bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of entorhinal cortex atrophy between early‐onset and late‐onset Alzheimer's disease using the VSRAD, a specific and sensitive voxel‐based morphometry
Authors: Shibuya Yuzuru , Kawakatsu Shinobu , Hayashi Hiroshi , Kobayashi Ryota , Suzuki Akihito , Sato Chikako , Otani Koichi 
Published: May 2012

BackgroundThe most characteristic symptom of Alzheimer's disease (AD) is episodic memory impairment, which is closely associated with atrophy of the entorhinal cortex. Meanwhile, atypical symptoms are more frequent in early‐onset AD than in late‐onset AD, suggesting that the former subtype has less atrophy in the entorhinal cortex. Therefore, we investigated whether the degree of atrophy in the entorhinal cortex is different between the two subtypes of AD using the voxel‐based specific regional analysis system for AD (VSRAD) targeting this region.MethodsThe subjects consisted of 198 patients with AD. They were divided into two groups, that is, the early‐onset AD group with the onset under age 65 years (n = 18) and the late‐onset AD group with the onset at age 65 years or over (n = 180). The degree of atrophy in the entorhinal cortex was quantified by application of the VSRAD to magnetic resonance imaging data, and a Z‐score >2 was defined as significant atrophy according to previous studies.ResultsThe early‐onset group had significantly lower Z‐scores than the late‐onset group (mean ± SD: 1.83 ± 0.92 vs 2.90 ± 1.40, p < 0.01). The analysis of covariance with possible confounding factors as covariates also showed that Z‐scores were significantly lower in the early‐onset group than in the late‐onset group (p < 0.01). The proportion of patients with atrophy was significantly lower in the early‐onset group than in the late‐onset group (44% vs 71%, p < 0.05).ConclusionsThe present study using the VSRAD suggests that early‐onset AD shows less atrophy in the entorhinal cortex than late‐onset AD. Copyright © 2012 John Wiley & Sons, Ltd.
ZERO‐INFLATED ENDOGENOUS COUNT IN CENSORED MODEL: EFFECTS OF INFORMAL FAMILY CARE ON FORMAL HEALTH CARE
Authors: Lee Myoung‐jae , Kim Young‐sook 
Published: May 2012

SUMMARYIf informal family health care is a substitute for formal health care, then there is a scope to reduce formal health care cost by promoting informal family health care. With the use of Korean data for the elderly, this paper estimates the effects of informal family health care on formal health care, where the former is measured by the number of caregivers and the latter is measured by the formal health care expenditure. This task, however, poses a number of difficulties. The first is that the number of the family caregivers is an endogenous count regressor. The second is that there are too many zeros in the count (85%). The third is that the response variable also has a nontrivial proportion of zeros (14%). This paper overcomes these problems by combining ‘control function approach’, ‘zero‐inflated’ counts, and a semiparametric estimator for censored models. The resulting procedure avoids strong parametric assumptions and behaves well computationally. Our main empirical finding is that informal family health care has a large substitute effect for diabetics and that there are also weak evidences that informal family health care has substitute effects for high blood pressure and mental diseases. Copyright © 2012 John Wiley & Sons, Ltd.
Assessment of current water pollution loads in Europe: estimation of gridded loads for use in global water quality models
Authors: Williams Richard , Keller Virginie , Voß Anja , Bärlund Ilona , Malve Olli , Riihimäki Juha , Tattari Sirkka , Alcamo Joseph 
Published: May 2012

AbstractA methodology for estimating the loading of pollutants to water courses across all of pan‐Europe, an area reaching to the River Don in the east and including some Mediterranean rim countries in the near east and North Africa is presented. Loadings come from point (domestic effluent, manufacturing discharge and urban runoff) and diffuse (scattered settlements and land use) sources. The loads have been calculated on a countrywide basis using readily available data held by national and international bodies. These loads are downscaled to the grid cells (5 × 5′) used in the model. The paper illustrates the general framework for making these calculations using biochemical oxygen demand (BOD) and total dissolved solids (TDS), and estimated loads for periods representing 1990, 1995, 2000 and 2005 are presented as maps.According to the model, in 2005, annual BOD loads came mostly from domestic effluent (3 Mt) and diffuse sources (5 Mt, mainly attributed to livestock). Manufacturing, urban runoff and scattered settlements contributed annual loads of 0.33, 0.15 and 1.2 Mt, respectively. For TDS, annual manufacturing loads were 65 Mt and annual domestic loads 28 Mt. Diffuse loadings (36 Mt) came from irrigated land and therefore showed a different spatial pattern from BOD. The total annual diffuse load of TDS was 56 Mt. Scattered settlements contributed only 9.6 Mt to the total pan‐European load. Some limited comparison of the loads estimated in this study for BOD with those estimated by others for countries and large catchments in the area has been carried out. Copyright © 2012 John Wiley & Sons, Ltd.
CONSTRUCTION CHARACTERISTICS AND MANAGEMENT PRACTICES OF IN‐FARM IRRIGATION PONDS IN INTENSIVE AGRICULTURAL SYSTEMS — AGRONOMIC AND ENVIRONMENTAL IMPLICATIONS
Authors: Juan Melchor , Casas Jesús , Bonachela Santiago , Fuentes‐Rodríguez Francisca , Gallego Irene , Elorrieta María Antonia 
Published: May 2012

