bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical responsiveness of the endothelial cell of Schlemm's canal: scope, variability and its potential role in controlling aqueous humour outflow
Authors: Zhou E. H. , Krishnan R. , Stamer W. D. , Perkumas K. M. , Rajendran K. , Nabhan J. F. , Lu Q. , Fredberg J. J. , Johnson M.
Published: December 2011

Primary open-angle glaucoma is associated with elevated intraocular pressure, which in turn is believed to result from impaired outflow of aqueous humour. Aqueous humour outflow passes mainly through the trabecular meshwork (TM) and then through pores formed in the endothelium of Schlemm's canal (SC), which experiences a basal-to-apical pressure gradient. This gradient dramatically deforms the SC endothelial cell and potentially contributes to the formation of those pores. However, mechanical properties of the SC cell are poorly defined. Using optical magnetic twisting cytometry and traction force microscopy, here we characterize the mechanical properties of primary cultures of the human SC cell, and for the first time, the scope of their changes in response to pharmacological agents that are known to modulate outflow resistance. Lysophosphatidic acid, sphingosine-1-phosphate (S1P) and thrombin caused an increase in cell stiffness by up to 200 per cent, whereas in most cell strains, exposure to latrunculin A, isoproterenol, dibutryl cyclic-AMP or Y-27632 caused a decrease in cell stiffness by up to 80 per cent, highlighting that SC cells possess a remarkably wide contractile scope. Drug responses were variable across donors. S1P, for example, caused 200 per cent stiffening in one donor strain but only 20 per cent stiffening in another. Isoproterenol caused dose-dependent softening in three donor strains but little or no response in two others, a finding mirrored by changes in traction forces and consistent with the level of expression of β
2
-adrenergic receptors. Despite donor variability, those drugs that typically increase outflow resistance systematically caused cell stiffness to increase, while in most cases, those drugs that typically decrease outflow resistance caused cell stiffness to decrease. These findings establish the endothelial cell of SC as a reactive but variable mechanical component of the aqueous humour outflow pathway. Although the mechanism and locus of increased outflow resistance remain unclear, these data suggest the SC endothelial cell to be a modulator of outflow resistance.
An Euler-type method for the strong approximation of the Cox–Ingersoll–Ross process
Authors: Dereich Steffen , Neuenkirch Andreas , Szpruch Lukasz
Published: December 2011

We analyse the strong approximation of the Cox–Ingersoll–Ross (CIR) process in the regime where the process does not hit zero by a positivity preserving drift-implicit Euler-type method. As an error criterion, we use the
p
th mean of the maximum distance between the CIR process and its approximation on a finite time interval. We show that under mild assumptions on the parameters of the CIR process, the proposed method attains, up to a logarithmic term, the convergence of order 1/2. This agrees with the standard rate of the strong convergence for global approximations of stochastic differential equations with Lipschitz coefficients, despite the fact that the CIR process has a non-Lipschitz diffusion coefficient.
Relaxation to quantum equilibrium for Dirac fermions in the de Broglie–Bohm pilot-wave theory
Authors: Colin Samuel
Published: December 2011

Numerical simulations indicate that the Born rule does not need to be postulated in the de Broglie–Bohm pilot-wave theory, but tends to arise dynamically (relaxation to quantum equilibrium). These simulations were done for a particle in a two-dimensional box whose wave function obeys the non-relativistic Schrödinger equation and is therefore scalar. The chaotic nature of the de Broglie–Bohm trajectories, thanks to the nodes of the wave function which yield to vortices, is crucial for a fast relaxation to quantum equilibrium. For spinors, we typically do not expect any node. However, in the case of the Dirac equation, the de Broglie–Bohm velocity field has vorticity even in the absence of nodes. This observation raises the question of the origin of relaxation to quantum equilibrium for fermions. In this article, we provide numerical evidence to show that Dirac particles also undergo relaxation, by simulating the evolution of various non-equilibrium distributions for two-dimensional systems (the two-dimensional Dirac oscillator and the Dirac particle in a two-dimensional spherical step potential).
Is boldness a resource-holding potential trait? Fighting prowess and changes in startle response in the sea anemone,
Actinia equina
Authors: Rudin Fabian S. , Briffa Mark
Published: December 2011

Contest theory predicts the evolution of a stable mixture of different strategies for fighting. Here, we investigate the possibility that stable between-individual differences in startle-response durations influence fighting ability or ‘resource-holding potential’ (RHP) in the beadlet sea anemone,
Actinia equina
. Both winners and losers showed significant repeatability of pre-fight startle-response durations but mean pre-fight startle-response durations were greater for eventual losers than for eventual winners, indicating that RHP varies with boldness. In particular, individuals with short startle responses inflicted more attacks on their opponent. Both repeatability and mean-level responses were changed by the experience of fighting, and these changes varied with outcome. In losers, repeatability was disrupted to a greater extent and the mean startle-response durations were subject to a greater increase than in winners. Thus, following a fight, this behavioural correlate of RHP behaves in a way similar to post-fight changes in physiological status, which can also vary between winners and losers. Understanding the links between aggression and boldness therefore has the potential to enhance our understanding of both the evolution of animal personality and the ‘winner and loser effects’ of post-fight changes in RHP.
GIGAS CELL1, a Novel Negative Regulator of the Anaphase-Promoting Complex/Cyclosome, Is Required for Proper Mitotic Progression and Cell Fate Determination inArabidopsis
Authors: Iwata Eriko , Ikeda Saki , Matsunaga Sachihiro , Kurata Mariko , Yoshioka Yasushi , Criqui Marie-Claire , Genschik Pascal , Ito Masaki
Published: December 2011

