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1.
A potential association between socioeconomic status (SES) and self‐reported use of mobile phones has been investigated in a few studies. If measured exposure to mobile phone networks differs by SES in children, it has not yet been studied. Interview data of 1,481 children and 1,505 adolescents on participants' mobile phone use, socio‐demographic characteristics and potential confounders were taken from the German MobilEe‐study. Sociodemographic data was used to stratify participants into three “status groups” (low, middle, high). Using a personal dosimeter, we obtained an exposure profile over 24 h for each of the participants. Exposure levels during waking hours were expressed as mean percentage of the reference level. Children with a low SES were more likely to own a mobile phone (OR 2.1; 95% CI: 1.1–3.9) and also reported to use their mobile phone longer per day (OR 2.4; 95% CI: 1.1–5.4) than children with a high SES. For adolescents, self‐reported duration of mobile phone use per day was also higher with a low SES (OR: 3.4; 95% CI: 1.4–8.4) compared with a high SES. No association between SES and measured exposure to mobile telecommunication networks was seen for children or adolescents. Mobile phone use may differ between status groups with higher use among disadvantaged groups. However, this does not result in higher overall exposure to mobile telecommunication networks. Whether short duration of own mobile phone use or the small numbers of participants with a low SES are causal, have to be investigated in further studies. Bioelectromagnetics 31:20–27, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

2.
This study assessed the meaning of just‐about‐right (JAR) categories when used with a 5‐point intensity scale. The panelists comprised both consumer and in‐house respondents. The JAR categories have various meanings as perceived by the respondents: “prefer product,”“very good,”“I like the product,”“like it very much,”“highly favorable,”“high acceptability,”“desirable like the product,”“best for the situation” and “correct.” Thus, the JAR meanings invoke preference and acceptability. This article presents two additional analyses to help the product tested. One method of analysis divides below‐JAR deviation from the above‐JAR deviation, with standard statistical procedures applied in each data set. The second method introduces the signal‐to‐noise ratio statistic for analyzing the relation of JAR to overall liking. Both analytic methods provide new ways to look at the JAR data, especially with respect to hedonics and product improvement.  相似文献   

3.
4.
The impact that “Romanization” and the development of urban centers had on the health of the Romano‐British population is little understood. A re‐examination of the skeletal remains of 364 nonadults from the civitas capital at Roman Dorchester (Durnovaria) in Dorset was carried out to measure the health of the children living in this small urban area. The cemetery population was divided into two groups; the first buried their dead organized within an east–west alignment with possible Christian‐style graves, and the second with more varied “pagan” graves, aligned north–south. A higher prevalence of malnutrition and trauma was evident in the children from Dorchester than in any other published Romano‐British group, with levels similar to those seen in postmedieval industrial communities. Cribra orbitalia was present in 38.5% of the children, with rickets and/or scurvy at 11.2%. Twelve children displayed fractures of the ribs, with 50% of cases associated with rickets and/or scurvy, suggesting that rib fractures should be considered during the diagnosis of these conditions. The high prevalence of anemia, rickets, and scurvy in the Poundbury children, and especially the infants, indicates that this community may have adopted child‐rearing practices that involved fasting the newborn, a poor quality weaning diet, and swaddling, leading to general malnutrition and inadequate exposure to sunlight. The Pagan group showed no evidence of scurvy or rib fractures, indicating difference in religious and child‐rearing practices but that both burial groups were equally susceptible to rickets and anemia suggests a shared poor standard of living in this urban environment. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

5.
The aim of this work was the functional and proteomic analysis of a mutant, W3110 Bgl+/10, isolated from a batch culture of an Escherichia coli K‐12 strain maintained at room temperature without addition of nutrients for 10 years. When the mutant was evaluated in competition experiments in co‐culture with the wild‐type, it exhibited the growth advantage in stationary phase (GASP) phenotype. Proteomes of the GASP mutant and its parental strain were compared by using a 2DE coupled with MS approach. Several differentially expressed proteins were detected and many of them were successful identified by mass spectrometry. Identified expression‐changing proteins were grouped into three functional categories: metabolism, protein synthesis, chaperone and stress responsive proteins. Among them, the prevalence was ascribable to the “metabolism” group (72%) for the GASP mutant, and to “chaperones and stress responsive proteins” group for the parental strain (48%).  相似文献   

