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Integrating a vapor ejector with an air-cooled absorption cooling system (ACS) requires understanding how the ejector responds to varying condenser conditions and how the geometrical parameters affect the system's performance. This study provides a numerical investigation of the flow characteristics inside supersonic vapor ejectors. The primary objectives were identifying the best nozzle design for ACS and explaining how the secondary flow responds to different back pressures. The developed model was validated against experimental data and a one-dimensional model. Despite exhibiting increased flow fluctuations, the convex nozzle achieved an entrainment ratio of 0.4. This value was 4.9 % and 7 % higher than the values obtained by the straight and the concave nozzles, respectively. In contrast, the concave nozzle exhibits better flow stability and pressure recovery, which are considered appealing for the air-cooled ACS. The straight nozzle emerged as a balanced alternative, offering moderate entrainment alongside favorable flow stability. Moreover, secondary flow behavior at different operating modes was elaborated. Secondary flow choked at back pressures between 60–70 kPa, indicating optimal entrainment. However, at 75–80 kPa, while the secondary flow was entrained, it failed to reach sonic speed due to high-pressure waves, resulting in the sub-critical condition. Further increases in back pressure to 85–90 kPa induced back-flow due to elevated local static pressure. Mach number profiles at the mixing tube entrance remained consistent under critical operation but deviated post-critical back pressure, reflecting altered flow characteristics downstream of the mixing tube. Such elaboration of flow dynamics within ejectors paves the way for innovative designs of vapor ejectors, potentially developing ACS.

Abstract Background The COVID-19 pandemic and the consequences of safety measures, such as lockdowns, have impacted not only the physical health of individuals but also their lifestyle, psychosocial health, and mental health. In this analysis, we aimed to explore the effect of the COVID-19 pandemic on lifestyle, eating habits, and sleep quality in the Palestinian population. Furthermore, the current study aimed to determine the factors associated with poor sleep. Methods The study was carried out between November 2021 and February 2022 after a long lockdown. We adopted a cross-sectional design to achieve the objectives of this study. The questionnaire included information on sociodemographic characteristics and other characteristics. In addition, questions related to lifestyle changes and items related to changes in the consumption of certain types of food were included. Furthermore, in the present study, two scales were used to assess sleep quality: the Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI). Results A total of 978 participants were included in this study; 508 (51.9%) were women, and 465 (47.5%) were aged between 17 and 30 years. 41% of the participants added one meal or more, and almost 43% skipped one meal or more. A total of 39.2% believed that their habits worsened as a result of the COVID-19 pandemic. A significant portion of the population increased their vitamin intake by 62.5%. In general, nuts, fast food, fried food, coffee, snacks, cans, and homemade baked foods were consumed at higher rates overall. The median ESS score, which measures general levels of daytime drowsiness, was 20.00 (18.00–22.00). Residency (p = 0.008), living status (p

High-resolution remote sensing platforms are crucial to map land use/cover (LULC) types. Unmanned aerial vehicle (UAV) technology has been widely used in the northern hemisphere, addressing the challenges facing low- to medium-resolution satellite platforms. This study establishes the scalability of Sentinel-2 LULC classification with ground-linked UAV orthoimages to large African ecosystems, particularly the Burunge Wildlife Management Area in Tanzania. It involved UAV flights in 19 ground-surveyed plots followed by upscaling orthoimages to a 10 m × 10 m resolution to guide Sentinel-2 LULC classification. The results were compared with unguided Sentinel-2 using the best classifier (random forest, RFC) compared to support vector machines (SVMs) and maximum likelihood classification (MLC). The guided classification approach, with an overall accuracy (OA) of 94% and a kappa coefficient (k) of 0.92, outperformed the unguided classification approach (OA = 90%; k = 0.87). It registered grasslands (55.2%) as a major vegetated class, followed by woodlands (7.6%) and shrublands (4.7%). The unguided approach registered grasslands (43.3%), followed by shrublands (27.4%) and woodlands (1.7%). Powerful ground-linked UAV-based training samples and RFC improved the performance. The area size, heterogeneity, pre-UAV flight ground data, and UAV-based woody plant encroachment detection contribute to the study’s novelty. The findings are useful in conservation planning and rangelands management. Thus, they are recommended for similar conservation areas.

