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1.
Environ Pollut ; 262: 114366, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32443214

RESUMO

Ground-level ozone pollution has negative impacts on human health and vegetation and has increased rapidly across China. Various factors are implicated in the formation of ozone (e.g., meteorological factors, anthropogenic emissions), but their relative individual impact and the impact of interactions between these factors remains unclear. This study quantified the influence of specific meteorological conditions and anthropogenic precursor emissions and their interactions on ozone concentrations in Chinese cities using the geographic detector model (GeoDetector). Results revealed that the impacts of meteorological and anthropogenic factors and their interactions on ozone concentrations varied significantly at different spatial and temporal scales. Temperature was the dominant driver at the annual time scale, explaining 40% (q = 0.4) of the ground-level ozone concentration. Anthropogenic precursors and meteorological conditions had comparable effects on ozone concentrations in summer and winter in northern China. Interactions between all the factors can enhance effects. The interaction between meteorological factors and anthropogenic precursors had the strongest impact in summer. The results can be used to enhance our understanding of ozone pollution, to improve ozone prediction models, and to formulate pollution control measures.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31968158

RESUMO

Vanadium dioxide (VO2)-based thermochromic coatings has attracted considerable attention in the application of smart windows as a result of their intriguing property of metal-insulator transition at moderate temperatures. However, the practical requirements of smart windows, i.e., the high luminous transmittance of Tlum > 60% and large solar modulating ability of ΔTsol > 10%, are competing to a large extent and hardly satisfied simultaneously. Here, we proposed a facile and universal method to prepare VO2 coatings for exceeding the criteria above using double-sided localized surface plasmon resonances (LSPRs), which are excited by the VO2 nanoparticles dispersed evenly on both surfaces of the fused silica substrate. With subtle engineering of the sol-gel and heat treatment processes, the morphology of as-prepared VO2 nanoparticles and corresponding LSPRs are controlled to achieve a high luminous transmittance (Tlum = 68.2%) and solar modulating ability (ΔTsol = 11.7%) simultaneously. Further simulation suggests that the double-sided LSPRs can collectively enhance the performance of VO2 smart coatings. Moreover, the double-sided VO2 nanoparticle coatings demonstrate stable performance with no more than 1% degradation of Tlum and ΔTsol after 1500 cycles. This study provides an alternative strategy to obtain high-quality VO2 (M) solar modulating coatings.

3.
Sci Total Environ ; 699: 134367, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31677474

RESUMO

Accurate quantification of the terrestrial water balance can improve our knowledge of regional water cycle changes, and deepen our understanding of evaporation in hydrological cycle and under climate change. However, sparse observation networks on the Tibetan Plateau (TP) prevent the reliable estimates of actual evaporation. Based on the China regional surface Meteorological Feature Dataset (CMFD) and the Global Land Surface Satellite (GLASS) product, we adopted the latest rescaled nonlinear complementary relationship (CR) to calculate the monthly actual evaporation (E) from 1982 to 2015. We analyzed the spatio-temporal variability of the annual E on the entire TP, and explored the main meteorological factors controlling the annual E and the regulation of multiyear average annual E in different vegetation zones from southeast to northwest. Our results indicated that the net radiation (Rn) and E exhibited a favorable agreement with monthly changes of the observed values; and E estimated by the CR explained 79-96% variation of the eddy covariance flux measurements. The multiyear average E was 373.12 mm yr-1 and displayed similar spatial patterns of decreasing from southeast to northwest with two remote sensing products (GLDAS_VIC, GLEAM_v3.3) and one hydrological model (Budyko). Additionally, based on the Mann-Kendall trend test, there were 21.56% of the TP with significant upward trend of annual E which mainly distributed in the area with dense glaciers. The Nyenchen Tanglha Mountains and Pamirs Plateau area had the most obvious upward trend, with up to over 6 mm yr-1. In a relative sense, the key meteorological elements which affected annual E on the TP were relative humidity (RH) (r = 0.63) and Rn (r = 0.56).

