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1.
SAGE Open Med ; 12: 20503121231221445, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38249941

RESUMO

Objectives: Workplace safety is essential to occupational health practices among healthcare providers, especially for nurses vulnerable to work-related hazards such as needle stick and sharp injuries. In Yemen, the underestimation and absence of reporting system and lack of health supplies in a collapsed health system exacerbated the needle stick and sharp injuries. This study aimed to identify the prevalence and associated factors of needle stick and sharp injuries among nurses in Taiz, Yemen. Methods: A cross-sectional study was conducted on a sample of 151 nurses working in three public hospitals in Taiz City. A semi-structured questionnaire was designed and delivered to the participants. Results: The prevalence of needle stick and sharp injuries among nurses was very high (95.36%), and around half were injured more than five times. Female nurses and those in an emergency department were more likely to be subjected to needle stick and sharp injuries (p = 0.018 and 0.021, respectively). Needle stick was the most common cause of injury (62.77%), and the fingers were the most exposed injury site (79.17%). Non-reporting injuries were very high (73.61%), and only one-third (34.21%) of them proceeded in the process of management, and less than one-quarter (23.68%) had been vaccinated. Conclusion: The prevalence of needle stick and sharp injuries among nurses in Taiz was very high, and determined by gender and place of work. Post-injury reporting and precautions were poor, which may increase the prevalence of hospital-acquired infections among clients and healthcare providers.

2.
J Basic Microbiol ; 64(2): e2300529, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38066405

RESUMO

Global production of sugarcane bagasse (SB) by sugar industries exceeds more than 100 tons per annum. SB is rich in lignin and polysaccharide and hence can serve as a low-cost energy and carbon source for the growth of industrially important microorganism. However, various other applications of SB have also been investigated. In this study, SB was used as an adsorbent to remove an azo dye, malachite green. Subsequently, the dye-adsorbed SB was fermented by Trametes pubescens MB 89 for the production of laccase enzyme. The fungal pretreated SB was further utilized as a substrate for the simultaneous production of multiple plant cell wall degrading enzymes including, cellulase, xylanase, pectinase, and amylase by thermophilic bacterial strains. Results showed that 0.1% SB removed 97.04% malachite green at 30°C after 30 min from a solution containing 66 ppm of the dye. Fermentation of the dye-adsorbed SB by T. pubescens MB 89 yielded 667.203 IU mL-1 laccase. Moreover, Brevibacillus borstelensis UE10 produced 38.41 and 18.6 IU mL-1 ß-glucosidase and pectinase, respectively, by using fungal-pretreated SB. Cultivation of B. borstelensis UE27 in the medium containing the same substrate yielded 32.14 IU mL-1 of endoglucanase and 27.23 IU mL-1 of ß-glucosidase. Likewise, Neobacillus sedimentimangrovi UE25 could produce a mix of ß-glucosidase (37.24 IU mL-1 ), xylanase (18.65 IU mL-1 ) and endoglucanase (26.65 IU mL-1 ). Hence, this study led to the development of a method through which dye-containing textile effluent can be treated by SB along with the production of industrially important enzymes.


Assuntos
Celulase , Corantes de Rosanilina , Saccharum , Celulose/metabolismo , Celulase/metabolismo , Poligalacturonase , Saccharum/metabolismo , Lacase , Trametes/metabolismo , Fermentação , beta-Glucosidase/metabolismo
3.
Antibiotics (Basel) ; 12(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37887182

