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Air plate solar collectors provide a sustainable and efficient solution for building heating. The absorber plate collects solar radiation and converts it into heat. Atmospheric air is then circulated through the collector plate with perforated baffles by forced convection. The heated air is then directed through ducts into the building’s heating system. By significantly reducing reliance on fossil fuels for building heating, these collectors contribute to a lower life-cycle carbon footprint for buildings compared to conventional heating systems. While flat-plate solar collectors are widely used for renewable energy generation, their efficiency is frequently limited by the airflow path and the heat transfer efficiency within the collector. This study aims to quantify the impact of longitudinal, transverse, and perforated baffles with different hole diameters on the heat transfer characteristics and to identify the optimal design for maximizing thermal efficiency. This study also aims to integrate solar air collector in a conventional building and help reduce the overall energy demand of buildings and their associated carbon emissions. A three-dimensional numerical investigation was carried out on a flat-plate solar collector equipped with perforated transverse baffles with varying hole diameter and thickness. The results from the study predicted that perforated baffles with two holes with a diameter of 15 mm provided a maximum Nu of 79.56 and a pressure drop of 459 Pa for a Re of 8500.

Algeria has paid attention to the higher education and scientific research sector through the five-year scientific research and technological development programs (1998-2002, 2008-2012, and 2014-2019). The study aims to evaluate the scientific research activities in Algerian universities within the framework of scientific research programs, to study the relationship of scientific activities by researchers in Algerian research laboratories with Webometrics ranking of Algerian universities. It is eluted what are the scientific activities of Algerian researchers which have the most impact on the ranking of Algerian universities in the Webometrics ranking. We adopted the experimental, exploratory approach by collecting, exploring, and analyzing the correlation between of data from the Algerian university rankings according to the number of researchers in the research laboratories, the number of citations, the number of patents, published papers, and the ranking of each Algerian university in Webometrics ranking, by Spearman’s correlation coefficient to test the strength and signification of the correlation between these rankings. The results showed development in the various components of scientific, material, human and financial research, but it is not enough. Also, despite many research laboratories, researchers at these laboratories, and the improvement in the number of internationally published research in each Algerian university, this did not contribute to improving its global Webometrics ranking due to the weakness of the relationship with activities of researchers in Algerian research laboratories. The result showed that the Algerian university is not interested in its virtual presence on the web, which negatively affected its Webometrics ranking. The researchers conclude that to improve the ranks of Algerian universities in various aspects, they must improve their global ranking according to the number of citations. Accordingly, to improve the ranking, international visibility of Algerian universities, decision-makers must adopt indicators of ‘research quality’ (number of citations), ‘research production’ (publications) in financing and accrediting research laboratories.

Since the coronavirus pandemic started, many people have died due to the disease. The epidemic has been challenging to predict, as it progresses and spreads throughout the world. We used Auto-Regressive Integrated Moving Average (ARIMA) models to predict the outbreak of COVID-19 in the upcoming months in Morocco. In this work, we measured the effective reproduction number using the real data and the forecasted data produced by the two commonly used approaches, to reveal how effective the measures taken by the Moroccan government have been in controlling the COVID-19 outbreak. The prediction results for the next few months show a strong evolution in the number of confirmed and death cases in Morocco. We study the spread of COVID-19 in Morocco to see how many cases are discovered, recovered, and dead, and the forecasting of further cases is used as a basic novel method. It is based on time series models. We used coronavirus outbreak data from March 02, 2020, to August 04, 2021. ARIMA (Autoregressive integrated moving average) and Prophet time-series models are used to forecast the development of COVID-19, which is not a novel method. The mean absolute error, root mean square error, and coefficient of determination R2 were computed to assess the model's performance. Our study aims to provide a better understanding of the infectious disease outbreak that affected Morocco. It also provides information on the disease outbreak's epidemiology. Our study shows that the FBProphet model is more accurate in predicting the prevalence of COVID-19. It can help guide the government's efforts to prevent the virus' spread.

Mature cystic teratoma is the most common type of ovarian germ cell neoplasm, but occasionally, it can undergo malignant transformations, especially in postmenopausal women. These secondary malignant neoplasms are most commonly squamous cell carcinomas. The absence of clinical and radiological specificity of this transformation means that the diagnosis remains purely histological. Data is insufficient regarding the appropriate management given their rarity. However, the treatment is multidisciplinary and is based on surgery and a platinum-based chemotherapy regimen. We report the case of a 53-year-old postmenopausal female patient with malignant transformation of the ovarian teratoma who was treated surgically and whose outcome was favorable. The diagnosis of the teratoma was evoked on imaging, while the diagnosis of squamous cell carcinoma was revealed on histology. Malignant transformation is an uncommon complication of mature ovarian teratomas. No clinical, radiological, or biological sign is specific; therefore, resection of any ovarian mass, even asymptomatic, is required.

