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OBJECTIVE: To design a cross-inverted triangular pattern to insert compression screw nails for the treatment of femoral neck fractures and to compare the biomechanics of inserting compression screw nails in cross-inverted triangular patterns and inverted triangular patterns. I am very sorry that a corresponding author needs to be added to the article. I do not know how to insert it, so I make a note here. Please check the attachment I uploaded. METHODS: The reasonableness of the model is first analyzed using finite elements. A total of 6 adult human specimens were selected, of which 3 males and 3 females were divided into the A1, B1, and C1 groups and the A2, B2, and C2 groups by the random number table method. The A1 and A2 groups were made into subhead femoral neck fracture models, the B1 and B2 groups were made into trans-neck femoral neck fracture models, and the C1 and C2 groups were made into basal femoral neck fracture models. The right femur of each group had a compression screw nail inserted in the crossed-inverted triangular pattern, and the left femur of each group had a compression screw nail inserted in the inverted triangular pattern. The static compression test was performed by an electronic universal testing machine. The maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head were read according to the pressure-displacement curve drawn in the experiment. RESULTS: The finite element analysis showed that the cross-inverted triangular hollow threaded nail has better conductivity and more stable fixation than the inverted triangular hollow threaded nail. The maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head of the left femur were greater than those of the right femur in the A1, A2, B1, B2 and C2 groups, while the maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head of the left femur were smaller than those of the right femur in the C1 group. There was no statistically significant difference in the maximum load of the femoral neck or the load of 3.00 mm axial displacement of the femoral head between the A1 and A2 groups, the B1 and B2 groups, or the C1 and C2 groups (P > 0.05). After the K-S test, the maximum load of the femoral neck and the load of 3.00 mm axial displacement of the femoral head were normally distributed (P = 0.20), and the LSD-t test was conducted for the two load data; the difference was not statistically significant (P = 0.235). CONCLUSION: The effect of compression screw nails in the cross-inverted triangular pattern was the same in males and females, and stability was better in the fixation of subhead and trans-neck femoral neck fractures. However, its stability in fixation of basal femoral neck fracture is worse than that of the inverted triangular pattern. The cross-inverted triangular hollow threaded nail has better conductivity and more stable fixation than the inverted triangular hollow threaded nail.
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Fraturas do Fêmur , Fraturas do Colo Femoral , Adulto , Humanos , Unhas , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas do Colo Femoral/cirurgia , Fêmur/cirurgia , Fenômenos Biomecânicos , Análise de Elementos Finitos , Fraturas do Fêmur/cirurgiaRESUMO
Tri-n-butyl phosphate (TnBP) is a widely used organophosphate ester, but its effects on the regenerative process under damaging circumstances remain unknown. In the present study, zebrafish larvae were exposed to 0, 50, 100, 200 and 1000 µg/L TnBP, and the caudal fins were cut at 72 hours post fertilization (hpf). First, after exposure to TnBP, the number of total neutrophils decreased together with decreased neutrophils in the tail, and TnBP inhibited chemotaxis. Second, reactive oxygen species (ROS) levels in the zebrafish decreased greatly. Following exposure to TnBP, transcription levels of many genes regulating fin regeneration, such as fgf20a, fgfr1a, bmp2a and bmp4, were significantly downregulated, while inflammatory factors such as cxcl8a, cxcl18b, il-6, and tnfa were abnormally upregulated. In addition, TnBP inhibited the regenerative area after caudal fin amputation. The inflammatory state was adverse during the regenerative process. In summary, TnBP exposure is immunotoxic and decreases oxidative stress in injured zebrafish larvae.
