bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical yield of diagnostic endoscopic retrograde cholangiopancreatography in orthotopic liver transplant recipients With suspected biliary complications
Authors: Elmunzer Joseph B. , DeBenedet Anthony T. , Volk Michael L. , Sonnenday Christopher J. , Waljee Akbar K. , Fontana Robert J. , Oza Aarti B. , Singal Amit , Englesbe Michael J. , Scheiman James M.
Published: August 2012

Diagnostic endoscopic retrograde cholangiopancreatography (D-ERCP) is commonly performed for the evaluation of biliary complications after orthotopic liver transplantation (OLT). This practice is contrary to the national trend of reserving endoscopic retrograde cholangiopancreatography (ERCP) for therapeutic purposes. Our aim was to evaluate the clinical yield and complications of D-ERCP in OLT recipients. In this retrospective study, 165 OLT recipients who underwent ERCP between January 2006 and December 2010 at the University of Michigan were divided into 2 groups: (1) a therapeutic endoscopic retrograde cholangiopancreatography (T-ERCP) group (if they met prespecified criteria that suggested a high likelihood of endoscopic intervention) and (2) a D-ERCP group (if there was clinical suspicion of biliary disease but they did not meet any criteria). The 2 groups were compared with respect to the proportion of subjects undergoing high-yield ERCP, which was defined as a procedure resulting in a clinically important intervention that modified the disease course. 66.3% of the D-ERCP procedures were classified as high-yield, whereas 90.1% of the T-ERCP procedures were (P < 0.001). Serious complications were infrequent in both groups. A survey of practitioners caring for OLT recipients suggested that the rate of high-yield D-ERCP seen in this study is congruent with what is considered acceptable in clinical practice. In conclusion, although T-ERCP is more likely to reveal a pathological process requiring an intervention, D-ERCP appears to be an acceptable clinical strategy for OLT recipients because of the high likelihood of a high-yield study and the low rate of serious complications. Liver Transpl, 2012. © 2012 AASLD.
Memory and Development of Textures of Polydomain Nematic Elastomers
Authors: Higaki Haruko , Urayama Kenji , Takigawa Toshikazu
Published: August 2012

The texture development during the polydomain‐to‐monodomain (PM) transition in nematic elastomers with isotropic (I‐PNE) or nematic genesis (N‐PNE) is studied. I‐PNE exhibits a uniform polydomain texture, and the PM transition occurs at a constant small force, resulting in a uniform monodomain texture. N‐PNE exhibits the Schlieren texture that is composed of large domains with many defects and is similar to that before cross‐linking. N‐PNE requires much more mechanical work than I‐PNE for the PM transition. In N‐PNE, remnants of the initial texture are still observed in the stretched aligned state, while the initial texture and dimensions are completely restored when the imposed strain is removed. The permanent memory of the initial texture becomes a robust constraint to the rotation of the local directors.
One‐Pot Preparation of Core–Shell, Organic–Inorganic, Hybrid Latexes by In Situ Nanoparticle Precipitation in Pickering Emulsion Polymerization
Authors: Pakdel Amirsaeid , Pourmahdian Saeed , Eslami Hormoz
Published: August 2012

A one‐pot emulsion polymerization process to produce silica nanoparticles fixed on polymer particles is presented. Simultaneous nanoparticle formation/monomer emulsification and later polymerization of monomers prevent the agglomeration of silica particles and result in hybrid organic–inorganic, core–shell latexes. The emulsion polymerization of methyl methacrylate is performed using nascent silica nanoparticles, cetyltrimethylammonium bromide, and ammonium persulfate as Pickering surfactant, cosurfactant, and initiator, respectively. The effects of parameters like temperature, initiator type and concentration, and cosurfactant and silica precursor amounts on the polymerization, coagulation percentage, and morphology of hybrid particles are determined using SEM and TEM.
Thermoresponsive Supramolecular Dendrimers via Host–Guest Interactions
Authors: Yan Jiatao , Zhang Xiaoqian , Zhang Xiuqiang , Liu Kun , Li Wen , Wu Peiyi , Zhang Afang
Published: August 2012

A series of first‐ and second‐generation supramolecular dendrimers (SDs) was prepared via host–guest interaction from the cyclodextrin trimer and oligoethylene glycol (OEG)‐based threefold dendritic guests. These SDs are water soluble at room temperature but show characteristic thermoresponsive behavior at elevated temperatures. Their thermoresponsiveness was investigated by UV–Vis spectroscopy and dynamic light scattering measurements. Supramolecular complexation from a mixture of two dendritic guests with different hydrophilicity was performed to check the feasibility to tune the phase transition temperatures of codendrimers. Based on temperature‐varied 1H NMR spectra, it was found that the SDs start to decompose when the OEG units are dehydrated.
Synthesis and Characterization of β‐CD‐Coated Polystyrene Microspheres by γ‐Ray Radiation Emulsion Polymerization
Authors: Xu Dezhi , Wang Mozhen , Ge Xuewu , Lam Michael Hon‐Wah
Published: August 2012

