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131.
The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. In this study, we developed a facile approach to produce porous carbon from the dehydration of sucrose and use it for the preparation of nanocomposites with cobalt oxide (Co3O4). The nanocomposites were studied by the powder X-ray diffraction and scanning electron microscopy techniques, and they exhibited the cubic phase of cobalt oxide and porous structure of carbon. The nanocomposites showed significant OER activity in alkaline media, and the current densities of 10 and 20 mA cm−2 could be obtained at 1.49 and 1.51 V versus reversible hydrogen electrode (RHE), respectively. The impedance study confirms favorable OER activity on the surface of the prepared nanocomposites. The nanocomposite is cost-effective and can be capitalized in various energy storage technologies.

The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy.  相似文献   
132.
Background: The cytokine profile in unstimulated whole saliva (UWS) of patients with prediabetes and chronic periodontitis (CP) remains uninvestigated. The aim of this study is to assess interleukin (IL)‐6 and matrix metalloproteinase (MMP)‐8 levels in UWS of patients with CP with and without prediabetes. Methods: Eighty‐eight males (aged 39 to 51 years) were divided into three groups: group 1: 28 patients with CP and prediabetes; group 2: 30 patients with CP and without prediabetes; and group 3: 30 controls. Fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels, periodontal parameters (plaque index, bleeding on probing, probing depth, attachment loss, and marginal bone loss), and number of missing teeth were recorded. UWS samples were collected, and UWS flow rate (UWSFR) was measured. IL‐6 and MMP‐8 were measured in UWS using enzyme‐linked immunosorbent assay. P values <0.05 were considered statistically significant. Results: Mean FBG and HbA1c levels were significantly higher in group 1 (119.3 ± 3.1 mg/dL and 6.1% ± 0.2%) than group 2 (80.1 ± 3.5 mg/dL and 4.8% ± 0.5%; P <0.001) and group 3 (75.3 ± 2.2 mg/dL and 4.3% ± 0.2%; P <0.05). UWSFR was significantly higher in groups 2 (0.53 ± 0.1 mL/minute; P <0.05) and 3 (0.51 ± 0.1 mL/minute; P <0.01) than group 1 (0.33 ± 0.05 mL/minute). Periodontal parameters were worse in group 1 (P <0.05) and group 2 (P <0.05) than group 3. There was no difference in periodontal parameters, numbers of missing teeth, or salivary IL‐6 and MMP‐8 levels between patients in groups 1 and 2. Conclusion: Salivary IL‐6 and MMP‐8 levels are elevated in patients with CP with and without prediabetes.  相似文献   
133.
Background: The effect of glycemic control on severity of periodontal inflammatory parameters in patients with prediabetes is unknown. The aim of the present study is to assess the effects of glycemic control on self‐perceived oral health, periodontal parameters, and marginal bone loss (MBL) in patients with prediabetes. Methods: A total of 303 individuals were included. Hemoglobin A1c (HbA1c) and fasting blood glucose levels (FBGLs) were recorded. Participants were divided into three groups: 1) group A: 75 patients with prediabetes (FBGLs = 100 to 125 mg/dL [HbA1c ≥5%]); 2) group B: 78 individuals previously considered prediabetic but having FBGLs <100 mg/dL (HbA1c <5%) resulting from dietary control; and 3) control group: 150 medically healthy individuals. Self‐perceived oral health, socioeconomic status, and education status were determined using a questionnaire. Plaque index (PI), bleeding on probing (BOP), probing depth (PD), and clinical attachment loss (AL) were recorded. Premolar and molar MBLs were measured on panoramic radiographs. Results: Periodontal parameters (PI, BOP, PD, and AL) (P <0.01) and MBL (P <0.01) were worse among individuals in group A than those in group B. Self‐perceived gingival bleeding (P <0.001), pain on chewing (P <0.001), dry mouth (P <0.001), and oral burning sensations (P <0.05) were worse among patients in group A than those in group B. There was no difference in periodontal parameters, MBL, and self‐perceived oral symptoms among patients with prediabetes in group B and healthy controls. Conclusions: Self‐perceived oral health, severity of periodontal parameters, and MBL are worse in patients with prediabetes than controls. Glycemic control significantly reduces the severity of these parameters as well as the state of prediabetes in affected individuals.  相似文献   
134.
In this study, noble ligands of (E)-N′-(benzo[d]dioxol-5-ylmethylene)-4-methyl-benzenesulfonohydrazide (BDMMBSH) were prepared via a simple condensation method using benzo-[d][1,3]-dioxole carbaldehyde, benzenesulfonylhydrazine (BSH), and 4-methyl-benzenesulphonylhydrazine (4-MBSH) in good yield, which were crystallized in acetone, EtOAc, and EtOH. The BDMMBSH derivatives were characterized using different spectroscopic techniques, such as 1H-NMR, 13C-NMR, FTIR, and UV-Vis spectroscopy, and their crystal structures were analyzed using the single crystal X-ray diffraction method (SCXRDM). Subsequently, the BDMMBSH compounds were used for the significant detection of the carcinogenic heavy metal ion, lead (Pb2+), via a reliable electrochemical approach. A sensitive and selective Pb2+ sensor was developed via the deposition of a thin layer of BDMMBSH on a GCE with the conducting polymer matrix Nafion (NF). The sensitivity, LOQ, and LOD of the proposed sensor towards Pb2+ were calculated from the calibration curves to be 2220.0 pA μM−1 cm−2, 320.0 mM, and 96.0 pM, respectively. The validation of the BDMMBSH/GCE/NF sensor probe was performed via the selective determination of Pb2+ in spiked natural samples with a satisfactory and rational outcome.

