Part I. Application of the Fabry-Perot interferometer for high resolution studies Part II. Hyperfine structure in bromine

PART I: The Fabry-Perot interferometer is generally used in transmission. It is described how it can be modified so that the fringes can be used in reflection. The general theory of the reflection fringes is considered. It is shown that the interferometer used in reflection is about 30 times faster in light speed than one used intransmission. It is shown how the technique can beadopted to the measurement of wavelengths and to the evaluation of the line-widths of lines from weak sources. PART II: Hyperfine structure examinations are carried out over the range 6000 to 3700 in the arc spectrum of bromine and over the range 5500 to 3900 in the spark spectrum of bromine. Twenty-one lines in the arc spectrum of bromine are examined. Eighteen classified and twenty unclassified lines in Br II spectrum are measured for the first time and hyperfine structure term interval factors are derived for fourteen terms in thespark spectrum of bromine. The theory of the hyperfine structure analysis is considered in brief. Both the arc and the spark spectra are obtained by employing a circulating system and a high frequency oscillator. The analysis of the lines fits well the term scheme. A few anomalies have been noted and have been accounted for, some of them being due to faulty interpretations of the lines by previous workers. Deviations from the interval rule occur in the arc spectrum of bromine and these are completely explained by the existence of an electrical quadrupole moment of nuclei for both the bromine isotopes. The coupling constants for the terms concerned are determined from the term values and using these, both the quadrupole moment and the magnetic moment of the bromine nucleus are evaluated.<p

This is My Story: participatory performance for HIV and AIDS education at the University of Malawi

University students represent a subset of young men and women at risk for HIV in high prevalence settings. Innovative programs are needed to raise awareness on the unique issues around HIV and AIDS in the university campus, while training student leaders for peer-based education. The Process and Collaboration for Empowerment and Discussion (PACED) method engages artists and people living with HIV and AIDS (PLWHA) to create a performance that encourages community dialog about HIV and AIDS and empowers PLWHA. 'This is My Story' was a program at the University of Malawi, Chancellor College, which adapted the PACED approach for university students. A qualitative evaluation conducted 1 year later among students and PLWHA participants and audience members demonstrated retention of the following themes: (i) trust in a relationship and how it affects women,(ii) equality for PLWHA and (iii) life after HIV and AIDS. All of the PLWHA and 90.9% of student participants reported a greater sense of empowerment. Of the audience members, 82.1% discussed the performance with friends and family. We thus present the PACED approach as a valuable tool in HIV and AIDS education and prevention among university students in Malawi

An analysis of referrals to a level 3 intensive care unit in a resource-limited setting in South Africa

Background. With a shortage of intensive care unit (ICU) beds and rising healthcare costs in resource-limited settings, clinicians need to appropriately triage admissions into ICU to avoid wasteful expenditure and unnecessary bed utilisation. Objective. To assess the nature, appropriateness and outcome of referrals to a tertiary centre ICU. Methods. A retrospective review of ICU consults from September 2016 to February 2017 at King Edward VIII Hospital was performed. The study was approved by the University of KwaZulu-Natal Biomedical Research Ethics Committee (BE291/17). Data pertaining to patients’ demographics, referring doctor, diagnosis, comorbidities as well as biochemical and haemodynamic parameters were extracted. This information was then cross- referenced to the outcome of the ICU consultation. Data were descriptively analysed. Results. Five hundred consultations were reviewed over a 6-month period; 52.2% of patients were male and the mean age was 44 years. Junior medical officers referred 164 (32.8%) of the consultations. Although specialist supervision was available in 459 cases, it was only utilised in 339 (73.9%) of these cases. Most referrals were from tertiary (46.8%) or regional (30.4%) hospitals; however, direct referrals from district hospitals and clinics accounted for 20.4% and 1.4% of consultations, respectively. The appropriate referral pathway was not followed in 81 (16.2%) consultations. Forty-five percent of consults were accepted; however, 9.3% of these patients died before arrival in ICU. A total of 151 (30.2%) patients were refused ICU admission, with the majority (57%) of these owing to futility. Patients were unstable at the time of consult in 53.2% of referrals and 34.4% of consults had missing data. Conclusion. Critically ill patients are often referred by junior doctors without senior consultation, and directly from low-level healthcare facilities. A large proportion of ICU referrals are deemed futile and, of the patients accepted for admission, almost 1 in 10 dies prior to ICU admission. More emphasis needs to be placed on the training of doctors to appropriately triage and manage critically ill patients and ensure appropriate ICU referral and optimising of patient outcomes

Contact investigation for active tuberculosis among child contacts in Uganda.