4.
Sensors (Basel) ; 19(24)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842440

RESUMO

: For a diesel engine, operating conditions have extreme importance in fault detection and diagnosis. Limited to various special circumstances, the multi-factor operating conditions of a diesel engine are difficult to measure, and the demand of automatic condition recognition based on vibration signals is urgent. In this paper, multi-factor operating condition recognition using a one-dimensional (1D) convolutional long short-term network (1D-CLSTM) is proposed. Firstly, a deep neural network framework is proposed based on a 1D convolutional neural network (CNN) and long short-Term network (LSTM). According to the characteristics of vibration signals of a diesel engine, batch normalization is introduced to regulate the input of each convolutional layer by fixing the mean value and variance. Subsequently, adaptive dropout is proposed to improve the model sparsity and prevent overfitting in model training. Moreover, the vibration signals measured under 12 operating conditions were used to verify the performance of the trained 1D-CLSTM classifier. Lastly, the vibration signals measured from another kind of diesel engine were applied to verify the generalizability of the proposed approach. Experimental results show that the proposed method is an effective approach for multi-factor operating condition recognition. In addition, the adaptive dropout can achieve better training performance than the constant dropout ratio. Compared with some state-of-the-art methods, the trained 1D-CLSTM classifier can predict new data with higher generalization accuracy.

5.
Sensors (Basel) ; 19(11)2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174383

RESUMO

The diesel engine has been a significant component of large-scale mechanical systems for the intelligent manufacturing industry. Because of its complex structure and poor working environment, it has trouble effectively acquiring the representative fault features. Further, fault diagnosis of the diesel engine faces great challenges. This paper presents a new fault diagnosis method for the detection of diesel engine faults under multiple operation conditions instead of conventional methods confined to a single condition. First, an adaptive correlation threshold process is designed as a preprocessing unit to enhance data quality by weakening non-impact region characteristics. Next, a feature extraction method for sound signals based on the Mel frequency cepstrum (MFC) is improved and introduced into the machinery fault diagnosis. Then, the combination of the improved feature and vibrational mode decomposition (VMD) is proposed to incorporate VMD into an effective adaptive decomposition of non-stationary signals to combine it with an excellent feature representation of the vibration signal. Finally, the vector quantization algorithm is adopted to reduce the feature dimensions and generate codebook model bases, which trains the K-Nearest Neighbor classifiers. Five comparative methods were carried out, and the experimental results show that the proposed method offers a good effect of the common valve clearance fault of diesel engines under different conditions.

6.
Sci Total Environ ; 687: 257-266, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207515

RESUMO

Potential evapotranspiration (ET0) is one of the important indicators for characterizing atmospheric evapotranspiration, but arduous observation conditions lead to a relative lack in the understanding of the ET0 mechanism in cold, high-elevation regions. The study of the sensitivity coefficient and contribution rate of meteorological elements to ET0 under the effects of the freeze-thaw cycle in the permafrost regions of the Qinghai-Tibet Plateau (QTP) showed that air temperature (T) and ET0 had similar change trends, which reached a peak during the summer thawing period (ST). Furthermore, analysis of meteorological elements in different freeze-thaw stages of the active layer soil revealed that the contribution rate of each meteorological element to ET0 showed a seasonal distinction. The sensitivity coefficient and contribution rate of the net radiation (Rn) and vapor pressure deficit (VPD) to ET0 were high, and their mean values were 0.52 and 0.44, respectively. In contrast, the sensitivity coefficient and contribution rate of wind speed (u2) and T to ET0 were very small, and the mean values of the sensitivity coefficient were 0.08 and 0.01, respectively. Additionally, T had the lowest contribution rate to ET0. These results indicated that permafrost had a stable regulatory effect on T. The results are expected to be helpful in developing a process-based frozen soil hydrological model.

7.
Beilstein J Nanotechnol ; 10: 848-855, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019872

RESUMO

MnO2-CuO-Fe2O3/CNTs catalysts, as a low-dimensional material, were fabricated by a mild redox strategy and used in denitration reactions. A formation mechanism of the catalysts was proposed. NO conversions of 4% MnO2-CuO-Fe2O3/CNTs catalyst of 43.1-87.9% at 80-180 °C were achieved, which was ascribed to the generation of amorphous MnO2, CuO and Fe2O3, and a high surface-oxygen (Os) content.