Increased cellular ploidy is widespread during developmental processes of multicellular organisms, especially in plants. Elevated ploidy levels are typically achieved either by endoreplication or endomitosis, which are often regarded as modified cell cycles that lack an M phase either entirely or partially. We identified GIGAS CELL1 (GIG1)/OMISSION OF SECOND DIVISION1 (OSD1) and established that mutation of this gene triggered ectopic endomitosis. On the other hand, it has been reported that a paralog of GIG1/OSD1, UV-INSENSITIVE4 (UVI4), negatively regulates endoreplication onset in Arabidopsis thaliana. We showed that GIG1/OSD1 and UVI4 encode novel plant-specific inhibitors of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. These proteins physically interact with APC/C activators, CDC20/FZY and CDH1/FZR, in yeast two-hybrid assays. Overexpression of CDC20.1 and CCS52B/FZR3 differentially promoted ectopic endomitosis in gig1/osd1 and premature occurrence of endoreplication in uvi4. Our data suggest that GIG1/OSD1 and UVI4 may prevent an unscheduled increase in cellular ploidy by preferentially inhibiting APC/CCDC20 and APC/CFZR, respectively. Generation of cells with a mixed identity in gig1/osd1 further suggested that the APC/C may have an unexpected role for cell fate determination in addition to its role for proper mitotic progression.
Depletion of Langerhans cells in the tongue from patients with advanced‐stage acquired immune deficiency syndrome: relation to opportunistic infections
Authors: Gondak Rogério O , Alves Daniel B , Silva Luiz F F , Mauad Thais , Vargas Pablo A
Published: December 2011

Gondak R O, Alves D B, Silva L F F, Mauad T & Vargas P A  (2012) Histopathology 60, 497–503 Depletion of Langerhans cells in the tongue from patients with advanced‐stage acquired immune deficiency syndrome: relation to opportunistic infections

Aims:  To quantify and compare the expression of Langerhans cells (LCs) in the tongue mucosa of AIDS patients with different opportunistic infections, and from acquired immune deficiency syndrome (AIDS) and non‐AIDS patients with normal tongues, using autopsy material.

Methods and results:  Human leucocyte antigen D‐related (HLA‐DR), CD1a and CD83 antibodies were used to identify and quantify LCs by immunohistochemistry in tongue tissue of 40 AIDS patients (10 with lingual candidiasis, 10 with lingual herpes, 10 with oral hairy leukoplakia and 10 with no lesions) and 23 tongues from human immunodeficiency virus (HIV)‐negative control patients. Quantification was performed by means of conventional morphometry in four different regions (anterior, middle, posterior and lateral) of the tongue. The results were expressed as positive cells per area of epithelium. The AIDS patients presented a lower density of CD1a+ cells (P < 0.001), HLA‐DR (P < 0.003) and CD83 (P < 0.001) in all regions of the tongue compared to the non‐AIDS control group. However, no differences in any of the markers were found when AIDS patients with different opportunistic infections were compared with AIDS patients without tongue infection.

Conclusions:  Advanced stage AIDS patients showed a depletion of LCs in the tongue mucosa. HIV infection induces cytopathic changes in LCs, contributing to their depletion regardless of the presence of oral infections.
Inhibitory effect of rice bran extract on polyphenol oxidase of potato and banana
Authors: Sukhonthara Sukhontha , Theerakulkait Chockchai
Published: December 2011

Rice bran was extracted with water and its effects on potato and banana polyphenol oxidase (PPO) were investigated. Rice bran extract (RBE), conc. 0.3 g mL−1, exhibited PPO inhibition in potato and banana PPO with % inhibition of 69.31% and 47.63%, respectively (P ≤ 0.05). RBE showed a concentration‐dependent inhibition on potato and banana PPO. RBE (conc. 0.3 g mL−1) inhibited potato PPO higher than ascorbic acid, citric acid, NaCl and EDTA (final conc. 20 mg L−1); and it also inhibited banana PPO higher than citric acid, NaCl and EDTA (final conc. 20 mg L−1), respectively. The combination of RBE with citric acid or ascorbic acid appeared to be additive inhibitory effect on banana and potato PPO. Kinetic study of the inhibition on potato and banana PPO by RBE showed that RBE was a mixed‐type inhibitor; however, RBE appeared to be able to act directly on enzyme structure rather than substrate structure.
An orphan sensor kinase controls quinolone signal production via MexT in Pseudomonas aeruginosa
Authors: Zaoui Caroline , Overhage Jörg , Löns Dagmar , Zimmermann Ariane , Müsken Mathias , Bielecki Piotr , Pustelny Christian , Becker Tanja , Nimtz Manfred , Häussler Susanne
Published: December 2011

