bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental split between germ cell parasitism and somatic cell synergism in chimeras of a colonial urochordate
Authors: Rinkevich Baruch , Yankelevich Irena
Published: August 2004

Colonies of the urochordate Botryllus schlosseri may fuse upon contact if they share common alleles on the highly polymorphic fusibility/histocompatibility locus. While, in these chimeras, one of the partners is usually morphologically eliminated (resorbed), circulating totipotent cells of the inferior genotype on the resorption phenomenon may parasitize either the soma or the germ line of the winner. Here, we show an environmental split of the two stem cell lineages that may develop germ cell parasitism vs somatic cell cooperation. Each naturally formed Botryllus chimera can be a composite of component genotypes created through two unlinked parasitic germ and somatic cell lineage interactions. The germ line parasitism is inherited through a pedigree. Conversely, by using amplified fragment length polymorphism (AFLP) and microsatellite alleles as polymorphic genetic markers, and seawater temperature as the variable environmental factor, we documented that the somatic constituent of chimeric zooids was shifted from one genotype to another, in accordance with the changes in seawater temperatures. This variable somatic state of chimerism in the field may, thus, carry benefits to the chimeral entity, which presents synergistically, at any time, the best-fitted combination of its genetic components.
Transmission of linearly polarized light in seawater: implications for polarization signaling
Authors: Shashar Nadav , Sabbah Shai , Cronin Thomas W.
Published: August 2004

Partially linearly polarized light is abundant in the oceans. The natural light field is partially polarized throughout the photic range, and some objects and animals produce a polarization pattern of their own. Many polarization-sensitive marine animals take advantage of the polarization information, using it for tasks ranging from navigation and finding food to communication. In such tasks, the distance to which the polarization information propagates is of great importance. Using newly designed polarization sensors, we measured the changes in linear polarization underwater as a function of distance from a standard target. In the relatively clear waters surrounding coral reefs, partial (%) polarization decreased exponentially as a function of distance from the target, resulting in a 50%reduction of partial polarization at a distance of 1.25–3 m, depending on water quality. Based on these measurements, we predict that polarization sensitivity will be most useful for short-range (in the order of meters)visual tasks in water and less so for detecting objects, signals, or structures from far away. Navigation and body orientation based on the celestial polarization pattern are predicted to be limited to shallow waters as well, while navigation based on the solar position is possible through a deeper range.
Acoustical stress and hearing sensitivity in fishes: does the linear threshold shift hypothesis hold water?
Authors: Smith Michael E. , Kane Andrew S. , Popper Arthur N.
Published: August 2004

Mammals exposed to loud aerial sounds exhibit temporary threshold shifts(TTS) that are linearly related to increases of sound pressure above baseline hearing levels. It was unknown if this relationship held true for aquatic ectotherms such as fishes. To test this linear threshold shift hypothesis(LINTS) in fishes, we examined the effects of increased ambient sound on hearing of two species differing in hearing capabilities: goldfish(Carassius auratus; a hearing specialist) and tilapia(Oreochromis niloticus; a hearing generalist). Fish were exposed to 1–28 days of either quiet (110 dB re 1 μPa) or continuous white noise. First, we examined the effect of noise sound pressure level (SPL; 130,140, 160 or 170 dB re 1 μPa) on goldfish hearing thresholds after 24 h of noise exposure. Second, in a long-term experiment using 170 dB re 1 μPa white noise, we continuously exposed goldfish and tilapia for either 7 or 21–28 days. In both experiments, we measured alterations in hearing capabilities (using auditory brainstem responses) of noise-exposed fish. While tilapia exposed to noise for 28 days showed little or no hearing loss,goldfish exhibited considerable threshold shifts that reached an asymptote of up to 25 dB after only 24 h of exposure. There was a positive linear relationship between noise-induced TTS and the sound pressure difference between the noise and the baseline hearing thresholds in goldfish but not in tilapia. A similar relationship was found for published noise-induced threshold shifts in birds and mammals, but the slope of the linear relationship was greater in these groups than for fish. The linear threshold shift relationship provides insights into differential susceptibility of hearing specialist and generalist fishes to noise-induced hearing loss for a given SPL and provides a framework for future research on noise-induced threshold shifts in fishes and other animals.
Plastic and evolved responses of larval tracheae and mass to varying atmospheric oxygen content inDrosophila melanogaster
Authors: Henry Joanna R. , Harrison Jon F.
Published: August 2004

Structural changes in the tracheal system during development have the potential to allow insects to compensate for varying oxygen availability. Despite possible compensation, oxygen level during development may also affect insect body size. We investigated how atmospheric oxygen level affects the dimensions of the main dorsal tracheae (DT) and masses of larval Drosophila melanogaster (Meigen) reared for up to six generations in 10%, 21% or 40% O2 at 25°C. Wandering-stage third-instar larvae were weighed every other generation, and the dimensions of the DT were measured. Hypoxia produced significantly lighter larvae after one generation of exposure, while hyperoxia did not affect larval mass. Atmospheric oxygen content did not significantly change the diameters of the anterior portions of the main tracheae; however, the posterior diameters were strongly affected. During the first generation of exposure, tracheal diameters were inversely proportional to rearing oxygen levels, demonstrating that developmental plasticity in DT diameters can partially (8–15%) compensate for variation in atmospheric oxygen level. After multiple generations in differing atmospheres and two further generations in 21% O2, larvae had tracheal diameters inversely related to their historical oxygen exposure,suggesting that atmospheric oxygen can produce heritable changes in insect tracheal morphology.
A cotranscriptional model for 3′-end processing of the Saccharomyces cerevisiae pre-ribosomal RNA precursor
Authors: HENRAS ANTHONY K. , BERTRAND EDOUARD , CHANFREAU GUILLAUME
Published: August 2004

