15 research outputs found
Design and simulation of automotive radar for autonomous vehicles
Modern automobile technology is pushing towards maximizing road safety, connected vehicles, autonomous vehicles, etc. Automotive RADAR is core sensor technology used for ADAS (Advanced Driver Assistance Technology), ACC (Adaptive Cruise Control), AEB (Automatic Emergency Braking System), traffic assistance, parking aid, and obstacle/pedestrian detection. Despite being inexpensive, RADAR technology provides robust results in harsh conditions such as harsh weather, extreme temperature, darkness, etc. However, the performance of these systems depends on the position of the RADAR and its characteristics like frequency, beamwidth, and bandwidths. Moreover, the characterization of varied materials like layers of paint, polish, primer, or layer of rainwater needs to be analyzed. This performance can be predicted through real-time simulation using advanced FEM software like Altair FEKO&WinProp. These simulations can provide valuable insight into the performance of the system, allowing engineers to optimize the system for specific use cases. For example, simulation can be used to determine the optimal parameters of the RADAR system for a given application. This information can then be used to design and build a physical model or prototype that is optimized for the desired performance. These simulations play a prominent role in determining appropriate data collection and sensor fusion, which reduces the cost and time required for the development of a physical model or prototype. The continued growth and demand for advanced safety features in vehicles further highlight the importance of RADAR technology in modern automobile technology. By accurately characterizing the environment and simulating the system's behavior in real time, engineers can optimize RADAR systems for specific use cases, contributing to safer and more efficient driving experience
Functional redundancy of type I and type II receptors in the regulation of skeletal muscle growth by myostatin and activin A.
Myostatin (MSTN) is a transforming growth factor-β (TGF-β) family member that normally acts to limit muscle growth. The function of MSTN is partially redundant with that of another TGF-β family member, activin A. MSTN and activin A are capable of signaling through a complex of type II and type I receptors. Here, we investigated the roles of two type II receptors (ACVR2 and ACVR2B) and two type I receptors (ALK4 and ALK5) in the regulation of muscle mass by these ligands by genetically targeting these receptors either alone or in combination specifically in myofibers in mice. We show that targeting signaling in myofibers is sufficient to cause significant increases in muscle mass, showing that myofibers are the direct target for signaling by these ligands in the regulation of muscle growth. Moreover, we show that there is functional redundancy between the two type II receptors as well as between the two type I receptors and that all four type II/type I receptor combinations are utilized in vivo. Targeting signaling specifically in myofibers also led to reductions in overall body fat content and improved glucose metabolism in mice fed either regular chow or a high-fat diet, demonstrating that these metabolic effects are the result of enhanced muscling. We observed no effect, however, on either bone density or muscle regeneration in mice in which signaling was targeted in myofibers. The latter finding implies that MSTN likely signals to other cells, such as satellite cells, in addition to myofibers to regulate muscle homeostasis
Antibacterial activity of crude methanolic and fractionated extracts of Aaptos suberitoides
In this research, we at the first time assessed antibacterial effects of methanolic crude and fractionated extracts from the marine sponge, Aaptos suberitoides against three bacterial strains including E. coli., S. aureus, B. cereus. The anti-bacterial assays were carried out by the disc diffusion method to test the anti-bacterial activity of different concentrations of methanolic crude of A. suberitoides against the indicator bacterial pathogens. The results indicated that extracts of A. suberitoides exhibited anti-microbial activity against all tested bacterial strains in concentrationdependent manner. Moreover, we showed that the majority of the active compound was in the polar fractions
An Outbreak of Severe Infections with Community-Acquired MRSA Carrying the Panton-Valentine Leukocidin Following Vaccination
Background: Infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging
worldwide. We investigated an outbreak of severe CA-MRSA infections in children following out-patient vaccination.
Methods and Findings: We carried out a field investigation after adverse events following immunization (AEFI) were reported. We reviewed the clinical data from all cases. S. aureus recovered from skin infections and from nasal and throat swabs were analyzed by pulse-field gel electrophoresis, multi locus sequence typing, PCR and microarray. In May 2006, nine children presented with AEFI, ranging from fatal toxic shock syndrome, necrotizing soft tissue infection, purulent abscesses, to fever
with rash. All had received a vaccination injection in different health centres in one District of Ho Chi Minh City. Eight children had been vaccinated by the same health care worker (HCW). Deficiencies in vaccine quality, storage practices, or preparation and delivery were not found. Infection control practices were insufficient. CA-MRSA was cultured in four children and from nasal and throat swabs from the HCW. Strains from children and HCW were indistinguishable. All carried the Panton-Valentine leukocidine (PVL), the staphylococcal enterotoxin B gene, the gene complex for staphylococcal-cassette-chromosome mec type V, and were sequence type 59. Strain HCM3A is epidemiologically unrelated to a strain of ST59 prevalent in the USA, althoughthey belong to the same lineage.
