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Lead-tin (Pb-Sn) mixed-halide perovskites show potential for single-junction and tandem solar cells due to their adjustable band gaps, flexible composition, and superior environmental stability compared to three-dimensional (3D) perovskites. However, they have lower power conversion efficiencies. Understanding band alignment and charge carrier dynamics is essential for enhancing photovoltaic performance. In this view, herein we have prepared thin films of mixed Pb-Sn-based two dimensional (2D) Ruddlesden-Popper (RP) perovskites BA 2 FA(Pb 1- x Sn x ) 2 I 7 using a solution-based method. XRD study revealed the formation of orthorhombic phases for pristine (BA 2 FAPb 2 I 7 ) and mixed Pb-Sn perovskite thin films. UV-vis analysis showed that different n = 2 and n = 3 phases are present in the pristine sample. In contrast, Pb-Sn-doped samples showed no signature of other phases with a prominent red-shift in the visible spectral region. Cyclic voltammetry showed peaks for electron transfers at the band edges. Additionally, electrochemical and optical band gap matching was observed, along with decreased peak intensity due to less reactant and altered electrolyte-perovskite interface stability. Density functional theory (DFT) calculations revealed that the reduced band gap is due to the alteration of electrostatic interactions and charge distribution within the lattice upon Sn substitution. Low-temperature PL analysis provided insights into charge carrier dynamics with Sn substitution and suggested the suppression of higher n phases and self-trapped excitons/carriers in mixed Pb-Sn quasi-2D RP perovskite thin films. This study sheds light on the electron transfer phenomena between TiO 2 and SnO 2 layers by estimating band offsets from valence band maximum (VBM) and conduction band minimum (CBM), which is crucial for future applications in fabricating stable and efficient 2D-Pb-Sn mixed perovskites for optoelectronic applications.

Heteroplasmic mtDNA mutations typically act in a recessive way and cause mitochondrial disease only if present above a certain threshold level. We have experimentally investigated to what extent the absolute levels of wild-type (WT) mtDNA influence disease manifestations by manipulating TFAM levels in mice with a heteroplasmic mtDNA mutation in the tRNA Ala gene. Increase of total mtDNA levels ameliorated pathology in multiple tissues, although the levels of heteroplasmy remained the same. A reduction in mtDNA levels worsened the phenotype in postmitotic tissues, such as heart, whereas there was an unexpected beneficial effect in rapidly proliferating tissues, such as colon, because of enhanced clonal expansion and selective elimination of mutated mtDNA. The absolute levels of WT mtDNA are thus an important determinant of the pathological manifestations, suggesting that pharmacological or gene therapy approaches to selectively increase mtDNA copy number provide a potential treatment strategy for human mtDNA mutation disease.

The constitution of Nepal provides appointing a council of ministers both at federal and provincial levels without defining portfolios. There is a political agreement that MOH will be retained at the federal level. This article draws evidences around the world to meet health needs of Nepalese, the role of provincial ministry of health and coordinating structure at district/local level. The constitution emphasises on health and pronounced in 46 articles which provides guidance for the creation of federalized governance levels at federal, provincial and local levels. Retaining ministry of health at federal level without creating devolved structure at province and local levels in health sector will create difficulty in translating the spirit of the constitution and may not be effective in addressing health issues nationally and meeting global achievements like SDGs. It is suggested to establish an elaborate health system accordingly in Nepal to ensure constitutional mandate of health as a basic human right.

This case report demonstrates the clinical utility and versatility of mini-implants in carrying out different types of tooth movement in a 14-year-old boy with a 'severe' Class II division 1 malocclusion. Mini-implants were placed for 'en masse' retraction and intrusion of maxillary anterior teeth and for lower molar protraction. More than 11 mm of maxillary incisor retraction was achieved together with 3 mm of intrusion. There was significant reduction in the dentoalveolar protrusion and retraction of the upper lip, which resulted in decreased mentalis strain and improved chin projection. Cephalometric superimposition and panoramic radiographs showed no anchorage loss and good occlusion at the end of treatment.

Aim: The value of polythene film ('cling wrap') to improve thermal control and reduce postnatal weight loss in preterm, very low-birthweight babies was investigated., Methods: Consecutively born babies with birthweights between 750 and 1500 g were stratified by birthweight (<1250 g, 1251-1500 g) and randomised either to the cling wrap (CW) or no cling wrap (NCW) group. The baby bassinette of the RW was covered with cling wrap up to the level of the neck in the CW group for the 1st 7 days. The primary outcome variables were the incidence of hypothermia (axillary temperature < or = 36 degrees C) after initial stabilisation during the first 7 days and cumulative weight loss (percentage of birthweight) at 48 hours of age., Results: Of 51 babies, 26 were randomised to the CW and 25 to the NCW group. None of the babies in the CW group developed hypothermia in the 1st 7 days but 36% in the NCW group (p = 0.001) did. Babies who were hypothermic on admission took less time to reach normal temperature in the CW group. Cumulative weight loss in the 1st 48 hours was 5.0 + 5.6% in the CW group and 8.6 + 7.0% in the NCW group (p = 0.06)., Conclusion: Use of CW might be a simple method of maintaining temperature in very low-birthweight babies in developing countries.

Healthy term babies undergo a physiological nadir in serum calcium levels by 24-48 hours of age. This nadir may be related to the delayed response of parathyroid and calcitonin hormones in a newborn. This nadir may drop to hypocalcemic levels in high-risk neonates including infants of diabetic mothers, preterm infants and infants with perinatal asphyxia. This early onset hypocalcemia which presents within 72 hours, requires treatment with calcium supplementation for at least 72 hours. In contrast late onset hypocalcemia usually presents after 7 days and requires long term therapy. Ionized calcium is crucial for many biochemical processes and total serum calcium is a poor substitute for the diagnosis of hypocalcemia.

Lactococcus lactis ssp. cremoris MG1363 contains two FNR homologues, FlpA and FlpB, encoded by the distal genes of two paralogous operons (orfX(A/B)-orfY(A/B)-flpA/B). An flpA flpB double mutant strain is hypersensitive to hydrogen peroxide and has a depleted intracellular Zn(II) pool. The phenotypes of the flp mutant strains suggest that FlpA and FlpB control the expression of high and low affinity ATP-dependent Zn(II) uptake systems, respectively. Plate tests revealed that expression from a orfX(B)::lac reporter was activated by Cd(II), consistent with other Zn(II)-regulated systems. The link between a failure to acquire Zn(II) and hypersensitivity to oxidative stress suggests that Zn(II) may be required to protect vulnerable protein thiols from oxidation.