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This study involved the synthesis and catalytic activity testing of new nanocomposite beads (CuO-Fe2O3/CA-CMC-Cs) prepared by facile and environmentally friendly approach. CuO-Fe2O3 was prepared and applied for the catalytic reduction of 4-nitrophenol (4-NP). The results showed that CuO-Fe2O3 demonstrate high catalytic activity toward the reduction of 4-NP to 4-aminophenol (4-AP). Further, CuO-Fe2O3 were well-dispersed in the polymeric matrix of CA-CMC-Cs to prepare CuO-Fe2O3/CA-CMC-Cs beads via crosslinker agent (AlCl3). CuO-Fe2O3/CA-CMC-Cs beads were also applied for the catalytic reduction of nitrophenol isomers (4-NP, 2-NP, and 2,6-DNP), organic dyes (methyl orange (MO), eosin yellow (EY)) and potassium hexacyanoferrate (K3[Fe(CN)6]). K3[Fe(CN)6] was found to be effectively reduced by the beads and was completed within 30 s. While the catalytic reduction of 4-NP, EY and MO were completed within 300, 240 and 180 s and the rate constants were discovered to be 1.16 × 10−2 s−1, 1.68 × 10−2 s−1 and 1.51 × 10−2 s−1, respectively. The CuO-Fe2O3/CA-CMC-Cs beads catalytic activity was enhanced utilizing 4-NP as a model molecule. The beads had good catalytic activity and may be reused up to three times before losing their effectiveness. Additionally, the ability of the CuO-Fe2O3/CA-CMC-Cs beads to reduce 4-NP and MO in real samples such as wastewater, orange juice and strawberry juice was investigated where the reduction percentage was 91.5 %–89.0 % in the real samples. The results demonstrated that the beads were more efficient for reduction of 4-NP and MO in milk, while, in juices required more time and had a lower reduction percentage.

Nickel oxide-zinc oxide (NiO-ZnO) nano-catalyst was embedded in a carbohydrate polymer (Alg/NiO-ZnO) was successfully synthesized and used for the (photo)catalytic conversion of deleterious contaminants such as organic dyes (Acridine Orange ‘ArO’, Methylene Blue ‘MB’, Methyl Orange ‘MO’) and 4-Nitrophenol ‘4-NP’ as well. Solar light helped photo-degradation and NaBH4-assisted reduction of organic dyes, as water pollutants, were studied using Alg/NiO-ZnO. Furthermore, utilizing Na alg/NiO-ZnO as a catalyst for the photocatalytic degradation was found to be more efficient for ArO, however catalytic reduction of MB was the best among all contaminants. Scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-Ray Diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques were used to identify the shape and structure of Alg/NiO-ZnO. To gather the data, an ultraviolet-visible (UV) spectrophotometer is employed. Data collection and processing, graph creation, and analysis were all accomplished with Origin 2018. In just 13 minutes, the reduction percentage of MB was determined to be 95.25%, while ArO underwent photocatalytic degradation up to 77.5% in 150 minutes. Several factors are used to optimize the catalytic property of Alg/NiO-ZnO in the reduction of organic dyes. Alg/NiO-ZnO thus provides a promising technique for the efficient oxidation and reduction of pollutants from industrial effluents.

In this study, an efficient nanocomposite based on calcium alginate-carboxymethyl cellulose/iron oxide-copper oxide (CA-CMC/Fe2O3-CuO) is developed in beads form and utilized as nanoadsorbent and nanocatalyst. Further, the beads were coated with chitosan, resulting in Cs@CA-CMC/Fe2O3-CuO beads. The prepared beads exhibited exceptional adsorption capabilities for selected heavy metal ions. Notably, the Cs@CA-CMC/Fe2O3-CuO beads displayed remarkable adsorption among the other beads toward the three selected metal ions. Ag(I) was highly adsorbed by Cs@CA-CMC/Fe2O3-CuO beads, and the adsorption capacity of beads was 4.91 mgg−1, while 4.5 mgg−1 and 3.0 mgg−1 for Co(II) and Ni(II), respectively. Beads’ ability to adsorb Ag(I) varied depending on several factors. It was observed that the adsorption capacity of Ag(I) ions increased as the interaction time and metal concentration rose. However, increasing the beads dose led to a decrease in the Ag(I) ion adsorption. Further, the waste beads after Ag(I) adsorption were treated with reducing agent to form beads supported Ag nanoparticles (Ag/Cs@CA-CMC/Fe2O3-CuO) and used as effective catalyst for reducing 4-nitrophenol in the presence of NaBH4 as a reducing agent. Ag/Cs@CA-CMC/Fe2O3-CuO achieved reduction up to 93% for 4-NP within 30 min. The designed nanocomposite beads displayed several desirable attributes, including eco-friendliness and robust catalytic performance, making them highly promising for useful reduction of 4-NP.

A new type of nickel doped titanium oxide (Ni-TiO2) coated natural cotton fibers (CF) and Ni-TiO2 wrapped sodium alginate (Alg) hydrogel was developed for the efficient reduction of different contaminants. Ni-TiO2 was prepared by low-temperature method and coated on CF using Alg as a binder and entrapped inside Alg hydrogel. Ni-TiO2 coated CF (Ni-TiO2/CF) and Ni-TiO2 wrapped Alg (Ni-TiO2/Alg) were utilized for catalytic elimination of wastewater pollutants. Ni-TiO2/CF and Ni-TiO2/Alg were initially tested as nanocatalysts for reduction of potassium ferricyanide, 4-nitrophenol, congo red, and methylene blue (MB), and exhibited superior catalytic performance toward MB reduction. Different parameters such as catalyst amount, MB concentration, reducing agent amount, and recyclability were optimized. Comparatively, Ni-TiO2/CF revealed the best catalytic performance for MB reduction having the highest reaction rate constant (2.1564 min−1). Ultimately, the catalyst preserved superior activity in recyclability evaluation, confirming that Ni-TiO2/CF is a good catalyst for the efficient removal of MB up to four cycles. Ni-TiO2/CF can more easily be recovered compared to Ni-TiO2/Alg by easily pulling out the fibers from reaction medium, which is the main advantage of Ni-TiO2/CF. Moreover, Ni-TiO2/CF and Ni-TiO2/Alg were examined in real samples, providing the effective reduction of MB. The developed nanocatalyst offers a cost- and time-effective material for environmental safety purpose.

