bluuebunny/crossref_metadata_2025 huggingface dataset:
The Contribution of L-Arginine to the Neurotoxicity of Recombinant Tissue Plasminogen Activator following Cerebral Ischemia: A Review of rtPA Neurotoxicity
Authors: Harston George WJ , Sutherland Brad A , Kennedy James , Buchan Alastair M
Published: August 2010

Alteplase is the only drug licensed for acute ischemic stroke, and in this formulation, the thrombolytic agent recombinant tissue plasminogen activator (rtPA) is stabilized in a solution of L-arginine. Improved functional outcomes after alteplase administration have been shown in clinical trials, along with improved histological and behavioral measures in experimental models of embolic stroke. However, in animal models of mechanically induced ischemia, alteplase can exacerbate ischemic damage. We have systematically reviewed the literature of both rtPA and L-arginine administration in mechanical focal ischemia. The rtPA worsens ischemic damage under certain conditions, whereas L-arginine can have both beneficial and deleterious effects dependent on the time of administration. The interaction between rtPA and L-arginine may be leading to the production of nitric oxide, which can cause direct neurotoxicity, altered cerebral blood flow, and disruption of the neurovascular unit. We suggest that alternative formulations of rtPA, in the absence of L-arginine, would provide new insight into rtPA neurotoxicity, and have the potential to offer more efficacious thrombolytic therapy for ischemic stroke patients.
microRNA‐122 as a regulator of mitochondrial metabolic gene network in hepatocellular carcinoma
Authors: Burchard Julja , Zhang Chunsheng , Liu Angela M , Poon Ronnie T P , Lee Nikki P Y , Wong Kwong‐Fai , Sham Pak C , Lam Brian Y , Ferguson Mark D , Tokiwa George , Smith Ryan , Leeson Brendan , Beard Rebecca , Lamb John R , Lim Lee , Mao Mao , Dai Hongyue , Luk John M
Published: August 2010

Tumorigenesis involves multistep genetic alterations. To elucidate the microRNA (miRNA)–gene interaction network in carcinogenesis, we examined their genome‐wide expression profiles in 96 pairs of tumor/non‐tumor tissues from hepatocellular carcinoma (HCC). Comprehensive analysis of the coordinate expression of miRNAs and mRNAs reveals that miR‐122 is under‐expressed in HCC and that increased expression of miR‐122 seed‐matched genes leads to a loss of mitochondrial metabolic function. Furthermore, the miR‐122 secondary targets, which decrease in expression, are good prognostic markers for HCC. Transcriptome profiling data from additional 180 HCC and 40 liver cirrhotic patients in the same cohort were used to confirm the anti‐correlation of miR‐122 primary and secondary target gene sets. The HCC findings can be recapitulated in mouse liver by silencing miR‐122 with antagomir treatment followed by gene‐expression microarray analysis. In vitro miR‐122 data further provided a direct link between induction of miR‐122‐controlled genes and impairment of mitochondrial metabolism. In conclusion, miR‐122 regulates mitochondrial metabolism and its loss may be detrimental to sustaining critical liver function and contribute to morbidity and mortality of liver cancer patients.
Sequence signatures and mRNA concentration can explain two‐thirds of protein abundance variation in a human cell line
Authors: Vogel Christine , de Sousa Abreu Raquel , Ko Daijin , Le Shu‐Yun , Shapiro Bruce A , Burns Suzanne C , Sandhu Devraj , Boutz Daniel R , Marcotte Edward M , Penalva Luiz O
Published: August 2010

Transcription, mRNA decay, translation and protein degradation are essential processes during eukaryotic gene expression, but their relative global contributions to steady‐state protein concentrations in multi‐cellular eukaryotes are largely unknown. Using measurements of absolute protein and mRNA abundances in cellular lysate from the human Daoy medulloblastoma cell line, we quantitatively evaluate the impact of mRNA concentration and sequence features implicated in translation and protein degradation on protein expression. Sequence features related to translation and protein degradation have an impact similar to that of mRNA abundance, and their combined contribution explains two‐thirds of protein abundance variation. mRNA sequence lengths, amino‐acid properties, upstream open reading frames and secondary structures in the 5′ untranslated region (UTR) were the strongest individual correlates of protein concentrations. In a combined model, characteristics of the coding region and the 3′UTR explained a larger proportion of protein abundance variation than characteristics of the 5′UTR. The absolute protein and mRNA concentration measurements for >1000 human genes described here represent one of the largest datasets currently available, and reveal both general trends and specific examples of post‐transcriptional regulation.
Effect of molecular mass of methoxypoly(ethylene glycol) activated with succinimidyl carbonate on camouflaging pancreatic islets
Authors: Barani Leila , Vasheghani‐Farahani Ebrahim , Lazarjani Hamideh Aghajani , Hashemi‐Najafabadi Sameereh , Atyabi Fatemeh
Published: August 2010

