-mainland geography. Although moderate gene flow still occurred from the rural peripheral cluster to urban and suburban clusters, population fragmentation was more serious in the urban and suburban populations, where higher urbanization levels within 2-km radius areas showed significant negative relationships to the N e and genetic diversity of local populations. Therefore, to protect urban wildlife with limited dispersal ability, improving conditions in fragmented habitat remnants might be most essential for local populations living in more urbanized areas. Meanwhile, we highlight the need to preserve large unfragmented rural habitats and to construct corridor networks to connect discrete urban habitat remnants for the long-term wildlife conservation in intensively urbanizing environments.

8.
Ecol Evol ; 10(17): 9567-9580, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32953084

RESUMEN

Wind farms offer a cleaner alternative to fossil fuels and can mitigate their negative effects on climate change. However, wind farms may have negative impacts on birds. The East China Coast forms a key part of the East Asian-Australasian Flyway, and it is a crucial region for wind energy development in China. However, despite ducks being the dominant animal taxon along the East China Coast in winter and considered as particularly vulnerable to the effects of wind farms, the potential negative impacts of wind farms on duck populations remain unclear. We therefore assessed the effects of wind farms on duck abundance, distribution, and habitat use at Chongming Dongtan, which is a major wintering site for ducks along the East Asian-Australasian Flyway, using field surveys and satellite tracking. We conducted seven paired field surveys of ducks inside wind farm (IWF) and outside wind farm (OWF) sites in artificial brackish marsh, paddy fields, and aquaculture ponds. Duck abundance was significantly higher in OWF compared with IWF sites and significantly higher in artificial brackish marsh than in aquaculture ponds and paddy fields. Based on 1,918 high-resolution satellite tracking records, the main habitat types of ducks during the day and at night were artificial brackish marsh and paddy fields, respectively. Furthermore, grid-based analysis showed overlaps between ducks and wind farms, with greater overlap at night than during the day. According to resource selection functions, habitat use by wintering ducks was impacted by distance to water, land cover, human activity, and wind farm effects, and the variables predicted to have significant impacts on duck habitat use differed between day and night. Our study suggests that wintering ducks tend to avoid wind turbines at Chongming Dongtan, and landscape of paddy fields and artificial wetlands adjoining natural wetlands is crucial for wintering ducks.

9.
Parasit Vectors ; 13(1): 207, 2020 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32317015

RESUMEN

BACKGROUND: The pastoral area of the eastern Tibetan Plateau is highly endemic for human echinococcosis. Domestic dogs are the main definitive host for the transmission of both Echinococcus granulosus (sensu lato) and E. multilocularis to humans. To control the infection risks, a national-level canine echinococcosis prevention and control programme has been implemented since 2015 in Shiqu County, Ganze Tibetan Autonomous Prefecture, Sichuan, China. The objective of this study was to evaluate its effect on Echinococcus spp. prevalence in dogs. METHODS: We surveyed 69 households with 84 owned dogs, for dog fecal samples and dog keeping information in the villages of Rizha and Eduoma. A total of 105 dog fecal samples (75 from owned dogs and 30 unknown dog fecal samples) were collected between 2015-2017 to determine Echinococcus spp. prevalence using copro-PCR. Eight variables based on household surveys were included into a logistic regression model for significant risk factors to canine echinococcosis prevalence in dogs. RESULTS: Between 2015-2017, the overall Echinococcus spp. copro-DNA prevalence decreased significantly in dogs from 51.2% (2015) to 20.0% (2017) in Rizha, and insignificantly from 11.5% (2016) to 4.3% (2017) in Eduoma. Echinococcus multilocularis was the most prevalent species continually copro-DNA detected during the entire study period, while E. granulosus was rare and not detected in 2017. Echinococcus shiquicus copro-DNA prevalence (a probable non-zoonotic wildlife species) was as high in dogs as that of E. multilocularis, although only detected in 2015 in Rizha. Unleashed dog feces were mainly collected in Rizha in 2015. Although 93.2% of owned dogs were leashed, and the monthly praziquantel dosing rate reached 97%, E. multilocularis infection could still be detected in 11.1% of owned dogs in 2017. Monthly deworming, leashing dogs 24 h per day, and the avoidance of dogs feeding on livestock viscera were significant measures to prevent canine echinococcosis infection in owned dogs. CONCLUSIONS: Carrying out a canine echinococcosis prevention and control programme can significantly decrease Echinococcus spp. prevalence. The potential contact between leashed dogs and wild small mammals is still a risk for re-infection of owned dogs with E. multilocularis. This study shows that the long-term application of regular dog treatment with praziquantel in the vast and remote echinococcosis endemic areas of the eastern Tibetan Plateau can reduce transmission in dogs but remains a challenging intervention.


