bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning of the koi herpesvirus (KHV) gene encoding thymidine kinase and its use for a highly sensitive PCR based diagnosis
Authors: Bercovier Herve , Fishman Yolanta , Nahary Ronen , Sinai Sharon , Zlotkin Amir , Eyngor Marina , Gilad Oren , Eldar Avi , Hedrick Ronald P
Published: March 2005

Background

Outbreaks with mass mortality among common carp Cyprinus carpio carpio and koi Cyprinus carpio koi have occurred worldwide since 1998. The herpes-like virus isolated from diseased fish is different from Herpesvirus cyprini and channel catfish virus and was accordingly designated koi herpesvirus (KHV). Diagnosis of KHV infection based on viral isolation and current PCR assays has a limited sensitivity and therefore new tools for the diagnosis of KHV infections are necessary.

Results

A robust and sensitive PCR assay based on a defined gene sequence of KHV was developed to improve the diagnosis of KHV infection. From a KHV genomic library, a hypothetical thymidine kinase gene (TK) was identified, subcloned and expressed as a recombinant protein. Preliminary characterization of the recombinant TK showed that it has a kinase activity using dTTP but not dCTP as a substrate. A PCR assay based on primers selected from the defined DNA sequence of the TK gene was developed and resulted in a 409 bp amplified fragment. The TK based PCR assay did not amplify the DNAs of other fish herpesviruses such as Herpesvirus cyprini (CHV) and the channel catfish virus (CCV). The TK based PCR assay was specific for the detection of KHV and was able to detect as little as 10 fentograms of KHV DNA corresponding to 30 virions. The TK based PCR was compared to previously described PCR assays and to viral culture in diseased fish and was shown to be the most sensitive method of diagnosis of KHV infection.

Conclusion

The TK based PCR assay developed in this work was shown to be specific for the detection of KHV. The TK based PCR assay was more sensitive for the detection of KHV than previously described PCR assays; it was as sensitive as virus isolation which is the golden standard method for KHV diagnosis and was able to detect as little as 10 fentograms of KHV DNA corresponding to 30 virions.
Emergence of unusual species of enterococci causing infections, South India
Authors: Prakash Vittal P , Rao Sambasiva R , Parija Subash C
Published: March 2005

Background

Enterococci tend to be one of the leading causes of nosocomial infections, with E. faecalis and E. faecium accounting up to 90% of the clinical isolates. Nevertheless, the incidence of other species of enterococci from clinical sources shows an alarming increase with the properties of intrinsic resistance to several antibiotics including beta-lactams and glycopeptides. Thus proper identification of enterococci to species level is quintessential for management and prevention of these bacteria in any healthcare facility. Hence this work was undertaken to study the prevalence of unusual species of enterococci causing human infections, in a tertiary care hospital in South India.

Methods

The study was conducted in a tertiary care hospital in South India from July 2001 to June 2003. Isolates of enterococci were collected from various clinical specimens and speciated using extensive phenotypic and physiological tests. Antimicrobial susceptibility testing were performed and interpreted as per NCCLS guidelines. Whole cell protein (WCP) fingerprinting of enterococci were done for species validation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and analyzed computationally.

Results

Our study showed the prevalence of unusual (non-faecalis and non-faecium enterococci) and atypical (biochemical variant) species of enterococci as 19% (46 isolates) and 5% (12 isolates) respectively. The 7 unusual species (46 isolates) isolated and confirmed by phenotypic characterization includes: 15 E. gallinarum (6.2%), 10 E. avium (4.1%), 6 E. raffinosus (2.5%), 6 E. hirae (2.5%), 4 E. mundtii (1.7%), 3 E. casseliflavus-including the two atypical isolates (1.2%) and 2 E. durans (0.8%). The 12 atypical enterococcal species (5%) that showed aberrant sugar reactions in conventional phenotyping were confirmed as E. faecalis, E. faecium and E. casseliflavus respectively by WCP fingerprinting. The antimicrobial susceptibility testing depicted the emergence of high-level aminoglycoside and beta-lactam resistance among different species apart from intrinsic vancomycin resistance by some species, while all the species tested were susceptible for linezolid and teicoplanin.

Conclusion

Our study reveals the emergence of multi-drug resistance among unusual species of enterococci posing a serious therapeutic challenge. Precise identification of enterococci to species level enables us to access the species-specific antimicrobial resistance characteristics, apart from knowing the epidemiological pattern and their clinical significance in human infections.
A review of HIV prevention among young injecting drug users: A guide for researchers
Authors: Dolan Kate A , Niven Heather
Published: March 2005

Young people aged 15–24 years account for fifty percent of all new AIDS cases worldwide. Moreover, half of all new HIV infections are associated with injection drug use. The average age for initiation into injecting drug use is 20 years of age. This paper investigates whether HIV prevention programs have reduced risk behaviours in young people.
Clinical Characteristics of Pheochromocytoma Patients With Germline Mutations in SDHD
Authors: Dannenberg Hilde , van Nederveen Francien H. , Abbou Mustaffa , Verhofstad Albert A. , Komminoth Paul , de Krijger Ronald R. , Dinjens Winand N.M.
Published: March 2005

Purpose

We examined the value of SDHD mutation screening in patients presenting with apparently sporadic and familial pheochromocytoma for the identification of SDHD-related pheochromocytomas.

