Archives-June... 

An experimental and numerical study of the operation of an adsorption solar refrigerator using the zeolite-water couple is presented. The experimental consists of measuring the solar radiation incident on the collector-absorber, the temperature of the collector-adsorber, of the condenser and the one of the evaporator. The numerical part concerns a modeling and a simulation of the functioning of this refrigeration system. Transfer equations are deduced from thermal and mass balances established at each component of the refrigerator. The Dubinin-Astakhov equation is adopted for the adsorption kinetics of the zeolite-water pair. The results are presented by the evolution over time of the temperatures of the components of the solar refrigerator (absorbent plate, condenser, evaporator, etc.), as well as the pressure adsorbed, adsorbate mass and SCOP.

The lack of devices to test the tiles is not a reason to ignore the problems related to their durability. This article presents the results of an analysis of the impact behaviour of three qualities of tiles. The strike force of a TFM is 70% lower than that of a TMV and 54% lower than that of a TAC tile. Deflection results (TFM = 1.24 mm; TMV = 0.56 mm and TAC = 0.68 mm), stresses and deformations show that TFM resists better because it deforms extensively before breaking.

This paper motivated by an interdisciplinary research work approach integrating multi-sensory cognitive learning theory with interesting issue of tutoring quality improvement. It is worthy to note that adopted approach has been inspired by analysis and evaluation of phonics methodology applied in teaching children "how to read?". Herein, quantitative evaluation of this issue performed by considering two computer aided learning (CAL) packages concerned with a specific mathematical topic namely long division process. Via realistic modeling of packages using Artificial Neural Networks (ANNs) based upon associative memory learning paradigm. In more details, at educational field practice ; both CAL packages have been applied for teaching children algorithmic steps performing long division processes. Moreover, learning performance evaluation of presented packages considers children outcomes' achievement after tutoring for suggested Mathematical Topic either with or without associated tutor's voice. Interestingly, statistical analysis of obtained educational case study results at children classrooms (for both applied packages) versus classical tutoring proved to be in well agreement with obtained after ANNs computer simulation results.

Forty two samples each of two fish species, Tillapia zilli and Chrysichthys nigrodigitatus were collected along the Kpando Torkor Lake in the Volta Region of Ghana. The samples were investigated for levels of organochlorine pesticide residues and their potential health risks to humans were also assessed. Composite sample of muscles and gills of each species were homogenized using a warring blender. The homogenized samples were Soxhlet extracted with hexane/dichloromethane mixture. The extracts were cleaned up on florisil adsorbent and analyzed for organochlorine pesticide residues using gas chromatography equipped with electron capture detector. In all, fifteen organochlorine pesticides (OCPs) were investigated of which thirteen organochlorines namely, ?-HCH, ?-HCH, p,p'-DDT, p,p'-DDD, p,p'-DDE, heptachlor, aldrin, dieldrin, ?-chordane, ?-endosulfan, ?-endosulfan, endosulfan sulfate and methoxychlor were identified. Heptachlor, ?-HCH, p,p'-DDD, ?-HCH, methoxychlor and endosulfan sulphate were the predominant OCP residues measured. The mean residue concentration in muscles and gills ranges from 0.10 to 17.35 ng/g wet weight and 0.56 to 37.75 ng/g wet weight respectively. A 100% incidence was recorded for ?-HCH, ?-HCH, p,p'-DDD, heptachlor, endosulfan sulfate in the muscle. In the case of the gills a 100% incidence was also recorded for ?-HCH, ?-HCH, p,p'-DDD, ?-chordane, endosulfan sulfate and methoxychlor. Risk assessment based on estimated daily intake (EDI) showed that values obtained for EDI for each organochlorine were far below the non-cancer and cancer benchmark concentrations. As a result the consumption of these fishes will have little or no significant adverse health effects on consumers. It is however, advisable to remove the gills from tilapia fish prior to preparation and consumption to reduce the cumulative and concomitant effect of OCPs in tilapia protein consumers in the long term.

