bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitivity of photodissociation rate coefficients and O3 photochemical tendencies to aerosols and clouds
Authors: Yang Huiyan , Levy Hiram
Published: December 2004

We examine the sensitivity of the daily integrated photodissociation rate (DIPR) coefficients of O3(O1D) and NO2, the daily averaged O3 photochemical tendency, and OH concentration to variations of clouds and of four aerosol components: black carbon (BC), mineral dust, sea salt, and sulfate. Clouds and BC aerosols are found to be the most important. A comparison between the sensitivity study and some representative observations showed that the global average cloud reduction of DIPR at the surface level is ∼20% and it is ∼30% in storm track zones. At the surface level the average negative BC impact is ∼10% in urban areas and could reach ∼40% in some heavily polluted urban areas. Mineral dust aerosol, which is the next most important, can reduce the photochemistry at the surface level by over 17% in some seasons over the desert or along its long‐range transport paths. The negative impact of sulfate aerosols is around 2% at the surface level, and the impact is as positive as 4% at the top of the sulfate aerosol layer in some urban areas. BC, sulfate, and mineral dust all have much smaller impacts away from their source regions. The impact of sea‐salt aerosol is generally less than 1%. While the fractional impacts on O3 production and destruction and OH concentration do not depend much on NOx, the magnitude of the impact on O3 chemical tendency and OH concentration depends strongly on the concentration of NOx: When NOx is very low, the impacts are also very small even if DIPRs are strongly affected. Different mixing states of absorbing and scattering aerosol components, external, coating, and internal, are studied. It is found that with the same amount of each component, the external mixing state produces the weakest impact while the internal mixing state produces the strongest impact. Coating has almost the same impact as internal mixing. There is very little synergy between cloud and absorbing aerosols when clouds are located above the aerosol. The aerosol absorption is strengthened when clouds and aerosol are located in the same layer. The synergy is strong when clouds are located below the absorbing aerosol, where the impact of absorbing aerosol dominates.
Design of instrumentation for probing changes in electrospray droplets via the Stern–Volmer relationship
Authors: Ham Jason E. , Durham Bill , Scott Jill R.
Published: December 2004

Electrospray ionization (ESI) is a proven method for introducing large intact molecules into the gas phase. However, the processes that occur within this ion source are poorly understood. We have developed instrumentation and methodology to probe the evolution of droplets within the electrospray plume. Using emission lifetime spectroscopy, excited-state lifetimes of [Ru(bpy)3]2+ with and without a known quencher, 2,3,5,6-tetramethyl-p-phenlyenediamine, present were observed. Lifetimes were shown to decrease as quencher concentration increased, as expected. Rate constants (with and without quencher present) were determined and correlated with quencher concentration using the Stern–Volmer relationship. Stern–Volmer plots reveal the linearity of the quenching reaction and can be used to determine the concentrations of species within the electrosprayed droplets. The evolution of the ESI droplets can be probed by comparing the concentration of a species at different locations within the plume.
Measurement of residual stress in multicrystalline silicon ribbons by a self-calibrating infrared photoelastic method
Authors: Brito M. C. , Pereira J. P. , Maia Alves J. , Serra J. M. , Vallera A. M.
Published: December 2004

This article reports on a method for the measurement of residual stress in multicrystalline silicon ribbons, based on the infrared photoelastic technique. This self-calibrating method allows the in situ determination of the photoelastic coefficients and can thus be used for any crystal orientation. The method was validated by the experimental determination of the photoelastic coefficient of monocrystalline (100) silicon wafers and by comparison with strain measurements using asymmetrical x-ray diffraction. The distribution of residual stress in multicrystalline silicon ribbons was also measured. The results showed strong evidence for tensile stress in the central region and compressive stress near the edges of the ribbons. Both the measured residual stress and the photoelastic coefficient distributions are correlated to grain boundaries.
Envelope solitons associated with electromagnetic waves in a magnetized pair plasma
Authors: Cattaert Tom , Kourakis Ioannis , Shukla P. K.
Published: December 2004

The amplitude modulation of magnetic field-aligned circularly polarized electromagnetic (CPEM) waves in a magnetized pair plasma is reexamined. The nonlinear frequency shifts include the effects of the radiation pressure driven density and compressional magnetic field perturbations as well as relativistic particle mass variations. The dynamics of the modulated CPEM wave packets is governed by a nonlinear Schrödinger equation, which has attractive and repulsive interaction potentials for fast and slow CPEM waves. The modulational stability of a constant amplitude CPEM wave is studied by deriving a nonlinear dispersion from the cubic Schrödinger equation. The fast (slow) CPEM mode is modulationally unstable (stable). Possible stationary amplitude solutions of the modulated fast (slow) CPEM mode can be represented in the form of bright and dark/gray envelope electromagnetic soliton structures. Localized envelope excitations can be associated with the microstructures in pulsar magnetospheres and in laboratory pair magnetoplasmas.
A systematic revision of the New Zealand longicorn beetle genus Drototelus Broun (Coleoptera : Cerambycidae : Cerambycinae)
Authors: Wang Qiao , Lu Wen
Published: December 2004

