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Despite the magnitude and protracted nature of the Rohingya refugee situation, there is limited information on the culture, mental health and psychosocial wellbeing of this group. This paper, drawing on a report commissioned by the United Nations High Commissioner for Refugees (UNHCR), aims to provide a comprehensive synthesis of the literature on mental health and psychosocial wellbeing of Rohingya refugees, including an examination of associated cultural factors. The ultimate objective is to assist humanitarian actors and agencies in providing culturally relevant Mental Health and Psychosocial Support (MHPSS) for Rohingya refugees displaced to Bangladesh and other neighbouring countries.
We conducted a systematic search across multiple sources of information with reference to the contextual, social, economic, cultural, mental health and health-related factors amongst Rohingya refugees living in the Asia-Pacific and other regions. The search covered online databases of diverse disciplines (e.g. medicine, psychology, anthropology), grey literature, as well as unpublished reports from non-profit organisations and United Nations agencies published until 2018.
The legacy of prolonged exposure to conflict and persecution compounded by protracted conditions of deprivations and displacement is likely to increase the refugees' vulnerability to wide array of mental health problems including posttraumatic stress disorder, anxiety, depression and suicidal ideation. High rates of sexual and gender-based violence, lack of privacy and safe spaces and limited access to integrated psychosocial and mental health support remain issues of concern within the emergency operation in Bangladesh. Another challenge is the limited understanding amongst the MHPSS personnel in Bangladesh and elsewhere of the language, culture and help-seeking behaviour of Rohingya refugees. While the Rohingya language has a considerable vocabulary for emotional and behavioural problems, there is limited correspondence between these Rohingya terms and western concepts of mental disorders. This hampers the provision of culturally sensitive and contextually relevant MHPSS services to these refugees.
The knowledge about the culture, context, migration history, idioms of distress, help-seeking behaviour and traditional healing methods, obtained from diverse sources can be applied in the design and delivery of culturally appropriate interventions. Attention to past exposure to traumatic events and losses need to be paired with attention for ongoing stressors and issues related to worries about the future. It is important to design MHPSS interventions in ways that mobilise the individual and collective strengths of Rohingya refugees and build on their resilience.
Co-circulation of Chikungunya and Dengue viral infections (CHIKV and DENV) have been reported mainly due to transmission by common Aedes vector. The purpose of the study was to identify and characterise the circulating strains of CHIKV and DENV in DENV endemic region of New Delhi during 2016. CHIKV and DENV were identified in the blood samples (n = 130) collected from suspected patients by RT-PCR. CHIKV was identified in 26 of 65 samples (40%). Similarly, DENV was detected in 48 of 120 samples (40%). Co-infection with both the viruses was identified in five (9%) of the samples. Interestingly, concurrent infection with DENV, CHIKV and Plasmodium vivax was detected in two samples. CHIKV strains (n = 11) belonged to the ECSA genotype whereas DENV-3 sequences (n = eight) clustered in Genotype III by phylogenetic analysis. Selection pressure of E1 protein of CHIKV and CprM protein of DENV-3 revealed purifying selection with four and two positive sites, respectively. Four amino acids of the CHIKV were positively selected and had high entropy suggesting probable variations. Co-circulation of both viruses in DENV endemic regions warrants effective monitoring of these emerging pathogens via comprehensive surveillance for implementation of effective control measures.
Shortages of hired labour are leading to greater interest in mechanisation for crop establishment in smallholder agriculture. Due to small field sizes, mechanised planters mounted on four-wheel tractors are not a suitable technology. The Versatile Multi-crop Planter (VMP) was developed for zero tillage (ZT), strip planting (SP) or single pass shallow tillage (SPST) on flat land and for forming and planting on tops of beds, each in a single pass operation, when mounted on a two-wheel tractor (2WT). The aim of the present study was to evaluate the field performance of the VMP in comparison to conventional broadcast seeding and full rotary tillage (2 to 4 passes; called CT) for establishing chickpea (Cicer arietinum L.), jute (Corchorus olitorius L.), lentil (Lens culinaris Medikus), maize (Zea mays L.), mung bean (Vigna radiata L. R. Wilczek), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) in 15 locations of Bangladesh. Plant populations emerging from all single pass operations viz. SP, ZT, and bed planting (BP) were generally satisfactory and in 12 out of 15 experiments plant populations after SP were similar to or greater than after CT. In addition, SP gave comparable or greater plant populations than SPST and BP planting methods. Overall, the SP planting achieved comparable yields and lower costs of establishment than CT. We conclude that effective and reliable planters are now available for sowing a range of crop species on small fields with minimum soil disturbance. This opens up realistic options for the development of mechanised conservation agriculture suited to small field sizes.
