Archives-December 

This paper presents realization of semi Gaussian (S-G) shaper circuits for detector readout front ends. The circuits are based on current difference transconductance amplifier (CDTA) and differential difference current conveyor transconductance amplifier (DDCCTA) and can operate in voltage and current mode. The proposed circuits use grounded capacitors and thus make these suitable from integration viewpoint. The theoretical propositions are verified through extensive SPICE simulations using 0.25?m TSMC CMOS technology model parameters. The performance of proposed topologies is compared in terms of total harmonic distortion, power dissipation, dynamic range, signal to noise ratio (SNR) and output noise.

Pyogenic granuloma (PG) is a benign lesion of the oral cavity that presents as a solitary red or purple nodule. The routine treatment option for PG is excisional biopsy although the lesion may recur due to several factors such as residual tissue after excision or persistent etiologic factors. This case report presents a recurrent PG lesion in a 25-year old male with significant recurrence of swelling observed several months after excision. A combination procedure of excision and open flap debridement prevented further recurrence.

This study aims to investigate the relation of playing types of computer games- sports, warship, training and strategic- with self-regulated learning strategies and motivational beliefs among male students of 3rd grade of high school. The methodology of this study is descriptive of correlation type. The samples include 260 students from high schools of different districts of Sabzevar selected by stratified random sampling among different fields of study- basic science, mathematics and liberal arts. To evaluate the self-regulated learning and motivational beliefs strategies, there was used of Motivated Strategies for Learning Questionnaire developed by Pintrich & De-Groot (1990) and for evaluating the computer games, there was used of two factors, including time spent for playing games per week and type of computer games- sports, warship, training and strategic. For data analysis, there was used of descriptive statistics as well as inferential statistics including Pearson Correlation Coefficient and Regression. Results indicated that there is generally no significant relation between time spent for types of PC games- sports, warship, training and strategic, with self-regulated learning and motivational beliefs strategies; while games are studied separately based on their type, there can be seen a significant relation between time spent for training PC games with self-regulated learning and motivational beliefs strategies, while there is no significant relation between time spent for other types of PC games- sports, warship and strategic with self-regulated learning and motivational beliefs strategies.

The preparation of berbamine-loaded chitosan-agarose microspheres was studied. Optimum preparing parameters were determined by orthogonal experiments as follows: ratio of berbamine to chitosan (w/w) is 1:10; percentage of emulsifier (span 80, v/v) is 6%; volume of glutaraldehyde is 2 mL; and reaction temperature is 70°C. Under these optimal conditions, the encapsulation efficiency and loading capacity of microspheres are 84.57% and 8.44%, respectively. The berbamine-loaded microspheres were spherical with smooth surface, uniform size and without aggregation morphology. In vitro release studies showed that berbamine was released from microspheres in a significantly sustained fashion.

The main purpose of this study was to assess the current status of cooperative learning implementation in secondary schools of Harari regional state. Hence, it examined the extent to which stakeholders: mainly teachers, students and school leaders perform their roles with regard to the implementation of cooperative learning. In addition to this, it tried to look at factors affecting the implementation of cooperative learning. To accomplish this purpose, the study employed descriptive survey research design. The study was carried out on 4 secondary schools which were selected through stratified random sampling techniques. Then, a total of 277 individuals were participated in the study. Among them, 70 teachers and 200 students were included in the sample through stratified random sampling technique. Additionally, 4 principals were included through purposive sampling while 3 supervisors were included through available sampling techniques. Questionnaire, semi-structured interview, document analysis and observation checklist were used to collect the necessary data. The analysis of quantitative data was carried out by using percent, mean, standard deviation, and multiple regressions while qualitative data which was obtained through open ended questions, interview, document analysis and observation checklist were analyzed using narration. The result of the study revealed that, the three responsible stakeholders: Namely, students, teachers and principals are sometimes (moderately) performing their roles. Regarding factors affecting the implementation of cooperative learning, the study indicated that, student related, teacher related, classroom related, and support related factors have their own effect on the status of implementing cooperative learning. Besides, the result of multiple regressions showed that, classroom related, student related and support related factors are significant determinants of the overall status of cooperative learning implementation while teacher related factors do not have significant effect on status of cooperative learning implementation. From the results of the finding, it is possible to conclude that, the status of cooperative learning in the study area is moderate due to the indicated factors affecting its implementation. Therefore, it is recommended that, the government in cooperation with universities located in the study area and non-governmental organizations that work to support quality of education need to provide technical support to teachers and school leaders on how to organize students at the time of practicing cooperative learning and managing the practice of cooperative learning in general through the provision of training opportunities. In addition to this, it is better if school leaders in collaboration with teachers work on raising the awareness of students towards the implementation of cooperative learning.

