bluuebunny/crossref_metadata_2025 huggingface dataset:
Active sonic hedgehog signaling between androgen independent human prostate cancer cells and normal/benign but not cancer‐associated prostate stromal cells
Authors: Shigemura Katsumi , Huang Wen‐Chin , Li Xiangyan , Zhau Haiyen E. , Zhu Guodong , Gotoh Akinobu , Fujisawa Masato , Xie Jingwu , Marshall Fray F. , Chung Leland W. K.
Published: April 2011

BACKGROUND

Sonic hedgehog (Shh) signaling plays a pivotal role in stromal–epithelial interaction during normal development but its role in tumor–stromal interaction during carcinogenic progression is less well defined. Since hormone refractory prostate cancer with bone metastasis is difficult to treat, it is crucial to investigate how androgen independent (AI) human prostate cancer cells communicate with their associated stroma.

METHODS

Shh and its target transcription factor, Gli1 mRNA, were assessed by RT‐PCR and/or quantitative RT‐PCR in co‐cultured cell recombinants comprised of AI C4–2 either with NPF (prostate fibroblasts from normal/benign prostate gland) or CPF (cancer‐associated stromal fibroblasts) under Shh/cyclopamine (a hedgehog signaling inhibitor) treatment. Human bone marrow stromal (HS27A) cells were used as controls. In vivo investigation was performed by checking serum PSA and immunohistochemical staining for the apoptosis‐associated M30 gene in mice bearing chimeric C4–2/NPF tumors.

RESULTS

We found that (1) Shh has minimal growth‐stimulating effects on prostate cancer cells, but it stimulated the growth of NPF but not CPF; (2) active Shh signaling was found between AI C4–2 cells and NPF but not CPF; and (3) osteonectin (ON) is a Gli1 target gene in NPF and not in CPF, and ON up‐regulation in NPF can be blocked by cyclopamine

CONCLUSIONS

Based on co‐culture and chimeric tumor models, active Shh‐mediated signaling was demonstrated between AI prostate cancer and NPF in a paracrine‐ and tumor progression‐dependent manner. Our study suggests that drugs like cyclopamine that interfere with Shh signaling could be beneficial in preventing AI progression in prostate cancer cells. Prostate 71:1711–1722, 2011. © 2011 Wiley Periodicals, Inc.
Mechanistic role of NS4A and substrate in the activation of HCV NS3 protease
Authors: Zhu Haimei , Briggs James M.
Published: April 2011

Hepatitis C virus (HCV) NS3 protease is the key enzyme for its maturation. Three hypotheses have been advanced in the literature to demonstrate the mechanism of the activation of the HCV NS3 protease. A virus‐encoded protein NS4A and substrate are proposed to be involved in the activation of the HCV NS3 protease. However, the three hypotheses are not completely consistent with one another. Multiple molecular dynamics simulations were performed on various NS3 protease systems: free NS3 protease, NS3/4A, NS3/inhibitor, and NS3/4A/inhibitor complexes, to further unravel the mechanism of the activation of the NS3 protease. Simulation results suggest that the binding of NS4A induces a classic serine protease conformation of the catalytic triad of the NS3 protease. NS4A rearranges the secondary structure of both the N‐terminus and catalytic site of the NS3 protease, reduces the mobility of the global structure of the NS3 protease, especially the catalytic site, and provides a rigid and tight structure, except for the S1 pocket, for the binding and hydrolysis of substrates. The binding of substrate also contributes to the activation of the NS3 protease by an induced‐fit of the classic serine protease catalytic triad. However, the global structure of the NS3 protease is still loose and highly flexible without stable secondary structural elements, such as helix α0 at the N‐terminus and helix α1 and β‐sheet E1‐F1 at the catalytic site. The structure of the NS3 protease without NS4A is not suitable for the binding and hydrolysis of substrates. Proteins 2011; © 2011 Wiley‐Liss, Inc.
A missense mutation in CLIC2 associated with intellectual disability is predicted by in silico modeling to affect protein stability and dynamics
Authors: Witham Shawn , Takano Kyoko , Schwartz Charles , Alexov Emil
Published: April 2011

Large‐scale next generation resequencing of X chromosome genes identified a missense mutation in the CLIC2 gene on Xq28 in a male with X‐linked intellectual disability (XLID) and not found in healthy individuals. At the same time, numerous nsSNPs (nonsynonomous SNP) have been reported in the CLIC2 gene in healthy individuals indicating that the CLIC2 protein can tolerate amino acid substitutions and be fully functional. To test the possibility that p.H101Q is a disease‐causing mutation, we performed in silico simulations to calculate the effects of the p.H101Q mutation on CLIC2 stability, dynamics, and ionization states while comparing the effects obtained for presumably harmless nsSNPs. It was found that p.H101Q, in contrast with other nsSNPs, (a) lessens the flexibility of the joint loop which is important for the normal function of CLIC2, (b) makes the overall 3D structure of CLIC2 more stable and thus reduces the possibility of the large conformational change expected to occur when CLIC2 moves from a soluble to membrane form, and (c) removes the positively charged residue, H101, which may be important for the membrane association of CLIC2. The results of in silico modeling, in conjunction with the polymorphism analysis, suggest that p.H101Q may be a disease‐causing mutation, the first one suggested in the CLIC family. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Structural studies of the Nudix GDP‐mannose hydrolase from E. coli reveals a new motif for mannose recognition
Authors: Boto Agedi N. , Xu Wenlian , Jakoncic Jean , Pannuri Archana , Romeo Tony , Bessman Maurice J. , Gabelli Sandra B. , Amzel L. Mario
Published: April 2011

