bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of polyethylene‐grafted maleic anhydride as a compatibilizer on the morphology and tensile properties of (thermoplastic tapioca starch)/ (high‐density polyethylene)/(natural rubber) blends
Authors: Kahar A.W.M. , Ismail H. , Othman N. 
Published: February 2012

AbstractEffects of polyethylene‐grafted maleic anhydride as a compatibilizer on the tensile properties of (high‐density polyethylene)/(natural rubber)/(thermoplastic tapioca starch) (HDPE/NR/TPS) blends were investigated. The ratio of HDPE/NR was fixed at 70/30, and these materials were blended with TPS in concentrations varying from 5 to 30% by using a Haake Rheomix 600 mixer. Two series of HDPE/NR/TPS blends were prepared, i.e., with and without compatibilizer. Morphology and tensile properties of the HDPE/NR/TPS blends were evaluated as a function of TPS loading. The tensile strength and elongation at break decreased with the increase of TPS content. However, an improvement in the tensile strength was obtained for compatibilized blends as compared to uncompatibilized blends. The degrees of TPS adhesion and dispersion in HDPE/NR blends were revealed by scanning electron microscopy (SEM). Results showed that a smaller‐sized dispersed phase was achieved for compatibilized blends as compared to that for their uncompatibilized counterparts. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers
Rheometric study of the gelation and fusion processes of poly(vinyl chloride‐co‐vinyl acetate) plastisols with different commercial plasticizers
Authors: Zoller Agnes , Marcilla Antonio 
Published: February 2012

AbstractEvolution of the complex viscosity of pastes of PVC‐VA (vinyl chloride‐vinyl acetate copolymer) plasticized with different commercial plasticizers has been studied. Knowledge of the rheological behavior of the formulations allows for better understanding of the gelation and fusion processes. Twenty commercial plasticizers of different types and with different functional groups have been studied and are grouped into five families: phthalate esters with linear chains, phthalate esters with branched chains, adipates (normal and polymeric), citrates, and rest of the plasticizers (carboxylates, alkylsulfonates, and pentaerythritol ester derivatives). Interesting relationships among the observed rheologies and the nature and molecular weight of the plasticizer have been observed. The evolution of the complex viscosity with temperature—at the temperatures where the blowing agents normally used in PVC plastisol foaming processes generate the main amount of gas—has been newly discussed with regard to the chemical structure and molecular weight of all of the plasticizers used. It was found that several different dynamic processes must be synchronized in order to understand the relationships among the chemical structure, plasticization, plasticizer compatibility, rheological properties, and foaming process of such materials. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers
Thermal degradation and flame retardance of epoxy resins containing a microencapsulated flame retardant
Authors: Gao Ming , Wu Weihong , Wu Fachao 
Published: February 2012

AbstractTwo steps were used in the synthesis of a microencapsulated intumescent flame retardant (MIFR). First bis (1‐oxo‐2,6,7‐trioxa‐l‐phosphabicyclo[2.2.2]octane‐4‐methylol) phosphate melaminium salt (Melabis) was synthesized. Then the Melabis was encapsulated with melamine resin to obtain the MIFR. Its structure was characterized by XPS, SEM, and elemental analysis, and the factors affecting microencapsulation were identified and discussed. Epoxy resins (EP) were modified with the MIFR to prepare flame‐retardant EP, whose flammability and burning behavior were characterized by UL 94 and limiting oxygen index (LOI) tests. The microcapsules (20% by weight) were added to EP in order to achieve an LOI of 29.5% and a UL 94 rating of V‐0. The thermal properties of epoxy resins containing the MIFR were investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). The FR decreased by weight loss, Rmax (the maximum weight loss rate), and the thermal stability of EP while promoting the formation of an effective charring layer. The char structures were studied by SEM. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers
Clinicopathological Profile, Airway Management, and Outcome in Huge Multinodular Goiters: An Institutional Experience from an Endemic Goiter Region
Authors: Agarwal Amit , Agarwal Sudhi , Tewari Prabhat , Gupta Sushil , Chand Gyan , Mishra Anjali , Agarwal Gaurav , Verma A. K. , Mishra S. K. 
Published: February 2012

