bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of imputation methods for interval censored time‐to‐event data in joint modelling of tree growth and mortality
Authors: Lee Terry C. K. , Zeng Leilei , Thompson Darby J. S. , Dean C. B. 
Published: July 2011

AbstractThe authors link time‐to‐event models with longitudinal models through shared latent variables when the time of the event of interest is known only to lie within an interval. The context of tree growth and mortality studies presents a natural application of shared parameter joint modelling where a latent feature of each tree impacts both mortality and growth. The authors' developments are motivated by such an application, with the additional caveat that event‐times are not known exactly, since the trees are subject to intermittent observation, with the time between measurements extending into decades or longer. Such interval censoring is a common occurrence in similar long‐term experiments in resource management, ecology and health research. The additional numerical complexity resulting from interval censored time‐to‐event data often makes inference for joint models prohibitive. The authors examine properties of three event‐time imputation methods that enable application of now standard joint modelling techniques to interval censored time‐to‐event data. The imputation techniques include the midpoint method, a kernel smoothing method, and a backsolve method which incorporates information from the longitudinal trajectory. Joint analysis of a designed, long‐term, forestry experiment is presented, accompanied by a simulation study investigating the properties of the three event‐time imputation techniques. The Canadian Journal of Statistics 39: 438–457; 2011 © 2011 Statistical Society of Canada
No Impact of Atrial Fibrillation on Mortality Risk in Optimally Treated Heart Failure Patients
Authors: Tveit Arnljot , Flonaes Berit , Aaser Ellinor , Korneliussen Kari , Froland Gisle , Gullestad Lars , Grundtvig Morten 
Published: July 2011

AbstractBackground:Several studies have shown that atrial fibrillation (AF) is associated with increased risk of death in heart failure (HF) patients. However, it is not clear whether this increased risk is independent of other risk factors.Hypothesis:We hypothesized that AF would be an independent risk factor for death in a large cohort of HF patients.Methods:Patients referred to Norwegian HF outpatient clinics were enrolled between October 2000 and February 2008. Patients with heart rhythm other than AF or sinus rhythm were excluded. Mortality data were obtained from the National Statistics Bureau, Statistics Norway with the last update February 2008.Results:There were 4048 patients included in the analysis, with a median follow‐up of 28 months. Adherence to guidelines regarding medical treatment was high. In univariate analysis, AF patients (n = 1391) had a higher risk of death than patients in sinus rhythm (n = 2657) (hazard ratio [HR] 1.181; 95% confidence interval (CI), 1.044–1.336; P = 0.008). However, after adjusting for confounding factors (age, New York Heart Association class, coronary artery disease as the main cause of HF, use of any loop diuretic, hemoglobin level, and serum creatinine), AF was no longer associated with increased risk of death (HR 1.037; 95% CI, 0.901–1.193; P = 0.619).Conclusions:In this cohort of heart failure patients receiving optimal medical treatment at specialized HF clinics, AF was not associated with increased risk of death after adjusting for confounding factors. © 2011 Wiley Periodicals, Inc.AstraZeneca Norway provided secretarial assistance in maintaining the Norwegian heart failure registry by financing an independent IT consultant. The authors have received research grants, consultancy fees, and/or honoraria for lectures from several pharmaceutical companies. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
Synthesis and Anticancer Activity of the (R,S)‐Benzofused 1,5‐Oxathiepine Moiety Tethered to Purines through Alkylidenoxy Linkers
Authors: Kimatrai María , Conejo‐García Ana , Ramírez Alberto , Andreolli Elena , Da Silveira‐Gomes Adriane , García María Angel , Aránega Antonia , Marchal Juan A. , Campos Joaquín M. 
Published: July 2011

AbstractHerein we report the design, synthesis, and anticancer activity of a series of substituted (R,S)‐9‐[2‐ or 3‐(3,4‐dihydro‐2H‐1,5‐benzoxathiepine‐3‐yloxy)alkyl]‐9H‐purines. Derivatives with propylenoxy‐linked 2′,6′‐dichloro‐ and 6′‐bromopurines are more active than their respective ethylenoxy‐linked purine conjugates. On the other hand, the compound with a propylenoxy‐linked 6′‐chloropurine is nearly equipotent to the corresponding ethylenoxy‐linked conjugate. Our results show that bromo‐ and chloropurine‐conjugated benzoxathiepines containing a propylenoxy linker are able to inhibit PI3 kinase (PI3K) phosphorylation in MCF‐7 breast cancer cells, indicating that the activation of eIF2α, together with inhibition of the PI3K pathway, is the mechanism of action by which these compounds effect their antitumor activity in the MCF‐7 cell line; apoptosis was induced in a p53‐independent manner.
Borane Derivatives: A New Class of Super‐ and Hyperhalogens
Authors: Pathak Biswarup , Samanta Devleena , Ahuja Rajeev , Jena Purusottam 
Published: July 2011

