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The main objective of this work was the valorization of various biowastes to extract biocellulose for carbon fiber synthesis as a subsequent application. The effectiveness of cellulose extraction was investigated by two methods: maceration extraction and Soxhlet process. The extracted cellulose was characterized using a range of analytical techniques: thermogravimetric analysis/differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and energy-dispersive X-ray (EDX) analysis. The purity of extracted cellulose was successfully confirmed by FTIR and EDX results, which indicated the presence of major functional groups characteristic of cellulose structure. The cellulose extraction yield from prickly pear seeds was 39.3% by maceration and 23.18% using the Soxhlet extraction method.

Abstract As a new investigation for renewable energy generation, the recent three-layer solar structure is composited with three effective material usages of Al (resonator), InSb (substrate), and Ag (based). The overall wavelength of overall 2800 nm with the bandwidth order from 0.2 to 3.0 μm is 91.68%, the extracted percentage is 97.07% at 800 nm (1.41–2.21) µm, and the output is 95.02% with the 1420 nm wavelength by the bandwidth separation of 1.09 and 2.51 μm respectively. With the graphene accumulation in this absorber, the radiated output can be determined in the first visible area, the second ultraviolet region, and the near-infrared spectra respectively. The multi-step exploration of the absorbed rate in design performance, the selected materials and parameter assignments, and the analyzed parametric numbers for each layer will be included in the proposed presentation. The demonstrated solar structure can be performed at the low-temperate rate of less than 100 °C for heating processes of water or space, between 100 and 250 °C for industrial processes, and above 250 °C to release the steam for running turbines in the electricity generation.

Abstract Because energy interest demands clean and sustainability in the last ten years. Solar thermal energy conversion, where sunlight can be absorbed to convert it into heat can stand as an alternative for this purpose. Graphene dispersed with different substrates enables us to get torsion control over light absorption and heat transport. This work discusses the optothermal properties of graphene-based coatings on different substrates such as CuO, MAPBI3, Fe, etc. The optothermal properties of such CuO-graphene, MAPBI3-graphene, and Fe-graphene combinations display the highest average absorptance of 96.8% across the solar spectrum between 0.2 and 2.5 μm followed by 86.7% by MAPBI3-graphene. However, Fe-graphene depicts a significantly lower value of 24.3%. A critical inspection of these optothermal properties would enrich one with critical knowledge of design optimisation in graphene-coated solar absorbers. Thus, the data collection time is greatly reduced using ML compared to running simulations which have a step size of about 8 h per change. Where the machine learning efficacy is 98% for the thickness optimization of Fe, CuO, and MAPBI3 with 25% test data. Of much potential interest are the solar absorbers developed using these materials in fields such as solar thermal energy harvesting, air/water heaters, and industrial heating systems.

Abstract This investigation presents extensive computational analyses of the compressible flow near ramp injector with double circular injectors at supersonic combustor of scramjet engine. Comparison of the fuel mixing and fuel jet penetration of hydrogen jet are done for two injector configurations at free stream Mach number of 2. The simulation of the supersonic flow near ramp injector is done via solving RANS equations with computational fluid dynamic technique. Effect of nozzle space on the fuel distribution and mixing mechanism has been investigated. Besides, interface of the free stream and jet behind the ramp are fully analyzed. Comparison of the circulation strength behind these two configurations indicates that increasing of the jet space led to higher circulation strength. However, the mixing efficiency of the model with low jet space is higher since the interaction of these two jet is key factor for diffusion and mixing inside the combustion chamber.

