874 research outputs found
Maze solvers demystified and some other thoughts
There is a growing interest towards implementation of maze solving in
spatially-extended physical, chemical and living systems. Several reports of
prototypes attracted great publicity, e.g. maze solving with slime mould and
epithelial cells, maze navigating droplets. We show that most prototypes
utilise one of two phenomena: a shortest path in a maze is a path of the least
resistance for fluid and current flow, and a shortest path is a path of the
steepest gradient of chemoattractants. We discuss that substrates with
so-called maze-solving capabilities simply trace flow currents or chemical
diffusion gradients. We illustrate our thoughts with a model of flow and
experiments with slime mould. The chapter ends with a discussion of experiments
on maze solving with plant roots and leeches which show limitations of the
chemical diffusion maze-solving approach.Comment: This is a preliminary version of the chapter to be published in
Adamatzky A. (Ed.) Shortest path solvers. From software to wetware. Springer,
201
Participatory women’s groups and counseling through home visits to improve child growth in rural eastern India: protocol for a cluster randomised controlled trial
Background: Childhood stunting (low height-for-age) is a marker of chronic undernutrition and predicts children’s subsequent physical and cognitive development. An estimated 52 million children in India are stunted. There is a broad consensus on determinants of child undernutrition and interventions to address it, but a lack of operational research testing strategies to increase the coverage of these interventions in high burden areas. Our study aims to assess the impact, costeffectiveness, and scalability of a community intervention involving a government-proposed community-based worker to improve growth in children under two
Mortality and recovery following moderate and severe acute malnutrition in children aged 6-18 months in rural Jharkhand and Odisha, eastern India: A cohort study
BACKGROUND: Recent data suggest that case fatality from severe acute malnutrition (SAM) in India may be lower than the 10%-20% estimated by the World Health Organization (WHO). A contemporary quantification of mortality and recovery from acute malnutrition in Indian community settings is essential to inform policy regarding the benefits of scaling up prevention and treatment programmes. METHODS AND FINDINGS: We conducted a cohort study using data collected during a recently completed cluster-randomised controlled trial in 120 geographical clusters with a total population of 121,531 in rural Jharkhand and Odisha, eastern India. Children born between October 1, 2013, and February 10, 2015, and alive at 6 months of age were followed up at 9, 12, and 18 months. We measured the children's anthropometry and asked caregivers whether children had been referred to services for malnutrition in the past 3 months. We determined the incidence and prevalence of moderate acute malnutrition (MAM) and SAM, as well as mortality and recovery at each follow-up. We then used Cox-proportional models to estimate mortality hazard ratios (HRs) for MAM and SAM. In total, 2,869 children were eligible for follow-up at 6 months of age. We knew the vital status of 93% of children (2,669/2,869) at 18 months. There were 2,704 children-years of follow-up time. The incidence of MAM by weight-for-length z score (WLZ) and/or mid-upper arm circumference (MUAC) was 406 (1,098/2,704) per 1,000 children-years. The incidence of SAM by WLZ, MUAC, or oedema was 190 (513/2,704) per 1,000 children-years. There were 36 deaths: 12 among children with MAM and six among children with SAM. Case fatality rates were 1.1% (12/1,098) for MAM and 1.2% (6/513) for SAM. In total, 99% of all children with SAM at 6 months of age (227/230) were alive 3 months later, 40% (92/230) were still SAM, and 18% (41/230) had recovered (WLZ ≥ -2 standard deviation [SD]; MUAC ≥ 12.5; no oedema). The adjusted HRs using all anthropometric indicators were 1.43 (95% CI 0.53-3.87, p = 0.480) for MAM and 2.56 (95% CI 0.99-6.70, p = 0.052) for SAM. Both WLZ < -3 and MUAC ≥ 11.5 and < 12.5 were associated with increased mortality risk (HR: 3.33, 95% CI 1.23-8.99, p = 0.018 and HR: 3.87, 95% CI 1.63-9.18, p = 0.002, respectively). A key limitation of our analysis was missing WLZ or MUAC data at all time points for 2.5% of children, including for two of the 36 children who died. CONCLUSIONS: In rural eastern India, the incidence of acute malnutrition among children older than 6 months was high, but case fatality following SAM was 1.2%, much lower than the 10%-20% estimated by WHO. Case fatality rates below 6% have now been recorded in three other Indian studies. Community treatment using ready-to-use therapeutic food may not avert a substantial number of SAM-related deaths in children aged over 6 months, as mortality in this group is lower than expected. Our findings strengthen the case for prioritising prevention through known health, nutrition, and multisectoral interventions in the first 1,000 days of life, while ensuring access to treatment when prevention fails
Macrophage-derived human resistin is induced in multiple helminth infections and promotes inflammatory monocytes and increased parasite burden.
