bluuebunny/crossref_metadata_2025 huggingface dataset:
RELATIONSHIPS OF REASONING AND WRITING SKILLS TO GRE ANALYTICAL ABILITY SCORES
Authors: Carlson Sybil B.
Published: September 2014

The major objective of the study was to gain more information about the reasoning skills tapped by the GRE analytical measure by examining how performance on its constituent item types relate to alternative criteria. A second objective was to ascertain the extent to which additional information on examinees' analytical skills might be obtained from further analyses of their writing performance. The data base for this study consisted of 406 writing samples, prepared by 203 students who had recently taken the GRE General Test for admission to institutions of higher education in the United States. The bulk of these data were collected for research funded by the GRE Board and TOEFL Policy Council, in which the writing samples were scored to reflect writing skills; these scores were related to scores on the GRE General Test and the TOEFL, as well as other measures. In order to supplement the sample of native speakers, additional writing samples were collected from 77 native speakers of English and 3 native speakers of Arabic who had recently taken the GRE General Test and who were in their first year of graduate education in the United States. The final sample included subsamples of nonnative speakers of English (6 Arabic, 73 Chinese, 35 Spanish) and the subsample of 89 native speakers of English.

The objectives of this study were accomplished by developing several scoring methods that focused on the reasoning skills that are reflected in these papers. These scores, in addition to the scores for writing skills, were related to item type subscores derived from the verbal and analytical reasoning sections of the GRE General Test in order to determine if these item types relate differently to judgments of examinees' thinking and writing skills.

Three scoring methods did not appear to provide additional information beyond what is obtained from the analytical reasoning and verbal sections of the GRE General Test. The Moss scheme, however, yielded scores that were relatively independent of these sections of the GRE. It is possible that these scores tapped verbal reasoning skills that are not assessed by the GRE General Test, but further research is needed to determine whether they represent important developed abilities. Writer's Workbench computerized text analyses suggested that the different writing tasks elicited different kinds of writing performance, and that the writing performance of students representing different native language groups may vary in complex ways in response to these tasks.
THE EQUIVALENCE OF SCORES FROM AUTOMATED AND CONVENTIONAL EDUCATIONAL AND PSYCHOLOGICAL TESTS
Authors: Mazzeo John , Harvey Anne L.
Published: September 2014

A literature review was conducted to determine the current state of knowledge concerning the effects of the computer administration of standardized educational and psychological tests on the psychometric properties of these instruments. Studies were grouped according to a number of factors relevant to the administration of tests by computer. Based on the studies reviewed, we arrived at the following conclusions:

The rate at which test‐takers omit items in an automated test may differ from the rate at which they omit items in a conventional presentation.

Scores on tests from automated versions of personality inventories such as the Minnesota Multiphasic Personality Inventory are lower than scores obtained in the conventional testing format. These differences may result in part from differing omit rates, as described above, but some of the differences may be caused by other factors.

Scores from automated versions of speed tests are not likely to be comparable with scores from paper‐and‐pencil versions.

The presentation of graphics in an automated test may have an effect on score equivalence. Such effects were obtained in studies using the Hidden Figures Test. However, in studies with three Armed Services Vocational Aptitude Battery (ASVAB) tests, effects were not found.

Tests containing items based on reading passages can become more difficult when presented on a CRT. This was demonstrated in a single study with the ASVAB tests.

The possibility of such asymmetric practice effects may make it wise to avoid conducting equating studies based on single‐group counterbalanced designs.
THE INFORMATION MATRIX IN LATENT‐VARIABLE MODELS1
Authors: Mislevy Robert J. , Sheehan Kathleen M.
Published: September 2014

The information matrix for the parameters in a latent‐variable model is bounded from above by the information that would obtain if the values of the latent variables could also be observed. The difference is the “missing information.” This paper discusses the structure of the information matrix, and characterizes the degree to which missing information can be recovered by exploiting collateral variables for respondents. The results are illustrated with data from the Armed Services Vocational Aptitude Battery.
EMPIRICAL BAYES METHODS: A TOOL FOR EXPLORATORY ANALYSIS
Authors: Braun Henry I.
Published: September 2014

Empirical Bayes (EB) on hierarchical linear models are frequently utilized in practice. This paper provides an overview of parametric EB methods with special emphasis on their application in data‐analytic settings. A variety of models with different levels of complexity are described. Comparisons of performance with other methods are illustrated using test data. Applications to validity generalization and survival analysis are also discussed.
RANDOMIZATION‐BASED INFERENCES ABOUT LATENT VARIABLES FROM COMPLEX SAMPLES
Authors: Mislevy Robert J.
Published: September 2014

Standard procedures for drawing inferences from complex samples do not apply when the variable of interestθcannot be observed directly, but must be inferred from the values of secondary random variables that depend onθstochastically. Examples are examinee proficiency variables in item response theory models and class memberships in latent class models. This paper uses Rubin's “multiple imputation” approach to approximate sample statistics that would have been obtained, hadθbeen observable. Associated variance estimates account for uncertainty due to both the sampling of respondents from the population and the latency ofθ. The approach is illustrated with artificial examples and with data from the 1984 National Assessment for Educational Progress reading survey.
Influence of atmospheric pressure plasma treatment on mechanical proprieties of enamel and sealant bond strength
Authors: Teixeira Hellen S. , Coelho Paulo G. , Duarte Simone , Janal Malvin N. , Silva Nelson , Thompson Van P.
Published: September 2014

Objectives

To define the effect of APP treatments on the mechanical properties of enamel and on its ability to promote sealant bonding to unetched enamel.

