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In this study, we examine multiple perspectives on soliton solutions to the (3+1)-dimensional Boussinesq model by applying the unified Riccati equation expansion (UREE) approach. The Boussinesq model examines wave propagation in shallow water, which is derived from the fluid dynamics of a dynamical system. The UREE approach allows us to derive a range of distinct solutions, such as single, periodic, dark, and rational wave solutions. Furthermore, we present the bifurcation, chaotic, and sensitivity analysis of the proposed model. We use planar dynamical system theory to analyze the structure and characteristics of the system’s phase portraits. The current study depends on a dynamic structure that has novel and unexplored results for this model. In addition, we display the behaviors of associated physical models in 3-dimensional, density, and 2-dimensional graphical structures. Our findings demonstrate that the UREE technique is a valuable mathematical tool in engineering and applied mathematics for studying wave propagation in nonlinear evolution equations. [ABSTRACT FROM AUTHOR]

In nature, symmetry is all around us. The symmetry framework represents integer partial differential equations and their fractional order in the sense of Caputo derivatives. This article suggests a semi-analytical approach based on Aboodh transform (A T) and the homotopy perturbation scheme (HPS) for achieving the approximate solution of time-fractional porous media and heat transfer equations. The A T converts the fractional problems into simple ones and obtains the recurrence relation without any discretization or assumption. This nonlinear recurrence relation can be decomposed via the use of the HPS to obtain the iterations in terms of series solutions. The initial conditions play an important role in determining the successive iterations and yields towards the exact solution. We provide some numerical applications to analyze the accuracy of this proposed scheme and show that the performance of our scheme has strong agreement with the exact results. [ABSTRACT FROM AUTHOR]

• Childhood exposure to violent conflict has lasting impact on social preferences. • Males and females have strikingly contrasting responses to more intense exposure. • Females become pro-social – higher trust, trustworthiness, public good contribution. • Males become anti-social – tendency to destroy other participants' money. • Age of exposure and intensity of riots are predictors of stronger impacts. We examine gender differences in the long-term impact of childhood exposure to violent conflict on a range of behavioral traits by conducting a large-scale field experiment in the Indian state of Assam, which witnessed fatal ethnic riots in the early 1980s. We exploit an individual's geographic location and age at exposure to riots to examine the effects of varied exposure to violent conflict during childhood and early adolescence on their pro- and antisocial behavior, as well as their risk and time preferences. The results suggest that, as the intensity of exposure to riots during childhood increases, females show more prosocial behavior, whereas males demonstrate a higher degree of antisocial behavior. Our study offers important insights into the divergent effects of conflict by gender. [ABSTRACT FROM AUTHOR]

• Patients statistically discriminate doctors by gender in an experiment in India • Caste quotas for college seats increase gender discrimination of low-caste doctors • Caste quotas for college seats reduce gender discrimination of high-caste doctors • Caste quotas for college seats worsen overall gender inequality of professionals Using a field experiment in India where patients are randomly assigned to rank among a set of physicians of the same gender but with different castes and years of experience, we show that the differences in patients' physician choices are consistent with gender-based statistical discrimination. Labor market experience cannot easily overcome the discrimination that female doctors suffer. Further, we find that gender discrimination is greater for lower caste doctors, who typically suffer from caste discrimination. Given the increasing share of professionals from a lower caste background, our results suggest that the 'intersectionality' between gender and caste leads to increased gender inequality among professionals in India. [ABSTRACT FROM AUTHOR]

The paper shows the effect of the probe on the performance of a transonic axial speed compressor. The unobstructed flow case with the experimental data was validated and used as a guide for all subsequent study cases. The aerodynamic performance for different probe parameters were calculated numerically using ANSYS-CFX. This covered the results on compressor output from changing probe axial positions, the radial immersion depths, the size of the probe, and the total number of probes. The findings were evaluated in relation to the total pressure ratio, performance, margin of deflation and stability. The velocity part distributions further showed that the probe block and raises the flow Mach value, which is the explanation why the compressor rotor's total pressure ratio is lost. In fact, the parameters of the sample will significantly influence the calculation outcomes and affect the standard margin. The range of stability was also affected, which changes the performance trend from the choke to the stall. Consequently, the collection of correct probe parameters with fewer impact on compressor output is addressed. [ABSTRACT FROM AUTHOR]