Parasitic helminth infections can be associated with lifelong morbidity such as immune-mediated organ failure. A better understanding of the host immune response to helminths could provide new avenues to promote parasite clearance and/or alleviate infection-associated morbidity. Murine resistin-like molecules (RELM) exhibit pleiotropic functions following helminth infection including modulating the host immune response; however, the relevance of human RELM proteins in helminth infection is unknown. To examine the function of human resistin (hResistin), we utilized transgenic mice expressing the human resistin gene (hRetnTg+). Following infection with the helminth Nippostrongylus brasiliensis (Nb), hResistin expression was significantly upregulated in infected tissue. Compared to control hRetnTg- mice, hRetnTg+ mice suffered from exacerbated Nb-induced inflammation characterized by weight loss and increased infiltration of inflammatory monocytes in the lung, along with elevated Nb egg burdens and delayed parasite expulsion. Genome-wide transcriptional profiling of the infected tissue revealed that hResistin promoted expression of proinflammatory cytokines and genes downstream of toll-like receptor signaling. Moreover, hResistin preferentially bound lung monocytes, and exogenous treatment of mice with recombinant hResistin promoted monocyte recruitment and proinflammatory cytokine expression. In human studies, increased serum resistin was associated with higher parasite load in individuals infected with soil-transmitted helminths or filarial nematode Wuchereria bancrofti, and was positively correlated with proinflammatory cytokines. Together, these studies identify human resistin as a detrimental factor induced by multiple helminth infections, where it promotes proinflammatory cytokines and impedes parasite clearance. Targeting the resistin/proinflammatory cytokine immune axis may provide new diagnostic or treatment strategies for helminth infection and associated immune-mediated pathology
The barriers and enablers to education among scheduled caste and scheduled tribe adolescent girls in northern Karnataka, South India: A qualitative study
This qualitative study explored the barriers and enablers to scheduled caste/scheduled tribe (SC/ST) adolescent girls entering into, and completing secondary education in northern Karnataka, South India. In-depth interviews were conducted with 22 adolescent girls, their respective parent/guardian (n = 22) and 11 teachers, recruited purposively from 11 villages within two districts in northern Karnataka. Multiple barriers were identified to disadvantaged caste adolescent girls’ entry into and retention in education in this setting, and these operated at the individual, family, community and school levels. In addition, some enablers to education were also described. The study highlights the importance of involving multiple stakeholders to overcome the barriers to education for SC/ST girls, and of working to change beliefs and expectations around gender norms as well as improving the quality of education in this setting
Magnetic structure and crystal field states of Pr2Pd3Ge5: μSR and neutron scattering investigations
Pursuing Authenticity From Process to Outcome in a Community-Based Participatory Research Study of Intimate Partner Violence and HIV Vulnerability in North Karnataka, India.
