Ultralow thermal conductivity and thermally-deactivated electrical transport in a 1D silver array with alternating δ-bonds.

We report the synthesis of a (TMA)AgBr (TMA = tetramethylammonium) crystal, which comprises inorganic anionic chains of -(AgBr)- stabilized by columnar stacks of organic TMA cations with a periodic arrangement of shorter and longer Ag(i)⋯Ag(i) bonds, even though all the Ag(i) ions are chemically equivalent. The presence of two chemically non-equivalent bridging Br ions is attributed to the primary cause of such an unusual arrangement, as clearly visualized in the charge density plot of (TMA)AgBr extracted from the theoretical calculations based on density functional theory. Remarkably, we identified from the orbital-projected density of states the existence of alternate δ-like bonding involving d orbitals of 4d Ag(i), which was attributed to the cause for ultralow thermal conductivity and thermally-deactivated electrical transport in (TMA)AgBr.

A Retrospective Study of Covid-19 Patients: A Real-Life Experience in a Secondary Care Hospital, Jashore, Bangladesh.

Covid-19 was first detected on 8th March of 2020 in Bangladesh after the global pandemic being started. As a new virus and disease there are scarcity of data of SARS-CoV-2 and Covid-19 respectively in our country. Aim of this study is to assess the demographic characteristics, clinical profiles, underlying co-morbid conditions, treatment pattern and outcome of the SARS-CoV-2 positive patients in Jashore, Bangladesh.

Excitonic cuprophilic interactions in one-dimensional hybrid organic-inorganic crystals.

The everlasting pursuit of hybrid organic-inorganic lead-free semiconductors has directed the focus towards eco-friendly copper-based systems, perhaps because of the diversity in chemistry, controlling the structure-property relationship. In this work, we report single crystals of a Cu(i) halide-based perovskite-like organic-inorganic hybrid, (TMA)CuBr, (TMA = tetramethylammonium), consisting of unusual one-dimensional inorganic anionic chains of -(CuBr)-, electrostatically stabilized by organic cations, and the Cu(i)-Cu(i) distance of 2.775 Å indicates the possibility of cuprophilic interactions.

Endoscopic Transnasal Repair of Cerebrospinal Fluid Leakage: Experience in BSMMU.

Endoscopic transnasal repair of CSF rhinorrhoea is gaining popularity around the world because of its tremendous success rate but it depends on defect site, size, technique of repair, experiences of surgeon and also patient's profile. Aim of this study was to analysis of surgical outcome of endoscopic transnasal repair of CSF rhinorrhoea. A retrospective study carried out in the department of ENT and Head neck surgery at Bangabandhu Sheikh Mujib Medical University (BSMMU) from January 2018 to December 2019.

Ag Nanoparticles-Induced Metallic Conductivity in Thin Films of 2D Metal-Organic Framework Cu(HHTP).

Two-dimensional (2D) metal-organic frameworks (MOFs) are usually associated with higher electrical conductivity and charge carrier mobility when compared with 3D MOFs. However, attaining metallic conduction in such systems through synthetic or postsynthetic modifications is extremely challenging. Herein, we present the fabrication of thin films of a 2D MOF, Cu(HHTP) (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene), decorated with silver nanoparticles (AgNPs) exhibiting significant conductivity enhancement at room temperature.

Insulator-to-metal-like transition in thin films of a biological metal-organic framework.

Temperature-induced insulator-to-metal transitions (IMTs) where the electrical resistivity can be altered by over tens of orders of magnitude are most often accompanied by structural phase transition in the system. Here, we demonstrate an insulator-to-metal-like transition (IMLT) at 333 K in thin films of a biological metal-organic framework (bio-MOF) which was generated upon an extended coordination of the cystine (dimer of amino acid cysteine) ligand with cupric ion (spin-1/2 system) - without appreciable change in the structure. Bio-MOFs are crystalline porous solids and a subclass of conventional MOFs where physiological functionalities of bio-molecular ligands along with the structural diversity can primarily be utilized for various biomedical applications.