We conduct an experiment to examine gender bias in intra-household decision-making in rural Bangladesh. The experiment mimics a real-life scenario, in which a risky choice with high stakes is offered to either spouse and he/she then has to decide whether to make the decision or transfer it to the other spouse. We then observe the decision-making process under alternative experimental conditions to determine intra-household gender bias. We find that women are more likely to allow their spouses to make decisions than men are. Our findings suggest that women's transfer decisions are driven by asymmetries in both power and perceived financial capabilities. [ABSTRACT FROM AUTHOR]

We examine the labour market and human capital investment behaviour of immigrant couples in Australia. The family investment hypothesis (FIH) states that immigrant husbands, whom the FIH assumes to be the primary earners in the family, will invest more in their human capital than immigrant wives, whom the FIH assumes to be secondary earners. Using longitudinal data from Household, Income and Labour Dynamics in Australia (HILDA) for the period 2001 to 2014, we do not find support for the FIH. Instead, we find that foreign‐born husbands and wives share similar labour market assimilation patterns with respect to hours of work and wages. Our estimates suggest that immigrant wives' labour market behaviour can be better explained by their own long‐term career progression and labour market assimilation, than through supporting their husbands' labour market assimilation. [ABSTRACT FROM AUTHOR]

• We study the effects of random dormitory assignment. • We find that peer ability effects are around one-third of one's own ability. • High-ability students gain more from higher-ability peers. • Assortative matching on ability but asymmetric matching on background works better. We study the effect of random dormitory assignment in a tertiary level educational institution in India on students' subsequent academic achievements. We examine the importance of interactions between the characteristics of the student and his peers for educational outcomes, including non-linear peer-effects and the importance of different socio-economic and geographical backgrounds. We find that peer ability effects are around one-third the size of the effects of one's own ability, and students from non-urban and non-English backgrounds do particularly better when assigned to higher-ability peers. We find that all groups of ability students gain from being matched to high-ability peers, but that this gain is highest for students who are themselves of higher-ability. Our results suggest peer effects are stronger in the first year in dorm. In terms of mechanisms, we find no evidence for effects of peers via mental health, life satisfaction, or risk attitudes. We observe that a roommate's study times is highly correlated with a student's own study times, but we see only a weak positive association between study habits and grades. [ABSTRACT FROM AUTHOR]

In this paper, we suggest a modification for the residual power series method that is used to solve fractional-order Helmholtz equations, which is called the Shehu-transform residual power series method (S T-RPSM). This scheme uses a combination of the Shehu transform (S T) and the residual power series method (RPSM). The fractional derivatives are taken with respect to Caputo order. The novelty of this approach is that it does not restrict the fractional order and reduces the need for heavy computational work. The results were obtained using an iterative series that led to an exact solution. The 3D graphical plots for different values of fractional orders are shown to compare S T-RPSM results with exact solutions. [ABSTRACT FROM AUTHOR]

Natural disasters frequently occur across both developed and developing countries. The vast majority of lives that are lost and affected by natural disasters are from poor areas in developing countries. We examine the post-disaster recovery of the households in rural Bangladesh that were affected by Cyclone Aila from 2009 to 2010. Exploiting exogenous variations in households' exposure to the disaster within the village, we provide empirical evidence of resource sharing within the households' informal network of neighbors and relatives to assist in recovery from the natural disaster. We find a household's own exposure to the disaster had no significant effect on its investment and income; however, exposure to a household's network had a significant effect on household investment and income two years and six months after the cyclone. We find that informal resource sharing within a household's network crowded out the household's need to purchase formal insurance against disasters. [ABSTRACT FROM AUTHOR]

We examine the effects of the schooling of girls on the education of their younger siblings. To examine the causal effect of the education of older children on their younger siblings, we use the introduction of a gender-targeted conditional cash transfer program – the Female Secondary School Stipend Program (FSSSP) in Bangladesh. We find that an additional year of schooling of older siblings increases schooling of their younger siblings by 0.13 years. The stipend program accounts for about a 10 per cent increase in the schooling of younger siblings. The results suggest that stipend programs can bring both short- and long-term gains, not only via direct benefits to affected children, but also via indirect benefits to their siblings. [ABSTRACT FROM PUBLISHER]

