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Prolonged conditions of chronic stress have the potential to cause mental health difficulties and disrupt developmental processes for children and adolescents. Natural disasters disproportionately affect low-resource areas, yet little is known about the interaction between trauma exposure, chronic stressors, and mental health.
To determine the rates of post-traumatic stress disorder (PTSD), depression and anxiety among adolescents affected by earthquakes in China and Nepal, and examine the specific roles of trauma exposure and chronic stressors across the three mental health outcomes.
A school-based, cross-sectional study of 4,215 adolescents (53% female, ages 15-19 years) was conducted in disaster-affected areas of southern China and Nepal. Participants completed a series of translated and culturally adapted standardized assessments. Mixed effects logistic regression analyses were conducted for each mental health outcome.
The overall rate of PTSD was 22.7% and was higher among Nepalese participants (China: 19.4% vs. Nepal: 26.8%, p<0.001), but did not differ between genders (China: p=0.087 and Nepal: p=0.758). In both countries, the level of trauma exposure was a significant risk factor for PTSD, depression, and anxiety (China: OR’s 1.09-1.18 and Nepal: OR’s 1.08-1.13). Chronic stressors significantly improved the model and further contributed to mental health outcomes (China: OR’s 1.23-1.26 and Nepal: OR’s 1.10-1.23). Multilevel risk and protective factors across all mental health outcomes will be presented.
While there are limited opportunities to protect adolescents from disaster exposure, there is significant potential to address the effects of ongoing economic insecurity, domestic violence, and school cessation that are likely to worsen mental health outcomes. Programs that identify chronic stressors for adolescents in disaster-affected settings, and work to address poverty and violence, will have cascading effects for mental health, development, and security.
More than half of the world’s youth live in the Asia Pacific region, yet efforts to reduce disaster risk for adolescents are hindered by an absence of age-specific data on protection, health, and engagement.
China and Nepal have faced a recent escalation in the number of climatic and geological hazards affecting urban and rural communities. We aimed to examine disaster-related threats experienced by adolescents and their caregivers in China and Nepal, determine the scope for adolescent participation, and elicit recommendations for improving disaster risk reduction.
Sixty-nine adolescents (51% female, ages 13-19) and 72 adults (47% female, ages 22-66) participated in key informant interviews and focus group discussions in disaster-affected areas of southern China and Nepal. Using inductive content analysis, several themes were identified as key to adolescents’ needs.
Security and protection emerged as a central issue, interlinked with preparedness, timely and equitable disaster response, psychosocial support, and adolescent participation. The mental health risks emerging from trauma exposure were substantial. Adolescents made extensive contributions to disaster response including involvement in rescue efforts and delivering first aid, rebuilding homes and caring for family members. Participants forwarded a number of recommendations, including investing in psychological support, skills training, and stronger systems of protection for those at risk of family separation, trafficking, or removal from school.
The findings informed a multilevel, interconnected model for disaster risk reduction tailored to adolescents’ needs. Supporting adolescents’ recovery and long-term resilience after humanitarian crises will require coordinated efforts in preparedness, security, and mental health care.
The shape- and structure-directing ability of capping agents, namely, acetic acid (AA) and folic acid (FA), has been analyzed in the synthesis of hollow plasmonic nanostructures via the nanoscale Kirkendall effect. FA was found to possess both shape-directing and structure-directing abilities when spherical solid Ag2O nanoparticles were transformed into hollow silver nanocubes (HAgNCs). In contrast, AA acted only as a structure-directing agent in the transformation from solid Ag2O nanospheres to hollow Ag nanospheres (HAgNSs). FA capping leads to enhanced plasmon tunability range from 535 to 640 nm in the hollow silver nanostructures. The size and shape of nanostructures were analyzed by high-resolution transmission electron microscopy (HRTEM). HRTEM revealed that the outer diameter of AA-capped HAgNSs is 50 ± 10 nm while edge-length for FA-capped HAgNCs is 100 ± 15 nm. The diameter of inner void space was found to be 30 ± 5 and 43 ± 5 nm for HAgNSs and HAgNCs, respectively. The phase purity of the hollow nanostructures was confirmed by X-ray diffraction and energy dispersive X-ray measurements. Due to unique structural and plasmonic features, FA-capped HAgNCs are well-suited for biomedical applications.
