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The gallium-doped hafnium oxide (Ga-HfO2) films with different Ga doping concentrations were prepared by adjusting the HfO2/Ga2O3 atomic layer deposition cycle ratio for high-speed and low-voltage operation in HfO2-based ferroelectric memory. The Ga-HfO2 ferroelectric films reveal a finely modulated coercive field (Ec) from 1.1 (HfO2/Ga2O3 = 32:1) to an exceptionally low 0.6 MV/cm (HfO2/Ga2O3 = 11:1). This modulation arises from the competition between domain nucleation and propagation speed during polarization switching, influenced by the intrinsic domain density and phase dispersion in the film with specific Ga doping concentrations. Higher Ec samples exhibit a nucleation-dominant switching mechanism, while lower Ec samples undergo a transition from a nucleation-dominant to a propagation-dominant reversal mechanism as the electric field increases. This work introduces Ga as a viable dopant for low Ec and offers insights into material design strategies for HfO2-based ferroelectric memory applications.
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Molybdenum sulfide (MoS2) as an emerging optoelectronic material, shows great potential for phototransistors owing to its atomic thickness, adjustable band gap, and low cost. However, the phototransistors based on MoS2have been shown to have some issues such as large gate leakage current, and interfacial scattering, resulting in suboptimal optoelectronic performance. Thus, Al-doped hafnium oxide (Hf1-xAlx) is proposed to be a dielectric layer of the MoS2-based phototransistor to solve this problem because of the relatively higher crystallization temperature and dielectric constant. Here, a high-performance MoS2phototransistor with Hf1-xAlxO gate dielectric layer grown by plasma-enhanced atomic layer deposition has been fabricated and studied. The results show that the phototransistor exhibits a high responsivity of 2.2 × 104A W-1, a large detectivity of 1.7 × 1017Jones, a great photo-to-dark current ratio of 2.2 × 106%, and a high external quantum efficiency of 4.4 × 106%. The energy band alignment and operating mechanism were further used to clarify the reason for the enhanced MoS2phototransistor. The suggested MoS2phototransistors could provide promising strategies in further optoelectronic applications.
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An asymmetric dual-gate (DG) MoS2field-effect transistor (FET) with ultrahigh electrical performance and optical responsivity using atomic-layer-deposited HfO2as a top-gate (TG) dielectric was fabricated and investigated. The effective DG modulation of the MoS2FET exhibited an outstanding electrical performance with a high on/off current ratio of 6 × 108. Furthermore, a large threshold voltage modulation could be obtained from -20.5 to -39.3 V as a function of the TG voltage in a DG MoS2phototransistor. Meanwhile, the optical properties were systematically explored under a series of gate biases and illuminated optical power under 550 nm laser illumination. An ultrahigh photoresponsivity of 2.04 × 105AW-1has been demonstrated with the structure of a DG MoS2phototransistor because the electric field formed by the DG can separate photogenerated electrons and holes efficiently. Thus, the DG design for 2D materials with ultrahigh photoresponsivity provides a promising opportunity for the application of optoelectronic devices.
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A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.
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Genoma Humano , Genoma Mitocondrial , Ríos , Agricultura , China , Demografía , Humanos , FilogeografíaRESUMEN
The Fujian Tanka people are officially classified as a southern Han ethnic group, whereas they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: (1) the Han Chinese origin, (2) the ancient Daic origin, (3) and the admixture between Daic and Han. This study addressed this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. The southern East Asian predominant haplogroups (e.g., Y-chromosome O1a1a-P203 and O1b1a1a-M95, and mtDNA F2a, M7c1, and F1a1) had relatively high frequencies in Tanka. The interpopulation comparison revealed that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages but are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song dynasty), indicating that they are an indigenous population, not late Daic migrants from southwestern China.
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Cromosomas Humanos Y/genética , ADN Mitocondrial/genética , Genética de Población/métodos , Pueblo Asiatico/genética , China/etnología , ADN Mitocondrial/historia , Etnicidad/genética , Femenino , Pruebas Genéticas/métodos , Haplotipos/genética , Historia Antigua , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
A palladium-catalyzed ring-opening oxo-formal [3 + 2]-cycloaddition reaction of novel donor-acceptor spirovinylcyclopropyl oxindole with 3-oxindole is described. The developed protocol provides facile access to oxo-bispirooxindole derivatives in good yields (up to 82% yield) with excellent diastereoselectivities (up to 20:1 dr).
