bluuebunny/crossref_metadata_2025 huggingface dataset:
Organische Chemie 2010
Authors: Bräse Stefan
Published: March 2011

Stefan Bräse (Koordinator) et al.

Die Highlights des Jahres: Funktionswerkstoffe für Solarzellen — Funktionalisierte Graphenbausteine — Kupfer in Kreuzkupplungen — Nobelpreis für Palladium‐Chemie — Palau'amin — AAT‐Bausteine für die Zuckerchemie.
Theoretische Chemie 2010
Authors: Auer Alexander , Kästner Johannes , Burghardt Irene
Published: March 2011

Tensorzerlegungen haben ein enormes Potenzial für effizientere Näherungen in der Quantenchemie. Bei QM/MM‐Ansätzen liegen heute die Herausforderungen darin, die vielen Freiheitsgrade realistisch zu behandeln. In der Quantendynamik werden angesichts der wachsenden Komplexität der untersuchten Systeme universell anwendbare Verfahren seltener.
Makromolekulare Chemie 2010
Authors: Luxenhofer Robert , Groll Jürgen , Schnieders Frank , Oenbrink Georg
Published: March 2011

Makromoleküle lassen sich mit orthogonalen chemischen Reaktionen maßschneidern. Teilweise biologisch inspirierte Konzepte kombinieren Selbstanordnung mit Funktionalität. Hauptanwendungsgebiete funktionaler Makromoleküle sind Elektronik und Biomedizin.
Chemiedidaktik 2010
Authors: Becker Hans‐Jürgen , Hildebrandt Henry
Published: March 2011

Die Wirtschaft stellt für die Förderung chemischer Bildungsprozesse derzeit enorme Ressourcen bereit. Eine chemiedidaktische Perspektive entwickelt sich erst allmählich, sie muss und kann an vorliegende Forschungen zum Verhältnis von Chemieunterricht und Wirtschaft anknüpfen.
Rechtssicherheit im Labor — Wer haftet beim Unfall?
Authors: Maas Nicole , Brombach Matthias
Published: March 2011

Wie kann ein Laborleiter verhindern, dass er sich strafbar macht und ihn die Berufsgenossenschaft in Regress nimmt, wenn sich ein Mitarbeiter im Labor verletzt?
An automated database case definition for serious bleeding related to oral anticoagulant use
Authors: Cunningham Andrew , Stein C. Michael , Chung Cecilia P. , Daugherty James R. , Smalley Walter E. , Ray Wayne A.
Published: March 2011

Purpose

Bleeding complications are a serious adverse effect of medications that prevent abnormal blood clotting. To facilitate epidemiologic investigations of bleeding complications, we developed and validated an automated database case definition for bleeding‐related hospitalizations.

Methods

The case definition utilized information from an in‐progress retrospective cohort study of warfarin‐related bleeding in Tennessee Medicaid enrollees 30 years of age or older. It identified inpatient stays during the study period of January 1990 to December 2005 with diagnoses and/or procedures that indicated a current episode of bleeding. The definition was validated by medical record review for a sample of 236 hospitalizations.

Results

We reviewed 186 hospitalizations that had medical records with sufficient information for adjudication. Of these, 165 (89%, 95%CI: 83–92%) were clinically confirmed bleeding‐related hospitalizations. An additional 19 hospitalizations (10%, 7–15%) were adjudicated as possibly bleeding‐related. Of the 165 clinically confirmed bleeding‐related hospitalizations, the automated database and clinical definitions had concordant anatomical sites (gastrointestinal, cerebral, genitourinary, other) for 163 (99%, 96–100%). For those hospitalizations with sufficient information to distinguish between upper/lower gastrointestinal bleeding, the concordance was 89% (76–96%) for upper gastrointestinal sites and 91% (77–97%) for lower gastrointestinal sites.

Conclusion

A case definition for bleeding‐related hospitalizations suitable for automated databases had a positive predictive value of between 89% and 99% and could distinguish specific bleeding sites. Copyright © 2011 John Wiley & Sons, Ltd.
iTRAQ‐based proteomic study of the effects of microcystin‐LR on medaka fish liver
Authors: Malécot Mélodie , Marie Arul , Puiseux‐Dao Simone , Edery Marc
Published: March 2011

Microcystins are cyanotoxins that occur in ground water and thus pose a potential health risk. Microcystin‐LR (microcystin‐leucine‐arginine) is a potent hepatotoxin, and is suspected of being a tumour promoter. Poisoning with this toxin causes several dysfunctions in hepatocytes by inhibiting protein phosphatases 1 and 2A, and notably produces oxidative stress, disrupts the cytoskeleton, and deregulates mitogen‐activated protein kinase pathway. Medaka fish (Oryzias latipes) was chosen as a model for studying the effects of this cyanotoxin on liver proteins using a gel‐free approach, iTRAQ. Fish were gavaged with microcystin‐LR. Two hours later, 325 proteins could be identified by Scaffold Q+ and 32 proteins revealed statistically significant variations above a ∣0.2∣ threshold of log2 ratio by comparison with control. These proteins are mostly involved in the translation and maturation of proteins, lipid metabolism and detoxification. Notably, apolipoproteins are deregulated which indicates a possible alteration of chylomicron‐mediated transport.
Investigating the plant response to cadmium exposure by proteomic and metabolomic approaches
Authors: Villiers Florent , Ducruix Céline , Hugouvieux Véronique , Jarno Nolwenn , Ezan Eric , Garin Jérôme , Junot Christophe , Bourguignon Jacques
Published: March 2011

