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BACKGROUND: Conflicts adversely affect psychological well-being and are associated with mental disorders. AIM: The study aims to assess the levels of perceived stress, anxiety and depression and their association with demographic factors among the youth in the border villages of Jammu and Kashmir (J&K). METHODS: A cross-sectional study was conducted among youth aged 18 to 25 years. The sample consisted of 300 individuals from the border villages of J&K. Of these, 150 individuals were from the villages located near the International Border (IB) in the Jammu district, and 150 individuals were from the villages near the Line Of Control (LOC) in the Rajouri district. Perceived Stress scale (PSS), Generalised Anxiety Disorder (GAD7), and Public Health Questionnaire (PHQ9) scales were used to determine the levels of perceived stress, depression, and anxiety. Mann Whitney, Chi-square and Odds ratio analysis were performed to assess the levels of the indicators and their association with demographic factors. RESULTS: 94% of the respondents had perceived stress, 34.46% anxiety and 31% depression. Perceived stress, anxiety and depression were significantly higher among the LOC youth than IB youth (p < .00*). The LOC youth with an educational status below graduation level were found to be more anxious (p = .034) and more depressed (p = .003) than those with the educational status of graduation and above. The youth whose main activity was that of a student were found to be more depressed than the employed and unemployed youth (p = .000). CONCLUSION: Perceived stress, anxiety, and depression were prevalent among the youth in border villages. These were found to be significantly higher among youth in border villages on the LOC. The findings suggest that education level has a significant impact on the mental health of the youth.
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Depresión , Estrés Psicológico , Adolescente , Humanos , Depresión/epidemiología , Depresión/psicología , Estudios Transversales , Estrés Psicológico/epidemiología , Estrés Psicológico/psicología , Ansiedad/epidemiología , Ansiedad/psicología , Trastornos de AnsiedadRESUMEN
Nanowire/nanotube memristor devices provide great potential for random-access high-density resistance storage. However, fabricating high-quality and stable memristors is still challenging. This paper reports multileveled resistance states of tellurium (Te) nanotube based on the clean-room free femtosecond laser nano-joining method. The temperature for the entire fabrication process was maintained below 190 °C. A femtosecond laser joining technique was used to form nanowire memristor units with enhanced properties. Femtosecond (fs) laser-irradiated silver-tellurium nanotube-silver structures resulted in plasmonic-enhanced optical joining with minimal local thermal effects. This produced a junction between the Te nanotube and the silver film substrate with enhanced electrical contacts. Noticeable changes in memristor behavior were observed after fs laser irradiation. Capacitor-coupled multilevel memristor behavior was observed. Compared to previous metal oxide nanowire-based memristors, the reported Te nanotube memristor system displayed a nearly two-order stronger current response. The research displays that the multileveled resistance state is rewritable with a negative bias.
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Copper nanowires (CuNWs) are a key building block to facilitate carrier conduction across a broad range of nanodevices. For integration into nanoscale devices, manipulation and welding of these nanowires need to be overcome. Based on high energy density laser processing investigation, we report on innovative welding of single CuNWs to a silver film using a tightly focused laser beam combined with manipulation of CuNWs through the dielectrophoresis (DEP) method. Two types of lasers, femtosecond (FS) and continuous-wave (CW), were employed to analyze, improve, and control Cu-NW melting characteristics under high energy density irradiation. The FS laser welding of CuNWs resulted in a metallic joint with a low contact resistance suitable for functional electronic nanodevices. Computational simulations using the 1-D heat diffusion equation and finite difference method (FDM) were performed to gain an insight into metal-laser interactions for high performance welded contact development. Simulation studies on lasers established contrasting melting behavior of metal under laser irradiation. The device feasibility of CuNW based welded contacts was evaluated in terms of the electrical performance of a glucose sensor. It was possible to sense glucose concentration down to 10-6 M, demonstrating a path towards integration of CuNWs into wearable, flexible nanoelectronic devices.
