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Zeolite imidazolate framework-8 (ZIF-8), which is a special subgroup of metal–organic frameworks (MOFs), was synthesized and modified by ethylenediamine (ZIF-8-EDA) to prepare an efficient adsorbent for the high sorption of Cd2+ ions from solution. The synthesized and modified ZIF-8 (ZIF-8-EDA) were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, Brunauer–Emmett–Teller (BET), field emission scanning electron microscopy (FE-SEM) with energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM) analysis. The optimum conditions for dosage of adsorbent, initial ion concentration, pH, and contact time were 0.05 g/l, 50 mg/l, 6, and 60 min, respectively, for cadmium ion sorption from aqueous solutions with a removal efficiency of 89.7% for ZIF-8 and 93.5% for ZIF-8-EDA. Adsorption kinetics and equilibrium data were analyzed using the Langmuir and Freundlich equations. The Langmuir model fitted the equilibrium data better than the Freundlich model. According to the Langmuir equation, the maximum uptake for the cadmium ions was 294.11(mg/g). The calculated thermodynamic parameters (ΔG°, ΔH°, and ΔS°) indicated that the adsorption process was feasible, spontaneous, and endothermic at 20–50 °C. Based on the results, the amino functionalized ZIF-8 had improved adsorption performance due to the replacing of the starting linker with organic ligands that had effective functional groups, leading to chemical coordination due to the interaction of metal ions with the non-bonding pair of electrons on the N atoms of the amino functional group. The selectivity toward metal ion adsorption by ZIF-8-EDA was Cd2+ > Pb2+ > Ni2+‏. [ABSTRACT FROM AUTHOR]

We study the evolution of scalar and tensor cosmological perturbations in the framework of the Einstein–Cartan theory of gravity. The value of the gravitational slip parameter which is defined as the ratio of the two scalar potentials in the Newtonian gauge, can be used to determine whether or not the gravity is modified. We calculate the value of slip parameter in the Einstein–Cartan cosmology and show that it falls within the observed range. We also discuss the evolution of the cosmic gravitational waves as another measure of the modification of gravity. [ABSTRACT FROM AUTHOR]

In the field of medicine, it is axiomatic that the need of a precise gene-editing tool is critical to employ therapeutic approaches toward pathogenic mutations, occurring in human genome. Today we know that most of genetic defects are caused by single-base pair substitutions in genomic DNA. The ability to make practically any targeted substitutions of DNA sequences at specified regions in the human genome gives us the chance to employ gene therapy in most known diseases associated with genetic variants. In this regard, CRISPR/Cas9 applications is becoming more and more popular along with the significant advancements of life sciences, by employing this technology in genome-editing and high-throughput screenings. Several CRISPR/Cas-based mammalian cell gene-editing techniques have been developed during the last decade, including nucleases, base editors, and prime editors, all of which have the exact mechanism at first glance. However, they address a subset of known pathogenic sequence mutations using different methods. First, we highlight the development of CRISPR-based gene-editing tools. Then we describe their functions and summarize the conducted research studies, which are increasing the reliability of these strategies to better efficiencies for prospective gene therapies in the near future. Lastly, we compare the capabilities of all these platforms together besides their probable limitations. [ABSTRACT FROM AUTHOR]

Evidence has shown that cardiometabolic disorders (CMDs) are amongst the top contributors to COVID-19 infection morbidity and mortality. The reciprocal impact of COVID-19 infection and the most common CMDs, the risk factors for poor composite outcome among patients with one or several underlying diseases, the effect of common medical management on CMDs and their safety in the context of acute COVID-19 infection are reviewed. Later on, the changes brought by the COVID-19 pandemic quarantine on the general population's lifestyle (diet, exercise patterns) and metabolic health, acute cardiac complications of different COVID-19 vaccines and the effect of CMDs on the vaccine efficacy are discussed. Our review identified that the incidence of COVID-19 infection is higher among patients with underlying CMDs such as hypertension, diabetes, obesity and cardiovascular disease. Also, CMDs increase the risk of COVID-19 infection progression to severe disease phenotypes (e.g. hospital and/or ICU admission, use of mechanical ventilation). Lifestyle modification during COVID-19 era had a great impact on inducing and worsening of CMDs. Finally, the lower efficacy of COVID-19 vaccines was found in patients with metabolic disease. [ABSTRACT FROM AUTHOR]

