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Ship detection in synthetic aperture radar (SAR) images is widely applied in marine monitoring. In recent years, convolutional neural networks (CNNs) have made significant advances in SAR ship detection. However, the scene imbalance problem, i.e. much more offshore scenes than inshore scenes in SAR images, severely hampers the improvement of detection accuracy. In this article, we propose scene-aware data augmentation to address the problem. First, a novel concept, inshore rate, is introduced to estimate the land area percentage of various scenes in SAR images. We can divide image samples into inshore and offshore ones based on the inshore rate without manual category annotations. Second, to augment inshore samples, we synthesize dummy inshore images by cropping the ground truth bounding boxes (GT bboxes) from offshore images and pasting them onto inshore images. This offline data augmentation strategy can address the scene imbalance problem and improve detection accuracy. The experiments conducted on SAR Ship Detection Dataset (SSDD) and Large-Scale SAR Ship Detection Dataset (LS-SSDD) demonstrate the effectiveness of the proposed method in improving detection performance. [ABSTRACT FROM AUTHOR]

A new benzofuran derivative, identified as myrrhain A (1), was isolated from the resinous exudates of Commiphora myrrha, together with the four known compounds: commipharane (2), myrrhterpeniod (3), myrrhone (4), and 9-methoxymyrrhone (5). All structures were elucidated by NMR and MS analyses. DPPH assay of compounds 1–5 revealed for the first time that all of them possess moderate antioxidative activity. [ABSTRACT FROM AUTHOR]

In this study, we aimed to examine the effectiveness of augmented reality (AR)-assisted technology in laparoscopic partial nephrectomy (LPN) compared to conventional technique. We performed a systematic search through the Cochrane Library, PubMed, Embase, Web of Science, ScienceDirect, and Wanfang for eligible studies published up to 30 September 2021. The literature quality was independently evaluated by two investigators, and all statistical analysis was performed using STATA version 12.0 (STATA Corporation, Houston, TX, USA). According to the different surgical techniques and surgical risks, the included articles were divided into two subgroups. The reviewed studies included five retrospective comparative studies (RCS), two prospective controlled studies (PCS), one randomized controlled trial (RCT) including 548 patients. The AR-assisted LPN had following distinctive advantages compared to conventional nephrectomy: shorter procedure times and lower intraoperative blood loss. Additionally, there was no statistically significant difference in margin-positive resection rate, warm ischemia time, complications, eGFR decline and length of stay between these two technologies. Compared to the conventional technique, AR-assisted LPN appears to be a preferable treatment. However, a high degree of statistical heterogeneity was observed in the meta-analysis. Well-designed prospective trials and large-scale RCTs are needed to draw definitive findings from this analysis. [ABSTRACT FROM AUTHOR]

Cognitive frailty, a potentially reversible condition describing the concurrence of physical frailty and mild cognitive impairment (MCI), has been recently proposed to incorporate subjective cognitive decline (SCD), a reversible pre-MCI state with more readily available cognitive reserve, as well as pre-physical frailty. Reversible cognitive frailty has been associated with dementia and mortality. We aimed to examine the association of reversible cognitive frailty with other adverse outcomes including disability, poor quality of life (QOL), depression, and hospitalization. This was a cohort study with 1-year follow-up among 735 Chinese community-dwelling older adults with intact cognition. Reversible cognitive frailty was operationalized with the presence of pre-physical or physical frailty identified by the Frailty Phenotype and SCD identified by the simplified SCD questionnaire including four self-report cognitive domains of memory, naming, orientation, and mathematical reasoning. Adverse outcomes included incident Activities of Daily Living (ADL)-Instrumental ADL (IADL) disability, poor physical, mental and overall QOL, depression, and hospitalization over 1-year follow-up. The prevalence of reversible cognitive frailty was 27.8%. Participants with reversible cognitive frailty had higher risk of the incidence of ADL-IADL disability, poor physical QOL, poor mental QOL, poor overall QOL, and depression (Odds Ratios: 1.67–4.38, P < 0.05), but not higher risk of hospitalization over 1-year follow-up. Reversible cognitive frailty was not uncommon and associated with incident disability, poor QOL, and depression among community-dwelling older adults. Early identification of reversible cognitive frailty can facilitate targeted interventions and may promote independence in older adults. Supplemental data for this article is available online at http://dx.doi.org/10.1080/13607863.2021.2011835 [ABSTRACT FROM AUTHOR]