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Neutrófilos , Peixe-Zebra , Animais , Larva , Organofosfatos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genéticaRESUMO
Ecological niche evolution can promote or hinder the differentiation of taxa and determine their distribution. Niche-mediated evolution may differ among climatic regimes, and thus, species that occur across a wide latitudinal range offer a chance to test these heterogeneous evolutionary processes. In this study, we examine (a) how many lineages have evolved across the continent-wide range of the Eurasian nuthatch (Sitta europaea), (b) whether the lineages' niches are significantly divergent or conserved and (c) how their niche evolution explains their geographic distribution. Phylogenetic reconstruction and ecological niche models (ENMs) showed that the Eurasian nuthatch contained six parapatric lineages that diverged within 2 Myr and did not share identical climatic niches. However, the niche discrepancy between these distinct lineages was relatively conserved compared with the environmental differences between their ranges and thus was unlikely to drive lineage divergence. The ENMs of southern lineages tended to cross-predict with their neighbouring lineages whereas those of northern lineages generally matched with their abutting ranges. The coalescence-based analyses revealed more stable populations for the southern lineages than the northern ones during the last glaciation cycle. In contrast to the overlapping ENMs, the smaller parapatric distribution suggests that the southern lineages might have experienced competitive exclusion to prevent them from becoming sympatric. On the other hand, the northern lineages have expanded their ranges and their current abutting distribution might have resulted from lineages adapting to different climatic conditions in allopatry. This study suggests that niche evolution may affect lineage distribution in different ways across latitude.
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Ecossistema , Modelos Teóricos , Animais , Especiação Genética , Passeriformes , FilogeniaRESUMO
When geographic isolation drives speciation, concurrent termination of gene flow among genomic regions will occur immediately after the formation of the barrier between diverging populations. Alternatively, if speciation is driven by ecologically divergent selection, gene flow of selectively neutral genomic regions may go on between diverging populations until the completion of reproductive isolation. It may also lead to an unsynchronized termination of gene flow between genomic regions with different roles in the speciation process. Here, we developed a novel Approximate Bayesian Computation pipeline to infer the geographic mode of speciation by testing for a lack of postdivergence gene flow and a concurrent termination of gene flow in autosomal and sex-linked markers jointly. We applied this approach to infer the geographic mode of speciation for two allopatric highland rosefinches, the vinaceous rosefinch Carpodacus vinaceus and the Taiwan rosefinch C. formosanus from DNA polymorphisms of both autosomal and Z-linked loci. Our results suggest that the two rosefinch species diverged allopatrically approximately 0.5 Ma. Our approach allowed us further to infer that female effective population sizes are about five times larger than those of males, an estimate potentially useful when comparing the intensity of sexual selection across species.
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Tentilhões/classificação , Tentilhões/genética , Especiação Genética , Variação Genética , Cromossomos Sexuais/genética , Animais , Teorema de Bayes , Biologia Computacional , Feminino , Fluxo Gênico , Loci Gênicos , Mapeamento Geográfico , Masculino , Modelos Genéticos , Polimorfismo Genético , Densidade Demográfica , Seleção GenéticaRESUMO
Species-level paraphyly inferred from mitochondrial gene trees is a prevalent phenomenon in taxonomy and systematics, but there are several potential causes that are not easily explained by currently used methods. This study aimed to test the underlying causes behind the observed paraphyly of Streak-breasted Scimitar Babbler (Pomatorhinus ruficollis) via statistical analyses of four mitochondrial (mtDNA) and nine nuclear (nuDNA) genes. Mitochondrial gene trees show paraphyly of P. ruficollis with respect to the Taiwan Scimitar Babbler (Pomatorhinus musicus), but nuclear genealogies support a sister-group relationship. Predictive coalescent simulations imply several hypothetical explanations, the most likely being mitochondrial capture of P. ruficollis by P. musicus for the observed cyto-nuclear incongruence. Further approximate Bayesian computation suggests a unidirectional introgression model with substantial level of gene flow from P. ruficollis to P. musicus during their initial divergence during the Late Pleistocene. This specific observation frames several potential causes for incongruent outcomes of mitochondrial and nuclear introgression in general, and on the whole, our results underscore the strength of multiple independent loci for species delimitation and importance of testing hypotheses that explain disparate causes of mitochondrial gene-tree paraphyly.
