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1.
Although prenatal genetic diagnosis can usually provide prospective parents with information as to whether their fetus is affected with certain genetic conditions, the presence of twins and the uncertainty about the phenotype of some chromosome variations pose a major dilemma and make genetic counselling very difficult. Here, a case report of an unusual chromosome aberration (pericentric inversion of chromosome no. 17) in a twin pregnancy which was originally suspected to be monoamniotic but later proved to have two sacs was presented.  相似文献   
2.
Although contract sugarcane farming is the most dominant and popular land use among farmers in Nzoia Sugarbelt, results from a 2007 study suggests that the intended goal of increasing farmers’ incomes seems to have failed. With a mean monthly income of Kenya Shillings 723 (US $ 10) from an average cane acreage of 0.38 hectares, it would be difficult for a household of eight family members to meet their basic needs and lead a decent life. Analysis of farmer statements showed that up to 86% of the changes in net income were significantly determined by six cost variables as a group (i.e., acreage, tillage costs, seedcane costs, transport costs, yield, and farmer’s education level). Area under sugarcane had the greatest influence on net income whereby an increase in one hectare under cane would result in an increase of Kenya Shillings 110,427 in net income (per crop cycle of 21 months), holding other variables constant. This translates into Kenya shillings 5,258 per month (or 175 per day per household, or for a family of eight people—KES 22 or US $ 10) from an average cane acreage of 0.38 hectares, it would be difficult for a household of eight family members to meet their basic needs and lead a decent life. Analysis of farmer statements showed that up to 86% of the changes in net income were significantly determined by six cost variables as a group (i.e., acreage, tillage costs, seedcane costs, transport costs, yield, and farmer’s education level). Area under sugarcane had the greatest influence on net income whereby an increase in one hectare under cane would result in an increase of Kenya Shillings 110,427 in net income (per crop cycle of 21 months), holding other variables constant. This translates into Kenya shillings 5,258 per month (or 175 per day per household, or for a family of eight people—KES 22 or US 0.3) per member, which is far below the international standard of absolute poverty. Key net income depressors were tillage, seedcane, and transportation costs, all of which were determined by the company with no input from farmers. To bridge income gaps between the company and farmers in favor of sustainable community livelihoods, this paper argues strongly for the need to institutionalize Corporate Social Responsibility within the daily operations of the company particularly to address net-income depressors. Ten key building blocks for such a policy for Nzoia Sugar Company are suggested, based on farmers’ responses and ethical considerations.  相似文献   
3.
Landform-based physiographic maps, also called land systems inventories, have been widely and successfully used in undeveloped/rural areas in several locations, such as Australia, the western United States, Canada, and the British ex-colonies. This paper presents a case study of their application in a developed semi-urban/suburban area (Segovia, Spain) for land use planning purposes. The paper focuses in the information transfer process, showing how land use decision-makers, such as governments, planners, town managers, etc., can use the information developed from these maps to assist them. The paper also addresses several issues important to the development and use of this information, such as the goals of modern physiography, the types of landform-based mapping products, the problem of data management in developed areas, and the distinctions among data, interpretations, and decisions.  相似文献   
4.
The World Health Organization (WHO)/United Nations Children??s Fund (UNICEF) Joint Monitoring Programme (JMP) for Water Supply and Sanitation was designed to provide reference figures for access in individual countries to safe water. The JMP is based on non-administrative or nongovernment data from national-level surveys such as the Multiple Indicator Clusters Survey (MICS) or Demographic Health Survey. In the 2007 JMP report, India is noted to have water supply coverage of 89% (95% in urban areas and 85% in rural areas) compared to the Government of India estimates of 95%. The central state of Madhya Pradesh is noted by the Government of India to have coverage of 60%. However, the definition of access to safe water currently does not consider the quality or safety of the water being consumed. This paper, therefore, presents results from the application of a statistical tool (random multiple cluster technique??termed Rapid Assessment of Drinking Water Quality [RADWQ]) to Indore Zone in Madhya Pradesh. When results provided by the RADWQ technique are compared to the JMP MICS data, coverage levels reported in the JMP are reduced by up to 40% due to the high risk of microbiological (thermotolerant coliforms) contamination. In Indore Zone, the coverage of safe water reduced from 42% to 25% through the inclusion of the water safety parameters. The study recommends the inclusion of water quality/safety data in reported data under the UNICEF/WHO JMP.  相似文献   
5.