8.
Environ Pollut ; 246: 11-18, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30529935

RESUMO

As the second largest economy in the world, China experiences severe particulate matter (PM) pollution in many of its cities. Meteorological factors are critical in determining both areal and temporal variations in PM pollution levels; understanding these factors and their interactions is critical for accurate forecasting, comprehensive analysis, and effective reduction of this pollution. This study analyzed areal and temporal variations in concentrations of PM2.5, PM10, and PMcoarse (PM10 - PM2.5) and PM2.5 to PM10 ratios (PM2.5/PM10) and their relationships with meteorological conditions in 366 Chinese cities from January 1, 2015 to December 31, 2017. On the national scale, PM2.5 and PM10 decreased from 48 to 42 µg m-³ and from 88 to 84 µg m-³, respectively, and the annual mean concentrations were 45 µg m-³ (PM2.5) and 84 µg m-³ (PM10) during the time period (2015-2017). In most regions, largest PM concentrations occurred in winter. However, in northern China, in spring PMcoarse concentrations were highest due to dust. The PM2.5/PM10 ratio was higher in southern than in northern China. There were large regional disparities in PM diurnal variations. Generally, PM concentrations were negatively correlated with precipitation, relative humidity, air temperature, and wind speed, but were positively correlated with surface pressure. The sunshine duration showed negative and positive impacts on PM in northern and southern cities, respectively. Meteorological factors impacted particulates of different size differently in different regions and over different periods of time.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/estatística & dados numéricos , Conceitos Meteorológicos , Material Particulado/análise , China , Cidades , Poeira/análise , Tamanho da Partícula , Estações do Ano
9.
Sensors (Basel) ; 20(1)2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31906062

RESUMO

Diesel engine fault diagnosis is vital due to enhanced reliability and economic efficiency requirements. The extracted features in traditional fault diagnosis are constructed manually, which is very cumbersome because of the requirement for lots of expertise. To handle this issue, this paper proposed a variational stacked autoencoder (VSAE) to adaptively extract features from angular domain signals. As an unsupervised algorithm, VSAE can extract high-level features with the help of multiple encoding layers. Layer-wise pre-training and fine-tuning are introduced to get a better network initialization value. Moreover, the dropout technique and the batch normalization technique are carried out to prevent over-fitting and implement fast convergence. Finally, the harmony search optimizer (HSO) algorithm is introduced to get an appropriate hyper-parameter setting in the VSAE model, as well as make adaptive adjustment of the network structure. In order to verify the proposed method, the valve train fault data is collected on the diesel engine test rig under twelve operating conditions. The results indicate that the proposed scheme can effectively diagnose different degrees of intake valve fault, exhaust valve fault, and coupling fault under various operating conditions. Furthermore, the classification accuracy improved from 94.10% to 98.85%VSAE compared with stacked autoencoder (SAE) and some other traditional fault diagnosis algorithms.

10.
Curr Biol ; 28(10): R590-R592, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29787716

RESUMO

Overexploitation, habitat destruction, human-driven climate change and disease spread are resulting in the extinction of innumerable species, with amphibians being hit harder than most other groups [1]. Few species of amphibians are widespread, and those that are often represent complexes of multiple cryptic species. This is especially true for range-restricted salamanders [2]. Here, we used the widespread and critically endangered Chinese giant salamander (Andrias davidianus) to show how genetically uninformed management efforts can negatively affect species conservation. We find that this salamander consists of at least five species-level lineages. However, the extensive recent translocation of individuals between farms, where the vast majority of extant salamanders now live, has resulted in genetic homogenization. Mitochondrial DNA (mtDNA) haplotypes from northern China now predominate in farms. Unfortunately, hybrid offspring are being released back into the wild under well-intentioned, but misguided, conservation management. Our findings emphasize the necessity of genetic assessments for seemingly well-known, widespread species in conservation initiatives. Species serve as the primary unit for protection and management in conservation actions [3], so determining the taxonomic status of threatened species is a major concern, especially for amphibians. The level of threat to amphibians may be underestimated, and existing conservation strategies may be inadvertently harmful if conducted without genetic assessment.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Variação Genética , Hibridização Genética , Urodelos , Animais , Ecossistema , Genética Populacional , Urodelos/classificação , Urodelos/genética
11.
Zookeys ; (694): 95-108, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29134001

RESUMO

A new species of brown frog Rana luanchuanensis Zhao & Yuan, sp. n. is described from Luanchuan County, western Henan, central China. The mitochondrial genealogy suggests that the new species is the sister taxon to the clade including R. amurensis and R. coreana, and is separated by uncorrected pairwise distances more than 12.5%. Morphologically, this new species differs from its congeners by a suite of characters. Analyses of partial sequences of cytochrome oxidase subunit I (COI) resolve the new species as a single matriline.

