bluuebunny/crossref_metadata_2025 huggingface dataset:
Phytoplankton from Duas Bocas Reservoir, Espírito Santo State, Brazil (except diatoms)
Authors: Delazari-Barroso Alessandra , Sant'Anna Célia Leite , Senna Pedro Américo Cabral
Published: June 2013

Duas Bocas is a small water supply reservoir (0.51 km²) located in a forested area (Duas Bocas Biological Reserve) (20º18'S and 40º28'W). Phytoplankton community was investigated by samplings weekly taken in the dry (July, 1998) and rainy (March 1999) seasons, at surface, euphotic/afotic boundary, and at the bottom of the water column. A total of 76 taxa was identified with the majority of Chlorophyceae (Chlorococcales) (37.3 %), Conjugatophyceae (Desmidiales) (26.7 %), and Cyanobacteria (Chroococcales, Nostocales e Oscillatoriales) (22.7 %). In addition, Euglenophyceae, Dinophyceae, Cryptophyceae, and Chrysophyceae totalized 13.3 %. The predominant genera were Staurastrum, Staurodesmus, Cosmarium, Desmodesmus, Ankistrodesmus, and Monoraphidium. Regarding to the frequency of occurrence, most of the rare and constant species were belong to Chlorophyceae (Chlorococcales) and Conjugatophyceae (Desmidiales) and Cyanobacteria, respectively. According to the literature, most of the species presented cosmopolitan distribution. Among the identified taxa, 44 species (57.9 %) are the first citation for the State of Espírito Santo.
A new species of Alcantarea (E. Morren ex Mez) Harms, Bromeliaceae
Authors: Versieux Leonardo M. , Wanderley Maria das Graças Lapa
Published: June 2013

Alcantarea patriae Versieux & Wand. (Bromeliaceae, Tillandsioideae), a new species from southeastern Brazil, is described and illustrated. It grows on inselbergs within the Atlantic Forest vegetation at Jerônimo Monteiro County, Espírito Santo State. The new taxon shows some morphological similarities with A. odorata (Leme) J.R. Grant, having ligulate long attenuate leaves and sweet scent yellow flowers. However, A. patriae has a very characteristic inflorescence, with the primary bracts shorter than the lateral peduncles, suberect to erect flowering branches (vs. patent to pendulous in A. odorata), with more spaced flowers (20-30 vs. 8-15 mm) and also a wider rosette, up to 1.6 m diam.
Novo método enzimático rápido e sensível de extração e dosagem de amido em materiais vegetais
Authors: Amaral Lourdes Isabel Velho do , Gaspar Marília , Costa Paula Moreira Felix , Aidar Marcos Pereira Marinho , Buckeridge Marcos Silveira
Published: June 2013

Neste trabalho é feita uma comparação entre os métodos mais comumente utilizados para a dosagem de amido em materiais vegetais. A comparação entre um método químico (McCready) e o método enzimático proposto neste trabalho mostra que, embora o primeiro seja apropriado para a maioria dos materiais vegetais, nos casos em que polissacarídeos de parede celular (pectinas e hemiceluloses) estão presentes, os resultados podem ser bastante alterados. Entretanto, ao usar o método enzimático apresentado, foi possível obter estimativas acuradas dos conteúdos de amido de diversos tecidos vegetais. O método proposto neste trabalho é uma opção viável para determinação do conteúdo de amido em diversos tecidos de plantas.
Criptógamos do Parque Estadual das Fontes do Ipiranga, São Paulo, SP: Algas, 24: Zygnemaphyceae (Desmidiales: Octacanthium, Staurastrum e Staurodesmus)
Authors: Bicudo Carlos Eduardo de Matos , Faustino Sílvia Maria Mathes , Godinho Luciana Rufino , Oliveira Marcela
Published: June 2013

Levantamento florístico dos gêneros Octacanthium, Staurastrum e Staurodesmus, da ordem Desmidiales (Zygnemaphyceae) na Reserva Biológica do Parque Estadual das Fontes do Ipiranga situado na cidade de São Paulo, Estado de São Paulo, Brasil. Dezenove espécies de Staurastrum, seis variedades que não são as típicas de suas respectivas espécies e quatro formas igualmente não típicas de suas respectivas variedades; 10 espécies de Staurodesmus, três variedades não típicas e duas formas taxonómicas também não típicas; e duas espécies de Octacanthium foram identificadas, totalizando 45 táxons. Staurastrum tetracerum (Kützing) Ralfs ex Ralfs var. tetracerum f. tetracerum foi a espécie melhor representada do ponto de vista de sua distribuição geográfica, pois ocorreu em cinco localidades no Parque.
Epidendrum secundum Jacq. e E. denticulatum Barb. Rodr. (Orchidaceae): caracteres úteis para a sua delimitação
Authors: Pinheiro Fábio , Barros Fábio de
Published: June 2013