Monitoring molecular dynamics of an organism upon stress is probably the best approach to decipher physiological mechanisms involved in the stress response. Quantitative analysis of proteins and metabolites is able to provide accurate information about molecular changes allowing the establishment of a range of more or less specific mechanisms, leading to the identification of major players in the considered pathways. Such tools have been successfully used to analyze the plant response to cadmium (Cd), a major pollutant capable of causing severe health issues as it accumulates in the food chain. We present a summary of proteomics and metabolomics works that contributed to a better understanding of the molecular aspects involved in the plant response to Cd. This work allowed us to provide a finer picture of general signaling, regulatory and metabolic pathways that appeared to be affected upon Cd stress. In particular, we conclude on the advantage of employing different approaches of global proteome‐ and metabolome‐wide techniques, combined with more targeted analysis to answer molecular questions and unravel biological networks. Finally, we propose possible directions and methodologies for future prospectives in this field, as many aspects of the plant–Cd interaction remain to be discovered.
Analysis of the xylem sap proteome of Brassica oleracea reveals a high content in secreted proteins
Authors: Ligat Laetitia , Lauber Emmanuelle , Albenne Cécile , Clemente Hélène San , Valot Benoît , Zivy Michel , Pont‐Lezica Rafael , Arlat Matthieu , Jamet Elisabeth
Published: March 2011

Xylem plays a major role in plant development and is considered part of the apoplast. Here, we studied the proteome of Brassica oleracea cv Bartolo and compared it to the plant cell wall proteome of another Brassicaceae, the model plant Arabidopsis thaliana. B. oleracea was chosen because it is technically difficult to harvest enough A. thaliana xylem sap for proteomic analysis. We studied the whole proteome and an N‐glycoproteome obtained after Concanavalin A affinity chromatography. Altogether, 189 proteins were identified by LC‐MS/MS using Brassica EST and cDNA sequences. A predicted signal peptide was found in 164 proteins suggesting that most proteins of the xylem sap are secreted. Eighty‐one proteins were identified in the N‐glycoproteome, with 25 of them specific of this fraction, suggesting that they were concentrated during the chromatography step. All the protein families identified in this study were found in the cell wall proteomes. However, proteases and oxido‐reductases were more numerous in the xylem sap proteome, whereas enzyme inhibitors were rare. The origin of xylem sap proteins is discussed. All the experimental data including the MS/MS data were made available in the WallProtDB cell wall proteomic database.
Survivor profiles predict health behavior intent: the Childhood Cancer Survivor Study
Authors: Cox Cheryl L. , Zhu Liang , Finnegan Lorna , Steen Brenda D. , Hudson Melissa M. , Robison Leslie L. , Oeffinger Kevin C.
Published: March 2011

Objectives: To determine whether unique groups of adult childhood cancer survivors could be defined on the basis of modifiable cognitive, affective, and motivation indicators. Secondary objectives were to examine to what extent group membership co‐varied with more static variables (e.g. demographics, disease, and treatment) and predicted intent for subsequent medical follow‐up.

Methods: Using latent class analysis of data from 978 participants (ages, 18–52 years; mean, 31; and SD, 8) in the Childhood Cancer Survivor Study, we classified survivors according to their worries about health, perceived need for follow‐up care, health motivation, and background variables. Intent to participate in medical follow‐up, as a function of class membership, was tested using equality of proportions.

Results: The best‐fitting model (BIC = 18 540.67, BLMRT = <0.001) was characterized by three distinctive survivor classes (worried, 19%; self‐controlling, 26%; and collaborative, 55%) and three significant class covariates (gender, perceptions of health, and severity of late effects). A smaller proportion of survivors in the self‐controlling group (81%) than in the worried (90%) (P = 0.015) and collaborative (88%) (P = 0.015) groups intended to obtain a routine medical checkup. A smaller proportion of survivors in the self‐controlling group (32%) than in the collaborative (65%) (P = <0.001) and worried (86%) (P = <0.001) groups planned a cancer‐related check‐up. A smaller proportion of survivors in the collaborative group (65%) than in the worried group (86%) (P = <0.001) were likely to obtain a cancer‐related check‐up.

Conclusions: Childhood cancer survivors can be classified according to the modifiable indicators. The classification is distinctive, predicts intent for future medical follow‐up, and can inform tailored interventions. Copyright © 2011 John Wiley & Sons, Ltd.
Does screening for distress efficiently uncover meetable unmet needs in cancer patients?
Authors: van Scheppingen Corinne , Schroevers Maya J. , Smink Ans , van der Linden Yvette M. , Mul Véronique E. , Langendijk Johannes A. , Coyne James C. , Sanderman Robbert
Published: March 2011

Objectives: We evaluated screening for distress in terms of its ability to uncover unmet need for psychosocial services in cancer patients. Correlates of distress, need for services and met and unmet need for services were investigated.

Methods: Immediately after cancer treatment (T1) and 2 months later (T2), 302 patients completed the Hopkins Symptom Checklist‐25 (HSCL‐25) and a single question assessing the need for services. All distressed patients (HSCL‐25⩾39) and non‐distressed patients endorsing a need for services were then called (n = 99) to assess their need.

