bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glacier-dammed lake outburst events of Gornersee, Switzerland
Authors: Huss Matthias , Bauder Andreas , Werder Mauro , Funk Martin , Hock Regine 
Published: December 2007

AbstractGornersee, Switzerland, is an ice-marginal lake, which drains almost every year, subglacially, within a few days. We present an analysis of the lake outburst events between 1950 and 2005, as well as results of detailed field investigations related to the lake drainage in 2004 and 2005. The latter include measurements of lake geometry, water pressure in nearby boreholes and glacier surface motion. A distributed temperature-index melt model coupled to a linear-reservoir runoff model is used to calculate hourly discharge from the catchment of Gornergletscher in order to distinguish between the melt/precipitation component and the outburst component of the discharge hydrograph. In this way, drainage volume and timing are determined. From 1950 there is a clear trend for the outburst flood to occur earlier in the melt season, but there is no trend in lake discharge volumes. Peak discharges from the lake lie significantly below the values obtained using the empirical relation proposed by Clague and Mathews (1973). The shapes of the 2004 and 2005 lake outflow hydrographs differ substantially, suggesting different drainage mechanisms. From water balance considerations we infer a leakage of the glacier-dammed lake in 2005, starting 1 week prior to the lake outburst. During the drainage events, up to half of the lake water is temporarily stored in the glacial system, causing substantial uplift of the glacier surface.
Increased water storage at ice-stream onsets: a critical mechanism?
Authors: Bindschadler Robert , Choi Hyeungu 
Published: December 2007

AbstractThe interdependence of rapid ice flow, surface topography and the spatial distribution of subglacial water are examined by linking existing theories. The motivation is to investigate whether the acceleration of an ice-stream tributary contains a positive feedback that encourages the retention of subglacial water that leads to faster flow. Periodically varying surface and bed topographies are related through a linear ice-flow perturbation theory for various values of mean surface slope, perturbation amplitude and basal sliding speeds. The topographic variations lead to a periodic variation in hydraulic potential that is used to infer the tendency for subglacial water to be retained in local hydraulic potential minima. If water retention leads to enhanced basal sliding, a positive feedback loop is closed that could explain the transition from slower tributary flow to faster-streaming flow and the sustained downstream acceleration along the tributary–ice-stream system. A sensitivity study illustrates that the same range of topographic wavelengths most effectively transmitted from the bed to the surface also strongly influences the behavior of subglacial water. A lubrication index is defined to qualitatively measure the heterogeneity of the subglacial hydrologic system. Application of this index to field data shows that the transition from tributary to ice stream closely agrees with the location where subglacial water may be first stored.
Simulating complex snow distributions in windy environments using SnowTran-3D
Authors: Liston Glen E. , Haehnel Robert B. , Sturm Matthew , Hiemstra Christopher A. , Berezovskaya Svetlana , Tabler Ronald D. 
Published: December 2007

AbstractWe present a generalized version of SnowTran-3D (version 2.0), that simulates wind-related snow distributions over the range of topographic and climatic environments found globally. This version includes three primary enhancements to the original Liston and Sturm (1998) model: (1) an improved wind sub-model, (2) a two-layer sub-model describing the spatial and temporal evolution of friction velocity that must be exceeded to transport snow (the threshold friction velocity) and (3) implementation of a three-dimensional, equilibrium-drift profile sub-model that forces SnowTran-3D snow accumulations to duplicate observed drift profiles. These three sub-models allow SnowTran-3D to simulate snow-transport processes in variable topography and different snow climates. In addition, SnowTran-3D has been coupled to a high-resolution, spatially distributed meteorological model (MicroMet) to provide more realistic atmospheric forcing data. MicroMet distributes data (precipitation, wind speed and direction, air temperature and relative humidity) obtained from meteorological stations and/or atmospheric models located within or near the simulation domain. SnowTran-3D has also been coupled to a spatially distributed energy- and mass-balance snow-evolution modeling system (SnowModel) designed for application in any landscape and climate where snow is found. SnowTran-3D is typically run using temporal increments ranging from 1 hour to 1 day, horizontal grid increments ranging from 1 to 100 m and time-spans ranging from individual storms to entire snow seasons.
Remote sounding of Greenland supraglacial melt lakes: implications for subglacial hydraulics
Authors: Box Jason E. , Ski Kathleen 
Published: December 2007

