bluuebunny/crossref_metadata_2025_split huggingface dataset:
BOLD background gradient contributions in diffusion‐weighted fMRI—comparison of spin‐echo and twice‐refocused spin‐echo sequences
Authors: Pampel André , Jochimsen Thies H. , Möller Harald E. 
Published: March 2010

AbstractThe interaction (‘cross terms’) between diffusion‐weighting gradients and susceptibility‐induced background gradient fields around vessels has an impact on apparent diffusion coefficient (ADC) measurements and diffusion‐weighted functional magnetic resonance imaging (DFMRI) experiments. Monte‐Carlo (MC) simulations numerically integrating the Bloch equations for a large number of random walks in a vascular model were used to investigate to what extent such interactions would influence the extravascular signal change as well as the ADC change observed in DFMRI experiments. The vascular model consists of a set of independent, randomly oriented, infinite cylinders whose internal magnetic susceptibility varies as the state changes between rest and activation. In such a network, the cross terms result in the observation of a functional increase in ADC accompanied by a descending percent signal change with increasing diffusion weighting. It is shown that the twice‐refocused spin‐echo sequence permits sufficient yet not total suppression of such effects compared to the standard Stejskal‐Tanner spin‐echo diffusion weighting under experimentally relevant conditions. Copyright © 2010 John Wiley & Sons, Ltd.
Primary kinetic hydrogen isotope effects in deprotonations of carbon acids
Authors: Watt C. Ian F. 
Published: March 2010

AbstractThe mechanisms of deprotonation of carbon acids are reviewed to emphasise the important kinetic consequences associated with the internal and solvent reorganisation in forming the conjugate base. Some practicalities of measurements of kinetic hydrogen isotope effects are then considered to show how competing reactions, exchange and mechanistic branching might affect these measurements. Finally, isotopic rate ratios (kH/kD) have been collected for non‐enzymic deprotonations of carbon acids for which temperature dependences have also been determined. All examples contain nitro groups. For reactions in hydroxylic solvents, only two examples are found for which kH/kD > 8 at 25 °C (28.8 and 10.7), possibly indicating a tunnelling contribution. In both cases, values of E–E are larger and values of AH/AD smaller than the range expected (E–E = 4.54 kJ mol−1 and 0.7 < AH/AD < 1.4) for effects arising from zero‐point energy differences with no tunnelling contributions. For reactions in aprotic solvents, isotope effects are larger (12.1 < kH/kD < 19.6), but again, the largest of these (19.6 and 15.8) are associated with elevated values of E–E and small values of AH/AD. It is pointed out that behaviour of this type is accommodated by corrections to the semi‐classical model with shallow tunnelling maximised by high symmetrical barriers. No examples have been found in which large effects are associated with large values of AH/AD and small values of E–E.Comparisons are made with two recently reported enzyme‐catalysed reactions involving deprotonation of nitroalkanes. Copyright © 2010 John Wiley & Sons, Ltd.
Exploring the links between physical activity and posttraumatic growth in young adult cancer survivors
Authors: Love Caitlin , Sabiston Catherine M. 
Published: March 2010

AbstractObjective: Set within a posttraumatic growth (PTG) framework, the purpose of this investigation was to explore social support and enduring distress as predictors of psychological growth. The moderating role of physical activity was also examined.Method: Sixty‐four young adult cancer survivors (Mage=28.83, SD=5.5 years) completed a survey assessing constructs within the PTG model, cancer and personal descriptive, and physical activity.Results: In a hierarchical regression analysis, stress (β=−0.04) and social support (β=0.46) were significant predictors of psychological growth (R2=0.24). The physical activity by social support interaction accounted for an additional 12.8% of the variance (β=−0.52), suggesting a strong positive correlation between social support and psychological growth in inactive individuals and a much weaker correlation for active individuals.Conclusion: These findings highlight the importance for young adult cancer survivors to seek social support, adopt appropriate coping strategies to endure distress, and to engage in regular physical activity to foster experiences of psychological growth following diagnosis and treatment for cancer. Copyright © 2010 John Wiley & Sons, Ltd.
Associating biosensing properties with the morphological structure of multilayers containing carbon nanotubes on field‐effect devices
Authors: Siqueira José R. , Bäcker Matthias , Poghossian Arshak , Zucolotto Valtencir , Oliveira Osvaldo N. , Schöning Michael J. 
Published: March 2010