12.
Sci Rep ; 7(1): 13381, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29042590

RESUMO

Bradysia odoriphaga and Bradysia difformis are devastating pests of vegetable, ornamental crops and edible mushrooms causing significant losses. Temperature may be an important factor restricting their population abundance in the summer. To determine the effects of short-term heat shock on adults, their survival, longevity and fecundity data were collected, and antioxidant responses and heat shock protein expression levels were examined. Our results indicated that the survival rates of Bradysia adults decreased rapidly after heat shock ≥36 °C, and the longevity and reproductive capacities were significantly inhibited, indicating that short-term heat shock had lethal and sub-lethal effects. Moreover, the lipid peroxidation levels of B. difformis and B. odoriphaga increased dramatically at 36 °C and 38 °C, respectively. Four antioxidant enzymes activities of B. odoriphaga were greater than those of B. difformis at 38 °C. Additionally, hsp70 and hsp90 expression levels significantly increased after heat stress, and higher expression levels of B. difformis and B. odoriphaga were discovered at 36 and 38 °C respectively, indicating their different heat tolerance levels. Overall, short-term heat shock (≥36 °C) caused significantly adverse effects on Bradysia adults, indicating that it could be applied in pest control, and antioxidant system and hsp genes played important roles in their heat tolerance levels.


Assuntos
Dípteros/fisiologia , Resposta ao Choque Térmico , Animais , Antioxidantes/metabolismo , Biomarcadores , Feminino , Expressão Gênica , Resposta ao Choque Térmico/genética , Longevidade , Masculino , Reprodução , Especificidade da Espécie , Temperatura , Fatores de Tempo
13.
J Econ Entomol ; 110(6): 2371-2380, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29045637

RESUMO

Bradysia odoriphaga Yang et Zhang, the Chinese chive root maggot, is a devastating pest of agricultural plants causing significant losses in vegetable crops, edible mushrooms, and humus. To determine the effects of feeding on different host plants and diets on the life parameters of B. odoriphaga and its tolerance to stressful conditions, we analyzed the life-table data of B. odoriphaga reared on Chinese chive (Allium hookeri), Welsh onion (Allium fistulosum), garlic (Allium sativum), oyster mushroom (Pleurotus ostreatus), and humus and assayed its tolerance to heat and insecticides. Furthermore, we assayed the physiological responses of B. odoriphaga reared on different hosts. Development from egg to adult was successfully completed on five hosts. Life table indicated that when reared on Chinese chive and oyster mushroom, B. odoriphaga showed better life parameters (shorter development time, higher survival rate, and fecundity) than on humus and garlic. However, B. odoriphaga larvae fed on humus and garlic better tolerated heat and insecticides than those that were fed Chinese chive and oyster mushroom; larvae survived longer at 38 and 40°C heat shock and at higher insecticide doses. Activities of antioxidant and detoxification enzymes varied significantly in larvae fed on different hosts. Catalase, superoxide dismutase, glutathione S-transferase, and carboxylesterase activities were higher in larva reared on garlic and humus than on Chinese chive and oyster mushroom. These findings indicated that B. odoriphaga preferred liliaceous vegetables and mushroom, and their tolerance against stress increased when reared on humus and garlic. Such basic information can promote targeted pest management in different agricultural fields and allow better understanding of the acclimatization strategy of B. odoriphaga.


Assuntos
Dieta , Dípteros/fisiologia , Resistência a Inseticidas , Termotolerância , Animais , Dípteros/crescimento & desenvolvimento , Feminino , Inseticidas/farmacologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Óvulo/fisiologia , Pupa/crescimento & desenvolvimento
14.
Sci Rep ; 7(1): 3249, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28607407