AbstractSuper‐ and hyperhalogens are a class of highly electronegative species whose electron affinities far exceed those of halogen atoms and are important to the chemical industry as oxidizing agents, biocatalysts, and building blocks of salts. Using the well‐known Wade–Mingos rule for describing the stability of closo‐boranes BnHn2− and state‐of‐the‐art theoretical methods, we show that a new class of super‐ and hyperhalogens, guided by this rule, can be formed by tailoring the size and composition of borane derivatives. Unlike conventional superhalogens, in which a central metal atom is surrounded by halogen atoms, the superhalogens formed according to the Wade–Mingos rule do not have to have either halogen or metal atoms. We demonstrate this by using B12H13 and its isoelectronic cluster CB11H12 as examples. We also show that while conventional superhalogens containing alkali atoms require at least two halogen atoms, a single borane‐like moiety is sufficient to give M(B12H12) clusters (M=Li, Na, K, Rb, Cs) superhalogen properties. In addition, hyperhalogens can be formed by using the above superhalogens as building blocks. Examples include M(B12H13)2 and M(CB11H12)2 (M=Li–Cs). This finding opens the door to an untapped source of superhalogens and weakly coordinating anions with potential applications.
Deep ultraviolet mapping of intracellular protein and nucleic acid in femtograms per pixel
Authors: Cheung Man C. , Evans James G. , McKenna Brian , Ehrlich Daniel J. 
Published: July 2011

AbstractBy using imaging spectrophotometry with paired images in the 200‐ to 280‐nm wavelength range, we have directly mapped intracellular nucleic acid and protein distributions across a population of Chinese hamster ovary (CHO‐K1) cells. A broadband 100× objective with a numerical aperture of 1.2 NA (glycerin immersion) and a novel laser‐induced‐plasma point source generated high‐contrast images with short (∼100 ms) exposures and a lateral resolution nearing 200 nm that easily resolves internal organelles. In a population of 420 CHO‐K1 cells and 477 nuclei, we found a G1 whole‐cell nucleic acid peak at 26.6 pg, a nuclear‐isolated total nucleic acid peak at 11.4 pg, and, as inferred by RNase treatment, a G1 total DNA mass of 7.4 pg. At the G1 peak, we found a whole‐cell protein mass of 95.6 pg, and a nuclear‐isolated protein mass of 39.3 pg. An algorithm for protein quantification that senses peptide‐bond (220‐nm) absorbance was found to have a higher signal‐to‐noise ratio and to provide more reliable nucleic acid and protein determinations when compared to more classical 280/260‐nm algorithms when used for intracellular mass mapping. Using simultaneous imaging with common nuclear stains (Hoechst 33342, Syto‐14, and Sytox Orange), we have compared staining patterns to deep‐UV images of condensed chromatin and have confirmed bias of these common nuclear stains related to nuclear packaging. The approach allows absolute mass measurements with no special sample preparation or staining. It can be used in conjunction with normal fluorescence microscopy and with relatively modest modification of the microscope. © 2011 International Society for Advancement of Cytometry
A cascading failure model for interdomain routing system
Authors: Guo Yi , Wang Zhenxing , Luo Shaopeng , Wang Yu 
Published: July 2011

SUMMARYThere have been many researches on border gateway protocol (BGP) security, most of which mainly focused on how to enhance the security of the BGP protocol or the interdomain routing system. However, few works studied the vulnerabilities especially the production mechanism of security events in the interdomain routing system. It takes many obstacles to understand and improve the security of the interdomain routing system. This paper explores the cascading failure phenomenon of the interdomain routing system. First, we devise a state machine to describe the state transition of BGP nodes and then give a detailed analysis of the BGP failure. Second, on the basis of the preferential attachment characteristic, we propose a cascading failure model for the interdomain routing system, which depicts the production mechanism of cascading failure, and introduce two evaluating indicators, the proportion of failed nodes and the proportion of failed links, to assess the scale of cascading failure. Furthermore, we apply the cascading failure model to display two different cascading failure scenes. The experimental results show that random failure has less influence on the interdomain routing system, while its robustness against hostile attack is weak. Copyright ©2011 John Wiley & Sons, Ltd.
Drug development and research in New Zealand: policies affecting the industry
Authors: Lockhart Michelle Marie , Babar Zaheer‐Ud‐Din , Garg Sanjay 
Published: July 2011