Patients and Methods

This retrospective study involved 126 patients with adrenal or extra-adrenal pheochromocytomas, including 24 patients with a family history of multiple endocrine neoplasia 2, von Hippel-Lindau disease, neurofibromatosis type 1, or paraganglioma (PGL). Conformation-dependent gel electrophoresis and sequence determination analysis of germline and tumor DNA were used to identify SDHD alterations. The clinical and molecular characteristics of sporadic and hereditary tumors were compared. We reviewed the literature and compared our results with those from previously published studies.

Results

Pathogenic germline SDHD mutations were identified in three patients: two (2.0%) of the 102 apparently sporadic pheochromocytoma patients and one patient with a family history of PGL. These patients presented with multifocal disease (two of three multifocal patients) or with a single adrenal tumor (one of 82 patients). In the literature, mutations are mostly found in patients ≤ 35 years of age or presenting with multifocal or extra-adrenal disease. All patients with an SDHD mutation developed extra-adrenal tumors (pheochromocytomas or PGLs) at presentation or during follow-up.

Conclusion

SDHD gene mutations in patients presenting with apparently sporadic adrenal pheochromocytoma are rare. We recommend SDHD mutation screening for patients presenting with a family history of pheochromocytoma or PGL, multiple tumors, isolated adrenal or extra-adrenal pheochromocytomas, and age ≤ 35 years. Analysis of SDHD can also help to distinguish synchronous primary tumors from abdominal metastases.
Thermodynamic stability and transformation of pharmaceutical polymorphs
Authors: Kitamura Mitsutaka
Published: March 2005

The thermodynamic stability and transformation of pharmaceutical polymorphs was investigated, especially those of the thiazole derivative pharmaceutical, 2-(3-cyano-4-isobutyloxyphenyl)-4-methyl-5-thiazolecarboxylic acid (BPT). The influence of methanol compositions in solvents and temperature on the solubility and the transformation behavior of BPT was clarified. The transformation behavior was explained by the chemical potential difference between the stable and metastable forms. It was shown that a specific solute–solvent interaction contributes to the preferential nucleation and growth of the stable or metastable forms and influences the transformation behaviors. The solubility of BPT of the solvated crystals is much more influenced by the solvent compositions than the true polymorphs. The solubility ratio of the solvated crystals depends on the solvent composition, whereas the solubility ratio of the true polymorphs is considered to be independent of the solvents. The crystallization behavior was also investigated. The transformation rate after crystallization appeared to depend on the initial concentration of BPT and the addition rate of the antisolvent. The cause of this phenomenon was presumed to be a slight inclusion of the stable form in the metastable form.
Consistency issues of aqueous solubility data and solution thermodynamics of electrolytes
Authors: De Visscher Alex , Vanderdeelen Jan
Published: March 2005

For the calculation of aqueous solubility of electrolytes, thermodynamic data from different sources are required. This can lead to errors if the data are inconsistent. This study reveals that some often-used semi-empirical equations for CO2 solubility and other equilibria are inconsistent with CODATA (Committee on Data for Science and Technology) key thermodynamic data. The equations were recalculated to make them consistent with CODATA. Combining standard thermodynamic data of NaCl with the Pitzer model leads to significant deviations from the accepted experimental value at 25 °C. Owing to the inadequacy of the Pitzer model at molalities exceeding 6 mol kg–1, this model leads to poor predictions of the HCl vapor pressure in equilibrium with highly concentrated aqueous HCl solutions. A long-standing inconsistency problem is related to the solubility of calcium carbonate. The main problem is disagreement on the existence of the CaHCO3
+ ion pair. It is shown that the inconsistency largely disappears if it is assumed that the CaHCO3
+ exists at low ionic strength, but becomes less stable at higher ionic strength.
Temperature effects on trimethylamine oxide accumulation and the relationship between plasma concentration and tissue levels in smelt (Osmerus mordax)
Authors: Treberg Jason R. , Bystriansky Jason S. , Driedzic William R.
Published: March 2005

Rainbow smelt (Osmerus mordax) were maintained in a long term acclimation study to elucidate temperature effects on the accumulation of trimethylamine oxide (TMAO) and to determine if the activity of trimethylamine oxidase (TMAoxi) plays a role in modulating the seasonally variable levels of TMAO. In the same experiment, the TMAO content was determined for several tissues at varying plasma TMAO concentrations. TMAO accumulation begins at 5–7°C, well above that which might be normally associated with an antifreeze response. The plasma concentration reached a plateau of 20 mM as temperatures reached 0°C. Plasma TMAO concentration drops to pre‐accumulation levels, less than 5 mM, when fish are held at elevated temperature (8–11°C) and increases when fish are chilled below ambient seawater temperatures. However, despite temperatures near or below 0°C, plasma TMAO decreases after the winter season. Changes in TMAoxi activity do not correlate with TMAO levels, suggesting that the activity of this enzyme does not play a key role in regulating TMAO concentrations in smelt. For the first time in any teleost fish, tissue TMAO contents in liver, kidney, brain, and intestine were found to strongly correlate with plasma TMAO concentrations. For these tissues, the intracellular and extracellular concentration of TMAO appears to be approximately equal. Conversely, the heart and white muscle accumulate TMAO, and in the case of white muscle, intracellular concentration is maintained at a constant level of approximately 35 mmol/kg, despite fluctuating plasma concentrations over a range from 0 to over 25 mM. J. Exp. Zool. 303A:283–293, 2005. © 2005 Wiley‐Liss, Inc.
Reduction of pectinesterase activity in a commercial enzyme preparation by pulsed electric fields: comparison of inactivation kinetic models
Authors: Giner Joaquín , Grouberman Pascal , Gimeno Vicente , Martín Olga
Published: March 2005

