84 research outputs found
A New Hybrid Model Based on an Intelligent Optimization Algorithm and a Data Denoising Method to Make Wind Speed Predication
To mitigate the increase of anxiety resulting from the depletion of fossil fuels and destruction of the ecosystem, wind power, as the most common renewable energy, is a flourishing industry. Thus, accurate wind speed forecasting is critical for the efficient function of wind farms. However, affected by complicated influence factors in meteorology and volatile physical property, wind speed forecasting is difficult and challenging. Based on previous research efforts, an intelligent hybrid model was proposed in this paper in an attempt to tackle this difficult task. First, wavelet transform was utilized to extract the main components of the original wind speed data while eliminating noise. To make better use of the back-propagation artificial neural network, the initial parameters of the network are substituted with optimized ones, which are achieved by using the artificial fish swarm algorithm (AFSA), and the final combination model is employed to conduct wind speed forecasting. A series of data are collected from four different observation sites to test the validity of the proposed model. Through comprehensive comparison with the traditional models, the experiment results clearly indicate that the proposed hybrid model outperforms the traditional single models
Repellency Assessment of Nepeta cataria Essential Oils and Isolated Nepetalactones on Aedes aegypti.
There is an increased need for improved and affordable insect repellents to reduce transmission of rapidly spreading diseases with high mortality rates. Natural products are often used when DEET cannot be afforded or accessed and when consumers choose not to use a synthetic repellent. The essential oils from two newly bred Nepeta cataria (catnip) plants representing two different chemotypes and their respective isolated nepetalactone isomers were evaluated as mosquito repellents against Aedes aegypti mosquitoes that transmit the Zika and Dengue virus in a one choice landing rate inhibition assay. A dose response curve was generated for each treatment and a time course analysis of repellency was performed over 24 hours with a N. cataria essential oil sample. The results indicate that all essential oil samples and their respective purified nepetalactone isomers were able to achieve greater than 95% repellency. Between two and four hours, the ability to repel more than 95% of the mosquitoes diminished. At the lowest concentrations tested, the nepetalactones and crude essential oil samples were more effective than DEET at reducing the number of mosquito landings
Quantitative risk assessment of non-typhoidal Salmonella enterica in pork products
Non-typhoidal Salmonella enterica is one of most important foodborne pathogens in the world. It infects humans through contaminated poultry and livestock meats. Published literature were reviewed to better understand quantitative microbiological risk assessment (QMRA) of non-typhoidal Salmonella enterica in pork products, especially the models commonly used. The challenges of QMRA of non-typhoidal Salmonella enterica in pork in China were analyzed, which could be the reference for the researches to be conducted in the future
EDMAE: An Efficient Decoupled Masked Autoencoder for Standard View Identification in Pediatric Echocardiography
This paper introduces the Efficient Decoupled Masked Autoencoder (EDMAE), a
novel self-supervised method for recognizing standard views in pediatric
echocardiography. EDMAE introduces a new proxy task based on the
encoder-decoder structure. The EDMAE encoder is composed of a teacher and a
student encoder. The teacher encoder extracts the potential representation of
the masked image blocks, while the student encoder extracts the potential
representation of the visible image blocks. The loss is calculated between the
feature maps output by the two encoders to ensure consistency in the latent
representations they extract. EDMAE uses pure convolution operations instead of
the ViT structure in the MAE encoder. This improves training efficiency and
convergence speed. EDMAE is pre-trained on a large-scale private dataset of
pediatric echocardiography using self-supervised learning, and then fine-tuned
for standard view recognition. The proposed method achieves high classification
accuracy in 27 standard views of pediatric echocardiography. To further verify
the effectiveness of the proposed method, the authors perform another
downstream task of cardiac ultrasound segmentation on the public dataset CAMUS.
