Evidence on the impact of community health workers in the prevention, identification, and management of undernutrition amongst children under the age of five in conflict-affected or fragile settings: a systematic literature review

Background Malnutrition, specifically undernutrition, is a significant global challenge that contributes to nearly half of deaths in children under the age of five. The burden of undernutrition is disproportionately borne by conflict-affected, fragile settings (CAFS); children living in a conflict zone being more than twice as likely to suffer from malnourishment. Community health worker (CHW) models have been employed in CAFS to improve healthcare coverage and identify and treat illnesses. However, there lacks systematic evidence on the impact of CHW models in preventing, identifying, and managing child undernutrition in CAFS. We conducted this review to systematically evaluate evidence of CHW models in preventing, identifying, and managing undernutrition in children under the age of five in CAFS. Methodology This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting standards. The search strategy was developed using the Population-Intervention-Comparisons-Outcomes-Setting framework as a guide. Searches were performed using Ovid online database search platform, searching the databases of Ovid MEDLINE(R), COCHRANE, Embase Classic, Embase, Econlit, Global Health, SCOPUS, and Social Policy and Practice. Peer-reviewed publications were eligible for inclusion if they evaluated an intervention using a CHW model that aims to prevent, identify, or manage some form of undernutrition in children under five in a CAFS. Results We identified 25 studies—spanning 10 countries—that were included in the systematic review. CHW models were implemented alongside a variety of interventions, including behaviour change communication, supplementary foods, nutrition counselling, and integrated community health programmes. Key barriers in implementing successful CHW models include disruption of programmes due to active conflict, states of emergency, militancy, or political unrest; weak links between the community-based interventions and public health system; weak health system capacity that impeded referral and follow-ups; and cost of care and care-seeking. Key facilitators include CHWs’ connection to the community, close proximity of programmes to the community, supervision, and investment in high quality training and tools. Conclusions The findings suggest that CHW models may be effective, cost-effective, acceptable, feasible, and scalable in the prevention, identification, and management child undernutrition in CAFS. The study findings also confirmed a need for greater evidence in the field. These findings may inform policymaking, programme implementation, and design to strengthen best practices for CHW models addressing child undernutrition in CAFS

Non-Gaussianity in the Weak Lensing Correlation Function Likelihood -- Implications for Cosmological Parameter Biases

We study the significance of non-Gaussianity in the likelihood of weak lensing shear two-point correlation functions, detecting significantly non-zero skewness and kurtosis in one-dimensional marginal distributions of shear two-point correlation functions in simulated weak lensing data. We examine the implications in the context of future surveys, in particular LSST, with derivations of how the non-Gaussianity scales with survey area. We show that there is no significant bias in one-dimensional posteriors of $\Omega_{\rm m}$ and $\sigma_{\rm 8}$ due to the non-Gaussian likelihood distributions of shear correlations functions using the mock data ($100$ deg$^{2}$). We also present a systematic approach to constructing approximate multivariate likelihoods with one-dimensional parametric functions by assuming independence or more flexible non-parametric multivariate methods after decorrelating the data points using principal component analysis (PCA). While the use of PCA does not modify the non-Gaussianity of the multivariate likelihood, we find empirically that the one-dimensional marginal sampling distributions of the PCA components exhibit less skewness and kurtosis than the original shear correlation functions.Modeling the likelihood with marginal parametric functions based on the assumption of independence between PCA components thus gives a lower limit for the biases. We further demonstrate that the difference in cosmological parameter constraints between the multivariate Gaussian likelihood model and more complex non-Gaussian likelihood models would be even smaller for an LSST-like survey. In addition, the PCA approach automatically serves as a data compression method, enabling the retention of the majority of the cosmological information while reducing the dimensionality of the data vector by a factor of $\sim$5.Comment: 16 pages, 10 figures, published MNRA

Identifying functional network changing patterns in individuals at clinical high-risk for psychosis and patients with early illness schizophrenia: A group ICA study.