• We examine the long-term effects of exposure to genocide during childhood. • We distinguish between directly-exposed and indirectly-exposed individuals. • Directly-exposed individuals become more antisocial as death rates increase. • Directly-exposed individuals become more risk taking as death rates increase. • Results suggest the direct exposure channel drives the long-term effects. We conduct an artefactual field experiment to examine the long-term effects of exposure to violence due to the Cambodian genocide (1975–1979), during childhood and adolescence, on individuals' antisocial behaviors. Since antisocial behavior can co-exist with other preferences, we also investigate the effect of this exposure on prosocial and risk-taking behaviors. We find that as district-level mortality rates increase, individuals who directly experienced violence during the genocide period exhibit greater antisocial and risk-taking behaviors decades later. These effects are relatively muted among individuals who did not directly experience genocidal violence. The results imply significant long-term effects on antisocial and risk preferences in association with direct exposure to genocidal violence. [ABSTRACT FROM AUTHOR]

We investigate wage differential by migrant status across white-collar and blue-collar occupations in Australia. Migrants are observed to have a higher wage; this difference, however, does not exist once we control for covariates. The unconditional wage differential varies over wage distribution as well as by occupation. Significant wage differentials are found above the median: positive for white-collar workers and negative for blue-collar workers. Using recently developed decomposition methods based on Firpo, Fortin, and Lemieux (2009) we decompose wage differentials across their distribution. Overall, the wage advantage of migrants reflects their superior labour market characteristics, and in particular, their levels of education. We find that English language proficiency plays an important role in wage differences among immigrants from non-English speaking countries. [ABSTRACT FROM AUTHOR]

we propose an embedded, block-based, image wavelet transform coding algorithm of low complexity. it uses a recursive set-partitioning procedure to sort subsets of wavelet coefficients by maximum magnitude with respect to thresholds that are integer powers of two. It exploits two fundamental chars acteristics of an image transform-the well-defined hierarchical structure, and energy clustering in frequency and in space. The two partition strategies allow for versatile and efficient coding of several image transform structures, including dyadic, blocks inside subbands, wavelet packets, and discrete cosine transform (DCT). We describe the use of this coding algorithm in several implementations, including reversible (lossless) coding and its adaptation for color images, and show extensive comparisons with other state-of-the-an coders, such as set partitioning in hierarchical trees (SPIlT) and JPEG2000, We conclude that this algorithm, in addition to being very flexible, retains alt the desirable features of these algorithms and is highly competitive to them in compression efficiency. [ABSTRACT FROM AUTHOR]

A hidden cost of the COVID-19 pandemic is the stigma associated with the disease for those infected and groups that are considered as more likely to be infected. This paper examines whether the provision of accurate and focused information about COVID-19 from a reliable source can reduce stigmatization. We carry out a randomized field experiment in the state of Uttar Pradesh, India, in which we provide an information brief about COVID-19 by phone to a random subsample of participants to address stigma and misconceptions. We find that the information brief decreases stigmatization of COVID-19 patients and certain groups such as religious minorities, lower-caste groups, and frontline workers (healthcare, police), and reduces the belief that infection cases are more prevalent among certain marginalized social and economic groups (Muslims, low caste, rural-poor population). We provide suggestive evidence that improved knowledge about the prevention and transmission of COVID-19 and reduced stress about the disease are important channels for the reduction in stigmatization. • We carried out a randomized field experiment in the state of Uttar Pradesh, India. • A random subsample of participants received an information brief about COVID-19. • Accurate and focused information about COVID-19 reduces stigmatization. • The information also reduces biased beliefs about outgroups. • Improved knowledge and reduced stress are important channels for the effects. [ABSTRACT FROM AUTHOR]

