Suppression of the alpha -> beta-nickel hydroxide transformation in concentrated alkali: Role of dissolved cations

The presence of dissolved cations such as Al and Zn in alkaline electrolyte (6 M KOH) suppresses the alpha --> beta-nickel hydroxide transformation. The uptake of Al (10 mol%) and Zn (30 mol%) exhibited by the active material likely stabilizes the alpha-phase. Dissolved Al is deleterious to the performance of the nickel hydroxide electrode, whereas, dissolved Zn enhances the specific discharge capacity of nickel hydroxide by approximately 25% showing that the mode of metal uptake is different in the two cases

Nickel hydroxide electrodeposition from nickel nitrate solutions: Mechanistic studies

Nickel hydroxide electrodeposition by cathodic reduction of nitrate ions follows an electrochemical (EC) reaction followed by an irreversible chemical reaction mechanism. On subsequent cycling, the electrodeposited nickel hydroxide undergoes a reversible redox reaction. The mechanistic behavior of the nickel hydroxide electrodeposition from nickel nitrate solutions is investigated

Layered double hydroxides of Ni with Cr and Mn as candidate electrode materials for alkaline secondary cells

The use of layered double hydroxides (LDH) of Ni with Cr and Mn as electrode materials for alkaline secondary cells was studied. The presence of Cr and Mn suppresses β-nickel hydroxide formation which indicates their strong influence on the precipitation behavior of Ni2+. It is found that the LDH of Ni with Cr and Mn are electrochemically active and deliver capacities of 500 (Ni-Cr), 400 (Ni-Mn, x = 0.2) and 430 (Ni-Mn, x = 0.1) mAhg-1 of Ni respectively

Modelling of Random Textured Tandem Silicon Solar Cells Characteristics: Decision Tree Approach

We report decision tree (DT) modeling of randomly textured tandem silicon solar cells characteristics. The photovoltaic modules of silicon-based solar cells are extremely popular due to their high efficiency and longer lifetime. Decision tree model is one of the most common data mining models can be used for predictive analytics. The reported investigation depicts optimum decision tree architecture achieved by tuning parameters such as Min split, Min bucket, Max depth and Complexity. DT model, thus derived is easy to understand and entails recursive partitioning approach implemented in the “rpart” package. Moreover the performance of the model is evaluated with reference Mean Square Error (MSE) estimate of error rate. The modeling of the random textured silicon solar cells reveals strong correlation of efficiency with “Fill factor” and “thickness of a-Si layer

Effect of lightweight supports on specific discharge capacity of β-nickel hydroxide

While the performance of βbc (bc: badly crystalline)-nickel hydroxide is relatively unaffected by the use of different lightweight supports, the specific discharge capacity of crystalline β-Ni(OH)2 doubles to approximately 355 mAh g–1 Ni (theoretical, 456 mAh g−1) when pasted to a fibre support compared with 170 mAh g–1 Ni when pasted to a nickel foam. Consequently, the fibre is a superior support as it is unaffected by the quality of the active material and extracts a consistently high performance irrespective of the degree of crystallinity, moisture content, morphology and composition of the active material. Electrochemical impedance measurements indicate that a lower charge-transfer resistance at low states-of-charge is responsible for the superior performance of fibre supported β-Ni(OH)2 electrodes

Electrochemically Impregnated Aluminum-Stabilized α-Nickel Hydroxide Electrodes

Nickel-positive electrodes obtained by electrochemical impregnation of aluminum-substituted α-nickel hydroxide are found to deliver a reversible discharge capacity of ca. 450 mAh/g. This is much higher than the capacity of β-nickel hydroxide electrodes 200 mAh/g: this work; 225 mAh/g: Dixit et al., J. Power Sources, 63, 167 (1996) prepared under identical conditions and pasted electrodes comprising cobalt-doped nickel hydroxide 345 mAh/g: Faure et al., J. Power Sources, 36, 497 (1991). These observations suggest that the theoretical target-capacity for high-performance nickel-positive electrodes must be revised from the currently accepted value of 289 mAh/g (1e exchange) to 491 mAh/g 1.7e exchange: Corrigan and Knight, J. Electrochem. Soc., 136, 613 (1989). © 1999 The Electrochemical Society. S1099-0062(98)08-044-4. All rights reserved

The amyloid precursor protein controls PIKfyve function

While the Amyloid Precursor Protein (APP) plays a central role in Alzheimer's disease, its cellular function still remains largely unclear. It was our goal to establish APP function which will provide insights into APP's implication in Alzheimer's disease. Using our recently developed proteo-liposome assay we established the interactome of APP's intracellular domain (known as AICD), thereby identifying novel APP interactors that provide mechanistic insights into APP function. By combining biochemical, cell biological and genetic approaches we validated the functional significance of one of these novel interactors. Here we show that APP binds the PIKfyve complex, an essential kinase for the synthesis of the endosomal phosphoinositide phosphatidylinositol-3,5-bisphosphate. This signalling lipid plays a crucial role in endosomal homeostasis and receptor sorting. Loss of PIKfyve function by mutation causes profound neurodegeneration in mammals. Using C. elegans genetics we demonstrate that APP functionally cooperates with PIKfyve in vivo. This regulation is required for maintaining endosomal and neuronal function. Our findings establish an unexpected role for APP in the regulation of endosomal phosphoinositide metabolism with dramatic consequences for endosomal biology and important implications for our understanding of Alzheimer's disease

Comparative proximity biotinylation implicates the small GTPase RAB18 in sterol mobilization and biosynthesis

Loss of functional RAB18 causes the autosomal recessive condition Warburg Micro syndrome. To better understand this disease, we used proximity biotinylation to generate an inventory of potential RAB18 effectors. A restricted set of 28 RAB18 interactions were dependent on the binary RAB3GAP1–RAB3GAP2 RAB18–guanine nucleotide exchange factor complex. Twelve of these 28 interactions are supported by prior reports, and we have directly validated novel interactions with SEC22A, TMCO4, and INPP5B. Consistent with a role for RAB18 in regulating membrane contact sites, interactors included groups of microtubule/membrane-remodeling proteins, membrane-tethering and docking proteins, and lipid-modifying/transporting proteins. Two of the putative interactors, EBP and OSBPL2/ORP2, have sterol substrates. EBP is a Δ8-Δ7 sterol isomerase, and ORP2 is a lipid transport protein. This prompted us to investigate a role for RAB18 in cholesterol biosynthesis. We found that the cholesterol precursor and EBP-product lathosterol accumulates in both RAB18-null HeLa cells and RAB3GAP1-null fibroblasts derived from an affected individual. Furthermore, de novo cholesterol biosynthesis is impaired in cells in which RAB18 is absent or dysregulated or in which ORP2 expression is disrupted. Our data demonstrate that guanine nucleotide exchange factor–dependent Rab interactions are highly amenable to interrogation by proximity biotinylation and may suggest that Micro syndrome is a cholesterol biosynthesis disorder

Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018

Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe