116 research outputs found
A Pilot Investigation of Occupational Therapy Students’ Perceptions of Their Impact on Services to Older Adults
Practice education is an integral component of occupational therapy curricula to ensure graduates are competent in delivering effective and efficient services to their clients. This study aimed to understand occupational therapy students’ perceptions of the impact of student-delivered services for clients aged over 65 years. A case study design directed at in-depth exploration of undergraduate occupational therapy student experiences of working with older adults was employed. Semi-structured interviews were conducted with eight final-year students at an Australian university during 2015. Data were analysed using thematic analysis. The key finding was that students generally believed they contributed positively to aspects of client-services during placements. Students reported on the development of competence during placement and the positive impact they had on services for older adults. The study highlighted the unique intergenerational relationship students had with older adults during their therapeutic encounters. However, very few participants recognised the importance and complexity of providing holistic services to older adults. Conclusion: There is potential to improve services for older adults by offering a greater number of placement opportunities involving students in direct client services. If occupational therapy students are better prepared, supported, and informed of the complexities associated with working with older adults, direct client-services rendered by students could potentially be enhanced. This will require ongoing collaboration between occupational therapy workforce, placement sites, and universities to align occupational therapy curricula with healthcare needs
On reducing mesh delay for peer-to-peer live streaming
Peer-to-peer (P2P) technology has emerged as a promising scalable solution for live streaming to large group. In this paper, we address the design of overlay which achieves low source-to-peer delay, is robust to user churn, accommodates of asymmetric and diverse uplink bandwidth, and continuously improves based on existing user pool. A natural choice is the use of mesh, where each peer is served by multiple parents. Since the peer delay in a mesh depends on its longest path through its parents, we study how to optimize such delay while meeting a certain streaming rate requirement. We first formulate the minimum delay mesh problem and show that it is NP-hard. Then we propose a centralized heuristic based on complete knowledge which serves as our benchmark and optimal solution for all the other schemes under comparison. Our heuristic makes use of the concept of power in network given by the ratio of throughput and delay. By maximizing the network power, our heuristic achieves very low delay. We then propose a simple distributed algorithm where peers select their parents based on the power concept. The algorithm makes continuous improvement on delay until some minimum delay is reached. Simulation results show that our distributed protocol performs close to the centralized one, and substantially outperforms traditional and state-of-the-art approaches
(Z)-N-{(E)-10-[(2,6-DiisopropylÂphenÂyl)Âimino]-9,10-dihydroÂphenanthren-9-ylÂidene}-2,6-dimethylÂaniline
The title compound, C34H34N2, adopts a Z,E configuration with respect to the N=C—C=N backbone, with an N—C—C—N torsion angle of 41.1 (4)° The dihedral angle between the benzene rings in the 9,10-dihydroÂphenanthrene moiety is 18.0 (1)°
Discrete time crystal in an open optomechanical system
The spontaneous breaking of time translation symmetry in periodically driven
Floquet systems can lead to a discrete time crystal. Here we study the
occurrence of such dynamical phase in a driven-dissipative optomechanical
system with two membranes in the middle. We find that, under certian
conditions, the system can be mapped to an open Dicke model and realizes a
superradianttype phase transition. Furthermore, applying a suitable
periodically modulated drive, the system dynamics exhibits a robust subharmonic
oscillation persistent in the thermodynamic limit
Molecular cloning, expression, and immobilization of glutamate decarboxylase from Lactobacillus fermentum YS2
Background: GABA (\u3b3-aminobutyric acid) is a four-carbon nonprotein
amino acid that has hypotensive, diuretic, and tranquilizing
properties. Glutamate decarboxylase (GAD) is the key enzyme to generate
GABA. A simple and economical method of preparing and immobilizing
GADwould be helpful for GABA production. In this study, the GAD from
Lactobacillus fermentum YS2 was expressed under the control of a
stress-inducible promoter and was purified and immobilized in a fusion
form, and its reusability was investigated. Results: The fusion protein
CBM-GAD was expressed in Escherichia coli DH5\u3b1 carrying
pCROCB-gadB, which contained promoter PrpoS, cbm3 (family 3
carbohydrate-binding module from Clostridium thermocellum ) coding
sequence, the gadB gene from L. fermentum YS2 coding for GAD, and the
T7 terminator. After a one-step purification of CBM-GAD using
regenerated amorphous cellulose (RAC) as an adsorbent, SDS-PAGE
analysis revealed a clear band of 71 kDa; the specific activity of the
purified fusion protein CBM-GAD reached 83.6 \ub1 0.7 U\ub7mg-1.
