bluuebunny/crossref_metadata_2025 huggingface dataset:
The extended finite element method in thermoelastic fracture mechanics
Authors: Duflot Marc
Published: September 2007

The extended finite element method (XFEM) is applied to the simulation of thermally stressed, cracked solids. Both thermal and mechanical fields are enriched in the XFEM way in order to represent discontinuous temperature, heat flux, displacement, and traction across the crack surface, as well as singular heat flux and stress at the crack front. Consequently, the cracked thermomechanical problem may be solved on a mesh that is independent of the crack. Either adiabatic or isothermal condition is considered on the crack surface. In the second case, the temperature field is enriched such that it is continuous across the crack but with a discontinuous derivative and the temperature is enforced to the prescribed value by a penalty method. The stress intensity factors are extracted from the XFEM solution by an interaction integral in domain form with no crack face integration. The method is illustrated on several numerical examples (including a curvilinear crack, a propagating crack, and a three‐dimensional crack) and is compared with existing solutions. Copyright © 2007 John Wiley & Sons, Ltd.
Improved mechanical properties and structure of PP/nano‐CaCO3 blends prepared by low‐frequency vibration injection molding
Authors: Xueqin Gao , Jing Xu , Zhanchun Chen , Cong Deng , Kaizhi Shen
Published: September 2007

BACKGROUD: Melt vibration technology was used to prepare injection samples of polypropylene (PP)/nano‐CaCO3 blends. It is well known that nano‐CaCO3 particles are easy to agglomerate owing to their large surface energy. Improving the distribution of nano‐CaCO3 particles in PP/nano‐CaCO3 blends is very important for enhancing the mechanical properties. In this work, low‐frequency vibration was imposed on the process of injection molding of PP/nano‐CaCO3 blends. The aim of importing a vibration field was to change the crystal structure of PP as we studied previously and improve the distribution of nano‐CaCO3 particles. Furthermore, the mechanical properties were improved.

RESULTS: Through melt vibration, the mechanical properties of PP/nano‐CaCO3 samples were improved significantly. Compared with conventional injection molding, the enhancement of the tensile strength and impact strength of the samples molded by vibration injection molding was 17.68 and 175.96%, respectively. According to scanning electron microscopy, wide‐angle X‐ray diffraction and differential scanning calorimetry measurements, it was found that a much better dispersion of nano‐CaCO3 in samples was achieved by vibration injection molding. Moreover, the crystal structure of PP in PP/CaCO3 vibration samples changed. The γ crystal form was achieved at the shear layer of vibration samples. Moreover, the degree of crystallinity of PP in vibration samples increased 6% compared with conventional samples.

CONCLUSION: Concerning the microstructure, melt vibration could effectively change the crystal structure and increase the degree of crystallinity of PP besides improving the distribution of nano‐CaCO3 particles. Concerning the macrostructure, melt vibration could enhance the mechanical properties. The improvement of mechanical properties of PP/nano‐CaCO3 blends prepared by low‐frequency vibration injection molding should be attributed to the even distribution of nano‐CaCO3 particles and the formation of γ‐PP and the increase of the degree of cystallinity. Copyright © 2007 Society of Chemical Industry
Intrinsic factor and vitamin B12 complex‐loaded poly[lactic‐co‐(glycolic acid)] microspheres: preparation, characterization and drug release
Authors: Demir Serap , Ogan Ayşe , Kayaman‐Apohan Nilhan
Published: September 2007

BACKGROUND: Vitamin B12 is an essential vitamin required by all mammals. Absorption of vitamin B12 is facilitated by binding of intrinsic factor–vitamin B12 complex to specific receptors in the ileum. In humans a deficiency of this vitamin or a lack of intrinsic factor leads to pernicious anaemia. The major objective of the present study was to prepare intrinsic factor–vitamin B12 complex‐loaded poly[lactic‐co‐(glycolic acid)] (PLGA)‐based microparticles and to investigate their release kinetics.

RESULTS: PLGA copolymer was synthesized by the ring‐opening polymerization method and characterized using gel permeation chromatography, Fourier transform infrared spectroscopy and 1H NMR. The glass transition temperature measurement showed a single Tg at 40 °C. The intrinsic factor–vitamin B12 complex‐loaded PLGA microspheres were prepared by a water‐in‐oil‐in‐water double emulsion solvent extraction/evaporation technique. An environmental scanning electron microscopy investigation demonstrated that the PLGA particles had a mean particle diameter of 38 µm. Interestingly, different drug release patterns (bi‐ and triphasic ones) were observed for vitamin B12‐loaded and intrinsic factor–vitamin B12 complex‐loaded microspheres. In contrast to the rapid release of vitamin B12 by itself, in vitro release tests showed that intrinsic factor and vitamin B12 in the complex were released from PLGA microspheres in a sustained manner over 15 days.

