bluuebunny/crossref_metadata_2025 huggingface dataset:
Feedback and regime shift of mire ecosystem in northern Japan
Authors: Nakayama Tadanobu
Published: April 2012

Because anthropogenic stressors have caused degradation of the Kushiro Mire, in subarctic northern Japan, seen as drying and invasion of alder‐dominant shrub forest, the Japanese government recently started a project to restore a meandering former river channel and so diminish the shrub forest and recover the mire ecosystem. This paper describes the further development of the National Integrated Catchment‐based Eco‐hydrology (NICE) model with surface‐unsaturated–saturated water processes and land‐surface processes assimilated with satellite data to include mutual interaction and feedback of hydrogeologic and vegetation dynamics in the mire. NICE iteratively simulated hydrologic cycle, elevation change, and vegetation succession, including the competition between two vegetation types (alder‐dominant shrub forest and reed–sedge vegetation), to evaluate nonlinear relationship between drying and alder invasion in the mire and to examine a method for mire recovery. NICE reproduced well the heterogeneous alder invasion in the mire, implying that the study made some progress in explaining the positive feedback between geomorphology and eco‐hydrology on irregular slopes and in heterogeneous vegetation, whereas most previous studies have considered regular slopes and their relation to string or maze patterns. Simulation results predicted that restoring meanders to the river channel would decrease the discharge and sediment loading of the river, increase the groundwater level downstream, and achieve a degree of mire recovery in the future. The heterogeneous vegetation succession is discussed in relation to regime shift in transient simulation. These results suggest the effectiveness of river restoration in conservation plans for mire recovery, and the importance of the process‐based model in assessing the linkage of hydrological change and vegetation succession. Copyright © 2012 John Wiley & Sons, Ltd.
COMMUNITY RESPONSE TO AQUIFER DEVELOPMENT: DISTINCT PATTERNS IN INDIA'S ALLUVIAL AND HARD ROCK AQUIFER AREAS
Authors: Shah Tushaar
Published: April 2012

The boom that India has experienced in groundwater irrigation is only weakly related to the availability of groundwater resources, long‐term recharge rates and even availability of surface canal infrastructure. Dependence on groundwater has increased in rich alluvial aquifers with ample storage as well as in poor hard rock aquifers with limited storage. The socio‐economic and environmental impacts of the over‐exploitation of groundwater are also equally pervasive. This paper shows that some, though not all, responses to groundwater over‐development from farming communities are different in ‘thick’ alluvial aquifer areas from ‘thin’ hard rock aquifer areas. In the former, users fail to comprehend their interdependence, and consequently, to behave like an ‘aquifer community’ sharing a limited resource. As individual users, they engage in competitive deepening of boreholes to chase declining water levels. In arid alluvial areas, there is no sign of groundwater users trying either supply‐ or demand‐side initiatives to make groundwater use sustainable. In contrast, many hard rock aquifer areas in India are seeing spontaneous initiatives from farmers, communities, NGOs and other players to cope with or counter aquifer depletion, mostly by individual or group efforts to increase groundwater recharge, but less so by making and enforcing rules to limit withdrawals. Copyright © 2012 John Wiley & Sons, Ltd.
ANALYSIS OF THE EMERGENCE AND EVOLUTION OF COLLECTIVE ACTION: AN EMPIRICAL CASE OF SPANISH GROUNDWATER USER ASSOCIATIONS
Authors: Rica Marta , López‐Gunn Elena , Llamas Ramón
Published: April 2012

This paper analyses the emergence and evolution of collective action in relation to intensive groundwater user by looking at the case of groundwater user associations in Spain. The paper analyses the rules in norm or constitutional level and the typology of collective organizations, to then offer an empirical analysis of the main factors in the emergence and evolution of collective action in Spanish groundwater user associations. It identifies some key endogenous and exogenous factors that either facilitate or hinder collective action by groundwater users, as well as documenting their evolution through time towards a more diverse institutional range, partly explained by reaching increasing resource limits, which triggers looking for additional resources to minimize and manage risk and uncertainty. Copyright © 2012 John Wiley & Sons, Ltd.
Bone remodeling after total hip arthroplasty with a short stemmed metaphyseal loading implant: Finite element analysis validated by a prospective DEXA investigation
Authors: Lerch Matthias , Kurtz Agnes , Stukenborg‐Colsman Christina , Nolte Ingo , Weigel Nelly , Bouguecha Anas , Behrens Bernd A.
Published: April 2012

In total hip arthroplasty (THA), short stemmed cementless implants are used because they are thought to stimulate physiological bone remodeling and reduce stress shielding. We performed a numerical investigation on bone remodeling after implantation of a specific short stemmed implant using finite element analysis (FEA). Overall bone mass loss was 2.8% in the entire femur. Bone mass decrease was mostly found in the proximal part of the calcar and in the greater trochanter due to the vast cross section of the implant, probably leading to stress shielding. In the diaphysis, no change in the apparent bone density was proven. The assumptions made agreed well with bone remodeling data from THA recipients who underwent dual‐energy X‐ray absorptiometry. However, the clinical investigation revealed a bone mass increase in the minor trochanter region that was less pronounced in the FEA. Further comparisons to other stem designs must be done to verify if the relative advantages of the investigated implant can be accepted. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1822–1829, 2012
Remarks on continuum cardinals on Boolean algebras
Authors: Monk J. Donald
Published: April 2012