Elastic deformation of soft substrates occurs upon wetting, yet it is challenging to follow its dynamics at a microscale. Khattak et al. show that the force required to pull a droplet along a soft surface decreases monotonically as the film thickness decreases and explain the phenomenon using a scaling analysis.

Absorption cooling systems (ACS) have lower coefficients of performance (COP) compared to direct expansion (DX) cooling systems. Nevertheless, ACS offers a green alternative to typical DX systems. In this study, a numerical model was developed for the commercial low-capacity Robur® absorption cooling system (RACS). The model was developed based on mass, concentration, and energy balance equations, in addition to heat transfer equations. The model results were validated against experimental data available in the literature for the same cooling unit yielding a good agreement. Hence, to improve the COP of the RACS, a vapor ejector was introduced between the generator and the condenser. An improvement of 70.6% in the COP was obtained at the design condition. A parametric analysis was implemented to study the significance of the key parameters in the RACS performance. It was found that the increase in the ambient temperature not only increased the activation temperature, but it also decreased the COP and increased the circulation ratio (CR). Consequently, in hot environments, lowering the evaporator temperature is recommended to avoid the need for higher CR. Optimizing the nozzle throat and the mixing tube diameter improves the ejector performance, and hence the RACS performance, as long as the ejector operates under critical conditions. Finally, the absorber coil was found to have the most significance on the RACS performance in comparison with the rectifier coil and the refrigerant heat exchanger.

Habitat condition is a vital ecological attribute in wildlife conservation and management in protected areas, including the Burunge wildlife management areas in Tanzania. Traditional techniques, including satellite remote sensing and ground-based techniques used to assess habitat condition, have limitations in terms of costs and low resolution of satellite platforms. The Normalized Difference Vegetation Index (NDVI) and Green NDVI (GNDVI) have potential for assessing habitat condition, e.g., forage quantity and quality, vegetation cover and degradation, soil erosion and salinization, fire, and pollution of vegetation cover. We, therefore, examined how the recently emerged Unmanned Aerial Vehicle (UAV) platform and the traditional Sentinel-2 differs in indications of habitat condition using NDVI and GNDVI. We assigned 13 survey plots to random locations in the major land cover types: three survey plots in grasslands, shrublands, and woodlands, and two in riverine and mosaics cover types. We used a UAV-mounted, multi-spectral sensor and obtained Sentinel-2 imagery between February and March 2020. We categorized NDVI and GNDVI values into habitat condition classes (very good, good, poor, and very poor). We analyzed data using descriptive statistics and linear regression model in R-software. The results revealed higher sensitivity and ability of UAV to provide the necessary preliminary diagnostic indications of habitat condition. The UAV-based NDVI and GNDVI maps showed more details of all classes of habitat conditions than the Sentinel-2 maps. The linear regressions results showed strong positive correlations between the two platforms (p < 0.001). The differences were attributed primarily to spatial resolution and minor atmospheric effects. We recommend further studies to test other vegetation indices.