RESUMO

Antibiotic resistance in uropathogens has increased substantially and severely affected treatment of urinary tract infections (UTIs). Lately, some new formulations, including meropenem/vaborbactam (MEV), ceftazidime/avibactam (CZA), and ceftolozane/tazobactam (C/T) have been introduced to treat infections caused by drug-resistant pathogens. This study was designed to screen Enterobacteriales isolates from UTI patients and to assess their antimicrobial resistance pattern, particularly against the mentioned (new) antibiotics. Phenotypic screening of extended-spectrum ß-lactamase (ESBL) and carbapenem resistance was followed by inhibitor-based assays to detect K. pneumoniae carbapenemase (KPC), metallo-ß-lactamase (MBL), and class D oxacillinases (OXA). Among 289 Enterobacteriales, E. coli (66.4%) was the most predominant pathogen, followed by K. pneumoniae (13.8%) and P. mirabilis (8.3%). The isolates showed higher resistance to penicillins and cephalosporins (70-87%) than to non-ß-lactam antimicrobials (33.2-41.5%). NDM production was a common feature among carbapenem-resistant (CR) isolates, followed by KPC and OXA. ESBL producers were susceptible to the tested new antibiotics, but NDM-positive isolates appeared resistant to these combinations. KPC-producers showed resistance to only C/T. ESBLs and carbapenemase encoding genes were located on plasmids and most of the genes were successfully transferred to recipient cells. This study revealed that MEV and CZA had significant activity against ESBL and KPC producers.

4.
Glob Pediatr Health ; 10: 2333794X231203857, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37846399

RESUMO

Objective. This study aims to highlight the low birth weight (LBW) in Taiz City (Yemen), as LBW is one of the public health challenges experiencing a profound effect on newborns. Methods. This was a cross-sectional study since the interview and medical records were the sources of data to be analyzed by SPSS. Results. The findings of this study include; a high prevalence of LBW (39.11%), the maternal age was not associated with LBW (P = .68), and education level, economic status, residence place, and health status were not associated with LBW (P < .05). Although the pre-pregnancy BMI, during-pregnancy BMI, MUAC, and gestational age were significantly associated with LBW (P < .05), the only risk factor was gestational age (OR = 9.606, CI = 3.988-23.135, P = .00). Conclusion. LBW is highly prevalent in Taiz (Yemen), so providing good healthcare services is essential to manage LBW incidence.

5.
Chemosphere ; 338: 139619, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37487975

RESUMO

The electrochemical degradation of alizarin red dye was studied using bismuth oxyhalide attached to bismuth vanadate nanocomposite synthesized via a simple solvothermal method. The electrochemical degradation of alizarin red dye was treated at current densities of 3 and 5 mA cm-1 for 30 min under different supporting electrolyte mediums (NaCl and KCl). Also, the electrochemical degradation of BiOBr/BiVO4 electrode shows higher degradation percentages of 97 and 99 for NaCl and KCl electrolyte solutions, which are higher degradation percentages than pure BiVO4 electrode (88 and 91 for NaCl and KCl). Also, the BiOBr/BiVO4 electrode shows 100% COD reduction during the 30th min of alizarin red dye using both NaCl and KCl electrolyte solutions. This may indicate that the prepared BiOBr/BiVO4 electrode shows an efficient electrode material for the degradation of textile dyes.


Assuntos
Poluentes Ambientais , Águas Residuárias , Bismuto , Cloreto de Sódio , Eletrodos
6.
Chemosphere ; 335: 139158, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37290507

RESUMO

In this study, magnetite particles were successfully embedded in sodium carboxymethyl cellulose as beads using FeCl3 as the cross-linker in two step-method and it was used as a Fenton-like catalyst to degrade sulfamethoxazole in aqueous solution. The surface morphology and functional groups influence of the Na-CMC magnetic beads was studied using FTIR and SEM analysis. The nature of synthesized iron oxide particles was confirmed as magnetite using XRD diffraction. The structural arrangement of Fe3+ and iron oxide particles with CMC polymer was discussed. The influential factors for SMX degradation efficiency were investigated including the pH of the reaction medium (4.0), catalyst dosage (0.2 g L-1) and initial SMX concentration (30 mg L-1). The results showed that under optimal conditions 81.89% SMX degraded in 40 min using H2O2. The reduction in COD was estimated to be 81.2%. SMX degradation was initiated neither by the cleaving of C-S nor C-N followed by some chemical reactions. Complete mineralization of SMX was not achieved which could be due to an insufficient amount of Fe particles in CMC matrix that are responsible for the generation of *OH radicals. It was explored that degradation followed first order kinetics. Fabricated beads were successfully applied in a floating bed column in which the beads were allowed to float in sewage water spiked with SMX for 40 min. A total reduction of 79% of COD was achieved in treating sewage water. The beads could be used 2-3 times with significant reduction in catalytic activity. It was found that the degradation efficiency was attributed to a stable structure, textural property, active sites and *OH radicals.