We give some results concerning various generalized continuum cardinals. The results answer some natural questions which have arisen in preparing a new edition of 5. To make the paper self‐contained we define all of the cardinal functions that enter into the theorems here. There are many problems concerning these new functions, and we formulate some of the more important ones.
Entropy numbers of operators acting between vector‐valued sequence spaces
Authors: Edmunds David E. , Netrusov Yuri
Published: April 2012

Entropy numbers of operators acting between vector‐valued sequence spaces are estimated using information about the coordinate mappings. To do this some new ideas of combinatorial type are used. The results are applied to give sharp two‐sided estimates of the entropy numbers of some embeddings of Besov spaces. For instance, our main result allows us to give exact two‐sided estimates of the entropy numbers of the natural embedding of \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$B_{p_{1},\theta _{1}}^{\omega _{1}}(Q)$\end{document} in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$B_{p_{2},\theta _{2} }^{\omega _{2}}(Q),$\end{document} where Q = (0, 1)d; θ1, θ2, p1, p2 ∈ (0, ∞], when the condition 1/θ1 − 1/θ2 ≥ 1/p1 − 1/p2 > 0 is satisfied. This work enables us to construct an example showing that the behaviour under real interpolation of entropy numbers can be even worse than in the example of 7.
Multibrominated Hyperbranched Polymers: Synthesis and Further Functionalizations by ARGET ATRP or Click Chemistry
Authors: Popescu Delia‐Laura , Tsarevsky Nicolay V.
Published: April 2012

Hyperbranched polymers with multiple alkyl bromide peripheral groups were synthesized by the copolymerization of styrene with ethylene glycol dimethacrylate (2.5, 5.0, 7.5, or 10.0 mol% relative to styrene) in the presence of CBr4 (10–20‐fold excess vs. the radical initiator). The latter compound markedly delayed the gelation and served as the source of terminal bromine atoms via transfer to the propagating radicals. The degree of branching increased with the amount of crosslinker. The alkyl bromide groups were used in further chemical modifications (ATRP at low catalyst concentration or azidation with NaN3 followed by CuBr‐catalyzed click coupling of an alkyne‐terminated polymer) that yielded star copolymers with hyperbranched cores.
Tumour suppressor Fus1 provides a molecular link between inflammatory response and mitochondrial homeostasis
Authors: Uzhachenko Roman , Issaeva Natalia , Boyd Kelli , Ivanov Sergey V , Carbone David P , Ivanova Alla V
Published: April 2012

Fus1, encoded by a 3p21.3 tumour suppressor gene, is down‐regulated, mutated or lost in the majority of inflammatory thoracic malignancies. The mitochondrial localization of Fus1 stimulated us to investigate how Fus1 modulates inflammatory response and mitochondrial function in a mouse model of asbestos‐induced peritoneal inflammation. Asbestos treatment resulted in a decreased Fus1 expression in wild‐type (WT) peritoneal immune cells, suggesting that asbestos exposure may compromise the Fus1‐mediated inflammatory response. Untreated Fus1−/− mice had an ∼eight‐fold higher proportion of peritoneal granulocytes than Fus1+/+ mice, pointing at ongoing chronic inflammation. Fus1−/− mice exhibited a perturbed inflammatory response to asbestos, reflected in decreased immune organ weight and peritoneal fluid protein concentration, along with an increased proportion of peritoneal macrophages. Fus1−/− immune cells showed augmented asbestos‐induced activation of key inflammatory, anti‐oxidant and genotoxic stress response proteins ERK1/2, NFκB, SOD2, γH2AX, etc. Moreover, Fus1−/− mice demonstrated altered dynamics of pro‐ and anti‐inflammatory cytokine expression, such as IFNγ, TNFα, IL‐1A, IL‐1B and IL‐10. ‘Late’ response cytokine Ccl5 was persistently under‐expressed in Fus1−/− immune cells at both basal and asbestos‐activated states. We observed an asbestos‐related difference in the size of CD3+ CD4− CD8− DN T cell subset that was expanded four‐fold in Fus1−/− mice. Finally, we demonstrated Fus1‐dependent basal and asbestos‐induced changes in major mitochondrial parameters (ROS production, mitochondrial potential and UCP2 expression) in Fus1−/− immune cells and in Fus1‐depleted cancer cells, thus supporting our hypothesis that Fus1 establishes its immune‐ and tumour‐suppressive activities via regulation of mitochondrial homeostasis. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Coordinated expression of galectin‐3 and caveolin‐1 in thyroid cancer
Authors: Shankar Jay , Wiseman Sam M , Meng Fanrui , Kasaian Katayoon , Strugnell Scott , Mofid Alireza , Gown Allen , Jones Steven JM , Nabi Ivan R
Published: April 2012

Galectin‐3 (Gal3) is the single most accurate marker for the diagnosis of differentiated thyroid cancer (DTC). Gal3 overrides the tumour suppressor activity of caveolin‐1 (Cav1) and functions in concert with Cav1 to promote focal adhesion turnover and tumour cell migration and invasion. To study their coordinated role in progression of a human cancer, we investigated the expression of Gal3 and Cav1 in specimens of human benign thyroid lesions, DTC and anaplastic thyroid cancer (ATC). Gal3 and Cav1 expression is significantly associated with DTC and ATC, but not benign nodules. Essentially all Cav1‐positive DTC cancers express Gal3, supporting the synergistic activity of these two proteins in DTC progression. Similarly, coordinated elevated Gal3/Cav1 expression was observed in three DTC‐derived cell lines (papillary TCP1 and KTC1 and follicular FTC133) but only one (ACT1) of five ATC‐derived cell lines. Using siRNA knockdown, Gal3 and Cav1 were shown to be required for RhoA GTPase activation, stabilization of focal adhesion kinase (FAK; a measure of focal adhesion signalling and turnover) and increased migration of the DTC cell lines studied, but not the ATC cell lines, including ACT1, which expresses elevated levels of Gal3 and Cav1. Co‐expression of Gal3 and Cav1 in the T238 anaplastic cell line stabilized FAK‐GFP in focal adhesions. Gal3 and Cav1 therefore function synergistically to promote focal adhesion signalling, migration and progression of DTC. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Polyester composites of short pineapple fiber and glass fiber: Tensile and impact properties
Authors: Uma Devi L. , Bhagawan S.S. , Thomas S.
Published: April 2012