Imtinene Ben Mrad,1 Ramy Ben Salah,2 Melek Ben Mrad,3 Rim Miri,3 Anis Haddad,4 Sobhi Mleyhi,3 Ihsen Zairi,1 Khalil Hamza,5 Mariem Jrad,5 Raouf Denguir3 1Cardiology Department, Hbib Thameur Hospital, Tunis, Tunisia; 2Plastic Surgery Department, Bizerte Hospital, Tunis, Tunisia; 3Cardiovascular Surgery Department, Rabta Hospital, Tunis, Tunisia; 4General Surgery Department, Rabta Hospital, Tunis, Tunisia; 5Radiology Department, Charles Nicolle Hospital, Tunis, TunisiaCorrespondence: Melek Ben MradCardiovascular Surgery Department, Rabta Hospital, App 2b, Bloc 12, Cite Olympique, Tunis 1003, TunisiaTel +21655657116Email benmradmelek@yahoo.frAbstract: Aneurysms and pseudoaneurysms of the gluteal artery are rare. They represent less than 1% of the described arterial aneurysms. Those that touch the inferior gluteal artery are even rarer. Only a few cases have been described worldwide. Such cases often present with a variable time course, mode of injury, and associated symptoms, leading to their misdiagnosis and improper treatment. We present the case of a 30-year-old male, who presented to our emergency room one week after a stab wound in the left gluteal region causing a pseudoaneurysm of the left inferior gluteal artery with a sciatic compartment syndrome treated by a hybrid approach.Keywords: pseudoaneurysm, inferior gluteal artery, stab wound, embolization, sciatic nerve

High-resolution remote sensing platforms are crucial to map land use/cover (LULC) types. Unmanned aerial vehicle (UAV) technology has been widely used in the northern hemisphere, addressing the challenges facing low- to medium-resolution satellite platforms. This study establishes the scalability of Sentinel-2 LULC classification with ground-linked UAV orthoimages to large African ecosystems, particularly the Burunge Wildlife Management Area in Tanzania. It involved UAV flights in 19 ground-surveyed plots followed by upscaling orthoimages to a 10 m × 10 m resolution to guide Sentinel-2 LULC classification. The results were compared with unguided Sentinel-2 using the best classifier (random forest, RFC) compared to support vector machines (SVMs) and maximum likelihood classification (MLC). The guided classification approach, with an overall accuracy (OA) of 94% and a kappa coefficient (k) of 0.92, outperformed the unguided classification approach (OA = 90%; k = 0.87). It registered grasslands (55.2%) as a major vegetated class, followed by woodlands (7.6%) and shrublands (4.7%). The unguided approach registered grasslands (43.3%), followed by shrublands (27.4%) and woodlands (1.7%). Powerful ground-linked UAV-based training samples and RFC improved the performance. The area size, heterogeneity, pre-UAV flight ground data, and UAV-based woody plant encroachment detection contribute to the study's novelty. The findings are useful in conservation planning and rangelands management. Thus, they are recommended for similar conservation areas. [ABSTRACT FROM AUTHOR]

Vaginal discharge in women is occasionally caused by aerobic bacterial organisms. The study aimed to determine the etiology of female vaginosis and their antibiotic sensitivity pattern. HV culture results, age, and sex of all female patients with suspected bacterial vaginosis were collected. High vaginal swabs were inoculated into MacConkey agar, 5% blood agar, and chocolate agar and then incubated at 37°C in the presence of 5% CO2 for 24-48 h. The antimicrobial susceptibility testing was performed by the disk diffusion method. Ten different antibiotic discs were used: Amikacin, Augmentin, Ceftazidime, Ceftriaxone, Ciprofloxacin, Gentamicin, Levofloxacin, Meropenem, Septrin, and Clindamycin. After 24 hours, zones were measured in mm, and zone interpretations were in accordance with the National Committee for Clinical Laboratory Standards criteria guidelines. A total of 215 females were included in the study, the incidence of bacterial vaginosis was 18.6% (40/215). Females between 33 and 45 years old had a somewhat high prevalence (19/40:47.5%) of bacterial vaginosis. The most frequent isolates were 45% (18/40) Escherichia coli followed by 15% (6/40) Strep pneumonia. The in vitro susceptibility tests of the most common isolates showed high resistance levels to commonly used antibiotics such as Augmentin and Gentamycin. Whereas highly sensitive rates were observed for Ceftriaxone 70%, followed by Ciprofloxacin 57.5%. Ceftriaxone and Ciprofloxacin showed the best antibiotic sensitivity. Additional studies are necessary to recognize those bacterial species that cause vaginal infections and determine the susceptibility of those species to recently used antibiotics.