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Genetic polymorphism analysis of 60 mitochondrial DNA (mtDNA) loci in Chinese Xinjiang Kazak group was conducted in this study. Blood samples from 141 unrelated healthy volunteers were randomly collected from Chinese Kazak ethnic group in Ili, Xinjiang Uygur Autonomous region. Among these mtDNA loci, single nucleotide transition was the most commonly observed variant (87.93%). A total of 25 haplogroups and 79 haplotypes were found in Kazak group, and Haplogroup D4 was the most common haplogroup (21.28%). Among the entire 79 haplotypes, 53 of them were observed for only once, 14 for twice. The haplotype diversity was 0.978 ± 0.005, and the nucleotide diversity was 0.17449. The detection of (CA)n and 9-bp deletion polymorphisms could improve the discrimination power of the mtDNA genetic marker. Moreover, Xinjiang Kazak group was compared with other previously reported groups to infer its genetic background. The present results revealed that Xinjiang Kazak ethnic group was genetically closer related to Xinjiang Uygur, Xinjiang Uzbek and Xinjiang Han populations. Meanwhile, our results also indicated the potential closer genetic relationships among Xinjiang Kazak group with Altaian Kazak as well as Xinjiang Xibe group. In conclusion, this novel mtDNA panel could be effectively utilized for forensic applications. Additionally, to further reveal the genetic background of Chinese Kazak group, more relevant populations and genetic markers should be incorporated in our future study.
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Pueblo Asiatico/genética , ADN Mitocondrial/genética , Técnicas de Genotipaje/métodos , Adulto , Alelos , China/etnología , ADN Mitocondrial/sangre , Etnicidad/genética , Femenino , Frecuencia de los Genes/genética , Marcadores Genéticos , Genética de Población/métodos , Genotipo , Haplotipos/genética , Voluntarios Sanos , Humanos , Masculino , Repeticiones de Microsatélite/genética , Mitocondrias/genética , Filogenia , Polimorfismo Genético/genética , Polimorfismo de Nucleótido Simple/genéticaRESUMEN
A novel palladium-catalysed ring-opening [3 + 2]-annulation of spirovinylcyclopropyl oxindole with α,ß-unsaturated nitroalkenes is reported. A series of spirooxindole derivatives were synthesized in high yields and good to excellent diastereoselectivities. This developed protocol offers a new and efficient pathway for the assembly of spirooxindoles.
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East Asia is widely concerned as one of the important places for the dispersal and evolution of the Anatomically Modern Human (AMH). How the diverse ethnic groups in East Asia originated and diversified is also widely focused by different disciplines of Anthropology. The adoption of genetic data had provided new clues for reconstructing the genetic history of East Asian populations. Genetic studies supported the hypothesis that the AMHs originated from Africa's Homo sapiens at about 200 kilo years ago (kya) and then migrated out of Africa at ~100 kya, followed by expansions into the whole East Asia since their arrival in Southern East Asia at 5~6 kya along the coastal route. Early Homo Sapiens might have genetic contribution to the non-African AMHs. Early settlement, cultural assimilation, population migration and genetic exchanges are crucial in the origination and evolution of East Asia populations. Previous studies made detailed analysis for the genetic history of East Asian populations, which largely resolved the longstanding divergence between archaeology and history. However, this needs further verification by whole-genome sequencing and ancient DNA studies. Here we briefly reviewed the progresses of genetic studies in exploring the population origin, dispersal and diversification in East Asia, which improved understanding of the evolution of East Asian populations. We also prospected the future of genetic studies in revealing the prehistory of East Asians.
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Pueblo Asiatico/genética , Genética de Población , Asia , Evolución Molecular , Genética Humana , Humanos , FilogeniaRESUMEN
In the past decades, the Tai people are increasingly being focused by genetic studies. However, a systematic genetic study of the whole Tai people is still lacking, thus making the population structure as well as the demographic history of this group uninvestigated from genetic perspective. Here we extensively analyzed the variants of hypervariable segments I and II (HVS-I and HVS-II) of mitochondrial DNA (mtDNA) of 719 Tai samples from 19 populations, covering virtually all of the current Tai people's residences. We observed a general close genetic affinity of the Tai people, reflecting a common origin of this group. Taken into account the phylogeographic analyses of their shared components, including haplogroups F1a, M7b and B5a, our study supported a southern Yunnan origin of the Tai people, consistent with the historical records. In line with their diverse cultures and languages, substantial genetic divergences can be observed among different Tai populations that could be attributable to assimilation of maternal components from neighboring populations. Our study further implied the advent of rice agriculture in Mainland Southeast Asia at â¼5 kya (kilo years ago) had greatly promoted the population expansion of the Tai people.