6.
We describe the first phosphoproteome of the model filamentous fungus Aspergillus nidulans. Phosphopeptides were enriched using titanium dioxide, separated using a convenient ultra‐long reverse phase gradient, and identified using a “high‐high” strategy (high mass accuracy on the parent and fragment ions) with higher‐energy collisional dissociation. Using this approach 1801 phosphosites, from 1637 unique phosphopeptides, were identified. Functional classification revealed phosphoproteins were overrepresented under GO categories related to fungal morphogenesis: “sites of polar growth,” “vesicle mediated transport,” and “cytoskeleton organization.” In these same GO categories, kinase‐substrate analysis of phosphoproteins revealed the majority were target substrates of CDK and CK2 kinase families, indicating these kinase families play a prominent role in fungal morphogenesis. Kinase‐substrate analysis also identified 57 substrates for kinases known to regulate secretion of hydrolytic enzymes (e.g. PkaA, SchA, and An‐Snf1). Altogether this data will serve as a benchmark that can be used to elucidate regulatory networks functionally associated with fungal morphogenesis and secretion. All MS data have been deposited in the ProteomeXchange with identifier PXD000715 ( http://proteomecentral.proteomexchange.org/dataset/PXD000715 ).  相似文献   

7.
Despite achievements in dolphin conservation for the tuna purse‐seine fishery of the eastern Pacific Ocean, debate continues about the magnitude and importance of dolphin mortality caused by small (unobserved) vessels. In‐port sampling of tuna catch size composition is a potentially cost‐effective means of identifying unobserved vessels that may be catching tunas associated with dolphins because yellowfin tuna caught in association with dolphins are larger, on average, than those caught in other types of purse‐seine sets. A classification algorithm to predict purse‐seine set type (“dolphin” vs. “nondolphin”) was built from port‐sampling data on yellowfin tuna length‐frequencies and the date and location of fishing of large (observed) vessels. This classification algorithm was used to screen the port‐sampling data of small vessels collected during 2006‐2009, assuming the fishing practices of the two groups resulted in similar catch characteristics. From these results, hypothetical time series of dolphin mortality for small vessels were constructed and incorporated into a population dynamics model, along with mortalities of large vessels. Results suggest that any dolphin mortality of small vessels is unlikely to be substantially affecting trends in dolphin abundance. These results underscore the importance of in‐port sampling, in combination with at‐sea observation and fishery‐independent surveys, to effective management.  相似文献   

8.
A subgroup of a population of Tursiops truncatus in southern Brazil is known for a cooperative behavior with artisanal fishermen whereby the dolphins shoal fish towards net‐casting fishermen. Combining photo‐identification data collected between September 2007 and 2009 with mark‐recapture and Pollock's robust design models, we assessed abundance within seasons and survival and temporary emigration rates of dolphins between seasons. We also reanalyzed a previous data set collected during 1989–1991, and Cormack‐Jolly‐Seber models were applied to estimate survival rates for each of the study periods. The abundance of marked “cooperative” dolphins varied between seasons from 18 (CI: 17–24) to 21 (CI: 20–24). The total abundance varied from 59 in the winter of 2008 (CI: 49–72) to 50 in the autumn of 2009 (CI: 40–62). The annual adult survival was estimated to be 0.917 (CI: 0.876–0.961), close to that estimated from data collected in the 1990s (0.941; CI: 0.888–0.998). The emigration probability was low (0.031; CI: 0.011–0.084) and different capture probabilities between the “cooperative” and “noncooperative” dolphins indicated a degree of behavioral segregation. The precision of our estimates is likely to provide sufficient power to detect population change, but we recommend a precautionary management approach to protect this vulnerable dolphin community and its unique cooperative feeding tradition.  相似文献   