The New Zealand endemic longicorn beetle genus Drototelus Broun is revised. The scope of the genus is redefined. The monotypic genus Neocalliprason Brookes is synonymised with Drototelus. Two known species, D. politus Broun and D. elegans (Brookes), are redescribed and one new species, D. rarus, is described. These changes have brought the number of Drototelus species to three. Distribution and biology are noted for each species. Adults are diurnally active flower-visitors, and larvae are dead-wood feeders. Phylogenetic relationships of these species are cladistically analysed, confirming the monophyly of the revised genus and determining the sister-species relationship between D. politus and D. rarus.
Turbulence increases the average settling velocity of phytoplankton cells
Authors: Ruiz Javier , Macías Diego , Peters Francesc
Published: December 2004

It is a well known fact that stirring keeps particles suspended in fluids. This is apparent, for instance, when shaking medicine flasks, when agitating tea deposits in a mug, or when heavy winds fill the air with dust particles. The commonplace nature of such observations makes it easy to accept that this feature will apply to any natural phenomenon as long as the flow is turbulent enough. This has been the case for phytoplankton in the surface mixed layers of lakes and oceans. The traditional view assumes that an increase in turbulence bears ecological advantages for nonmotile groups like diatoms that, otherwise, would settle in deep and unlit waters. However, this assumption has no theoretical ground, and the experimental results we present here point in the opposite direction. Phytoplankton settling velocity increases when turbulence intensifies from the low to the higher values recorded in the upper mixed layers of lakes and oceans. Consequently, turbulence does not favor phytoplankton remaining in lit waters but is rather an environmental stress that can only be avoided through morphological and/or physiological adaptations.
Responses of fibroblasts to anchorage of dorsal extracellular matrix receptors
Authors: Beningo Karen A. , Dembo Micah , Wang Yu-li
Published: December 2004

Fibroblasts in 2D cultures differ dramatically in behavior from those in the 3D environment of a multicellular organism. However, the basis of this disparity is unknown. A key difference is the spatial arrangement of anchored extracellular matrix (ECM) receptors to the ventral surface in 2D cultures and throughout the entire surface in 3D cultures. Therefore, we asked whether changing the topography of ECM receptor anchorage alone could invoke a morphological response. By using polyacrylamide-based substrates to present anchored fibronectin or collagen on dorsal cell surfaces, we found that well spread fibroblasts in 2D cultures quickly changed into a bipolar or stellate morphology similar to fibroblasts
in vivo
. Cells in this environment lacked lamellipodia and large actin bundles and formed small focal adhesions only near focused sites of protrusion. These responses depend on substrate rigidity, calcium ion, and, likely, the calcium-dependent protease calpain. We suggest that fibroblasts respond to both spatial distribution and mechanical input of anchored ECM receptors. Changes in cell shape may in turn affect diverse cellular activities, including gene expression, growth, and differentiation, as shown in numerous previous studies.
Measurement of a linear free energy relationship one molecule at a time
Authors: Rao B. V. , Kwon K.-Y. , Liu A. , Bartels L.
Published: December 2004

A systematic study of the dehydrogenation of substituted thiophenols by controlled charge injection from the tip of a scanning tunneling microscope (STM) reveals a pronounced dependence of the reaction yield on the position and the chemical nature of the substituent. We evaluate the dehydrogenation rate of
para
-halo-substituted species within a linear free energy relationship, namely the Hammett equation. The resultant ρ value of 1.4 can faithfully predict the reaction rates of molecules that are
meta
-halo-substituted or
para
-methyl-substituted. The positive sign of ρ suggests a negatively charged transition state at the core of the STM-induced process, and the magnitude of the ρ value indicates that the presence of the substrate does not preclude substantial substituent effects. The applicability of the Hammett equation to single-molecule chemistry offers facile prediction of the rate of STM-based single-molecule chemistry in a field, which so far has been addressed by focusing on involved quantum-mechanical modeling of its underlying processes.
Regulation of inducible nitric oxide synthase by rapid cellular turnover and cotranslational down-regulation by dimerization inhibitors
Authors: Kolodziejski Pawel J. , Koo Ja-Seok , Eissa N. Tony
Published: December 2004

Overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of many disorders. iNOS is notably distinguished from constitutive NOSs by its production of large amounts of NO for a prolonged period; hence, it was termed the high-output NOS. Understanding how cells regulate iNOS is a prerequisite for strategies aimed at modulating NO synthesis. iNOS is thought to be regulated primarily at the transcriptional level in response to cytokines and inflammatory mediators. In this study, we report a posttranslational regulatory mechanism for control of iNOS expression through a rapid cellular rate of turnover. Unexpectedly, iNOS cellular half-life was found to be relatively short. In primary bronchial epithelial cells, iNOS half-life was 1.6 ± 0.3 h. A similar half-life was found for iNOS in several cell lines. This fast rate of turnover is in sharp contrast to that reported for the constitutive NOS isoforms. iNOS half-life was not affected by intracellular depletion of tetrahydrobiopterin, a critical cofactor required for iNOS activity. Further, iNOS monomers and dimers had a similar half-life. Importantly, we discovered a previously unrecognized cotranslational down-regulation mechanism by which the newly discovered pyrimidineimidazole-based allosteric dimerization inhibitors of iNOS lead to reduced iNOS expression. This study provides insights into the cellular posttranslational mechanisms of iNOS and has important implications for design of selective iNOS inhibitors and their use in therapeutic strategies.
Human myoglobin recognition of oxygen: Dynamics of the energy landscape
Authors: Wang Yuhong , Baskin J. Spencer , Xia Tianbing , Zewail Ahmed H.
Published: December 2004

Femtosecond to nanosecond dynamics of O
2
rebinding to human WT myoglobin and its mutants, V68F and I107F, have been studied by using transient absorption. The results are compared with NO rebinding. Even though the immediate environment around the heme binding site is changed by the mutations, the picosecond geminate rebinding of oxygen is at most minimally affected. On the other hand, the V68F (E11) mutation causes drastic differences in rebinding on the nanosecond time scale, whereas the effect of the I107F (G8) mutation remains relatively small within our 10-ns time window. Unlike traditional homogeneous kinetics and molecular dynamics collisional simulations, we propose a “bifurcation model” for populations of directed and undirected dynamics on the ultrafast time scale, reflecting the distribution of initial protein conformations. The major mutation effect occurs on the time scale on which global protein conformational change is possible, consistent with transitions between the conformations of directed and undirected population playing a role in the O
2
binding. We discuss the relevance of these findings to the bimolecular function of the protein.
MRI and Muscle Signal Intensities in Alcoholics Compared With Control Subjects
Authors: Bigliocchi Marco , Lo Mele Luigi , Stasolla Alessandro , Kharrub Zaher , Riley Edward P. , Ceccanti Mauro , Attilia Maria L. , Giacomelli Stefano , Masciangelo Raffaele , Marini Mario
Published: December 2004

Objective: To evaluate by magnetic resonance imaging (MRI) the difference in muscle signal intensities between alcoholics and control subjects.

Methods: Thirty‐four healthy subjects and 46 alcohol‐dependent individuals were assessed. MRI was carried out using a low‐field magnet (0.2 Tesla) and a limb‐dedicated coil. The presence of muscle changes was evaluated by measuring signal intensities at the medial (MG) and lateral heads of the gastrocnemius muscle by T1‐/T2‐weighted and gradient‐echo short tau inversion recovery sequences. The mean signal intensities of the two sample groups were compared by ANCOVA with age as a covariate. In the alcohol‐dependent group, correlations between signal intensities and plasma levels of muscular and hepatic enzymes, in addition to years of high‐risk consumption and lifetime dose of ethanol consumed, were assessed. The mean signal intensities were also compared with the different degrees of pain by ANOVA.

Results: Compared with healthy subjects, the alcohol‐dependent group had mean higher signal intensities in both gastrocnemius heads in all sequences. The difference in the MG in T2‐weighted sequences was significant (F= 48.28, p < 0.01). A modest correlation between the years of high‐risk consumption and the signal intensity was found in T2‐weighted sequences in the MG (r= 0.288, p= 0.057), whereas a correlation with the lifetime dose consumed was not found. Significant correlations between signal intensities and plasma levels of muscular and hepatic enzymes were not found. There were also no significant group differences on different degrees of pain.

Conclusion: MRI was shown to be a sensitive, well‐tolerated, and inexpensive procedure capable of detecting changes in signal intensities in the muscles of alcoholics. This technique could be included among other diagnostic tools for alcoholic myopathy with further improvements and if the signal alterations can be corroborated by biopsy evidence.
Brain Catalase Activity Inhibition as Well as Opioid Receptor Antagonism Increases Ethanol‐Induced HPA Axis Activation
Authors: Pastor Raúl , Sanchis‐Segura Carles , Aragon Carlos M.G.
Published: December 2004

Background: Growing evidence indicates that brain catalase activity is involved in the psychopharmacological actions of ethanol. Recent data suggest that participation of this enzymatic system in some ethanol effects could be mediated by the endogenous opioid system. The present study assessed whether brain catalase has a role in ethanol‐induced activation of the HPA axis, a neuroendocrine system modulated by the endogenous opioid neurotransmission.

Methods: Swiss male mice received an intraperitoneal injection of the catalase inhibitor 3‐amino‐1,2,4‐triazole (AT; 0–1 g/kg), and 0 to 20 hr after this administration, animals received an ethanol (0–4 g/kg; intraperitoneally) challenge. Thirty, 60, or 120 min after ethanol administration, plasma corticosterone levels were determined immunoenzymatically. In addition, we tested the effects of 45 mg/kg of cyanamide (another catalase inhibitor) and 0 to 2 mg/kg of naltrexone (nonselective opioid receptor antagonist) on ethanol‐induced enhancement in plasma corticosterone values.

