Investigation of botulism in free-range duck farming in the Mekong Delta, Vietnam

Background: One of the most common diseases in free-range ducks in the Mekong Delta is botulism. Botulism is a poultry disease caused by botulinum exotoxin of Clostridium botulinum. Aim: To evaluate the prevalence of botulism in free-range ducks in the Mekong Delta and the risk of infection by determining the presence of C. botulinum in the farming environment. Methods: Research was carried out on 200 duck flocks with 187,050 individuals raised freely in the fields in the provinces of the Mekong Delta, including An Giang, Can Tho, Hau Giang, and Kien Giang. The ducks were diagnosed with botulism based on clinical symptoms. To demonstrate the presence of botulinum neurotoxins and identify serotype, samples of serum and/or gut were analyzed by mouse bioassay. Samples of soil (n = 600), water (n = 600), crabs (n = 216), and snails (n = 400) were taken from the grazing regions for C. botulinum analysis by PCR assay. Results: There were 1.19% (2,235/187,050) free-range ducks in the Mekong Delta positive for botulism. Clinical symptoms of botulism including limberneck, drooping eyelids–enlarged pupils, and leg paralysis were prevalent across free-range ducks, with the frequency of 87.92% (1,965/2,235), 90.07% (2,013/2,235), and 79.78% (1,783/2,235), respectively. The lesions of pulmonary edema–hemorrhage, hemorrhagic liver, and gas-producing intestines were common, accounting for 86.19% (362/420), 95.48% (401/420), and 92.14% (387/420), respectively. Botulin toxin type C was found in a considerable number of serum samples, accounting for 40.48% (51/126). Meanwhile, the percentage of serum samples containing botulin toxin types E and D was 28.57% (36/126) and 25.40% (32/126), respectively. Clostridium botulinum was detected in the farming environment specifically 17.5% (105/600) in soil, 19.67% (118/600) in water, 8.33% (18/216) in crabs, and 3.00% (12/400) in snails. Conclusion: The free-range ducks in the Mekong Delta were at high risk of botulism because of the latent presence of C. botulinum in the farming environment

Development and validation of control methods for an actuation system in a morphing wing and aileron system

Morphing wing technology is one of the most efficient approaches to reduce fuel consumption and air pollution. The project, called “CRIAQ MDO 505”, was created to explore and evaluate the morphing wing technology. A wing tip system composed of a wing and an aileron was designed and manufactured by the CRIAQ team at the LARCASE. In the context of this project, an optimization approach was studied to improve the aerodynamic performance by changing a wing’s shape. Different methodologies were applied to control four internal actuators attached inside the morphing wing. These actuators morph the upper skin of the wing so that the transition region moves from the wing leading edge to its trailing edge. The research presented here is a part of the MDO 505 project. The aim of this research is to model, simulate and validate the control methods for the wing-tip morphing control system. ANFIS (Adaptive Neuro-Fuzzy Inference System), an adaptive control algorithm, was selected for the morphing wing-tip control. A combination of neural networks and adaptive fuzzy control, ANFIS takes advantage of the fuzzy inference system (FIS) and of the selflearning abilities of the neural network, and thus offers a promising approach for the stability and accuracy of the proposed control system. The simulation and experimental results were acquired using National Instruments (NI) Veristand, Maxon drives and MATLAB/Simulink software. Experimental tests were carried out at the IAR-NRC Wind Tunnel in Ottawa to validate the simulation results. The results showed the potential for applying intelligent control methods to improve the performance of aircraft using morphing wing technology

Stakeholder engagement in late-stage translation phase 4 research for noncommunicable diseases in low- and middle-income countries : what works and why—the Vietnam experience (UMMS–Vietnam Team)

Background: Stakeholder engagement is crucial for conducting high-quality implementation research as well as for the incorporation and adoption of health interventions and policies in the community. Objectives: This study sought to build a mutually rewarding collaboration between stakeholders in Vietnam and investigators in the United States. Methods: A collaboration was established between investigators from several institutions in Vietnam and the University of Massachusetts Medical School that was built on mutual trust, cross-cultural learning, and shared experiences. This collaborative arrangement has led to sustainable stakeholder engagement in Vietnam. We formed a multidisciplinary transnational research team and maintained regular contact both online and in person. We also conducted a needs assessment study, in which several focus group discussions and in-depth interviews of stakeholders in Vietnam were carried out. Results: The formal collaboration between investigators in Vietnam and the University of Massachusetts Medical School began in 2011 and has strengthened over time. The U.S. team provided expertise in study and intervention design, data collection and analysis, and trial implementation, whereas the team in Vietnam brought a deep understanding of local health care delivery systems and expertise in the delivery of health care interventions at the grassroots level. Our initial partnership has now grown to include committed individuals at the government, academic, and community levels including the Vietnam Ministry of Health, key governmental and nongovernmental research institutions and agencies, medical and public health universities, and communities in rural settings. The needs assessment study found that there are important gaps in the delivery of hypertension management practices in many rural communities in Vietnam and that stakeholders are fully engaged in our ongoing, community-based, hypertension-control project. Conclusions: Multiple layers of stakeholders and communities in Vietnam are fully engaged with, and have contributed significantly to, our ongoing hypertension control research project in Northern Vietnam. © 2019 World Heart Federation (Geneva). **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Huy Nguyen” is provided in this record*