Methods

Human molar teeth were sectioned exposing flat enamel regions at the buccal and lingual surfaces. The specimens were divided into two substrate groups (etched and unetched) and distributed over three surface treatments

(i) 5 slm Argon APP treatment, NaOH surface treatment, and (iii) compressed air application (control). The Enamel surfaces were characterized by SEM, IFM, and Goniometer instruments. For the mechanical tests nanoindentation and microshear bond strength were employed. Initial data evaluation comprised normality verification (SPS S software) and variance checking and the appropriated statistical analysis model employed. For all statistical inferences, significance was set at 0.05.

Results

SE was significantly higher for the etched and unetched group treated with Plasma relative to the NaOH and control groups. Nanoindentation testing determined that Rank hardness was significantly higher in the control and Plasma group relative to NaOH for the etched group. Rank Elastic Modulus was significantly higher on Control groups relative to NaOH and Plasma groups for the etched substrate. No difference was detected between treatments for the unetched group. For the µSBS test, we observed that APP treatment on etched and unetched enamel increased bonds significantly (p < 0.001).

Conclusions

This study demonstrated that APP increased SE, surface wettability and bond strength between enamel and sealants potentially serving as a substitute for conventional acid etching procedures or as an adjuvant for self‐etch sealants. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1082–1091, 2015.
Simultaneous Determination of Nitrite and Hydrogen Peroxide Using Hemoglobin Modified Pencil Lead Electrode as a Novel Biosensor: Application to the Analysis of Mother’s Milk
Authors: Majidi Mir Reza , Pournaghi‐Azar Mohammad Hossein , Saadatirad Afsaneh , Alipour Esmaeel
Published: September 2014

In the present paper simultaneous determination of nitrite and hydrogen peroxide using hemoglobin modified pencil lead electrode (Hb/PLE) prepared by a simple and rapid electroless method was described. In the first part of the work the reduction of NO2 and H2O2 at the modified electrode was investigated by cyclic voltammetry. Then under optimal conditions using differential pulse voltammetry, the biosensor could be used for the determination of H2O2 at concentration ranging from 5 to 240 M and NO2 at concentration ranging from 10 to 240 M. The detection limits were 3×10−6 and 5×10−6 M, for NO2 and H2O2 respectively. Differential pulse voltammetry also used for the simultaneous determination of NO2 and H2O2. This modified electrode successfully used for the determination of NO2 and H2O2 in tap water and mother’s milk samples.
Survival Modeling of Discontinuation From Psychotherapy: A Consumer Decision‐Making Perspective
Authors: Krishnamurthy Partha , Khare Adwait , Klenck Suzanne C. , Norton Peter J.
Published: September 2014

Objective

This study examines discontinuation of psychotherapy from a consumer decision‐making perspective. Two plausible predictors, the level of illness and rate of progress from where the patient started, were examined as predictors of treatment discontinuation.

Method

Using data from 139 patients (45.5% women; mean age = 32.18 years) participating in a 12‐week transdiagnostic cognitive‐behavioral therapy program for anxiety, weekly assessments of anxiety severity were examined to investigate the extent to which level of anxiety and rate of improvement predicted treatment discontinuation.

Results

Support was found for a significant interaction effect wherein at higher anxiety levels, rate of progress was less associated with discontinuation than at lower anxiety levels.

Conclusion

Faster rates of anxiety reduction are associated with greater likelihood of discontinuation when the client is at a lower level of anxiety, whereas rate of improvement is less associated with discontinuation if there remains continued impairment and room for improvement. As such, clinicians should monitor rates of improvement throughout treatment to help identify and evaluate patients at increased risk of premature discontinuation.
One‐Pot Three‐Component Synthesis of Pyrazolyl‐thiadiazinyl‐2H‐chromen‐2‐one Derivatives
Authors: Pavurala Sreenu , Vaarla Krishnaiah , Vedula Rajeswar Rao
Published: September 2014

An efficient novel one‐pot synthesis of pyrazolyl‐thiadiazinyl‐2H‐chromen‐2‐ones. In this process, an equimolar mixture of substituted 3‐(2‐bromoacetyl)‐2H‐chromen‐2‐ones, thiocarbohydrazide and pentane‐2,4‐dione were taken in absolute ethanol. All these synthesized compounds were characterized by their analytical and spectral data.
Altered proteolytic activity and expression of MMPs and aggrecanases and their inhibitors in Kashin–Beck disease
Authors: Chen Jinghong , Luo Mingxiu , Wang Wei , Zhang Zentie , He Ying , Duance Victor C. , Hughes Clare E. , Caterson Bruce , Cao Junling
Published: September 2014

Kashin–Beck disease (KBD) is a chronic, deforming endemic osteoarticular disease with altered metabolism of the cartilage matrix. Matrix metalloproteinases (MMPs), aggrecanases (ATAMTSs), and their inhibitors (TIMPs) play important roles in cartilage formation and matrix degradation. This study investigated these proteases and inhibitors in young KBD cartilage. The percentages of chondrocytes staining for MMP‐1/‐13 and MMP‐generated DIPEN neoepitope, aggrecanase‐generated ITEGE neoepitope in aggrecan in KBD patients were significantly higher than in controls. However, TIMP‐1 was significantly less numerous than in controls in the superficial and middle zones of KBD samples, the percentage of chondrocytes staining for the TIMP‐2 was significantly higher than in controls. Staining for MMP‐1/‐13 and, TIMP‐1/‐2 in KBD patients was prominent in the superficial zone and the middle zone of articular cartilage. Staining for ITEGE and DIPEN neoepitopes in KBD samples was prominent in the superficial zone and the middle zone of articular cartilage. The strongest staining for the MMP and aggrecanase‐generated neoepitopes was adjacent to areas of chondronecrosis. These results indicated that KBD cartilage destruction depends on collagen‐ and aggrecan‐degrading proteases such as collagenases (MMP‐1/‐13), as well as aggrecanases. Increased TIMP‐2 level adjacent to necrotic areas suggest that attempted repair mechanism are also activated. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:47–55, 2015.
Raman spectroscopic investigations on transition‐metal dichalcogenides MX2 (M = Mo, W; X = S, Se) at high pressures and low temperature
Authors: Bhatt Sandip V. , Deshpande M. P. , Sathe Vasant , Rao Rekha , Chaki S. H.
Published: September 2014