Results: Thirty‐seven percent (T1) and 31% (T2) of patients were distressed and 31% (T1) and 18% (T2) expressed the need for services. Both time points showed higher distress in younger patients and females and lower distress in prostate cancer and patients treated by radiotherapy only. Less need for services was found in prostate cancer (T1), greater need was related to being single (T1) and younger (T2). Distress and need for services were positively related (p<0.001). The HSCL‐25 showed modest sensitivity (T1: 0.59, T2: 0.65) and specificity (T1: 0.75, T2: 0.78) as an indicator of need for services. Interviews at T2 revealed that 51% of distressed patients needed no psychosocial services and 25% were already receiving services. At T2, regardless of distress level, 10% of all screened patients reported an unmet need for psychosocial services.

Conclusions: Depending on the clinical context, screening might be more efficient if it assessed the unmet need for services rather than distress. More attention should be concentrated on directing patients with meetable unmet needs to available services. Copyright © 2011 John Wiley & Sons, Ltd.
Anxiety, depression, and life satisfaction in parents caring for children with cystic fibrosis
Authors: Besier Tanja , Born Anja , Henrich Gerhard , Hinz Andreas , Quittner Alexandra L. , Goldbeck Lutz ,   The TIDES Study Group
Published: March 2011

Objective

To assess the prevalence of symptoms of anxiety and depression and the extent of life satisfaction in parents caring for children with cystic fibrosis (CF) in Germany.

Methods

The study included 650 caregivers of 564 children with CF ages 0–17, who completed the Hospital Anxiety Depression Scale (HADS), the Center for Epidemiologic Studies Depression Scale (CES‐D) and the Questions on Life Satisfaction (FLZM).

Results

More than one‐third (37.2%) of parents showed elevated levels of anxious symptoms, compared to 18.9% of a population sample (P ≤ 0.001) and significantly more parents reported elevated levels of depressive symptoms compared to a community sample (28% vs. 21%, P = 0.01). Higher levels of anxious and depressive symptoms were associated with lower life satisfaction (P < 0.001).

Conclusions

High levels of anxious and depressive symptoms among parents of children with CF suggested that annual symptom screening is warranted. This will facilitate identification of those at risk and provide referrals and intervention for those who are in need of it. Pediatr. Pulmonol. 2011; 46:672–682. © 2011 Wiley‐Liss, Inc.
Soft magnetic multilayer films with wide frequency band losses and high resistivity
Authors: Ma Qiang
Published: March 2011

A series of CoFeB/MgO multilayers was fabricated by means of DC/RF magnetron sputtering. It is observed that the electromagnetic properties of the multilayers of CoFeB/MgO are closely related with the thickness of CoFeB sublayers, and the soft magnetic properties of discontinuous multilayers are affected by the cycle number of CoFeB/MgO bilayers. The optimized film of [Co64Fe24B12(0.7 nm)/MgO(0.4 nm)]50 exhibits a magnetic loss µ″ larger than 100 and µ′ larger than 80 between 0.9 and 2.1 GHz. The electrical resistivity ρ of this film is as high as 3.75 × 103 µΩ cm. The results indicate that this discontinuous CoFeB/MgO multilayer film has potential to serve as a noise suppressor or EMC materials in the GHz frequency range.
Growth temperature dependence of the electrical and structural properties of epitaxial graphene on SiC(0001)
Authors: Vesapuisto E. , Kim W. , Novikov S. , Lipsanen H. , Kuivalainen P.
Published: March 2011

Epitaxial graphene thin films were grown in an argon atmosphere by silicon sublimation from the (0001) faces of 4H‐SiC in a temperature range T = 1520–1710 °C. Surface morphology, structure and the electrical properties of the layers were studied using atomic force microscopy (AFM), Auger electron spectroscopy (AES), and the measurements of Hall effect mobilities and sheet carrier densities. We further improved the computational model for the analysis of the AES in the determination of the number of graphene layers on SiC. A narrow temperature window T = 1620–1650 °C was found that clearly maximizes the Hall effect mobility up to 400 cm2/Vs in the cases where also a graphene monolayer is formed. The rather low values of the Hall effect mobilities are explained using a barrier model where regions having low resistivity are separated by higher resistivity barrier regions related to the observed grain boundaries in the graphene films.
Synoptic analysis of the Pacific–North American teleconnection pattern
Authors: Franzke Christian , Feldstein Steven B. , Lee Sukyoung
Published: March 2011

In this study, we use various diagnostic techniques to investigate the synoptic evolution of the Pacific–North American teleconnection pattern (PNA). National Center for Environment Prediction/National Center for Atmospheric Research reanalysis data are used. These data cover the years 1948–2008 for the months of November–March. It is found that the positive PNA is initiated by enhanced convection over the western tropical Pacific and weakened convection over the tropical Indian Ocean. The excitation of the negative PNA exhibits opposite features. For both phases, the response to tropical convection excites a small‐amplitude PNA about 8–12 days prior to the pattern attaining its maximum amplitude. This is followed by slow, steady growth for about 5 days, after which driving by synoptic scale waves, via their eddy vorticity flux, together with stationary eddy advection lead to much more rapid growth and the establishment of the full PNA. For the positive PNA, the synoptic scale waves propagate eastward into the midlatitude northeastern Pacific, where they are observed to undergo cyclonic wave breaking. For the negative PNA, the synoptic scale waves first amplify over the midlatitude northeastern Pacific and then propagate equatorward into the Subtropics where they undergo anticyclonic wave breaking. Once established, for both phases, the PNA appears to be maintained through a positive feedback that involves a succession of wave breakings.