Cleavage of the Saccharomyces cerevisiae primary ribosomal RNA (rRNA) transcript in the 3′ external transcribed spacer (ETS) by Rnt1p generates the 35S pre-rRNA, the earliest detectable species in the pre-rRNA processing pathway. In this study we show that Rnt1p is concentrated in a subnucleolar dot-shaped territory distinct from the nucleolar body. The 35S pre-rRNA is localized at the periphery of the Rnt1p dot, in a pattern that suggests a diffusion of the 35S pre-rRNA from the site of Rnt1p processing. When plasmid-borne versions of the rDNA are used to express rRNAs, the Rnt1p territory reorganizes around these plasmids, suggesting a close association between Rnt1p and the plasmid-borne rDNA units. Rnt1p was found associated with the endogenous rDNA by chromatin immunoprecipitation. Deletion of functionally important Rnt1p domains result in a loss of the dot-shaped territory, showing that this subnucleolar territory corresponds to a functional site of processing. These results show that a large fraction of Rnt1p is localized at the site of transcription of the rDNA, suggesting that the cleavage of the primary pre-rRNA transcript to generate the 35S pre-rRNA is a cotranscriptional event.
Intracellular folding of the Tetrahymena group I intron depends on exon sequence and promoter choice
Authors: KODUVAYUR SUJATHA P. , WOODSON SARAH A.
Published: August 2004

The Tetrahymena group I intron splices 20 to 50 times faster in Tetrahymena than in vitro, implying that the intron rapidly adopts its active conformation in the cell. The importance of cotranscriptional folding and the contribution of the rRNA exons to the stability of the active pre-RNA structure were investigated by comparing the activity of minimal pre-RNAs expressed in Escherichia coli. Pre-RNAs containing exons derived from E. coli 23 S rRNA were three to four times more active than the wild-type Tetrahymena pre-RNA. E. coli transcripts of the chimeric E. coli pre-RNA were two to eight times more active than were T7 transcripts. However, the effect of cotranscriptional folding depends on exon sequences. Unexpectedly, the unspliced pre-RNA decays more slowly than predicted from the rate of splicing. This observation is best explained by partitioning of transcripts into active and inactive pools. We propose that the active pool splices within a few seconds, whereas the inactive pool is degraded without appreciable splicing.
Frequency of catamenial seizure exacerbation in women with localization‐related epilepsy
Authors: Herzog Andrew G. , Harden Cynthia L. , Liporace Joyce , Pennell Page , Schomer Donald L. , Sperling Michael , Fowler Kristen , Nikolov Blagovast , Shuman Sevie , Newman Melanee
Published: August 2004

This investigation assessed the frequency of catamenial epilepsy in 87 women who charted seizures and menses during three cycles. Catamenial epilepsy designation was made if two of three cycles showed at least one of three previously defined catamenial patterns. Among ovulatory cycles, average daily seizure frequency was significantly greater during the perimenstrual and preovulatory phases. Among anovulatory cycles, average daily seizure frequency was substantially less during the midfollicular phase than during the remainder of the cycle. Overall, 39.1% of the women had catamenial epilepsy. Ann Neurol 2004;56:431–434
Mechanism of action of voltage‐gated K+ channel antibodies in acquired neuromyotonia
Authors: Tomimitsu Hisanori , Arimura Kimiyoshi , Nagado Tatsui , Watanabe Osamu , Otsuka Reika , Kurono Asutsugu , Sonoda Yoshito , Osame Mitsuhiro , Kameyama Masaki
Published: August 2004

Acquired neuromyotonia (ANM) is associated with antibodies to voltage‐gated K+ channels (VGKCs). ANM sera reduce the number of K+ currents in neuronal cell lines, but it is not clear how the antibodies act. Here, we show by using the NB‐1 cell line that the reduction in K+ currents by IgG is independent of added complement. IgG Fc and Fab fragments from ANM sera had no effect, but three of four ANM F(ab′)2 fragments significantly reduced K+ currents. Thus, cross‐linking of the channels by divalent antibodies is likely to be an important mechanism in reducing K+ currents. Ann Neurol 2004;56:440–444
Ganglioside complexes as new target antigens in Guillain–Barré syndrome
Authors: Kaida Ken‐ichi , Morita Daiji , Kanzaki Mami , Kamakura Keiko , Motoyoshi Kazuo , Hirakawa Minako , Kusunoki Susumu
Published: August 2004

Antibodies specific for a complex of gangliosides GD1a and GD1b (GD1a/GD1b) were found in sera from eight of 100 patients with Guillain–Barré syndrome (GBS) by the use of enzyme‐linked immunosorbent assay and thin‐layer chromatogram immunostaining. Those sera also had antibody activities to such ganglioside complexes as GD1a/GM1, GD1b/GT1b, and GM1/GT1b but had little or no reactivity to the each isolated antigen. Clustered epitopes of the ganglioside complex in the plasma membrane may be targeted by such an antibody, and interaction between the antibody and ganglioside complex may induce the neuropathy. Ann Neurol 2004
Homozygous PINK1 C‐terminus mutation causing early‐onset parkinsonism
Authors: Rohé Christan F. , Montagna Pasquale , Breedveld Guido , Cortelli Pietro , Oostra Ben A. , Bonifati Vincenzo
Published: August 2004