Assuntos
Sulfametoxazol , Poluentes Químicos da Água , Sulfametoxazol/química , Peróxido de Hidrogênio/química , Óxido Ferroso-Férrico , Celulose , Esgotos , Água , Poluentes Químicos da Água/análise , Oxirredução
7.
Chemosphere ; 334: 139014, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37224979

RESUMO

A co-precipitation technique has been used to prepare Bismuth tungstate nanoparticles (Bi2WO6) for electrochemical capacitors and electrochemical sensing of Ascorbic acid (AA). Using a scanning rate of 10 mV s -1, the electrode was performed as the pseudocapacitance behavior and the specific capacitance to be up to 677 Fg -1 at 1 A/g. Bi2WO6 versus Glassy carbon electrode (GCE) was also used to study the behavior of the Bi2WO6 modified electrodes in detecting ascorbic acid. This electrochemical sensor shows excellent electrocatalytic performance when ascorbic acid is present, as determined by differential pulse voltammetry. In solution, ascorbic acid diffuses to an electrode surface and controls its surface properties. Based on the results from the investigation, the sensor showed a detection sensitivity of 0.26 mM/mA, and a limit of detection (LOD) of 77.85 mM. It is clear from these results that Bi2WO6 may find application as an electrode material for supercapacitors and glucose sensors.


Assuntos
Nanopartículas Metálicas , Tungstênio , Tungstênio/química , Bismuto , Eletrodos , Nanopartículas Metálicas/química , Ácido Ascórbico/química , Técnicas Eletroquímicas/métodos
8.
Chemosphere ; 330: 138637, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37030340

RESUMO

A two-dimensional nanoflake (Fe/Cu-TPA) was prepared through a simple ultrasonic-centrifuge method. Fe/Cu-TPA has prominent performance on the removal of Pb2+ with low consistences. More than 99% lead (II) (Pb2+) was removed. The adsorption equipoise was established within 60 min for 50 mg L-1 Pb2+. Fe/Cu-TPA shows excellent regenerability with 19.04% decline of Pb2+ adsorption competence in 5 cycles. There are two models for Fe/Cu-TPA adsorption of Pb2+, pseudo-second-order dynamic model and Langmuir isotherm model, with a utmost adsorption competence of 213.56 mg g-1. This work offers a new candidate material for the industrial-grade Pb2+ adsorbents with promising application prospect.


Assuntos
Cobre , Poluentes Químicos da Água , Esgotos , Chumbo , Adsorção , Cátions , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
9.
Int J Biol Macromol ; 235: 123903, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-36870634

RESUMO

Agro-industrial wastes and by-products are the natural and abundant resources of biomaterials to obtain various value-added items such as biopolymer films, bio-composites and enzymes. This study presents a way to fractionate and to convert an agro-industrial residue, sugarcane bagasse (SB), into useful materials with potential applications. Initially cellulose was extracted from SB which was then converted into methylcellulose. The synthesized methylcellulose was characterized by scanning electron microscopy and FTIR. Biopolymer film was prepared by using methylcellulose, polyvinyl alcohol (PVA), glutaraldehyde, starch and glycerol. The biopolymer was characterized to exhibit 16.30 MPa tensile strength, 0.05 g/m2 h of water vapor transmission rate, 366 % of water absorption to its original weight after 115 min of immersion, 59.08 % water solubility, 99.05 % moisture retention capability and 6.01 % of moisture absorption after 144 h. Furthermore, in vitro studies on absorption and dissolution of model drug by biopolymer showed 2.04 and 104.59 % of swelling ratio and equilibrium water content, respectively. Biocompatibility of the biopolymer was checked by using gelatin media and it was observed that swelling ratio was higher in initial 20 min of contact. The extracted hemicellulose and pectin from SB were fermented by a thermophilic bacterial strain, Neobacillus sedimentimangrovi UE25 that yielded 12.52 and 6.4 IU mL-1 of xylanase and pectinase, respectively. These industrially important enzymes further augmented the utility of SB in this study. Therefore, this study emphasizes the possibility for industrial application of SB to form various products.