Polystyrene (PS) microspheres coated with β‐cyclodextrin (β‐CD) were fabricated via γ‐ray‐induced emulsion polymerization in a ternary system of styrene/β‐CD/water (St/β‐CD/water). The solid inclusion complex of St and β‐CD particles formed at the St droplets–water interface can stabilize the emulsion as the surfactant. TEM and XPS results showed that β‐CD remains on the surface of PS particles. The average size of the PS particles increases from 186 to 294 nm as the weight ratio of β‐CD to St rises from 5% to 12.5%. The water contact angle (CA) of PS latex film is lower than 90°, and reduces with the β‐CD content even to 36°. Thus, this work provides a new and one‐pot strategy to surface hydrophilic modification on hydrophobic polymer particles with cyclodextrins through radiation emulsion polymerization.
Prospective optical motion correction for 3D time‐of‐flight angiography
Authors: Kopeinigg Daniel , Aksoy Murat , Forman Christoph , Straka Matus , Seaman Danielle , Rosenberg Jarrett , Fleischmann Dominik , Hornegger Joachim , Bammer Roland
Published: August 2012

Magnetic resonance angiograms are often nondiagnostic due to patient motion. In clinical practice, the available time to repeat motion‐corrupted scans is very limited—especially in patients who suffer from acute cerebrovascular conditions. Here, the feasibility of an optical motion correction system to prospectively correct patient motion for 3D time‐of‐flight magnetic resonance angiography was investigated. Experiments were performed on five subjects with and without parallel imaging (SENSE R = 2) on a 1.5 T unit. Two human readers assessed the data and were in good agreement (kappa: 0.77). The results from this study indicate that the optical motion correction system greatly reduces motion artifacts when motion was present and did not impair the image quality in the absence of motion. Statistical analysis showed no significant difference between the (vendor‐provided) SENSE and the nonaccelerated acquisitions. In conclusion, the optical motion correction system tested in this study has the potential to greatly improve 3D time‐of‐flight angiograms regardless of whether it is used with or without SENSE. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
MRI‐related static magnetic stray fields and postural body sway: A double‐blind randomized crossover study
Authors: van Nierop Lotte E. , Slottje Pauline , Kingma Herman , Kromhout Hans
Published: August 2012

We assessed postural body sway performance after exposure to movement induced time‐varying magnetic fields in the static magnetic stray field in front of a 7 Tesla (T) magnetic resonance imaging scanner. Using a double blind randomized crossover design, 30 healthy volunteers performed two balance tasks (i.e., standing with eyes closed and feet in parallel and then in tandem position) after standardized head movements in a sham, low exposure (on average 0.24 T static magnetic stray field and 0.49 T·s−1 time‐varying magnetic field) and high exposure condition (0.37 T and 0.70 T·s−1). Personal exposure to static magnetic stray fields and time‐varying magnetic fields was measured with a personal dosimeter. Postural body sway was expressed in sway path, area, and velocity. Mixed‐effects model regression analysis showed that postural body sway in the parallel task was negatively affected (P < 0.05) by exposure on all three measures. The tandem task revealed the same trend, but did not reach statistical significance. Further studies are needed to investigate the possibility of independent or synergetic effects of static magnetic stray field and time‐varying magnetic field exposure. In addition, practical safety implications of these findings, e.g., for surgeons and others working near magnetic resonance imaging scanners need to be investigated. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Catalytic multiecho phase unwrapping scheme (CAMPUS) in multiecho gradient echo imaging: Removing phase wraps on a voxel‐by‐voxel basis
Authors: Feng Wei , Neelavalli Jaladhar , Haacke E. Mark
Published: August 2012

Phase images reflect local field variations including susceptibility contributions and play a key role in a number of imaging applications. However, due to the limited dynamic range of phase values, phase wrapping invariably occurs at long echo times. High pass filtering and region‐growing approaches have been common themes in the effort of removing phase wraps. In this article, a novel voxel‐by‐voxel phase unwrapping scheme taking advantage of short interecho spacing of multiecho gradient echo imaging is proposed. By removing spurious sources of phase variations and exploiting the special features of the flow‐induced phase component, phase increments during adjacent echoes can be unveiled that exhibit no phase aliasing. This unaliased phase information is then used to unwrap all the phase images at all of the echoes. Data of 15 volunteers scanned at 3 and 1.5T were processed with the proposed algorithm and two other algorithms in the literature (PhUN and branch cut). It is shown that the proposed approach is fast and effective in unwrapping all the phase values even for voxels in the eyes and the skull, which the other algorithms failed to unwrap. Thus, in multiecho gradient echo imaging, the proposed algorithm has major potential in various applications involving phase processing. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Commissioning of MRI‐only based treatment planning procedure for external beam radiotherapy of prostate
Authors: Kapanen Mika , Collan Juhani , Beule Annette , Seppälä Tiina , Saarilahti Kauko , Tenhunen Mikko
Published: August 2012

