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1.
Nelson A  Chomitz KM 《PloS one》2011,6(8):e22722
Protected areas (PAs) cover a quarter of the tropical forest estate. Yet there is debate over the effectiveness of PAs in reducing deforestation, especially when local people have rights to use the forest. A key analytic problem is the likely placement of PAs on marginal lands with low pressure for deforestation, biasing comparisons between protected and unprotected areas. Using matching techniques to control for this bias, this paper analyzes the global tropical forest biome using forest fires as a high resolution proxy for deforestation; disaggregates impacts by remoteness, a proxy for deforestation pressure; and compares strictly protected vs. multiple use PAs vs indigenous areas. Fire activity was overlaid on a 1 km map of tropical forest extent in 2000; land use change was inferred for any point experiencing one or more fires. Sampled points in pre-2000 PAs were matched with randomly selected never-protected points in the same country. Matching criteria included distance to road network, distance to major cities, elevation and slope, and rainfall. In Latin America and Asia, strict PAs substantially reduced fire incidence, but multi-use PAs were even more effective. In Latin America, where there is data on indigenous areas, these areas reduce forest fire incidence by 16 percentage points, over two and a half times as much as naïve (unmatched) comparison with unprotected areas would suggest. In Africa, more recently established strict PAs appear to be effective, but multi-use tropical forest protected areas yield few sample points, and their impacts are not robustly estimated. These results suggest that forest protection can contribute both to biodiversity conservation and CO2 mitigation goals, with particular relevance to the REDD agenda. Encouragingly, indigenous areas and multi-use protected areas can help to accomplish these goals, suggesting some compatibility between global environmental goals and support for local livelihoods.  相似文献   
2.
Objectives: We examined the relationship between comprehensive fitness tests and overweight using a school surveillance system in a racially diverse city in the United States. Research Methods and Procedures: Trained physical education teachers measured weight, height, and fitness annually from 2001 to 2003. We compiled data for a cross‐sectional analysis (11, 845 measurements on 6297 students, 5 to14 years of age) and a 1‐year prospective analysis (4215 measurements on 2927 students not overweight at baseline, 5 to 13 years of age). Overweight was defined as a BMI ≥95th percentile (Centers for Disease Control and Prevention 2000 growth charts), and underfit was defined as failing at least one of five fitness tests: endurance run, abdominal strength, flexibility, upper body strength, and agility (Amateur Athletic Union and Fitnessgram). Associations between fitness and overweight were examined using multivariate logistic regression models, adjusting for sociodemographic status and repeated measurements over time. Results: The mean number of fitness tests passed was lower among students with a BMI above the 80th percentile. Overweight incidence over 1 year was 7% and 2% for underfit and fit girls, respectively (odds ratio, 3.3; 95% confidence interval, 2.0 to 5.6). Not passing either the endurance run or upper body strength test was associated with overweight incidence in both boys and girls. After adjusting for baseline BMI, the endurance run remained a significant predictor of incident overweight among girls (odds ratio, 2.0; 95% confidence interval, 1.1 to 3.5). Discussion: Findings support a cross‐sectional inverse relationship between physical fitness and overweight among school‐aged children. The direction of causation between fitness and overweight is not clearly established and merits further study.  相似文献   
3.
