Showing papers by "University of Jordan published in 2014"

Exome sequencing links corticospinal motor neuron disease to common neurodegenerative disorders.

Abstract: Hereditary spastic paraplegias (HSPs) are neurodegenerative motor neuron diseases characterized by progressive age-dependent loss of corticospinal motor tract function. Although the genetic basis is partly understood, only a fraction of cases can receive a genetic diagnosis, and a global view of HSP is lacking. By using whole-exome sequencing in combination with network analysis, we identified 18 previously unknown putative HSP genes and validated nearly all of these genes functionally or genetically. The pathways highlighted by these mutations link HSP to cellular transport, nucleotide metabolism, and synapse and axon development. Network analysis revealed a host of further candidate genes, of which three were mutated in our cohort. Our analysis links HSP to other neurodegenerative disorders and can facilitate gene discovery and mechanistic understanding of disease.

Breast Implant–Associated Anaplastic Large-Cell Lymphoma: Long-Term Follow-Up of 60 Patients

Abstract: Purpose Breast implant‐associated anaplastic large-cell lymphoma (ALCL) is a recently described clinicopathologic entity that usually presents as an effusion-associated fibrous capsule surrounding an implant. Less frequently, it presents as a mass. The natural history of this disease and long-term outcomes are unknown.

Reflexivity in research: Promoting rigour, reliability and validity in qualitative research

Abstract: Background: The value of qualitative research is increasingly acknowledged in health studies, as well as the demand for employing rigorous strategies. Although the literature recognises that reflexivity is a valuable and rigorous strategy, few studies unravel the practical employment of reflexivity as a strategy for ensuring rigour and quality in qualitative research. Aim: To present a practical example of how reflexivity can be employed as a strategy for ensuring rigour by reviewing 13 narratives from the author's reflexive diary on qualitative research. Methods: Content analysis and narrative analysis were used to approach and analyse data. Findings: Analysis of the posited qualitative research study found five main outcomes of the influence of reflexivity as a strategy to establish criteria of rigour. Conclusions: Further research is needed to show how reflexivity can be employed as a strategy in qualitative research to: i) establish criteria of rigour; ii) monitor the researcher's subjectivity in gene...

The beliefs that underlie autonomy-supportive and controlling teaching: A multinational investigation

Abstract: We investigated the role of three beliefs in predicting teachers’ motivating style toward students—namely, how effective, how normative, and how easy-to-implement autonomy-supportive and controlling teaching were each believed to be. We further examined national collectivism–individualism as a predictor of individual teachers’ motivating style and beliefs about motivating style, as we expected that a collectivistic perspective would tend teachers toward the controlling style and toward positive beliefs about that style. Participants were 815 full-time PreK-12 public school teachers from eight different nations that varied in collectivism–individualism. All three teacher beliefs explained independent and substantial variance in teachers’ self-described motivating styles. Believed effectiveness was a particularly strong predictor of self-described motivating style. Collectivism–individualism predicted which teachers were most likely to self-describe a controlling motivating style, and a mediation analysis showed that teachers in collectivistic nations self-described a controlling style because they believed it to be culturally normative classroom practice. These findings enhance the literature on the antecedents of teachers’ motivating styles by showing that teacher beliefs strongly predict motivating style, and that culture informs one of these beliefs—namely, normalcy.

A review of the literature regarding stress among nursing students during their clinical education

Abstract: Background: There has been increased attention in the literature about stress among nursing students. It has been evident that clinical education is the most stressful experience for nursing students. Aim: The aim of this paper was to critically review studies related to degrees of stress and the type of stressors that can be found among undergraduate nursing students during their clinical education. Methods: The search strategy involved the utilization of the following databases: MEDLINE (Medical Literature on-Line), CINAHL (Cumulative Index to Nursing and Allied Health Literature), PsycINFO (Psychology Information) and PubMed. Keywords were stress, undergraduate nursing students, clinical practice. The review included those studies published between 2002 and 2013, conducted in any country as long as reported in English, and including a focus on the clinical practice experience of nursing students. Thirteen studies met the eligibility criteria. Results: Four themes were identified: initial clinical experience, comparison between different academic years, cross-cultural comparison, and eustress aspects of clinical experience. Implications for nursing and health policy: This review expands current knowledge in the area of stress in clinical settings and calls for further research. Nursing teachers should utilize the findings of this review to direct their students during clinical practice. Moreover, hospital administrators need to promote policies to promote a training environment where students are supported and inspired.

