bluuebunny/crossref_metadata_2025 huggingface dataset:
Basis set convergence of electric properties in HF and DFT calculations of nucleic acid bases
Authors: Campos C. T. , Jorge F. E.
Published: August 2008

Recently, a hierarchical sequence of augmented basis sets of double, triple, and quadruple zeta valence quality plus polarization functions (AXZP, X = D, T, and Q) for the atoms from H to Ar were presented by Jorge et al. We report a systematic study of basis sets required to obtain accurate values of several electric properties for benzene, pyridine, the five common nucleic acid bases (uracil, cytosine, thymine, guanine, and adenine), and three related bases (fluorouracil, 5‐methylcytosine, and hypoxanthine) at their full optimized geometries. Two methods were examined: Hartree‐Fock (HF) and density functional theory (DFT). Including electron correlation decreases the magnitude of the dipole moment and increases the mean polarizability and also the polarizability anisotropy for every molecule. Calculated B3LYP/ADZP dipole moments and dipole polarizabilities show good agreement with both experimental and ab initio results based on second‐order Møller‐Plesset perturbation theory calculations. We have also showed that a basis set of double zeta quality is enough to obtain reliable and accurate electric property results for this kind of compounds. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
A new expansion of the leaky aquifer function
Authors: Pinchon Didier , Hoggan Philip E. , Harris Frank E.
Published: August 2008

A new expansion is presented for the incomplete Bessel function also known as the leaky aquifer function, and the computational efficiency of that expansion for prespecified relative accuracy is compared with that of other evaluation methods. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Synchronization patterns in spaghetti‐like nanoclusters
Authors: Purqon Acep , Nagao Hidemi , Nishikawa Kiyoshi
Published: August 2008

Spaghetti‐like nanoclusters concern disordered shapes and irregular shape fluctuations in few correlated biological lipids. We evaluate the shape fluctuations by introducing Symmetry‐S as a physical parameter for measuring symmetry degrees and detecting shape transitions. From numerical simulation of few correlated lipids of POPC and POPE at 300 K and 340 K by using molecular dynamics, we investigate the symmetry dynamics for each individual cluster by analyzing both spatiotemporal and frequency. From spatiotemporal analysis, we find several jump motions in S‐dynamics and non‐Gaussian distributions in S‐distribution. Interestingly, the jump motions likely contribute on the existence of transitions in the non‐Gaussian distributions. Additionally, even number of lipids show more symmetric than the odd number of lipids and the symmetry distributions shift at higher temperature, while, from three dimension of actual position of symmetry dynamics, they are not easy to configure high symmetry as well as showing certain patterns. From power spectra density analysis, each individual cluster shows nearly random fluctuation. Besides individual clusters, we also investigate mutual clusters. Surprisingly, although individual clusters show fluctuations randomly, mutual clusters show certain direction correlations. Moreover, they show certain patterns in delayed time analysis such as mutual fluctuations periodically occur for same number of lipids. It indicates that an existence of synchronization patterns occur in shape fluctuations of spaghetti‐like nanoclusters. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Two‐stage design for dose‐finding that accounts for both efficacy and safety
Authors: Dragalin Vladimir , Fedorov Valerii V. , Wu Yuehui
Published: August 2008

We introduce a two‐stage design for dose‐finding in the context of Phase I/II studies, where two binary correlated endpoints are available, for instance, one for efficacy and one for toxicity. The bivariate probit model is used as a working model for the dose–response relationship. Given a ‘desirable point’ for the marginal probabilities of efficacy and toxicity, the goal is to find the target dose that is ‘closest’ to the desirable point. The criterion of optimality (objective function) is the variance of the estimator for that dose. Optimal experimental design methodology is used to construct efficient dose allocation procedures that treat patients in the study at doses that are both safe and efficacious. Copyright © 2008 John Wiley & Sons, Ltd.
A comparison of regression calibration, moment reconstruction and imputation for adjusting for covariate measurement error in regression
Authors: Freedman Laurence S. , Midthune Douglas , Carroll Raymond J. , Kipnis Victor
Published: August 2008

Regression calibration (RC) is a popular method for estimating regression coefficients when one or more continuous explanatory variables, X, are measured with an error. In this method, the mismeasured covariate, W, is substituted by the expectation E(X|W), based on the assumption that the error in the measurement of X is non‐differential. Using simulations, we compare three versions of RC with two other ‘substitution’ methods, moment reconstruction (MR) and imputation (IM), neither of which rely on the non‐differential error assumption. We investigate studies that have an internal calibration sub‐study. For RC, we consider (i) the usual version of RC, (ii) RC applied only to the ‘marker’ information in the calibration study, and (iii) an ‘efficient’ version (ERC) in which the estimators (i) and (ii) are combined. Our results show that ERC is preferable when there is non‐differential measurement error. Under this condition, there are cases where ERC is less efficient than MR or IM, but they rarely occur in epidemiology. We show that the efficiency gain of usual RC and ERC over the other methods can sometimes be dramatic. The usual version of RC carries similar efficiency gains to ERC over MR and IM, but becomes unstable as measurement error becomes large, leading to bias and poor precision. When differential measurement error does pertain, then MR and IM have considerably less bias than RC, but can have much larger variance. We demonstrate our findings with an analysis of dietary fat intake and mortality in a large cohort study. Copyright © 2008 John Wiley & Sons, Ltd.
What is the difference? Evidence on the distribution of wealth, health, life expectancy, and health insurance coverage
Authors: Kennickell Arthur B.
Published: August 2008