Transition‐metal dichalcogenides have been investigated using Raman spectroscopy both being off‐resonance and in resonance. The first‐order Raman spectra of MoS2, MoSe2, WS2 and WSe2 single crystal synthesized by vapor transport technique have been studied as a function of hydrostatic pressure (0–20 GPa) and temperature (80–300 K). Isobaric and isothermal mode‐Grüneisen parameters have been determined from the temperature and pressure‐dependent Raman spectra. The pressure dependence of the chalcogen–chalcogen and metal–chalcogen force constant has been obtained using a central force model. Separation of the temperature dependence of Raman mode wavenumbers into quasi‐harmonic and purely anharmonic contributions using measured high‐pressure Raman data allows us to extract the changes in the phonon wavenumbers arising exclusively due to anharmonic interactions. Copyright © 2014 John Wiley & Sons, Ltd.
Micro‐Raman spectroscopy and ancient ceramics: applications and problems
Authors: Medeghini Laura , Lottici Pier Paolo , De Vito Caterina , Mignardi Silvano , Bersani Danilo
Published: September 2014

Micro‐Raman spectroscopy is applied for the study of two classes of ancient ceramic artefacts showing different features and technological background, i.e. the fine‐grain Black Gloss Ware from Motya (Sicily, Italy) and the coarse‐grain pottery from Khirbet al‐Batrawy (Jordan). The characterization of the mineralogical composition of these ceramics allows exploring the firing conditions and the manufacturing process. In particular, μ‐Raman spectroscopy permits to define the mineralogical assemblage of the bulk of both groups of ceramic samples as well as the nature of the black gloss and superficial decorations. Moreover, μ‐Raman spectroscopy, allowing the identification of mineral phases in traces and describing as a consequence a more detailed mineralogical assemblage, can contribute to address issues concerning the provenance of the raw materials. The evaluation of the Raman results compared to those obtained by optical microscopy, X‐ray diffraction and electron microscopy highlights that Raman spectroscopy shows a great potential in the analysis of coarse‐grain and low fired ceramics, whereas it proves its limits in the analysis of fine and vitrified pottery class where the intergrowth of glass and crystalline phases provides Raman spectra not so easily interpretable. Copyright © 2014 John Wiley & Sons, Ltd.
Analysis of The Intrahepatic Ductular Reaction and Progenitor Cell Responses in Hepatitis C Virus Recurrence After Liver Transplantation
Authors: Prakoso Emilia , Tirnitz-Parker Janina E. E. , Clouston Andrew D. , Kayali Zeid , Lee Aimei , Gan Eng K. , Ramm Grant A. , Kench James G. , Bowen David G. , Olynyk John K. , McCaughan Geoffrey W. , Shackel Nicholas A.
Published: September 2014

Fibrosis in livers with hepatitis C virus (HCV) recurrence after liver transplantation (LT) can be rapidly progressive, and the mechanisms underlying this process are poorly understood. In livers with HCV infections in the non-LT setting, there is a significant relationship between the development of structures known as the ductular reaction (DR), hepatic progenitor cells (HPCs), and fibrosis. This study characterizes the DR, HPCs, and fibrosis associated with HCV recurrence after LT. Immunohistochemistry and confocal microscopy were used to characterize the DR, HPC, and fibrosis in liver biopsy specimens. Key findings were confirmed in a separate, independent cohort. The initial characterization cohort had 194 biopsy samples from 105 individuals with HCV recurrence after LT. The immunophenotype, morphology, and location of the DR were consistent with an HPC origin. The DR correlated with intrahepatic fibrosis (r

s
= 0.529, P < 0.001) and the number of activated hepatic stellate cells (HSCs; r

s
= 0.446, P < 0.001). There was an early occurrence of hepatocyte replicative arrest as well as increased hepatocyte proliferation that correlated with the DR (r

s
= 0.295, P < 0.001). Replicative arrest preceded hepatocyte proliferation in early-stage injury. Hepatocyte proliferation decreased with advanced fibrosis; in contrast, the extent of the DR and the number of activated HSCs continued to increase. In the second cohort of 37 individuals, the DR and the number of HPCs similarly correlated with fibrosis and inflammation after LT. In conclusion, this is the first characterization of the DR in HCV-associated liver injury after LT. There was a significant correlation between the DR and the development of progressive fibrosis in HCV recurrence. These results suggest a pivotal role for both the DR and the HPC responses in the aggressive fibrosis seen with HCV recurrence after LT. Liver Transpl 20:1508–1519, 2014. © 2014 AASLD.
Sensate anterolateral thigh perforator flap for ischiatic sores reconstruction in meningomyelocele patients
Authors: Santanelli Di Pompeo Fabio , Longo Benedetto , Pagnoni Marco , Laporta Rosaria
Published: September 2014

