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Pure and copper-doped zinc oxide (ZnO) nanofibers (NFs) were fabricated by the sol-gel electrospinning (ES) technique with varying concentrations (1, 3, and 5 w%). Scanning electron microscope (SEM), X-ray diffraction (XRD), and ultraviolet-visible (UV-Vis) spectroscopy were used to investigate the morphology, structure, and optical properties of the NFs. The average fiber diameter (AFD) of the Cu-doped ZnO (Cu-Z) NFs decreased with the increase in doping concentration. The structural analysis found that all the NFs samples were polycrystalline and oriented along the (101) plane. Also, the crystalline size decreased from 26.58 to 18.45 nm as the copper (Cu) concentration increased, and a maximum crystalline size was observed for 5 w% Cu-Z NFs. The band gap of undoped and Cu-Z NFs was calculated from UV VIS spectra, and it was observed that the bandgap decreased from 3.45 to 2.9 eV due to the addition of 5 w% Cu. The sensing performance of the NFs was investigated for 50 ppm of ethanol vapor at various operating temperatures (25–300 °C). The results indicated that the 5 w% Cu-Z NFs had the highest response to ethanol vapor, of 12.65 for 50 ppm, with response and recovery times of 70s and 35s. The Cu-Z NFs exhibited good selectivity and stability while tested with other vapors.

AbstractThe flexible electromagnetic wave shielding material research is one of the attractive research topics. The literature reveals that thermoplastics, elastomers and natural and synthetic fabrics are modified using conductive and magnetic fillers for shielding applications. In the present work, Poly (ethylene terephthalate) plain weaved fabric (PETF) and PET fiber mats (PETM) are coated with copper (Cu), copper-Nickel (Cu-Ni) and designated as Cu-PETF, Cu-Ni-PETF and Cu-Ni-PETM. Further, all three samples were investigated, and Cu-Ni-PETF showed better electromagnetic shielding effectiveness and absorption dominating. Hence, it is recommended to use Cu-Ni coated PETF for lightweight polymer composites as reinforcements suitable for electromagnetic shielding encloses applications.

The atmosphere at many colleges and universities in the United States presents unique challenges for Black faculty including racism. It is well established that Black faculty, especially those at predominantly White institutions (PWIs), work in potentially hostile, unfriendly, and negative environments. Other concerns for Black faculty at PWIs include lack of mentors and tenure politics. Examples of tenure politics include a lack of guidance regarding the tenure and promotion process, a sense of isolation and lack of collegiality, and the inability to speak out on unfair treatment for fear of retribution during the tenure and promotion process. Black faculty often choose self-isolation, conformity, and silence as coping strategies. However, these strategies rarely address the associated psychological and social stress. Faculty learning communities (FLCs) have been touted as a better alternative. FLCs bind faculty together thereby providing a much-needed support for Black faculty struggling to survive in a predominantly White environment. This article is premised on the experiences of six Black FLC participants at one PWI. We recommend that PWIs should actively support the attempt(s) by Black faculty to create safe spaces such as an FLC, which can foster a sense of belonging and build their confidence. An additional recommendation is that PWIs should employ the services of a chief diversity officer to help create and maintain programs that enhance Black faculty experiences and make them more successful.

Background. The timing of screening for SARS-CoV-2 preoperatively by RT-PCR/CBNAAT, isolation protocols in preoperative wards, operation theatres, and postoperative wards are not well established. Methods. Evaluating the effectiveness of maintaining three pathways of two COVID-19 negative pathways (1) immediate testing pathway (2) isolation, or quarantine for five days and testing prior to surgery pathway, and (3) the tested COVID-19-positive pathway, was the aim of the study. The primary objective was to assess the utility and outcome of the two COVID-19 negative pathways adopted before surgery in terms of infectivity (seroconversion; COVID-19 positivity rate before surgery and symptomatic COVID-19 disease after surgery). The secondary objective was to derive a practical protocol for isolation or quarantine for emergency and elective surgery. Enrolled patients were grouped based on the need for surgery; Group-1 emergency basis, Group-2 urgent basis, and Group-3 COVID-19 positive and the three channels were kept separate with separate dedicated healthcare staff for each channel. Results. There were 199 (4.56%) COVID-19-positive patients, of whom 80 (40%) were operated. COVID-19 positivity rate was low in Group 2 (3% vs. Group 1, 11%). There was no seroconversion from negative to positive in our patients during the peri-operative period. Conclusion. COVID-19 positivity rate in Group-2 was significantly less. None of the COVID-19-negative patients turned symptomatic and the probability of seroconversion from COVID-19-negative was less during the peri-operative period. The isolation protocol of non-COVID-19 positive patients with the separate channel is effective.