Managing peer relationships online - Investigating the use of Facebook by juvenile delinquents and youths-at-risk

10.1016/j.chb.2012.04.025Computers in Human Behavior2918-15CHBE

Grain Boundary Sliding Mechanisms in ZrN-Ag, ZrN-Au, and ZrN-Pd Nanocomposite Films

Nanocomposite films of ZrN-Me (Me = Ag, Au, or Pd) were produced by reactive unbalanced magnetron sputtering and were found to form a dense and homogeneous microstructure whereby nanocrystals of Me are distributed evenly throughout the ZrN matrix. Interestingly, the Young’s modulus was found to decrease much more dramatically with the increase in metal content for the ZrN-Ag system. A systematic ab initio study was undertaken to understand the mechanism of grain boundary sliding in these nanostructures. The maximum energy variation during the sliding was found to be the largest and the smallest for ZrN-Pd and ZrN-Ag, respectively

Study of Serum Lactate Dehydrogenase and Gamma-Glutamyl Transpeptidase in Breast Cancer Patients Receiving Chemotherapy.

Breast cancer (BC) is the most common type of cancer worldwide, being a major cause of morbidity in female. In Nepal it is the second most common type of cancer among females of perimenopausal age group. More than one quarter of the BC diagnosed in young Nepalese female, with familial history of breast cancer, early pregnancy, longer lactation and estrogen exposure and often with tumors showing aggressive biological behaviors. Anthracyclines (Doxorubicin) based treatment regime were reported to cause cardiotoxicity by increasing intramyocardial free radical production, lipid alterations and decreasing antioxidant level. Oxidative stress involving cellular reactive oxygen species (ROS) production is widely accepted mechanism but the molecular basis of chemotherapy induced organ toxicity remains highly controversial. An increased rate of metabolism and oxidative stress results rapid turnover of cancer cells that modulates the enzyme level in blood circulation. Serum LDH and GGT level correlates with tumor burden, metastatic character of BC and intensity of organtoxicity. The aim of our study is to evaluate the serum level of LDH and GGT in BC patients receiving chemotherapy and correlate these enzyme levels with different stages of BC. A total number of 150 subjects were included in the study, comprising 90 histopathologically confirmed 24 to 76 years aged patients of different breast cancer stages, receiving at least 3 cycles of 5-Fluorouracil, Adriamycin and Cyclophosphamide (FAC) chemotherapy. Sixty age- matched healthy women were enrolled as controls. Blood samples from each individual was collected after informed consent and analysed for serum LDH and GGT levels using standard biochemical methods. Data were analyzed using student's paired 't' test, Pearson correlation test and ANOVA. Serum LDH and GGT levels were significantly (p<0.001) increased in BC patients as compared to control group. When all 4 stages of BC were compared to control group, LDH and GGT showed steady and progressive increase in the activities of these enzymes from stage I-IV. The study concludes that serum LDH and GGT may be sensitive, specific and cost effective biomarkers in early diagnosis of breast cancer, assessing cancer prognosis and response to treatment

Work in Hypoxic Conditions-Consensus Statement of the Medical Commission of the Union Internationale des Associations d'Alpinisme (UIAA MedCom)

Objectives: The Commission gives recommendations on how to provide health and safety for employees in different kinds of low oxygen atmospheres. So far, no recommendations exist that take into account the several factors we have outlined in this report. Methods: The health and safety recommendations of several countries were analysed for their strength and deficiencies. The scientific literature was checked (Medline, etc.) and evaluated for relevance of the topic. Typical situations of work in hypoxia were defined and their specific risks described. Specific recommendations are provided for any of these situations. Results: We defined four main groups with some subgroups (main risk in brackets): short exposure (pressure change), limited exposure (acute altitude disease), expatriates (chronic altitude disease), and high-altitude populations (re-entry pulmonary oedema). For healthy unacclimatized persons, an acute but limited exposure down to 13% O2 does not cause a health risk. Employees should be advised to leave hypoxic areas for any break, if possible. Detailed advice is given for any other situation and pre-existing diseases. Conclusions: If the specific risk of the respective type of hypoxia is taken into account, a pragmatic approach to provide health and safety for employees is possible. In contrast to other occupational exposures, a repeated exposure as often as possible is of benefit as it causes partial acclimatization. The consensus statement was approved by written consent in lieu of a meeting in July 200

The STRATAA study protocol: a programme to assess the burden of enteric fever in Bangladesh, Malawi and Nepal using prospective population census, passive surveillance, serological studies and healthcare utilisation surveys.

