EFFECT OF CERATONIA SILIQUA AND CUCURBITA PEPO SEEDS EXTRACTS ON SPERMATOGENESIS IN MALE MICE

Worldwide, a percentage close to 50% of infertility cases is due to male-related problems including spermatogenesis defects, the process that determines sperm cells’ number and thus male fertility. Spermatogenesis is controlled by different hormones including the luteinizing hormone (LH), the follicle stimulation hormone (FSH), and testosterone. LH stimulates the Leydig cells to synthesize testosterone. FSH acts synergistically with testosterone. There is no current efficient treatment for spermatogenesis defects and people are reverting to natural remedies among which are the pumpkin and carob seeds. This study aims to evaluate the effects of pumpkin and carob seeds’ aqueous extracts on spermatogenesis and different sperm parameters in Balb/c mice. Carob seed (2%) and pumpkin seed (8%) aqueous extracts were prepared then administered to six mice groups by gavage over a period of 10, 21 and 35 days. Sperm parameters were determined. The levels of LH, FSH and testosterone were measured by ELISA. The expression levels of PLCz1, Rhox 5 and Ras genes were determined by RT-PCR. Histological studies of the testis seminiferous tubules were performed. Results were statistically analyzed using GraphPad Prism. The results showed that both seed extracts have no effect on the onset of puberty. In mature mice, they caused an increased in LH, FSH and testosterone levels. They also caused an increase in the expression levels of PLCz1, Rhox 5 and Ras genes. The experiment proved the effectiveness of both seeds extracts as male fertility promoters improving spermatogenesis

Genome-wide association analysis provides insights into the genetic basis of photosynthetic responses to low-temperature stress in spring barley

Low-temperature stress (LTS) is among the major abiotic stresses affecting the geographical distribution and productivity of the most important crops. Understanding the genetic basis of photosynthetic variation under cold stress is necessary for developing more climate-resilient barley cultivars. To that end, we investigated the ability of chlorophyll fluorescence parameters (FVFM, and FVF0) to respond to changes in the maximum quantum yield of Photosystem II photochemistry as an indicator of photosynthetic energy. A panel of 96 barley spring cultivars from different breeding zones of Canada was evaluated for chlorophyll fluorescence-related traits under cold acclimation and freeze shock stresses at different times. Genome-wide association studies (GWAS) were performed using a mixed linear model (MLM). We identified three major and putative genomic regions harboring 52 significant quantitative trait nucleotides (QTNs) on chromosomes 1H, 3H, and 6H for low-temperature tolerance. Functional annotation indicated several QTNs were either within the known or close to genes that play important roles in the photosynthetic metabolites such as abscisic acid (ABA) signaling, hydrolase activity, protein kinase, and transduction of environmental signal transduction at the posttranslational modification levels. These outcomes revealed that barley plants modified their gene expression profile in response to decreasing temperatures resulting in physiological and biochemical modifications. Cold tolerance could influence a long-term adaption of barley in many parts of the world. Since the degree and frequency of LTS vary considerably among production sites. Hence, these results could shed light on potential approaches for improving barley productivity under low-temperature stress

Three-Level DTC Based on Fuzzy Logic and Neural Network of Sensorless DSSM Using Extended Kalman Filter

This paper presents a direct torque control is applied for salient-pole double star synchronous machine without mechanical speed and stator flux linkage sensors. The estimation is performed using the extended Kalman filter known by it is ability to process noisy discrete measurements. Two control approaches using fuzzy logic DTC, and neural network DTC are proposed and compared. The validity of the proposed controls scheme is verified by simulation tests of a double star synchronous machine. The stator flux, torque, and speed are determined and compared in the above techniques. Simulation results presented in this paper highlight the improvements produced by the proposed control method based on the extended Kalman filter under various operation conditions

Multi-Objective Optimization of a Solar Combined Power Generation and Multi-Cooling System Using CO2 as a Refrigerant