Epidendrum L. é o maior gênero de Orchidaceae na região Neotropical, com cerca de 1.125 espécies. A grande variação que diversas espécies apresentam torna a delimitação do gênero e das próprias espécies um tema bastante controverso. Epidendrum secundum e E. denticulatum são espécies que pertencem à Seção Amphyglottium, a qual inclui algumas das espécies mais variáveis do gênero. Apesar de pertencerem a subseções distintas, devido à morfologia diversa do calo do labelo, são espécies que apresentam muitas semelhanças, no porte geral e morfologia das plantas e na coloração das flores. Como em muitos materiais de herbário a visualização do calo do labelo é difícil, esta semelhança entre as espécies tem gerado diversas identificações trocadas, tanto em herbários quanto em plantas vivas. O objetivo deste trabalho é selecionar um conjunto de caracteres que possa ser utilizado para uma identificação mais precisa dos registros de E. secundum e E. denticulatum. Foram amostrados 30 indivíduos de E. secundum e 26 de E. denticulatum mantidos em cultivo na Seção de Orquidário do Instituto de Botânica de São Paulo, e destes indivíduos foram medidos 20 caracteres quantitativos. Foram empregados métodos de análise multivariada (PCA, UPGMA, DA e Box-Plot) e o Teste t de Student, corrigido pelo critério de Bonferroni. Foram encontrados seis caracteres florais que possuem uma diferença significativa entre E. secundum e E. denticulatum, revelando que técnicas de morfometria podem ser bastante úteis para a delimitação de espécies amplamente variáveis, de difícil circunscrição. É fornecida uma chave para separação entre E. secundum e E. denticulatum.
Nanobiotechnology of protein-based compartments: steps toward nanofactories
Authors: Schreiber Andreas , Schiller Stefan M.
Published: June 2013

Nanobiotechnology of toroids/donuts, yoctowells, tubes, cages, capsids, compartments and organelles based on protein-building blocks allows for the definition of precise reaction spaces in vitro and in vivo. Utilizing a synthetic biology approach, the generation of compartment-forming protein ‘bio-bricks’ points toward new ways to control the assembly of these structures to develop nanofactories in vivo. This is envisioned to be an important step allowing for the precise assembly of novel metabolic cascades within nanoreactors in the future. The ability to site-selectively modify proteins by inserting or replacing selected natural and unnatural amino acids at defined positions, provides the necessary tools to control novel functions via ‘genetic programming’. The protein-building blocks, already embedded in nature's nanocompartment tool box, will be the focus of this review. The various protein structures forming compartments in vitro and in vivo will be presented together with their current applications.
Integration of indium micromirrors for biosensing applications
Authors: Bule Rafael Gomez , Cervera Raul Broto , Hsiao Chun-Mou , Perez-Castillejos Raquel
Published: June 2013

Metallic mirrors are important components of opto-microfluidic systems for their ability to reflect light. Their use, however, has been limited by the challenges of their integration to microfluidic devices. Here the authors describe the fabrication of indium micromirrors integrated to microfluidic devices and successfully demonstrate their application to the determination of fluorescein concentration in aqueous solutions by absorbance measurements. The technological route presented here for integrating metallic mirrors to microfluidic devices is fast, simple and inexpensive.
Waynergy people: a new pavement energy harvest system
Authors: Duarte Francisco , Casimiro Filipe , Correia Diogo , Mendes Rui , Ferreira Adelino
Published: June 2013

This paper describes a new pavement energy harvest system developed in Portugal by the Waydip Company with the collaboration of the pavement mechanics laboratory of the University of Coimbra. The electric energy generated by the Waynergy system for people during 1 h was 525 J or 0·15 W·h. It is expected that the Waynergy system for vehicles could generate substantial electrical energy, which can be used not only to charge batteries for electric vehicles, but also for general consumption through injection into the electricity grid or direct use in electrical equipment, such as traffic lights, public lighting and outdoor advertising.
Briefing: Public sector contribution to resource recovery in the UK
Authors: Greenfield David W.J.
Published: June 2013

Local government manages over 30 Mt of waste per annum in the UK. Much of that waste is composed of resources that may hold a potential for impacting material security of the UK. A critique of the current and future scenarios is presented with the introduction of a matrix for supporting planning for new collection and treatment methodologies for consideration and future development.
Genetic consequences of historical anthropogenic and ecological events on giant pandas
Authors: Zhu Lifeng , Hu Yibo , Qi Dunwu , Wu Hua , Zhan Xiangjiang , Zhang Zhejun , Bruford Michael W. , Wang Jinliang , Yang Xuyu , Gu Xiaodong , Zhang Lei , Zhang Baowei , Zhang Shanning , Wei Fuwen
Published: June 2013

The giant panda (Ailuropoda melanoleuca) was taken to the brink of extinction in the 1980s through a combination of deforestation, large‐scale loss of bamboo in the core of its range, poaching, and zoo collection, causing over 1000 deaths from the 1950s. It was thought that the drastic population decline was likely to impose a severe impact on population viability. Here, based on temporal genotyping of individuals, we show that this rapid decline did not significantly reduce the overall effective population size and genetic variation of this species, or of the two focal populations (Minshan and Qionglai) that declined the most. These results are contrary to previously assumptions, probably because the population decline has not produced the expected negative impact due to the short time scale involved (at most 10 generations), or because previous surveys underestimated the population size at the time of decline. However, if present‐day habitat fragmentation and limited migration of giant pandas remains, we predict a loss of genetic diversity across the giant pandas' range in the near future. Thus, our findings highlight the substantial resilience of this species when facing demographic and environmental stochasticity, but key conservation strategies, such as enhancing habitat connectivity and habitat restoration should be immediately implemented to retain the extant genetic variation and maintain long‐term evolutionary potential of this endangered species.
Analysis of Production History for Unconventional Gas Reservoirs With Statistical Methods
Authors: Bhattacharya Srimoyee , Nikolaou Michael
Published: June 2013