Introduction Invasive infections caused by Salmonella enterica serovar Typhi and Paratyphi A are estimated to account for 12–27 million febrile illness episodes worldwide annually. Determining the true burden of typhoidal Salmonellae infections is hindered by lack of population-based studies and adequate laboratory diagnostics. The Strategic Typhoid alliance across Africa and Asia study takes a systematic approach to measuring the age-stratified burden of clinical and subclinical disease caused by typhoidal Salmonellae infections at three high-incidence urban sites in Africa and Asia. We aim to explore the natural history of Salmonella transmission in endemic settings, addressing key uncertainties relating to the epidemiology of enteric fever identified through mathematical models, and enabling optimisation of vaccine strategies. Methods/design Using census-defined denominator populations of ≥100 000 individuals at sites in Malawi, Bangladesh and Nepal, the primary outcome is to characterise the burden of enteric fever in these populations over a 24-month period. During passive surveillance, clinical and household data, and laboratory samples will be collected from febrile individuals. In parallel, healthcare utilisation and water, sanitation and hygiene surveys will be performed to characterise healthcare-seeking behaviour and assess potential routes of transmission. The rates of both undiagnosed and subclinical exposure to typhoidal Salmonellae (seroincidence), identification of chronic carriage and population seroprevalence of typhoid infection will be assessed through age-stratified serosurveys performed at each site. Secondary attack rates will be estimated among household contacts of acute enteric fever cases and possible chronic carriers. Ethics and dissemination This protocol has been ethically approved by the Oxford Tropical Research Ethics Committee, the icddr,b Institutional Review Board, the Malawian National Health Sciences Research Committee and College of Medicine Research Ethics Committee and Nepal Health Research Council. The study is being conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice. Informed consent was obtained before study enrolment. Results will be submitted to international peer-reviewed journals and presented at international conferences. Trial registration number ISRCTN 12131979. Ethics references Oxford (Oxford Tropical Research Ethics Committee 39-15). Bangladesh (icddr,b Institutional Review Board PR-15119). Malawi (National Health Sciences Research Committee 15/5/1599). Nepal (Nepal Health Research Council 306/2015)

A Bayesian approach for estimating typhoid fever incidence from large-scale facility-based passive surveillance data

Decisions about typhoid fever prevention and control are based on estimates of typhoid incidence and their uncertainty. Lack of specific clinical diagnostic criteria, poorly sensitive diagnostic tests, and scarcity of accurate and complete datasets contribute to difficulties in calculating age-specific population-level typhoid incidence. Using data from the Strategic Typhoid Alliance across Africa and Asia program, we integrated demographic censuses, healthcare utilization surveys, facility-based surveillance, and serological surveillance from Malawi, Nepal, and Bangladesh to account for under-detection of cases. We developed a Bayesian approach that adjusts the count of reported blood-culture-positive cases for blood culture detection, blood culture collection, and healthcare seeking—and how these factors vary by age—while combining information from prior published studies. We validated the model using simulated data. The ratio of observed to adjusted incidence rates was 7.7 (95% credible interval [CrI]: 6.0-12.4) in Malawi, 14.4 (95% CrI: 9.3-24.9) in Nepal, and 7.0 (95% CrI: 5.6-9.2) in Bangladesh. The probability of blood culture collection led to the largest adjustment in Malawi, while the probability of seeking healthcare contributed the most in Nepal and Bangladesh; adjustment factors varied by age. Adjusted incidence rates were within or below the seroincidence rate limits of typhoid infection. Estimates of blood-culture-confirmed typhoid fever without these adjustments results in considerable underestimation of the true incidence of typhoid fever. Our approach allows each phase of the reporting process to be synthesized to estimate the adjusted incidence of typhoid fever while correctly characterizing uncertainty, which can inform decision-making for typhoid prevention and control

High-throughput bacterial SNP typing identifies distinct clusters of Salmonella Typhi causing typhoid in Nepalese children.

