bluuebunny/crossref_metadata_2025 huggingface dataset:
Current Role of Prostatic Transrectal Ultrasound in the Diagnosis of PCa
Authors: Soggia Paolo , Madonia Massimo , Corbu Carlo
Published: March 2012

Introduction

Cancer of the prostate (PCa) is now recognized as one of the most important medical problems facing the male population. In Europe, PCa is the most common solid neoplasm, with an incidence rate of 214 cases per 1000 men, outnumbering lung and colorectal cancer (1). According to the EAU guidelines, the main diagnostic tools to obtain evidence of PCa include DRE, serum concentration of PSA and transrectal ultrasonography (TRUS). But, does TRUS affect the diagnostic process?

Material and Methods

Between March 2007 and March 2011 we performed 441 prostate biopsies to compare the results with clinical, laboratory and ultrasonographic features of every patient. We investigated sensitivity, specificity, accuracy, positive and negative predictive value and likelihood ratio about every diagnostic tool (PSA, DRE and TRUS).

Results

The transrectal ultrasonographyhas a low diagnostic accuracy for prostate cancer because it shows: low sensitivity and specificity (higher incidence of false positives than true positives); variability of ultrasound situations within which the tumor occurs.

Conclusions

In our opinion TRUS may be considered only a complement to PSA and DRE.
Reading W.G. Sebald with Alberto Giacometti
Authors: Matthews Timothy
Published: March 2012

Where is Alberto Giacometti? The question seems to arise materially from an engagement with his art and the invitations it seems to extend. Much of his art is a life-long exploration of visual representation itself, of the attempt to visualise objects in a two or threedimensional space; to place people in space. But that placing is elusive, and the places seem to dissolve, making Giacometti’s idiom at once unique and beyond reach, perhaps even untouchable – and this from the creator of such tactile-looking pieces. One way of accepting this invitation to engage with an art that wonders how anything can be engaged with is to ask what it can tell us about the art of others. In this essay, I want to see what the art of Sebald can tell me about the art of Giacometti.
Poetry of Squalor: Exploring the Borgata in Pier Paolo Pasolini's Accattone
Authors: Ng Pei-Suin
Published: March 2012

Don Marquis once wrote a poem about a fly who argued that he was ‘a vessel of righteousness scattering seeds of justice’ by helping to rid the world of alcoholics and the iniquitous who succumbed to the germs he carried to them. In justification stretched to absurdity, Marquis makes the point that grime, poverty and squalor do not constitute attractive subjects— surely it is easier to be enticed by bright lights and beauty, more tempting to revel in glitz, glamour and grandeur. Yet Pasolini’s Rome as depicted in his early films centers precisely on such wretchedness: set predominantly in the urban periphery, Pasolini’s camera determinedly avoids the more pleasant sights of the Pantheon or the Trevi Fountain, preferring instead the grimness of the borgate or the wilderness in the city outskirts. This essay focuses on Pasolini’s cinematic representation of the Roman slums, or the borgate, in Accattone by analysing on various levels its significance as a specific topographical space. My primary argument is that Pasolini’s alternate take on the borgate, replete with myth, utopian idealism and ideological ambition, nonetheless remains a flawed striving of romanticism,  whose redemption remains out of reach, and whose doom is inescapable.
Doris Salcedo: Shibboleth
Authors: Tse Annie
Published: March 2012

Doris Salcedo’s Shibboleth begins with an inconspicuous crack at the entrance of Tate Modern, inviting the viewer to follow its meandering course which runs 167 meters down the full length of the Turbine Hall. This encourages visitors to walk meditatively along the widening chasm, in contrast to a very different journey down Carsten Holler’s slides in a previous exhibition last year, also in the Turbine Hall, where all thought was suspended during the exhilarating descent. Shibboleth is groundbreaking – not only in the literal sense but also because it is the first time in Tate Modern’s history that a work of art has been embedded in the building itself, leaving a permanent mark after the crack is filled at the end of the exhibition in April.
Induced Pluripotent Stem Cells: a New Hope or a New Controversy?
Authors: Mukherjee Sayandip
Published: March 2012

It seems unbelievable but it is true – cells within an organism are genetically almost identical and yet they are as dissimilar structurally and functionally as the human mind can conceive. The neurons which conduct the nerve impulses, the villi which line the gastrointestinal tract, the retinal cells which are responsible for our vision, and the immune cells which act as the body’s sentinel have hardly anything in common between them. All these highly specialized cells are said to be terminally differentiated - they have lost their ability to become something else. Therefore, it was heralded as a significant breakthrough in science, when more than a decade ago, Ian Wilmut and colleagues at the Roslin Institute in Scotland demonstrated that a mature differentiated somatic cell taken from an adult mammal could be reprogrammed to give rise to an entire animal, which came to be known to the entire world as Dolly the sheep (Campbell 1996, 64).
London Festival of Architecture 2008: a Q&A with Peter Murray, Chairman of the Event
Authors: Szacka Léa-Catherine
Published: March 2012

This year, the biennial London Festival of Architecture (LFA) lasted a whole month. Indeed, from 20 June to 20 July 2008, the LFA put forward more than 600 activities across the capital, which together comprised the month-long celebration that tried to make architecture engaging and exciting for both a new and a familiar audience.
Joan Hoff, A Faustian Foreign Policy from Woodrow Wilson to George W. Bush: Dreams of Perfectability
Authors: Rietzler Katherine
Published: March 2012