Involvement of rabphilin-3A-like (RPH3AL), or Noc2, the potential effector of Ras-associated binding proteins Rab3A and Rab27A in the regulation of exocytotic processes in the endocrine pancreas has been demonstrated in experimental models. Noc2 expression together with other regulatory molecules of the exocytotic machinery in human tissues, however, has not been studied. We evaluated immunohistochemical expression of the key molecules of the exocytotic machinery, Noc2, Rab3A, Rab27A, and RIM2, together with the characteristic islet cell hormones, insulin and glucagon in normal and endocrine tumor tissues of human pancreas. Normal pancreatic islets were stained for all of these proteins and showed strong cytoplasmic localization. A similar pattern of strong cytoplasmic expression of these proteins was observed in the majority of endocrine tumors. By contrast, the exocrine portions of normal appearing pancreas completely lacked Rab27A staining and showed decreased expression of the proteins, Noc2, Rab3A, and RIM2. The staining pattern of Noc2 and Rab27A was similar to the staining pattern of glucagon-producing cells within the islets. The concomitant expression of Noc2 with these molecules suggests that Noc2 may serve as an effector for Rab3A and Rab27A and that it is involved in the regulation of exocytosis of the endocrine pancreas in humans.  相似文献   
4.
Bioluminescence in beetles is found mainly in the Elateroidea superfamily (Elateridae, Lampyridae and Phengodidae). The Neotropical region accounts for the richest diversity of bioluminescent species in the world with about 500 described species, most occurring in the Amazon, Atlantic rainforest and Cerrado (savanna) ecosystems in Brazil. The origin and evolution of bioluminescence, as well as the taxonomic status of several Neotropical taxa in these families remains unclear. In order to contribute to a better understanding of the phylogeny and evolution of bioluminescent Elateroidea we sequenced and analyzed sequences of mitochondrial NADH2 and the nuclear 28S genes and of the cloned luciferase sequences of Brazilian species belonging to the following genera: (Lampyridae) Macrolampis, Photuris, Amydetes, Bicellonycha, Aspisoma, Lucidota, Cratomorphus; (Elateridae) Conoderus, Pyrophorus, Hapsodrilus, Pyrearinus, Fulgeochlizus; and (Phengodidae) Pseudophengodes, Phrixothrix, Euryopa and Brasilocerus. Our study supports a closer phylogenetic relationship between Elateridae and Phengodidae as other molecular studies, in contrast with previous morphologic and molecular studies that clustered Lampyridae/Phengodidae. Molecular data also supported division of the Phengodinae subfamily into the tribes Phengodini and Mastinocerini. The position of the genus Amydetes supports the status of the Amydetinae as a subfamily. The genus Euryopa is included in the Mastinocerini tribe within the Phengodinae/Phengodidae. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
5.
The ability to discriminate between galactose and N- acetylgalactosamine, observed in some lectins, is crucial for their biological activity as well as their usefulness as tools in biology and medicine. However, the molecular basis of differential binding of lectins to these two sugars is poorly understood. Peanut agglutinin (PNA) is one of the few galactose-specific legume lectins which does not bind N- acetylgalactosamine at all and is, therefore, ideal for the study of the basis of specificity towards C-2 substituted derivatives of galactopyranosides. Examination of the three-dimensional structure of PNA in complex with lactose revealed the presence of both a longer loop and bulkier residues in the region surrounding the C-2 hydroxyl of the galactopyranoside ring, which can sterically prevent the accommodation of a bulky substituent in this position. One such residue, is a glutamic acid at position 129 which protrudes into the binding site and perhaps directly obstructs any substitution at the C-2 position. Two mutants in bacterially expressed PNA were therefore constructed. These were E129D and E129A, in which Glu129 was replaced by Asp and Ala, respectively. The specificity of the mutants for galactose, galactosamine, and N- acetylgalactosamine was examined through observing the inhibition of hemagglutination and binding of the lectin to immobilized asialofetuin. The results showed that the affinity of E129A and E129D for C-2-substituted derivatives of the galactose varies. The mutant E129D showed significant binding towards N- acetylgalactosamine, suggesting that the residue Glu 129 is crucial in imparting exclusive galactose-specificity upon PNA. This study not only attempts to provide an explanation for the inability of PNA to accommodate C-2-substituted derivatives at its primary subsite, but also seeks to present a basis for engineering lectins with altered specificities.   相似文献   
6.