CONCLUSION: PLGA microspheres can be an effective carrier for the intrinsic factor–vitamin B12 complex. Copyright © 2007 Society of Chemical Industry
A sweat test centered protocol for the disclosure and diagnosis of cystic fibrosis in a newborn screening program
Authors: Doull I.J.M. , Hall S.J. , Bradley D.M.
Published: September 2007

Pediatric Pulmonology 2007;42(9):773–778. DOI 10.1002/ppul.20664 © 2007 Wiley‐Liss, Inc.
Prolylproline unit in model peptides and in fragments from databases
Authors: Hudáky Ilona , Perczel András
Published: September 2007

The prolylproline sequence unit is found in several naturally occurring linear and cyclic peptides with immunosuppressive and toxic activity. Furthermore, Pro–Pro units are abundant in collagen, in ligand motifs binding to SH3 or WW domains, as well as in vital enzymes such as DNA glycosylase and thrombin. In all these sequence units a special role is dedicated to conformation in order to successfully fulfill the appropriate biological function. Therefore, a detailed analysis of the basic conformational properties of Pro–Pro is expected to reveal the versatile structural role of this sequence. PCM (polarizable continuum model) calculations on the basis of ab initio and density functional theory investigations using the model peptide HCO–L‐Pro–L‐Pro–NH2 are presented. Cis–trans isomerism, backbone conformation and ring puckering are studied. A systematic comparison is made to experimental data gained on L‐prolyl–L‐proline sequence units retrieved from the Protein Data Bank as well as from the Cambridge Structural Database. PCM data are in good agreement with high‐resolution X‐ray crystallography. Population data derived from energy calculations and those gained directly from statistics predict that 87% of the Pro–Pro sequence units adopt elongated structures, while 13% form β‐turns. Both approaches prefer the same 6 out of the 36 ideally possible backbone folds. Polyproline II unit (tϵLtϵL), other elongated structures (cϵL tϵL, tϵL tαL and tϵL tγL), type VIa (tϵL cαL) and type I or III β‐turns (tαL tαL) altogether describe 96% of the prolylproline sequences. In disordered proteins or domains, Pro–Pro sequence units may sample the various conformers and contribute to the segmental motions. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Ion exclusion mechanism in aquaporin at an atomistic level
Authors: Ko Youn Jo , Huh June , Jo Won Ho
Published: September 2007

Although the mechanism of proton exclusion in aquaporin is investigated by many researchers, the detailed molecular mechanism for ion exclusion in aquaporin is still not completely understood. In the present work, a detailed mechanism for ion exclusion in aquaporin‐1 (AQP1) at an atomistic level is investigated by calculating the free energy for transport of ions in AQP1 using an atomistic molecular dynamics simulation. For this purpose, sodium and chloride ions are chosen as representatives for nonprotonic ions. The simulation shows that the free energy barrier showing its maximum is located at the NPA region for sodium ion while it is located at both the front and the rear for chloride ion and that the barrier height is 18 and 9 kcal/mol, respectively, indicating that the ions are not able to pass through aquaporin. Analysis of the pair interaction energy between the permeating ion and its environment reveals that sodium ion is excluded by the positive charge generated by two α‐helical macro‐dipoles, while chloride ion is expelled by carbonyl oxygen atoms protruding from pore‐making residues before it reaches the NPA motif. It is also found that the number of water molecules hydrating the ions is reduced as the ions enter the pore, implying that the energetic cost for detaching water molecules from a permeating ion also contributes to the free energy barriers of ion transport in AQP1. Proteins 2008. © 2007 Wiley‐Liss, Inc.
Incorporating biochemical information and backbone flexibility in RosettaDock for CAPRI rounds 6–12
Authors: Chaudhury Sidhartha , Sircar Aroop , Sivasubramanian Arvind , Berrondo Monica , Gray Jeffrey J.
Published: September 2007

In CAPRI rounds 6–12, RosettaDock successfully predicted 2 of 5 unbound–unbound targets to medium accuracy. Improvement over the previous method was achieved with computational mutagenesis to select decoys that match the energetics of experimentally determined hot spots. In the case of Target 21, Orc1/Sir1, this resulted in a successful docking prediction where RosettaDock alone or with simple site constraints failed. Experimental information also helped limit the interacting region of TolB/Pal, producing a successful prediction of Target 26. In addition, we docked multiple loop conformations for Target 20, and we developed a novel flexible docking algorithm to simultaneously optimize backbone conformation and rigid‐body orientation to generate a wide diversity of conformations for Target 24. Continued challenges included docking of homology targets that differ substantially from their template (sequence identity <50%) and accounting for large conformational changes upon binding. Despite a larger number of unbound–unbound and homology model binding targets, Rounds 6–12 reinforced that RosettaDock is a powerful algorithm for predicting bound complex structures, especially when combined with experimental data Proteins 2007. © 2007 Wiley‐Liss, Inc.
Analyzing hazards of sour water spills
Authors: Woodward J.L.
Published: September 2007

This article illustrates evaluating the consequence of a large spill of sour water by modeling the plume of hydrogen sulfide and ammonia to toxic limits. This modeling uses chemical equilibrium constants and rigorous thermodynamic formulas, coupled with dispersion modeling to show how the plume contours of H2S and of NH3 vary with initial concentrations and pH. The results show that a pH adjustment is an effective mitigation measure. © 2007 American Institute of Chemical Engineers Process Saf Prog 27, 2007
Near band‐edge 3.357 eV emission of Ga‐face (0001) GaN grown by ammonothermal method
Authors: Fujii Katsushi , Fujimoto Gakuyo , Goto Takenari , Yao Takafumi , Kagamitani Yuji , Hoshino Naruhiro , Ehrentraut Dirk , Fukuda Tsuguo
Published: September 2007