Joan Hoff’s searing critique of American foreign policy from World War I to the War on Terror comes at a time when the Wilsonian legacy is attracting renewed interest. Different historians have chosen to emphasise different aspects of this legacy. Erez Manela has explored how antiimperialist intellectuals in Asia were empowered by the doctrine of self-determination during a global Wilsonian Moment, whereas David Kennedy has portrayed George W. Bush as Woodrow Wilson’s natural successor. Hoff, who has published widely on U.S. foreign relations and the American presidency, admits that a true characterisation of Wilsonian foreign policy is problematic. She resorts to a distinction between ‘good’ and ‘bad’ Wilsonianism: the former entails ‘spreading self-determination and free trade capitalism to the world through collective security arrangements’, while the latter indulges in unilateral interventionism. (10) In practice, this ambiguous inheritance has resulted in a unilateralist foreign policy tempered by occasional cooperation with other states.
Aaron Goodfellow, 'Pharmaceutical Intimacy: Sex, Death, and Methaphetamine'
Authors: Bennet Sophie
Published: March 2012

In 2008, Aaron Goodfellow challenged boundaries in sociology, anthropology and material culture studies with his article on sex, death and methamphetamine – an article which refuses to view drug (ab)use from a moral perspective. The result is a fascinating analysis of Mathew’s life. Mathew is a 24-year-old, white, HIV-positive crystal methamphetamine user, in a Baltimore rehabilitation institute on state parole, and receiving antiretroviral therapy (ART). In Mathew’s own words, he is ‘a public health threat number one, huh? (I’m) a gay crystal using, HIV positive convict’ (quoted in Goodfellow 2008, 280). Through his interactions with Mathew, Goodfellow explores the anthropological issue of the contingency of specific substances and of personhood within a modern, urban context, on the edge of ‘normative society’. The article supports the validity of Tilley’s work on objectification (2006); people and things (in this case, substances) are indivisible. The author encourages us to view Mathew’s situation not as an addiction, but as a partnership between Mathew and substances: Mathew often responds creatively to the substance’s agency with his own agency. In this review, I will briefly discuss the thought-provoking aspects of Goodfellow’s account, which will hopefully encourage you to read the article in full.
A New Species of the Genus Anatemnus (Pseudoscorpiones, Atemnidae) from China
Authors: Hu Jun-Fang , Zhang Feng
Published: March 2012

One new species belonging to Anatemnus Beier is reported from China under the name A. chaozhouensis sp. nov.
Do Surgical Interventions Influence Psychosexual and Cosmetic Outcomes in Women with Disorders of Sex Development?
Authors: Callens Nina , van der Zwan Yvonne G. , Drop Stenvert L. S. , Cools Martine , Beerendonk Catharina M. , Wolffenbuttel Katja P. , Dessens Arianne B.
Published: March 2012

Clinical practice developed to promote psychosexual well-being in DSD is under scrutiny. Although techniques for genital surgery have much improved lately, long-term studies on psychosexual functioning and cosmetic outcome on which to base treatment and counseling are scarce. We studied 91 women with a DSD. Feminizing surgery was performed in 64% of the women; in 60% of them, resurgery in puberty was needed after a single-stage procedure. Both patients and gynecologists were satisfied with the cosmetic appearance of the genitalia. However, forty percent of these females experienced sexuality-related distress and 66% was at risk for developing a sexual dysfunction, whether they had surgery or not. Recognizing the difficulty of accurate assessment, our data indicate that feminizing surgery does not seem to improve nor hamper psychosexual outcome, especially in patients with severe virilization.
Stability of Compressible Hollow Jet Pervaded by a Transverse Varying Magnetic Field
Authors: Elazab Samia S. , Rahman Samy A. , Hasan Alfaisal A. , Zidan Nehad A.
Published: March 2012

The magnetohydrodynamic stability of an ordinary compressible hollow cylinder pervaded by a transverse varying magnetic field, under the influence of capillary, inertia, and Lorentz force, has been developed. The problem is modelized. The basic equations formulated, solved, and, upon applying appropriate boundary conditions, the singular solutions are excluded. The eigenvalue relation has been derived and discussed. The capillary force has destabilizing influence only for long wavelengths in the axisymmetric perturbation but it is stabilizing in the rest and also so in the nonaxisymmetric perturbations. The compressibility increases the stable domains and simultaneously decreases those of instability. The electromagnetic force has different effects due to the axial uniform field and varying transverse one. The axial field is stabilizing for all wavelengths in all kinds of perturbations. The transverse field is stabilizing or not according to restrictions. Here, the high compressibility increases rapidly the magnetodynamic stable domains and leads to shrinking those of instability.
Recent Advances in Obesity: Genetics and Beyond
Authors: Cheung Wai W. , Mao Peizhong
Published: March 2012

The prevalence of obesity, which is a heritable trait that arises from the interactions of multiple genes and lifestyle factors, continues to increase worldwide, causing serious health problems and imposing a substantial economic burden on societies. For the past several years, various genetic epidemiological approaches have been utilized to identify genetic loci for obesity. Recent evidence suggests that development of obesity involves hormones and neurotransmitters (such as leptin, cocaine- and amphetamine-regulated transcript (CART), and ghrelin) that regulate appetite and energy expenditure. These hormones act on specific centers in the brain that regulate the sensations of satiety. Mutations in these hormones or their receptors can lead to obesity. Aberrant circadian rhythms and biochemical pathways in peripheral organs or tissues have also been implicated in the pathology of obesity. More interestingly, increasing evidence indicates a potential relation between obesity and central nervous system disorders (such as cognitive deficits). This paper discusses recent advances in the field of genetics of obesity with an emphasis on several established loci that influence obesity. These recently identified loci may hold the promise to substantially improve our insights into the pathophysiology of obesity and open up new therapeutic strategies to combat growing obesity epidemic facing the human population today.
Diversity and Habitat Use of Neotropical Harvestmen (Arachnida: Opiliones) in a Costa Rican Rainforest
Authors: Proud Daniel N. , Felgenhauer Bruce E. , Townsend Victor R. , Osula Daniel O. , Gilmore Wyman O. , Napier Zachery L. , Van Zandt Peter A.
Published: March 2012