After adsorption onto RAC, the immobilized GAD with CBM3 tag was
repeatedly used for GABA synthesis. The protein-binding capacity of RAC
was 174 \ub1 8 mg\ub7g-1. The immobilized CBM-GAD could repeatedly
catalyze GABA synthesis, and 8% of the initial activities was retained
after 10 uses. We tested the conversion of monosodium glutamate to GABA
by the immobilized enzyme; the yield reached 5.15 g/L and the
productivity reached 3.09 g/L\ub7h. Conclusions: RAC could be used as
an adsorbent in one-step purification and immobilization of CBM-GAD,
and the immobilized enzyme could be repeatedly used to catalyze the
conversion of glutamate to GABA
Macrophages Phenotype Regulated by IL-6 Are Associated with the Prognosis of Platinum-Resistant Serous Ovarian Cancer: Integrated Analysis of Clinical Trial and Omics
Background. The treatment of platinum-resistant recurrent ovarian cancer (PROC) is a clinical challenge and a hot topic. Tumor microenvironment (TME) as a key factor promoting ovarian cancer progression. Macrophage is a component of TME, and it has been reported that macrophage phenotype is related to the development of PROC. However, the mechanism underlying macrophage polarization and whether macrophage phenotype can be used as a prognostic indicator of PROC remains unclear. Methods. We used ESTIMATE to calculate the number of immune and stromal components in high-grade serous ovarian cancer (HGSOC) cases from The Cancer Genome Atlas database. The differential expression genes (DEGs) were analyzed via protein–protein interaction network, Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) analysis to reveal major pathways of DEGs. CD80 was selected for survival analysis. IL-6 was selected for gene set enrichment analysis (GSEA). A subsequent cohort study was performed to confirm the correlation of IL-6 expression with macrophage phenotype in peripheral blood and to explore the clinical utility of macrophage phenotype for the prognosis of PROC patients. Results. A total of 993 intersecting genes were identified as candidates for further survival analysis. Further analysis revealed that CD80 expression was positively correlated with the survival of HGSOC patients. The results of GO and KEGG analysis suggested that macrophage polarization could be regulated via chemokine pathway and cytokine–cytokine receptor interaction. GSEA showed that the genes were mainly enriched in IL-6-STAT-3. Correlation analysis for the proportion of tumor infiltration macrophages revealed that M2 was correlated with IL-6. The results of a cohort study demonstrated that the regulation of macrophage phenotype by IL-6 is bidirectional. The high M1% was a protective factor for progression-free survival. Conclusion. Thus, the macrophage phenotype is a prognostic indicator in PROC patients, possibly via a hyperactive IL-6-related pathway, providing an additional clue for the therapeutic intervention of PROC
Augmented Rac1 Expression and Activity are Associated with Oxidative Stress and Decline of β Cell Function in Obesity
Covalent Heterojunctions Enhance Bi2S3/Reduced Graphene Oxide (rGO) Nanocomposite Performance as Aqueous Zinc Ion Battery Material
The shortage of lithium resources, safety and recycling difficulty has focused attention on alternative energy storage devices in recent years. The aqueous zinc-ion battery (ZIB) stands out against such a background because of its earth abundance, safety, and environmental friendliness.1 However, the limited choice of cathode materials hinders the development of advanced high-energy-density aqueous ZIBs. At present, manganese oxide2 and vanadium oxide3 are the two most widely studied zinc-ion battery cathodes, but the migration of Zn2+ in these materials is limited by the strong electrostatic interaction with lattice oxygen ions, resulting in poor reversible capacity. Metal sulfides, instead, may effectively improve the electrochemical performance reversibility of ZIBs. Layered metal sulfides have been extensively studied in monovalent cation (Li+, Na+, K+) rechargeable