The inactivation of pectinesterase (PE) in a commercial enzyme preparation (CEP) under high intensity pulsed electric fields (HIPEF) was studied. After desalting and water dilution of the raw CEP, samples were exposed to exponentially decay waveform pulses for up to 463 µs at electric field intensities ranging from 19 to 38 kV cm−1. Pulses were applied in monopolar mode. Experimental data were fitted to a first‐order kinetic model as well as to models based on Fermi, Hülsheger or Weibull equations to describe PE inactivation kinetics. Characteristic parameters for each model were calculated. Relationships between some of the parameters and process variables were obtained. The Weibull model yielded the best accuracy factor. The relationship between residual PE and input of electrical energy density was found to be that of exponential decay. Copyright © 2005 Society of Chemical Industry
Trends in cpue and related changes in spatial distribution of demersal fish species in the Kattegat and Skagerrak, eastern North Sea, between 1981 and 2003
Authors: Casini Michele , Cardinale Massimiliano , Hjelm Joakim , Vitale Francesca
Published: March 2005

We explored the trends in ln-transformed catch per unit effort, defined as average weight (kg) per 1 h trawling, and the spatial distribution of 32 demersal fish species in the Kattegat and Skagerrak using International Bottom Trawl Survey data collected between 1981 and 2003. As in other areas, the biomass of roundfish species such as cod, pollack, hake, and ling drastically decreased during this period most likely owing to fishing pressure. However, other commercially important fish species, e.g. haddock, whiting, and some flatfish, showed a constant or increasing trend during the same period. Non-commercial species showed no or an increasing trend in ln-cpue, by as much as 40 times in hagfish. Furthermore, analyses of the spatial distribution of 14 selected fish species by means of distribution maps of ln-cpue suggested that fish stocks contracted and expanded in response to decrease and increase of the stock biomass, respectively, with some flatfish species (i.e. plaice and flounder) and hagfish representing the exceptions to this general pattern.
The Man Who Changed China: The Life and Legacy of Jiang Zemin. By ROBERT LAWRENCE KUHN. [New York: Crown Publishers, 2005. 688 pp.+two 16-page photo inserts. $35.00. ISBN 1-4000-5474-5.]
Authors: Gilley Bruce
Published: March 2005

Robert Kuhn's lengthy biography of Jiang Zemin sets out to tell the inside story of this unlikely leader of China from 1989 to 2004. An American investment banker and television producer with business interests in China, Kuhn was given access to many of Jiang's closest friends, aides and political allies. Yet the long-anticipated result is short of expectations. Much of the book is a dry rehashing of Jiang's official schedule from year to year, with Trollopian chapter subtitles like “How could I not know?” The occasional glimpses into the inner political and personal world of the man are so fleeting as to leave the reader more frustrated than gratified.

To be sure, the careful reader will turn up a host of interesting facts here that enhance our understanding of Jiang: for example, he began his life as an anti-drugs protestor not aware that the protests he joined were organized by the CCP. There is also a vivid James Bond-like scene of Jiang speeding a friend to safety in Shanghai at the wheel of an American jeep in 1948. And there are glimpses of real world politics. Jiang's chief mentor, Wang Daohan, commented candidly to Jiang in 1989 on the “many complications and contradictions” of politics in Beijing “especially all the subtle conflicts between different interest groups.” His sister notes of his elevation to Party chief: “We certainly didn't celebrate. His appointment wasn't worth celebrating.” Later, Jiang's wife, Wang Yeping, is quoted as saying she was always dismayed by the files on her husband's desk that suggested a daily crisis of governance. “Explosions here, rioting there. Murders, corruption, terrorism – little that was nice.” Unfortunately, these factional conflicts and governance crises are nowhere to be found in the narrative, which offers instead a steady diet of Jiang's meetings with foreign leaders and “important” speeches.
The Chinese Journalist. By HUGO DE BURGH. [London, RoutledgeCurzon, 2003. 248pp. £65.00. ISBN 0-415-30573-X.]
Authors: Gittings John
Published: March 2005

One can obtain as wide a range of views on the state of health of the Chinese media as on any other subject these days. Chinese journalists who remember the press up to 25 years ago will assert how much greater freedom exists now. Even the reporting of traffic accidents was forbidden, as Hugo de Burgh points out, “until the taboo was broken around 1980” (p. 36). (In Shanghai, I was told, it was broken when the Jiefang ribao reported that a trolley bus had caught fire on Huaihai Road.)

Younger journalists are more likely to chafe at the limits still imposed upon the media. Many seek to pursue media studies abroad, explaining that they hope to be better qualified if or when there is a new breakthrough in China. Others continue to push at the limits, sometimes getting sacked but often able to move on to another media outlet in another province. Those working for web-based media are often bolder than their print counterparts – including journalists on the People's Daily website who exposed the notorious Nandan tin mine disaster in 2001.