Recidivating pressure sores are a frequent complication in meningomyelocele patients because of their limitation in motility and their scarce ability to monitor the pressure applied on insensate areas while seated. We report the utilization of the sensate pedicled anterolateral thigh perforator flap for reconstruction of ischiatic sores in meningomyelocele patients. Between May 2011 and September 2013, five patients underwent transfer of a sensate pedicled anterolateral thigh flap, by an intermuscular passageway through the upper thigh, to reach the ischial defect. Flap was properly harvested from the thigh after assessment of the lateral cutaneous femoral nerve sensitive area with the Pressure‐Specified Sensory Device. In all cases the flap reached the ischial defect harmlessly, healing was uneventful with no immediate nor late complications. Each patient showed persistence of sensitivity at the reconstructed area and no recurrent ischiatic sore was observed at mean follow‐up of 26.4 months. The sensate pedicled anterolateral thigh flap is a valuable solution for coverage of recurrent ischial sores in meningomyelocele patients, in which pressure consciousness is fundamental. The intermuscular passageway allows to reduce the distance between flap's vascular pedicle origin and the ischial defect, hence to use the more reliable skin from the middle third of the anterolateral thigh. © 2014 Wiley Periodicals, Inc. Microsurgery 35:279–283, 2015.
Interaction of Flaviviruses with Reproduction Inhibitors Binding in β‐OG Pocket: Insights from Molecular Dynamics Simulations
Authors: Dueva Evgenia V. , Osolodkin Dmitry I. , Kozlovskaya Liubov I. , Palyulin Vladimir A. , Pentkovski Vladimir M. , Zefirov Nikolay S.
Published: September 2014

Flaviviral diseases, including dengue fever, West Nile fever, yellow fever, tick‐borne encephalitis, Omsk haemorrhagic fever, and Powassan encephalitis, threaten human health all over the world. Lack of effective antivirals targeting replication cycle of flaviviruses makes the search of such compounds a challenging task. Recently we have identified a reproduction inhibitor effective against tick‐borne encephalitis virus and Powassan virus (POWV) (ACS Med. Chem. Lett., 2013, 4, 869–874). To enable using this inhibitor as a template for 3D pharmacophore search, a biologically active conformation of this molecule should have been established. Here we performed molecular dynamics simulations of the complexes between the different enantiomers of the inhibitor and POWV envelope (E) proteins, putative targets of the inhibitor, in the different protonation states corresponding to the different stages of membrane fusion process. Several stable conformations of the inhibitor were identified, opening routes for further design of more advanced molecules.
Computational Prediction of DrugTarget Interactions Using Chemical, Biological, and Network Features
Authors: Cao Dong‐Sheng , Zhang Liu‐Xia , Tan Gui‐Shan , Xiang Zheng , Zeng Wen‐Bin , Xu Qing‐Song , Chen Alex F
Published: September 2014

Drugtarget interactions (DTIs) are central to current drug discovery processes. Efforts have been devoted to the development of methodology for predicting DTIs and drugtarget interaction networks. Most existing methods mainly focus on the application of information about drug or protein structure features. In the present work, we proposed a computational method for DTI prediction by combining the information from chemical, biological and network properties. The method was developed based on a learning algorithm‐random forest (RF) combined with integrated features for predicting DTIs. Four classes of drugtarget interaction networks in humans involving enzymes, ion channels, G‐protein‐coupled receptors (GPCRs) and nuclear receptors, are independently used for establishing predictive models. The RF models gave prediction accuracy of 93.52 %, 94.84 %, 89.68 % and 84.72 % for four pharmaceutically useful datasets, respectively. The prediction ability of our approach is comparative to or even better than that of other DTI prediction methods. These comparative results demonstrated the relevance of the network topology as source of information for predicting DTIs. Further analysis confirmed that among our top ranked predictions of DTIs, several DTIs are supported by databases, while the others represent novel potential DTIs. We believe that our proposed approach can help to limit the search space of DTIs and provide a new way towards repositioning old drugs and identifying targets.
Intensity modulation using chirped fiber bragg grating as an edge filter for temperature sensing
Authors: Srivastava Deepa , Bhatnagar Randhir , Kumar Asha , Parmar Vinod
Published: September 2014

We demonstrate a prominent technique using intensity variation owing to a change in temperature of fiber Bragg grating (FBG) instead of just a shift of Bragg wavelength due to ambient temperature variation. The rising and falling region of chirped fiber Bragg grating (CFBG) spectrum can be used as edge filter, where intensity variation can be observed with the shift in wavelength due to change in temperature. The proposed hypothesis of intensity variation with a shift in wavelength at rising edge of CFBG has been investigated theoretically and later on these results are verified experimentally. The rising and falling edge of CFBG are analyzed and then FBG was written on 1542.4 nm. The rising edge of CFBG have linear region in the range of 1542.3–1542.7 nm wavelength. Thus intensity will be modulated linearly with a shift of Bragg wavelength in this region. In‐house fabricated FBG has been used and CFBG as an edge filter was implemented in our experiment to verify the proposed concept of intensity modulation. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2913–2915, 2014
Characterization of a compartment syndrome–like injury model
Authors: Oyster Nick , Witt Michelle , Gharaibeh Burhan , Poddar Minakshi , Schneppendahl Johannes , Huard Johnny
Published: September 2014