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Evolução Molecular , Genes Mitocondriais , Especiação Genética , Modelos Genéticos , Passeriformes/genética , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Fluxo Gênico , Análise de Sequência de DNARESUMO
The streak-breasted scimitar babbler, Pomatorhinus ruficollis, is a polytypic and taxonomically enigmatic babbler common in southern, eastern, and southeastern Asia. To infer the phylogeny of the P. ruficollis, we examined the sequences of two complete mitochondrial genes (2184 bp in total) from fourteen of the fifteen known subspecies, and an additional five nuclear genes (2657 bp in total) from ten subspecies. The mitochondrial phylogeny indicates four major clades with large geographical identity in P. ruficollis and paraphyly of the P. ruficollis species complex, with the inclusion of the olivaceus group of congeneric P. schisticeps. Together with their interbreeding in northern Indochina, we propose to lump this group into P. ruficollis. Analysis of both multilocus networks and species-tree inference recovered poor phylogenetic structure among mainland/ Hainan subspecies and exclusive groupings of the Taiwanese subspecies, consistent with the recent taxonomic revision of its species status. Our analyses also suggest strong incongruence between the morphological-based classification and molecular systematics, implying the strength of multilocus data for taxonomy.
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Passeriformes/genética , Filogenia , Animais , Ásia , DNA Mitocondrial/genética , Passeriformes/classificação , Análise de Sequência de DNARESUMO
Citrullinemia is a rare autosomal recessive disorder characterized by elevated concentrations of citrulline in the blood resulting from malfunction of the urea cycle. It is categorized into two types, types I and II, which are caused by argininosuccinate synthase 1 (ASS1), and citrin (SLC25A13) gene mutations, respectively. In this study, we performed genetic analysis on nine Chinese infants with citrullinemia using next-generation sequencing, which identified a novel mutation (p.Leu313Met) and a rare mutation (p.Thr323Ile, rs1250895424) of ASS1. We also found a novel splicing mutation of SLC25A13: c.1311 + 4_+7del. Functional analysis of the ASS1 missense mutations showed that both significantly impaired the enzyme activity of ASS1, with the p. Thr323Ile mutation clearly affecting the interaction between ASS1 and protein arginine methyltransferase 7 (PRMT7). These findings expand the mutational spectrum of ASS1 and SLC25A13, and further our understanding of the molecular genetic mechanism of citrullinemia in the Chinese population.
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OBJECTIVES: To explore the main factors affecting the knowledge, attitude and practice about influenza and influenza vaccine as well as the intention to receive influenza vaccination among the same group of medical students before (2019) and after (2021) the COVID-19 outbreak. DESIGN: A population-based prospective cohort study. SETTING: A longitudinal cohort study of a selected medical school in Chongqing, China, which ran from 2019 to 2021. PARTICIPANTS: A total of 803 medical students participated in the study in 2019 and only 484 students responded in 2021. The response rate for our survey was only 60.27% due to graduation, emails being abandoned, etc. RESULTS: The influenza vaccination rate of students at this medical school was 6.7% in 2019, compared with 25.8% in 2021. The awareness rate of medical students about influenza and influenza vaccine was 82.8% in 2019 and 86% in 2021, and there was no significantly statistical difference between the 2 years (p=0.134); the number of medical students with supportive attitude towards influenza vaccine was 95.1% in 2019 and 97.1% in 2021, and there was no statistically significant difference between the 2 years (p=0.078); the number of students who actively learnt about knowledge related to influenza vaccine rose from 183 (22.8%) in 2019 to 195 (40.3%) in 2021. CONCLUSIONS: The COVID-19 outbreak prompted an increase in influenza vaccination rates among medical students in Chongqing, with almost all students (96.0%) believing that the spread of COVID-19 promoted their knowledge about influenza and influenza vaccine, and the vast majority (74.8%) believing that the spread of COVID-19 promoted their willingness to receive influenza vaccine.