Unconventional gas resources have dramatically changed the future energy landscape. Developing these resources involves substantial risk. Such risk can be mitigated if information gathered at initial stages of the development of a field is used efficiently and effectively to guide future development. A variety of tools—such as decline-curve analysis (DCA), type-curve analysis, simulator history matching, and artificial intelligence (AI)—is used to that effect. These tools accomplish partially overlapping but different tasks. Additional tools that could not only facilitate the analysis of historical data but also guide future development would be of value. In this work, we propose an efficient methodology that can use historical production data from existing wells to answer questions such as the following: Which wells will behave similarly? Which wells will behave differently from each other or from standard expectations? Which factors will contribute to these differences? How can data from existing wells be used to anticipate the performance of new wells? The proposed methodology relies on standard principal-component analysis (PCA) and principal-component regression (PCR). The application of PCA to historical production data from twelve wells in the Holly Branch field quickly identified wells with distinct behavior. The subsequent investigation of pressure and the completion data for these wells revealed reasons for such distinct behavior. Finally, a simple linear model was built with PCR, with good ability to predict production from new wells, as assessed through cross-validation. The value of the efficiency offered by the proposed methodology would be much higher for larger data sets, for which manual analysis of production data is more cumbersome.
Investigation and Prediction of High-Viscosity Liquid Effect on Two-Phase Slug Length in Horizontal Pipelines
Authors: Al-Safran E.M.. M. , Gokcal B.. , Sarica C..
Published: June 2013

The recent trend of increasing energy demand led the industry toward the development of heavy oil unconventional resources. However, the production and transportation of such heavy oil is a challenge because of the lack of understanding of two-phase flow behavior under the condition of high-viscosity liquid phase. The objective of this study is to physically understand the effect of liquid viscosity on slug length and develop an empirical two-phase slug-length correlation for high oil viscosity. The developed slug length correlation can improve the existing two-phase flow models often used in the development and maintenance of heavy-oil fields.

Experimental high-viscosity (0.181–0.589 Pa.s) two-phase air/ mineral viscous oil slug-length data is acquired in a horizontal 0.0508-m ID pipe. High-speed recorded flow visualization revealed the effect of liquid-phase viscosity on the scooping and shedding processes at the slug front and back, respectively, and liquid film thickness in the Taylor bubble zone. Data analysis showed a one-third reduction in high viscosity (0.181–0.589 Pa.s) average slug length compared with low viscosity (0.001–0.017 Pa.s) average slug length. Furthermore, analysis of slug-length distributions revealed that as liquid viscosity increases, slug length distribution deviates from the log-normal distribution to a trancated positively skewed distribution. As a result, the average, the variance, and maximum slug-length values vary with liquid viscosity. On the basis of these experimental observations, a physical model is proposed which suggests that the thick liquid film in the Taylor bubble zone and the short slug-mixing zone at the slug front result in a fully developed velocity profile at the slug back, stabilizing the slug at a shorter length. A new dimensional-analysis-based empirical model is proposed to predict dimensionless average slug length for high-viscosity liquid slug flow. A validation and comparison study of the proposed correlation showed the best performance among the existing correlations.
Effect of valence of copper on adsorption of dimethyl sulfide from liquid hydrocarbon streams on activated bentonite
Authors: Huang Huan , Yi De-Zhi , Lu Yan-Nan , Wu Xiao-Lin , Bai Yun-Peng , Meng Xuan , Shi Li
Published: June 2013

Samples of activated bentonite and activated bentonite modified with CuCl and CuCl2, separately, were tested as dimethyl sulfide (DMS) adsorbents. The adsorption and desorption behaviours of DMS on the adsorbents were studied systematically. The adsorbents were characterised by nitrogen adsorption, XRD, and DMS-TPD tests. The addition of CuCl and CuCl2 to the activated carbon significantly enhanced the adsorption capacity of DMS, despite a notable decrease in the specific surface area and total pore volume of the activated bentonite. It is presumed that copper cation species may act as an adsorption site for DMS. The adsorption capacity of Cu(II)-bentonite was better than that of Cu(I)-bentonite. The DMS-TPD patterns indicate that the stronger electrophilicity of Cu(II) compared to that of Cu(I) caused it to interact with the DMS molecules more strongly, thus contributing to a better adsorptive performance. The Cu(II)-bentonite calcined at 150°C had the best DMS removal performance with a high sulphur capacity of 70.56 mg S g−1 adsorbent. The DMS removal performance became much lower with the increase in the calcination temperature, which appeared to be due to the decrease in the CuCl2·2H2O phase and the formation of the monoclinic Cu(OH)Cl phase.
Kinetics of chloride substitution in [Pt(bpma)Cl]+ and [Pt(gly-met-S,N,N)Cl] complexes by thiourea, nitrites, and iodides
Authors: Topolski Adrian , Bugarčić Živadin
Published: June 2013