AbstractA supraglacial lake-depth retrieval function is developed, based on the correspondence between moderate-resolution imaging spectroradiometer (MODIS) reflectance and water depth measured during raft surveys. Individual lake depth, area and volume statistics, including short-term temporal changes for Greenland’s southwestern ablation region, were compiled for 2000–05. The maximum area of an individual lake was found to be 8.9 km2, the maximum volume 53.0 × 106 m3 and the maximum depth 12.2 m, sampling over 0.0625 km2 pixel areas. The total lake volume reaches >1 km3 in this region by July each year. The importance of melt lake reservoirs to Greenland ice-sheet flow may be a feedback between abrupt lake drainage events and ice dynamics. Lake-outburst volumes up to 31.5 × 106 m3 d−1 are capable of providing sufficient water via moulins to hydraulically pressurize the subglacial environment. Since the overburden pressure at the base of a flooded moulin is greater than that provided by ice, lake-outburst events seem capable of exerting sufficient upward force to lift the ice sheet locally, if water flow in the subglacial environment is constrained laterally. Considering a moulin with a 10 m2 cross-sectional area, basal pressurization can be maintained over lake-outburst episodes lasting hours to days.
Effects of antiagglomerants on the interactions between hydrate particles
Authors: Anklam Mark R. , York J. Dalton , Helmerich Luke , Firoozabadi Abbas 
Published: December 2007

AbstractHydrate inbibition in natural gas production by antiagglomeration is promising because of effectiveness at high subcoolings encountered in many offshore operations. There are various mechanisms that are believed to contribute to the repulsion and attraction of hydrate particles. These include: (1) steric, (2) dispersion, (3) capillary, and (4) shear forces. Some of the expressions derived, and some formulas are used from the literature to provide a theoretical analysis of the forces between two hydrate particles to examine antiagglomeration using surfactants. Results show that hydrate particle size has the most important effect on antiagglomeration. Results also show that the contact angle increase and the oil‐water interfacial tension decrease will either reduce capillary forces significantly or eliminate it. Effective antiagglomerants reduce the size, decrease interfacial tension, and increase contact angle through the water phase. © 2007 American Institute of Chemical Engineers AIChE J, 2008
Leak growth mechanism in composite Pd membranes prepared by the electroless deposition method
Authors: Guazzone Federico , Ma Yi Hua 
Published: December 2007

AbstractThe leak (of He gas) in composite Pd membranes prepared by the electroless deposition method was studied. The leak was distributed over the entire surface of membranes, and was due to the formation of pinholes, 0.1–2 μm in dia., located at the boundaries of Pd clusters and Pd crystallites. The rate at which the leak developed in H2 atmosphere was determined at 450, 500 and 550°C, and an apparent activation energy for the leak growth was calculated to be equal to 238 kJ/mol, which was close to the activation energy of Pd self‐diffusion coefficient of 266 kJ/mol. From experimental data at 450, 500 and 550°C, the leak rate increase at 400°C was extrapolated. In order to corroborate the calculated rate at 400°C, a 4 μm thick composite Pd membrane, M‐53, was studied for over 2,000 h in H2 atmosphere. M‐53 showed a H2 permeance of 42 m3/m2 h bar0.5, and an outstanding selectivity (H2/He) higher than 22,000 over 2,200 h, which was in agreement with the calculated leak rate increase at 400°C. © 2007 American Institute of Chemical Engineers AIChE J, 2008
Association study of two polymorphisms of the serotonin‐2A receptor gene and suicide attempts
Authors: Vaquero‐Lorenzo Concepcion , Baca‐Garcia Enrique , Diaz‐Hernandez Montserrat , Perez‐Rodriguez M. Mercedes , Fernandez‐Navarro Pablo , Giner Lucas , Carballo Juan J. , Saiz‐Ruiz Jeronimo , Fernandez‐Piqueras Jose , Baldomero Enrique Baca , de Leon Jose , Oquendo Maria A. 
Published: December 2007

AbstractSerotonin (5‐HT) receptors may have a role in suicidal behavior. Previous studies have shown an association between the T102C polymorphism of the 5‐HT2a receptor gene and suicidal behavior. However, negative findings have also been reported. We examined the association between the T102C and C1354T (His452Tyr) polymorphisms of the 5‐HT2a receptor gene and suicide attempts. Four hundred forty‐one suicide attempters, 339 psychiatric patients, and 410 healthy controls were compared for genotypes of the T102C and C1354T (His452Tyr) polymorphisms. There were significant differences in the distribution of the three genotypes (TT, TC, and CC) of the T102C polymorphism in the three groups (controls, psychiatric patients, and suicide attempters). There was an excess of C/C genotypes in the suicide attempter group compared with the control group, but there were no significant differences between suicide attempters and psychiatric controls. We found no association between the C1354T polymorphism and suicide attempts. The C allele of the T102C polymorphism of the 5‐HT2A receptor gene may be associated with biological susceptibility for suicidal behavior or psychiatric conditions. © 2007 Wiley‐Liss, Inc.
New functional single nucleotide polymorphism (Ala72Ser) in the COMT gene is associated with aggressive behavior in male schizophrenia
Authors: Hong Jin Pyo , Lee Joongsun S. , Chung Seockhoon , Jung Jaeyeul , Yoo Hanik K. , Chang Sung Man , Kim Chang Yoon 
Published: December 2007