AbstractThe control of molecular architecture provided by the layer‐by‐layer (LbL) technique has led to enhanced biosensors, in which advantageous features of distinct materials can be combined. Full optimization of biosensing performance, however, is only reached if the film morphology is suitable for the principle of detection of a specific biosensor. In this paper, we report a detailed morphology analysis of LbL films made with alternating layers of single‐walled carbon nanotubes (SWNTs) and polyamidoamine (PAMAM) dendrimers, which were then covered with a layer of penicillinase (PEN). An optimized performance to detect penicillin G was obtained with 6‐bilayer SWNT/PAMAM LbL films deposited on p‐Si‐SiO2‐Ta2O5 chips, used in biosensors based on a capacitive electrolyte‐insulator‐semiconductor (EIS) and a light‐addressable potentiometric sensor (LAPS) structure, respectively. Field‐emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) images indicated that the LbL films were porous, with a large surface area due to interconnection of SWNT into PAMAM layers. This morphology was instrumental for the adsorption of a larger quantity of PEN, with the resulting LbL film being highly stable. The experiments to detect penicillin were performed with constant‐capacitance (ConCap) and constant‐current (CC) measurements for EIS and LAPS sensors, respectively, which revealed an enhanced detection signal and sensitivity of ca. 100 mV/decade for the field‐effect sensors modified with the PAMAM/SWNT LbL film. It is concluded that controlling film morphology is essential for an enhanced performance of biosensors, not only in terms of sensitivity but also stability and response time.
Customized impedance spectroscopy device as possible sensor platform for biosensor applications
Authors: van Grinsven Bart , Vandenryt Thijs , Duchateau Stijn , Gaulke Andreas , Grieten Lars , Thoelen Ronald , Ingebrandt Sven , De Ceuninck Ward , Wagner Patrick 
Published: March 2010

AbstractA new impedance spectroscopy unit is developed, fully customized to become a vital part of label free biosensor arrays with possible applications in DNA and protein sensing. Test measurements are conducted to explore the accuracy and specificity of the system, both under electronic lab conditions as well as under wet cell conditions with synthetic‐diamond based sensor electrodes. The impedance of seven resistors was monitored for 17 h and a maximum error <0.02% was found. Furthermore, the impedance of PBS at different concentrations was monitored for 60 min per concentration and a different impedance for each concentration was detected. The impedance is also monitored for NaOH, PBS and nuclease free water at different temperatures with a total duration of 60 min per fluid. Systematically different impedances for each temperature per fluid were found and the temperature coefficients were determined. All test measurements lead to results well within specification.
Characterization of core/shell nanoparticle thin films for gas analytical applications
Authors: Fuchs M. , Breitenstein D. , Fartmann M. , Grehl T. , Kayser S. , Koester R. , Ochs R. , Schlabach S. , Szabó D. V. , Bruns M. 
Published: March 2010

AbstractGas analytical microsystems such as the Karlsruhe micro nose (KAMINA) can be improved toward higher sensitivity when using SnO2 nanoparticle thin films instead of well‐established sputtered layers. For achieving long‐term stability, such nanoparticles must be prevented from growing and agglomerating. A very promising approach is to coat SnO2 nanoparticles with an open‐pored SiO2 shell, simply acting as a spacer, while preserving electrical contact between adjacent core particles. Such nanoparticulate thin films can easily be realized by the gas‐phase Karlsruhe microwave plasma process (KMPP). This provides an all‐in‐one approach to synthesize particles with diameters less than 10 nm, to coat them in situ with a protective ultrathin SiO2 shell in a downstream step and to finally deposit the core/shell particles solvent‐free onto prefabricated micro devices.The present study focuses on the surface analytical characterization of 200 nm thin films consisting of SnO2 core/SiO2 shell nanoparticles with various shell designs. For this purpose, the SiO2 shell thickness was systematically increased while keeping the SnO2 core size constant. X‐ray photoelectron spectroscopy (XPS) provides information concerning chemical binding states and shell thickness in a nondestructive manner. Angle‐resolved XPS together with transmission electron microscopy (TEM) validate the achieved core/shell structure. In the case of the desired ultrathin SiO2 shells, low‐energy ion scattering (LEIS) is solely the suitable means to prove that Sn and Si are the constituents of the outermost monolayer of the spherical particles and it demonstrates the attainability of open‐pored coatings. Copyright © 2010 John Wiley & Sons, Ltd.
Predicting the wettability of patterned ITO surface using ToF‐SIMS images
Authors: Yang L. , Shard A. G. , Lee J. L. S. , Ray S. 
Published: March 2010