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Pueblo Asiatico/genética , ADN Mitocondrial/genética , Variación Genética , Genética de Población , Asia Sudoriental , Análisis por Conglomerados , Geografía , Haplotipos , Humanos , Dinámica Poblacional , Análisis de Secuencia de ADNRESUMEN
BACKGROUND: Hainan Province is one of the most severe endemic regions with high transmission of Plasmodium falciparum and Plasmodium vivax in China. However, the incidence of P. falciparum and P. vivax has dropped dramatically since 2007 and a national elimination malaria programme (NEMP) was launched after 2010. To better understand the genetic information on P. vivax population before elimination of malaria in Hainan Province, the extent of genetic diversity of P. vivax isolates in Hainan Province was investigated using four polymorphic genetic markers, including P. vivax merozoite surface proteins 1, 3α, and 3ß (pvmsp-1, pvmsp-3α, and pvmsp-3ß) and circumsporozoite protein (pvcsp). METHODS: Isolates of P. vivax (n = 27) from Hainan Province were collected from 2009 to 2010 and pvmsp-1 and pvcsp were analysed by DNA sequencing, respectively. Using polymerase chain reaction-restriction fragment length polymorphism were analysed in pvmsp-3α, and pvmsp-3ß. RESULTS: The DNA sequencing analysis on pvmsp1 revealed that there were three allele types: Salvador-1 (Sal-1), Belem and recombinant (R) types. Among them, Sal-1 type was a dominant strain with eight variant subtypes (88.9%), whereas R- (3.7%) and Belem-type strains (7.4%) had one variant subtypes, respectively. All the isolates carried pvcsp with VK210 type accounting for 85.2% (23/27 isolates) and VK247 type accounting for 14.8% (4/27). Only type A and type B alleles were successfully amplified in pvmsp-3α gene, and a high level of polymorphism was observed in pvmsp-3α. Considering pvmsp-3ß gene, type A was the predominant type in 17 isolates (63%), whereas type B was dominant in only ten isolates (37%). CONCLUSION: The present data indicate that there was high degree of genetic diversity among P. vivax population in Hainan Province of China during the pre-elimination stage of malaria, with 26 unique haplotypes observed among 27 samples.
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Variación Genética , Malaria Vivax/parasitología , Plasmodium vivax/genética , Antígenos de Protozoos/genética , China , Erradicación de la Enfermedad , Humanos , Malaria Vivax/prevención & control , Proteína 1 de Superficie de Merozoito/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Proteínas Protozoarias/genéticaRESUMEN
Pyronaridine and artesunate have been shown to be effective in falciparum malaria treatment. However, pyronaridine is rarely used in Hainan Island clinically, and artesunate is not widely used as a therapeutic agent. Instead, conventional antimalarial drugs, chloroquine and piperaquine, are used, explaining the emergence of chloroquine-resistant Plasmodium falciparum. In this article, we investigated the sensitivity of P. falciparum to antimalarial drugs used in Hainan Island for rational drug therapy. We performed in vivo (28 days) and in vitro tests to determine the sensitivity of P. falciparum to antimalarial drugs. Total 46 patients with falciparum malaria were treated with dihydroartemisinin/piperaquine phosphate (DUO-COTECXIN) and followed up for 28 day. The cure rate was 97.8%. The mean fever clearance time (22.5 ± 10.6 hr) and the mean parasite clearance time (27.3 ± 12.2 hr) showed no statistical significance with different genders, ages, temperatures, or parasite density (P > 0.05). The resistance rates of chloroquine, piperaquine, pyronarididine, and artesunate detected in vitro were 71.9%, 40.6%, 12.5%, and 0%, respectively (P < 0.0001). The resistance intensities decreased as follows: chloroquine > piperaquine > pyronarididine > artesunate. The inhibitory dose 50 (IC50) was 3.77 × 10(-6) mol/L, 2.09 × 10(-6) mol/L, 0.09 × 10(-6) mol/L, and 0.05 × 10(-6) mol/L, and the mean concentrations for complete inhibition (CIMC) of schizont formation were 5.60 × 10(-6) mol/L, 9.26 × 10(-6) mol/L, 0.55 × 10(-6) mol/L, and 0.07 × 10(-6) mol/L, respectively. Dihydroartemisinin showed a strong therapeutic effect against falciparum malaria with a low toxicity.
