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This paper presents a low-profile multi-slotted patch antenna for long term evolution (LTE) and fifth-generation (5G) communication applications. The studied antenna comprised of a stepped patch and a ground plane. To attain the required operating band, three slots have been inserted within the patch. The insertion of the slots enhances the capacitive effect and helps the prototype antenna to achieve an operating band ranging from 3.15 to 5.55 GHz (S11 ≤−10 dB), covering the N77/N78/N79 for sub-6 GHz 5G wireless communications and LTE bands of 22/42/43/46. The wideband antenna presented in this paper offers omnidirectional stable radiation patterns, good gains, and efficiency with a compact size which make this design an ideal contender for wireless fidelity (WiFi), wireless local area network (WLAN), LTE, and sub-6 GHz 5G communication applications.
Child psychiatric service is a novel approach in Bangladesh but has proved its efficacy within a short time.
To describe how a developing country has established sustainable child psychiatric services by using limited resources effectively.
Discuss the service delivery model and recent achievements in child psychiatry in Bangladesh as well as the limitations and strengths.
Effective policy making, capacity building and community based survey are the turning point of the development of child psychiatry in Bangladesh. The prevalence of child mental disorders found 18.4% in a community based survey. By the efforts of few visionary psychiatrists the wing of child psychiatry has established in Bangabandhu Sheikh Mujib Medical University (BSMMU) and separate department named ‘Child Adolescent and Family Psychiatry’ has formed in National Institute of Mental Health (NIMH), Dhaka. Center for Neurodevelopment and Autism in Children (CNAC) also established in BSMMU with the mission to serve the children with neurodevelopmental disabilities, to increase awareness and to train the professionals. From 2008 the Child Guidance Clinic of national Institute of Mental Health Dhaka served more than three thousand children with any mental disorders.
According to the current scenario we can comment that the future prospect of child psychiatry in Bangladesh is promising. In spite of very limited resources the child psychiatry is going ahead to set an example for other developing countries in the context of sustainable service delivery model.
Bangladesh is a disaster prone country. According to one record during last 100 years, there had been 75 severe cyclones and floods in Bangladesh. On the other hand as many as 1200 kilometer of river banks are under active erosion in every year. The government of Bangladesh, nongovernmental organizations, members of the civil society, the health professionals – all of them have chalked out their programme embedded with economic relief and assistance. At best, some sort of medical aid in the form of medicine and physical treatment and recovery are extended to the affected people. The severity of mental and psychological trauma and casualties had always remained beyond their imagination. For the first time in the history of Bangladesh, multiple teams consisted of psychiatrists, psychologists, social workers and other support service staffs rushed to the Cyclone affected area to estimate the need for psychosocial care and for providing management on 2007. In 2013 a multistoried has collapsed in Bangladesh and died more than thousand peoples. Currently, the National Plan for Disaster Management 2010-2015 keeps no space for the people who ardently need post disaster psychosocial care. Consequently, the mental health care professionals are strongly lobbying for inclusion of post-disaster psychosocial rehabilitation service within the National Plan for Disaster Management. Mainstream health professionals specially the primary health care providers should be brought under coverage of a full-fledged training course on disaster psychiatry. In addition, infrastructure development and administrative reform is urgently required in this arena.
This article describes a CDI outbreak in a long-term care (LTC) facility that used molecular typing techniques and whole-genome sequencing to identify widespread dissemination of the clonal strain in the environment which was successfully removed after terminal cleaning.
This study was conducted in a long-term care facility in Texas.
A recently hospitalized LTC patient was diagnosed with CDI followed shortly thereafter by 7 subsequent CDI cases. A stool specimen was obtained from each patient for culturing and typing. An environmental point-prevalence study of the facility was conducted before and after terminal cleaning of the facility to assess environmental contamination. Cultured isolates were typed using ribotyping, multilocus variant analysis, and whole-genome sequencing.
Stool samples were available for 5 of 8 patients; of these specimens, 4 grew toxigenic C. difficile ribotype 027. Of 50 environmental swab samples collected throughout the facility prior to the facility-wide terminal cleaning, 19 (38%) grew toxigenic C. difficile (most commonly ribotype 027, 79%). The terminal cleaning was effective at reducing C. difficile spores in the environment and at eradicating the ribotype 027 strain (P<.001). Using multilocus variance analysis and whole-genome sequencing, clinical and environmental strains were highly related and, in some cases, were identical.