The Nudix hydrolase superfamily, characterized by the presence of the signature sequence GX5EX7REUXEEXGU (where U is I, L, or V), is a well‐studied family in which relations have been established between primary sequence and substrate specificity for many members. For example, enzymes that hydrolyze the diphosphate linkage of ADP‐ribose are characterized by having a proline 15 amino acids C‐terminal of the Nudix signature sequence. GDPMK is a Nudix enzyme that conserves this characteristic proline but uses GDP‐mannose as the preferred substrate. By investigating the structure of the GDPMK alone, bound to magnesium, and bound to substrate, the structural basis for this divergent substrate specificity and a new rule was identified by which ADP‐ribose pyrophosphatases can be distinguished from purine‐DP‐mannose pyrophosphatases from primary sequence alone. Kinetic and mutagenesis studies showed that GDPMK hydrolysis does not rely on a single glutamate as the catalytic base. Instead, catalysis is dependent on residues that coordinate the magnesium ions and residues that position the substrate properly for catalysis. GDPMK was thought to play a role in biofilm formation because of its upregulation in response to RcsC signaling; however, GDPMK knockout strains show no defect in their capacity of forming biofilms. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Kaurenoic Acid from Pulp of Annona cherimolia in regard to Annonaceae‐induced Parkinsonism
Authors: Guillopé R. , Escobar‐Khondiker M. , Guérineau V. , Laprévote O. , Höglinger G. U. , Champy P.
Published: April 2011

Guadeloupean Parkinsonism has been linked epidemiologically to the consumption of Annonaceae fruits. These were proposed to be etiological agents for sporadic atypical Parkinsonism worldwide, because of their content of neurotoxins such as isoquinolinic alkaloids and Annonaceous acetogenins. The pulp of Annona cherimolia Mill. from Spain was screened for these toxic molecules using Matrix‐Assisted Laser Desorption Ionisation – Time of Flight mass spectrometry (MALDI‐TOF MS) and it was found not to be a source of exposure. However, kaurenoic acid, a diterpene considered to be cytotoxic, was detected in high amounts (66 mg/fresh fruit). Treatment of rat embryonic striatal primary cultures, up to a high concentration (50 µ m), did not cause neuronal death nor astrogliosis, suggesting that this molecule is not at risk of implication in human neurodegenerative diseases. Copyright © 2011 John Wiley & Sons, Ltd.
Potential energy surfaces for van der waals complexes of rare gases with H2S and H2S2: Extension to xenon interactions and hyperspherical harmonics representation
Authors: Barreto Patrícia R. P. , Albernaz Alessandra F. , Palazzetti Federico
Published: April 2011

This article is an account and extension of a series of recent investigations, which using extensive quantum chemical methods provide analytical hyperspherical representations of the potential energy surfaces for the interactions of rare gases with H2S as a rigid molecule, and H2S2, considered as a floppy molecule with respect to torsional mode. For the H2S‐rare gas systems, the representation is based on a minimal model, here introduced and discussed. For H2S2, the study of the interaction with Xe, not considered previously, completes the series. The results are discussed with reference to the properties and trends expected for interactions of van der Waals type. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Development of a robotic FD‐CT‐guided navigation system for needle placement—preliminary accuracy tests
Authors: Tovar‐Arriaga Saúl , Tita Ralf , Pedraza‐Ortega Jesús Carlos , Gorrostieta Efren , Kalender Willi A.
Published: April 2011

Background

A needle placement system using a serial robot arm for manipulation of biopsy and/or treatment needles is introduced. A method for fast calibration of the robot and the preliminary accuracy tests of the robotic system are presented.

Methods

The setup consists of a DLR/KUKA Light Weight Robot III especially designed for safe human/robot interaction mounted on a mobile platform, a robot‐driven angiographic C‐arm system and a navigation system.

Results

Calibration of the robot with the navigation system has a residual error of 0.23 mm (rms) with a standard deviation of ± 0.1 mm. Needle targeting accuracy with different trajectories was 1.2 mm (rms) with a standard deviation of ± 0.4 mm.

Conclusions

Robot absolute positioning accuracy was reduced to the navigation camera accuracy. The approach includes control strategies that may be very useful for interventional applications. Copyright © 2011 John Wiley & Sons, Ltd.
Tuning the Mechanical Properties of Composites from Elastomeric to Rigid Thermoplastic by Controlled Addition of Carbon Nanotubes
Authors: Khan Umar , May Peter , O’Neill Arlene , Vilatela Juan J. , Windle Alan H. , Coleman Jonathan N
Published: April 2011

A commercial thermoplastic polyurethane is identified for which the addition of nanotubes dramatically improves its mechanical properties. Increasing the nanotube content from 0% to 40% results in an increase in modulus, Y, (0.4–2.2 GPa) and stress at 3% strain, σϵ = 3%, (10–50 MPa), no significant change in ultimate tensile strength, σB, (≈50 MPa) and decreases in strain at break, ϵB, (555–3%) and toughness, T, (177–1 MJ m−3). This variation in properties spans the range from compliant and ductile, like an elastomer, at low mass fractions to stiff and brittle, like a rigid thermoplastic, at high nanotube content. For mid‐range nanotube contents (≈15%) the material behaves like a rigid thermoplastic with large ductility: Y = 1.5 GPa, σϵ = 3% = 36 MPa, σB = 55 MPa, ϵB = 100% and T = 50 MJ m−3. Analysis suggests that soft polyurethane segments are immobilized by adsorption onto the nanotubes, resulting in large changes in mechanical properties.
Improving penetration testing through static and dynamic analysis
Authors: Halfond William G. J. , Choudhary Shauvik Roy , Orso Alessandro
Published: April 2011

