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Quality of Life Research - Researchers investigating person-centredness in older people’s long-term community care are hindered by the lack of appropriate measures. Studies have tended to...  相似文献   
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Background

South Africa is the first sub‐Saharan African country to legislate, fund and implement free preschool education. Human rights and restitution were at the forefront of the political struggle for democracy in South Africa. Levelling the playing fields by improving the school readiness of children disadvantaged by the racist policies of Apartheid is essential to the transformation of South African society.

Methods

A review of published and unpublished documents on Grade R was undertaken, and access and enrolment data come from the National Department of Basic Education's Education Management Information System (EMIS).

Results

A decade after initiation in 2005, 79% of 5‐year‐olds was enrolled in a preschool class; the vast majority of them in free public schools. Grade R is near universal and on track to becoming compulsory. It is part of the Foundation Phase (Grades 1–3) of schooling, falling under the Department of Basic Education, but also part of a broader national strategy to improve early child development under the direction of an Inter‐Departmental Steering. Evaluations demonstrate wide access to Grade R and high uptake, especially in the poorest areas. However, the quality of Grade R provision in these areas is not up to standard because of low levels of funding; inadequate training, supervision, remuneration and retention of Grade R teachers; insufficient learner support materials; and inadequate monitoring and quality assurance.

Conclusions

Lack of quality, amongst other factors, contributes to a widening school performance gap between children from more and less privileged areas. Quality of Grade R as well as earlier learning and subsequent years of schooling must be improved to achieve South Africa's aim to reduce poverty and inequality through, amongst others, parent and family involvement, learning in the home and preschool preparation.  相似文献   
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More than 500 abandoned uranium (U) mines within the Navajo Nation contribute U, arsenic (As) and other metals to groundwater, soil and potentially air through airborne transport. The adverse cardiovascular health effects attributed to cumulative exposure to these metals remains uncertain. The aim of this study was to examine whether environmental exposure to these metals may promote or exacerbate the oxidation of low-density lipoprotein (LDL) cholesterol in this Native American population. The correlation of cardiovascular biomarkers (oxidized LDL (oxLDL) and C-reactive protein (CRP)) from a Navajo cohort (n = 252) with mean annual As and U intakes from water and urine metals was estimated using linear regression. Proof-of-concept assays were performed to investigate whether As and U directly oxidize human LDL. Mean annual As intake from water was positively and significantly associated with oxLDL, but not CRP in this study population, while U intake estimates were negatively associated with oxLDL. In an acellular system, As, but not U, directly oxidized the apolipoprotein B-100 component of purified human LDL. Neither metal promoted lipid peroxidation of the LDL particle. Both the population and lab results are consistent with the hypothesis that As promotes oxidation of LDL, a crucial step in vascular inflammation and chronic vascular disease. Conversely, for outcomes related to U, negative associations were observed between U intake and oxLDL, and U only minimally altered human LDL in direct exposure experiments. Only urine U was correlated with CRP, whereas no other metals in water or urine were apparently reliable predictors of this inflammatory marker.  相似文献   
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BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients’ infection.  相似文献   
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