Metacognitive awareness of reading strategy has a significant impact on language learning. It addresses how students organize context-based interactions and how they may employ reading comprehension strategies. Saudi students of English still face reading comprehension issues that significantly affect their overall language learning. Therefore, this mixed method study sought to assess Saudi English students' metacognitive awareness of reading strategies, determine whether gender and university level affect their use of these strategies, and explore English instructors' views on this issue. Two instruments were used to achieve these objectives. Two hundred ten students were surveyed for quantitative data. 15 English instructors were interviewed in a semi-structured manner for qualitative data. Descriptive statistical analysis was used to analyze the quantitative data gathered, while pattern matching and thematic content analysis were applied to analyze the qualitative data. The results demonstrated that Saudi EFL students' metacognitive awareness of reading methods was generally moderate. This awareness was moderate regarding the use of global reading strategies and low regarding support and problem-solving strategies. The metacognitive awareness levels for global strategies vary significantly by gender, in favour of females. Senior and junior university students had better global and support reading methods than freshmen. The qualitative data from the interview supported the quantitative data suggesting Saudi EFL students had low to moderate metacognitive awareness. Their low-to-moderate level explains their poor reading comprehension. Based on these findings, limitations and recommendations are given.

Writing apprehension is an overwhelming feeling of stress and anxiety when writing in a foreign language. In the past ten years, it has been a hot topic of debate. Due to its influence on writing quality, this study aimed to investigate this topic among a group of university EFL students, measuring the level of this apprehension and identifying its main factors. To accomplish this objective, 137 Saudi EFL students were given a questionnaire containing 26 statements spanning four essential writing apprehension factors on a five-point Likert scale. The results indicated that Saudi EFL students generally received moderate writing apprehension. Negativity towards writing was the furthermost common factor of writing apprehension. Self-efficacy in writing was regarded as the least apprehensive factor compared to other writing apprehension factors. The potential causes of this apprehension in each factor were addressed. Statistically significant gender and university level differences were found favouring males and beginner university levels for negativity towards writing. Based on these findings, limitations and future study recommendations are suggested.

Hematocolpos is a gynecological disorder characterized by the accumulation of menstrual blood in the vagina due to anatomical obstruction, often resulting from an imperforate hymen (IH), the most common etiology in approximately 90% of cases. This condition can remain undiagnosed until adolescence, when menarche triggers clinical symptoms such as cyclical lower abdominal pain, primary amenorrhea, and in severe cases, a rapidly enlarging pelvic mass. Complications may include urinary retention, constipation, and infection if not promptly treated. Early diagnosis and intervention are crucial to prevent long-term consequences such as endometriosis, retrograde menstruation, and infertility. In Tunisia, the hymen holds significant cultural and social value, symbolizing virginity and moral purity, complicating the surgical management of hematocolpos. This case report discusses the surgical and cultural considerations involved in the treatment of a 13-year-old Tunisian girl diagnosed with hematocolpos. A hymen-sparing hymenotomy was selected, preserving the hymenal ring while creating an adequate orifice for menstrual flow, ensuring a balance between medical treatment and cultural sensitivities. The procedure, which included drainage of 600 ml of retained blood and meticulous suturing to maintain the hymen’s appearance, was successful. The patient experienced regular menstrual cycles and expressed satisfaction with the outcome 12 months postoperatively. This case highlights the importance of providing culturally sensitive care in regions where the hymen holds symbolic value. Virginity-sparing surgical techniques offer a suitable approach that addresses both medical and social concerns, ensuring patient well-being while respecting cultural beliefs.

Background: Since 2012, the northeast region of Tunisia has witnessed an increase in dog rabies cases, indicating a concerning emergence of the disease. Previous studies have indicated the widespread nature of rabies in northern Tunisia. However, there remains a lack of comprehensive understanding regarding the associated risk factors. Aim: This study aimed to identify potential risk factors associated with the occurrence of dog rabies in northeast Tunisia through a case-control approach. Methods: A case-control study was conducted, involving a cases group (n=77) consisting of dogs confirmed positive for rabies at the referral laboratory using the Fluorescent Antibody Test (FAT) between 2013 and 2019. The controls group (n=77) comprised both negative cases received at the laboratory and dogs that underwent a 15-day quarantine period and received a certificate of absence of rabies after observation. Univariate and multivariate logistic regression analyses were performed to explore various potential risk factors, including age, sex, breed, confinement, vaccination status, presence of bites, ownership status, origin of dogs, geographic sector, presence of rabies cases, and proximity to slaughterhouses. Results: The final logistic regression model revealed several significant findings. The odds of an unconfined dog being affected by rabies were nearly twice as high as for confined dogs (OR=1.9; 95% CI: 1.17 to 3.27). Furthermore, the odds of rabies occurrence were 25 times higher in areas where rabies cases had been reported within the previous three months to one year compared to uninfected areas (OR=25.7; 95% CI: 3.02-219.14). Dogs born at home to the owner's bitch were also found to be at significantly higher risk of rabies (OR=2.41; 95% CI: 1.14-5.13). Additionally, residing in areas with reported rabies cases in the last three months was found to increase the risk of rabies by 2.8 times (OR=2.8; 95% CI: 1.16-6.77). However, vaccination was associated with a 1.6-fold reduction in the risk of contracting rabies (OR=0.6; 95% CI: 0.38-0.97). Conclusion: This study provides valuable insights into the risk factors associated with dog rabies in northeast Tunisia. The findings underscore the importance of implementing targeted control measures, such as increased vaccination coverage and enhanced confinement measures, to mitigate the spread of rabies in the region. These findings can inform decision-making processes aimed at improving the effectiveness of national rabies control programs. [Open Vet J 2024; 14(11.000): 2745-2753]