The tensile and impact performance of intimately mixed (IM) hybrid composites based on glass fiber (GF) and pineapple leaf fiber (PALF) was investigated. The composite was fabricated at constant volume fraction of fiber 0.3 Vf (fiber 0.3 and matrix 0.7). Keeping the volume fraction of matrix a constant (0.7 Vf), we have varied the PALF/GF ratio from 0 to 1. Incorporation of 0.1 volume fraction of GF increases the tensile strength of the hybrid composite by about 28%. The tensile strength showed a further increase when the volume fraction is changed to 0.7 and 0.9 Vf of GF. Intimately mixed hybrid composites exhibited higher impact strength than the individual fiber composites; the composite of PALF/GF ratio 70:30 showed maximum impact strength of 1203 J/m. A positive hybrid effect is observed for impact properties. Scanning electron micrographs of the fractured surfaces were examined to understand the fiber‐matrix adhesion. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Homogenized tensile and bending properties of plain weave single‐Ply E‐glass/epoxy
Authors: Karakaya Şükrü , Soykasap Ömer
Published: April 2012

This study empirically, numerically, and analytically analyzes the tensile and bending behavior of a plain weave single‐ply E‐glass/epoxy composite. In the empirical part of the study, tensile and simple bending experiments are conducted. Finite element method is used in the modeling part of the numerical study. Transverse and longitudinal fibers of the plain woven composite are modeled in one and three dimensions by using the ABAQUS software. Finally, mixture ratio approach and composite beam approach are considered in the analytical part of the study. Elastic modulus, Poisson's ratio, bending stiffness, and critical bending radius are obtained experimentally and are compared with the results of the finite element analyses and the results of the analytical study where applicable. The results closest to the empirically obtained ones are obtained by three‐dimensional (3D) finite elements analysis. Moreover, the mechanical characteristics obtained by the composite beam approach used in the analytical study are also very close to the values obtained by 3D finite elements analysis. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Crystal recovery from Al‐implantation induced damaging in 3C‐SiC films
Authors: Severino Andrea , Piluso Nicolò , Marino Antonio , La Via Francesco
Published: April 2012

Damaging in Al‐implanted 3C‐SiC and subsequent crystal recovery due to thermal treatments up to 1350 °C are evaluated by X‐ray diffraction and micro‐Raman spectroscopy. Reciprocal space mapping of (004) 3C‐SiC planes shows a low‐intensity implantation‐induced secondary peak at higher interplanar spacing in the as‐implanted 3C‐SiC sample, with a generated misfit between the implanted and the epitaxial region of about 0.6%. Increasing the annealing temperature from 950 °C to 1350 °C, the secondary peak is gradually re‐absorbed within the epitaxial 3C‐SiC reciprocal lattice point. Finally, the disappearance of the secondary peak after a 1350 °C thermal treatment is observed. Thus, implantation‐induced average strain, resulting in a severe 3C‐SiC deforma‐ tion, has been totally relieved at the highest annealing temperature. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural elucidation of phase I and II metabolites of bupivacaine in horse urine and fungi of the Cunninghamella species using liquid chromatography/multi‐stage mass spectrometry
Authors: Rydevik Axel , Bondesson Ulf , Hedeland Mikael
Published: April 2012

RATIONALE

Bupivacaine is a local anaesthetic prohibited in equine sports. It is highly metabolized in the horse but a thorough description of its metabolite profile is lacking. An administration study should find appropriate analytical targets for doping control. Furthermore, knowledge of an in vitro system for production of metabolites would be beneficial.

METHODS

Marcain® (bupivacaine hydrochloride) was administered subcutaneously to a horse and urine samples were collected. In vitro metabolic systems consisting of the fungi Cunninghamella elegans and Cunninghamella blakesleeana were incubated with bupivacaine and bupivacaine‐d9. Samples were analyzed directly after dilution or cleaned up using liquid‐liquid extraction. Separation was achieved with liquid chromatography. Mass spectrometric analysis was performed using positive electrospray ionization with both a tandem quadrupole and an ion trap instrument using MSn and hydrogen/deuterium exchange.

RESULTS

In horse urine, seven phase I metabolites were found: 3'‐ and 4'‐hydroxybupivacaine, N‐desbutylbupivacaine, two aliphatically hydroxylated metabolites, one N‐oxide, and dihydroxybupivacaine. Sulfated hydroxybupivacaine and glucuronides of 3'‐ and 4'‐hydroxybupivacaine and of dihydroxybupivacaine were also detected. All these metabolites were previously undescribed in the horse, except for 3'‐hydroxybupivacaine. 3'‐ and 4'‐Hydroxybupivacaine were designated as appropriate targets for doping control. Interestingly, all the equine phase I metabolites were also detected in the samples from C. elegans and C. blakesleeana.