In tropical rain forests, harvestmen assemblages are extremely diverse, with richness often exceeding 25 species. In the neotropics, there are published accounts of harvestmen faunas in South America rainforests (especially Amazonia), but relatively little is known about the community ecology of harvestmen in tropical forests of Central America. In this paper, we provide the first insights into the diverse assemblage of harvestmen inhabiting a wet forest at La Selva Biological Station, Costa Rica. Over five field seasons, we recorded 38 species. During our 2009 field season, we examined variation in species abundance, richness, and composition between adjacent successional forests (young secondary, mature secondary, and primary forests) as well as between distinct habitats (ground/litter layer and shrub/tree layer). Based on night samples (but not day), our results indicate that there are only minor differences in species composition and relative abundance between the forest ages, but no differences in richness. The ground/litter layer and shrub/tree layer habitats differed markedly in species composition, species richness, and relative abundance of several species. Our analysis of covariance supports the hypothesis that leg length is related to climbing behavior for several species belonging to Eupnoi and Laniatores.
A Set-Up of 7 Laser Triangulation Sensors and a Draw-Wire Sensor for Measuring Relative Displacement of a Piston Rod Mechanical Lead-Through Transmission in an Offshore Wave Energy Converter on the Ocean Floor
Authors: Strömstedt E. , Svensson O. , Leijon M.
Published: March 2012

A concept for offshore wave energy conversion is being developed at the Swedish Centre for Renewable Electric Energy Conversion at Uppsala University in Sweden. The wave energy converter (WEC) in focus contains a piston rod mechanical lead-through transmission for transmitting the absorbed mechanical wave energy through the generator capsule wall while preventing seawater from entering the capsule. A set-up of 7 laser triangulation sensors has been installed inside the WEC to measure relative displacement of the piston rod and its corresponding seal housing. A draw-wire sensor has also been set up to measure translator position and the axial displacement of the piston rod. The paper gives a brief introduction to the Lysekil research site, the WEC concept, and the direct drive of WEC prototype L2. A model of operation for the piston rod mechanical lead-through transmission is given. The paper presents sensor choice, configuration, adaptation, mounting, and measurement system calibration along with a description of the data acquisition system. Results from 60 s measurements of nominal operation two months apart with centered moving averages are presented. Uncertainty and error estimations with statistical analyses and signal-to-noise ratios are presented. Conclusions are drawn on the relative motions of the piston rod and the seal housing under normal operating conditions, and an assessment of the applicability of the measurement system is made.
Pearl diver: Identifying numbers on a number line
Authors: Trespalacios Jesús , Chamberline Barbara
Published: March 2012

An interactive online educational game presents opportunities to understand rational numbers contextualizing the sea bottom as a number line.
Donovan's computational strategies using the estimation calculator
Authors: Berry Robert Q.
Published: March 2012

A task-based interview is conducted with a fifth grader who is using an iPad application—a modified calculator that gives users visual feedback on their estimates for computational problems.
Selecting a Web Content Management System for an Academic Library Website
Authors: Black Elizabeth L.
Published: March 2012

This article describes the selection of a web content management system (CMS) at the Ohio State University Libraries. The author outlines the need for a CMS, describes the system requirements to support a large distributed content model and shares the CMS trial method used, which directly included content provider feedback side-by-side with the technical experts. The selected CMS is briefly described.
Oligodeoxynucleotide Containing S‐Functionalized 2′‐Deoxy‐6‐Thioguanosine: Facile Tools for Base‐Selective and Site‐Specific Internal Modification of RNA
Authors: Sasaki Shigeki , Onizuka Kazumitsu , Taniguchi Yosuke
Published: March 2012

Chemically modified oligonucleotides play a significant role for genomic research. Modified nucleosides, such as with a fluorescent dye, can be obtained by chemical synthesis. Site‐specifically modified long nucleic acids are obtained by ligation of chemically modified short oligonucleotides with enzyme, photochemistry, or catalytic DNA. The functionality‐transfer ODN (FT‐ODN), which contains 2′‐deoxy‐6‐thioguanosine (6‐thio‐dG) functionalized with the 2‐methyliden‐1,3‐diketone group, is hybridized with the target RNA to trigger the selective functionalization of the 4‐amino group of the cytosine base at pH 7 or the 2‐amino group of the guanine base at pH 9.4 or at pH 7.4 in the presence of NiCl2. In particular, the functionality‐transfer reaction (FTR) under the alkaline conditions or neutral conditions in the presence of NiCl2 proceeds rapidly and selectively to lead to the modification of the target guanine. The transfer reaction of the acetylene‐containing diketone group produces the acetylene‐modified RNA, which can be subjected to the Cu(I)‐catalyzed “click chemistry” with a variety of azide compounds for highly specific, internal modification of RNA. Curr. Protoc. Nucleic Acid Chem. 48:4.49.1‐4.49.16. © 2012 by John Wiley & Sons, Inc.
Synthesis of Dumbbell‐Shaped Cyclic RNAs for RNA Interference
Authors: Abe Naoko , Abe Hiroshi , Ito Yoshihiro
Published: March 2012