ABSTRACTThe structural and management characterization of 101 ponds, used for greenhouse drip irrigation, was assessed on the south‐eastern coast of Spain, with the objective of proposing more sustainable management practices. Different management methods were carried out by growers with the aim of controlling pond biological activity and improving the irrigation water quality. Pond covering was highly effective in preventing submerged aquatic vegetation (SAV) development but the high cost of installing and maintaining covers limit its use. Pond dredging and biocide treatments were relatively expensive and ineffective in controlling mid and long‐term SAV development. No clear criteria were observed for biocide use (products, dosage and scheduling). SAV developed spontaneously in 48.5% of uncovered ponds. Chara species, which tend to form dense meadows in the pond bottom and are highly valuable for aquatic biodiversity conservation, may improve the water quality and are unlikely to hinder agricultural pond uses. More sustainable management practices based on preserving SAV in ponds, particularly charophytes, and reducing or suppressing dredging and biocide use may be successful in accomplishing both agronomic and environmental pond functions. Copyright © 2012 John Wiley & Sons, Ltd.
Clinical course of non‐specific low back pain: A systematic review of prospective cohort studies set in primary care
Authors: Itz C.J. , Geurts J.W. , van Kleef M. , Nelemans P. 
Published: May 2012

AbstractBackground and objectiveNon‐specific low back pain is a relatively common and recurrent condition for which at present there is no effective cure. In current guidelines, the prognosis of acute non‐specific back pain is assumed to be favourable, but this assumption is mainly based on return to function. This systematic review investigates the clinical course of pain in patients with non‐specific acute low back pain who seek treatment in primary care.Databases and data treatmentIncluded were prospective studies, with follow‐up of at least 12 months, that studied the prognosis of patients with low back pain for less than 3 months of duration in primary care settings. Proportions of patients still reporting pain during follow‐up were pooled using a random‐effects model. Subgroup analyses were used to identify sources of variation between the results of individual studies.ResultsA total of 11 studies were eligible for evaluation. In the first 3 months, recovery is observed in 33% of patients, but 1 year after onset, 65% still report pain. Subgroup analysis reveals that the pooled proportion of patients still reporting pain after 1 year was 71% at 12 months for studies that considered total absence of pain as a criterion for recovery versus 57% for studies that used a less stringent definition. The pooled proportion for Australian studies was 41% versus 69% for European or US studies.ConclusionsThe findings of this review indicate that the assumption that spontaneous recovery occurs in a large majority of patients is not justified. There should be more focus on intensive follow‐up of patients who have not recovered within the first 3 months.
Polyurethane modified with an antithrombin‐heparin complex via polyethylene oxide linker/spacers: Influence of PEO molecular weight and PEO‐ATH bond on catalytic and direct anticoagulant functions
Authors: Sask Kyla N. , Berry Leslie R. , Chan Anthony K. C. , Brash John L. 
Published: May 2012