The surface modification of Langerhans islets by grafting activated poly(ethylene glycol) on to their capsules in order to prevent immune‐system stimulation is a novel method in diabetes cell therapy. In the present study, mPEG [methoxypoly(ethylene glycol)] with two molecular masses of 5 and 10 kDa, activated with SC (succinimidyl carbonate), was grafted on to the surface of pancreatic islets at a polymer concentration of 22 mg/ml. It was found that PEGylated islets were viable and active, and no morphological changes on the collagen capsule of islets were observed. The amount of interleukin‐2 secretion from lymphocytes co‐cultured with islets PEGylated with mPEG‐SC of 5 and 10 kDa was 112.12±23.09 pg/ml and 172.75±27.94 pg/ml respectively. Thus mPEG‐SC (SC‐activated mPEG) with higher molecular mass was more suitable for camouflaging islets from the immune system.
Enhancement of the latent 3-isopropylmalate dehydrogenase activity of promiscuous homoisocitrate dehydrogenase by directed evolution
Authors: Suzuki Yumewo , Asada Kuniko , Miyazaki Junichi , Tomita Takeo , Kuzuyama Tomohisa , Nishiyama Makoto
Published: August 2010

HICDH (homoisocitrate dehydrogenase), which is involved in lysine biosynthesis through α-aminoadipate, is a paralogue of IPMDH [3-IPM (3-isopropylmalate) dehydrogenase], which is involved in leucine biosynthesis. TtHICDH (Thermus thermophilus HICDH) can recognize isocitrate, as well as homoisocitrate, as the substrate, and also shows IPMDH activity, although at a considerably decreased rate. In the present study, the promiscuous TtHICDH was evolved into an enzyme showing distinct IPMDH activity by directed evolution using a DNA-shuffling technique. Through five repeats of DNA shuffling/screening, variants that allowed Escherichia coli C600 (leuB−) to grow on a minimal medium in 2 days were obtained. One of the variants LR5–1, with eight amino acid replacements, was found to possess a 65-fold increased kcat/Km value for 3-IPM, compared with TtHICDH. Introduction of a single back-replacement H15Y change caused a further increase in the kcat/Km value and a partial recovery of the decreased thermotolerance of LR5–1. Site-directed mutagenesis revealed that most of the amino acid replacements found in LR5–1 effectively increased IPMDH activity; replacements around the substrate-binding site contributed to the improved recognition for 3-IPM, and other replacements at sites away from the substrate-binding site enhanced the turnover number for the IPMDH reaction. The crystal structure of LR5–1 was determined at 2.4 Å resolution and revealed that helix α4 was displaced in a manner suitable for recognition of the hydrophobic γ-moiety of 3-IPM. On the basis of the crystal structure, possible reasons for enhancement of the turnover number are discussed.
Involvement of c‐Jun N‐terminal kinase and extracellular signal‐regulated kinase 1/2 in EGF‐induced angiogenesis
Authors: Shen Kaikai , Sheng Yuchen , Ji Lili , Wang Zhengtao
Published: August 2010

Angiogenesis is a process during which endothelial cells divide and migrate to form new capillaries from the preexisting blood vessels. The present study was designed to investigate whether MAPKs (mitogen‐activated protein kinases) play crucial roles in regulating EGF (epidermal growth factor)‐induced endothelial cell angiogenesis. Our results showed that EGF stimulated HUVEC (human umbilical vein endothelial cells) proliferation in a concentration‐dependent manner, of which the maximum effective concentration of EGF was 10 ng/ml. Western blot analysis showed that EGF at 10 ng/ml significantly induced the phosphorylation of ERK1/2 (extracellular signal‐regulated kinase 1 and 2) and p38 kinase at 5 min, while it induced the phosphorylation of JNK/SAPK (c‐Jun N‐terminal kinase/stress‐activated protein kinase) at 15 min. Further results showed that a JNK/SAPK inhibitor, SP600125, and a specific siRNA JNK/SAPK could both significantly inhibit EGF‐induced tube formation in HUVEC cells, and an ERK1/2 inhibitor PD098059 could also block the tube formation in some content, while a p38 inhibitor SB203580 failed to do so. Furthermore, only SP600125 significantly inhibited EGF‐induced HUVEC cell proliferation under no cytotoxic concentration, so did JNK/SAPK siRNA. In conclusion, JNK/SAPK and ERK1/2 signals therefore play critical roles in EGF‐mediated HUVEC cell angiogenesis.
Demonstration of a plasma mirror based on a laminar flow water film
Authors: Panasenko Dmitriy , Shu Anthony J. , Gonsalves Anthony , Nakamura Kei , Matlis Nicholas H. , Toth Csaba , Leemans Wim P.
Published: August 2010

A plasma mirror based on a laminar water film with low flow speed (0.5–2 cm/s) has been developed and characterized, for use as an ultrahigh intensity optical reflector. The use of flowing water as a target surface automatically results in each laser pulse seeing a new interaction surface and avoids the need for mechanical scanning of the target surface. In addition, the breakdown of water does not produce contaminating debris that can be deleterious to vacuum chamber conditions and optics, such as is the case when using conventional solid targets. The mirror exhibits 70% reflectivity, while maintaining high-quality of the reflected spot.
X-ray diffuse scattering from threading dislocations in epitaxial GaN layers
Authors: Barchuk M. , Holý V. , Miljević B. , Krause B. , Baumbach T. , Hertkorn J. , Scholz F.
Published: August 2010