CONCLUSIONS

The qualitative aspects of the metabolism of bupivacaine in the horse have been investigated with many novel metabolites described. The fungi C. elegans and C. blakesleeana have proven to be relevant models for mammalian metabolism of bupivacaine and they may in the future be used to produce analytical reference materials. Copyright © 2012 John Wiley & Sons, Ltd.
Feature‐based Type Identification of File Fragments
Authors: Amirani Mehdi Chehel , Toorani Mohsen , Mihandoost Sara
Published: April 2012

Digital information is packed into files when it is going to be stored on storage media. Each computer file is associated with a type. Type detection of computer data is a building block in different applications of computer forensics and security. Traditional methods were based on file extensions and metadata. The content‐based method is a newer approach with the lowest probability of being spoofed and is the only way for type detection of data packets and file fragments. In this paper, a content‐based method that deploys principle component analysis and neural networks for an automatic feature extraction is proposed. The extracted features are then applied to a classifier for the type detection. Our experiments show that the proposed method works very well for type detection of computer files when considering the whole content of a file. Its accuracy and speed is also significant for the case of file fragments, where data is captured from random starting points within files, but the accuracy differs according to the lengths of file fragments. Copyright © 2012 John Wiley & Sons, Ltd.
Surface topography effects in C60 bombardment of Si
Authors: Cook Edward L. , Krantzman Kristin D. , Garrison Barbara J.
Published: April 2012

Molecular dynamics simulations of multi‐impact bombardment of Si with 20‐keV C60 projectiles at normal incidence are performed for a total of 400 impacts, which corresponds to a fluence of of 7 × 1013 C60/cm2. The surface is roughened by successive bombardment and achieves a steady‐state root mean square roughness of 2.0 nm after about 100 impacts. There is a direct correlation between the local topography of the region around the impact point and the sputtered yield. The greatest yields of sputtered atoms are produced when the projectile impacts a mound, which is characterized by the height of the surface relative to the average surface height. When the projectile hits a local region corresponding to a crater with a height much less than the average surface height, the sputtered yield is very small. However, it is these trajectories that deposit carbon atoms at depths beneath the region from which atoms are sputtered, and are responsible for the buildup of carbon at the bottom of craters. Copyright © 2012 John Wiley & Sons, Ltd.
Electrical properties of polymer photovoltaic cells using pentacene‐doped PEDOT: PSS as a hole conducting layer
Authors: Kim Hyunsoo , Chandran Midhun , Park Sujin , Chae Hyunhee , Lee Jungrae , Choe Youngson
Published: April 2012

The performance characteristics of polymer photovoltaic cells, in which the pentacene‐doped PEDOT:PSS thin films are used as a hole conducting layer, have been investigated and characterized by employing AFM, SEM, UV‐visible, work function and current density‐voltage analysis. Pentacene‐doped PEDOT:PSS was prepared by blending pentacene with 1‐methy1‐2‐pyrrolidinone (NMP) and PEDOT:PSS in solution. By using NMP as a solvent, pentacene as a dopant was introduced into PEDOT:PSS films. The surface roughness of PEDOT:PSS films was increased, and aggregate boundaries were clearly distinguished. Pentacene might form aggregations with PEDOT:PSS during the film forming process. UV‐visible transmission intensity also increased as doping percent of pentacene increased. The work function of pentacene‐doped PEDOT:PSS film decreased by approximately 0.3 eV, and this may contribute to moving holes easily toward ITO substrate. Consequently, pentacene‐doped PEDOT:PSS film as a hole conducting layer leads to improving the performance characteristics of photovoltaic cells. Copyright © 2012 John Wiley & Sons, Ltd.
Evaluation of layered titanate nanosheets using TOF‐SIMS and G‐SIMS analysis
Authors: Mihara Ichiro , Nakagawa Keizo , Kudo Masahiro , Aoyagi Satoka
Published: April 2012

Nanostructure evaluation is crucial for developing highly controlled nanomaterials. The titanate nanosheets with a lamellar mesostructure synthesized using a lamellar self‐assembly of dodecanediamine (DDA) were evaluated with time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) and gentle‐SIMS (G‐SIMS) to evaluate detailed chemical structures which have not been provided with transmission electron microscopy (TEM), X‐ray diffraction, and ultraviolet–visible diffuse reflectance spectra analysis. Although TOF‐SIMS is a useful method for evaluating complex organic and inorganic materials, it is often difficult to interpret TOF‐SIMS spectra of complex samples due to complicated fragment ions. Therefore, G‐SIMS, helpful for analyzing intricate TOF‐SIMS spectra, was applied to extract important information of TOF‐SIMS data. For example, molecular ions and more intact fragment ions are emphasized and found easily using G‐SIMS. The layered titanate nanosheets sample produced using tetraisopropyl orthotitanate (TIPT), triethanolamine (TEOA), and DDA (TIPT + DDA + TEOA) and reference nanoparticle samples TIPT + DDA, TIPT + TEOA, and TIPT were prepared. As a result, titanate compounds and DDA molecular ions were only detected in TIPT + DDA + TEOA. Therefore, it is indicated that robust lamellar mesostructure of titanate compounds and DDA is produced by reactions related to TIPT, DDA, and TEOA. It is also suggested that organic metal materials which have large hydrocarbon groups can be analyzed using G‐SIMS. Copyright © 2012 John Wiley & Sons, Ltd.
Differential sputtering and the formation of repeating fragments in ToF‐SIMS spectra of light metal alloy surfaces
Authors: Nguyen Chuong L. , Metson James B.
Published: April 2012