Excitonic emission was observed at 3.357 eV by photoluminescence only from the (0001) Ga‐face of GaN grown by an ammonothermal method. The emission intensity varied over the crystal surface. The temperature dependence of the emission intensity is similar to that of excitons bound to neutral donors for hexagonal (2H) GaN. The origin of the emission is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of microcrystallization on noise in boron‐doped silicon film
Authors: Li Shibin , Wu Zhiming , Li Wei , Liao Naiman , Yu Junsheng , Jiang Yadong
Published: September 2007

A series of hydrogenated silicon (Si:H) thin films of about 350 nm in thickness were fabricated on K9 glass substrate by plasma enhanced chemical vapor deposition. The transition between hydrogenated amorphous silicon (a‐Si:H) and microcrystalline hydrogenated silicon (μc‐Si:H) was characterized by atomic force microscopy and X‐ray diffraction microstructure analysis. The low‐frequency noise (1/f noise) and random telegraph switching (RTS) noise of Si:H films were measured using a designed semiconductor system. The results show that the 1/f noise of μc‐Si:H is 4 orders of magnitude lower than that of a‐Si:H and no RTS noise of Si:H films was found. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
QSAR of Novel Hydroxyphenylureas as Antioxidant Agents
Authors: Deeb Omar , Youssef Khairia M. , Hemmateenejad Bahram
Published: September 2007

A set of descriptors consisting of quantum, chemical, and topological descriptors has been used for modeling the activity of novel hydroxyphenylureas to scavenge Free Radicals (FRs) produced by Peripheral Multinuclear Neutrophil Cells (PMNs) expressed as the rate of change per unit added volume of FR (Kapp min−1). Simple as well as multiple regressions have indicated that PW2 (Path\Walk‐2‐Randic Shape Index) is the most dominating parameter to be used in modeling Kapp. Excellent results are obtained in multiparametric regressions. The results are critically discussed using a variety of statistical parameters. The models are validated using Leave‐One‐Out (LOO) and Leave‐Group‐Out (LGO) crossvalidation, external test set, and chance correlation.
Application of the statistical test of equivalent pathways (STEP) method to the triple quadrupole mass spectrometer
Authors: Dalpathado Dilusha S. , Chang Qing , Burkett Colleen M. , Bandu Mary L. , Desaire Heather
Published: September 2007

Recently, we demonstrated a new method, STEP (Statistical Test of Equivalent Pathways) analysis, which differentiates first‐generation product ions (primary product ions) from second‐generation product ions (secondary product ions) obtained in tandem mass spectrometric (MS/MS) experiments on a quadrupole ion trap mass spectrometer. The study presented here defines how to adapt the STEP method to a more routinely used mass analyzer, the triple quadrupole. New ion activation conditions were developed to adapt the STEP method to the triple quadrupole mass spectrometer using peptides and carbohydrates. The application of this method to the triple quadrupole is useful because it provides an efficient approach to differentiate primary and secondary ions on this instrument. Out of the total number of ions that were subjected to the STEP analysis, this method correctly identified 96% of ions as primary or secondary, indicating that this analysis is effective for carbohydrates and peptides undergoing collision‐induced dissociation (CID) on a triple quadrupole mass spectrometer. Copyright © 2007 John Wiley & Sons, Ltd.
Ethics of Surgical Training in Developing Countries
Authors: Ramsey Kevin M. , Weijer Charles
Published: September 2007

The practice of surgical trainees operating in developing countries is gaining interest in the medical community. Although there has been little analysis about the ethical impact of these electives, there has been some concerns raised over the possible exploitation of trainees and their patients. An ethical review of this practice shows that care needs to be taken to prevent harm. Inexperienced surgeons learning surgical skills in developing countries engender greater risk of violating basic ethical principles. Advanced surgical trainees who have already achieved surgical competence are best qualified to satisfy these ethical issues. All training programs need to develop a structured ethical review for international electives to protect their trainees and their patients from harm.
Can minimum convex polygon home ranges be used to draw biologically meaningful conclusions?
Authors: Nilsen Erlend B. , Pedersen Simen , Linnell John D. C.
Published: September 2007

Many conclusions about mammalian ranging behaviour have been drawn based on minimum convex polygon (MCP) estimates of home range size, although several studies have revealed its unpredictable nature compared to that of the kernel density estimator. We investigated to what extent the choice of home range estimator affected the biological interpretation in comparative studies. We found no discrepancy when the question asked covered a wide range of taxa, as real and very large differences in range size were likely to have masked smaller differences due to the choice of home range estimator. However, when the question asked concerned within‐species characteristics, the choice of home range estimator explained as much of the variation in range size as did the ecological variable in question. The implications for macro‐ecological and intraspecific studies are discussed.
Impacts of Bleaching and Packed Column Steam Refining on Cocoa Butter Properties
Authors: Vila Ayala José , Calliauw Gijs , Foubert Imogen , Dewettinck Koen , Dyer Bill , De Greyt Wim
Published: September 2007