There is a literature of long standing that considers the relationship between income and differentials in mortality and morbidity, but information on differentials over the distribution of accumulated wealth have been far more scarce and subject to measurement problems. This paper provides evidence from the Survey of Consumer Finances, which is designed as a survey of wealth, on the distribution of wealth and income and how those distributions have shifted in recent years. Particular attention is paid to the distribution of wealth across minority groups and across age groups. The paper also examines the relationship between wealth and health status, life expectancy, and health insurance coverage. Copyright © 2008 John Wiley & Sons, Ltd.
A random change point model for assessing variability in repeated measures of cognitive function
Authors: Dominicus Annica , Ripatti Samuli , Pedersen Nancy L. , Palmgren Juni
Published: August 2008

Some cognitive functions undergo transitions in old age, which motivates the use of a change point model for the individual trajectory. The age when the change occurs varies between individuals and is treated as random. We illustrate the properties of a random change point model and use it for data from a Swedish study of change in cognitive function in old age. Variance estimates are obtained from Markov chain Monte Carlo simulation using Gibbs sampling. The random change point model is compared with models within the family of linear random effects models. The focus is on the ability to capture variability in measures of cognitive function. The models make different assumptions about the variance over the age span, and we demonstrate that the random change point model has the most reasonable structure. Copyright © 2008 John Wiley & Sons, Ltd.
Direct estimation of the area under the receiver operating characteristic curve in the presence of verification bias
Authors: He Hua , Lyness Jeffrey M. , McDermott Michael P.
Published: August 2008

The area under a receiver operating characteristic (ROC) curve (AUC) is a commonly used index for summarizing the ability of a continuous diagnostic test to discriminate between healthy and diseased subjects. If all subjects have their true disease status verified, one can directly estimate the AUC nonparametrically using the Wilcoxon statistic. In some studies, verification of the true disease status is performed only for a subset of subjects, possibly depending on the result of the diagnostic test and other characteristics of the subjects. Because estimators of the AUC based only on verified subjects are typically biased, it is common to estimate the AUC from a bias‐corrected ROC curve. The variance of the estimator, however, does not have a closed‐form expression and thus resampling techniques are used to obtain an estimate. In this paper, we develop a new method for directly estimating the AUC in the setting of verification bias based on U‐statistics and inverse probability weighting (IPW). Closed‐form expressions for the estimator and its variance are derived. We also show that the new estimator is equivalent to the empirical AUC derived from the bias‐corrected ROC curve arising from the IPW approach. Copyright © 2008 John Wiley & Sons, Ltd.
Negative cognitions in emotional problems following romantic relationship break‐ups
Authors: Boelen Paul A. , Reijntjes Albert
Published: August 2008

This study examined the role of negative cognitions in emotional problems following relationship dissolution. Seventy‐nine undergraduate students who experienced a relationship break‐up completed measures of break‐up related complicated grief, depression and anxiety, together with an adjusted version of the Grief Cognitions Questionnaire (GCQ) that assesses four types of global negative beliefs, negative cognitions about self‐blame and the responses of others, and three types of negative interpretations of one's own grief reactions. Results showed that all cognitive variables tapped by the GCQ were significantly associated with complicated grief, and—except for global beliefs about life—with depression and anxiety. Most of these associations remained significant when controlling for the influence of initiator status, variables linked with the ended relationship (e.g. duration) and personality factors (e.g. attachment anxiety, neuroticism). Catastrophic misinterpretations about one's own reactions, global negative beliefs about the self and cognitions reflecting self‐blame were the strongest cognitive correlates of break‐up related emotional problems. Overall, the findings are in keeping with cognitive models of trauma and loss, and suggest that changing negative cognitions could be a useful intervention for those who fail to recover from a relationship break‐up. Copyright © 2008 John Wiley & Sons, Ltd.
Organizational responses to environmental demands: opening the black box
Authors: Delmas Magali A. , Toffel Michael W.
Published: August 2008

This article combines new and old institutionalism to explain differences in organizational strategies. We propose that differences in the influence of corporate departments lead their facilities to prioritize different external pressures and thus adopt different management practices. Specifically, we argue that external constituents—including customers, regulators, legislators, local communities, and environmental activist organizations—who interact with influential corporate departments are more likely to affect facility managers' decisions. As a result, managers of facilities that are subjected to comparable institutional pressures adopt distinct sets of management practices that appease different external constituents. We test our framework in the context of the adoption of environmental management practices using an original survey and archival data obtained for nearly 500 facilities. We find support for these hypotheses. Copyright © 2008 John Wiley & Sons, Ltd.
Mesoporous Silica Nanoparticles as a Delivery System of Gadolinium for Effective Human Stem Cell Tracking
Authors: Hsiao Jong‐Kai , Tsai Chih‐Pin , Chung Tsai‐Hua , Hung Yann , Yao Ming , Liu Hon‐Man , Mou Chung‐Yuan , Yang Chung‐Shi , Chen Yao‐Chang , Huang Dong‐Ming
Published: August 2008