Substitution of chloride in [PtCl(bpma)]+ and [PtCl(gly-met-S,N,N)], where bpma is bis(2-pyridylmethyl)amine and gly-met-S,N,N is glycyl-l-methionine, was studied as a function of the entering nucleophile concentration and temperature. Reactions between the platinum(II) complexes and thiourea (TU), iodides (I−), and nitrites(III) (NO2−) were carried out in aqueous solutions using conventional UV-VIS spectrophotometry. Suitable ionic conditions were reached by an addition of 0.1 M NaClO4 and 0.01 M NaCl (to suppress hydrolysis). The second-order rate constants, k 2, for the studied reactions with NO2− varied between 0.036–0.038 M−1 s−1, and for the reactions with TU between 0.095–1.06 M−1 s−1, respectively. The reaction between TU and the [PtCl(bpma)]+ ion is ten times faster than that of the [PtCl(gly-met-S,N,N)] complex. An analysis of the activation parameters, ΔH ≠ and ΔS ≠, for the selected reactions clearly shows their associative nature.
Performance and lifetime of slurry packed capillary columns for high performance liquid chromatography
Authors: Franc Martin , Vojta Jiří , Sobotníková Jana , Coufal Pavel , Bosáková Zuzana
Published: June 2013

Fused silica capillary columns of the internal diameter of 320 μm were packed with the Nucleosil C18 stationary phase of 5 μm using the slurry packing method. The time of the bed compaction phase, packing pressure, and the use of ultrasound varied to study their influence on the column performance. Van Deemter curves were measured and separation impedance values were calculated in order to assess both separation efficiency and kinetic performance of the columns. Selected columns were tested again after nine months to evaluate the stability of their beds. Separation efficiencies of all columns were similar, but a major difference, caused by the use of ultrasound, was observed in the bed stability. Columns sonicated for 25 minutes during the bed compaction phase exhibited unchanged performance in the course of several months, while the performance of non-sonicated columns decreased.
Transposable elements occur more frequently in autism-risk genes: Implications for the role of genomic instability in autism
Authors: Williams Emily , Casanova Manuel , Switala Andrew , Li Hong , Qiu Mengsheng
Published: June 2013

An extremely large number of genes have been associated with autism. The functions of these genes span numerous domains and prove challenging in the search for commonalities underlying the conditions. In this study, we instead looked at characteristics of the genes themselves, specifically in the nature of their transposable element content. Utilizing available sequence databases, we compared occurrence of transposons in autismrisk genes to randomized controls and found that transposable content was significantly greater in our autism group. These results suggest a relationship between transposable element content and autism-risk genes and have implications for the stability of those genomic regions.
Untangling the role of tau in Alzheimer’s disease: A unifying hypothesis
Authors: Bhatia Neha , Hall Garth
Published: June 2013

Recent investigations into the etiology and pathogenesis of Alzheimer’s disease (AD) in the past few years have expanded to include previously unexplored and/or disconnected aspects of AD and related conditions at both the cellular and systemic levels of organization. These include how AD-associated abnormalities affect the cell cycle and neuronal differentiation state and how they recruit signal transduction, membrane trafficking and protein transcytosis mechanisms to produce a neurotoxic syndrome capable of spreading itself throughout the brain. The recent expansion of AD research into intercellular and new aspects of cellular degenerative mechanisms is causing a systemic re-evaluation of AD pathogenesis, including the roles played by well-studied elements, such as the generation of Aβ and tau protein aggregates. It is also changing our view of neurodegenerative diseases as a whole. Here we propose a conceptual framework to account for some of the emerging aspects of the role of tau in AD pathogenesis.
Synaptic plasticity studies and their applicability in mouse models of neurodegenerative diseases
Authors: Gruart Agnès , Madroñal Noelia , Jurado-Parras María , Delgado-García José
Published: June 2013

During the past few years, there have been many important contributions to the better understanding of the different types of memory and the putative neural structures that generate them. Moreover, various studies on neurodegenerative diseases in human beings have added useful information about learning and memory formation, and about their loss in patients with these disabling diseases. The development of sophisticated pharmacogenetic tools applied to mouse models, reproducing different types of neurodegenerative disease or, at least, some of their main symptoms, has turned out to be extremely useful for the further development of contemporary neuroscience. In addition, ingenious behavioral and electrophysiological approaches have been developed to study the activity-dependent changes in synaptic strength during learning and memory processes in the best possible way — that is, in the alert behaving animal. Collected data from these numerous studies have enabled us to know more about the role of many different molecular components integrating the synaptic cleft, and to draw some conclusions about the concordance between in vitro and in vivo recorded data, and the generalization of the results to other types of learning and/or brain-related structures. As described here, changes in synaptic strength studied in key neural synapses during learning and memory processes in genetically manipulated mice can represent an interesting and powerful approach to the better understanding of neural processes underlying the acquisition of new motor and cognitive abilities and how they are affected by different human diseases involving the neural tissue.
Non-invasive brain stimulation in children: Applications and future directions
Authors: Rajapakse Thilinie , Kirton Adam
Published: June 2013