Natural and alkalized cocoa butters were bleached and subsequently steam refined in a continuous packed column at temperatures ranging between 160 and 220 °C. None of the processes evaluated gave rise to any detectable formation of trans fatty acids, interesterification or polymerization. For the pressures and steam injection rates used, packed‐column steam refining required a minimum temperature of 170 °C to achieve acceptable taste. Bleaching was highly effective in preventing darkening at high steam‐refining temperatures, as well as in removing alkaloids, such as theobromine and caffeine, before steam refining. The impacts on the crystallization properties of cocoa butter were studied using DSC and P‐NMR. The more significant changes in crystallization kinetics and equilibrium values can be reliably predicted on the basis of FFA removal from the butter.
Patients Reported Health-Related Quality of Life Five Years Post Coronary Artery Bypass Graft Surgery – A Methodological Study
Authors: Lee Geraldine A.
Published: September 2007

Background: The number of individuals undergoing Coronary Artery Bypass Graft Surgery (CABGS) to treat coronary artery disease is steadily increasing.

Aim: The purpose of the study was to describe the cohort's characteristics, their angina and breathless symptoms and report health-related quality of life (HRQoL) five years after CABGS.

Methods: One hundred and twenty-eight patients participated in the follow-up study using the quality of life Short-Form 36 (SF-36) questionnaire. Angina and breathless symptoms were also recorded.

Results: One hundred and nine patients were interviewed (face-to-face) and 19 completed postal questionnaires. The SF-36 component summaries of the face-to-face patients indicated that their physical (PCS) and mental (MCS) health was relatively good (45.8 and 53.6, respectively, with 0 = worst health and 100 = best health and 50 being the mean score), compared to the postal patients' mean PCS of 30.8 ( p < .001). The postal MCS was also lower but not statistically significant (49.6, p = .081). At follow-up, the majority of patients were asymptomatic in terms of angina and breathlessness compared to their pre-operative status.

Conclusion: The findings demonstrate that patient perceived HRQoL five years after CABGS is generally good and patients remain relatively asymptomatic although data collection methods highlight differences in physical HRQoL.
Interaction of a fragment of the cannabinoid CB1 receptor C‐terminus with arrestin‐2
Authors: Bakshi Kunal , Mercier Richard W. , Pavlopoulos Spiro
Published: September 2007

Desensitization of the cannabinoid CB1 receptor is mediated by the interaction with arrestin. In this study, we report the structural changes of a synthetic diphosphorylated peptide corresponding to residues 419–439 of the CB1 C‐terminus upon binding to arrestin‐2. This segment is pivotal to the desensitization of CB1. Using high‐resolution proton NMR, we observe two helical segments in the bound peptide that are separated by the presence a glycine residue. The binding we observe is with a diphoshorylated peptide, whereas a previous study reported binding of a highly phosphorylated rhodopsin fragment to visual arrestin. The arrestin bound conformations of the peptides are compared.
Dysmenorrhea among Japanese women
Authors: Ohde S. , Tokuda Y. , Takahashi O. , Yanai H. , Hinohara S. , Fukui T.
Published: September 2007

Objective: To investigate the epidemiology of dysmenorrhea in Japanese women of menstrual age. Methods: A prospective cohort study was conducted using a health diary in a sample representative of Japanese women. Information on health care use was also collected. Results: Among 823 enrolled participants (age range, 18–51 years), dysmenorrhea (mean duration 1.75 days; range 1–5 days) was reported in 15.8% (95% CI, 13.3–18.3) during the 1‐month study period. Common associated symptoms included headache (10.77%), back pain (6.92%), and fatigue (5.38%). No participant with dysmenorrhea visited a physician, while 51.5% of the women used self‐medication, and 7.7% used complementary/alternative medicine. Conclusion: Dysmenorrhea is common in Japanese women. In our study, about half used self‐medication, while some preferred complementary/alternative medicine. Dysmenorrhea is significantly associated with younger age and employment status.
Presidentialism, Electoral Identifiability, and Budget Balances in Democratic Systems
Authors: CHEIBUB JOSÉ ANTONIO
Published: September 2007

This paper examines the impact of the form of government—presidential or parliamentary—on fiscal outcomes in democratic systems. Based on data for democracies in 98 countries between 1970 and 2002, it shows that the gross domestic product ratio of the central government budget balance is higher in presidential than in parliamentary democracies. It also shows that this impact is not due to the fact that presidential systems are not subject to the “costs of coalition” that allegedly afflict parliamentary democracies: the coalition and status of the government are of no consequence for budget balances in either presidential or parliamentary systems. Presidential systems matter for budget balances because they generate relatively high incentives for governments to keep budgets under control. They do so because in presidential systems, unlike in parliamentary systems, voters are by design able to identify and punish those responsible for economic policies. Presidents, however, vary in their capacity to affect budget policies. This paper demonstrates that presidential systems in which presidents are constitutionally able to dominate the budget process or to effectively veto legislation tend to have higher budget balances than those in which the budget process is dominated by the legislature or the president is unable to exercise existing veto powers.
Optimal Obfuscation: Democracy and Trade Policy Transparency
Authors: KONO DANIEL Y.
Published: September 2007

