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501.
Droplet-based microfluidics has shown potential in high throughput single cell assays by encapsulating individual cells in water-in-oil emulsions. Ordering cells in a micro-channel is necessary to encapsulate individual cells into droplets further enhancing the assay efficiency. This is typically limited due to the difficulty of preparing high-density cell solutions and maintaining them without cell aggregation in long channels (>5 cm). In this study, we developed a short pinched flow channel (5 mm) to separate cell aggregates and to form a uniform cell distribution in a droplet-generating platform that encapsulated single cells with >55% encapsulation efficiency beating Poisson encapsulation statistics. Using this platform and commercially available Sox substrates (8-hydroxy-5-(N,N-dimethylsulfonamido)-2-methylquinoline), we have demonstrated a high throughput dynamic single cell signaling assay to measure the activity of receptor tyrosine kinases (RTKs) in lung cancer cells triggered by cell surface ligand binding. The phosphorylation of the substrates resulted in fluorescent emission, showing a sigmoidal increase over a 12 h period. The result exhibited a heterogeneous signaling rate in individual cells and showed various levels of drug resistance when treated with the tyrosine kinase inhibitor, gefitinib.  相似文献   
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503.
High blood glucose level, elevated level of liver enzyme, necrosis and shrinkage of islets of Langerhans has been implicated in the pathogenesis of type 2 diabetes. High blood glucose cause oxidative stress, production of free radical as well as elevated SGPT and SGOT level. Both glibenclamide and simvastatin in fixed dose used as antihyperglycemic antidyslipidemic and antioxidative agents for type 2 diabetes treatment. This study therefore aimed to evaluate the antihyperglycemic, antidyslipidemic and antioxidative effect of fixed dose combination of glibenclamide (0.6 mg/70 kg body weight) and simvastatin (5 mg/70 kg body weight) on long term alloxan induced diabetic rats with cardiovascular disease using various diagnostic kits as a parameter of phamacotherapeutic and pharmacological effect. The study was carried out using 96 Swiss Albino male rats weighing about 200–220 g. Combination therapy induced a significant decrease in blood glucose level in alloxan induced diabetic rats, from 33.75 ± 1.65 to 5.80 ± 0.07 mmol/l 2 h after last dose administration, after 4 weeks treatment. In case of dyslipidemic effect, combination therapy reduced total cholesterol (45 %), triglyceride (36 %) and low density lipoprotein-cholesterol (32 %) levels significantly and increased high density lipoprotein-cholesterol level (57 %) in comparison with their respective diabetic control groups. Results of this study showed that combination therapy effectively decreased SGPT (ALAT) (55 %) and SGOT (ASAT) (51 %) in comparison with diabetic control group. It was also observed that catalase and superoxide dismutase enzyme activity was increased by 58 and 91 % respectively in comparison with diabetic control group after 4 weeks treatment with combination of both drugs. In conclusion, these findings of combination therapy (glibenclamide and simvastatin) on alloxan induced diabetes in rats are significantly better than monotherapy using single drug. The results of the present study suggest that, combination of the fixed dose of glibenclamide and simvastatin might be efficacious in patients with diabetic dyslipidemia and increased oxidative stress. Furthermore, this combination therapy offer dosage convenience to the patients and by virtue of its dual mode of action might be a useful addition to the therapeutic armamentarium for patients with diabetic dyslipidemia and oxidative stress.  相似文献   
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505.
In this paper, we design scale-free collaborative protocols for state and regulated state synchronization of homogeneous multi-agent systems (MAS) with arbitrary fast convergence. The protocol design solely depends on the knowledge of the agents’ model and does not require any information about the communication network and the number of agents. Moreover, our protocols can achieve synchronization with any desired convergence rate by simply tuning a design parameter.  相似文献   
506.
Education and Information Technologies - Mobile-learning (M-learning) apps have grown in popularity and demand in recent years and have become a typical occurrence in modern educational systems,...  相似文献   
507.