These results suggest that preconditioning may play an important role in the formation of the PNA. For the positive PNA, in its early development, the strengthening and eastward extension of the subtropical jet result in an increase in the cyclonic shear and a decrease in the meridional potential vorticity gradient, features that are known to favour cyclonic wave breaking. For the negative PNA, opposite changes were observed for the background flow, which favour equatorward wave propagation and anticyclonic wave breaking. The role of optimal growth is also discussed. Our results also suggest that the PNA is potentially predictable 1–2 weeks in advance. Copyright © 2011 Royal Meteorological Society
Short‐wave and long‐wave radiative properties of Saharan dust aerosol
Authors: Osborne S. R. , Baran A. J. , Johnson B. T. , Haywood J. M. , Hesse E. , Newman S.
Published: March 2011

The radiative properties of mineral dust aerosol during the GERB Intercomparison of Long‐wave and Short‐wave (GERBILS) are presented. GERBILS consisted of aircraft flights over land areas between Mauritania and Niger during June 2007. During one case of large aerosol optical depth (AOD=1.0 at 0.55μm), a short‐wave spectrometer measured sky radiances versus scattering angle that are compared to modelled data. The modelling used phase functions of spheres, spheroids and irregular‐shaped particles using T‐matrix and ray‐tracing methods. Irregular particles provided the most satisfactory solution. In another case of full short‐wave and long‐wave radiative closure, measurements and modelled clear sky conditions allowed calculation of the direct radiative effect (DRE) at high and low level. The modelled AOD (0.92) required to simulate the measured spectral irradiances agrees with the aircraft AOD (0.79) within measurement uncertainty. The simulated irradiances are less sensitive to particle shape than radiances. However, it is shown through modelling of the surface and top‐of‐atmosphere (TOA) DRE over all daylight hours that significant differences exist at TOA due to variation in the asymmetry parameter. The TOA short‐wave diurnally averaged DRE was modelled as between 0 and –20 W m−2 depending on particle shape. A long‐wave interferometer measured downwelling and upwelling radiances to derive surface emissivity across the window region. Measured nadir brightness temperatures from high level show signature of dust. A drop in brightness temperature of 14K was determined using modelled pristine‐sky spectra. The modelled outgoing long‐wave DRE due to dust from this case was +14 W m−2 averaged over 24 h, or +17 W m−2 per unit AOD. Modelling studies illustrate the sensitivity to aerosol refractive index and size distribution for both short‐wave and long‐wave DREs. Considering the full spectrum, a refractive index dataset from the literature has been selected that best represents the Saharan dust encountered during GERBILS. Copyright © 2011 Royal Meteorological Society and British Crown Copyright, the Met Office
Downscaling projections of Indian monsoon rainfall using a non‐homogeneous hidden Markov model
Authors: Greene Arthur M. , Robertson Andrew W. , Smyth Padhraic , Triglia Scott
Published: March 2011

Downscaled rainfall projections for the Indian summer monsoon are generated using a non‐homogeneous hidden Markov model (NHMM) and information from both a dense observational dataset and an ensemble of general circulation models (GCMs). The projections are conditioned on two types of GCM information, corresponding approximately to dynamic and thermodynamic components of precipitation change. These have opposing effects, with a weakening circulation compensating not quite half of the regional precipitation increase that might otherwise be expected. GCM information is taken at the largest spatial scales consistent with regional physics and modelling constraints, while the NHMM produces a disaggregation consistent with the observed fine‐scale spatiotemporal variability. Projections are generated using multimodel mean predictors, with intermodel dispersion providing a measure of the uncertainty due to GCM differences. The downscaled simulations exhibit small increases in the number of dry days, in the average length of dry spells, in mean daily intensity and in the exceedance frequency of nearly all daily rainfall percentiles. Copyright © 2011 Royal Meteorological Society
Investigation of ethynylpyridines using the electron propagator theory
Authors: Singh Raman K. , Mishra Manoj K.
Published: March 2011

The optimized geometry, dipole moment, and HOMO–LUMO gap for three monoethynylpyridines and six diethynylpyridines have been computed using DFT/B3LYP/6‐311++g(3df,3p) level of theory, and the first 11 vertical ionization energies and electron affinity of these compounds have been calculated using various electron propagator decouplings. The outer valence Green's function approximant of the electron propagator theory offers closest agreement with experimental photoelectron spectrum, and the results for structural suitability, dipole moment, HOMO–LUMO gap, ionization energies, and electron affinity indicate that 2‐ethynylpyridine among monoethynylpyridines and 2,6‐diethynylpyridine among diethynylpyridines may be useful precursors for the preparation of conducting polymers. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 112:426–439, 2012
The vibrational spectra of the boron halides and their molecular complexes. Part 13. Ab initio studies of the complexes of boron trifluoride with formaldehyde and some of its analogs
Authors: Ford Thomas A.
Published: March 2011