This is a timely book which, as its title suggests, focuses on the Chinese journalist rather than on Chinese journalism – a distinction that would have been impossible to draw until recent years. It is based on fieldwork as well as wide reading although the value of some interview material is reduced by the necessity – revealing in itself – to mask the interviewees' identity.
Monitoring rapid temporal change in a volcano with coda wave interferometry
Authors: Grêt Alexander , Snieder Roel , Aster Richard C. , Kyle Philip R.
Published: March 2005

Multiply–scattered waves typically dominate the late part of the seismic coda in local earthquake seismograms. Small medium changes that have no detectable influence on the first arrivals are amplified by multiple scattering and may thus be readily observed in the coda. We exploit this idea using Coda Wave Interferometry to monitor temporal changes at Mount Erebus Volcano, Antarctica. Erebus is one of the few volcanoes on Earth with a long–lived convecting lava lake. Large exsolved gas bubbles generate impulsive Strombolian explosions that provide a repeating seismic source of seismic energy propagating through the strongly scattering geology of the volcano. We examined these signals during a particularly active eruptive two–month period between December, 1999 and February, 2000. Early seismograms are highly reproducible throughout this period. During the first month this is also the case for the coda. Approximately midway through this period, however, the seismic coda decorrelates rapidly over a period of several days. This indicates a rapid change in the scattering properties of the volcano, likely reflecting subtle changes in the near–summit magma/conduit system that would not be discernible using direct– or single–scattered seismic wave methods.
Global structure of the out‐of‐ecliptic solar wind
Authors: Whang Y. C. , Wang Y.‐M. , Sheeley N. R. , Burlaga L. F.
Published: March 2005

We use the observed photospheric field maps and the wind speed observed from Ulysses to study the out‐of‐ecliptic solar wind. The model calculates the wind speed from the rate of magnetic flux tube expansion factors using a conversion function that is determined by least squares fit of all currently available data from Ulysses. Using the best fit conversion function, we investigate the global solar wind covering a 36‐year period from 1968 through 2003. The results complement and expand upon earlier studies conducted with interplanetary scintillation and other in situ spacecraft observations. The rotationally averaged wind speed is a function of two parameters: the heliolatitude and the phase of the solar cycle. The out‐of‐ecliptic solar wind has a recurrent stable structure, and the average wind speed varies like a sine square of latitude profile spanning more than 5 years during the declining phase and solar minimum in each solar cycle. Ulysses has observed this stable structure in its first polar orbit in 1992–1997. Near solar maximum the structure of the out‐of‐ecliptic solar wind is in a transient state lasting 2–3 years when the stable structure breaks down during the disappearance and reappearance of the polar coronal holes.
Theoretical characterization of dihydrogen adducts with alkaline cations
Authors: Vitillo Jenny G. , Damin Alessandro , Zecchina Adriano , Ricchiardi Gabriele
Published: March 2005

As part of an extended fundamental study on the interaction of molecular hydrogen with the surfaces of potential storage materials, this work describes the interaction of dihydrogen with bare alkaline cations (Li+,Na+,K+,Rb+) by means of ab initio and density functional calculations. The effects of method and basis set are evaluated, and an estimate of the electrostatic contributions to the binding energy is evaluated. All methods predict a t-shaped coordination geometry, in accord with the quadrupolar nature of the molecule. The binding energies at the MP2/aug-cc-pVQZ (MP2—Møller–Plesset method truncated at second order) level ranges between 24kJ∕mol for Li+ and 5kJ∕mol for Rb+. Basis set size has minor effect on the binding energy of the complexes, although the poorer sets have severe limitations in the description of the electrostatics of the isolated molecule. The electrostatic contribution to the binding energy calculated from the electrostatic properties of the isolated molecule are in fact strongly basis set dependent. Their careful analysis shows that the predominant terms of the interaction are those due to the quadrupole and dipole-polarizability terms. The vibrational spectra of the adducts are evaluated and compared with a large set of experimental and theoretical results from the literature. This review highlights a linear correlation between the frequency shift and the binding energy, which is valuable in the understanding of adsorption phenomena by means of spectroscopic methods.
Experimental setup for simultaneous measurements of neutron diffraction and dielectric spectroscopy during crystallization of liquids
Authors: Jiménez-Ruiz M. , Sanz A. , Nogales A. , Ezquerra T. A.
Published: March 2005

Here we present an experimental setup to obtain information on structural and dynamical changes in liquids during crystallization. This setup consists in a sample cell that allows performing simultaneous measurements of neutron diffraction and dielectric spectroscopy experiments. The capabilities of the technique have been probed by following in real time the crystallization process of a model liquid: the isopropanol. By performing the simultaneous experiment information can be obtained from both phases, amorphous and crystalline, and therefore it can provide a complete description of the changes occurring during a crystallization process. The use of this setup allowed us to demonstrate that a breakage of the hydrogen-bond network is a precursor step for the crystallization of isopropanol.
Tripartite loss model for Mach-Zehnder interferometers with application to phase sensitivity
Authors: Parks A. D. , Spence S. E. , Troupe J. E. , Rodecap N. J.
Published: March 2005