Penetration testing is widely used to help ensure the security of web applications. Using penetration testing, testers discover vulnerabilities by simulating attacks on a target web application. To do this efficiently, testers rely on automated techniques that gather input vector information about the target web application and analyze the application's responses to determine whether an attack was successful. Techniques for performing these steps are often incomplete, which can leave parts of the web application untested and vulnerabilities undiscovered. This paper proposes a new approach to penetration testing that addresses the limitations of current techniques. The approach incorporates two recently developed analysis techniques to improve input vector identification and detect when attacks have been successful against a web application. This paper compares the proposed approach against two popular penetration testing tools for a suite of web applications with known and unknown vulnerabilities. The evaluation results show that the proposed approach performs a more thorough penetration testing and leads to the discovery of more vulnerabilities than both the tools. Copyright © 2011 John Wiley & Sons, Ltd.
Motor activity affects dopaminergic and noradrenergic systems of the dorsal horn of the rat lumbar spinal cord
Authors: Gerin Christine G. , Smith Kristin , Hill Seritta , Hill Angela , Madueke Ikenna C.
Published: April 2011

Dopamine (DA) and noradrenaline (NA) modulate responses to nociceptive stimuli, within the dorsal horn of the spinal cord. Both neurotransmitters may play a role in supraspinal regulation in response to proprioceptive afferences to the dorsal horn. However, direct evidence of changes in neurotransmitter release within the dorsal horn due to non‐noxious stimuli is lacking. The present study was designed to determine, whether non‐nociceptive exercise produces changes in release of DA and NA within the dorsal horn, and whether these changes are associated with long‐lasting inhibition after the exercise stops. Microdialysis probes, implanted in layers 2–5 of Rexed, in combination with high‐performance liquid chromatography coupled to electrochemical detection (HPLC‐EC) were used to measure concentrations of DA and NA metabolite (MHPG) in lumbar spinal cords of rats. Microdialysate was sampled before, during, and after a treadmill exercise of one hour. Results indicate that DA and NA releases are inhibited during non‐nociceptive motor activity. At rest, DA concentration was 204 ± 10.5 pg/10 μl and was significantly decreased during exercise to −11.4% (P ≤ 0.05). Greater decrease occurred after 30 min of exercise and was of −31.4% (P ≤ 0.05). Similarly, MHPG was significantly decreased of −18% during exercise (P ≤ 0.05). When exercise stopped, both systems showed long‐lasting inhibition. Exercise post‐release lasted 30 min for DA and 90 min for MHPG. MHPG greatest decrease of −47.8% occurred 30 min after stopping the exercise (P ≤ 0.001). Thus, DA and NA systems seem to respond to exercise‐induced proprioceptive afferent stimuli to the dorsal horn. Synapse, 2011. © 2011 Wiley‐Liss, Inc.
Ethanol production by a new pentose‐fermenting yeast strain, Scheffersomyces stipitis UFMG‐IMH 43.2, isolated from the Brazilian forest
Authors: Ferreira Adriana D. , Mussatto Solange I. , Cadete Raquel M. , Rosa Carlos A. , Silva Silvio S.
Published: April 2011

The ability of a recently isolated Scheffersomyces stipitis strain (UFMG‐IMH 43.2) to produce ethanol from xylose was evaluated. For the assays, a hemicellulosic hydrolysate produced by dilute acid hydrolysis of sugarcane bagasse was used as the fermentation medium. Initially, the necessity of adding nutrients (MgSO4·7H2O, yeast extract and/or urea) to this medium was verified, and the yeast extract supplementation favoured ethanol production by the yeast. Then, in a second stage, assays under different initial xylose and cell concentrations, supplemented or not with yeast extract, were performed. All these three variables showed significant (p < 0.05) influence on ethanol production. The best results (ethanol yield and productivity of 0.19 g/g and 0.13 g/l/h, respectively) were obtained using the hydrolysate containing an initial xylose concentration of 30 g/l, supplemented with 5.0 g/l yeast extract and inoculated with an initial cell concentration of 2.0 g/l. S. stipitis UFMG‐IMH 43.2 was demonstrated to be a yeast strain with potential for use in xylose conversion to ethanol. The establishment of the best fermentation conditions was also proved to be of great importance to increasing the product formation by this yeast strain. These findings open up new perspectives for the establishment of a feasible technology for ethanol production from hemicellulosic hydrolysates. Copyright © 2011 John Wiley & Sons, Ltd.
Predictive Factors for Bile Leakage After Hepatectomy: Analysis of 505 Consecutive Patients
Authors: Yoshioka Ryuji , Saiura Akio , Koga Rintaro , Seki Makoto , Kishi Yoji , Yamamoto Junji
Published: April 2011

Background

Bile leakage is the most common complication after hepatectomy and its incidence is not declining. The aim of the present study was to identify predictive factors for bile leakage.

Methods

Clinical data from 505 consecutive patients who underwent hepatectomy without extrahepatic bile duct resection in our department between January 2006 and December 2009 were reviewed retrospectively.

Results

The incidence of bile leakage was found to be 6.7%. Multivariate analysis identified three independent factors that were significantly correlated with the occurrence of bile leakage: (1) repeat hepatectomy (P = 0.002; odds ratio [OR] 3.439; 95% confidence interval [CI] 1.552–7.618), (2) a cut surface area ≥57.5 cm2 (P = 0.004; OR 5.296; 95% CI 1.721–16.302), and (3) intraoperative blood loss ≥775 ml (P = 0.01; OR 2.808; 95% CI 1.280–6.160).