Asunto(s)
Enfermedades de los Perros/prevención & control , Equinococosis/prevención & control , Equinococosis/veterinaria , Heces/parasitología , Mascotas/parasitología , Animales , China/epidemiología , Control de Enfermedades Transmisibles , Enfermedades de los Perros/parasitología , Perros/parasitología , Equinococosis/epidemiología , Echinococcus granulosus/aislamiento & purificación , Echinococcus multilocularis/aislamiento & purificación , Enfermedades Endémicas/prevención & control , Composición Familiar , Femenino , Humanos , Masculino , Prevalencia , Factores de Riesgo , Población Rural/estadística & datos numéricos , Encuestas y Cuestionarios , Tibet/epidemiología
10.
Curr Zool ; 66(6): 615-623, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33391360

RESUMEN

Amphibians play a key role in structuring biological assemblages of agricultural landscapes, but they are threatened by global agricultural intensification. Landscape structure is an important variable influencing biodiversity in agricultural landscapes. However, in the Yangtze River Delta, where a "farmland-orchard-fishpond" agricultural pattern is common, the effects of landscape construction on anuran populations are unclear. In this study, we examined the effects of agricultural landscape parameters on the abundance and body condition of the rice frog (Fejervarya multistriata), which is a dominant anuran species in farmland in China. Employing a visual encounter method, we surveyed rice frog abundance for 3 years across 20 agricultural landscapes. We also calculated the body condition index (BCI) of 188 male frog individuals from these agricultural landscapes. Landscape variables, comprising landscape compositional heterogeneity (using the Shannon diversity index of all land cover types except buildings and roads), landscape configurational heterogeneity (using landscape edge density), breeding habitat diversity (using the number of 5 waterbody types available as breeding habitats), and areas of forest were also measured for each 1-km radius landscape. We found that the amount of forest in each agricultural landscape had a significant positive relationship with rice frog abundance, and breeding habitat diversity was positively related to the BCI of male rice frogs. However, body condition was negatively impacted by landscape configurational heterogeneity. Our results suggested the importance of nonagricultural habitats in agricultural landscapes, such as waterbodies and forest, to benefit rice frog population persistence.

11.
Integr Zool ; 15(3): 202-212, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31773863

RESUMEN

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.


Asunto(s)
Repeticiones de Microsatélite , Rumiantes/clasificación , Animales , China , Variación Genética , Mitocondrias/genética , Filogenia , Rumiantes/genética , Análisis de Secuencia de ADN/veterinaria , Ovinos/clasificación , Ovinos/genética
12.
Sensors (Basel) ; 19(3)2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30678172

RESUMEN

Radio tomographic imaging (RTI) has emerged as a promising device-free localization technology for locating the targets with no devices attached. RTI deduces the location information from the reconstructed attenuation image characterizing target-induced spatial loss of radio frequency measurements in the sensing area. In cluttered indoor environments, RF measurements of wireless links are corrupted by multipath effects and thus less robust to achieve a high localization accuracy for RTI. This paper proposes to improve the quality of measurements by using spatial diversity. The key insight is that, with multiple antennae equipped, due to small-scale multipath fading, RF measurement variation of each antenna pair behaves differently. Therefore, spatial diversity can provide more reliable and strong measurements in terms of link quality. Moreover, to estimate the location from the image more precisely and make the image more identifiable, we propose using a new reconstruction regularization linearly combining the sparsity and correlation inherent in the image. The proposed reconstruction method can remarkably reduce the image noise and enhance the imaging accuracy especially in the case of a few available measurements. Indoor experimental results demonstrate that compared to existing RTI improvement methods, our RTI solution can reduce the root-mean-square localization error at least 47% while also improving the imaging performance.

