17 research outputs found
Explanatory Study of Women Working in the Management of Universities
The paper aims to investigate the gender in higher education andcareer experience of women academicians to understand the factors that undermine their career progression. The objectives of the study are to overview the existing situation of women and men in universities and to identify the barriers that cause the underepresentation of women. Both primary and secondary data was used in the study.Questionnaire (Quantitative method )was used to collect the data. The sample of the study consists of 120 women academician of three universities. The sample universities were AIOU, AJ&K and FJWU. Data was analysed through percentage,tabulation and graphs. The paper examined the factors such as work/family conflict, exclusion of women from policy formulation,facilities provided by organization, attitude of male superior and colleagues and difficulties to exercise authority over male.The findings show that work/family conflict and difficulties to exercise authority, exclusion of women from policy formulation are negatively impact on women’s career progression.This study provides an opportunity to develop an insight into the issue of women’s representation in academic and administrative positions in universities. The findings of this study may provide information to different working organizations. There are different projects and programs of ministry of education, ministry of women development. This research would be beneficial both for public and private universities. The study might serve to strengthen efforts to implement equal opportunities for women in the universities and encourage women to put themselves forward for appointment to management positions
Fatal elizabethkingia meningoseptica cholangitis following biliary stent placement
Elizabethkingia (E.) meningosepticais a ubiquitous gram-negative bacillus belonging to the genus Chryseobacteriumand has been reported to cause nosocomial infections in both the immunocompromised and immunocompetent patients. E. meningoseptica can colonize the biliary tree after endoscopic procedures; and cholangitis, caused by this organism, is associated with a favorable prognosis. Here, we report a fatal case of cholangitis secondary to E. meningoseptica that developed following biliary stent placement. This case suggests that E. meningoseptica can be a cause of potentially fatal biliary tract infections in patients who undergo biliary tract endoscopic procedures. Clinicians must not disregard this organism as a contaminant (or colonizer) as a delay in diagnosis and treatment can lead to a fatal outcome, as seen in this case
Proteinase 3-antineutrophil cytoplasmic antibody positive necrotizing vasculitis induced by ciprofloxacin
Granulomatosis with polyangiitis (Wegener’s), microscopic polyangitis, and eosinophilic granulomatosis with polyangiitis are commonly grouped together as antineutrophil cytoplasmic antibody (ANCA)-positive vasculitides. Many drugs and infections can induce serologic positivity for ANCA, while a few can precipitate overt ANCA-positive vasculitis. Although fluoroquinolones have been reported to cause ANCA-negative leukocytoclastic vasculitis (LCV), fluoroquinolones are not known to induce proteinase 3-ANCA (PR3-ANCA)-positive vasculitis. Here, we present the case of a middle-aged man who developed severe headache, purpura on legs and numbness in hands and feet after taking ofloxacin for 5 days. Subsequently, he was diagnosed with ANCA-negative LCV and treated with steroids and immunosuppressants. Thirteen years later, he inadvertently received intravenous ciprofloxacin and developed severe headache and epistaxis. Serologic testing at that time revealed elevated titers of PR3-ANCA. Biopsy of nasal septum revealed a mixed mononuclear and polymorphonuclear infiltrate without evidence of granuloma formation. He was treated with steroids and immunosuppressive therapy. Over the next several years, he remained stable with residual hearing loss and nasal septal deformity. This case provides the first evidence for a PR3-ANCA-positive necrotizing vasculitis induced by ciprofloxacin
Physicochemical and biological characterization of silica-coated alumina particles
ObjectivesA tribochemical silica-coating (TSC) method has been developed to improve the adhesion of dental resin composites to various substrates. The method utilizes airborne-particle abrasion using particles having a silica surface and an alumina core. The impact of the TSC method has been extensively studied but less attention has been paid to the characterization of the silica-modified alumina particles. Due to the role of silicate ions in cell biology, e.g. osteoblast function and bone mineralization, silica-modified alumina particles could also be potentially used as a biomaterial in scaffolds of tissue regeneration. Thus, we carried out detailed physicochemical characterization of the silica-modified alumina particles.MethodsSilica-modified alumina particles (Rocatec, 3 M-ESPE) of an average particle size of 30 µm were studied for the phase