High-Fidelity Simulation Effects on CPR Knowledge, Skills, Acquisition, and Retention in Nursing Students

Abstract: high-fidelity simulator, cardiopulmonary resuscitation, acquisition and retention, knowledge and skills ABSTRACT Background: There is a gap in the literature regarding learning outcomes linked to the use of high-fidelity simulators compared to that of traditional teaching methods. Aim: To examine the effect of using high-fidelity simulators on knowledge and skills acquisition and retention with university students. Methods: A randomized two-arm trial using two different educational approaches on 90 nursing students assigned randomly to two groups was used at two points of time. Findings: The results showed significant differences in favor of the participants in the high- fidelity simulator group on both the acquisition and retention of knowledge and skills over time. However, a significant loss of cardiopulmonary resuscitation knowledge and skills occurred at 3 months after training in both groups. Conclusions: The findings of this study may assist educators in integrating high-fidelity simula- tors in education and training. In addition, the findings may help nursing educators to arrange additional cardiopulmonary resuscitation training sessions in order to improve cardiac arrested patients' outcomes. Linking Evidence to Action: High-fidelity simulation (HFS) provides students with interactive learning experiences in a safe controlled environment. HFS enables teachers to implement critical clinicalscenarios,suchascardiacarrest,withoutrisktopatients.Integratingthesimulationtraining into nursing curricula will help to overcome the challenges that face many courses, specifically the shortage of clinical areas for training and the increase in numbers of nursing students.

Arylamine N-acetyltransferases: from drug metabolism and pharmacogenetics to drug discovery.

Abstract: Arylamine N-acetyltransferases (NATs) are polymorphic drug-metabolizing enzymes, acetylating arylamine carcinogens and drugs including hydralazine and sulphonamides. The slow NAT phenotype increases susceptibility to hydralazine and isoniazid toxicity and to occupational bladder cancer. The two polymorphic human NAT loci show linkage disequilibrium. All mammalian Nat genes have an intronless open reading frame and non-coding exons. The human gene products NAT1 and NAT2 have distinct substrate specificities: NAT2 acetylates hydralazine and human NAT1 acetylates p-aminosalicylate (p-AS) and the folate catabolite para-aminobenzoylglutamate (p-abaglu). Human NAT2 is mainly in liver and gut. Human NAT1 and its murine homologue are in many adult tissues and in early embryos. Human NAT1 is strongly expressed in oestrogen receptor-positive breast cancer and may contribute to folate and acetyl CoA homeostasis. NAT enzymes act through a catalytic triad of Cys, His and Asp with the architecture of the active site-modulating specificity. Polymorphisms may cause unfolded protein. The C-terminus helps bind acetyl CoA and differs among NATs including prokaryotic homologues. NAT in Salmonella typhimurium supports carcinogen activation and NAT in mycobacteria metabolizes isoniazid with polymorphism a minor factor in isoniazid resistance. Importantly, nat is in a gene cluster essential for Mycobacterium tuberculosis survival inside macrophages. NAT inhibitors are a starting point for novel anti-tuberculosis drugs. Human NAT1-specific inhibitors may act in biomarker detection in breast cancer and in cancer therapy. NAT inhibitors for co-administration with 5-aminosalicylate (5-AS) in inflammatory bowel disease has prompted ongoing investigations of azoreductases in gut bacteria which release 5-AS from prodrugs including balsalazide.