13.
Parasit Vectors ; 11(1): 302, 2018 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-29769131

RESUMEN

BACKGROUND: The eastern part of the Tibetan Plateau is now recognized as an endemic region with the highest reported human infection rates in the world of human alveolar echinococcosis (AE) caused by Echinococcus multilocularis. Existing epidemiological studies on AE have mainly focused on the synanthropic environment, while basic parasitological and ecological aspects in wildlife host species remain largely unknown, especially for small mammal hosts. Therefore, we examined small mammal host species composition, occurrence, and the prevalence of both E. multilocularis and E. shiquicus in Shiqu County (Sichuan Province, China), eastern Tibetan Plateau. RESULTS: In total, 346 small mammals from five rodent and one pika species were trapped from four randomly set 0.25 ha square plots. Two vole species, Lasiopodomys fuscus (n = 144) and Microtus limnophilus (n = 44), and the plateau pika (Ochotona curzoniae) (n = 135), were the three most-dominant species trapped. Although protoscoleces of E. multilocularis and E. shiquicus were only observed in L. fuscus and O. curzoniae, respectively, cox1 and nad1 gene DNA of E. shiquicus was detected in all the small mammal species except for Neodon irene, whereas E. multilocularis was detected in the three most-dominant species. The overall molecular prevalence of Echinococcus species was 5.8 (95% CI: 3.3-8.2%) ~ 10.7% (95% CI: 7.4-14.0%) (the conservative prevalence to the maximum prevalence with 95% CI in parentheses), whereas for E. multilocularis it was 4.3 (95% CI: 2.2-6.5%) ~ 6.7% (95% CI: 4.0-9.3%), and 1.5 (95% CI: 0.2-2.7%) ~ 4.1% (95% CI: 2.0-6.1%) for E. shiquicus. The prevalence of both E. multilocularis and E. shiquicus, was significantly higher in rodents (mainly voles) than in pikas. Phylogenetic analyses revealed that Echinococcus haplotypes of cox1 from small mammal hosts were actively involved in the sylvatic and anthropogenic transmission cycles of E. multilocularis in the eastern Tibetan Plateau. CONCLUSIONS: In contrast to previous studies, the current results indicated that rodent species, rather than pikas, are probably more important natural intermediate hosts of E. multilocularis and E. shiquicus in the eastern Tibetan Plateau. Thus, understanding interspecific dynamics between rodents and pikas is essential to studies of the echinococcosis transmission mechanism and human echinococcosis prevention in local communities.


Asunto(s)
Equinococosis/veterinaria , Echinococcus multilocularis/aislamiento & purificación , Echinococcus/genética , Mamíferos/parasitología , Animales , China/epidemiología , ADN de Helmintos/genética , Equinococosis/epidemiología , Equinococosis/parasitología , Equinococosis/transmisión , Echinococcus/clasificación , Echinococcus/aislamiento & purificación , Echinococcus multilocularis/genética , Zorros/parasitología , Haplotipos , Especificidad del Huésped , Humanos , Lagomorpha/parasitología , Filogenia , Prevalencia , Roedores/parasitología , Tibet/epidemiología
14.
Vet Microbiol ; 208: 53-57, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28888649

RESUMEN

The H5N6 avian influenza virus (AIV) has been continuously reported in wild birds, which may contribute to further geographical spread during their long-distance migrations. Active AIV surveillance in wild birds was conducted during October and November 2016 in Shanghai, China. Two novel influenza A (H5N6) viruses were detected in samples from migratory waterfowl that are genetically similar to recent South Korea and Japan H5N6 viruses collected in 2016 and 2017, highlighting the role of migratory waterfowl in the dissemination of H5N6 viruses along migratory flyways.