The structure, the interaction energy, and the vibrational spectrum of the electron donor–acceptor complex formed between boron trifluoride, as a Lewis acid, and formaldehyde, as a Lewis base, have been determined by means of ab initio calculations at the second‐order level of Møller–Plesset perturbation theory, using a triple‐zeta basis set with polarization and diffuse functions on all atoms. The object was to examine the differences in the properties of the complexes formed between boron trifluoride and an oxygen base containing oxygen in the sp2 hybrid state with those of some sp3 oxygen bases studied earlier. The investigation has then been extended to include the related bases thioformaldehyde and methanimine, to assess the effect of substituting the oxygen atom by a sulphur atom or an imino group. A further range of formaldehyde analogs, containing one and two methyl groups, one and two fluorine atoms, and one methyl group and one fluorine atom, has also been included. The preferred structure of each complex has been identified. The computed data have been compared, and the complex properties correlated with some relevant physical properties of the bases. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Interpretation of the hydrogen anomaly in neutron and electron compton scattering
Authors: Karlsson Erik B.
Published: March 2011

In Compton scattering with neutrons in the energy range 20–120 eV, it has been observed that the relative H/M cross sections in a variety of H‐containing materials are 20–40% lower than expected from the composition ratio H/M (M being a heavier element in the same compound). The same phenomenon has also been observed in Compton scattering with electrons of 2 and 20 keV energy. There is, at present, no consensus about the reason for these anomalies. In this theory, they are explained as a result of interference when the scattering particle interacts with more than one hydrogen nucleus. The coherence volume of the actual setup, which limits the number of interfering particles, is therefore an important parameter. It is shown here that the large zero‐point motion of the hydrogen nuclei leads to reductions in the scattering intensity from interfering pairs. Coherence is preserved over the sub‐fs scattering times relevant for this process, even in the condensed systems studied. It is gradually lost when the scattering time is increased, which happens when the neutron energy is reduced (as reflected in lower anomalies for smaller scattering angles). Explicit expressions for the decoherence effect are presented and compared with experimental observation for a selection of observed H‐ and D‐containing systems. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
MRCI study on spectroscopic parameters and molecular constants of the ground state of AsP(X1Σ+) molecule
Authors: Liu Yu‐Fang , Jia Yi , Shi De‐Heng , Sun Jin‐Feng
Published: March 2011

The potential energy curve (PEC) for the ground state of AsP(X1Σ+) has been investigated by the highly accurate valence internally contracted multireference configuration interaction method in the Molpro2008 program package with the correlation consistent basis set. The PEC is fitted to the analytic Murrrell–Sorbie function (M–S function) from which the spectroscopic constants are determined. The present De, Be, αe, ωeχe, Re, and ωe values are of 4.2823 eV, 0.188622 cm−1, 0.000749 cm−1, 1.984427 cm−1, 2.0194 Å, and 598.60 cm−1, respectively. In addition, by numerically solving the radial Schrödinger equation of nuclear motion in the adiabatic approximation, the total of 96 vibration states is predicted when the rotational quantum number J = 0. The complete vibration levels, classical turning points, inertial rotation, and centrifugal distortion constants are reproduced. Comparison has been made with recent theoretical and experimental data. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Understanding the chiral recognitions between neuraminidases and inhibitors: Studies with DFT, docking, and MD methods
Authors: Yang Zhiwei , Wu Xiaomin , Yang Gang , Zu Yuangang , Zhou Lijun
Published: March 2011

The chiral recognitions between various neuraminidases (NA) and 5‐[(1R,2S)‐1‐(acetylamino)‐2‐ methoxy‐2‐methylpentyl]‐4‐[(1Z)‐1‐propenyl)‐(4S,5R)]‐D‐proline (BL) stereoisomers have been theoretically studied. The zwitterions of BL are responsible for the bioactivities, and electrostatic rather than van der Waals (vdW) contributions play a significant role. With the presence of NA proteins, the orders of relative stabilities of the BL stereoisomers are greatly altered; meanwhile, the ranges are significantly enlarged, ensuring the respective recognitions of the BL9z, BL3z, BL2z, and BL1z stereoisomers by the N1, N2, N9 subtype, and B type NA proteins. It is mainly due to geometric complementarities of the NA active sites with the BL carboxyl and propenyl groups. The recognitions of proteins with chiral ligands are rather targeted, even applicable to N2 and N9 with high structural similarities. Thus, the significance of chirality is addressed for the designs of anti‐influenza drugs, which aids our understanding of chiral recognitions between proteins and ligands. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Insights from years of performance that are shaping injection‐based remediation systems
Authors: Suthersan Suthan , Horst John , Nelson Denice , Schnobrich Matthew
Published: March 2011

Research and field experience from the past 15 years has allowed remediation professionals to purposefully design injection‐based remediation systems with a high potential for success. Industry professionals can now claim a number of achievements that were unthinkable just a few years ago: (1) we have demonstrated that maximum contaminant levels (MCLs) can be achieved for multiple contaminants; (2) we have successfully targeted dense nonaqueous‐phase liquid (DNAPL) source zones; (3) we have expanded our understanding of injection hydraulics to treat large plumes; and (4) we have collected sufficient data on rates of treatment to be more predictive regarding outcomes.