BACKGROUND: Tuberculosis is a large source of morbidity and mortality among children. However, limited studies characterize childhood tuberculosis disease, and contact investigation is rarely implemented in high-burden settings. In one of the largest pediatric tuberculosis contact investigation studies in a resource-limited setting, we assessed the yield of contact tracing on childhood tuberculosis and indicators for disease progression in Uganda. METHODS: Child contacts aged &lt;15 years in Kampala, Uganda, were enrolled from July 2002 to June 2009 and evaluated for tuberculosis disease via clinical, radiographic, and laboratory methods for up to 24 months. RESULTS: Seven hundred sixty-one child contacts were included in the analysis. Prevalence of tuberculosis in our child population was 10%, of which 71% were culture-confirmed positive. There were no cases of disseminated tuberculosis, and 483 of 490 children (99%) started on isoniazid preventative therapy did not develop disease. Multivariable testing suggested risk factors including human immunodeficiency virus (HIV) status (odds ratio [OR], 7.90; P &lt; .001), and baseline positive tuberculin skin test (OR, 2.21; P = .03); BCG vaccination was particularly protective, especially among children aged ≤5 years (OR, 0.23; P &lt; .001). Adult index characteristics such as sex, HIV status, and extent or severity of disease were not associated with childhood disease. CONCLUSIONS: Contact tracing for children in high-burden settings is able to identify a large percentage of culture-confirmed positive tuberculosis cases before dissemination of disease, while suggesting factors for disease progression to identify who may benefit from targeted screening

Modelling subject-specific childhood growth using linear mixed-effect models with cubic regression splines.

Childhood growth is a cornerstone of pediatric research. Statistical models need to consider individual trajectories to adequately describe growth outcomes. Specifically, well-defined longitudinal models are essential to characterize both population and subject-specific growth. Linear mixed-effect models with cubic regression splines can account for the nonlinearity of growth curves and provide reasonable estimators of population and subject-specific growth, velocity and acceleration.We provide a stepwise approach that builds from simple to complex models, and account for the intrinsic complexity of the data. We start with standard cubic splines regression models and build up to a model that includes subject-specific random intercepts and slopes and residual autocorrelation. We then compared cubic regression splines vis-à-vis linear piecewise splines, and with varying number of knots and positions. Statistical code is provided to ensure reproducibility and improve dissemination of methods. Models are applied to longitudinal height measurements in a cohort of 215 Peruvian children followed from birth until their fourth year of life.Unexplained variability, as measured by the variance of the regression model, was reduced from 7.34 when using ordinary least squares to 0.81 (p < 0.001) when using a linear mixed-effect models with random slopes and a first order continuous autoregressive error term. There was substantial heterogeneity in both the intercept (p < 0.001) and slopes (p < 0.001) of the individual growth trajectories. We also identified important serial correlation within the structure of the data (ρ = 0.66; 95 % CI 0.64 to 0.68; p < 0.001), which we modeled with a first order continuous autoregressive error term as evidenced by the variogram of the residuals and by a lack of association among residuals. The final model provides a parametric linear regression equation for both estimation and prediction of population- and individual-level growth in height. We show that cubic regression splines are superior to linear regression splines for the case of a small number of knots in both estimation and prediction with the full linear mixed effect model (AIC 19,352 vs. 19,598, respectively). While the regression parameters are more complex to interpret in the former, we argue that inference for any problem depends more on the estimated curve or differences in curves rather than the coefficients. Moreover, use of cubic regression splines provides biological meaningful growth velocity and acceleration curves despite increased complexity in coefficient interpretation.Through this stepwise approach, we provide a set of tools to model longitudinal childhood data for non-statisticians using linear mixed-effect models

Gathering opinion leader data for a tailored implementation intervention in secondary healthcare: a randomised trial

Background: Health professionals’ behaviour is a key component in compliance with evidence-based recommendations. Opinion leaders are an oft-used method of influencing such behaviours in implementation studies, but reliably and cost effectively identifying them is not straightforward. Survey and questionnaire based data collection methods have potential and carefully chosen items can – in theory – both aid identification of opinion leaders and help in the design of an implementation strategy itself. This study compares two methods of identifying opinion leaders for behaviour-change interventions. Methods: Healthcare professionals working in a single UK mental health NHS Foundation Trust were randomly allocated to one of two questionnaires. The first, slightly longer questionnaire, asked for multiple nominations of opinion leaders, with specific information about the nature of the relationship with each nominee. The second, shorter version, asked simply for a list of named “champions” but no more additional information. We compared, using Chi Square statistics, both the questionnaire response rates and the number of health professionals likely to be influenced by the opinion leaders (i.e. the “coverage” rates) for both questionnaire conditions. Results: Both questionnaire versions had low response rates: only 15% of health professionals named colleagues in the longer questionnaire and 13% in the shorter version. The opinion leaders identified by both methods had a low number of contacts (range of coverage, 2–6 each). There were no significant differences in response rates or coverage between the two identification methods. Conclusions: The low response and population coverage rates for both questionnaire versions suggest that alternative methods of identifying opinion leaders for implementation studies may be more effective. Future research should seek to identify and evaluate alternative, non-questionnaire based, methods of identifying opinion leaders in order to maximise their potential in organisational behaviour change interventions

