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1.
One new genus of the spider subfamily Coelotinae, Flexicoelotes
gen. n., with five new species is described from southern China: Flexicoelotes
huyunensis
sp. n. (female), Flexicoelotes
jiaohanyanensis
sp. n. (male and female), Flexicoelotes
jinlongyanensis
sp. n. (male and female), Flexicoelotes
pingzhaiensis
sp. n. (female), Flexicoelotes
xingwangensis
sp. n. (male and female). 相似文献
2.
Latitudinal comparison of altitudinal changes in forest structure,leaf-type,and species richness in humid monsoon Asia 总被引:10,自引:0,他引:10
M. Ohsawa 《Plant Ecology》1995,121(1-2):3-10
A new template for mountain vegetation zonation along latitudinal gradients is proposed for examining geographical pattern of various forest attributes in humid monsoon Asia. The contrasting temperature regime in tropical and temperate mountains, i.e., the former is a non-seasonal, temperature-sum controlled environment, and the latter is a seasonal, low temperature limiting environment, leads to different altitudinal patterns of tree height distribution and species richness. In the tropical mountains, both tree height and species richness decrease steeply, and the tree height often stepwise. The decline of tree height and species diversity in the temperate mountains is far less pronounced except near the forest limit. Both trends are explained by their temperature regime. 相似文献
3.
4.
Francielly Cristina Machado Renata Prandini Adum de Matos Fernando Lucas Primo Antonio Claudio Tedesco Paula Rahal Marília Freitas Calmon 《Bioorganic & medicinal chemistry》2019,27(9):1882-1890
Curcumin, a natural compound has several antineoplastic activities and is a promising natural photosensitizer used in photodynamic therapy. However, its low solubility in physiological medium limit the clinical use of curcumin. This study aimed to analyze the action of curcumin-nanoemulsion, a new and well-designed Drug Delivery System (DDS+) molecule, used as a photosensitizing agent in photodynamic therapy in an in vitro breast cancer model, MCF-7 cells. The empty nanoemulsion fulfils all necessary requirements to be an excellent DDS. Furthermore, the use of curcumin-nanoemulsion in photodynamic therapy resulted in a high phototoxic effect after activation at 440?nm, decreasing to <10% viable tumor cells after two irradiations and increasing the reactive oxygen species (ROS) production. The use of curcumin-nanoemulsion associated with photodynamic therapy resulted in an increase in the levels of caspase 3/7 activity for the studied MCF-7 cell model, indicating that this therapy triggers a cascade of events that lead to cell death, such as cellular apoptosis. In conclusion, curcumin-nanoemulsion proved to be efficient as a photosensitizing agent, had phototoxic effects, significantly decreased the proliferation of MCF-7 cells and stimulating the ROS production in combination with photodynamic therapy, so, this formulation has a great potential for use in treatment of breast cancer. 相似文献
5.
6.
This article analyses long-term changes in the mean age at menarche (MAM) as a biological indicator of changes in the standard of living in Indonesia. It finds that MAM was about 15.5 for birth cohorts in the late-19th century, decreasing to 14.5 by the 1930s, at which level it stagnated until the gradual decrease resumed since the early 1960s to around 12.5 in the mid-2000s. The article considers that long-term improvements in nutrition, educational attainment and health care explain these trends. An international comparison of long-term changes finds that MAM in Indonesia was much lower than in Korea and China until respectively 1970 and 1990, but comparable to Japan until 1950 and to Malaysia until 1930. The article presents reasons why these differences are unlikely to be related to dissimilarities in climate and ethnicity, and concludes that they are indicative of relative standards of living. 相似文献
7.
