A systematic review of neighbourhood economic context on child obesity and obesity-related behaviours

Childhood obesity is of great importance given a third of children in the USA are overweight or obese. Previous research has examined neighbourhood economic context in relation to children's obesity and obesity-rated behaviours. However, different definitions and measures of neighbourhood context make it difficult to compare findings and make definitive conclusions. This review is to synthesize studies assessing the associations between neighbourhood economic context and children's obesity or obesity-related behaviours. The review included 39 studies investigating the relationship between residential neighbourhood economic context and children's obesity, dietary habits or physical activity after controlling for family-level economic status. Studies reported mixed results in the relationship between neighbourhood economic indicators and child obesity outcomes. Of reviewed studies, 60% showed an inverse association between higher neighbourhood economic status and obesity, and 33% and 14% showed positive associations between higher neighbourhood economic status and healthy dietary habits or physical activity. Several studies suggested gender, age, race/ethnicity, individual-level economic status, rurality and social connectedness as moderators in the neighbourhood-obesity association. Findings suggest that, in order to move towards causal inferences and inform interventions, future research should examine neighbourhood impacts longitudinally and test theory-driven mediators and moderators to clarify the mechanisms by which neighbourhoods influence child obesity.

Long-term Follow-up of Complicated Crown Fracture With Fragment Reattachment: Two Case Reports

Two cases of complicated crown fracture of the maxillary incisors were restored using the fragment reattachment technique. Root canal treatment was performed, and the fractured fragment was bonded to the tooth structure using a dentin adhesive system and a flowable composite resin, followed by the insertion of a fiber post using dual-cured resin cement. Reattached fragments have shown reliable prognosis without inflammatory signs around bonded junctions after long-term follow-up.

Low-p_{T} e^{+}e^{-} Pair Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV and U+U Collisions at sqrt[s_{NN}]=193 GeV at STAR

We report first measurements of e^{+}e^{-} pair production in the mass region 0.4<M_{ee}<2.6  GeV/c^{2} at low transverse momentum (p_{T}<0.15  GeV/c) in noncentral Au+Au collisions at sqrt[s_{NN}]=200  GeV and U+U collisions at sqrt[s_{NN}]=193  GeV. Significant enhancement factors, expressed as ratios of data over known hadronic contributions, are observed in the 40%-80% centrality of these collisions. The excess yields peak distinctly at low p_{T} with a width (sqrt[⟨p_{T}^{2}⟩]) between 40 and 60  MeV/c. The absolute cross section of the excess depends weakly on centrality, while those from a theoretical model calculation incorporating an in-medium broadened ρ spectral function and radiation from a quark gluon plasma or hadronic cocktail contributions increase dramatically with an increasing number of participant nucleons. Model calculations of photon-photon interactions generated by the initial projectile and target nuclei describe the observed excess yields but fail to reproduce the p_{T}^{2} distributions.

A 2.2 NEF Neural-Recording Amplifier Using Discrete-Time Parametric Amplification

This paper proposes a 2.2 noise efficiency factor (NEF) instrumentation amplifier for neural recording applications. A parametric amplifier based on the MOS C-V characteristic is designed as a pre-amplifier stage, lowering the input referred noise of the following stages by 3.4×. Sampling noise is minimized by oversampling the input signal and switching power is reduced by adopting an 8-phase soft-charging technique.

Ga-Doped Pt-Ni Octahedral Nanoparticles as a Highly Active and Durable Electrocatalyst for Oxygen Reduction Reaction

Bimetallic PtNi nanoparticles have been considered as a promising electrocatalyst for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs) owing to their high catalytic activity. However, under typical fuel cell operating conditions, Ni atoms easily dissolve into the electrolyte, resulting in degradation of the catalyst and the membrane-electrode assembly (MEA). Here, we report gallium-doped PtNi octahedral nanoparticles on a carbon support (Ga-PtNi/C). The Ga-PtNi/C shows high ORR activity, marking an 11.7-fold improvement in the mass activity (1.24 A mg_Pt^-1) and a 17.3-fold improvement in the specific activity (2.53 mA cm^-2) compared to the commercial Pt/C (0.106 A mg_Pt^-1 and 0.146 mA cm^-2). Density functional theory calculations demonstrate that addition of Ga to octahedral PtNi can cause an increase in the oxygen intermediate binding energy, leading to the enhanced catalytic activity toward ORR. In a voltage-cycling test, the Ga-PtNi/C exhibits superior stability to PtNi/C and the commercial Pt/C, maintaining the initial Ni concentration and octahedral shape of the nanoparticles. Single cell using the Ga-PtNi/C exhibits higher initial performance and durability than those using the PtNi/C and the commercial Pt/C. The majority of the Ga-PtNi nanoparticles well maintain the octahedral shape without agglomeration after the single cell durability test (30,000 cycles). This work demonstrates that the octahedral Ga-PtNi/C can be utilized as a highly active and durable ORR catalyst in practical fuel cell applications.