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Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Adolescente , Adulto , Anciano , Niño , Preescolar , China , Femenino , Humanos , Concentración 50 Inhibidora , Malaria Falciparum/parasitología , Masculino , Persona de Mediana Edad , Pruebas de Sensibilidad Parasitaria , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Historically, the incidence of malaria in the Hainan Province, China has been high. However, since 2001 the malaria incidence in Hainan has decreased due to large-scale, public educational, promotional campaigns and the adoption of preventative measures against malaria following the fast growth of socio-economic development. The present study analysed the correlation between prevention measures and social economic development on the incidence of malaria in Hainan from 2001 to 2013. METHODS: The data of malaria preventative measures and socio-economic development were collected from various cities and counties in Hainan Province from 2001 to 2013 and analysed by the grey correlation analysis system. RESULTS: Seasonal preventive medication and local fiscal revenue increases are significantly related to the reduction of malaria incidence from 2001 to 2013 (R1 = 0.751677; R5 = 0.764795). CONCLUSION: Malaria prevention and control measures and local economic development in Hainan decreased malaria incidence from 2001 to 2013.
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Malaria/economía , Malaria/prevención & control , China/epidemiología , Desarrollo Económico , Humanos , Incidencia , Malaria/epidemiología , Control de Mosquitos/economía , Factores SocioeconómicosRESUMEN
BACKGROUND: In the island of Hainan, the great majority of malaria cases occur in mountain worker populations. Using the behavioral change communication (BCC) strategy, an interventional study was conducted to promote mountain worker malaria prevention at a test site. This study found the methods and measures that are suitable for malaria prevention among mountain worker populations. METHODS: During the Plasmodium falciparum elimination stage in Hainan, a representative sampling method was used to establish testing and control sites in areas of Hainan that were both affected by malaria and had a relatively high density of mountain workers. Two different methods were used: a BCC strategy and a conventional strategy as a control. Before and after the intervention, house visits, core group discussions, and structural surveys were utilized to collect qualitative and quantitative data regarding mountain worker populations (including knowledge, attitudes, and practices [KAPs]; infection status; and serological data), and these data from the testing and control areas were compared to evaluate the effectiveness of BCC strategies in the prevention of malaria. RESULTS: In the BCC malaria prevention strategy testing areas, the accuracy rates of malaria-related KAP were significantly improved among mountain worker populations. The accuracy rates in the 3 aspects of malaria-related KAP increased from 37.73%, 37.00%, and 43.04% to 89.01%, 91.53%, and 92.25%, respectively. The changes in all 3 aspects of KAP were statistically significant (p < 0.01). In the control sites, the changes in the indices were not as marked as in the testing areas, and the change was not statistically significant (p > 0.05). Furthermore, in the testing areas, both the percentage testing positive in the serum malaria indirect fluorescent antibody test (IFAT) and the number of people inflicted decreased more significantly than in the control sites (p < 0.01). CONCLUSION: The use of the BCC strategy significantly improved the ability of mountain workers in Hainan to avoid malarial infection. Educational and promotional materials and measures were developed and selected in the process, and hands-on experience was gained that will help achieve the goal of total malaria elimination in Hainan.