In this article, we combine diffuse x-ray scattering with a Monte Carlo simulation method for the determination of the dislocation density in thin heteroepitaxial layers. As a model, we consider GaN epitaxial layers containing threading dislocations perpendicular to the surface. The densities of particular types of threading dislocations following from the comparison of measured and simulated distributions of diffusely scattered x-ray intensity are compared with the dislocation densities determined by etching. A good agreement was found.
Changing vacancy balance in ZnO by tuning synthesis between zinc/oxygen lean conditions
Authors: Venkatachalapathy Vishnukanthan , Galeckas Augustinas , Zubiaga Asier , Tuomisto Filip , Kuznetsov Andrej Yu.
Published: August 2010

The nature of intrinsic defects in ZnO films grown by metal organic vapor phase epitaxy was studied by positron annihilation and photoluminescence spectroscopy techniques. The supply of Zn and O during the film synthesis was varied by applying different growth temperatures (325–485 °C), affecting decomposition of the metal organic precursors. The microscopic identification of vacancy complexes was derived from a systematic variation in the defect balance in accordance with Zn/O supply trends.
Theory of the phonon properties of pure and ion-doped ZnO nanoparticles
Authors: Wesselinowa J. M. , Apostolov A. T.
Published: August 2010

Based on the s-d model including electron–phonon and spin–phonon interaction, and using a Green’s function technique we have studied surface, size, and ion doping effects on the phonon properties of ZnO nanoparticles (NPs). We have shown that the electron–phonon and anharmonic phonon–phonon interactions play an important role in pure ZnO NPs, whereas in the transition metal (TM) and rare earth (RE) doped ZnO NPs the spin–phonon interaction must be taken into account in order to explain the experimental data. Due to surface and size effects, the phonon frequency decreases and the phonon damping increases with decreasing of particle size. By TM ion doping we obtain hardening, whereas by doping with Mn or RE ions-softening of the phonon energy with increasing the dopant concentration. This is due to the different radii of the doping ions compared to the host Zn ion radius and to the induced different lattice strain and spin–phonon interactions. The phonon damping is always enhanced compared to the undoped case. The observed results are in qualitative agreement with the experimental data. Our model and theory can be applied to all pure and doped diluted magnetic semiconductor NPs.
A parameter-free prediction of simulated crystal nucleation times in the Lennard-Jones system: From the steady-state nucleation to the transient time regime
Authors: Peng Lu Jian , Morris James R. , Aga Rachel S.
Published: August 2010

Large scale simulations of crystal nucleation from the liquid are performed using the Lennard-Jones potential to determine the time required for nucleation. By considering both transient and finite-size effects, we for the first time successfully predict the nucleation time without any parameter fitting in the Lennard-Jones system. All necessary parameters are derived from separate, equilibrium simulations. At small undercoolings, large system size effects are observed. The required system size is not only determined by the size of the critical nuclei, but also the characteristic spacing between them. Two distinct nucleation regions are predicted by theory and observed by the simulations, which are dominated by the transient time and the steady-state nucleation time, respectively.
Light-induced point defect reactions of residual iron in crystalline silicon after aluminum gettering
Authors: Abdelbarey D. , Kveder V. , Schröter W. , Seibt M.
Published: August 2010

Deep level transient spectroscopy is used to study light-induced reactions of residual iron impurities after aluminum gettering (AlG) in crystalline silicon. White-light illumination at room temperature leads to the formation of a defect which is associated with a donor level at 0.33 eV above the valence band. This defect is stable up to about 175 °C where it dissociates reversibly in case of small iron concentrations and irreversibly for high iron concentrations. Since marker experiments using gold and platinum diffusion show a high vacancy concentration after AlG a tentative identification of the new defect as the metastable iron-vacancy pair is proposed.
Bulk Cr tips with full spatial magnetic sensitivity for spin-polarized scanning tunneling microscopy
Authors: Schlenhoff A. , Krause S. , Herzog G. , Wiesendanger R.
Published: August 2010

A full magnetic characterization of bulk Cr tips has been achieved using spin-polarized scanning tunneling microscopy at low temperature. A detailed bias-dependent study of the spatial magnetic sensitivity on the system of 1.5 monolayers of Fe/W(110) reveals that all magnetic directions in space are sensed over a wide bias range, thereby indicating a canted magnetization direction being a typical feature of bulk Cr tips. Consequently, using Cr as tip material allows any standard scanning tunneling microscope setup to be extended by the spin-polarized mode.
Studies on electrostatic interactions of colloidal particles in two dimensions: A modeling approach
Authors: Lee Chi-Lun , Ng Sio-Kit
Published: August 2010

We study the effective electrostatic interactions between a pair of charged colloidal particles without salt ions while the system is confined in two dimensions. In particular, we use a simplified model to elucidate the effects of rotational fluctuations in counterion distribution. The results exhibit effective colloidal attractions under appropriate conditions. Meanwhile, long-range repulsions persist over most of our studied cases. The repulsive forces arise from the fact that in two dimensions, the charged colloids cannot be perfectly screened by counterions, as the residual quadrupole moments contribute to the repulsions at longer range. By applying multiple expansions, we find that the attractive forces observed at short range are mainly contributed by electrostatic interactions among higher-order electric moments. We argue that the scenario for attractive interactions discussed in this work is applicable to systems of charged nanoparticles or colloidal solutions with macroions.
Gate controlled magnetoresistance in a silicon metal-oxide-semiconductor field-effect-transistor
Authors: Ciccarelli C. , Park B. G. , Ogawa S. , Ferguson A. J. , Wunderlich J.
Published: August 2010

