RMIT University

About: RMIT University is a education organization based out in Melbourne, Victoria, Australia. It is known for research contribution in the topics: Population & Health care. The organization has 40468 authors who have published 82923 publications receiving 1729499 citations. The organization is also known as: Royal Melbourne Institute of Technology & Melbourne Technical College.

A blinded, randomized clinical trial of mycophenolate mofetil for the prevention of acute rejection in cadaveric renal transplantation

Abstract: Mycopehenolate mofetil (MMF) is a powerful immunosuppressant that inhibits the proliferation of T and B lymphocytes by blocking the enzyme inosine monophosphate dehydrogenase. MMF has been shown to prevent acute graft rejection in animal experiments and may have an important role in clinical renal transplantation. We conducted a prospective, double-blind, multi-center trial to compare the efficacy and safety of MMF and azathioprine within standard immunosuppressive regimen for patients receiving a first or second cadaveric renal graft. A total of 503 patients were randomized to groups receiving MMF 3 g (n=164), MMF 2 g (n=173), or azathioprine (AZA) 100-150 mg (n=166) daily. All were treated simultaneously with equivalent doses of cyclosporine and oral corticosteroids and followed for 12 months. The primary endpoint was treatment failure, defined as the occurrence of biopsy-proven graft rejection, graft loss, patient death, or discontinuation of the study drug during the first 6 months after transplantation. Treatment failure occurred in 50.% of patients in the AZA group by 6 months after transplantation, compared with 34.8% in the MMF 3g group (P=0.0045) and 38.2 % in the MMF 2g group (P=0.0287). Biopsy-proven rejection occurred in 15.9% of patients in the MMF 3 g group and 19.7% in the MMF2 g group, compared with 35.5% in the AZA group. Rejection of histologic severity grade II or more developed in 6.1 %, 10.4% and 19.9% of patients in the MMF 3 g, MMF 2 g, and AZA groups, respectively. Patients receiving MMF required less frequent and less intensive treatment for acute rejection: 24.4% of patients on MMF 3 g and 31.0% on MMF 2 g were tested for acute rejection, compared with 47.5% on AZA. Only 4.9% on MMF 3 g and 8.8% on MMF 2 g required antilymphocyte antibodies for treatment of severe or steroid-resistant rejection, compared with 15.4% of the patients on AZA. At 1 year after transplantation, graft survival in the MMF groups was marginally superior to that in the AZA group, although this difference was not statistically significant. Gastrointestinal toxicity and tissue-invasive cytomegalovirus infection were more common in the MMF 3 g group. Noncutaneous malignancies occurred in six patients on MMF 3 g, three patients on MMF 2 g, and four patients on AZA. Lymphoproliferative disorders occurred in two patients per MMF group, compared with one patient receiving AZA. MMF appears to be an important advance in prophylaxis following renal transplantation. It is associated with a significantly lower rate of treatment failure compared with AZA during the first 6 months after renal transplantation and produces a clinically important reduction in the incidence, severity, and treatment of acute graft rejection. These differences persist throughout the first year of follow-up. Clinical benefit was greatest with a dose of MMF 3 g/day, but gastrointestinal effects, invasive cytomegalovirus infection, and malignancies were slightly more common at that dose. The appropriate dose may lie between 2 g and 3 g per day and may require individualization depending on clinical course or other factors.

Sliding-Mode Control for Systems With Mismatched Uncertainties via a Disturbance Observer

Abstract: This paper develops a sliding-mode control (SMC) approach for systems with mismatched uncertainties via a nonlinear disturbance observer (DOB). By designing a novel sliding surface based on the disturbance estimation, a DOB-based SMC method is developed in this paper to counteract the mismatched disturbance. The newly proposed method exhibits the following two attractive features. First, the switching gain is only required to be designed greater than the bound of the disturbance estimation error rather than that of the disturbance; thus, the chattering problem is substantially alleviated. Second, the proposed method retains its nominal performance, which means the proposed method acts the same as the baseline sliding-mode controller in the absence of uncertainties. Simulation results of both the numerical and application examples show that the proposed method exhibits much better control performance than the baseline SMC and the integral SMC (I-SMC) methods, such as reduced chattering and nominal performance recovery.

Impact on mental health and perceptions of psychological care among medical and nursing staff in Wuhan during the 2019 novel coronavirus disease outbreak: A cross-sectional study.

Abstract: The severe 2019 outbreak of novel coronavirus disease (COVID-19), which was first reported in Wuhan, would be expected to impact the mental health of local medical and nursing staff and thus lead them to seek help. However, those outcomes have yet to be established using epidemiological data. To explore the mental health status of medical and nursing staff and the efficacy, or lack thereof, of critically connecting psychological needs to receiving psychological care, we conducted a quantitative study. This is the first paper on the mental health of medical and nursing staff in Wuhan. Notably, among 994 medical and nursing staff working in Wuhan, 36.9% had subthreshold mental health disturbances (mean PHQ-9: 2.4), 34.4% had mild disturbances (mean PHQ-9: 5.4), 22.4% had moderate disturbances (mean PHQ-9: 9.0), and 6.2% had severe disturbance (mean PHQ-9: 15.1) in the immediate wake of the viral epidemic. The noted burden fell particularly heavily on young women. Of all participants, 36.3% had accessed psychological materials (such as books on mental health), 50.4% had accessed psychological resources available through media (such as online push messages on mental health self-help coping methods), and 17.5% had participated in counseling or psychotherapy. Trends in levels of psychological distress and factors such as exposure to infected people and psychological assistance were identified. Although staff accessed limited mental healthcare services, distressed staff nonetheless saw these services as important resources to alleviate acute mental health disturbances and improve their physical health perceptions. These findings emphasize the importance of being prepared to support frontline workers through mental health interventions at times of widespread crisis.

Topological-insulator-based terahertz modulator

Abstract: Three dimensional topological insulators, as a new phase of quantum matters, are characterized by an insulating gap in the bulk and a metallic state on the surface. Particularly, most of the topological insulators have narrow band gaps, and hence have promising applications in the area of terahertz optoelectronics. In this work, we experimentally demonstrate an electronically-tunable terahertz intensity modulator based on Bi1:5Sb0:5Te1:8Se1:2 single crystal, one of the most insulating topological insulators. A relative frequency-independent modulation depth of ~62% over a wide frequency range from 0.3 to 1.4 THz has been achieved at room temperature, by applying a bias current of 100 mA. The modulation in the low current regime can be further enhanced at low temperature. We propose that the extraordinarily large modulation is a consequence of thermally-activated carrier absorption in the semiconducting bulk states. Our work provides a new application of topological insulators for terahertz technology.