The study was aimed to identify, characterize and describe the phenotypic variation of indigenous goose populations in Bangladesh. The research was conducted at Sylhet Sadar Upazilla in Sylhet district and encompassed about 141 geese (74 brown type and 67 white type). Least Square Mean ± SE of body length, wing span, shank length, beak length and head length of mature indigenous goose were 73.47 ± 0.95, 134.53 ± 1.38, 9.27 ± 0.09, 8.88 ± 0.10 and 6.42 ± 0.02 cm, respectively. Males were significantly (p < 0.01) higher than their female counterparts for all morphometric traits but no significant differences (p > 0.05) were found between two types. The body weight of indigenous goose at day old, 2-week, 1-month, 2-month and 10-month of age were 95.45 ± 0.88, 148.59 ± 1.55, 407.34 ± 7.27 gm, 1.19 ± 0.03 kg and 3.65 ± 0.06 kg, respectively. Males were significantly (p < 0.01) heavier than females in all age groups except day old gosling but no significant difference (p > 0.05) were observed for body weights between two types of goose. Egg weight, egg length, egg width, incubation period, clutch size, number of eggs in a breeding season and age at first egg were 131.85 ± 1.70 gm, 7.40 ± 0.02 cm, 5.22 ± 0.02 cm, 30.30 ± 0.07 days, 7.42 ± 0.08, 20.52 ± 0.38 and 313.22 ± 3.03 days, respectively. The number of eggs in a breeding season of brown type were significantly (p < 0.05) higher than that of white type goose. This study provides a bench mark for the morphometric traits and performance of goose in Bangladesh.
Conservation agriculture (CA) is inadequately developed for rice-based cropping systems widely practiced in Bangladesh. The current drawback is the implementation of CA for all crops including rice (Oryza sativa L., ecotype ‘transplanted aman’ [T. aman]) to increase rice–wheat (Triticum aestivum L.) rotation productivity. It is important to identify the best combination of tillage types and cropping systems to achieve a high yield of component crops and improve soil health. Three tillage practices, assigned to main experimental plots [namely, zero tillage (ZT), conventional tillage using a rotary tiller (CT) and deep tillage using a chisel plough (DT)] and three different cropping systems, assigned to sub-plots [namely, WFT: wheat–fallow–T. aman, WMT: wheat–mungbean (Vigna radiata L. Wilczek)–T. aman and WDT: wheat–dhaincha (Sesbania rostrata)–T. aman], were tested. After 4 years, ZT under WDT and WMT significantly increased soil organic matter (SOM) at 0–150 mm depth, and these replicates also held the highest levels of total organic carbon. Soil organic carbon (C) increased at a rate of 1.17 and 1.14 t/ha/y in ZT under WDT and WMT, respectively, while CT and DT under WFT were almost unchanged. After 4 years, SOM build-up by the three-crop system (WDT and WMT) under ZT helped conserve soil moisture and improve other soil properties, such as reduction in soil strength and bulk density and increase plant available water content, thus maintaining an optimum soil water infiltration rate. Zero tillage under WMT and WDT showed significant improvements in root mass density of rice and wheat at increased soil depth. The WDT and WMT plots under DT consistently gave the highest yield followed by WDT and WMT under CT, in contrast with ZT under WMT or WDT, which showed the highest improvement in crop yields over the years. In summary, minimum soil disturbance together with incorporation of a legume/green manure crop into the rice–wheat system as well as the retention of their residues increased soil C status, improved soil properties and maximized grain yields.
Cholera is an important public health problem in Bangladesh. Interventions to prevent cholera depend on their cost-effectiveness which in turn depends on cholera incidence. Hospital-based diarrhoeal disease surveillance has been ongoing in six Bangladeshi hospitals where a systematic proportion of patients admitted with diarrhoea were enrolled and tested for Vibrio cholerae. However, incidence calculation using only hospital data underestimates the real disease burden because many ill persons seek treatment elsewhere. We conducted a healthcare utilization survey in the catchment areas of surveillance hospitals to estimate the proportion of severe diarrhoeal cases that were admitted to surveillance hospitals and estimated the population-based incidence of severe diarrhoea due to V. cholerae by combining both hospital surveillance and catchment area survey data. The estimated incidence of severe diarrhoea due to cholera ranged from 0·3 to 4·9/1000 population in the catchment area of surveillance hospitals. In children aged <5 years, incidence ranged from 1·0 to 11·0/1000 children. Diarrhoeal deaths were most common in the Chhatak Hospital's catchment area (18·5/100 000 population). This study provides a credible estimate of the incidence of severe diarrhoea due to cholera in Bangladesh, which can be used to assess the cost-effectiveness of cholera prevention activities.