Transcranial magnetic stimulation (TMS) is a neurostimulation and neuromodulation technique that has provided over two decades of data in focal, non-invasive brain stimulation based on the principles of electromagnetic induction. Its minimal risk, excellent tolerability and increasingly sophisticated ability to interrogate neurophysiology and plasticity make it an enviable technology for use in pediatric research with future extension into therapeutic trials. While adult trials show promise in using TMS as a novel, non-invasive, non-pharmacologic diagnostic and therapeutic tool in a variety of nervous system disorders, its use in children is only just emerging. TMS represents an exciting advancement to better understand and improve outcomes from disorders of the developing brain.
Astrocytes: Emerging stars in leukodystrophy pathogenesis
Authors: Lanciotti Angela , Brignone Maria , Bertini Enrico , Petrucci Tamara , Aloisi Francesca , Ambrosini Elena
Published: June 2013

Astrocytes are the predominant glial cell population in the central nervous system (CNS). Once considered only passive scaffolding elements, astrocytes are now recognised as cells playing essential roles in CNS development and function. They control extracellular water and ion homeostasis, provide substrates for energy metabolism, and regulate neurogenesis, myelination and synaptic transmission. Due to these multiple activities astrocytes have been implicated in almost all brain pathologies, contributing to various aspects of disease initiation, progression and resolution. Evidence is emerging that astrocyte dysfunction can be the direct cause of neurodegeneration, as shown in Alexander’s disease where myelin degeneration is caused by mutations in the gene encoding the astrocyte-specific cytoskeleton protein glial fibrillary acidic protein. Recent studies point to a primary role for astrocytes in the pathogenesis of other genetic leukodystrophies such as megalencephalic leukoencephalopathy with subcortical cysts and vanishing white matter disease. The aim of this review is to summarize current knowledge of the pathophysiological role of astrocytes focusing on their contribution to the development of the above mentioned leukodystrophies and on new perspectives for the treatment of neurological disorders.
Neurobiological aspects of suicide and suicide attempts in bipolar disorder
Authors: Mathews Daniel , Richards Erica , Niciu Mark , Ionescu Dawn , Rasimas Joseph , Zarate Carlos
Published: June 2013

Suicide and bipolar disorder (BD) are challenging, complex, and intertwined areas of study in contemporary psychiatry. Indeed, BD is associated with the highest lifetime risk for suicide attempt and completion of all the psychiatric conditions. Given that several clinical risk factors for both suicide and BD have been well noted in the literature, exploring the neurobiological aspects of suicide in BD may provide insights into both preventive measures and future novel treatments. This review synthesizes findings regarding the neurobiological aspects of suicide and, when applicable, their link to BD. Neurochemical findings, genes/epigenetics, and potential molecular targets for current or future treatments are discussed. The role of endophenotypes and related proximal and distal risk factors underlying suicidal behavior are also explored. Lastly, we discuss the manner in which preclinical work on aggression and impulsivity may provide additional insights for the future development of novel treatments.
Comparison of two commercial enzyme-linked immunosorbent assays for cerebrospinal fluid measurement of amyloid β1–42 and total tau
Authors: Babić Mirjana , Vogrinc Željka , Diana Andrea , Klepac Nataša , Borovečki Fran , Hof Patrick , Šimić Goran
Published: June 2013

Amyloid β1–42 (Aβ1–42), total tau (t-tau), and phosphorylated tau (p-tau) are the main cerebrospinal fluid (CSF) biomarkers for early diagnosis of Alzheimer’s disease (AD). Detection of AD is critically important in view of the growing number of potential new drugs that may influence the course of the disease in its early phases. However, cut-off levels for these CSF biomarkers have not yet been established. Variability in absolute concentrations of AD biomarkers is high among studies and significant differences were noticed even within the same datasets. Variability in biomarkers levels in these assays may be due to many aspects of operating procedures. Standardization of pre-analytical and analytical procedures in collection, treatment, and storage of CSF samples is crucial because differences in sample handling can drastically influence results. Multicenter studies showed that usage of ELISA kits from different manufacturers also affects outcome. So far only very few studies tested the efficiency of ELISA kits produced by different vendors. In this study, the performance of Innogenetics (Gent, Belgium) and Invitrogen (Camarillo, CA, USA) ELISA kits for t-tau and Aβ1–42 was tested. Passing-Bablok analysis showed significant differences between Invitrogen and Innogenetics ELISA methods, making it impossible to use them interchangeably.
Practice Patterns of Canadian Physiotherapists Mobilizing Patients with External Ventricular Drains
Authors: Hale Chelsea , Wong Kyle , Pennings Amanda , Rnic Amanda , Tobali Benjamin , Hawke Christopher , Brown Jean , Cott Cheryl , Heck Carol , Duncan Catharine
Published: June 2013

Purpose: To describe current mobilization practices of Canadian physiotherapists when treating patients with external ventricular drains (EVDs). Methods: A quantitative, descriptive, cross-sectional study design using an online questionnaire via SurveyMonkey. An email invitation and questionnaire link was distributed in March 2010 to physiotherapists currently working with this patient population in Neurosurgical Centres across Canada. Results: Respondents were 25 physiotherapists (21 full-time, 2 part-time, and 2 who did not disclose work status) working in 5 different provinces who treated ≥1 patient/month with an EVD (n=9). Slightly more than half of respondents had ≤10 years' clinical physiotherapy experience (n=14); the remainder had >10 years' experience (n=11). The majority of respondents indicated that they felt comfortable mobilizing patients with EVDs (n =19) and that it was safe to do so (n=20). Clinical experience (n=23) and safety concerns (n=25) were most commonly cited as guiding practice. More experienced physiotherapists were more likely to use out-of-bed mobilization practices. Regardless of experience, the majority of physiotherapists (20/25) ranked intracranial pressure (ICP) as the most important factor and saturation of oxygen (Spo2) as the least important factor to consider before mobilization. Conclusions: Canadian physiotherapists are mobilizing patients with EVDs, and the intensity level of their mobilization practices appears to be related to their experience level. Data from the current study may be used in developing future best-practice guidelines for the mobilization of patients with EVDs.
Analysis of Electric Fields inside Microchannels and Single Cell Electrical Lysis with a Microfluidic Device
Authors: Morshed Bashir , Shams Maitham , Mussivand Tofy
Published: June 2013

