The chick embryo: Hatching a model for contemporary biomedical research

Animal models play a crucial role in fundamental and medical research. Progress in the fields of drug discovery, regenerative medicine and cancer research among others are heavily dependent on in vivo models to validate in vitro observations, and develop new therapeutic approaches. However, conventional rodent and large animal experiments face ethical, practical and technical issues that limit their usage. The chick embryo represents an accessible and economical in vivo model, which has long been used in developmental biology, gene expression analysis and loss/ gain of function experiments. It is also an established model for tissue/ cell transplantation, and because of its lack of immune system in early development, the chick embryo is increasingly recognised as a model of choice for mammalian biology with new applications for stem cell and cancer research. Here, we review novel applications of the chick embryo model, and discuss future developments of this in vivo model for biomedical research. © 2009 Wiley Periodicals, Inc

A Case for Redundant Arrays of Hybrid Disks (RAHD)

Hybrid Hard Disk Drive was originally concepted by Samsung, which incorporates a Flash memory in a magnetic disk. The combined ultra-high-density benefits of magnetic storage and the low-power and fast read access of NAND technology inspires us to construct Redundant Arrays of Hybrid Disks (RAHD) to offer a possible alternative to today’s Redundant Arrays of Independent Disks (RAIDs) and/or Massive Arrays of Idle Disks (MAIDs). We first design an internal management system (including Energy-Efficient Control) for hybrid disks. Three traces collected from real systems as well as a synthetic trace are then used to evaluate the RAHD arrays. The trace-driven experimental results show: in the high speed mode, a RAHD outplays the purely-magnetic-disk-based RAIDs by a factor of 2.4–4; in the energy-efficient mode, a RAHD4/5 can save up to 89% of energy at little performance degradationPeer reviewe

Path analysis of grain yield with ıts components in durum wheat under drought stress

This experiment was conducted in order to study the path analysis of grain yield with its components in durum wheat under potential and drought stress condition during 2005-2006 cropping season in Agriculture Research Station of Tabriz Islamic Azad University. 49 durum wheat line (6 line from Iran and 43line from other fount) was used for this purpose. Two separate simple lattic design (7 7) with two replications was conducted . In one experiment, the plants were commonly irrigated until physiological but in another experiment drought stress imposed in four different stages including; tillering, stem elongation, anthesis and grain filling. Correlations among traits after combining two experiments was calculated by SPSS software . Harvest index(r =0.849**), plant height(r =0.695**), and number of tiller (r =0.689**) had high correlation with grain yield. Back ward regressions was used for regressing grain yield on its components. Number of seeds per spike (0.432) , length of spike(0.407) and 1000 seed weight (0.385) had the highest direct positive effects on grain yield. Path analysis for 1000 seed weight, number of tillers per plant and number of seeds per spike showed that plant height (0.452), length of spike (0.857), days to flowering (0.345) were the most effective components of traits, respectively. Therefore, traits such as number of seeds per spike, spike length and 1000 seed weight could be used as a suitable indices in irrigated and dry farming conditions for obtaining durum wheat genotypes with high yield

Transient serum exposure regimes to support dual differentiation of human mesenchymal stem cells

Human mesenchymal stem cells (MSCs), which can generate both osteoblasts and chondrocytes, represent an ideal resource for orthopaedic repair using tissue-engineering approaches. One major difficulty for the development of osteochondral constructs using undifferentiated MSCs is that serum is typically used in culture protocols to promote differentiation of the osteogenic component, whereas existing chondrogenic differentiation protocols rely on the use of serum-free conditions. In order to define conditions which could be compatible with both chondrogenic and osteogenic differentiation in a single bioreactor, we have analysed the efficiency of new biphasic differentiation regimes based on transient serum exposure followed by serum-free treatment. MSC differentiation was assessed either in serum-free medium or with a range of transient exposure to serum, and compared to continuous serum-containing treatment. Although osteogenic differentation was not supported in the complete absence of serum, marker expression and extensive mineralization analyses established that 5 days of transient exposure triggered a level of differentiation comparable to that observed when serum was present throughout. This initial phase of serum exposure was further shown to support the successful chondrogenic differentiation of MSCs, comparable to controls maintained in serum-free conditions throughout. This study indicates that a culture based on temporal serum exposure followed by serum-free treatment is compatible with both osteogenic and chondrogenic differentiation of MSCs. These results will allow the development of novel strategies for osteochondral tissue engineering approaches using MSCs for regenerative medicine. © 2012 John Wiley & Sons, Ltd

Differences in the pattern and regulation of mineral deposition in human cell lines of osteogenic and non-osteogenic origin

Bone marrow-derived mesenchymal stem cells (MSCs) are widely used as a cellular model of bone formation, and can mineralize in vitro in response to osteogenic medium (OM). It is unclear, however, whether this property is specific to cells of mesenchymal origin. We analysed the OM response in 3 non-osteogenic lines, HEK293, HeLa and NTera, compared to MSCs. Whereas HEK293 cells failed to respond to OM conditions, the 2 carcinoma-derived lines NTera and HeLa deposited a calcium phosphate mineral comparable to that present in MSC cultures. However, unlike MSCs, HeLa and NTera cultures did so in the absence of dexamethasone. This discrepancy was confirmed, as bone morphogenetic protein inhibition obliterated the OM response in MSCs but not in HeLa or NTera, indicating that these 2 models can deposit mineral through a mechanism independent of established dexamethasone or bone morphogenetic protein signalling. © 2011 S. Karger AG, Basel