BACKGROUND: Salmonella Typhi (S. Typhi) causes typhoid fever, which remains an important public health issue in many developing countries. Kathmandu, the capital of Nepal, is an area of high incidence and the pediatric population appears to be at high risk of exposure and infection. METHODS: We recently defined the population structure of S. Typhi, using new sequencing technologies to identify nearly 2,000 single nucleotide polymorphisms (SNPs) that can be used as unequivocal phylogenetic markers. Here we have used the GoldenGate (Illumina) platform to simultaneously type 1,500 of these SNPs in 62 S. Typhi isolates causing severe typhoid in children admitted to Patan Hospital in Kathmandu. RESULTS: Eight distinct S. Typhi haplotypes were identified during the 20-month study period, with 68% of isolates belonging to a subclone of the previously defined H58 S. Typhi. This subclone was closely associated with resistance to nalidixic acid, with all isolates from this group demonstrating a resistant phenotype and harbouring the same resistance-associated SNP in GyrA (Phe83). A secondary clone, comprising 19% of isolates, was observed only during the second half of the study. CONCLUSIONS: Our data demonstrate the utility of SNP typing for monitoring bacterial populations over a defined period in a single endemic setting. We provide evidence for genotype introduction and define a nalidixic acid resistant subclone of S. Typhi, which appears to be the dominant cause of severe pediatric typhoid in Kathmandu during the study period

Burden of enteric fever at three urban sites in Africa and Asia: a multicentre population-based study

Summary Background Enteric fever is a serious public health concern in many low-income and middle-income countries. Numerous data gaps exist concerning the epidemiology of Salmonella enterica serotype Typhi (S Typhi) and Salmonella enterica serotype Paratyphi (S Paratyphi), which are the causative agents of enteric fever. We aimed to determine the burden of enteric fever in three urban sites in Africa and Asia. Methods In this multicentre population-based study, we did a demographic census at three urban sites in Africa (Blantyre, Malawi) and Asia (Kathmandu, Nepal and Dhaka, Bangladesh) between June 1, 2016, and Sept 25, 2018. Households were selected randomly from the demographic census. Participants from within the geographical census area presenting to study health-care facilities were approached for recruitment if they had a history of fever for 72 h or more (later changed to >48 h) or temperature of 38·0°C or higher. Facility-based passive surveillance was done between Nov 11, 2016, and Dec 31, 2018, with blood-culture collection for febrile illness. We also did a community-based serological survey to obtain data on Vi-antibody defined infections. We calculated crude incidence for blood-culture-confirmed S Typhi and S Paratyphi infection, and calculated adjusted incidence and seroincidence of S Typhi blood-culture-confirmed infection. Findings 423 618 individuals were included in the demographic census, contributing 626 219 person-years of observation for febrile illness surveillance. 624 S Typhi and 108 S Paratyphi A isolates were collected from the blood of 12 082 febrile patients. Multidrug resistance was observed in 44% S Typhi isolates and fluoroquinolone resistance in 61% of S Typhi isolates. In Blantyre, the overall crude incidence of blood-culture confirmed S Typhi was 58 cases per 100 000 person-years of observation (95% CI 48–70); the adjusted incidence was 444 cases per 100 000 person-years of observation (95% credible interval [CrI] 347–717). The corresponding rates were 74 (95% CI 62–87) and 1062 (95% CrI 683–1839) in Kathmandu, and 161 (95% CI 145–179) and 1135 (95% CrI 898–1480) in Dhaka. S Paratyphi was not found in Blantyre; overall crude incidence of blood-culture-confirmed S Paratyphi A infection was 6 cases per 100 000 person-years of observation (95% CI 3–11) in Kathmandu and 42 (95% CI 34–52) in Dhaka. Seroconversion rates for S Typhi infection per 100 000 person-years estimated from anti-Vi seroconversion episodes in serological surveillance were 2505 episodes (95% CI 1605–3727) in Blantyre, 7631 (95% CI 5913–9691) in Kathmandu, and 3256 (95% CI 2432–4270) in Dhaka. Interpretation High disease incidence and rates of antimicrobial resistance were observed across three different transmission settings and thus necessitate multiple intervention strategies to achieve global control of these pathogens. Funding Wellcome Trust and the Bill & Melinda Gates Foundation