The next decade will continue to evolve the design and execution of these types of systems for application to more complex problems. At this point on the timeline, questions regarding the mechanisms of treatment have largely been addressed, allowing a shift in focus to operational enhancements. Specific operational insights arising from the body of work to date that arguably will continue to shape and influence the design and execution of injection‐based remediation systems include: (1) the fact that delivery does not always equal distribution, (2) treatment optimization requires aquifer tuning, and (3) life‐cycle costs can be reduced with remedy‐optimized investigation.

The number of examples that support these concepts and their ramifications to future technology refinement is already increasing, demonstrating how the refinements that can be made around these areas of focus will enhance our ability to effectively tackle larger and more complicated plumes, and do so with maximum efficiency. © 2011 Wiley Periodicals, Inc.
Innovative use of a pressure‐pulse injection tool to increase transmissivity in a collection trench
Authors: Morris Kevin A.
Published: March 2011

Pressure‐pulse injection tools are widely used in the oil and gas extraction industry to increase well production yields; however, they have been sparingly used in the environmental industry. These injection tools work by applying a pressure pulse to the subsurface that can open subsurface pore throats in unconsolidated material, increasing yields or increasing a radius of influence from a substrate injection. Collection trenches at an industrial site were installed to increase recovery of No. 2 fuel oil in the subsurface and maintain hydraulic control of the contaminant plume. However, after operating for seven years, significant reduction in recovery was observed. Diminished recovery was attributed to biofouling, iron fouling, and/or excessive scaling. A pilot test was conducted in 2009 to determine if a pressure‐pulse injection tool could be used to inject an antifouling agent and rehabilitate two of the site collection trenches. The pilot test was successful in increasing the transmissivity of both trenches, with an order‐of‐magnitude increase in groundwater recovery at Collection Trench 1 and a 50 percent increase in recovery at Collection Trench 2. The trench rehabilitation using the pressure‐pulse injection tool was conducted at two other site collection trenches in 2010 with similar success and is now proposed as part of regular maintenance of the trenches on an as‐needed basis. © 2011 Wiley Periodicals, Inc.
Burden and typing of rotavirus group A in Latin America and the Caribbean: systematic review and meta‐analysis
Authors: Linhares Alexandre C. , Stupka Juan A. , Ciapponi Agustín , Bardach Ariel E. , Glujovsky Demián , Aruj Patricia K. , Mazzoni Agustina , Rodriguez Jefferson A. Buendía , Rearte Analía , Lanzieri Tatiana M. , Ortega‐Barria Eduardo , Colindres Romulo
Published: March 2011

The efficacy of licensed rotavirus vaccines has only been shown against certain rotavirus group A (RV‐A) types. It is critical to understand the burden of rotavirus gastroenteritis (RVGE) and its prevalent types to assess the potential impact of these vaccines in Latin America and the Caribbean (LA&C). We performed a systematic review and meta‐analyses of all the available evidence reported from 1990 to 2009 on the burden of rotavirus disease and strains circulating in LA&C. Eligible studies—185 country‐level reports, 174 951 faecal samples—were selected from MEDLINE, Cochrane Library, EMBASE, LILACS, regional Ministries of Health, PAHO, regional proceedings, doctoral theses, reference lists of included studies and consulting experts. Arc‐sine transformations and DerSimonian–Laird random‐effects model were used for meta‐analyses. The proportion of gastroenteritis cases due to rotavirus was 24.3% (95%CI 22.3–26.4) and the incidence of RVGE was 170 per 1000 children‐years (95%CI 130–210). We estimated a global annual mortality for 22 countries of 88.2 (95%CI 79.3–97.1) deaths per 100 000 under 5 years (47 000 deaths).The most common G type detected was G1 (34.2%), followed by G9 (14.6%), and G2 (14.4%). The most common P types detected were P[8] (56.2%), P[4] (22.1%) and P[1] 5.4%, and the most prevalent P–G type associations were P[8]G1 17.9%, P[4]G2 9.1% and P[8]G9 8.8%. In the last 10 years, G9 circulation increased remarkably and G5 almost disappeared. More recently, G12 appeared and P[4]G2 re‐emerged. To our knowledge, this is the first meta‐analysis of rotavirus infection and burden of disease in LA&C. Copyright © 2011 John Wiley & Sons, Ltd.
Smoothing methods for histogram‐valued time series: an application to value‐at‐risk
Authors: Arroyo Javier , González‐Rivera Gloria , Maté Carlos , San Roque Antonio Muñoz
Published: March 2011

We adapt smoothing methods to histogram‐valued time series (HTS) by introducing a barycentric histogram that emulates the “average” operation, which is the key to any smoothing filter. We show that, due to its linear properties, only the Mallows‐barycenter is acceptable if we wish to preserve the essence of any smoothing mechanism. We implement a barycentric exponential smoothing to forecast the HTS of daily histograms of intradaily returns to both the SP500 and the IBEX 35 indexes. We construct a one‐step‐ahead histogram forecast, from which we retrieve a desired γ‐value‐at‐risk (VaR) forecast. In the case of the SP500 index, a barycentric exponential smoothing delivers a better forecast, in the MSE sense, than those derived from vector autoregression models, especially for the 5% VaR. In the case of IBEX35, the forecasts from both methods are equally good. © 2011 Wiley Periodicals, Inc. Statistical Analysis and Data Mining 4: 216–228, 2011
Women using a web‐based digital health coaching programme for stress management: stress sources, symptoms and soping strategies
Authors: Giuseffi Danielle L. , Bedrosian Richard C. , Schwartz Steven M. , Wildenhaus Kevin J. , Wang Chun , Yu Alvin , Wiegand Ben
Published: March 2011

Researchers have proposed and tested many theories to understand gender differences in stress experiences. However, little research has identified differences between subgroups of women in terms of stress sources, symptoms, coping strategies and help‐seeking behaviour. The purpose of this study was to examine these characteristics of women seeking help for stress management through a digital health coaching programme. We examined cross‐sectional data from 63,690 women between the ages of 18 and 59 years who participated in the stress management programme from 2001 to 2008. We divided the sample into age groups to identify developmental patterns in their stress characteristics.

