bluuebunny/crossref_metadata_2025_split huggingface dataset:
pH tolerances and regulatory abilities of freshwater and euryhaline Aedine mosquito larvae
Authors: Clark Thomas M. , Flis Benjamin J. , Remold Susanna K. 
Published: May 2004

SUMMARY
The pH regulatory abilities of two members of the mosquito tribe Aedini,known to have dramatically different saline tolerances, are investigated. The freshwater mosquito Aedes aegypti and the euryhaline Ochlerotatus taeniorhynchus tolerate very similar pH ranges. Both species complete larval development in waters ranging from pH 4 to pH 11, but naïve larvae always die in water of pH 3 or 12. Across the pH range 4–11, the hemolymph pH of O. taeniorhynchus is maintained constant while that of A. aegypti varies by 0.1 pH units. The salt composition of the water (3.5 g l–1 sea salt, 3.5 g l–1 NaCl,or nominally salt-free) has no effect on the range of pH tolerated by A. aegypti. In both species, the effects of pH on larval growth and development are minor in comparison with the influence of species and sex. Acclimation of A. aegypti to pH 4 or 11 increases survival times in pH 3 or 12, respectively, and allows a small percentage of larvae to pupate successfully at these extreme pH values. Such acclimation does not compromise survival at the other pH extreme.
Osmotic regulation in adultDrosophila melanogasterduring dehydration and rehydration
Authors: Albers Melissa A. , Bradley Timothy J. 
Published: May 2004

SUMMARYWe have examined the osmoregulatory capacities of laboratory populations of the insect Drosophila melanogaster by measuring hemolymph osmotic concentration during desiccation and upon recovery from a bout of desiccation. Recovery treatments entailed allowing the flies access to distilled water, a saline solution or a saline+sucrose solution after a desiccation bout shown to reduce hemolymph volume by ∼60%. Prior to desiccation, the hemolymph osmotic concentration was 353±11 mOsm. We found that Drosophila display strict osmotic regulation under prolonged conditions of dehydration. Osmotic regulation continued during recovery from desiccation, regardless of the fluid provided. This result is evidence that this insect does not require an external source of osmolytes or energy to regulate its hemolymph osmotic concentration or to restore hemolymph volume,which is reduced during desiccation. We also examined populations that have been selected for over 250 generations for enhanced desiccation resistance to identify physiological characters that have evolved in response to the selection regime. The selected lines displayed a reduced pre-desiccation hemolymph osmotic concentration (315±7 mOsm) and a marginally improved capacity for osmoregulation.
Preliminary characterization of two atypical soluble guanylyl cyclases in the central and peripheral nervous system ofDrosophila melanogaster
Authors: Langlais Kristofor K. , Stewart Judith A. , Morton David B. 
Published: May 2004

SUMMARYConventional soluble guanylyl cyclases form α/β heterodimers that are activated by nitric oxide (NO). Recently, atypical members of the soluble guanylyl cyclase family have been described that include the ratβ2 subunit and MsGC-β3 from Manduca sexta. Predictions from the Drosophila melanogaster genome identify three atypical guanylyl cyclase subunits: Gyc-88E (formerly CG4154), Gyc-89Da (formerly CG14885) and Gyc-89Db (formerly CG14886). Preliminary data showed that transient expression of Gyc-88E in heterologous cells generated enzyme activity in the absence of additional subunits that was slightly stimulated by the NO donor sodium nitroprusside (SNP) but not the NO donor DEA-NONOate or the NO-independent activator YC-1. Gyc-89Db was inactive when expressed alone but when co-expressed with Gyc-88E enhanced the basal and SNP-stimulated activity of Gyc-88E, suggesting that they may form heterodimers in vivo. Here,we describe the localization of Gyc-88E and Gyc-89Db and show that they are expressed in the embryonic and larval central nervous systems and are colocalized in several peripheral neurons that innervate trachea, basiconical sensilla and the sensory cones in the posterior segments of the embryo. We also show that there are two splice variants of Gyc-88E that differ by seven amino acids, although no differences in biochemical properties could be determined. We have also extended our analysis of the NO activation of Gyc-88E and Gyc-89Db, showing that several structurally unrelated NO donors activate Gyc-88E when expressed alone or when co-expressed with Gyc-89Db.
Relationship between the energetic cost of burrowing and genetic variability among populations of the pocket gopher,T. bottae: does physiological fitness correlate with genetic variability?
Authors: Hildner K. Kelly , Soulé Michael E. 
Published: May 2004