Two homozygous mutations in the PINK1 gene, encoding a mitochondrial putative protein kinase, recently have been identified in families with PARK6‐linked, autosomal recessive early‐onset parkinsonism (AREP). Here, we describe a novel homozygous mutation (1573_1574 insTTAG) identified in an AREP patient, which causes a frameshift and truncation at the C‐terminus of the PINK1 protein, outside the kinase catalytic domain. The clinical phenotype includes early‐onset (28 years) parkinsonism, foot dystonia at onset, good levodopa response, slow progression, early levodopa‐induced dyskinesias, and sleep benefit, thereby resembling closely parkin‐related disease. These findings confirm that recessive mutations in PINK1 cause early‐onset parkinsonism and expand the associated clinical phenotype. Ann Neurol 2004;56:427–431
Novel PINK1 mutations in early‐onset parkinsonism
Authors: Hatano Yasuko , Li Yuanzhe , Sato Kenichi , Asakawa Shuichi , Yamamura Yasuhiro , Tomiyama Hiroyuki , Yoshino Hiroyo , Asahina Masato , Kobayashi Susumu , Hassin‐Baer Sharon , Lu Chin‐Song , Ng Arlene R. , Rosales Raymond L. , Shimizu Nobuyoshi , Toda Tatsushi , Mizuno Yoshikuni , Hattori Nobutaka
Published: August 2004

PINK1 was recently found to be associated with PARK6 as the causative gene. We performed mutation analysis in eight inbred families whose haplotypes link to the PARK6 region. We identified six pathogenic mutations (R246X, H271Q, E417G, L347P, and Q239X/R492X) in six unrelated families. All sites of mutations were novel, suggesting that PINK1 may be the second most common causative gene next to parkin in parkinsonism with the recessive mode of inheritance. Ann Neurol 2004;56:424–427
Evaluation of the mechanical properties of sisal–polyester composites as a function of the polyester matrix formulation
Authors: Fonseca V. M. , Fernandes V. J. , de Carvalho L. H. , d'Almeida J. R. M.
Published: August 2004

In this work a comparative study on the impact and tensile properties of polyester/sisal fiber reinforced composites was undertaken. The polyester matrix was used bare and modified with: (1) a silane coupling agent; (2) a flame retardant system; and (3) a blend of the silane agent and the flame retardant system. The experimental results show that the flame retardant acts as a particulate reinforcement to the polyester matrix and the silane coupling agent acts as a plasticizer. The simultaneous addition of these two compounds to the polyester resin tended to decrease the performance of the composites. The results obtained show that strength or toughness could be tailored, and although none of the composites manufactured with the modified polyester matrices showed a significant improvement on the fiber–matrix interface strength, a better compromise between impact and tensile properties was obtained with the silane modified matrix. The critical fiber volume fraction was also evaluated and shown to be less than 10% for the sisal–polyester composite investigated here. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1209–1217, 2004
Interfacial interactions of a novel mechanochemical composite of cellulose with maleated polypropylene
Authors: Qiu Wulin , Endo Takashi , Hirotsu Takahiro
Published: August 2004

A novel composite was prepared by ball‐milling crystalline cellulose and maleic anhydride (MA) grafted polypropylene (MAPP) and its characteristics compared with a corresponding composite prepared by a conventional melt‐mixing method. The ball‐milling induces the formation of more ester bonds between cellulose and MAPP. The resulting MAPP chains bound to particles of cellulose, which created much stronger interfacial adhesion between the cellulose particles and the MAPP matrix. Accordingly, such enhanced interfacial adhesion substantially differentiates the mechanochemically prepared composite from the melt‐mixed composite. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1326–1335, 2004
CDK1‐Inhibitory Activity of Paullones Depends on Electronic Properties of 9‐Substituents
Authors: Pies Tanja , Schaper Klaus‐Jürgen , Leost Maryse , Zaharevitz Daniel W. , Gussio Rick , Meijer Laurent , Kunicke Conrad
Published: August 2004

Multiple linear regression analysis was employed in an effort to establish a quantitative structure‐activity relationship model for the CDK1‐inhibitory activity of a series of 9‐substituted paullones. While the electronic properties of the 9‐substituents proved to be of high relevance for CDK1 inhibition, both lipophilic and a steric parameters could not be included in a meaningful equation for the calculation of biological properties. The equation solely based on the electronic parameter was successfully used for the prediction of the CDK1‐inhibitory activity of a small test set comprising novel paullones with sulfur‐containing 9‐substituents. Among these new derivatives, 2‐methoxy‐9‐methylsulfonylpaullone proved to be superior to the standard alsterpaullone with respect to CDK1 inhibition.
Chinese version of the M. D. Anderson Symptom Inventory
Authors: Wang Xin Shelley , Wang Ying , Guo Hong , Mendoza Tito R. , Hao Xi‐Shan , Cleeland Charles S.
Published: August 2004

BACKGROUND

Symptom management is an essential component of cancer treatment for patients of every culture and nationality. Symptom assessment depends on subjective reporting, mandating linguistically equivalent versions of symptom assessment scales. Because disease‐related and treatment‐related symptoms most often occur in clusters, there is a global need for a standardized multiple‐symptom assessment tool.