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BACKGROUND: Indigenous populations in India are amongst the poorest and most marginalized population groups experiencing severe health deprivation. AIM: The present study is the first study that aims to understand the association of micronutrient deficiencies (vitamin B12 and folate) and MTHFR C677T gene polymorphism with depression and generalized anxiety disorder (GAD) among the Bhil indigenous population of India. METHODS: A total of 303 participants aged 25-65 years of both sexes and unrelated up to first cousins belonging to Bhil indigenous population were recruited for the present study. Depression and generalized anxiety disorder were assessed using Patient Health Questionnaire and Generalized Anxiety Disorder scale, respectively. Biochemical analysis, DNA extraction and MTHFR C677T gene polymorphism analysis were done using standard protocols. RESULTS: Although, vitamin B12 and folate status was not found to be directly associated with depression and GAD, but hyperhomocysteinemia was posing more than three folds and six folds significant increased risk for depression and GAD, respectively. Further, it seems hyperhomocysteinemia was mediated by vitamin B12 deficiency among depressed and anxious individuals. T allele of MTHFR C677T gene polymorphism was posing increased risk for depression and anxiety disorder though not significant. CONCLUSION: The present study highlights the significance of micronutrient deficiencies in the causation of depression and anxiety disorder.
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Trastornos de Ansiedad/etiología , Depresión/etiología , Hiperhomocisteinemia/etiología , Grupos de Población , Deficiencia de Vitamina B 12/complicaciones , Adulto , Trastornos de Ansiedad/sangre , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/fisiopatología , Estudios Transversales , Depresión/sangre , Depresión/epidemiología , Depresión/fisiopatología , Femenino , Ácido Fólico/sangre , Humanos , Hiperhomocisteinemia/sangre , Hiperhomocisteinemia/epidemiología , Hiperhomocisteinemia/fisiopatología , India/epidemiología , Masculino , Persona de Mediana Edad , Fenómenos Fisiológicos de la Nutrición , Necesidades Nutricionales , Polimorfismo Genético , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/epidemiología , Deficiencia de Vitamina B 12/fisiopatologíaRESUMEN
The purification of conductive polymer (e.g., polyaniline) particles is a challenging task, especially when the particle size is small. Herein, we demonstrate a unique strategy (electrode-based) to purify polyaniline particles by exploiting the difference in surface charge between particles and surfactants, and compare the results with a commonly used purification strategy (washing).
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We report a flexible sensor array electronic tongue system that is fabricated on a polymer substrate by the laser direct writing process for multiflavor detection. Electronic tongue is a sensing system that is applied to detect different elements with the same sensor array. By analyzing responses from different measurement units, it enables a cross-sensitivity, namely, the ability of the system to responding to a range of different analytes in solution without specific functionalization of sensors. In this article, a six-unit sensing array system was fabricated by a laser direct writing process. Sensing units were introduced on a flexible polyamide surface. A high surface-volume ratio porous carbon structure was created by a laser-induced carbonization process, which provides stable conductive carbon electrodes with high sensitivity. Different surface treatments, such as gold plating, reduced-graphene oxide coating, and polyaniline coating, were accomplished for different measurement units. By applying principal component analysis, this sensing system shows a promising result for the detection of multiple flavors. The detection limit for each element is about 0.1 mM for NaCl and sugar solutions. Also, it is able to detect 10-4 times diluted commercial table vinegar solution, which originally contains 5% acetic acid. The detection limit is theoretically lower than the human threshold of 10 mM for NaCl and sugar. Besides, the sensing system shows a high sensitivity and selectivity for mixed elements. By mapping the data points, the sensor system could detect flavor combinations and provide a reliable prediction of analyte concentration ratios.