An analytical loss model for Mach-Zehnder interferometers (MZIs) is developed and used to provide a general phase sensitivity expression for arbitrary photon input states. The model takes into account phase regime, regional losses, and regional internal “environmental” conditions and is therefore useful for understanding the relationships among these factors and phase sensitivity. The ground state MZI is also defined and the associated model’s formalism is used to deduce several well established MZI phase sensitivity performance characteristics. It is shown that this ground state model represents nonideal MZIs for a wide range of operational frequencies and environmental conditions. This model also predicts that Heisenberg limited phase sensitivity cannot be achieved by a lossy MZI. Rather, for large input photon number and instrument efficiency η, the limiting phase sensitivity is the associated shot-noise limit scaled by the factor 21−η.
Photoluminescence intermittency in an individual single-walled carbon nanotube at room temperature
Authors: Matsuda K. , Kanemitsu Y. , Irie K. , Saiki T. , Someya T. , Miyauchi S. , Maruyama S.
Published: March 2005

We described the photoluminescence (PL) properties of individual micelle-encapsulated single-walled carbon nanotubes (SWNTs) at room temperature. Single PL peak from isolated individual SWNT with a chiral index of (6, 5) showed a linear increase and saturation behavior of the PL intensity. Unusual PL intensity fluctuation in the temporal evolutions of the PL intensity, referred to as PL intermittency, was seen with some SWNTs, while the PL intensity with most SWNTs remained at a constant amplitude. The mechanism of the PL intermittency was discussed.
Superconductivity near 35 K in aligned amorphous magnesium-doped BMgx nanowires
Authors: Cao Limin , Zhang Ze , Wen Haihu , Wang Wenkui
Published: March 2005

We report the superconductivity near 35 K in magnesium-doped boron nanowires, BMgx(x≈0.1), which were synthesized via the reaction of well-aligned amorphous boron nanowires with magnesium vapor in vacuum-sealed quartz tubes. Electron microscopy and electron energy-loss spectroscopy reveal that the BMgx nanowires have an amorphous structure with magnesium content of ∼10at.%, far less than that in crystalline MgB2, and magnesium distributes uniformly in the nanowires. Our results provide a base material not only for low-temperature nanodevice applications but also for theoretical investigations on the mechanism of its superconductivity.
Histone methyltransferases G9a and GLP form heteromeric complexes and are both crucial for methylation of euchromatin at H3-K9
Authors: Tachibana Makoto , Ueda Jun , Fukuda Mikiko , Takeda Naoki , Ohta Tsutomu , Iwanari Hiroko , Sakihama Toshiko , Kodama Tatsuhiko , Hamakubo Takao , Shinkai Yoichi
Published: March 2005

Histone H3 Lys 9 (H3-K9) methylation is a crucial epigenetic mark for transcriptional silencing. G9a is the major mammalian H3-K9 methyltransferase that targets euchromatic regions and is essential for murine embryogenesis. There is a single G9a-related methyltransferase in mammals, called GLP/Eu-HMTase1. Here we show that GLP is also important for H3-K9 methylation of mouse euchromatin. GLP-deficiency led to embryonic lethality, a severe reduction of H3-K9 mono- and dimethylation, the induction of Mage-a gene expression, and HP1 relocalization in embryonic stem cells, all of which were phenotypes of G9a-deficiency. Furthermore, we show that G9a and GLP formed a stoichiometric heteromeric complex in a wide variety of cell types. Biochemical analyses revealed that formation of the G9a/GLP complex was dependent on their enzymatic SET domains. Taken together, our new findings revealed that G9a and GLP cooperatively exert H3-K9 methyltransferase function in vivo, likely through the formation of higher-order heteromeric complexes.
The effects of shrimps on benthic material in a Brazilian island stream
Authors: DE SOUZA MARCELO L. , MOULTON TIMOTHY P.
Published: March 2005

1. Shrimps are abundant in many tropical coastal streams. Studies in Central America and the Caribbean have demonstrated the importance of shrimps in removing sediments and altering the composition of the benthos. Previous work in our study area showed that ephemeropterans and not shrimps were important in removing benthic material.

2. Here we used an experimental exclusion to test the hypothesis that shrimps exert strong influence on sediment dynamics with direct and indirect effects on the benthic algal and faunal community at a site where they are the predominant element of macrofauna. We used electricity to exclude Macrobrachium olfersi and Potimirim glabra from small quadrats (0.135 m2) for 34 days in a stream located at Ilha Grande, Rio de Janeiro state, Brazil. We analysed benthic sediment dynamics and community colonisation during this period on artificial substrates in electrified and not‐electrified quadrats.

3. Significantly higher sediment accrual had occurred in the electrified treatment after 14 days and persisted for the 34‐day course of the experiment; substrates protected from shrimps contained about four times as much ash‐free dry mass (AFDM) as those of the controls. After 34 days, significantly more pennate diatoms were present in the exclusion treatment, but chlorophyll was not significantly different between treatments. Densities of baetid ephemeropteran nymphs were significantly higher in the presence of shrimps.