Time of flight secondary ion mass spectrometry (ToF‐SIMS) spectra of aluminium hydroxide powders and thin films suggest that fragments of largely intact hydroxide layers are cleaved from the surface during ion bombardment. This leads to the presence of large repeating clusters of aluminium oxide dominated fragments up to 3000 Da in the SIMS spectra. The more intense repeating fragments of aluminium species appear to enhance the sputter rate on Al2O3. In the case of oxide films on the surface of aluminium alloy with 13 wt.% Si, there were no detectable higher mass repeating fragments for silicon species. The difference is linked both to the limited observations of these very large fragments in the absence of a layered crystal structure and the initially higher removal rate of aluminium species compared with silicon species on the surface of this alloy. This latter observation, confirmed by SIMS imaging during profiling, is at odds with typical observations reported in the literature. Copyright © 2012 John Wiley & Sons, Ltd.
Nanocrystalline ZnS thin films by chemical bath deposition method and its characterization
Authors: Salim S. M. , Eid A. H. , Salem A. M. , Abou El‐khair H. M.
Published: April 2012

Zinc sulfide is a wide band gap semiconductor with a range of potential applications in optoelectronic devices. ZnS nanocrystalline thin films are prepared by chemical bath deposition on glass substrates. The chemical bath is an aqueous solution of zinc chloride, thiourea, ammonia and hydrazine. Governing factors related to the growth condition were the concentration of precursor solution, growth temperature, concentration of aqueous ammonia and growth duration. The structural and the surface topography of ZnS films have been investigated by x‐ray diffraction and scanning electron microscope. The effect of annealing is studied. The x‐ray diffraction study reveals that both powder and thin films are polycrystalline in nature and have a composition corresponding to the cubic structure [β‐ZnS]. The films are very close to ZnS stoichiometry and no organic compounds, Zn(OH)2 or ZnO species were observed as impurities. As it is also revealed from x‐ray diffraction analysis, the average size of these nanocrystallites is about 3 nm using Scherrer formula. SEM characterization shows that the sample surface consisted of small uniform grains and was free from pinholes. Obviously, it is evident that aggregation of grains on the substrate forms the thin film. The films showed a high transmission and a wide band gap of 3.83 eV. This value is larger than the typical value of the bulk ZnS (~3.6 eV), probably due to the quantum size effect as expected for the nanocrystalline nature of the films. The wide band gap of these films makes it possible to use them as window layer for solar cells. Copyright © 2012 John Wiley & Sons, Ltd.
The enumeration of chemical space
Authors: Reymond Jean‐Louis , Ruddigkeit Lars , Blum Lorenz , van Deursen Ruud
Published: April 2012

In the field of medicinal chemistry, the chemical space describes the ensemble of all organic molecules to be considered when searching for new drugs (estimated >1060 molecules), as well as the property spaces in which these molecules are placed for the sake of describing them. Molecules can be enumerated computationally by the millions, which was first undertaken in the field of computer‐aided structure elucidation. Scoring the enumerated virtual libraries by virtual screening has recently become an attractive strategy to prioritize compounds for synthesis and testing. Enumeration methods include combinatorial linking of fragments, genetic algorithms based on cycles of enumeration and selection by ligand‐based or target‐based scoring functions, and exhaustive enumeration from first principles. The chemical space of molecules following simple rules of chemical stability and synthetic feasibility has been enumerated up to 13 atoms of C, N, O, Cl, S, forming the GDB‐13 database with 977 million structures. The database has been organized in a 42‐dimensional chemical space using molecular quantum numbers (MQN) as descriptors, which can be visualized by projection in two dimensions by principal component analysis, and searched within seconds using a Web browser available at www.gdb.unibe.ch. © 2012 John Wiley & Sons, Ltd.

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Computer and Information Science > Chemoinformatics
Cerebrospinal fluid amyloid-β 2-42 is decreased in Alzheimer’s, but not in frontotemporal dementia
Authors: Bibl Mirko , Gallus Marion , Welge Volker , Esselmann Hermann , Wolf Stefanie , Rüther Eckart , Wiltfang Jens
Published: April 2012

Alzheimer’s dementia (AD) and frontotemporal dementias (FTD) are common and their clinical differential diagnosis may be complicated by overlapping symptoms, which is why biomarkers may have an important role to play. Cerebrospinal fluids (CSF) Aβ2-42 and 1-42 have been shown to be similarly decreased in AD, but 1-42 did not display sufficient specificity for exclusion of other dementias from AD. The objective of the present study was to clarify the diagnostic value of Aβ2-42 peptides for the differential diagnosis of AD from FTD. For this purpose, 20 non-demented disease controls (NDC), 22 patients with AD and 17 with FTD were comparatively analysed by a novel sequential aminoterminally and carboxyterminally specific immunoprecipitation protocol with subsequent Aβ-SDS-PAGE/immunoblot, allowing the quantification of peptides 1-38ox, 2-40 and 2-42 along with Aβ 1-37, 1-38, 1-39, 1-40, 1-40ox and 1-42. CSF Aβ1-42 was decreased in AD as compared to NDC, but not to FTD. In a subgroup of the patients analyzed, the decrease of Abeta2-42 in AD was evident as compared to both NDC and FTD. Aβ1-38 was decreased in FTD as compared to NDC and AD. For differentiating AD from FTD, Aβ1-42 demonstrated sufficient diagnostic accuracies only when combined with Aβ1-38. Aβ2-42 yielded diagnostic accuracies of over 85 % as a single marker. These accuracy figures could be improved by combining Aβ2-42 to Aβ1-38. Aβ2-42 seems to be a promising biomarker for differentiating AD from other degenerative dementias, such as FTD.
Cell surface associated glycohydrolases in normal and Gaucher disease fibroblasts
Authors: Aureli Massimo , Bassi Rosaria , Loberto Nicoletta , Regis Stefano , Prinetti Alessandro , Chigorno Vanna , Aerts Johannes M. , Boot Rolf G. , Filocamo Mirella , Sonnino Sandro
Published: April 2012