SUMMARYMany studies have reported relationships between genetic variability and fitness characters in invertebrates, but there is a paucity of such studies in mammals. Here, we use a statistically powerful paired sampling design to test whether the metabolic cost of burrowing, an important physiological trait in the pocket gopher, Thomomys bottae, correlates with genetic variability. Three pairs of pocket gopher populations were used, with each pair selected from a different subspecies and comprising one high genetic variability and one low genetic variability population. Genetic variability was measured using average allozyme heterozygosity and two measures of DNA fingerprint band sharing. In addition, the cost of burrowing for individuals from each population was determined from the oxygen consumption per gram of body mass per unit of work performed. Our results indicate that the cost of burrowing was significantly higher in populations with lower genetic variability (3-way ANCOVA, P=0.0150); mass-adjusted cost of burrowing in the low variability populations averaged 0.57±0.24 ml O2g–1 kgm–1 and that in the high variability populations averaged 0.42±0.19 ml O2 g–1kgm–1. The magnitude of the population differences in cost of burrowing was associated with the magnitude of difference in genetic variability. We conclude that population differences in genetic variability are reflected in physiological fitness differences for a trait that is essential to gopher survival.
Novel Plasma Methanol Decomposition to Hydrogen Using Corona Discharges
Authors: Li Hui-qing , Zou Ji-jun , Zhang Yue-ping , Liu Chang-jun 
Published: May 2004

Abstract
We reported in this work a simple, effective, and efficient hydrogen production from plasma methanol decomposition using DC and AC corona discharges at ambient condition. The highest hydrogen production rate was achieved with AC corona discharges. The power consumption was normally less than 0.02 Wh/Ncm3 H2. A major advantage of methanol decomposition using corona discharge is that only a very small discharge space is enough for sufficiently high decomposition.
Degradation of Methylene Blue on Carbonate Species-doped TiO2 Photocatalysts under Visible Light
Authors: Ohno Teruhisa , Tsubota Toshiki , Nishijima Kazumoto , Miyamoto Zenta 
Published: May 2004

Abstract
Carbonate (CO32−) species-doped titanium dioxide (TiO2) photocatalysts were prepared. By doping carbonate species into a TiO2 lattice, the absorption edge of TiO2 was largely shifted from 400 to 700 nm. Furthermore, methylene blue was photocatalytically decomposed at high efficiency on carbonate species-doped TiO2 photocatalysts under visible light at a wavelength longer than 550 nm.
Template Synthesis of Ag2S Nanorods via an Ion-exchange Route
Authors: Wang Zhenghua , Chen Xiangying , Zhang Meng , Qian Yitai 
Published: May 2004

Abstract
By using CdS nanorods as template, Ag2S nanorods were synthesized via a solution-phase ion-exchange route at room temperature. It is important to control a slow reaction speed by adding thiourea into the solution to form complex with Ag+ ion during the synthetic process.
Ciliary count in chronic suppurative otitis media: comparative quantitative study between mucosal and squamous types using scanning electron microscopy and image analysis
Authors: Atef Ahmed , Ayad Essam Ezat 
Published: May 2004

The objective of this study was to prove ciliary destruction in the middle-ear mucous membrane in cases of chronic suppurative otitis media (CSOM) and to compare both types of chronic suppurative otitis media with regard to the degree of ciliary destruction and ciliary count using objective quantitative techniques. The mucosa of the anterior mesotympanum over the promontory was sampled in 10 patients with mucosal CSOM and in another 10 patients with squamous type CSOM. Specimens were examined by scanning electron microscopy in combination with image analysis software techniques in order to study the
cilia under higher magnifications and to calculate the ciliary area. Five patients with otosclerosis, no history suggestive of otitis media and normal ear drum appearance served as controls. Samples were taken and studied at the Faculty of Medicine of Cairo University. CSOM was found to be associated with significant ciliary destruction and this was more evident in the squamous type than in the mucosal type.
Prevalence of external auditory canal exostoses in Australian surfboard riders
Authors: Hurst William , Bailey Michael , Hurst Benjamin 
Published: May 2004