Using molecular typing techniques, we demonstrated reduced environmental contamination with toxigenic C. difficile and the eradication of a ribotype 027 clone. These techniques may help direct infection control efforts and decrease the burden of CDI in the healthcare system.
We conducted a longitudinal assessment in 466 underweight and 446 normal-weight children aged 6–24 months living in the urban slum of Dhaka, Bangladesh to determine the association between vitamin D and other micronutrient status with upper respiratory tract infection (URI) and acute lower respiratory infection (ALRI). Incidence rate ratios of URI and ALRI were estimated using multivariable generalized estimating equations. Our results indicate that underweight children with insufficient and deficient vitamin D status were associated with 20% and 23–25% reduced risk of URI, respectively, compared to children with sufficient status. Underweight children, those with serum retinol deficiency were at 1·8 [95% confidence interval (CI) 1·4–2·4] times higher risk of ALRI than those with retinol sufficiency. In normal-weight children there were no significant differences between different vitamin D status and the incidence of URI and ALRI. However, normal-weight children with zinc insufficiency and those that were serum retinol deficient had 1·2 (95% CI 1·0–1·5) times higher risk of URI and 1·9 (95% CI 1·4–2·6) times higher risk of ALRI, respectively. Thus, our results should encourage efforts to increase the intake of retinol-enriched food or supplementation in this population. However, the mechanisms through which vitamin D exerts beneficial effects on the incidence of childhood respiratory tract infection still needs further research.
Conflicting reports have been published on the association between Clostridium difficile ribotypes and severe disease outcomes in patients with C. difficile infection (CDI); several so-called hypervirulent ribotypes have been described. We performed a multicenter study to assess severe disease presentation and severe outcomes among CDI patients infected with different ribotypes.
Stool samples that tested positive for C. difficile toxin were collected and cultured from patients who presented to any of 7 different hospitals in Houston, Texas (2011–2013). C. difficile was characterized using a fluorescent PCR ribotyping method. Medical records were reviewed to determine clinical characteristics and ribotype association with severe CDI presentation (ie, leukocytosis and/or hypoalbuminemia) and severe CDI outcomes (ie, ICU admission, ileus, toxic megacolon, colectomy, and/or in-hospital death).
Our study included 715 patients aged 61±18 years (female: 63%; median Charlson comorbidity index: 2.5±2.4; hospital-onset CDI: 45%; severe CDI: 36.7%; severe CDI outcomes: 12.3%). The most common ribotypes were 027, 014-020, FP311, 002, 078-126, and 001. Ribotype 027 was a significant independent predictor of severe disease (adjusted odds ratio [aOR], 2.24; 95% confidence interval [CI], 1.53–3.29; P<.001) and severe CDI outcomes (aOR, 1.71; 95% CI, 1.02–2.85; P=.041) compared with all other ribotypes in aggregate. However, in an analysis using all common ribotypes as individual variables, ribotype 027 was not associated with severe CDI outcomes more often than other ribotypes.
Ribotype 027 showed virulence equal to that of other ribotypes identified in this endemic setting. Clinical severity markers of CDI may be more predictive of severe CDI outcomes than a particular ribotype.
Infect. Control Hosp. Epidemiol. 2015;36(11):1318–1323
High temperature solid state sodium (23Na) magic angle spinning (MAS) NMR spin lattice relaxation times (T1) were evaluated for a series of NASICON (Na3Zr2PSi2O12) materials to directly determine Na jump rates. Simulations of the T1 temperature variations that incorporated distributions in Na jump activation energies, or distribution of jump rates, improved the agreement with experiment. The 23Na NMR T1 relaxation results revealed that distributions in the Na dynamics were present for all of the NASICON materials investigated here. The 23Na relaxation experiments also showed that small differences in material composition and/or changes in the processing conditions impacted the distributions in the Na dynamics. The extent of the distribution was related to the presence of a disordered or glassy phosphate phase present in these different sol-gel processed materials. The 23Na NMR T1 relaxation experiments are a powerful tool to directly probing Na jump dynamics and provide additional molecular level details that could impact transport phenomena.