The present work aims to understand the effect of zinc and rare-earth element addition (i.e., 2 wt% Gd, 2 wt% Dy, and 2 wt% of Gd and Nd individually) on the microstructure evolution, mechanical properties, in vitro corrosion behavior, and cytotoxicity of Mg for biomedical application. The microstructure results indicate that the Mg–Zn–Gd alloy consists of the lamellar long period stacking ordered phase. The electrochemical and immersion corrosion behavior were studied in Hanks balanced salt solution. Enhanced corrosion resistance with reduced hydrogen evolution volume and magnesium (Mg2+) ion release were estimated for the Mg–Zn–Gd alloy as compared to the other two alloy systems. At the early stage of corrosion, formation of the oxide film inhibited the corrosion propagation. However, at the later stages, the breaking of the oxide film leads to shallow pitting mode of corrosion. The ultimate tensile strength of Mg–Zn–Gd–Nd is better than the other two alloys due to the uniform distribution of the Mg12Nd precipitate phase. The moderate strength in the Mg–Zn–Gd alloy is due to the low volume fraction of the secondary phase. The MTT (methylthiazoldiphenyl-tetrazolium bromide) assay study was carried out to understand the cell cytotoxicity on the alloy surfaces. Studies revealed that all three alloys had significant cellular adherence and no adverse effect on cells.
The Murshidabad District of West Bengal, India has practised traditional mulberry sericulture since time immemorial. One of the most important aspects for sustainable development of the sericulture industry is the control and prevention of silkworm diseases. The main objective of this study was to determine silkworm disease incidence over the period 1992–2011 in Murshidabad District and how environmental factors have contributed towards their occurrence. Data were collected from a crop-wise survey of silkworm diseases from 25 farmers (five farmers from five villages), who each had a separate rearing house, were progressive and had a capacity of rearing at least 100 disease free layings (dfls) in each crop. Disease incidence was expressed in percentage and calculated taking into consideration 40,000 larvae per 100 dfls. Crop-wise silkworm disease mortality data were correlated with meteorological data. Data collected from the continuous survey conducted in the district during 1992–2011 revealed that there was no set pattern of occurrence of silkworm diseases. However, maximum mortality (up to 30%) of silkworm due to diseases in all the seasons occurred mainly due to grasserie, as relative humidity remains high for most part of the year in this area. However, other than grasserie, for most of the period, disease incidence was below 10%. This observation of the dominance of grasserie over other diseases in causing silkworm mortality calls for renewed emphasis on the preventive measures and development of disease forecasting models, for disease control. Another observation was that since 1993, pebrine, the deadliest disease of the silkworm, has not been reported from the farmers’ fields.
Accumulative roll bonding (ARB) process was used to develop Mg–6% Zn/Al and Mg–6% Zn/anodized–Al multilayered composites. Microstructural characterization was done using scanning electron microscopy, energy-dispersive X-ray spectroscopy, electron backscattered diffraction, and transmission electron microscopy. An average grain size measured in the roll-bonded layers of Al, anodized Al, and Mg–2% Zn was found to be 1.8 μm, 1.6 μm, and 0.6 μm, respectively. Phases Al17Mg12, AlMg4Zn11, and Al2O3 after 5-pass of ARB were confirmed by X-ray diffraction analysis. The Mg–6% Zn/Al and Mg–6% Zn/anodized Al composites exhibited tensile strengths ∼252 MPa and ∼256 MPa, respectively, after a 5-pass ARB process. Hardness of the individual layers of composite increased linearly with an increase in the number of ARB passes. Fractographs of the multilayered composite illustrated the ductile failure in Al and anodized Al layers and transgranular brittle fracture in Mg–6% Zn layers.
An outbreak of influenza A(H1N1)pdm09 was detected during the ongoing community-based surveillance of influenza-like illness (ILI). Among reported 119 influenza A(H1N1)pdm09 cases (59 cases in the year 2012 and 60 cases in 2015) in summer months, common clinical features were fever (100%), cough (90·7%), sore throat (85·7%), nasal discharge (48·7%), headache (55·5%), fatigue (18·5%), breathlessness (3·4%), and ear discharge (1·7%). Rise in ILI cases were negatively correlated with the seasonal factors such as relative humidity (Karl Pearson's correlation coefficient, i.e. r = −0·71 in the year 2012 and r = −0·44 in the year 2015), while rise in ILI cases were positively correlated with the temperature difference (r = 0·44 in the year 2012 and r = 0·77 in the year 2015). The effective reproduction number R, was estimated to be 1·30 in 2012 and 1·64 in 2015. The study highlights the rise in unusual influenza activity in summer month with high attack rate of ILI among children aged ⩽9 years. Children in this age group may need special attention for influenza vaccination. Influenza A(H1N1)pdm09 outbreak was confirmed in inter-seasonal months during the surveillance of ILI in Pune, India, 2012–2015.