4. We attribute all these effects to the atyid P. glabra, the more abundant and active shrimp observed in the control treatment. Our results suggest that atyid shrimps played an important role related to sediment removal on hard substrate by direct ingestion and ‘bioturbation’. They reduced certain components of the periphyton (pennate diatoms) without affecting primary production (chlorophyll a). The activity of these shrimps on periphyton affected also faunal components such as baetid ephemeropterans and seems to determine the composition of the benthic community.
Modelling habitat associations with fingernail clam (Family: Sphaeriidae) counts at multiple spatial scales using hierarchical count models
Authors: GRAY BRIAN R. , HARO ROGER J. , ROGALA JAMES T. , SAUER JENNIFER S.
Published: March 2005

1. Macroinvertebrate count data often exhibit nested or hierarchical structure. Examples include multiple measurements along each of a set of streams, and multiple synoptic measurements from each of a set of ponds. With data exhibiting hierarchical structure, outcomes at both sampling (e.g. within stream) and aggregated (e.g. stream) scales are often of interest. Unfortunately, methods for modelling hierarchical count data have received little attention in the ecological literature.

2. We demonstrate the use of hierarchical count models using fingernail clam (Family: Sphaeriidae) count data and habitat predictors derived from sampling and aggregated spatial scales. The sampling scale corresponded to that of a standard Ponar grab (0.052 m2) and the aggregated scale to impounded and backwater regions within 38–197 km reaches of the Upper Mississippi River. Impounded and backwater regions were resampled annually for 10 years. Consequently, measurements on clams were nested within years. Counts were treated as negative binomial random variates, and means from each resampling event as random departures from the impounded and backwater region grand means.

3. Clam models were improved by the addition of covariates that varied at both the sampling and regional scales. Substrate composition varied at the sampling scale and was associated with model improvements, and reductions (for a given mean) in variance at the sampling scale. Inorganic suspended solids (ISS) levels, measured in the summer preceding sampling, also yielded model improvements and were associated with reductions in variances at the regional rather than sampling scales. ISS levels were negatively associated with mean clam counts.

4. Hierarchical models allow hierarchically structured data to be modelled without ignoring information specific to levels of the hierarchy. In addition, information at each hierarchical level may be modelled as functions of covariates that themselves vary by and within levels. As a result, hierarchical models provide researchers and resource managers with a method for modelling hierarchical data that explicitly recognises both the sampling design and the information contained in the corresponding data.
A 24‐year follow‐up of root filled teeth and periapical health amongst middle aged and elderly women in Göteborg, Sweden
Authors: Frisk F. , Hakeberg M.
Published: March 2005

Aim  To describe the endodontic status amongst middle‐aged and elderly women longitudinally and cross‐sectionally over 24 years.

Methodology  A random sample of 1462 women 38, 46, 50, 54 and 60 years old, living in Göteborg, Sweden, were sampled in 1968 for medical and dental examinations with a participation rate of 90.1%. The same women were re‐examined in 1980 and 1992 together with new 38‐ and 50‐year‐old women. The dental examination consisted of questionnaires, clinical and panoramic radiological survey (OPG). The number of teeth, number of root filled teeth (RF) and number of teeth with periapical radiolucencies (PA) were registered. The RF and PA ratios were calculated. Cross‐sectional data were analysed by means of anova and longitudinal data by a general linear model for repeated measures. Sample prevalences were compared and statistical inferences were made with the chi‐squared test. In all analysis, the confidence interval (CI) regarded mean difference between groups (95% CI).

Results  The RF and PA ratio decreased over time as well as the frequency of edentulous subjects. Cross‐sectional analysis revealed a minor increase in frequency of RF and PA and loss of teeth with age. Longitudinally, loss of teeth was evident in all cohorts. In addition, there was a trend of lower number of teeth with PA, and the RF ratio increased with age.

Conclusions  The prevalence of periapical disease did not increase with age, probably as a result of root canal treatment and extractions. Data showed that the prevalence of RF teeth and teeth with PA decreased for comparable age cohorts during the 24‐year follow‐up.
Medicine taking decisions: schizophrenia in comparison to asthma and epilepsy
Authors: MARLAND G. R. , CASH K.
Published: March 2005

This paper outlines a recent PhD study that explored factors underpinning decisions of people with schizophrenia regarding neuroleptic medicine taking. Relevant studies tend to be within the world view of psychiatry, resting on traditional concepts of compliance and insight. These studies examined schizophrenia outwith the context of other illnesses taking a snap shot view of medicine taking decision making, thus de‐emphasizing its process. The chosen method of grounded theory (Glaser and Strauss 1967) overcomes these deficiencies. Stage 1 data arose from patient interviews, patients with asthma, epilepsy and schizophrenia contributed (n = 45), carers also sometimes contributed (n = 11), all three conditions being episodic disorders vulnerable to environmental stressors. Stage 2 develops from stage 1, mental health workers involved in the care of people with schizophrenia were interviewed, plus one asthma specialist and one epilepsy specialist (n = 16). Their views were compared to perspectives arising from the patient interviews and were included in the data, out of which an explanatory typology emerged. The three parts of the typology comprise the study's major categories and are labelled as: direct‐reactive, deferential‐compliant, and active discerning and optimizing. Active discerning and optimizing consists of two stages; experimental‐reflective and consolidation. The core category of responsive resolution contains themes which run through all major categories.
Substance use and young people: the potential of technology
Authors: CHAMBERS M. , CONNOR S. L. , MCELHINNEY S.
Published: March 2005

