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31.
Halimatus Sakdiah Minhat Hazwan Mat Din Raja Nurzatul Efah Raja Adnan 《International Journal of Mental Health Promotion, The》2021,23(3):409-416
Population ageing puts pressure on the workforce and increase the demands for aged workforce. The demographic shifts have made the issue of healthier workers, especially those of advanced age and physically related
job scopes, a fundamental aspect to employing older workers. Hence, this study aimed to explore the best practices to employ older adults into the social care sector. The social care sector was chosen in view of the nature of
job and declining demand among younger workers. A qualitative study was conducted involving series of focus
group discussions (FGD) with social care workers of long-term care centers in the peninsular Malaysia. Data was
collected using a validated and pre-tested semi-structured interview protocol. Each focus group discussions and
in-depth interviews were lasted between 45 min to 1 h. A total of 57 workers were consented for the study which
was divided into young and old workers based on the mean age of 41.43 [SD ± 9.97] years old. The content of the
interviews was transcribed verbatim and thematic analysis was performed to inductively identify the coding and
themes within the data related to the challenges employing older workers into the social care sector. Three categories of coding were identified (individual, environmental and management factors), leading to the identification
of two important themes which are healthy workplace and work autonomy. The findings indicate the needs for
work culture transformations to cultivate healthy working environment and freedom of speech particularly
among the older workers. 相似文献
32.
Background
Due to the steadily increasing incidence of atopic dermatitis, there is a great medical need for new therapies and improved animal models.Objective
To provide more detailed analysis of a Sprague–Dawley rat dermatitis model.Methods
Sprague–Dawley rats were actively sensitized by intraperitoneal injections of dinitrophenylated ovalbumin (DNP-OVA) plus alum. Skin reactions were elicited by repeated epicutaneous challenge with 2,4-dinitrofluorobenzene (DNFB).Results
The ear thickness exhibited a significant increase from the first challenge. A relatively steep increase in ear thickness was observed at the fifth DNFB application. After the fifth DNFB application, total serum immunoglobulin (Ig) E and IgG1 levels reached a plateau at 1 h compared with the normal group. The peak production of tumor necrosis factor (TNF)-α and monocyte chemoattractant protein (MCP)-1 was found at 1 h, while that of intercellular adhesion molecule (ICAM)-1 was found at 24 h. Infiltration of CD4+ T cells, CD8+ T cells, eosinophils and mast cells increased in the skin lesion.Conclusions
The indices such as thickness and inflammatory cell infiltration in the lesional skin were increased by repeated hapten application; TNF-α, MCP-1 and ICAM-1 increased with the development of the dermatitis. 相似文献33.
Means of controlling or even improving the safety of food products is to decontaminate the carcasses or products during or at the end of the production line. The decontamination of meat and poultry can help to reduce human foodborne infections. However, process hygiene to prevent contamination should never be neglected. Some techniques of decontaminating raw meat and poultry meat products are discussed in this review. 相似文献
34.
Zaheer Ud Din Babar Jameela Fatheema Nimrah Arif M. S. Anwar Sundus Gul Mudassir Iqbal Syed Rizwan 《RSC advances》2020,10(43):25669
Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications. There are many promising applications of MXenes; however, their magnetic properties lack a wide margin, both experimentally as well as theoretically, which needs to be investigated for potential use in spintronics. In this study, we carried out a comprehensive etching process via selective extraction of Al layers from Nb2AlC-MAX using a wet electrochemical route under well-optimized conditions to obtain fine 2D-Nb2C MXene sheets. Structural analysis using X-ray diffraction (XRD) confirms the effective removal of Al followed by confirmation of a 2D layered structure from morphological analysis using scanning electron microscopy (SEM). Zero-field-cooled (ZFC) and field-cooled (FC) measurements of MAX and MXene at different field strengths were performed using a superconducting quantum interference device (SQUID). Magnetic measurements reveal the paramagnetic nature of Nb2AlC-MAX measured under 5 mT; however, this changes to a clear superconductor-like diamagnetic behavior with a shift of the magnetization from positive to negative values at low temperatures when measured under 5 mT and 10 mT for Nb2C MXene. The diamagnetism, however, is changed to paramagnetism at 100 mT, which shows the existence of critical fields known typically for a type-II superconductor. To gain an insight into this unusual behavior in MXene, density functional theory (DFT) first-principles calculation was also performed in Wein2K software using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be negative, which corresponds well with the experimental finding and suggests that the negative magnetic moment originated from the d-orbital of Nb2C. The present report provides a pathway to deeply understanding the existence of superconductivity-like diamagnetic behavior in Nb2C MXene, which is useful for future magnetic applications.Transition metal carbides (TMCs) have recently emerged as competent members among the family of two-dimensional (2D) materials, owing to their promising applications.In two-dimensional (2D) materials, magnetism at the nanoscale is at the forefront of many cutting-edge technological applications, such as spintronic devices. Naguib et al. have synthesized a new class of two-dimensional materials, known as MXenes (MnXn+1), discovered in 2011, giving a possibility of magnetism in such 2D materials and their promising uses in spintronic devices.1 These 2D layer structured early transition metal carbides and/or nitrides are known as MXenes, so named to indicate their structural similarities with graphene.2 MXenes are derived from 3D MAX phases (space group P63/mmc) in which “M” is an early