2,518 research outputs found
The Impacts of Role Overload and Role Conflict on Physicians\u27 Technology Adoption
Technology adoption is an important solution for physicians to increase work efficiency, and thus deal with role conflict among their multiple job roles. Prior studies have not investigated how multiple job roles and role conflict influence physicians’ technology adoption intentions. Based on role strain theory and role identity theory, we present a model of physicians’ technology adoption intentions to support their primary (clinical care) versus secondary (teaching or research) job roles. We test the model using surveys with 156 physicians at nine medical schools in Korea. The results of our data analysis largely support our hypotheses. Role overload in each of their job roles increases role conflict between any pair of associated roles. Furthermore, role conflict between a physician’s primary and secondary role is affected more by role overload in the secondary role than by overload in the primary role. Moreover, the impact of role conflict on technology adoption intentions is also influenced by the hierarchical relationship between two roles. This study contributes to technology adoption research by demonstrating how physicians’ job characteristics affect technology adoption
Extrusion-Based 3D Printing of Molecular Sieve Zeolite for Gas Adsorption Applications
Extrusion based 3D printing is one of the emerging additive manufacturing technologies used for printing range of materials from metal to ceramics. In this study, we developed a customized 3D printer based on extrusion freeform fabrication technique, such as slurry deposition, for 3D printing of different molecular sieve zeolite monoliths like 3A, 4A, 5A and 13X to evaluate their performance in gas adsorption. The physical and structural properties of 3D printed zeolite monoliths will be characterized along with the gas adsorption performance. The Brunauer–Emmett–Teller (BET) test of 3D printed samples will be performed for calculation of the surface area, which will give us the capacity of gas absorption into 3D printed zeolite. The BET surface area test showed good results for Zeolite 13X compared to available literature. The surface area calculated for 3D – printed Zeolite 13X was 767m2/g and available literature showed 498 m2/g for 3D – printed Zeolite 13X. The microhardness values of 3D – printed Zeolite samples were measured using a Vicker hardness tester. The hardness value of the 3D - printed Zeolite samples
increased from 8.3 ± 2 to 12.5 ± 3 HV 0.05 for Zeolite 13X, 3.3 ± 1 to 7.3 ± 1 HV 0.05 for Zeolite 3A, 4.3 ± 2 to 7.5 ± 2 HV 0.05 for Zeolite 4A, 7.4 ± 1 to 14.0 ± 0.5 HV 0.05 for Zeolite 5A, before and after sintering process, respectively. The SEM analysis was performed for 3D printed samples before and after sintering to evaluate their structural properties. The SEM analysis reveals that all 3D – printed Zeolite samples retained their microstructure after slurry preparation and also after the sintering process. The porous nature of 3D – printed Zeolite walls was retained after the sintering process
Glycemic Control Promotes Pancreatic Beta-Cell Regeneration in Streptozotocin-Induced Diabetic Mice
BACKGROUND: Pancreatic beta-cells proliferate following administration of the beta-cell toxin streptozotocin. Defining the conditions that promote beta-cell proliferation could benefit patients with diabetes. We have investigated the effect of insulin treatment on pancreatic beta-cell regeneration in streptozotocin-induced diabetic mice, and, in addition, report on a new approach to quantify beta-cell regeneration in vivo. METHODOLOGY/PRINCIPAL FINDINGS: Streptozotocin-induced diabetic were treated with either syngeneic islets transplanted under the kidney capsule or subcutaneous insulin implants. After either 60 or 120 days of insulin treatment, the islet transplant or insulin implant were removed and blood glucose levels monitored for 30 days. The results showed that both islet transplants and insulin implants restored normoglycemia in the 60 and 120 day treated animals. However, only the 120-day islet and insulin implant groups maintained euglycemia (<200 mg/dl) following discontinuation of insulin treatment. The beta-cell was significantly increased in all the 120 day insulin-treated groups (insulin implant, 0.69+/-0.23 mg; and islet transplant, 0.91+/-0.23 mg) compared non-diabetic control mice (1.54+/-0.25 mg). We also show that we can use bioluminescent imaging to monitor beta-cell regeneration in living MIP-luc transgenic mice. CONCLUSIONS/SIGNIFICANCE: The results show that insulin treatment can promote beta-cell regeneration. Moreover, the extent of restoration of beta-cell function and mass depend on the length of treatment period and overall level of glycemic control with better control being associated with improved recovery. Finally, real-time bioluminescent imaging can be used to monitor beta-cell recovery in living MIP-luc transgenic mice
Manganese based layered oxides with modulated electronic and thermodynamic properties for sodium ion batteries