RNA interference (RNAi) is a potent and highly specific gene‐silencing phenomenon that was first reported for the nematode Caenorhabditis elegans. It has been discovered that genes could be silenced by introducing double‐stranded RNAs (dsRNAs) complementary to the messenger RNA sequences. Since then, RNAi has been shown as an evolutionarily well‐conserved process that plays an important role in host defense and in regulation of gene expression. Much effort has been dedicated to the application of the short dsRNA species (short interfering RNAs; siRNAs) as therapeutic agents, as they were shown to be effective in mammalian cells. Recently, we altered the structure of a siRNA molecule and produced dumbbell‐shaped nanocircular RNAs. RNA dumbbells were shown to be stabilized in serum compared with its siRNA counterpart, despite their natural RNA strand. It has also been found that RNA dumbbells containing a 23‐bp stem and two 9‐nt loops exhibit a prolonged RNAi effect in cultured mammalian cells. In this unit, we describe the synthesis of RNA dumbbells from the design, its enzymatic synthesis, and to the purification. Curr. Protoc. Nucleic Acid Chem. 48:16.4.1‐16.4.11. © 2012 by John Wiley & Sons, Inc.
Rheumatologists' quality of care for lupus: Comparison study between a university and county hospital
Authors: Dua Anisha B. , Aggarwal Rohit , Mikolaitis Rachel A. , Sequeira Winston , Block Joel A. , Jolly Meenakshi
Published: March 2012

Objective

Quality of care received from physicians may impact health outcomes in systemic lupus erythematosus (SLE). We compared physician quality of care (P‐QOC), health‐related quality of life (HRQOL), and disease activity and damage between SLE patients receiving outpatient care at a university and a county rheumatology clinic.

Methods

Forty‐two university and 41 county clinic SLE patients provided data on 5 P‐QOC parameters and HRQOL health outcomes (Short Form 36 [SF‐36] health survey and EuroQol 5‐domain instrument [EQ‐5D]). Disease activity and damage were measured. Chi‐square analysis and Student's t‐tests were used for comparisons.

Results

Overall satisfaction with medical care was similar; however, university patients had higher P‐QOC scores than county patients in “perception of doctor's understanding of impact of SLE on patient's life” (P = 0.02) and “providing education/educational information to understand their disease” (P = 0.05). HRQOL, disease activity, and damage were similar in the 2 groups. Overall satisfaction with medical care was directly related SF‐36 general health (r = 0.34, P = 0.03) and EQ‐5D visual analog scale on state of health (r = 0.39, P = 0.01), and inversely related EQ‐5D pain (r = −0.37, P = 0.02).

Conclusion

Patient perceptions of P‐QOC differed across the 2 centers despite similar demographics, clinical and HRQOL outcomes, and significant overlap in the physicians serving each clinic. Patients' overall satisfaction with medical care is associated with better HRQOL.
Association of slower walking speed with incident knee osteoarthritis–related outcomes
Authors: Purser Jama L. , Golightly Yvonne M. , Feng Qiushi , Helmick Charles G. , Renner Jordan B. , Jordan Joanne M.
Published: March 2012

Objective

To determine whether slower walking speed was associated with an increased risk of incident hip and knee osteoarthritis (OA)–related outcomes.

Methods

After providing informed consent, community‐dwelling participants in the Johnston County Osteoarthritis Project completed 2 home‐based interviews and an additional clinic visit for radiographic and physical evaluation. One thousand eight hundred fifty‐eight noninstitutionalized residents ages ≥45 years living for at least 1 year in 1 of 6 townships in Johnston County, North Carolina, completed the study's questionnaires and clinical examinations at baseline and at followup testing. Walking time was assessed using a manual stopwatch in 2 trials over an 8‐foot distance, and walking speed was calculated as the average of both trials. For the hip and knee, we examined 3 outcomes per joint site: radiographic OA (weight‐bearing anteroposterior knee radiographs, supine anteroposterior pelvic radiographs of the hip), chronic joint symptoms, and symptomatic OA. Covariates included age, sex, race, education, marital status, body mass index, number of self‐reported chronic conditions diagnosed by a health care provider, number of prescriptions, depressive symptoms, self‐rated health, number of lower body functional limitations, smoking, and physical activity.

Results

Faster walking speed was consistently associated with a lower incidence of radiographic (adjusted odds ratio [OR] 0.88, 95% confidence interval [95% CI] 0.79–0.97) and symptomatic knee OA (adjusted OR 0.84, 95% CI 0.75–0.95); slower walking speed was associated with a greater incidence of these outcomes across a broad range of different clinical and radiographic OA outcomes.