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Enfermedades de los Trabajadores Agrícolas/prevención & control , Enfermedades Endémicas/prevención & control , Conductas Relacionadas con la Salud , Promoción de la Salud/métodos , Malaria Falciparum/prevención & control , Control de Mosquitos/métodos , Enfermedades de los Trabajadores Agrícolas/diagnóstico , Enfermedades de los Trabajadores Agrícolas/epidemiología , Enfermedades de los Trabajadores Agrícolas/parasitología , Animales , Anopheles/parasitología , Antígenos de Protozoos/sangre , Antimaláricos/administración & dosificación , Antimaláricos/uso terapéutico , China/epidemiología , Vestuario , Discos Compactos , Técnica del Anticuerpo Fluorescente Indirecta , Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Insectos Vectores/parasitología , Mosquiteros Tratados con Insecticida , Insecticidas , Internet , Islas , Malaria Falciparum/diagnóstico , Malaria Falciparum/epidemiología , Malaria Falciparum/transmisión , Exposición Profesional , Plasmodium falciparum/inmunología , Prevalencia , Población Rural , Materiales de EnseñanzaRESUMEN
BACKGROUND: The relationship between human gut microbiota and high-altitude hypoxia acclimatization remains highly controversial. This stems primarily from uncertainties regarding both the potential temporal changes in the microbiota under such conditions and the existence of any dominant or core bacteria that may assist in host acclimatization. RESULTS: To address these issues, and to control for variables commonly present in previous studies which significantly impact the results obtained, namely genetic background, ethnicity, lifestyle, and diet, we conducted a 108-day longitudinal study on the same cohort comprising 45 healthy Han adults who traveled from lowland Chongqing, 243 masl, to high-altitude plateau Lhasa, Xizang, 3658 masl, and back. Using shotgun metagenomic profiling, we study temporal changes in gut microbiota composition at different timepoints. The results show a significant reduction in the species and functional diversity of the gut microbiota, along with a marked increase in functional redundancy. These changes are primarily driven by the overgrowth of Blautia A, a genus that is also abundant in six independent Han cohorts with long-term duration in lower hypoxia environment in Shigatse, Xizang, at 4700 masl. Further animal experiments indicate that Blautia A-fed mice exhibit enhanced intestinal health and a better acclimatization phenotype to sustained hypoxic stress. CONCLUSIONS: Our study underscores the importance of Blautia A species in the gut microbiota's rapid response to high-altitude hypoxia and its potential role in maintaining intestinal health and aiding host adaptation to extreme environments, likely via anti-inflammation and intestinal barrier protection.
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Aclimatación , Altitud , Microbioma Gastrointestinal , Hipoxia , Humanos , Animales , Adulto , Masculino , Hipoxia/genética , Ratones , Femenino , Estudios Longitudinales , Mal de Altura/microbiología , Mal de Altura/genética , Persona de Mediana EdadRESUMEN
Although it is widely recognized that the ancestors of Native Americans (NAs) primarily came from Siberia, the link between mitochondrial DNA (mtDNA) lineage D4h3a (typical of NAs) and D4h3b (found so far only in East China and Thailand) raises the possibility that the ancestral sources for early NAs were more variegated than hypothesized. Here, we analyze 216 contemporary (including 106 newly sequenced) D4h mitogenomes and 39 previously reported ancient D4h data. The results reveal two radiation events of D4h in northern coastal China, one during the Last Glacial Maximum and the other within the last deglaciation, which facilitated the dispersals of D4h sub-branches to different areas including the Americas and the Japanese archipelago. The coastal distributions of the NA (D4h3a) and Japanese lineages (D4h1a and D4h2), in combination with the Paleolithic archaeological similarities among Northern China, the Americas, and Japan, lend support to the coastal dispersal scenario of early NAs.
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Genoma Mitocondrial , Humanos , Japón , Américas , China , ADN Mitocondrial/genética , Haplotipos/genética , FilogeniaRESUMEN
The family of Papilionidae (Lepidoptera: Papilionoidea) is a group of butterflies with high ecological and conservation value. The Hengduan Mountains (HMDs) in Southwest China is an important diversity centre for these butterflies. However, the spatial distribution pattern and the climate vulnerability of Papilionidae butterflies in the HDMs remain unknown to date. The lack of such knowledge has already become an obstacle in formulating effective butterfly conservation strategies. The present research compiled a 59-species dataset with 1938 occurrence points. The Maxent model was applied to analyse the spatial pattern of species richness in subfamilies Parnassiinae and Papilioninae, as well as to predict the response under the influence of climate change. The spatial pattern of both subfamilies in the HDMs has obvious elevation prevalence, with Parnassiinae concentrated in the subalpine to alpine areas (2500-5500 m) in western Sichuan, northwestern Yunnan and eastern Tibet, while Papilioninae is concentrated in the low- to medium-elevation areas (1500-3500 m) in the river valleys of western Yunnan and western Sichuan. Under the influence of climate change, both subfamilies would exhibit northward and upward range shifts. The majority of Parnassiinae species would experience drastic habitat contraction, resulting in lower species richness across the HDMs. In contrast, most Papilioninae species would experience habitat expansion, and the species richness would also increase significantly. The findings of this research should provide new insights and a clue for butterfly diversity and climatic vulnerability in southwestern China. Future conservation efforts should be focused on species with habitat contraction, narrow-ranged distribution and endemicity with both in situ and ex situ measures, especially in protected areas. Commercialised collecting targeting these species must also be regulated by future legislation.