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COVID-19 , Vacinas contra Influenza , Influenza Humana , Estudantes de Medicina , COVID-19/epidemiologia , COVID-19/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Vacinas contra Influenza/uso terapêutico , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Estudos Longitudinais , Estudos ProspectivosRESUMO
An FPGA-Based Image Guided Surgery Hardware Platform has been designed and implemented in this paper. The hardware platform can provide hardware acceleration for image guided surgery. It is completed with a video decoder interface, a DDR memory controller, a 12C bus controller, an interrupt controller and so on. It is able to perform real time video endoscopy image capturing in the surgery and to preserve the hardware interface for image guided surgery algorithm module.
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Endoscopia/métodos , Cirurgia Assistida por Computador/instrumentação , Algoritmos , Desenho de Equipamento , SoftwareRESUMO
Osteopontin (OPN) involves in tumor formation, and strongly correlated with the tumor progression. It was overexpressed in human esophageal squamous cell carcinoma (ESCC). To study the molecular mechanisms of OPN in ESCC, we examined its roles in inhibiting proliferation and invasion of ECA-109 (esophageal squamous cell carcinoma) cells. The expression of OPN gene was knockdown by RNA interference (RNAi) in the Eca-109 cell. The transcription level of OPN was to detect by reverse transcription-quantitative PCR (RT-qPCR). Western blot assay was performed to detect the expression of OPN, Caspase-3,Caspase-8, Caspase-9, ERK1/2, phospho-ERK1/2 and MMP2 after RNAi. The cell proliferation and apoptosis were detected by MTT and Hoechst33342 assay. Transwell inserts was used for detecting ECA-109 cell's migration ability. The results shown that the level of OPN mRNA and protein was significantly reduced after RNAi. Proliferation and migration of cell line (ECA-109) was significantly inhibited in vitro. The protein phosphorylation and activation of ERK1/2 in the OPN RNAi group reduced significantly than the negative control groups. In Conclusion, the proliferation and migration of human ESCC can be inhibited by RNAi-targeting OPN. OPN can promote the expression of MMP2 through the ERK signaling pathways. OPN could serve as a potential therapeutic target for human ESCC.
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Knowledge is limited about the bioaccumulation of persistent halogenated compounds (PHCs) in terrestrial wildlife. Several PHCs, including dichlorodiphenyltrichloroethane (DDT) and its metabolites (designated as DDTs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), decabromodiphenylethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), and stable isotopes (δ(15)N and δ(13)C) were analyzed in the muscle of four terrestrial passerines, Parus major, Copsychus saularis, Pycnonotus sinensis and Pycnonotus jocosus, from a nature reserve in South China. P. major had the highest PHC concentrations, with median values of 1060, 401, 92, 25 and 0.3 ng/g lipid weight for DDTs, PCBs, PBDEs, DBDPE and BTBPE, respectively. Fractions of DDT in P. jocosus and PCBs 153, 118 and 180 in C. saularis were higher compared with the other species. The inter-species differences in PHC concentrations and profiles could be attributed to the differences in trophic level, diet, living habits and metabolic capacity among the birds.
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Poluentes Ambientais/análise , Éteres Difenil Halogenados/análise , Hidrocarbonetos Clorados/análise , Passeriformes , Animais , China , Monitoramento Ambiental , Músculos/química , Especificidade da EspécieRESUMO
Little information is available on the bioaccumulation of halogenated flame retardants (HFRs) in terrestrial ecosystem. Eggs of light-vented bulbul, yellow-bellied prinia, plain prinia, and dark green white-eye were collected from an ecological station in the Pearl River Delta, South China to investigate the occurrence of polybrominated diphenyl ethers (PBDEs) and several alternative HFRs, including decabromodiphenyl ethane (DBDPE), dechlorane plus (DP), hexabromobenzene (HBB), pentabromoethylbenzene (PBEB), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), pentabromotoluene (PBT), and 2,3,5,6-tetrabromo-p-xylene (pTBX). Concentrations of PBDEs, DBDPE, DP, HBB, PBEB, BTBPE, PBT, and pTBX ranged from 53-423, 6.1-609, 4.6-268, not detected (nd)-10, nd-1.4, nd-1.7, nd-7.5, and nd-3.2 ng g(-1) lw, respectively. Light-vented bulbul exhibited significantly lower levels of PBDEs, DBDPE, DP, and HBB than other three bird species due to its phytophagy and the other three bird species' insectivores. PBDEs were the predominant HFRs in bird eggs, followed by DBDPE and DP. Significant negative relationship between the fraction of anti-DP and DP concentrations was observed in bird eggs, suggesting that DP levels play an important role in determining the isomeric composition. Anti-Cl11-DP, the dechlorinated products of DP, was found in bird eggs with concentrations ranging from nd to 0.86 ng g(-1) lw and its source is worth further research.