Mobile network operators (MNOs) continually look to improve their business and become more agile and competitive within the quickly developing telecommunications industry. In turn, telecommunication professionals put forward and adapt advanced models and frameworks to assist MNOs to achieve their goals. In this context, the Business Process Framework (eTOM) was established by the TeleManagement Forum and on which we base this work to suggest a mapping of this eTOM business process model upon the network functions virtualization (NFV) framework. Thereby, the main purpose is to design a hybrid architecture by the combination of the aforementioned frameworks for dynamic service delivery with improved resource performance and quality of service so as to fulfill some of the purposes of the 5 generation (5G) technology with regard to a telecommunication system managed and orchestrated in a virtualized environment. Indeed, MNOs will be in a position to scale mobile services up and down fast and reduce costs to better align them with network usage. These procedures are performed based on flexible service chaining through implemented NFV management and orchestration modules along with SDN controller functions. In this article, we outline possible designs and analyses of flexible mobile service chaining to support end-to-end network slicing for dynamic service provisioning in order to provide a novel approach in the framework of the 5G technology, more especially from data and signaling based network perspectives. We project our proposal onto the IP Multimedia Subsystem (IMS) core network to discuss both dynamic and static signaling service provisioning approaches. In this situation, we set up a testbed platform with the goal of assessing the behavior of a virtualized IMS system, in a static signaling service provisioning environment through two signaling service chains to validate part of our proposed approaches. Experiment results confirm that virtualized IMS signaling resource performance indicators could be enhanced in the case of unpredicted performance degradation of one of the virtualized signaling resources assigned to the IMS virtual network functions composing the main signaling service chain by instantiating a second signaling service chain. Finally, IMS application performance indicators are improved regarding registration delay and session setup time.

AIMS/BACKGROUND: Focal treatment of diabetic macular oedema is usually done using a haemoglobin absorbing wave-length, such as argon green laser. This study aimed to compare photocoagulation with argon green (514 nm) and krypton red (647 nm), which is poorly absorbed by haemoglobin, in the focal treatment of patients with diabetic exudative maculopathy. METHODS: A total of 151 eyes of 78 outpatients were assigned randomly to receive either argon green (n = 79) or krypton red (n = 72) laser treatment. Pretreatment and post-treatment ocular examinations included visual acuity, fundus biomicroscopic examination, and fluorescein angiography. A total of 141 eyes of 73 patients were available for evaluation after 1 year follow up. RESULTS: No statistically significant difference was found between the two treatment groups with respect to visual acuity results, resorption of hard exudates, and resolution of focal retinal oedema. CONCLUSION: Krypton red laser was effective in the treatment of diabetic exudative maculopathy. Our data suggest that differential absorption of the various wavelengths by haemoglobin within microaneurysms may not be an important factor for ultimate success of focal treatment. [ABSTRACT FROM PUBLISHER]

OBJECTIVE:Health related quality of life (HRQL) of children using medical technology at home is largely unknown. Our aim was to examine the HRQL in children on long-term ventilation at home (LTHV) in comparison to a cohort using an enterostomy tube. STUDY DESIGN:Participants were divided into three groups: 1) LTHV without an enterostomy tube (LTHV cohort); 2) Enterostomy tube (GT cohort); 3) LTHV with an enterostomy tube (LTHV+GT cohort). Caregivers of children ≥ 5 years and followed at SickKids, Toronto, Canada, completed three questionnaires: Health Utilities Index 2/3 (HUI2/3), Caregiver Priorities Caregiver Health Index (CPCHILD), and the Paediatric Quality of Life Inventory (PedsQL). The primary outcome was the difference in utility (HUI2/3) scores between the cohorts. RESULTS:One hundred and nineteen children were enrolled; 47 in the LTHV cohort, 44 in the GT cohort, and 28 in the LTHV+GT cohort. In univariate analysis, HUI2 mean (SE) scores were lowest for the GT cohort, 0.4 (0.04) followed by the LTHV+GT, 0.42 (0.05) and then the LTHV cohort, 0.7 (0.04), p = 0.001. A similar trend was seen for the HUI3 mean (SE) scores: GT cohort, 0.1 (0.06), followed by the LTHV +GT cohort, 0.2 (0.08) and then the LTHV cohort, 0.5 (0.06), p = 0.0001. Technology cohort, nursing hours and the severity of health care needs predicted HRQL as measured by the HUI2/3. CONCLUSION:The HRQL of these children is low. Children on LTHV had higher HRQL than children using enterostomy tubes. Further work is needed to identify modifiable factors that can improve HRQL.