Prevalence and Practice of Self-Medication among Female

Background: Self-medication is a prevalent practice among undergraduate nursing students in Saudi Arabia. This undertakes a great significance among nursing students as they are going to be future healthcare practitioners. Purpose: To determine the prevalence and practices of selfmedication among the female nursing students of the University of Tabuk. Methods: A cross-sectional descriptive design using a pre-constructed questionnaire. The respondents were 128 currently enrolled female nursing students through census sampling. Ethical considerations were done in the conduct of the study. Results: The findings revealed a high prevalence of selfmedication with 79.7%. Most of the respondents were 19 years old (27.3%), second and the fourth year, 66 (51.6%) with family income of >8000 SAR per month, 84 (65.6%). Top reason for self-medication is to save time (51%) for the top three upper body diseases such as headache (76.6%), runny nose (37.3%) and dental pain (37.3%); for body diseases were nausea (16.7%) and fever (16.7%) and for Lower body diseases were wounds (25.5%). The commonly used medicines were Analgesic (90.2%), skin ointment (40.2%), cough syrup (23.5%) and the traditional medicines (62%). Brands selection depended on old prescription (37.3%). The main factor for the selection of the drug was the type of traditional (60.8%) due to price and pharmaceutical company. Such medicines for self-medication were obtained from pharmacy shop 89 (87.3.5%) where half (51%) of the respondents read prescription information before self-medicating. Finally, no association was found between the profile and prevalence of self-medication. Self-care is necessary but must be carried out in a safe and responsible actions of self-medicating. Recommendation: The Saudi government must bolster its laws and policies governing Food and drug administration. Though the participants are nursing students, they must be educated with a great emphasis on safe medications and be aware of the side effects, especially those who are not taking pharmacology subject yet as part of the Nursing course

Religious faith and psychosocial adaptation among stroke patients in Kuwait: A mixed method study

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2012 Springer Science+Business Media.Religious faith is central to life for Muslim patients in Kuwait, so it may influence adaptation and rehabilitation. This study explored quantitative associations among religious faith, self-efficacy, and life satisfaction in 40 female stroke patients and explored the influence of religion within stroke rehabilitation through qualitative interviews with 12 health professionals. The quantitative measure of religious faith did not relate to life satisfaction or self-efficacy in stroke patients. However, the health professionals described religious coping as influencing adaptation post-stroke. Fatalistic beliefs were thought to have mixed influences on rehabilitation. Measuring religious faith among Muslims through a standardized scale is debated. The qualitative accounts suggest that religious beliefs need to be acknowledged in stroke rehabilitation in Kuwait

Effective indicators in human capital productivity of urban management organization

Human capital is considered as a strategic resource among the main resources of any organization and an important factor in producing and presenting services to the society. Improving the productivity of human capital is the main cause of the improvement of productivity in organizations. Management of human capital development, focuses on the quantitative models and technics to test the productivity of the entire system. The central goal is to determine common and distinguishable indicators of human capital productivity in two levels of staff (individual) and organization (management). According to the previous researches and available managerial theories, 29 variables were selected for two main indicators in two levels of staff and organization. Due to the complexity of testing the productivity in the urban management organizations and the need to determine the variables, exploratory factor analysis test was randomly distributed and conducted among 350 people from the target society of human capital urban management (Tehran Municipality) during four phases with setting out a questionnaire consisted of 22 items in Likert scale which distributed randomly. Output of first phase supported 19 variables out of 29 first variables. In the next phase, matrix of variables (partial indicators), was formed due to the correlation coefficients and classified and defined according to two main research indicators by variance analysis in which weight of organization index and staff index were calculated 0.623 and 0.597, respectively. Therefore, programing for the improvement according to process cycle for both main indicators and other exploratory indicators was offered

Quality evaluation of digital twins generated based on uav photogrammetry and tls: Bridge case study

In the current modern era of information and technology, emerging remote advancements have been widely established for detailed virtual inspections and assessments of infrastructure assets, especially bridges. These technologies are capable of creating an accurate digital representation of the existing assets, commonly known as the digital twins. Digital twins are suitable alternatives to in-person and on-site based assessments that can provide safer, cheaper, more reliable, and less distributive bridge inspections. In the case of bridge monitoring, Unmanned Aerial Vehicle (UAV) photogrammetry and Terrestrial Laser Scanning (TLS) are among the most common advanced technologies that hold the potential to provide qualitative digital models; however, the research is still lacking a reliable methodology to evaluate the generated point clouds in terms of quality and geometric accuracy for a bridge size case study. Therefore, this paper aims to provide a comprehensive methodology along with a thorough bridge case study to evaluate two digital point clouds developed from an existing Australian heritage bridge via both UAV-based photogrammetry and TLS. In this regard, a range of proposed approaches were employed to compare point clouds in terms of points’ distribution, level of outlier noise, data completeness, surface deviation, and geometric accuracy. The comparative results of this case study not only proved the capability and applicability of the proposed methodology and approaches in evaluating these two voluminous point clouds, but they also exhibited a higher level of point density and more acceptable agreements with as-is measurements in TLS-based point clouds subjected to the implementation of a precise data capture and a 3D reconstruction model