Tick-borne Coxiella spp. are emerging in novel regions infecting different hosts, but information regarding their occurrence is limited. The purpose of this study was the molecular screening of Coxiella spp. in various ticks infesting goats, sheep, camels, cattle, wild mice, and domestic fowls (Gallus gallus domesticus) in various districts of Khyber Pakhtunkhwa, Pakistan. Morphologically identified tick species were confirmed by obtaining their cox1 sequences and were molecularly screened for Coxiella spp. by sequencing GroEL fragments. Almost 345 out of 678 (50.9%) hosts were infested by nine tick species. Regarding the age groups, the hosts having an age >3 years were highly infested (192/345, 55.6%), while gender-wise infestation was higher in female hosts (237/345, 68.7%). In collected ticks, the nymphs were outnumbered (613/1,119, 54.8%), followed by adult females (293/1,119, 26.2%) and males (213/1,119, 19.7%). A total of 227 ticks were processed for molecular identification and detection of Coxiella spp. The obtained cox1 sequences of nine tick species such as Hyalomma dromedarii, Hyalomma anatolicum, Haemaphysalis cornupunctata, Haemaphysalis bispinosa, Haemaphysalis danieli, Haemaphysalis montgomeryi, Rhipicephalus haemaphysaloides, Rhipicephalus microplus, and Argas persicus showed maximum identities between 99.6% and 100% with the same species and in the phylogenetic tree, clustered to the corresponding species. All the tick species except Ha. danieli and R. microplus were found positive for Coxiella spp. (40/227, 17.6%), including Coxiella burnetii (15/40, 6.7%), Coxiella endosymbionts (14/40, 6.3%), and different Coxiella spp. (11/40, 4.9%). By the BLAST results, the GroEL fragments of Coxiella spp. showed maximum identity to C. burnetii, Coxiella endosymbionts, and Coxiella sp., and phylogenetically clustered to the corresponding species. This is the first comprehensive report regarding the genetic characterization of Coxiella spp. in Pakistan's ticks infesting domestic and wild hosts. Proper surveillance and management measures should be undertaken to avoid health risks.

Every day, the risk of water pollution grows. According to the World Health Organization (WHO), approximately half of the population of poor countries suffers from health problems linked to chemically or microbially contaminating drinkable water. Here in the present study, powder of taro-rhizome was used for preparation of supported bimetallic catalyst (Ag-Cu/TP). Characterization techniques used for analysis were XRD, TEM, SEM, FTIR and EDS. The prepared catalyst was then used in the catalytic reduction of chemical pollutants, including 4-nitrophenol (4-NP), 2,4,6-trinitrophenol (TNP), 2-nitrophenol (2-NP), methyl orange (MO), Acid Red 27 or amaranth (AM), Congo red (CR), Rhodamine B (RhB) and methyl red (MR). Turnover frequency was calculated for nitrophenol reductions, which were 0.98 min−1 for 2-NP and 3.45 min−1 for 4-NP. The Ag-Cu/TP catalyst shows outstanding performance and 99.4% of 4-NP was reduced just in 5 min with pseudo-first order constant of 5.24 × 10−3s−1, while 97% reduction of 2-NP took 17 min with the pseudo-first order constant of 1.01 × 10−3s−1. The prepared Ag-Cu/TP catalyst was packed into a glass column and organic dyes containing water were filtered through it to test the cleaning effectiveness of water from dyes. Excellent dye reduction was achieved. The prepared column reactor works excellent in the remediation of dyes and reduces about 68.7% CR. In addition, stability and reusability study showed exceptional reusability up to 5 times with very small loss of activity and was stable for up to 10 days.

In this work, we designed versatile heterogeneous nanocatalysts based on palladium nanoparticles (PdNPs) decorated on metal oxides supports (i.e., PdNPs/γ-Al2O3, PdNPs/WO3 and PdNPs/Nb2O5) by step-wise controlled synthesis of novel monodispersed ∼2 nm PdNPs at room temperature and then impregnated over metal oxides. PdNPs supported catalysts were characterised by powder XRD, TEM, HRTEM, NH3-TPD, N2-BET, H2-TPR, and XPS techniques. PdNPs based catalysts studied in two different model reactions were presented i.e., biomass platform chemical intermediate γ-valerolactone (GVL) conversion into pentanoic acid (PA) studied in vapor phase hydrogenolysis and 4-Nitrophenol (4-NP) reduction to 4-Aminophenol (4-AP) in liquid phase using NaBH4 as reducing agent over 0.5 wt% Pd nanoparticles -based nanocatalysts. The relationship between the active sites and the catalytic performance was evaluated. The Under optimized reaction conditions, over 0.5 wt% PdNPs/γ-Al2O3 catalyst exhibited the highest PA yield of 100%, and over 0.5 wt% PdNPs/WO3, 0.5 wt% PdNPs/Nb2O5 exhibited PA yields of 98% and 96% respectively. Over PdNPs/γ-Al2O3, PdNPs/WO3, and PdNPs/Nb2O5, the reduction reaction rates in the 4-NP to 4-AP are 5.40 × 10−3 s−1, 2.55 × 10−3 s−1 and 2.30 × 10−3 s−1 respectively. The calculated thermodynamic parameters of the Ea values for 4-NP to 4-AP reaction were 25.30, 26.75, and 27.81 KJ/mol for the PdNPs/γ-Al2O3, PdNPs/WO3 and PdNPs/Nb2O5, respectively.