Conclusion

Slower walking speed may be a marker for incident knee OA, but other studies must confirm this finding.
Effects of the Molecular Weight and the Side‐Chain Length on the Photovoltaic Performance of Dithienosilole/Thienopyrrolodione Copolymers
Authors: Chu Ta‐Ya , Lu Jianping , Beaupré Serge , Zhang Yanguang , Pouliot Jean‐Rémi , Zhou Jiayun , Najari Ahmed , Leclerc Mario , Tao Ye
Published: March 2012

A series of low‐bandgap alternating copolymers of dithienosilole and thienopyrrolodione (PDTSTPDs) are prepared to investigate the effects of the polymer molecular weight and the alkyl chain length of the thienopyrrole‐4,6‐dione (TPD) unit on the photovoltaic performance. High‐molecular‐weight PDTSTPD leads to a higher hole mobility, lower device series resistance, a larger fill factor, and a higher photocurrent in PDTSTPD:[6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) bulk‐heterojunction solar cells. Different side‐chain lengths show a significant impact on the interchain packing between polymers and affect the blend film morphology due to different solubilities. A high power conversion efficiency of 7.5% is achieved for a solar cell with a 1.0 cm2 active area, along with a maximum external quantum efficiency (EQE) of 63% in the red region.
Routes to carboxylic acid functional acrylonitrile copolymers via N‐tert‐butyl‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl) free nitroxide based nitroxide‐mediated polymerization
Authors: Consolante Valerie , Maric Milan , Penlidis Alexander
Published: March 2012

Styrene (S)/acrylonitrile [AN; initial acrylonitrile molar feed compositions (fAN,0's) = 0.10–0.86) and tert‐butyl methacrylate (tBMA)/AN (fAN,0 = 0.10–0.80) copolymers were synthesized at 90°C in 50 wt % 1,4‐dioxane solutions with a unimolecular initiator, N‐(2‐methylpropyl)‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl)‐O‐(2‐carboxylprop‐2‐yl) hydroxylamine [BlocBuilder (BB)]. In the tBMA/AN copolymerizations, 8.0–8.5 mol % N‐tert‐butyl‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl) free nitroxide relative to BB was added. The S/AN copolymers exhibited narrow, monomodal molecular weight distributions (MWDs) with low polydispersities [weight‐average molecular weight (Mw)/number‐average molecular weight (Mn) = 1.14–1.26], and the Mn versus monomer conversion (X) plots were relatively linear (Mn = 18.1 kg/mol, X ≈ 0.7); this suggested that pseudo‐living behavior was approached. AN proved to be an effective controlling comonomer for tBMA because the tBMA/AN copolymers exhibited narrow monomodal MWDs with Mw/Mn = 1.17–1.50 and relatively linear Mn versus X plots to reasonably high X values (Mn = 15.6 kg/mol, X ≈ 0.6). The AN and S monomer reactivity ratios were rAN = 0.07 ± 0.01 and rS = 0.27 ± 0.02 (Fineman–Ross) and rAN = 0.10 ± 0.01 and rS = 0.28 ± 0.02 (Kelen–Tüdos), respectively; these values were in good agreement with conventional free‐radical polymerization. Error‐in‐variables model (EVM) analysis indicated that the use of cumulative composition S/AN data was more effective than typical approaches using low‐X data with the Mayo–Lewis model. The AN and tBMA reactivity ratios [rAN = 0.07 ± 0.01 and rtBMA = 1.24 ± 0.20 (Fineman–Ross) and rAN = 0.14 ± 0.01 and rtBMA = 0.89 ± 0.19 (Kelen–Tüdos)] were similar to those reported for related alkyl methacrylate/AN conventional radical copolymerizations. EVM analysis suggested significant experimental error was associated with the tBMA/AN system, and this warrants further investigation. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effects of predetermined nuclei and limited transformation on polymorphic crystallization in a model polymer
Authors: Misztal‐Faraj Beata , Ziabicki Andrzej
Published: March 2012

Formation of different polymorphic structures plays important role in crystallization of some polymers, like polypropylene, polycaproamide, poly(vinylidene difluoride), and others. Physical properties of such materials depend on phase structure, that is, fractions of different polymorphs. Basing on the model of many‐phase transitions (Ziabicki, J Chem Phys 2005, 123, 174103; Ziabicki and Misztal‐Faraj, J Mater Res, 2011, 26, 1585) a model system consisting of an amorphous phase, stable solid phase, and metastable polymorphic phase was analyzed. Two effects in the kinetics of polymorphic crystallization have been analyzed: effect of the presence of universal and/or selective predetermined nuclei and limited crystallizability resulting from molecular constraints in high‐molecular systems. Conditions in which different phase compositions (i.e., different proportions of individual phases) have been discussed. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
New constitutive modeling for time‐dependent mechanical behavior of polymers close to glass transition: Fundamentals and experimental validation
Authors: Billon Noëlle
Published: March 2012

The 1D limit of a 3D visco‐hyperelastic model is discussed and validated using a rich and rigorous database obtained on PMMA above Tg. Inelastic phenomena are accounted for as an evolution of internal variables assumed to be related to the alteration of microstructure that induces changes in well chosen constitutive parameters and dissipation of energy. Inelastic strain‐rate is deduced from energy balance between elastic and dissipative phenomenon. The concept allows introducing time effects in any rubber elasticity theory, resulting in a visco‐hyperelastic model consistent with continuum thermodynamics. In this article, Edwards‐Vilgis' model is used as the core and extended to a general time dependent constitutive model. Phenomenological models for disentanglement or crystallization are suggested that allow reproducing all viscoelastic effects using one unique model. An accounting for temperature and strain‐rate effects by an “a priori” uses of time temperature superposition principle is also proposed. The three concepts result in an original model of high efficiency. This new approach is a highly attractive way of modeling time dependent behavior of polymers over a wide range of temperature and strain‐rate up to large strains. This is demonstrated in the case of PMMA. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and properties of extruded thermoplastic starch/polymer blends
Authors: Huneault Michel A. , Li Hongbo
Published: March 2012