Gaucher disease (GD) is the most common lysosomal disorder and is caused by an inherited autosomal recessive deficiency in β‐glucocerebrosidase. This enzyme, like other glycohydrolases involved in glycosphingolipid (GSL) metabolism, is present in both plasma membrane (PM) and intracellular fractions. We analyzed the activities of CBE‐sensitive β‐glucosidase (GBA1) and AMP‐DNM‐sensitive β‐glucosidase (GBA2) in total cell lysates and PM of human fibroblast cell lines from control (normal) subjects and from patients with GD clinical types 1, 2, and 3. GBA1 activities in both total lysate and PM of GD fibroblasts were low, and their relative percentages were similar to those of control cells. In contrast, GBA2 activities were higher in GD cells than in control cells, and the degree of increase differed among the three GD types. The increase of GBA2 enzyme activity was correlated with increased expression of GBA2 protein as evaluated by QRT‐PCR. Activities of β‐galactosidase and β‐hexosaminidase in PM were significantly higher for GD cells than for control cells and also showed significant differences among the three GD types, suggesting the occurrence of cross‐talk among the enzymes involved in GSL metabolism. Our findings indicate that the profiles of glycohydrolase activities in PM may provide a valuable tool to refine the classification of GD into distinct clinical types.
Pathology supported genetic testing and treatment of cardiovascular disease in middle age for prevention of Alzheimer’s disease
Authors: Kotze Maritha J. , van Rensburg Susan J.
Published: April 2012

Chronic, multi-factorial conditions caused by a complex interaction between genetic and environmental risk factors frequently share common disease mechanisms, as evidenced by an overlap between genetic risk factors for cardiovascular disease (CVD) and Alzheimer’s disease (AD). Single nucleotide polymorphisms (SNPs) in several genes including ApoE, MTHFR, HFE and FTO are known to increase the risk of both conditions. The E4 allele of the ApoE polymorphism is the most extensively studied risk factor for AD and increases the risk of coronary heart disease by approximately 40 %. It furthermore displays differential therapeutic responses with use of cholesterol-lowering statins and acetylcholinesterase inhibitors, which may also be due to variation in the CYP2D6 gene in some patients. Disease expression may be triggered by gene-environment interaction causing conversion of minor metabolic abnormalities into major brain disease due to cumulative risk. A growing body of evidence supports the assessment and treatment of CVD risk factors in midlife as a preventable cause of cognitive decline, morbidity and mortality in old age. In this review, the concept of pathology supported genetic testing (PSGT) for CVD is described in this context. PSGT combines DNA testing with biochemical measurements to determine gene expression and to monitor response to treatment. The aim is to diagnose treatable disease subtypes of complex disorders, facilitate prevention of cumulative risk and formulate intervention strategies guided from the genetic background. CVD provides a model to address the lifestyle link in most chronic diseases with a genetic component. Similar preventative measures would apply for optimisation of heart and brain health.
Screws versus hooks: Implant cost and deformity correction in adolescent idiopathic scoliosis
Authors: Jaquith Bradley P. , Chase Adam , Flinn Phillip , Sawyer Jeffrey R. , Warner William C. , Freeman Barney L. , Kelly Derek M.
Published: April 2012

Objective

To compare the costs of two spinal implants—hook and hybrid constructs and pedicle screw constructs—in posterior spinal fusion for adolescent idiopathic scoliosis (AIS) as they relate to intraoperative deformity correction.

Study design and method

This retrospective study examined 50 patients with AIS who were treated with posterior spinal fusion using segmental hook-hybrid constructs (23) or pedicle screws (27). Radiographic parameters measured on immediate preoperative and initial standing postoperative scoliosis films were the coronal Cobb angles of the upper thoracic, middle thoracic, lumbar, and instrumented curves; global coronal and sagittal balance; thoracic kyphosis; lumbar lordosis; and type and number of implants used. Current implant cost data were obtained from three major spinal implant manufacturers to determine the total cost of the constructs, cost per degree of correction, cost per level fused, and cost per degree of correction of the major curve.

Results

After surgery, the average percentage of correction for the middle thoracic curve or major curve was 57 % in the hook-hybrid group compared to 73 % in the pedicle screw group ( P < 0.001). The average amount of correction of the major curve was 31.1° in the hook-hybrid group compared to 42.7° in the pedicle screw group ( P < 0.001). The average number of fused levels was 10.7 in the hook-hybrid group compared to 12.2 in the pedicle screw group ( P < 0.001). The average number of implants was 14.8 in the hook-hybrid group compared to 23.3 in the pedicle screw group ( P < 0.001). The average total cost of implants was $11,248 in the hook-hybrid group compared to $22,826 in the pedicle screw group ( P < 0.001), and the average cost per fused level was $1,058 in the hook-hybrid group compared to $1,878 in the pedicle screw group ( P < 0.001). The average cost per degree of correction of the major curve was $415 in the hook-hybrid group compared to $559 in the pedicle screw group ( P = 0.0014). The global coronal balance, global sagittal balance, thoracic kyphosis, and lumbar lordosis did not differ significantly between the two groups.