Energy conversion has become an important technology for meeting energy production and consumption in the modern era. Water splitting and solar cell technologies are projected to close the gap between demand and consumption. Therefore, XGaO3 (X = Ba and Cs) compounds having characteristics i.e., electrical, optical, mechanical, and structural are depicted by using a density functional theory (DFT) based CASTEP software with ultrasoft pseudo-potential plane-wave and Generalized Gradient Approximation and Perdew Burke Ernzerhof exchange correlation functional (GGA-PBE). According to the findings, all of these compounds have a cubic “pm3m” structure with space group 221. The CsGaO3 and BaGaO3 have direct and indirect band gaps, with respect to electronic band-structure recreations. Density of states like total density of states (TDOS) and partial density of states (PDOS) commend the extent of localization of electrons in numerous bands. The optical properties of these compounds are explored by adjusting dispersion curve/relation for theoretical dielectric function (DF) scale to the corresponding peaks. As a result, these materials could be used to consume light in the visible zone via photo catalysis. CsGaO3 in combination with BaGaO3 can produce effective results, so these compounds have a remarkable potential application for sensing and water splitting.

Abstract Clean energy is highly needed at this time when the energy requirements are rapidly increasing. The observed increasing energy requirement are largely due to continued industrialization and global population explosion. The current means of energy source is not sustainable because of several reasons, most importantly, environmental pollution and human health deterioration due to burning of fossil fuels. Therefore, this study develops a new catalyst for hydrogen and oxygen evolution by water splitting as a potential energy vector. The binary metal oxide catalyst CdFe2O4 was synthesized by the solventless solid-mechanical alloying method. The as-prepared catalyst was well characterized by several methods including field emission scanning electron microscopy (FESEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared red spectroscopy (FTIR), energy dispersive X-ray spectroscopy (XEDS). The as-prepared catalyst, CdFe2O4 was successfully applied for water electrolysis at a moderate overpotential (470 mV). Specifically, the onset potential for the oxygen and hydrogen evolution reactions (OER and HER) were 1.6 V/RHE and 0.2 V/RHE respectively (vs. the reversible hydrogen electrode). The electrode potential required to reach 10 mA/cm-2 for OER (in alkaline medium) and HER (in acidic medium) was 1.70 V/RHE (corresponding to overpotential η = 0.47 and − 0.30 V/RHE (η = − 0.30 V) respectively. Similarly, the developed OER and HER catalyst displayed high current and potential stability for a period of 12 h. This approach is seen as the right track of making water electrolysis for hydrogen energy feasible through provision of low-energy requirement for the electrolytic process. Therefore, CdFe2O4 is a potential water splitting catalyst for hydrogen evolution which is a clean fuel and an antidote for world dependence on fossil fuel for energy generation.

Herein, a newly developed non-noble metal water splitting catalyst based on NiCuCoS3 was reported. Water splitting catalysts are largely developed with noble-based transition metals to lower the energy requirement for the overall water splitting reactions. However, the high cost of precious metal-based catalyst necessitated ongoing search for cheap and efficient oxygen and hydrogen evolution reaction catalysts. NiCuCoS3 were prepared by solventless solid state method and was well characterized by several techniques including field emission scanning electron microscopy (FESEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared red spectroscopy (FTIR), energy dispersive X-ray spectroscopy (XEDS). The as-prepared NiCuCoS3 was applied for water splitting activities with satisfactory performance. The onset for the oxygen evolution reaction (OER) in 1 M KOH was noticed at the electrode potential E = 1.78 V/RHE (vs. the reversible hydrogen electrode corresponding to an overpotential η = 0.55 V, with a current density of 10 mA cm−2 obtained at E = 1.92 V/RHE (η = 0.69 V). Similarly, the hydrogen evolution reaction (HER) occurred at an onset of E = −0.58 V/RHE, with a current density of 10 mA/cm2 obtained at E = 0.60 V/RHE (with η equal to E vs. RHE for the HER). Likewise, OER and HER had Tafel slopes (130 mV/dec and −116 mV/dec respectively). The developed catalyst also showed high stability as established by linear sweep voltammetry, chronoamperometry and chronopotentiometry. This approach is seen as the right track of making water electrolysis for hydrogen energy feasible through provision of low-energy requirement for electrolytic process.

Pollution problem increases with the same face as the industrial development. One of the toxic ingredients of these industrial effluents is the organic dyes. Zinc oxide/Graphene oxide nanocomposite (ZnO-GNc) was synthesized in aqueous solution by mixing ultrasonically various compositions. The prepared ZnO-GNc nanocomposite was characterized by XRD, FTIR, FE-SEM, EDX and TEM. XRD of Graphene oxide (GO) showed their crystalline nature and the average size was 3.54, 18.98 and 15.47 nm for GO, ZnO, and ZnO-GNc respectively. An active toxic and stable dye, Methyl red (MR) was employed as the target pollutant to evaluate the photocatalytic activity of ZnO-GNc. The photocatalytic performance of ZnO-GNc nanocomposite was compared with that of zinc oxide (ZnO) and GO. The effect of some parameters, dye concentration, pH and temperature of dye solution were studied. The kinetic studies show that the process of MR photocatalytic discoloration by ZnO-GNc followed first-order reaction kinetics under different conditions with the rate constant of 2.2 × 10−2 s−1. The possible reasons for the high values of photocatalytic efficiency of the ZnO-GNc may be due to the improved charge passage and separation.

Here, we have designed an efficient multipurpose photocatalytic system based on iron-doped tin oxide (Fe-SnO2) which exhibited excellent catalytic activity toward dyes degradation and hydrogen production. The synthesized photocatalyst was characterized using different spectroscopic techniques. Fe-SnO2 was tested in degradation of different dyes i.e., congo red (CR), acridine orange (ArO) and methyl orange (MO) and among these dyes, Fe-SnO2 was more efficient and selective toward CR which was degraded more than 95% in 30 min. Further, the catalytic efficiency of Fe-SnO2 was also evaluated toward photocatalytic hydrogen generation from aqueous solutions of methanol, ethanol, propanol, potassium hydroxide and Na2S + Na2SO3, where Fe-SnO2 displayed high catalytic activity toward hydrogen generation from methanol solution under sunlight. Moreover, the catalytic activity of Fe-SnO2 toward CR degradation and hydrogen production was optimized by using different combinations of operating conditions and no major loss in activity was observed upon running the same photocatalyst sample in different batches.