METHODS

The authors sought to validate the Chinese version of the M. D. Anderson Symptom Inventory (MDASI‐C) by enrolling patients who had received various diagnoses of and different types of treatment for cancer (n = 249) in a cross‐sectional symptom study conducted at an urban cancer center in China.

RESULTS

Factor analysis identified 2 underlying constructs, general symptoms and gastrointestinal symptoms, which had Cronbach alpha coefficients of 0.86 and 0.84, respectively. These results were consistent with English‐ and Japanese‐language MDASI validation studies. Known‐group validity was supported by the MDASI‐C's ability to detect significant differences in symptom and interference levels according to Eastern Cooperative Oncology Group performance status (ECOG PS; P < 0.001) and chemotherapy status (P < 0.05). Fifty‐five percent of the study cohort had ≥ 1 symptom that was considered severe (score ≥ 7 on a 0–10 scale). ECOG PS was strongly associated with symptom burden (total interference score: R2 = 0.26; P < 0.001). Fatigue, sadness, drowsiness, and lack of appetite accounted for most of the variability in the total interference score (R2 = 0.49; P < 0.05).

CONCLUSIONS

The authors demonstrated that the MDASI‐C is a valid, reliable, and concise tool for measuring symptom severity and interference with functioning in Chinese cancer patients. Cancer 2004. © 2004 American Cancer Society.
The relationship between breast density and bone mineral density in postmenopausal women
Authors: Buist Diana S. M. , Anderson Melissa L. , Taplin Stephen H. , LaCroix Andrea Z.
Published: August 2004

BACKGROUND

It is not well understood whether breast density is a marker of cumulative exposure to estrogen or a marker of recent exposure to estrogen. The authors examined the relationship between bone mineral density (BMD; a marker of lifetime estrogen exposure) and breast density.

METHODS

The authors conducted a cross‐sectional analysis among 1800 postmenopausal women ≥ 54 years. BMD data were taken from two population‐based studies conducted in 1992–1993 (n = 1055) and in 1998–1999 (n = 753). The authors linked BMD data with breast density information collected as part of a mammography screening program. They used linear regression to evaluate the density relationship, adjusted for age, hormone therapy use, body mass index (BMI), and reproductive covariates.

RESULTS

There was a small but significant negative association between BMD and breast density. The negative correlation between density measures was not explained by hormone therapy or age, and BMI was the only covariate that notably influenced the relationship. Stratification by BMI only revealed the negative correlation between bone and breast densities in women with normal BMI. There was no relationship in overweight or obese women. The same relationship was seen for all women who had never used hormone therapy, but it was not significant once stratified by BMI.

CONCLUSIONS

BMD and breast density were not positively associated although both are independently associated with estrogen exposure. It is likely that unique organ responses obscure the relationship between the two as indicators of cumulative estrogen exposure. Cancer 2004. © 2004 American Cancer Society.
Distribution and development of glutamic acid decarboxylase immunoreactivity in the spinal cord of the dogfish Scyliorhinus canicula (elasmobranchs)
Authors: Sueiro Catalina , Carrera Iván , Molist Pilar , Rodríguez‐Moldes Isabel , Anadón Ramón
Published: August 2004

The adult distribution and development of γ‐aminobutyric acid (GABA)‐synthesizing cells and fibers in the spinal cord of the lesser spotted dogfish (Scyliorhinus canicula L.) was studied by means of immunohistochemistry using antibodies against glutamic acid decarboxylase (GAD). Complementary immunostaining with antibodies against GABA, tyrosine hydroxylase (TH), and HuC/HuD (members of the Hu/Elav family of RNA‐associated proteins) and staining with a reduced silver procedure (“en bloc” Bielschowski method), Nissl, and hematoxylin were also used. In adults, GAD‐immunoreactive (GAD‐ir) cells were observed in the ventral horns, in the spinal nucleus of the dorsal horn, at the base of the dorsal horns, and around the central canal, where some GAD‐ir cells were cerebrospinal fluid‐contacting (CSF‐c). In addition, a few GAD‐ir cells were observed in the lateral funiculus between the ventral horn and the marginal nucleus. The adult spinal cord was richly innervated by GAD‐ir fibers. Large numbers of GAD‐ir fibers and boutons were observed in the dorsal and ventral horns and also interstitially in the dorsal, lateral, and ventral funiculi. In addition, a rich GAD‐ir innervation was observed in the marginal nucleus of the spinal cord. In the embryonic spinal cord, GAD‐ir cells develop very early: The earliest cells were observed in the very thin mantle/marginal layer of stage 22 embryos in a short length of the spinal cord. At stages 25 and 26, several types of GAD‐ir cells (commissural and noncommissural) were distinguished, and two of these cells were of CSF‐c type. At stages 28, 30, and 31, the GAD‐ir populations exhibited a marked longitudinal columnar organization. Double‐immunolabeling experiments in embryos showed the presence of two different GAD‐ir CSF‐c cell populations, one ventral that is simultaneously TH‐ir and other more dorsal that is TH‐negative. By stage 33 (prehatching), GAD‐expressing cells are present in virtually all loci, as in adults, especially in the ventral horn and base of the dorsal horn. The present results for the lesser spotted dogfish suggest an important role for γ‐aminobutyric acid in sensory and motor circuits of the spinal cord. J. Comp. Neurol. 478:189–206, 2004. © 2004 Wiley‐Liss, Inc.
Thermodynamic Properties and Plasma Phase Transition in dense Hydrogen
Authors: Filinov V. S. , Bonitz M. , Fortov V. E. , Ebeling W. , Levashov P. , Schlanges M.
Published: August 2004