Although individuals at clinical high risk (CHR) for psychosis exhibit a psychosis-risk syndrome involving attenuated forms of the positive symptoms typical of schizophrenia (SZ), it remains unclear whether their resting-state brain intrinsic functional networks (INs) show attenuated or qualitatively distinct patterns of functional dysconnectivity relative to SZ patients. Based on resting-state functional magnetic imaging data from 70 healthy controls (HCs), 53 CHR individuals (among which 41 subjects were antipsychotic medication-naive), and 58 early illness SZ (ESZ) patients (among which 53 patients took antipsychotic medication) within five years of illness onset, we estimated subject-specific INs using a novel group information guided independent component analysis (GIG-ICA) and investigated group differences in INs. We found that when compared to HCs, both CHR and ESZ groups showed significant differences, primarily in default mode, salience, auditory-related, visuospatial, sensory-motor, and parietal INs. Our findings suggest that widespread INs were diversely impacted. More than 25% of voxels in the identified significant discriminative regions (obtained using all 19 possible changing patterns excepting the no-difference pattern) from six of the 15 interrogated INs exhibited monotonically decreasing Z-scores (in INs) from the HC to CHR to ESZ, and the related regions included the left lingual gyrus of two vision-related networks, the right postcentral cortex of the visuospatial network, the left thalamus region of the salience network, the left calcarine region of the fronto-occipital network and fronto-parieto-occipital network. Compared to HCs and CHR individuals, ESZ patients showed both increasing and decreasing connectivity, mainly hypo-connectivity involving 15% of the altered voxels from four INs. The left supplementary motor area from the sensory-motor network and the right inferior occipital gyrus in the vision-related network showed a common abnormality in CHR and ESZ groups. Some brain regions also showed a CHR-unique alteration (primarily the CHR-increasing connectivity). In summary, CHR individuals generally showed intermediate connectivity between HCs and ESZ patients across multiple INs, suggesting that some dysconnectivity patterns evident in ESZ predate psychosis in attenuated form during the psychosis risk stage. Hence, these connectivity measures may serve as possible biomarkers to predict schizophrenia progression

Work-related correlates of occupational sitting in a diverse sample of employees in Midwest metropolitan cities

The worksite serves as an ideal setting to reduce sedentary time. Yet little research has focused on occupational sitting, and few have considered factors beyond the personal or socio-demographic level. The current study i) examined variation in occupational sitting across different occupations, ii) explored whether worksite level factors (e.g., employer size, worksite supports and policies) may be associated with occupational sitting. Between 2012 and 2013, participants residing in four Missouri metropolitan areas were interviewed via telephone and provided information on socio-demographic characteristics, schedule flexibility, occupation, work related factors, and worksite supports and policies. Occupational sitting was self-reported (daily minutes spent sitting at work), and dichotomized. Occupation-stratified analyses were conducted to identify correlates of occupational sitting using multiple logistic regressions. A total of 1668 participants provided completed data. Those employed in business and office/administrative support spent more daily occupational sitting time (median 330 min) compared to service and blue collar employees (median 30 min). Few worksite supports and policies were sitting specific, yet factors such as having a full-time job, larger employer size, schedule flexibility, and stair prompt signage were associated with occupational sitting. For example, larger employer size was associated with higher occupational sitting in health care, education/professional, and service occupations. Work-related factors, worksite supports and policies are associated with occupational sitting. The pattern of association varies among different occupation groups. This exploratory work adds to the body of research on worksite level correlates of occupational sitting. This may provide information on priority venues for targeting highly sedentary occupation groups

Finger-powered fluidic actuation and mixing via MultiJet 3D printing

Additive manufacturing, or three-dimensional (3D) printing, has garnered significant interest in recent years towards the fabrication of sub-millimeter scale devices for an ever-widening array of chemical, biological and biomedical applications. Conventional 3D printed fluidic systems, however, still necessitate the use of non-portable, high-powered external off-chip sources of fluidic actuation, such as electro-mechanical pumps and complex pressure-driven controllers, thus limiting their scope towards point-of-need applications. This work proposes entirely 3D printed sources of human-powered fluidic actuation which can be directly incorporated into the design of any 3D printable sub-millifluidic or microfluidic system where electrical power-free operation is desired. Multiple modular, single-fluid finger-powered actuator (FPA) designs were fabricated and experimentally characterized. Furthermore, a new 3D fluidic one-way valve concept employing a dynamic bracing mechanism was developed, demonstrating a high diodicity of ∼1117.4 and significant reduction in back-flow from the state-of-the-art. As a result, fabricated FPA prototypes achieved tailorable experimental fluid flow rates from ∼100 to ∼3000 μL min−1 without the use of electricity. Moreover, a portable human-powered two-fluid pulsatile fluidic mixer, capable of generating fully-mixed fluids in 10 seconds, is presented, demonstrating the application of FPAs towards on-chip integration into more complex 3D printed fluidic networks