Introduction: Acute compartment syndrome (CS) is caused by an elevation of pressure within a muscular compartment that can be caused by numerous factors, including blunt trauma. In this study, we characterized a rodent model of CS‐like injury. Methods: Forty male athymic rats received a standardized injury of ischemia and compression to their hindlimbs, while the intracompartmental pressure (ICP) was measured using an implantable transmitter. Tetanic muscle function was evaluated, and histology was performed on the tibialis anterior (TA) muscle. Results: ICPs were held at 260.70 ± 2.70 mm Hg during injury. Injured muscles recovered 59% of their total function 4 weeks after injury, and histology showed high levels of edema, inflammation (CD68+), angiogenesis (CD31+), and fibrosis within 72 hours after injury. Conclusions: We describe a novel CS‐like injury model and a novel method to measure ICP, which could potentially be used to develop innovative therapies to manage CS injury in patients. Muscle Nerve 51:750–758, 2015
Multifunctional Benzothiadiazole‐Based Small Molecules Displaying Solvatochromism and Sensing Properties toward Nitroarenes, Anions, and Cations
Authors: Alfonso María , Espinosa Arturo , Tárraga Alberto , Molina Pedro
Published: September 2014

Aryl or heteroaryl 5‐substituted imidazo‐benzothiadiazole derivatives were synthesized and shown to display remarkable solvatofluorochromism and selectively sense mercury(II) cations, acetate anions, and nitroaromatic derivatives, with discrimination betweenp‐nitrophenol and picric acid. These novel sensors are of importance these days, as the detection of explosives is a high priority in issues of national security and environmental protection. To determine the ion binding properties of the sensors, their absorption and fluorescence emission spectra upon binding different cations and anions were compared. Significant shifts in the spectra were only observed for mercury(II) and acetate. The binding of these two ions was further studied using1H NMR. The binding properties of different nitroaromatic compounds were also determined, and the results showed the importance of the presence of a phenol group in the guest molecule. Specifically, the two sensors were shown to discriminate betweenp‐nitrophenol and picric acid. Finally, the mechanism of fluorescence quenching upon addition of nitrophenols was determined by computational methods.
Cu(I) camphor coordination polymers: Synthesis and study of the catalytic activity for cyclization of 4‐pentyn‐1‐oic acid
Authors: Fernandes Tiago A. , Galvão Adelino M. , Botelho do Rego Ana M. , Carvalho M. Fernanda N. N.
Published: September 2014

The number of CuCl units per camphor ligand in [{CuCl}2L]n was extended to three or four in [{CuCl}3L]n (2) or [{CuCl}4L]n (1). The Hartree‐Fock ab initio calculations support the polymeric structure of 1 and 2 that catalyze the cyclization of 4‐pentyn‐1‐oic acid (A) forming 5‐methylenedihydrofuran‐2(3H)‐one (B) and/or 2‐methyl‐5‐oxotetrahydrofuran‐2‐ylpent‐4‐ynoate (C). The catalytic activity of 1, 2 and other polynuclear Cu(I) complexes (3–5) was evaluated under solvent free conditions and/or solution. In the absence of solvent, catalyst 2 displays the highest activity and selectivity (75.8/23.1, C to B ratio, at 5.4% loading) while 4 reaches the highest level of A → B conversion (97.5 %) in solution. Selected reactions were followed by NMR and the kinetic constants calculated. A mechanism is proposed based on the equations used for the calculations. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 3316–3323
One donor–two acceptor (D–A1)‐(D–A2) random terpolymers containing perylene diimide, naphthalene diimide, and carbazole units
Authors: Kozycz Lisa M. , Gao Dong , Tilley Andrew J. , Seferos Dwight S.
Published: September 2014

A series of one donor–two acceptor (D–A1)‐(D–A2) random terpolymers containing a 2,7‐carbazole donor and varying compositions of perylene diimide (PDI) and naphthalene diimide (NDI) acceptors was synthesized via Suzuki coupling polymerization. The optical properties of the terpolymers are weighted sums of the constituent parent copolymers and all show strong absorption over the 400 to 700 nm range with optical bandgaps ranging from 1.77 to 1.87 eV, depending on acceptor composition. The copolymers were tested as acceptor materials in bulk heterojunction all‐polymer solar cells using poly[(4,8‐bis‐(2‐ethylhexyloxy)‐benzo[1,2‐b;4,5‐b′]dithiophene)‐2,6‐diyl‐alt‐(4‐(2‐ethylhexanoyl)‐thieno[3,4‐b]thiophene)‐2,6‐diyl] (PBDTTT‐C) as the donor material. In contrast to the optoelectronic properties, the measured device parameters are not composition dependent, and rather depend solely on the presence of the NDI unit, where the devices containing any amount of NDI perform half as well as those using the parent polymer containing only carbazole and PDI. Overall this is the first example of a one donor–two acceptor random terpolymer system containing perylene diimide (PDI) and naphthalene diimide (NDI) acceptor units, and demonstrates a facile method of tuning polymer optoelectronic properties while minimizing the need for complicated synthetic and purification steps. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 3337–3345
Solution behavior of polyimide‐graft‐polystyrene copolymers in selective solvents
Authors: Filippov Alexander P. , Belyaeva Elena V. , Meleshko Tamara K. , Yakimansky Alexander V.
Published: September 2014

A polyimide‐graft‐polystyrene (PI‐g‐PS) copolymer with a polyimide backbone and polystyrene side chains was synthesized by the “grafting from” method using styrene polymerization on a polyimide multicenter macroinitiator via ATRP mechanism. The side chain grafting density z = 0.86 of PI‐g‐PS is rather high for graft‐copolymers synthesized by the ATRP method. Molecular characteristics and solution behavior of PI‐g‐PS were studied in selective solvents using light scattering and viscometry methods. In all solvents, the backbone tends to avoid contact with a poor solvent. To describe the conformation and hydrodynamic properties of PI‐g‐PS macromolecules in thermodynamically good solvents for side chains and PI‐g‐PS, the wormlike spherocylinder model is used. Macromolecules of the studied graft‐copolymer are characterized by high equilibrium rigidities (Kuhn segment length >20 nm). In Θ‐conditions, PI‐g‐PS macromolecules may be modeled by a rigid prolate ellipsoid of revolution with a low asymmetry form and a collapsed backbone as the ellipsoid core. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 1539–1546
On the number of components in a Gaussian mixture model
Authors: McLachlan Geoffrey J. , Rathnayake Suren
Published: September 2014