Fertilizer application can play an important role in soil organic carbon (SOC) retention and dynamics. The mechanisms underlying long-term accumulation and protection of SOC in intensive maize cropping systems, however, have not been well documented for cool high-latitude rainfed areas. Based on a 23-year fertilization experiment under a continuous maize cropping system at Gongzhuling, Jilin Province, China, the effects of fertilization regimes on SOC content and soil aggregate-associated carbon (C) composition were investigated. Results showed that, within the 0–1·0 m soil profile, SOC contents decreased significantly with soil depth in all treatments. In the topsoil layer (0–0·2 m), SOC concentrations in balanced inorganic fertilizers plus farmyard manure (MNPK), fallow system (FAL) and balanced inorganic fertilizers plus maize straw residue (SNPK) treatments were significantly greater than initial levels by 61·0, 34·1 and 20·1%, respectively. The MNPK and SNPK treatments increased SOC content by 50·7 and 12·4% compared to the unfertilized control in the topsoil layer, whereas no significant differences were found between balanced inorganic nitrogen, phosphorus and potassium fertilizers (NPK) and the unfertilized control treatment. There were no significant differences in aggregate-size distribution among the unfertilized control, NPK and MNPK treatments, whereas the SNPK treatment significantly enhanced the formation of micro-aggregates (53–250 μm) and decreased the formation of silt+clay aggregates (<53 μm) compared to the unfertilized control, NPK and MNPK treatments. Moreover, SOC concentrations in all aggregate fractions in the MNPK treatment were the highest among treatments. Furthermore, the MNPK treatment significantly increased SOC stock in micro- and silt+clay aggregates, which may slow down C decomposition in the soil. These results indicate that long-term manure amendment can benefit SOC sequestration and stability in the black soil of Northeast China.
During the epitaxial bottom up growth of nanowire (NW) arrays, occasional kinks in growth direction can lead to intersecting and consequently self-welded crystalline connections between NWs. In order to study these self-welded metallurgical NW junctions, a NW bridge device architecture which requires no post-growth processing was used to grow and stabilize Si NW junctions. Scanning Photocurrent Microscopy (SPCM) was used to study the optoelectronic properties of the NW junctions as well as the characteristics of the NW bridge devices. SPCM measurements show a bias dependent photocurrent (PC) response at the NW junction indicating local band bending at this location. A decay of the PC response away from the junction is also seen in the secondary NW channel ensuring an electrical connection. These junction properties may be important for ensemble NW optical devices.
We present a practical technique for fabricating silicon nanowire bridges on pre-patterned Si electrodes arrays. Silicon nanowires, catalyzed by gold nanoparticles, were grown on silicon electrodes from HF treated Au colloid as well as on electrodes treated with poly-L-lysine. Negligible growth was observed on untreated substrates due to poor adhesion of gold nanoparticles to the hydrogen terminated Si surface. In contrast, the treatments significantly increased occurrence of silicon nanowire bridges, which can be attributed to improved deposition of gold nanoparticles on the surface. Deposition time and concentrations of colloids also affected the occurrence of SiNW bridges. These results indicate that our techniqute for fabricating nanowire bridge arrays will be useful for large-area nanowire applications.
In this paper we study the existence of periodic solutions of a Volterra type integral equation with infinite heredity. Banach fixed point theorem, Krasnosel'skii's fixed point theorem, and a combination of Krasnosel'skii's and Schaefer's fixed point theorems are employed in the analysis. The combination theorem of Krasnosel'skii and Schaefer requires an a priori bound on all solutions. We employ Liapunov's direct method to obtain such an a priori bound. In the process, we compare these theorems in terms of assumptions and outcomes.
Escherichia coli, a prominent waterborne pathogen, causes a variety of gastrointestinal and extraintestinal infections that depend on virulence determinants. To monitor natural aquatic systems for virulence-associated genes of E. coli, multiplex PCR was used in a survey covering 46 major natural water bodies in Bangladesh. DNA was extracted directly from water samples as well as from pre-enriched and enriched cultures during three successive seasons and assessed for E. coli virulotype distribution. From the five virulotypes, genes from the enterotoxigenic (ETEC), enteropathogenic (EPEC), and enterohaemorrhagic (EHEC) virulotypes were detected consistently, but genes from the enteroinvasive (EIEC) and enteroaggregative (EAEC) virulotypes were traced only occasionally. ETEC was the most prevalent virulotype, followed by EPEC. However, EIEC and EAEC virulotypes could not be detected in winter or the rainy season, respectively. Specific regional distribution patterns of different E. coli virulotypes and their temporal fluctuations were identified. These observations may assist with assessing seasonal risk and identifying vulnerable areas of the country prone to E. coli-associated outbreaks.
