Amyloid Precursor Protein and Proinflammatory Changes Are Regulated in Brain and Adipose Tissue in a Murine Model of High Fat Diet-Induced Obesity

Background: Middle age obesity is recognized as a risk factor for Alzheimer’s disease (AD) although a mechanistic linkage remains unclear. Based upon the fact that obese adipose tissue and AD brains are both areas of proinflammatory change, a possible common event is chronic inflammation. Since an autosomal dominant form of AD is associated with mutations in the gene coding for the ubiquitously expressed transmembrane protein, amyloid precursor protein (APP) and recent evidence demonstrates increased APP levels in adipose tissue during obesity it is feasible that APP serves some function in both disease conditions. Methodology/Principal Findings: To determine whether diet-induced obesity produced proinflammatory changes and altered APP expression in brain versus adipose tissue, 6 week old C57BL6/J mice were maintained on a control or high fat diet for 22 weeks. Protein levels and cell-specific APP expression along with markers of inflammation and immune cell activation were compared between hippocampus, abdominal subcutaneous fat and visceral pericardial fat. APP stimulation-dependent changes in macrophage and adipocyte culture phenotype were examined for comparison to the in vivo changes. Conclusions/Significance: Adipose tissue and brain from high fat diet fed animals demonstrated increased TNF-a and microglial and macrophage activation. Both brains and adipose tissue also had elevated APP levels localizing to neurons and macrophage/adipocytes, respectively. APP agonist antibody stimulation of macrophage cultures increased specific cytokin

Vertebrate-faunal diversity profile of Sisauli Wetland, Belbari, Morang

The research work on Sisauli Wetland area of Belbari Municipality, Morang was conducted from first week of April to last week of August, 2018. A total of 12 species of mammals, 19 species of Aves, 13 species of reptiles, 8 species of amphibian and 19 species of Pisces were documented from Sisauli Wetland area.</jats:p

Strain driven negative Poisson's ratio and extraordinary light-harvesting response of Penta-BCN monolayer

We report here, structural, dynamic, and mechanical stability in pentagonal boron carbon nitride (p-BCN) monolayer, a new member of direct bandgap two-dimensional (2D) semiconductor. The identified visible range bandgap with excellent mechanical strength allows it to be a promising candidate material in optoelectronics and nanomechanics. By employing density functional theory (DFT), we reveal a unique geometrical reconstruction with rigidity in B$-$N and C$-$N bond lengths with applied strain. These quasi-sp$^3$ hybridized short and strong covalent bonding and unique geometry support the monolayer to possess extraordinary mechanical response. Remarkably, the very rare, negative Poisson's ratio (NPR), with softening and hardening, mechanical anisotropy to isotropy is achieved with the application of a small value of strain. Similarly, the desired bandgap is manipulated by loading the biaxial strain. Most importantly, our predictions on p-BCN show excellent optical response such as good static dielectric constant and refractive index, strong optical absorption (up to 1.08$\times$10$^5$ ${cm}^{-1}$ in VR and 7.01$\times$10$^5$ ${cm}^{-1}$ in UV) with small energy loss and reflectance both appearing in visible and ultraviolet regions (UV). The desired optical response along with the blue and red shift is demonstrated by tailoring with tensile and compressive strain. Additionally, the predicted strong optical anisotropy provides it's application in polarized photodetection.</jats:p

Strain driven negative Poisson\u27s ratio and extraordinary light-harvesting response of Penta-BCN monolayer

We report here, structural, dynamic, and mechanical stability in pentagonal boron carbon nitride (p-BCN) monolayer, a new member of direct bandgap two-dimensional (2D) semiconductor. The identified visible range bandgap with excellent mechanical strength allows it to be a promising candidate material in optoelectronics and nanomechanics. By employing density functional theory (DFT), we reveal a unique geometrical reconstruction with rigidity in B$-$N and C$-$N bond lengths with applied strain. These quasi-sp$^3$ hybridized short and strong covalent bonding and unique geometry support the monolayer to possess extraordinary mechanical response. Remarkably, the very rare, negative Poisson\u27s ratio (NPR), with softening and hardening, mechanical anisotropy to isotropy is achieved with the application of a small value of strain. Similarly, the desired bandgap is manipulated by loading the biaxial strain. Most importantly, our predictions on p-BCN show excellent optical response such as good static dielectric constant and refractive index, strong optical absorption (up to 1.08$\times$10$^5$ ${cm}^{-1}$ in VR and 7.01$\times$10$^5$ ${cm}^{-1}$ in UV) with small energy loss and reflectance both appearing in visible and ultraviolet regions (UV). The desired optical response along with the blue and red shift is demonstrated by tailoring with tensile and compressive strain. Additionally, the predicted strong optical anisotropy provides it\u27s application in polarized photodetection

