Effect of Temperature on the AlGaAs/GaAs Tandem Solar Cell for Concentrator Photovoltaic Performances

Multijunction solar cells for concentrator photovoltaic (CPV) systems have attracted increasing attention in recent years for their very high conversion efficiencies. But there is a problem in this type of solar cells (CPV) is to increase the temperature if it has been augmenting the concentration ratio. In this paper, we studied the effect of the concentration photovoltaic in a high-efficiency double-junction devices solar cell on temperature solar cell and its impact on the photocurrent, the efficiency and open circuit voltage. In this study, the top cell is made of AlGaAs (1.73 eV) while the bottom cell is made of GaAs (1.42 eV) between them a tunnel junction

Caractérisation hydrogéochimique des eaux souterraines du complexe aquifère Morsott-Laouinet (Région Nord de Tébessa, Sud-Est algérien)

L’analyse des eaux souterraines de l’aquifère superficiel Plio-Quaternaire, pose à nouveau la question de l’importance des faciès gypso-salifères dans la région de Morsott-Laouinet au Nord de Tébessa dans le Sud Est algérien. Ces faciès sont représentés par des affleurements triasiques en surface et par la présence d’un substratum marno-salifère en profondeur. Les analyses chimiques de la totalité des puits de la région le confirment.La salinité des eaux est très variable et généralement élevée. La  conductivité électrique de l’eau oscille entre 1154 μS cm-1 et 23800 μS cm-1 avec une concentration élevée d’amont en aval dans le sens de l’écoulement qui se fait du Sud vers le Nord. Les faciès chimiques extrêmes sont le bicarbonaté calcique et le chloruré sodique avec une prédominance de ce dernier. Les teneurs en chlorures et en sodium pouvant atteindre localement les valeurs respectives de 8145 mg l-1 et 3988 mg L-1. La comparaison de la teneur en chlorures avec le reste des éléments majeurs et le strontium, montre que la salinité des eaux souterraines de la plaine de Morsott-Laouinet possède deux origines possibles : la dissolution-précipitation de la roche aquifère et du substratum et l’échange de base entre le sodium et les éléments qui lui sont semblables.Mots-clés : Trias, aquifère, salinité, saturation, Morsott-Laouinet

Plyometric exercise combined with high-intensity interval training improves metabolic abnormalities in young obese females more so than interval training alone

International audienceThe aim of this study was to compare the effects of 12 weeks of high-intensity interval training (HIIT) with the effects of 12 weeks of plyometric exercise combined with HIIT (P+HIIT) on anthropometric, biochemical, and physical fitness data in young obese females. Sixty-eight participants (age, 16.6 ± 1.3 y; body mass, 82.8 ± 5.0 kg; body fat, 39.4% ± 3.3%; body mass index z score, 2.9 ± 0.4) were assigned to 1 of 3 groups: HIIT (2 blocks per session of 6-8 bouts of 30-s runs at 100% velocity at peak oxygen uptake, with 30-s active recovery between bouts at 50%velocity at peak oxygen uptake (n = 23)); P+HIIT (2 blocks per session of 3 different 15-s plyometric exercises with 15-s passive recoveries, totaling 2 min for each plyometric exercise + the same HIIT program (n = 26)); or control (no exercise (n = 19)). Anthropometric (body mass, body mass index z score, body fat, lean body mass, and waist circumference), biochemical (plasma glucose, insulin, leptin and adiponectin concentrations, leptin/adiponectin ratio, and homeostasis model assessment of insulin resistance (HOMA-IR)), physical fitness (peak oxygen uptake, velocity at peak oxygen uptake, squat jump, and countermovement jump performances), and energy intake data were collected. Both training programs improved the anthropometric, biochemical, and physical fitness variables. However, the P+HIIT program induced greater improvements than did the HIIT program in lean body mass (+3.0% ± 1.7%), plasma glucose and leptin concentrations (-11.0% ± 4.7% and -23.8% ± 5.8%, respectively), plasma leptin/adiponectin ratio (-40.9% ± 10.9%), HOMA-IR (-37.3% ± 6.2%), and squat jump performance (22.2% ± 7.5%). Taken together, these findings suggest that adding plyometric exercises to a HIIT program may be more beneficial than HIIT alone in obese female adolescent

