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Extrusion and hot compressing molding processes were used to create bio-polyethylene (BioPE) composites reinforced with argan byproducts (shell, pulp, and argan cake) as bio-fillers. The thermal stability of the composites wass analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Dynamical mechanical analysis and rheological testing were used to investigate their mechanical properties. The morphological results showed a good adhesion between the argan and BioPE matrix. More efficient mechanical properties have been distinguished in the case of argan byproduct-based composite. A higher Young’s modulus was noted for all the biocomposites compared to pure BioPE. Thermal analysis revealed that the addition of bio-filler to polymer reduced decomposition temperatures. This study provides an ecological alternative for upgrading the valorization of abundant and underutilized Moroccan biomass. Furthermore, the possibility of using argan byproducts in composite manufacturing will help open up new markets for what is currently considered waste.

Aims: The primary objectives of this study were to analyse the nationwide healthcare trajectories of heart failure (HF) patients in France, 2 years after their first hospitalization, and to measure sequence similarities. Secondary objectives were to identify the association between trajectories and the risk of mortality. Methods and results: A retrospective, observational study was conducted using data extracted from the Echantillon Généraliste des Bénéficiaires database, covering the period from 1 January 2008 to 31 December 2018. Follow‐up concluded upon death or at the end of the study. We developed a methodology specific to healthcare data by extracting frequent healthcare trajectories and measuring their similarity for use in a survival machine learning analysis. In total, 11 488 HF patients were included and followed up for an average of 2.9 ± 1.3 years. The mean age of the patients was 78.0 ± 13.2 years. The first‐year mortality rate was 31.7% and increased to 78.8% at 5 years. Fifty per cent of patients experienced re‐hospitalization for reasons related to cardiovascular diseases. We identified 1707 hospitalization sequences, and 21 sequences were associated with survival, while 15 sequences were linked to mortality. In all our models, age and gender emerged as the most significant predictors of mortality (permutation feature importance: 0.099 ± 0.00078 and 0.0087 ± 0.00018, respectively; weights could be interpreted in relative terms). Specifically, the age at initial hospitalization for HF was positively associated with mortality. Gender (male: 49.5%) was associated with poorer prognoses. Healthcare trajectories, including non‐surgical device treatments, valve replacements, and atrial fibrillation ablation, were associated with a better prognosis (permutation feature importance: 0.0047 ± 0.00011, 0.0014 ± 0.000073, and 0.00095 ± 0.000097, respectively), except in cases where these invasive treatments preceded or followed hospitalization for cardiac decompensation. The predominant negative prognosis sequences were mostly those that included HF‐related hospitalizations before or after other‐related hospitalizations (permutation feature importance: 0.0007 ± 0.000091 and 0.00011 ± 0.000045, respectively). Conclusions: We highlight the value of healthcare trajectories on frequent hospitalization sequences, mortality, and prognosis and indicate the necessary prognostic value of HF re‐hospitalization. Our work may be an essential tool for better identification of at‐risk patients in order to increase and improve personalized care in the future. [ABSTRACT FROM AUTHOR]

Hyoscyamus muticus L. subsp falezlez (Coss) Maire is a toxic species, highly responded to in the Algerian Sahara, and played an important role in the traditional medicine of the Tuareg. It is one of the Solanaceae richest in tropane alkaloids (especially atropine), which constitute a large group of secondary metabolites. The objective was to study its toxicity to exploit the data in the valorisation of this endemic species. The acute toxicity study and the calculation of the LD50 were carried out on Wistar mice and using the tinctures of the plant collected from the Adrara Sbaa station (southwest of Algeria). A histopathological examination of the organs after the mice dissection was carried out. LD50 determination from the plant tinctures confirmed its extreme toxicity and was estimated at 0.85± 0.27g/kg dry plant. Functional abnormalities were detected in the heart and liver of mice injected with the lethal dose (6.3g/kg); significant vasodilation was observed. Content of the results obtained, the toxicological potential of the plant has been highlighted especially in acute. However, it would be interest-ing to explore chronic toxicity. [ABSTRACT FROM AUTHOR]

This paper presents the detailed design, construction and tests of a protype iron-free MRI-compatible electromagnetic actuator. The originality of this proposal lies in the use of the homogeneous static magnetic field B0, present in the MRI bore, to ensure the electromechanical energy conversion. The armature is composed of three rectangular coils in a three-phase arrangement, which makes the actuator very light-weight and compact. The operating principle is that of an AC synchronous motor with a rotating armature. In order to design the actuator, a 3D analytical electromagnetic model is developed to predict the magnetic field produced by the armature winding. Then, a 3D finite element (FE) computation is performed to validate the analytically calculated magnetic field. The developed analytical model is then inserted into an optimization routine based on Genetic Algorithms (GAs) to obtain the prototype dimensions to be realized. Finally, the prototype is constructed and tested inside an MRI research scanner. The results indicate that the reduction in the Signal-to-Noise Ratio (SNR) and the geometrical distortion are less than 5% when the actuator is powered with a current of 10 times the rated one and when it is located very close to the subject to be imaged. [ABSTRACT FROM AUTHOR]