Antimetastatic Effects of Phyllanthus on Human Lung (A549) and Breast (MCF-7) Cancer Cell Lines

BACKGROUND: Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells. METHODOLOGY/PRINCIPAL FINDINGS: Cytotoxicity of Phyllanthus plant extracts were first screened using the MTS reduction assay. They were shown to inhibit MCF-7 (breast carcinoma) and A549 (lung carcinoma) cells growth with IC(50) values ranging from 50-180 µg/ml and 65-470 µg/ml for methanolic and aqueous extracts respectively. In comparison, they have lower toxicity on normal cells with the cell viability percentage remaining above 50% when treated up to 1000 µg/ml for both extracts. After determining the non-toxic effective dose, several antimetastasis assays were carried out and Phyllanthus extracts were shown to effectively reduce invasion, migration, and adhesion of both MCF-7 and A549 cells in a dose-dependent manner, at concentrations ranging from 20-200 µg/ml for methanolic extracts and 50-500 µg/ml for aqueous extracts. This was followed by an evaluation of the possible modes of cell death that occurred along with the antimetastatic activity. Phyllanthus was shown to be capable of inducing apoptosis in conjunction with its antimetastastic action, with more than three fold increase of caspases-3 and -7, the presence of DNA-fragmentation and TUNEL-positive cells. The ability of Phyllanthus to exert antimetastatic activities is mostly associated to the presence of polyphenol compounds in its extracts. CONCLUSIONS/SIGNIFICANCE: The presence of polyphenol compounds in the Phyllanthus plant is critically important in the inhibition of the invasion, migration, and adhesion of cancer cells, along with the involvement of apoptosis induction. Hence, Phyllanthus could be a valuable candidate in the treatment of metastatic cancers

Clinical standards for drug-susceptible TB in children and adolescents.

BACKGROUND: These clinical standards aim to provide guidance for diagnosis, treatment, and management of drug-susceptible TB in children and adolescents.METHODS: Fifty-two global experts in paediatric TB participated in a Delphi consensus process. After eight rounds of revisions, 51/52 (98%) participants endorsed the final document.RESULTS: Eight standards were identified: Standard 1, Age and developmental stage are critical considerations in the assessment and management of TB; Standard 2, Children and adolescents with symptoms and signs of TB disease should undergo prompt evaluation, and diagnosis and treatment initiation should not depend on microbiological confirmation; Standard 3, Treatment initiation is particularly urgent in children and adolescents with presumptive TB meningitis and disseminated (miliary) TB; Standard 4, Children and adolescents should be treated with an appropriate weight-based regimen; Standard 5, Treating TB infection (TBI) is important to prevent disease; Standard 6, Children and adolescents should receive home-based/community-based treatment support whenever possible; Standard 7, Children, adolescents, and their families should be provided age-appropriate support to optimise engagement in care and clinical outcomes; and Standard 8, Case reporting and contact tracing should be conducted for each child and adolescent.CONCLUSION: These consensus-based clinical standards, which should be adapted to local contexts, will improve the care of children and adolescents affected by TB

Clinical standards for drug-susceptible TB in children and adolescents

BACKGROUND: These clinical standards aim to provide guidance for diagnosis, treatment, and management of drug-susceptible TB in children and adolescents. METHODS: Fifty-two global experts in paediatric TB participated in a Delphi consensus process. After eight rounds of revisions, 51/52 (98%) participants endorsed the final document. RESULTS: Eight standards were identified: Standard 1, Age and developmental stage are critical considerations in the assessment and management of TB; Standard 2, Children and adolescents with symptoms and signs of TB disease should undergo prompt evaluation, and diagnosis and treatment initiation should not depend on microbiological confirmation; Standard 3, Treatment initiation is particularly urgent in children and adolescents with presumptive TB meningitis and disseminated (miliary) TB; Standard 4, Children and adolescents should be treated with an appropriate weight-based regimen; Standard 5, Treating TB infection (TBI) is important to prevent disease; Standard 6, Children and adolescents should receive home-based/community-based treatment support whenever possible; Standard 7, Children, adolescents, and their families should be provided age-appropriate support to optimise engagement in care and clinical outcomes; and Standard 8, Case reporting and contact tracing should be conducted for each child and adolescent. CONCLUSION: These consensus-based clinical standards, which should be adapted to local contexts, will improve the care of children and adolescents affected by TB.National Institutes of HealthRevisión por pare