In April 2015 a 7.8-magnitude earthquake hit Nepal. As part of relief operations named Operation Maitri, the Indian Armed Forces deployed 3 field hospitals in the disaster zone. Rapid deployment of mobile surgical teams to far-flung, inaccessible areas was done by helicopters. In an operational deployment spanning 1 month, a total of 7532 patients were treated and 105 surgeries were carried out on 83 patients. One-fifth of the patients were less than 18 years of age. One-third of the patients had traumatic injuries directly attributable to the earthquake, whereas the remaining patients were treated for diseases of poor sanitation and hygiene as well as chronic illness that had been neglected owing to the collapse of the local health infrastructure. Cases of traumatic injuries directly related to the earthquake were seen maximally on the 5th day after the index event but tapered off rapidly by the 10th day. Nontraumatic illness required more attention thereafter and a need was felt for separate child health and reproductive health services later in the mission. Although immediate management of injuries and surgical intervention in selected cases was possible, ensuring long-term care and rehabilitation of cases proved problematic. This was especially so for spinal injury cases. Data capturing by a paper-based system was found to be inadequate. The lessons learned from this mission have led to a reimagining of the composition of future relief operations. Apart from mobile surgical teams, on which conventional field hospitals are generally centered, a separate section for preventive medicine and child and maternal services is needed. (Disaster Med Public Health Preparedness. 2017;11:394–398)
During the course of chemical evolution the role of metal oxides may have been very significant in catalysing the polymerization of biomonomers. The peptide bond formation of alanine (ala) and glycine (gly) in the presence of various oxides of manganese were performed for a period of 35 days at three different temperatures 50, 90 and 120°C without applying drying/wetting cycling. The reaction was monitored every week. The products formed were characterized by high-performance liquid chromatography and electrospray ionization–mass spectrometry techniques. Trace amount of oligomers was observed at 50°C. Maximum yield of peptides was found after 35 days at 90°C. It is important to note that very high temperatures of 120°C favoured the formation of diketopiperazine derivatives. Different types of manganese oxides [manganosite (MnO), bixbyite (Mn2O3), hausmannite (Mn3O4) and pyrolusite (MnO2)] were used as catalyst. The MnO catalysed glycine to cyclic (Gly)2, (Gly)2 and (Gly)3, and alanine, to cyclic (Ala)2 and (Ala)2. Mn3O4 also produced the same products but in lesser yield, while Mn2O3 and MnO2 produced cyclic anhydride of glycine and alanine with a trace amount of dimers and trimmers. Manganese of lower oxidation state is much more efficient in propagating the reaction than higher oxidation states. The possible mechanism of these reactions and the relevance of the results for the prebiotic chemistry are discussed.
The role of manganese oxides in concentrating organic moieties and offering catalytic activity for prebiotic reactions is investigated by studying their interaction with different aromatic amines such as aniline, p-chloroaniline, p-toluidine and p-anisidine. For all amines, metal oxides showed highest adsorption at neutral pH. The order of their adsorption capacity and affinity as revealed by the Langmuir constants was found to be manganosite (MnO) > bixbyite (Mn2O3) > hausmannite (Mn3O4) > and pyrolusite (MnO2). At alkaline pH, these manganese oxides offered their surfaces for oxidation of amines to form coloured oligomers. Analysis of the oxidation products by gas chromatography–mass spectrometry showed the formation of a dimer from p-anisidine and p-chloroaniline, while a trimer and tetramer is formed from p-toluidine and aniline, respectively. A reaction mechanism is proposed for the formation of the oligomers. While field-emission scanning electron microscopic studies confirm the binding phenomenon, the Fourier transform infrared spectroscopy analysis suggests that the mechanism of binding of amines on the manganese oxides was primarily electrostatic. The adsorption behaviour of the studied aromatic amines followed the order: p-anisidine > p-toluidine > aniline > p-chloroaniline, which is related to the basicities and structure of the amines. Our studies confirmed the significance of the role of manganese oxides in prebiotic chemistry.