AbstractPartial least squares (PLS) regression has been increasingly used as a tool for modelling linear relations between multivariate surface analytical measurements and measures of performance. However, the use of PLS to obtain quantitative predictions has only been partially explored. In this study, we construct a PLS model using time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and water contact angle (WCA) data obtained from a series of differently treated indium tin oxide (ITO) surfaces. This model displays a reasonable correlation between the WCA values and the SIMS data. To validate the model, ITO surfaces patterned with different areas of wettability were examined using ToF‐SIMS imaging to produce WCA maps. The PLS model was applied to predict the spatial variation in WCA across the sample. The direct measurement of WCA on the patterned ITO surface was achieved using a small‐scale interval grid from picolitre volume water droplets. We present the correlations between the predicted WCA from SIMS and the measured WCA, and highlight the discrepancies that arises in the comparison of the two datasets. This work is of direct benefit to industries where wettability is crucial but direct contact angle measurements are acquired on a scale smaller than it is possible to produce liquid drops, such as the plastic electronics and microfluidics industries. Copyright © 2010 John Wiley & Sons, Ltd.
Corrosion behavior under accelerated SO2 corrosion tests of thin iron nitride films prepared by DIBS
Authors: Marco J. F. , Herranz T. , Gracia M. , Gancedo J. R. , Moutinho F. , Prieto P. , Sanz J. M. 
Published: March 2010

AbstractWe report on the corrosion behavior of thin films, prepared by dual ion beam sputtering (DIBS), containing different concentrations of γ′‐and ε‐iron nitride phases. When deposited on Si wafers, the film containing almost equal amounts of γ′‐Fe4N and ε‐Fe3−xN phases shows the highest corrosion resistance. When deposited on iron substrates, all the films show almost total chemical degradation. We attribute this to the open microporosity of the different films deposited. Copyright © 2010 John Wiley & Sons, Ltd.
Chemical and electrochemical grafting of polyaniline on aniline‐terminated porous silicon
Authors: Chiboub Nawel , Boukherroub Rabah , Szunerits Sabine , Gabouze Noureddine , Moulay Saad , Sam Sabrina 
Published: March 2010

AbstractWe report, herein, on the preparation of polyaniline (PANi)/porous silicon (PSi) hybrid material. High surface area PSi substrates were obtained by electrochemical etching of crystalline silicon in HF‐based solutions. The freshly prepared PSi surface was first oxidized by UV/ozone and then reacted with 3‐bromopropyltrichlorosilane under an inert atmosphere to yield a brominated PSi surface. Aniline‐terminated PSi surface was formed by chemical reaction of the brominated PSi layer with aniline molecules. Finally, the polymerization was performed by either chemical method via an oxidative polymerization or electrochemical process using cyclic voltammetry. The PANi grafted by chemical or electrochemical methods on aniline‐terminated PSi surface exhibits a better chemical stability and a high resistance to harsh environments, as compared to PANi electrodeposited directly onto an oxidized PSi surface. This highlights the advantage of covalent grafting of PANi on the aniline‐modified PSi substrate. The composition, morphology and other physical properties of the resulting PANi/PSi hybrid structure were examined by Fourier transform infrared spectroscopy (FTIR), XPS, SEM and SIMS. The results clearly indicate that the polymerization takes place throughout the porous layer. Copyright © 2010 John Wiley & Sons, Ltd.
Rapid identification of bacteria and yeast using surface‐enhanced Raman scattering
Authors: Culha Mustafa , Kahraman Mehmet , Çam Dilek , Sayın Ismail , Keseroǧlu Kemal 
Published: March 2010