Results: The present study revealed that AT boosts ethanol‐induced increase in plasma corticosterone levels in a dose‐ and time‐dependent manner. However, it did not affect corticosterone values when measured after administration of saline, cocaine (4 mg/kg, intraperitoneally), or morphine (30 mg/kg, intraperitoneally). The catalase inhibitor cyanamide (45 mg/kg, intraperitoneally) also increased ethanol‐related plasma corticosterone levels. These effects of AT and cyanamide on ethanol‐induced corticosterone values were observed under treatment conditions that decreased significantly brain catalase activity. Indeed, a significant correlation between effects of catalase manipulations on both variables was found. Finally, we found that the administration of naltrexone enhanced the levels of plasma corticosterone after the administration of saline or ethanol.

Conclusions: This study shows that the inhibition of brain catalase increases ethanol‐induced plasma corticosterone levels. Results are discussed together with previous findings suggesting a putative linkage between brain ethanol metabolism and the endogenous opioid system to explain some of the neuroendocrine effects of ethanol.
Mismatch Negativity: No Difference Between Treatment‐Naive Alcoholics and Controls
Authors: Fein George , McGillivray Shannon , Finn Peter
Published: December 2004

Background: Several studies have examined the mismatch negativity (MMN) evoked potential as a measure of a brain inhibitory deficit in alcoholics or those at risk for alcoholism. This study examined MMN in actively drinking treatment‐naive alcohol‐dependent individuals. This study examined the association of MMN with risk factors for alcoholism, postalcohol withdrawal hyperexcitability, and alcohol use variables.

Methods: Electroencephalograms were gathered on 84 subjects (42 controls and 42 treatment‐naive alcohol‐dependent individuals) during a nonattending MMN experiment. Alcoholism family history density, the number of externalizing disorder symptoms, and psychological indices of deviance proneness served as measures of risk factors associated with the vulnerability to alcoholism. Alcohol use variables were used as measures of alcoholism severity.

Results: There were no differences in the MMN integral, amplitude, or latency between control and treatment‐naive alcohol‐dependent subjects. There also were no significant associations of MMN measures with any of the measures of alcoholism vulnerability, with any of the alcohol use variables, or with the prevalence or severity of symptoms of postalcohol withdrawal hyperexcitability.

Conclusions: Although there is a strong association between alcohol abuse and symptoms of disinhibition and deviance proneness, the MMN response does not offer any direct physiological evidence of this phenomenon.
Microarray Analysis of Ethanol‐Treated Cortical Neurons Reveals Disruption of Genes Related to the Ubiquitin‐Proteasome Pathway and Protein Synthesis
Authors: Gutala Ramana , Wang Ju , Kadapakkam Sheila , Hwang Yoon , Ticku Maharaj , Li Ming D.
Published: December 2004

Background: Chronic ethanol abuse results in deleterious behavioral responses such as tolerance, dependence, reinforcement, sensitization, and craving. The objective of this research was to identify transcripts that are differentially regulated in ethanol‐treated cortical neurons compared with controls by using a pathway‐focused complementary DNA microarray.

Methods: Cortical neurons were isolated from postconception day 14 C57BL/6 mouse fetuses and cultured according to a standard protocol. The cortical neuronal cells were treated with 100 mM ethanol for five consecutive days with a change of media every day. A homeostatic pathway‐focused microarray consisting of 638 sequence‐verified genes was used to measure transcripts differentially regulated in four ethanol‐treated cortical neuron samples and four control samples. Quantitative real‐time reverse transcriptase‐polymerase chain reaction analysis was used to verify the mRNA expression levels of genes of interest detected from the microarray experiments.

Results: We identified 56 down‐regulated and 10 up‐regulated genes in ethanol‐treated cortical neurons relative to untreated controls at a 5% false‐discovery rate. The expression of many genes involved in ubiquitin‐proteasome and protein synthesis was decreased by ethanol, including ubiquitin B, ubiquitin‐like 3, ubiquitin‐conjugating enzyme E3A, 20S proteasome α‐ and β‐subunits, and members of the ribosomal proteins. Furthermore, the mRNA expression of heat shock proteins, myristoylated alanine‐rich protein kinase C substrate, phosphatase and tensin homolog deleted on chromosome 10, and FK506 binding protein rapamycin‐associated protein (FKBP) (mTOR) was also decreased in ethanol‐treated cortical neurons. Quantitative real‐time reverse transcriptase‐polymerase chain reaction analysis of genes involved in the ubiquitin‐proteasome cascade revealed a down‐regulation of these genes, thereby corroborating our microarray results.