Manganese based layered oxides have received increasing attention as cathode materials for sodium ion batteries due to their high theoretical capacities and good sodium ion conductivities. However, the Jahn–Teller distortion arising from the manganese (III) centers destabilizes the host structure and deteriorates the cycling life. Herein, we report that zinc-doped Na0.833[Li0.25Mn0.75]O2 can not only suppress the Jahn–Teller effect but also reduce the inherent phase separations. The reduction of manganese (III) amount in the zinc-doped sample, as predicted by first-principles calculations, has been confirmed by its high binding energies and the reduced octahedral structural variations. In the viewpoint of thermodynamics, the zinc-doped sample has lower formation energy, more stable ground states, and fewer spinodal decomposition regions than those of the undoped sample, all of which make it charge or discharge without any phase transition. Hence, the zinc-doped sample shows superior cycling performance, demonstrating that zinc doping is an effective strategy for developing high-performance layered cathode materials
Synthesis of large-area multilayer hexagonal boron nitride for high material performance
Although hexagonal boron nitride (h-BN) is a good candidate for gate-insulating materials by minimizing interaction from substrate, further applications to electronic devices with available two-dimensional semiconductors continue to be limited by flake size. While monolayer h-BN has been synthesized on Pt and Cu foil using chemical vapour deposition (CVD), multilayer h-BN is still absent. Here we use Fe foil and synthesize large-area multilayer h-BN film by CVD with a borazine precursor. These films reveal strong cathodoluminescence and high mechanical strength (Young’s modulus: 1.16±0.1 TPa), reminiscent of formation of high-quality h-BN. The CVD-grown graphene on multilayer h-BN film yields a high carrier mobility of ~24,000 cm[superscript 2] V[superscript −1] s[superscript −1] at room temperature, higher than that (~13,000 [superscript 2] V[superscript −1] s[superscript −1]) with exfoliated h-BN. By placing additional h-BN on a SiO[subscript 2]/Si substrate for a MoS[subscript 2] (WSe[subscript 2]) field-effect transistor, the doping effect from gate oxide is minimized and furthermore the mobility is improved by four (150) times.Korea Institute of Science and Technology. Institutional ProgramNational Science Foundation (U.S.) (STC Center for Integrated Quantum Materials Grant DMR-1231319)Massachusetts Institute of Technology. Institute for Soldier Nanotechnologie
Entropy of the Schwarzschild black hole to all orders in the Planck length
Considering corrections to all orders in the Planck length on the quantum
state density from a generalized uncertainty principle (GUP), we calculate the
statistical entropy of the scalar field on the background of the Schwarzschild
black hole without any cutoff. We obtain the entropy of the massive scalar
field proportional to the horizon area.Comment: 13 pages, 1 figure; Minor typos corrected, one reference added;
Accepted for publication in Phys. Lett.
TCF7L2 is a master regulator of insulin production and processing
Genome-wide association studies have revealed >60 loci associated with type 2 diabetes (T2D), but the underlying causal variants and functional mechanisms remain largely elusive. Although variants in TCF7L2 confer the strongest risk of T2D among common variants by presumed effects on islet function, the molecular mechanisms are not yet well understood. Using RNA-sequencing, we have identified a TCF7L2-regulated transcriptional network responsible for its effect on insulin secretion in rodent and human pancreatic islets. ISL1 is a primary target of TCF7L2 and regulates proinsulin production and processing via MAFA, PDX1, NKX6.1, PCSK1, PCSK2 and SLC30A8, thereby providing evidence for a coordinated regulation of insulin production and processing. The risk T-allele of rs7903146 was associated with increased TCF7L2 expression, and decreased insulin content and secretion. Using gene expression profiles of 66 human pancreatic islets donors', we also show that the identified TCF7L2-ISL1 transcriptional network is regulated in a genotype-dependent manner. Taken together, these results demonstrate that not only synthesis of proinsulin is regulated by TCF7L2 but also processing and possibly clearance of proinsulin and insulin. These multiple targets in key pathways may explain why TCF7L2 has emerged as the gene showing one of the strongest associations with T2
Higher dimensional flat embeddings of (2+1) dimensional black holes
We obtain the higher dimensional global flat embeddings of static, rotating,
and charged BTZ black holes. On the other hand, we also study the similar
higher dimensional flat embeddings of the (2+1) de Sitter black holes which are
the counterparts of the anti-de Sitter BTZ black holes. As a result, the
charged dS black hole is shown to be embedded in (3+2) GEMS, contrast to the
charged BTZ one having (3+3) GEMS structure.Comment: 16pages, revtex, no figures, to appear in Phys. Rev.
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