AbstractMany countries employ a range of policies to support their drug development industry. The support is primarily because of the perceived potential benefits from wealth creation, employment, and international trade related to a high‐technology industry. New Zealand (NZ) has a growing drug development industry; this article reports on the results of interviews with people representing the industry. The NZ industry reported that government policies that included funding of scientific, medical, and drug development research, a robust regulatory system, and strong patent laws have created a cluster of expertise for specialized drug development services. This is similar to those that have been reported to encourage the biotechnology industries of many countries. Threats to the industry in NZ include insufficient funding, small industry size, insufficient supportive policies, and stakeholders' lack of understanding of the industry. These barriers differ from those of developing countries such as China and India, probably because NZ's industry is built on its scientific and medical research rather than its manufacturing capability. The specific policies requested to further support the NZ industry include increased government investment, improved management of funding, and support for research, education, and career development. Drug Dev Res 73: 1–10, 2012. © 2011 Wiley Periodicals, Inc.
Synergism between tramadol and meloxicam in the formalin test involves both opioidergic and serotonergic pathways
Authors: Isiordia‐Espinoza Mario A. , Terán‐Rosales Flavio , Reyes‐García Gerardo , Granados‐Soto Vinicio 
Published: July 2011

AbstractThis study was designed to evaluate the antinociceptive interaction of the tramadol–meloxicam combination in different proportions (tramadol + meloxicam in 1:1, 1:3, and 3:1 ratios), as well as the role of nitric oxide, opioidergic, and serotonergic pathways in the antinociceptive effect of the combination. The effects of individual drugs and fixed‐ratio combinations were assayed using the 3% formalin test in mice. Isobolographic analysis was employed to characterize the synergism produced by the combinations. Tramadol (3.16–10 mg/kg, i.m.), meloxicam (3.16–17.8 mg/kg, i.m.), and tramadol–meloxicam combinations produced a dose‐dependent antinociceptive effect. ED30 values were estimated for the individual drugs, and isobolograms were constructed. The tramadol + meloxicam 1:1 and 1:3 ratio combinations showed synergistic interactions while the 3:1 ratio produced additive effects. Naloxone (1 mg/kg, i.m.) or methiothepin (0.1 mg/kg, i.m.), but not L‐NAME (3 mg/kg, i.m.), prevented the antinociceptive effects of the combination. These data suggest that (1) the tramadol–meloxicam combination produces a functional synergistic interaction that involves both opioid and serotonin receptors, and (2) this combination may be a promising tool in pain management. Drug Dev Res 73: 43–50, 2012. © 2011 Wiley Periodicals, Inc.
Comparing surface effective saturation and depth‐to‐water‐level as predictors of plant composition in a restored riparian wetland
Authors: Booth Eric G. , Loheide Steven P. 
Published: July 2011

ABSTRACTDepth‐to‐water‐level (DTWL) measurements in shallow groundwater piezometers are commonly used to develop predictive relationships between wetland plant composition and the water regime. These analyses, however, implicitly use DTWL as a surrogate for the soil water regime within the root zone. We collected bi‐weekly field measurements of DTWL and surface effective saturation (SES) at a riparian wetland (3–4 years after restoration) in southwestern Wisconsin during the 2009 and 2010 growing seasons. Plant species composition was also sampled at the same locations (N = 62). Nonmetric multidimensional scaling (NMS) and nonparametric multiplicative regression (NPMR) were used to compare how effectively the two hydrological metrics explain the overall plant community ordination space (NMS) and predict the probability of presence of certain dominant species (NPMR). In addition, we performed each statistical method on each year's data separately in order to estimate the robustness of the metrics to predict species composition. Both SES and DTWL metrics were significantly correlated with one NMS axis for both years, although correlations were higher and more significant (p < 0·001) with the SES metrics. NPMR‐generated models were created for six representative species using the SES and DTWL metrics as predictor variables. Models created using the SES metrics had consistently higher evaluation metrics for both years as compared with the DTWL metrics. While the metrics that consistently led to models with the highest evaluation metric (logβ > 2·2) for each of the species were mean and minimum SES, models that used mean SES were more temporally consistent and, therefore, more generally applicable. Copyright © 2011 John Wiley & Sons, Ltd.
Cationic Boron‐Centred Hexanuclear Zirconium Cluster Compounds with Nitrilo Ligands and [MIIICl4]– Counter Ions: [(Zr6B)Cl12(CH3CN)6][MIIICl4] with MIII = Al, Ga, In
Authors: Bernsdorf Arne , Köckerling Martin 
Published: July 2011