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AbstractThis study presents the buckling and lateral torsional buckling behaviors of thin-walled laminated composite or functionally graded sandwich I-beams. A refined beam model (RBT) based on the 3D Saint-Venant (SV) solution is used in this study to formulate the problem. This model allows for a realistic analysis of beams with arbitrary cross-sections and is free from the limitations of classical beam theories. The displacement models establish a consistent 1D beam theory that accurately captures the essence of the cross-section’s nature. The governing models consider cross-section deformations, including in and out of plane warpings and distortions derived from the 3D SV solution associated with the cross-section vibrational behavior. Furthermore, a user-friendly numerical tool called CSB (cross-section and beam analysis) is used to facilitate the implementation of this method. The numerical results are examined in detail and compared with previous works to investigate the influence of boundary conditions, angle-ply, shear effects, span-to-height ratio, and material distribution on the critical buckling loads of thin-walled I-beams. The results demonstrate that the RBT models accurately and efficiently analyze thin-walled I-beams under different loads and boundary conditions. Furthermore, some of the new results are presented as reference values for the future. [ABSTRACT FROM AUTHOR]

Background and Aim: Hexavalent chromium (Cr (VI)) compounds have been shown to induce nephrotoxicity associated with oxidative stress in humans and animals. The aim of the present study was to investigate the nephroprotective effect of bee propolis, as highly antioxidant natural product, in vivo using an animal model. Materials and Methods: First of all, total phenol and flavonoid contents of propolis sample were estimated in vitro. Afterward, to study the protective effect of propolis on renal damages caused by an injection of a single dose of potassium dichromate (15 mg/kg b.wt), 24 male Wister rats were divided into test and control groups. Propolis treatment was performed by oral gavage of 100 mg/kg b.wt/day, while the control groups received water instead. The 24 h urine was collected and blood samples were withdrawn before and after each treatment for further analysis. Results: Propolis revealed to be rich in polyphenols and flavonoids. Chromate provoked a nephrotoxic effect expressed by a drastic decrease in glomerular filtration assessed by creatinine clearance. However, the administration of propolis attenuated the renal damages induced by the chromate. This attenuation can be seen by the increase of creatinine clearance when comparing propolis treated group to the non-treated group. Conclusion: Propolis showed a protective potential against chromate-induced nephrotoxicity through the amelioration of chromate's toxic effects. It might be concluded that propolis could be effective as chemoprotectant in the management of potassium dichromate-induced nephrotoxicity.

Removing the gearbox from the single-motor configuration of an electric vehicle (EV) would improve motor-to-wheel efficiency by preventing mechanical losses, thus extending the autonomy of the EV. To this end, a permanent-magnet Vernier machine (PMVM) is designed to ensure such operation. This machine avoids the high volume and large pole-pair number of the armature winding since its operating principle resembles that of a synchronous machine with an integrated magnetic gear. Therefore, such a structure achieves low-speed and high-torque operation at standard supply frequencies. From the specification of an urban vehicle, the required specification for direct-drive operation is first determined. On this basis, an initial prototype of a Vernier Machine with permanent magnets in the rotor that can replace the traction part (motor + gearbox) is designed and sized. This first prototype uses radial contiguous surface-mounted magnets and its performance is then analyzed using finite element analysis (FEA), showing a relatively high torque ripple ratio. The rotor magnets are then arranged in a quasi-Halbach configuration and simulations are performed with different stator slot openings and different ratios of the tangential part of the magnet in order to quantify the effect of each of these two quantities in terms of average torque, torque ripples and harmonics of the back-electromotive force at no load. Since the design and optimization of this motor is finite element-assisted, a coupling process between FEA Flux software and Altair HyperStudy is implemented for optimization. This method has the advantages of high accuracy of the magnetic flux densities and electromagnetic torque estimates, and especially the torque ripples. The optimization process leads to a prototype with an average torque value that meets the specification, along with a torque ripple ratio below 5% and a high power factor, while keeping the same amount of magnet and copper.