This paper assessed 300 surfboard riders, comprising 229 males and 71 females to determine the prevalence and rate of growth of exostoses in this population. A group of cold water swimmers and a control group were also examined. Significant obstruction, defined as two thirds or more occlusion of the ear canal was noted in 90 of the male surfers and 10 female surfers. This degree of occlusion was found in seven of the 32 cold water swimmers. A male surfer who has surfed regularly for 20 years or more has a one in two chance of developing significant obstruction of the external ear canal resulting from exostoses and this is a three in seven chance for females.
A Likelihood Approach to Estimating Market Equilibrium Models
Authors: Draganska Michaela , Jain Dipak 
Published: May 2004

This paper develops a new likelihood-based method for the simultaneous estimation of structural demand-and-supply models for markets with differentiated products. We specify an individual-level discrete-choice model of demand and derive the supply side assuming manufacturers compete in prices. The proposed estimation method considers price endogeneity through simultaneous estimation of demand and supply, allows for consumer heterogeneity, and incorporates a pricing rule consistent with economic theory. The basic idea behind the proposed estimation procedure is to simulate prices and choice probabilities by solving for the market equilibrium. By repeating this many times, we obtain an empirical distribution of equilibrium prices and probabilities. The empirical distribution is then smoothed and used in a likelihood procedure to estimate the parameters of the model. The advantage of this method is that it avoids the need to perform a transformation of variables. If the tastes of consumers are independent across market periods, our approach yields maximum likelihood estimates; otherwise, it yields consistent but not fully efficient partial likelihood estimates.
Fatigue of Magnesium Alloys
Authors: Potzies C. , Kainer K.U. 
Published: May 2004

AbstractMagnesium alloys show a high specific strength and are therefore increasingly used for light‐weight constructions in transportation industry.[1,2] To predict the behaviour of the material under the influence of cyclic loading it is vital to understand the fatigue behaviour of magnesium alloys. Only when understood properly, it is possible to fully apply the potential weight reduction by using magnesium alloys. A very important aspect in fatigue of magnesium alloys is the influence of a corrosive media and elevated temperatures, of which both are relevant in automotive applications. These two factors tend to have deleterious effects on magnesium alloys and therefore also have to be considered in investigations on the fatigue behaviour of magnesium alloys.
Lack of relationship between CO2 reactivity and serotonin transporter gene regulatory region polymorphism in panic disorder
Authors: Perna Giampaolo , Bella Daniela di , Favaron Elisa , Cucchi Michele , Liperi Laura , Bellodi Laura 
Published: May 2004

AbstractChanges in the function of the serotonergic system influence both panic phobic symptoms and carbon dioxide (CO2) reactivity in patients with panic disorder. Schmidt et al. [2000: J Abnorm Psychol 109(2):308–320] recently reported a predictive role of the genetic variants of the 5‐HTTLPR on the fearful response to CO2 in healthy controls. We tested the hypothesis that the heterogeneity of CO2 reactivity in patients with panic disorder could be related to the allelic variation of the 5‐HTT promoter. Ninety‐five patients with panic disorder were challenged with 35% CO2. 5‐HTTLPR allelic variation in each subject was determined using a PCR‐based method. There were no differences for all the measures of CO2 reactivity among the genotype groups. CO2 reactivity of patients with panic disorder seems not to be influenced by the genetic variants of the 5‐HTTLPR; this finding does not support a role for the serotonin transporter in the etiopathogenesis of CO2 reactivity in panic disorder. © 2004 Wiley‐Liss, Inc.
ProtocadherinX/Y, a candidate gene‐pair for schizophrenia and schizoaffective disorder: A DHPLC investigation of genomic sequence
Authors: Giouzeli Maria , Williams Nic A. , Lonie Lorne J. , DeLisi Lynn E. , Crow Timothy J. 
Published: May 2004