AbstractA new functional single nucleotide polymorphism (SNP) Ala72Ser in the COMT gene was discovered recently. The purpose of our study is to examine the association between Ala72Ser and Val158Met functional polymorphisms in COMT gene and homicidal behavior in schizophrenia. DNA was genotyped for the Ala72Ser and Val158Met SNPs of the COMT gene in a sample of 93 schizophrenic patients who committed homicide (H‐SCZ) and 100 schizophrenic patients who had never committed homicide (NH‐SCZ). A statistically significant difference was found in genotype distribution and allele frequencies in SNP Ala72Ser of COMT gene between H‐SCZ and NH‐SCZ group. In haplotype analysis, the frequency of the combination of high‐high activity allele (Ala‐Val) was lower in H‐SCZ group than in NH‐SCZ group (P = 0.000069). Our study showed a highly significant association between a COMT haplotype of two functional SNPs and aggressive behavior in schizophrenia. © 2007 Wiley‐Liss, Inc.
Family‐based SNP association study on 8q24 in bipolar disorder
Authors: Zandi Peter P. , Zöllner Sebastian , Avramopoulos Dimitrios , Willour Virginia L. , Chen Yi , Qin Zhaohui S. , Burmeister Margit , Miao Kuangyi , Gopalakrishnan Shyam , McEachin Richard , Potash James B. , DePaulo J. Raymond , McInnis Melvin G. 
Published: December 2007

AbstractPrevious linkage studies have identified chromosome 8q24 as a promising positional candidate region to search for bipolar disorder (BP) susceptibility genes. We, therefore, sought to identify BP susceptibility genes on chromosome 8q24 using a family‐based association study of a dense panel of SNPs selected to tag the known common variation across the region of interest. A total of 1,458 SNPs across 16 Mb of 8q24 were examined in 3,512 subjects, 1,954 of whom were affected with BP, from 737 multiplex families. Single‐locus tests were carried out with FBAT and Geno‐PDT, and multi‐locus test were carried out with HBAT and multi‐locus Geno‐PDT. None of the SNPs were associated with BP in the single‐locus tests at a level that exceeded our threshold for study‐wide significance (P < 3.00 × 10−5). However, there was consistent evidence at our threshold for the suggestive level (P < 7.00 × 10−4) from both the single locus and multi‐locus tests of associations with SNPs in the genes ADCY8, ST3GAL1, and NSE2. Multi‐locus analyses suggested joint effects between ADCY8 and ST3GAL1 (P = 3.00 × 10−4), with at least one copy of the “high risk” allele required at both genes for association with BP, consistent with a jointly dominant–dominant model of action. These findings with ADCY8 and ST3GAL1 warrant further investigation in order to confirm the observed associations and their functional significance for BP susceptibility. © 2007 Wiley‐Liss, Inc.
Association study between the serotonin 1A receptor (HTR1A) gene and neuroticism, major depression, and anxiety disorders
Authors: Hettema J.M. , An S.S. , van den Oord E.J.C.G , Neale M.C. , Kendler K.S. , Chen X. 
Published: December 2007