A growing body of research shows that democracies have more liberal trade policies than do autocracies. I argue, in contrast, that democracy has contradictory effects on different types of trade policies because electoral competition generates more information about some than about others. It generates considerable information about policies whose effects on consumer welfare are easy to explain to voters, but less information about policies whose effects are more complex. By increasing the transparency of some policies relative to others, democracy induces politicians to reduce transparent trade barriers but also to replace them with less transparent ones. I test this hypothesis by examining the impact of democracy on tariffs, “core” nontariff barriers (NTBs) such as quotas, and “quality” NTBs such as product standards in 75 countries in the 1990s. I find that democracy leads to lower tariffs, higher core NTBs, and even higher quality NTBs. I conclude that democracy promotes “optimal obfuscation” that allows politicians to protect their markets while maintaining a veneer of liberalization.
Stacking the States, Stacking the House: The Partisan Consequences of Congressional Redistricting in the 19th Century
Authors: ENGSTROM ERIK J.
Published: September 2007

Considerable debate exists over the impact of redistricting on the partisan composition of the U.S. Congress. I address this debate by turning to an era of congressional redistricting that has received little systematic attention—the politics of gerrymandering in the 19th century. Using statewide-, county-, and ward-level electoral data from 1870 to 1900, I show that when a single party controlled the districting process, they used districting to systematically engineer a favorable partisan bias. These partisan biases affected the partisan composition of state congressional delegations and at times even helped determine party control of the House of Representatives.
Bringing Human Rights Home: An Examination of the Domestication of Human Rights Treaties in Nigeria
Authors: Egede Edwin
Published: September 2007

This article analyses the domestication of human rights treaties in Nigeria. It points out the shortcomings of the present dualist model under the 1999 constitution of the Federal Republic of Nigeria and makes suggestions for reform. It also examines the effect of beliefs and cultural values on the effective application of human rights treaties in Nigeria.
Genetic and environmental contributions to retrospectively reported DSM-IV childhood attention deficit hyperactivity disorder
Authors: Haberstick B. C. , Timberlake D. , Hopfer C. J. , Lessem J. M. , Ehringer M. A. , Hewitt J. K
Published: September 2007

Background

A variety of methodologies and techniques converge on the notion that adults and children with attention deficit hyperactivity disorder (ADHD) have similar deficits, but there is limited knowledge about whether adult retrospective reports reflect similar genetic and environmental influences implicated in childhood ADHD.

Method

DSM-IV ADHD symptoms were collected retrospectively from 3896 young adults participating in the National Longitudinal Study of Adolescent Health. Responses from this genetically informative sample of same- and opposite-sex twins and siblings were used to determine the magnitude of genetic and environmental influences. Possible gender differences in these effects were also examined. The degree of familial specificity of the genetic and environmental influences on the Inattentive and Hyperactive-Impulsive symptom dimensions was also determined.

Results

Additive genetic effects contributed moderately to DSM-IV Inattentive, Hyperactive-Impulsive and Combined ADHD subtypes (heritability estimates of 0.30–0.38). Individual-specific influences accounted for the remaining proportion of the variance. Both genetic and individual-specific environmental effects contributed to the covariation of Inattentive and Hyperactive-Impulsive symptomologies.

Conclusions

Results from our genetic analyses agree with previous findings based on self-assessment of current and retrospectively reported ADHD symptoms in adolescents and adults. Large individual-specific environmental influences as identified here suggest that current questionnaires used for retrospective diagnoses may not provide the most accurate reconstruction of the etiological influences on childhood ADHD in general population samples.
Social domain dysfunction and disorganization in borderline personality disorder
Authors: Hill J. , Pilkonis P. , Morse J. , Feske U. , Reynolds S. , Hope H. , Charest C. , Broyden N.
Published: September 2007

Background

Social dysfunction in personality disorder is commonly ascribed to abnormal temperamental traits but may also reflect deficits in social processing. In this study, we examined whether borderline and avoidant personality disorders (BPD, APD) may be differentiated by deficits in different social domains and whether disorganization of social domain functioning uniquely characterizes BPD.

Method

Patients were recruited from psychiatric clinics in Pittsburgh, USA, to provide a sample with BPD, APD and a no-personality disorder (no-PD) comparison group. Standardized assessments of Axis I and Axis II disorders and social domain dysfunction were conducted, including a new scale of ‘domain disorganization’ (DD).

Results

Pervasive social dysfunction was associated with a 16-fold increase in the odds of an Axis II disorder. Both APD and BPD were associated with elevated social dysfunction. Romantic relationship dysfunction was associated specifically with BPD symptoms and diagnosis. DD was associated specifically with a categorical BPD diagnosis and with a dimensional BPD symptom count.