AbstractMolecular zirconium cluster ions were excised from the solid‐state precursor K2[(Zr6B)Cl15] using acetonitrile as the solvent. With the addition of the Lewis acids AlCl3, GaCl3 or InCl3 the chemical equilibria between the different cluster species in solution of the type [(Zr6B)Cli12(CH3CN)6–xClax]1–x with 0 ≤ x ≤ 6 are shifted such that only one species is present, with x = 0, i.e. [(Zr6B)Cli12(CH3CN)6]+. This was confirmed by 11B NMR spectroscopy. From the corresponding solutions four crystalline compounds were obtained, [(Zr6B)Cl12(CH3CN)6][AlCl4] (1), [(Zr6B)Cl12(CH3CN)6][AlCl4]·CH3CN (2), [(Zr6B)Cl12(CH3CN)6][GaCl4]·CH3CN (3) or [(Zr6B)Cl12(CH3CN)6][InCl4] (4). The single‐crystal X‐ray structures of 1–3 were determined. They all crystallize in the space group P$\bar {1}$ with two formula units per unit cell with the following cell parameters: 1: a = 12.1012(4), b = 12.7463(4), c = 17.2155(5) Å, α = 111.847(2), β = 90.243(2), γ = 117.263(2)°; 2: a = 12.037(5), b = 12.787(5), c = 17.675(7) Å, α = 92.63(1), β = 109.57(1), γ = 116.01(1)°; 3: a = 12.0926(4), b = 12.7565(4), c = 17.6895(6) Å, α = 92.757(2), β = 109.806(2), γ = 116.116(1)°. All these compounds contain molecular [(Zr6B)Cl12(CH3CN)6]+ cluster cations, [MIIICl4]– anions (MIII = Al, Ga or In) and in the case of 2 and 3 cocrystallized CH3CN molecules.
Bismuth Modified Disposable Pencil‐Lead Electrode for Simultaneous Determination of 2‐Nitrophenol and 4‐Nitrophenol by Net Analyte Signal Standard Addition Method
Authors: Asadpour‐Zeynali Karim , Najafi‐Marandi Parvaneh 
Published: July 2011

AbstractA pencil‐lead electrode modified with a thin film of bismuth, that is “environmental friendlier” than mercury, was used for electrocatalytic reduction of 2‐nitrophenol (2‐NP) and 4‐nitrophenol (4‐NP) by differential pulse voltammetry and net analyte signal standard addition method (NASSAM). The modified electrode has electrocatalytic behavior toward reduction of 2‐NP and 4‐NP. Because of similar structures of analytes, at the modified electrode they have high overlapped signals that determination of them in the presence of each other is impossible with univariate methods. NASSAM is a very recently introduced method that is a new modification of the standard addition method, which was used for the simultaneous determination of 2‐NP and 4‐NP.
Impedimetric Immunosensor for Detection of Plum Pox Virus in Plant Extracts
Authors: Jarocka Urszula , Wąsowicz Michał , Radecka Hanna , Malinowski Tadeusz , Michalczuk Lech , Radecki Jerzy 
Published: July 2011

AbstractThis paper concerns the development of an immunosensor for detection of Plum pox virus in plant extracts. The sensor was based on gold electrodes modified with: 1,6‐hexanedithiol, gold nanoparticles, anti‐PPV IgG polyclonal antibody and BSA. It was used for determination of the virus in extracts from plum (Prunus domestica) and tobacco (Nicotiana benthamiana) leaves. The proposed electrochemical impedance spectroscopy (EIS) immunosensor displayed a very good detection limit of 10 pg/mL and a wide dynamic range from 10 pg PPV/ mL to 200 pg/mL. The presence of extracts from plant materials has no influence on the immunosensor’s response. The immunosensor was capable of discriminating between samples from healthy plants and samples containing 0.01 % of extract from infected plant material. The conditions for immunosensor regeneration are also presented.
Applications of multifunctional magnetic nanoparticles for the enrichment of proteins for PAGE separation
Authors: Sun Binjie , Huang Lingyun , Na Na , He Dacheng , Ouyang Jin 
Published: July 2011