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Aromatizantes/análisis , Análisis por Micromatrices/instrumentación , Análisis por Micromatrices/métodos , Oro/química , Grafito/químicaRESUMEN
Sequential NanoFermentation (SNF) is a novel process which entails sparging microbially produced gas containing H2S from a primary reactor through a concentrated metal-acetate solution contained in a secondary reactor, thereby precipitating metallic sulfide nanoparticles (e.g., ZnS, CuS, or SnS). SNF holds an advantage over single reactor nanoparticle synthesis strategies, because it avoids exposing the microorganisms to high concentrations of toxic metal and sulfide ions. Also, by segregating the nanoparticle products from biological materials, SNF avoids coating nanoparticles with bioproducts that alter their desired properties. Herein, we report the properties of ZnS nanoparticles formed from SNF as compared with ones produced directly in a primary reactor (i.e., conventional NanoFermentation, or "CNF"), commercially available ZnS, and ZnS chemically synthesized by bubbling H2S gas through a Zn-acetate solution. The ZnS nanoparticles produced by SNF provided improved optical properties due to their smaller crystallite size, smaller overall particle sizes, reduced biotic surface coatings, and reduced structural defects. SNF still maintained the advantages of NanoFermentation technology over chemical synthesis including scalability, reproducibility, and lower hazardous waste burden.
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Fermentación/fisiología , Nanopartículas del Metal/química , Sulfuros/química , Compuestos de Zinc/química , Gases/química , Tamaño de la Partícula , Reproducibilidad de los ResultadosRESUMEN
Simple and easily integrated design of flexible and transparent electrode materials affixed to polymer-based substrates hold great promise to have a revolutionary impact on the functionality and performance of energy storage devices for many future consumer electronics. Among these applications are touch sensors, roll-up displays, photovoltaic cells, health monitors, wireless sensors, and wearable communication devices. Here, we report an environmentally friendly, simple, and versatile approach to produce optically transparent and mechanically flexible all-solid-state supercapacitor devices. These supercapacitors were constructed on tin-doped indium oxide coated polyethylene terephthalate substrates by intercalation of a polymer-based gel electrolyte between two reduced graphene oxide (rGO) thin-film electrodes. The rGO electrodes were fabricated simply by drop-casting of graphene oxide (GO) films, followed by a novel low-temperature (≤250 °C) vacuum-assisted annealing approach for the in situ reduction of GO to rGO. A trade-off between the optical transparency and electrochemical performance is determined by the concentration of the GO in the initial dispersion, whereby the highest capacitance (â¼650 µF cm-2) occurs at a relatively lower optical transmittance (24%). Notably, the all-solid-state supercapacitors demonstrated excellent mechanical flexibility with a capacity retention rate above 90% under various bending angles and cycles. These attributes underscore the potential of the present approach to provide a path toward the realization of thin-film-based supercapacitors as flexible and transparent energy storage devices for a variety of practical applications.
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Stretchable electronic sensing devices are defining the path toward wearable electronics. High-performance flexible strain sensors attached on clothing or human skin are required for potential applications in the entertainment, health monitoring, and medical care sectors. In this work, conducting copper electrodes were fabricated on polydimethylsiloxane as sensitive stretchable microsensors by integrating laser direct writing and transfer printing approaches. The copper electrode was reduced from copper salt using laser writing rather than the general approach of printing with pre-synthesized copper or copper oxide nanoparticles. An electrical resistivity of 96 µΩ cm was achieved on 40-µm-thick Cu electrodes on flexible substrates. The motion sensing functionality successfully demonstrated a high sensitivity and mechanical robustness. This in situ fabrication method leads to a path toward electronic devices on flexible substrates.