A novel Zn (II) organic framework comprising 2-phenyl benzimidazole (ZPBIF-1) was synthesized by using a solvothermal method. The characterization of the synthesized MOF was performed utilizing XRD, SEM, FT-IR, 1H-NMR, 13C-NMR, MS, XPS, TG/DTA, and N2 sorption analysis. ZPBIF-1 was successfully utilized to remove Acid red 88, Basic Violet 14, Basic Blue 54, and Congo red dyes in aqueous solutions. In this study, some parameters, including adsorbent dosage, initial dye concentration, contact time, temperature, and pH, were examined. To evaluate the experimental data, Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich isotherm models were used. In this case, Langmuir is the most suitable model. Several kinetic models, including First-order, pseudo-first-order, second-order, and Pseudo-second-order kinetic models, Elovich's, and Weber's intraparticle diffusion models, were utilized to comprehend the detailed adsorption process. According to the pseudo-second-order kinetic model, dye sorption kinetics is best described. In addition, thermodynamic parameters like enthalpy (ΔH°), Gibbs free energy (ΔG°), and entropy (ΔS°) were also achieved and analyzed. The experimental studies thus suggest that Zn (II) metal–organic framework based on 2-phenyl benzimidazole could be a promising candidate for eliminating dyes from aqueous solution. Hence, the experimental studies suggest that a Zn (II) metal–organic framework based on 2-phenylbenzimidazole could be a promising candidate for eliminating dyes from aqueous solution. The maximum adsorption capacity of ZPBIF-1 was 1666.66, 1250, 1000, and 1250 mg/g for Acid red 88, Basic violet 14, Basic blue 54, and Congo red dyes, respectively. Furthermore, this method was used to remove contaminant dyes from textile wastewater, and an acceptable result was obtained. [ABSTRACT FROM AUTHOR]

Invasive candidiasis is an emerging fungal infection and a leading cause of morbidity in health care facilities. Despite advances in antifungal therapy, increased antifungal drug resistance in Candida albicans has enhanced patient fatality. The most common method for Candida albicans diagnosing is blood culture, which has low sensitivity. Therefore, there is an urgent need to establish a valid diagnostic method. Our study aimed to use the bioinformatics approach to design a diagnostic kit for detecting Candida albicans with high sensitivity and specificity. Eight antigenic proteins of Candida albicans (HYR1, HWP1, ECE1, ALS, EAP1, SAP1, BGL2, and MET6) were selected. Next, a construct containing different immunodominant B-cell epitopes was derived from the antigens and connected using a suitable linker. Different properties of the final construct, such as physicochemical properties, were evaluated. Moreover, the designed construct underwent 3D modeling, reverse translation, and codon optimization. The results confirmed that the designed construct could identify Candida albicans with high sensitivity and specificity in serum samples of patients with invasive candidiasis. However, experimental studies are needed for final confirmation. [ABSTRACT FROM AUTHOR]

