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51.
Anne E Smith Dana A Cavallo Tricia Dahl Ran Wu Tony P George Suchitra Krishnan-Sarin 《The Journal of adolescent health》2008,43(1):46-54
PURPOSE: Abstinence effects such as nicotine withdrawal and mood changes contribute to the maintenance of cigarette smoking in adult smokers, and emerging reports on adolescent smokers suggest they may experience similar subjective effects when deprived. This study aimed to prospectively document tobacco abstinence-induced changes during the first 48 hours of abstinence in adolescent smokers compared with nonsmokers, to distinguish effects distinct from typical adolescent lability. METHODS: Fifty-seven adolescent smokers and 44 adolescent nonsmokers were assessed during a 48-hour inpatient session. Characteristic nicotine withdrawal symptoms, cravings for cigarettes, and mood symptoms were measured at 13 time points following initiation of abstinence. RESULTS: The only abstinence-related effects observed were changes in craving for tobacco and feelings of anger. Tobacco craving increased and peaked quickly following initiation of abstinence and displayed a slight decrease toward the end of the 48-hour abstinence period, while anger symptoms peaked after a more prolonged abstinence. Overall, smokers' symptoms and cravings were positively associated with amount of daily smoking but not with reports of dependence or biological measures of extent of use. CONCLUSIONS: We observed that among adolescent smokers, the primary effects associated with abstinence from cigarettes are relatively minimal, and include a heightened and persistent craving to smoke and increases in anger. Although smokers had greater negative mood symptoms compared with nonsmokers, the presence and severity of most of these symptoms appear to be minimally altered by abstinence and not associated with dependency or biological indicators of amount of tobacco use. 相似文献
52.
Blythe A. Layton Devrim Kaya Christine Kelly Kenneth J. Williamson Dana Alegre Silke M. Bachhuber Peter G. Banwarth Jeffrey W. Bethel Katherine Carter Benjamin D. Dalziel Mark Dasenko Matthew Geniza Andrea George Anne-Marie Girard Roy Haggerty Kathryn A. Higley Denise M. Hynes Jane Lubchenco Katherine R. McLaughlin F. Javier Nieto Aslan Noakes Matthew Peterson Adriana D. Piemonti Justin L. Sanders Brett M. Tyler Tyler S. Radniecki 《Environmental health perspectives》2022,130(6)
Background: Positive correlations have been reported between wastewater SARS-CoV-2 concentrations and a community’s burden of infection, disease or both. However, previous studies mostly compared wastewater to clinical case counts or nonrepresentative convenience samples, limiting their quantitative potential.Objectives: This study examined whether wastewater SARS-CoV-2 concentrations could provide better estimations for SARS-CoV-2 community prevalence than reported cases of COVID-19. In addition, this study tested whether wastewater-based epidemiology methods could identify neighborhood-level COVID-19 hotspots and SARS-CoV-2 variants.Methods: Community SARS-CoV-2 prevalence was estimated from eight randomized door-to-door nasal swab sampling events in six Oregon communities of disparate size, location, and demography over a 10-month period. Simultaneously, wastewater SARS-CoV-2 concentrations were quantified at each community’s wastewater treatment plant and from 22 Newport, Oregon, neighborhoods. SARS-CoV-2 RNA was sequenced from all positive wastewater and nasal swab samples. Clinically reported case counts were obtained from the Oregon Health Authority.Results: Estimated community SARS-CoV-2 prevalence ranged from 8 to 1,687/10,000 persons. Community wastewater SARS-CoV-2 concentrations ranged from 2.9 to gene copies per liter. Wastewater SARS-CoV-2 concentrations were more highly correlated (Pearson’s ; ) with community prevalence than were clinically reported cases of COVID-19 (Pearson’s ; ). Monte Carlo simulations indicated that wastewater SARS-CoV-2 concentrations were significantly better than clinically reported cases at estimating prevalence (). In addition, wastewater analyses determined neighborhood-level COVID-19 hot spots and identified SARS-CoV-2 variants (B.1 and B.1.399) at the neighborhood and city scales.Discussion: The greater reliability of wastewater SARS-CoV-2 concentrations over clinically reported case counts was likely due to systematic biases that affect reported case counts, including variations in access to testing and underreporting of asymptomatic cases. With these advantages, combined with scalability and low costs, wastewater-based epidemiology can be a key component in public health surveillance of COVID-19 and other communicable infections. https://doi.org/10.1289/ EHP10289相似文献
53.