Conclusions. We describe an outbreak of infections with CA-MRSA in children, transmitted by an asymptomatic colonized HCW during immunization injection. Consistent adherence to injection practice guidelines is needed to prevent CA-MRSA transmission in both in- and outpatient settings
Prospects for Food Fermentation in South-East Asia, Topics From the Tropical Fermentation and Biotechnology Network at the End of the AsiFood Erasmus+Project
Fermentation has been used for centuries to produce food in South-East Asia and some foods of this region are famous in the whole world. However, in the twenty first century, issues like food safety and quality must be addressed in a world changing from local business to globalization. In Western countries, the answer to these questions has been made through hygienisation, generalization of the use of starters, specialization of agriculture and use of long-distance transportation. This may have resulted in a loss in the taste and typicity of the products, in an extensive use of antibiotics and other chemicals and eventually, in a loss in the confidence of consumers to the products. The challenges awaiting fermentation in South-East Asia are thus to improve safety and quality in a sustainable system producing tasty and typical fermented products and valorising by-products. At the end of the “AsiFood Erasmus+ project” (www.asifood.org), the goal of this paper is to present and discuss these challenges as addressed by the Tropical Fermentation Network, a group of researchers from universities, research centers and companies in Asia and Europe. This paper presents current actions and prospects on hygienic, environmental, sensorial and nutritional qualities of traditional fermented food including screening of functional bacteria and starters, food safety strategies, research for new antimicrobial compounds, development of more sustainable fermentations and valorisation of by-products. A specificity of this network is also the multidisciplinary approach dealing with microbiology, food, chemical, sensorial, and genetic analyses, biotechnology, food supply chain, consumers and ethnology
Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial
Background
Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population.
Methods
AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921.
Findings
Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months.
Interpretation
Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke
Stock liquidity and capital structure: International evidence
Relying on the assumption that equity market provides useful information for firm decision, this study examines the effect of stock liquidity on corporate capital structure decision. We also analyze whether this effect varies according to country-level institutional environments. Using a comprehensive international dataset of 19,939 firms across 41 countries over 2000–2010, the paper offers two key findings. First, firms with higher stock market liquidity tend to have lower leverage. Second, countries with strong institutional environments are more likely to have a weaker (negative) relationship between stock market liquidity and leverage. These results are robust to different liquidity measurement and subsamples
Stock liquidity and capital structure: International evidence
Relying on the assumption that equity market provides useful information for firm decision, this study examines the effect of stock liquidity on corporate capital structure decision. We also analyze whether this effect varies according to country-level institutional environments. Using a comprehensive international dataset of 19,939 firms across 41 countries over 2000-2010, the paper offers two key findings. First, firms with higher stock market liquidity tend to have lower leverage. Second, countries with strong institutional environments are more likely to have a weaker (negative) relationship between stock market liquidity and leverage. These results are robust to different liquidity measurement and subsamples
Urban inundation forecasting based on hydraulic models coupling MIKE Flood and MIKE Urban: A case study of Tam Ky City, Vietnam
Abstract Urban inundation has become a growing concern for many coastal cities around the world. Tam Ky City, located downstream of Ban Thach and Tam Ky rivers in central Vietnam, is no exception. According to annual statistics, the city frequently experiences heavy rainfall from tropical storms and monsoons, making inundation a recurring issue. In response to this challenge, this study developed a flood forecasting model specifically tailored for Tam Ky City, based on forecast rainfall and tidal levels. A key strength of the flood forecasting model lies in its integration of rainfall‐runoff processes, effectively connecting the river basin and the city. To ensure the model's accuracy and reliability, the parameters of the flood forecasting model were meticulously calibrated and verified for floods occurred on rivers as well as in urban areas. An experimental flood forecast was performed during Typhoon Nuru on September 28, 2022, and the forecast results of inundation locations and depths in the city well reflected the actual observations
Diverse Characteristics of the cagA Gene of Helicobacter pylori Strains Collected from Patients from Southern Vietnam with Gastric Cancer and Peptic Ulcer▿
The pathogenesis of gastroduodenal diseases is related to the diversity of Helicobacter pylori strains. CagA-positive strains are more likely to cause gastric cancer than CagA-negative strains. Based on EPIYA (Glu-Pro-Ile-Tyr-Ala) motifs at the carboxyl terminus corresponding to phosphorylation sites, H. pylori CagA is divided into East Asian CagA and Western CagA. The former type prevails in East Asia and is more closely associated with gastric cancer. The present study used full sequences of the cagA gene and CagA protein of 22 H. pylori strains in gastric cancer and peptic ulcer patients from Southern Vietnam to make a comparison of genetic homology among Vietnamese strains and between them and other strains in East Asia. A phylogenetic tree was constructed based on full amino acid sequences of 22 Vietnamese strains in accordance with 54 references from around the world. The cagA gene was found in all Vietnamese H. pylori strains. Twenty-one of 22 (95.5%) strains belonged to the East Asian type and had similar characteristics of amino acid sequence at the carboxyl terminus to other strains from the East Asian region. From evidence of East Asian CagA and epidemiologic cancerous lesions in Vietnam, H. pylori-infected Vietnamese can be classified into a high-risk group for gastric cancer, but further studies on the interaction among environmental and virulence factors should be done. Finally, phylogenetic data support that there is a Japanese subtype in the Western CagA type