In radiotherapy, target tissues are defined best on MR images due to their superior soft tissue contrast. Computed tomography imaging is geometrically accurate and it is needed for dose calculation and generation of reference images for treatment localization. Co‐registration errors between MR and computed tomography images can be eliminated using magnetic resonance imaging‐only based treatment planning. Use of ionizing radiation can be avoided which is especially important in adaptive treatments requiring several re‐scans. We commissioned magnetic resonance imaging‐only based procedure for external radiotherapy, treatment planning of the prostate cancer. Geometrical issues relevant in radiotherapy, were investigated including quality assurance testing of the scanner, evaluation of the displacement of skin contour and radiosensitive rectum wall, and detection of intraprostatic fiducial gold seed markers used for treatment localization. Quantitative analysis was carried out for 30 randomly chosen patients. Systematic geometrical errors were within 2.2 mm. The gold seed markers were correctly identified for 29 out of the 30 patients. Positions of the seed midpoints were consistent within 1.3 mm in magnetic resonance imaging and computed tomography. Positional error of rectal anterior wall due to susceptibility effect was minimal. Geometrical accuracy of the investigated equipment and procedure was sufficient for magnetic resonance imaging‐only based radiotherapy, treatment planning of the prostate cancer including treatment virtual simulation. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
A case of peripheral nerve microvasculitis associated with multiple myeloma and bortezomib treatment
Authors: Mauermann Michelle L. , Blumenreich Martin S. , Dispenzieri Angela , Staff Nathan P.
Published: August 2012

Introduction: Bortezomib‐induced peripheral neuropathy typically presents as a painful, length‐dependent sensory predominant neuropathy. Methods: A case report, including nerve pathology, is presented of a man with multiple myeloma who developed a severe motor predominant polyradiculoneuropathy in the setting of bortezomib treatment. We also review the Mayo Clinic Hematology Dysproteinemia database for patients treated with bortezomib. Results: A 53‐year‐old man with Stage III multiple myeloma developed a severe motor predominant polyradiculoneuropathy following bortezomib treatment with electrophysiological features of multiple conduction blocks and pathological evidence of peripheral nerve microvasculitis. Our institutional experience is that 36.5% of dysproteinemia patients treated with bortezomib develop treatment‐emergent peripheral neuropathy, and the most common pattern is a painful sensory predominant peripheral neuropathy. Conclusions: A motor predominant polyradiculoneuropathy is a rare presentation of bortezomib‐associated peripheral neuropathy in multiple myeloma patients which may progress despite treatment withdrawal and may be due to microvasculitis. Muscle Nerve, 2012
Clinical evolution of pure upper motor neuron disease/dysfunction (PUMMD)
Authors: D'amico Emanuele , Pasmantier Meredith , Lee Yei‐won , Weimer Louis , Mitsumoto Hiroshi
Published: August 2012

Introduction: PLS is defined as pure upper motor neuron disease/dysfunction (PUMND) beyond 48 months after symptom onset. We know little about its early stages, but such knowledge would help to identify the mechanisms underlying PLS and ALS and determine why PLS patients seem to be protected against lower MND (LMND). Methods: We reviewed 622 MND cases during a 4‐year period and identified 34 patients with PUMND (5.4%). Results: Among 23 cases with follow‐up data/electromyograms (EMGs; 2 had only 1 EMG), 13 (57%) remained classified as PUMND, and 8 (35%) developed LMND (mean, 51.4 months after onset). Of these 8, LMND developed in 3 after 48 months from symptom onset. Patients with PUMND and LMND were more functionally impaired (P = 0.02). Separately, we identified 5 patients with PUMND who developed LMND long after 48 months (range, 50–127 months). Conclusions: PLS belongs to the ALS spectrum, and perhaps all cases eventually develop LMND. Muscle Nerve, 2013
Camptocormia as a late presentation in a manifesting carrier of duchenne muscular dystrophy
Authors: Findlay Andrew R. , Lewis Sarah , Sahenk Zarife , Flanigan Kevin M.
Published: August 2012

Introduction:

Camptocormia, or bent spine syndrome, is an abnormal posture consisting of forward flexion of the spine that disappears when a patient is supine. It is associated with a wide variety of myopathic disorders that affect paraspinal muscles, including inflammatory and inherited myopathies.

Methods:

We describe a woman who presented with camptocormia in her eighth decade.

Results:

Skeletal muscle biopsy showed mild nonspecific changes, but her family history was significant for a son who died of Duchenne muscular dystrophy (DMD). Genetic analysis of DMD confirmed that she was a heterozygous carrier of a mutation.

Conclusions:

In the absence of any alternate explanation, we interpret her symptoms to be a manifestation of her DMD carrier state. To our knowledge, this represents the first reported example of camptocormia as the presenting symptom in a carrier and suggests that a manifesting carrier state should be considered in the differential diagnosis for women with unexplained camptocormia. Muscle Nerve, 2013
Novel mutations in the gene encoding very long‐chain acyl‐CoA dehydrogenase identified in patients with partial carnitine palmitoyltransferase ii deficiency
Authors: Isackson Paul J. , Sutton Kristin A. , Hostetler Karl Y. , Vladutiu Georgirene D.
Published: August 2012