Dengue presenting as a case of acute pancreatitis-A rare case report.

Atypical presentations may be presented with the common symptoms in Dengue. We, hereby, present a case of Dengue who was admitted in our hospital with the complaints of fever, upper abdominal pain, and vomiting, literally diagnosed as a case of acute pancreatitis.

Charge-transfer interface of insulating metal-organic frameworks with metallic conduction.

Downsizing materials into hetero-structured thin film configurations is an important avenue to capture various interfacial phenomena. Metallic conduction at the interfaces of insulating transition metal oxides and organic molecules are notable examples, though, it remained elusive in the domain of coordination polymers including metal-organic frameworks (MOFs). MOFs are comprised of metal centers connected to organic linkers with an extended coordination geometry and potential void space.

Psychological Assessment of Health-Care Workers Working during COVID-19 Pandemic Condition in Bangladesh.

The study was aimed to assess the psychological aspects and relevant factors of the health-care workers (HCWs) working in COVID 19 pandemic condition in Bangladesh. This online cross-sectional survey was conducted from different tertiary, secondary and primary hospitals in Bangladesh. Eligible 638 HCWs who were directly involved in the caring of confirmed or suspected COVID-19 patients were recruited in this study.

Photo- and Electrocatalytic Reduction of CO over Metal-Organic Frameworks and Their Derived Oxides: A Correlation of the Reaction Mechanism with the Electronic Structure.

A Ce/Ti-based bimetallic 2-aminoterephthalate metal-organic framework (MOF) was synthesized and evaluated for photocatalytic reduction of CO in comparison with an isoreticular pristine monometallic Ce-terephthalate MOF. Owing to highly selective CO adsorption capability, optimized band gaps, higher flux of photogenerated electron-hole pairs, and a lower rate of recombination, this material exhibited better photocatalytic reduction of CO and lower hydrogen evolution compared to Ce-terephthalate. Thorough probing of the surface and electronic structure inferred that the reducibility of Ce to Ce was due to the introduction of an amine functional group into the linker, and low-lying Ti(3) orbitals in Ce/Ti-2-aminoterephthalate facilitated the photoreduction reaction.

Understanding and tuning of spinterface for chemisorbed Ni-dinuclear quinonoid on Co(001) substrate.

Planar magnetic molecules are of great research interest in the past few years because of their possible application in molecular spintronics. Microscopic understanding of the adsorption and magnetic exchange interaction of these molecules to the metallic/magnetic surfaces may pave the way in developing efficient molecular spin switching devices. Herein, using density functional theory + U calculations, we have studied the structural, electronic, and magnetic properties of a Ni-dinuclear molecule chemically adsorbed on a Co(001) substrate.

Hypovitaminosis D and Its Relationship with Diabetes Mellitus among the Postmenopausal Women in Jashore, Bangladesh.

Background And Objectives: Vitamin D has diversity of functions including diabetes mellitus by its anti-inflammatory and immuno-modulatory effects. With the scarcity of the regarding data in Bangladesh, the aim of this study was to assess the relationship between hypovitaminosis D and diabetes mellitus among the postmenopausal women.

Methods: An observational study conducted from 1 July to 31 December, 2018 in Jashore, Bangladesh that recruited 152 eligible apparently healthy natural postmenopausal women above 45 years without having any chronic diseases and drugs interfering vitamin D metabolism.

Acute pancreatitis in a COVID-19 patient: An unusual presentation.

Any atypical presentation of COVID-19 may be occurred as a part of its elevated coagulopathy or cytokine storm syndrome. So therefore, physicians should be aware and prepared to handle such atypical presentations and sequelae related to COVID-19.

Spin transport through metal-dichalcogenides layers: a study from first-principles calculations.

Spin transport through monolayer and trilayers of molybdenum dichalcogenides were studied considering Co as leads. Detailed investigations of the electronic structure of the Co/MoS interface and magnetic tri-junctions are carried out by using density functional theory calculations to understand transport behavior. The study revealed that new spin-polarized hybridized states appeared at the Fermi level due to the formation of Co/MoS interface that effectively acted as a spin filter and enhanced the spin injection efficiency of the systems.