Synthesis and Characterization of six novel N,N-dioctylsuccinamate based room temperature ionic liquids (RTILs) bearing imidazolium, pyridinium, ester imidazolium, and quaternary ammonium cations is reported. Extraction of Pb(II) and Co(II) by these RTILs has been investigated. Ionic liquids (ILs) synthesized were [C4mim][N88SA], [C8mim][N88SA], [C4Py][N88SA], [C8Py][N88SA], [α-mim-ester][N88SA] and [N2244][N88SA] termed as L1, L2, L3, L4, L5 and L6 respectively. Liquid-liquid extraction was performed and all the six systems showed excellent extractability results for both Pb(II) and Co(II). During the process of extraction several factors i.e., nature of cation, pH of the aqueous phase, equilibration time, and initial metal ion concentration were investigated. The extraction efficiency of above 98 % for all types of extractants was observed. The nature of cation its concentration, equilibration time, and pH of the aqueous phase significantly influenced the extraction efficiency. Maximum extraction was observed at pH values between 4 and 8 and optimum contact time was observed to be 40–45 min. Increasing the metal ion concentration decreased the extraction efficiency. The extraction efficiency of both metal ions decreased in the order [N88SA][C8mim] (L2) > [α-mim-Ester][N88SA] (L5) > [N88SA][C4mim] (L1). This is evident from the order of extraction behaviour that increasing the bulkiness of cation, results in stronger complexation, hence increasing extraction.

For the photocatalytic degradation of the organic dyes present in wastewater, the ternary composites of metal-oxides nanopowders of zinc-iron-calcium (Zn-Fe-Ca), zinc-iron-antimony (Zn-Fe-Sb), zinc-iron-titanium (Zn-Fe-Ti) and zinc-iron-cobalt (Zn-Fe-Co) were synthesized and characterized by different instruments. The average particle size of the Zn-Fe-Ca and Zn-Fe-Ti mixed-oxides nanopowders was 10 ± 5 nm and that of Zn-Fe-Sb nanopowder was 20 ± 10 nm. The flakes of Zn-Fe-Co nanopowder were 10 ± 5 nm thick and 100 nm to 300 nm long. All the mixed-oxides were utilized for photocatalytic degradation of acridine orange (AO) where Zn-Fe-Sb degraded the 98 % of acridine orange (AO), within 20 min, while the same level of degradation was attained by Zn-Fe-Ti and Zn-Fe-Ca mixed-oxides in 80 min and 90 min, respectively. The more efficient Zn-Fe-Sb photocatalyst was further utilized for the degradation of malachite green (MG), brilliant green (BG), methyl orange (MO) and congo red (CR). Zn-Fe-Sb was found to be fast and efficient photocatalyst for the degradation of AO and therefore, the effect of various parameters was studied in detail to optimize the reaction conditions. Moreover, the Zn-Fe-Sb mixed-oxides were used to photodegrade the AO dye in four different environmental water samples (sea, tap and sewage). Keeping in view the practical conditions, a tube-type and funnel-type filters were designed for dynamic purification process using Zn-Fe-Sb mixed-oxides as catalyst under sunlight. The synthesized nanomaterials have great potential to contribute in the wastewater treatment technologies.

This paper describes the eco-friendly microwave-assisted green synthesis of pure and manganese-doped zinc oxide nanocomposites using ethanolic solution of castor oil as a reductant and capping agent. Solutions of Zn2+ and Mn2+ ions were mixed in fixed ratios to obtain 0%, 1%, 2.5%, 5%, and 7% pure and Mn-doped ZnO nanomaterials. The obtained nanomaterials were characterized by powder XRD, FT-IR spectroscopy, scanning electron microscopy, and EDX analyses. Powder XRD furnished characteristic fragmentation patterns for the confirmation of the synthesized materials and was also used to estimate the size of the synthesized nanoparticles by Scherrer’s equation. Diffraction patterns were characteristic of wurtzite structure and of the size in the range of 6.5, 5.6, 5.2, 5.1, and 4.3 nm for pure and Mn-doped ZnO nanocomposites. UV-visible spectra displayed maximum absorbance at 340 nm, and manganese doping caused a red shift. FT-IR spectra confirmed that the formation of zinc oxide nanoparticles as Zn─O appeared at below 700 cm−1 as well as the presence of organic moieties of the castor oil acting as stabilizing agents. Scanning electron micrographs (SEM) revealed all the synthesized materials were spherical in shape with some aggregation and polydispersity, and in the Energy-dispersive X-ray spectroscopy (EDX), specific peaks with characteristic patterns were seen for Zn, O, and Mn. A TEM micrograph displayed the hexagonal wurtzite structure of nanoparticles with average size less than 50 nm. Photocatalytic degradation of methylene blue was checked in the presence of sunlight and in darkness. Interestingly, samples placed under the solar radiation exhibited significant results only with the catalyst; all the samples used without the catalyst showed negligible degradation effects, and even the samples placed in the dark containing catalysts also displayed a negative effect. A mechanism for this significant activity is also proposed. In vitro the antibacterial potential was studied against two pathogenic strains, i.e., Streptococcus aureus and Escherichia coli; interestingly activity kept on increasing with the increasing manganese content. Overall, all the samples presented comparable activity to ciprofloxacin.