Introduction: Twenty‐six patients with clinical symptoms of adult onset carnitine palmitoyltransferase II (CPTII) deficiency were examined. All patients had skeletal muscle CPTII enzyme activity levels indicative of heterozygosity for CPT2 mutations, however sequence analysis identified no pathogenic mutations within the CPT2 gene. Methods: Because the reaction product of CPTII is the substrate for very long‐chain acyl‐CoA dehydrogenase (VLCAD), we examined the ACADVL gene in these patients by sequence analysis. Results: Missense mutations within the ACADVL gene were identified in 3 of the patients. Conclusions: The locations of the altered amino acid residues within the crystal structure of VLCAD are on the surface of the molecule and may be involved in interactions with neighboring molecules. These findings support the importance of considering that mutations may be present in the ACADVL gene when a significant partial deficiency is found in CPTII activity, but no mutations in the CPT2 gene can be identified. Muscle Nerve, 2013
Detrusor overactivity in becker muscular dystrophy
Authors: Smith Matthew D. , Seth Jai H. , Hanna Michael G. , Panicker Jalesh N.
Published: August 2012

A 20‐year‐old man with normal motor milestones as an infant but subsequent progressive difficulty in walking in childhood, was genetically confirmed to have Becker muscular dystrophy (BMD) at age 13. He was independent in ambulation and activities of daily living. He was referred to the Department of Uro‐neurology for a 5‐year history of urinary urgency and incontinence. He would visit the toilet 10 times in the daytime and experience urinary urgency daily, often associated with incontinence. He did not report difficulties initiating voiding, stress incontinence, pain, or hematuria. There was no history of urinary tract infections. Muscle Nerve 47:464‐465, 2013
Synthesis and characterization of a new guar gum 4‐hydroxybenzoic acid resin and its use for the separation of heavy metal ions in industrial effluents
Authors: Singh A.V. , Kumawat Indraj Kumar
Published: August 2012

Hydroxybenzoic acid group has been incorporated onto guar gum by modified Porath's method of functionalization of polysaccharides. The newly synthesized guar gum 4‐hydroxybenzoic acid (GHBA) resin was characterized by Fourier‐transform infrared spectroscopy, elemental analysis, ion‐exchange capacity, column reusability, and physicochemical properties. The distribution coefficient (Kd) values and effect of pH on chelation of these metal ions using batch method were studied. The separations of mixture of Fe2+, Zn2+, Cu2+, Cd2+, and Pb2+ metal ions on GHBA resin on the basis of their distribution coefficient at various pH were also achieved using column chromatography. The effect of experimental parameters such as pH, treatment time, agitation speed, temperature, adsorbent dose, initial metal ion concentration, and flow rate on the removal of metal ions has been also studied. GHBA resin is effective adsorbents for the removal of different toxic metal ions from aqueous solutions and follows the order: Fe2+ > Zn2+ > Cu2+ > Cd2+ > Pb2+. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers
Nanocomposites of poly(ethylene oxide) and multiwall carbon nanotube prepared using an organic salt‐assisted dispersion technique
Authors: Ratna Debdatta , Jagtap Siddheshwar B. , Abraham Thomas
Published: August 2012

Poly (ethylene oxide) (PEO)/multiwall carbon nanotubes (MWCNT) nanocomposites were prepared by dispersion of MWCNTs in aqueous solution using half neutralized sodium salt of sebacic acid as a modifier. The physical interaction of half neutralized sodium salt of sebacic acid with MWCNT (cation‐π interaction) has been established by using Fourier transform infrared and Raman spectroscopic analyses. Such interaction helps in debundling the MWCNTs and resulted in a better dispersion in PEO matrix as confirmed by scanning electron microscopy and transmission electron microscopy. Addition of MWCNT significantly improves the storage modulus in rheological measurements as well as in dynamic mechanical thermal analysis. The crystallization behaviors of the composites made with the unmodified and modified MWCNTs were investigated. The modified MWCNT‐based composites shows large number of spherulite with smaller size compared to those observed in unmodified MWCNT‐based composite. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers
Formation of biodegradable polymeric fine particles by supercritical antisolvent precipitation process
Authors: Bakhbakhi Yousef , Asif Mohammad , Chafidz Achmad , Ajbar Abdelhamid
Published: August 2012

The supercritical antisolvent (SAS) precipitation process as a “green” alternative to specialty particles recrystallization was successfully used to generate poly(L‐lactide) acid (L‐PLA) from dichloromethane (DCM) solution using CO2 as antisolvent. The influence of main operating parameters on the synthesis of L‐PLA particles in the SAS process was methodically examined. In particular, antisolvent addition rate (30, 40, 50, and 60 g/min), temperature (35, 40°C, 45°C, and 50°C), solute concentration (50, 75, 100, and 150 mg/10 ml), and solution addition rate (1, 2.5, 5, and 7.5 ml/min). These parameters could be tuned to give a mean particle diameter of 0.62 μm. It was found using scanning electron microscopy and laser diffraction that increasing the antisolvent addition rate and the solution addition rate, while decreasing the temperature and solute concentration, led to a decrease in the L‐PLA mean particle diameter. Furthermore, a unimodal particle size distribution was obtained at the higher solution and antisolvent addition rates. Spherical‐like primary particles have been obtained in all the experimental runs; thus, no change of particle morphology with the process parameters has been noticed. These results manifested that SAS recrystallization process is a valuable technique to generate reproducibly polymer particles with controlled size and size distribution. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers
Effects of annealing time and temperature on the crystallinity and heat resistance behavior of injection‐molded poly(lactic acid)
Authors: Srithep Yottha , Nealey Paul , Turng Lih‐Sheng
Published: August 2012