AbstractA segmented polyurethane (PU) was modified with polyethylene oxides (PEO) of varying molecular weight and end group. The PEO served as linker/spacers to immobilize an antithrombin‐heparin (ATH) anticoagulant complex on the PU. Isocyanate groups were introduced into the PU to enable attachment of either “conventional” homo‐bifunctional dihydroxy‐PEO (PEO‐OH surface) or a hetero‐bifunctional amino‐carboxy‐PEO (PEO‐COOH surface). The PEO surfaces were functionalized with N‐hydroxysuccinimide (NHS) groups using appropriate chemistries, and ATH was attached to the distal NHS end of the PEO (PEO‐OH‐ATH and PEO‐COOH‐ATH surfaces). Water contact angle and fibrinogen adsorption measurements showed increased hydrophilicity and reduced fibrinogen adsorption from buffer on all PEO surfaces compared to unmodified PU. ATH uptake on NHS‐functionalized PEO was quantified by radiolabeling. Despite the different PEO molecular weights and end groups, and NHS‐functionalization chemistries, the surface densities of ATH were similar. The adsorption of fibrinogen and antithrombin (AT) from plasma was measured in a single experiment using dual radiolabeling. On PEO‐ATH surfaces fibrinogen adsorption was minimal while AT adsorption was high showing the selectivity of the heparin moiety of ATH for AT. The PEO‐COOH‐ATH surfaces showed slightly greater AT adsorption than the PEO‐OH‐ATH surfaces. Thrombin adsorption on all of the PEO‐ATH surfaces was greater than on the corresponding PEO surfaces without ATH, and was highest on the PEO‐OH‐ATH, suggesting potential anticoagulant properties for this surface via direct thrombin inhibition by the AT portion of ATH. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A 100A:2821–2828, 2012.
Comment on the paper “Extensive Theoretical Studies of a New Energetic Material: Tetrazino‐Tetrazine‐Tetraoxide (TTTO)” by Xinli Song, Jicun Li, Hua Hou, and Baoshan Wang
Authors: Jorgensen Kameron R. , Wilson Angela K. 
Published: May 2012

AbstractDiscrepancies are noted in the implementation and presentation of the ccCA methodology in a previous publication, “Extensive Theoretical Studies of a New Energetic Material: Tetrazino‐tetrazine‐tetraoxide (TTTO)” by Xinli Song, Jicun Li, Hua Hou, and Baoshan Wang. The enthalpy of formation for TTTO has been re‐evaluated using the correct implementation of the ccCA methodology, demonstrating the results to be comparable to those of other ab initio composite methods. © 2012 Wiley Periodicals, Inc.
Comparative DFT study of N2 and no adsorption on vanadium clusters Vn (n = 2–13)
Authors: Wu Guangfen , Yang Mingli , Guo Xingyu , Wang Jinlan 
Published: May 2012

AbstractUsing gradient‐corrected density functional theory, we have comparatively studied the adsorption properties of diatomic molecules N2 and NO on vanadium clusters up to 13 atoms. Spontaneous dissociation is found for N2 adsorbing on Vn with n = 4–6, 12, and for NO with n = 3–12, respectively, whereas for the rest of the clusters, N2 (NO) molecularly adsorbs on the cluster for all the possible sites. The incoming N2 retains the magnetism of Vn except for V2 and V6 whose moments are quenched from 2 μB to zero. Consequently, the moments of VnN2 (n = 2–13) show even/odd oscillation between 0 and 1 μB. On the adsorption of NO, the magnetic moments of Vn with closed electronic shell are raised to 1 μB at n = 4, 8, and 10, and 3 μB at n = 12, whereas for open shell clusters, their magnetic moments increase for n = 5 and 9 and decrease for n = 2, 3, 5–7, 11, and 13 by 1 μB. These findings are rationalized by combinatory analysis from several aspects, for example, the geometry and stability of bare clusters, charge transfer induced by the adsorption, feature of frontier orbitals, and spin density distribution. © 2012 Wiley Periodicals, Inc.
Coral: QSPR modeling of rate constants of reactions between organic aromatic pollutants and hydroxyl radical
Authors: Toropov A. A. , Toropova A. P. , Rasulev B. F. , Benfenati E. , Gini G. , Leszczynska D. , Leszczynski J. 
Published: May 2012

AbstractThe rate constants (KOH) of reactions between 78 organic aromatic pollutants and hydroxyl radical were examined. Simplified molecular input line entry system was used as representation of the molecular structure of the pollutants. Quantitative structure–property relationships was developed using CORAL software (http://www.insilico.eu/CORAL) for four random splits of the data into the subtraining, calibration, and test sets. The obtained results reveal good predictive potential of the applied approach: correlation coefficients (r2) for the test sets of the four random splits are 0.75, 0.91, 0.84, and 0.80. Using the Monte Carlo method CORAL software generated the optimal descriptors for one‐variable models. The reproducibility of each model was tested performing three runs of the Monte Carlo optimization. The current data were compared to previous results and discussed. © 2012 Wiley Periodicals, Inc.
Gas‐phase reactions of SiHn+ (n = 1,2) with NF3: A computational investigation on the detailed mechanistic aspects
Authors: Antoniotti Paola , Bottizzo Elena , Borocci Stefano , Giordani Maria , Grandinetti Felice 
Published: May 2012