composition, spectroscopic properties, surface morphology, dissolution, and the capability to modify the pH of an immersion solution. The control material was alumina without silica modification. Pre-osteoblastic MC3T3-E1 cells were used to assess cell viability in the presence of the particles. Cell viability was tested at 1, 3, 7 and 10 days of culture with various particle quantities. Multivariate ANOVA was used for statistical analyses.ResultsMinor quantities of silica enrichment was verified on the surface of alumina particles and the silica did not evenly cover the alumina surface. In the dissolution test, no change in the pH of the immersion solution was observed in the presence of the particles. Minor quantities of silicate ions were dissolved from the particles to the cell culture medium but no major differences were observed in the viability of pre-osteoblastic cells, whether the cells were cultured with silica-modified or plain alumina particles.SignificanceCharacterization of silica-modified alumina particles demonstrated differences in the particle surface structure compared to control alumina. Dissolution of silica layer in Tris buffer or SBF solution varied from that of cell culture medium: minor quantities of dissolved Si were observed in cell culture test medium. The cell viability test did not shown significant differences between control alumina and its silica-modified counterpart.</p
Structural and elemental characterization of glass and ceramic particles for bone surgery
AbstractObjectiveClinically used bioceramics have been characterized previously with different kinds of methods and comparison of results have proven to be difficult due to varieties of the material properties of interest. Therefore, in this study we compared clinically commonly used bioceramics of hydroxyapatite and carbonate apatite, two bioactive glasses 45S5 and S53P4, and alumina with respect of properties which according to the present knowledge are significant for bone biology.MethodsPhysicochemical properties of the materials were characterized by various methods. Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) was used to analyze the material vibrational features. X-ray Power Diffraction (XRD) was used to characterize the material crystal structure and scanning electron microscopy-energy-dispersive x-ray analysis (SEM-EDXA) was used to evaluate the morphology and size of the materials and to calculate their oxide content. The dissolution behavior of the materials, ion release and pH changes in Tris buffer in a continuous flow-through reaction for 24-hours were determined. The change of the surface of the bioactive glasses by interfacial reaction during the Tris immersion was examined and the thickness of the surface reaction layer of the materials was studied.ResultsSEM examination showed that the particle morphology of BG 45S5, BG S53P4 and alumina particle’s surface was smooth. The surface of HAP was porous, but also CAP showed some surface porosity. An increase in the pH of the immersion solution was observed especially for BG 45S5 and BG S53P4. HAP, CAP and alumina caused only a minor increase in pH. BGs 45S5 and S53P4 showed a rapid initial release of sodium and calcium ions, followed by the release of silicon species. Minor release of sodium ions was registered for HAP, CAP and alumina. Calcium ion release was low but constant over the experimental time while only a minor initial dissolution was measured for HAP.SignificanceThe in vitro study showed differences in the materials’ properties, which are considered to be important for biological suitability and in clinical applications, such as materials tomography, ion release and pH changes.</p
The Potential Effect of Annealing Mesostructured Titanium Dioxide Electrode in a Closed Box Furnace on the Concentration of Lead (II) Iodide Solution Required for Optimal Performance of Mesoscopic Perovskite Solar Cells
Highly reproducible mesoscopic perovskite solar cells (PSCs) can be fabricated using two-step sequential deposition of organo-lead halide (perovskite) active layer. However, differences in the processing conditions of individual layers which are subsequently assembled to construct the ultimate device can result in variations in the solar cell performance. For instance, here we report trends in the device performance as a function of PbI2 solution concentration, where the compact and mesoporous TiO2 layers were annealed in a closed box furnace (instead of doing it in open air). We observed that the devices prepared using 1.2 M PbI2 solution concentration performed better than those prepared from 0.8 M and 1 M PbI2 solutions. Generally, the researchers use the hot plate in an open-air environment or use a special hot plate where a continuous flow of air is ensured while annealing TiO2 electron selective layers (ESL) for perovskite solar cells. In this case, the highest possible device efficiencies are achieved using 1 M concentration of PbI2 solution. Although the influence of PbI2 solution concentration has been previously studied in detail, here our prime focus is to briefly comment on slight differences in the device performance trends which we observed in comparison to the previously reported results, where TiO2 layers were calcined in open air