Objective:

The purpose of this quasi‐experimental study was to examine the effect of a computerized point‐of‐care alert with clinical decision support on the rates of diagnosis of childhood obesity in a multisite group practice in Massachusetts; Cambridge Health Alliance (CHA) which implemented an alert, relative to a separate group practice, Harvard Vanguard Medical Associates (HVMA), that did not.

Design and Methods:

Height and weight data from 19,466 children of 2‐18 years with 34,908 well‐child care visits in CHA and 123,446 children with 282,271 visits in HVMA between 2006 and 2008 were collected. The alert and decision support tool was activated for CHA patients with an age‐ and sex‐specific body mass index of ≥95th percentile. The main outcome measure was documentation of an International Classification of Diseases, Ninth Revision [ICD‐9] code for obesity before and after implementation of the alert at CHA in 2007.

Results:

Among obese children, the adjusted rate of an ICD‐9 diagnosis of obesity increased from 2006‐2007 to 2008 significantly more at CHA than at HVMA (P < 0.001 for time‐by‐provider group interaction). In 2006‐2007, the rate of ICD‐9 diagnosis of obesity was significantly lower at CHA than at HVMA (adjusted odds ratio [OR]: 0.57; 95% confidence interval [CI]: 0.52‐0.62); but by 2008 was significantly higher at CHA than HVMA (adjusted OR: 1.25; 95% CI: 1.14‐1.38).

Conclusion:

A point‐of‐care alert was effective in improving obesity diagnosis in a multisite group practice, relative to a separate group practice that did not adopt an alert. Clinical decision support tools could help improve obesity diagnosis in pediatric primary care.  相似文献   
7.
Physical fitness is often inversely associated with adiposity in children cross-sectionally, but the effect of becoming fit or maintaining fitness over time on changes in weight status has not been well studied in children. We investigated the impact of changes in fitness over 1-4 years of follow-up on the maintenance or achievement of healthy weight among 2,793 schoolchildren who were first measured as 1st to 7th graders. Students were classified as "fit" or "underfit" according to age- and gender-specific norms in five fitness domains: endurance, agility, flexibility, upper body strength, and abdominal strength. Weight status was dichotomized by BMI percentile: "healthy weight" (<85th percentile) or "overweight/obese" (≥85th percentile). At baseline, of the 38.3% overweight/obese children, 81.9% (N = 875) were underfit. Underfit overweight students were more likely to achieve healthy weight if they achieved fitness (boys: odds ratio (OR) = 2.68, 95% confidence interval (CI) = 1.24-5.77; girls: OR = 4.67, 95%CI = 2.09-10.45). Initially fit overweight children (N = 194) were more likely to achieve healthy weight if they maintained fitness (boys: OR = 11.99, 95%CI = 2.18-65.89; girls: OR = 2.46, 95%CI = 1.04-5.83). Similarly, initially fit healthy-weight children (N = 717) were more likely to maintain healthy weight if they maintained fitness (boys: OR 3.70, 95%CI = 1.40-9.78; girls: OR = 4.14, 95%CI = 1.95-8.78). Overweight schoolchildren who achieve or maintain physical fitness are more likely to achieve healthy weight, and healthy-weight children who maintain fitness are more likely to maintain healthy weight. School-based policies/practices that support physical fitness may contribute to obesity reduction and maintenance of healthy weight among schoolchildren.  相似文献   
8.
9.
Aerobic fitness has been shown to have several beneficial effects on child health. However, research on its relationship with academic performance has been limited, particularly in developing countries and among undernourished populations. This study examined the association between aerobic fitness and academic achievement in clinically healthy but nutritionally compromised Indian school-aged children and assessed whether micronutrient status affects this association. 273 participants, aged 7 to 10.5 years, were enrolled from three primary schools in Bangalore, India. Data on participants’ aerobic fitness (20-m shuttle test), demographics, anthropometry, diet, physical activity, and micronutrient status were abstracted. School-wide exam scores in mathematics and Kannada language served as indicators of academic performance and were standardized by grade level. The strength of the fitness/achievement association was analyzed using Spearman’s rank correlation, multiple variable logistic regression, and multi-level models. Significant positive correlations between aerobic capacity (VO2 peak) and academic scores in math and Kannada were observed (P < 0.05). After standardizing scores across grade levels and adjusting for school, gender, socioeconomic status, and weight status (BMI Z-score), children with greater aerobic capacities (mL * kg-1 * min-1) had greater odds of scoring above average on math and Kannada exams (OR=1.08, 95% CI: 1.02 to 1.15 and OR=1.11, 95% CI: 1.04 to 1.18, respectively). This association remained significant after adjusting for micronutrient deficiencies. These findings provide preliminary evidence of a fitness/achievement association in Indian children. While the mechanisms by which aerobic fitness may be linked to academic achievement require further investigation, the results suggest that educators and policymakers should consider the adequacy of opportunities for physical activity and fitness in schools for both their physical and potential academic benefits.  相似文献   
10.

Background  

An early dispersal of biologically and behaviorally modern humans from their African origins to Australia, by at least 45 thousand years via southern Asia has been suggested by studies based on morphology, archaeology and genetics. However, mtDNA lineages sampled so far from south Asia, eastern Asia and Australasia show non-overlapping distributions of haplogroups within pan Eurasian M and N macrohaplogroups. Likewise, support from the archaeology is still ambiguous.  相似文献   
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