Optimization Solution of Troesch’s and Bratu’s Problems of Ordinary Type Using Novel Continuous Genetic Algorithm

Abstract: A new kind of optimization technique, namely, continuous genetic algorithm, is presented in this paper for numerically approximating the solutions of Troesch’s and Bratu’s problems. The underlying idea of the method is to convert the two differential problems into discrete versions by replacing each of the second derivatives by an appropriate difference quotient approximation. The new method has the following characteristics. First, it should not resort to more advanced mathematical tools; that is, the algorithm should be simple to understand and implement and should be thus easily accepted in the mathematical and physical application fields. Second, the algorithm is of global nature in terms of the solutions obtained as well as its ability to solve other mathematical and physical problems. Third, the proposed methodology has an implicit parallel nature which points to its implementation on parallel machines. The algorithm is tested on different versions of Troesch’s and Bratu’s problems. Experimental results show that the proposed algorithm is effective, straightforward, and simple.

Learning in the Model Space for Cognitive Fault Diagnosis

Abstract: The emergence of large sensor networks has facilitated the collection of large amounts of real-time data to monitor and control complex engineering systems. However, in many cases the collected data may be incomplete or inconsistent, while the underlying environment may be time-varying or unformulated. In this paper, we develop an innovative cognitive fault diagnosis framework that tackles the above challenges. This framework investigates fault diagnosis in the model space instead of the signal space. Learning in the model space is implemented by fitting a series of models using a series of signal segments selected with a sliding window. By investigating the learning techniques in the fitted model space, faulty models can be discriminated from healthy models using a one-class learning algorithm. The framework enables us to construct a fault library when unknown faults occur, which can be regarded as cognitive fault isolation. This paper also theoretically investigates how to measure the pairwise distance between two models in the model space and incorporates the model distance into the learning algorithm in the model space. The results on three benchmark applications and one simulated model for the Barcelona water distribution network confirm the effectiveness of the proposed framework.

Senescent cancer-associated fibroblasts secrete active MMP-2 that promotes keratinocyte dis-cohesion and invasion

Abstract: Previous studies have demonstrated that senescent cancer-associated fibroblasts (CAFs) derived from genetically unstable oral squamous cell carcinomas (GU-OSCC), unlike non-senescent CAFs from genetically stable carcinomas (GS-OSCC), promoted keratinocyte invasion in vitro in a paracrine manner. The mechanism by which this occurs is unclear. Previous work to characterise the senescent-associated secretory phenotype (SASP) has used antibody arrays, technology that is limited by the availability of suitable antibodies. To extend this work in an unbiased manner, we used 2D gel electrophoresis and mass spectroscopy for protein identification. Matrix metalloproteinases (MMPs) were investigated by gelatin zymography and western blotting. Neutralising antibodies were used to block key molecules in the functional assays of keratinocyte adhesion and invasion. Among a variety of proteins that were differentially expressed between CAFs from GU-OSCC and GS-OSCC, MMP-2 was a major constituent of senescent CAF-CM derived from GU-OSCC. The presence of active MMP-2 was confirmed by gelatine zymography. MMP-2 derived from senescent CAF-CM induced keratinocyte dis-cohesion and epithelial invasion into collagen gels in a TGF-β-dependent manner. Senescent CAFs from GU-OSCC promote a more aggressive oral cancer phenotype by production of active MMP-2, disruption of epithelial adhesion and induction of keratinocyte invasion.

Development and applications of porous tantalum trabecular metal-enhanced titanium dental implants.