AbstractThe serotonin neurotransmitter system in general, and the serotonin 1A receptor in particular, has been broadly implicated in the pathophysiology of mood and anxiety disorders, although the results of genetic association studies have been mixed. In this study, we examined the serotonin 1A receptor gene, HTR1A, for its association with shared genetic risk across a range of anxiety and depression‐related phenotypes. Using multivariate structural equation modeling, we selected twin pairs from the population‐based Virginia Adult Twin Study of Psychiatric and Substance Use Disorders scoring at the extremes of a latent genetic risk factor that underlies susceptibility to neuroticism, major depression, and several anxiety disorders. One member from each selected pair was entered into a 2‐stage, case‐control association study for the HTR1A gene. In the resulting sample of 589 cases and 539 controls, four SNPs spanning the HTR1A locus, including the C(−1019)G functional promoter polymorphism (rs6295), were screened in stage 1, the positive results of which were tested for replication in stage 2. While one marker met threshold significance criteria in stage 1, this association was not replicated in stage 2. Post‐hoc analyses did not reveal association to any of the specific psychiatric phenotypes. Our data suggests that the HTR1A gene may not play a major role in the genetic susceptibility underlying depressive and anxiety‐related phenotypes. © 2007 Wiley‐Liss, Inc.
Two methylenetetrahydrofolate reductase gene (MTHFR) polymorphisms, schizophrenia and bipolar disorder: An association study
Authors: Jönsson Erik G , Larsson Kristina , Vares Maria , Hansen Thomas , Wang August G. , Djurovic Srdjan , Rønningen Kjersti S. , Andreassen Ole A. , Agartz Ingrid , Werge Thomas , Terenius Lars , Hall Håkan 
Published: December 2007

AbstractRecent meta‐analyses of the methylenetetrahydrofolate reductase gene (MTHFR) have suggested association between two of its functional single gene polymorphisms (SNPs; C677T and A1298C) and schizophrenia. Studies have also suggested association between MTHFR C677T and A1298C variation and bipolar disorder. In a replication attempt the MTHFR C677T and A1298C SNPs were analyzed in three Scandinavian schizophrenia case‐control samples. In addition, Norwegian patients with bipolar disorder were investigated. There were no statistically significant allele or genotype case‐control differences. The present Scandinavian results do not verify previous associations between the putative functional MTHFR gene polymorphisms and schizophrenia or bipolar disorder. However, when combined with previous studies in meta‐analyses there is still evidence for association between the MTHFR C677T polymorphism and schizophrenia. Additional studies are warranted to shed further light on these relationships. © 2007 Wiley‐Liss, Inc.
Replication of linkage with bipolar disorder on chromosome 16p in the eastern Quebec population
Authors: Mérette Chantal , Roy Marc‐André , Bureau Alexandre , Fournier Alain , Émond Claudia , Cliche Denis , Jomphe Valérie , Chagnon Yvon C. , Maziade Michel 
Published: December 2007

AbstractIn a previous study [Maziade et al. (2005); Mol Psychiatry 10:486–499], we provided evidence for linkage (parametric lod score of 4.05) on chromosome 16p for bipolar affective disorder (BP) in 21 kindreds from Eastern Quebec, a population characterized by a founder effect. Using a stringent design, we performed a replication study in a second sample of 27 kindreds (sample 2) collected from the same population and assessed with the same methodologies as in our original sample (sample 1), that is with the same diagnostic procedure and using a common set of 23 markers studied with model‐based (parametric) and model‐free (nonparametric) linkage analyses. We replicated our initial finding with P values <0.001. Indeed, maximum NPLall scores of 3.7 and 3.52 were found at marker D16S3060 in sample 2 for the narrow and broad BP phenotype definition, respectively. For the latter definition, the nonparametric score reached 3.87 in the combined sample, a value that exceeded the maximum NPL score obtained in each individual sample (NPLall = 2.32 in sample 1; NPLall = 3.52 in sample 2). Moreover, a refined phenotype restricted to BP associated with psychosis yielded significant evidence for linkage in each individual sample (NPLall = 2.38 in sample 1; NPLall = 2.72) while yielding the best result (NPLall score = 3.90) in the combined sample (samples 1 and 2), despite an important reduction in the number of affected individuals. It is also noteworthy that the use of the refined phenotype provided a location of the maximum linkage peak shared by both samples, that is, at marker D16S668 in 16p13.12, suggesting consistency across samples. Our study provided one of the strongest pieces of evidence for linkage with BP in 16p and illustrated the heuristic potential of a replication study in a second sample ascertained from the same population and using homogeneous methodologies. © 2007 Wiley‐Liss, Inc.
Study on GRIA2, GRIA3 and GRIA4 genes highlights a positive association between schizophrenia and GRIA3 in female patients
Authors: Magri Chiara , Gardella Rita , Valsecchi Paolo , Barlati Stefano Davide , Guizzetti Luca , Imperadori Laura , Bonvicini Cristian , Tura Gian Battista , Gennarelli Massimo , Sacchetti Emilio , Barlati Sergio 
Published: December 2007