The adsorption of chromate on octacalcium phosphate (OCP) was investigated as a function of contact time, surface coverage, and solution pH [...]

Extraction methods depend mainly on the chemical nature of the extracted molecule. For these reasons, the selection of the extraction medium is a vital part of obtaining these molecules. The extraction of antimicrobial peptides (AMPs) from extremophile plants is important because of its potential pharmaceutical applications. This work focused on the evaluation of several solvents for the extraction of AMPs from the following two extremophile plants: Astragalus armatus and Anthyllis sericea from southern Tunisia. In order to identify the most efficient solvents and extraction solutions, we used sulfuric acid, dichloromethane, phosphate buffer, acetic acid and sodium acetate, and we tested them on leaves and roots of both the studied plants. The extracts obtained using sulfuric acid, dichloromethane and phosphate buffer extraction did not show any antimicrobial activity, whereas the acetic acid and sodium acetate extracts led to growth inhibition of some of the tested bacterial strains. The extracts of leaves and roots of An. sericea and As. armatus obtained by acetic acid and sodium acetate were proven to be active against Gram-positive bacteria and Gram-negative bacteria. Therefore, the most appropriate solvents to use for antimicrobial peptide extraction from both plants are acetic acid and sodium acetate.

A cross-sectional study was conducted in five regions in Saudi Arabia to investigate the epidemiology of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in dromedary camels (Camelus dromedarius) during April and May2015. Serum and nasal swab samples were tested for MERS-CoV antibodies andribonucleic acid (RNA) using a recombinant enzyme-linked immunosorbent assay (rELISA) and real-time reverse-transcription polymerase chain reaction (rRT-PCR), respectively. The overall MERS-CoV antibody seroprevalence was 80.5%, whereas the overall viral RNA prevalence was 2.4%. The associations of risk factors with each prevalence were quantified using univariate and multivariate analyses. The multivariate models identified region, age, grazing system, exposure to wild animals and dung removal as factors significantly associated with seroprevalence (p ??0.05). A higher seroprevalence was more likely to occur in camels from the Riyadh, Eastern, Northern and Makkah regions than those from the Jazan region; camels ??4 and 1-3 years of age (marginally significant) than calves < 1 year; and camels raised in zero grazing and semi-open grazing systems than those raised in an open grazing system. However, the presence of wild animals and daily dung removal were negatively associated with seroprevalence. On the other hand, region and sex were significantly associated with MERS-CoV RNA prevalence(p ??0.05). A higher viral RNA prevalence was more likely to occur in camels from the Riyadh region and Eastern region (marginally significant) than in those from the Makkah region, and in male camels than female camels. In conclusion, the risk factors identified in this study can be considered to be predictors of MERS-CoV infection in camels and should be taken into account when developing an efficient and cost-effective control strategy., (© World Organisation for Animal Health (OIE), 2018)

We report a case of central artery obstruction in a 55-year old man who had non proliferative diabetic retinopathy. Three years later, examination found no diabetic retinopathy in the eye that had central artery obstruction, and more advanced non proliferative diabetic retinopathy in the fellow eye. Pathogenic mechanisms for diabetic retinopathy regression after central artery occlusion could be the optic atrophy and ischemia of the inner retina associated to the decrease in retinal blood flow.

Nd:YAG capsulotomy is currently performed after extracapsular cataract surgery and seems to increase the risk of postoperative retinal detachment. In order to evaluate the incidence of this complication in our experience, we retrospectively studied 144 patients who underwent Nd:YAG laser posterior capsulotomy with at least a six-month follow-up. Six patients out of 144 (4.16%) subsequently developed rhegmatogenous retinal detachment. The average time from extracapsular cataract surgery to YAG capsulotomy was 21 months (11 to 26 months). The average time from capsulotomy to retinal detachment was 3.6 months (1 to 8 months). In 4 out of 6 eyes, at least one risk factor for retinal detachment was present (myopia, lattice degeneration, retinal detachment in the fellow eye). Vitreous cells were observed in 4 patients after capsulotomy. In 2 patients, a prophylactic laser photocoagulation had been previously performed. These retinal detachments were not different from aphakic or pseudophakic detachment, but the examination of retinal periphery was particularly difficult because of the peripheral capsular fibrosis, hiding retinal tears in 4 eyes. Two cases of moderate proliferative vitreoretinopathy were observed. Retinal reattachment surgery was successful in all cases with one procedure. The YAG laser energy required to create a capsulotomy was less than that reported in the literature, and no relationship could be established with the total energy applied. Nd:YAG capsulotomy seems to moderately increase the risk of retinal detachment, especially in myopic patients. The mechanisms of vitreous and retinal damage after Nd:YAG capsulotomy are discussed.