There is widespread concern about alcohol and drug use and abuse among young people in the United Kingdom, Europe and the United States. Evaluations of current drug and alcohol education approaches have mixed findings and some methodological difficulties. This paper reports on exploratory research to explore the potential of technology to provide information and support to young people regarding substance use and abuse. Eight focus groups were conducted with young people (n = 78) and three with key informants (n = 22). The findings revealed that technology has potential to provide information on this topic, and that young people are critical of some of the more traditional methods of provision. The young people were prepared to experiment with technology, felt competent to do so, and made suggestions of information they would like. These findings are discussed and recommendations made for future research in the area.
Characteristics and staff resources of child and adolescent psychiatric hospital wards in Finland
Authors: ELLILÄ H. , SOURANDER A. , VÄLIMÄKI M. , PIHA J.
Published: March 2005

The aim of this study is to describe structural characteristics and staff resources of child psychiatric and adolescent psychiatric hospital wards in Finland. The target group of the survey consisted of 69 child and adolescent psychiatric hospital units in Finland. Information was obtained from 64 units (93%). Most of the wards were based on 24‐h‐a‐day provision. There were only 7‐day‐treatment programmes including two family wards. When compared internationally, the numbers of units, beds and staff levels were high in Finland, with all members of staff qualified. The nurse–patient ratio and psychiatrist resources were rather satisfactory. However, in many units there was a lack of psychologists, social workers and occupational therapists. General recommendations and guidelines for staff resources in child and adolescent hospital treatment wards are warranted.
Training in cognitive behavioural interventions on acute psychiatric inpatient wards
Authors: McCANN E. , BOWERS L.
Published: March 2005

There has been a drive towards addressing the types of care and therapeutic interventions available to people with serious mental illness, which is reflected in the latest government mental health policy initiatives. Recent evidence strongly supports the implementation of psychological and social interventions for people with psychosis, and in particular the use of cognitive behavioural techniques. Until now, the main focus has been on people living in the community. This study examines the delivery of psychosocial interventions training to qualified psychiatric nurses and unqualified staff on seven acute psychiatric admission wards in London, UK. The approach had the strength of on‐site delivery, follow‐up role modelling of the interventions and clinical supervision. Despite this, in some cases the training was less successful, mainly because of staffing and leadership weaknesses. The impact of training in these methods and the implications for mental health education and practice development are discussed.
In vitro function of platelet concentrates prepared after filtration of whole blood or buffy coat pools
Authors: Turner C. P. , Sutherland J. , Wadhwa M. , Dilger P. , Cardigan R.
Published: March 2005

Background/method  Data on the quality of platelet concentrates (PC) produced by the buffy coat method and stored beyond 5 days in plasma are limited. We therefore evaluated the quality of PCs prepared by leucocyte depletion of whole blood (Terumo WBSP, n = 10) or a buffy coat pool (Pall Autostop, n = 10), and stored for 7 days in plasma by assessing platelet parameters and markers of platelet activation.

Results  In both types of PC, levels of glucose decreased during storage but were not totally depleted (> 11 mM on day 7). In contrast, lactate levels increased on storage and was consistently < 20 mM throughout, with pH maintained at > 6·8 in all units. Hypotonic shock response scores were > 47% in all units at day 7. On day 1, markers of platelet activation were significantly higher in WBSP PC, but by day 7 were similar for percentage CD63+ and CD62P + (40%) with levels of platelet microparticles and annexin V binding two‐fold higher in WBSP. The expression of CD61 did not alter during storage and the percentage of platelets expressing CD42b was > 88% in all units on day 7. RANTES (Regulated on activation, normal, T‐cell expressed and secreted) and TGFβ released from platelets by day 7 was < 800 ng/ml and 90 ng/ml, respectively. C3adesarg increased throughout storage in both types of PC, but without a commensurate increase in the terminal complex SC5b‐9 or activation of factor XII.

Conclusion  Our data indicates that the in vitro characteristics of PCs prepared using these methods is maintained over storage for 7 days in plasma and is not associated with significant deterioration of platelet function.

One sentence summary  In vitro function of platelet concentrates prepared by either filtration of whole blood, or pooled buffy coats
The Effects of Group Incentives in an Indian Firm: Evidence from Payroll Data
Authors: Bhattacherjee Debashish
Published: March 2005

Abstract.  This paper estimates the effects of group incentives on productivity, pay and employment in a large unionized firm in India. Using plant‐level monthly time‐series data from the payroll office for the period 1985–95, and controlling for both (plant) fixed effects and (contract) time effects, the paper provides econometric evidence on the effectiveness of both the level and intensity of incentive pay on the outcome measures. In addition, the relative performance of two types of group incentives defined on the basis of group size is also analysed. The results generally confirm predictions from theory that productivity returns to incentives are non‐linear and concave in shape and that the effectiveness of incentives is decreasing in group size. It is argued that the latter is most likely due to the lessening of the free‐rider problem and the increased effectiveness of peer monitoring associated with smaller groups. The results also point to a negative relationship between the level of incentives and employment over time.
Management of early viable cervical pregnancy
Authors: Mesogitis Spiros , Pilalis Athanasios , Daskalakis George , Papantoniou Nikolaos , Antsaklis Aris
Published: March 2005

Objective  To evaluate conservative management of early viable cervical pregnancy.