Iron terephthalate metal-organic framework (MOF-235) was used as an additive in preparation and modification of perovskite layer of solar cells (PSCs). MOF-235 with the chemical formula [Fe3O(1,4-BDC)3(DMF)3][FeCl4](DMF)3] was used by the one-step solution method with the solvent engineering technique in perovskite precursor solution to synthesize the perovskite layer by solvothermal method. The perovskite layer film was characterized by XRD and FE-SEM analyzing methods to consider the effect of additive on stability and morphology of synthesized crystal layer after annealing processes. The results showed the incorporation of 5 wt% of MOF-235 increased the open-circuit voltage (Voc) of PCS from 0.99 ± 0.03 to 1.03 ± 0.02 V. Therefore, the power efficiency improved from 8.34 ± 0.37% to 9.56 ± 0.12%. As a result, the addition of MOF-235 improves the coverage of perovskite film on TiO2 layer that contributes to the stability of perovskite solar cells, due to the effects of rigidity and π–π bond of benzene ring in terephthalic acid. [ABSTRACT FROM AUTHOR]

Vascular occlusion is one of the major causes of mortality and morbidity. Blood vessel blockage can lead to thrombotic complications such as myocardial infarction, stroke, deep venous thrombosis, peripheral occlusive disease, and pulmonary embolism. Thrombolytic therapy currently aims to rectify this through the administration of recombinant tissue plasminogen activator. Research is underway to design an ideal thrombolytic drug with the lowest risk. Despite the potent clot lysis achievable using approved thrombolytic drugs such as alteplase, reteplase, streptokinase, tenecteplase, and some other fibrinolytic agents, there are some drawbacks, such as high production cost, systemic bleeding, intracranial hemorrhage, vessel re-occlusion by platelet-rich and retracted secondary clots, and non-fibrin specificity. In comparison, bacterial staphylokinase, is a new, small-size plasminogen activator, unlike bacterial streptokinase, it hinders the systemic degradation of fibrinogen and reduces the risk of severe hemorrhage. A fibrin-bound plasmin–staphylokinase complex shows high resistance to a2-antiplasmin-related inhibition. Staphylokinase has the potential to be considered as a promising thrombolytic agent with properties of cost-effective production and the least side effects. [ABSTRACT FROM AUTHOR]

In this study, Cu/Zn/Al2O3-AC (AC = activated carbon) catalyst was synthesized and evaluated for dimethoxymethane (DMM) reformation to hydrogen. The Cu/Zn/Al2O3-AC catalyst was prepared using high surface area metal organic frameworks (MOFs) consisting of Cu3(BTC)2 (MOF-199) and Zn4O(BDC)3 (MOF-5) for Cu(II) and Zn(II) sources respectively, as precursors while γ-Al2O3 was applied as support. The synthesized catalyst was investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), Temperature programmed desorption (NH3-TPD) and Energy-dispersive X-ray spectroscopy (EDX) techniques. Complete DMM conversion was observed over Cu/Zn/Al2O3-AC catalyst (Cu:Zn:Al mole ratio of 6:3:2) under atmospheric pressure, T = 533 K, GHSV = 20 NL h−1 gcat−1, N2/H2O/DMM = 24/5/1 volume percent (vol%) with hydrogen productivity of 12.8 L H2 h−1 gcat−1 and 64% hydrogen concentration. Application of MOFs as precursors and modified activated carbon as an acidic component provided the catalyst with the porous structure and high specific surface area for the hydrolysis of DMM, subsequently, high selectivity and productivity of hydrogen was obtained. [ABSTRACT FROM AUTHOR]

A one-pot procedure for the synthesis of novel planar aza-heterocycles possessing good fluorescence potencies was described. These benzo-imidazopyrimido[4,5-b]quinolone derivatives came from the reaction of 2-chloroquinoline-3-carboxaldehydes and 2-aminobenzimidazole using K2CO3 in DMF. The fluorescence study of these conjugated systems was also considered, which revealed that they have highly selective sensing of mercury. Consequently, to investigate another aspect of the reaction, a three-component reaction was developed by adding malononitrile to the aforementioned starting materials in the presence of l-proline under reflux condition in H2O/EtOH to provide amino-quinolin-3-yl-dihydrobenzo-imidazo-pyrimidine-3-carbonitriles in good yields. [ABSTRACT FROM AUTHOR]