RESUMO

Garlic, a widely cultivated global vegetable crop, is threatened by the underground pest Bradysia odoriphaga in China. Previous reports indicated that garlic essential oil, of which the dominant components are sulfides or thiosulfinates, exhibits insecticidal activity against pests. However, it is unclear whether the resistance of garlic to B. odoriphaga is related to thiosulfinates. Here, we compared the resistance of 10 garlic cultivars at various growth stages to B. odoriphaga by field investigation and indoor life-table data collection. Furthermore, the relationship between thiosulfinates content and resistance, as well as the toxicity of garlic oil and allicin against B. odoriphaga larvae was determined. Field surveys demonstrated that the garlic cultivars Qixian and Cangshan possessed the highest resistance, while Siliuban and Yishui were the most sensitive. When reared on Qixian, B. odoriphaga larval survival and fecundity declined by 26.2% and 17.7% respectively, but the development time was prolonged by 2.8 d compared with Siliuban. A positive correlation was detected between thiosulfinates content and resistance. Furthermore, garlic oil and allicin exhibited strong insecticidal activity. We screened out 2 pest-resistant cultivars, for which thiosulfinate content was highest. Additionally, the insecticidal activity displayed by sulfides and allcin suggests their potential for exploitation as botanical insecticides.


Assuntos
Alho/química , Nematóceros/efeitos dos fármacos , Compostos Alílicos/análise , Compostos Alílicos/farmacologia , Animais , Feminino , Fertilidade/efeitos dos fármacos , Alho/genética , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Masculino , Nematóceros/crescimento & desenvolvimento , Melhoramento Vegetal , Sulfetos/análise , Sulfetos/farmacologia , Ácidos Sulfínicos/análise , Ácidos Sulfínicos/farmacologia
15.
PLoS One ; 11(10): e0165454, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27788203

RESUMO

BACKGROUND: Bemisia tabaci MEAM1 (Middle East-Asia Minor 1) feeding alters antioxidative enzyme activity in some plant species. Infestation of B. tabaci nymphs decreases Myzus persicae performance on systemic, but not local leaves of tobacco plants. However, it is unclear if B. tabaci nymphs induced antioxidant activities contributing to the aphid resistance. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the relationship between antioxidants induced by nymphs of B. tabaci feeding on tobacco and aphid resistance. The activities of catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and the concentration of hydrogen peroxide (H2O2) were assayed in tobacco leaves at different feeding times following infestation of B. tabaci nymphs. The infestation altered the activities of CAT and POD, but had no significant effect on SOD activity. The highest CAT activity was observed at 15 d after infestation. This was 98.2% greater than control systemic leaves, but 32.6% lower than the control in local leaves. Higher POD activity was recorded in local vs. systemic leaves after 15 d of infestation. POD activity was 71.0% and 112.9% higher in local and systemic leaves, respectively, than in the controls. The changes of CAT, but not POD or SOD activity were correlated to levels of aphid resistance. H2O2 levels were higher in local than in systemic leaves in contrast to CAT activity. Tobacco curly shoot virus mediated virus-induced gene silencing was employed to determine if CAT activation was involved in the aphid resistance induced by B. tabaci nymphs. B. tabaci induced CAT activity decreased when the Cat1 expression was silenced. The performance assay indicated that Cat1 silencing made B. tabaci infested plants a more suitable host for aphids than infested control plants. The aphid survival rate was reduced by 40.4% in infested control plants, but reduced by only 26.1% in Cat1-silenced plants compared to uninfested controls. Also, qPCR results showed that silencing of Cat1 led to the suppression of the B. tabaci mediated PR-2a expression. CONCLUSIONS/SIGNIFICANCE: Aphid resistance in plants infested with B. tabaci nymphs is associated with enhanced antioxidant activities in which CAT may play a dominant role. This resistance probably acted via interactions with SA-mediated defense responses.


Assuntos
Antioxidantes/metabolismo , Afídeos/fisiologia , Catalase/metabolismo , Tabaco/enzimologia , Tabaco/imunologia , Animais , Feminino , Regulação Enzimológica da Expressão Gênica , Peróxido de Hidrogênio/metabolismo , Masculino , Ninfa/fisiologia , Ácido Salicílico/metabolismo , Tabaco/metabolismo
16.
Chem Commun (Camb) ; 52(80): 11959-11962, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27709204

RESUMO

A novel CuI-catalyzed cross-coupling of propargyl epoxides with P(O)H compounds is disclosed. The reaction proceeded efficiently under mild conditions to give 4-phosphoryl 2,3-allenols in good to high yields with excellent selectivity. The utility of the products was demonstrated and a plausible mechanism was also proposed.