• We examine food insecurity situation during COVID-19 in rural Bangladesh. • 90% of households experienced loss of income due to lockdown. • COVID-19 led to a drastic increase in income loss and food insecurity. • Farm and day laborers were initially affected the most. • Food insecurity increased significantly over time. COVID-19 has threatened food security of the poor due to the lockdown of markets amidst poor institutions and lack of social safety nets in the developing world. To provide rapid evidence on the determinants and dynamics of food insecurity and to understand the coping strategies adopted by rural households during the pandemic, we carried out a telephone survey of roughly 10,000 rural households in Bangladesh, three weeks after the country went into lockdown. We found that roughly 90% of households reported experiencing a negative income shock after the countrywide lockdown was implemented. Households that primarily depend on daily casual labor for their income were affected the most, while households with regular jobs were affected the least in terms of food insecurity. Households adversely hit by income shock due to the pandemic were also found to rely more on past savings, food stocks, and loans from various sources to cope with the food crisis. When we followed-up 2402 households, about 3 to 4 weeks after the first survey, to understand the dynamics of food insecurity, we found that food insecurity increased significantly across households and began affecting groups that were in an advantageous position during the first survey. This poses a threat to the poor as food security has already worsened since the crisis hit and would presumably worsen further in the future unless rapid measures are taken to attenuate it at the earliest. [ABSTRACT FROM AUTHOR]

The flow of an electrically conducting micropolar fluid with a radiative heat source and mixed chemically reactive species is considered. The stretching/shrinking surface under the influence of the applied magnetic field in the normal direction is used. Appropriate similarity functions are used for the numerical solution of highly non-linear governing equations of the flow problem, and the behaviors of the flow, temperature and concentration function under the influence of various physical parameters are revealed graphically. [ABSTRACT FROM AUTHOR]

Survey measures of risk attitudes are primarily used in the health literature, although incentivized measures of risk preferences are being increasingly used in other fields. We exploit the unique setting of commercial female sex workers in Bangladesh to investigate whether incentivized measures of risk preferences, or non-incentivized survey measures of risk preferences, best identify the risky commercial sex decisions that they make. The study uses survey data collected during February–April 2016, and October–November 2016 from eight brothels in Bangladesh. Wave 1 includes 1,332 female sex workers, Wave 2 includes 1,185 female sex workers. Our findings suggest that researchers can reliably use survey measures to elicit risk preferences on health. • We investigate risk preferences of commercial sex workers. • Survey measures of health risk attitudes better predict the risky sexual transaction. • Financial risk attitudes do not predict well in unprotected sexual transaction. [ABSTRACT FROM AUTHOR]

Progressing advancement concerning the intensification of engine thrust to weight ratio in a gas turbine engine offers ascends to extremely loaded compressor stages which have a significant concern in recent times. Non-uniform Inlet flow conditions are frequently occurring in aircraft gas turbines engines that result in chronological distortions of total temperature and total pressure at the engine inlet. Distorted inlet flow operation of the axial compressor deteriorates the aerodynamic performance which reduces stall margin and increased blade stress levels. The current paper aims at the investigation of the flow field in the tip clearance region of the transonic micro-axial flow compressor at non-uniform flow conditions. Under the design and off-design RPM, the current paper focuses on the adverse effects of a steady-state distorted pattern of total pressure inlet flow conditions, including hub radial, tip radial pressure distortion, and combined effects of pressure distortion with bulk swirl flow to evaluate its effects on compressor performance and stability. The results show that like hub radial pressure distortion improves the stability range of turbofan transonic micro-compressor rotor. Whereas tip radial and counter swirl flow deteriorate the performance of the compressor. Furthermore, compressor performance alleviated the stall at higher RPM combined with distorted inlet pressure. [ABSTRACT FROM AUTHOR]

This paper demonstrates an effective and powerful technique, namely fractional He–Laplace method (FHe-LM), to study a nonlinear coupled system of equations with time fractional derivative. The FHe-LM is designed on the basis of Laplace transform to elucidate the solution of nonlinear fractional Hirota–Satsuma coupled KdV and coupled mKdV system but the series coefficients are evaluated in an iterative process with the help of homotopy perturbation method manipulating He's polynomials. The fractional derivatives are considered in the Caputo sense. The obtained results confirm the suggested approach is extremely convenient and applicable to provide the solution of nonlinear models in the form of a convergent series, without any restriction. Also, graphical representation and the error estimate when compared with the exact solution are presented. [ABSTRACT FROM AUTHOR]