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Monitoramento Ambiental , Poluentes Ambientais/análise , Retardadores de Chama/análise , Óvulo/metabolismo , Animais , Aves , China , Poluentes Ambientais/metabolismo , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/metabolismo , Óvulo/química , RiosRESUMO
Thirty-two light-vented bulbuls (Pycnonotus sinensis) were collected from six sampling sites in Guangdong Province, South China to investigate the geographical variation on the occurrence of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs). Concentrations of PCBs and DDTs in the pectoral muscle of light-vented bulbul ranged from 140 to 73,000 ng/g lipid weight (lw) and 12 to 4600 ng/g lw, respectively. PCB concentrations were significantly higher in birds from e-waste site compared to other sampling sites (mean, 18,000 vs 290 ng/g lw, p<0.0001), implying that PCBs mainly came from e-waste recycling activities. No significant differences for DDT levels were observed among the sampling sites (p=0.092). Differences in PCB homologue profiles among the sampling sites were found and can be probably ascribed to different local contamination sources. p,p'-DDE (>80%) was the most abundant component of DDTs in birds. Compositional pattern of DDTs suggested that historical residue was the main source of DDT. The toxic equivalent (TEQ) concentrations had significant positive correlations with PCB concentrations, indicating that elevated PCB levels may have adverse effects on light-vented bulbuls.
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DDT/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Bifenilos Policlorados/metabolismo , Migração Animal , Animais , China , Passeriformes/metabolismo , Medição de RiscoRESUMO
Dechlorane Plus (DP) isomers were examined in common kingfishers (Alcedo atthis) and their prey fishes collected from an electronic waste (e-waste) recycling site and a reference site in South China, to investigate the possible influence of DP residue levels on the isomeric compositions. ∑DP (sum of syn-DP and anti-DP) concentrations in kingfishers from the e-waste recycling site ranged from 29 to 150 (median of 58) ng/g lipid weight (lw), which were one order of magnitude greater than those from the reference site (median = 3.9 ng/g lw). The isomer fractions of anti-DP (f(anti)) in kingfishers from the e-waste recycling site (mean of 0.65) were significantly smaller than those from the reference site (0.76). Additionally, the f(anti) values were negatively correlated to logarithm of ∑DP concentrations in the kingfishers (r(2) = 0.41, p < 0.0001). These results suggested that DP residue levels could influence its isomeric composition in the piscivorous bird.