Remdesivir is one of the effective drugs proposed for the treatment of coronavirus disease 2019 (COVID-19). However, the study on inhalable regimen is currently limited though COVID-19 is respiratory diseases and infects lung area. This work aims to prepare inhalable remdesivir formulations and verify their effectiveness through in vitro evaluations. Formulations containing different ratios of jet-milled inhalable remdesivir (5, 10, 20,40, and 70%) with excipients were produced and characterized in terms of the particle size distribution, particle morphology, flowability, water content, crystallinity, the water sorption and desorption capabilities, and the aerodynamic performance. Results indicating that drug loading are a vital factor in facilitating the dispersion of remdesivir dry powder, and the ternary excipient plays a negligible role in improving aerosol performance. Besides, the 70% remdesivir with lactose carrier (70% RD-Lac) was physically stable and retain high aerosol performance after conditioned at 40 °C and 75% RH for a month. Therefore, formulation 70% RD-Lac might be recommended as a candidate product for the potential treatment of COVID-19. [ABSTRACT FROM AUTHOR]

To reveal the formation mechanism of a pulse-jet airflow’s cleaning effect in a filter bag, a theoretical model is built by using the theory of the gas jet and unitary adiabatic flow according to given specifications and dimensions of the bags and resistance characteristics of the cloth and dust layer. It is about the relationship between cleaning system structure and operating parameters. The model follows the principle that the flow and kinetic energy of jet flow injected into a filter bag should be consistent with the flow of cleaning airflow in the bag and the pressure drop flowing through the filter cloth and dust layer. The purpose of the model is to achieve the peak pressure of cleaning airflow, which dominates the effect of the pulse-jet cleaning process. The cleaning system structure includes air pressure in the nozzle, structure and size of nozzle, exit velocity of nozzle, jet distance, and diameter of jet cross section. Based on the condition of the cleaning system structure and operating parameters established by using the theoretical model, Fluent software is applied to carry out a numerical simulation of the jet airflow field at the nozzle’s outlet, jet airflow field between nozzle and bag top, and cleaning airflow field in the filter bag. Experimental results are used to verify the reliability of the theoretical model. They are obtained in a pilot-scale test filter with a single bag, with length 2 m and in general full-scale dimensions of the cleaning system. The results show that when any rectification measure is not installed at the bag opening, the cross-sectional area covered by the jet gas is hardly sufficient to cover the entire area of the bag opening. A large portion of the gases injected into the filter bag will overflow reversely upward from the edge due to pressure differences between the upper area and lower area inside the bag opening. This led to a serious shortage of the cleaning airflow and ar limited increase in static pressure. When a venturi-type rectifier tube is installed at the bag opening, the jet flow is converted to funnel flow for which the cross-section velocity distribution is more uniform at the throat of the rectifier tube due to the guided effects of the upper tapered pipe. Then it is transited to stressful flow below the bag opening via rectified effects of the lower dilated pipe. The results show that the gap between the static pressure of gas in the bag and the expected value is significantly reduced. The theoretical value of the nozzle diameter is enlarged to compensate for two aspects of adverse effects of cleaning airflow and energy. This is because the flow is not a purely free-form jet from the nozzle to the entrance of the rectifier tube and because the gas suffers from local resistance while flowing through the rectifier tube. The numerical simulation and experiment show that the peak pressure of cleaning airflow in the filter bag is able to reach the expected value. The results confirm that the mechanism of the pulse-jet cleaning airflow and the calculation method of the pulse-jet cleaning system structure and operating parameters offered in this study are correct. The study results provide a scientific basis for designing the system of pulse-jet fabric filters. Implications: Pulse-jet cleaned fabric filters are commonly used for air pollution control in many industries. Pulse-jet cleaning is widely used for this purpose as it enables frequent cleaning while the filter is operating. However, the theoretical system of the forming mechanism of the pulse-jet cleaning has not formed so far. This indicates the theoretical model plays an important role in designing effective pulse-jet cleaned fabric filters. [ABSTRACT FROM PUBLISHER]