Conclusions

A focus on the inherently interpersonal properties of personality disorders suggests specific mechanisms (within and across interpersonal domains) that may help to account for the origins and maintenance of some disorders. In particular, BPD reflects disturbances in romantic relationships, consistent with a role for attachment processes, and in the organization of functioning across social domains.
Long‐Term Maintenance of a Transgenic Catharanthus roseus Hairy Root Line
Authors: Peebles Christie A. M. , Gibson Susan I. , Shanks Jacqueline V. , San Ka‐Yiu
Published: September 2007

Stably transformed transgenic hairy root cultures have the potential to be a valuable production platform for a variety of secondary metabolites. This study reports that a transgenic hairy root culture of Catharanthus roseus has been stably maintained for over 4.5 years. This culture carries a transgene that expresses the green fluorescent protein under the control of the glucocorticoid‐inducible promoter. Genomic PCR confirmed the presence of the GFP insert within the hairy roots, and induction with dexamethasone caused a significant (p < 0.02) increase in GFP levels.
Der “Mere-Exposure”-Effekt und die Wahl von Produkten
Authors: Blüher Romy , Pahl Sabine
Published: September 2007

Zusammenfassung. Der “Mere-Exposure”-Effekt bezeichnet eine positive Einstellungsänderung gegenüber einem Reiz aufgrund der bloßen wiederholten Darbietung dieses Reizes ( Zajonc, 1968 ). In der vorliegenden Studie wurde geprüft, ob sich “mere exposure” auch auf tatsächliches Verhalten, nämlich die Auswahl von Produkten, auswirkt. Versuchspersonen (Vpn) sollten Sehenswürdigkeiten benennen, die auf Fotografien abgebildet waren. In zwei Experimentalbedingungen waren unauffällig zusätzlich Plakate zu sehen, die entweder das Logo eines Zitronenbonbons (“zitro”) oder eines Pfefferminzbonbons (“pfeffi”) zeigten; in einer Kontrollbedingung waren keine Plakate zu sehen. Später konnten die Vpn als Dankeschön zwischen den beiden Produkten wählen. Personen, die vorher zitro-Plakaten ausgesetzt waren, wählten - wie die Kontrollgruppe - mehrheitlich Zitronenbonbons, wohingegen sich diese Präferenz bei Personen, die vorher pfeffi-Plakaten ausgesetzt waren, umkehrte: sie wählten mehrheitlich Pfefferminzbonbons. Theoretische und praktische Implikationen werden diskutiert.
Possible reasons for underestimating Joule heating in global models: E field variability, spatial resolution, and vertical velocity
Authors: Deng Yue , Ridley Aaron J.
Published: September 2007

It is important to understand Joule heating because it can significantly change the temperature structure, atmosphere composition, and electron density and hence influences satellite drag. It is thought that many coupled ionosphere‐thermosphere models underestimate Joule heating because the spatial and temporal variability of the ionospheric electric field is not totally captured within global models. Using the Global Ionosphere Thermosphere Model (GITM), we explore the effect of the electric field temporal variability, model resolution, and vertical velocity differences between ion and neutral flows on Joule heating in a self‐consistent thermosphere/ionosphere system. First, the response of Joule heating to a step change in the externally driven electric field has been studied. While Joule heating is strongly affected by the convection electric field, both neutral winds and electron densities can significantly alter the spatial distribution of the Joule heating. Owing to the ramping up of neutral winds, there is a temporal variation of the Joule heating energy deposition rate when the electric field is constant. Second, we compare the calculated neutral gas heating rates when GITM is run with three different temporal variations of the electric fields, having the same temporally averaged electric field () but different standard deviations (σE). The neutral gas heating rate increases with the electric field temporal variability, and due to the feedback of the neutral winds and electron densities, the percentage increase is different from σE2/2, which is normally used to describe the effect of electric field temporal variability on the Joule heating. Third, comparison of the neutral gas heating rate with different model resolutions shows that at 200 km altitude, the polar average neutral gas heating rate increases by 20% when the latitudinal resolution increases from 5° to 1.25°. This is due to the model's ability to better capture small‐scale features in the electric field and particle precipitation. Last, inclusion of the vertical velocity difference (which is neglected in many models) is less significant than the other two factors and appears to be negligible at high latitudes. While the magnitude of the neutral gas heating rate at middle and low latitudes is smaller than that at high latitudes, the relative importance of the vertical velocity difference is larger, and the contribution can reach 15% of the averaged Joule heating at middle and low latitudes.
Localization of plastic zones in rocks around rigid inclusions: Insights from experimental and theoretical models
Authors: Misra Santanu , Mandal Nibir
Published: September 2007