Peter ?alamún Marek Ren?o Eva Kucanová Tímea Brázová Ingrid Papajová Dana Miklisová Vladimíra Hanzelová 《Ecotoxicology (London, England)》2012,21(8):2319-2330
The effect of distance from a heavy metal pollution source on the soil nematode community was investigated on four sampling sites along an 4?km transect originating at the Kovohuty a.s. Krompachy (pollution source). The soil nematode communities were exposed to heavy metal influence directly and through soil properties changes. We quantified the relative effects of total and mobile fraction of metals (As, Cd, Cr, Cu, Pb, and Zn) on soil ecosystem using the nematode community structure (trophic and c-p groups,) and ecological indices (Richness of genera, H′, MI2-5, etc.). Pollution effects on the community structure of soil free living nematodes was found to be the highest near the pollution source, with relatively low population density and domination of insensitive taxa. A decrease in heavy metals contents along the transect was linked with an increase in complexity of nematode community. The majority of used indices (MI2-5, SI, H′) negatively correlated (P?<?0.05 or P?<?0.01) with heavy metals content and were sensitive to soil ecosystem disturbance. Contamination by heavy metals has negatively affected the soil environment, which resulted in nematode community structure and ecological indices changes. Results showed that the free-living nematodes are useful tools for bioindication of contamination and could be used as an alternative to the common approaches based on chemical methods. 相似文献
54.
Prenatal exposure to chlorpyrifos (CPF), an organophosphorus insecticide, has long been associated with delayed neurocognitive development and most recently with decrements in working memory at age 7. In the current paper, we expanded the previous work on CPF to investigate how additional biological and social environmental factors might create or explain differential neurodevelopmental susceptibility, focusing on main and moderating effects of the quality of the home environment (HOME) and child sex. We evaluate how the quality of the home environment (specifically, parental nurturance and environmental stimulation) and child sex interact with the adverse effects of prenatal CPF exposure on working memory at child age 7years. We did not observe a remediating effect of a high quality home environment (either parental nurturance or environmental stimulation) on the adverse effects of prenatal CPF exposure on working memory. However, we detected a borderline significant interaction between prenatal exposure to CPF and child sex (B (95% CI) for interaction term=-1.714 (-3.753 to 0.326)) suggesting males experience a greater decrement in working memory than females following prenatal CPF exposure. In addition, we detected a borderline interaction between parental nurturance and child sex (B (95% CI) for interaction term=1.490 (-0.518 to 3.499)) suggesting that, in terms of working memory, males benefit more from a nurturing environment than females. To our knowledge, this is the first investigation into factors that may inform an intervention strategy to reduce or reverse the cognitive deficits resulting from prenatal CPF exposure. 相似文献
55.
Aarthy Kannappan Dana T. Yip Nayna A. Lodhia John Morton James N. Lau 《Journal of Surgical Education》2012,69(6):798-801
There is considerable effort and time invested in providing feedback to medical students and residents during their time in training. However, little effort has been made to measure the effects of positive and negative verbal feedback on skills performance and motivation to learn and practice. To probe these questions, first-year medical students (n = 25) were recruited to perform a peg transfer task on Fundamentals of Laparoscopic Surgery box trainers. Time to completion and number of errors were recorded. The students were then randomized to receive either positive or negative verbal feedback from an expert in the field of laparoscopic surgery. After this delivery of feedback, the students repeated the peg transfer task. Differences in performance pre- and post-feedback and also between the groups who received positive feedback (PF) vs negative feedback (NF) were analyzed. A survey was then completed by all the participants. Baseline task times were similar between groups (PF 209.3 seconds; NF 203 seconds, p = 0.58). The PF group averaged 1.83 first-time errors while the NF group 1 (p = 0.84). Post-feedback task times were significantly decreased for both groups (PF 159.75 seconds, p = 0.05; NF 132.08 seconds, p = 0.002). While the NF group demonstrated a greater improvement in mean time than the PF group, this was not statistically significant. Both groups also made fewer errors (PF 0.33 errors, p = 0.04; NF 0.38 errors, p = 0.23). When surveyed about their responses to standardized feedback scenarios, the students stated that both positive and negative verbal feedback could be potent stimulants for improved performance and motivation. Further research is required to better understand the effects of feedback on learner motivation and the interpersonal dynamic between mentors and their trainees. 相似文献
56.
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58.