AbstractBackgroundHuge goiters are common in iodine‐deficient endemic regions. They are of concern to the surgeons because of the anticipated risk of difficult dissection and increased chances of surgical complications. Similarly, they are of concern to the anesthesiologists because of anticipated intubation‐related difficulties and post‐thyroidectomy tracheomalacia. In the present study we aimed to present our experience of managing goiters based on their gross weight, highlighting their clinicopathological profile, perioperative airway‐related difficulties, and management of surgical morbidity.MethodsRetrospective analysis of patients who underwent total thyroidectomy in the primary setting at our institute from 1995 to 2009 was carried out based on the gross gland weight. The patients were thus grouped into group A: ≤200 g; group B: 201 to ≤400 g; group C: 401 to ≤600 g; group D: >600 g.ResultsGroup A (660 cases); group B (108 cases); group C (36 cases); and group D (9 cases) were included. As the goiter size increased, the mean duration of goiter, compressive symptoms, retrosternal extension (RSE), airway deformity, intubation difficulty, and tracheomalacia increased. The rate of tracheostomy, sternotomy, hemorrhage, visceral injury, and hospital stay was high with huge goiters. These features were more marked in malignant goiters compared to benign goiters. However, the postoperative complications were comparable in both of those groups.ConclusionsLong‐standing huge goiters are common in iodine‐deficient endemic areas. The majority of patients have symptomatic or clinicoradiological evidence of airway involvement. The incidence of RSE, airway deformity, intubation difficulty, and tracheomalacia is high with huge goiters. The surgery is technically demanding with greater associated chances of injury to native structures. Malignancy influences the presentation and outcome in smaller goiters. In centers with experienced endocrine surgeons and dedicated anesthetists, huge goiters can be successfully managed with minimal short‐term and long‐term morbidity.
Improving test properties for neonatal cystic fibrosis screening in the Netherlands before the nationwide start by May 1st 2011
Authors: Cornel Martina C. , Gille Johan J. P. , Loeber J. Gerard , Langen Annette M. M. Vernooij‐van , Dankert‐Roelse Jeannette , Bolhuis Piet A. 
Published: February 2012

AbstractWhen new technical possibilities arise in health care, often attunement is needed between different actors from the perspectives of research, health care providers, patients, ethics and policy. For cystic fibrosis (CF) such a process of attunement in the Netherlands started in a committee of the Health Council on neonatal screening in 2005. In the balancing of pros and cons according to Wilson and Jungner criteria, the advantages for the CF patient were considered clear, even though CF remains a severe health problem with treatment. Nevertheless, screening was not started then, mainly since the specificity of the tests available at that time was considered too low. Many healthy infants would have been referred for sweat testing and much uncertainty would arise in their parents. Also the limited sensitivity for immigrants and the detection of less severe phenotypes and carriers were considered problematic. The Health Council recommended a pilot screening project which was subsequently performed in some provinces, leading to a 4‐step protocol: IRT, PAP, screening for a CFTR mutation panel, and sequencing of the CFTR gene. This would lead to the identification of 23 cases of classical CF, two infants with less severe forms and 12 carriers per year in the Netherlands. Thus many CF patients can be diagnosed early, while limiting the number of referrals, the number of infants with less severe forms diagnosed and the number of carriers identified. Technical solutions were found to limit the ethical problems. A nationwide program using this four step protocol started by 1 May 2011.
Genetic Counseling as a Tool for Type 2 Diabetes Prevention: A Genetic Counseling Framework for Common Polygenetic Disorders
Authors: Waxler Jessica L. , O'Brien Kelsey E. , Delahanty Linda M. , Meigs James B. , Florez Jose C. , Park Elyse R. , Pober Barbara R. , Grant Richard W. 
Published: February 2012