Conclusion

More meticulous management is needed to prevent bile leakage in high‐risk patients.
Twenty Years of Experience in the Treatment of Spontaneous Aorto‐venous Fistulas in a Developing Country
Authors: Davidovic Lazar , Dragas Marko , Cvetkovic Slobodan , Kostic Dusan , Cinara Ilijas , Banzic Igor
Published: April 2011

Background

One of the rare forms of abdominal aortic aneurysm (AAA) rupture is the rupture into great abdominal veins such as the inferior vein cava (IVC), the iliac veins, or the left renal vein, with the formation of direct or indirect aorto‐caval fistula (ACF). The purpose of the present study was to summarize 20 years of experience at a single referral center for vascular surgery in a developing country, and to discuss the clinical presentation, diagnosis, treatment options, and outcome of patients with spontaneous aorto‐venous fistulas (AVF) caused by ruptured aortic aneurysms.

Materials and methods

Retrospective database review identified 50 patients treated in our institution for aorto‐venous fistulas (AVF) caused by spontaneous AAA rupture in the 20 years 1991–2010. Pulsating abdominal mass and low back pain were the leading symptoms on admission in our patients. Signs of shock, congestive heart failure, or pelvic and lower extremity venous hypertension were present in 48%, 26%, and 75% of the patients, respectively. Diagnosis of AVF was based on physical examination, duplex ultrasonography, conventional angiography, or multislice computed tomography (MSCT). In 40% of the patients the presence of AVF has not been recognized before surgery. All patients were treated with open surgery.

Results

After proximal and distal bleeding control the fistula was closed with direct suture (92%) or patch angioplasty (8%). Aortic reconstruction followed with tubular (22%) or bifurcated (78%) synthetic graft. Six (12%) patients died. The causes of death were excessive intraoperative blood loss, myocardial infarction, left colon gangrene and multiple organ failure.

Conclusions

Spontaneous AVFs caused by aneurysmal rupture are not uncommon, and they require prompt surgical or endovascular treatment. Routine use of multislice CT in patients with acute aortic syndrome is probably the best way to the correct diagnosis of aorto‐venous fistulas and planning of the optimal treatment.
Religiosity and Adolescent Substance Use in Central Mexico: Exploring the Influence of Internal and External Religiosity on Cigarette and Alcohol Use
Authors: Marsiglia Flavio Francisco , Ayers Stephanie L. , Hoffman Steven
Published: April 2011

This study explores the multidimensional nature of religiosity on substance use among adolescents living in central Mexico. From a social capital perspective, this article investigates how external church attendance and internal religious importance interact to create differential pathways for adolescents, and how these pathways exert both risk and protective influences on Mexican youth. The data come from 506 self‐identified Roman Catholic youth (ages 14–17) living in a semi‐rural area in the central state of Guanajuato, Mexico, and attending alternative secondary schools. Findings indicate that adolescents who have higher church attendance coupled with higher religious importance have lower odds of using alcohol, while cigarette use is lower among adolescents who have lower church attendance and lower religious importance. Adolescents are most at risk using alcohol and cigarettes when church attendance is higher but religious importance is lower. In conclusion, incongruence between internal religious beliefs and external church attendance places Mexican youth at greater risk of alcohol and cigarette use. This study not only contributes to understandings of the impact of religiosity on substance use in Mexico, but highlights the importance of understanding religiosity as a multidimensional phenomenon which can lead to differential substance use patterns.
Preparation of Deoiled Soy Lecithin by Ultrafiltration
Authors: Liu Fangbo , Liu Yuanfa , Liu Xiaojun , Shan Liang , Wang Xingguo
Published: April 2011

Deoiling of soy lecithin through ultrafiltration (UF) using an inorganic ceramic membrane was examined in a favorable solvent medium (hexane). Phospholipid (PL) reverse micelles with an average particle size of 9.8 nm were prepared in a 1:3 soy lecithin/hexane system (m/m) with 9% water added at a temperature of 25 °C. Consequently, an inorganic ceramic membrane with a pore size of 5 nm was selected. UF was employed in continuous diafiltration mode at transmembrane pressure (TMP) of 0.25 MPa, and a final deoiled lecithin product with a high acetone insoluble (AI) content of 96.32% was obtained at a yield of around 84%.
Überregionale Partnerschaften – was können sie leisten?
Authors: Pennekamp Sandra
Published: April 2011

Supra-regional partnerships between metropolitan and rural areas are seen as an approach to promote growth and innovation. They should also give new stimulation to the development of regional governance. In this paper some expectations concerning supra-regional partnerships are examined regarding the tasks of spatial development policy. The paper is based on results of an analysis of demonstration projects of supra-regional partnerships. It shows some prospects of supra-regional partnerships but also its requirements and constraints.
Simulating the Effects of Acculturation and Return Migration on the Maternal and Infant Health of Mexican Immigrants in the United States: A Research Note
Authors: Ceballos Miguel
Published: April 2011

A significant body of research on minority health shows that although Latino immigrants experience unexpectedly favorable outcomes in maternal and infant health, this advantage deteriorates with increased time of residence in the United States. This study evaluates the underlying assumptions of two competing hypotheses that explain this paradox. The first hypothesis attributes this deterioration to possible negative effects of acculturation and behavioral adjustments made by immigrants while living in the United States, and the second hypothesis attributes this deterioration to the mechanism of selective return migration. Hypothetical probabilistic models are simulated for assessing the relationship between duration and birth outcomes based on the assumptions of these two hypotheses. The results are compared with the empirical research on the maternal and infant health of first-generation, Mexican-origin immigrant women in the United States. The analysis provides evidence that a curvilinear pattern of duration and birth outcomes can be explained by the joint effects of both acculturation and selective return migration in which the former affects health status over the longer durations, and the latter affects health status at shorter durations.
Estimating the Effect of Smoking on Slowdowns in Mortality Declines in Developed Countries
Authors: Rostron Brian L. , Wilmoth John R.
Published: April 2011