This article examines the starch gelatinization and the blend morphology development in blends of thermoplastic starch (TPS) with high‐density polyethylene, polypropylene, polystyrene, poly(lactic acid), and polycaprolactone. The TPS gelatinization and mixing with the second polymer was carried out on a twin‐screw extrusion process, where the starch was sequentially gelatinized, devolatilized, and then mixed in the molten state with a synthetic polymer. The role of excess water and process temperature on starch gelatinization was assessed by measuring the X‐ray scattering. All prepared blends included 25 % TPS that was dispersed in the synthetic polymer matrix. Compatibilized versions of these same blends were obtained by partially substituting the polymer matrices with maleated analogs. The blend morphology was probed by scanning electron microscopy. Complete starch gelatinization was obtained when the gelatinization process was carried out over 100°C regardless of amount of water used as co‐plasticizer. The blend morphologies were greatly improved when a maleated compatibilizer was added. Only TPS/PCL blends exhibited a finely dispersed TPS phase without the use of a compatibilizer. In general, the addition of the TPS reduced slightly the tensile modulus and strength of the different polymers and more importantly the elongation at break. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Micronization of polyethylene terephthalate via freezing of highly sheared emulsions of polyethylene terephthalate in saturated liquid tetrahydrofuran
Authors: Tapriyal D. , Fan X. , Heintz Y. , Morsi B. , Beckman E. , Enick R. , Sane A. , Thies M. , Schutte G. , Niederst J.
Published: March 2012

A novel technique for micronizing polyethylene terephthalate (PET) resin (∼ 3 mm) with saturated liquid tetrahydrofuran (THF) has been developed. PET pellets were introduced to a high‐pressure vessel filled halfway with THF at loadings up to ∼ 7 wt % PET. When the vessel was closed and heated, the PET pellets exhibited significant melting point depression at 190°C in saturated liquid THF at 17.1 bar. Although other organic solvents were also able to depress the melting point of PET, only THF was able to facilitate the formation of an emulsion of PET‐rich liquid droplets in the saturated liquid solvent when the mixture was agitated. In an attempt to generate the smallest possible PET droplets, a high‐speed (5000 rpm), close‐clearance, radial flow impeller was used to shear and disperse the droplets at ∼ 200°C and 20.1 bar. Emulsion was rapidly cooled while mixing. The PET droplets froze at ∼ 190°C, and the vessel was then cooled to ambient temperature. The excess liquid THF was decanted, and the PET particles were dried in a vacuum oven to remove residual THF. The PET particle sizes ranged between 2 and 70 μm, with number, area, and volume average diameters of 6, 20, and 30 μm, respectively. A comparison between the PET resin and PET powder properties indicated that the micronization reduced the Mw from 32,700 to 22,800. DSC results suggest that the rapid quench leads to a morphology different from equilibrium, with small somewhat imperfect crystallites, a lower overall degree of crystallinity, and a suppressed ΔCp at the glass transition. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and solution properties of an associative polymer with excellent salt‐thickening
Authors: Zhong Chuanrong , Wang Wei , Yang Mingming
Published: March 2012

To enhance apparent viscosities in brine solutions with high salinities for associative water‐soluble polymers, a novel macromonomer (APEO): allyl‐capped octylphenoxy poly(ethylene oxide) (degree of polymerization: 14) was synthesized, and a novel tetra‐polymer (PAVO) was synthesized by copolymerizing APEO, acrylamide (AM), sodium 2‐acrylamido‐2‐methylpropane sulfonate (NaAMPS), and vinyl biphenyl (VP). The macromonomer and the PAVO polymer were characterized with Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H‐NMR). The apparent viscosities of PAVO in pure water were very low over all polymer concentrations, and the critical association concentration (C*p) was 0.15 g dL−1. However, in brine solutions above 40 g L−1 NaCl or 10 g L−1 CaCl2, the intermolecular hydrophobic associations of octylphenyl groups and biphenyl groups were enhanced dramatically, the polymer chains were still comparatively extended due to the incorporation of APEO into the polymer, C*p was reduced to 0.10 g dL−1, and the apparent viscosities were significantly higher than in pure water. The PAVO brine solutions exhibited excellent salt‐thickening induced by metallic univalent or bivalent cations, heat‐thickening effect, shear‐thickening behavior, and thixotropy. Moreover, the brine solution also performed good resistance to ageing because of the simultaneous incorporation of bulky side groups. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Mechanical and rheological properties, and morphology of polyamide‐6/organoclay/elastomer nanocomposites
Authors: Isik‐Gulsac Isil , Yilmazer Ulku , Bayram Goknur
Published: March 2012

The effects of ethylene‐methyl acrylate‐glycidyl methacrylate (E‐MA‐GMA) terpolymer and three types of organoclays (Cloisite® 15A, 25A, and 30B) on mechanical and rheological properties, and morphology of impact modified polyamide‐6/montmorillonite ternary nanocomposites were investigated by X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), parallel disk rheometry, melt flow index measurements, and tensile and impact tests. The materials were prepared by melt blending using a co‐rotating twin‐screw extruder. XRD and TEM analyses showed that exfoliated‐intercalated nanocomposites were formed in both polyamide‐6/Cloisite® 25A and Cloisite® 30B binary nanocomposites and in ternary systems. SEM micrographs showed that rubber domain sizes were larger in the nanocomposites than in their corresponding polyamide‐6/elastomer blends. Generally, tensile strength, Young's modulus, and elongation at break decreased with the addition of elastomer to polyamide‐6/organoclay binary nanocomposites. In the melt state, liquid‐like behavior of polyamide‐6 slightly turned to pseudo solid‐like in the binary and ternary nanocomposites. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Intervertebral disc and macrophage interaction induces mechanical hyperalgesia and cytokine production in a herniated disc model in rats
Authors: Takada Toru , Nishida Kotaro , Maeno Koichiro , Kakutani Kenichiro , Yurube Takashi , Doita Minoru , Kurosaka Masahiro
Published: March 2012

Objective

The expression of proinflammatory factors such as tumor necrosis factor α (TNFα), interleukin‐6 (IL‐6), IL‐8, and prostaglandin E2 (PGE2) is significantly correlated with the symptoms of herniated disc disease. Among the different types of immune cells, macrophages are frequently noted in the herniated disc tissue. We undertook this study to clarify the interaction of the intervertebral disc (IVD) and macrophages with regard to the production of TNFα, IL‐6, IL‐8, and PGE2.