Obstructive sleep apnea (OSA) is highly prevalent in individuals with Down syndrome (DS), affecting more than 50% of this population during childhood and reaching up to 100% in adulthood. This disorder poses significant clinical consequences, including impaired cognitive function, developmental delay, and cardiovascular complications. To address this, direct hypoglossal nerve stimulation (HNS) has been approved as a treatment modality for OSA. Recent studies have shown a significant positive correlation between HNS voltage and post-apnea-hypopnea index (AHI) levels in DS and non-DS patients. However, concerns regarding the reliability of some findings have been raised, emphasizing the need for further research to underline the usefulness of HNS in treating OSA in DS patients. This meta-analysis provides a comprehensive review and analysis of the available case reports, case series, and cohort studies to evaluate the safety and efficacy of HNS in treating OSA in Down syndrome patients. [ABSTRACT FROM AUTHOR]

Objectives: This study concentrated on determining the total hydrocarbon concentrations in soil at eleven stations of the oil field (Seba, Safwan, Majnoon, Ratawi, Bergezia, Qurna2, Qurna1, Shuaaba, South and North Rumaila, and Al Zubair). Methods: Soil samples were freeze-dried, finely pulverised in an agate mortar, and sieved through a 62-um metal sieve and 150 ml mixture of methanol and benzene (1:1) was used to extract the soil. Determination of TPHs where determined by using Spectrofluroscence, Total organic carbons (TOC) in the soil of the oil fields were also determined. Results: According to the TPH distribution used in this investigation, station 11 (Al Zubair) had the highest concentration of TPHs (162.53μg/g dry weight), while station 1(Seba) had the lowest concentration (21.4μg/g dry weigh). Additionally, the study's findings demonstrated that TPH levels varied spatially amongst sites. The highest amounts of total petroleum hydrocarbons detected in soil samples, as well as the findings of this investigation indicating that TPH levels varied geographically throughout stations. Conclusions: There is significant correlation between the TPH in soil and TOC%. By comprising the result concentration of this study with literature reviews, the concentration levels lies within it and in other cases exceed it. [ABSTRACT FROM AUTHOR]

Absorption Refrigeration Systems (ARS) are potential alternatives to direct expansion (DX) refrigeration systems. This review focused on the incorporation of an ejector into absorption refrigeration cycles to constitute Hybrid Ejector-Absorption Refrigeration Systems (HEARS). The ejector adds several advantages to the absorption refrigeration systems depending on its location in the cycle. The two prevalent configurations of HEARS are Triple pressure level (TPL-HEARS), and Low Pressure Condenser (LPC-HEARS). Previous studies revealed the preference of the latter configuration as it allows lower circulation ratios, enhances the refrigeration effect, and could achieve a COP up to 1. Moreover, LPC configuration is suitable with single, double, and variable-effect absorption systems with a COP of above unity. In turn, the TPL-HEARS notably enhances the absorption process, particularly when a variable geometry ejector is utilized. This configuration could obtain a COP around 1.1, but only with high-density refrigerant vapor. Lately, to attain the advantages of both configurations, some studies investigated the viability of adding two ejectors to the cycle. This paper meticulously reviews investigations conducted on the emerging dual ejectors-absorption refrigeration technology. This paper reveals the general performance trend and the maximum attainable COP by each type of hybrid ejector-absorption refrigeration system. DEARS and Ejector-driven absorption refrigeration systems (ED-ARS) could achieve COP that ranges between 1.2 and 1.46. The use of a flash tank and a RHE is essential in NH3/H2O HEARS. At high generator temperatures (of 120–170 °C), DEARS was found to be the system with less complexity and best performance. Nevertheless, the performance of the DEARS might drop significantly if the heat source temperature is fluctuating. Thence, the variable-effect HEARS is considered the best alternative. The capability of HEARS to be integrated with different power generation cycles is also highlighted. Finally, the review presents possible future research opportunities to improve the absorption refrigeration technology.