Work, time demands and psychological reactions to stress were consistent concerns, whereas between‐group comparisons indicated diverse stress characteristics by age group. Importantly, women at all ages reported being uncomfortable asking for help. The findings suggest that technology‐based solutions like digital health coaching may reach women who may not otherwise seek or receive help for stress management. The results also emphasize the importance of considering the unique characteristics of women when providing them stress management interventions. Copyright © 2011 John Wiley & Sons, Ltd.
In vivo and in vitro liver and gill EROD activity in rainbow trout (Oncorhynchus mykiss) exposed to the beta‐blocker propranolol
Authors: Bartram Abigail E. , Winter Matthew J. , Huggett Duane B. , McCormack Paul , Constantine Lisa A. , Hetheridge Malcolm J. , Hutchinson Thomas H. , Kinter Lewis B. , Ericson Jon. F. , Sumpter John P. , Owen Stewart F.
Published: March 2011

The conservation of common physiological systems across vertebrate classes suggests the potential for certain pharmaceuticals, which have been detected in surface waters, to produce biological effects in nontarget vertebrates such as fish. However, previous studies assessing the effects of such compounds in fish have not taken into account the potential for metabolism and elimination. This study aimed to assess if propranolol, a β‐adrenergic receptor antagonist or β‐blocker, could modulate EROD activity (indicative of CYP1A activity) in rainbow trout (Oncorhynchus mykiss) gills and liver. For this, an in vivo time course exposure with 1 mg/L was conducted. Additionally, using measured in vivo plasma concentrations, an in vitro exposure at human therapeutic levels was undertaken. This allowed comparison of in vitro and in vivo rates of EROD activity, thus investigating the applicability of cell preparations as surrogates for whole animal enzyme activity analysis. In vitro exposure of suspended liver and gill cells at concentrations similar to in vivo levels resulted in EROD activity in both tissues, but with significantly higher rates (up to six times in vivo levels). These results show that propranolol exposure elevated EROD activity in the liver and gill of rainbow trout, and that this is demonstrable both in vivo (albeit nonsignificantly in the liver) and in vitro, thus supporting the use of the latter as a surrogate of the former. These data also provide an insight into the potential role of the gill as a site of metabolism of pharmaceuticals in trout, suggesting that propranolol (and feasibly other pharmaceuticals) may undergo “first pass” metabolism in this organ. © 2011 Wiley Periodicals, Inc. Environ Toxicol 2012.
Signal pathway of hippocampal apoptosis and cognitive impairment of mice caused by cerium chloride
Authors: Cheng Zhe , Li Na , Cheng Jie , Hu Renping , Gao Guodong , Cui Yaling , Gong Xiaolan , Wang Ling , Hong Fashui
Published: March 2011

Experimental studies have demonstrated that lanthanides could impair cognitive functions of children and animals, but very little is known about the hippocampal apoptosis and its molecular mechanism. The study investigated the signal pathway of hippocampal apoptosis induced by intragastric administration of CeCl3 for 60 consecutive days. It showed that cerium had been significantly accumulated in the mouse hippocampus, and CeCl3 caused hippocampal apoptosis and impairment of spatial recognition memory of mice. CeCl3 effectively activated caspase‐3 and ‐9, inhibited Bcl‐2, and increased the levels of Bax and cytochrome c, promoted accumulation of reactive oxygen species in the mouse hippocampus. It implied that CeCl3‐induced apoptosis in the mouse hippocampus could be triggered via mitochondrion‐mediated pathway. Our findings suggest the need for great caution to handle the lanthanides for workers and consumers. © 2011 Wiley Periodicals, Inc. Environ Toxicol 2012.
Multiple biomarkers responses in juvenile rainbow trout, Oncorhynchus mykiss, after acute exposure to a fungicide propiconazole
Authors: Li Zhi‐Hua , Zlabek Vladimir , Velisek Josef , Grabic Roman , Machova Jana , Kolarova Jitka , Li Ping , Randak Tomas
Published: March 2011