Level set methods have been used for Solid phase epitaxial regrowth, etching and deposition.This study is to model the growth of nickel silicide accurately using the level set method. NiSi growth has been observed to follow a linear-parabolic law which takes into account both diffusion and interfacial reaction. This linear-parabolic system is very similar to the Deal and Grove model of SiO2 growth. This model uses similar diffusion transport and reaction rate equations. This simulation models the growth of silicide coupling diffusion solutions to level-set techniques. Dual level sets have been used for top and bottom interface propagation of silicide; velocities were estimated based on nickel concentrations at both interfaces as well as diffusivity and reaction rate of nickel. This is important to predict precise shape of silicide that will allow current crowding and field focusing effects to be modeled in transport out of the intrinsic device into the contacting layers. These simulation models can be used for latest technology nodes at 45, 32, 22nm and special devices such as FinFET’s etc. The level set method is successfully implemented and verified in Florida Object Oriented Process Simulator and growth shapes matches well with the literature Transmission Electron Microscopy data.
We describe an experiment to interface and characterize silver nanoparticle (AgNPs) aggregates that are self-assembled and plastically deformable on a thin gold (Au) film deposited on glass substrate. The electrical characterization is done using an electrical nanoprobe attached to a nano-manipulator inside a scanning electron microscope (SEM). Electrical current-voltage (I-V) measurements are made between the electrical nanoprobe in contact with the nanoparticle and the Au film. The Ag nanoparticles have diameters ranging between ~200-800nm and are self-assembled on a thiolated 100nm Au film. Application of a contact force via the nanoprobe even after substantial particle deformation reveals initially a small non-linear current. Upon current annealing through Joule heating, significant improvement in the electrical contact at the AgNP/substrate interface was observed. This is most likely based on bonding of the AgNPs to the Au film after passage of a high current. The need for such an annealing/sintering step will be critical in forming good ohmic contacts at ambient conditions during transfer printing of semiconductor micro/nanopillars.
We report an experimental investigation on employing Ag nanoparticles to provide electrical and mechanical contacts between transfer-printed semiconductor devices in the shape of micro/nano- wires and pillars. The Ag nanoparticles have diameters ranging between 200-800nm and are assembled on a 200nm Au film deposited on glass substrates. With a customized tool, an ensemble of silicon pillars were brought into contact with the silver (Ag) nanoparticles (AgNPs) by precisely controlling the displacement and applied force (pressure). Current-voltage measurements were done at force resolution of ~0.2N. The test method aims to illuminate the pillar-particle contact mechanism using the nanoparticles as conductive fillers for the next generation of high performance heteroepitaxial device transfer-printing applications.
In this work we have studied the importance of thermal effects on the structural and transport properties of Ag atomic-size nanowires (NWs) generated by mechanical stretching. Our study involve time-resolved atomic high resolution transmission electron microscopy imaging and quantum conductance measurement using an ultra-high-vacuum mechanically controllable break junction combined with quantum transport calculations. We have observed drastic changes in conductance and structural properties of Ag NWs generated at different temperatures (150 and 300 K). By combining electron microscopy images, electronic transport measurements and theoretical modeling, we have been able to establish a consistent correlation between the conductance and structural properties of Ag NWs. In particular, our study has revealed the formation of metastable rectangular rod-like Ag wires along the  crystallographic direction.
Uptake of oestrogens into breast tissue and their subsequent metabolism can be studied by infusing radio-labelled steroids into volunteer patients. Such studies show that oestradiol is preferentially accumulated in breast tumours, oestradiol concentrations exceeding those of oestrone. This contrasts with plasma, in which oestrone concentrations in postmenopausal women are greater than those of the oestradiol. This observation suggests that tissue factors can modulate local oestrogen metabolism, and thus local steroid concentrations.
We have studied the local production of oestrogens from androgen, and also the interconversion of the major oestrogens, oestrone and oestradiol. Using isotopic techniques, it is possible to calculate the proportion of endogenous oestrogen produced from androgen, as opposed to uptake from the circulation. These studies suggest that a very variable proportion of tissue oestrogen derives from endogenous synthesis. After administration of aromatase inhibitors, aromatase activity is substantially inhibited, both in vivo and in vitro.