AbstractProtocadherin X and Protocadherin Y (PCDHX and PCDHY) are cell‐surface adhesion molecules expressed predominantly in the brain. The PCDHX/Y gene‐pair was generated by an X–Y translocation approximately 3 million years ago (MYA) that gave rise to the Homo sapiens‐specific region of Xq21.3 and Yp11.2 homology. Genes within this region are expected to code for sexually dimorphic human characteristics, including, for example, cerebral asymmetry a dimension of variation that has been suggested is relevant to psychosis. We examined differences in patients with schizophrenic or schizoaffective psychosis in the genomic sequence of PCDHX and PCDHY in coding and adjacent intronic sequences using denaturing high performance liquid chromatography (DHPLC). Three coding variants were detected in PCDHX and two in PCDHY. However, neither the coding variants nor the intronic polymorphisms could be related to psychosis within families. Low sequence variation suggests selective pressure against sequence change in modern humans in contrast to the structural chromosomal and sequence changes including fixed X–Y differences that occurred in this region earlier in hominid evolution. Our findings exclude sequence variation in PCDHX/Y as relevant to the aetiology of psychosis. However, we note the unusual status of this region with respect to X‐inactivation. Further investigation of the epigenetic control of PCDHX/Y in relation to psychosis is warranted. © 2004 Wiley‐Liss, Inc.
New GABAA receptor alpha5 subunit gene polymorphism that may confound genotyping
Authors: Vaquero C. , Baca‐Garcia E. , Diaz‐Sastre C. , Perez‐Rodriguez M.M. , Navio Acosta M. , Saiz‐Ruiz J. , de Leon J. , Fernandez‐Piqueras J. 
Published: May 2004

AbstractWe report the discovery of a new GABAA receptor alpha5 subunit gene polymorphism close to the polymorphism described by Glatt et al. (GT)5GCGTGC(GT)21. This new polymorphism is of great importance, because it means that non‐denaturing acrylamide gels used to separate the different alleles of the polymorphism described by Glatt et al. cannot distinguish an allele with the sequence: (GT)4GCGTGC(GT)n from another allele with the sequence: (GT)4(GCGT)4GC(GT)n−6. These gel fragments are separated by size, which would be the same in these two cases. An alternative would be to use an analysis method that can detect base changes, for instance, single strand conformation polymorphism (SSCP) or denaturing gradient gel electrophoresis (DGGE). © 2004 Wiley‐Liss, Inc.
Lack of association between 5HT2A receptor gene haplotype, bipolar disorder and its clinical subtypes in a West European sample
Authors: Etain Bruno , Rousseva Angela , Roy Isabelle , Henry Chantal , Malafosse Alain , Buresi Catherine , Preisig Martin , Rayah Fadila , Leboyer Marion , Bellivier Frank 
Published: May 2004

AbstractBipolar affective disorder (BPAD) is a complex psychiatric disorder with a major genetic contribution. Abnormalities in serotonergic function have been implicated in its aetiology. The 5HT2A receptor (5HT2AR) gene is a strong candidate gene for involvement in BPAD, but previous association studies have reported conflicting results. These data are difficult to interpret because most negative results were obtained with small samples. The aim of this study was to test the association between the 5HT2AR gene and BPAD in a large West European sample. We studied the −1438G/A and the His452Tyr polymorphisms, for haplotype analysis to increase both informativity and the likelihood of detecting an association between BPAD and the 5HT2AR gene. We analysed the genotype, allele and haplotype distributions of two 5HT2AR gene variants in a population of 356 BPAD patients, which we compared with 208 healthy controls. We also carried out exploratory analysis in clinical subgroups of patients defined according to personal history of mood disorders, suicidal behaviour, comorbid psychiatric disorders and family history of affective disorders. We found no difference between BPAD patients and controls for allele, genotype and haplotype distributions. Exploratory analysis in subgroups of BPAD patients showed only a marginal difference in haplotype distribution between controls and BPAD patients with antidepressant‐induced mania (P = 0.018). This difference was not significant after correction for multiple testing. Our study suggests that the 5HT2AR gene is unlikely to be involved in genetic susceptibility to BPAD but should be further investigated in a pharmacogenetic study. © 2004 Wiley‐Liss, Inc.
Non‐replication of the brain‐derived neurotrophic factor (BDNF) association in bipolar affective disorder: A Belgian patient‐control study
Authors: Oswald Pierre , Del‐Favero Jurgen , Massat Isabelle , Souery Daniel , Claes Stephan , Van Broeckhoven Christine , Mendlewicz Julien 
Published: May 2004