AbstractSurface‐enhanced Raman scattering (SERS) is a powerful technique used for obtaining chemical information about the molecules and molecular structures in the vicinity of surfaces of noble metal nanostructures. The chemical information acquired through SERS can be used for not only characterization but also detection and identification. In a clinical setting, rapid and accurate identification of micro‐organisms is critical. The biochemical information collected through the SERS spectra can be used for quick identification of micro‐organisms. The concentrated silver colloidal nanoparticles (AgNPs) are simply mixed with micro‐organisms after culturing, and their SERS spectra acquired. Since the nanoparticles are in contact with the cell wall of the micro‐organism, the biochemical information obtained is mostly assumed as originating from the cell wall which the AgNPs are in contact with, and is considered as the ‘fingerprint’ of the micro‐organism, which can be used for the identification. Since a SERS spectrum can be acquired only in seconds, the obtained spectrum can be used for fast micro‐organism identification. The reproducibility of the spectra obtained from micro‐organisms is first tested, and then the obtained spectra are used for the goal. The identification of micro‐organisms in mixtures is also attempted in model mixtures. It is demonstrated that the SERS can be used for fast and accurate identification of micro‐organisms such as bacteria and yeast, even in their mixtures. Four bacteria, i.e. Shigella sonnei, Erwinia amylovara, Proteus vulgaris and DH5α (E. coli strain), and three yeast cells, i.e. Hyphopichia burtonii, Candida parapsilosis and Filobasidiella neoformans are used as model micro‐organisms in the study. Copyright © 2010 John Wiley & Sons, Ltd.
Comparison of the protective effect of aromatic thiols adsorbed on copper
Authors: Di Castro V. , Beccari M. , Bruni F. , Caprioli F. , Decker F. 
Published: March 2010

AbstractStability and protection of copper from atmospheric oxidation, by aromatic thiolate adlayers obtained by adsorption of benzenethiol and 2‐naphthalenthiol from solution, has been investigated by XPS. The adsorbed molecules do not show sulfur oxidation in air and in acid solution. Both the studied molecules clearly protect the copper surface from oxidation, reducing oxide and hydroxide formation in a similar way, despite differences in the structure. The trend of the O/Cu ratio and the stability of the thiolate adlayers are indicative of oxidation at defects of the self‐assembled monolayers where the copper surface is not well protected. Copyright © 2010 John Wiley & Sons, Ltd.
Electrochemical grafting of poly(3‐hexylthiophene) on porous silicon for gas sensing
Authors: Belhousse S. , Boukherroub R. , Szunerits S. , Gabouze N. , Keffous A. , Sam S. , Benaboura A. 
Published: March 2010

AbstractThe paper reports on the preparation of a porous silicon (PSi)/poly(3‐hexylthiophene) hybrid structure and its application in gas sensing. The poly(3‐hexylthiophene) was covalently grafted on the PSi surface in a stepwise process. Electropolymerizable thiophene groups were covalently linked to an azide‐terminated PSi surface using ‘click chemistry’ approach. Poly(3‐hexylthiophene) films were grown on the thiophene‐terminated PSi interface using electropolymerization in acetonitrile in the presence of 3‐hexylthiophene monomer.Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and electrochemical measurements were performed to follow the chemical composition and structural changes after each step.The sensitivity, response time and capacitance response of the device to gas environment have been investigated. The results show that current–voltage characteristics are modified by the presence of the gas, and the sensor displays a rapid and reversible response at room temperature. Copyright © 2010 John Wiley & Sons, Ltd.
2010 Alzheimer's disease facts and figures
Authors:   Alzheimer's Association
Published: March 2010

