Evidence foe superradiance in the recombination from CdTe

Linewidth narrowing attributed to superradiance has been observed in near bandgap radiation due to the recombination of impact ionized carriers in n-type CdTe at room temperature. The light emission was associated with a current breakdown that occurred at a threshold field of 12,000 V/cm in highly compensated n-type samples

Evolution récente de la population, de l’occupation des sols et de la diversité floristique sur un terroir agricole du Sud-Ouest du Niger

Au cours des 50 dernières années, un fort accroissement de la population a été enregistré dans la partie Sud-Ouest du Niger. Ce phénomène a entraîné de profonds changements dans l’occupation des sols et une pression accrue sur les ressources naturelles qui ont eu une incidence importante sur l’allure de la végétation. L’objectif de cette étude est de faire le point sur la richesse spécifique du terroir au regard de cette évolution. Les résultats montrent que la richesse floristique est assez élevée à Ticko. Ainsi, 400 espèces, réparties entre 66 familles ont été recensées. Parmi celles-ci, on compte 85 espèces ligneuses regroupées en 32 familles et 315 espèces herbacées, ou ligneuses basses, réparties entre 44 familles, dont 64% de Thérophytes. Cette flore représente 65% des espèces et 71% des familles présentes dans la région du Liptako. Après 25 ans de forte croissance démographique à Ticko, la diversité floristique reste encore à peu près intacte dans ce terroir. On note cependant une régression des populations d’espèces herbacées et ligneuses, autrefois bien représentées sur le terroir, qui pourrait conduire dans les années à venir à la disparition de ces taxons, et plus particulièrement d’une vingtaine de taxons ligneux.Mots clés : population humaine, diversité floristique, Ticko, Niger

Identification des risques climatiques de la culture du maïs au Burkina Faso

Au Burkina Faso, le maïs est cultivé dans les zones soudaniennes et soudano-sahéliennes où les conditions pluviométriques sont plus favorables. La culture est sensible aux aléas climatiques liés à la variabilité et aux extrêmes pluviométriques. L’objectif de l’étude est d’identifier les risques climatiques pour la culture du maïs. A partir des données météorologiques journalières, une analyse agroclimatique a été réalisée sur la période 1979-2008 sur six stations synoptiques. A l’aide du logiciel Instat+ v 3.036, la variabilité des précipitations et des paramètres clés de la saison agricole dont les dates de démarrage, de fin, la longueur de la saison, les occurrences de séquences sèches et la satisfaction des besoins en eau ont été analysés en termes de risques d’apparition. Les résultats ont montré que le maïs est confronté à deux risques agroclimatiques majeurs. Il s’agit, dans la zone soudano-sahélienne, des déficits hydriques imputables à des séquences sèches au cours du développement du maïs. Tandis que les excès d’eau liés à des fortes pluies ou des successions d’épisodes secs et d’excès d’eau constituent les risques en zone soudanienne. La période d’installation, le cumul pluviométrique, la longueur de la saison ne semblent pas constituer de risques agroclimatiques majeurs pour le maïs.Keywords: Maïs pluvial, variabilité pluviométrique, paramètres saison agricole, déficit hydrique, excès d’ea

Determination of some significant batch culture conditions affecting acetyl-xylan esterase production by Penicillium notatum NRRL-1249