Asunto(s)
Animales Salvajes , Anseriformes/virología , Virus de la Influenza A/clasificación , Gripe Aviar/virología , Animales , China/epidemiología , Genotipo , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Filogenia
15.
Sensors (Basel) ; 17(5)2017 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-28448464

RESUMEN

Received-signal-strength-based (RSS-based) device-free localization (DFL) is a promising technique since it is able to localize the person without attaching any electronic device. This technology requires measuring the RSS of all links in the network constituted by several radio frequency (RF) sensors. It is an energy-intensive task, especially when the RF sensors work in traditional work mode, in which the sensors directly send raw RSS measurements of all links to a base station (BS). The traditional work mode is unfavorable for the power constrained RF sensors because the amount of data delivery increases dramatically as the number of sensors grows. In this paper, we propose a binary work mode in which RF sensors send the link states instead of raw RSS measurements to the BS, which remarkably reduces the amount of data delivery. Moreover, we develop two localization methods for the binary work mode which corresponds to stationary and moving target, respectively. The first localization method is formulated based on grid-based maximum likelihood (GML), which is able to achieve global optimum with low online computational complexity. The second localization method, however, uses particle filter (PF) to track the target when constant snapshots of link stats are available. Real experiments in two different kinds of environments were conducted to evaluate the proposed methods. Experimental results show that the localization and tracking performance under the binary work mode is comparable to the those in traditional work mode while the energy efficiency improves considerably.

17.
Dongwuxue Yanjiu ; 35(6): 528-36, 2014 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-25465089

RESUMEN

Cervus sichuanicus is a species of sika deer (Cervus nippon Group). To date, research has mainly focused on quantity surveying and behavior studies, with genetic information on this species currently deficient. To provide scientific evidence to assist in the protection of this species, we collected Sichuan sika deer fecal samples from the Sichuan Tiebu Nature Reserve (TNR) and extracted DNA from those samples. Microsatellite loci of bovine were used for PCR amplification. After GeneScan, the genotype data were used to analyze the genetic diversity and population structure of the Sichuan sika deer in TNR. Results showed that the average expected heterozygosity of the Sichuan sika deer population in TNR was 0.562, equivalent to the average expected heterozygosity of endangered animals, such as Procapra przewalskii. Furthermore, 8 of 9 microsatellite loci significantly deviated from the Hardy-Weinberg equilibrium and two groups existed within the Sichuan sika deer TNR population. This genetic structure may be caused by a group of Manchurian sika deer (Cervus hortulorum) released in TNR.


Asunto(s)
Ciervos/genética , Variación Genética , Repeticiones de Microsatélite/genética , Animales , China
18.
Mol Ecol ; 23(19): 4813-30, 2014 10.
Artículo en Inglés | MEDLINE | ID: mdl-25212210

RESUMEN

Widely distributed taxa provide an opportunity to compare biogeographic responses to climatic fluctuations on multiple continents and to investigate speciation. We conducted the most geographically and genomically comprehensive study to date of the red fox (Vulpes vulpes), the world's most widely distributed wild terrestrial carnivore. Analyses of 697 bp of mitochondrial sequence in ~1000 individuals suggested an ancient Middle Eastern origin for all extant red foxes and a 400 kya (SD = 139 kya) origin of the primary North American (Nearctic) clade. Demographic analyses indicated a major expansion in Eurasia during the last glaciation (~50 kya), coinciding with a previously described secondary transfer of a single matriline (Holarctic) to North America. In contrast, North American matrilines (including the transferred portion of Holarctic clade) exhibited no signatures of expansion until the end of the Pleistocene (~12 kya). Analyses of 11 autosomal loci from a subset of foxes supported the colonization time frame suggested by mtDNA (and the fossil record) but, in contrast, reflected no detectable secondary transfer, resulting in the most fundamental genomic division of red foxes at the Bering Strait. Endemic continental Y-chromosome clades further supported this pattern. Thus, intercontinental genomic exchange was overall very limited, consistent with long-term reproductive isolation since the initial colonization of North America. Based on continental divergence times in other carnivoran species pairs, our findings support a model of peripatric speciation and are consistent with the previous classification of the North American red fox as a distinct species, V. fulva.