The internal energy and equation of state of dense hydrogen are investigated by direct path integral Monte Carlo method simulations which are further improved in comparison to our previous results. Data for four isotherms –T= 10, 000K, 30, 000K, 50, 000K, and 100, 000K – are presented. ForT= 10, 000K it is shown that the internal energy is lowered due to droplet formation for densities of the order 1023cm–3giving direct support for the existence of a plasma phase transition in megabar hydrogen. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A Decade of Aerothermal Plasma Research at the von Karman Institute
Authors: Bottin B. , Carbonaro M. , Chazot O. , Degrez G. , Vanden Abeele D. , Barbante P. , Paris S. , Van Der Haegen V. , Magin Th. , Playez M.
Published: August 2004

The paper presents an overview of the aerothermal plasma simulation facilities in use at the von Karman Institute for Fluid Dynamics and the main research topics that have been followed during 10 years of work in the field. Both numerical simulation of plasma flows and experimental techniques are addressed, with an emphasis of the methodology which allows to relate measurements in the facilities to flight conditions of a space vehicle (re‐)entering a planetary atmosphere. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isotope Effect of H–/D– Volume Production in Low‐Pressure H2/D2 Plasmas – Measurement of VUV Emissions and Negative Ion Densities
Authors: Fukumasa O. , Mori S. , Nakada N. , Tauchi Y. , Hamabe M. , Tsumori K. , Takeiri Y.
Published: August 2004

Isotope effect on H–/D– volume production is studied by measuring both VUV emission and negative ion density in the source. In a double plasma type source, under some discharge conditions, extracted D– currents are nearly the same as H– currents, although VUV emission intensity (corresponding to production of vibrationally excited molecules) in D2 plasmas is slightly lower than that in H2 plasmas. Considering the factor √2 due to mass difference, D– ion density in the extraction region of the source is higher than H– ion density. In another experiment with a rectangular arc chamber, axial distributions of H–/D– ion densities in the source are measured directly using a laser photodetachment method. Relationship between H–/D– production and plasma parameter control with using a magnetic filter (MF) is discussed. Furthermore, relative intensities of extracted negative ion currents are discussed compared with the negative ion densities in the source. Production and control of D2 plasmas are well realized with the MF including good combination between the filament position and field intensity of the MF. Extracted H– and D– currents depend directly on negative ion densities in the source. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prospects of Phase Resolved Optical Emission Spectroscopy as a Powerful Diagnostic Tool for RF‐Discharges
Authors: Gans T. , Schulz‐von der Gathen V. , Döbele H. F.
Published: August 2004

Phase resolved optical emission spectroscopy (PROES) bears considerable potential for diagnostics of RF discharges that give detailed insight of spatial and temporal variations of excitation processes. Based on phase and space resolved measurements of the population dynamics of excited states several diagnostic techniques have been developed. Results for a hydrogen capacitively coupled RF (CCRF) discharge are discussed as an example. The gas temperature, the degree of dissociation and the temporally and spatially resolved electron energy distribution function (EEDF) of energetic electrons (>12eV) are measured. Furthermore, the pulsed electron impact excitation during the field reversal phase, typical for hydrogen CCRF discharges, is exploited for measurements of atomic and molecular data like lifetimes of excited states, coefficients for radiationless collisional de‐excitation (quenching coefficients), and cascading processes from higher electronic states. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Large Volume Atmospheric Pressure Glow Discharges
Authors: Leys C.
Published: August 2004

A review is given of recent progress in generating large volume glow discharges at atmospheric pressure. A number of applications will be highlighted, along with the issues that need to be resolved in order to meet the criteria for industrial acceptance. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Guided‐Wave‐Produced Plasmas
Authors: Koleva I. , Makasheva K. , Paunska Ts. , Schlüter H. , Shivarova A. , Tarnev Kh.
Published: August 2004

A review on recent development in self‐consistent description of high‐frequency discharges is presented. The discussions are based on fluid models of travelling‐wave‐sustained plasmas and results for the axial structure of discharges in different gases. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Magnetised Plasma‐Wall Transition: Theory and PIC Simulation
Authors: Tskhakaya D. , Kuhn S.
Published: August 2004

We consider the plasma‐wall boundary conditions in the presence of a strong magnetic field and discuss realistic examples when they can strongly deviate from the well‐accepted classical ones. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evaluation of NMP179 for the detection of squamous intraepithelial neoplasia in ThinPrep cervical slides using a combination of double immunostaining and morphometric methods of analysis
Authors: Al‐Awadhi Rana , Van Noorden Susan , V. Coleman Dulcie
Published: August 2004