Assuntos
Celulose , Saccharum , Celulose/química , Metilcelulose , Álcool de Polivinil/química , Saccharum/química
10.
Bioresour Technol ; 377: 128958, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36965584

RESUMO

This study focuses on using Casuarina equisetifolia biomass for pilot-scale glucose oxidase production from Aspergillus niger and its application in the removal of trace organic contaminants (TrOCs) from municipal wastewater through the bio-Fenton oxidation. The cost of glucose oxidase was 0.005 $/U, including the optimum production parameters, 10% biomass, 7% sucrose, 1% peptone, and 3% CaCO3 at 96 h with an enzyme activity of 670 U/mL. Optimized conditions for H2O2 were 1 M glucose, 100 U/mL glucose oxidase, and 120 mins of incubation, resulting in 544.3 mg/L H2O2. Thus, H2O2 produced under these conditions lead to bio-Fenton oxidation resulting in the removal of 36-92% of nine TrOCs in municipal wastewater at pH 7.0 in 360 mins. Therefore, this work establishes the cost-effective glucose oxidase-producing H2O2 as an attractive bioremediating agent to enhance the removal of TrOCs in wastewater at neutral pH.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Glucose Oxidase , Biomassa , Peróxido de Hidrogênio , Análise Custo-Benefício , Poluentes Químicos da Água/análise , Oxirredução , Eliminação de Resíduos Líquidos/métodos
11.
Environ Res ; 220: 115212, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36623680

RESUMO

Mechanically-robust nanocomposite membranes have been developed via crosslinking chemistry and electrospinning technique based on the rational selection of dispersed phase materials with high Young's modulus (i.e., graphene and multiwalled carbon nanotubes) and Cassie-Baxter design and used for oil and water separation. Proper selection of dispersed phase materials can enhance the stiffness of nanocomposite fiber membranes while their length has to be larger than their critical length. Chemical modification of the dispersed phase materials with fluorochemcials and their induced roughness were critical to achieve superhydrophobocity. Surface analytic tools including goniometer, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, atomic force microscopy (AFM) and scanning electron microscope (SEM) were applied to characterize the superhydrophobic nanocomposite membranes. An AFM-based nanoindentation technique was used to measure quantitativly the stiffness of the nanocomposite membranes for local region and whole composites, compared with the results by a tensile test technique. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques were used to confirm composition and formation of nanocomposite membranes. These membranes demonstrated excellent oil/water separation. This work has potential application in the field of water purification and remediation.


Assuntos
Nanocompostos , Nanotubos de Carbono , Nanotubos de Carbono/química , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Environ Res ; 216(Pt 2): 114423, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36228691

RESUMO

Polycarboxylate (PCE) is a high performance superplasticizer for modern concrete. With the high quality sand becoming precious, more and more low quality sands are used in concrete. However, low quality sands generally contain a relatively high content of montmorillonite (MMT), which could seriously reduce the efficiency of PCE. In order to develop PCE suitable for concrete with low quality sands, the absorption behavior on MMT of PCE with different side chains and acid/ether ratio was investigated. In order to explore the effect of MMT on PCE, two macromonomers were selected, isoprene glycol ether 400(TPEG400) and isoprene glycol ether 2400 (TPEG2400), to synthesize six long and short side chain comb-type PCEs with acid-ether ratios of 1.5:1, 2.5:1 and 3.5:1, respectively. The MMT tolerance mechanism of comb-type PCE in MMT-containing cement slurry was examined by FT-IR, DLS, TOC and other analysis. The PCE with long side chain is much easier to be inserted into the layered structure of MMT, resulting in intercalation absorption. The absorption amount of two kinds of side chain PCE on the MMT particles decreased as the acid ether ratio increases. PCE with long side chains showed shear-thickening properties in MMT-containing cement slurry, on the contrary, short side chains showed shear-thinning properties.