Asunto(s)
Evolución Molecular , Zorros/genética , Genética de Población , Filogenia , Alelos , Animales , Teorema de Bayes , Núcleo Celular/genética , Análisis por Conglomerados , ADN Mitocondrial/genética , Flujo Génico , Marcadores Genéticos , Variación Genética , Medio Oriente , Modelos Genéticos , América del Norte , Filogeografía , Análisis de Secuencia de ADN
19.
J Parasitol ; 100(4): 542-6, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24611571

RESUMEN

The family Taeniidae comprises many parasitic species, which cause serious zoonoses. However, effective identification of Taeniidae species is a long-standing problem, especially in samples from wild hosts with mixed infections of different Taeniidae species. DNA barcoding analysis of small fragments of the cytochrome c oxidase subunit I (COI) gene has been confirmed as an effective and useful method for identifying Taenia species. We therefore performed DNA barcoding analysis using a 351-bp region of the COI gene to identify 27 taeniid species including 9 in the genus Echinococcus, 2 in Hydatigera, 15 in Taenia, and 1 in Versteria. A total of 484 COI sequences were used to calculate genetic divergence expressed by the Kimura 2-parameter (K2P) distance. The mean intra-specific K2P distance in the family Taeniidae was 0.71 ± 0.17% (±SE), while inter-specific divergences were considerably higher. We found that, generally, a 2.0% optimal barcoding threshold could be set to distinguish taeniid species. Taenia polyacantha and Hydatigera taeniaeformis were the only 2 false-positive species identification cases in this study for their intra-specific divergences above the 2.0% optimal threshold. Their high intra-specific divergences coincided with fact that cryptic divergences exist in these 2 species, to which new taxa were recommended. On the other hand, sister species T. asiatica and T. saginata showed a 2.48 ± 0.83% inter-specific divergence, which was the smallest among all the taeniid species. Although fitting the 2.0% optimal species barcoding threshold, the close genetic relationship between T. asiatica and T. saginata implies that longer mitochondrial DNA sequences like the complete COI sequence are needed to strictly distinguish them. Therefore, we concluded that the barcoding technique based on a 351-bp region of the COI gene is able to distinguish taeniid species except for cryptic T. polyacantha and H. taeniaeformis and should be carefully used in distinguishing the closely related species T. asiatica and T. saginata .


Asunto(s)
Cestodos/clasificación , Código de Barras del ADN Taxonómico/normas , Animales , Cestodos/genética , Cestodos/aislamiento & purificación , Código de Barras del ADN Taxonómico/métodos , Complejo IV de Transporte de Electrones/genética , Haplotipos
20.
Curr Pharm Des ; 20(33): 5348-53, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24479798

RESUMEN

BACKGROUND: Although genistein has been reported to exert its anti-tumor activity, the exact mechanism of its action is poorly elucidated. Recently, it has been found that genistein could regulate the expression of microRNAs. Therefore, our aim in the present study was to find whether genistein regulates specific miR-27a in pancreatic cancer cells. METHODS: We performed our studies using multiple methods including MTT assay, RT-PCR, Western blotting analysis, migration, invasion assay, and transfection. RESULTS: We observed that genistein significantly inhibited the expression of miR-27a in pancreatic cancer cells. Moreover, inhibition of miR-27a suppressed cell growth and induced apoptosis as well as inhibited invasion in pancreatic cancer cells. Furthermore, we found a synergy effect between miR-27a and genistein on cell growth inhibition, apoptosis, and invasion, suggesting that targeting miR-27a may represent a potential strategy for treatment of pancreatic cancer. CONCLUSIONS: Our findings demonstrated that genistein plays a tumor suppressor role in part through inhibition of miR-27a in pancreatic cancer cells.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Genisteína/farmacología , MicroARNs/antagonistas & inhibidores , Invasividad Neoplásica/prevención & control , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Genisteína/química , Genisteína/uso terapéutico , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Relación Estructura-Actividad , Células Tumorales Cultivadas
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