AbstractAdvances in genetic epidemiology have increased understanding of common, polygenic preventable diseases such as type 2 diabetes. As genetic risk testing based on this knowledge moves into clinical practice, we propose that genetic counselors will need to expand their roles and adapt traditional counseling techniques for this new patient set. In this paper, we present a genetic counseling intervention developed for a clinical trial [Genetic Counseling/Lifestyle Change for Diabetes Prevention, ClinicalTrials.gov identifier: NCT01034319] designed to motivate behavioral changes for diabetes prevention. Seventy‐two phenotypically high‐risk participants received counseling that included their diabetes genetic risk score, general education about diabetes risk factors, and encouragement to participate in a diabetes prevention program. Using two validated genetic counseling scales, participants reported favorable perceived control and satisfaction with the counseling session. Our intervention represents one model for applying traditional genetic counseling principles to risk testing for polygenetic, preventable diseases, such as type 2 diabetes.
Sinking, merging and stationary plumes in a coupled chemotaxis-fluid model: a high-resolution numerical approach
Authors: Chertock A. , Fellner K. , Kurganov A. , Lorz A. , Markowich P. A. 
Published: February 2012

AbstractAquatic bacteria like Bacillus subtilis are heavier than water yet they are able to swim up an oxygen gradient and concentrate in a layer below the water surface, which will undergo Rayleigh–Taylor-type instabilities for sufficiently high concentrations. In the literature, a simplified chemotaxis–fluid system has been proposed as a model for bio-convection in modestly diluted cell suspensions. It couples a convective chemotaxis system for the oxygen-consuming and oxytactic bacteria with the incompressible Navier–Stokes equations subject to a gravitational force proportional to the relative surplus of the cell density compared to the water density. In this paper, we derive a high-resolution vorticity-based hybrid finite-volume finite-difference scheme, which allows us to investigate the nonlinear dynamics of a two-dimensional chemotaxis–fluid system with boundary conditions matching an experiment of Hillesdon et al. (Bull. Math. Biol., vol. 57, 1995, pp. 299–344). We present selected numerical examples, which illustrate (i) the formation of sinking plumes, (ii) the possible merging of neighbouring plumes and (iii) the convergence towards numerically stable stationary plumes. The examples with stable stationary plumes show how the surface-directed oxytaxis continuously feeds cells into a high-concentration layer near the surface, from where the fluid flow (recurring upwards in the space between the plumes) transports the cells into the plumes, where then gravity makes the cells sink and constitutes the driving force in maintaining the fluid convection and, thus, in shaping the plumes into (numerically) stable stationary states. Our numerical method is fully capable of solving the coupled chemotaxis–fluid system and enabling a full exploration of its dynamics, which cannot be done in a linearised framework.
Dissipation element analysis in turbulent channel flow
Authors: Aldudak Fettah , Oberlack Martin 
Published: February 2012

AbstractIn order to analyse the geometric structure of turbulent flow patterns and their statistics for various scalar fields we adopt the dissipation element (DE) approach and apply it to turbulent channel flow by employing direct numerical simulations (DNS) of the Navier–Stokes equations. Gradient trajectories starting from any point in a scalar field $\phi (x, y, z, t)$ in the directions of ascending and descending scalar gradients will always reach an extremum, i.e. a minimum or a maximum point, where $\boldsymbol{\nabla} \phi = 0$. The set of all points and trajectories belonging to the same pair of extremal points defines a dissipation element. Extending previous DE approaches, which were only applied to homogeneous turbulence, we here focus on exploring the influence of solid walls on the dissipation element distribution. Employing group-theoretical methods and known symmetries of Navier–Stokes equations, we observe for the core region of the flow, i.e. the region beyond the buffer layer, that the probability distribution function (p.d.f.) of the DE length exhibits an invariant functional form, in other words, self-similar behaviour with respect to the wall distance. This is further augmented by the scaling behaviour of the mean DE length scale which shows a linear scaling with the wall distance. The known proportionality of the mean DE length and the Taylor length scale is also revisited. Utilizing a geometric analogy we give the number of DE elements as a function of the wall distance. Further, it is observed that the DE p.d.f. is rather insensitive, i.e. invariant with respect both to the Reynolds number and the actual scalar $\phi $ which has been employed for the analysis. In fact, a very remarkable degree of isotropy is observed for the DE p.d.f. in regions of high shear. This is in stark contrast to classical Kolmogorov scaling laws which usually exhibit a strong dependence on quantities such as shear, anisotropy and Reynolds number. In addition, Kolmogorov’s scaling behaviour is in many cases only visible for very large Reynolds numbers. This is rather different in the present DE approach which applies also for low Reynolds numbers. Moreover, we show that the DE p.d.f. agrees very well with the log-normal distribution and derive a log-normal p.d.f. model taking into account the wall-normal dependence. Finally, the conditional mean scalar differences of the turbulent kinetic energy at the extremal points of DE are examined. We present a power law with scaling exponent of $2/ 3$ known from Kolmogorov’s hypothesis for the centre of the channel and a logarithmic law near the wall.
Maintenance of low sodium and high potassium levels in cells and in tendon/collagen
Authors: Cameron Ivan L. , Lanctot Anthony C. , Fullerton Gary D. 
Published: February 2012