Conclusions: Our results indicate that chronic ethanol treatment of cortical neurons resulted in decreased mRNA expression of genes involving the ubiquitin‐proteasome pathway and ribosomal proteins together with mTOR expression leading to disruption of protein degradation mechanism and impairment of protein synthesis machinery.
Large cutaneous rabbit papillomas that persist during cyclosporin A treatment can regress spontaneously after cessation of immunosuppression
Authors: Hu Jiafen , Peng Xuwen , Cladel Nancy M. , Pickel Martin D. , Christensen Neil D.
Published: December 2004

Cottontail rabbit papillomavirus (CRPV)-induced papillomas can progress into malignant carcinomas, remain persistent or regress. Both host immunity and virus genetic background play critical roles in these events. To test how host immunity influences CRPV-induced papilloma evolution, both EIII/JC (inbred) and New Zealand White (outbred) rabbits were treated with an immunosuppressive drug, cyclosporin A (CsA), for 80 days and the regression of three regressive constructs, H.CRPVr (a CRPV regressive strain), H.CRPVp-E6r (a progressive strain with regressive E6) and H.CRPVp-CE6rm (H.CRPVp with the carboxyl terminal of regressive E6, containing mutations at amino acid residues E252G, G258D and S259P) was checked. Papillomas induced by H.CRPVr and H.CRPVp-E6r on control inbred and outbred rabbits regressed totally around week 8, whereas papillomas on all CsA-treated rabbits grew progressively. After cessation of CsA treatment, papillomas began to regress in six outbred rabbits: 14 of 18 papillomas induced by CRPVr, 11 of 18 papillomas induced by H.CRPVp-E6r and eight of 10 papillomas induced by H.CRPVp-CE6rm regressed around week 21. In four CsA-treated inbred rabbits, two of 17 papillomas induced by H.CRPVr and one of 17 papillomas induced by H.CRPVp-E6r regressed. These data indicate that papillomas induced by a regressive CRPV strain can become persistent in the transiently immunosuppressed host. However, returning immunity can lead to regression and clearance of large papillomas (with increased antigenicity) in an outbred population, whilst these same antigenic papillomas persist in inbred rabbits.
Severe acute respiratory syndrome coronavirus nucleocapsid protein expressed by an adenovirus vector is phosphorylated and immunogenic in mice
Authors: Zakhartchouk Alexander N. , Viswanathan Sathiyanarayanan , Mahony James B. , Gauldie Jack , Babiuk Lorne A.
Published: December 2004

Severe acute respiratory syndrome coronavirus (SARS-CoV) has been identified as the aetiological agent of SARS. Thus, vaccination against SARS-CoV may represent an effective approach towards controlling SARS. The nucleocapsid (N) protein is thought to play a role in induction of cell-mediated immunity to SARS-CoV and thus it is important to characterize this protein. In the present study, an E1/partially E3-deleted, replication-defective human adenovirus 5 (Ad5) vector (Ad5-N-V) expressing the SARS-CoV N protein was constructed. The N protein, expressed in vitro by Ad5-N-V, was of the expected molecular mass of 50 kDa and was phosphorylated. Vaccination of C57BL/6 mice with Ad5-N-V generated potent SARS-CoV-specific humoral and T cell-mediated immune responses. These results show that Ad5-N-V may potentially be used as a SARS-CoV vaccine.
Ultrasonic evidence of placental calcification at 36 weeks' gestation: maternal and fetal outcomes
Authors: McKenna Daniel , Tharmaratnam Suresh , Mahsud Samina , Dornan James
Published: December 2004

Background.  To determine the significance of an inappropriately mature placenta on ultrasound examination (Grannum classification), in a low‐risk obstetric population. Scans were performed at 36 weeks' gestation. The study group comprised patients demonstrating a grade III placenta, and the control group comprised patients not demonstrating a grade III placenta.

Methods.  A total of 1802 low‐risk patients were scanned using serial directed real‐time ultrasound at 36 weeks' gestation to determine placental maturity.

Results.  The incidence of a grade III placenta at 36 weeks' gestation was 3.8% (68/1802). A grade III placenta was associated with young maternal age and cigarette smoking, p < 0.01. The incidence of proteinuric pregnancy‐induced hypertension in the study and control groups was 7.4% (5/68) and 1.56% (27/1734), respectively, p < 0.01. The proportion of infants with a weight less than the 10th centile at birth in the study and control groups was 17.6% (12/68) and 5.6% (97/1734), respectively, p < 0.01.

Conclusions.  Ultrasound detection of a grade III placenta at 36 weeks' gestation in a low‐risk population helps to identify the “at‐risk” pregnancy. It helps to predict subsequent development of proteinuric pregnancy‐induced hypertension and may help in identifying the growth‐restricted baby.
Growth hormone increases growth and dominance of wild juvenile Atlantic salmon without affecting space use
Authors: Martin‐Smith K. M. , Armstrong J. D. , Johnsson J. I. , Björnsson B. Th.
Published: December 2004