9.
In this paper, we present a method that enable both homology-based approach and composition-based approach to further study the functional core (i.e., microbial core and gene core, correspondingly). In the proposed method, the identification of major functionality groups is achieved by generative topic modeling, which is able to extract useful information from unlabeled data. We first show that generative topic model can be used to model the taxon abundance information obtained by homology-based approach and study the microbial core. The model considers each sample as a “document,” which has a mixture of functional groups, while each functional group (also known as a “latent topic”) is a weight mixture of species. Therefore, estimating the generative topic model for taxon abundance data will uncover the distribution over latent functions (latent topic) in each sample. Second, we show that, generative topic model can also be used to study the genome-level composition of “N-mer” features (DNA subreads obtained by composition-based approaches). The model consider each genome as a mixture of latten genetic patterns (latent topics), while each functional pattern is a weighted mixture of the “N-mer” features, thus the existence of core genomes can be indicated by a set of common N-mer features. After studying the mutual information between latent topics and gene regions, we provide an explanation of the functional roles of uncovered latten genetic patterns. The experimental results demonstrate the effectiveness of proposed method.  相似文献   

10.
Nine healthy females were studied about the time of the spring equinox while living in student accommodations and aware of the passage of solar time. After 7 control days, during which a conventional lifestyle was lived under a 24h “constant routine,” the subjects lived 17 × 27h “days” (9h sleep in the dark and 18h wake using domestic lighting, if required). Throughout the experiment, recordings of wrist activity and rectal (core) temperature were taken. The raw temperature data were assessed for phase and amplitude by cosinor analysis and another method, “crossover times,” which does not assume that the data set is sinusoidal. Two different purification methods were used in attempts to remove the masking effects of sleep and activity from the core temperature record and so to measure more closely the endogenous component of this rhythm; these two methods were “purification by categories” and “purification by intercepts.” The former method assumes that the endogenous component is a sinusoid, and that the masking effects can be estimated by putting activity into a number of bands or categories. The latter method assumes that a temperature that would correspond to complete inactivity can be estimated from measured temperatures by linear regression of these on activity and extrapolation to a temperature at zero activity. Three indices were calculated to assess the extent to which exogenous effects had been removed from the temperature data by these purification methods. These indices were the daily variation of phase about its median value; the ratio of this variation to the daily deviation of phase about midactivity; and the relationship between amplitude and the square of the deviation of phase from midactivity. In all cases, the index would decrease in size as the contribution of the exogenous component to a data set fell. The purification by categories approach was successful in proportion to the number of activity categories that was used, and as few as four categories produced a data set with significantly less masking than raw data. The method purification by intercepts was less successful unless the raw data had been “corrected” to reflect the direct effects of sleep that were independent of activity (a method to achieve this being produced). Use of this purification method with the corrected data then gave results that showed least exogenous influences. Both this method and the purification by categories method with 16 categories of activity gave evidence that the exogenous component no longer made a significant contribution to the purified data set. The results were not significantly influenced by assessing amplitude and phase of the circadian rhythm from crossover times rather than cosinor analysis. The relative merits of the different methods, as well as of other published methods, are compared briefly; it is concluded that several purification methods, of differing degrees of sophistication and ease of application to raw data, are of value in field studies and other circumstances in which constant routines are not possible or are ethically undesirable. It is also concluded that such methods are often somewhat limited insofar as they are based on pragmatic or biological, rather than mathematical, considerations, and so it is desirable to attempt to develop models based equally on mathematics and biology. (Chronobiology International, 17(4), 539–566, 2000)  相似文献   

11.
The aim of this work was to study the exposure to magnetic fields of children living at different distances from a power line and to evaluate how well theoretical calculations compared with actual exposure. Personal exposure instruments were carried for 24 h by 65 schoolchildren living 28–325 m from a 300 kV transmission line; the current load was 200–700 A. About half of the children attended a school far from the power line, whereas the other half attended a school located about 25 m from the line. Exposure to magnetic fields was analyzed for three categories of location: at home, at school, and at all other places. Time spent in bed was analyzed separately. The results indicated that children who lived close to a power line had a higher magnetic field exposure than other children. The power line was the most important source of exposure when the magnetic field due to the line was greater than about 0.2 μT. Exposure at school influenced the 24 h time-weighted average results considerably in those cases where the distance between home and power line was very different from the distance between school and power line. The calculated magnetic field, based on line configuration, current load, and distance between home and power line, corresponded reasonably well with the measured field. However, the correlation depends on whether home only or 24 h exposure is used in the analysis and on which school the children attended. The calculated magnetic field seems to be a reasonably good predictor of actual exposure and could be used in epidemiological studies, at least in Norway, where the electrical system normally results in less ground current than in most other countries. Bioelectromagnetics 18:47–57, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