Argan nut shell represents the most generated by-product during the process of the extraction of argan oil. For the first time, argan nut shell was characterized and assessed as a new potential feedstock for bioethanol production using a combination of mechanical and enzymatic pretreatment. Argan shell samples were first disintegrated using the Star Burst system, which involves a high-pressure water jet system. Then, the pretreated argan nut shell was subjected to enzymatic hydrolysis using Viscozyme L (30 FBGU/g). Afterwards, the fermentation of the hydrolysate by Saccharomyces cerevisiae was investigated. Argan nut shell, as a feedstock plentiful in carbohydrates, conferred a high yield of saccharification (90%) and an optimal ethanol bioconversion (45.25%) using Viscozyme L (30 FBGU/g) at 2%w/v of argan feedstock.

Smart office concepts are gaining increasing attention in the built environment domain, as they promise efficient and effective workplaces that cater to user needs. While previous researchers have primarily focused on Internet of Things (IoT) technologies in the office environment and their impacts on office users, few studies have addressed the users' preferences of smart office concepts. This study aims to fill this gap by investigating users' preferences for four smart features: smart parking, smart workspace booking, smart temperature control and smart lighting, and exploring how different attributes of these smart features influence users' preferences. The study conducted a stated choice experiment with 137 valid respondents and analysed the data using both Multinomial Logit (MNL) models and Latent Class (LC) models. The MNL model results indicate that users have varying preferences for different smart features and that there are significant interactive impacts between attribute levels and age, gender, working hours per week and attitudes towards technologies, highlighting the heterogeneity in users' preferences. The LC model revealed two distinct user classes for each smart feature, which have significantly improved the overall model performance. This study guides the design and implementation of smart office concepts that cater to users' needs and preferences. [ABSTRACT FROM AUTHOR]

Previous research has identified metrics that are applicable to both lean and agile strategies and has hypothesised that financial and efficiency metrics are more relevant to the lean supply chain strategy, while customer service and flexibility metrics are more relevant to the agile supply chain strategy. These metrics need to be assessed empirically to confirm their relevance and validate these hypotheses. Drawing upon contingency theory, which mandates that supply chain performance metrics should vary based on the supply chain strategy, the research methodology resulted in developing a survey instrument that has been subsequently tested in 45 large enterprises and analysed by Partial Least Square-Path Modelling using XLSTAT software v.2020.4. The results support the existing beliefs and suggest that financial and efficiency indicator sets are more applicable to the lean supply chain strategy, whereas customer service and flexibility indicator sets are more pertinent to the agile supply chain strategy. This research distinguishes itself, through its novelty, in validating an adaptable framework for supply chain performance metrics, acknowledging the necessity of developing a suitable supply chain performance system. Ultimately, the findings of this research might serve as an initial foundation for practitioners in shaping the design of supply chain performance systems since the strong relationship between SC strategies and specific metrics may serve as a strategic approach to evaluate and improve performance. [ABSTRACT FROM AUTHOR]

Analysing the role of the European Union (EU) in dealing with the Syrian crisis and the Assad regime exposes limitations in the development of a coherent and effective European foreign and security policy. The EU found itself reacting to external and internal pressures rather than acting on its own impetus. This was related to multiple factors: the fragmentation on the ground, associated with the challenges of a gradually increasing lack of consensus among member states and the proactive and competitive presence of external players, contributed to the failure of the EU's strategies. Ultimately, the combination of these elements has led the EU to reduce its involvement in conflict resolution in favour of a greater focus on its own internal disputes. [ABSTRACT FROM AUTHOR]

Objective(s): The effect of propolis collected in Morocco on blood glucose, lipid profile, liver enzymes, and kidney function was investigated in control and diabetic rats. Materials and Methods: Antioxidant activity of propolis was evaluated with the use of DPPH, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS•+), ferric reducing power and total antioxidant activity assay. To study its effect in streptozotocin (STZ)-induced diabetes, the rats were divided into eight groups; four control and four diabetics. The animals received distilled water, glibenclamide, or propolis extract, 50 mg/kg/BW) or 100 mg/kg/b.wt, daily for 15 days. Blood glucose, triglyceride, lactic acid dehydrogenase, liver enzymes, creatinine, blood urea, lipid profile, and body weight were measured on day 15 after commencement of the treatment. Results: Propolis has a strong antioxidant activity and high total flavonoids and polyphenols content. Glibenclamide and propolis have no significant effect on lipid parameters, and renal and hepatic function in non-diabetic rats. However, propolis or glibenclamide caused a significant lowering of blood glucose after a single administration and at day 15 after daily administration in diabetic rats (PConclusion: Propolis exhibited strong antihyperglycemic, antihyperlipidemic, and hepato-renal protective effects in diabetes, and significantly lowered the elevated lactic acid dehydrogenase. The study demonstrated for the first-time the effect of Moroccan propolis in diabetes and it will pave the way for clinical investigations.