<p>Abstract</p> <p>Background</p> <p>Acetyl-xylan esterase (AXE, <it>EC 3.1.1.72</it>) hydrolyses acetate group from the linear chain of xylopyranose residues bound by β-1,4-linkage. The enzyme finds commercial applications in bio-bleaching of wood pulp, treating animal feed to increase digestibility, processing food to increase clarification and converting lignocellulosics to feedstock and fuel. In the present study, we report on the production of an extracellular AXE from <it>Penicillium notatum </it>NRRL-1249 by solid state fermentation (SSF).</p> <p>Results</p> <p>Wheat bran at a level of 10 g (with 4 cm bed height) was optimized as the basal substrate for AXE production. An increase in enzyme activity was observed when 7.5 ml of mineral salt solution (MSS) containing 0.1% KH₂PO₄, 0.05% KCl, 0.05% MgSO₄.7H₂O, 0.3% NaNO₃, 0.001% FeSO₄.2H₂O and 0.1% (v/w) Tween-80 as an initial moisture content was used. Various nitrogen sources including ammonium sulphate, urea, peptone and yeast extract were compared for enzyme production. Maximal enzyme activity of 760 U/g was accomplished which was found to be highly significant (p ≤ 0.05). A noticeable enhancement in enzyme activity was observed when the process parameters including incubation period (48 h), initial pH (5), 0.2% (w/w) urea as nitrogen source and 0.5% (v/w) Tween-80 as a stimulator were further optimized using a 2-factorial Plackett-Burman design.</p> <p>Conclusion</p> <p>From the results it is clear that an overall improvement of more than 35% in terms of net enzyme activity was achieved compared to previously reported studies. This is perhaps the first report dealing with the use of <it>P. notatum </it>for AXE production under batch culture SSF. The Plackett-Burman model terms were found highly significant (<it>HS</it>), suggesting the potential commercial utility of the culture used (df = 3, LSD = 0.126).</p

Biaya Kualitas Sebagai Usaha Perbaikan Kualitas Proses Produksi Dalam Rangka Mengurangi Produk Cacat

Manajemen produksi sebagai salah satu elemen penting dalam system manajemen Perusahaan, dengan kualitas proses produksi sebagai aspek penting yang ada didalamnya, memberikan andil cukup besar dalam kompetisi Perusahaan pada era persaingan yang semakin ketat. Dengan perencanaan proses produksi yang baik, ternyata jumlah produk cacat yang terjadi tidak mengalami penurunan yang signifikan. Hal ini terlihat dari hasil pengukuran kualitas proses yang dilakukan dengan menggunakan bantuan peta kendali jenis p dengan tingkat penolakan produksi sebagai variabel penelitian. Biaya kualitas yang merupakan indikator tak langsung dari kualitas proses merupakan variable penelitian lainnya yang diteliti. Selanjutnya digunakan diagram pareto untuk menganalisa kelompok biaya yang dominan, aktivitas yang dominan dan pengendalian kualitas (QC) yang menghasilkan biaya dominan. Berdasarkan hasil analisa Pareto dan Peta Kendali, maka dapat diindentifikasi faktor-faktor yang mempengaruhi kualitas proses produksi serta berpotensi menghasilkan biaya kualitas yang dominant, dengan menggunakan Diagram Tulang Ikan. Mengacu pada hasil identifikasi tersebut kemudian direkomendasikan beberapa usulan perbaikan sebagai bahan pertimbangan untuk meningkatkan kualitas proses produksinya. Katakunci: kualitas proses produksi, peta kendali, biaya kualitas, diagram pareto, diagram tulang ika

Management and Complications of Arnold Chiari Hydrocephalus at Tertiary Health Care Center

Objective:&nbsp;to investigate the role of CT and MRI in diagnosis of Arnold chiari malformation of hydrocephalus and its treatment with VP shunt along with complications. Study Design:&nbsp;Prospective study Place and duration:&nbsp;Department of Neurosurgery, DG Khan Medical College from May 4, 2018 to May 4, 2019. Methodology:&nbsp;Fifty patients of congenital hydrocephalus who were not treated previously were selected. Detailed history about disease and clinical examination of patients was performed. Follow ups were done at neurosurgery OPD. SPSS software for data analysis was used and mean ± SD, frequency and percentages were calculated for variables. P value ≤0.05 was considered as significant. Results:&nbsp;Treatment in case of congenital hydrocephalus as VP shunt, intra-aneurysmal coiling, excision of meningomyelocele with VP shunt and suboccipital craniectomy + upper cervical laminectomy (scucl) were observed as 10%, 6%, 8% and 8% respectively.&nbsp; Twelve percent of patients were not treated. Conclusion:&nbsp;CT and MRI are the main diagnostic tools for diagnosis of Arnold chiari malformation and VP shunt is the treatment of choice. Among complications of VP shunt infection of shunt and shunt block are the main complications