This study investigates the potential value of the nuclear matrix protein NMP179 as a marker of abnormal squamous cells in ThinPrep slides. Forty‐six cervical scrapes were collected as cell suspensions and ThinPrep slides were prepared. They were double‐immunostained for NMP179 and Cytokeratin 18 (CK18), an endocervical cell marker. The method of analysis adopted for the study was designed to distinguish the abnormal squamous cells from benign epithelial cell so that the percentages of abnormal squamous cells that expressed the marker could accurately be determined. Initially, an attempt was made to identify benign and abnormal cells in the ThinPrep slides on the basis of their morphology and immunostaining patterns. Discrimination between the various types of epithelial cells was incomplete using this approach and a more precise method of discrimination between the different epithelial cell types was carried out using a combination of double immunostaining (NMP179 and CK18) and morphometry using nuclear area and nuclear cytoplasmic ratios. Once the different epithelial cell types had been identified, the specificity and sensitivity of NMP179 were determined. The optimal sensitivity (89.9%) was achieved at the N/C ratio 0.36; however, the specificity of NMP179 was very low for all N/C ratios and ranged from 38.8% to 42.2%. Diagn. Cytopathol. 2004;31:135–140. © 2004 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology findings from a case of pancreatic heterotopia at the gastroesophageal junction
Authors: Rodriguez Fausto J. , Abraham Susan C. , Allen Mark S. , Sebo Thomas J.
Published: August 2004

Pancreatic heterotopia is a well‐recognized entity occurring at a variety of sites in the gastrointestinal tract. However, only a handful of patients have been described with this abnormality at the gastroesophageal junction. Cytologic descriptions of pancreatic heterotopia in general are scant in the literature. We report the cytologic findings of ectopic pancreatic tissue at the gastroesophageal junction in a 41‐year‐old female, which was initially identified by endoscopic ultrasound and fine‐needle aspiration. Cytologic examination of Papanicolaou‐stained smears revealed clusters of benign‐appearing ducts and small acini mixed with inflammatory cells. Hematoxylin and eosin staining of the Tru‐Cut biopsy revealed benign pancreatic tissue. The patient underwent surgical resection due to symptoms related to inflammation of the heterotopic pancreatic tissue. The increasing use of endoscopic ultrasound and fine‐needle aspiration for the diagnosis of gastrointestinal tumors makes the recognition of pseudoneoplastic lesions at unusual sites an important step in optimum patient management. Diagn. Cytopathol. 2004;31:175–179. © 2004 Wiley‐Liss, Inc.
Characteristics method with cubic‐spline interpolation for open channel flow computation
Authors: Tsai Tung‐Lin , Chiang Shih‐Wei , Yang Jinn‐Chuang
Published: August 2004

In the framework of the specified‐time‐interval scheme, the accuracy of the characteristic method is greatly related to the form of the interpolation. The linear interpolation was commonly used to couple the characteristics method (LI method) in open channel flow computation. The LI method is easy to implement, but it leads to an inevitable smoothing of the solution. The characteristics method with the Hermite cubic interpolation (HP method, originally developed by Holly and Preissmann, 1977) was then proposed to largely reduce the error induced by the LI method. In this paper, the cubic‐spline interpolation on the space line or on the time line is employed to integrate with characteristics method (CS method) for unsteady flow computation in open channel. Two hypothetical examples, including gradually and rapidly varied flows, are used to examine the applicability of the CS method as compared with the LI method, the HP method, and the analytical solutions. The simulated results show that the CS method is comparable to the HP method and more accurate than the LI method. Without tackling the additional equations for spatial or temporal derivatives, the CS method is easier to implement and more efficient than the HP method. Copyright © 2004 John Wiley & Sons, Ltd.
A combined fictitious domain/adaptive meshing method for fluid–structure interaction in heart valves
Authors: van Loon R. , Anderson P. D. , de Hart J. , Baaijens F. P. T.
Published: August 2004

A new approach for modelling the fluid‐structure interaction of flexible heart valves is proposed. Using a finite element method, a Lagrangian description of a non‐linear solid and an Eulerian description of a fluid are coupled by a Lagrange multiplier. This multiplier allows the solid and fluid mesh to be non‐conform. Solid displacements and fluid velocities are described well in such a fictitious domain approach. However, the accuracy of pressures and shear stresses in the vicinity of the solid are poor. Therefore an inexpensive mesh‐adaptation algorithm is applied, which adapts the fluid mesh to the position of the solid mesh every time step. This minor adjustment of the fluid mesh makes it possible to sustain a physiological pressure gradient across a solid leaflet. Furthermore, shear stresses can be computed at both sides of the leaflet. The method is demonstrated for a 2D example, however with a scope to 3D modelling. Copyright © 2004 John Wiley & Sons, Ltd.
Inter‐rater and test–retest reliability of three contingent valuation question formats in south‐east Nigeria
Authors: Onwujekwe Obinna , Fox‐Rushby Julia , Hanson Kara
Published: August 2004