Pseudomonas aeruginosa employs both N‐acylhomoserine lactone and 2‐alkyl‐4(1H)‐quinolone (AQ)‐mediated interbacterial signalling for the orchestration of a genome‐wide gene regulatory network. Despite the many advances that have been made in understanding the target genes of quorum sensing regulation, little is known on how quorum sensing systems are influenced by environmental cues. In this study, we show that AQ production is modulated by an orphan P. aeruginosa sensor kinase. Transcriptional studies of the sensor kinase (MxtR) mutant demonstrated that an induced expression of MexT, a LysR‐type transcriptional regulator, largely determined the global transcriptional profile. Thereby, overexpression of the MexT‐regulated MexEF‐OprN efflux pump led to a delayed expression of the AQ biosynthetic genes and of AQ‐dependent virulence factors. Furthermore, we demonstrated that autophosphorylation of MxtR was inhibited by ubiquinone, the central electron carrier of respiration in in vitro experiments. Our results elucidate on a mechanism by which P. aeruginosa senses environmental conditions and adapts by controlling the production of interbacterial AQ signal molecules. A regulatory function of a sensor kinase may indicate that there is a pre‐emptive role of adaptation mechanisms that are turned on under distinct environmental conditions and that are important for efficient colonization and pathogenesis.
A novel deletion partly removing the AVP gene causes autosomal recessive inheritance of early‐onset neurohypophyseal diabetes insipidus
Authors: Christensen JH , Kvistgaard H , Knudsen J , Shaikh G , Tolmie J , Cooke S , Pedersen S , Corydon TJ , Gregersen N , Rittig S
Published: December 2011

Christensen JH, Kvistgaard H, Knudsen J, Shaikh G, Tolmie J, Cooke S, Pedersen S, Corydon TJ, Gregersen N, Rittig S. A novel deletion partly removing the AVP gene causes autosomal recessive inheritance of early‐onset neurohypophyseal diabetes insipidus.

Familial neurohypophyseal diabetes insipidus (FNDI) typically presents with age‐dependent penetrance and autosomal dominant inheritance caused by missense variations in one allele of the AVP gene encoding the arginine vasopressin (AVP) prohormone. We present the molecular genetic characteristics underlying an unusual form of FNDI occurring with very early onset and seemingly autosomal recessive inheritance. By DNA amplification and sequencing, we identified a novel variant allele of the AVP gene carrying a 10,396 base pair deletion involving the majority of the AVP gene as well as its regulatory sequences in the intergenic region between the AVP and the OXT gene, encoding the oxytocin prohormone. We found two chromosomes carrying the deletion in affected family members and one in unaffected family members suspected to transmit the deleted allele. Whole‐genome array analysis confirmed the results and excluded the presence of any additional major pathogenic abnormalities. The deletion is predicted to abolish the transcription of the AVP gene, thus the fact that family members heterozygous for the deletion remain healthy argues, in general, against haploinsufficiency as the pathogenic mechanism FNDI. Accordingly, our data is strong support to the prevailing idea that dominant inheritance of FNDI is due to a dominant‐negative effect exerted by variant AVP prohormone.
Who Governs Finance? The Shifting Public–Private Divide in the Regulation of Derivatives, Rating Agencies and Hedge Funds
Authors: Pagliari Stefano
Published: December 2011

The division of responsibilities in the regulation and supervision of financial markets between ‘public’ regulatory agencies and ‘private’ market actors is not fixed; it has radically changed across time. This paper argues that the financial crisis of 2007–2009 has triggered the latest turn in the ‘public–private’ divide in the regulation of finance. Focusing in particular on the extensive reforms that have been introduced in the regulation of over‐the‐counter derivatives, credit rating agencies and hedge funds in Europe and internationally, this paper argues that the response to the financial crisis has brought to a halt the reliance on self‐regulation and market discipline as primary regulatory mechanisms that had characterised the approach of regulators prior to the crisis. However, while public regulatory agencies have consolidated in their hands the authority to regulate and oversee markets previously left outside their regulatory oversight, the content and the purpose of their regulatory intervention continue to present significant element of continuity with the pre‐crisis regulatory model.
Corporate Governance in Crisis? The Politics of EU Corporate Governance Regulation
Authors: Horn Laura
Published: December 2011

This article emphasises the essentially political nature of corporate governance regulation and argues that the transformation of corporate governance regulation is part of a broader political project of economic restructuring and market‐making in the EU. The first part of the analysis focuses on the transformation of company law and corporate governance in the last decade. Here, the article illustrates how company law has become increasingly focused on the rights of shareholders, while worker rights have been relegated to the area of social policies and labour law. The study also traces the shift from a legislative programme centred on company law harmonisation towards a regulatory approach based on minimum requirements and mutual recognition, increasingly geared at adjusting the governance of corporations to the demands of liberalised capital markets. The second section then reflects on the current developments in corporate governance regulation in the context of financial and economic crisis.
The Participation of the European Union in Global Economic Governance Fora
Authors: Hervé Alan
Published: December 2011

Despite its economic importance and successive Treaty reforms, the EU does not always succeed in asserting itself as a leading actor on the international stage. Both internal and external factors influence the EU's participation in international economic governance institutions. They constitute a definite handicap concerning the EU's potential role as a real normative power. At the same time, as indispensable reforms of global economic governance are in the offing, the EU seems to be giving up any claims for better representation within competent organisations and forums, such as the International Monetary Fund.
COMPARISON OF CULTURED TRICHODESMIUM (CYANOPHYCEAE) WITH SPECIES CHARACTERIZED FROM THE FIELD1
Authors: Hynes Annette M. , Webb Eric A. , Doney Scott C. , Waterbury John B.
Published: December 2011