Background: This study examines the association between food insecurity and mental health of women during the COVID-19 pandemic in a resource poor setting. Materials and methods: Data were collected at two time-points (wave 1 and 2) from 2402 women, one per household, participating in a larger study during extended COVID-19 lockdown in the rural areas of the southwest region of Bangladesh. The primary outcome of the analyses is the association between food insecurity, measured using the Food Insecurity Experience Scale (FIES), and stress level, measured using the Perceived Stress Scale (PSS), for women during the lockdown. General awareness about COVID-19 and attitude towards prescribed preventive measures were also measured since COVID-19 health concerns could exacerbate food insecurity. Results: An individual-level evaluation of the effect of wave 2 FIES score on PSS score showed that worsening of the food security status increasing the stress level of the participants (95% CI: 1.61; 2.13; p-value: <0.001). Additionally, a significant negative association was observed between the PSS score and change in food security status between the two waves (Coefficient: -1.15, 95% CI: -1.30; -0.99, p-value: <0.001), indicating that deterioration in food security status over the pandemic period increasing the stress level. At the village level, the results showed a similar pattern. General awareness around ways coronavirus spreads was high, yet there were misperceptions at a higher level. Maintaining hand hygiene, wearing face masks outside the home, and going outside only when necessary were widely practised. Fewer respondents could maintain a 1.5-metre distance from others in the outside and maintained cough and sneeze etiquette. Conclusion: The results indicate a higher stress level, a potential contributor to poor mental health, as food insecurity deteriorated. Policy initiatives in ameliorating immediate food insecurity during crises, improving long-term wellbeing, and expanding the reach of mental health support are warranted. [ABSTRACT FROM AUTHOR]

Background: The Coronavirus Disease 2019 (COVID-19) pandemic and associated mitigation policies created a global economic and health crisis of unprecedented depth and scale, raising the estimated prevalence of depression by more than a quarter in high-income countries. Low- and middle-income countries (LMICs) suffered the negative effects on living standards the most severely. However, the consequences of the pandemic for mental health in LMICs have received less attention. Therefore, this study assesses the association between the COVID-19 crisis and mental health in 8 LMICs. Methods and findings: We conducted a prospective cohort study to examine the correlation between the COVID-19 pandemic and mental health in 10 populations from 8 LMICs in Asia, Africa, and South America. The analysis included 21,162 individuals (mean age 38.01 years, 64% female) who were interviewed at least once pre- as well as post-pandemic. The total number of survey waves ranged from 2 to 17 (mean 7.1). Our individual-level primary outcome measure was based on validated screening tools for depression and a weighted index of depression questions, dependent on the sample. Sample-specific estimates and 95% confidence intervals (CIs) for the association between COVID-19 periods and mental health were estimated using linear regressions with individual fixed effects, controlling for independent time trends and seasonal variation in mental health where possible. In addition, a regression discontinuity design was used for the samples with multiple surveys conducted just before and after the onset of the pandemic. We aggregated sample-specific coefficients using a random-effects model, distinguishing between estimates for the short (0 to 4 months) and longer term (4+ months). The random-effects aggregation showed that depression symptoms are associated with a increase by 0.29 standard deviations (SDs) (95% CI [−.47, −.11], p-value = 0.002) in the 4 months following the onset of the pandemic. This change was equivalent to moving from the 50th to the 63rd percentile in our median sample. Although aggregate depression is correlated with a decline to 0.21 SD (95% CI [−0.07, −.34], p-value = 0.003) in the period thereafter, the average recovery of 0.07 SD (95% CI [−0.09,.22], p-value = 0.41) was not statistically significant. The observed trends were consistent across countries and robust to alternative specifications. Two limitations of our study are that not all samples are representative of the national population, and the mental health measures differ across samples. Conclusions: Controlling for seasonality, we documented a large, significant, negative association of the pandemic on mental health, especially during the early months of lockdown. The magnitude is comparable (but opposite) to the effects of cash transfers and multifaceted antipoverty programs on mental health in LMICs. Absent policy interventions, the pandemic could be associated with a lasting legacy of depression, particularly in settings with limited mental health support services, such as in many LMICs. We also demonstrated that mental health fluctuates with agricultural crop cycles, deteriorating during "lean", pre-harvest periods and recovering thereafter. Ignoring such seasonal variations in mental health may lead to unreliable inferences about the association between the pandemic and mental health. Nursena Aksunger and colleagues investigate the association between the COVID-19 pandemic and mental health in eight low- and middle-income countries. Author summary: Why was this study done?: The worldwide economic and health crises triggered by the Coronavirus Disease 2019 (COVID-19) pandemic have had a significant influence on mental health, with the estimated prevalence of depression having increased by more than 25% in high-income countries. Although the adverse consequences of the pandemic on living standards have been most severe in low- and middle-income countries (LMICs), the consequences of the pandemic for mental health in LMICs have received less attention. What did the researchers do and find?: The purpose of this research is to investigate the association between the COVID-19 pandemic and mental health in 8 LMICs in Asia, Africa, and South America. Before and during the pandemic, the mental health of 21,162 individuals (mean age 38.01 years, 64.0% female) was measured using survey data. Our individual-level primary outcome measure was based on validated depression screening instruments and a sample-specific weighted index of depression questions. We found that depression symptoms were associated with a significant increase in the 4 months following the onset of the pandemic (0.29 standard deviations (SDs), 95% confidence interval (CI) [−.47, −.11], p-value = 0.002) and that the average recovery of 0.07 SD was not statistically significant in the subsequent period (95% CI [−0.09,.22], p-value = 0.41). What do these findings mean?: We showed a substantial negative correlation between the COVID-19 pandemic and mental health after adjusting for seasonality, suggesting that the pandemic might induce long-term depression, especially in LMICs with poor mental health support facilities. We also provided evidence for seasonal changes in mental health depending on agricultural crop cycle. This seasonality should be considered when examining changes in mental health over time in order to prevent drawing inaccurate conclusions. The observed trends were consistent across countries and robust to alternative analyses, although the study was limited by the fact that not all samples were representative of the national population and the mental health indicators differed among samples. [ABSTRACT FROM AUTHOR]