We present a study of the magnetoresistance (MR) of a Si metal-oxide-semiconductor field-effect-transistor (MOSFET) at the break-down regime when a magnetic field is applied perpendicular to the plane of the device. We have identified two different regimes where we observe a large and gate-voltage dependent MR. We suggest two different mechanisms which can explain the observed high MR. Moreover, we have studied how the MR of the MOSFET scales with the dimensions of the channel for gate voltages below the threshold. We observed a decrease in the MR by two orders of magnitude by reducing the dimensions of the channel from 50×280 μm2 to 5×5 μm2.
Optical properties of surface modified polypropylene by plasma immersion ion implantation technique
Authors: Ahmed Sk. Faruque , Moon Myoung-Woon , Kim Chansoo , Jang Yong-Jun , Han Seonghee , Choi Jin-Young , Park Won-Woong , Lee Kwang-Ryeol
Published: August 2010

The optical band gap and activation energy of polypropylene (PP) induced by an Ar plasma immersion ion implantation technique were studied in detail. It was revealed that the structural alternation with an increase in polymer chain cross-linking in the ion beam affected layer enhanced the optical properties of PP. The optical band gap, calculated from the transmittance spectra, decreased from 3.44 to 2.85 eV with the Ar plasma ion energy from 10 to 50 keV. The activation energy, determined from the band tail of the transmittance spectra, decreased while the electrical conductivity increased with the Ar plasma ion energy.
Magnetically assisted quantum cascade laser emitting from 740 GHz to 1.4 THz
Authors: Scalari Giacomo , Turčinková Dana , Lloyd-Hughes James , Amanti Maria I. , Fischer Milan , Beck Mattias , Faist Jérôme
Published: August 2010

In this paper we show that by applying a perpendicular magnetic field to a quantum cascade structure it is possible to enhance the gain of different optical transitions. The combination of magnetic confinement with a broadband, cutoff-free optical resonator allows the demonstration of laser action over a large bandwidth, from 733 GHz to 1.38 THz together with the emission at 3.2 THz. A different lasing scheme is revealed that does not rely on resonant tunneling as the main injection mechanism. In combination with the magnetically enhanced gain laser emission at 1 THz is observed up to a temperature of 115 K, which corresponds to a ratio kBT/hν=2.3 between the lattice thermal energy and the laser photon energy.
Clustering in polar media
Authors: Hammouda Boualem
Published: August 2010

Clustering prevails in water-soluble polymers and biological macromolecules. It has also been observed in polar solvent mixtures. The possible causes of clustering are discussed. A systematic investigation of clustering in poly(ethylene oxide)/d-water solutions has been undertaken using the small-angle neutron scattering method. The poly(ethylene oxide) monomer is formed of an oxygen atom and an ethylene group. Using the random phase approximation, partial Flory–Huggins interaction parameters for the three pairs (oxygen/d-water, ethylene/d-water, and oxygen/ethylene) are derived. Results show that the first two (oxygen/d-water and ethylene/d-water) are characterized by a lower critical solution temperature phase behavior (whereby phase separation occurs upon heating), while the third one (oxygen/ethylene) is characterized by an upper critical solution temperature phase diagram (whereby phase separation occurs upon cooling). It is argued that clustering is caused by the increasing repulsive interaction between oxygen and ethylene for decreasing temperature and increasing polymer volume fraction. This leads to increasing attractive interactions between ethylene groups that stick together.
The Discursive Construction of Childhood and Youth in AIDS Interventions in Lesotho's Education Sector: Beyond Global — Local Dichotomies
Authors: Ansell Nicola
Published: August 2010

In southern Africa interventions to halt the spread of AIDS and address its social impacts are commonly targeted at young people, in many cases through the education sector. In Lesotho, education-sector responses to AIDS are the product of negotiation between a range of ‘local’ and ‘global’ actors. Although many interventions are put forward as government policy and implemented by teachers in schools, funding is often provided by bilateral and multilateral donors, and the international ‘AIDS industry’—in the form of UN agencies and international NGOs—sets agendas and makes prescriptions. This paper analyses interviews conducted with policy makers and practitioners in Lesotho and a variety of documents, critically examining the discourses of childhood and youth that are mobilised in producing changes in education policy and practice to address AIDS. Focusing on bursary schemes, life-skills education, and rights-based approaches, the paper concludes that, although dominant ‘global’ discourses are readily identified, they are not simply imported wholesale from the West, but rather are transformed through the organisations and personnel involved in designing and implementing interventions. Nonetheless, the connections through which these discourses are made, and children are subjectified, are central to the power dynamics of neoliberal globalisation. Although the representations of childhood and youth produced through the interventions are hybrid products of local and global discourses, the power relations underlying them are such that they, often unintentionally, serve a neoliberal agenda by depicting young people as individuals in need of saving, of developing personal autonomy, or of exercising individual rights.
The Property Transmission Hypothesis: A Possible Explanation for Visual Impressions of Pulling and other Kinds of Phenomenal Causality
Authors: White Peter A
Published: August 2010