This paper proposes a new combined multi-cooling and power generation system (CMCP) driven by solar energy. Carbon dioxide is used as a refrigerant. A parabolic trough collector (PTC) is employed to collect solar radiation and convert it into thermal energy. The system includes a supercritical CO2 power system for power production and an ejector refrigeration system with two ejectors to provide cooling at two different evaporating temperatures. The CMCP system is simulated hourly with weather conditions for Tunisia. The PTC mathematical model is used to calculate the heat transfer fluid outlet temperature and the performance of the CMCP system on a specific day of the year. A 1D model of an ejector with a constant area is adopted to evaluate the ejector performance. The system’s performance is evaluated by an energetic and exergetic analysis. The importance of the system’s components is determined by an exergoeconomic analysis. The system is modeled using MATLAB software. A genetic algorithm is used for multi-objective optimization to determine the best values and solutions for the system’s design parameters. The optimal energy and exergy efficiencies were found to be 13.7 percent and 37.55 percent, respectively, and the total product unit cost was 31.15 USD/GJ

Multi-Objective Optimization of a Solar Combined Power Generation and Multi-Cooling System Using CO₂ as a Refrigerant

This paper proposes a new combined multi-cooling and power generation system (CMCP) driven by solar energy. Carbon dioxide is used as a refrigerant. A parabolic trough collector (PTC) is employed to collect solar radiation and convert it into thermal energy. The system includes a supercritical CO2 power system for power production and an ejector refrigeration system with two ejectors to provide cooling at two different evaporating temperatures. The CMCP system is simulated hourly with weather conditions for Tunisia. The PTC mathematical model is used to calculate the heat transfer fluid outlet temperature and the performance of the CMCP system on a specific day of the year. A 1D model of an ejector with a constant area is adopted to evaluate the ejector performance. The system’s performance is evaluated by an energetic and exergetic analysis. The importance of the system’s components is determined by an exergoeconomic analysis. The system is modeled using MATLAB software. A genetic algorithm is used for multi-objective optimization to determine the best values and solutions for the system’s design parameters. The optimal energy and exergy efficiencies were found to be 13.7 percent and 37.55 percent, respectively, and the total product unit cost was 31.15 USD/GJ

Simulation numérique de l’écoulement dans un éjecteur supersonique

International audience<p&gtCe travail présente une étude sur l’analyse de l’écoulement au sein de l’éjecteur et plus particulièrement du processus de recompression par chocs qui prend place le long de la tuyère secondaire. Les simulations numériques sont réalisées à l’aide du logiciel de CFD ANSYS- FLUENT.</p&gt<p&gtLes deux modes de fonctionnement de l’éjecteur (sans et avec flux induit) sont étudiés pour différentes valeurs de la pression génératrice primaire P1 comprises entre 2 et 5 bar. Dans un premier temps, les distributions axiales de la pression sont analysées. Ensuite, la structure de chocs est visualisée afin d’appuyer certaines conclusions. Des tests sur le choix du modèle de turbulence le mieux adapté en termes de représentation correcte des phénomènes physiques ont été réalisés. Il a été montré que le modèle k-oméga-SST semblait le mieux adapté pour prédire la structure de choc. Les résultats numériques obtenus à partir des simulations 2D axisymétriques sont très encourageants. Les performances de l’éjecteur en termes d’aspiration et d’entrainement de flux secondaire ont été déterminées numériquement et comparées aux données expérimentales. L’influence de la distance entre la section de sortie de la tuyère primaire et la section d’entrée de la chambre de mélange de l’éjecteur (facteur géométrique NXP) sur les performances de l’éjecteur a été ensuite analysée.</p&gt<p&gtAbstract – This paper describes the investigation of the flow within a supersonic ejector and more particularly the analysis of the shock recompression process which takes place along the secondary nozzle. Numerical simulations are performed using the CFD package Ansys-Fluent. The two operating modes of the ejector (without and with induced flow) are studied for different values of the primary stagnation pressure P1 between 2 and 5 bar. The impact of the distance between the outlet section of the primary nozzle and the inlet section of<br&gt</p&g