The progress of using gadolinium (Gd)‐based nanoparticles in cellular tracking lags behind that of superparamagnetic iron oxide (SPIO) nanoparticles in magnetic resonance imaging (MRI). Here, dual functional Gd‐fluorescein isothiocyanate mesoporous silica nanoparticles (Gd‐Dye@MSN) that possess green fluorescence and paramagnetism are developed in order to evaluate their potential as effective T1‐enhancing trackers for human mesenchymal stem cells (hMSCs). hMSCs are labeled efficiently with Gd‐Dye@MSN via endocytosis. Labeled hMSCs are unaffected in their viability, proliferation, and differentiation capacities into adipocytes, osteocytes, and chondrocytes, which can still be readily MRI detected. Imaging, with a clinical 1.5‐T MRI system and a low incubation dosage of Gd, low detection cell numbers, and short incubation times is demonstrated on both loaded cells and hMSC‐injected mouse brains. This study shows that the advantages of biocompatibility, durability, high internalizing efficiency, and pore architecture make MSNs an ideal vector of T1‐agent for stem‐cell tracking with MRI.
EPR Spectroscopy Reveals Nanoinhomogeneities in the Structure and Reactivity of Thermoresponsive Hydrogels
Authors: Junk Matthias J. N. , Jonas Ulrich , Hinderberger Dariush
Published: August 2008

The dynamic and chemical behavior of solute molecules inside new thermoresponsive hydrogels (photocrosslinked poly(N‐isopropylacrylamide) (pNiPAAm) copolymers) is studied by continuous‐wave electron paramagnetic resonance spectroscopy. Via addition of paramagnetic tracer molecules (so‐called spin probes) a picture is obtained of the thermally induced collapse on the molecular scale, which proceeds over a substantially broader temperature range than indicated by the sharp macroscopic volume transition. The sampling of hydrophilic and hydrophobic environments suggests a discontinuous collapse mechanism with a coexistence of collapsed and expanded network regions. These structural inhomogeneities on the nanoscale also lead to an inhomogeneity in chemical reactivity. The hydrophilic regions form nanoreactors, which strongly accelerate the reaction while the hydrophobic regions act as nanoshelters, in which enclosed spin probes are protected from the decay. The results show that the system consisting of a statistical binary or tertiary copolymer displays remarkably complex behavior that mimics spatial and chemical inhomogeneities observed in functional biopolymers such as enzymes.
An Investigation into the Interactions Between Self‐Assembled Adenine Molecules and a Au(111) Surface
Authors: Kelly Ross E. A. , Xu Wei , Lukas Maya , Otero Roberto , Mura Manuela , Lee Young‐Joo , Lægsgaard Erik , Stensgaard Ivan , Kantorovich Lev N. , Besenbacher Flemming
Published: August 2008

Two molecular phases of the DNA base adenine (A) on a Au(111) surface are observed by using STM under ultrahigh‐vacuum conditions. One of these phases is reported for the first time. A systematic approach that considers all possible gas‐phase two‐dimensional arrangements of A molecules connected by double hydrogen bonds with each other and subsequent ab initio DFT calculations are used to characterize and identify the two phases. The influence of the gold surface on the structure of A assemblies is also discussed. DFT is found to predict a smooth corrugation potential of the gold surface that will enable A molecules to move freely across the surface at room temperature. This conclusion remains unchanged if van der Waals interaction between A and gold is also approximately taken into account. DFT calculations of the A pairs on the Au(111) surface show its negligible effect on the hydrogen bonding between the molecules. These results justify the gas‐phase analysis of possible assemblies on flat metal surfaces. Nevertheless, the fact that it is not the most stable gas‐phase monolayer that is actually observed on the gold surface indicates that the surface still plays a subtle role, which needs to be properly addressed.
An AFM/Rotaxane Molecular Reading Head for Sequence‐Dependent DNA Structures
Authors: Ashcroft Brian A. , Spadola Quinn , Qamar Shahid , Zhang Peiming , Kada Gerald , Bension Rouvain , Lindsay Stuart
Published: August 2008

DNA secondary structure may prove to be a significant obstacle both for enzymes that process DNA through an orifice and for the passage of DNA through nanopores proposed for some novel sequencing schemes. A nanomechanical molecular “tape reader” is assembled by threading a nanopore over DNA and pulling it using an atomic force microscope. Its formation is confirmed by studying the force required to open hairpins under that geometry. Unfolding induced by this 0.7‐nm‐diameter aperture requires 40 times more force than that reported for pulling on the ends of the DNA. Kinetic analysis shows that much less strain is required to destabilize the double helix in this geometry. Consequently, much more force is required to provide the free energy needed for opening.
Coalition analysis in the graph model for conflict resolution
Authors: Inohara Takehiro , Hipel Keith W.
Published: August 2008