Single phase second order sliding mode controller for complex interconnected systems with extended disturbances and unknown time-varying delays

Novel results on complex interconnected time-delay systems with single phase second order sliding mode control is investigated. First, a reaching phase in traditional sliding mode control (TSMC) is removed by using a novel single phase switching manifold function. Next, a novel reduced order sliding mode observer (ROSMO) with lower dimension is suggested to estimate the unmeasurable variables of the plant. Then, a new single phase second order sliding mode controller (SPSOSMC) is established based on ROSMO tool to drive the state variables into the specified switching manifold from beginning of the motion and reduce the chattering in control input. Then, a stability condition is suggested based on the well-known linear matrix inequality (LMI) method to ensure the asymptotical stability of the whole plant. Finally, an illustrated example is simulated to validate the feasible application of the suggested technique

DoubleEcho: Mitigating Context-Manipulation Attacks in Copresence Verification

Copresence verification based on context can improve usability and strengthen security of many authentication and access control systems. By sensing and comparing their surroundings, two or more devices can tell whether they are copresent and use this information to make access control decisions. To the best of our knowledge, all context-based copresence verification mechanisms to date are susceptible to context-manipulation attacks. In such attacks, a distributed adversary replicates the same context at the (different) locations of the victim devices, and induces them to believe that they are copresent. In this paper we propose DoubleEcho, a context-based copresence verification technique that leverages acoustic Room Impulse Response (RIR) to mitigate context-manipulation attacks. In DoubleEcho, one device emits a wide-band audible chirp and all participating devices record reflections of the chirp from the surrounding environment. Since RIR is, by its very nature, dependent on the physical surroundings, it constitutes a unique location signature that is hard for an adversary to replicate. We evaluate DoubleEcho by collecting RIR data with various mobile devices and in a range of different locations. We show that DoubleEcho mitigates context-manipulation attacks whereas all other approaches to date are entirely vulnerable to such attacks. DoubleEcho detects copresence (or lack thereof) in roughly 2 seconds and works on commodity devices

Effect of chromium substituted on structural and magnetic characterization lithium ferrite nanoparticles

In this work, we present a structural, morphology and magnetic study of the Li0.5Fe2.5-xCrxO4 spinel nanoparticles (x = 0, 0.5, 0.75, 1, and 1.25) with mean particle size of 20-30 nm prepared by sol-gel method. The lattice constants and the size of particle decrease with increasing Cr concentration. In these samples, the preference of Cr3+ and Li+ ions in the octahedral sites and a small degree of site-interchange between Li+ in the octahedral sites and Fe3+ in the tetrahedral sites were found which increases with increasing the Cr content. A decrease of magnetization due to the spin disorder in the surface layer of the particles was observed. The spontaneous magnetization at 5K suggests the Néel type of magnetic ordering in these samples. The magnetic coercivity is discussed in terms of particle size, morphology and chromium substitution. Keywords. Chromium substitution, sol-gel method, nanoparticles, lithium ferrite

On Graphs with Finite-Time Consensus and Their Use in Gradient Tracking

This paper studies sequences of graphs satisfying the finite-time consensus property (i.e., iterating through such a finite sequence is equivalent to performing global or exact averaging) and their use in Gradient Tracking. We provide an explicit weight matrix representation of the studied sequences and prove their finite-time consensus property. Moreover, we incorporate the studied finite-time consensus topologies into Gradient Tracking and present a new algorithmic scheme called Gradient Tracking for Finite-Time Consensus Topologies (GT-FT). We analyze the new scheme for nonconvex problems with stochastic gradient estimates. Our analysis shows that the convergence rate of GT-FT does not depend on the heterogeneity of the agents' functions or the connectivity of any individual graph in the topology sequence. Furthermore, owing to the sparsity of the graphs, GT-FT requires lower communication costs than Gradient Tracking using the static counterpart of the topology sequence