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1.
A herpetofaunal survey of Muni-Pomadze Lagoon, during the main rainy season (May–June), recorded a total of 32 species (13 amphibians and 19 reptiles). Three species are the first records for coastal habitats in Ghana: Kinixys homeana, Calabaria reinhardti, and Bothrophthalmus lineatus. None of the surveyed species are restricted to Ghana. The most diverse herpetofaunal community occurs in grassland thicket, with 26 species (81% of the sampled herpetofauna). Freshwater ponds include 12 species, while only three species (all amphibians) occur in brackish lagoons. Herpetofaunal conservation efforts at these sites should focus on protecting and monitoring grassland coastal thicket and freshwater ponds. Currently, freshwater pond habitats appear to be stable, but coastal thicket is being lost to provide new agricultural land at Muni. Hyperolius reedfrogs, pythons (Python regius) and monitor lizards (Varanus exanthematicus and V. niloticus) appear to offer the greatest potential for undertaking long-term monitoring of the coastal lagoon herpetofauna, because they can be more readily surveyed, and are likely to be sensitive to a broad range of environmental stressors.  相似文献   

2.
Ghana is a developing country in West Africa with a population of about 25 million. Medical illnesses in Ghana overlap with those in developed countries, but infection, trauma, and women’s health problems are much more prominent. Medical practice in rural Africa faces extremely limited resources, a multiplicity of languages (hundreds in Ghana), and presentation of severe illnesses at later stages than seen elsewhere. Despite these limitations, Ghana has established a relatively successful national medical insurance system, and the quality of medical practice is high, at least where it is available. Ghana also has a well-established and sophisticated administrative structure for the supervision of medical education and accreditation, but it has proven very difficult to extend medical training to rural areas, where health care facilities are particularly short of personnel. Physicians are sorely needed in rural areas, but there are few because of the working conditions and financial limitations. Hospital wards and clinics are crowded; time per patient is limited. This article details some of the differences between medical practice in Ghana and that in wealthier countries and how it functions with very limited resources. It also introduces the medical education and training system in Ghana. The following article describes an attempt to establish and maintain a residency training program in General Medicine in a rural area of Ghana.  相似文献   

3.
Data on the detailed stratigraphic range of eight species of gastropod mollusks from the Upper Hauterivian of Ulyanovsk (Volga Region) are presented. A new genus, Trilemma, is established within the family Aporrhaidae. Two new species of this genus, T. russiense sp. nov. and T. striatocarinatum (Sinzow, 1880), are described.  相似文献   

4.
Objectives: While colorectal cancer (CRC) is common, its incidence significantly varies around the globe. The incidence of CRC in West Africa is relatively low, but it has a distinctive clinical pattern and its molecular characteristics have not been studied. This study is one of the first attempts to analyze molecular, genetic, and pathological characteristics of colorectal cancer in Ghana. Methods: DNA was extracted from microdissected tumor and adjacent normal tissue of 90 paraffin blocks of CRC cases (1997–2007) collected at the University of Ghana. Microsatellite instability (MSI) was determined using fragment analysis of ten microsatellite markers. We analyzed expression of mismatch repair (MMR) proteins by immunohistochemistry and sequenced exons 2 and 3 of KRAS and exon 15 of BRAF. Results: MSI analysis showed 41% (29/70) MSI-High, 20% (14/70) MSI-Low, and 39% (27/70) microsatellite-stable (MSS) tumors. Sequencing of KRAS exons 2 and 3 identified activating mutations in 32% (24/75) of tumors, and sequencing of BRAF exon 15, the location of the common activating mutation (V600), did not show mutations at codons 599 and 600 in 88 tumors. Conclusions: Our study found a high frequency of MSI-High colorectal tumors (41%) in Ghana. While the frequency of KRAS mutations is comparable with other populations, absence of BRAF mutations is intriguing and would require further analysis of the molecular epidemiology of CRC in West Africa.  相似文献   

5.
The diagnosis of the genus Khetella Beisel, 1977 is emended, and a new genus, Cretadmete, is described. Two new species belonging to these genera, K. trautscholdi and C. neglecta, are established from the Upper Hauterivian of Ulyanovsk (Volga Region).  相似文献   

6.
描述上扬子区鄂西和湘西中及晚奥陶世桨肋虫类三叶虫Hexacopyge的 5个种 ,包括 2新种 ,即H .turbiniformis和H .yichangensis;讨论Hexacopyge的定义及其与相关属的关系。Hexacopyge在区内分布广、演化快 。  相似文献   

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8.
In this paper I examine the complexity of human forces involved in tree cutting in a Ghanaian forest region. I provide evidence to link the indiscriminate tree-cutting activities of some local communities to the gradual loss of communal control over land and the replacement of kin group control with state property regimes. I point to the interrelated factors of the state's promotion of an exportled development strategy, the intensification of agricultural commercialization, and household and group variations in access to land as all having deleterious impacts on local traditions of sustainable forestry.  相似文献   