Abstract: It is estimated that over 26% of people, ages 65–74 in the US are edentulous.1 The number of edentulous people and people with significant number of missing teeth is even worse in the developing world. It is known that edentulism is a comorbidity to several systemic and oral diseases such as osteoporosis, hypertension, atherosclerosis, diabetes, cancer, etc. 2–7 However, the underlying molecular mechanism that may lead an edentulous individual to be at risk for these diseases is not known. Several biological changes occur after loss of natural teeth. These include reduction on masticatory efficiency, altered neuronal/physiolocal sensation, psycological effects, alveolar bone remodeling, and changes on microflora composition. Complete and partial edentulism clearly reduces mechanical chewing function and esthetics. Edentulism and its comobidities have a bidirectional relationship, in other words, each condition worsens the other. While current treatment modalities for edentulism, such as dental implant therapy, are aimed at improving function and esthetics for patients, the systemic and oral co-morbidities of edentulism, including diabetes, osteoporosis, as well as a lack of sufficient remaining alveolar bone, challenge the immediate and long-term success of dental implant therapy. Recently there has been an incorporation of porous tantalum metal into titanium dental implants. This new type of dental implant may improve dental implant therapy in certain populations. This article therefore aims to review the basic science development, advantages and cautions, as well as possible clinical applications of the new tantalum metal implants.

The Trabecular Meshwork: A Basic Review of Form and Function.

Abstract: Glaucoma accounts for around 25% of new blindness in developed countries [3,7]. Primary open-angle glaucoma (POAG) is the most common form and constitutes up to 85% of diagnosed cases. The risk factors include elevated IOP, age, genetic factors, race, thin corneas and abnormal optic nerve anatomy [7]. Glaucoma is normally asymptomatic and is usually not detected until significant irreversible vision loss, which is primarily peripherally located in the field of view, has taken place. The therapeutic management of glaucoma costs the United States and the United Kingdom about 2.5 billion and 216 million USD annually respectively [8,9].

Perceived stress and coping strategies among Jordanian nursing students during clinical practice in psychiatric/mental health courses

Abstract: Clinical practice in the psychiatric/mental health nursing (PMHN) field is considered a highly-stressful experience for nursing students. The purpose of the present study was to identify the degrees of stress, the types of stressors, and coping strategies perceived by undergraduate nursing students during their clinical practice in PMHN courses. A descriptive, longitudinal design was used. Sixty-five students registered in PMHN clinical courses were recruited from five Jordanian universities using a systematic random-sampling method. Data collection was conducted in the second semester of the 2012-2013 academic year at two points of time: pre-PMHN clinical training and post-PMHN training. The Basic Information Questionnaire, Perceived Stress Scale, and Coping Behavior Inventory were administered. Students' ages ranged from 20 to 25 years. The findings illustrate that the highest reported types of stressors at both data-collection times were taking care of patients, stress related to teachers and nursing staff, and from assignments and workloads. The most utilized coping strategy at both data-collection times was problem solving. The findings of the present study are useful for clinical educators in identifying nursing students' stressors, easing their learning in the clinical setting, and establishing an efficient PMHN course programme.

The Relationships among Human Resource Management Practices, Organizational Commitment, and Knowledge Management Processes: A Structural Equation Modeling Approach

Abstract: Human resources and knowledge management are considered to be one of the most important factors withinorganizations that help them to achieve a competitive advantage. However, organizations should take care of thehuman factor and increase their commitment within organizations to take advantage of the knowledge withinthem. The purpose of this research is to investigate the relationship between human resources managementpractices and organizational commitment, on the one hand, and their relationship with knowledge managementprocess, on the other hand.Consultancy firms operating in Jordan were used as the main sample of this study. A random sample wasselected where 220 questionnaires were distributed to such firms. Only 207 questionnaires were submitted backwith a response rate of 52%. A theoretical model was proposed and tested using structural equation modeling(SEM). The results of the SEM analysis indicated that human resources practices (recruitment methods, trainingand development, performance appraisals, and reward systems) have a significant influence on organizationalcommitment (affective commitment, continuance commitment, and normative commitment). Finally, the studydid not find a direct relationship between human resource (HR) practices and knowledge management (KM)processes (knowledge acquisition, knowledge distribution, knowledge interpretation, and organizationalmemory). However, causal links were founded between human resource practices and organizationalcommitment, on the one hand, and organizational commitment and knowledge management processes, on theother hand.