Renal cell carcinoma in children: Case report and literature review

Renal cell carcinoma is infrequent in children; consequently it is important to communicate its diagnosis and follow up. The behaviour of this type of tumor is better characterized in adults and in this setting the treatment of choice is surgical resection. However, the place of chemo- and radiotherapy has not been well defined. Here, we present a 9-year-old boy with renal cell carcinoma demonstrating only hematuria without any pathological physical examination findings. The mass was described by abdominal ultrasonography and computed tomography in the left kidney. After the left nephroureterectomy, the patient was given no adjuvant therapy

Aerodynamics in the open channel of the Sistan-type wind-mill with vertical axis wind turbine

International Journal of Numerical Methods for Heat and Fluid FlowThe purpose of this paper is to examine the details of the air mass flow and aerodynamical phenoména across a channel containing a large vertical axis wind turbine. The considered model reproduces as closely as possible the real assembly of the Sistan-type wind-mill whose top is open. The technical results of this work could be used for the restoration and operation of this assembly whose historical and architectural values are recognized.L'objectif de cet article est d’examiner les détails d'un écoulement dans un canal contenant une turbine à axe vertical. Les résultats techniques de ce travail pourront être utilisés pour la restauration et la mise en service de ce dispositif dont la valeur historique et architecturale est reconnue

Diagnostic challenge for ovarian malignant melanoma in premenopausal women: Primary or metastatic?

<p>Abstract</p> <p>Background</p> <p>In the ovary, metastatic malignant melanoma may be confused with primary malignant melanoma and presents a diagnosis challenge. Most cases are associated with disseminated diseases and poor prognosis. We present this case report of a metastatic ovarian malignant melanoma simulating primary ovarian cancer.</p> <p>Case report</p> <p>A 45-year-old premenopausal woman was incidentally found to have an abdominal mass, 3 years after removal of a cutaneous melanoma lesion. Ultrasound and CT scan revealed left two solid masses, which were found to be an ovarian tumor at laparotomy. Left oophorectomy was performed. Histopathology and immunohistochemistry showed melanoma metastasis to the ovary. Nine months later, the patient developed epilepsy and confusion. Magnetic Resonance Imaging showed unique Wright frontal lobe lesion. She underwent stereotactic radio surgery and dacarbazine monotherapy. For months later, the patient is died from disseminate disease progression.</p> <p>Conclusion</p> <p>Ovarian metastasis is an unusual presentation of cutaneous melanoma and the prognosis was dismal. As illustrated by this case report, a differential diagnosis of a metastatic malignant melanoma must be considered.</p

Chemical–Genetic Profiling of Imidazo[1,2-a]pyridines and -Pyrimidines Reveals Target Pathways Conserved between Yeast and Human Cells

Small molecules have been shown to be potent and selective probes to understand cell physiology. Here, we show that imidazo[1,2-a]pyridines and imidazo[1,2-a]pyrimidines compose a class of compounds that target essential, conserved cellular processes. Using validated chemogenomic assays in Saccharomyces cerevisiae, we discovered that two closely related compounds, an imidazo[1,2-a]pyridine and -pyrimidine that differ by a single atom, have distinctly different mechanisms of action in vivo. 2-phenyl-3-nitroso-imidazo[1,2-a]pyridine was toxic to yeast strains with defects in electron transport and mitochondrial functions and caused mitochondrial fragmentation, suggesting that compound 13 acts by disrupting mitochondria. By contrast, 2-phenyl-3-nitroso-imidazo[1,2-a]pyrimidine acted as a DNA poison, causing damage to the nuclear DNA and inducing mutagenesis. We compared compound 15 to known chemotherapeutics and found resistance required intact DNA repair pathways. Thus, subtle changes in the structure of imidazo-pyridines and -pyrimidines dramatically alter both the intracellular targeting of these compounds and their effects in vivo. Of particular interest, these different modes of action were evident in experiments on human cells, suggesting that chemical–genetic profiles obtained in yeast are recapitulated in cultured cells, indicating that our observations in yeast can: (1) be leveraged to determine mechanism of action in mammalian cells and (2) suggest novel structure–activity relationships