Under certain circumstances, stimuli involving two moving objects that do not come into contact reliably give rise to the illusory perceptual impression that one of the objects is pulling the other, as if there is an unseen connection between them. It is proposed that the conditions determining the occurrence of this impression can be explained as cases of application of the property-transmission hypothesis. This is a general hypothesis that causal objects operate in part by transmitting some of their own properties to effect objects under conditions where the causal object is active, where there are cues to the occurrence of generative transmission between the causal object and an effect object, and where there is a time-ordered relation of resemblance between properties of the causal object and those of the effect object. This hypothesis predicts that the pulling impression should occur only when the effect object adopts kinematic properties (speed and direction) that resemble those of the causal object. An experiment is reported that supports this prediction.
Returning to physiotherapy practice: the perspective of returners, potential returners and clinical supervisors
Authors: Sheppard Lorraine , Crowe Michael , Jones Anne , Adams Robyn
Published: August 2010

The experience of returning to physiotherapy practice needs to be understood from the perspective of those who have returned to practice, those thinking of returning, and clinical supervisors who have worked with people that have returned to practice. A qualitative methodology using an interpretivist theoretical framework was utilised. Participants were selected using a combination of purposive and snowballing sampling techniques. Semi-structured interviews were conducted to determine the opinions of participants on returning to physiotherapy. Maternity and child-care were the main reason returners and potential returners took a break from physiotherapy. The main reason for returning to physiotherapy was because the returner wanted to rather than external factors such as financial hardship. Overall, the experience of returning to physiotherapy has been rewarding for returners and clinical supervisors. Returners and potential returners were highly motivated, keen to learn, and are willing to undertake a period of training to help them return to practice. However, there is only one programme available for returners to re-register as a physiotherapist and no refresher programmes are available. Returners, potential returners, and clinical supervisors thought that a structured re-registration or re-entry programme would need to be flexible to allow for returners’ current needs, commitments, and career directions. What is known about the topic?In nursing, reasons for returning to the profession are change in family circumstance, financial necessity or wishing to use their skills again. Little is known of the circumstances for other health professionals. What does this paper add?Return to physiotherapy was driven by personal motivation rather than financial hardship. Returners are highly motivated, keen to learn, and are willing to undertake a period of training to help them return to practice. What are the implications for practitioners?Flexible methods to enable return to practice are needed. Time away from practice needs to be managed to enable seamless returns, facilitating workforce strategies.
Sustainable workforce reform: case study of Victorian nurse practitioner roles
Authors: Considine Julie , Fielding Katy
Published: August 2010

Nurse practitioner (NP) roles have been identified as a key strategy in the development of a sustainable and responsive health workforce. To date, the focus of research related to NP roles has been on implementation and short-term evaluation of aspects of NP care; however, little is known about the sustainability of NP roles. A major challenge for the healthcare sector is to demonstrate long-term outcomes of NP care and shift the research focus from individual NPs to the effectiveness of healthcare teams that incorporate NPs. This paper draws on a framework of the following domains of sustainability in primary care: political, institutional, financial–economic, workforce and client (or patient) and applies these domains to NP planning in the Victorian context. What is known about the topic?Studies have shown several positive outcomes of NP care including cost, quality of care, patient satisfaction and access to care. What does this paper add?Sustainability of NP roles is poorly understood; however, there are theoretical factors that may be useful in planning for sustainable NP roles. What are the implications for practitioners?There are opportunities to examine traditional roles, governance and funding structures in healthcare to optimise a sustainable contribution to healthcare by NPs and integration of sustainable NP models by health services.
Rural health career pathways: research themes in recruitment and retention
Authors: Fisher Karin A. , Fraser John D.
Published: August 2010

Objective.This paper describes stages in the research literature related to recruitment and retention of health professionals to rural health careers. Data sources.Electronic databases accessed included Medline, CINAHL, Social Sciences and Humanities. Key search terms included ‘high school’, ‘career choices’, ‘rural’, ‘attachment’, ‘recruitment’ and ‘retention’. Data synthesis.We identified four stages: (1) making career choices; (2) being attached to place; (3) taking up rural practice; and (4) remaining in rural practice. This is termed the ‘rural pipeline’. However, as some stages of the ‘rural pipeline’ refer specifically to the medical profession, we propose an extension of the notion of the medical ‘rural pipeline’ to include other professions such as nursing, midwifery and allied health. Conclusions.Utilising the ‘rural pipeline’ as a template for medicine, nursing and allied health would strengthen current approaches to the recruitment and retention of professionals in rural areas and provide a consolidated evidence base that would assist in policy development to improve availability and service provision of the rural health workforce. Future research that utilises a multidisciplinary approach could explore how the role and relationship between place and identity shape needs of career choices and would provide important information to advance the practical aspects supporting rural health career pathways. What is known about the topic?A universal shortage of rural health professionals is a significant issue and is becoming critical in rural areas of Australia. Although there have been many studies, internationally and in Australia, there are several gaps in recruitment and retention of rural health professionals that require further attention. What does this paper add?This paper examines workforce studies related to recruitment and retention of health professionals to rural health careers. The pipeline, however, refers mainly to the medical profession. The stages in this paper extend the notion of the medical ‘rural pipeline’ to include other professions such as nursing and allied health. This paper focusses on literature concerning developed countries such as Australia, New Zealand, Europe, the USA and Canada and identifies several proposed areas of future research. What are the implications for practitioners?The literature clearly identifies important issues for the rural health workforce. Having an understanding of the key issues underpinning the recruitment and retention of health professionals in rural areas allows the development and enhancement of appropriate workforce strategies. Utilising the ‘rural pipeline’ as a template for medicine, nursing and allied health would strengthen current approaches to the recruitment and retention of professionals in rural areas and provide a consolidated evidence base.
From leader to leadership: clinician managers and where to next?
Authors: Fulop Liz , Day Gary E.
Published: August 2010