The effects of annealing time and temperature on the crystallinity of injection‐molded poly(lactic acid) (PLA) were investigated using differential scanning calorimetry and wide‐angle x‐ray diffraction. Differential scanning calorimetry, tensile test, and dynamic mechanical analysis showed that an increase in crystallinity in the PLA parts from the annealing treatment offers several benefits such as a higher glass transition temperature, better heat resistance, and greater storage modulus and tensile strength. Based on the experimental data, the degree of crystallinity, annealing time, and annealing temperature were found to closely follow the time–temperature superposition relationship. Namely, a master curve could be constructed based on either the Williams–Landel–Ferry equation or the Arrhenius relationship by shifting the crystallinity isotherms in the logarithmic scale horizontally along the log‐time axis. This relationship provides a quantitative guideline for annealing postinjection‐molded PLA parts to improve the heat resistance and mechanical properties. An increase of over 17% and 26% in tensile strength was achieved at an annealing temperature of 80°C for 30 min and 65°C for 31 h, respectively. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers
Personality dysfunction and social functioning in schizophrenia
Authors: Newton‐Howes Giles , Marsh Reginald
Published: August 2012

Aim

To determine if personality dysfunction is associated with poorer clinical and social indicators in patients with schizophrenia.

Methodology

An observational study of patients with schizophrenia in psychiatric care assessed patient satisfaction with care, social functioning and psychopathology. Analysis of the relationship between personality and these three domains quantitatively assessed differences between patients with and without comorbid personality dysfunction. Diagnostic confounding was assessed using partial correlation coefficients.

Results

Forty‐five patients with schizophrenia were studied. In the schizophrenia group, personality dysfunction correlated with poorer social functioning but not poorer satisfaction with care. Linear regression found that the relationship between poorer social functioning and personality disorder in schizophrenia remained, taking other diagnoses and age into account. Partial correlation coefficients confirmed that this was no related to an overlap between personality and schizophrenia symptoms in this sample.

Conclusion

Personality dysfunction may negatively influence social functioning in patients with schizophrenia but does not appear to impact on patients' views of the care they receive. This is not due to the potential for diagnostic confounding between schizophrenia and personality disorder. Further research using larger samples is needed to confirm this association. Copyright © 2012 John Wiley & Sons, Ltd.
On‐line CE/ESI/MS interfacing: Recent developments and applications in proteomics
Authors: Krenkova Jana , Foret Frantisek
Published: August 2012

After shining as the ultimate separation – sequencing technique used for the successful completion of the Human Genome Project, in the early 2000s CE experienced lowered popularity among separation scientists. The renewed interest in recent years relates to the separation needs, especially in proteomics, metabolomics, and glycomics, where CE complements liquid chromatography techniques. This interest is further boosted by the regulators requiring additional separation techniques for characterization of newly developed pharmaceuticals. This paper gives a short overview of recent developments in the on‐line interfacing of CE separation techniques with electrospray ionization/mass spectrometric analysis. Both the instrumentation and selected CE/ESI/MS applications including analyses of peptides, proteins, and glycans are discussed with the stress on research published in the past 3 years. Techniques related to the proteomic and glycomic analyses such as sample preconcentration, on‐line protein digestion, and analyte derivatization prior CE/ESI/MS analysis are also included.
Effects of stereocomplexation on the physicochemical behavior of PLA/PEG block copolymers in aqueous solution
Authors: Wu Xiaohan , Li Suming , Ghzaoui Abdeslam El
Published: August 2012

A series of polylactide/poly(ethylene glycol) (PLA/PEG) block copolymers were synthesized by ring‐opening polymerization of L‐ or D‐lactide in the presence of mono‐ or di‐hydroxyl PEG. The effects of stereocomplexation on the physicochemical behavior of PLA/PEG copolymers in aqueous solution were investigated by varying the degree of stereocomplexation or PLLA/PEG to PDLA/PEG ratio. In mixture solutions of insoluble and soluble copolymers, stereocomplexation strongly affects the solubility of the copolymers. In mixture solutions of soluble copolymers, both the size and aggregation number (Nagg) of the aggregates vary as a function of the degree of stereocomplexation. It is suggested that the size variation of the aggregates with increasing the degree of stereocomplexation is dependent on Nagg changes which are determined by two effects: the self‐adjusting of the aggregates so as to minimize the free energy and thus to increase the Nagg, and the kinetics of aggregation which tend to form more aggregates and thus to decrease the Nagg. Combination of the two opposite effects well explains the diverse variations of Nagg and size of the aggregates as a function of the degree of stereocomplexation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Synthesis and characterization of C60/polyaniline composites from interfacial polymerization
Authors: Wang Qiguan , Wang Sumin , Li Jianping , Moriyama Hiroshi
Published: August 2012