The phonology of Lukundu (Bakundu)

PN6519.B26, ISO 639-3 : bdu, Bakundu-Balue language, Bakundu dialec

Psychological Burnout and Coping Strategies of Special Education Teachers in the State of Kuwait

This study aimed at investigating the levels of burnout experienced by special education teachers in the State of Kuwait. It also explored the most common coping strategies they adopt to prevent themselves form teacher burnout. The psychometric sample of the study consists of (60) teachers of children with learning disabilities evenly distributed; (30) male teachers and (30) female teachers with mean age (38.85)  and standard deviation (1. 28) years. The basic sample of the study consists of (108) of teachers of children with learning disabilities in order to make sure of the validity, reliability and the psychometric efficacy of scales used in the study and to validate the correlational hypotheses of the study. This sample consists of (54) male trainers, (54) female trainers with age mean (38.70) and standard deviation (1.33) years. Two main Instruments were used in the study; Psychological Burnout scale and Scale of Coping Strategies. Results showed that male teachers are more sensitive to sag feeling and lack of accomplishment motivation that their female counterparts. Also, female special education teachers are more sensitive to physical symptoms, emotional catharsis, weak work relations and the total score of the scale may be due to the overwhelming work and their social context. Female teachers are overwhelmed with pressing feelings and burdens making them subjected to psychological burnout compared with their male counterparts. Therefore, much effort should be exerted to help female teachers to overcome sources of burnout to lead sound life and to be able to endure work burdens. In addition, Results revealed that female teachers are higher than their male counterparts in their feelings with suppression of contradicting ideas and activities, seeking emotional support, planning for coping compressing situations and emotional catharsis. Positive teacher interaction is a result of school administrators and parents praise of his work inside the class and results he/she achieves. Key words: Psychological Burnout- Coping Strategies- Special Education

Real space information from fluctuation electron microscopy: applications to amorphous silicon

Ideal models of complex materials must satisfy all available information about the system. Generally, this information consists of experimental data, information implicit to sophisticated interatomic interactions and potentially other a priori information. By jointly imposing first-principles or tightbinding information in conjunction with experimental data, we have developed a method: experimentally constrained molecular relaxation (ECMR) that uses all of the information available. We apply the method to model medium range order in amorphous silicon using fluctuation electron microscopy (FEM) data as experimental information. The paracrystalline model of medium range order is examined, and a new model based on voids in amorphous silicon is proposed. Our work suggests that films of amorphous silicon showing medium range order (in FEM experiments) can be accurately represented by a continuous random network model with inhomogeneities consisting of ordered grains and voids dispersed in the network. (Some figures in this article are in colour only in the electronic version) 1

NEURAL NETWORKING OF INFILLED RC LOW-RISE SERVICE BUILDINGS

Artificial neural networks (ANNs) are one of the most research areas that attracts the attention of experts of various scientific areas. Recent research activities regarding ANNs indicated that this method is a powerful tool to solve complicated problems in engineering fields.In this paper, ANNs were utilized to predict the lateral behavior of school buildings in Egypt. For this, reinforced concrete (RC) frames representing common school buildings with different characteristics were analyzed using nonlinear dynamic pushover analysis to obtain their capacity curves, failure loads and displacements. Parameters included number of stories, location and dimensions of the frames, distribution of masonry infill panels, and properties of concrete and reinforcement. Obtained data were used to train several ANN models with different topologies and learning algorithms. The most representative ANN was used to obtain more insight into the behavior of school building frames with different parameters