AbstractThis patient‐control association study was conducted to investigate a possible association of two single nucleotide polymorphisms (SNPs), g.11757C > G and g.196G > A, in the brain‐derived neurotrophic factor (BDNF) with bipolar affective disorder (BPAD). Two hundred seventy‐five individuals of Belgian origin (at least two generations of Belgian ancestors) were genotyped (112 BPAD and 163 controls). No significant differences were found in the frequency of genotypes and alleles of g.196G > A (P = 0.37 and 0.94, respectively) and g.11757C > G (P = 0.49 and 0.59, respectively) between controls and BPAD patients. An haplotype analysis revealed no difference between patients and controls (P = 0.44). We failed to replicate previous findings implicating BDNF in the aetiology of BPAD. However, BDNF remains an interesting target for future genetic studies and should be tested in prospective pharmacogenetic therapeutic trials. © 2004 Wiley‐Liss, Inc.
Role of cerebral lateralization in control of immune processes in humans
Authors: Meador Kimford J. , Loring David W. , Ray Patty G. , Helman Sandra W. , Vazquez Blanca R. , Neveu Pierre J. 
Published: May 2004

AbstractCerebral lateralization may be important in neural control of immune function. Animal studies have demonstrated differential effects of left and right brain lesions on immune function, but human studies are inconclusive. Here, we show that resections in the language dominant hemisphere of patients with epilepsy reduce lymphocytes, total T cells, and helper T cells. In contrast, resections in the language nondominant hemisphere increased the same cellular elements. T‐cell responses to mitogens and microbial antigens were not differentially affected. Left/right arm histamine skin response ratios were altered in patients with left cerebral epileptic focus, and flare skin responses were reduced by left cerebral resections in contrast with an increase after right cerebral resections. The findings demonstrate a differential role of the left and right cerebral hemispheres on immune functions in humans. Ann Neurol 2004
The Belluš–Claisen Rearrangement
Authors: Gonda Jozef 
Published: May 2004

AbstractAmong the reactions available to synthetic chemists for the construction of new CC bonds, the Claisen rearrangement is one of the most powerful, elegant, and well‐characterized methods. A genuinely new variant, the Belluš–Claisen rearrangement came to light a quarter of a century ago: The reaction of an allylic ether, thioether, or amine with a ketene leads through a [3,3] sigmatropic bond reorganization of a zwitterionic intermediate to an E unsaturated ester, thioester, or amide. When applied to cyclic allylic substrates, a ring‐enlargement by four carbon atoms in one step provides medium‐ring unsaturated E‐configured lactones, thiolactones, and lactams. The scope of the Belluš–Claisen rearrangement and the optimum reaction conditions will be discussed in this Minireview.
Highly grafted polystyrene‐modified natural rubber as toughener for polystyrene
Authors: Neoh S. B. , Hashim Azanam S. 
Published: May 2004

AbstractA polystyrene‐modified natural rubber (SNR) with 80% degree of grafting was evaluated against natural rubber (NR) in their blends with polystyrene (PS). The rubber loading of the PS‐SNR and PS‐NR blends was varied from 5 to 20% by volume. At 10–15% rubber loading, the PS‐SNR blends were found to be approximately 8–10% higher in tensile strength and 7–13% higher in Young's modulus than the PS‐NR blends. Over the range of rubber loading investigated, it was also observed that the PS‐SNR blends were 5–42 and 14–36% higher in flexural strength and flexural modulus, respectively. The most pronounced difference between the two blend systems is in their impact strength, where the former is about 55–230% higher than the latter. Relative to the pure PS, the PS‐NR and PS‐SNR blends are approximately 50–250 and 140‐1050% higher, respectively, in impact strength. Morphological observations, which are consistent with the relative tensile, flexural, and impact properties of the two systems, indicate that SNR is more compatible with PS than NR and more homogeneously dispersed in the PS matrix. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1660–1665, 2004
Synthesis and humidity sensitivity of conducting polyaniline in SBA‐15
Authors: Li Nan , Li Xiaotian , Geng Wangchang , Zhang Tong , Zuo Yan , Qiu Shilun 
Published: May 2004

AbstractConducting polyaniline (PANI) was synthesized in mesoporous silica SBA‐15. The investigations of XRD, N2 adsorption–desorption, and IR spectra confirm the existence of polyaniline in the channels of SBA‐15 hosts. The impedance of PANI/SBA‐15 composites was studied at different relative humidity (RH) levels, ranging from 11 to 95% RH. The loadings of PANI as well as the concentration of HCl solution have substantial influence on the impedance values. The variation in impedance value of all PANI/SBA‐15 composites is more obvious than that of bulk PANI samples at the same RH. All these results imply that PANI/SBA‐15 composites may have better humidity‐sensitive properties than those of bulk PANI samples. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1597–1601, 2004