The filamentous, colonial cyanobacterium Trichodesmium has six well‐described species, but many more names. Traditional classification was based on field samples using morphological characteristics such as cell width and length, gas vesicle distribution, and colony morphology. We used the Woods Hole Trichodesmium culture collection to identify 21 cultured strains to species using cell morphology; phycobiliprotein absorption spectra; and sequences of the 16S rRNA gene, the 16S–23S internal transcribed spacer (ITS), and the heterocyst differentiation gene hetR. We compared our results to previous studies of field specimens and found similar clades, though not all phylogenetic groups were represented in culture. Our culture collection represented two of the four major clades of Trichodesmium: clade I, made up of Trichodesmium thiebautii Gomont, Trichodesmium tenue Wille, Katagnymene spiralis Lemmerm., and Trichodesmium hildebrandtii Gomont; and clade III, consisting of Trichodesmium erythraeum Ehrenb. and Trichodesmium contortum Wille. These clades were genetically coherent with similar phycobiliprotein composition, but morphologically diverse. In the continual revision of cyanobacterial taxonomy, genetic and biochemical information is useful and informative complements to morphology for the development of a functional classification scheme.
Text‐Message‐Based Drinking Assessments and Brief Interventions for Young Adults Discharged from the Emergency Department
Authors: Suffoletto Brian , Callaway Clifton , Kristan Jeff , Kraemer Kevin , Clark Duncan B.
Published: December 2011

Background:  Brief interventions have the potential to reduce heavy drinking in young adults who present to the emergency department (ED), but require time and resources rarely available. Text‐messaging (TM) may provide an effective way to collect drinking data from young adults after ED discharge as well as to provide immediate feedback and ongoing support for behavior change. The feasibility of screening young adults in the ED, recruiting them for a TM‐based interventional trial, collecting weekly drinking data through TM, and the variance in drinking outcomes remains unknown.

Methods:  Young adults in 3 urban EDs (n = 45; aged 18 to 24 years, 54% women) identified as hazardous drinkers by the Alcohol Use Disorders Identification Test‐Consumption score were randomly assigned to weekly TM‐based feedback with goal setting (Intervention), weekly TM‐based drinking assessments without feedback (Assessment), or control. Participants in the Intervention group who reported ≥5 (for men) and ≥4 (for women) maximum drinks during any one 24‐hour period were asked whether they would set a goal to reduce their drinking the following week. We describe the interaction with TM and goal setting. We also describe the heavy drinking days (HDDs), drinks per drinking day (DPDD) using timeline follow‐back procedure at baseline and 3 months.

Results:  We screened 109 young adults over 157 hours across 24 unique days and 52 (48%; 95% CI 38 to 50) screened positive for hazardous drinking. Of these, 45 (87%; 95% CI 74 to 94) met inclusion criteria, were enrolled and randomized, and 6 (13%; 95% CI 5 to 27) did not complete 3‐month web‐based follow‐up; 88% (95% CI 84 to 91) of weekly TM‐based drinking assessments were answered, with 77% (95% CI 58 to 90) of participants responding to all 12 weeks. Agreeing to set a goal was associated with a repeat HDD 36% (95% CI 17 to 55) of the time compared with 63% (95% CI 44 to 81) when not willing to set a goal. At 3 months, participants that were exposed to the TM‐based intervention had 3.4 (SD 5.4) fewer HDDs in the last month and 2.1 (SD 1.5) fewer DPDD when compared to baseline.

Conclusions:  TM can be used to assess drinking in young adults and can deliver brief interventions to young adults discharged from the ED. TM‐based interventions have the potential to reduce heavy drinking among young adults but larger studies are needed to establish efficacy.
Synthesis of ZSM‐5 Zeolite Particles Using Triethanol Amine as Structure‐Directing Agent
Authors: Naskar Milan K. , Kundu Debtosh , Chatterjee Minati
Published: December 2011

The ZSM‐5 zeolite particles have been prepared using triethanol amine as structure‐directing agent under static hydrothermal condition at 170°C for 7 days. The particles were characterized by X‐ray diffraction (XRD), thermogravimetry analysis (TGA), differential thermal analysis (DTA), Fourier transform infrared (FTIR) spectroscopy, N2 physisorption measurements, and field emission scanning electron microscopy (FESEM). The crystalline ZSM‐5 was found at 170°C/7 days as shown by XRD. The vibration bands at around 549 and 1226 cm−1 in the FTIR spectra indicated the presence of double 5‐ring in ZSM‐5. The exothermic peak at 395°C in DTA curve indicated the removal of structure‐directing agent. The BET surface area of the particles was 100 m2/g. The FESEM images showed coffin‐shaped and broom‐like crystals of ZSM‐5.
Re‐reading Discourse and Social Psychology: Transforming social psychology
Authors: Potter Jonathan
Published: December 2011

This paper considers one theme in the contemporary legacy of Potter and Wetherell's (1987) Discourse and Social Psychology. It overviews the context that led to that book and considers a series of critical responses from both experimental and critical/qualitative social psychologists. It refutes criticisms and corrects confusions. Focusing on contemporary discursive psychology, it highlights (a) its rigorous use of records of actual behaviour; (b) its systematic focus on normative practices. In methodological terms, it (a) highlights limitations in the use of open‐ended interviews; (b) considers the way naturalistic materials provide access to participants’ own orientations and displays; (c) builds a distinctive logic of sampling and generalization. In theoretical terms, it (a) highlights the way discourse work can identify foundational psychological matters; (b) offers a novel approach to emotion and embodiment; (c) starts to build a matrix of dimensions which are central to the constructing and recognizing of different kinds of social actions. It now offers a fully formed alternative social psychology which coordinates theory and method and a growing body of empirical work.
Learning from Baby Steps
Authors: Wang Wei
Published: December 2011