In this study, the toxic effects of propiconazole (PCZ), a triazole fungicide present in aquatic environment, were studied in juvenile rainbow trout, Oncorhynchus mykiss, by acute toxicity test with the concentration of 5.04 mg/L (96 h LC50). Morphological indices, hematological parameters, liver xenobiotic‐metabolizing response, and tissue antioxidant status were evaluated. Compared with the control group, fish exposed to PCZ showed significantly higher Leuko, PCV, MCHC, and hepatic EROD, and significantly lower MCV. CF and HSI were not significantly different among groups. SOD, CAT, GPx, and GR activities increased significantly in liver of experimental groups, but decreased significantly in gill. In general, antioxidant enzyme activity in intestine was less evident than in liver. Oxidative stress indices (levels of LPO and CP) were significantly higher in gill. Additionally, through chemometrics of all parameters measured in this study, two groups with 67.29% of total accumulated variance were distinguished. In short, the physiological and biochemical responses in different tissues of fish indicated that PCZ‐induced the stressful environmental conditions. But according to PCZ residual status in the natural environment, more long‐term experiments at lower concentrations will be necessary in the future. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Support vector machine regularization
Authors: Reeves D. M. , Jacyna G. M.
Published: March 2011

Finding the best decision boundary for a classification problem involves covariance structures, distance measures, and eigenvectors. This article considers how eigenstructures are an inherent part of the support vector machine (SVM) functional basis that encodes the geometric features of a separating hyperplane. SVM learning capacity involves an eigenvector set that spans the parameter space being learned. The linear SVM has been shown to have insufficient learning capacity when the number of training examples exceeds the dimension of the feature space. For this case, an incomplete eigenvector set spans the observation space. SVM architectures based on insufficient eigenstructures lack sufficient learning capacity for good separating hyperplanes. However, proper regularization ensures that two essential types of ‘biases’ are encoded within SVM functional mappings: an appropriate set of algebraic (and thus geometric) relationships and a sufficient eigenstructure set. WIREs Comp Stat 2011 3 204–215 DOI: 10.1002/wics.149

This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Support Vector Machines
Sample size calculations for clinical trials
Authors: Chow Shein‐Chung
Published: March 2011

Sample size calculation plays an important role in clinical research. It is not only to identify signals or trends (with certain statistical assurance) of any (preferably optimal or best) clinical benefits to the patient population under study, but also to ensure that there are sufficient number of subjects enrolled in the study for providing substantial evidence of safety and efficacy of the test treatment under investigation. In practice, there may exist no closed forms for sample size calculations due to the complexity of the intended clinical trials. Different types of clinical trials (e.g., noninferiority/equivalence trials, superiority trials, dose–response trials, and combinational trials) are often conducted for different purposes of clinical investigations under different study designs (e.g., parallel/crossover design, group sequential design, and adaptive clinical trial designs). Thus, different procedures and/or formulas may be employed for achieving study objectives with certain desirable statistical inferences at a prespecified level of significance. This article provides an overview of scientific factors (study endpoint, clinically meaningful difference or treatment effect, controlling type I error rate, etc.) that may have an impact on sample size calculation in clinical research. Some procedures for sample size calculation in nonstandard settings such as sample size adjustment with protocol amendments, two‐stage seamless adaptive trial design with different study objectives and endpoints, and multiregional clinical trials are also discussed. WIREs Comp Stat 2011 3 414–427 DOI: 10.1002/wics.155

This article is categorized under:

Applications of Computational Statistics > Clinical Trials
Choosing the number of clusters
Authors: Mirkin Boris
Published: March 2011

The issue of determining ‘the right number of clusters’ is attracting ever growing interest. The paper reviews published work on the issue with respect to mixture of distributions, partition, especially in k‐means clustering, and hierarchical cluster structures. Some perspective directions for further developments are outlined. © 2011 John Wiley & Sons, Inc. WIREs Data Mining Knowl Discov 2011 1 252–260 DOI: 10.1002/widm.15

This article is categorized under:

Algorithmic Development > Structure Discovery

Technologies > Structure Discovery and Clustering
Controlling forces and pathways in self‐assembly using viruses and DNA
Authors: Keum Jung‐Won , Hathorne Adam P. , Bermudez Harry
Published: March 2011

The ability of both viruses and DNA to self‐assemble in solution has continues to enable numerous applications at the nanoscale. Here we review the relevant interactions dictating the assembly of these structures, as well as discussing how they can be exploited experimentally. Because self‐assembly is a process, we discuss various strategies for achieving spatial and temporal control. Finally, we highlight a few examples of recent advances that exploit the features of these nanostructures. WIREs Nanomed Nanobiotechnol 2011 3 282–297 DOI: 10.1002/wnan.129

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Super‐resolution microscopy for nanosensing
Authors: Galbraith James A. , Galbraith Catherine G.
Published: March 2011

The recent advances in optical microscopy enable the simultaneous visualization of thousands of structural and signaling molecules as they dynamically rearrange within living cells. Super‐resolution microscopy offers an unprecedented opportunity to define the molecular mechanisms of nanosensing through direct observation of protein movement. This technology provides a real‐time readout of how genetically targeted molecular perturbations affect protein interactions. As we strive to meet the challenge offered by the opportunity to ask questions about the mechanism of cell that we never thought we could answer, we need to be aware that the new technologies are still evolving. The current limitations of each technique need to be considered when matching them to specific biological questions. In this review, we briefly describe the principles of super‐resolution optical microscopy and focus on comparing the characteristics of each technique that are important for their use in studying nanosensing in the cellular microenvironment. WIREs Nanomed Nanobiotechnol 2011 3 247–255 DOI: 10.1002/wnan.130

This article is categorized under:

Diagnostic Tools > Biosensing

Nanotechnology Approaches to Biology > Cells at the Nanoscale

Diagnostic Tools > In Vivo Nanodiagnostics and Imaging