13.
Chemosphere ; 306: 135567, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35792211

RESUMO

Antibiotic contamination from animal production and wastewater treatment process will release antibiotic resistant genes to the environment and potentially threaten human health. Meanwhile, the residual antibiotic in manure could have inactive impacts on anaerobic digestion (AD). This study explores the effect of sulfamethazine on manure AD mediated by biochar. The results show that biochar weakens the adverse effects of sulfamethazine on AD by adsorption sulfamethazine during the initial stage (0-3 days) of AD and promoting the growth of hydrolytic bacteria (especially Firmicutes and Bacteroidetes) and methanogens (especially Methanothrix and Methanosarcina). Besides, the presence of biochar improves the biogas production capacity of AD and promotes microbial diversity and community richness. Thus, the addition of biochar greatly reduces sulfamethazine and is testified to be a desirable strategy to mitigate the inhibition of sulfamethazine on AD.


Assuntos
Esterco , Sulfametazina , Anaerobiose , Animais , Antibacterianos/farmacologia , Reatores Biológicos/microbiologia , Carvão Vegetal , Digestão , Humanos , Esterco/microbiologia , Metano , Sulfametazina/farmacologia
14.
Nanomicro Lett ; 14(1): 118, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35488958

RESUMO

With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel (CA) with highly enhanced thermal conductivity (TC) in vertical planes was successfully obtained by constructing a vertically aligned silicon carbide nanowires (SiC NWs)/boron nitride (BN) network via the ice template-assisted strategy. The unique network structure of SiC NWs connected to BN ensures that the TC of the composite in the vertical direction reaches 2.21 W m-1 K-1 at a low hybrid filler loading of 16.69 wt%, which was increased by 890% compared to pure epoxy (EP). In addition, relying on unique porous network structure of CA, EP-based composite also showed higher TC than other comparative samples in the horizontal direction. Meanwhile, the composite exhibits good electrically insulating with a volume electrical resistivity about 2.35 × 1011 Ω cm and displays excellent electromagnetic wave absorption performance with a minimum reflection loss of - 21.5 dB and a wide effective absorption bandwidth (< - 10 dB) from 8.8 to 11.6 GHz. Therefore, this work provides a new strategy for manufacturing polymer-based composites with excellent multifunctional performances in microelectronic packaging applications.

15.
Sensors (Basel) ; 22(3)2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35161656

RESUMO

This paper proposes a barrier function adaptive non-singular terminal sliding mode controller for a six-degrees-of-freedom (6DoF) quad-rotor in the existence of matched disturbances. For this reason, a linear sliding surface according to the tracking error dynamics is proposed for the convergence of tracking errors to origin. Afterward, a novel non-singular terminal sliding surface is suggested to guarantee the finite-time reachability of the linear sliding surface to origin. Moreover, for the rejection of the matched disturbances that enter into the quad-rotor system, an adaptive control law based on barrier function is recommended to approximate the matched disturbances at any moment. The barrier function-based control technique has two valuable properties. First, this function forces the error dynamics to converge on a region near the origin in a finite time. Secondly, it can remove the increase in the adaptive gain because of the matched disturbances. Lastly, simulation results are given to demonstrate the validation of this technique.

16.
Micromachines (Basel) ; 12(10)2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34683243

RESUMO

In this paper, a common and widely used micro-heat sink (H/S) was redesigned and simulated using computational fluid dynamics methods. This H/S has a large number of microchannels in which the walls are wavy (wavy microchannel heat sink: WMCHS). To improve cooling, two (Al2O3 and CuO) water-based nanofluids (NFs) were used as cooling fluids, and their performance was compared. For this purpose, studies were carried out at three Reynolds numbers (Re) of 500, 1000, and 1500 when the volume percent (φ) of the nanoparticles (NPs) was increased to 2%. The mixture two-phase (T-P) model was utilized to simulate the NFs. Results showed that using the designed WMCHS compared to the common H/S reduces the average and maximum temperatures (T-Max) up to 2 °C. Moreover, using the Al2O3 NF is more suitable in terms of WMCHS temperature uniformity as well as its thermal resistance compared to the CuO NF. Increasing the φ is desirable in terms of temperature, but it enhances the pumping power (PP). Besides, the Figure of Merit (FOM) was investigated, and it was found that the value is greater at a higher volume percentage.

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