The purpose of this study is to examine the effects of individual, environmental, training design, and affective reaction factors on training transfer and transfer motivation. To determine the relationship between these factors and their influence on training transfer and to test the model, the researchers collected data from employees in the Malaysian banking sector. Structural equation modeling with Amos 16 was used to test the model and determine the relationship. The study suggested that training stakeholders should manage the training program effectively. Transfer is maximized when trainees have social support, high performance self‐efficacy, and transfer motivation. Stakeholders (e.g., trainers, trainees, supervisors, and peers) are important to the training transfer process, as are learner readiness, trainee reaction, instrumentality, and training retention. This study revealed that perceived content validity and transfer design work together and influence the trainee's performance self‐efficacy. In other words, if trainers want to improve the performance self‐efficacy level of trainees, they need to explain how the trainee can transfer the learned skills at the workplace and make sure the content of the training is similar to the actual job. The main objective of training programs is to align the employee's expertise with organizational goals. Organizations can achieve their desired objectives only when employees transfer the learned skills on the job. Unfortunately, employees often transfer only a small percentage of skills they have learned in training. To effectively manage their training programs, organizations need to identify and focus on the factors that resist effective training transfer.  相似文献   
508.
Research exploring the possible link between quality of argumentation and content knowledge is not straightforward. Some studies suggest a positive relationship (e.g. Dawson & Schibeci in J Biol Educ 38(1):7–12, 2003) while others do not (e.g. Zohar & Nemet in J Res Sci Teach 39:35–62, 2002). This study examined the possible relationship between pre-service science teachers’ (PSTs) lines of argument regarding genetic cloning issues and their knowledge of the related content. In the research, pre-service teachers were divided into groups according to the results of a conceptual understanding test on genetic cloning, and were categorized as high, middle and low achievers. After introducing three socio-scientific scenarios (relating to genetic cloning) with the intention of prompting lines of argumentation, the PSTs then participated in semi-structured interviews with the research team. It was revealed that there is not a significant relationship between the quality of socio-scientific argumentation among PSTs and their knowledge of content in the domain of cloning. Explanations for these results are discussed in light of the related literature and with reference to the interviews.  相似文献   
509.
The Sultanate of Oman is a developing country that has accepted the English language as a significant tool for modernization. This was best interpreted in the opening of Sultan Qaboos University (SQU) in 1986, which has delivered its different academic programmes totally or partially through the English language. One of the colleges of SQU has been the College of Law. It was opened in 1997 to help contribute to effective implementation of nationalisation and national development in the Sultanate of Oman, which English language proficiency is a part and parcel of. However, graduates exiting the College so far have been unable to fulfil this strategic aim due to policy-practice drawbacks. Evident weaknesses in their English language and legal knowledge have provoked repeated complaints from the employers in both sectors. Accordingly, a decision was made to introduce a bilingual programme through which approximately 30 % of the subjects at the College of Law would be taught in English. This study, therefore, researches the uses of English language in the Law job market in the Sultanate of Oman and its implications for policy-practice improvement. A questionnaire was designed and distributed to 182 graduates of the College of Law, SQU. Findings have shown that while the new programme has the potential to serve national development and Omanisation, the College faculties have a pivotal role to play in influencing a positive implementation of the plan.  相似文献   
510.
In an up-linkage replication, three experiments examined adult humans’ folk physics, i.e., their naturally occurring and spontaneous understanding of the physical world, using a violation of expectation (VOE) task and stimuli similar to those used to study chimpanzees’, monkeys’, and rooks’ folk physics. Unlike what has been reported with nonhuman primates, adult humans did not look longer at physically impossible than possible events, though they did rate the physically impossible events as more interesting and novel than the possible events. These results underscore that behavior during a VOE experiment has many possible causes, only one of which may be a subject’s folk physics.  相似文献   
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