Stability definitions for use in coalition analysis are developed within the framework of the Graph Model for Conflict Resolution. Specifically, based on the concept of joint movement by members of a coalition, the noncooperative stability definitions of Nash, general metarational, symmetric metarational, and sequential stability are extended for employment in coalition analysis. To demonstrate how the coalition stability definitions can be conveniently applied to an actual conflict, they are used to investigate a dispute arising over the pollution of an aquifer by a chemical plant located in Elmira, Ontario, Canada, and thereby obtain valuable strategic insight regarding cooperative behavior. © 2008 Wiley Periodicals, Inc. Syst Eng
An obsolescence management framework for system baseline evolution—Perspectives through the system life cycle
Authors: Herald Tom , Verma Dinesh , Lubert Caroline , Cloutier Robert
Published: August 2008

In military, civil, and commercial systems there exists a need to affordably manage the operational effectiveness of the system of interest through the acquisition and operational stages of its life cycle. Once a system design is baselined and instantiated, then the challenge during development, production, and utilization life cycle stages is to maintain the currency of the physical system baseline to facilitate affordable system support. In essence, the system must adapt to potentially frequent asynchronous obsolescence of its constituent elements, requirements growth (driven by the operational environmental and external constraints such as funding, schedule or risk), and external environment changes. This paper specifically addresses the impact that system element obsolescence has on a system baseline during the various system life cycle phases and provides a framework for affordable system evolution. Literature search and consolidation has articulated six integral components that comprise a comprehensive evolution framework through bottoms‐up obsolescence management of constituent system elements. Each of the obsolescence management components is tangibly addressed in terms of each system life cycle phase and the available tools and methods. Additionally, each of the obsolescence management framework components is analyzed for life cycle phase applicability and then extended further with the criticality and type of analysis to be done for that life cycle phase. In this way, a project can determine which studies to perform, while in a specific life cycle phase, that maximizes the insight of impending obsolescence for a particular system. © 2008 Wiley Periodicals, Inc. Syst Eng
Should you manage ethics or corruption?
Authors: Unruh Gregory
Published: August 2008

Corruption is truly a global scourge. Ethical scandals are recurring theater on the business stage, coming most often in the wake of financial booms that feed individual greed and lead managers to make decisions that favor personal gain over organizational good. The recurring cycle of scandalreform‐scandal, however, demonstrates the challenges of ethics management. Some companies are discovering a better way to confront the challenge and managing not just ethics, but corruption as well. The advantage of a corruption perspective lies in its focus on systems instead of a personal philosophy. Taking a corruption management perspective doesn't ignore the individual but sees the individual in a larger systemic context. Taking a corruption management approach requires fusing the insights of managerial ethics with the tactics used to fight systemic corruption. When successful it creates something simple and elegant: integrity. © 2008 Wiley Periodicals, Inc.
An interview with Eric M. Pillmore: Hitting the CSR bull's‐eye in a shifting corporate environment
Authors: Staczek John J.
Published: August 2008

Eric M. Pillmore served as the senior vice president of corporate governance for Tyco International Ltd. from 2002 to 2007. Working with the board of directors and the Tyco leadership team, Pillmore helped transform Tyco from an image of poor governance to a role as a leader in corporate governance. These efforts resulted in Tyco being named by GMI as the most improved U.S. company in the governance area from 2002 to 2005.

Prior to Tyco, he served as senior vice president and CFO for Multilink Technology. Pillmore worked for General Instrument Corp (GI) from 1996 to 2000 and served as senior vice president and CFO from December 1997 to January 2000, leading up to the sale of GI to Motorola. In addition, he served for 17 years in a variety of senior finance roles for General Electric from 1979 to 1996, including roles as CFO for GE Plastics Americas and GE Medical Systems Asia. He also served as a US Navy officer from 1975 to 1979, aboard the USS Robison in the western Pacific, and as an auditor with the Naval Audit Service in Washington, D.C.

Pillmore has a master's in business administration from the Villanova School of Business and a bachelor's degree in business administration from the Anderson School of Business at the University of New Mexico. He currently serves on the boards of the CEO Forum, Focus on the Family, the Ken Blanchard School of Business, the Anderson Schools of Management, and the Pillmore Family Foundation. © 2008 Wiley Periodicals, Inc.
Ethical turnarounds and transformational leadership: A global imperative for corporate social responsibility
Authors: Puffer Sheila M. , McCarthy Daniel J.
Published: August 2008

A company's social responsibility grounded in appropriate ethical values. Accountability for this foundation lies with the corporate leadership, which is responsible for establishing organizational values and culture. When a breach occurs in this leadership process, or when a transition‐economy organization is entering the global arena, an ethical turnaround is generally needed. We created this term to describe the leadership process needed to regain, or initially establish, corporate credibility and legitimacy in the eyes of stakeholders. These leadership requirements go beyond those needed in a strategic turnaround since they must help resuscitate an organization's cusses transformational leadership during ethical turnarounds in developed economies (focusing on Tyco) and in transition economies (focusing on Troika Dialog in Russia). We conclude with implications for business leaders in both economic settings. © 2008 Wiley Periodicals, Inc.
Internationalization and performance of Indian pharmaceutical firms
Authors: Kumar Vikas , Singh Nitish
Published: August 2008