A polymeric hybrid nanocomposite, namely polythiophene tin(IV)phosphate (PTh–SnP), was expediently synthesized by incorporating polythiophene (PTh) in tin phosphate (SnP) to enhance the conducting behavior and sorption of heavy metal ions by porous polymeric cation exchanger. Composite was characterized by Fourier Transform-Infra Red and Transmission Electron Microscopy. The dc electrical conductivity studies carried out on the composite, showed conductivity within the range of 4.0 × 10−2–1.0 × 10−3 S/cm−1; measured by a 4-in line-probe dc electrical conductivity measuring technique. Ion-exchange kinetics for few divalent metal ions was evaluated by particle diffusion-controlled ion-exchange phenomenon at four different temperatures. The particle diffusion mechanism is confirmed by the linear τ (dimensionless time parameter) vs t (time) plots. The exchange processes thus controlled by the diffusion within the exchanger particle for the systems studies herein. Some physical parameters like self-diffusion coefficient (D0), energy of activation (Ea) and entropy (ΔS°) have been evaluated under conditions favoring a particle diffusion-controlled mechanism. Keywords: Nanotetrapod, Hybrid, Electrically conducting, Diffusion coefficient, Ion-exchange, Kinetics

Background: The current coronavirus disease-19 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a global outbreak of a disease from a new coronavirus. Several databases have been published on this pandemic, but the research community still needs an easy way to get comprehensive information on COVID-19. Objectives: COVID-19 pandemic database (CO-19 PDB) aims to provide wonderful insights for COVID-19 researchers with the well-gathered of all the COVID-19 data to one platform, which is a global challenge for the research community these days. Methods: We gathered 59 updated databases since December-2019 until May 2021 and divided them into six categories: digital image database, genomic database, literature database, visualization tools database, chemical structure database, and social science database. These categories focus on taking number of functions from the images, information from gene sequences, updates from relevant papers, essays, reports, articles, and books, the data or information in the form of maps, graphs, and charts, information of bonds between atoms, and updates about events of the physical and social environment, respectively. Results: Users can search the information of interest in two ways including typing the name of the database in the search bar or by clicking the right category directly. Computer languages such as CSS, PHP, HTML, Java, etc. are utilized to construct CO-19 PDB. Conclusion: This article attempts to compile up-to-date appropriate COVID-19 datasets and resources that have not been compiled and given in such an accessible and user-friendly manner. As a result, the CO-19 PDB offers extensive open data sharing for both worldwide research communities and local people. Further, we have planned future development of new features, that will be awesome for future study.

Hydrogels are three-dimensional, cross-linked, and supramolecular networks that can absorb significant volumes of water. Hydrogels are one of the most promising biomaterials in the biological and biomedical fields, thanks to their hydrophilic properties, biocompatibility, and wide therapeutic potential. Owing to their nontoxic nature and safe use, they are widely accepted for various biomedical applications such as wound dressing, controlled drug delivery, bone regeneration, tissue engineering, biosensors, and artificial contact lenses. Herein, this review comprises different synthetic strategies for hydrogels and their chemical/physical characteristics, and various analytical, optical, and spectroscopic tools for their characterization are discussed. A range of synthetic approaches is also covered for the synthesis and design of hydrogels. It will also cover biomedical applications such as bone regeneration, tissue engineering, and drug delivery. This review addressed the fundamental, general, and applied features of hydrogels in order to facilitate undergraduates, graduates, biomedical students, and researchers in a variety of domains.

Recently, hydrogels have been investigated for the controlled release of bioactive molecules, such as for living cell encapsulation and matrices. Due to their remote controllability and quick response, hydrogels are widely used for various applications, including drug delivery. The rate and extent to which the drugs reach their targets are highly dependent on the carriers used in drug delivery systems; therefore the demand for biodegradable and intelligent carriers is progressively increasing. The biodegradable nature of hydrogel has created much interest for its use in drug delivery systems. The first part of this review focuses on emerging fabrication strategies of hydrogel, including physical and chemical cross-linking, as well as radiation cross-linking. The second part describes the applications of hydrogels in various fields, including drug delivery systems. In the end, an overview of the application of hydrogels prepared from several natural polymers in drug delivery is presented.

Abstract Different chitosan-titanium oxide (CS-TiO2-x, with x = TiO2 loadings of 1, 5, 10,15 and 20 wt%) nanocomposite fibers were prepared and kept separately in each salt solution of CuSO4, CoNO3, AgNO3 and NiSO4 to adsorb Cu2+, Co2+, Ag+, and Ni+ ions, respectively. The metal ions loaded onto CS-TiO2 fibers were reduced to their respective zero-valent metal nanoparticles (ZV-MNPs) like Cu0, Co0, Ag0 and Ni0 by treating with NaBH4. The CS-TiO2 fibers templated with various ZV-MNPs were characterized and investigated for their catalytic efficiency. Among all prepared ZV-MNPs, Cu0 nanoparticles templated on CS-TiO2-15 fibers exhibited high catalytic efficiency for the reduction of dyes (methyl orange (MO), congo red (CR), methylene blue (MB) and acridine orange (AO)) and nitrophenols (4-nitrohphenol (4-NP), 2-nitrophenol (2-NP), 3-nitrophenol (3-NP) and 2,6-dinitrophenol (2,6-DNP)). Besides the good catalytic activities of Cu/CS-TiO2-15 fibers, it could be easily recovered by simply pulling the fiber from the reaction medium.

Chemical sensing and electrical transport properties of neodymium coblate, NdCoO3, was investigated in this work. It was prepared by using co-precipitation method. Pure neodymium chloride and cobalt chloride were mixing in the presence of sodium hydroxide and the obtained co-precipitated powder was calcined at 850 and 1000 °C. The synthesized composites, as-grown (NdCoO3-I), calcined at 850 °C (NdCoO3-II), and calcined at 1000 °C (NdCoO3-III) were studied in details in terms of their morphological and structural properties. The X-ray analysis confirmed that the synthesized products are well crystalline possessing single phase orthorhombic crystal system of space group Pbnm (62). The crystallite size of NdCoO3-I, NdCoO3-II, and NdCoO3-III is 22, 111, and 338 nm, respectively which reflect that crystallite size is increasing with increase in firing temperature. The DC resistivity was measured as a function of temperature in the temperature range from room temperature up to 200 °C. All NdCoO3 are semiconductor in this range of temperature but showed different activation energy which strongly depends on the crystallite size of the products. The activation energy decreased with increase in crystallite size, 0.798, 0.414 and 0.371 eV for NdCoO3-I, NdCoO3-II, and NdCoO3-III, respectively. Thus resistivity increases with increase in crystallite size of NdCoO3. All NdCoO3 products were tested as chemical sensor for acetone by electrochemical approaches and showed excellent sensitivity. Among the NdCoO3 samples, NdCoO3-III showed the highest sensitivity (3.4722 μAcm−2 mM−1) compared to other compositions and gradually decreased to 3.2407 μAcm−2 mM−1 with decreasing the crystallite size of NdCoO3-II. It is also observed that the sensitivity drastically decreased to 0.76253 μAcm−2 mM−1 in the case of NdCoO3-I. It is introduced an efficient route for the detection of environmental unsafe chemicals by electrochemical approach for the safety of healthcare and environmental fields in broad scales.