Basic muscle movement patterns during walking are preserved between newborn and adult humans.
Complement-Mediated Neutralization of Dengue Virus Requires Mannose-Binding Lectin
Authors: Avirutnan Panisadee , Hauhart Richard E. , Marovich Mary A. , Garred Peter , Atkinson John P. , Diamond Michael S.
Published: December 2011

Mannose-binding lectin (MBL) is a key soluble pathogen recognition protein of the innate immune system that binds specific mannose-containing glycans on the surfaces of microbial agents and initiates complement activation via the lectin pathway. Prior studies showed that MBL-dependent activation of the complement cascade neutralized insect cell-derived West Nile virus (WNV) in cell culture and restricted pathogenesis in mice. Here, we investigated the antiviral activity of MBL in infection by dengue virus (DENV), a related flavivirus. Using a panel of naïve sera from mouse strains deficient in different complement components, we showed that inhibition of infection by insect cell- and mammalian cell-derived DENV was primarily dependent on the lectin pathway. Human MBL also bound to DENV and neutralized infection of all four DENV serotypes through complement activation-dependent and -independent pathways. Experiments with human serum from naïve individuals with inherent variation in the levels of MBL in blood showed a direct correlation between the concentration of MBL and neutralization of DENV; samples with high levels of MBL in blood neutralized DENV more efficiently than those with lower levels. Our studies suggest that allelic variation of MBL in humans may impact complement-dependent control of DENV pathogenesis.

IMPORTANCEDengue virus (DENV) is a mosquito-transmitted virus that causes a spectrum of clinical disease in humans ranging from subclinical infection to dengue hemorrhagic fever and dengue shock syndrome. Four serotypes of DENV exist, and severe illness is usually associated with secondary infection by a different serotype. Here, we show that mannose-binding lectin (MBL), a pattern recognition molecule that initiates the lectin pathway of complement activation, neutralized infection of all four DENV serotypes through complement activation-dependent and -independent pathways. Moreover, we observed a direct correlation with the concentration of MBL in human serum and neutralization of DENV infection. Our studies suggest that common genetic polymorphisms that result in disparate levels and function of MBL in humans may impact DENV infection, pathogenesis, and disease severity.
Attitudes to morphine in chronic heart failure patients
Authors: Oxberry Stephen G , Jones Lesley , Clark Andrew L , Johnson Miriam J
Published: December 2011

Objectives

Low-dose opioids are used for the palliation of pain, breathlessness and cough in advanced chronic heart failure (CHF) patients. The authors wanted to determine any potential barriers or facilitators to opioid administration in patients with CHF by assessing their knowledge, concerns and attitudes to morphine therapy.

Methods

Semistructured interviews were held with a purposive sample of 10 men with symptoms of CHF. Data were analysed using a constant comparative approach until thematic saturation.

Results

Four key areas emerged: medication use; symptoms; prior morphine experience; and attitudes, concerns and anxieties regarding morphine use. Despite polypharmacy, participants said that morphine would be acceptable if it was monitored by a trusted healthcare professional. Many patients had experienced morphine before, often in life-threatening situations such as myocardial infarction, when it had helped greatly. Opioids were not strongly associated exclusively with death and dying (in contrast to patient reports in the cancer literature).

Conclusions

Although some concerns about morphine were expressed, these did not appear to override a willingness to consider its use if recommended by a trusted clinician. However, some participants perceived that their doctor was concerned about its use, holding it as a last reserve. Morphine appears to be an acceptable breathlessness treatment option to these people with CHF. Prescribers may need education and reassurance if these medicines are to be used to their full potential and views may be different in other communities.
Society of NeuroInterventional Surgery Standards of Practice: general considerations
Authors: Meyers P M , Blackham K A , Abruzzo T A , Gandhi C D , Higashida R T , Hirsch J A , Moran C J , Narayanan S , Prestigiacomo C J , Tarr R ,   On behalf of the Society for NeuroInterventional Surgery
Published: December 2011

This is the first in a set of documents intended to standardize techniques, procedures, and practices in the field of endovascular surgical neuroradiology. Standards are meant to define core practices for peer review, comparison, and improvement. Standards and guidelines also form the basic dialogue, reporting, and recommendations for ongoing practices and future development.
Cyclohexylamine oxidase as a useful biocatalyst for the kinetic resolution and dereacemization of amines
Authors: Leisch Hannes , Grosse Stephan , Iwaki Hiroaki , Hasegawa Yoshie , Lau Peter C.K.
Published: December 2011

The biocatalytic performance of a cloned cyclohexylamine oxidase derived from Brevibacterium oxydans IH-35A towards structurally different amines was investigated. Cycloalkyl primary amines, alkyl aryl amines, and α-carbon-substituted aliphatic amines were identified as suitable substrates for the biocatalyst based on an activity assay. Kinetic resolutions of several amines by either recombinant whole cells or crude enzyme extracts prepared therefrom gave enantiomerically pure (R)-amines besides the corresponding ketones. When cyclohexylamine oxidase in combination with a borane–ammonia complex as reducing agent was applied to the deracemization of several substrates, excellent enantiomeric ratios (>99:1) and good isolated yields (62%–75%) of the corresponding (R)-amines were obtained.
The role of solvent in organometallic chemistry — Oxidative addition with dichloromethane or chloroform
Authors: Abo-Amer Anwar , McCready Matthew S. , Zhang Fenbao , Puddephatt Richard J.
Published: December 2011