Abstract The role of efficient fuel mixing and a stable flame holder is crucial in enhancing the performance and capabilities of scramjet engines for high-speed flight. The present research paper has tried to disclose the fuel mixing efficiency of 3-lobe annular nozzle on the mixing mechanism of the fuel jet behind the strut. In addition, using internal air jet flow for increasing the circulation strength and fuel mixing behind the strut is also examined in this study. Numerical simulation of the flow and fuel jet behind the strut is done to reveal the main physics related to the mechanism of fuel mixing inside the combustor with the proposed injection system. The results of our simulation show that using annular 3-lobe fuel jet improve the fuel mixing via production of the multiple vortex pairs within the combustor behind the strut. The use of internal air jet also enhances the fuel mixing efficiency up to 90% in combustor of scramjet engine.

Phyllodes tumor of the breast is a rare fibroepithelial tumor, constituting less than 1% of all breast neoplasms. These tumors are characterized by rapid stromal growth and can reach significant sizes, particularly in malignant cases, necessitating aggressive surgical management due to their high recurrence risk. In this case report, we present a 40-year-old Tunisian woman diagnosed with a giant phyllodes sarcoma. The patient experienced considerable physical and psychological impacts, including impaired mobility, body image disruption, and professional limitations. Clinical examination and imaging confirmed the presence of a large lobulated mass in the left breast, with no signs of distant metastasis. A multidisciplinary team recommended a total mastectomy with immediate reconstruction using a latissimus dorsi myocutaneous flap. This approach aimed to restore breast contour while addressing both oncologic and aesthetic needs. The procedure was successful, with the excised tumor weighing 7 kg. Postoperatively, the patient received close monitoring and psychological support, emphasizing the importance of a holistic approach to recovery. This case underscores the complexities of managing giant phyllodes sarcoma, highlighting the value of a timely surgical intervention combined with effective reconstructive techniques. It also emphasizes the need for individualized treatment plans that consider both functional and aesthetic outcomes to optimize patient recovery and quality of life

Background Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) mainly affects the respiratory tract, but different organs may be involved including the kidney. Data on acute kidney injury (AKI) in critical forms of coronavirus disease 2019 (COVID-19) are scarce. We aimed to assess the incidence, risk factors and prognostic impact of AKI complicating critical forms of COVID-19. Methods A retrospective descriptive case/control monocentric study conducted in a medical intensive care unit of a tertiary teaching hospital over a period of 18 months. Results We enrolled 144 patients, with a mean age of 58±13 years old and a male predominance (sex-ratio: 1.25). Forty-one (28%) developed AKI within a median of 4 days (Q1: 3, Q3: 8.5) after hospitalization. It was staged KDIGO class 3, in about half of the cases. Thirteen patients underwent renal replacement therapy and renal function improved in seven cases. Diabetes (OR: 6.07; 95% CI: (1,30-28,4); p: 0.022), nephrotoxic antibiotics (OR: 21; 95% CI: (3,2-146); p: 0.002), and shock (OR: 12.21; 95% CI: (2.87-51.85); p: 0.031,) were the three independent risk factors of AKI onset. Mortality was significantly higher in AKI group (HR:12; 95% CI: (5.81-18.18); p:0.041) but AKI didn’t appear to be an independent risk factor of poor outcome. In fact, age > 53 years (p: 0.018), septic shock complicating hospital acquired infection (p: 0.003) and mechanical ventilation (p Conclusions The incidence of AKI was high in this study and associated to an increased mortality. Diabetes, use of nephrotoxic antibiotics and shock contributed significantly to its occurrence. This underlines the importance of rationalizing antibiotic prescription and providing adequate management of patients with hemodynamic instability in order to prevent consequent AKI.