Analysis of electric fields generated inside the microchannels of a microfluidic device for electrical lysis of biological cells along with experimental verification are presented. Electrical lysis is the complete disintegration of cell membranes, due to a critical level of electric fields applied for a critical duration on a biological cell. Generating an electric field inside a microchannel of a microfluidic device has many advantages, including the efficient utilization of energy and low-current requirement. An ideal microchannel model was compared with a practical microchannel model using a finite element analysis tool that suggests that the overestimation error can be over 10%, from 2.5 mm or smaller, in the length of a microchannel. Two analytical forms are proposed to reduce this overestimation error. Experimental results showed that the high electric field is confined only inside the microchannel that is in agreement with the simulation results. Single cell electrical lysis was conducted with a fabricated microfluidic device. An average of 800 V for seven seconds across an 8 mm-long microchannel with the dimension of 100 μm × 20 μm was required for lysis, with electric fields exceeding 100 kV/m and consuming 300 mW.
Isotope Effects in ESR Spectroscopy
Authors: Stößer Reinhard , Herrmann Werner
Published: June 2013

In order to present the relationship between ESR spectroscopy and isotope effects three levels are considered: (i) ESR spectroscopy is described on a general level up to the models for interpretation of the experimental spectra, which go beyond the usually used time and mass independent spin-Hamilton operator, (ii) the main characteristics of the generalized isotope effects are worked out, and finally (iii) the basic, mainly quantum mechanical effects are used to describe the coupling of electron spins with the degrees of freedom, which are accessible under the selected conditions, of the respective paramagnetic object under investigation. The ESR parameters and the respective models are formalized so far, that they include the time and mass depending influences and reflect the specific isotope effects. Relations will be established between the effects in ESR spectra to spin relaxation, to spin exchange, to the magnetic isotope effect, to the Jahn-Teller effects, as well as to the influence of zero-point vibrations. Examples will be presented which demonstrate the influence of isotopes as well as the kind of accessible information. It will be differentiated with respect to isotope effects in paramagnetic centres itself and in the respective matrices up to the technique of ESR imaging. It is shown that the use of isotope effects is indispensable in ESR spectroscopy.
The Role of Viscosity and Fermentability of Dietary Fibers on Satiety- and Adiposity-Related Hormones in Rats
Authors: Schroeder Natalia , Marquart Len , Gallaher Daniel
Published: June 2013

Dietary fiber may contribute to satiety. This study examined the effect of two dietary fiber characteristics, small intestinal contents viscosity and large intestinal fermentability, on satiety-and adiposity-related hormones in rats. Diets contained fiber sources that were non-viscous, somewhat viscous, or highly viscous, and either highly fermentable or non-fermentable, in a 2 × 3 factorial design. In the fed state (2 h postprandial), rats fed non-fermentable fibers had significantly greater plasma GLP-1 concentration than fermentable fibers. In the fasted state, among non-fermentable fibers, viscosity had no effect on GLP-1 concentration. However, among fermentable fibers, greater viscosity reduced GLP-1 concentration. Plasma peptide tyrosine tyrosine (PYY) concentrations in the fasted state were not influenced by the fermentability of the fiber overall, however animals consuming a fructooligosaccharide greater PYY concentration. In both the fed and fasted states, rats fed non-fermentable fibers had a significantly lower plasma ghrelin concentration than rats fed fermentable fibers. In the fasted state, rats fed non-fermentable fibers had a significantly lower plasma leptin concentration than rats fed fermentable fibers. Thus, fermentability and viscosity of dietary fiber interacted in complex ways to influence satiety- and adiposity-related plasma hormone concentrations. However, the results suggest that highly viscous, non-fermentable fibers may limit weight gain and reduce adiposity and non-fermentable fibers, regardless of viscosity, may promote meal termination.
Vitamin D Levels Are Associated with Cardiac Autonomic Activity in Healthy Humans
Authors: Mann Michelle , Exner Derek , Hemmelgarn Brenda , Sola Darlene , Turin Tanvir , Ellis Linda , Ahmed Sofia
Published: June 2013