Strain dependent electronic and optical responses of penta-BCN monolayer

We report here, structural, dynamic, and mechanical stability in pentagonal boron carbon nitride (p-BCN) monolayer, a new member of direct bandgap two-dimensional (2D) semiconductor. The identified visible range bandgap with excellent mechanical strength allows it to be a promising candidate material in optoelectronics, nanomechanics, and optomechanical sensors. By employing density functional theory (DFT), we reveal a unique geometrical reconstruction with rigidity in B–N and C–N bond lengths with applied strain. These quasi-sp3 hybridized short and strong covalent bonding and unique geometry support the monolayer to possess extraordinary mechanical response. The desired bandgap is manipulated by loading the biaxial strain. Most importantly, our predictions on p-BCN show excellent optical response such as good static dielectric constant and refractive index, strong optical absorption (up to 1.08 x 105 cm-1 in VR and 7.01 x 10 cm-1 in UV) with small energy loss and reflectance both appearing in visible and ultraviolet regions (UV). The desired optical response along with the blue and red shift is demonstrated by tailoring with tensile and compressive strain. The predicted strong optical anisotropy provides it’s application in polarized photodetection.This article is published as Sharma, Shambhu Bhandari, Ramchandra Bhatta, Rajendra Adhikari, and Durga Paudyal. "Strain dependent electronic and optical responses of penta-BCN monolayer." Carbon Trends 7 (2022): 100162. DOI: 10.1016/j.cartre.2022.100162. Copyright 2022 The Authors. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0). Posted with permission. DOE Contract Number(s): AC02-07CH1135

Strain driven negative Poisson's ratio and extraordinary light-harvesting response of Penta-BCN monolayer

We report here, structural, dynamic, and mechanical stability in pentagonal boron carbon nitride (p-BCN) monolayer, a new member of direct bandgap two-dimensional (2D) semiconductor. The identified visible range bandgap with excellent mechanical strength allows it to be a promising candidate material in optoelectronics and nanomechanics. By employing density functional theory (DFT), we reveal a unique geometrical reconstruction with rigidity in B$-$N and C$-$N bond lengths with applied strain. These quasi-sp$^3$ hybridized short and strong covalent bonding and unique geometry support the monolayer to possess extraordinary mechanical response. Remarkably, the very rare, negative Poisson's ratio (NPR), with softening and hardening, mechanical anisotropy to isotropy is achieved with the application of a small value of strain. Similarly, the desired bandgap is manipulated by loading the biaxial strain. Most importantly, our predictions on p-BCN show excellent optical response such as good static dielectric constant and refractive index, strong optical absorption (up to 1.08$\times$10$^5$ ${cm}^{-1}$ in VR and 7.01$\times$10$^5$ ${cm}^{-1}$ in UV) with small energy loss and reflectance both appearing in visible and ultraviolet regions (UV). The desired optical response along with the blue and red shift is demonstrated by tailoring with tensile and compressive strain. Additionally, the predicted strong optical anisotropy provides it's application in polarized photodetection.</jats:p

Study of strain-induced structural, electronic, mechanical, and transport properties of one-dimensional monoatomic ultrathin gold nanowire: A DFT-NEGF approach

We conduct the first principle calculation based on Density Functional Theory (DFT) and Non-equilibrium Green Function (NEGF) approach using Generalized Gradient Approximation (GGA). We have investigated the structural, electronic, mechanical, and electronic transport properties of a one-dimensional monoatomic gold nanowire (AuNW). Plus, the influence of strain in geometrical and electronic properties also investigated. The nanowire is stable with sustainable cohesive energy of -1.52 eV. The chemical stability is due to the partly ionic and covalent bonding between the gold atoms. The electronic band shows the metallic behavior of nanowire with a conductivity of 1G0 . Furthermore, the structural and electronic properties of AuNW change significantly due to the external strain. The compressive strain decreases the bond length conversely, tensile strain increases the bond length from the equilibrium length. Similarly, the higher electronic energy states shift towards the Fermi level due to tensile strain. Furthermore, the mechanical strength of the NW is calculated by finding the tensile stiffness of the nanowire which found to be 30.31 eV/Å that is threefold less than carbyne. The transport property is studied by designing the electrode-device-electrode regime by eliminating the current quantization effect due to the contacts. We obtain the current-voltage (IV ) characteristics by varying the chemical potential in the electrode region. The current-voltage profile shows AuNW follows Ohomic current-voltage relation until current gets saturated. All these findings show that monoatomic AuNW is a potential candidate for electronic, nanomechanical, and transport applications