batteries.4 However, although limited studies with Bi2S35,6 as ZIB cathode material exist, their detailed electrochemical charge storage and transfer mechanisms are not well understood. In this work, we explore the effect of covalent anchoring Bi2S3 on reduced graphene oxide (rGO) on the stability and cycling performance as a cathode for aqueous ZIBs. During the hydrothermal synthesis, the reduced graphene oxide serves as the nucleation substrate enabling the formation of fine and uniformly sized Bi2S3 grains, Figure 1 (a). Raman and X-ray photoelectron spectroscopy (XPS) confirm the formation of Bi-O-C heterojunctions during hydrothermal synthesis. These oxygen bridges serve as efficient electron transfer channels in the Bi2S3/rGO composite for rapid charge compensation during Zn2+ incorporation/extraction. As a result, Bi2S3/rGO composite shows notably better rate performance and cycling stability compared with pristine Bi2S3. The specific capacity of Bi2S3-rGO8 composite is ~186 mAh g-1 at the current density of 500 mA g-1 after 150 cycles, considerably higher than unsupported Bi2S3. Additionally, the Bi2S3 nucleated on GO with smaller particle sizes can shorten the transport path of zinc ions, which is beneficial for fast charge transfer. Therefore, Bi2S3-rGO8 can deliver more than 100 mAh g-1 at 10 A/g charge/discharge current density, Figure 1 (b). Also, the zinc storage mechanism was analyzed by X-ray diffraction spectroscopy (XRD) and XPS, indicating a reversible conversion reaction of Zn2+ in the Bi2S3-rGO framework. During discharging, Zn2+ is embedded in Bi2S3-rGO frame to form ZnS and Bi wrapped in rGO. The process is accompanied by the dissolution of bismuth into electrolyte and the formation of (ZnSO4)[Zn(OH)2]3·5H2O (ZHS) on the electrode surface. Inhibition of these two processes may further increase the cycle stability of Bi2S3-rGO. Rotating ring disc electrode (RRDE) measurements, in which we detect dissolved Bi, indicate that Bi dissolution in the electrolyte during charging/discharging is mitigated in Bi2S3/rGO electrode, compared to pristine Bi2S3
Loss of Angiotensin-Converting Enzyme 2 Exacerbates Diabetic Retinopathy by Promoting Bone Marrow Dysfunction
Angiotensin-converting enzyme 2 (ACE2) is the primary enzyme of the vasoprotective axis of the renin angiotensin system (RAS). We tested the hypothesis that loss of ACE2 would exacerbate diabetic retinopathy by promoting bone marrow dysfunction. ACE2-/y were crossed with Akita mice, a model of type 1 diabetes. When comparing the bone marrow of the ACE2-/y-Akita mice to that of Akita mice, we observed a reduction of both short-term and long-term repopulating hematopoietic stem cells, a shift of hematopoiesis towards myelopoiesis, and an impairment of lineage-c-kit+ hematopoietic stem/progenitor cell (HS/PC) migration and proliferation. Migratory and proliferative dysfunction of these cells was corrected by exposure to angiotensin-1–7 (Ang-1–7), the protective peptide generated by ACE2. Over the duration of diabetes examined, ACE2 deficiency led to progressive reduction in electrical responses assessed by electroretinography and to increases in neural infarcts observed by fundus photography. Compared to Akita mice, ACE2-/y-Akita at 9-months of diabetes showed an increased number of acellular capillaries indicative of more severe diabetic retinopathy. In diabetic and control human subjects, CD34+ cells, a key bone marrow HS/PC population, were assessed for changes in mRNA levels for MAS, the receptor for Ang-1–7. Levels were highest in CD34+ cells from diabetics without retinopathy. Higher serum Ang-1–7 levels predicted protection from development of retinopathy in diabetics. Treatment with Ang-1–7 or alamandine restored the impaired migration function of CD34+ cells from subjects with retinopathy. These data support that activation of the protective RAS within HS/PCs may represent a therapeutic strategy for prevention of diabetic retinopathy
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