Present study focused on pathological and genetic characterization of predominant post harvest fungal pathogens causing stem end rot, anthracnose and side rots of mango. Aggressiveness of these fungal isolates was tested through artificial inoculations under controlled conditions and all isolates were proved pathogenic with varying degree of aggressiveness in reference to control on both Sindhri and White Chounsa variety with exception of Colletotrichum gloeosporioides which showed no disease symptoms and characterized as non-aggressive isolates. All pathological results were proved highly significant at P<0.05 through ANOVA. DNA of fungal pathogens was successfully extracted and amplification was done through ITS1 and ITS4 primers and the amplified amplicons were productively digested with restriction enzymes (MboI, AluI, EcoRI, HaeIII, TaqI). Good genetic variability was obtained among the isolates of Lasiodiplodia theobromae, Aspergillus niger and Aspergillus flavus but Colletotrichum gloeosporioides did not show genetic variability.

Wire electrical discharge machining (WEDM) own benefit in manufacturing of modern materials, particularly used in the space engineering technology as well as in therapeutic industries. With WEDM advancement, complex components can be able to cut easily those hard to machine with conventional process. Obtained high level of precision component and fine surface finish leads WEDM important, WEDM so perplexing in characteristic, as a result choice of fitting information variables is unrealistic by experimentation process. In any machining process, the machining parameters fundamentally influence quality; cost, time and production rate of a manufactured product. WEDM methodology includes more number of variables that influence its execution. However, in the illumination of the writing study and based on the previous tests, pulse on time, pulse off time, wire pressure, and water pressure are considered for the investigation. In this study, Response Surface Methodology (RSM) is utilized to show relation between the information and yield reactions by using trial information, gathered based on DOE. MRR and Ra were plotted and examined based on impact of information process parameters. Later on the created design can be used for optimization.

The massive amounts of data collected today by software in fields varying from academia to business and many other fields, is increasingly becoming a huge problem due to storage technologies not advancing fast enough to provide the performance scalability needed. This is even truer for data which are highly organized and require analysis while being stored in databases and being accessed by various applications simultaneously. As database vendors struggle to gain more market share new technologies emerge attempting to overcome the disadvantages of previous designs while providing more features. Two popular database types, the Relational Database Management Systems and NoSQL databases are examined. The aim of this paper was to examine and compare two databases from these two database models and answer the question of whether one performs and scales better than the other.

Persistent left superior vena cava (PLSVC) is a rare and benign congenital malformation. It results when the left superior cardinal vein caudal to the innominate vein fails to regress. It is often asymptomatic and usually diagnosed incidentally while performing imaging. The notation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. We report a rare case of a 56 year-old lady in whom we discover this anomaly because of dyspnea.

The present study deals with the comparative study of the quality requirements for the drugs that are injected into the body; during their production and for finished drugs. The concept of total quality control test refers to the process of striving to produce a quality product by a series of measures, requiring an organized effort in order to eliminate errors at every stage in the production. Product testing during the production is done in order to check the conformance of the final product with the standards as specified in the official book of drugs (pharmacopoeias) specific to each country. The test parameters have been discussed and taken from the official book of drugs issued by the respective authorities for India, US and UK. However, the parameters and standards differ from each other to some extent. Hence, an attempt is made to bring out the harmonized standards for a product so that it satisfies the quality requirements for many regions. The parameters as per the standards were compared and certain similarities and differences were observed. It was noted that except for a few parameters, the quality control tests were broadly similar.

Plantain banana are staple crops in DR Congo. These are superficially rooted monocot plants that require a continuous nutrient enrichment mechanism to maintain production, which decreases considerably after a few crop cycles. In burn agriculture, significant nutrient losses are recorded by various mechanisms. This research shows that cropping plantain banana in association with trees makes it possible to increase more not only the production of these on the unburned field in association with the trees, but also and above all to improve the yield of plantains in burned field in association with trees unlike burned cropping without the presence of trees where thirds of low yields are recorded.