Physicochemical characteristics of various milk samples available in Pakistan

We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards.     

Dialogue in the support of learning to teach: a case study of a mentor/mentee pair in a teacher education programme

In this paper, we examine the role of reflection in teacher preparation, specifically within a mentoring relationship between cooperating and preservice teacher. We report findings from a case analysis of this pair who engaged in problem-posing dialogue within pre- and post-conferences around practice over one year of their work together in an elementary-level classroom. The context is an innovative programme in which cooperating teachers pursue their Master’s degree while undergraduates (preservice teachers) complete their elementary education degrees. Our analysis of talk about teaching during six coaching cycles as well as supporting documents illustrates how Jane’s mentoring supported reflective practices and disrupted a notion of a field experience as simply a place to ‘practice’ pedagogical knowledge with corrective feedback. Additionally, we explore the tensions in this approach to mentoring. This case study has implications for teacher educators who seek to bolster teacher preparation through the support of mentoring relationships.     

开放灵活的分布式学习环境

为了帮助设计者创建开放、灵活的分布式E-Learning环境,该文提出了一个E-Learning框架模型,从八个维度列出了E-Learning设计中需要考虑的关键问题:机构,教学,技术,界面设计,评价,管理,资源支持,伦理。     

Towards An Understanding of Muslim American Adolescent High School Experiences

The researchers conducted a grounded theory study to explore the experiences of Muslim American adolescents in high school. Findings indicate that students had to navigate unique challenges because of their religious faith, but those obstacles presented opportunities to confront bias and discrimination. Recommendations for how school counselors can support the development of Muslim American adolescents are presented.     

The spread of private tutoring in English in developing societies: exploring students’ perceptions

ABSTRACT

Although research on private tutoring has gained visibility in recent years, private tutoring in English (PT-E) has not received notable attention. This paper examines students’ perceptions of PT-E in Bangladesh in terms of its necessity and helpfulness, peer pressure in PT-E participation and ethicality of PT-E practice and government intervention. Our analysis of survey data (N?=?572) leads to characterising PT-E and explaining the reasons for its popularity. As a popular learning space beyond formal schooling, PT-E is available in various forms and quality catering to the purchasing power of different social groups. We argue that students may resort to PT-E not because of its proven effectiveness but because of their declining faith in school English teaching. The paper contributes to our understanding of the complex interactions between the curricular (school) and non-curricular (PT-E) settings and family socioeconomic resources in the teaching of English as a globally desired language.     

Analysis and experimental investigation into a finite time current observer based adaptive backstepping control of buck converters

In this paper, the issue of output voltage regulation in buck type dc-dc converters is addressed using a current sensorless control technique. The proposed strategy integrates a finite time current observer with an adaptive backstepping control scheme to yield a cost-effective and robust control mechanism. The overall controller stability in the sense of Lyapunov is proved. Applicability of the proposed control is verified experimentally on a buck converter in the laboratory. The control scheme is implemented on dSPACE DS1103 platform based on DSP TM320F240 processor. To examine the efficacy of the proposed method, the buck converter is subjected to a wide change in input voltage, load resistance and reference voltage. For comparison purpose, a conventional adaptive backstepping control scheme is evaluated under identical conditions of experimental study to examine the merit of the proposed control. The results obtained reveal that the proposed control is prompt in rejecting perturbations and achieves a smooth, reliable and satisfactory output voltage regulation with faithful and time bound estimation of inductor current. Thereby, this investigation demonstrates the validity of the proposed control in maintaining a stringent output voltage regulation in buck converters.     

Probing the mechanical properties of brain cancer cells using a microfluidic cell squeezer device

Despite being invasive within surrounding brain tissues and the central nervous system, little is known about the mechanical properties of brain tumor cells in comparison with benign cells. Here, we present the first measurements of the peak pressure drop due to the passage of benign and cancerous brain cells through confined microchannels in a “microfluidic cell squeezer” device, as well as the elongation, speed, and entry time of the cells in confined channels. We find that cancerous and benign brain cells cannot be differentiated based on speeds or elongation. We have found that the entry time into a narrow constriction is a more sensitive indicator of the differences between malignant and healthy glial cells than pressure drops. Importantly, we also find that brain tumor cells take a longer time to squeeze through a constriction and migrate more slowly than benign cells in two dimensional wound healing assays. Based on these observations, we arrive at the surprising conclusion that the prevailing notion of extraneural cancer cells being more mechanically compliant than benign cells may not apply to brain cancer cells.     

Hematological Parameters and RBC TBARS Level of Q 10 Supplemented Tribal Sickle Cell Patients: A Hospital Based Study

The study has been undertaken as number of sickle cell patients in Chhattisgarh tribal population is 23.7 %. The Co enzyme Q10 is a strong antioxidant and energy producing compound. The patients were divided into three groups group A homozygous (SS), group B heterozygous (AS) and group C controls for TBARS study. The age group is 10–55 years and 200 mg of CoQ10 was given to A and B groups. The hematological parameters, C reactive protein as well as RBC TBARS level were performed by usual and standard techniques. The results were obtained as 25.37 % increased RBC level in group A and 23.24 % in group B. The increased hemoglobin level was observed as 16.73 % in group A and 10.7 % in group B. In case of WBC it was observed increased 24.38 % in group A and 12.0 % in group B. C-reactive protein was observed 7.8 times decreased in group A and 1.54 times in group B. The RBC TBARS level was also found decreased 48 % in group A and 51 % in group B as compared to group C. During the supplementation of coenzyme Q10 the pain caused by vaso-occlusive events has reduced. This significant increase in hematological parameters as well as decreased C-reactive protein and TBARS level suggest that the Q10 should be included in the diet of sickle cell patients.