This paper examines the inter‐rater and test–retest reliability of willingness to pay (WTP) for insecticide‐treated mosquito nets and net re‐treatment using the bidding game (BG), binary with follow‐up (BWFU) and a novel structured haggling technique (SH). Inter‐rater reliability was evaluated by having two sets of interviewers administer questionnaires to 109 (BG), 110 (BWFU) and 103 (SH) randomly selected household heads. Test–retest reliability was investigated by repeating interviews on 146 (BG), 161 (BWFU) and 139 (SH) household heads one month after an initial survey. Data analysis used testing of means, Spearman's correlation and Pearson's correlation coefficient for test of reliability, while non‐parametric analysis was used to determine factors causing a variation in WTP. The study was conducted in Southeast Nigeria. Inter‐rater reliability coefficients were estimated for the individual's WTP for own nets, WTP for others and WTP for re‐treatment. Using WTP for own nets as the best reliability estimate, the coefficients were high at values of 0.77 (C.I. 0.72–0.86), 0.75 (C.I. 0.64–0.81) and 0.74 (C.I. 0.63–0.82) in the BG, BWFU and SH, respectively. In test–retest reliability coefficients, the coefficients for WTP for own nets were low‐to‐moderate at values of 0.51 (C.I. 0.40–0.62), 0.41 (C.I. 0.28–0.53) and 0.56 (C.I. 0.41–0.65) for the BG, BWFU and SH groups, respectively. Factors such as gender, change in income, unplanned expenditures, stated WTP in first survey, time‐to‐think, external information, and subjecting respondents to more than one interview explained the lower test–retest reliability coefficients. We conclude that the CVM was reliable in the study area and the question formats had similar levels of reliability. The lower coefficients in the test–retest reliability were due to the influence of factors affecting demand that had changed in the intervening period. Standard formats for determining reliability within CVM should be developed for easy comparison of results from different studies. Copyright © 2004 John Wiley & Sons, Ltd.
Large changes in cytoplasmic biopolymer concentration with osmolality indicate that macromolecular crowding may regulate protein–DNA interactions and growth rate in osmotically stressed Escherichia coli K‐12
Authors: Cayley Scott , Record M. Thomas
Published: August 2004

From determination of amounts and concentrations of biopolymers and solutes in the cytoplasm of Escherichia coli, we are obtaining information needed to assess the effect of macromolecular crowding on cytoplasmic properties and processes of osmotically stressed bacteria. We observe that growth rate, and the amount of cytoplasmic water decrease and cytoplasmic concentrations of biopolymers and K+, increase with increasing osmolality, even for cells grown in the presence of osmoprotectants like glycine betaine. We observe general correlations between the amount of cytoplasmic water, growth rate and cytoplasmic K+ concentration in osmotically stressed cells grown both with and without osmoprotectants. To explain these correlations, we propose that crowding increases with increasing growth osmolality, which in turn buffers the binding of proteins to nucleic acids against changes in cytoplasmic K+ concentration and (by affecting biopolymer diffusion rates and/or assembly equilibria) is a determinant of growth rate of osmotically stressed cells. Changes in biopolymer concentration and crowding may also explain the increase of the activity coefficient of cytoplasmic water with increasing osmolality of growth in E. coli. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of molecular crowding on self‐association of phosphorylase kinase and its interaction with phosphorylase b and glycogen
Authors: Chebotareva Natalia A. , Andreeva Iraida E. , Makeeva Valentina F. , Livanova Natalia B. , Kurganov Boris I.
Published: August 2004

Self‐association of phosphorylase kinase (PhK) and its interaction with glycogen (M=5500 kDa) and phosphorylase b (Phb) has been studied using analytical ultracentrifugation and turbidimetry under the conditions of molecular crowding arising from the presence of high concentrations of osmolytes. In accordance with the predictions of the molecular crowding theory, trimethylamine N‐oxide (TMAO) and betaine greatly favor self‐association of PhK induced by Mg2+ and Ca2+ and PhK interaction with glycogen. In contrast, proline suppresses these processes, probably, due to its specific interaction with PhK. All osmolytes tested prevented the complex formation between PhK and its physiological substrate, Phb. The specific interactions of PhK and Phb with glycogen, in the living cell, presumably is a factor allowing the negative effect of crowding on the recognition of Phb by PhK to be overcome. Copyright © 2004 John Wiley & Sons, Ltd.
Crowding and the polymerization of sickle hemoglobin
Authors: Ferrone Frank A. , Rotter Maria A.
Published: August 2004

Under physiological conditions, sickle hemoglobin, a natural mutant of human hemoglobin A with a surface hydrophobic valine in place of a negatively charged glutamic acid, polymerizes at high volume occupancy. Equilibrium solubility of sickle hemoglobin entails activity coefficients that can approach 103 at high concentrations. Polymerization occurs by homogeneous and heterogeneous nucleation mechanisms, which are both profoundly sensitive to crowding; homogeneous nucleation rates for example are enhanced by 1010 when the initial concentration is augmented by 50% non‐polymerizing hemoglobin. A molecular description of the reaction therefore entails substantial corrections for molecular crowding which are all very accurately described by excluded volume corrections, treating hemoglobin as a hard sphere with volume consistent with the molecular structure of the molecule, and involving no further adjustable parameters. These effects and the descriptions that rationalize this behavior are described. Copyright © 2004 John Wiley & Sons, Ltd.
Crowding effects in binary mixtures of rod‐like and spherical particles
Authors: Lago S. , Cuetos A. , Martínez‐Haya B. , Rull L. F.
Published: August 2004