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Aves/metabolismo , Resíduo Eletrônico , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Retardadores de Chama/metabolismo , Hidrocarbonetos Clorados/metabolismo , Compostos Policíclicos/metabolismo , Animais , China , Poluição Ambiental/estatística & dados numéricos , Isomerismo , ReciclagemRESUMO
The Dinghushan Biosphere Reserve is a nature reserve and a site for the study of tropical and subtropical forest ecosystems. Rapid industrialization and intensive electronic waste-recycling activities around the biosphere reserve have resulted in elevated levels of industrial organic contaminants in the local environment that may cause adverse effects on wildlife that inhabits this area. In the present study, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and 2 alternative brominated flame retardants (BFRs)-decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE)-were investigated in the biosphere reserve and a reference site by using the kingfisher (Alcedo atthis) as a bioindicator. Residue concentrations in kingfishers from the Dinghushan Biosphere Reserve ranged from 490 ng/g to 3000 ng/g, 51 ng/g to 420 ng/g, 0.44 ng/g to 90 ng/g, and 0.04 ng/g to 0.87 ng/g lipid weight for ∑PCBs, ∑PBDEs, DBDPE, and BTBPE, respectively. With the exception of the BTBPE, these levels were 2 to 5 times higher than those detected in kingfishers from the reference site. The contaminant patterns from the biosphere reserve were also different, with larger PCB contributions in comparison with the reference site. The estimated predator-prey biomagnification factors (BMFs) showed that most of the PCB and PBDE congeners and BTBPE were biomagnified in kingfishers from the biosphere reserve. The calculated toxic equivalent quantity (TEQ) concentrations of major coplanar PCB congeners in kingfishers from the biosphere reserve ranged from 18 pg/g to 66 pg/g wet weight, with some of these TEQ concentrations reaching or exceeding the levels known to impair bird reproduction and survival.
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Aves/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Bifenilos Policlorados/metabolismo , Animais , China , Resíduo Eletrônico , Retardadores de Chama/metabolismoRESUMO
Brominated flame retardants (BFRs) including polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), were investigated in common kingfishers (Alcedo atthis) and their prey fish from an electronic waste-recycling site in south China. Elevated BFR residues were detected in the kingfishers, with median concentrations of 8,760, 12, and 7.7 ng/g lipid weight for total PBDEs, DBDPE, and BTBPE, respectively. The calculated predator/prey biomagnification factors (BMFs) were greater than unity for most of the investigated PBDE congeners, with relatively higher values for some hexa-, hepta-, and octa-BDEs (e.g., BDEs 153, 183, 196, 197, 202, and 203). The average BMFs ranged 0.10 to 0.77 and 1.90 to 3.60 for DBDPE and BTBPE, respectively. The BMFs for BTBPE were comparable to or even greater than those for some tri- to penta-BDEs in certain predator/prey pairs, indicating potentially high environmental risks of this compound. Significantly higher concentration ratios of BDEs 202 and 207 to BDE 209 were observed in the kingfishers compared with their prey fish, and these ratios were negatively correlated with the logarithm of BDE 209 concentrations in the kingfishers. This may indicate biotransformation of BDE 209 to BDEs 202 and 207 in these birds. This is the first assessment of the biomagnification potentials of DBDPE and BTBPE in a wild piscivorous bird.
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Aves/metabolismo , Bromobenzenos/metabolismo , Resíduo Eletrônico , Poluentes Ambientais/metabolismo , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/metabolismo , Animais , Biotransformação , China , Monitoramento Ambiental , Peixes/metabolismo , Cadeia AlimentarRESUMO
Polybrominated diphenyl ethers (PBDEs), decabromodiphenyl ethane (DBDPE), polybrominated biphenyls (PBBs) and pentabromotoluene (PBT) were investigated in light-vented bulbul (LVB), long-tailed shrike (LTS) and oriental magpie-robin (OMR) collected from seven sampling sites in South China. ∑PBDEs, DBDPE, PBB 153, and PBT levels ranged from 35 to 15,000, no detected (nd)-130, nd-6800, and nd-6.8 ng/g lipid weight, respectively. Positive correlations were found between δ(15)N values and brominated flame retardant (BFR) concentrations. The BFR geographic pattern indicated that PBDEs were linked to e-waste recycling and local industry activities as well as urbanization; PBB 153 was derived from e-waste; DBDPE was mainly come from local industry activities; and no specific source was observed for PBT. PBDE congener profiles were found to be depended on bird species and sampling sites with relatively high abundances of lower brominated congeners in e-waste site and significantly higher abundance of BDE153 in LTS and OMR than in LVB.