Growth hormone (GH) was applied to Atlantic salmonSalmo salarparr (the pre‐migratory freshwater life stage) to manipulate growth potential experimentally and to elucidate the effects on dominance status, actual growth, exploratory activity and home range. Experiments were conducted using seven groups of eight parr from May to September of two successive years. The fish were tagged with passive integrated transponders (PIT tags), tested for dominance, and then held in an enclosed section of a natural stream which was fitted with an array of PIT tag detectors to record space use at a definition ofc. 2 m. Relationships between dominance rank, space use and growth were established over 2 weeks. The four lowest ranking fish in each group were then given a slow‐release GH implant while the other fish received a placebo. The GH stimulated increase in fork length (LF) and mass and decrease in condition factor due to the relatively greater increase inLF. There was, however, an interaction between GH‐stimulated increase in growth and season, with the hormone having an effect only during the early part of the summer. Regardless of treatment, fish that moved most around their home range grew fastest. Increased growth in GH‐treated fish was associated with an increase in growth per unit movement, not increased total movement. This suggested that GH‐treated fish increased their rate of short‐distance (<2 m) foraging movements. Overall, space use, measured in terms of home range size and time allocation throughout the range, did not vary consistently in response to application of GH. There was a strong correlation between the weighted centre of the home range (a measure of position within the enclosure) before and after treatment, irrespective of whether fish were given GH or a placebo. The study shows that when density is low relative to carrying capacity, GH stimulates increased dominance and growth in a near‐natural environment without having measurable effects on space use at a definition ofc. 2 m. The results are interpreted as suggesting that high dominance status gives no significant growth advantage in a highly competitive situation, but increases foraging rate when food is abundant. Increased foraging appears to result from local changes in time budgeting rather than variations in the extent of home range and larger‐scale movements within it. Thus, in areas with declining wild Atlantic salmon populations where the habitat is unsaturated and food is abundant, introduced domestic Atlantic salmon may be competitively superior.
Genetic architecture of growth and early life‐history transitions in anadromous and derived freshwater populations of steelhead
Authors: Thrower F. P. , Hard J. J. , Joyce J. E.
Published: December 2004

Heritabilities of growth, precocious maturation and smolting were measured in 75 families of juvenile steelhead or rainbow troutOncorhynchus mykiss, progeny of within and between line matings (crosses) of wild, anadromous steelhead and wild, resident (lake) rainbow trout originally derived from the same anadromous stock 70 years earlier. The tagged yearling progeny were combined by line in common freshwater rearing containers and graded into three categories: mature, smolt or rearing (undifferentiated) at age 2 years. Heritabilities of precocious male maturity, smolting and growth were moderate to high, and the genetic correlation between growth and smolting was low. Smolting and precocious male maturity were highly variable among families within lines and significantly different between lines. Each of the four lines produced significant numbers of smolts at age two. Smolting and maturation were negatively genetically correlated, which may explain the persistence of smolting in the lake population despite strong selection against lake smolts; balancing selection on male maturation age may help to maintain variation for smolting. The high heritability of smolting, coupled with the inability of smolts that leave the lake to return to it indicates that the genetic potential for smolting can lie dormant or be maintained through a dynamic interaction between smolting and early maturation for decades despite complete selection against the phenotype. The results have significant implications for the preservation of threatened anadromous stocks in fresh water and the inclusion of resident fish of formerly anadromous populations, currently trapped behind long‐standing barriers to migration, as one component of the same population.
Photoperiod and temperature effects on gametogenesis in winter flounder Pseudopleuronectes americanus
Authors: Duchemin M. B. , Audet C. , Lambert Y.
Published: December 2004

The winter flounder is an in‐shore flatfish living in shallow waters on the east coast of North America from Labrador to Georgia. In the St Lawrence estuary, the reproductive season is May and June. Our objective was to test the effects of winter‐spring photoperiod and temperature conditions on the timing of sexual maturation in both males and females. Groups (16 animals each) of winter flounder breeders were maintained from mid‐January to mid‐May under five different experimental conditions: (1) natural photoperiod and temperature conditions; (2) natural photoperiod, 6° C; (3) 15L : 9D, natural temperature conditions; (4) 15L : 9D, 6° C; (5) accelerated photoperiod increase from winter to spring conditions, 6° C. Natural photoperiod and temperature conditions correspond to a gradual increase in light period from 8L : 16D (January) to 15L : 9D (May) and in temperature from −1° C (January to April) to 6° C (May). GSI and condition factor did not differ among the treatments (P > 0·05). In males, milt production occurred simultaneously in the different treatments and histological examination did not indicate any significant effect of either photoperiod or temperature on testes development. In females, seven stages of oocyte development were observed. Both the number of oocytes at the cortical alveoli stage and number of atretic oocytes increased at 6° C (warm temperature conditions). Overall, neither photoperiod nor temperature modified the reproductive period. Warm winter‐spring temperature conditions, however, may decrease egg numbers and egg quality.
About the oldest domesticates among fishes
Authors: Balon E. K.
Published: December 2004