Engineers are motivated to pursue green energy to mitigate the effects of climate change and generate sustainable electricity. Three materials are employed in an effective solar design: chromium (Cr) as a resonator, silicon dioxide (SiO2) as an intermediate layer, and silver (Ag) applied as a base part. This design harvests radiation in various light regions, including ultraviolet, visible, and near-infrared. The bandwidth exploration for 2800 nm (0.2–3 µm), 1300 nm (0.2–1.5 µm), and 800 nm (0.2–1 µm) wavelengths is 90.24 %, 95.4 %, and 97.6 %, respectively. The proposed essay explores many approaches to presenting the current design. Design and parameters are investigated to express layer parameters and design building processes using variation analysis in all parameter sections. We examined the ML model’s ability to accurately predict outcomes by varying its parameters. The highest achieved R2 value was 0.996353, obtained with a 0.25 test number. Additionally, the mean squared error was 3.22497 x 10-5. Compared to similar published studies, the current K-shaped design can optimize machine learning and graphene inclusion for high absorption output in household and industrial applications. The current K-shaped absorbed heat concentrates on solar heat for cooling, baking, heating, drying, cooking, and smoking at home. However, large industries can utilize it for sterilizing, viscosity control, washing, boiler preheating, and more.

Background Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) mainly affects the respiratory tract, but different organs may be involved including the kidney. Data on acute kidney injury (AKI) in critical forms of coronavirus disease 2019 (COVID-19) are scarce. We aimed to assess the incidence, risk factors and prognostic impact of AKI complicating critical forms of COVID-19. Methods A retrospective descriptive case/control monocentric study conducted in a medical intensive care unit of a tertiary teaching hospital over a period of 18 months. Results We enrolled 144 patients, with a mean age of 58±13 years old and a male predominance (sex-ratio: 1.25). Forty-one (28%) developed AKI within a median of 4 days (Q1: 3, Q3: 8.5) after hospitalization. It was staged KDIGO class 3, in about half of the cases. Thirteen patients underwent renal replacement therapy and renal function improved in seven cases. Diabetes (OR: 6.07; 95% CI: (1,30-28,4); p: 0.022), nephrotoxic antibiotics (OR: 21; 95% CI: (3,2-146); p: 0.002), and shock (OR: 12.21; 95% CI: (2.87-51.85); p: 0.031,) were the three independent risk factors of AKI onset. Mortality was significantly higher in AKI group (HR:12; 95% CI: (5.81-18.18); p:0.041) but AKI didn’t appear to be an independent risk factor of poor outcome. In fact, age > 53 years (p: 0.018), septic shock complicating hospital acquired infection (p: 0.003) and mechanical ventilation (p

As worries about climate change and energy security grow, the need for clean and sustainable energy sources becomes increasingly critical. Among the possible alternatives, solar thermal technology provides a dependable and adaptable method for harnessing the sun's energy as heat. At the core of this technique is the solar thermal absorber, a critical component that converts sunlight into useful thermal energy. The Graphene Based Disk-Square Integration Resonator Solar Absorber (GBDSIRSA) structure is examined in this work between 200 and 2500 nm in wavelength. The GBDSIRSA has remarkable performance throughout a wide variety of spectral ranges, underscoring its adaptability and effectiveness. GBDSIRSA has exceptional efficiency in absorbing light over the full spectrum, from UV to MIR wavelengths, with an average absorptance of 97.73%. The absorptance rates are particularly high, achieving 94.02% in the UV, 96.36% in the VIS, 97.12% in the NIR, and an astounding 98.94% in the mid-infrared (MIR) region. The GBDSIRSA is independent of polarization effect and also an incident angle independent up to 80 degrees. The machine learning (Local Regression) approach used with test size of 0.2 and 1.8780 ×10-5 mean squared error for absorptance prediction has good prediction accuracy R2 of more than 95% which is applied to simulation resource reduction. Because of its wide absorptance spectrum, polarization and incident angle independence, the GBDSIRSA is a very promising technology for a variety of applications, including thermal imaging and renewable energy. It can efficiently harvest solar energy. All things considered, GBDSIRSA's remarkable absorptance properties highlight its promise as a top choice for cutting-edge optical and solar energy applications.