This study explores the nature of the degree of internationalization and performance (DOI‐P) relationship in the context of the Indian pharmaceutical industry. The study relies on the stages model of internationalization to posit for specific relationships between DOI and performance in the distinct stages of international expansion. The findings are different from those of similar studies on emerging markets that have used a broader set of industries in their sample. Researchers should adopt caution when making any generalization of the DOI‐P relationship across contexts. Industry context in certain instances can be more powerful than country context in shaping the DOI‐P for particular firms. © 2008 Wiley Periodicals, Inc.
Role of Activated Protein C on Wound Healing Process in Left Colonic Anastomoses in the Presence of Intra‐abdominal Sepsis Induced by Cecal Ligation and Puncture: An Experimental Study in the Rat
Authors: Teke Zafer , Sacar Suzan , Yenisey Cigdem , Atalay A. Ozgur , Kavak Tulay , Erdem Ergun
Published: August 2008

Background

Activated protein C (APC) is a serine protease with anticoagulant and anti‐inflammatory activities. The delaying effects of intra‐abdominal sepsis on wound healing process in colonic anastomoses have been previously demonstrated. This study was designed to investigate the role of APC on wound healing process in left colonic anastomoses in the presence of intra‐abdominal sepsis.

Methods

The left colonic anastomosis was performed in 48 rats that were divided into four groups: (1) sham‐operated group, laparatomy plus cecal mobilization (n = 12); (2) sham + APC group, identical to group I except for APC treatment (n = 12); (3) CLP group, cecal ligation and puncture (n = 12); 4) CLP + APC‐treated group, 100 μg/kg, 15 min before the construction of colonic anastomosis (n = 12). Anastomotic bursting pressures were measured in vivo on day 7. Tissue samples were obtained for analyses of hydroxyproline (HP) contents, myeloperoxidase (MPO) acivity, malondialdehyde (MDA), and nitrate/nitrite (NO3−/NO2−) levels. The plasma levels of tumor necrosis factor α (TNF‐α), interleukin (IL)‐6, and D‐dimer also were measured.

Results

Intra‐abdominal sepsis led to significant decreases in colonic anastomotic bursting pressures and tissue HP contents, along with increases in MPO activity, MDA and NO3−/NO2− levels, and also plasma levels of TNF‐α, IL‐6, and D‐dimer (P < 0.05). However, APC treatment led to significant increases in anastomotic bursting pressures and tissue HP ontents, along with decreases in MPO activity, MDA and NO3−/NO2− levels, and also plasma levels of TNF‐α, IL‐6, and D‐dimer (P < 0.05).

Conclusions

This study clearly showed that APC treatment prevented the delaying effects of intra‐abdominal sepsis on colonic anastomotic wound healing process. Further clinical studies are required to determine whether APC has a useful role in the enhancement of anastomotic healing during particular surgeries in which sepsis‐induced injury occurs.
Use of “House” Advancement Flap in Anorectal Diseases
Authors: Alver Olcay , Ersoy Yeliz Emine , Aydemir Ismail , Erguney Sabri , Teksoz Serkan , Apaydin Berat , Ertem Metin
Published: August 2008

Background

A retrospective review of 28 patients who had “house flap” anoplasty was carried out to evaluate the therapeutic effectiveness of the procedure.

Methods

House flap anoplasty was performed at Istanbul University Cerrahpasa Medical School, General Surgery Department, in 28 patients over 4 years. Indications were chronic anal fissure, anal stenosis, high transsphincteric fistula, low rectovaginal fistula, anal neoplasia, and obstetric third‐degree perineal tear and incontinence. After rectangular excision of the anal or perianal lesion, the “walls” and “roof” of the house flap were incised to the depth of ischiorectal fat. The “base” of this house‐shaped flap was then fixed to the top of the excised area.

Results

Median postoperative hospital stay was 4.86 (range = 2–12) days. Postoperative complications included three patients with minimal wound dehiscence and one with rectovaginal fistula recurrence. At a median follow‐up of 26.4 (range = 1–46) months, excluding the patient with recurrence, all patients were satisfied with house flap anoplasty.

Conclusion

House advancement flap anoplasty is a relatively simple procedure, combining the beneficial features of rectangular flaps and V‐Y plasties. It can be used in nearly all types of anoderm deficiencies with a high rate of success and patient satisfaction.
Transient synchronization following invasion: revisiting Moran's model and a case study
Authors: Bjørnstad Ottar N. , Liebhold Andrew M. , Johnson Derek M.
Published: August 2008

Synchrony in forest insect outbreaks is important because the resulting regionalized outbreak dilutes the regulating effects of natural enemies, reduces the landscape's ability to buffer the disturbance, exacerbates the economic burden on individual stakeholders, and overwhelms the logistical abilities of managers to suppress populations and mitigate impacts. Understanding the process of synchronization of dynamics is therefore a crucial aspect of understanding outbreak dynamics. We studied the second‐order log‐linear (autoregressive) model to ask what patterns of synchronization across invasion fronts may be expected from Moran's model. Generally, we show that the time to synchronization in the log‐linear model is a complex function of a number of parameters of which the overall strength of regulation, the strength of delayed statistical density dependence, and the relaxation time seem to be of particular importance. Interestingly, while environmental correlation is the crucial determinant of the magnitude of asymptotic synchrony, it does not appear to influence the transient process of synchronization. However, synchronization proceeds much more quickly among weakly periodic populations than among populations that are strongly periodic. As a case study, we investigate synchronization following colonization by gypsy moth (Lymantria dispar) populations located along the species's expanding invasion front in northeastern USA. Data consisted of more than 100 years of county quarantine records and 30 years of detailed defoliation maps. We found that the dynamics of new populations tended to be initially out of synch with the broadly synchronized outbreaks within the established range. However, the outbreak dynamics of these new populations lock on to the regional patterns very quickly—within 10–15 years of invasion. Focusing on parameters that produce periodicity comparable to that seen in real gypsy moth populations, we discuss how the observed synchronization compares to that predicted by the log‐linear model. While our results are equivocal, the synchronization appears to be surprisingly rapid, so more mechanistic models may be needed to explain the synchronization observed in this case study.
Mutual Help Groups for Mental Health Problems: A Review of Effectiveness Studies
Authors: Pistrang Nancy , Barker Chris , Humphreys Keith
Published: August 2008