In this study, an ionic complex of V(V) was synthesized by using ultrasonic method, and it was used as a precursor for production of a new catalyst for selective preparation of methylal or dimethoxymethane (DMM). By reaction between an ionic ligand [pyda.H][pydc] (LH), (pyda.H = 2,6-pyridine diammonium and pydc = 2,6-pyridinedicarboxylate) and ammonium vanadate, the five coordinated V(V) complex, [pyda.H][V(pydc)O], {2,6- diaminopyridinum 2,6-pyridinedicarboxylatodioxovanadate(V)}, VLH was synthesized. The prepared complex VLH was characterized by SEM, thermal analysis TGA/DTA, FT-IR spectroscopy and X-ray diffraction studies. The results showed that the yield of the reaction was increased up to 64%. The average particle sizes of the obtained complex VLH were about 50-60 nm. Also, the nano-catalyst of VO/AlO was synthesized by impregnation method and was prepared as a nano-catalyst with average particles sizes of 50-60 nm, and its characterization was performed by XRD, EDX and SEM methods. Finally, the prepared catalyst was used to converting of methanol to methylal at different process conditions. [ABSTRACT FROM AUTHOR]

In the present study nano-sized strontium-doped lanthanum manganite, LaSrMnO (LSM), were synthesized by three simple different methods (a) co-precipitation, (b) ultrasonic and (c) microwave-assisted co-precipitation. A lanthanum(III) coordination polymer, [pyda.H][La(pydc)(HO)]·2HO, where [pyda.H] = 2,6-diaminopyridinium, and (pydc) = 2,6-pyridinedicarboxylate, was used as a new precursor. The products were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), thermal gravimetric (TG) and differential thermal analyses (DTA), as well as by Energy-dispersive X-ray spectroscopy (EDX). The XRD results showed that the crystal lattice of the product obtained was orthorhombic perovskite structure. The porosity, particle size and homogeneity of calcinated LSM were strongly dependent on the preparation method. In addition, the results proved that the product formation time was decreased considerably when ultrasonic or microwave irradiation methods were used. [ABSTRACT FROM AUTHOR]

In the present research two different kinds of nickel oxide/gadolinium-doped ceria (NiO-GDC) ( I and II) nanocomposites were prepared by means of the sol-gel method. The Ni(II) complex ( NiLH ), [Ni(pydc)·2(pyda·H)·2HO], [pydc (2,6-Pyridinedicarboxylic acid), pyda (2,6-diaminopyridine)], and Ni(NO)·6HO have been used as precursors. Characterization of the products was carried out by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray powder diffraction, zeta potential, thermogravimetric analysis, and nitrogen adsorption-desorption Brunauer, Emmett, and Teller measurements. The X-ray powder diffraction results showed that the crystal lattice of compound ( I) was obtained as a cubic fluorite structure and was found to have an average crystalline size of 48-63 nm. The comparison of the zeta potential of compounds ( I) and ( II) has shown that compound ( I) can carry a more positive charge and is almost stable. The scanning electron microscope and Brunauer, Emmett, and Teller analysis of compound ( I) revealed large homogeneous agglomerated pores and surface area. The results show that if compound ( I) is used in solid oxide fuel cells, it could be a suitable material for the anode of solid oxide fuel cells. Graphical Abstract: [ABSTRACT FROM AUTHOR]

In this investigation, nanoparticles and single crystals of a Cu(I) supramolecular compound, [Cu(dmph)-µ-I] ( 1), [dmph = 2,9-dimethyl-1,10-phenanthroline (neocuproine)], have been synthesized by the reaction of copper(II) acetate, KI and neocuproine as ligand in methanol using sonochemical and heat-gradient methods, respectively. The nanostructure of 1 was characterized by scanning electron microscopy, X-ray powder diffraction, FT-IR spectroscopy and elemental analyses, and the structure of compound 1 was determined by single-crystal X-ray diffraction. The crystal structure of compound 1 has been found to be a binuclear coordination compound. The Cu atoms have slightly distorted tetrahedral geometry with two iodine and two nitrogen coordinated atoms which are trans configuration to each other. Pure phase CuO nanoparticles were simply obtained by calcination of nanosized compound 1 at 700 °C under air atmosphere. This study demonstrates that the supramolecular compounds may be suitable precursors for the simple one-pot preparation of nanoscale metal oxide materials with different and interesting morphologies. [ABSTRACT FROM AUTHOR]