Declines in mortality rates for females at older ages in some developed countries, including the United States, have slowed in recent decades even as decreases have steadily continued in some other countries. This study presents a modified version of the indirect Peto-Lopez method, which uses lung cancer mortality rates as a proxy for smoking exposure, to analyze this trend. The modified method estimates smoking-attributable mortality for more-specific age groups than does the Peto-Lopez method. An adjustment factor is also introduced to account for low mortality in the indirect method’s study population. These modifications are shown to be useful specifically in the estimation of deaths attributable to smoking for females at older ages, and in the estimation of smoking-attributable mortality more generally. In a comparison made between the United States and France with the modified method, smoking is found to be responsible for approximately one-half the difference in life expectancy for females at age 65.
Hydrologic controls on equilibrium soil depths
Authors: Nicótina L. , Tarboton D. G. , Tesfa T. K. , Rinaldo A.
Published: April 2011

This paper deals with modeling the mutual feedbacks between runoff production and geomorphological processes and attributes that lead to patterns of equilibrium soil depth. Our primary goal is an attempt to describe spatial patterns of soil depth resulting from long‐term interactions between hydrologic forcings and soil production, erosion, and sediment transport processes under the framework of landscape dynamic equilibrium. Another goal is to set the premises for exploiting the role of soil depths in shaping the hydrologic response of a catchment. The relevance of the study stems from the massive improvement in hydrologic predictions for ungauged basins that would be achieved by using directly soil depths derived from geomorphic features remotely measured and objectively manipulated. Hydrological processes are here described by explicitly accounting for local soil depths and detailed catchment topography. Geomorphological processes are described by means of well‐studied geomorphic transport laws. The modeling approach is applied to the semiarid Dry Creek Experimental Watershed, located near Boise, Idaho. Modeled soil depths are compared with field data obtained from an extensive survey of the catchment. Our results show the ability of the model to describe properly the mean soil depth and the broad features of the distribution of measured data. However, local comparisons show significant scatter whose origins are discussed.
An experimental streamflow reconstruction for the River Murray, Australia, 1783–1988
Authors: Gallant Ailie J. E. , Gergis Joëlle
Published: April 2011

We present an experimental reconstruction of River Murray streamflow to assess present‐day variations in the context of the past two centuries. Nine annually resolved paleoclimate proxy records from the Australasian region are used to develop a reconstruction of streamflow from 1783 to 1988. An ensemble of reconstructions is presented, providing probabilistic estimates of River Murray flows for each year back in time. The best‐estimate reconstruction captures approximately 23% (50%) of annual (decadal) naturalized streamflow variability. High and low streamflow phases and their association with decadal climate variability in the Pacific are discussed. Reconstructed River Murray streamflow shows considerable variation since 1783. We estimate that there is a 2.3% chance that the 1998–2008 record low decadal streamflow deficit has been exceeded since European settlement. Stochastic simulations of the decadal variations in River Murray streamflow are computed using the paleostreamflow reconstruction to estimate model parameters. From these simulations, we estimate that the 1998–2008 streamflow deficit has an approximate 1 in 1500 year return period. As climate models are assessed relative to short instrumental records, future projections of decadal‐scale variations in Murray‐Darling Basin (MDB) streamflow may be inadequately represented. Given the immense socioeconomic importance of Australia's “food bowl,” future paleoclimate and modeling efforts should be directed at understanding variability at this scale. This would greatly enhance our capacity to estimate regional sensitivity of the MDB's hydroclimate to further anthropogenic influences.
The influence of different excipients and storage procedures on hCG (human Corionic Gonadotropin) as evidenced by spectrophotometry
Authors: Belluscio Daniel Oscar , Vaney Sergio Ariel
Published: April 2011

Our studies concluded that changes in either PH, temperature, electrolytes, excipients, alcohol or silver modify the chemical structure of hCG as evidenced by UV-Spectrophotometry.
Unrepaired clustered DNA lesions induce chromosome breakage in human cells
Authors: Asaithamby Aroumougame , Hu Burong , Chen David J.
Published: April 2011

Clustered DNA damage induced by ionizing radiation is refractory to repair and may trigger carcinogenic events for reasons that are not well understood. Here, we used an in situ method to directly monitor induction and repair of clustered DNA lesions in individual cells. We showed, consistent with biophysical modeling, that the kinetics of loss of clustered DNA lesions was substantially compromised in human fibroblasts. The unique spatial distribution of different types of DNA lesions within the clustered damages, but not the physical location of these damages within the subnuclear domains, determined the cellular ability to repair the damage. We then examined checkpoint arrest mechanisms and yield of gross chromosomal aberrations. Induction of nonrepairable clustered damage affected only G2 accumulation but not the early G2/M checkpoint. Further, cells that were released from the G2/M checkpoint with unrepaired clustered damage manifested a spectrum of chromosome aberrations in mitosis. Difficulties associated with clustered DNA damage repair and checkpoint release before the completion of clustered DNA damage repair appear to promote genome instability that may lead to carcinogenesis.
Optimized fabrication of high-quality La0.67Sr0.33MnO3 thin films considering all essential characteristics
Authors: Boschker H , Huijben M , Vailionis A , Verbeeck J , van Aert S , Luysberg M , Bals S , van Tendeloo G , Houwman E P , Koster G , Blank D H A , Rijnders G
Published: April 2011