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Widespread species that inhabit diverse environments possess large population sizes and exhibit a high capacity for environmental adaptation, thus enabling range expansion. In contrast, narrow-range species are confined to restricted geographical areas and are ecologically adapted to narrow environmental conditions, thus limiting their ability to expand into novel environments. However, the genomic mechanisms underlying the differentiation between closely related species with varying distribution ranges remain poorly understood. The Niviventer niviventer species complex (NNSC), consisting of highly abundant wild rats in Southeast Asia and China, offers an excellent opportunity to investigate these questions due to the presence of both widespread and narrow-range species that are phylogenetically closely related. In the present study, we combined ecological niche modeling with phylogenetic analysis, which suggested that sister species cannot be both widespread and dominant within the same geographical region. Moreover, by assessing heterozygosity, linkage disequilibrium decay, and Tajima's D analysis, we found that widespread species exhibited higher genetic diversity than narrow-range species. In addition, by exploring the "genomic islands of speciation", we identified 13 genes in highly divergent regions that were shared by the two widespread species, distinguishing them from their narrow-range counterparts. Functional annotation analysis indicated that these genes are involved in nervous system development and regulation. The adaptive evolution of these genes likely played an important role in the speciation of these widespread species.
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Ambiente , Murinae , Ratas , Animales , Filogenia , Murinae/genética , China , GenómicaRESUMEN
Himalayas was believed to be a formidably geographical barrier between South and East Asia. The observed high frequency of the East Eurasian paternal lineages in Nepal led some researchers to suggest that these lineages were introduced into Nepal from Tibet directly; however, it is also possible that the East Eurasian genetic components might trace their origins to northeast India where abundant East Eurasian maternal lineages have been detected. To trace the origin of the Nepalese maternal genetic components, especially those of East Eurasian ancestry, and then to better understand the role of the Himalayas in peopling Nepal, we have studied the matenal genetic composition extensively, especially the East Eurasian lineages, in Nepalese and its surrounding populations. Our results revealed the closer affinity between the Nepalese and the Tibetans, specifically, the Nepalese lineages of the East Eurasian ancestry generally are phylogenetically closer with the ones from Tibet, albeit a few mitochondrial DNA haplotypes, likely resulted from recent gene flow, were shared between the Nepalese and northeast Indians. It seems that Tibet was most likely to be the homeland for most of the East Eurasian in the Nepalese. Taking into account the previous observation on Y chromosome, now it is convincing that bearer of the East Eurasian genetic components had entered Nepal across the Himalayas around 6 kilo years ago (kya), a scenario in good agreement with the previous results from linguistics and archeology.
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ADN Mitocondrial/genética , Genética de Población , Genoma Humano , Genoma Mitocondrial , Mitocondrias/genética , Pueblo Asiatico/genética , Cromosomas Humanos Y/genética , ADN Mitocondrial/clasificación , Flujo Génico , Haplotipos , Humanos , India , Nepal , Filogenia , Análisis de Componente Principal , Análisis de Secuencia de ADN , Tibet , Factores de TiempoRESUMEN
Based on 203 specimens belonging to the Rhinolophus "pusillus group" (Mammalia: Chiroptera: Rhinolophidae), univariate and multivariate morphometric analyses using 19 characters were performed to assess the confused species taxonomy. The results indicated that R. pusillus (including calidus, parcus, and szechuanus) in the continental region and Hainan Island of China and "R. cornutus" in Japan are morphologically divergent species. Rhinolophus cornutus should be further split into R. cornutus (including orii, pumilus, and miyakonis) in the main islands of Japan, the Amami and Okinawa Group of the central Ryukyu Archipelago, and Miyako Group of the southern Ryukyus; and R. perditus and R. imaizumii from the Yaeyama Group in the southern Ryukyus. Rhinolophus monoceros from Taiwan is morphologically more similar to species in Japan than to R. pusillus. In addition to R. pusillus, another form that is morphologically similar to species in Japan was recognized from Langzhong in Sichuan Province; this may represent an undescribed species, and further examination is necessary to determine its taxonomic status. Specimens from Guang'an in Sichuan Province, China, are also different from the others, and are characterized by the smallest skull size. Although further studies are required, these specimens were tentatively identified as R. subbadius.