Mixture distributions, in particular normal mixtures, are applied to data with two main purposes in mind. One is to provide an appealing semiparametric framework in which to model unknown distributional shapes, as an alternative to, say, the kernel density method. The other is to use the mixture model to provide a probabilistic clustering of the data intogclusters corresponding to thegcomponents in the mixture model. In both situations, there is the question of how many components to include in the normal mixture model. We review various methods that have been proposed to answer this question.WIREs Data Mining Knowl Discov2014, 4:341–355. doi: 10.1002/widm.1135

This article is categorized under:

Technologies > Machine Learning
From micropterism to hyperpterism: recognition strategy and standardized homology-driven terminology of the forewing venation patterns in planthoppers (Hemiptera: Fulgoromorpha)
Authors: Bourgoin Thierry , Wang Rong-Rong , Asche Manfred , Hoch Hannelore , Soulier-Perkins Adeline , Stroiński Adam , Yap Sheryl , Szwedo Jacek
Published: September 2014

Following recent advances in the morphological interpretations of the tegmen basal cell margins in the Paraneoptera, a standardized and homology-driven groundplan terminology for tegmina types, structures and vein patterns in Hemiptera Fulgoromorpha, including fossils, is proposed. Each term is listed with a morphological definition, compared and linked to the main systems of planthopper forewing description that have been reviewed. The importance of a standardized and homology-driven terminology is stressed to enhance the quality of data in taxonomic descriptions and to strengthen phylogenetic morphological analysis results. When the interpretation of the origin of vein branches is render difficult, a three-step strategy for pattern recognition of the vein is proposed based on two principles: (1) vein forks are more informative than topology of the vein branches: a search for homologous areas, the nodal cells in particular, must first guide the recognition rather the number of branches of a vein, and (2) minimum of ad hoc evolutionary events should be invoked in the understanding of a modified vein pattern. Examples of some conflicting interpretations of venation patterns in planthoppers are discussed within different families for both extant and extinct taxa. For the first time, the concept of brachypterism is defined in a non-relative way independently from other structures, and the new one of hyperpterism is proposed; a reporting system is proposed for each of them.
The Detection Rate of Cardiac Anomalies at 11–13+6 Week Scan Using Four Chamber View and Three Vessel View
Authors: Batra Meenu , Gopinathan K. K. , Balakrishnan Bijoy , Gopinath Parasuram , Kuriakose Rekha , Gupta Jyotsna
Published: September 2014

The primary aim of this study was to assess the feasibility of fetal cardiac evaluation at 11–13+6 weeks by assessing the four chamber and three vessel views. The secondary aim was to assess detection rates of cardiac anomalies at this gestational age. This was a prospective study done over 1 year. It included 355 patients who presented to a routine antenatal service and opted for prenatal genetic screening and anomaly scan at 11–13+6 weeks corresponding to a CRL of 45–84 mm. Four chamber view and three vessel view were examined in both gray scale and color Doppler using transabdominal scanning and transvaginal scanning. A follow-up was done at 18–22 weeks and at delivery. Major cardiac anomalies were seen in 5 (1.4 %) fetuses screened at 11–13+6 weeks. Two fetuses with cardiac anomalies (0.5 %) could not be detected at this gestation and were picked up at the 18–22 week scan. Extracardiac anomalies detected in the first trimester scan were 14 (3.9 %). Nuchal translucency (NT) of more than 3 mm was found in 19 (5.3 %) patients. Nuchal translucency of more than 3 mm was present in 3 (60 %) fetuses with cardiac defects seen at 11–13+6 weeks. Increased NT of more than 3 mm was found in 6 (43 %) patients having noncardiac anomalies. Four (1.1 %) patients had both cardiac and noncardiac anomalies detected at first trimester scan. When CRL was 76–85 mm, the cardiac anomaly detection rate was maximum (3.8 %) compared to detection at CRL 66–75 mm (1.2 %), 56–65 mm (0), 45– 55 mm (2.2 %). Noncardiac defects had a detection rate of 2 (4.4 %) at CRL 45–55 mm, 4 (3.6 %) at CRL 56–65 mm, 7 (4.5 %) at CRL 66–75 mm, 1 (1.9 %) at CRL 76–85 mm. Overall detection of major fetal cardiac anomalies at 11–13+6 weeks was 1.4 % and noncardiac anomalies was 3.9 %. This supports the opinion that first trimester can be used for detection of major congenital heart diseases and noncardiac anomalies along with fetal aneuploidy screening. Detection of anomalies in the first trimester helps patient in early decision making and counseling for further management.
On compactness estimates for hyperbolic systems of conservation laws
Authors: Ancona Fabio , Glass Olivier , Nguyen Khai T.
Published: September 2014

We study the compactness in

L_{\mathrm{loc}}^{1}

of the semigroup mapping

(S_{t})_{t > 0}

defining entropy weak solutions of general hyperbolic systems of conservation laws in one space dimension. We establish a lower estimate for the Kolmogorov

ε

-entropy of the image through the mapping

S_{t}

of bounded sets in

L^{1} \cap L^{\infty }

, which is of the same order

1/ \varepsilon

as the ones established by the authors for scalar conservation laws. We also provide an upper estimate of order

1/ \varepsilon

for the Kolmogorov

ε

-entropy of such sets in the case of Temple systems with genuinely nonlinear characteristic families, that extends the same type of estimate derived by De Lellis and Golse for scalar conservation laws with convex flux. As suggested by Lax, these quantitative compactness estimates could provide a measure of the order of “resolution” of the numerical methods implemented for these equations.