Alzheimer's disease (AD) is the seventh leading cause of all deaths in the United States and is virtually tied with the sixth leading cause of death—diabetes. AD is the fifth leading cause of death in Americans aged 65 and older. Although other major causes of death have been on the decrease, deaths because of AD have been rising dramatically. Between 2000 and 2006, heart disease deaths decreased 11.1%, stroke deaths decreased 18.2%, and prostate cancer–related deaths decreased 8.7%, whereas deaths because of AD increased 46.1%.Older African‐Americans and Hispanics are more likely than older white Americans to have AD or other dementia. Current estimates are that African‐Americans are about 2 times more likely, and Hispanics about 1.5 times more likely, than their white counterparts to have these conditions. However, the relationship of race and ethnicity to the development of AD and other dementias is complex and not fully understood.In 2009, nearly 11 million family and other unpaid caregivers provided an estimated 12.5 billion hours of care to persons with AD and other dementias; this care is valued at nearly $144 billion. Medicare payments for services to beneficiaries aged 65 years and older with AD and other dementias are three times higher than for beneficiaries without these conditions. Total payments for 2010 for health care and long‐term care services for people aged 65 and older with AD and other dementias are expected to be $172 billion (not including the contributions of unpaid caregivers).An estimated 5.3 million Americans have AD; approximately 200,000 persons under age 65 with AD comprise the younger‐onset AD population. Every 70 seconds, someone in America develops AD; by 2050 the time of every 70 seconds is expected to decrease to every 33 seconds. Over the coming decades, the baby boom population is projected to add 10 million people to these numbers. In 2050, the incidence of AD is expected to approach nearly a million people per year, with a total estimated prevalence of 11–16 million people. Dramatic increases in the numbers of “oldest old” (aged 85 years and older) across all racial and ethnic groups will also significantly affect the numbers of people living with AD.This report provides information to increase understanding of the public health effect of AD, including incidence and prevalence, mortality, costs of care, and effect on caregivers and society in general. This report also sets the stage for better understanding the relationship between race and ethnicity and the development of AD and other dementias.
EXISTENCE OF RESOLVENT FOR VOLTERRA INTEGRAL EQUATIONS ON TIME SCALES
Authors: ADıVAR MURAT , RAFFOUL YOUSSEF N. 
Published: March 2010

AbstractWe introduce the concept of ‘shift operators’ in order to establish sufficient conditions for the existence of the resolvent for the Volterra integral equation on time scales. The paper will serve as the foundation for future research on the qualitative analysis of solutions of Volterra integral equations on time scales, using the notion of the resolvent.
Sudden sensorineural hearing loss: when is it idiopathic?
Authors: Wilson H , Alderson D J 
Published: March 2010

AbstractObjective: To highlight the importance of assessing the certainty of a diagnosis of idiopathic sudden sensorineural hearing loss, and of modifying patient management accordingly.Case report: A patient presented with sudden sensorineural hearing loss in the right ear. Following assessment and preliminary investigation, a diagnosis of idiopathic sudden sensorineural hearing loss was made. Steroid treatment was commenced. Two weeks later, the patient experienced sudden sensorineural hearing loss in the left ear, and scalp tenderness. Subsequent biopsy confirmed giant cell arteritis.Conclusions: Management of idiopathic sudden sensorineural hearing loss should be guided by the level of certainty of diagnosis. If there is relative uncertainty, risk factors for specific diagnoses should be sought, the patient should be followed more closely, and investigation should be tailored appropriately. Giant cell arteritis should be considered in patients older than 50 years, those exhibiting suggestive signs or symptoms, and those with elevated inflammatory markers or deranged liver function tests.
Pathogenic characterization in mice of Neospora caninum isolates obtained from asymptomatic calves
Authors: PEREIRA GARCÍA-MELO D. , REGIDOR-CERRILLO J. , COLLANTES-FERNÁNDEZ E. , AGUADO-MARTÍNEZ A. , DEL POZO I. , MINGUIJÓN E. , GÓMEZ-BAUTISTA M. , ADURIZ G. , ORTEGA-MORA L. M. 
Published: March 2010

SUMMARYIn this study, we characterized 8 new isolates obtained from healthy but congenitally infected calves using a BALB/c mouse model. Neospora caninum-infected mice survived without exhibiting any clinical signs of disease. Nevertheless, differences among isolates in parasite organ distribution, parasite burden and the severity of histopathological lesions were determined. Mice infected with the Nc-Spain 5H, Nc-Spain 7 and Nc-Spain 9 isolates showed higher parasite burdens and more severe brain lesions during the late phase of infection compared to mice infected with the Nc-Spain 2H, Nc-Spain 3H or Nc-Spain 6 isolates. Furthermore, differences in the immunoglobulin IgG1 and IgG2a isotype kinetics induced by these isolates were observed, with a more rapid IgG2a response seen in mice infected with the Nc-Spain 2H and Nc-Spain 3H isolates. These results confirm the intra-species variability of N. caninum pathogenicity.