Methods

We developed 2 animal models to assess the interactions of IVDs with macrophages in terms of TNFα, IL‐6, IL‐8, and PGE2 production and pain‐related behavior. We also cocultured IVDs and macrophages to assess the role of TNFα in IL‐6, IL‐8, and PGE2 production.

Results

IVD autografts induced TNFα, IL‐6, IL‐8, and cyclooxygenase 2 (COX‐2) messenger RNA (mRNA) up‐regulation; macrophage infiltration was seen shortly after the autograft was implanted. A significant decrease was noted in the mechanical threshold of the ipsilateral paw following the up‐regulation of TNFα, IL‐6, IL‐8, and COX‐2 mRNA. Only IVD and macrophage cocultures resulted in IL‐8 and PGE2 up‐regulation. TNFα up‐regulation was maximized before that of IL‐6 and IL‐8. TNFα neutralization attenuated production of IL‐6 and PGE2, but not that of IL‐8. Neutralization of TNFα and IL‐8 significantly increased the paw withdrawal mechanical threshold in the IVD autograft and spinal nerve ligation model.

Conclusion

IVD–macrophage interaction plays a major role in sciatica and in the production of TNFα, IL‐6, IL‐8, and PGE2. TNFα is required for IL‐6 and PGE2 production, but not for IL‐8 production, during IVD–macrophage interaction. Neutralization of TNFα and IL‐8 can be a valuable therapy for herniated disc disease.
Multifunctional T cell reactivity with native and glycosylated type II collagen in rheumatoid arthritis
Authors: Snir Omri , Bäcklund Johan , Boström Julia , Andersson Ida , Kihlberg Jan , Buckner Jane H. , Klareskog Lars , Holmdahl Rikard , Malmström Vivianne
Published: March 2012

Objective

Type II collagen (CII) is a cartilage‐specific protein to which a loss of immune tolerance may trigger autoimmune reactions and cause arthritis. The major T cell epitope on CII, amino acids 259–273, can be presented by several HLA–DRB1*04 alleles in its native or posttranslational glycosylated form. The present study was undertaken to functionally explore and compare CII‐autoreactive T cells from blood and synovial fluid of patients with rheumatoid arthritis (RA).

Methods

Peripheral blood was obtained from HLA–DRB1*04–positive RA patients (n = 10) and control subjects (n = 10) and stimulated in vitro with several variants of the CII259–273 epitope, i.e., unmodified, glycosylated on Lys‐264, glycosylated on Lys‐270, or glycosylated on both Lys‐264 and Lys‐270. Up‐regulation of CD154 was used to identify responding T cells. These cells were further characterized by intracellular staining for interleukin‐17 (IL‐17), interferon‐γ (IFNγ), and IL‐2 by flow cytometry. Synovial T cells from RA patients were investigated in parallel.

Results

Multifunctional T cell responses toward all examined variants of the CII259–273 peptide could be detected in RA patients and, to a lesser extent, also in healthy HLA‐matched controls (P < 0.001). In RA patients, a comparison between blood‐ and joint‐derived T cell function revealed a significant increase in levels of the proinflammatory cytokine IFNγ in synovial T cells (P = 0.027). Studies of longitudinally obtained samples showed that T cell responses were sustained over the course of disease, and even included epitope spreading.

Conclusion

The identification of inflammatory T cell responses to both glycosylated and nonglycosylated variants of the major CII epitope in RA patients suggests that CII autoreactivity in RA may be more common than previously recognized.
Interleukin‐1 and tumor necrosis factor α blockade treatment of experimental polymyositis in mice
Authors: Sugihara Takahiko , Okiyama Naoko , Watanabe Naoto , Miyasaka Nobuyuki , Kohsaka Hitoshi
Published: March 2012

Objective

Histologic studies of the muscles suggest that cytokines are involved in inflammatory myopathy. The therapeutic effects of cytokine blockade are controversial, with anecdotal reports of clinical efficacy. The aim of this study was to discern the significance of interleukin‐1 (IL‐1) and tumor necrosis factor α (TNFα) as therapeutic targets in polymyositis (PM) by studying their involvement and the effects of their blockade in C protein–induced myositis (CIM), a murine model of PM.

Methods

C57BL/6 mice were immunized with recombinant skeletal C protein fragments to induce CIM. The expression of IL‐1 and TNFα in the muscles of mice with CIM was detected using immunohistochemical and real‐time polymerase chain reaction analyses. After the onset of myositis, the mice with CIM were treated with recombinant IL‐1 receptor antagonist (IL‐1Ra), anti–IL‐1R monoclonal antibody, recombinant TNF receptor (p75)–fusion protein (TNFR‐Fc), or anti‐TNFα monoclonal antibody. The muscles were examined histologically for the severity of myositis.