Community-based participatory research has been seen to hold great promise by researchers aiming to bridge research and action in global health programs and practice. However, there is still much debate around whether achieving authenticity in terms of in-depth collaboration between community and academic partners is possible while pursuing academic expectations for quality. This article describes the community-based methodology for a qualitative study to explore intimate partner violence and HIV/AIDS among women in sex work, or female sex workers, and their male partners in Karnataka, South India. Developed through collaborative processes, the study methodology followed an interpretive approach to qualitative inquiry, with three key components including long-term partnerships, knowledge exchange, and orientation toward action. We then discuss lessons learned on how to pursue authenticity in terms of truly collaborative processes with inherent value that also contribute to, rather than hinder, the instrumental goal of enhancing the quality and relevance of the research outcomes
Local Optical Probe of Motion and Stress in a multilayer graphene NEMS
Nanoelectromechanical systems (NEMSs) are emerging nanoscale elements at the
crossroads between mechanics, optics and electronics, with significant
potential for actuation and sensing applications. The reduction of dimensions
compared to their micronic counterparts brings new effects including
sensitivity to very low mass, resonant frequencies in the radiofrequency range,
mechanical non-linearities and observation of quantum mechanical effects. An
important issue of NEMS is the understanding of fundamental physical properties
conditioning dissipation mechanisms, known to limit mechanical quality factors
and to induce aging due to material degradation. There is a need for detection
methods tailored for these systems which allow probing motion and stress at the
nanometer scale. Here, we show a non-invasive local optical probe for the
quantitative measurement of motion and stress within a multilayer graphene NEMS
provided by a combination of Fizeau interferences, Raman spectroscopy and
electrostatically actuated mirror. Interferometry provides a calibrated
measurement of the motion, resulting from an actuation ranging from a
quasi-static load up to the mechanical resonance while Raman spectroscopy
allows a purely spectral detection of mechanical resonance at the nanoscale.
Such spectroscopic detection reveals the coupling between a strained
nano-resonator and the energy of an inelastically scattered photon, and thus
offers a new approach for optomechanics
Magnetic structure and field-dependent magnetic phase diagram of Ni2In-type PrCuSi
The magnetic structure of the ternary equiatomic intermetallic compound PrCuSi is investigated using neutron powder diffraction experiments in 0 T as well as in external magnetic fields up to 2 T. The PrCuSi compound crystallizes in the hexagonal Ni2In-type structure, in the space group P63/mmc. In this structure, cationic ordering of Cu and Si takes place. The antiferromagnetic phase transition in the Pr sublattice takes place at K in 0 T. Under an external magnetic field of 2 T, a field-induced ferromagnetic phase is observed. Magnetoelastic coupling is evidenced by an increase in the unit cell volume. Clear signatures of a mixed antiferromagnetic and ferromagnetic phase in weak, intermediate fields, 0.4–0.8 T, are obtained from the present study. Using the present set of experimental data, we construct the H  −  T phase diagram of PrCuSi
Protocol for the economic evaluation of a community-based intervention to improve growth among children under two in rural India (CARING trial)
INTRODUCTION: Undernutrition affects ∼165 million children globally and contributes up to 45% of all child deaths. India has the highest proportion of global undernutrition-related morbidity and mortality. This protocol describes the planned economic evaluation of a community-based intervention to improve growth in children under 2 years of age in two rural districts of eastern India. The intervention is being evaluated through a cluster-randomised controlled trial (cRCT, the CARING trial). METHODS AND ANALYSIS: A cost-effectiveness and cost-utility analysis nested within a cRCT will be conducted from a societal perspective, measuring programme, provider, household and societal costs. Programme costs will be collected prospectively from project accounts using a standardised tool. These will be supplemented with time sheets and key informant interviews to inform the allocation of joint costs. Direct and indirect costs incurred by providers will be collected using key informant interviews and time use surveys. Direct and indirect household costs will be collected prospectively, using time use and consumption surveys. Incremental cost-effectiveness ratios (ICERs) will be calculated for the primary outcome measure, that is, cases of stunting prevented, and other outcomes such as cases of wasting prevented, cases of infant mortality averted, life years saved and disability-adjusted life years (DALYs) averted. Sensitivity analyses will be conducted to assess the robustness of results. ETHICS AND DISSEMINATION: There is a shortage of robust evidence regarding the cost-effectiveness of strategies to improve early child growth. As this economic evaluation is nested within a large scale, cRCT, it will contribute to understanding the fiscal space for investment in early child growth, and the relative (in)efficiency of prioritising resources to this intervention over others to prevent stunting in this and other comparable contexts. The protocol has all necessary ethical approvals and the findings will be disseminated within academia and the wider policy sphere. TRIAL REGISTRATION NUMBER: ISRCTN51505201; pre-results
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