Vitamin D deficiency (≤50nmol/L 25-hydroxy vitamin D) is a cardiovascular (CV) risk factor that affects approximately one billion people worldwide, particularly those affected by chronic kidney disease (CKD). Individuals with CKD demonstrate abnormal cardiac autonomic nervous system activity, which has been linked to the significant rates of CV-related mortality in this population. Whether vitamin D deficiency has a direct association with regulation of cardiac autonomic activity has never been explored in humans. Methods: Thirty-four (34) healthy, normotensive subjects were studied and categorized based on 25-hydroxy vitamin D deficiency (deficient vs. non-deficient, n = 7 vs. 27), as well as 1,25-dihydroxy vitamin D levels (above vs. below 25th percentile, n = 8 vs. 26). Power spectral analysis of electrocardiogram recordings provided measures of cardiac autonomic activity across low frequency (LF) and high frequency (HF, representative of vagal contribution) bands, representative of the sympathetic and vagal limbs of the autonomic nervous system when transformed to normalized units (nu), respectively, as well as overall cardiosympathovagal balance (LF:HF) during graded angiotensin II (AngII) challenge (3 ng/kg/min × 30 min, 6 ng/kg/min × 30 min). Results: At baseline, significant suppression of sympathovagal balance was observed in the 25-hydroxy vitamin D-deficient participants (LF:HF, p = 0.02 vs. non-deficient), although no other differences were observed throughout AngII challenge. Participants in the lowest 1,25-dihydroxy VD quartile experienced significant withdrawal of inhibitory vagal control, as well as altered overall sympathovagal balance throughout AngII challenge (HF, mean difference = −6.98 ± 3 nu, p = 0.05; LF:HF, mean difference = 0.34 ± 0.1, p = 0.043 vs. above 25th percentile). Conclusions: Vitamin D deficiency is associated with suppression of resting cardiac autonomic activity, while low 1,25-dihydroxy vitamin D levels are associated with unfavourable cardiac autonomic activity during an acute AngII stressor, offering a potential pathophysiological mechanism that may be acting to elevate CV risk in in populations with low vitamin D status.
Direct Electrochemistry of Hemoglobin at a Graphene Gold Nanoparticle Composite Film for Nitric Oxide Biosensing
Authors: Xu Miao-Qing , Wu Jian-Feng , Zhao Guang-Chao
Published: June 2013

A simple two-step method was employed for preparing nano-sized gold nanoparticles-graphene composite to construct a GNPs-GR-SDS modified electrode. Hemoglobin (Hb) was successfully immobilized on the surface of a basal plane graphite (BPG) electrode through a simple dropping technique. Direct electrochemistry and electrocatalysis of the hemoglobin-modified electrode was investigated. The as-prepared composites showed an obvious promotion of the direct electro-transfer between hemoglobin and the electrode. A couple of well-defined and quasi-reversible Hb CV peaks can be observed in a phosphate buffer solution (pH 7.0). The separation of anodic and cathodic peak potentials is 81 mV, indicating a fast electron transfer reaction. The experimental results also clarified that the immobilized Hb retained its biological activity for the catalysis toward NO. The biosensor showed high sensitivity and fast response upon the addition of NO, under the conditions of pH 7.0, potential ‒0.82 V. The time to reach the stable-state current was less than 3 s, and the linear response range of NO was 0.72–7.92 μM, with a correlation coefﬁcient of 0.9991.
Altered precipitation affects plant hybrids differently than their parental species
Authors: Campbell Diane R. , Wendlandt Camille
Published: June 2013

• Premise of the study: Future changes in environmental conditions may alter evolutionary processes, including hybridization in nature. Frequency of hybrids could be altered via range shifts by the parental species or by changes in prezygotic or postzygotic reproductive isolation. We examined the potential for range shifts and change in postzygotic isolation by determining effects of increasing and decreasing precipitation on leaf physiology and fitness components in the subalpine herbs Ipomopsis aggregata (Polemoniaceae), I. tenuituba¸ and their natural hybrids in a common garden in the habitat of I. aggregata.

• Methods: Summer precipitation was experimentally doubled or halved over 3 yr in comparison with ambient conditions. We measured relative growth rate, specific leaf area, intrinsic water‐use efficiency, survival to reproduction, biomass, number of flowers produced, and floral morphology.

• Key results: Ipomopsis tenuituba increased relative growth rate with higher precipitation more so than did I. aggregata during the first summer, but this response did not result in changes across treatments in relative survival or final reproductive success of the two species. When precipitation was reduced, the relative success of hybrids was greater than that of the home species, I. aggregata. In dry conditions, hybrids increased water‐use efficiency and fitness as indexed by number of flowers more so than the other plant types did.

• Conclusions: Increased reproduction in hybrids in the reduced precipitation regime indicates that postzygotic reproductive isolation may breakdown under imposition of dry conditions. These results suggest the potential for frequency of hybrids to increase if severe droughts become more common.
Entre représentation institutionnelle et action collective : la variété des pratiques syndicales dans un centre d'appels
Authors: Mazières-Vaysse Adrien
Published: June 2013

Cet article interroge, à travers l’étude de l’action syndicale dans une entreprise de centres d’appels, la manière dont se manifeste, dans un secteur d’activité précarisé, l’injonction contemporaine à davantage de démocratie participative. Il montre la mise en œuvre d’un mode d’action syndicale qui articule représentation syndicale des salariés par les élus dans les Institutions Représentatives du Personnel et action collective. Cette configuration spécifique permet la constitution d’un espace de participation qui, au-delà des seuls syndicalistes, favorise l’intervention des salariés dans l’entreprise et la délibération au sein du collectif de travail.
Convaincre ou produire ? Genèse et formes de participation ouvrière dans une usine « récupérée » d'Argentine
Authors: Quijoux Maxime
Published: June 2013