This paper reviews empirical studies on whether participating in mutual help groups for people with mental health problems leads to improved psychological and social functioning. To be included, studies had to satisfy four sets of criteria, covering: (1) characteristics of the group, (2) target problems, (3) outcome measures, and (4) research design. The 12 studies meeting these criteria provide limited but promising evidence that mutual help groups benefit people with three types of problems: chronic mental illness, depression/anxiety, and bereavement. Seven studies reported positive changes for those attending support groups. The strongest findings come from two randomized trials showing that the outcomes of mutual help groups were equivalent to those of substantially more costly professional interventions. Five of the 12 studies found no differences in mental health outcomes between mutual help group members and non‐members; no studies showed evidence of negative effects. There was no indication that mutual help groups were differentially effective for certain types of problems. The studies varied in terms of design quality and reporting of results. More high‐quality outcome research is needed to evaluate the effectiveness of mutual help groups across the spectrum of mental health problems.
Human carbamoyl‐phosphate synthetase: Insight into N‐acetylglutamate interaction and the functional effects of a common single nucleotide polymorphism
Authors: Ahuja V. , Powers‐Lee S. G.
Published: August 2008

Human carbamoyl‐phosphate synthetase (hCPS) has evolved three features that allow it to remove excess, potentially neurotoxic ammonia via the urea cycle: inability to use glutamine as an alternative nitrogen donor; a Km for ammonia 100‐fold lower than for CPSs that also use glutamine; and required allosteric activation by N‐acetylglutamate (AGA), a sensor of excess amino acids. To determine the structural features of hCPS that allow its unique functioning, we have developed the first recombinant expression system for hCPS, utilizing Schizosaccharomyces pombe. Of several common single‐nucleotide polymorphisms identified in the gene encoding hCPS, only the one resulting in substitution of threonine at position 1406 with asparagine has been linked to phenotypic effects. We have expressed and characterized both variants of hCPS. The asparagine polymorph, hCPS_N, consistently displayed inferior catalytic properties, but the Km and kcat values for overall and partial reactions varied only by a factor of 1.7 or less. We have designed and characterized an hCPS construction from which the N‐terminal domain A is deleted. hCPS_ΔA was competent to bind AGA, demonstrating that domain A does not contain the AGA binding site. Thus, the site at the C/D boundary previously identified by AGA analogue labelling appears to be the functionally significant initial binding site for AGA. However, hCPS_ΔA was not able to fully assume the catalytically competent conformation, with specific activity of CP formation decreased 700‐fold.
Fractionation and Some Chemical Studies on Ailanthus excelsa Roxb. Seed Protein
Authors: Kundu Pijush , Laskar Subrata
Published: August 2008

The unavailability of protein foods, particularly in the context of population growth, has been an important factor in the protein malnutrition encountered in developing countries. The fractionation, gel filtration and polyacrylamide gel electrophoresis (PAGE) of Ailanthus excelsa seed (a nontraditional source containing 15.81% protein) proteins were carried out in the present study, and their solubility profiles, surface topographies and amino acid compositions were evaluated. The globulin fraction dominated the seed protein composition, accounting for 51.31% (w/w) of the total soluble proteins in the seeds. Protein isolate and protein fractions of A. excelsa seeds showed similar topographical structures to those of other plant seed proteins. Analysis of the isolated proteins identified 17 amino acids, of which nine were essential. Gel filtration on Sephadex G‐200 revealed the presence of seven components. PAGE detected different polypeptide bands in the range of 28.8−154.9 kDa in the protein isolate as well as in protein fractions for A. excelsa. The amino acid compositions, the solubility patterns and the high abundances of low molecular weight proteins indicate that the isolated seed protein of A. excelsa may be a potential food protein.
Mid‐Oleic/Ultra Low Linolenic Acid Soybean Oil: A Healthful New Alternative to Hydrogenated Oil for Frying
Authors: Warner K. , Fehr Walter
Published: August 2008