Domestication of mammals such as cattle, dogs, pigs and horses preceded that of fishes by at least 10 000 years. The first domesticated fish was the common carpCyprinus carpio. Initially it was held as an exploited captive and did not undergo major changes in body shape or colour variations. About 2000 years ago, wild common carp were most abundant in the inland delta of the Danube River. These fish were torpedo shaped, golden‐yellow in colour and had two pairs of barbels and a mesh‐like scale pattern. Large schools of them thrived and reproduced on the flood plains of the Danube. The Romans kept fishes in specially built ponds at that time. The common carp was an ideal candidate and its rearing became more popular in medieval times. Common carp culture gradually became the most profitable branch of agriculture in central Europe and many special ponds were built. Soon common carp were being produced in pond systems including spawning and growing ponds. Unintentional artificial selection had taken place between the 12th and mid‐14th century, and deep bodied and variously scaled or scaleless domesticated forms appeared in nearly every pond system. Some colour aberrations appeared in the 1950s in Japan, which, as koi, became the most expensive of fish. Common carp were not originally domesticated in China but wild ‘chi’Carassius auratusoccasionally appeared as a xanthic form that, as the goldfish, has been known since 960 A.D. By the 1200s the fish were used as ornamental animals in the garden pools of rich landowners. Circa 1276 to 1546, the Chinese began keeping golden chi in aquarium‐like vessels and soon rich and poor alike became breeders of the fancy domesticated goldfish. The variously shaped monstrosities and colour aberrants were freaks but they became very fashionable at that time and still are. Domesticated goldfish monstrosities were first exported from China to Japan and much later to Europe and around the world. More recently other species have been domesticated by aquarists, such as the guppyPoecilia reticulataor the neon tetraParacheirodon innesi. Other fishes kept as ornamentals, like swordtailsXiphophorus helleriiand platiesXiphophorus maculatus, the discus and angelfishes (Cichlidae), as well as those cultured for food like the rainbow troutOncorhynchus mykiss, channel catfishIctalurus punctatusor sturgeons (Acipenseridae) are merely exploited captives.
Why do some fish do it younger than others? learning from experiments
Authors: Suquet M. , Rochet M.‐J. , Gaignon J. L.
Published: December 2004

Reproductive traits of fish such as age at first maturation or fecundity are not fixed: there is growing evidence that they change through time under the influence of various environmental factors, including fishing. Because these parameters are important in determining population dynamics, a better understanding of these changes is important to fisheries stock assessment. However, field studies are often inconclusive with respect to the ultimate causes of a given change. Although numerous experimental studies have been assessed the influence of environmental factors such as temperature on the reproduction in fish, these generally focus on single factors and do not consider the effects of the origin and individual history of experimental fish. There is scope for the development of ecological experiments to investigate the effects of interacting environmental factors on reproduction at the individual and population levels. This presentation will review experiments that could be used to predict environmental influences in the wild and the limits to such extrapolations. Finally, we will present a set of experiments designed to study maturation reaction norms in fish, i.e. the size at first reproduction as a function of age. We will investigate the effects of genotypes and environmental effects (feeding and temperature) on growth, age at maturity and subsequent spawning performances in reared cohorts.
The calpastatin/calpain system in trout Salmo trutta trutta muscle
Authors: Varricchio E. , Rubino T. , Paino S. , Di Lascio T. , Paciello O. , Langella M.
Published: December 2004

Many recent reports suggest that the calpastatin/calpain system plays a role in cellular growth and differentiation. Defects of the calpastatin/calpain system have been linked to cellular dysfunctions, apoptosis, myocardial infarct, and dystrophies. The calpastatin/calpain system has also been implicated in post‐mortem tenderization of skeletal muscle through degradation of key myofibrillar and associated proteins, a process of key importance to meat quality. In the present study we investigate the presence and activity of the calpastatin/calpain system in trout muscle samples, collected at 0, 3, 18 and 28 h post‐mortem, by immunohistochemistry method. Calpastatin is a specific endogenous enzyme of cytosol, modulating the ubiquitous calpains. Calpastatin was found in samples obtained in vivo and immediately post‐mortem, but its concentration declined rapidly in samples obtained 3, 18 and 28 h post‐mortem. The ubiquitous m e m‐calpains, which are localized on Z line proteins and activated by intracellular Ca2+ increase, showed a rapid decline within 3 h post‐mortem. By contrast p94 calpain, which is specific to skeletal muscle, showed a slow decrease post‐mortem which was independent of intracellular Ca2+ increase. Our results suggest that the mechanism of activation and activity of the calpastatin/calpain system in trout is similar to that described in mammals.
Arms and the Man: World War I and the Rise of the Welfare State
Authors: Dudley Leonard , Witt Ulrich
Published: December 2004

Why did peacetime government shares of total spending double in a number of Western economies between 1910 and 1938? The widely separated dates for the introduction of universal manhood suffrage and the evidence of a rise in protection during the inter‐war period indicate that neither democracy nor globalization can explain this development. This paper reexamines two other explanations, namely, (1) a shift in the demand for public goods and (2) a war‐induced willingness to share with one's fellow citizens. By introducing into Schelling's (1978) Multi‐Person Dilemma a learning game whose payoffs change endogenously, we provide theoretical explanations for this transformation. We then test the resulting propositions with data on public spending as a share of GNP for the U.S., Canada, the U.K., Germany and Denmark, from the 1870s to the 1930s. In each case, we find no unit root but a break in trend, a result shown to favor explanation (2) over (1).
The Political Economy of Privatization: Empirical Evidence from Transition Economies
Authors: Opper Sonja
Published: December 2004