12.
13.
Ecological trait data are essential for understanding the broad‐scale distribution of biodiversity and its response to global change. For animals, diet represents a fundamental aspect of species’ evolutionary adaptations, ecological and functional roles, and trophic interactions. However, the importance of diet for macroevolutionary and macroecological dynamics remains little explored, partly because of the lack of comprehensive trait datasets. We compiled and evaluated a comprehensive global dataset of diet preferences of mammals (“MammalDIET”). Diet information was digitized from two global and cladewide data sources and errors of data entry by multiple data recorders were assessed. We then developed a hierarchical extrapolation procedure to fill‐in diet information for species with missing information. Missing data were extrapolated with information from other taxonomic levels (genus, other species within the same genus, or family) and this extrapolation was subsequently validated both internally (with a jack‐knife approach applied to the compiled species‐level diet data) and externally (using independent species‐level diet information from a comprehensive continentwide data source). Finally, we grouped mammal species into trophic levels and dietary guilds, and their species richness as well as their proportion of total richness were mapped at a global scale for those diet categories with good validation results. The success rate of correctly digitizing data was 94%, indicating that the consistency in data entry among multiple recorders was high. Data sources provided species‐level diet information for a total of 2033 species (38% of all 5364 terrestrial mammal species, based on the IUCN taxonomy). For the remaining 3331 species, diet information was mostly extrapolated from genus‐level diet information (48% of all terrestrial mammal species), and only rarely from other species within the same genus (6%) or from family level (8%). Internal and external validation showed that: (1) extrapolations were most reliable for primary food items; (2) several diet categories (“Animal”, “Mammal”, “Invertebrate”, “Plant”, “Seed”, “Fruit”, and “Leaf”) had high proportions of correctly predicted diet ranks; and (3) the potential of correctly extrapolating specific diet categories varied both within and among clades. Global maps of species richness and proportion showed congruence among trophic levels, but also substantial discrepancies between dietary guilds. MammalDIET provides a comprehensive, unique and freely available dataset on diet preferences for all terrestrial mammals worldwide. It enables broad‐scale analyses for specific trophic levels and dietary guilds, and a first assessment of trait conservatism in mammalian diet preferences at a global scale. The digitalization, extrapolation and validation procedures could be transferable to other trait data and taxa.  相似文献   

14.
Objective: The purpose of this study was to examine both cross‐sectional and longitudinal associations between frequency of family dinner and overweight status in a large sample of 9‐ to 14‐year‐old children. Research Methods and Procedures: We studied a cohort of 7784 girls and 6647 boys, 9 to 14 years of age at baseline in 1996, participating in the Growing Up Today Study. From annual mailed surveys, we calculated BMI from self‐reported height and weight and assessed frequency of family dinner over the previous year. We defined “overweight” as age‐ and sex‐specific BMI >85th percentile. We performed multiple logistic regression analyses; the longitudinal analyses assessed the association of previous year family dinner consumption with 1‐year incidence of becoming overweight, using prospective data from 1996 through 1999. Results: At baseline in 1996, 16% of participants had family dinner “never or some days,” 40% on “most days,” and 44% “every day.” Across these categories, overweight prevalence for girls was 19.4%, 16.6%, and 16.7% and for boys was 24.6%, 23.3%, and 22.7%, respectively. In cross‐sectional analyses, adjusting for potential confounders, the odds of being overweight was 0.85 [95% confidence interval (CI): 0.76, 0.96] among children who ate family dinner on “most days” or “every day” compared with those who ate family dinner “never or some days.” In longitudinal multivariate models, the odds ratios between previous year frequency of eating family dinner and 1‐year incidence of becoming overweight were 0.95 (95% CI: 0.78, 1.16) and 1.04 (95% CI: 0.85, 1.27) for children who ate family dinner on “most days” and “every day,” respectively, compared with those who ate family dinner “never or some days.” Discussion: The frequency of eating family dinner was inversely associated with overweight prevalence at baseline but not with likelihood of becoming overweight in longitudinal analyses.  相似文献   