To determine the frying stability of mid‐oleic/ultra low linolenic acid soybean oil (MO/ULLSBO) and the storage stability of food fried in it, tortilla chips were fried in MO/ULLSBO, soybean oil (SBO), hydrogenated SBO (HSBO) and ultra low linolenic SBO (ULLSBO). Intermittent batch frying tests were conducted up to 55 h of frying, and then tortilla chips were aged up to 4 months at 25 °C. Frying oils were analyzed for total polar compounds to determine the frying stability of the oil. Tortilla chips were analyzed for hexanal as an indicator of oxidative deterioration and by sensory analysis using a trained, experienced analytical panel. Results showed no significant differences between the total polar compound levels for MO/ULLSBO and HSBO after 55 h of frying, indicating a similar fry life. However, total polar compound levels for ULLSBO and SBO were significantly higher than for either MO/ULLSBO or HSBO, indicating a lower oil fry life. Hexanal levels in aged tortilla chips fried in SBO were significantly higher than in chips fried in any of the other oils. Tortilla chips fried in MO/ULLSBO and HSBO had significantly lower hexanal levels than in chips fried in ULLSBO. A sensory analysis of rancid flavor intensity showed similar trends to those for hexanal formation. The chips fried in SBO had the highest rancid flavor intensity, with significantly lower hexanal levels in chips fried in HSBO and MO/ULLSBO. Based on these results, MO/ULLSBO not only had a good fry life but also produced oxidatively stable fried food, and therefore would be a healthful alternative to HSBO.
Clinical trials update from Heart Rhythm 2008 and Heart Failure 2008: ATHENA, URGENT, INH study, HEART and CK‐1827452
Authors: Coletta Alison P. , Cleland John G.F. , Cullington Damien , Clark Andrew L.
Published: August 2008

This article provides information and a commentary on trials relevant to the pathophysiology, prevention and treatment of heart failure, presented at the Heart Rhythm Society meeting in San Francisco, USA and the Heart Failure Association meeting of the European Society of Cardiology which was held in Milan, Italy in June 2008. Unpublished reports should be considered as preliminary data, as analyses may change in the final publication.

The ATHENA study showed that dronedarone reduced the incidence of the composite outcome of cardiovascular hospitalisation or death, in patients with atrial fibrillation or flutter, 29% of whom had a history of heart failure, compared with placebo. The URGENT study demonstrated that treatment of acute heart failure with standard therapy, including intravenous diuretics and nitrates, leads to a rapid resolution of breathlessness in the sitting position but that orthopnoea often persists. The INH study showed that a disease management programme could reduce mortality compared to usual care but not hospitalisation rates. The HEART study failed to recruit its planned number of patients, although it is the largest randomised trial of revascularisation in heart failure reported to date. At a median follow‐up of 5 years no difference in mortality was observed but the study lacked power to provide a conclusive result. The selective myosin activator CK‐1827452 produced a concentration dependent increase in systolic ejection time, stroke volume and fractional shortening in patients with heart failure compared to placebo.
A single residue mutation in Hha preserving structure and binding to H–NS results in loss of H–NS mediated gene repression properties
Authors: Cordeiro Tiago N. , Garcı'a Jesús , Pons José-Ignacio , Aznar Sonia , Juárez Antonio , Pons Miquel
Published: August 2008

In this study, we report that a single mutation of cysteine 18 to isoleucine (C18I) in Escherichia coli Hha abolishes the repression of the hemolysin operon observed in the wild‐type protein. The phenotype also includes a significant decrease in the growth rate of E. coli cells at low ionic strength. Other substitutions at this position (C18A, C18S) have no observable effects in E. coli growth or hemolysin repression. All mutants are stable and well folded and bind H–NS in vitro with similar affinities suggesting that Cys 18 is not directly involved in H–NS binding but this position is essential for the activity of the H–NS/Hha heterocomplexes in the regulation of gene expression.
Only plant‐type (GLYK) glycerate kinases produce d‐glycerate 3‐phosphate
Authors: Bartsch Oliver , Hagemann Martin , Bauwe Hermann
Published: August 2008

d‐Glycerate kinases (GK) occur in three phylogenetically distinct classes. Class II GKs produce glycerate 2‐phosphate, while both class I GK and class III GK (GLYK) are thought to produce glycerate 3‐phosphate. We report on the identification of a bacterial‐type class I GK in the unicellular cyanobacterium Synechocystis sp. strain PCC 6803 and of a plant‐type GLYK in the filamentous cyanobacterium Nostoc sp. strain PCC 7120. The comparison with other prokaryotic and eukaryotic GKs of both classes shows that glycerate 3‐phosphate is produced only by the GLYKs, but, in contrast to current thinking, not by any of the examined class I enzymes.
Internal translation initiation on the foot‐and‐mouth disease virus IRES is affected by ribosomal stalk conformation
Authors: Martínez-Azorín Francisco , Remacha Miguel , Martínez-Salas Encarnación , Ballesta Juan P.G.
Published: August 2008

A human cell line, in which expression of the ribosomal stalk proteins P1 and P2 has been suppressed by RNAi technology, has been used to test how the loss of these proteins affects IRES‐dependent translation. Foot‐and‐mouth disease virus (FMDV) IRES‐dependent translation from a bicistronic construct is about three fold higher in the P1/P2‐depleted cells than in control cells in the presence of Lb protease. By contrast, no effect on Hepatitis C virus (HCV) IRES translation was observed. These results emphasize the functional heterogeneity of the IRES and they highlight a functional connection between the ribosomal stalk and picornavirus IRES‐dependent translation.
Acceptor substrate binding revealed by crystal structure of human glucosamine‐6‐phosphate N‐acetyltransferase 1
Authors: Wang Juan , Liu Xiang , Liang Yu-He , Li Lan-Fen , Su Xiao-Dong
Published: August 2008