The study aimed to determine the geographical diversity in seasonality of major diarrhoeal pathogens among 21 138 patients enrolled between 2010 and 2012 in two urban and two rural sites in Bangladesh under the surveillance system of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b). Distinct patterns in seasonality were found for rotavirus diarrhoea which peaked in winter across the sites (December and January) and dipped during the rainy season (May) in urban Dhaka, August in Mirpur and July in Matlab, equated by time-series analysis using quasi-Poisson regression model. Significant seasonality for shigellosis was observed in Dhaka and rural Mirzapur. Cholera had robust seasonality in Dhaka and Matlab in the hot and rainy seasons. For enterotoxogenic Escherichia coli (ETEC) diarrhoea, clearly defined seasonality was observed in Dhaka (summer). Understanding the seasonality of such pathogens can improve case management with appropriate therapy, allowing policy-makers to identify periods of high disease burden.
Since its introduction in early 1990s, bulk-heterojunction organic photovoltaic solar cell (BHJ-OPV) has promised high-efficiency at ultra-low cost and weight, with potential for non-traditional applications such as building-integrated PV. There is a widespread presumption, however, that the complexity of morphology makes carrier transport in OPV irreducibly complicated, and possibly, beyond predictive modeling. In this paper, we use elementary and intuitive arguments to derive the fundamental thermodynamic as well as morphology-specific practical limits of BHJ-OPV efficiency. We find that constraints of the percolation threshold and trade-off among short-circuit current, open circuit voltage, and fill factor make substantial improvement in OPV efficiency difficult. We posit that future improvement in OPV will rely not on morphology engineering, or reducing the polymer bandgap, but on increasing both the effective μ × τ product and the cross-gap between donor/acceptors. Even if the OPV fails to achieve the highest efficiency anticipated by the thermodynamic limit, its novel form factor, lightweight, and transparency can make it a commercially viable option for many applications.
Maximizing power and energy densities of ultracapacitors requires configuring redox-active materials in specific architectures that: 1) maximize electrolyte-electrode contact area, 2) minimize transport distances for both electrons and charge compensating species, and 3) minimize transport barriers. We have developed a simple solution-based method, using an organic template, that enables us to introduce hierarchical porosity in ruthenium oxide down to the nano-scale by controlling the oxidative crystal growth of RuO2. The high capacitances of the resulting nanostructured electrodes were found to be comparable to hydrous ruthenium oxide formed under dramatically different conditions. Materials characterization reveals that the organic template directs structure formation and promotes hydroxyl retention.
Antibiotic resistance data, made available from laboratory records during eight cholera outbreaks between 1990 and 2004 showed Vibrio cholerae serogroup O1 to have a low level of resistance (2–3%) to tetracycline during 1990–1991. Resistance increased for tetracycline (95%), chloramphenicol (78%), doxycycline (70%) and trimethoprim–sulphamethoxazole (97%) in subsequent outbreaks. A significant drop in resistance to tetracycline and chloramphenicol followed the adoption of a national policy to replace tetracycline with erythromycin for treating cholera. Sixty-nine strains from cholera outbreaks in Zambia between 1996 and 2004, were examined for antibiotic resistance and basic molecular traits. A 140 MDa conjugative, multidrug-resistant plasmid was found to encode tetracycline resistance in strains from 1996/1997 whereas strains from 2003/2004 were resistant to furazolidone, but susceptible to tetracycline, and lacked this plasmid. PCR revealed 25 of 27 strains from 1996/1997 harboured the intl1 class 1 integron but lacked SXT, a conjugative transposon element. Similar screening of 42 strains from 2003/2004 revealed all carried SXT but not the intl1 class 1 integron. All 69 strains, except two, one lacking ctxA and the other rstR and thus presumably truncated in the CTX prophage region, were positive for important epidemic markers namely rfbO1, ctxA, rstR2, and tcpA of El Tor biotype. Effective cholera management is dependent on updated reports on culture and sensitivity to inform the choice of antibiotic. Since the emergence of antibiotic resistance may significantly influence strategies for controlling cholera, continuous monitoring of epidemic strains is crucial.