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The thermophilic anaerobic metal-reducing bacterium Thermoanaerobacter sp. X513 efficiently produces zinc sulfide (ZnS) nanoparticles (NPs) in laboratory-scale (≤ 24-L) reactors. To determine whether this process can be up-scaled and adapted for pilot-plant production while maintaining NP yield and quality, a series of pilot-plant scale experiments were performed using 100-L and 900-L reactors. Pasteurization and N2-sparging replaced autoclaving and boiling for deoxygenating media in the transition from small-scale to pilot plant reactors. Consecutive 100-L batches using new or recycled media produced ZnS NPs with highly reproducible ~2-nm average crystallite size (ACS) and yields of ~0.5 g L(-1), similar to the small-scale batches. The 900-L pilot plant reactor produced ~320 g ZnS without process optimization or replacement of used medium; this quantity would be sufficient to form a ZnS thin film with ~120 nm thickness over 0.5 m width × 13 km length. At all scales, the bacteria produced significant amounts of acetic, lactic, and formic acids, which could be neutralized by the controlled addition of sodium hydroxide without the use of an organic pH buffer, eliminating 98 % of the buffer chemical costs. The final NP products were characterized using XRD, ICP-OES, TEM, FTIR, PL, DLS, HPLC, and C/N analyses, which confirmed that the growth medium without organic buffer enhanced the ZnS NP properties by reducing carbon and nitrogen surface coatings and supporting better dispersivity with similar ACS.
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Nanopartículas/metabolismo , Sulfuros/metabolismo , Thermoanaerobacter/metabolismo , Compuestos de Zinc/metabolismo , Anaerobiosis , Concentración de Iones de HidrógenoRESUMEN
In the developing field of printed electronics, nanoparticle based inks such as CuO show great promise as a low-cost alternative to other metal-based counterparts (e.g., silver). In particular, CuO inks significantly eliminate the issue of particle oxidation before and during the sintering process that is prevalent in Cu-based formulations. We report here the scalable and low-thermal-budget photonic fabrication of Cu interconnects employing a roll-to-roll (R2R)-compatible pulse-thermal-processing (PTP) technique that enables phase reduction and subsequent sintering of ink-jet-printed CuO patterns onto flexible polymer templates. Detailed investigations of curing and sintering conditions were performed to understand the impact of PTP system conditions on the electrical performance of the Cu patterns. Specifically, the impact of energy and power of photonic pulses on print conductivity was systematically studied by varying the following key processing parameters: pulse intensity, duration, and sequence. Through optimization of such parameters, highly conductive prints were obtained in <1 s with resistivity values as low as 10 µΩ cm (corresponding to â¼17% of the International Annealed Copper Standard (IACS) conductivity) was achieved. It was also observed that the introduction of an initial ink-drying step in ambient atmosphere, after the printing and before sintering, leads to significant improvements in mechanical integrity and electrical performance of the printed Cu patterns. Moreover, the viability of CuO reactive inks, coupled with the PTP technology and pre-sintering ink-drying protocols, has also been demonstrated for the additive integration of a low-cost Cu temperature sensor onto a flexible polymer substrate.
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A two-step solution processing approach has been established to grow void-free perovskite films for low-cost high-performance planar heterojunction photovoltaic devices. A high-temperature thermal annealing treatment was applied to drive the diffusion of CH3NH3I precursor molecules into a compact PbI2 layer to form perovskite films. However, thermal annealing for extended periods led to degraded device performance owing to the defects generated by decomposition of perovskite into PbI2. A controllable layer-by-layer spin-coating method was used to grow "bilayer" CH3NH3I/PbI2 films, and then drive the interdiffusion between PbI2 and CH3NH3I layers by a simple air exposure at room temperature for making well-oriented, highly crystalline perovskite films without thermal annealing. This high degree of crystallinity resulted in a carrier diffusion length of ca. 800â nm and a high device efficiency of 15.6%, which is comparable to values reported for thermally annealed perovskite films.
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Structural characteristics of the active layers in organic photovoltaic (OPV) devices play a critical role in charge generation, separation and transport. Here we report on morphology and structural control of p-DTS(FBTTh2)2:PC71BM films by means of thermal annealing and 1,8-diiodooctane (DIO) solvent additive processing, and correlate it to the device performance. By combining surface imaging with nanoscale depth-sensitive neutron reflectometry (NR) and X-ray diffraction, three-dimensional morphologies of the films are reconstituted with information extending length scales from nanometers to microns. DIO promotes the formation of a well-mixed donor-acceptor vertical phase morphology with a large population of small p-DTS(FBTTh2)2 nanocrystals arranged in an elongated domain network of the film, thereby enhancing the device performance. In contrast, films without DIO exhibit three-sublayer vertical phase morphology with phase separation in agglomerated domains. Our findings are supported by thermodynamic description based on the Flory-Huggins theory with quantitative evaluation of pairwise interaction parameters that explain the morphological changes resulting from thermal and solvent treatments. Our study reveals that vertical phase morphology of small-molecule based OPVs is significantly different from polymer-based systems. The significant enhancement of morphology and information obtained from theoretical modeling may aid in developing an optimized morphology to enhance device performance for OPVs.