MINT:6700314:

GNA1 (uniprotkb:Q96EK6) and GNA1 (uniprotkb:Q96EK6) bind (MI:0407) by X-ray crystallography (MI:0114)
Antinociceptive and side-effects of hydromorphone after subcutaneous administration in cats
Authors: Robertson Sheilah A. , Wegner Kirsten , Lascelles Benedict Duncan X.
Published: August 2008

The subcutaneous (SC) route is often chosen for drug administration in cats because it is easier to perform than intravenous (IV) injection and is perceived as less painful than intramuscular (IM) injection. However, little is known of how the route of administration influences the pharmacodynamics of drugs. This study measured the changes in skin temperature and thermal threshold (TT) and recorded the side-effects after SC injection of 0.1 mg/kg of hydromorphone in six cats. Time to peak TT was 105 min. Skin temperature was elevated at 15 min and between 45 and 360 min. Five cats vomited and two exhibited marked dysphoria. Compared to previously published studies of IV and IM administration of hydromorphone, the SC route results in a slower onset of peak effect, a shorter duration of antinociception and is associated with more undesirable side-effects. As with IV and IM injections, SC administration of hydromorphone at 0.1 mg/kg is associated with a significant elevation in skin temperature. Overall, the SC route appears to have the least utility.
Production of hydrogen peroxide by a small molecular mass compound in milk from Holstein cows with high and low milk somatic cell count
Authors: Sakai Senkiti , Nonobe Eriko , Satow Takahiro , Imakawa Kazuhiko , Nagaoka Kentaro
Published: August 2008

Mastitis is the most frequent and prevalent production disease in dairy herds in developed countries. Based on a milk somatic cell count (SCC) of either >300 000 or <200 000 cells/ml in this study, we defined the quarter as either inflamed or uninflamed, respectively. The electrical conductivity (EC) of milk was used as an indicator of udder epithelial cell damage. We determined the amount of H2O2produced by utilizing a small molecular weight compound in milk, and examined the characteristics of H2O2production and EC in milk from inflamed and uninflamed quarters. In cows with milk of delivery grade (control population), H2O2production and EC were 3·6±1·3 nmol/ml and 5·4±0·4 mS/cm (mean±sd), respectively. In 37 inflamed quarter milk samples, the production of H2O2was 1·9±1·0 nmol/ml and was significantly smaller than that in the control population (P<0·01). Production of H2O2was moderately but significantly correlated with EC (r<−0·71). In 20 cows with inflamed quarters, the production of H2O2in milk from inflamed quarters was significantly smaller than that in milk from uninflamed quarters (P<0·01). In 18 out of 20 cows, milk from inflamed quarters showed the smallest H2O2production among all tested quarters in each cow. We conclude that inflammation caused a decrease in H2O2production in milk. In this study, we present parameters for evaluating the lactoperoxidase/H2O2/thiocyanate antibacterial defence system in bovine milk.
Evaluation of the efficacy of systemic danofloxacin in the treatment of induced acuteEscherichia colibovine mastitis
Authors: Poutrel Bernard , Stegemann Michael R , Roy Olivier , Pothier Francis , Tilt Nicola , Payne-Johnson Mark
Published: August 2008

The objective was to evaluate the efficacy of a single dose of danofloxacin (6 mg/kg bodyweight) given by the intravenous route for the treatment of acute bovine mastitis induced by intra-cisternal infusion of anEscherichia colistrain (26 cfu into one rear quarter of each cow). Twenty-three Prim'Holstein lactating cows were inoculated. To be challenged, the mammary glands had to be productive, free of pathogenic bacteria, and with somatic cell counts (SCC) of <200 000 cells/ml. The cows were treated on an individual basis when predetermined criteria involving both systemic and local clinical signs were satisfied. Allocation to treatment, danofloxacin or negative saline control, was performed according to a randomized treatment allocation plan. Monitoring during a 21-d period after inoculation included individual clinical examination, bacteriological examination and determination of SCC.Esch. coliwas isolated from the milk of all inoculated quarters at the first milking post-inoculation and, together with reference to the clinical scores; the challenge was considered to be successful in 20 of the 23 cows. On study day 7 bacteriological cure rates with danofloxacin and saline control were 89% (8/9) and 44% (4/9) respectively. On days 14 and 21 all milk samples that could be collected were negative forEsch. coliin both groups of animals. Beneficial statistically significant differences were found at the end of the observation period (days 19–21 post treatment) between cows treated with danofloxacin and saline for SCC (P=0·0091) and earlier in the study for milk production (P=0·0003) and udder inflammation (P=0·004). Obvious beneficial trends were recorded in the danofloxacin group for rectal temperature, milk quality, general behaviour and appetite. Danofloxacin-treated cows showed statistically significant lower local clinical scores and a more rapid return to pre-inoculation values. It was concluded that systemically administered danofloxacin is effective in terms of bacteriological results, milk production and both systemic and local signs when used in the treatment of induced acuteEsch. colimastitis. Danofloxacin hastens recovery and return to productivity compared with potential self cure.