AbstractMammalian cells have a higher concentration of potassium and a lower concentration of sodium than their extracellular environment. The mechanisms responsible for the unequal distribution of these ions are commonly ascribed to the presence of an energy requiring plasma membrane ATPase pump, and the presence of membrane channels that pass one ion selectively, while excluding others. This report deals with other mechanisms that might explain this heterogeneous distribution of ions. To study other mechanisms, we turned to a non‐living system, specifically tendon/collagen to eliminate the contribution of the membrane pump and channels. A simple gravimetric method was designed to measure solute accumulation or exclusion during rehydration of a well‐washed, carefully dried and well‐characterized protein specimen (tendon/collagen). Exposure to physiological salt concentrations resulted in selective exclusion of Na+ over K+, whereas exposure to low‐salt concentration resulted in accumulation of these solutes. It is postulated that this solute redistribution occurs in all hydrated proteins and is partially responsible for the heterogeneous solute distribution in cells presently assigned to pump and channel mechanisms. Physical and thermodynamic mechanisms are offered to explain the observed heterogeneous solute distributions.
Vocal Fold Phase Asymmetries in Patients With Voice Disorders: A Study Across Visualization Techniques
Authors: Bonilha Heather Shaw , Deliyski Dimitar D. , Whiteside Joanna Piasecki , Gerlach Terri Treman 
Published: February 2012

Purpose
To examine differences in vocal fold vibratory phase asymmetry judged from stroboscopy, high-speed videoendoscopy (HSV), and the HSV-derived playbacks of mucosal wave kymography, digital kymography, and a static medial digital kymography image of persons with hypofunctional and hyperfunctional voice disorders. Differences between the methods of visual judgments and objective measures of left-right phase asymmetry were assessed. The findings were compared with those from a previous study with vocally normal speakers.

Method
Forty-nine persons with voice disorders underwent stroboscopy and HSV. The HSV images were processed, resulting in 4 different spatial or kymographic displays. Two types of phase asymmetries, left-right and anterior-posterior, were visually rated. Objective measures of left-right phase asymmetry were obtained.

Results
From stroboscopy, the HSV playback, and the HSV-derived playbacks, left-right phase symmetry was judged to be symmetrical in 41%, 32%, and 19% of cases, respectively. This difference in playbacks was not seen for anterior-posterior asymmetry. Correlation between visual judgments and objective measures was mild for stroboscopy and moderate to high for all HSV-based playbacks.

Conclusions
The use of kymography appears important for judgments of phase asymmetry. Stroboscopy appears to be sensitive, but possibly not specific, to phase asymmetries. Further development of objective measures is warranted for this feature.
High-resolution structure of a BRICHOS domain and its implications for anti-amyloid chaperone activity on lung surfactant protein C
Authors: Willander Hanna , Askarieh Glareh , Landreh Michael , Westermark Per , Nordling Kerstin , Keränen Henrik , Hermansson Erik , Hamvas Aaron , Nogee Lawrence M. , Bergman Tomas , Saenz Alejandra , Casals Cristina , Åqvist Johan , Jörnvall Hans , Berglund Helena , Presto Jenny , Knight Stefan D. , Johansson Jan 
Published: February 2012