Gidgee skinks (Egernia stokesii) form large social aggregations in rocky outcrops across the Flinders Ranges in South Australia. Group members share refuges (rock crevices), which may promote parasite transmission. We measured connectivity of individuals in networks constructed from patterns of common crevice use and observed patterns of parasitism by three blood parasites (Hemolivia, Schellackia and Plasmodium) and an ectoparasitic tick (Amblyomma vikirri). Data came from a 1-year mark-recapture study of four populations. Transmission networks were constructed to represent possible transmission pathways among lizards. Two lizards that used the same refuge within an estimated transmission period were considered connected in the transmission network. An edge was placed between them, directed towards the individual that occupied the crevice last. Social networks, a sub-set of same-day only associations, were small and highly fragmented compared with transmission networks, suggesting that non-synchronous crevice use leads to more transmission opportunities than direct social association. In transmission networks, lizards infested by ticks were connected to more other tick-infested lizards than uninfected lizards. Lizards infected by ticks and carrying multiple blood parasite infections were in more connected positions in the network than lizards without ticks or with one or no blood parasites. Our findings suggest higher levels of network connectivity may increase the risk of becoming infected or that parasites influence lizard behaviour and consequently their position in the network. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau and R. James).  相似文献   
6.
A detailed analysis of international trends in air pollution control and waste management markets forecasts considerable growth and expansion due to increased economic activity, more stringent regulations requiring pollution control, and the increased amounts of solid waste being generated worldwide.  相似文献   
7.
Recent studies suggest that host origin databases for bacterial source tracking (BST) must contain a large number of isolates because bacterial subspecies change with geography and time. A new targeted sampling protocol was developed as a prelude to BST to minimize these changes. The research was conducted on the Sapelo River, a tidal river on the Georgia coast. A general sampling of the river showed fecal enterococcal numbers ranging from <10 (below the limit of detection) to 990 colony-forming units (CFU) per 100 mL. Locations with high enterococcal numbers were combined with local knowledge to determine targeted sampling sites. Fecal enterococcal numbers around one site ranged from <10 to 24,000 CFU per 100 mL. Bacterial source tracking was conducted to determine if a wastewater treatment facility at the site was responsible for this contamination. The fecal indicator bacterium was Enterococcus faecalis. Ribotyping, automated with a RiboPrinter (DuPont Qualicon, Wilmington, DE), was the BST method. Thirty-seven ribotypes were observed among 83 Ent. faecalis isolates obtained from the Sapelo River and the wastewater lagoon. Sixteen ribotypes were associated with either the river or the lagoon, and only five ribotypes (14%) were shared. Nevertheless, these five ribotypes represented 39 of the 83 Ent. faecalis isolates, almost a majority (47%). These results suggest that the fecal contamination in the river came from the wastewater treatment facility. As a prelude to BST, targeted sampling minimized subspecies changes with geography and time, and eliminated the need for a permanent host origin database by restricting BST to a small geographic area and requiring sampling to be completed in one day.  相似文献   
8.
9.
The southeastern United States supports one of two large loggerhead turtle (Caretta caretta) nesting aggregations worldwide and is therefore critical to global conservation and recovery efforts for the species. Previous studies have established the presence of four demographically distinct nesting populations (management units) corresponding to beaches from (1) North Carolina through northeastern Florida, (2) peninsular Florida, (3) the Dry Tortugas, and (4) northwest Florida. Temporal and geographic genetic structure of the nesting aggregation was examined utilizing partial mitochondrial control region haplotype frequencies from 834 samples collected over the 2002 through 2008 nesting seasons from 19 beaches as well as previously published haplotype data. Most rookeries did not exhibit interannual genetic variation. However, the interannual variation detected did significantly impact the interpretation of spatial genetic structure in northeastern Florida. Based on pairwise F ST comparisons, exact tests of population differentiation, and analysis of molecular variance, the present study upholds the distinctiveness of the four currently recognized management units and further supports recognition of discrete central eastern, southern (southeastern and southwestern), and central western Florida management units. Further subdivision may be warranted, but more intensive genetic sampling is required. In addition, tools such as telemetry and mark-recapture are needed to complement genetic data and overcome limitations of genetic markers in resolving loggerhead turtle rookery connectivity in the southeastern USA.  相似文献   
10.
An iron hydroxide floc is used as treatment for adsorbing low amounts of actinides during nuclear fuel re-processing. This waste is cemented only after pre-treatment with Ca(OH)(2). Characterisation of all simulant material has been undertaken using XRD, TGA and SEM/EDS. The floc is a moderately alkaline colloidal slurry containing approximately 15wt% solids, with the main particulate being an amorphous hydrated iron oxide. The main phase formed during pre-treatment appears to be an X-ray amorphous hydrated calcium-ferrate phase. Embedded within this are small amounts of crystalline Ca(OH)(2), calcite, Fe(6)(OH)(12)(CO(3)), Ca(6)Fe(2)(SO(4))(3)(OH)(12).26H(2)O and Ca(3)B(2)O(6), and can form depending on concentrations of Ca(OH)(2) and time. Apart from Ca(OH)(2) and calcite, none of the crystalline phases detected during pre-treatment are detected when the floc is encapsulated in an OPC/PFA composite cement hydrated for 90 days. The main crystalline phase detected in the hardened wasteform is a solid solution hydrogarnet, Ca(3)AlFe(SiO(4))(OH)(8), known as C(3)(A,F)SH(4) in cement chemistry nomenclature.  相似文献   
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