In this work, an efficient nanocatalyst was developed based on nanoadsorbent beads. Herein, carboxymethyl cellulose–copper oxide-cobalt oxide nanocomposite beads (CMC/CuO-Co2O3) crosslinked by using AlCl3 were successfully prepared. The beads were then coated with chitosan (Cs), Cs@CMC/CuO-Co2O3. The prepared beads, CMC/CuO-Co2O3 and Cs@CMC/CuO-Co2O3, were utilized as adsorbents for heavy metal ions (Ni, Fe, Ag and Zn). By using CMC/CuO-Co2O3 and Cs@CMC/CuO-Co2O3, the distribution coefficients (Kd) for Ni, Fe, Ag and Zn were (41.166 and 6173.6 mLg−1), (136.3 and 1500 mLg−1), (20,739.1 and 1941.1 mLg−1) and (86.9 and 2333.3 mLg−1), respectively. Thus, Ni was highly adsorbed by Cs@CMC/CuO-Co2O3 beads. The metal ion adsorbed on the beads were converted into nanoparticles by treating with reducing agent (NaBH4) and named Ni/Cs@CMC/CuO-Co2O3. Further, the prepared nanoparticles-decorated beads (Ni/Cs@CMC/CuO-Co2O3) were utilized as nanocatalysts for the reduction of organic and inorganic pollutants (4-nitophenol, MO, EY dyes and potassium ferricyanide K3[Fe(CN)6]) in the presence of NaBH4. Among all catalysts, Ni/Cs@CMC/CuO-Co2O3 had the highest catalytic activity toward MO, EY and K3[Fe(CN)6], removing up to 98% in 2.0 min, 90 % in 6.0 min and 91% in 6.0 min, respectively. The reduction rate constants of MO, EY, 4-NP and K3[Fe(CN)6] were 1.06 × 10−1, 4.58 × 10−3, 4.26 × 10−3 and 5.1 × 10−3 s−1, respectively. Additionally, the catalytic activity of the Ni/Cs@CMC/CuO-Co2O3 beads was effectively optimized. The stability and recyclability of the beads were tested up to five times for the catalytic reduction of MO, EY and K3[Fe(CN)6]. It was confirmed that the designed nanocomposite beads are ecofriendly and efficient with high strength and stability as catalysts for the reduction of organic and inorganic pollutants.

The current study was aimed at developing BC-Cactus (BCC) composite hydrogels with impressive mechanical features for their potential applications in medical and environmental sectors. BCC composites hydrogels were developed through cactus gel coating on a never dried BC matrix. The FE-SEM micrographs confirmed the saturation of BC fibrils with cactus gel. Additionally, the presence of various functional groups and alteration in crystalline behavior was confirmed through FTIR and XRD analysis. Mechanical testing illustrated a three-times increase in the strain failure and an increase of 1.6 times in the tensile strength of BCC composite. Absorption capabilities of BCC were much higher than pure BC and it retained water for a longer period of time. Additionally, the rewetting and absorption potentials of composites were also higher than pure BC. The composite efficiently adsorbed Pb, Zn, Cu, and Co metals. Biocompatibility studies against human HaCat cell line indicated much better cell adhesion and proliferation of BCC compared to BC. These findings advocate that the BCC composite could find applications in medical, pharmaceutical and environmental fields.

Escherichia coli is an important foodborne zoonotic pathogen. A total of 285 strains of E. coli were isolated from the production and supply chain of pork in Hubei, China and characterized. Their phylogroups (A, B1, B2, and D) and virulence genes of public health importance become more and more diverse along the production and supply chain.

OBJECTIVE: To determine the frequency of new coronary artery disease (CAD) cases during the years 2015, 2016 and 2017 in patients presenting to a cardiology clinic and to look for its current trends in Khyber Pakhtunkhwa (KP), Pakistan. METHODS: This descriptive study was conducted in a private clinic of interventional cardiologist, based in Lady Reading Hospital, Peshawar, Pakistan from January to March 2018. We retrospectively analyzed the echocardiography data and review of clinical records from January 2015 to December 2017 and identified cases of incident CAD based on Regional Wall Motion Abnormalities on echo. SPSS V20.0 was used for analysis. We applied the unpaired t-test to look for an increasing trend in CAD between 2015-2016, 2016-2017 and 2015 through 2017. RESULTS: A total of 3865 patients of incident coronary artery disease were identified from January 2015 to December 2017. The number of incident CAD patients was 998 in 2015, 1362 in 2016 and 1505 in 2017. We applied the unpaired t-test on the number of post myocardial infarction patients for an increasing trend in 2015 vs 2016, 2016 vs 2017 and 2015 vs 2017 which showed a p-value of

Substances at nanoscale, commonly known as “nanomaterials,” have always grabbed the attention of researchers for hundreds of years. Among these different types of nanomaterials, magnetic nanomaterials have been the focus of considerable attention during the last two decades as evidenced by an unprecedented increase in the number of research papers focusing these materials. Iron oxide magnetic nanoparticles have occupied a vital position in imaging phenomena; as drug vehicles, controlled/sustained release phenomena and hyperthermia; atherosclerosis diagnosis; prostate cancer. In fact, these are wonderful “theranostic” agents with some under clinical trials for human use. In this review, we have attempted to highlight the advances taking place in the field of magnetic nanoparticles as theranostic agents. Extensive progress has been made in the two most important parameters, namely, control over the size and shape which decide the importance of iron oxide magnetic nanoparticles by developing suitable procedures like precipitation, co-precipitation, thermal decomposition, hydrothermal synthesis, microemulsion synthesis and plant mediated synthesis. After using a suitable synthetic route, workers encounter the most daunting task linked with the materials at nanoscale i.e., the protection against corrosion. Only properly protected iron oxide magnetic nanoparticles can be further connected to different functional systems to make building blocks for application in catalysis, biology and medicines. Finally, “theranostics” which is a combined application of imaging and drug delivery has been discussed. With all the potential uses, toxicity of the of iron oxide magnetic nanoparticles has been discussed.