Employing analogue and numerical experiments, we investigated the process of plastic creep in the vicinity of stiff inclusions and its role in the formation of shear zones. Analogue experiments were performed on Polymethylmethacrylate (PMMA) models in pure shear ( ≈ 10−4 s−1), which produced shear zones at a bulk strain >0.05. The geometrical dispositions of the shear zones do not conform to the stress concentration map derived from the plane theory of elasticity. At the initial stage (ɛb < 0.03), PMMA models began to deform plastically in four discrete strain localizations, tracking the stress concentration map. These incipient plastic locations develop a new stress field, diverting the zone of plastic yield in the form of multiple shear zones. Finite element models were run to demonstrate the formation of shear zones in this mode. The pattern of shear zones varied with the inclusion geometry. Inclusions of low aspect ratio (<1.5) gave rise to multiple sets of shear zones in their neighborhood. The multiplicity of shear zones tends to progressively decrease toward a single set of conjugate zones when the inclusions have relatively high aspect ratio (>2) and are oriented at an angle (>20°) to the bulk compression direction. Inclusions with a large aspect ratio (>4) developed a single dominant shear zone. The experimental findings can be compared to inclusion‐controlled shear zones from naturally deformed rocks.
Nonlinear single‐phase flow in real rock joints
Authors: Ranjith P. G. , Darlington W.
Published: September 2007

Laboratory analysis of single‐phase water and airflow through a real rock joint under increasing confining pressure was carried out in order to assess the linearity or otherwise of the Reynolds number (Re) versus pressure change relationship and to also test the applicability of Forchheimer's relation. These tests were conducted on a granitic specimen, 110 mm high and 55 mm in diameter, with a single natural fracture running the height of the specimen, which had a matrix permeability of approximately 10−18 m2. The single‐phase Re versus pressure change relationship using water was confirmed as being quadratic in nature. This same relationship held for single‐phase airflow but only for confining pressures below around 2.0 MPa. At confining pressures ≥3.0 MPa the relationship shifted in form to a cubic fit. In analyzing the application of Forchheimer's transmissivity relation to single‐phase water flow it was concluded that the model was appropriate for all tested confining pressures (0.55–3.0 MPa). When assessing its applicability to single‐phase airflow, the model was only accurate at low‐confining pressures (<1.0 MPa). Further, it was found that an increase in confining pressure shifted the Forchheimer's transmissivity curve downward.
Downscaling rainfall temporal variability
Authors: Marani Marco , Zanetti Stefano
Published: September 2007

A realistic description of land surface/atmosphere interactions in climate and hydrologic studies requires the specification of the rainfall forcing at aggregation scales of 1 hour or less. This is in contrast with the wide availability of daily rainfall observations and with the typically coarse output resolution of climate and numerical weather forecast models. Several methods have been devised to generate hourly or subhourly data from daily or monthly values, which usually rely on statistical regressions determined under the current climate conditions. Here we present a new method for downscaling rainfall in time using theoretically based estimates of rainfall variability at the hourly scale from daily statistics. The method is validated on a wide data set representative of different rainfall regimes and produces approximately unbiased estimates of rainfall variance at the hourly scale when a power law–tailed autocorrelation is assumed for the rainfall process. We further demonstrate how the downscaling method together with a Bartlett‐Lewis rainfall stochastic model may be used to generate hourly rainfall sequences that reproduce the observed small‐scale variability uniquely from daily statistics. Conclusions of a somewhat general nature are also drawn on the capability of finite memory stochastic models to reproduce the observed rainfall variability at different aggregation scales.
Propagating diurnal disturbances embedded in the Madden‐Julian Oscillation
Authors: Ichikawa Hiroki , Yasunari Tetsuzo
Published: September 2007

Fine structure of large‐scale intraseasonal disturbance associated with the Madden‐Julian Oscillation (MJO) was analyzed using the 3‐hourly (3B42) TRMM rainfall data. Over the Maritime Continent, diurnal cycle becomes pronounced during the passage of MJO, and the eastward propagating diurnal disturbances (PDDs) dominate as an internal structure of large‐scale convection system of MJO. Importantly, fast PDDs that penetrate through the islands are observed within the slowly propagating MJO system. This eastward penetration of PDDs through the islands result in a sudden shift of the convection center from the western part of the islands to the east, causing an overall propagation of the MJO from the Indian Ocean to the Pacific. Our results demonstrate that the diurnal cycle of convection over and around the major islands thus plays an active role in the propagation of the MJO over the Maritime Continent.
Predicted recovery of Mercury's internal structure by MESSENGER
Authors: Hauck Steven A. , Solomon Sean C. , Smith Derek A.
Published: September 2007

Recent Earth‐based and forthcoming MESSENGER spacecraft observations of the spin state and gravity field of Mercury will provide the opportunity to determine that planet's internal structure with unprecedented precision. These observations will provide estimates of the dimensionless polar moment of inertia and the ratio of the moment of inertia of the mantle plus crust to that of the planet. In order to understand how well these two parameters will constrain Mercury's internal structure we calculate ∼800,000 Monte Carlo models of the planet's interior. Within the uncertainties currently predicted to be achieved by MESSENGER for these quantities we estimate that the radius and bulk density of an Fe‐FeS core and the bulk density of the silicate shell can be determined to within ±23 km, ±147 kg m−3, and ±72 kg m−3, respectively.
Chemical behavior of the tropopause observed during the Stratosphere‐Troposphere Analyses of Regional Transport experiment
Authors: Pan L. L. , Bowman K. P. , Shapiro M. , Randel W. J. , Gao R. S. , Campos T. , Davis C. , Schauffler S. , Ridley B. A. , Wei J. C. , Barnet C.
Published: September 2007