'POLIDON' Approach-A Novel Solution for the ENT & Skull Base Surgeons in COVID-19 era.

Health care providers (HCP) of ENT and Skull base surgery are highly vulnerable and mostly infected by novel coronavirus as they have to examine and perform procedures directly in oral cavity, oropharynx, nose, nasopharynx, where coronavirus remains in plenty. ENT & Skull base surgeons need to do several aerosol generating procedures (AGP). Most of the endoscopic and microscopic ENT & skull base surgery are AGP; like-mastoid surgery, sinus surgery, surgery of pituitary, tympanomastoid paraganglioma, temporal bone malignancy, tracheostomy etc.

Theoretical Investigations of Electronic Structure and Magnetic and Optical Properties of Transition-Metal Dinuclear Molecules.

In this work, we have reported the electronic structure, spin state, and optical properties of a new class of transition-metal (TM) dinuclear molecules (TM = Cr, Mn, Fe, Co, and Ni). The stability of these molecules has been analyzed from the vibration spectra obtained by using density functional theory (DFT) calculations. The ground-state spin configuration of the tetra-coordinated TM atom in each molecule has been predicted from the relative total energy differences in different spin states of the molecule.

Phenanthroimidazole-based chromophores for organic light-emitting diodes: synthesis, photophysical, and theoretical study.

Organic light-emitting diodes (OLED) are gaining attention and making a significant contribution to the area of lighting and displays technology. The synthesis of new materials that can act as a host as well as emissive materials is crucial and efforts have been made in this direction in this research. Here, four star-shaped fluorophores, with a donor-acceptor (D-A) structure and with triphenylamine and phenanthroimidazole groups with different substitutions at the N position of the imidazole moiety, were designed and synthesized.

A Modified Technique in Submandubular Salivary Gland Excision: Preservation of Facial Artery.

Cutting and ligation of facial artery is the conventional practice for excision of submandibular gland. Facial artery is the main arterial supply to the lower face. Its preservation results in preservation of large proportion of vascularity to the lower face, preserves vascularity of platysma myocutaneous flap, allows repair of lower lip using Bernard's technique; facial artery is one of the most important recipient artery for microvascular free flap in modern reconstructive surgery in head and neck oncology.

Structure-Sensitive Electrocatalytic Reduction of CO to Methanol over Carbon-Supported Intermetallic PtZn Nano-Alloys.

The electrochemical reduction of CO (CORR) to produce valuable synthetic fuel like CHOH not only mitigates the accumulated greenhouse gas from the environment but is also a promising direction toward attenuating our continuous reliance on fossil fuels. However, CORR to yield CHOH suffers because of large overpotential, competitive H evolution reaction (HER), and poor product selectivity. In this regard, intermetallic alloy catalysts open up a wide possibility of fine-tuning the electronic property and attain appropriate structures that facilitate selective CORR.

Enhanced photocatalytic efficiency of layered CdS/CdSe heterostructures: Insights from first principles electronic structure calculations.

Metal sulfides are emerging as an important class of materials for photocatalytic applications, because of their high photo responsive nature in the wide visible light range. In this class of materials, CdS with a direct band gap of 2.4 eV, has gained special attention due to the relative position of its conduction band minimum, which is very close to the energies of the reduced protons.

Ferromagnetism from non-magnetic ions: Ag-doped ZnO.

To develop suitable ferromagnetic oxides with Curie temperature (T) at or above room temperature for spintronic applications, a great deal of research in doping ZnO with magnetic ions is being carried out over last decade. As the experimental results on magnetic ions doped ZnO are highly confused and controversial, we have investigated ferromagnetism in non-magnetic ion, Ag, doped ZnO. When Ag replaces Zn in ZnO, it adopts 4d configuration for Ag which has single unpaired spin and suitable exchange interaction among these spins gives rise to ferromagnetism in ZnO with above room temperature T.