Cameron D. Siler Jamie R. Oaks Luke J. Welton Charles W. Linkem John C. Swab Arvin C. Diesmos Rafe M. Brown 《Journal of Biogeography》2012,39(7):1217-1234
Aim We examine the genetic diversity within the lizard genus Gekko in the Philippine islands to understand the role of geography and geological history in shaping species diversity in this group. We test multiple biogeographical hypotheses of species relationships, including the recently proposed Palawan Ark Hypothesis. Location Southeast Asia and the Philippines. Methods Samples of all island endemic and widespread Philippine Gekko species were collected and sequenced for one mitochondrial gene (NADH dehydrogenase subunit 2) and one nuclear gene (phosducin). We used maximum likelihood and Bayesian phylogenetic methods to derive the phylogeny. Divergence time analyses were used to estimate the time tree of Philippine Gekko in order to test biogeographical predictions of species relationships. The phylogenetic trees from the posterior distribution of the Bayesian analyses were used for testing biogeographical hypotheses. Haplotype networks were created for the widespread species Gekko mindorensis to explore genetic variation within recently divergent clades. Results Both maximum likelihood and Bayesian phylogenetic analyses indicated that Philippine Gekko species are a diverse clade with a long history in the archipelago. Ancestral range reconstruction and divergence time analyses suggest a Palawan microcontinental origin for this clade, coinciding with Palawan’s separation from Asia beginning 30 Ma, with subsequent diversification in the oceanic Philippine islands. The widespread species G. mindorensis and G. monarchus diversified in the late Miocene/early Pliocene and are potentially complexes of numerous undescribed species. Main conclusions The view of the Philippine islands as a ‘fringing archipelago’ does not explain the pattern of species diversity in the genus Gekko. Philippine Gekko species have diversified within the archipelago over millions of years of isolation, forming a large diverse group of endemic species. Furthermore, the Philippine radiation of gekkonid lizards demonstrates biogeographical patterns most consistent with stochastic colonization followed by in situ diversification. Our results reveal the need to consider deeper time geological processes and their potential role in the evolution of some Philippine terrestrial organisms. 相似文献
8.
East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided. 相似文献
9.
Population structure and colonization of Bactrocera dorsalis (Diptera: Tephritidae) in China,inferred from mtDNA COI sequences 总被引:1,自引:0,他引:1
The oriental fruit fly, Bactrocera dorsalis, is a serious pest of fruits and vegetables in South‐east Asia, and, because of quarantine restrictions, impedes international trade and economic development in the region. Revealing genetic variation in oriental fruit fly populations will provide a better understanding of the colonization process and facilitate the quarantine and management of this species. The genetic structure in 15 populations of oriental fruit fly from southern China, Laos and Myanmar in South‐east Asia was examined with a 640‐bp sequence of the mitochondrial cytochrome oxidase subunit I (COI) gene. The highest levels of genetic diversity were found in Laos and Myanmar. Low to medium levels of genetic differentiation (FST ≤ 0.134) were observed among populations. Pooled populations from mainland China differed from those in Laos and Myanmar (FST = 0.024). Genetic structure across the region did not follow the isolation‐by‐distance model. The high genetic diversity observed in Laos and Myanmar supports the South‐east Asian origin of B. dorsalis. High genetic diversity and significant differentiation between some populations within mainland China indicate B. dorsalis populations have been established in the region for an extended period of time. High levels of genetic diversity observed among the five populations from Hainan Island and similarity between the Island and Chinese mainland populations indicate that B. dorsalis was introduced to Hainan from the mainland and has been on the island for many years. High genetic diversity in the recently established population in Shanghai (Pudong) suggests multiple introductions or a larger number of founders. 相似文献
10.
The persistence and conservation of Borneo’s mammals in lowland rain forests managed for timber: observations, overviews and opportunities 总被引:1,自引:0,他引:1
Lowland rainforests on Borneo are being degraded and lost at an alarming rate. Studies on mammals report species responding
in various ways to habitat changes that occur in commercial forestry concessions. Here we draw together information on the
relationship between the ecological, evolutionary, and biogeographic characteristics of selected Bornean non-volant mammals,
and their response to timber harvesting and related impacts. Only a minority of species show markedly reduced densities after
timber harvesting. Nonetheless there are many grounds for concern as various processes can, and often do, reduce the viability
of wildlife populations. Our review of what we know, and of current understanding, helps predict mammalian dynamics and subsequent
mammal-induced ecosystem changes in logged forests. We identify groups of mammal species that, although largely unstudied,
are unlikely to tolerate the impacts associated with timber harvesting. On a positive note we find and suggest many relatively
simple and low-cost ways in which concession management practices might be modified so as to improve the value of managed
forests for wildlife conservation. Improving forest management can play a vital role in maintaining the rich biodiversity
of Borneo’s tropical rain forests. 相似文献