Dana Crowley Jack 《Health care for women international》2013,34(4):385-400
Sixty women's narratives about their anger were coded for elements of anger expression. Their decisions regarding how and where to express anger are most strongly influenced by the anticipated reactions of others. Six patterns of bringing anger into relationships or keeping it out were identified. Women bring anger into relationship: (1) positively and directly, with the goal of removing barriers to relationship; (2) aggressively, with the goal of hurting another; and (3) indirectly, through disguising anger with the goal of remaining safe from interpersonal consequences, using strategies of (a) quiet sabotage, (b) hostile distance, (c) deflection, and (d) loss of control. Women keep anger out of relationship (1) consciously and constructively, choosing to express it in positive ways; (2) explosively expressing anger, but not in the presence of another; and (3) through self-silencing, which ranges from conscious to lessconscious awareness of anger and its suppression. Implications of differing patterns for women's health are discussed. 相似文献
59.
Joanne M. Kwan Quan Guo Dana L. Kyluik‐Price Hongshen Ma Mark D. Scott 《American journal of hematology》2013,88(8):682-689
Microfluidic analysis of blood has potential clinical value for determining normal and abnormal erythrocyte deformability. To determine if a microfluidic device could reliably measure intra‐ and inter‐personal variations of normal and oxidized human red blood cell (RBC), venous blood samples were collected from repeat donors over time. RBC deformability was defined by the cortical tension (pN/µm), as determined from the threshold pressure required to deform RBC through 2–2.5 μm funnel‐shaped constrictions. Oxidized RBC were prepared by treatment with phenazine methosulphate (PMS; 50 µM). Analysis of the control and oxidized RBC demonstrated that the microfluidic device could clearly differentiate between normal and mildly oxidized (20.13 ± 1.47 versus 27.51 ± 3.64 pN/µm) RBC. In vivo murine studies further established that the PMS‐mediated loss of deformability correlated with premature clearance. Deformability variation within an individual over three independent samplings (over 21 days) demonstrated minimal changes in the mean pN/µm. Moreover, inter‐individual variation in mean control RBC deformability was similarly small (range: 19.37–21.40 pN/µm). In contrast, PMS‐oxidized cells demonstrated a greater inter‐individual range (range: 25.97–29.90 pN/µm) reflecting the differential oxidant sensitivity of an individual's RBC. Importantly, similar deformability profiles (mean and distribution width; 20.49 ± 1.67 pN/µm) were obtained from whole blood via finger prick sampling. These studies demonstrated that a low cost microfluidic device could be used to reproducibly discriminate between normal and oxidized RBC. Advanced microfluidic devices could be of clinical value in analyzing populations for hemoglobinopathies or in evaluating donor RBC products post‐storage to assess transfusion suitability. Am. J. Hematol. 88:682–689, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
60.
Media coverage of cervical cancer and the HPV vaccine: implications for geographic health inequities
Janice L. Krieger PhD Mira L. Katz PhD Dana Eisenberg MA Sarah Heaner MPH Melanie Sarge MA Parul Jain PhD 《Health expectations》2013,16(3):e1-e12
Objective To describe the content of newspaper articles about cervical cancer and the human papillomavirus (HPV) vaccine published in Appalachia and identify potential differences in coverage as compared to the content of newspaper articles published in non‐Appalachia Ohio. Background Individuals rely on media as an important source of health information. Inadequate coverage of health issues may reinforce health inequities such as the elevated cervical cancer incidence and mortality rates in Appalachia Ohio. Methods A content analysis was conducted of all newspaper articles about cervical cancer and the HPV vaccine published in Appalachia and non‐Appalachia Ohio during 2006. Findings A total of 121 published newspaper articles (42 in Appalachia and 79 in non‐Appalachia) about cervical cancer and the HPV vaccine were identified. Articles published in Appalachia Ohio were significantly less likely than articles published in non‐Appalachia Ohio to provide information about the threat of cervical cancer and the efficacy of the HPV vaccine. Specifically, few articles published in Appalachia included information about the ability of the vaccine to prevent cervical cancer, the cost of the vaccine and the availability of assistance programmes for the un‐ and underinsured. Conclusions Newspaper articles printed in the Appalachia region lacked vital information that could help promote uptake of the HPV vaccine. Health educators and healthcare providers should be aware that women from underserved geographic regions like Appalachia may have greater information needs regarding their risk of cervical cancer and the potential benefits of the HPV vaccine as compared to the general patient population. 相似文献