Conclusion

Pedicle screw instrumentation was shown to be more expensive overall, per fused level, and per degree of correction. Also, more implants were used and more levels were fused in the pedicle screw group than in the hook-hybrid group. Pedicle screws showed a statistically significantly greater percentage of correction of the major curve. Physicians must evaluate each patient individually and determine if the increased percentage of correction warrants the increased cost for pedicle screw constructs.
MiR‐26 controls LXR‐dependent cholesterol efflux by targeting ABCA1 and ARL7
Authors: Sun Dongsheng , Zhang Jun , Xie Jianhong , Wei Wei , Chen Mantao , Zhao Xiang
Published: April 2012

Cellular cholesterol levels are tightly regulated and represent a balance of cholesterol uptake, endogenous synthesis and efflux. Although the classic transcriptional regulations of cholesterol metabolism by liver X receptors (LXRs) have been well studied, the potential effects of LXR‐responsive microRNAs (miRNAs) still need to be unveiled. Here, we describe that miR‐26, an LXR‐suppressed miRNA, inhibits the expression of the ATP‐binding cassette transporter A1 (ABCA1) and ADP‐ribosylation factor‐like 7 (ARL7), two LXR target genes which play critical roles in cholesterol efflux. These findings have not only figured out an alternative mechanism for LXR regulation, but also provided a potential therapeutic target for cholesterol metabolic disorders.
The murine Gcap14 gene encodes a novel microtubule binding and bundling protein
Authors: Hosono Hitomi , Yamaguchi Nao , Oshima Kenzi , Matsuda Tsukasa , Nadano Daita
Published: April 2012

Gcap14
physically interacts with
Gcap14
by anti tag coimmunoprecipitation (View Interaction: 1, 2)
Survival hydrodynamics
Authors: Triantafyllou M. S.
Published: April 2012

Fish escaping from predators exhibit amazing acceleration. The hydrodynamic mechanisms employed to power this acceleration are highlighted in the paper by Gazzola, van Rees & Koumoutsakos (J. Fluid Mech., this issue, vol. 698, 2012, pp. 5–17), showing that the fish bends its entire body and caudal fin, in order to entrap and then accelerate as large a mass of water as possible. It is also shown that hydrodynamic optimization drives the fast-start kinematics.
Sources of Gains in Corporate Mergers: Refined Tests from a Neglected Industry
Authors: Becher David A. , Mulherin J. Harold , Walkling Ralph A.
Published: April 2012

Our work provides refined tests of the source of merger gains in a neglected industry: utilities. Utilities offer fertile ground for analysis of traditional theories: synergy, collusion, hubris, and anticipation. Utility mergers create wealth for the combined firm, consistent with both the synergy and collusion hypotheses. To distinguish between these hypotheses, we study rival stock returns across dimensions related to collusion: deregulation, geography, and horizontal and withdrawn deals. We also find that the impact of mergers on consumer prices is consistent with synergy rather than collusion. Analysis of industry rivals that become targets also rejects collusion and is consistent with anticipation.
The Fiscal Compact and the European Constitutions: ‘Europe Speaking German’
Authors: LB  , JHR
Published: April 2012

In between the writing of this editorial and the publication of this issue of EuConst, the Treaty on Stability, Coordination and Governance in the Economic and Monetary Union, in everyday parlance the ‘Fiscal Compact’, will have been signed by the representatives of the governments of the contracting parties — the member states of the European Union minus the United Kingdom and the Czech Republic. The Fiscal Compact is intended to foster budgetary discipline, to strengthen the coordination of economic policies and to improve the governance of the euro area.
Milestones of Normal Development in Early Years (MONDEY)
Authors: Pauen Sabina , Heilig Lena , Danner Daniel , Haffner Johann , Tettenborn Andrea , Roos Jeanette
Published: April 2012

Standardisierte Instrumente zur Dokumentation der frühkindlichen Entwicklung für den Altersbereich 0 – 3 Jahre liegen im deutschen Sprachraum kaum vor. Der vorliegende Beitrag diskutiert zunächst Anforderungen an geeignete Verfahren und stellt anschließend ein neues Dokumentationsprogramm (MONDEY; Pauen, 2011 ) vor. MONDEY enthält Beschreibungen von 111 Meilensteinen, die acht unterschiedlichen Entwicklungsbereichen (Gob- und Feinmotorik, Wahrnehmung und Denken, Sprache, Soziale Beziehungen, Selbstregulation, Emotionen) zugeordnet sind, welche ihrerseits die allgemeine Entwicklung in der frühen Kindheit widerspiegeln sollen. Strukturgleichungsmodelle, die mit einer Pilotversion des Instrumentes ( Pauen, 2008 ) durchgeführt wurden, bestätigen die hierarchische Konzeption von MONDEY und dokumentieren eine überraschend gute Modellanpassung. Der allgemeine Entwicklungswert korreliert zudem hoch mit dem Alter der Kinder. Auf dieser Grundlage schließen wir, dass das neue Programm eine hohe Konstruktvalidität aufweist.
Handlungskompetenzen im Prozess der Beobachtung mit zwei unterschiedlichen Beobachtungsverfahren
Authors: Wildgruber Andreas
Published: April 2012