Individual clinician leadership is at the forefront of health reforms in Australia as well as overseas with many programs run by health departments (and hospitals) generally focus on the development of individual leaders. This paper argues, along with others, that leadership in the clinician management context cannot be understood from an individualistic approach alone. Clinician managers, especially in the ranks of doctors, are usually described as ‘hybrid-professional managers’ as well as reluctant leaders for whom most leadership theories do not easily apply. Their experiences of leadership development programs run by health departments both in Australia and internationally are likely to be based on an individual leader-focussed approach that is driving health care reforms. These approaches work from three key assumptions: (1) study and fix the person; (2) give them a position or title; and (3) make them responsible for results. Some would argue that the combination of these three approaches equates to heroic and transformational leadership. Several alternative approaches to leadership development are presented to illustrate how reforms in healthcare, and notably in hospitals, must incorporate alternative approaches, such as those based on collective and relational forms of leadership. This does not mean eschewing individual approaches to leadership but rather, thinking of them differently and making them more relevant to the daily experiences of clinician managers. We conclude by highlighting several significant challenges facing leadership development for clinician managers that arise from these considerations.
What is known about the topic?The professional development of clinical managers is topical in Australia at this time. Several professional development approaches emphasise the individual development of the clinician manager. The main emphasis of current programs is developing behaviours and traits in individual managers to make them better leaders. There is little empirical evidence of programs that are designed to strengthen a more distributed model of leadership in Australia.
What does this paper add?At the very least a distributed leadership approach that emphasises relationship-based models should be considered as an alternative to professional development programs that concentrate on developing stronger skills in the individual clinical manager. Other relational-based approaches need to be explored to add to leadership development programs.
What are the implications for practice?Consideration needs to be given to increasing leadership capacity through professional development models that cultivate a shared or distributed leadership approach amongst its clinical leaders and in which the notion of relationship-based or relational-focussed approaches are incorporated.
The sustainability of Medical Morning Handover Reporting: adherence in a regional hospital
Authors: Hannan Terry J. , Bart Stanley , Sharp Colin , Fassett Mathew J. , Fassett Robert G.
Published: August 2010

Background.The Medical Morning Handover Report is a form of clinical handover and is considered to be an essential mechanism for continuity of care and adverse event minimisation within a hospital environment. It is considered a significant Quality of Care activity recommended in Australian Medical Association clinical handover guidelines. The sustainability of such activities has not been reported. Aim.We aimed to assess the sustainability of Medical Morning Handover Reporting (MMHR) in the Department of Medicine at the Launceston General Hospital since its implementation in 2001. Methods.We conducted a quality improvement survey amongst the medical staff (pre-graduate and post graduate medical faculties) to assess its sustainability since implementation in 2001. Results.There were 30 respondents of whom 19 attended MMHR daily, four attended weekly, and only five attended less than weekly. Attendance rates at MMHR were maintained from 2001 to 2009 based on comparisons with previously conducted surveys. Conclusions.This study shows MMHR is sustainable and has evolved in format to incorporate advances in Health Information Technology. We believe adherence is dependent on providing leadership and structure to MMHR. What is known about the topic?Since the mid 2000s, the MMHR has emerged as a significant quality intervention activity in our Department of Medicine, with particular emphasis on the first 12–24 h of a patient's encounter with the hospital with conditions that are considered to be medical diagnoses. When considered relevant follow up feedback on previous admissions is covered by the meeting. What does this paper add?This paper attempts to add measurable end points for the quality of the MMHR meeting, the importance of measuring sustainability and introduce the concepts relating to the use of health information technologies as significant decision support and peer review tools within the meeting. What are the implications for practitioners?This study has several implications for clinicians in hospitals: (1) the Report is an essential component of ongoing quality of care handover to maintain the continuity of care and to apply the necessary variations in care uncovered during the handover process. (2) Strict adherence to the meeting time frame improves the MMHR efficiency. (3) Consultant staff attendance has a strong positive influence on the care and educational benefits of the meeting. (4) The integrated use of e-technologies appears to have a strong positive effect on decision making and education during MMHR.
Dynamics of heat shock protein 90 C-terminal dimerization is an important part of its conformational cycle
Authors: Ratzke C. , Mickler M. , Hellenkamp B. , Buchner J. , Hugel T.
Published: August 2010