Colloidal stability of citrate and mercaptoacetic acid capped gold nanoparticles upon lyophilization: effect of capping ligand attachment and type of cryoprotectants

Abstract: For various applications of gold nanotechnology, long-term nanoparticle stability in solution is a major challenge. Lyophilization (freeze-drying) is a widely used process to convert labile protein and various colloidal systems into powder for improved long-term stability. However, the lyophilization process itself may induce various stresses resulting in nanoparticle aggregation. Despite a plethora of studies evaluating lyophilization of proteins, liposomes, and polymeric nanoparticles, little is known about the stability of gold nanoparticles (GNPs) upon lyophilization. Herein, the effects of lyophilization and freeze-thaw cycles on the stability of two types of GNPs: Citrate-capped GNPs (stabilized via weakly physisorbed citrate ions, Cit-GNPs) and mercaptoacetic acid-capped GNPs (stabilized via strongly chemisorbed mercaptoacetic acid, MAA-GNPs) are investigated. Both types of GNPs have similar core size and effective surface charge as evident from transmission electron microscopy and zeta potential measurements, respectively. Plasmon absorption of GNPs and its dependence on nanoparticle aggregation was employed to follow stability of GNPs in combination with dynamic light scattering analysis. Plasmon peak broadening index (PPBI) is proposed herein for the first time to quantify GNPs aggregation using nonlinear Gaussian fitting of GNPs UV-vis spectra. Our results indicate that Cit-GNPs aggregate irreversibly upon freeze-thaw cycles and lyophilization. In contrast, MAA-GNPs exhibits remarkable stability under the same conditions. Cit-GNPs exhibit no significant aggregation in the presence of cryoprotectants (molecules that are typically used to protect labile ingredients during lyophilization) upon freeze-thaw cycles and lyophilization. The effectiveness of the cyroprotectants evaluated was on the order of trehalose or sucrose > sorbitol > mannitol. The ability of cryoprotectants to prevent GNPs aggregation was dependent on their chemical structure and their ability to interact with the GNPs as assessed with zeta potential analysis.

Do small spores disperse further than large spores

Abstract: In species that disperse by airborne propagules an inverse relationship is often assumed between propagule size and dispersal distance. However, for microscopic spores the evidence for the relationship remains ambiguous. Lagrangian stochastic dispersion models that have been successful in predicting seed dispersal appear to predict similar dispersal for all spore sizes up to -40 microm diameter. However, these models have assumed that spore size affects only the downwards drift of particles due to gravitation and have largely omitted the highly size-sensitive deposition process to surfaces such as forest canopy. On the other hand, they have assumed that spores are certain to deposit when the air parcel carrying them touches the ground. Here, we supplement a Lagrangian stochastic dispersion model with a mechanistic deposition model parameterized by empirical deposition data for 1-10 microm spores. The inclusion of realistic deposition improved the ability of the model to predict empirical data on the dispersal of a wood-decay fungus (aerodynamic spore size 3.8 microm). Our model predicts that the dispersal of 1-10 microm spores is in fact highly sensitive to spore size, with 97-98% of 1 microm spores but only 12-58% of 10-microm spores dispersing beyond 2 km in the simulated range of wind and canopy conditions. Further, excluding the assumption of certain deposition at the ground greatly increased the expected dispersal distances throughout the studied spore size range. Our results suggest that by evolutionary adjustment of spore size, release height and timing of release, fungi and other organisms with microscopic spores can change the expected distribution of dispersal locations markedly. The complex interplay of wind and canopy conditions in determining deposition resulted in some counterintuitive predictions, such as that spores disperse furthest under intermediate wind, providing intriguing hypotheses to be tested empirically in future studies.