15.
The molecular mechanisms by which gastric acid causes epithelial injury in the stomach and initiates an inflammatory reaction are poorly understood. We aimed in the present study to investigate the role of the early growth response gene Egr‐1 and ERK in gastric epithelial cells following acid exposure, and the signaling pathways involved. Western blotting was used to assess Egr‐1 protein levels in AGS cells. A quantitative measurement of acid‐induced Egr‐1 and ERK translocation was performed using a high content analysis approach. Egr‐1 functionality was assessed by transient transfection with Egr‐1 antisense oligonucleotide. Exposure of AGS cells to acidic conditions induced Egr‐1 protein expression in a pH‐ and time‐dependent manner. Egr‐1 expression was markedly increased as the pH was reduced from pH 7.4 to 6.4. High content analysis of Egr‐1 activation showed acid‐induced Egr‐1 nuclear translocation; a maximum observed at 1–2 h followed by a decline to basal levels beyond 4 h. Acidic pH also activated ERK1/2 phosphorylation, whereas ERK1/2 inhibitors PD98059 and U0216 blocked both acid‐induced Egr‐1 and ERK translocation and expression. Moreover, acid exposure up‐regulated VEGF expression, which was inhibited by the Egr‐1 antisense oligonucleotide. Our results also demonstrate that exposure to acid induces Egr‐1 via MEK‐ERK1/2 pathway. These data suggest that Egr‐1 activation might play a crucial role in gastric mucosal inflammation and associated epithelial injury. J. Cell. Biochem. 108: 249–260, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

16.

Objectives:

Eating behaviors and obesity are complex phenotypes influenced by genes and the environment, but few studies have investigated the interaction of these two variables. The purpose of this study was to use a gene‐environment interaction model to test for differences in children's food acceptance and body weights.

Design and Methods:

Inherited ability to taste 6‐n‐propylthiouracil (PROP) was assessed as a marker of oral taste responsiveness. Food environment was classified as “healthy” or “unhealthy” based on proximity to outlets that sell fruits/vegetables and fast foods using Geographic Information Systems (GIS). The cohort consisted of 120 children, ages 4‐6 years, recruited from New York City over 2005‐2010. Home address and other demographic variables were reported by parents and PROP status, food acceptance, and anthropometrics were assessed in the laboratory. Based on a screening test, children were classified as PROP tasters or non‐tasters. Hierarchical linear models analysis of variance was performed to examine differences in food acceptance and body mass index (BMI) z‐scores as a function of PROP status, the food environment (“healthy” vs. “unhealthy”), and their interaction.

Results and Conclusion:

Results showed an interaction between taster status and the food environment on BMI z‐score and food acceptance. Non‐taster children living in healthy food environments had greater acceptance of vegetables than taster children living in healthy food environments (P ≤ 0.005). Moreover, non‐tasters from unhealthy food environments had higher BMI z‐scores than all other groups (P ≤ 0.005). Incorporating genetic markers of taste into studies that assess the built environment may improve the ability of these measures to predict risk for obesity and eating behaviors. Obesity (2012)  相似文献   

17.
Adult human mesenchymal stem cells (MSCs) hold promise for an increasing list of therapeutic uses due to their ease of isolation, expansion, and multi‐lineage differentiation potential. To maximize the clinical potential of MSCs, the underlying mechanisms by which MSC functionality is controlled must be understood. We have taken a deconstructive approach to understand the individual components in vitro, namely the role of candidate “stemness” genes. Our recent microarray gene expression profiling data suggest that interleukin‐6 (IL‐6) may contribute to the maintenance of MSCs in their undifferentiated state. In this study, we showed that IL‐6 gene expression is significantly higher in undifferentiated MSCs as compared to their chondrogenic, osteogenic, and adipogenic derivatives. Moreover, we found that MSCs secrete copious amounts of IL‐6 protein, which decreases dramatically during osteogenic differentiation. We further evaluated the role of IL‐6 for maintenance of MSC “stemness,” using a series of functional assays. The data showed that IL‐6 is both necessary and sufficient for enhanced MSC proliferation, protects MSCs from apoptosis, inhibits adipogenic and chondrogenic differentiation of MSCs, and increases the rate of in vitro wound healing of MSCs. We further identified ERK1/2 activation as the key pathway through which IL‐6 regulates both MSC proliferation and inhibition of differentiation. Taken together, these findings show for the first time that IL‐6 maintains the proliferative and undifferentiated state of bone marrow‐derived MSCs, an important parameter for the optimization of both in vitro and in vivo manipulation of MSCs. J. Cell. Biochem. 108: 577–588, 2009. Published 2009 Wiley‐Liss, Inc.  相似文献   