Crowding effects relevant to the phase stability of binary mixtures of rod‐like and spherical particles are investigated by means of Monte Carlo simulations in the isobaric NPT ensemble. The two types of particles are represented, respectively, by freely rotating hard spherocylinders of a moderate aspect ratio (L / σ = 5) and hard spheres of the same diameter σ. Molar fractions of spheres ranging xHS = 0.00–0.37 are considered with the aim of characterizing the crowding effects on the liquid crystal phases of the hard spherocylinder fluid induced by the spherical component as depleting agent. We find that the addition of the spherical crowder is beneficial for the stabilization of the layers of the rod‐like particles characteristic of the smectic phase. On the contrary, the addition of spheres has a negative impact upon the stability of the nematic phase, where the rod‐like particles tend to align collectively parallel to each other. Interestingly, the spheres tend to arrange forming rod‐like clusters in the nematic phase and lamellar structures in the smectic phase, which is compensated by the entropy gained by the spherocylinder particles in each phase. The main results are in qualitative agreement with recent experimental and theoretical studies and serve to test the prediction of current equations of state for these types of binary mixtures. Copyright © 2004 John Wiley & Sons, Ltd.
Non‐ideal tracer sedimentation equilibrium: a powerful tool for the characterization of macromolecular interactions in crowded solutions
Authors: Rivas Germán , Minton Allen P.
Published: August 2004

Non‐ideal tracer sedimentation equilibrium is a technique devised to quantify the effect of high concentrations of unrelated macromolecules on the self‐ or hetero‐associations of dilute macromolecules. Principles and experimental techniques are reviewed, and previous experimental work summarized. A new analysis of experimental data is presented that requires no a priori assumptions regarding the nature of weak repulsive interactions between solute species and the concentrated (crowding) species. Published in 2004 by John Wiley & Sons, Ltd.
Genomic channeling in bacterial cell division
Authors: Mingorance Jesús , Tamames Javier , Vicente Miguel
Published: August 2004

The bacterial dcw cluster is a group of genes involved in cell division and peptidoglycan synthesis. Comparison of the cluster across several bacterial genomes shows that its gene content and its gene order are conserved in distant bacterial lineages and, moreover, that, being most conserved in rod‐shaped bacteria, the degree of conservation relates to bacterial morphology. We propose a model in which the selective pressure to maintain the cluster arises from the need to efficiently coordinate the processes of elongation and septation in rod‐shaped bacteria. Gene order in the dcw cluster would be conserved as a result of mechanisms comprising: (i) a limited amout of peptidoglycan precursors required both for septation and elongation of the wall; (ii) co‐translational assembly of the protein complexes involved in cell division and in the synthesis of the peptidoglycan precursors; and (iii) alternation in the cellular localization of the assembled complexes to participate either in the synthesis of the septal peptidoglycan and division, or in the synthesis of the lateral wall. The name genomic channeling is proposed for this model as it involves a genomic arrangement that could facilitate the assembly of specific protein complexes and their subsequent conveyance to specific locations in the crowded cytoplasm and the envelope. Copyright © 2004 John Wiley & Sons, Ltd.
Changes produced in the aroma compounds and structural integrity of basil (Ocimum basilicum L) during drying
Authors: Díaz‐Maroto M Consuelo , Sánchez Palomo Eva , Castro Lucía , González Viñas MA , Pérez‐Coello M Soledad
Published: August 2004

The influence of drying on the aroma compounds, from a chemical and sensory standpoint, and on the structural integrity of basil (Ocimum basilicum L) was evaluated. The drying methods tested were oven drying at 45 °C, air drying at room temperature and freeze‐drying. The volatile compounds of fresh and dried basil were extracted and concentrated by simultaneous distillation/extraction and analysed by gas chromatography/mass spectrometry. In all, 27 volatile components were identified, linalool being the major component, followed by eugenol. The total quantity of volatiles of fresh basil decreased considerably during oven drying and freeze‐drying, whereas air drying of basil at room temperature brought about only small losses of volatile components. The cell damage produced on basil leaves during drying was evaluated by scanning electron microscopy. From a sensory standpoint, fresh basil was described as having a fresh, herbaceous and floral odour, while the dried samples had a mentholated, spicy, hay‐like and earthy odour. Copyright © 2004 Society of Chemical Industry
Reactions of CH3O2 radicals on solid surface
Authors: Manucharova L. A. , Tsarukyan S. V. , Vardanyan I. A.
Published: August 2004

The reaction probability of CH3O2 radicals with NO2, CH4, C3H6, and CH3CHO on the solid surface of KCl in flow at low pressure and temperature range of 297–353 K has been studied. The chosen conditions allowed excluding homogeneous interaction of radicals. The heterogeneous radical decay of peracetic acid served as a source of CH3O2 radicals.

On the basis of ESR measurements of CH3O2 radicals with the above‐mentioned compounds, a heterogeneous reaction mechanism has been identified.

The reactivity of NO2 was greatest for the compounds studied.

The effective activation energy was evaluated to be 10.4 ± 0.8 kJ/mol for the reaction of RO2 radicals with NO2 and −21.3 ± 2.8 kJ/mol for methane. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 591–595, 2004
Stopped‐flow investigation of the reaction of hexabromoiridate(III) with bromine in aqueous solution
Authors: Hoag Craig M. , Hanrahan Robert J.
Published: August 2004

The reaction of hexabromoiridate(III) with bromine to form hexabromoiridate(IV) and bromide ion was studied using a Durrum stopped‐flow spectrophotometer. Special precautions were taken while studying this reaction. All of the experiments were carried out within 3 min after preparation of the hexabromoiridate solution throughout this investigation in order to limit the amount of conversion of hexabromoiridate(III) to aquapentabromoiridate(III) before reaction with bromine. Very dilute solutions were used because of the rapidity of the reaction. The rate constant for the reaction at 24 ± 1°C was determined to be (3.2 ± 0.4) × 103 L mol−1 s−1. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 623–626, 2004