AbstractImpairment of glutamatergic neurotransmission is one of the major hypotheses proposed to explain the neurobiology of schizophrenia. Therefore, the genes involved in the glutamate neurotransmitter system could be considered potential candidate genes for schizophrenia susceptibility. A systematic study on alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole‐propionic acid (AMPA) receptor genes has been carried out and the results obtained from the analysis on GRIA2, GRIA3 and GRIA4 are reported. No evidence of association with schizophrenia was found for the GRIA2 and GRIA4 genes; strong evidence of association with schizophrenia was found for GRIA3. This X‐linked gene showed a different behavior in the two genders; a positive association with schizophrenia was observed among females but not in males. Female carriers of rs1034428 A allele were found to have a 2.19‐fold higher risk of developing schizophrenia compared to non‐carriers and 3.28‐fold higher risk for developing a non‐paranoid phenotype. The analysis at the haplotype level showed that susceptibility to schizophrenia was associated with the specific haplotype rs989638–rs1034428–rs2227098 CAC (P = 0.0008). We conclude that, of the three AMPA genes analyzed here, only GRIA3 seems to be involved in the pathogenesis of schizophrenia, but only in females. © 2007 Wiley‐Liss, Inc.
Associations of ATF4 gene polymorphisms with schizophrenia in male patients
Authors: Qu Mei , Tang Fulei , Wang Lifang , Yan Hao , Han Yonghua , Yan Jun , Yue Weihua , Zhang Dai 
Published: December 2007

AbstractActivating transcription factor 4 (ATF4) is considered as a positional candidate gene for schizophrenia due to its location at chromosome 22q13, a region linked to schizophrenia. Furthermore, as protein interaction partner of ATF4, disrupted in schizophrenia 1 (DISC1) and its signal pathway implicated in the pathophysiology of schizophrenia have been widely supported by a number of genetic and neurobiological studies. Our aim was to investigate whether ATF4 is associated with schizophrenia in case–control samples of Han Chinese subjects consisting of 352 schizophrenia patients and 357 healthy controls. We detected 18 single nucleotide polymorphisms (SNPs) in ATF4 locus, two of which were analyzed, including one insertion at the putative core promoter region (rs17001266, –/C) and one nonsynonymous variant in exon 1 (rs4894, C/A, Pro22Gln). Allele distributions of two SNPs showed significant associations with schizophrenia in male subjects (respectively, rs17001266: P = 0.021, OR = 1.58, 95% CI = 1.07–2.33; rs4894: P = 0.004, OR = 1.78, 95% CI = 1.19–2.67), but not in female subjects as well as the entire population. Two haplotypes CC and ‐A constructed of rs17001266–rs4894 also revealed significant associations with schizophrenia in male group (global P = 0.0097). These findings support that ATF4 gene may be involved in susceptibility to schizophrenia with sex‐dependent effect in the Chinese Han population and suggest that further functional assays are needed to verify their relevance to the pathogenesis of schizophrenia. © 2007 Wiley‐Liss, Inc.
Association of the dopamine transporter gene and ADHD symptoms in a Canadian population‐based sample of same‐age twins
Authors: Ouellet‐Morin Isabelle , Wigg Karen G. , Feng Yu , Dionne Ginette , Robaey Philippe , Brendgen Mara , Vitaro Frank , Simard Louise , Schachar Russell , Tremblay Richard E. , Pérusse Daniel , Boivin Michel , Barr Cathy L. 
Published: December 2007

AbstractAttention deficit hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder emerging during childhood. Psychostimulant medications (e.g., methylphenidate) noticeably reduce ADHD symptoms in most children. Since methylphenidate inhibits dopamine transporter activity, the dopamine transporter gene (DAT1) was considered to be the prime candidate risk gene in ADHD. Several studies found evidence for an association between the 10‐repeat allele of the variable number of tandem repeat (VNTR) located in the 3′ untranslated region and ADHD and/or ADHD symptoms in clinical and population‐based samples. However, this finding was not replicated in all samples. In this study, we investigated the association between the DAT1 gene and ADHD symptoms in a population‐based twin sample from Québec (Canada). We used two polymorphisms, the VNTR and rs27072, the last providing the most significant results in a clinical sample from Toronto (Ontario, Canada). No association was noted between the VNTR and ADHD symptoms in children at 6 and 7 years of age, as reported by teachers. However, a significant association was found for the rs27072 polymorphism and symptoms of inattention and hyperactivity/impulsivity. These findings indicate that the DAT1 gene contributes to ADHD symptoms in this sample and further suggest that the VNTR may not be the optimal polymorphism for study in all populations. © 2007 Wiley‐Liss, Inc.