C60/polyaniline (PANI) nanocomposites have been synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in the presence of C60 by using an interfacial reaction. When compared with the pure PANI nanofibers from the similar process, the diameter of the obtained C60/PANI nanofibers was increased because of the encapsulation of C60 into PANI during aniline polymerization, which resulted from the charge‐transfer interactions between C60 and aniline fragment in PANI. In addition, the resulting C60/PANI nanocomposites synthesized from the low initial C60/aniline molar ratio (less than 1:25) showed the homogenous morphology composed of fiber network structures, which has an electrical conductivity as high as 1.1 × 10−4 S/cm. However, the C60/PANI nanocomposites from the higher initial C60/aniline molar ratio (more than 1:15) showed the nonuniformly distributed morphology, and the electrical conductivity was decreased to 3.5 × 10−5 S/cm. Moreover, the C60/PANI nanocomposites from the interfacial reaction showed a higher value of electrical conductivity than the mechanically mixed C60/PANI blends with the same C60 content, because of the more evenly distributed microstructures. FTIR, UV–vis, and CV data confirmed the presence of C60 and the significant charge‐transfer interactions in the resultant nanocomposites, which was responsible for the morphology development of the C60/PANI and the variation of the electrical conductivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Supporting ‘work‐related goals’ rather than ‘return to work’ after cancer? A systematic review and meta‐synthesis of 25 qualitative studies
Authors: Wells Mary , Williams Brian , Firnigl Danielle , Lang Heidi , Coyle Joanne , Kroll Thilo , MacGillivray Steve
Published: August 2012

Background

This study aimed to systematically review and synthesise qualitative studies of employment and cancer.

Methods

A rigorous systematic review and meta‐synthesis process was followed. A total of 13 233 papers were retrieved from eight databases; 69 were deemed relevant following title and abstract appraisal. Four further publications were identified via contact with key authors. Screening of full texts resulted in the retention of 25 publications from six countries, which were included in the synthesis.

Results

Studies consistently indicate that for people with cancer, ‘work’ forms a central basis for self‐identity and self‐esteem, provides financial security, forms and maintains social relationships, and represents an individual's abilities, talents and health. Work is therefore more than paid employment. Its importance to individuals rests on the relative value survivors place on these constituent functions. The desirability, importance and subsequent interpretation of individuals' experience of ‘return to work’ appears to be influenced by the ways in which cancer affects these functions or goals of ‘work’. Our synthesis draws these complex elements into a heuristic model to help illustrate and communicate these inter‐relationships.

Conclusion

The concept of ‘return to work’ may be overly simplistic, and as a result, misleading. The proposed benefits previously ascribed to ‘return to work’ may only be achieved through consideration of the specific meaning and role of work to the individual. Interventions to address work‐related issues need to be person‐centred, acknowledging the work‐related outcomes that are important to the individual. A conceptual and operational shift towards supporting survivors to identify and achieve their ‘work‐related goals’ may be more appropriate. Copyright © 2012 John Wiley & Sons, Ltd.
Protein folding rates and thermodynamic stability are key determinants for interaction with the Hsp70 chaperone system
Authors: Sekhar Ashok , Lam Hon Nam , Cavagnero Silvia
Published: August 2012

The Hsp70 family of molecular chaperones participates in vital cellular processes including the heat shock response and protein homeostasis. E. coli's Hsp70, known as DnaK, works in concert with the DnaJ and GrpE co‐chaperones (K/J/E chaperone system), and mediates cotranslational and post‐translational protein folding in the cytoplasm. While the role of the K/J/E chaperones is well understood in the presence of large substrates unable to fold independently, it is not known if and how K/J/E modulates the folding of smaller proteins able to fold even in the absence of chaperones. Here, we combine experiments and computation to evaluate the significance of kinetic partitioning as a model to describe the interplay between protein folding and binding to the K/J/E chaperone system. First, we target three nonobligatory substrates, that is, proteins that do not require chaperones to fold. The experimentally observed chaperone association of these client proteins during folding is entirely consistent with predictions from kinetic partitioning. Next, we develop and validate a computational model (CHAMP70) that assumes kinetic partitioning of substrates between folding and interaction with K/J/E. CHAMP70 quantitatively predicts the experimentally measured interaction of RNase HD as it refolds in the presence of various chaperones. CHAMP70 shows that substrates are posed to interact with K/J/E only if they are slow‐folding proteins with a folding rate constant kf <50 s−1, and/or thermodynamically unstable proteins with a folding free energy ΔG0UN ≥−2 kcal mol−1. Hence, the K/J/E system is tuned to use specific protein folding rates and thermodynamic stabilities as substrate selection criteria.
Influence of temperature on formation of perfect tau fragment fibrils using PRIME20/DMD simulations
Authors: Cheon Mookyung , Chang Iksoo , Hall Carol K.
Published: August 2012