Finger-powered fluidic actuation and mixing via MultiJet 3D printing

Additive manufacturing, or three-dimensional (3D) printing, has garnered significant interest in recent years towards the fabrication of sub-millimeter scale devices for an ever-widening array of chemical, biological and biomedical applications. Conventional 3D printed fluidic systems, however, still necessitate the use of non-portable, high-powered external off-chip sources of fluidic actuation, such as electro-mechanical pumps and complex pressure-driven controllers, thus limiting their scope towards point-of-need applications. This work proposes entirely 3D printed sources of human-powered fluidic actuation which can be directly incorporated into the design of any 3D printable sub-millifluidic or microfluidic system where electrical power-free operation is desired. Multiple modular, single-fluid finger-powered actuator (FPA) designs were fabricated and experimentally characterized. Furthermore, a new 3D fluidic one-way valve concept employing a dynamic bracing mechanism was developed, demonstrating a high diodicity of ∼1117.4 and significant reduction in back-flow from the state-of-the-art. As a result, fabricated FPA prototypes achieved tailorable experimental fluid flow rates from ∼100 to ∼3000 μL min−1 without the use of electricity. Moreover, a portable human-powered two-fluid pulsatile fluidic mixer, capable of generating fully-mixed fluids in 10 seconds, is presented, demonstrating the application of FPAs towards on-chip integration into more complex 3D printed fluidic networks

Female Sex Development and Reproductive Duct Formation Depend on Wnt4a in Zebrafish.

In laboratory strains of zebrafish, sex determination occurs in the absence of a typical sex chromosome and it is not known what regulates the proportion of animals that develop as males or females. Many sex determination and gonad differentiation genes that act downstream of a sex chromosome are well conserved among vertebrates, but studies that test their contribution to this process have mostly been limited to mammalian models. In mammals, WNT4 is a signaling ligand that is essential for ovary and Müllerian duct development, where it antagonizes the male-promoting FGF9 signal. Wnt4 is well conserved across all vertebrates, but it is not known if Wnt4 plays a role in sex determination and/or the differentiation of sex organs in nonmammalian vertebrates. This question is especially interesting in teleosts, such as zebrafish, because they lack an Fgf9 ortholog. Here we show that wnt4a is the ortholog of mammalian Wnt4, and that wnt4b was present in the last common ancestor of humans and zebrafish, but was lost in mammals. We show that wnt4a loss-of-function mutants develop predominantly as males and conclude that wnt4a activity promotes female sex determination and/or differentiation in zebrafish. Additionally, both male and female wnt4a mutants are sterile due to defects in reproductive duct development. Together these results strongly argue that Wnt4a is a conserved regulator of female sex determination and reproductive duct development in mammalian and nonmammalian vertebrates

Tractable MCMC for Private Learning with Pure and Gaussian Differential Privacy

Posterior sampling, i.e., exponential mechanism to sample from the posterior distribution, provides $\varepsilon$-pure differential privacy (DP) guarantees and does not suffer from potentially unbounded privacy breach introduced by $(\varepsilon,\delta)$-approximate DP. In practice, however, one needs to apply approximate sampling methods such as Markov chain Monte Carlo (MCMC), thus re-introducing the unappealing $\delta$-approximation error into the privacy guarantees. To bridge this gap, we propose the Approximate SAample Perturbation (abbr. ASAP) algorithm which perturbs an MCMC sample with noise proportional to its Wasserstein-infinity ($W_\infty$) distance from a reference distribution that satisfies pure DP or pure Gaussian DP (i.e., $\delta=0$). We then leverage a Metropolis-Hastings algorithm to generate the sample and prove that the algorithm converges in W$_\infty$ distance. We show that by combining our new techniques with a careful localization step, we obtain the first nearly linear-time algorithm that achieves the optimal rates in the DP-ERM problem with strongly convex and smooth losses

Dyslexic Adults Can Learn from Repeated Stimulus Presentation but Have Difficulties in Excluding External Noise

We examined whether the characteristic impairments of dyslexia are due to a deficit in excluding external noise or a deficit in taking advantage of repeated stimulus presentation. We compared non-impaired adults and adults with poor reading performance on a visual letter detection task that varied two aspects: the presence or absence of background visual noise, and a small or large stimulus set. There was no interaction between group and stimulus set size, indicating that the poor readers took advantage of repeated stimulus presentation as well as the non-impaired readers. The poor readers had higher thresholds than non-impaired readers in the presence of high external noise, but not in the absence of external noise. The results support the hypothesis that an external noise exclusion deficit, not a perceptual anchoring deficit, impairs reading for adults