Dimethylplatinum(II) complexes [PtMe2(NN)], with NN = diimine ligand, can react with dichloromethane or chloroform solvent to give the corresponding organoplatinum(IV) complexes [PtClMe2(CH2Cl)(NN)] or [PtClMe2(CHCl2)(NN)], respectively. The products can exist in isomeric forms, corresponding to products of cis or trans oxidative addition. The structures of three dichloromethane adducts and one chloroform adduct are reported.
STUDY ON THE MECHANISM OF VISIBLE ABSORPTION ENHANCEMENT FOR N+ IMPLANTED TiO2 BY RAMAN SPECTROSCOPY
Authors: WANG CHUN-XIAO , CHEN YAN , FAN YU-ZUN , ZHANG YAN-WEN , LIANG QI-YU , WU YUE-DONG , LI DONG-MEI , JIA JIN-FENG , XUE QI-KUN , ZHAO ZI-QIANG , MENG QING-BO , ZHANG SHU-LIN
Published: December 2011

The photoabsorption edge shifting from UV to visible region accompanied with increased intensity and Raman features change was observed for N+ implanted TiO2 . Raman spectra prove the formation of TiN x and oxygen vacancies in the implanted TiO2 , which is considered as the origin of absorption edge shifting. The work may give a hint to increase the photocatalytic activity of TiO2 in the visible region at the molecule level.
Neuromodulation of Vertebrate Locomotor Control Networks
Authors: Miles Gareth B. , Sillar Keith T.
Published: December 2011

Vertebrate locomotion must be adaptable in light of changing environmental, organismal, and developmental demands. Much of the underlying flexibility in the output of central pattern generating (CPG) networks of the spinal cord and brain stem is endowed by neuromodulation. This review provides a synthesis of current knowledge on the way that various neuromodulators modify the properties of and connections between CPG neurons to sculpt CPG network output during locomotion.
Molecular Physiology of pH-Sensitive Background K2P Channels
Authors: Lesage Florian , Barhanin Jacques
Published: December 2011

Background K2P channels are tightly regulated by different stimuli including variations of external and internal pH. pH sensitivity relies on proton-sensing residues that influence channel gating and activity. Gene inactivation in the mouse is a revealing implication of K2P channels in many physiological functions ranging from hormone secretion to central respiratory adaptation. Surprisingly, only a few phenotypic traits of these mice have yet been directly related to the pH sensitivity of K2P channels.
Mina: A Sensorimotor Robotic Orthosis for Mobility Assistance
Authors: Raj Anil K. , Neuhaus Peter D. , Moucheboeuf Adrien M. , Noorden Jerryll H. , Lecoutre David V.
Published: December 2011

While most mobility options for persons with paraplegia or paraparesis employ wheeled solutions, significant adverse health, psychological, and social consequences result from wheelchair confinement. Modern robotic exoskeleton devices for gait assistance and rehabilitation, however, can support legged locomotion systems for those with lower extremity weakness or paralysis. The Florida Institute for Human and Machine Cognition (IHMC) has developed the Mina, a prototype sensorimotor robotic orthosis for mobility assistance that provides mobility capability for paraplegic and paraparetic users. This paper describes the initial concept, design goals, and methods of this wearable overground robotic mobility device, which uses compliant actuation to power the hip and knee joints. Paralyzed users can balance and walk using the device over level terrain with the assistance of forearm crutches employing a quadrupedal gait. We have initiated sensory substitution feedback mechanisms to augment user sensory perception of his or her lower extremities. Using this sensory feedback, we hypothesize that users will ambulate with a more natural, upright gait and will be able to directly control the gait parameters and respond to perturbations. This may allow bipedal (with minimal support) gait in future prototypes.
Bimodal Fluorescence and Magnetic Resonance Imaging Using Water-Soluble Hexagonal NaYF4:Ce,Tb,Gd Nanocrystals
Authors: Ren Wen Ting , Liang Liang Bo , Qi Fei , Sun Zheng Bo , Yang Zhi Yong , Huang Xiao Qi , Wu Qi Zhu , Zhu Hong Yan , Yu Xue Feng , Quan Hong , Gong Qi Yong
Published: December 2011

The present study explored the feasibility of using hexagonal-phase NaYF4:Ce,Tb,Gd nanocrystals as bimodal probes for fluorescence and magnetic resonance (MR) imaging. Using a facile and user-friendly strategy, the NaYF4:Ce,Tb,Gd nanocrystals were synthesized with good water dispensability, high quantum yield (26%), and decent MRT1relaxivity (r1=2.87 mM−1 s−1). The NaYF4:Ce,Tb,Gd NCs conjugated by folic acid presented great efficiency in fluorescence imaging of C6 glioma cellsin vitro. Meanwhile, inin vivoMR experiments on rats, the NaYF4:Ce,Tb,Gd NCs also significantly increasedT1signal in the liver, spleen, and kidney even with a low probe dose. The proposed NaYF4:Ce,Tb,Gd nanoprobes hold promise for simultaneous bimodal fluorescence and MR bioimaging.
Mixed H2/H∞ Performance Analysis and State‐Feedback Control Design for Networked Systems with Fading Communication Channels
Authors: Stoica Adrian-Mihail
Published: December 2011