18.
Abstract

The twenty-first century is marked with aggressive development of the wireless communications (satellite, mobile phones, Internet, Wi-Fi). In addition to thousand of satellites that deliver radio and TV signals, large satellite and base station networks secure intensive instant delivery of audio and video information. It is fair to say that that the entire civilization, both biosphere and mankind are exposed to continuous exposure of multitude of radiofrequency (RF) signals. It should be taken into account that the entire world population is exposed to exponentially increasing RF radiation from base stations and satellite antennas. While several years ago the potential hazard was connected with placement of mobile phones close to human head, today “smart phones” represent small, but powerful computers continuously receiving audio and video data. The largest group of users is the children and teenagers who “need” to communicate nearly 24?h a day. This is even more important because cell phones and tablets may be seen in the hands of children as little as two years in age. There is no way to assess and predict the potential damages of children brain, vision and hearing under exposure to RF radiation. The WHO precautionary principle and IARC classification must be applied in discussing the potential hazard of the use of today’s and tomorrow’s communication devices.  相似文献   

19.
Three‐arm noninferiority trials (involving an experimental treatment, a reference treatment, and a placebo)—called the “gold standard” noninferiority trials—are conducted in patients with mental disorders whenever feasible, but often fail to show superiority of the experimental treatment and/or the reference treatment over the placebo. One possible reason is that some of the patients receiving the placebo show apparent improvement in the clinical condition. An approach to addressing this problem is the use of the sequential parallel comparison design (SPCD). Nonetheless, the SPCD has not yet been discussed in relation to gold standard noninferiority trials. In this article, our aim was to develop a hypothesis‐testing method and its corresponding sample size calculation method for gold standard noninferiority trials with the SPCD. In a simulation, we show that the proposed hypothesis‐testing method achieves the nominal type I error rate and power and that the proposed sample size calculation method has adequate power accuracy.  相似文献   

20.
Chronic exposure to environmental stress may play a role in the development of obesity, through hyperactivation of the hypothalamic–pituitary–adrenocortical (HPA) axis. This study investigated the dynamics of weight gain and the activity of the HPA axis in women who developed weight gain after a stressful event. This is a case–control retrospective study. Two groups of age‐matched premenopausal women were selected. One (n = 14) included women characterized by a rapid weight gain following a stressful event, defined as the “stress‐related obesity” (SRO) group, and the other (n = 21) women with nonstress‐related development of obesity, defined as the “nonstress‐related obesity” (NSRO) group. Twenty‐one healthy premenopausal women served as normal‐weight controls. Baseline hormonal and metabolic parameters, and 24‐h urinary free cortisol (UFC/24 h) excretion rate (as a measure of HPA‐axis activity) were measured in all women. Anthropometry, diet, and physical activity were similar in both obese groups. Both obese groups showed similar metabolic and hormonal profiles, but the SRO group had UFC/24 h values (41.1 ± 14.3 µg) significantly higher (P < 0.001) with respect to the NSRO (26.6 ± 17.6 µg) or the normal‐weight control groups (21.1 ± 9.8 µg). Moreover, time (years) to achieve maximum Δweight gain (kg) and the Δweight gain/time ratio were significantly shorter (P < 0.001) and higher (P < 0.001) in the SRO group with respect to the NSRO group, respectively. In the SRO group, there was a tendency to a significant correlation between UFC/24 h and the Δweight gain/time ratio. These findings support the concept that SRO has distinct pathophysiological mechanisms, including hyperactivity of the HPA axis.  相似文献   

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