In this paper, an overview of the fabrication and properties of high-quality La0.67Sr0.33MnO3 (LSMO) thin films is given. A high-quality LSMO film combines a smooth surface morphology with a large magnetization and a small residual resistivity, while avoiding precipitates and surface segregation. In the literature, typically only a few of these issues are adressed. We therefore present a thorough characterization of our films, which were grown by pulsed laser deposition. The films were characterized with reflection high energy electron diffraction, atomic force microscopy, x-ray diffraction, magnetization and transport measurements, x-ray photoelectron spectroscopy and scanning transmission electron microscopy. The films have a saturation magnetization of 4.0 µB/Mn, a Curie temperature of 350 K and a residual resistivity of 60 µΩ cm. These results indicate that high-quality films, combining both large magnetization and small residual resistivity, were realized. A comparison between different samples presented in the literature shows that focussing on a single property is insufficient for the optimization of the deposition process. For high-quality films, all properties have to be adressed. For LSMO devices, the thin-film quality is crucial for the device performance. Therefore, this research is important for the application of LSMO in devices.
Fabrication and electrical characterization of polyaniline/silicon carbide heterojunctions
Authors: Felix J F , de Vasconcelos E A , da Silva E F , de Azevedo W M
Published: April 2011

We report on the fabrication of silicon carbide/polyaniline heterojunctions produced by spin coating of polyaniline films onto n-type 6H-SiC and 4H-SiC substrates. Atomic force microscopy was used to estimate the surface roughness, and their electrical characteristics were investigated by means of current, capacitance and conductance measurements as a function of frequency and voltages. Reproducible characteristics and rectification ratios as high as 2 × 106 at ±2 V for the 6H-SiC based heterojunctions were obtained. The devices were modelled as Schottky diodes with series resistance and an oxide interfacial oxide layer to account for interface traps. By analysing the forward bias I–V characteristics, we found that the interface trap density for 4H-SiC/PANI heterojunctions is approximately one order of magnitude higher than for 6H-SiC/PANI heterojunctions, which is consistent with previous studies on SiC/SiO2 interface traps. The average value of interface trap densities for 6H-SiC devices was 8.4 × 1011 eV−1 cm−2 and for 4H-SiC it was 2.7 × 1013 eV−1 cm−2. These values are in the range of previous reports on Schottky diodes with polymer layers.
Influence of gate dielectric on the ambipolar characteristics of solution-processed organic field-effect transistors
Authors: Ribierre J C , Ghosh S , Takaishi K , Muto T , Aoyama T
Published: April 2011

Solution-processed ambipolar organic field-effect transistors based on dicyanomethylene-substituted quinoidal quaterthiophene derivative [QQT(CN)4] are fabricated using various gate dielectric materials including cross-linked polyimide and poly-4-vinylphenol. Devices with spin-coated polymeric gate dielectric layers show a reduced hysteresis in their transfer characteristics. Among the insulating polymers examined in this study, a new fluorinated polymer with a low dielectric constant of 2.8 significantly improves both hole and electron field-effect mobilities of QQT(CN)4 thin films to values as high as 0.04 and 0.002 cm2 V−1 s−1. These values are close to the best mobilities obtained in QQT(CN)4 devices fabricated on SiO2 treated with octadecyltrichlorosilane. The influence of the metal used for source/drain metal electrodes on the device performance is also investigated. Whereas best device performances are achieved with gold electrodes, more balanced electron and hole field-effect mobilities could be obtained using chromium.
Wide-band all-angle acoustic self-collimation by rectangular sonic crystals with elliptical bases
Authors: Cicek Ahmet , Kaya Olgun Adem , Ulug Bulent
Published: April 2011

Self-collimation of acoustic waves in the whole angular range of ±90° in the second and third bands of a two-dimensional rectangular sonic crystal with elliptical basis is demonstrated by examining the band structure and equifrequency contours. 70% and 77% of the second and third bands are available for wide-band all-angle self-collimation spanning a bandwidth of approximately 29% and 25% of the central frequencies of the all-angle self-collimation frequency ranges, respectively. Self-collimation of waves over large distances with a small divergence of beam width in the transverse direction is demonstrated through computations based on the finite element method. The second and third bands available for self-collimation are seen to vary linearly in the vast mid-range where a small group velocity dispersion prevents temporal divergence of waves with different frequencies.
Proposal for an ultrasensitive spintronic strain and stress sensor
Authors: Atulasimha J , Bandyopadhyay S
Published: April 2011

We propose a spintronic strain/stress sensor capable of sensing strain with a sensitivity of ∼10−13 Hz−1/2 at room temperature with an active sensing area of ∼1 cm2 and power dissipation of ∼1 W. This device measures stress or strain by monitoring the change in the spin-polarized current in a parallel array of free-standing nanowire spin valves when the array is subjected to compressive or tensile stress along the wires' length. Such a sensor can be fabricated using a variety of techniques involving nanolithography, self-assembly and epitaxial growth.
Understanding and improving electroluminescence in mill-ground ZnS : Cu,Cl phosphors
Authors: Medling S , France C , Balaban B , Kozina M , Jiang Y , Bridges F , Carter S A
Published: April 2011