17.
Sci Rep ; 6: 32855, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27619006

RESUMO

The onion maggot, Delia antiqua, is a devastating pest of liliaceous crops and current control measures fail to avert pesticide residues, threats to agroecosystem, and costly expenditures. Insect growth regulators (IGRs) are used as trypetid pest chemosterilants for their suppression on adult fertility and fecundity, but their effects on onion flies are unknown. Here, three IGRs (lufenuron, cyromazine, pyriproxyfen) were incorporated into baits to evaluate their effects on onion fly survival, fecundity, fertility, susceptibility of adults in different ages and offspring development. Lufenuron and cyromazine did not affect survival of new-emerged adults, but lufenuron inhibited adult fertility without affecting fecundity, and cyromazine reduced fertility and fecundity. Differently, pyriproxyfen enhanced fecundity within 10 days after treatment, while it reduced adult survival without affecting fertility. The fertility of younger adults was affected by lufenuron and cyromazine whereas the fecundity was affected with cyromazine and pyriproxyfen. For offspring of onion flies treated with lufenuron or cyromazine, most of larvae died within 5 days after hatch, but surviving larvae pupated and emerged normally. Pyriproxyfen did not affect offspring larval survival or pupation but affected pupal emergence. Thus, lufenuron and cyromazine could be potential chemosterilants for onion flies.


Assuntos
Benzamidas/farmacologia , Dípteros/crescimento & desenvolvimento , Hormônios Juvenis/farmacologia , Piridinas/farmacologia , Triazinas/farmacologia , Animais , Dípteros/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Praguicidas/farmacologia , Pupa/crescimento & desenvolvimento
18.
Zootaxa ; 4093(2): 181-200, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27394489

RESUMO

Phylogenetic reconstructions derived from DNA sequence data play a central role in documenting the number of species in a complex. Such analyses are pointing to the existence of many cryptic species, especially in poorly understood groups such as the genus Limnonectes, and the L. kuhlii species complex in particular. To understand the Limnonectes frogs of China, we reconstruct the major matrilineal genealogy of Limnonectes from China and Southeast Asia based on 12S rRNA, tRNAVal and 16S rRNA gene sequences. Based on new data we recognize five species of Limnonectes in China including L. bannaensis, L. fujianensis, L. fragilis, L. taylori (new record), and a new species from southern China and Myanmar. Phylogenetically, the new species is more closely related to the clade comprising L. taylori, L. megastomias, L. isanensis, L. nguyenorum, and L. jarujini from Thailand than to other Chinese species. This study supports previous findings of sympatric members of a species complex that are not each other's closest relatives.


Assuntos
Anuros/anatomia & histologia , Anuros/classificação , Distribuição Animal , Animais , Anuros/genética , Anuros/fisiologia , China , Classificação , Feminino , Masculino , Mianmar , Filogenia , Especificidade da Espécie
20.
Artigo em Inglês | MEDLINE | ID: mdl-24963772

RESUMO

Acrossocheilus kreyenbergii is a small fish and widely distributed in China, for example, Guangxi, Jiangxi, Zhejiang, Anhui, and also found in Henan province. The complete mitochondrial genome sequence of Acrossocheilus kreyenbergii has been obtained with PCR by using the conservative fragment primers of its closely relative species. Just like most of fishes, the gene composition and arrangement of mitochondrial genome sequence of this species are similar to most of other vertebrates', which including 2 rRNA genes, 13 protein-coding genes, 22 tRNA genes, and a non-coding control region with total length of 16,849 bp. There is a 270 bp non-coding fragment (from 15,768 to 16,037) in its control region compared with other fish of genus Acrossocheilus. Most of genes are encoded on Heavy-Strand (H-strand), exclude eight tRNA and ND6 genes, which are encoded on Light-Strand (L-strand). The complete mitochondrial genome sequence of Acrossocheilus kreyenbergii would contribute to better understand population genetics, conservation, and diversity of genus Acrossocheilus.


Assuntos
Cyprinidae/genética , Genes Mitocondriais/fisiologia , Genoma Mitocondrial/fisiologia , Animais , Sequência de Bases , Proteínas de Peixes/genética , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , RNA/genética , RNA Mitocondrial , RNA Ribossômico/genética , RNA de Transferência/genética
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