Results

IL‐1α– and TNFα‐positive macrophages were observed in the muscle tissue of mice with CIM as early as 7 days after immunization. IL‐1α, IL‐1β, and TNFα expression in the muscles increased as the severity of myositis peaked, at both the messenger RNA and protein levels. Continuous subcutaneous delivery of IL‐1Ra resulted in suppression of established CIM. Intermittent delivery (1‐day intervals) of anti–IL‐1R monoclonal antibody suppressed myositis, while intermittent delivery of IL‐1Ra did not suppress myositis. Treatment with anti‐TNFα monoclonal antibody and with TNFR‐Fc also reduced the severity of CIM.

Conclusion

IL‐1 and TNF blockade ameliorated CIM after disease onset and should potentially be a new strategy for the treatment of inflammatory myopathy. As IL‐1 blockade, treatment with anti–IL‐1R monoclonal antibody appeared more feasible than the other approaches.
Improved L‐lysine production with Corynebacterium glutamicum and systemic insight into citrate synthase flux and activity
Authors: van Ooyen Jan , Noack Stephan , Bott Michael , Reth Alexander , Eggeling Lothar
Published: March 2012

We here developed a series of Corynebacterium glutamicum strains with gradual decreased specific citrate synthase (CS) activity and quantified in a multifaceted approach the consequences of residual activity on the transcriptome, metabolome, and fluxome level as well as on L‐lysine formation and growth. We achieved an intended gradual L‐lysine yield increase and recognized and overcame further new limitations in the L‐lysine biosynthesis pathway to result in a strain with the highest yield reported so far when assayed under comparable conditions. As a non‐intended outcome, a detailed flux analysis revealed an almost constant flux through CS at 10% remaining CS activity, whereas the metabolome data revealed an increase in the oxaloacetate and acetyl‐CoA concentrations. Hence reduced CS activity is apparently efficiently buffered by increased concentrations of CS substrates, implying a certain robustness of the central metabolism in response of the imposed gene expressions. Biotechnol. Bioeng. 2012; 109:2070–2081. © 2012 Wiley Periodicals, Inc.
Female Juvenile Delinquency, Motherhood, and the Intergenerational Transmission of Aggression and Antisocial Behavior
Authors: Tzoumakis Stacy , Lussier Patrick , Corrado Raymond
Published: March 2012

The current study explored the intergenerational transmission of aggression and antisocial behavior by examining mothers' juvenile delinquency, their pregnancies, and its impact on their children's aggressive behavior. The sample consisted of the first 181 biological mothers recruited as part of the Vancouver Longitudinal Study on the Psychosocial Development of Children (British Columbia, Canada). Results indicated that mothers who were juvenile delinquents were more likely to experience social adversity, to use substances during pregnancy and to offend in adulthood. Furthermore, mothers who reported juvenile delinquency had children who were more physically aggressive and had an earlier onset of physical aggression. This pattern of association held when controlling for sociodemographics, social adversities, prenatal substance exposure, and criminal involvement in adulthood. The study findings highlighted the importance of understanding the role and impact of female delinquency and motherhood on the intergenerational transmission of antisocial behavior. Copyright © 2012 John Wiley & Sons, Ltd.
Xylose isomerase improves growth and ethanol production rates from biomass sugars for both Saccharomyces pastorianus and Saccharomyces cerevisiae
Authors: Miller Kristen P. , Gowtham Yogender Kumar , Henson J. Michael , Harcum Sarah W.
Published: March 2012

The demand for biofuel ethanol made from clean, renewable nonfood sources is growing. Cellulosic biomass, such as switch grass (Panicum virgatum L.), is an alternative feedstock for ethanol production; however, cellulosic feedstock hydrolysates contain high levels of xylose, which needs to be converted to ethanol to meet economic feasibility. In this study, the effects of xylose isomerase on cell growth and ethanol production from biomass sugars representative of switch grass were investigated using low cell density cultures. The lager yeast species Saccharomyces pastorianus was grown with immobilized xylose isomerase in the fermentation step to determine the impact of the glucose and xylose concentrations on the ethanol production rates. Ethanol production rates were improved due to xylose isomerase; however, the positive effect was not due solely to the conversion of xylose to xylulose. Xylose isomerase also has glucose isomerase activity, so to better understand the impact of the xylose isomerase on S. pastorianus, growth and ethanol production were examined in cultures provided fructose as the sole carbon. It was observed that growth and ethanol production rates were higher for the fructose cultures with xylose isomerase even in the absence of xylose. To determine whether the positive effects of xylose isomerase extended to other yeast species, a side‐by‐side comparison of S. pastorianus and Saccharomyces cerevisiae was conducted. These comparisons demonstrated that the xylose isomerase increased ethanol productivity for both the yeast species by increasing the glucose consumption rate. These results suggest that xylose isomerase can contribute to improved ethanol productivity, even without significant xylose conversion. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Discrete Bubble Model for Prediction of Bubble Behavior in 3D Fluidized Beds
Authors: Movahedirad S. , Ghafari M. , Dehkordi A. M.
Published: March 2012

A discrete bubble model has been developed taking into account multiple bubble‐bubble interactions and a delayed coalescence method. The obtained simulation results were compared with experimental data reported in literature. The simulation results predicted by the developed model indicate clearly that the multiple interactions of bubbles lead to more reasonable results than those predicted by a binary interaction model. In addition, two types of interaction models were applied and predicted results were compared. The frequency of gas bubbles passing through the bed cross section versus bed height follows the same trend as the experimental data.