We demonstrate that lightly milled ZnS : Cu,Cl phosphors produce AC electroluminescence (EL) emission in devices half as thick and produce up to 5 times the light output as the thinnest devices made with unground phosphors. We also establish minimum and maximum bounds on micro-milling conditions for producing powders that are still viable for AC EL. To understand the cause of the minimum size, we report extended x-ray absorption fine structure (EXAFS) measurements on phosphors sorted by particle size. The EXAFS data show that grinding preferentially damages the initially embedded CuS nano-precipitate. This suggests that grinding cleaves the ZnS : Cu through the embedded CuS nano-precipitates, leaving the CuS nano-precipitates on the surface to be further broken apart by continued grinding, eventually reducing the effectiveness of the CuS-induced electric field enhancement.
A model for the enhancement of gas sensing properties in SnO2–ZnO core–shell nanofibres
Authors: Park Jae Young , Choi Sun-Woo , Kim Sang Sub
Published: April 2011

Sensing properties of the sensors fabricated with SnO2–ZnO core–shell nanofibres were investigated in terms of CO in a comparative manner with the sensors with normal ZnO and SnO2 nanofibres. The results clearly demonstrated that the sensing properties were sharply enhanced by forming a ZnO shell layer on the SnO2 fibres. The mechanism for the enhancement seems to be related to the formation of a fully depleted shell layer due to the presence of heterojunction between the ZnO shell and the SnO2 core fibre. This fully depleted shell layer is likely to pronounce the change in resistance during adsorption and desorption of gaseous species.
ICRF mode conversion flow drive on Alcator C-Mod*
Authors: Lin Y. , Rice J.E. , Wukitch S.J. , Reinke M.L. , Greenwald M.J. , Hubbard A.E. , Marmar E.S. , Podpaly Y. , Porkolab M. , Tsujii N.
Published: April 2011

We have carried out a detailed study of ion cyclotron range of frequency (ICRF) mode conversion (MC) flow drive on the Alcator C-Mod tokamak including its dependence on plasma and RF parameters. The flow drive efficiency is found to strongly depend on the 3He concentration in D(3He) plasmas, a key parameter separating the ICRF minority heating regime and MC regime. At +90° antenna phasing (waves in co-I
p direction) and dipole phasing (waves symmetrical in both directions), we find that ΔV
0, the change in the core toroidal rotation velocity, is in the co-I
p direction, increases with RF power and with I
p (opposite to the 1/I
p intrinsic rotation scaling). The flow drive efficiency decreases at higher plasma density and also at higher antenna frequency. The observed flow drive efficiency in H-mode has been small due to the unfavourable density scaling. The flow drive effect at −90° phasing appears to be saturated or decrease at high RF power. The up–down asymmetry in the MC to the ion cyclotron wave may be the key to understand the flow drive mechanism.
A CHANDRA ACIS STUDY OF THE YOUNG STAR CLUSTER
TRUMPLER 15 IN CARINA AND CORRELATION WITH NEAR-INFRARED SOURCES
Authors: Wang Junfeng , Feigelson Eric D. , Townsley Leisa K. , Broos Patrick S. , Getman Konstantin V. , Wolk Scott J. , Preibisch Thomas , Stassun Keivan G. , Moffat Anthony F. J. , Garmire Gordon , King Robert R. , McCaughrean Mark J. , Zinnecker Hans
Published: April 2011

Using the highest-resolution X-ray observation of the Trumpler 15 star cluster
taken by the Chandra X-ray Observatory, we estimate the total
size of its stellar population by comparing the X-ray luminosity function (XLF)
of the detected sources to a calibrator cluster and identify for the first time
a significant fraction (∼14%) of its individual members. The highest-resolution
near-IR observation of Trumpler 15 (taken by the HAWK-I instrument on the Very
Large Telescope) was found to detect most of our X-ray selected sample of
cluster members, with a K-excess disk frequency of 3.8% ± 0.7%.
The near-IR data, XLF, and published spectral types of the brightest members
support a cluster age estimate (5–10 Myr) that is older than those for the
nearby Trumpler 14 and Trumpler 16 clusters, and suggest that high-mass members
may have already exploded as supernovae. The morphology of the inner ∼0.7 pc
core of the cluster is found to be spherical. However, the outer regions (beyond
∼2 pc) are elongated, forming an “envelope” of stars that, in projection,
appears to connect Trumpler 15 to Trumpler 14; this morphology supports the view
that these clusters are physically associated. Clear evidence of mass
segregation is seen. This study appears in this special issue devoted to the
Chandra Carina Complex Project, a 1.42 deg2
Chandra X-ray survey of the Great Nebula in Carina.
Hyperbolizing metric spaces
Authors: Ibragimov Zair
Published: April 2011

It was proved by M. Bonk, J. Heinonen and P. Koskela that the quasihyperbolic metric hyperbolizes (in the sense of Gromov) uniform metric spaces. In this paper we introduce a new metric that hyperbolizes all locally compact noncomplete metric spaces. The metric is generic in the sense that (1) it can be defined on any metric space; (2) it preserves the quasiconformal geometry of the space; (3) it generalizes the

j
j

-metric, the hyperbolic cone metric and the hyperbolic metric of hyperspaces; and (4) it is quasi-isometric to the quasihyperbolic metric of uniform metric spaces. In particular, the Gromov hyperbolicity of these metrics also follows from that of our metric.
The Schwarzian operator: sequences, fixed points and 𝑁-cycles
Authors: Zemyan Stephen
Published: April 2011

Given a function

f
(
z
)

f(z)

that is analytic in a domain

D
D

, we define the classical Schwarzian derivative

{
f
,
z
}

\{f,z\}

of

f
(
z
)

f(z)

, and mention some of its most useful analytic properties. We explain how the process of iterating the Schwarzian operator produces a sequence of Schwarzian derivatives, and we illustrate this process with examples. Under a suitable restriction, these sequences become