La multiplication d’espaces de délibération dans l’entreprise favorise-t-elle nécessairement une meilleure répartition du pouvoir ? À partir de l’examen d’une usine « récupérée » par les salariés en Argentine, cet article vise à montrer que la démocratisation d’un lieu de travail est tributaire de sources de légitimité, notamment issues de l’atelier, qui peuvent entrer en concurrence avec les pratiques habituelles de démocratie directe. Cet article met alors en lumière une nouvelle forme de bureaucratisation fondée sur un régime où prévalent des conduites et valeurs « disciplinaires », telles que l’assiduité, la ponctualité et la productivité.
La participation aux décisions stratégiques de l'entreprise : influence ou pouvoir des administrateurs salariés ?
Authors: Conchon Aline
Published: June 2013

L’institutionnalisation de la représentation des travailleurs avec droit de vote dans les conseils d’administration ou de surveillance visait, comme tout projet de démocratisation de l’entreprise, à un rééquilibrage des pouvoirs. L’analyse des représentations des administrateurs salariés au prisme du concept de participation aux décisions tel qu’entendu en sociologie des relations professionnelles donne à voir une tout autre réalité. Plutôt que de pouvoir, ces acteurs se trouvent limités à une capacité d’influence en situation de délibération imparfaite en conséquence du poids d’un autre acteur, l’actionnaire.
Réviser l'« espace public » avec la sociologie. Un regard sur la théorie de Bernhard Peters
Authors: Aubert Isabelle
Published: June 2013

Introduite par Jürgen Habermas en 1962, la notion d’espace public a contribué à la formation d’un courant théorique sur la démocratie délibérative. Avec le temps, les critiques qu’on lui a adressées ont prévalu sur son usage, car elle est le plus souvent écartée aujourd’hui. L’article s’intéresse aux recherches qu’a menées le sociologue allemand Bernhard Peters en théorie normative et en sociologie empirique au sujet du sens que peut avoir, compte tenu de ces critiques, l’espace public aujourd’hui. Mettant en lumière sa fonction en théorie politique puis enquêtant dans le détail sur la réalité des espaces publics contemporains et sur leurs extensions (nationale ou transnationale ?), Peters ouvre la voie à une réflexion sur la démocratie qui met en son centre une approche révisée et critique de l’espace public.
T Cell Activation Threshold Regulated by E3 Ubiquitin Ligase Cbl-b Determines Fate of Inducible Regulatory T Cells
Authors: Qiao Guilin , Zhao Yixia , Li Zhenping , Tang Peter Q. , Langdon Wallace Y. , Yang Tianlan , Zhang Jian
Published: June 2013

E3 ubiquitin ligase Casitas–B-lineage lymphoma protein-b (Cbl-b) is critical for establishing the threshold for T cell activation and is essential for induction of T cell anergy. Recent studies suggest that Cbl-b is involved in the development of CD4+CD25+ inducible regulatory T cells (iTregs). In this study, we report that the optimal induction of Foxp3 by naive CD4+CD25− T cells requires suboptimal TCR triggering. In the absence of Cbl-b, the TCR strength for optimal Foxp3 induction is downregulated in vitro. Using TCR-transgenic Rag−/− mice in combination with Cbl-b deficiency, we show that in vivo iTreg development is also controlled by Cbl-b via tuning the TCR strength. Furthermore, we show that Akt-2 but not Akt-1 regulates Foxp3 expression downstream of Cbl-b. Therefore, we demonstrate that Cbl-b regulates the fate of iTregs via controlling the threshold for T cell activation.
HLA Peptide Length Preferences Control CD8+ T Cell Responses
Authors: Rist Melissa J. , Theodossis Alex , Croft Nathan P. , Neller Michelle A. , Welland Andrew , Chen Zhenjun , Sullivan Lucy C. , Burrows Jacqueline M. , Miles John J. , Brennan Rebekah M. , Gras Stephanie , Khanna Rajiv , Brooks Andrew G. , McCluskey James , Purcell Anthony W. , Rossjohn Jamie , Burrows Scott R.
Published: June 2013

Class I HLAs generally present peptides of 8–10 aa in length, although it is unclear whether peptide length preferences are affected by HLA polymorphism. In this study, we investigated the CD8+ T cell response to the BZLF1 Ag of EBV, which includes overlapping sequences of different size that nevertheless conform to the binding motif of the large and abundant HLA-B*44 supertype. Whereas HLA-B*18:01+ individuals responded strongly and exclusively to the octamer peptide 173SELEIKRY180, HLA-B*44:03+ individuals responded to the atypically large dodecamer peptide 169EECDSELEIKRY180, which encompasses the octamer peptide. Moreover, the octamer peptide bound more stably to HLA-B*18:01 than did the dodecamer peptide, whereas, conversely, HLA-B*44:03 bound only the longer peptide. Furthermore, crystal structures of these viral peptide–HLA complexes showed that the Ag-binding cleft of HLA-B*18:01 was more ideally suited to bind shorter peptides, whereas HLA-B*44:03 exhibited characteristics that favored the presentation of longer peptides. Mass spectrometric identification of > 1000 naturally presented ligands revealed that HLA-B*18:01 was more biased toward presenting shorter peptides than was HLA-B*44:03. Collectively, these data highlight a mechanism through which polymorphism within an HLA class I supertype can diversify determinant selection and immune responses by varying peptide length preferences.