The experimental results demonstrate that the proposed method outperforms some
popular supervised and recent self-supervised methods, and is more competitive
on different downstream tasks.Comment: 15 pages, 5 figures, 8 tables, Published in Biomedical Signal
Processing and Contro
Research Progress on Survival Mechanism and Control Measures of Salmonella enterica Serovar Enteritidis in Egg White
Salmonella is one of the most common pathogens causing foodborne diseases. Eggs and egg products are important food vehicles for its transmission. Among the many serotypes of Salmonella, S. enterica serovar Enteritidis has a unique advantage in surviving egg white because of its resist to antibacterial molecules in egg white, which can lead to food poisoning. In recent years, the survival strategies of S. enteritidis serovar Enteritidis in egg white have been explored by using molecular biological techniques such as transposon mutations, in vivo expression, high-throughput sequencing and omics, and some key metabolic pathways and stress resistance-related genes/proteins have been discovered. However, the function of stress resistance-related genes has not been fully revealed, and there is a lack of a comprehensive summary of the existing research. Therefore, the current situation and transmission routes of Salmonella contaminated eggs are briefly introduced in this review. Furthermore, the latest progress in research on the survival mechanism of S. enteritidis serovar Enteritidis in egg white is summarized from the perspectives of nutrient availability, membrane stress response, deoxyribonucleic acid (DNA) damage repair, alkaline pH adaptation, osmotic stress response and energy metabolism. Finally, the biological control methods for Salmonella are summarized, including vaccines, bacteriophages, and probiotics. Meanwhile, future research directions are discussed. This article will provide an important reference for effective control of Salmonella in eggs and egg products
Paeoniflorin Attenuated Oxidative Stress in Rat COPD Model Induced by Cigarette Smoke
Paeoniflorin (PF), a monoterpene glucoside, might have an effect on the oxidative stress. However, the mechanism is still unknown. In this study, we made the COPD model in Sprague-Dawley (SD) rats by exposing them to the smoke of 20 cigarettes for 1 hour/day and 6 days/week, for 12 weeks, 24 weeks, or 36 weeks. Our findings suggested that smoke inhalation can trigger the oxidative stress from the very beginning. A 24-week treatment of PF especially in the dosage of 40 mg/kg·d can attenuate oxygen stress by partially quenching reactive oxygen species (ROS) and upregulating antioxidant enzymes via an Nrf2-dependent mechanism
Low temperature and temperature decline increase acute aortic dissection risk and burden: A nationwide case crossover analysis at hourly level among 40,270 patients.
Background: Acute aortic dissection (AAD) is a life-threatening cardiovascular emergency with high mortality, so identifying modifiable risk factors of AAD is of great public health significance. The associations of non-optimal temperature and temperature variability with AAD onset and the disease burden have not been fully understood. Methods: We conducted a time-stratified case-crossover study using a nationwide registry dataset from 1,868 hospitals in 313 Chinese cities. Conditional logistic regression and distributed lag models were used to investigate associations of temperature and temperature changes between neighboring days (TCN) with the hourly AAD onset and calculate the attributable fractions. We also evaluated the heterogeneity of the associations. Findings: A total of 40,270 eligible AAD cases were included. The exposure-response curves for temperature and TCN with AAD onset risk were both inverse and approximately linear. The risks were present on the concurrent hour (for temperature) or day (for TCN) and lasted for almost 1 day. The cumulative relative risks of AAD were 1.027 and 1.026 per 1°C lower temperature and temperature decline between neighboring days, respectively. The associations were significant during the non-heating period, but were not present during the heating period in cities with central heating. 23.13% of AAD cases nationwide were attributable to low temperature and 1.58% were attributable to temperature decline from the previous day. Interpretation: This is the largest nationwide study demonstrating robust associations of low temperature and temperature decline with AAD onset. We, for the first time, calculated the corresponding disease burden and further showed that central heating may be a modifier for temperature-related AAD risk and burden. Funding: This work was supported by the National Natural Science Foundation of China (92043301 and 92143301), Shanghai International Science and Technology Partnership Project (No. 21230780200), the Medical Research Council-UK (MR/R013349/1), and the Natural Environment Research Council UK (NE/R009384/1)
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Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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