Video content creation and production has reached the masses as almost everyone is now able to create video clips on a daily basis. Video editing is a natural and necessary operation that is most commonly employed by users after video capture. Wireless imaging and video capturing devices, with hardware constraints of memory and processing power, are unable to accommodate conventional spatial domain video editing. In this paper we present a set of algorithms for efficiently performing editing effects on video content. The proposed algorithms, covering intra and inter sequence operations, are applied on H.263 and MPEG-4 compressed video sequences. The techniques ensure that the desired effects are achieved generating standard compliant codestreams, with significant savings in computations compared to the convention approach based on spatial domain editing. [ABSTRACT FROM AUTHOR]

To process or introduce editing effects on JPEG2000 images, we propose techniques applying these operations in the compressed domain. Our approach exploits the properties of the wavelet transform and the rich bitstream syntax of the JPEG2000 standard. The suggested techniques provide significant speed-ups compared to the conventional methods based on spatial domain processing of the decoded images. [ABSTRACT FROM AUTHOR]

The Epi Info Viral Hemorrhagic Fever application (Epi Info VHF) was developed in response to challenges managing outbreak data during four 2012 filovirus outbreaks. Development goals included combining case and contact data in a relational database, facilitating data-driven contact tracing, and improving outbreak data consistency and use. The application was first deployed in Guinea, when theWest Africa Ebola epidemic was detected, in March 2014, and has been used in 7 African countries and 2 US states. Epi Info VHF enabled reporting of compatible data from multiple countries, contributing to international Ebola knowledge. However, challenges were encountered in accommodating the epidemic′s unexpectedly large magnitude, addressing country-specific needs within 1 software product, and using the application in settings with limited Internet access and information technology support. Use of Epi Info VHF in theWest Africa Ebola epidemic highlighted the fundamental importance of good data management for effective outbreak response, regardless of the software used. [ABSTRACT FROM AUTHOR]