This paper provides systematic evidence for both the cross‐country and sector‐independent validation of political‐economic theories used to explain changes in national property rights arrangements. A political‐economic model for privatization will be developed and then tested on progress in large‐scale and small‐scale privatizations in 14 Central and Eastern European transition economies between 1994 and 2000. It will be proven that divergent levels of progress in large‐scale privatization can be explained to a large extent by the structural and financial constraints on political decision‐makers and varying national interest group constellations. Small‐scale privatization is not significantly determined by political constraints and interest group pressure. This finding supports the assumption that the relative merits of different theories to explain changes in property rights arrangements depend crucially on the specific conditions of initial property arrangements.
Responsive Evaluation: the Meaning and Special Contribution to Public Administration
Authors: Abma Tineke
Published: December 2004

Responsive evaluation offers an emerging vision and rationale for evaluation. In the version of responsive evaluation presented here, evaluation is reframed from the assessment of policy interventions on the basis of policy‐makers’ questions to a dialogue among diverse stakeholder interests that moves towards reciprocal understanding and acceptance. This approach to evaluation is especially appropriate for the field of public administration, given the existing problems of complexity and the potential synergy with interactive and participatory policy approaches. Responsive evaluation and interactive approaches to public policy issues share the same democratic goals of participation and influence, and the alignment between these concepts make both sets of ideas and activities more effective and meaningful. The value and meaning of responsive evaluation and the synergy of this evaluation approach with the concept of public dialogue about important public issues is illustrated by a case study. This concerns a responsive evaluation of an organized policy dialogue about the future of the Dutch aviation infrastructure, known publicly as the Schiphol discussion.
Gendered Discourse about Family Business
Authors: Danes Sharon M. , Haberman Heather R. , McTavish Donald
Published: December 2004

Abstract: Language patterns of family business owners were explored by identifying discourse styles and emphasized ideas in four presenting contexts: business, family, intersection of family and business, and business success. The content analysis supports the existence of a general discourse style within family businesses and of similarities and differences between men and women in emphasized ideas as they frame their family businesses. The emotional discourse style (words of personal involvement, concern, and preference) was prominent across contexts for both genders, and there was a distinct absence of analytical language. Women had a higher emotional discourse style score for managing the business than did men, and balanced their emotional language with the practicality of planning tasks and creating efficiencies.
Neuroscience, education and special education
Authors: Goswami Usha
Published: December 2004

The discipline of neuroscience draws from the fields of neurology, psychology, physiology and biology, but is best understood in the wider world as ‘brain science’. Of particular interest for education is the development of techniques for ‘imaging’ the brain as it performs different cognitive functions. Cognitive neuroimaging has already led to advances in understanding some of the basic functions involved in learning and raised implications for education and special education in particular. For example, neuroimaging has enabled scientists to study the very complex processes underpinning speech and language, thinking and reasoning, reading and mathematics. In this article, Professor Usha Goswami of the University of Cambridge Faculty of Education first reviews basic information on brain development. She provides a brief introduction to the tools used in neuroimaging then considers recent findings from neuroscience that seem relevant to educational questions. Professor Goswami uses this review to suggest particular ways in which neuroscience research could inform special education. In its closing sections, this article provides authoritative perspectives on some of the ‘neuromyths’ that seem to have taken root in the popular imagination and argues for increased dialogue, in the future, between the disciplines of neuroscience and education.
Fostering communication and shared play between mainstream peers and children with autism: approaches, outcomes and experiences
Authors: Whitaker Philip
Published: December 2004

More pupils with autism are now being educated in mainstream settings and inevitably there is increased interest in their interactions with their peers. In this article, Philip Whitaker, of the Educational Psychology Service in Northamptonshire, describes his study of shared play between children with autism and their mainstream peers. The study involved ten youngsters with severe autism, educated in a unit attached to a mainstream school, and a group of volunteer ‘peer tutors’. The children met in weekly interaction sessions designed to promote shared play and communication. The peer tutors were provided with some coaching in interaction techniques and the impact of the intervention was evaluated through analysis of video recordings of play sessions made at the beginning and end of the project. The peer tutors and their parents were also interviewed at the end of the project to explore their experiences.

The results Philip Whitaker reports are encouraging. All parents were strongly supportive of their children's participation. All but one of the peer tutors found the experience challenging but rewarding and wanted to continue their involvement beyond the 20‐week project. The video evidence revealed that the peer tutors, with relatively limited preparation, were able to engage the youngsters with autism in high and sustained levels of shared play. The frequency of requesting by children with autism increased substantially over the course of the project, although levels of initiation of shared attention remained consistently low. Philip Whitaker concludes his report with a series of suggestions for enhancing the impact of this interesting work.