During the Stratosphere‐Troposphere Analyses of Regional Transport (START) experiment in December 2005, the behavior of the extratropical tropopause was examined under a variety of dynamical conditions. Using in situ measurements of ozone and water vapor, on board the new NSF/NCAR research aircraft Gulfstream V, and data from large‐scale meteorological analyses, we address issues of the tropopause definitions and sharpness. Comparisons of the data from two flights show that the sharpness of chemical transitions across the tropopause varies with the sharpness of the static stability change across the tropopause. Using tracer correlations, air masses of mixed stratospheric and tropospheric characteristics are identified. The mixed air mass does not form a uniform mixing layer near the tropopause, but rather shows strong spatial variation. A depth of mixed air (∼5 km in vertical distribution) is found on the cyclonic side of the polar jet, where the thermal gradient is weak and significant separation occurs between the thermal and the dynamical tropopause. Away from the jet or on the anticyclonic side of the jet, where the stability gradient is strong, the chemical transition across the tropopause was much more abrupt and shows minimum mixing. In both cases (either significant or minimal mixing), the thermal tropopause is shown to be approximately at the center of the mixing layer, and the altitude relative to the thermal tropopause is found to be an effective coordinate for locating the chemical transition. To further understand the role of the thermal and dynamical tropopause as a chemical transport boundary, tracer correlations are used to examine the chemical characteristics, and the trajectory calculations are used to infer the fate of the air mass between the thermal and dynamic tropopauses in the region of significant separation. The tracer correlation analysis shows that the air mass in this region is a mixture of stratospheric and tropospheric air but predominantly of tropospheric characteristics. Trajectory model calculations show that a significant fraction of the air parcels in this region ended in the mid to lower troposphere, which suggest the irreversible nature of the observed stratospheric intrusion.
Impact of extended NAO buoyancy forcing on the subpolar North Atlantic and climate variability over the last millenium
Authors: Yang Duo , Myers Paul G.
Published: September 2007

We examine the impact of forcing a regional eddy‐permitting ocean model of the subpolar North Atlantic with anomalous buoyancy fluxes corresponding to extended extreme states of the North Atlantic Oscillation (NAO). We find a weakened (enhanced) Meridional Overturning Circulation (MOC) in our low (high) NAO simulations. Such results may be consistent with ideas that suggest the Medieval Warm Period (MWP) and the Little Ice Age are associated with periods when the NAO is predominantly in one phase. Our results also show multidecadal MOC variability with a period of 70 years in our high‐NAO simulation, in comparison to an equilibrium‐like circulation under low‐NAO related forcing. A less stable climatic state is therefore suggested to occur under high‐NAO forcing, which may be consistent with ideas that suggest the warming associated with the MWP did not occur synchronously over the North Atlantic. The variability appears to be brought about by internal oceanic processes.
Challenges in humid land ecohydrology: Interactions of water table and unsaturated zone with climate, soil, and vegetation
Authors: Rodriguez‐Iturbe Ignacio , D'Odorico Paolo , Laio Francesco , Ridolfi Luca , Tamea Stefania
Published: September 2007

Soil water content is a key determinant of the health of terrestrial ecosystems. It plays a fundamental role in the feedbacks between the Earth and the atmosphere, as well as in all aspects of vegetation growth and composition. The dynamics of soil water in humid areas, and especially in wetlands, presents particularly challenging features for its quantitative description, since it needs to be linked to the intertwined stochastic fluctuations of the water table and the soil moisture of the unsaturated zone. These fluctuations are themselves dependent on the climate, soil, and vegetation of the region. The paper describes some of the most important problems that need to be considered in attempting to develop a quantitative framework for the ecohydrology of humid areas. The avenues of research suggested here will play a keystone role in the understanding of the complex dynamics of humid lands as well as in their scientifically based management in the face of a changing climate.
Regulation of neurogenin stability by ubiquitin-mediated proteolysis
Authors: Vosper Jonathan M. D. , Fiore-Heriche Christelle S. , Horan Ian , Wilson Kate , Wise Helen , Philpott Anna
Published: September 2007

NGN (neurogenin), a proneural bHLH (basic helix–loop–helix) transcription factor, plays a central role in promoting neuronal specification and differentiation in many regions of the central nervous system. NGN activity has been shown extensively to be controlled at the transcriptional level. However, in addition, recent findings have indicated that the levels of NGN protein may also be regulated. In the present study, we have demonstrated that NGN protein stability was regulated in both Xenopus embryos and P19 embryonal carcinoma cells, a mammalian neuronal model system. In both systems, NGN was a highly unstable protein that was polyubiquitinated for destruction by the proteasome. NGN binds to DNA in complex with its heterodimeric E-protein partners E12 or E47. We observed that NGN was stabilized by the presence of E12/E47. Moreover, NGN was phosphorylated, and mutation of a single threonine residue substantially reduced E12-mediated stabilization of NGN. Thus E-protein partner binding and phosphorylation events act together to stabilize NGN, promoting its accumulation when it can be active.