We report on identification of core collection from 192 accessions collected from 12 Indian states and five other countries based on 109 polymorphic amplified fragment length polymorphism (AFLP) markers. Pairwise Jaccard's similarity coefficient for accessions varied from 0.25 to 1 with a maximum genetic distance of 0.75 obtained between accessions Jc428 (from Mexico) and J204 (from Madurai, Tamil Nadu). Both UPGMA (Unweighted Pair Group Method of Arithmetic Averages) clustering and principal coordinate analyses showed similar grouping of accessions in three major clusters in which Mexican accessions clustered separately from Indian, Chinese and African accessions. Results obtained from analysis of molecular variance indicated that 59% of the genetic variation was distributed among the populations, while 41% of variation was within the populations. A total of 16 (8.3% of the entire collection) core accessions were identified, which contained the entire allelic diversity of 192 accessions with respect to the sampled AFLP loci. The core accessions would be highly useful for future genetic improvement of Jatropha. To the best of our knowledge, this is the first report on identification of core accessions in Jatropha.
This paper describes the characteristics of damage, introduced under different conditions of diamond wire sawing, on the Si wafer surfaces. The damage occurs in the form of frozen-in dislocations, phase changes, and microcracks. The in-depth damage was determined by conventional ways such as TEM, SEM and angle-polishing/defect-etching, which only provide local information. We have also applied a new technique based on sequential measurement of the minority carrier lifetime after etching thin layers from the surfaces to determine average damage depth and its in-depth distribution. The lateral spatial damage variations, which seem to be mainly related to wire reciprocation process, were observed by photoluminescence and lifetime mapping. Our results show a strong correlation of damage depth on the diamond grit size and wire usage.
The scales of fast-swimming sharks contain riblet structures with microgrooves, aligned in the direction of fluid flow, that result in water moving efficiently over the surface. In previous studies, these riblet structures have shown a drag reduction of up to 10 % when compared with a smooth, flat surface. These studies have suggested two prevalent drag-reduction mechanisms which involve the effect of vortices and turbulence fluctuations. To further explore relevant mechanisms and study the effect of riblet geometry and flow properties on drag, vortices and turbulence fluctuations, various shark-skin-inspired riblet structures were created using computational models in which velocity, viscosity, spacing, height and thickness parameters were independently modified. A relevant mechanism of drag reduction is discussed to relate riblet parameters and flow properties to drag change and vortex size. Modelling information will lead to a better understanding of riblets and allow for optimum drag-reducing designs for applications in marine, medical and industrial fields.
In this paper, we will describe the nature of defects and impurities in thick epitaxial-Si layers and their influence on the cell efficiency. These wafers have very low average dislocation density. Stacking faults (SFs) are the main defect in epi layers. They can occur in many configurations—be isolated, intersecting, and nested. When nested, they can be accompanied by formation of coherent twins resulting in dendritic growth, with pyramids protruding out of the wafer surface. Such pyramids create large local stresses and punch out dislocations. The main mechanism of dislocation formation is through pyramids. Stacking faults degrade solar cell performance. Analyses of the solar cells have revealed that the nested SFs have a controlling effect on the solar cell performance. A well-controlled growth can minimize defect generation and produce wafers that can yield cell efficiencies close to 20%.
This article reports temporal changes in the measured oceanic geochemical properties of the Arabian Sea and the equatorial Indian Ocean by reoccupying six stations investigated during the GEOSECS expedition in 1977 and 1978. Observed differences are interpreted in terms of plausible changes in the environment and climate that have occurred in response to natural or anthropogenic processes. The depth profiles of major parameters such as dissolved oxygen, ΣCO2, major nutrients (silicates, nitrates, and phosphates), and radiocarbon in dissolved inorganic carbon were measured during the cruises between 1994 and 1998 along with temperature and salinity. Most stations in the Arabian Sea show an increase in salinity by ∼0.2 to 0.3 salinity units in the top 400 m, whereas one station in the equatorial Indian Ocean showed a decrease in salinity by ∼0.1 units, indicating a likely change in the evaporation-precipitation (E-P) balance. The ΣCO2 increased by an average of 8 μM within the top 1200 m of the Arabian Sea. The depth profiles of nitrates and dissolved oxygen for the central Arabian Sea stations show significant variations, while only marginal changes are seen for silicates and phosphates relative to the GEOSECS data. The decrease in Δ14C of surface waters is due to the steady decrease in atmospheric 14C concentration since GEOSECS, and the Δ14C increase in subsurface waters is attributed to the downward vertical diffusion of bomb 14C interpreted in terms of atmosphere to ocean transfer and lateral advection of water masses.