We investigate the fibrillization process for amyloid tau fragment peptides (VQIVYK) by applying the discontinuous molecular dynamics method to a system of 48 VQIVYK peptides modeled using a new protein model/force field, PRIME20. The aim of the article is to ascertain which factors are most important in determining whether or not a peptide system forms perfect coherent fibrillar structures. Two different directional criteria are used to determine when a hydrogen bond occurs: the original H‐bond constraints and a parallel preference H‐bond constraint that imparts a slight bias towards the formation of parallel versus antiparallel strands in a β‐sheet. Under the original H‐bond constraints, the resulting fibrillar structures contain a mixture of parallel and antiparallel pairs of strands within each β‐sheet over the whole fibrillization temperature range. Under the parallel preference H‐bond constraints, the β‐sheets within the fibrillar structures are more likely to be parallel and indeed become perfectly parallel, consistent with X‐ray crystallography, at a high temperature slightly below the fibrillization temperature. The high temperature environment encourages the formation of perfect fibril structures by providing enough time and space for peptides to rearrange during the aggregation process. There are two different kinetic mechanisms, template assembly with monomer addition at high temperature and merging/rearrangement without monomer addition at low temperature, which lead to significant differences in the final fibrillar structure. This suggests that the diverse fibril morphologies generally observed in vitro depend more on environmental conditions than has heretofore been appreciated.
Phase 3 clinical trial investigating the effect of selenium supplementation in men at high‐risk for prostate cancer
Authors: Algotar Amit M. , Stratton M. Suzanne , Ahmann Frederick. R. , Ranger‐Moore James , Nagle Raymond B. , Thompson Patricia A. , Slate Elizabeth , Hsu Chiu H. , Dalkin Bruce L. , Sindhwani Puneet , Holmes Michael A. , Tuckey John A. , Graham David. L. , Parnes Howard L. , Clark Lawrence C. , Stratton Steven P.
Published: August 2012

PURPOSE

This study was conducted to investigate the effect of Se supplementation on prostate cancer incidence in men at high risk for prostate cancer.

METHODS

A Phase 3 randomized, double‐blind, placebo‐controlled clinical trial was conducted in 699 men at high risk for prostate cancer (prostate specific antigen (PSA) >4 ng/ml and/or suspicious digital rectal examination and/or PSA velocity >0.75 ng/ml/year), but with a negative prostate biopsy. Participants were randomized to receive daily oral placebo (N = 232), 200 µg selenium (N = 234), or 400 µg selenium (N = 233) as selenized yeast. They were followed every 6 months for up to 5 years. The time to diagnosis of prostate cancer was compared between treatment groups using the Cox proportional hazards model.

RESULT

Compared to placebo, the hazard ratios [95% confidence intervals] for risk of developing prostate cancer in the selenium 200 µg/day or the selenium 400 µg/day group were 0.94 [0.52, 1.7] and 0.90 [0.48, 1.7], respectively. PSA velocity in the selenium arms was not significantly different from that observed in the placebo group (P = 0.18 and P = 0.17, respectively).

CONCLUSION

Selenium supplementation appeared to have no effect on the incidence of prostate cancer in men at high risk. In conjunction with results of other studies, these data indicate that selenium supplementation may not have a role in prostate cancer chemoprevention. Prostate 73: 328–335, 2013. © 2012 Wiley Periodicals, Inc.
Management discipline
Authors: Forest Jerry J.
Published: August 2012

Conduct of operations (COO) concerns how work is performed in a manufacturing unit with the overall objective of producing repeated and desired results. COO reduces the likelihood of human error. The term discipline is often used to describe how to bring a consistent approach to various operations to minimize errors.

This article introduces a new model of COO based on a Steven Covey performance model, where improved performance is a function of (a) knowing what to do, (b) knowing how to do it, and (c) wanting to do it. Our new model (described in this article) applies this Covey principle to facilitate operating disciple, engineering disciple, and management discipline. Each element of COO should be in place to produce consistent results and reduce human error. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012.
Diamond solution‐gated field effect transistors: Properties and bioelectronic applications
Authors: Dankerl Markus , Hauf Moritz V. , Stutzmann Martin , Garrido Jose A.
Published: August 2012

Solution gate field‐effect transistors (SGFETs) based on diamond show great potential in biosensing and bioelectronics thanks to the advantageous combination of physical and chemical properties offered by this carbon material. In this contribution, we discuss fundamental aspects of diamond SGFETs as well as a number of important applications. We first demonstrate how the p‐type charge accumulation at the hydrogen‐terminated diamond surface can be controlled with an electrolyte gate, forming the basis of diamond SGFETs. For a proper understanding of the operation of the surface conductive diamond SGFETs, it is essential to consider the effect of such a hydrophobic surface on the structure of water at the diamond/electrolyte interface. The electronic transport in the p‐type surface conductive channel is studied with Hall‐effect experiments performed in an electrolyte in order to elucidate the limiting scattering mechanisms for carriers at the diamond surface. We present the fabrication and characterization of arrays of solution‐gated field effect transistors based on single crystalline diamond revealing attractive sensor properties such as high sensitivity and low electronic noise. These diamond SGFETs are investigated as sensors of pH and ionic strength of the electrolyte. Further, we demonstrate the use of these devices for the detection of neurotransmitters when the sensor's active area is functionalized with suitable enzymes. Finally, we show the application of diamond SGFETs for the extracellular recording of the electrical activity of electrogenic cells, thus paving the way for the development of novel diamond‐based bio‐hybrid systems with the potential to facilitate further progress in the understanding of the cell–semiconductor interface.
On covering expander graphs by hamilton cycles
Authors: Glebov Roman , Krivelevich Michael , Szabó Tibor
Published: August 2012