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Advances in material design and device engineering led to inverted organic solar cells (i-OSCs) with superior power conversion efficiencies (PCEs) compared to their "conventional" counterparts, in addition to the well-known better ambient stability. Here, we report an in-depth morphology study of the i-OSC active and cathode modifying layers, employing a model system with a well-established bulk-heterojunction, PTB7:PC71BM as the active layer and poly-[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) as the cathode surface modifying layer. We have also identified the role of a processing additive, 1,8-diiodooctane (DIO), used in the spin-casting of the active layer to increase PCE. Using various characterization techniques, we demonstrate that the high PCEs of i-OSCs are due to the diffusion of electron-accepting PC71BM into the PFN layer, resulting in improved electron transport. The diffusion occurs when residual solvent molecules in the spun-cast film act as a plasticizer. Addition of DIO to the casting solution results in more PC71BM diffusion and therefore more efficient electron transport. This work provides important insight and guidance to further enhancement of i-OSC performance by materials and interface engineering.
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Metal monochalcogenide quantum dot nanocrystals of ZnS, CdS and SnS were prepared by anaerobic, metal-reducing bacteria using in situ capping by oleic acid or oleylamine. The capping agent preferentially adsorbs on the surface of the nanocrystal, suppressing the growth process in the early stages, thus leading to production of nanocrystals with a diameter of less than 5 nm.
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Bacterias Anaerobias , Nanopartículas del Metal/microbiología , Puntos Cuánticos/microbiología , Aminas/química , Compuestos de Cadmio/química , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Ácido Oléico/química , Tamaño de la Partícula , Puntos Cuánticos/química , Puntos Cuánticos/ultraestructura , Sulfuros/química , Propiedades de Superficie , Compuestos de Estaño/química , Compuestos de Zinc/químicaRESUMEN
A series of semiconducting zinc sulfide (ZnS) nanoparticles were scalably, reproducibly, controllably and economically synthesized with anaerobic metal-reducing Thermoanaerobacter species. These bacteria reduced partially oxidized sulfur sources to sulfides that extracellularly and thermodynamically incorporated with zinc ions to produce sparingly soluble ZnS nanoparticles with â¼5nm crystallites at yields of â¼5gl(-1)month(-1). A predominant sphalerite formation was facilitated by rapid precipitation kinetics, a low cation/anion ratio and a higher zinc concentration compared to background to produce a naturally occurring hexagonal form at the low temperature, and/or water adsorption in aqueous conditions. The sphalerite ZnS nanoparticles exhibited narrow size distribution, high emission intensity and few native defects. Scale-up and emission tunability using copper doping were confirmed spectroscopically. Surface characterization was determined using Fourier transform infrared and X-ray photoelectron spectroscopies, which confirmed amino acid as proteins and bacterial fermentation end products not only maintaining a nano-dimensional average crystallite size, but also increasing aggregation. The application of ZnS nanoparticle ink to a functional thin film was successfully tested for potential future applications.