The response of germination and early seedling growth to levels of salinity (0, 50, 100, 150, 200 and 250 mM NaCl) were examined in single seed lots of ten modern rice genotypes. Unaged and deteriorated rice seeds were germinated in rolled paper towels and in Petri dishes. Initial seed quality, final germination, germination rate and early seedling growth were assessed. The samples of the rice genotypes differed in their initial seed quality (measured in terms of Ki). The effect of deterioration varied depending upon the initial seed quality and the severity of the treatment imposed. Ageing (using the technique of controlled deterioration, CD) for up to 24 h had no effect on final germination levels. Although CD for 30 h only reduced final germination slightly, ageing for 36 or 48 h reduced it greatly. Controlled deterioration for 36 h or longer reduced the final length and the rate of extension of both the plumule and radicle. Combining information about germination in salt solution with that about seed quality enabled a distinction to be made between varieties which performed poorly because they were genetically salt-susceptible from those which germinated poorly due to poor seed quality. It is argued that the seed vigour of seed lots used in genotype evaluation should be assessed in order to avoid discarding potentially useful genotypes because of poor physiological seed quality.
This study was undertaken to investigate the independent effect of the length of birth interval on malnutrition in infants, and children aged 6–39 months. Data for this study were drawn from a post-flood survey conducted during October–December 1988 at Sirajganj of the Sirajgani district and at Gopalpur of the Tangail district in Bangladesh. The survey recorded the individual weights of 1887 children. Cross-tabulations and logistic regression procedures were applied to analyse the data. The proportion of children whose weight-for-age was below 70% (moderate-to-severely malnourished) and 60% (severely malnourished) of the NCHS median was tabulated against various durations of previous and subsequent birth intervals. The odds of being moderately or severely malnourished were computed for various birth intervals, controlling for: the number of older surviving siblings; maternal education and age; housing area (a proxy for wealth); age and sex of the index child; and the prevalence of diarrhoea in the previous 2 weeks for the index child.
About one-third of infants and young children were moderately malnourished and 15% were severely malnourished. The proportion of children who were under 60% weight-for-age decreased with the increase in the length of the subsequent birth interval, maternal education and housing area. The proportion of malnourished children increased with the number of older surviving children. Children were at higher risk of malnutrition if they were female, their mothers were less educated, they had several siblings, and either previous or subsequent siblings were born within 24 months. This study indicates the potential importance of longer birth intervals in reducing malnutrition in children.
The precise pore sizes defined by crystalline zeolite lattices have led to intensive research on zeolite membranes. Unfortunately zeolites have proven to be extremely difficult to prepare in a defect-free thin film form needed for membrane flux and selectivity. We introduce tetrapropylammonium TPA (a structure directing agent for zeolite ZSM-5) into a silica sol and exploit the development of high solvation stresses to create templated amorphous silicas with pore apertures comparable in size to those of ZSM-5. 29Si and 2H NMR experiments were performed to evaluate the efficacy of our templating approach. The 29Si NMR spectrum of the silica matrix was observed by an intermolecular cross-polarization experiment between the 1H nuclei of TPA and the 29Si nuclei in the silica matrix. The efficiency of the cross-polarization interaction was used to investigate the degree to which the matrix formed a tight cage surrounding the template molecule. Bulk xerogels, prepared by gelation and slow drying of the corresponding sols, exhibited only weak interactions between the two sets of nuclei. Thin film xeorgels, where drying stresses are greater, resulted in significantly increased interactions. Analogous materials were prepared using fully deuterated TPA. The 2H NMR wideline spectra consisted of a partially narrowed resonance, corresponding to template molecules which were undergoing restricted rotational motion, and an isotropically narrowed resonance, corresponding to molecules which were undergoing rapid rotational motion. The number of isotropically rotating template molecules decreased for the thin film specimens, consistent with improved templating of amorphous silica by TPA.
An understanding of dielectric breakdown mechanisms is critical for continued oxide scaling. Although working transistors have been demonstrated with sub-2nm SiO2 gate dielectrics, the manufacturability of such devices hinges on the reliability of the oxide. As oxides become thinner and operating voltages become lower, a fundamentally different mode of dielectric breakdown occurs. This has been called soft breakdown and is considered to be the formation of a small, localized tunneling path through a dielectric. For transistors with 2-nm gate oxides, threshold voltage and maximum transconductance are not affected by soft breakdown, implying that circuits may continue to operate after soft breakdown. The increase in gate current or voltage noise associated with soft breakdown is not a limiting factor for many applications. However, some cases will be shown in which soft breakdown does degrade device function.
In order to make comparisons of ultra-thin oxide quality, it is important to be able to reliably detect soft breakdown. J-ramp, a commonly used ramped-current measurement to determine oxide quality, is unable to detect soft breakdown in ultra-thin oxides. We will demonstrate the incorporation of noise measurements in a commercial J-ramp algorithm.