AbstractThe mechanism of the gas‐phase reactions of SiHn+ (n = 1,2) with NF3 were investigated by ab initio calculations at the MP2 and CAS‐MCSCF level of theory. In the reaction of SiH+, the kinetically relevant intermediates are the two isomeric forms of fluorine‐coordinated intermediate HSi‐F‐NF2+. These species arise from the exoergic attack of SiH+ to one of the F atoms of NF3 and undergo two competitive processes, namely an isomerization and subsequent dissociation into SiF+ + HNF2, and a singlet‐triplet crossing so to form the spin‐forbidden products HSiF+ + NF2. The reaction of SiH2+ with NF3 involves instead the concomitant formation of the nitrogen‐coordinated complex H2Si‐NF3+ and of the fluorine‐coordinated complex H2Si‐F‐NF2+. The latter isomer directly dissociates into NF2+ + H2SiF, whereas the former species preferably undergoes the passage through a conical intersection point so to form a H2SiF‐NF2+ isomer, which eventually dissociates into H2SiF+ and NF2. © 2012 Wiley Periodicals, Inc.
Balancing target flexibility and target denaturation in computational fragment‐based inhibitor discovery
Authors: Foster Theresa J. , MacKerell Alexander D. , Guvench Olgun 
Published: May 2012

AbstractAccounting for target flexibility and selecting “hot spots” most likely to be able to bind an inhibitor continue to be challenges in the field of structure‐based drug design, especially in the case of protein–protein interactions. Computational fragment‐based approaches using molecular dynamics (MD) simulations are a promising emerging technology having the potential to address both of these challenges. However, the optimal MD conditions permitting sufficient target flexibility while also avoiding fragment‐induced target denaturation remain ambiguous. Using one such technology (Site Identification by Ligand Competitive Saturation, SILCS), conditions were identified to either prevent denaturation or identify and exclude trajectories in which subtle but important denaturation was occurring. The target system used was the well‐characterized protein cytokine IL‐2, which is involved in a protein–protein interface and, in its unliganded crystallographic form, lacks surface pockets that can serve as small‐molecule binding sites. Nonetheless, small‐molecule inhibitors have previously been discovered that bind to two “cryptic” binding sites that emerge only in the presence of ligand binding, highlighting the important role of IL‐2 flexibility. Using the above conditions, SILCS with hydrophobic fragments was able to identify both sites based on favorable fragment binding while avoiding IL‐2 denaturation. An important additional finding was that acetonitrile, a water‐miscible fragment, fails to identify either site yet can induce target denaturation, highlighting the importance of fragment choice. © 2012 Wiley Periodicals, Inc.
Enhancement of microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in a marine sediment by nanoscale zerovalent iron (NZVI) particles
Authors: Zanaroli Giulio , Negroni Andrea , Vignola Marta , Nuzzo Andrea , Shu Hung‐Yee , Fava Fabio 
Published: May 2012

AbstractBACKGROUND: Microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in contaminated sediments is characterized by long lag periods and low rates. Zerovalent iron is a source of cathodic hydrogen that has been proposed as an easily amendable agent to stimulate PCB microbial dechlorination. The objective of this study was to evaluate the effect of nanoscale zerovalent iron (NZVI) particles on the reductive dechlorination of Aroclor 1254 PCBs and on the indigenous microbial community in a marine sediment under in situ‐like biogeochemical conditions.RESULTS: A 30‐weeks lag phase followed by a modest dechlorination (5.0 ± 0.4 mol%) of hepta‐ through penta‐chlorinated PCBs occurred in NZVI‐free cultures during 36 weeks of incubation. NZVI (6.7 g kg−1) reduced the lag phase of PCB dechlorination by 10 weeks, leading to a four‐fold increase of the dechlorination extent at the end of the incubation. NVZI exerted some toxic effect on sulphate reducing bacteria, which were transiently inhibited until its complete oxidation occurred, and favoured the enrichment of a phylotype closely related to the PCB dehalorespiring bacterium Dehalobium chlorocoercia DF‐1, probably via the simultaneous partial inhibition of sulphate reducing bacteria and the release of molecular hydrogen. Finally, DGGE analysis showed that NZVI did not affect markedly the biodiversity of the indigenous microbial community.CONCLUSION: NZVI displayed a very high biostimulation effect on PCB microbial dechlorination and a very low impact on the sediment indigenous microbial community. Supplementation with NZVI particles might thus be a sustainable effective strategy to intensify PCB reductive dechlorination processes in marine sediments. Copyright © 2012 Society of Chemical Industry
Study of the conditions for multi‐modal chromatographic capture of Fab′ from dual‐salt precipitated E. coli homogenate
Authors: Balasundaram Bangaru , Chhatre Sunil , Arora Dhruv , Titchener‐Hooker Nigel J , Bracewell Daniel G 
Published: May 2012