A sensitive cationic sensor was developed by BDMMBSH onto GCE with 5% Nafion using electrochemical method, which was validated with the selective determination of Pb2+ in spiked samples and found satisfactory results.  相似文献   
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Neurotoxicity Research - Monoclonal antibodies (MAbs) against neurotoxin of Clostridium tetani are considered as a novel source of immunoglobulins for passive immunotherapy of tetanus. Toxin...  相似文献   
138.
Boron nitride (BN) nanomaterials are rapidly being investigated for potential applications in biomedical sciences due to their exceptional physico-chemical characteristics. However, their safe use demands a thorough understanding of their possible environmental and toxicological effects. The cytotoxicity of boron nitride nanotubes (BNNTs) was explored to see if they could be used in living cell imaging. It was observed that the cytotoxicity of BNNTs is higher in cancer cells (65 and 80%) than in normal cell lines (40 and 60%) for 24 h and 48 h respectively. The influence of multiple experimental parameters such as pH, time, amount of catalyst, and initial dye concentration on percentage degradation efficiency was also examined for both catalyst and dye. The degradation effectiveness decreases (92 to 25%) as the original concentration of dye increases (5–50 ppm) due to a decrease in the availability of adsorption sites. Similarly, the degradation efficiency improves up to 90% as the concentration of catalyst increases (0.01–0.05 g) due to an increase in the adsorption sites. The influence of pH was also investigated, the highest degradation efficiency for MO dye was observed at pH 4. Our results show that lower concentrations of BNNTs can be employed in biomedical applications. Dye degradation properties of BNNTs suggest that it can be a potential candidate as a wastewater and air treatment material.

Photocatalytic degradation studies of methyl orange using BNNTs.  相似文献   
139.
The first-principles approach has been used while employing the Perdew–Burke–Ernzerhof exchange-correlation functional of generalized gradient approximation (PBE-GGA) along with the Hubbard parameter to study the structural, optoelectronic, mechanical and magnetic properties of titanium-based MAX materials Ti3AC2 (A = P, As, Cd) for the first time. As there is no band gap found between the valence and conduction bands in the considered materials, these compounds belong to the conductor family of materials. A mechanical analysis carried out at pressures of 0 GPa to 20 GPa and the calculated elastic constants Cij reveal the stability of these materials. Elastic parameters, i.e., Young''s, shear and bulk moduli, anisotropy factor and Poisson''s ratio, have been investigated in the framework of the Voigt–Reuss–Hill approximation. The calculated values of relative stiffness are found to be greater than ½ for Ti3PC2 and Ti3AsC2, which indicates that these compounds are closer to typical ceramics, which possess low damage tolerance and fracture toughness. Optical parameters, i.e., dielectric complex function, refractive index, extinction coefficient, absorption coefficient, loss function, conductivity and reflectivity, have also been investigated. These dynamically stable antiferromagnetic materials might have potential applications in advanced electronic and magnetic devices. Their high strength and significant hardness make these materials potential candidates as hard coatings.

The first-principles approach has used the Perdew–Burke–Ernzerhof exchange-correlation functional of generalized gradient approximation along with the Hubbard parameter to study various properties of titanium-based MAX materials Ti3AC2 (A = P, As, Cd).  相似文献   
140.
ProposeIn this study, we re-assessed the criteria defined by the radiological society of North America (RSNA) to determine novel radiological findings helping the physicians differentiating COVID-19 from pulmonary contusion.MethodsAll trauma patients with blunt chest wall trauma and subsequent pulmonary contusion, COVID-19-related signs and symptoms before the trauma were enrolled in this retrospective study from February to May 2020. Included patients (Group P) were then classified into two groups based on polymerase chain reaction tests (Group Pa for positive patients and Pb for negative ones). Moreover, 44 patients from the pre-pandemic period (Group PP) were enrolled. They were matched to Group P regarding age, sex, and trauma-related scores. Two radiologists blindly reviewed the CT images of all enrolled patients according to criteria defined by the RSNA criteria. The radiological findings were compared between Group P and Group PP; statistically significant ones were re-evaluated between Group Pa and Group Pb thereafter. Finally, the sensitivity and specificity of each significant findings were calculated. The Chi-square test was used to compare the radiological findings between Group P and Group PP.ResultsIn the Group PP, 73.7% of all ground-glass opacities (GGOs) and 80% of all multiple bilateral GGOs were detected (p < 0.001 and p = 0.25, respectively). Single bilateral GGOs were only seen among the Group PP. The Chi-square tests showed that the prevalence of diffused GGOs, multiple unilateral GGOs, multiple consolidations, and multiple bilateral consolidations were significantly higher in the Group P (p = 0.001, 0.01, 0.003, and 0.003, respectively). However, GGOs with irregular borders and single consolidations were more significant among the Group PP (p = 0.01 and 0.003, respectively). Of note, reticular distortions and subpleural spares were exclusively detected in the Group PP.ConclusionWe concluded that the criteria set by RSNA for the diagnosis of COVID-19 are not appropriate in trauma patients. The clinical signs and symptoms are not always useful either. The presence of multiple unilateral GGOs, diffused GGOs, and multiple bilateral consolidations favor COVID-19 with 88%, 97.62%, and 77.7% diagnostic accuracy.  相似文献   
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