In this study, synthesis and characterization of two polymorphs of a new nano-sized zirconium(IV) complex, [ZrO(dmph)I] ( 1), {dmph = 2,9-dimethyl-1,10-phenanthroline (neocuproine)}, have been investigated in two different solvents. The reaction between zirconyl nitrate pentahydrate and potassium iodide with dmph as a ligand under ultrasonic irradiation in methanol and mono-ethylene glycol (MEG) leads to the formation of the nano-sized Zr(IV) complex. Characterization of the Zr(IV) complex has been performed using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy and elemental analysis. The thermal stability of the compound 1 has been studied by thermal gravimetric and differential thermal analyses. Particle sizes of the compound 1 have been decreased after thermal treatments in an autoclave. Pure monoclinic (m) and tetragonal (t) zirconia (ZrO) nanoparticles were readily synthesized from thermal decomposition of the Zr(IV) complex as a new precursor in presence of methanol and MEG as solvents, respectively. Zirconium oxide was characterized by FT-IR, XRD, and SEM to depict the phase and morphology. The results showed that, pure zirconia was produced with particle size about 59 nm and crystal system was monoclinic when methanol was used as a solvent during complexation process. On the other hand, particle sizes of zirconia with tetragonal structure were significantly reduced to about 39 nm, when MEG was used as solvent. [ABSTRACT FROM AUTHOR]

A new nano-sized La(III) supramolecular compound, [pyda.H][La(pydc)(HO)]·2HO ( 1), where [pyda.H] = 2,6-diaminopyridinium, and [pydc] = 2,6-pyridinedicarboxylate, was synthesized by the sonochemical method and characterized by field emission scanning electron microscope (FESEM), X-ray powder diffraction (XRD) and elemental analyses. Lanthanum oxide nanoparticles were prepared by direct thermal decomposition of 1 nanostructures in a programmable furnace up to 800 °C in ambient atmosphere. The structural characterization was performed by powder XRD; and, morphological observations by FESEM revealed that the quasi-spherical LaO nanoparticles obtained are well crystallized and uniform in both morphology and particle size. The study demonstrates that supramolecular compounds may be suitable precursors for the simple one-pot preparation of nanoscale metal oxide materials with different morphologies. [ABSTRACT FROM AUTHOR]

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A new lead(II) coordination polymer, [PbBr(CHNO)] ( 1), where CHNO is (2,4-diamino-6-piperidine-1-yl) pyrimidine N-oxide (minoxidil) is synthesized and characterized. Polymer 1 is synthesized in methanol by sonochemical and hydrothermal methods from lead(II) acetate, KBr and the minoxidil ligand. The crystal structure of [PbBr(CHNO)] indicates a syndiotactic coordination polymer. The Pb(II) atom lies on a mirror plane; the mirror plane is perpendicular to the pyrimidine ring bisecting the piperidine ring. N-H···O intramolecular and C-H···Br, N-H···N strong intermolecular interactions were observed. Micro-rods of PbO and nano-plates of PbOHBr were prepared by thermal decomposition of the nano-structured [PbBr(CHNO)] as a precursor. Characterization of the products was carried out using X-ray crystallography, elemental analysis, FTIR spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and thermal analysis. The sonochemical method resulted in a significant reduction of reaction time, reaction temperature and particle sizes of the products. [ABSTRACT FROM AUTHOR]