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Membranas Artificiales , Nanopartículas/química , Semiconductores , Sulfuros/química , Thermoanaerobacter/química , Compuestos de Zinc/química , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Thermoanaerobacter/metabolismoRESUMEN
Many scholars question the immense variation in rates of mental health outcomes across disaster studies. This study explains this variation by putting forward 2 methodological problems that are inherent to the effect of a disaster context on mental health screening scores. The Hopkins Symptom Checklist-25 was administered in a flood-affected group (n = 318) and a nonaffected group (n = 304) in Uttar Pradesh, India. The affected group showed much higher mean scores on subscales of anxiety and depression. However, factor analyses (i.e., confirmatory factor analyses [CFA] and multilevel confirmatory factor analyses [MCFA]; Muthén, 1994) revealed 2 methodological phenomena that account for the differences in scores. First, the outcomes revealed that a large proportion of covariance between observed mental health variables did not refer to the latent concepts of interest (depression and anxiety), but to the context of both groups (disaster affected vs. nonaffected). The shared effect of the disaster on the context explained a large proportion of the covariances between the items and biased outcomes. Second, after dissecting this group variance, the construct validity of the assessments of anxiety and depression was revealed to be poor and unstable across both groups. The subscales of anxiety and depression referred to different concepts in both groups. These 2 methodological problems have not been discussed thus far, but they contribute to the variation in mental health outcomes across disaster studies.
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Ansiedad/diagnóstico , Depresión/diagnóstico , Escalas de Valoración Psiquiátrica/normas , Sobrevivientes/psicología , Adulto , Ansiedad/etiología , Depresión/etiología , Desastres , Análisis Factorial , Femenino , Inundaciones , Humanos , Masculino , Persona de Mediana EdadRESUMEN
INTRODUCTION: Very little is known on the impact of recurrent disasters on mental health. Aim The present study examines the immediate impact of a recurrent flood on mental health and functioning among an affected population in the rural district of Bahraich, Uttar Pradesh, India, compared with a population in the same region that is not affected by floods. METHODS: The study compared 318 affected respondents with 308 individuals who were not affected by floods. Symptoms of anxiety and depression were assessed by the Hopkins Symptom Checklist-25 (HSCL-25). Psychological and physical functioning was assessed by using the Short Form-12 (SF-12). RESULTS: The affected group showed large to very large differences with the comparison group on symptoms of anxiety (D = .92) and depression (D = 1.22). The affected group scored significantly lower on psychological and physical functioning than the comparison group (respectively D = .33 and D = .80). However, hierarchical linear regressions showed no significant relationship between mental health and the domains of functioning in the affected group, whereas mental health and the domains of functioning were significantly related in the comparison group. CONCLUSION: This study found a large negative impact of the recurrent floods on mental health outcomes and psychological and physical functioning. However, in a context with recurrent floods, disaster mental health status is not a relevant predictor of functioning. The findings suggest that the observed mental health status and impaired functioning in this context are also outcomes of another mechanism: Both outcomes are likely to be related to the erosion of the social and environmental and material context. As such, the findings refer to a need to implement psychosocial context-oriented interventions to address the erosion of the context rather than specific mental health interventions.
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Desastres/estadística & datos numéricos , Inundaciones/estadística & datos numéricos , Salud Mental , Adulto , Análisis Factorial , Femenino , Indicadores de Salud , Humanos , India , Masculino , Persona de Mediana Edad , Estaciones del AñoRESUMEN
BACKGROUND: Diarrhea is an important problem among the under-five children in India. OBJECTIVE: The paper examines long-term impacts of recurrent floods on diarrhea among under-five children in Uttar Pradesh, India. DESIGN: A two stage stratified cluster survey was conducted in flood affected (exposed) and non-flood affected areas (unexposed). RESULTS: The long-term impact of the floods was not clearly marked in the overall prevalence of diarrhea with the exposed group having prevalence of 55.1% as against 56.2% in the unexposed group of children under five. Economic condition of the household is associated with the prevalence of diarrhea in both exposed and unexposed strata. Anemia was found to be a significant risk factor for diarrhea among children in both the flood exposed and non-flood exposed populations. The recurrent floods did not have any significant effect on the prevalence of diarrhea in relation to gender, religion, caste, and household size. CONCLUSIONS: The study indicates that the long-term impacts of floods are very differently manifested than the immediate impacts.