N
N

-cycles of Schwarzian derivatives. Some properties of functions belonging to an

N
N

-cycle are listed. We conclude the article with a collection of related open problems.
Maximum smoothed likelihood for multivariate mixtures
Authors: Levine M. , Hunter D. R. , Chauveau D.
Published: April 2011

We introduce an algorithm for estimating the parameters in a finite mixture of completely unspecified multivariate components in at least three dimensions under the assumption of conditionally independent coordinate dimensions. We prove that this algorithm, based on a majorization-minimization idea, possesses a desirable descent property just as any em algorithm does. We discuss the similarities between our algorithm and a related one, the so-called nonlinearly smoothed em algorithm for the non-mixture setting. We also demonstrate via simulation studies that the new algorithm gives very similar results to another algorithm that has been shown empirically to be effective but that does not satisfy any descent property. We provide code for implementing the new algorithm in a publicly available R package.
General assessment and preliminary assessment following injuries
Authors: Sylla Patricia
Published: April 2011

History taking and physical examination 2

The significance of the past medical, social, and drug history in assessing emergencies and admissions 8

Assessment of patients undergoing surgery 12

Assessing the elderly 18

Physical examination 20

Differential diagnosis of 'the swollen face' by region 24

Preliminary assessment of multiple-injured patients—general points ...
Infections
Authors: Sylla Patricia
Published: April 2011

• Sinusitis 62

• The swollen face—general considerations 64

• The acutely swollen face—fascial tissue spaces 66

• Clinical features of fascial space infections and indicators of severity 68

• Basic principles in the management of fascial space infections 69

• The acutely swollen neck ...
The head
Authors: Sylla Patricia
Published: April 2011

The head—basic anatomy and physiology 94

The head—neurological examination 98

Head injuries—pathophysiology 102

Head injuries—general points 104

Head injuries—assessment 106

Skull fractures 108

Intra-cranial haematomas 110

Head injuries—definitive care 114

Anatomists describe the SCALP as having five layers: Skin, Subcutaneous tissue, Aponeurosis, Loose areolar tissue and Pericranium. Functionally, it can be considered as two layers:...
The neck
Authors: Sylla Patricia
Published: April 2011

Penetrating injuries of the neck 134

The larynx—injuries 136

The larynx—loss of voice 138

Deep neck infections—general points and clinical anatomy 138

The acutely swollen neck 140

The cervical spine in the trauma patient 144

Lumps in the neck 160

Difficulty in swallowing (dysphagia) and aspiration ...
The salivary glands
Authors: Sylla Patricia
Published: April 2011

Salivary gland diseases—general considerations 406

Tumours 406

Calculi (stones) and strictures 407

Infections 408

Salivary gland diseases—miscellaneous considerations 410

Saliva is produced by:

• major salivary glands—parotid, submandibular, and sublingual;

• minor salivary glands—these line the mouth, palate, and lips, and they can occasionally be found in the nose....
Infectious diseases
Authors: Ramrakha Punit S. , Moore Kevin P. , Sam Amir
Published: April 2011

Fever in a traveller 1 446

Fever in a traveller 2 448

Malaria: assessment 450

Malaria: investigations 452

Malaria: management 453

Malaria: anti-malarial therapy 454

Infections presenting with fever and rash 456

Primary varicella infection (chickenpox) 458

Herpes zoster (shingles) 460

aVricella infection control 461...
Rheumatological emergencies
Authors: Ramrakha Punit S. , Moore Kevin P. , Sam Amir
Published: April 2011

Acute monoarthritis: presentation 622

Acute monoarthritis: investigations 624

Septic arthritis 625

Crystal arthropathy 626

Polyarthritis 628

Rheumatoid arthritis 630

Seronegative arthritides (spondyloarthropathies) 631

Reactive arthritis 632

Ankylosing spondylitis 632

Enteropathic arthritis 633

Infections 633

Vasculitis 634

Systemic lupus erythematosus (SLE) 636

Wegener’s granulomatosis and microscopic polyarteritis nodosa (PAN) 1 ...
Dermatological emergencies
Authors: Ramrakha Punit S. , Moore Kevin P. , Sam Amir
Published: April 2011

Cutaneous drug reactions 654

Erythroderma 656

Urticaria 658

Autoimmune bullous disease 660

Eczema herpeticum 662

Herpes zoster 662

Generalized pustular psoriasis 664

Toxic epidermal necrolysis (TEN) 1 666

TEN 2 668

• Maculopapular erythema ± pruritus and scaling. Resolves over 2 weeks when drug is stopped. 46% of cutaneous drug reactions....
Psychiatric emergencies
Authors: Ramrakha Punit S. , Moore Kevin P. , Sam Amir
Published: April 2011

Acute confusion: assessment 670

Acute confusion: management 672

Acute alcohol withdrawal 674

Dealing with violent patients 676

Deliberate self-harm 678

The Mental Health Act and common law 680

Treating patients against their will 682

The law on consent and capacity 683

Patients who do not wish to stay in hospital ...
Drug overdoses
Authors: Ramrakha Punit S. , Moore Kevin P. , Sam Amir
Published: April 2011

Overdoses: general approach 692

Drug overdoses and antidotes 694

Amphetamines 696

Antipsychotic drugs 697

Benzodiazepines 698

β‎-blockers 699

Calcium channel blockers 700

Carbon monoxide 702

Cocaine 704

Cyanide 706

Digoxin 708

Ecstasy 710

Ethanol: acute intoxication 711

Ethylene glycol 712

Flunitrazepam 714

Gamma hydroxybutyric acid (GHB) or liquid ecstasy ...