Relative oestrogen concentrations are determined in part by the activity of oestradiol dehydrogenase. In breast tissue, dehydrogenase activity is present and this is modified by various factors, including androgens. In addition, we have demonstrated that normal, benign and malignant breast tissues produce factors which can modulate both growth and dehydrogenase activity of cancer cells in vitro.
We conclude that breast tissue is a site of synthesis of oestrogens, and that a number of factors can affect their local concentration. Tumour cells produce growth factors which can influence steroid metabolism, and may thus be able to enhance favourably their own endocrine environment.
New variants of Vibrio cholerae O1 have appeared in different time-frames in various endemic regions, especially in Asia and Africa. Sixty-nine strains of V. cholerae O1 isolated in Zambia between 1996 and 2004 were investigated by various genotypic techniques to determine the lineage of virulence signatures and clonality. All strains were positive for Vibrio seventh pandemic Islands (VSP)-I and VSP-II and repeat toxin (RTX) gene clusters attesting their El Tor lineage. Interestingly, strains isolated in recent times (2003–2004) were identified as an altered variant (El Tor biotype that harbours El Tor type rstR but produce classical ctxB) that replaced completely the progenitor El Tor strains prevalent in 1996–1997. Recent altered variant strains differed from prototype El Tor strains isolated earlier in that these strains lacked two ORFs, VC0493 and VC0498, in the VSP-II region. PFGE analysis revealed two major clonal lineages in the strains; cluster A represented the strains isolated before 2003 and cluster B the altered strains isolated in 2003–2004. Cluster A was closely related to prototype El Tor reference strain isolated in Bangladesh in 1971. Cluster B was found to be matched with Bangladeshi altered strains but was different from the hybrid strains isolated from Mozambique and Bangladesh. This report provides important information on the genesis of altered strains of V. cholerae O1 isolated in Zambia and emphasizes the need for further studies to follow the trends of evolutionary changes.
Disordered glass microsphere-epoxy composites have been used in a study of diffusional, electrical and mechanical effects of interfaces in polymer-matrix composites exposed to pure water. Mass gain measurements on composites manufactured from 10 μm silane-treated microspheres indicate initial near-Fickian diffusion with water saturation times on the order of 500 h. However, electrical measurements indicate water transport at rates at least 100 times more rapid. This behaviour is interpreted in terms of a cellular microstructure with areas of low cross-link density separating highly cross-linked areas. Rapid water transport can thus occur in areas of low cross-linking, even without the contribution of connected clusters of particles where rapid interfacial water transport occurs substantially ahead of the main diffusion front. Reductions in ultimate tensile strength and fracture energy in dry and water-saturated tensile test specimens are observed with increasing volume fraction of glass spheres but with a distinct plateau between about 6% and 12% Vf. This can be explained in terms of secondary cracking below the percolation threshold which causes toughening of the composite. However, a few % above pc (≍ 16%), most particles belong to the percolating cluster and the primary crack can grow without hindrance.
Al/PS junctions are non-rectifying and quasi-linear whereas Al/PS/c-Si junctions are weakly rectifying. The rectifying behavior is due to PS/c-Si heterojunction. The diode ideality factor (n) is about 8 for bias ≤0.5 V (about 50 for bias ≤5 V) at forward bias and nearly 1 for ≤0.5 V at reverse bias. As the temperature decreases, n at both forward and reverse biases increases. Different current transport mechanisms are found to be operating across the PS/c-Si junctions under forward and reverse biases. The barrier height measured from I-V data for ≤0.5 V is higher for forward bias than that for reverse bias. For high reverse biases (>5 V), the reverse current increases slowly following In(I)∝ V1/2 law. I-V results on PS/c-Si junctions are explained by a multi tunneling-recombination model for forward bias while carrier generation-recombination and barrier lowering effects for reverse bias.
The photoluminescence (PL) intensity first increases with anodization time (ta) and then decreases at very large ta. The increase in PL intensity with ta may be understood if the PL intensity is taken to be proportional to the effective volume of porous silicon (PS) layer under the probe laser beam. The effective volume of PS layer will be proportional to its thickness and reciprocal to the porosity. For a fixed anodization condition, the thickness and porosity both increase with ta. The increase in thickness increases the effective PS volume, while the increase in porosity causes the effective volume to decrease. Therefore, the intensity variation is governed by these two parameters: thickness and porosity. The observed results suggest that the thickness dominates the PL intensity initially and then the porosity becomes more important for very long ta. The PS layers prepared under ambient light illumination also exhibited the similar behaviour. The intensity variation with ta was explained as the interplay of thickness and porosity variations with ta.