AbstractThis paper describes the applications of multifunctional magnetic nanoparticles (MNPs) for the enrichment of low‐abundance proteins for polyacrylamide gel electrophoresis (PAGE) separation. The hemoglobin‐functionalized MNPs, named Hb–MNPs, were obtained based on electrostatic interactions and covalent binding between the hemoglobin (Hb) and the MNPs. It was demonstrated that the proteins in human serum were selectively conjugated to Hb‐MNPs, which can be used for the selective enrichment of low‐abundance proteins. Three and seven kinds of proteins were identified by MS after 1‐D and 2‐D PAGE, respectively. Comparing with native PAGE without the treatment of MNPs, some proteins were observed, such as human serum amyloid P component (SAP), vitamin D‐binding protein, and serine peptidase inhibitor. Because the high concentration of SAP can be considered as a signal for the neurodegeneration of Alzheimer's disease, the present Hb‐MNPs‐based method was applied to investigate the serum level of SAP for the diagnosis of Alzheimer's disease, and the results are satisfying.
Trapping and imaging of micron‐sized embryos using dielectrophoresis
Authors: Khoshmanesh Khashayar , Kiss Nimrod , Nahavandi Saeid , Evans Clive W. , Cooper Jonathan M. , Williams David E. , Wlodkowic Donald 
Published: July 2011

AbstractDevelopment of dielectrophoretic (DEP) arrays for real‐time imaging of embryonic organisms is described. Microelectrode arrays were used for trapping both embryonated eggs and larval stages of Antarctic nematode Panagrolaimus davidi. Ellipsoid single‐shell model was also applied to study the interactions between DEP fields and developing multicellular organisms. This work provides proof‐of‐concept application of chip‐based technologies for the analysis of individual embryos trapped under DEP force.
Determination of gadolinium‐based magnetic resonance imaging contrast agents by micellar electrokinetic capillary chromatography
Authors: Andrási Melinda , Gáspár Attila , Kovács Otilia , Baranyai Zsolt , Klekner Álmos , Brücher Ernő 
Published: July 2011

AbstractMEKC with DAD was applied to detect six Gd‐based contrasting agents (CAs) (Gd‐DTPA‐BMA (Omniscan), Gd‐HPDO3A (ProHance), Gd‐DOTA (Dotarem), Gd‐AAZTA, Gd‐BOPTA (Multihance) and Gd‐DTPA (Magnevist)) commonly used in MRI diagnostics. The achieved LODs ranged between 0.40 and 20 μM and the optimized method gave excellent precision, especially when two internal standards were applied (less than 0.34 RSD% for migration time). The MEKC technique made it possible to determine the CAs in urine and serum samples of patients having a therapeutic dose. Due to the SDS content of the running buffer, the serum samples can be directly injected to analyze Gd‐based CAs without interference of high protein content.
High‐throughput functional marker assay for detection of Xa/xa and fgr genes in rice (Oryza sativa L.)
Authors: Salgotra Romesh K. , Millwood Reginald J. , Agarwal Sujata , Stewart C. Neal 
Published: July 2011

AbstractWe apply CE for high‐throughput analysis of functional markers for marker‐assisted selection in rice. The accuracy, throughput and reproducibility of CE analysis for sequence‐tagged site (STS) and simple sequence repeat (SSR) markers for bacterial blight resistance and aroma genes are demonstrated by using a CE system. Multiplex PCR products displayed well‐differentiated allelic variants using different STS and SSR markers for identification of xa13, Xa21 and fgr genes using the CE system compared to 1.2% agarose gel images. Moreover, consumption of PCR product is much less in the CE system compared to traditional agarose gel systems. Sample consumption is less than 0.1 μL per analysis, thereby conserving samples for further downstream analysis. Out of 29 genotypes in BC1F3 generation, 16 plants were found homozygous for all the three genes, viz., xa13, Xa21 and fgr. These homozygous lines can be used as potential donors in rice breeding programmes.
Binge Eating and Temperament in Morbidly Obese Prebariatric Surgery Patients
Authors: Müller Astrid , Claes Laurence , Mitchell James E. , Fischer Julia , Horbach Thomas , de Zwaan Martina 
Published: July 2011

AbstractThe objective of this study was to investigate the relationship between binge eating and temperament variables, controlling for depression and adult attention deficit/hyperactivity disorder (ADHD), in 90 extremely obese individuals. The participants completed questionnaires assessing eating pathology, reactive temperament, effortful control, depression and ADHD and were grouped based on the presence of regular binge eating. Patients reporting regular binge eating did not differ from patients not reporting regular binge eating with respect to BMI, age, gender, the occurrence of adult ADHD and reactive temperament. However, individuals with binge eating exhibited more pathological scores with regard to eating pathology, depression and effortful control. A logistic regression analysis revealed that only eating concerns and reduced effortful control remained significantly associated with regular binge eating. Binge eating in morbidly obese individuals appears to be associated with a lack of effortful control. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.