The molecular chaperone heat shock protein 90 (Hsp90) is an important and abundant protein in eukaryotic cells, essential for the activation of a large set of signal transduction and regulatory proteins. During the functional cycle, the Hsp90 dimer performs large conformational rearrangements. The transient N-terminal dimerization of Hsp90 has been extensively investigated, under the assumption that the C-terminal interface is stably dimerized. Using a fluorescence-based single molecule assay and Hsp90 dimers caged in lipid vesicles, we were able to separately observe and kinetically analyze N- and C-terminal dimerizations. Surprisingly, the C-terminal dimer opens and closes with fast kinetics. The occupancy of the unexpected C-terminal open conformation can be modulated by nucleotides bound to the N-terminal domain and by N-terminal deletion mutations, clearly showing a communication between the two terminal domains. Moreover our findings suggest that the C- and N-terminal dimerizations are anticorrelated. This changes our view on the conformational cycle of Hsp90 and shows the interaction of two dimerization domains.
Nephromyces, a beneficial apicomplexan symbiont in marine animals
Authors: Saffo Mary Beth , McCoy Adam M. , Rieken Christopher , Slamovits Claudio H.
Published: August 2010

With malaria parasites (Plasmodiumspp.),Toxoplasma, and many other species of medical and veterinary importance its iconic representatives, the protistan phylum Apicomplexa has long been defined as a group composed entirely of parasites and pathogens. We present here a report of a beneficial apicomplexan: the mutualistic marine endosymbiontNephromyces. For more than a century, the peculiar structural and developmental features ofNephromyces, and its unusual habitat, have thwarted characterization of the phylogenetic affinities of this eukaryotic microbe. Using short-subunit ribosomal DNA (SSU rDNA) sequences as key evidence, with sequence identity confirmed by fluorescence in situ hybridization (FISH), we show thatNephromyces, originally classified as a chytrid fungus, is actually an apicomplexan. Inferences from rDNA data are further supported by the several apicomplexan-like structural features inNephromyces, including especially the strong resemblance ofNephromycesinfective stages to apicomplexan sporozoites. The striking emergence of the mutualisticNephromycesfrom a quintessentially parasitic clade accentuates the promise of this organism, and the three-partner symbiosis of which it is a part, as a model for probing the factors underlying the evolution of mutualism, pathogenicity, and infectious disease.
Altered distributions of Gemini of coiled bodies and mitochondria in motor neurons ofTDP-43transgenic mice
Authors: Shan Xiu , Chiang Po-Min , Price Donald L. , Wong Philip C.
Published: August 2010

TAR DNA-binding protein-43 (TDP-43), a DNA/RNA-binding protein involved in RNA transcription and splicing, has been associated with the pathophysiology of neurodegenerative diseases, including ALS. However, the function of TDP-43 in motor neurons remains undefined. Here we use both gain- and loss-of-function approaches to determine roles of TDP-43 in motor neurons. Mice expressing human TDP-43 in neurons exhibited growth retardation and premature death that are characterized by abnormal intranuclear inclusions composed of TDP-43 and fused in sarcoma/translocated in liposarcoma (FUS/TLS), and massive accumulation of mitochondria in TDP-43-negative cytoplasmic inclusions in motor neurons, lack of mitochondria in motor axon terminals, and immature neuromuscular junctions. Whereas an elevated level of TDP-43 disrupts the normal nuclear distribution of survival motor neuron (SMN)-associated Gemini of coiled bodies (GEMs) in motor neurons, its absence prevents the formation of GEMs in the nuclei of these cells. Moreover, transcriptome-wide deep sequencing analysis revealed that a decrease in abundance of neurofilament transcripts contributed to the reduction of caliber of motor axons inTDP-43mice. In concert, our findings indicate that TDP-43 participates in pathways critical for motor neuron physiology, including those that regulate the normal distributions of SMN-associated GEMs in the nucleus and mitochondria in the cytoplasm.
Translationally controlled tumor protein is a conserved mitotic growth integrator in animals and plants
Authors: Brioudes Florian , Thierry Anne-Marie , Chambrier Pierre , Mollereau Bertrand , Bendahmane Mohammed
Published: August 2010

The growth of an organism and its size determination require the tight regulation of cell proliferation and cell growth. However, the mechanisms and regulatory networks that control and integrate these processes remain poorly understood. Here, we address the biological role of
Arabidopsis
translationally controlled tumor protein (AtTCTP) and test its shared functions in animals and plants. The data support a role of plant
AtTCTP
as a positive regulator of mitotic growth by specifically controlling the duration of the cell cycle. We show that, in contrast to animal
TCTP
, plant
AtTCTP
is not implicated in regulating postmitotic growth. Consistent with this finding, plant
AtTCTP
can fully rescue cell proliferation defects in
Drosophila
loss of function for
dTCTP.
Furthermore,
Drosophila dTCTP
is able to fully rescue cell proliferation defects in
Arabidopsis tctp
knockouts. Our data provide evidence that
TCTP
function in regulating cell division is part of a conserved growth regulatory pathway shared between plants and animals. The study also suggests that, although the cell division machinery is shared in all multicellular organisms to control growth, cell expansion can be uncoupled from cell division in plants but not in animals.
Successful Eradication of a Monoclonal Strain ofKlebsiella pneumoniaeduring aK. pneumoniaeCarbapenemase-ProducingK. pneumoniaeOutbreak in a Surgical Intensive Care Unit in Miami, Florida
Authors: Munoz-Price L. Silvia , De La Cuesta Carolina , Adams Stephen , Wyckoff Mary , Cleary Timothy , McCurdy Sandra P. , Huband Michael D. , Lemmon M. Megan , Lescoe MaryKay , Dibhajj Fadia B. , Hayden Mary K. , Lolans Karen , Quinn John P.
Published: August 2010