9.
Total concentrations of Hg, Al, Fe, As, Pb, Cu, Cr, Ni, Mn, Co, V, and Zn were determined in surface sediments collected from 21 locations within the gold mining impacted Pra River basin in southwestern Ghana. Samples were collected during both the rainy and dry seasons. We hypothesized that in the rural southwestern portion of Ghana, the lack of industrial activities makes artisanal gold mining (AGM) by Hg amalgamation the main source of water resource contamination with heavy metals. Therefore, metals showing concentration trends similar to that of Hg in the studied system are likely impacted by AGM. We found that total-Hg (THg) concentrations in riverine sediments are rather low as compared to other aquatic systems that are impacted by similar mining activities. Measured THg concentrations ranged from 0.018 to 2.917 mg/kg in samples collected in the rainy season and from about 0.01 to 0.043 mg/kg in those collected during the dry season. However, the determination of the enrichment factor (EF) calculated using shale data as reference background values showed signs of severe contamination in most of the sampled sites. In the dry season, THg concentrations correlated positively and significantly to the concentrations of As (r = 0.864, p < 0.01), Cu (r = 0.691, p < 0.05), and Ni (r = 0.579, p < 0.05). Based on our previously stated hypothesis, this could then be an indication of the impact of AGM on ambient levels of these 3 elements. However, the determined concentrations of Cu, and Ni co-varied significantly with Al, suggesting that natural sources do account for the observed levels. Accordingly, both AGM and metal inputs from weathered natural deposits are likely co-responsible for the observed levels of Cu and Ni. In contrast, the lack of correlation between As and Al tends to suggest an impact of AGM on As levels. Overall, our data suggest that besides Hg and to some extent As, the impact of AGM on ambient levels of investigated metals in the gold mining impacted Pra River remains negligible. Finally, the increase in metal concentrations from the dry to the rainy season underlines the impact of changes in hydrologic conditions on levels and fate of metals in this tropical aquatic system.  相似文献   

10.
An ecosystem approach to community health seeks to investigate human health concerns from an ecological perspective. The goal is to improve the health of community members by instituting sustainable ecosystem management strategies that will preserve the health of both the ecosystem and its inhabitants. This article reports on a study in a rural community in Ghana that employed an ecosystem approach to community health planning. Adopting a participatory action research approach, a research team comprised of representatives from various local government departments collaborated with local residents to identify major community health problems, their underlying causes, and possible intervention strategies. The findings illustrate the usefulness of the ecosystem approach to mobilizing community-based interventions to addressing environmental determinants of human health.  相似文献   

11.
高家镇旧石器遗址1998年出土的石制品   总被引:2,自引:0,他引:2       下载免费PDF全文
高家镇遗址是三峡地区一处重要的旧石器时代遗址。遗址埋藏于长江右岸第Ⅲ级基座阶地内。1995年和1998年经过两次发掘,揭露面积456m2,出土石制品2500余件,其中1998年在B区发掘出土石制品719件。石制品类型包括石器、石核、石片和断块等。古人类选取河卵石为原料运用锤击法剥片和加工石器;石器以大型为主,毛坯多为石核和完整石片,砍砸器是石器的主要类型;石器加工较简单,多数单向加工。石器工业具有中国南方旧石器时代主工业鲜明特点。地貌和地层对比,显示该遗址可能与冉家路口遗址同时,处于中更新世晚期。  相似文献   

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13.
         下载免费PDF全文
The Gaojiazhen Paleolithic site, buried in the third terrace of the right bank of the Yangtze River, is located in the Guihuacun village, Gaojiazhen town, Fengdu county, Chongqing. The site was excavated in 1995 and 1998, exposing an area of about 456m2 , as past of the salvage archeological project in the Three Gorges Region. <br>Four stratigraphic layers were identified at the site, with the total thickness of more than 9 meters. Archaeological materials were mainly unearthed from the 4th layer, a layer of alluvial pebbles, 210 ) 215m in thickness, 174 ) 178m above the sea-level. A total of 719 stone artifacts were unearthed. <br>The stone assemblage includes cores ( 340) , flakes ( 192) , chunks ( 102) and retouched tools ( 85) . The general features of these artifacts are summarized as follows: <br>1) Stone raw materials exploited at the site were locally available from ancient riverbeds. More than 5 kinds of raw material were utilized in core reduction and tool manufacture: silicarenite, quartzite, hypabyssal irruptive rock, volcanic breccia rock and lava. Silicarenite is the predominant raw material used for producing stone artifacts at the site. <br>2) The principal flaking technique at the site is direct hammer percussion without core preparation. <br>3) About 813 percent of flakes could have been utilized directly without modification. <br>4) Major blanks for tool fabrication are cores and pebbles ( 1518% ) , followed by complete flakes and incomplete flakes. <br>5) Most tools are large in size. <br>6) Chopper is the dominating tool type, followed by scraper, pick and notch. <br>7) Modified tools appear to be retouched by direct hammer percussion, mostly unifically retouched on the vental surface of blanks. <br>The Gaojiazhen stone tool assemblage shows close tie with the Main Industry in South China. Geomorphological comparison has yielded an age close to upper Middle Pleistocene. Comparative studies indicated that the lithic technology of the Three Gorges Region might serve as a technological link between Paleolithic industries from the Sichuan Basin and that from the lower reach of the Yangtze River.  相似文献   