AbstractBACKGROUND: In the commercial‐scale purification of immunotherapeutics, Protein A chromatography is employed routinely for its high binding capacity and selectivity. Nevertheless, matrix cost and ligand leaching issues remain and there are many alternatives such as ion‐exchange and multi‐modal resins that are less expensive. However, binding capacities are lower than Protein A owing to the co‐adsorption of protein impurities. One solution involves removing impurities before chromatography by precipitation and a potential approach presented in the literature recently employs a dual‐salt precipitation technique. The current study explores the impact of this upon the capture of an antibody fragment by a multimodal cation exchange resin.RESULTS: The dual salt precipitation procedure employed here removed 36% of the contaminant proteins. A microscale chromatography pipette tip approach was used in a high throughput screening format to scout rapidly for favourable binding conditions successfully. Higher binding capacities were achieved by activating the hydrophobic binding modality of the resin at feed ionic strengths of around 150 mS cm−1 using ammonium sulphate. This was better than using the ion‐exchange modality at below 10 mS cm−1.CONCLUSIONS: Dual salt precipitation followed by chromatographic capture using this resin were found to be complementary to one another since the removal of protein impurities by dual salt precipitation resulted in a two‐fold improvement in terms of binding capacity. © 2012 Society of Chemical Industry
Supercritical and enzymatic technologies for the production of lysophosphatidylcholine
Authors: Casado Víctor , Señorans Francisco.J , Reglero Guillermo , Torres Carlos F. 
Published: May 2012

AbstractBACKGROUNDThis study focuses on obtaining a highly purified lysophosphatidylcholine from phosphatidylcholine powder via hydrolysis, catalyzed by a phospholipase A2 in a solvent‐free medium, and subsequent purification either by organic solvent or by supercritical fluid extraction.RESULTSA solvent‐free hydrolysis reaction of phosphatidylcholine powder to produce lysophosphatidylcholine with residual phosphatidylcholine content lower than 10% has been described and scaled‐up. Supercritical fluid mixtures of carbon dioxide, ethanol and formic acid were studied at 250, bar 50 °C to selectively extract the free fatty acids fraction from hydrolyzed phosphatidylcholine. Finally, a solid product with lysophosphatidylcholine content of c. 95% (w/w) and with free fatty acids content of c. 5% (w/w) was attained. Under optimum conditions, the content of the original phosphatidylcholine in the lysophosphatidylcholine product was lower than 5% (w/w).CONCLUSIONSAn efficient hydrolysis of phosphatidylcholine by phospholipase A2 in a solvent‐free reaction was developed. In addition, three novel strategies for the purification of lysophosphatidylcholine have been developed: (1) hexane/formic acid extraction process, (2) supercritical CO2 extraction with ethanol as modifier, and (3) supercritical CO2 extraction with ethanol/formic acid as modifier. Copyright © 2012 Society of Chemical Industry
Differentiation of fresh and frozen/thawed fish, European sea bass (Dicentrarchus labrax), gilthead seabream (Sparus aurata), cod (Gadus morhua) and salmon (Salmo salar), using volatile compounds by SPME/GC/MS
Authors: Leduc François , Krzewinski Frédéric , Le Fur Bruno , N'Guessan Assi , Malle Pierre , Kol Ossarath , Duflos Guillaume 
Published: May 2012

AbstractBACKGROUND: A simple method based on solid phase microextraction/gas chromatography/mass spectrometry (SPME/GC/MS) was applied for studying the volatile profiles of whole fish samples of European sea bass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) and fillets of cod (Gadus morhua) and salmon (Salmo salar) during frozen storage in order to be able to differentiate a fresh product from one that has been frozen. Analysis of volatile compounds was performed on these two product types, fresh and after freezing/thawing following storage at − 20 °C for 30 and 90 days.RESULTS: More than a hundred volatile compounds were found by SPME/GC/MS. Statistical processing by principal component analysis and ascending hierarchical classification was used to classify the samples into categories and verify the possibility of separating fresh samples from those that had been frozen and thawed. The compounds to be used as differentiators were identified. Four compounds were common to all species: dimethyl sulfide, 3‐methylbutanal, ethyl acetate and 2‐methylbutanal. Not only were they found in larger quantities after thawing but they also increased with the duration of storage at − 20 °C.CONCLUSION: These four compounds can therefore be considered as potential markers of differentiation between a fresh product and one that has been frozen. Copyright © 2012 Society of Chemical Industry