We describe the investigation and control of aKlebsiella pneumoniaecarbapenemase-producingK. pneumoniaeoutbreak in a 20-bed surgical intensive care unit during the period from January 1, 2009 through January 1, 2010. Nine patients were either colonized or infected with a monoclonal strain ofK. pneumoniae.The implementation of a bundle of interventions on July 2009 successfully controlled the further horizontal spread of this organism.
Magnetic reversal in ion-irradiated FePt thin films
Authors: Mougin A , Ferré J , Plantevin O , Cruguel H , Fortuna F , Bernas H , Marty A , Beigné C , Samson Y
Published: August 2010

Previous work on ion irradiation control of FePt thin film magnetic anisotropy is extended to ultrathin films (2–10 nm). The effects of 30 keV He ion irradiation on the magnetic properties are explored as a function of ion fluence and film thickness. Depending on their growth conditions, the thinnest films exhibit different magnetic properties. Although this affects their final magnetic behaviour, we show that after irradiation at 300 °C the easy magnetization axis may rotate entirely from in-plane to out-of-plane at very low fluences, e.g. 2 × 1013 He+ cm−2 on 5 nm thick film. This demonstrates the extreme sensitivity of the magnetic anisotropy to ion-induced local L10 ordering. Under these conditions, ultrathin films may exhibit perfectly square hysteresis loops with 100% remanent magnetization and low coercivity.
High-contrast top-emitting organic light-emitting diodes with a Ni/ZnS/CuPc/Ni contrast-enhancing stack and a ZnS anti-reflection layer
Authors: Chen Shufen , Xie Jun , Yang Yang , Chen Chunyan , Huang Wei
Published: August 2010

High-contrast top-emitting organic light-emitting diodes are successfully fabricated using a Ni/ZnS/copper-phthalocyanine (CuPc)/Ni contrast-enhancing stack (CES) and a ZnS anti-reflection (AR) layer. The CES and AR layer that are outside the active region reduce the complexity of the device design although their utilization affects the device electrical performance due to morphological deterioration of the device films. After the thickness optimization of the CES and AR coating, high contrast ratios of 139.4 : 1 and 462.3 : 1 are obtained under on-state luminances of 300 and 1000 cd m−2 and an ambient luminance of 140 lux. The reduced reflectance of ambient illumination is mainly due to the anti-reflection ZnS layer and the strong absorption of ambient illumination by the Ni layers, where the CES structure is beneficial for the absorption of ambient illumination by the interfacial reflection of Ni/ZnS and CuPc/Ni.
Electron swarm parameters in pure C2H2 and in C2H2–Ar mixtures and electron collision cross sections for the C2H2 molecule
Authors: Nakamura Yoshiharu
Published: August 2010

Electron swarm parameters (the drift velocity and the longitudinal diffusion coefficient) were measured in pure C2H2 and also in C2H2–Ar mixtures containing 0.517% and 5.06% acetylene over wide E/N ranges. These swarm parameters were analysed using a Boltzmann equation analysis and a set of electron collision cross sections for the C2H2 molecule was derived so that it was consistent with the present swarm data and published ionization coefficient. The present result suggested the presence of a Ramsauer–Townsend minimum in the elastic momentum transfer cross section at 0.08 eV and prominent threshold and resonance peaks in the ν4/ν5 vibrational excitation cross section. The present cross section set was also confirmed to be consistent with the published experimental total cross section of C2H2.
Expression of the Salmonella Spp. Virulence Factor SifA in Yeast Alters Rho1 Activity on Peroxisomes
Authors: Vinh Dani B. N. , Ko Dennis C. , Rachubinski Richard A. , Aitchison John D. , Miller Samuel I.
Published: August 2010

The Salmonella typhimurium effector protein SifA regulates the assembly and tubulation of the Salmonella phagosome. SifA localizes to the phagosome and interacts with the membrane via its prenylated tail. SifA is a structural homologue of another bacterial effector that acts as a GTP-exchange factor for Rho family GTPases and can bind GDP-RhoA. When coexpressed with a bacterial lipase that is activated by RhoA, SifA can induce tubulation of mammalian endosomes. In an effort to develop a genetic system to study SifA function, we expressed SifA and characterized its activity in yeast. GFP-SifA predominantly localized to yeast peroxisomal membranes. Under peroxisome-inducing conditions, GFP-SifA reduced the number of free peroxisomes and promoted the formation of large peroxisomes with membrane invaginations. GFP-SifA activity depended on the recruitment to peroxisomes of wild-type Rho1p and Pex25p, a receptor for Rho1p. GFP-SifA could also rescue the actin organization defects in pex25Δ and rho1 mutants, suggesting that SifA may recruit and potentiate Rho1p activity. We reexamined the distribution of GFP-SifA in mammalian cells and found the majority colocalizing with LAMP1-positive compartment and not with the peroxisomal marker PMP70. Together, these data suggest that SifA may use a similar mode of action via Rho proteins to alter yeast peroxisomal and mammalian endosomal membranes. Further definition of SifA activity on yeast peroxisomes could provide more insight into its role in regulating host membrane dynamics and small GTPases.