The problem of packing Hamilton cycles in random and pseudorandom graphs has been studied extensively. In this paper, we look at the dual question of covering all edges of a graph by Hamilton cycles and prove that if a graph with maximum degree Δ satisfies some basic expansion properties and contains a family of edge disjoint Hamilton cycles, then there also exists a covering of its edges by Hamilton cycles. This implies that for every α > 0 and every there exists a covering of all edges of G(n,p) by Hamilton cycles asymptotically almost surely, which is nearly optimal.Copyright © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 44, 183‐200, 2014
A New Approach to Assess Gold Nanoparticle Uptake by Mammalian Cells: Combining Optical Dark‐Field and Transmission Electron Microscopy
Authors: Rosman Christina , Pierrat Sebastien , Henkel Andreas , Tarantola Marco , Schneider David , Sunnick Eva , Janshoff Andreas , Sönnichsen Carsten
Published: August 2012

Toxicological effects of nanoparticles are associated with their internalization into cells. Hence, there is a strong need for techniques revealing the interaction between particles and cells as well as quantifying the uptake at the same time. For that reason, herein optical dark‐field microscopy is used in conjunction with transmission electron microscopy to investigate the uptake of gold nanoparticles into epithelial cells with respect to shape, stabilizing agent, and surface charge. The number of internalized particles is strongly dependent on the stabilizing agent, but not on the particle shape. A test of metabolic activity shows no direct correlation with the number of internalized particles. Therefore, particle properties besides coating and shape are suspected to contribute to the observed toxicity.
Coordinated Action in the Massively Multiplayer Online Game World of Warcraft
Authors: Williams J. Patrick , Kirschner David
Published: August 2012

In tandem with the technological advancement of immersive virtual environments, digital games have evolved into complex social worlds where people play collaboratively to achieve individual‐ and group‐oriented goals. The massively multiplayer online games genre has received international attention for the large numbers of users that commit a significant amount of time and effort to online play. Play styles within such game worlds are diverse, but “raiding” is generally considered among gamers and scholars alike to be the most challenging form of collaborative play. Like other forms of social activity, raiding is predicated on players' abilities to successfully coordinate individual lines of action. Yet the vast majority of raiders are not physically copresent during their collaborative efforts. Using Couch's theory of coordinated action as an interpretive frame, we explore the computer‐mediated process of raiding in the massively multiplayer online game World of Warcraft by analyzing ethnographic data and audio/visual recordings of gameplay. Our study expands Couch's theory of coordinated action in two ways. First, we demonstrate how individuals and groups simultaneously engage in multiple forms of coordinated activity (e.g., conflict and cooperation). Second, we reveal two semiotic layers of coordinated action—the “subject‐subject” (i.e., intersubjective) layer that is facilitated through the game's user interface, and the “subject‐object” layer that comprises players' interactions with the user interface itself. Our study thus considers the potential of Couch's theory for the study of computer‐mediated communication and nonhumans in interaction.
Repelling the “Rutter”: Social Differentiation Among Rural Teenagers
Authors: Morris Edward W.
Published: August 2012

This paper examines low‐income white rural teenagers' management of race and class‐based inequality. It analyzes how these teenagers constructed boundaries to distinguish themselves from outsiders, but also to distinguish themselves from the local abject category of “rutter.” The findings reveal hidden interconnections between race and class in interactional practice, and highlight local processes of differentiation through which actors attempt to deflect stigma and attain credibility. The paper discusses how interactional mechanisms such as “internal othering” and “stigma‐theory” bolster race and class credibility, but reproduce inequality.
The effects of tetanic stimulation on plasticity of remote synapses in the hippocampus‐perirhinal cortex‐amygdala network
Authors: Supcun Beste , Ghadiri Maryam Khaleghi , Zeraati Maryam , Stummer Walter , Speckmann Erwin‐Josef , Gorji Ali
Published: August 2012

In the temporal lobe, multiple synaptic pathways reciprocally link different structures. These multiple pathways play an important role in the integrity of the function of the temporal lobe and malfunction in this network has been suggested to underlie some neurological disorders such as epilepsy. To test whether the induction of long‐term potentiation (LTP) in one temporal lobe structure would modulate functional synaptic plasticity in other structures of this network, tetanic stimulation was applied to the white matter of the perirhinal cortex, Schaffer collaterals of the hippocampus, or the external capsule in combined rat amygdala–hippocampus–cortex slices. This tetanic stimulation was accompanied by enhancement of the evoked field potential slope in the third layer of perirhinal cortex, hippocampal CA1 area, and the lateral amygdala. Induction of LTP in each of these structures was concomitant with increased evoked field potentials in the neighboring structures. Surgical disconnection of anatomical pathways between these structures inhibited this concomitant enhancement of theevoked field potential slope. Both NMDA and AMPA glutamate sub‐receptors were involved in changes of synaptic plasticity elicited by induction of LTP in the neighboring structures. The present data indicate a reciprocal control among the perirhinal cortex, the amygdala, and the hippocampus plasticity. This could be important for the formation and retention of the medial temporal lobe‐dependent memory and may play a role in the involvement of all different regions of the temporal lobe in pathological conditions such as epilepsy that affect this brain structure. Synapse 66:965–974, 2012. © 2012 Wiley Periodicals, Inc.