Die Beobachtung kindlicher Bildungs- und Entwicklungsprozesse hat zentrale Funktion für das pädagogische Handeln. Dieser Artikel präsentiert Ergebnisse einer qualitativ-interpretativen Untersuchung, die der Frage nachgeht, welche Kompetenzen das Handeln pädagogischer Fachkräfte im Beobachtungsprozess leiten. Im Anschluss an Erpenbeck und Rosenstiel (2003) wurde implizites Wissen als zentrales Element von Handlungskompetenz angesehen und unter Anwendung der Dokumentarischen Methode rekonstruiert. Dazu wurde untersucht, wie Erzieherinnen Beobachtungen mit den Methoden „Bildungs- und Lerngeschichten“ resp. der „Entwicklungstabelle“ von Beller & Beller (2006) auswerten und welche Schlussfolgerungen für die Unterstützung kindlicher Bildungsprozesse sie ziehen. Es ließen sich keine verfahrensübergreifend einheitlichen Orientierungen „kompetenten“ Beobachtungshandelns heraus arbeiten. Statt dessen zeigten sich vier Kompetenzdimensionen. Die Darstellung der Ergebnisse fokussiert auf die Kompetenzdimensionen, die Erzieherinnen mit unterschiedlicher Berufs- und Weiterbildungserfahrung zeigen und legt Schlüsse hinsichtlich notwendiger Kompetenzen nahe. „Beobachtungskompetenz“ erweist sich als Kompetenz zum reflexiven und selbstorganisierten Handeln hinsichtlich dieser Dimensionen.
Earthquake spectra and near‐source attenuation in the Cascadia subduction zone
Authors: Gomberg J. , Creager K. , Sweet J. , Vidale J. , Ghosh A. , Hotovec A.
Published: April 2012

Models of seismic source displacement spectra are flat from zero to some corner frequency, fc, regardless of source type. At higher frequencies spectral models decay as f−1 for slow events and as f−2 for fast earthquakes. We show that at least in Cascadia, wave propagation effects likely control spectral decay rates above ∼2 Hz. We use seismograms from multiple small‐aperture arrays to estimate the spectral decay rates of near‐source spectra of 37 small ‘events’ and find strong correlation between source location and decay rate. The decay rates (1) vary overall by an amount in excess of that inferred to distinguish slow sources from fast earthquakes, (2) are indistinguishable for sources separated by a few tens of km or less, and (3) separate into two populations that correlate with propagation through and outside a low‐velocity zone imaged tomographically. We find that some events repeat, as is characteristic of low‐frequency earthquakes (LFEs), but have spectra similar to those of non‐repeating earthquakes. We also find no correlation between spectral decay rates and rates of ambient tremor activity. These results suggest that earthquakes near the plate boundary, at least in Cascadia, do not distinctly separate into ‘slow’ and ‘fast’ classes, and correctly accounting for propagation effects is necessary to characterize sources.
Effect of Scirpus mariqueter on nitrous oxide emissions from a subtropical monsoon estuarine wetland
Authors: Yu Zhongjie , Li Yangjie , Deng Huanguang , Wang Dongqi , Chen Zhenlou , Xu Shiyuan
Published: April 2012

The effects of the wetland plant Scirpus mariqueter on nitrous oxide (N2O) emissions in Yangtze estuary, China, were investigated using an in situ static chamber technique. Field measurements spanned the entire growing season (May to October) and encompassed a wide range of weather conditions typical of the subtropical monsoon climate of this region. Simultaneous measurement of carbon dioxide (CO2) and anatomical measurements were conducted to experimentally determine the gas transport mechanisms of S. mariqueter on N2O flux. S. mariqueter had a significant effect on N2O flux. Based on the comparison of light‐dark and clipped‐unclipped gas flux, N2O flux was negatively correlated with NEE (p < 0.0001) and NPP (p < 0.001) under light conditions when S. mariqueter was present but positively with temperatures in the dark condition or when S. mariqueter was clipped. Besides the plant uptake corresponding to the N2O negative flux in light chamber, it is reasonable to assume that because of the limitation of nitrate in sediment, coupled nitrification‐denitrification is the main process of N2O producing. O2 transported into the S. mariqueter rhizosphere during photosynthesis stimulated denitrifier also would consume the N2O and would be induced to the N2O diffusing from atmosphere into sediment. Although photosynthetic activity of S. mariqueter attenuated N2O flux significantly over the course of the entire study period, creating a net sink for atmospheric N2O under light condition, the marsh of Chongming Island Dongtan wetland was a net source of atmospheric N2O during the active S. mariqueter growth phase (averaged flux was 98.3 μg N2O m−2 h−1).
Impact of wildfire on the thermal behavior of northern peatlands: Observations and model simulations
Authors: Kettridge N. , Thompson D. K. , Waddington J. M.
Published: April 2012

Wildfire represents the single largest disturbance to the ecohydrological function of northern peatlands. Alterations to peatland thermal behavior as a result of wildfire will modify the carbon balance of these important long‐term global carbon stores and regulate post‐fire ecosystem recovery. We simulate the 3‐D thermal behavior of a peatland that has been disturbed by wildfire to identify how changes in peat temperatures emerge from changes to the surface energy balance and peat thermal properties. Peat temperatures are simulated within two adjacent peatlands, one area having burned 4 years previously, the second which has been wildfire‐free for 75 years. We demonstrate that there is only a small alteration to the thermal response inSphagnum fuscum hummocks that are not severely burnt within the wildfire. In contrast, wildfire produces important changes to the energy balance of Sphagnumhollows. A large reduction in the latent heat flux post‐fire increases surface temperatures by up to 30°C during daytime summer conditions. However, temperatures through the peat profile are insensitive to these increases in surface temperature. The low surface moisture content of near‐surface peat insulates the profile from these higher temperatures and, at depths below 0.015 m, only small differences are identifiable between burned and unburned hollow temperatures. Nevertheless, we argue that these alterations to near‐surface temperatures and evaporation rates likely substantially influence the thermal and hydrological conditions post‐wildfire, impacting the peatland recovery.