The purpose of the present paper is to provide a performance analysis approach of networked systems with fading communication channels. For a Ricean model of the fading communication channel, it is shown that the resulting system has a hybrid structure including the continuous‐time dynamics of the networked systems and a discrete‐time dynamics of the communication channels. Moreover, this resulting hybrid system has both multiplicative and additive noise terms. The performance analysis naturally leads to an H2/H∞‐type norm evaluation for systems with finite jumps and multiplicative noise. It is proved that this norm depends on the stabilizing solution of a specific system of coupled Riccati′s equations with jumps. A state‐feedback design problem to accomplish a mixed H2/H∞ performance is also considered. A numerical iterative procedure allowing to compute the stabilizing solution of the Riccati‐type system with jumps is presented. The theoretical results are illustrated by numerical results concerning the tracking performances of a flight formation with fading communication channel. The paper ends with some concluding remarks.
Efficacy and Safety of Standardized Allergen-Removed Rhus verniciflua Stokes Extract in Patients with Advanced or Metastatic Pancreatic Cancer: A Korean Single-Center Experience
Authors: Lee Sanghun , Kim Kyungsuk , Jung Hyunsik , Lee Sookyung , Cheon Seongha , Kim Sehyun , Eo Wankyu , Choi Woncheol
Published: December 2011

Background: Pancreatic cancer has the worst prognosis because of poor response to conventional therapy. We investigated the clinical feasibility of the standardized allergen-removed Rhus verniciflua Stokes (aRVS) extract as a potential therapeutic agent for advanced or metastatic pancreatic cancer. Patients and Methods: From July 2006 to June 2010, patients with advanced or metastatic pancreatic adenocarcinoma were checked in our institution. After applying inclusion/exclusion criteria, 42 patients were eligible for the final analysis. Overall survival, clinical benefit and adverse events of these patients treated with aRVS in the aftercare period were determined. Results: In May 2011, 39 patients had died and the remaining 3 patients were alive with evidence of disease. The mean RVS administration period was 3.86 months (95% confidence interval 2.52–5.20). The median overall survival for the entire population was 7.87 months (95% confidence interval 5.14–10.59), and the 1-year survival rate was 26.2%, which is compatible with external controls. Using univariate and multivariate analyses, aRVS treatment including performance status and prognostic index significantly affected overall survival. A clinical benefit response was also shown by aRVS treatment which was not dependent on concurrent chemotherapy. Adverse reactions to aRVS treatment were mostly mild and self-limiting. Conclusions: The standardized aRVS extract might be beneficial for patients with advanced or metastatic pancreatic cancer since it positively affected overall survival and clinical symptoms without significant adverse effects.
Efficient Calculation of the Gauss-Newton Approximation of the Hessian Matrix in Neural Networks
Authors: Fairbank Michael , Alonso Eduardo
Published: December 2011

The Levenberg-Marquardt (LM) learning algorithm is a popular algorithm for training neural networks; however, for large neural networks, it becomes prohibitively expensive in terms of running time and memory requirements. The most time-critical step of the algorithm is the calculation of the Gauss-Newton matrix, which is formed by multiplying two large Jacobian matrices together. We propose a method that uses backpropagation to reduce the time of this matrix-matrix multiplication. This reduces the overall asymptotic running time of the LM algorithm by a factor of the order of the number of output nodes in the neural network.
Decorrelation of Spiking Variability and Improved Information Transfer Through Feedforward Divisive Normalization
Authors: Tripp Bryan P.
Published: December 2011

Response variability is often positively correlated in pairs of similarly tuned neurons in the visual cortex. Many authors have considered correlated variability to prevent postsynaptic neurons from averaging across large groups of inputs to obtain reliable stimulus estimates. However, a simple average of variability ignores nonlinearities in cortical signal integration. This study shows that feedforward divisive normalization of a neuron's inputs effectively decorrelates their variability. Furthermore, we show that optimal linear estimates of a stimulus parameter that are based on normalized inputs are more accurate than those based on nonnormalized inputs, due partly to reduced correlations, and that these estimates improve with increasing population size up to several thousand neurons. This suggests that neurons may possess a simple mechanism for substantially decorrelating noise in their inputs. Further work is needed to reconcile this conclusion with past evidence that correlated noise impairs visual perception.
A Comparison of Perturbed Initial Conditions and Multiphysics Ensembles in a Severe Weather Episode in Spain
Authors: Tapiador Francisco J. , Tao Wei-Kuo , Shi Jainn Jong , Angelis Carlos F. , Martinez Miguel A. , Marcos Cecilia , Rodriguez Antonio , Hou Arthur
Published: December 2011

Ensembles of numerical model forecasts are of interest to operational early warning forecasters as the spread of the ensemble provides an indication of the uncertainty of the alerts, and the mean value is deemed to outperform the forecasts of the individual models. This paper explores two ensembles on a severe weather episode in Spain, aiming to ascertain the relative usefulness of each one. One ensemble uses sensible choices of physical parameterizations (precipitation microphysics, land surface physics, and cumulus physics) while the other follows a perturbed initial conditions approach. The results show that, depending on the parameterizations, large differences can be expected in terms of storm location, spatial structure of the precipitation field, and rain intensity. It is also found that the spread of the perturbed initial conditions ensemble is smaller than the dispersion due to physical parameterizations. This confirms that in severe weather situations operational forecasts should address moist physics deficiencies to realize the full benefits of the ensemble approach, in addition to optimizing initial conditions. The results also provide insights into differences in simulations arising from ensembles of weather models using several combinations of different physical parameterizations.
A Triangulated Study of Academic Language Needs of Iranian Students of Computer Engineering: Are the Courses on Track?
Authors: Atai Mahmood Reza , Shoja Leila
Published: December 2011