BRICHOS domains are encoded in > 30 human genes, which are associated with cancer, neurodegeneration, and interstitial lung disease (ILD). The BRICHOS domain from lung surfactant protein C proprotein (proSP-C) is required for membrane insertion of SP-C and has anti-amyloid activity in vitro. Here, we report the 2.1 Å crystal structure of the human proSP-C BRICHOS domain, which, together with molecular dynamics simulations and hydrogen-deuterium exchange mass spectrometry, reveals how BRICHOS domains may mediate chaperone activity. Observation of amyloid deposits composed of mature SP-C in lung tissue samples from ILD patients with mutations in the BRICHOS domain or in its peptide-binding linker region supports the in vivo relevance of the proposed mechanism. The results indicate that ILD mutations interfering with proSP-C BRICHOS activity cause amyloid disease secondary to intramolecular chaperone malfunction.
Subunit order of eukaryotic TRiC/CCT chaperonin by cross-linking, mass spectrometry, and combinatorial homology modeling
Authors: Kalisman Nir , Adams Christopher M. , Levitt Michael 
Published: February 2012

The TRiC/CCT chaperonin is a 1-MDa hetero-oligomer of 16 subunits that assists the folding of proteins in eukaryotes. Low-resolution structural studies confirmed the TRiC particle to be composed of two stacked octameric rings enclosing a folding cavity. The exact arrangement of the different proteins in the rings underlies the functionality of TRiC and is likely to be conserved across all eukaryotes. Yet despite its importance it has not been determined conclusively, mainly because the different subunits appear nearly identical under low resolution. This work successfully addresses the arrangement problem by the emerging technique of cross-linking, mass spectrometry, and modeling. We cross-linked TRiC under native conditions with a cross-linker that is primarily reactive toward exposed lysine side chains that are spatially close in the context of the particle. Following digestion and mass spectrometry we were able to identify over 60 lysine pairs that underwent cross-linking, thus providing distance restraints between specific residues in the complex. Independently of the cross-link set, we constructed 40,320 (= 8 factorial) computational models of the TRiC particle, which exhaustively enumerate all the possible arrangements of the different subunits. When we assessed the compatibility of each model with the cross-link set, we discovered that one specific model is significantly more compatible than any other model. Furthermore, bootstrapping analysis confirmed that this model is 10 times more likely to result from this cross-link set than the next best-fitting model. Our subunit arrangement is very different than any of the previously reported models and changes the context of existing and future findings on TRiC.
Soluble ST2 is associated with adverse outcome in patients with heart failure of ischaemic aetiology
Authors: Broch Kaspar , Ueland Thor , Nymo Ståle H. , Kjekshus John , Hulthe Johannes , Muntendam Pieter , McMurray John J. , Wikstrand John , Cleland John G. , Aukrust Pål , Gullestad Lars ,   on behalf of the CORONA Study Group
Published: February 2012

AimsIn patients with ischaemic heart failure (HF), myocardial dysfunction often progresses. Elevated levels of soluble ST2 (sST2) are associated with a poor prognosis, but an association between sST2 and worsening heart failure per se has not been established. We assessed the association between sST2 and cause‐specific outcome in 1449 patients enrolled in the Controlled Rosuvastatin Multinational Trial in Heart Failure (CORONA study).Methods and resultsSoluble ST2 was measured with a highly sensitive immunoassay in 1449 patients ≥60 years of age with left ventricular ejection fraction (LVEF) ≤40% due to ischaemic heart disease. By Cox regression analyses, we found sST2 to be associated with the primary endpoint, i.e. a composite of cadiovascular (CV) death, non‐fatal myocardial infarction, or stroke, as well as all pre‐defined secondary endpoints in the CORONA study, even after adjustment for baseline clinical variables. After adjustment for N‐terminal pro brain natriuretic peptide and C‐reactive protein, the association between sST2 and the primary endpoint was attenuated and no longer statistically significant. However, sST2 remained associated with death due to worsening HF, hospitalization due to worsening HF, and hospitalization due to any CV cause, even after full adjustment.ConclusionsSoluble ST2 is associated with adverse outcomes in older patients with systolic, ischaemic HF. In particular, sST2 is independently associated with worsening HF.