Intramuscular fat is a real challenge for the experts of animal science to improve meat quality traits. Research on the mechanism of adipogenesis provides invaluable information for the improvement of meat quality traits. This study investigated the effect of bta-miR-149-5p and its underlying mechanism on lipid metabolism in bovine adipocytes. Bovine adipocytes were differentiated and transfected with bta-miR-149-5p mimics or its negative control (NC). A total of 115 DEGs including 72 upregulated and 43 downregulated genes were identified in bovine adipocytes. The unigenes and GO term biological processes were the most annotated unigene contributor parts at 80.08%, followed by cellular component at 13.4% and molecular function at 6.7%. The KEGG pathways regulated by the DEGs were PI3K-Akt signaling pathway, calcium signaling pathway, pathways in cancer, MAPK signaling pathway, lipid metabolism/metabolic pathway, PPAR signaling pathway, AMPK signaling pathway, TGF-beta signaling pathway, cAMP signaling pathway, cholesterol metabolism, Wnt signaling pathway, and FoxO signaling pathway. In addition to this, the most important reactome enrichment pathways were R−BTA−373813 receptor CXCR2 binding ligands CXCL1 to 7, R−BTA−373791 receptor CXCR1 binding CXCL6 and CXCL8 ligands, R−BTA−210991 basigin interactions, R−BTA−380108 chemokine receptors binding chemokines, R−BTA−445704 calcium binding caldesmon, and R−BTA−5669034 TNFs binding their physiological receptors. Furthermore, the expression trend of the DEGs in these pathways were also exploited. Moreover, the bta-miR-149-5p significantly (p < 0.01) downregulated the mRNA levels of adipogenic marker genes such as CCND2, KLF6, ACSL1, Cdk2, SCD, SIK2, and ZEB1 in bovine adipocytes. In conclusion, our results suggest that bta-miR-149-5p regulates lipid metabolism in bovine adipocytes. The results of this study provide a basis for studying the function and molecular mechanism of the bta-miR-149-5p in regulating bovine adipogenesis.

Abstract: New flavonoidal glucosides leufolins A (1) and B (2), have been isolated from the ethyl acetate soluble fraction of the whole plants of Leucas urticifolia. Their structures were elucidated on the basis of extensive analysis of nuclear magnetic resonance (1D and 2D NMR) spectral data. Both of these compounds exhiited significant inhibitory potential against the enzyme butyrylcholinesterase.

Au-Cu alloy nanoparticles were synthesized by a chemical reduction method. Five samples having different compositions of Au and Cu (Au-Cu 3 : 1, Au-Cu 2 : 1, Au-Cu 1 : 1, Au-Cu 1 : 2, and Au-Cu 1 : 3) were prepared. The newly synthesized nanoparticles were characterized by electronic absorption, fluorescence, and X-ray diffraction spectroscopy (XRD). These alloy nanoparticles were also analyzed by SEM and TEM. The particle size was determined by SEM and TEM and calculated by Debye Scherrer’s equation as well. The results revealed that the average diameter of nanoparticles gets lowered from 80 to 65 nm as the amount of Cu is increased in alloy nanoparticles. Some physical properties were found to change with change in molar composition of Au and Cu. Most of the properties showed optimum values for Au-Cu alloy nanoparticles of 1 : 3. Cu in Au-Cu alloy caused decrease in the intensity of the emission peak and acted as a quencher. The fluorescence data was utilized for the evaluation of number of binding sites, total number of atoms in alloy nanoparticle, binding constant, and free energy of binding while morphology was deduced from SEM and TEM.

This work presents the fabrication and investigation of thermoelectric cells based on composite of carbon nanotubes (CNT) and silicone adhesive. The composite contains CNT and silicon adhesive 1∶1 by weight. The current-voltage characteristics and dependences of voltage, current and Seebeck coefficient on the temperature gradient of cell were studied. It was observed that with increase in temperature gradient the open circuit voltage, short circuit current and the Seebeck coefficient of the cells increase. Approximately 7 times increase in temperature gradient increases the open circuit voltage and short circuit current up to 40 and 5 times, respectively. The simulation of experimental results is also carried out; the simulated results are well matched with experimental results.

Transition metal doped semiconductor nanostructure materials (Sb2O3 doped ZnO microflowers, MFs) are deposited onto tiny µ-chip (surface area, ∼0.02217 cm(2)) to fabricate a smart chemical sensor for toxic ethanol in phosphate buffer solution (0.1 M PBS). The fabricated chemi-sensor is also exhibited higher sensitivity, large-dynamic concentration ranges, long-term stability, and improved electrochemical performances towards ethanol. The calibration plot is linear (r(2) = 0.9989) over the large ethanol concentration ranges (0.17 mM to 0.85 M). The sensitivity and detection limit is ∼5.845 µAcm(-2)mM(-1) and ∼0.11±0.02 mM (signal-to-noise ratio, at a SNR of 3) respectively. Here, doped MFs are prepared by a wet-chemical process using reducing agents in alkaline medium, which characterized by UV/vis., FT-IR, Raman, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), and field-emission scanning electron microscopy (FE-SEM) etc. The fabricated ethanol chemical sensor using Sb2O3-ZnO MFs is simple, reliable, low-sample volume (

Composite nanoparticles were synthesized by eco-friendly hydrothermal process and characterized by different spectroscopic techniques. All the spectroscopic techniques suggested the synthesis of well crystalline optically active composite nanoparticles with average diameter of ∼ 30 nm. The synthesized nanoparticles were applied for the development of chemical sensor which was fabricated by coating the nanoparticles on silver electrode for the recognition of phthalimide using simple I-V technique. The developed sensor exhibited high sensitivity (1.7361 µA.mM(-1).cm(-2)), lower detection limit (8.0 µM) and long range of detection (77.0 µM to 0.38 M). Further the resistances of composite nanoparticles based sensor was found to be 2.7 MΩ which change from 2.7 to 1.7 with change in phthalimide concentration. The major advantages of the designed sensor over existing sensors are its simple technique, low cost, lower detection limit, high sensitivity and long range of detection. It can detect phthalimide even at trace level and sense over wide range of concentrations. Therefore the composite nanoparticals would be a better choice for the fabrication of phthalimide chemical sensor and would be time and cost substituted implement for environmental safety.