Nous étudions la compacité dans

L_{\mathrm{loc}}^{1}

du semi-groupe

(S_{t})_{t > 0}

définissant les solutions faibles d'entropie de systèmes hyperboliques de lois de conservation généraux en dimension un d'espace. Nous établissons une estimée inférieure de l'

ε

-entropie de Kolmogorov de l'image par l'application

S_{t}

d'ensembles bornés dans

L^{1} \cap L^{\infty }

, qui est du même ordre

1/ \varepsilon

que celles establies par les auteurs pour les lois de conservation scalaires. Nous obtenons aussi une estimée supérieure d'ordre

1/ \varepsilon

pour l'

ε

-entropie de Kolmogorov de tels ensembles dans le cas des systèmes de Temple avec des champs charactéristiques vraiment non linéaires, ce qui étend le même type d'estimées obtenues par De Lellis et Golse dans le cas des lois de conservation scalaires à flux convexe. Comme suggéré par Lax, ces estimées quantitatives pourraient donner une mesure de l'ordre de « résolution » de méthodes numériques mises en place pour ces équations.
Cyclin D1 acts as a barrier to pluripotent reprogramming by promoting neural progenitor fate commitment
Authors: Chen Chih-Lung , Wang Liang-Jie , Yan Yu-Ting , Hsu Hung-Wei , Su Hong-Lin , Chang Fang-Pei , Hsieh Patrick C.H. , Hwang Shiaw-Min , Shen Chia-Ning
Published: September 2014

A short G1 phase is a characteristic feature of the cell cycle structure of pluripotent cells, and is reestablished during Yamanaka factor‐mediated pluripotent reprogramming. How cell cycle control is adjusted to meet the requirements of pluripotent cell fate commitment during reprogramming is less well understood. Elevated levels of cyclin D1 were initially found to impair pluripotency maintenance. The current work further identified Cyclin D1 to be capable of transcriptionally upregulating Pax6, which promoted reprogramming cells to commit to a neural progenitor fate rather than a pluripotent cell fate. These findings explain the importance of reestablishment of G1‐phase restriction in pluripotent reprogramming.
Recurrence of atrial fibrillation within three months after pulmonary vein isolation for patients with paroxysmal atrial fibrillation: Analysis using external loop recorder with auto‐trigger function
Authors: Kawasaki Shiro , Tanno Kaoru , Ochi Akinori , Inokuchi Koichiro , Chiba Yuta , Onishi Yoshimi , Onuma Yoshimasa , Munetsugu Yumi , Kikuchi Miwa , Ito Hiroyuki , Onuki Tatsuya , Miyoshi Fumito , Minoura Yoshino , Watanabe Norikazu , Adachi Taro , Asano Taku , Kobayashi Youichi
Published: September 2014

Background

Pulmonary vein isolation (PVI) via catheter ablation has been shown to be a highly effective treatment option for patients with symptomatic paroxysmal atrial fibrillation (AF). The recurrence of AF within 3 months after PVI is not considered to be the result of ablation procedure failure, because early recurrence of AF is not always associated with late recurrence. We examined the usefulness of an external loop recorder with an auto‐trigger function (ELR‐AUTO) for the detection of atrial fibrillation following PVI to characterize early recurrence and to determine the implications of AF occurrence within 3 months after PVI.

Methods

Fifty‐three consecutive symptomatic patients with paroxysmal AF (age 61.6±12.6 years, 77% male) who underwent PVI and were fitted with ELR‐AUTO for 7±2.0 days within 3 months after PVI were enrolled in this study.

Results

Of the 33 (62.2%) patients who did not have AF recurrence within 3 months after PVI, only 1 patient experienced AF recurrence at 12 months. Seven (35%) of the 20 patients who experienced AF within 3 months of PVI experienced symptomatic AF recurrence at 12 months. The sensitivity, specificity, positive predictive value, and negative predictive value of early AF recurrence for late recurrence were 87.5%, 71.1%, 35.0%, and 96.9%, respectively.

Conclusions

AF recurrence measured by ELR‐AUTO within 3 months after PVI can predict the late recurrence of AF. Freedom from AF in the first 3 months following ablation significantly predicts long‐term AF freedom. ELR‐AUTO is useful for the detection of symptomatic and asymptomatic AF.
Spatial and temporal variability of the complex fractionated atrial electrogram activity and dominant frequency in human atrial fibrillation
Authors: Kogawa Rikitake , Okumura Yasuo , Watanabe Ichiro , Kofune Masayoshi , Nagashima Koichi , Mano Hiroaki , Sonoda Kazumasa , Sasaki Naoko , Ohkubo Kimie , Nakai Toshiko , Hirayama Atsushi
Published: September 2014

Background

The presence of complex fractionated atrial electrograms (CFAEs) and high dominant frequencies (DFs) during atrial fibrillation (AF) have been demonstrated to be related to AF maintenance. Therefore, sequential mapping of CFAEs and DFs have been used for target sites of AF ablation. However, such mapping strategies are valid only if the CFAEs and DFs are spatiotemporally stable during the mapping procedure. We obtained spatially stable multi‐electrode recordings to assess the spatiotemporal stability of CFAEs and DFs.