Malcolmia aegyptiaca (locally known as El Harra) and Matthiola livida (locally known as Chegara) are medicinal plants traditionally used to relieve pain and reduce inflammation. Little is known about the flavonoid content or the analgesie and anti-inflammatory properties of these plants.

Introduction: Metacognitive strategies, including planning, control, and regulation, are crucial in enhancing learning outcomes and academic success. This cross-sectional study aimed to examine the utilization of metacognitive learning strategies among nursing students and their association with academic performance. Methods: The study was conducted at a nursing institute and included participants from various semesters in the nursing program. A questionnaire was used to assess the use of metacognitive strategies and students’ academic performance. Data were analyzed using descriptive statistics, t-tests, and correlation analysis. Results: The results showed that a higher percentage of students reported "good use" of metacognitive strategies. Females tended to use these strategies more frequently than males. Additionally, students in higher semesters demonstrated better utilization of the strategies compared to those in lower semesters. There was a significant positive correlation between academic performance and the utilization of the regulation strategy. Discussion: The findings highlight the importance of fostering metacognitive learning strategies to enhance academic achievement in nursing education. Educators and institutions can use these findings to improve students' learning experiences and academic outcomes. Further research is needed to explore the long-term effects of metacognitive training in nursing education.

We investigate some nonlinear elliptic problems of the form \Delta^2v + \sigma(x) v= h(x,v)\quadin \Omega,\quad v=\Delta v=0 \quadon \partial\Omega, \eqno({\rm P}) where $\Omega$ is a regular bounded domain in $\mathbb{R}^N$, $N\geq2$, $\sigma(x)$ a positive function in $L^{\infty}(\Omega)$, and the nonlinearity $h(x,t)$ is indefinite. We prove the existence of solutions to the problem (P) when the function $h(x,t)$ is asymptotically linear at infinity by using variational method but without the Ambrosetti-Rabinowitz condition. Also, we consider the case when the nonlinearities are superlinear and subcritical.

Abstract It observers that an object is submerged in a liquid, more pressure is applied to its bottom surface than its top surface, as a result pressure rises within depth of fluids. A buoyancy force is generated due to the pressure difference. In the current investigation, the mathematical formulation of bio-convective stagnation point flow of a radiative Maxwell fluid with multiple slip effect on an exponentially porous stretching surface is analyzed thoroughly. The buoyancy assisting and opposing conditions with magnetic field are discussed in the current investigation. Moreover, the energy and concertation equations are formulated by the utilization of Cattaneo–Christov theory and non-uniform heat source/sink. The flow model is developed in the form of partial derivatives, then use the similarity variables to convert the physical system into nonlinear ordinary derivative. The nonlinear system is tackled numerically with the help of Bvp4c approach on the MATLAB. The graphical upshots for various emerging parameter are observed with two aspects: buoyancy assisting $$\left( {\lambda > 0} \right)$$ λ > 0 and buoyancy opposing $$\left( {\lambda < 0} \right)$$ λ < 0 . The observation shows that the greater values of mixed convection parameter improves the fluid velocity for assisting flow $$\left( {\lambda > 0} \right)$$ λ > 0 , while declining trend is noticing for opposing flow situation $$\left( {\lambda > 0} \right)$$ λ > 0 . Further, it is worth noticing that stronger inputs of thermal and concentration relaxation parameter yield lesser thermal and concentration diffusivity, which reduces the temperature and nanoparticles concentration.