14.
Fragments of the anterior part of a mandibular rostrum and a maxillary bone of the plesiosaur Polycotylidae indet. from the Karyakino and Beloe Ozero localities of the Saratov Region (Upper Cretaceous, Campanian) are described. The specimens belong to a relatively long-snouted polycotylid with a mandibular symphysis incorporating 13 pairs of teeth. A unique feature of this plesiosaur is the fact that, in the symphysis, the splenial extends to the very anterior end of the rostrum. The polycotylid from the Campanian of the Saratov Region is probably closely related or identical to Georgiasaurus from the Santonian of the Penza Region, in which structural details of the mandibular symphysis remain uncertain.  相似文献   

15.
16.
Psammosteiforms, including Tartuosteus (?) zheleznogorskensis, sp. nov. and Psammosteus cf. P. praecursor Obruchev, from the Lower Frasnian (Upper Devonian) of the Mikhailovskii Mine (Kursk Region) are described. Agnathans, placoderms, crossopterygians, and acanthodians from this locality are determined. The similarity of the Mikhailovskii Fish Assemblage to the assemblage of southern Timan suggests it be assigned to the Upper Timan Regional Stage.  相似文献   

17.
    
Many states expanded their Medicaid programs to low-income adults under the Affordable Care Act (ACA). These expansions increased Medicaid coverage among low-income parents and their children. Whether these improvements in coverage and healthcare use lead to better health outcomes for parents and their children remains unanswered. We used longitudinal data on a large, nationally representative cohort of elementary-aged children from low-income households from 2010 to 2016. Using a difference-in-differences approach in state Medicaid policy decisions, we estimated the effect of the ACA Medicaid expansions on parent and child health. We found that parents’ self-reported health status improved significantly post-expansion in states that expanded Medicaid through the ACA by 4 percentage points (p < 0.05), a 4.7% improvement. We found no significant changes in children’s use of routine doctor visits or parents’ assessment of their children’s health status. We observed modest decreases in children’s body mass index (BMI) of about 2% (p < 0.05), especially for girls.  相似文献   

18.
This article considers the conservation of relict natural habitat in West Africa, especially habitat preserved in traditional sacred groves. Government-sanctioned conservation is contrasted with local grassroots efforts of conservation. Evidence for the ecological value of sacred groves is based on results of a field study of small mammal communities conducted on the Accra Plains of Ghana and on published sources on the conservation and use of sacred groves from various countries. The study employed standard mark-and-recapture techniques for the sampling for terrestrial small mammals, and mist netting for the sampling of bat communities. Pragmatic approaches combining conservation and sustainable use are considered, as are traditional values that have preserved the sacred groves in the past for up to several hundred years in some cases. In part because these groves shelter unique small mammal and plant communities, traditional values and protection mechanisms should be integrated into the newly emerging cultural and religious contexts. The issues encountered during this study reveal that effective conservation involving local peoples requires a concerted interdisciplinary effort. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

19.
落巨福  刘强 《昆虫知识》2009,46(1):77-81
巨型褶翅小蜂Leucospis gigas Fabricius是小蜂总科中体型最大的物种之一,对野生传粉蜜蜂中的一些种类为害很大。在西鄂尔多斯地区首次发现其寄生当地多种植物的重要传粉昆虫沙漠石蜂Megachile(Chalicodoma)desertorum Cockerell后,对其在当地的生活史、成蜂的活动规律、寄主范围以及产卵行为进行了研究。结果表明:巨型褶翅小蜂在西鄂尔多斯地区1年发生1代,当地没有雄性个体,营孤雌生殖。雌蜂寿命30d左右,每年的6月中旬为成蜂活动高峰期。在当地只发现其寄生沙漠石蜂的老熟幼虫,其产卵行为分为3个阶段,即寻找寄主巢室、选择产卵位点与产卵、拉出产卵针。  相似文献   

20.
A new subfamily, genus, and species (Deinotitaninae subfam. nov., Deinotitan orenburgensis gen. et sp. nov.) of the family Mesotitanidae (Titanoptera) are described from the Severodvinian (Upper Permian) of the Orenburg Region. This family belongs to the suborder Mesotitanina; both are recorded in the Paleozoic for the first time. The present finding and unpublished data suggest that the Mesozoic stage of the evolution of the superorder Orthopteroidea might start in the Late Permian. Taxonomy and early evolution of the order Titanoptera are discussed. Minititan nom. nov. is proposed for Microtitan Gorochov, 2003 (nec Microtitan Granger et Gregory, 1943).  相似文献   

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