Methods

We recorded electrical activity during AF for 10 min with a 64‐electrode basket catheter (48 bipole electrode pairs) placed in the left atrium in 36 patients with AF (paroxysmal AF [PAF], n=16; persistent AF [PerAF], n=20). The spatial and temporal distribution of the CFAEs (fractionation interval <120 ms) and high DFs (>8 Hz) at 1‐min intervals for 10 min were compared for each of the 48 bipoles.

Results

The baseline CFAEs were located at 68.5±14.0% (32.9±6.7) of the 48 bipoles; however, the high DF sites were fewer (9.6±8.6% [4.6±4.1 bipoles]). The CFAEs sites did not change significantly during the 10‐min recording period (kappa statistic: 0.71±0.24); however, the high DF sites changed significantly (kappa statistic: 0.07±0.19). These spatiotemporal changes in the CFAEs and high DFs did not differ between patients with PAF and PerAF.

Conclusions

Regardless of the AF type, CFAEs sites, but not high DF sites, showed a high degree of spatial and temporal stability.
Small molecule growth inhibitors of human oncogenic gammaherpesvirus infected B‐cells
Authors: Dzeng Richard K. , Jha Hem Chandra , Lu Jie , Saha Abhik , Banerjee Sagarika , Robertson Erle S.
Published: September 2014

Epstein–Barr virus (EBV) and Kaposi's sarcoma‐associated herpesvirus (KSHV) are two human gammaherpesviruses associated with a broad spectrum of B‐cell lymphomas, most acutely in immuno‐compromised populations. However, there are no drugs which specifically target KSHV or EBV‐associated lymphomas. To identify small molecules which selectively inhibit the growth of EBV or KSHV‐associated B‐cell lines, we performed a fluorescence based high‐throughput screen on multiple stable GFP expressing virus‐infected or uninfected B‐cell lines. We identified 40 initial compounds with selective growth inhibition and subsequently determined the 50% growth inhibitory concentrations (GI50) for each drug. We further examined compounds with higher specificity to explore the underlying molecular mechanisms using transcription factor analysis, as well as a shRNA based knockdown strategy. Our data identified ten compounds with relatively high efficacy for growth inhibition. Two novel small molecules, NSC#10010 and NSC#65381 were potent growth inhibitors for gammaherpesvirus‐associated B‐lymphomas through activation of both the NF‐κB and c‐Myc‐mediated signaling pathways. These drugs can serve as potential lead compounds to expand the current therapeutic window against EBV or KSHV‐associated human B‐cell malignancies.
Upper Limb Strength: Study Providing Normative Data for a Clinical Handheld Dynamometer
Authors: Van Harlinger Wanda , Blalock Lori , Merritt John L.
Published: September 2014

Objective

To establish normative clinical data for upper extremity strength of men and women, ages 20‐64 years, using a portable clinical device, the Nicholas Manual Muscle Tester (NMMT).

Design

The study collected objective upper extremity strength data for 180 healthy men and women using the NMMT.

Setting

The study was conducted in outpatient and community settings.

Subjects

One hundred eighty normal volunteers (90 men and 90 women).

Methods

Eleven upper extremity muscle groups were tested using standardized methodology.

Main Outcome Measurements

Data were recorded for each muscle group in each subject.

Results

This study presents data from 180 healthy, normal subjects, equally divided by gender and age. Means ± standard deviations were determined for each group and further categorized by age, gender, and hand dominance. These data confirm some expected patterns: In all the muscle groups men have significantly higher strength than women, and the dominant side is stronger than the nondominant side in men and women. Relative values for various muscle groups are analyzed and presented.

Conclusions

This study provides an initial normative database across a wide age range in men and women for upper extremity strength for monitoring clinical care and research for injured and impaired patients. These data are an essential and initial step toward comprehensive normative databases for upper extremity objective ordinal strength measurements with the NMMT.
Surface Electromyography of Wrist Flexors and Extensors in Children With Hemiplegic Cerebral Palsy
Authors: Xu Kaishou , Mai Jianning , He Lu , Yan Xiaohua , Chen Ying
Published: September 2014

Objective

To investigate the characteristics of motor unit recruitment and coordination function of the wrist during maximum isometric voluntary contraction (MIVC) using surface electromyography (EMG) in children with hemiplegic cerebral palsy (CP).

Design

A cross‐sectional trial.

Setting

Hospital neurology and rehabilitation department.

Participants

Sixty‐eight children with spastic hemiplegic CP.

Methods

The signals of wrist flexors and extensors in unaffected and affected hands of children with hemiplegic cerebral palsy were measured with surface EMG. The characteristics of integrated EMG (iEMG), root mean square (RMS), and co‐contraction ratio of surface EMG were analyzed.

Results

The RMS and iEMG in the affected hand during MIVC were higher than that of the unaffected hand (P < .001). The RMS and iEMG of wrist extensors and the iEMG of wrist flexors of the affected hand had a good correlation with the unaffected hand (P < .01). The RMS and iEMG of the unaffected hand during MIVC were higher than that of the affected hand (P < .001), and the iEMG of the unaffected hand had a good correlation with the affected hand (P < .05). The RMS and iEMG in the unaffected hand during MIVC were significantly higher than that of the affected hand during MIVC (P < .001). The co‐contraction ratio of the unaffected hand was significantly lower than that of the affected hand (P < .001).

Conclusions

The affected side shows more co‐contractions than the unaffected side in children with hemiplegic CP. However, the unaffected side demonstrates stronger motor unit recruitment at maximal effort than the affected side. In addition, this study demonstrates the successful use of surface EMG for assessment of motor unit activation in young children with CP.