transition metal, e.g., Ti, Ta, V, etc.; “A” is mainly a group 13 or group 14 element (group III-A or IV-A), e.g., Si, Al; “X” is a carbide, nitride or can be both; and n = 1, 2, 3 represents the number of layers, forming 211, 312 and 413 phases.3–5 Over the past decade, this new material has gained enormous attention, thus developing an entirely new research field to disclose the properties of the 2D state of this material. The materials in the 2D regime own a cluster of astonishing physical properties as compared to the 3D nature, but intrinsic two-dimensional magnetism has proved to be challenging. As 2D semiconductors have revamped the field of electronics, similarly, magnetism in 2D materials could remodel spintronic devices that can employ a spin degree of freedom.6,7Nb2C MXene was first synthesized by Naguib et al., but they just reported its electrochemical activity as a promising electrode material.4 Further work has been reported in Nb2C with various biomedical applications, energy storage, supercapacitors, and nanoelectronics.9–19 As far as the magnetism in such 2D MXenes is concerned, it remains less investigated, and this research void needs to be filled. Recently, Babar et al. reported the observation of superconductivity in as-prepared powdered Nb2C for the first time, with the highest onset transition temperature Tc,onset = 12.5 K among the MXene family. However, the authors did not discuss the magnetic nature of the parent Nb2AlC MAX itself and did not reason for the presence of unusual magnetic effects in MXene.8 MXenes are favorable members of 2D magnetism, and different magnetic natures are computationally predicted in various carbide and nitride MXenes.7,20 The existence of novel room-temperature ferromagnetic order in doped MXene and the coexistence of different magnetic phases in MXene, along with experimental evidence, indicate its potential of hosting diverse magnetic natures.21,22 Considerable research has been focused on these 2D structures due to their importance and favorable applications, such as spintronics. MXene could provide a vast platform for exploring the magnetic properties and is one of the best candidates that can host superconductivity as compared to other members of the 2D family. Experimental studies are generally dependent upon numerous variables, thus affecting the research pace. However, density functional theory-based first principles calculation and theoretical simulations are a successful way to examine and foresee the properties of low-dimensional materials. This provoked us to theoretically explore superconductivity in Nb2C and their validation through superconductivity measurements of experimentally synthesized Nb2C MXene. In this work, we report a systematic etching mechanism of Nb2C MXene to obtain fine 2D sheets via a chemical etching route using hydrofluoric (HF) acid. Structural and morphological studies using the X-ray diffraction technique (XRD), scanning electron microscopy (SEM) and elemental analysis by energy-dispersive X-ray spectroscopy (EDX) show the effective removal of Al from the parent 3D-Nb2AlC MAX, thus revealing an accordion-like sheet structure. Optical analysis indicates a significant reduction in bandgap after chemical etching. Magnetic properties were carried out to observe the signatures of superconductivity (a perfect diamagnetic state, negative magnetic moment) and its magnetic nature at room temperature. To study the magnetic nature of as-prepared powder-form Nb2C, density functional theory (DFT) first principles calculation was carried out through Wein2K using spin-polarized generalized gradient approximation (sp-GGA). The magnetic moment of the compound is calculated to be −0.00485, which although but small is important, as the value is negative, which is an indication of the presence of diamagnetism in Nb2C. Here, the detailed chemical etching process, magnetic properties of Nb2AlC MAX and its effect on magnetic phase of Nb2C MXene, and the density functional theory calculation are reported, which were not discussed by Babar et al. in ref. 8. 相似文献
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39.
Helicobacter pylori eradication lowers esophageal sphincter pressures in functional dyspepsia patients 总被引:2,自引:0,他引:2
Besisik F Sürücü F Mungan Z Dinçer D Kapran Y Kaymakoglu S Cevikbas U 《Hepato-gastroenterology》2001,48(42):1772-1775
BACKGROUND/AIMS: Helicobacter pylori infection is the most common cause of gastroduodenal diseases. The role H. pylori eradication in functional dyspepsia patients is contradictory. We performed this study to determine the effects of H. pylori eradication in functional dyspepsia patients with respect to physiological and histological parameters including esophageal sphincter functions. METHODOLOGY: We studied 20 functional dyspepsia patients, whose H. pylori infection was confirmed by histology and urease test. We also confirmed eradication using the same methods after three months. We performed 24-hour esophageal pH monitoring, esophageal manometry, meal stimulated gastrin release test and measured dyspepsia severity score and gastric emptying time before and three months after eradication. Eradication regimen consisted of omeprazol 20 mg b.i.d., clarithromycin 500 mg b.i.d. and metranidazol 500 mg b.i.d., for two weeks. Gastric inflammation and H. pylori density within biopsy samples from the antrum (n = 4), corpus (n = 4), cardia (n = 2), fundus (n = 2), duodenum (n = 2) and distal esophagus (n = 1) were assessed. RESULTS: Dyspepsia severity score (P < 0.001), meal stimulated gastrin levels, upper (P = 0.01) and lower (P = 0.06) sphincter pressures were decreased after eradication irrespective of gastric histology; but gastric emptying times (P = 0.87) and pH < 4.5% reflux (P = 0.91) were not changed significantly. CONCLUSIONS: H. pylori eradication results in decreased esophageal sphincter pressures irrespective of gastric histology in functional dyspepsia patients. These decreases are not associated with increased objective reflux or reflux symptomatology. The clinical significance of these finding deserves further evaluations. 相似文献
40.
De Novo 17q24.2–q24.3 microdeletion presenting with generalized hypertrichosis terminalis,gingival fibromatous hyperplasia,and distinctive facial features 下载免费PDF全文