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Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Retardadores de Chama/metabolismo , Hidrocarbonetos Bromados/metabolismo , Passeriformes/metabolismo , Animais , China , Eletrônica , Exposição Ambiental , Poluentes Ambientais/análise , Retardadores de Chama/análise , Hidrocarbonetos Bromados/análise , Resíduos IndustriaisRESUMO
Diastereoisomers and enantiomers of hexabromocyclododecane (HBCD) were determined in muscle and stomach contents of three terrestrial passerine birds from e-waste, urban and rural locations in South China. The highest HBCD concentration was found at the urban site, followed by the e-waste site, suggesting that HBCD was linked to urbanization and industrialization, as well as e-waste recycling activities. Trophic magnification for α-HBCD was observed in the terrestrial food chain. Diastereisomeric pattern in birds showed the predominance of α-isomer, with a minor contribution of γ-isomer. The enantiomeric analysis revealed a preferential enrichment of (-)-α-HBCD and (+)-γ-HBCD. The similarity in enantiomeric fractions of HBCD isomers between muscle and stomach contents of birds suggested that dietary uptake may be responsible for the observed nonracemic distribution of HBCD isomers in the studied birds although in vivo enantioselective biotic processes cannot be ruled out.
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Resíduo Eletrônico , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Hidrocarbonetos Bromados/metabolismo , Passeriformes/metabolismo , Animais , China , Poluição Ambiental/estatística & dados numéricos , Conteúdo Gastrointestinal/química , Músculos/metabolismo , EstereoisomerismoRESUMO
The phylogenetic relationships among subspecies of Pomatorhinus ruficollis are not clear. In this paper we sequenced two mitochondrial genes (Cyt b and ND2, in total 2 184 bp) and examined twenty individuals representing ten of the eleven subspecies of P. ruficollis in China. Molecular phylogenetic trees were reconstructed using maximum parsimony, maximum likelihood and Bayesian inference methods, with P. ruficollis and P. schisticeps as in-groups, P. montanus, P. ochraceiceps, P. ferruginosus and Xiphirhynchus superciliaris as out-groups. Results indicated that P. ruficollis was paraphyletic, in which P. schisticeps was embedded, and was divided into three phylogeographic groups: southwestern China group, southeastern China group and central China group. Our results also suggested discordances between phylogenetic relationships and morphological characteristics, and clarified some intraspecific taxonomic debates.
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Passeriformes/classificação , Filogenia , Animais , China , DNA Mitocondrial/genética , Dados de Sequência Molecular , Passeriformes/genéticaRESUMO
Understory birds in monsoon evergreen broadleaved forest of Mengyang, Xishuangbanna, Yunnan were sampled using mist nets from October 2008 to March 2009. A total of 1423 individuals of 90 species belonging to 28 families and 7 orders were captured, among which there are 8 dominant bird species, i.e., Sliver-breasted Broadbill (Serilophus lunatus), Brown-cheeked Fulvatta (Alcippe poioicephala), White-throated Bulbul (Alophoixus pallidus), Golden-spectacled Warbler (Seicercus burkii), White-tailed Robin (Cinclidium leucurum), Black-breasted Thrush (Turdus dissimilis), Streak-Breasted Jungle Babbler (Pellorneum ruficeps), and Buff-breasted Jungle Babbler (Trichastoma tickelli). Resident birds, the major composition of the understory birds, accounted for 89.3 percent of total captures. The mean capture rate was 9.0+-3.7 individuals/(100 net-hours) and it differed significantly between months, highest in December 2008 (12.5+-1.3)individuals/(100 net-hours), lowest in February 2009 (5.2+-0.6) individuals/(100 net-hours). The most significant characteristic of understory birds in Xishuangbanna is more species abundance and lower species density compared to understory bird composition of South China. Another characteristic is that no obvious dominance pattern was observed in Babbler species. We also noticed that silver-breasted Broadbill, National Key Protection Bird, is the most abundance species in our captures, thus their habitat require further protection.