We describe appropriate wafer cleaning procedure and surface passivation characteristics of various passivants used for making measurement of minority carrier lifetime (τB ) of very high quality Si wafers. These passivants include: iodine ethanol (I-E), quinhydrone methanol (QH-M), SiO2, and Al2O3. The issues related to the passivation stability and the spatial uniformity for mapping τB are also discussed.
A waveguide shunt slot-fed microstrip patch antenna (WGMPA) element is proposed and analyzed with method of moments (MOM) using entire-domain basis functions. The developed analysis has been utilized to obtain parametric observation of power-coupling versus transverse offset of feeding slot from the waveguide axis. Expressions for the radiation pattern as a summation of contributions of individual basis functions are reported. The proposed element is amenable to building-up series-fed linear arrays by a simple cascading of elements at the through-end of the feeding waveguide. The authors propose that arbitrary amplitude excitations may be applied to such linear arrays for desired tailored array pattern characteristics. The required transverse offsets for each array element may be computed using the reported parametric result. As a demonstration of concept, two distributions are designed – uniform amplitudes and Dolph–Chebyshev for reduced side lobes. Computed element patterns from MOM are used with an array factor formulation for arbitrary element positions. Both modules show radiation characteristics closely matching the expected directivity and sidelobe envelopes. Analysis validation is achieved using a proven finite element method (FEM)-based solver; the comparison is close and is reported. Efficacy of the waveguide shunt-slot fed patch element for building linear array modules with prescribed amplitude distributions is thus established.
3D integration enabled by through-silicon-via (TSV) allows continued performance enhancement and power reduction for semiconductor devices, even without further scaling. For TSV wafers with all Applied Materials unit processes, we evaluate the integrity of oxide liner and copper barrier by capacitance-voltage (C-V) and current-voltage (I-V) measurements, from which oxide capacitance, minimum TSV capacitance, and leakage current are extracted. The capacitance values match well with model predictions. The leakage data also demonstrate good wafer-scale uniformity. The liner and barrier quality are further verified with microanalysis techniques.
Pebrine caused by Nosema bombycis in the silkworm Bombyx mori L. causes severe economic loss to the sericulture industry. Several species of microsporidia and strains of N. bombycis have been isolated from infected silkworms. The study of the developmental stages of any parasite is important, as it leads to the identification of stages that may be susceptible to control measures. For this study, five microsporidian isolates from B. mori were collected from five different locations in West Bengal, India and a study of the developmental stages from mid-gut smears and histological techniques was undertaken. The observations of mid-gut smears and histological specimens revealed differences in the morphometry and duration of different developmental stages of the parasites.
Among other reliability concerns, the dielectric charging is considered the major failure mechanism which hinders the commercialization of electrostatic capacitive radio frequency micro-electro-mechanical systems (RF MEMS) switches. In this study, Kelvin probe force microscopy (KPFM) surface potential measurements have been employed to study this phenomenon. Several novel KPFM-based characterization methods have been proposed to investigate the charging in bare dielectric films, metal–insulator–metal (MIM) capacitors, and MEMS switches, and the results from these methods have been correlated. The used dielectric material is plasma-enhanced chemical vapor deposition (PECVD) silicon nitride. The SiNx films have been charged by using a biased atomic force microscope (AFM) tip or by electrically stressing MIM capacitors and MEMS switches. The influence of several parameters on the dielectric charging has been studied: dielectric film thickness, deposition conditions, and under layers. Fourier transform infra-red (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) material characterization techniques have been used to determine the chemical bonds and compositions, respectively, of the SiNx films. The data from the physical material characterization have been correlated to the KPFM results. The study provides an accurate understanding of the charging/discharging processes in dielectric films implemented in electrostatic MEMS devices.