Even though English for Specific Academic Purposes (ESAP) courses constitute a significant part of the Iranian university curriculum, curriculum developers have generally developed the programs based on intuition. This study assessed the present and target situation academic language needs of undergraduate students of computer engineering. To this end, data were elicited from 231 undergraduates, 30 graduate students, 20 computer engineering instructors and 15 ESP instructors at three major Iranian universities. Instrumentation included needs analysis and self-assessment questionnaires, a general English proficiency test, semi-structured interviews, and non-participant observations. Despite some inconsistencies in participants’ perceptions of target situation needs, the findings indicate that written skills and language components are important. The undergraduates perceived difficulties with some sub-skills of reading, writing, speaking, and listening. Moreover, General English Proficiency (GEP) level of the students, as probed by a GEP test and confirmed by self assessment results and teacher assessment data, was generally low. The undergraduates held that they need more general English than highly specific academic English. Finally, participants commented on several major problematic areas. The findings may promise implications for renewing the ESAP course under study and suggest a model framework for needs assessment to other EASP researchers worldwide.
First and second graders’ interpretation of Standard American English morphology across varieties of English
Authors: Beyer Tim , Hudson Kam Carla L
Published: December 2011

While African American English (AAE) and Standard American English (SAE) share many features, there are also differences that could affect comprehension. This article examines how 1st and 2nd grade AAE- and SAE-speaking children interpret sentences containing shared lexical and morphological (i.e., plural –s) forms as compared to sentences containing forms that do not regularly occur in AAE (past tense –ed, 3rd person present –s, future contracted –’ll). Using a picture-choice task the study found that while all children correctly interpreted shared forms, only the SAE-speakers, but not the AAE-speakers, successfully interpreted SAE tense morphology. In addition, the AAE-speakers showed no grade-related changes in performance. This suggests that linguistic differences may impact educational access for AAE-speaking students. These, and other implications, are discussed.
Methodology of Clinical Nutrition Guidelines for Adult Cancer Patients
Authors: van den Berg Tobias , Engelhardt Ellen G. , Haanstra Tsjitske M. , Langius Jacqueline A. E. , van Tulder Maurits W.
Published: December 2011

Background: Malnutrition delays recovery from cancer treatment and can lead to additional serious complications. Clinical guidelines for the management of malnutrition in cancer patients are essential tools for optimizing nutritional care; therefore, their methodological quality is of great importance. This review assesses the methodological quality of international clinical guidelines for the management of malnutrition in adult cancer patients. Methods: Guidelines were identified through searches in multiple electronic databases; afterward, they were systematically reviewed with the AGREE instrument, which is one method of evaluating the methodological quality of guidelines. Results: The methodological quality of the guidelines reviewed varied greatly. The highest scores were observed in the domains “scope and purpose” and “clarity and presentation,” while the lowest scores were awarded in the domains “editorial independence,” “stakeholder involvement,” and “applicability.” Furthermore, there was consensus on the indication for parenteral nutrition and nutrition screening. However, there was a lack of consensus on how nutritional therapy should be provided. No improvement was observed in methodological quality of the more recent guidelines compared to the older ones. Conclusions: The methodological quality of clinical guidelines on malnutrition for cancer patients and the way they are reported need to be improved. To achieve this, developers should utilize available guideline assessment tools, such as the AGREE instrument, when writing or updating guidelines on this topic.
Incidence and Outcomes of Stricture Formation Postlaryngectomy
Authors: Sweeny Larissa , Golden J. Blake , White Hilliary N. , Magnuson J. Scott , Carroll William R. , Rosenthal Eben L.
Published: December 2011

Objective

Postlaryngectomy stricture formation and dysphagia negatively affect quality of life and result in nutritional compromise. Understanding risk factors and successful treatment strategies may improve treatment outcomes.

Study Design

Historical cohort study.

Setting

Tertiary care medical center.

Subjects and Methods

Patients at a tertiary care center who underwent a total laryngectomy between 2003 and 2009 (N = 263) were evaluated in a retrospective manner. Patient demographics, comorbidities, tobacco and alcohol usage, dietary outcomes, feeding tube dependence, and treatment modalities were assessed. Management strategies and outcomes were evaluated.

Results

Strictures developed in 19% (n = 49) of patients, and the majority (82%) occurred in the first year. Incidences of stricture formation were similar for primary (19%) and salvage laryngectomy (19%) patients. Patients undergoing salvage laryngectomy were 2 times more likely to be reconstructed with a free flap, whereas those undergoing a primary laryngectomy were 3 times more likely to be closed primarily. Tubed flap reconstruction significantly increased the incidence of stricture formation compared to primary closure (P =. 02) in salvage laryngectomy cases. In primary laryngectomy patients, stricture formation did not correlate with flap reconstruction (P =. 34) or adjuvant radiation therapy (P =. 79). Patients who required a single dilation had better dietary outcomes compared to patients who required serial dilations (P =. 14). There was no difference in overall disease‐free survival in primary vs salvage laryngectomy patients (P =. 95).

Conclusion

Rates of stricture formation were the same in patients undergoing salvage compared to primary total laryngectomy.