The Potential Effect of Annealing Mesostructured Titanium Dioxide Electrode in a Closed Box Furnace on the Concentration of Lead (II) Iodide Solution Required for Optimal Performance of Mesoscopic Perovskite Solar Cells
Highly reproducible mesoscopic perovskite solar cells (PSCs) can be fabricated using two-step sequential deposition of organo-lead halide (perovskite) active layer. However, differences in the processing conditions of individual layers which are subsequently assembled to construct the ultimate device can result in variations in the solar cell performance. For instance, here we report trends in the device performance as a function of PbI2 solution concentration, where the compact and mesoporous TiO2 layers were annealed in a closed box furnace (instead of doing it in open air). We observed that the devices prepared using 1.2 M PbI2 solution concentration performed better than those prepared from 0.8 M and 1 M PbI2 solutions. Generally, the researchers use the hot plate in an open-air environment or use a special hot plate where a continuous flow of air is ensured while annealing TiO2 electron selective layers (ESL) for perovskite solar cells. In this case, the highest possible device efficiencies are achieved using 1 M concentration of PbI2 solution. Although the influence of PbI2 solution concentration has been previously studied in detail, here our prime focus is to briefly comment on slight differences in the device performance trends which we observed in comparison to the previously reported results, where TiO2 layers were calcined in open air
(Calcium-Phosphate)/Carrageenan Gardens Grown from the Gel/Liquid Interface
In this study, a gel/liquid interface is utilized for growing a new (calcium-phosphate)/carrageenan garden. The hydrogels are made from carrageenan loaded with either sodium phosphate or calcium chloride, while the interfaced solution contains a source of the salt not used in the hydrogels (i. e. the sodium-phosphate hydrogel with the calcium-chloride solution and vice versa). The physical and chemical properties of tubes grown from both systems of the same amount of carrageenan have been reported. Interestingly, when varying the amounts of carrageenan (and thus controlling the stiffness of the phosphate-hydrogel system), it is possible to control the thickness and height of the tubes.Peer reviewe
Highly Conductive Charge Transport Layers Impair Charge Extraction Selectivity in Thin‐Film Solar Cells
Charge selective interlayers are crucial in thin-film photovoltaics, such as
organic and Perovskite solar cells. Charge transporting layers (doped and
undoped) constitute perhaps the most important class of charge selective
interlayers; however, it is not well understood how a charge transporting layer
should be designed in order to ensure efficient extraction of majority carriers
while blocking minority carriers. This work clarifies how well
charge-transporting layers with varying majority carrier conductivities block
minority carriers. We use the Charge Extraction by a Linearly Increasing
Voltage technique to determine the surface recombination velocity of minority
carriers in model system devices with varying majority carrier conductivity in
the transporting layer. Our results show that transporting layers with high
conductivity for majority carriers do not block minority carriers - at least
not at operating voltages close to or above the built-in voltage, due to direct
bi-molecular recombination across the transporting layer-absorber layer
interface. We furthermore discuss and propose design principles to achieve
selective charge extraction in thin film solar cells using charge transporting
layers
Manganese Doping Promotes the Synthesis of Bismuth-based Perovskite Nanocrystals While Tuning Their Band Structures
The doping of halide perovskite nanocrystals (NCs) with manganese cations (Mn2+) has recently enabled enhanced stability, novel optical properties, and modulated charge carrier dynamics of the NCs host. However, the influence of Mn doping on the synthetic routes and the band structures of the host has not yet been elucidated. Herein, it is demonstrated that Mn doping promotes a facile, safe, and low-hazard path toward the synthesis of ternary Cs3Bi2I9 NCs by effectively inhibiting the impurity phase (i.e., CsI) resulting from the decomposition of the intermediate Cs3BiI6 product. Furthermore, it is observed that the deepening of the valence band level of the host NCs upon doping at Mn concentration levels varying from 0 to 18.5% (atomic ratio) with respect to the Bi content. As a result, the corresponding Mn-doped NCs solar cells show a higher open-circuit voltage and longer electron lifetime than those employing the undoped perovskite NCs. This work opens new insights on the role of Mn doping in the synthetic route and optoelectronic properties of lead-free halide perovskite NCs for still unexplored applications.publishedVersionPeer reviewe