Here, we have synthesized Ag2O3-ZnO nanocones (NCs) by a wet-chemical route using reducing agents at low temperature. The structural, optical and morphological properties of Ag2O3-ZnO NCs were investigated by several conventional techniques such as powder XRD, XPS, FESEM, XEDS, FTIR and UV/vis. spectroscopy. The analytical parameters of prepared NCs were also calculated for a selective detection of divalent cobalt [Co(II)] prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The selectivity of NCs toward various metal ions, including Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ni(II), and Zn(II) was studied. Results of the selectivity study demonstrated that Ag2O3-ZnO NC phase was the most selective towards Co(II) ion. The uptake capacity for Co(II) ion was experimentally calculated to be ∼76.69 mgg-1. Moreover, adsorption isotherm data provided that the adsorption process was mainly monolayer on homogeneous adsorbent surfaces of Ag2O3-ZnO NCs. Kinetic study revealed that the adsorption of Co(II) on Ag2O3-ZnO NCs phase followed the pseudo-second-order kinetic model. In addition, thermodynamic results provided that the adsorption mechanism of Co(II) ions on Ag2O3-ZnO NCs was a spontaneous process and thermodynamically favorable. Finally, the proposed method was validated by applying it to real environmental water samples with reasonable results.

In this contribution, a significant catalyst based on spinel ZnMn2O4 composite nanoparticles has been developed for electro-catalysis of nitrophenol and photo-catalysis of brilliant cresyl blue. ZnMn2O4 composite (hetaerolite) nanoparticles were prepared by easy low temperature hydrothermal procedure and structurally characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) and UV-visible spectroscopy which illustrate that the prepared material is optical active and composed of well crystalline body-centered tetragonal nanoparticles with average size of ∼ 38 ± 10 nm. Hetaerolite nanoparticles were applied for the advancement of a nitrophenol sensor which exhibited high sensitivity (1.500 µAcm(-2) mM(-1)), stability, repeatability and lower limit of detection (20.0 µM) in short response time (10 sec). Moreover, hetaerolite nanoparticles executed high solar photo-catalytic degradation when applied to brilliant cresyl blue under visible light.

Objective: To determine validity of myocardial perfusion imaging for the detection of coronary artery disease. Methodology: This was a hospital based observational study, conducted in department of Cardiology, Postgraduate Medical Institute, Lady Reading Hospital, Peshawar, K.P.K, from May 2008 to Jun 2009. Myocardial perfusion imaging was performed for all patients and invasive coronary angiography was taken as gold standard for the detection of coronary artery disease. Results: Total number of patients was 50; their mean age was 53.8±9.7 years. Men were 35 (70%) and women were 15 (30%). Myocardial perfusion imaging was reported as normal in 5(10%) patients while 45 (90%) had abnormal results. Coronary angiography showed 44 patients (88%) had > 50% stenosis in at least one coronary artery. Compared with coronary angiography, the sensitivity, specificity, positive predictive value and negative predictive values of myocardial perfusion imaging for detection of CAD were 98%, 67%, 95%, and 80% respectively. The sensitivity for the detection of ischemia in LAD, RCA, and CIRC territories were 89.7%, 94.7% and 72.2% respectively. Conclusion: Myocardial perfusion imaging has a high sensitivity for identifying patients with coronary artery disease. KEY WORDS: Myocardial perfusion imaging, Coronary artery disease, Coronary angiography

Background: To determine validity of myocardial dobutamine stress echocardiography in detection of coronary artery disease. Methods: In this descriptive study fifty patients with stable angina, undergoing coronary angiography, with or without past history of myocardial infarction were included. Dobutamine stress echocardiography was performed . Then 250 mg of dobutamine was infused. When patient failed to achieve 85% of age predictive maximum heart rate and had no symptoms and signs of ischemia, atropine in a dose of 1mg was added after the last stage. End points for test termination included limiting symptoms, 85% age predicted heart rate, maximum dose of dobutamine, ST- segment depression of > 2mm on ECG, severe hypertension, or a drop in systolic B.P of > 40mmHg from the previous stage or any significant arrhythmia. Images were recorded on video tape at baseline, at minimum dose, at peak dose and at recovery period. . The location of segmental wall motion abnormality was correlated with the location of diseased coronary arteries. Left ventricular wall motion was assessed qualitatively and graded as normal, hypokinetic, akinetic or dyskinetic . For coronary angiography Judkin’s technique was used via right femoral artery approach. Results: Mean age was 53.8±9.7. Men were 70%. Dobutamine stress echo was interpreted as normal in 14%, wall motion abnormality was noted in 86%. Coronary angiography showed 88% had > 50% stenosis in at least one coronary artery. The overall sensitivity, specificity, positive predictive value and negative predictive values of dobutamine stress echo were 93%, 83%, 98%, and 63% respectively while for LAD, RCA, CIRC the sensitivities were 84.6%, 73.3%, 72.2% respectively. Conclusion: Dobutamine stress echocardiography has a high sensitivity for identifying patients with coronary artery disease

In the title compound, C13H12N4O6, the mean plane through the nitrobenzene forms a dihedral angle of 37.38 (15)° with the plane through the imidazole ring. The crystal packing is stabilized by weak intermolecular C—H...O and C—H...N interactions together with π–π stacking interactions between nitrobenzene rings [centroid–centroid distance = 3.788 (3) Å] and between imidazole rings [centroid–centroid distance = 3.590 (2) Å].