New energy technologies are currently investigated in R&D and promoted in the political arena. Before these technologies enter the market, their environmental superiority over competing options must be asserted based on a life cycle approach. However, when applying the prevailing status-quo Life Cycle Assessment approach to future energy systems, some drawbacks arise. This paper investigates the environmental performance of several future energy systems (carbon capture and storage, micro cogeneration and photovoltaic’s) and describes associated methodological issues and instruments for dealing with the future dimension of these technologies.

The state of any system can be defined completely by four observable properties, namely composition, pressure, volume and temperature. Study of thermodynamical properties of liquids and liquid mixtures play an important role in elucidation of the nature of molecular interactions. Internal pressure (?i) and free volume (Vf.) are the thermo dynamical parameters, which are useful in understanding the intra and inter molecular interactions in polymer solutions[1,2]. The internal pressure is known to be an inverse function of free volume. In the present work, the ultrasonic velocity, density and viscosity measurements have been made for the temperatures 303K, 313 K, 318 K and 323 K and at different concentrations of polyvinylidene fluoride in polar aprotic solvent i.e Dimethylacetamide. The variation of internal pressure and free volume with temperature and concentration has been carried out. The nature of polymer-solvent interaction and the effect of temperature and concentration on the molecular interaction are studied. The internal pressure is found to vary inversely with free volume and the values reveals that the relation ?i Vf x = constant, holds good for the above system.

Agriculture provides a variety of societal functions. Intensive and expanded using of farming land in recent decades has negative effects on ecological factions and stability of their production. Mechanization is one of the main factors of modern agriculture and directly and indirectly is related to sustainable agriculture. In this study, the relationship between mechanization and sustainability of dry farming wheat and dry chickpea farms in the Kuhdasht county of Iran were investigated. Indicators in two categories: direct (energy consumption, soil compaction and air pollution) and indirect (risk of contamination with chemicals) were evaluated. The impact of mechanization indicators on social- economic (employment, job damage and economic performance) were investigated. Although these indicators do not show a complete overview of sustainability farm, for comparison, farm stability and improvement farm sustainability are effective. The results show strong communication between mechanization and the sustainability in dry farming of wheat and chickpea and although mechanization has the positive effects on sustainability but it has negative effects as well. With determining of type and scale of local mechanization, sustainability of production will increase.

A simple and efficient method has been developed for the synthesis of macrocyclic binuclear Schiff base ligand and their transition metal complexes of the type [M₂(L)X]  where M= Ni(II), Cu(II),   X=CH₃COO^? and [M₂(L)].X where M=Ni(II), Cu(II) and VO(II), X=4ClO₄^?, 2SO₄^2?. If the ligand have been synthesized by the condensation of 3,3’-diaminobenzidine with Phthaldehyde and O-phenylenediamine in the ratio 1:4:2. The prepared macrocyclic ligand and their metal complexes were structurally confirmed by analytical and spectral data and the bonding sites are the azomethine nitrogen atoms. The metal complexes exhibit different geometrical arrangements such as square planar and square pyramidal. The ligand and the complexes were evaluated for their antimicrobial activities. The results showed that this skeletal framework exhibit marked potency as antimicrobial agents.

Background: Prodrugs are form of medications in which the drug is given as inactive parent compound, and then activated in the body by various metabolic processes, after administration. The main objective of this study was to assess the awareness about the cardiovascular prodrugs and their interactions among medical practitioners and to assess the relationship between the physicians' awareness, medical professional and years of experience. Method: The study was cross sectional hospital based study, conducted among physicians working in three of Khartoum state hospitals. Data was collected via structure questionnaire. Results: This is study surveyed 196 medical practitioners, 109 (55.6%) were male and 87 (44.4%) were female, mean for the age was 29.04. more than two third (73%) of the medical practitioners knew prodrug. Concomitant prescribing of proton pump inhibitors with Clopidogrel (prodrug) was about half 97 (49%) of total medical practitioners surveyed, followed by Losartan and Metronidazole 81 (41.3%). More than half (51%) of the respondents answered correctly that Enalapril is cardiovascular prodrug. The overall knowledge of prodrugs interaction effect on therapeutic level was very low ranged from (15.85 %- 37.25%). The most frequent prodrug prescribed on daily basis was Statins followed by Clopidogrel. Conclusion: It concluded that awareness regarding prodrug is low among medical practitioners. The awareness and the knowledge of the medical practitioners about prodrug increase with age, and with their professional medical positions.