Design  Prospective study.

Setting  A tertiary teaching hospital.

Population  All cases of cervical pregnancies with fetal cardiac activity presenting to our hospital over six years.

Methods  All cases were managed with trans‐abdominal intra‐amniotic injection of 25 mg of methotrexate under ultrasound guidance. Follow up sonographic examinations and serum β‐hCG measurements were performed every three days. Cervical curettage was performed after two follow up ultrasound examinations had shown a dead fetus and a regressing gestational sac as well as declining β‐hCG levels. Patients were managed as outpatients.

Main outcome measures  Successful management and need for hospitalisation.

Results  Nine cases were encountered. Two required a second injection of methotrexate for persistent fetal cardiac activity and serum β‐hCG rise in the follow up examination. We did not observe any side effects and no patient required admission to the hospital.

Conclusions  Intra‐amniotic methotrexate injection and subsequent cervical curettage after one week is a successful alternative for the management of cervical pregnancies.
AMP kinase activation with AICAR further increases fatty acid oxidation and blunts triacylglycerol hydrolysis in contracting rat soleus muscle
Authors: Smith Angela C. , Bruce Clinton R. , Dyck David J.
Published: March 2005

Muscle contraction increases glucose uptake and fatty acid (FA) metabolism in isolated rat skeletal muscle, due at least in part to an increase in AMP‐activated kinase activity (AMPK). However, the extent to which AMPK plays a role in the regulation of substrate utilization during contraction is not fully understood. We examined the acute effects of 5‐aminoimidazole‐4‐carboxamide riboside (AICAR; 2 mm), a pharmacological activator of AMPK, on FA metabolism and glucose oxidation during high intensity tetanic contraction in isolated rat soleus muscle strips. Muscle strips were exposed to two different FA concentrations (low fatty acid, LFA, 0.2 mm; high fatty acid, HFA, 1 mm) to examine the role that FA availability may play in both exogenous and endogenous FA metabolism with contraction and AICAR. Synergistic increases in AMPK α2 activity (+45%; P < 0.05) were observed after 30 min of contraction with AICAR, which further increased exogenous FA oxidation (LFA: +71%, P < 0.05; HFA: +46%, P < 0.05) regardless of FA availability. While there were no changes in triacylglycerol (TAG) esterification, AICAR did increase the ratio of FA partitioned to oxidation relative to TAG esterification (LFA: +65%, P < 0.05). AICAR significantly blunted endogenous TAG hydrolysis (LFA: −294%, P < 0.001; HFA: −117%, P < 0.05), but had no effect on endogenous oxidation rates, suggesting a better matching between TAG hydrolysis and subsequent oxidative needs of the muscle. There was no effect of AICAR on the already elevated rates of glucose oxidation during contraction. These results suggest that FA metabolism is very sensitive to AMPK α2 stimulation during contraction.
Ontogeny and nutritional programming of uncoupling protein‐2 and glucocorticoid receptor mRNA in the ovine lung
Authors: Gnanalingham M. G. , Mostyn A. , Dandrea J. , Yakubu D. P. , Symonds M. E. , Stephenson T.
Published: March 2005

This study investigated the developmental and nutritional programming of uncoupling protein‐2 (UCP2), glucocorticoid receptor (GR) and 11β‐hydroxysteroid dehydrogenase type 1 (11βHSD1) mRNA in the sheep lung from the time of uterine attachment to 6 months of age. The effect of maternal nutrient restriction on lung development was determined in early to mid gestation (i.e. 28–80 days gestation, period of maximal placental growth, and embryonic and pseudoglandular stages of fetal lung development) and late gestation (i.e. 110–147 days gestation, period of maximal fetal growth, and canalicular and saccular stages of fetal lung development). Fetal lungs were sampled at 80 and 140 days (term ∼148 days) gestation, and sheep lungs at 1, 7, 30 days and 6 months. GR and 11βHSD1 mRNA were maximal at 140 days gestation, whereas UCP2 mRNA peaked at 1 day of age and then declined with postnatal age. Maternal nutrient restriction in both early‐to‐mid and late gestation had no effect on lung weight, but increased UCP2, GR and 11βHSD1 mRNA abundance at every sampling age. These findings suggest that the developmental ontogeny of UCP2 mRNA in the ovine lung is under local glucocorticoid hormone action and that maternal nutrient restriction has long‐term consequences for UCP2 and GR mRNA abundance in the lung irrespective of its timing.
THE REFLEX-FREE HULL
Authors: AHN HEE-KAP , CHENG SIU-WING , CHEONG OTFRIED , SNOEYINK JACK
Published: March 2005

We propose a hull operator, the reflex-free hull, that allows us to define a 3D analogue to bays in polygons. The reflex-free hull allows a rich set of topological types, yet for polyhedral input with n edges, it remains a polyhedral set with O(n) edges. This is in contrast to other possible hull definitions that give non-planar surfaces and higher combinatorial complexity. The reflex-free hull is related to identifying cavities in computer aided design and manufacturing, but we sketch examples to indicate that computing a reflex-free hull will be a challenging problem.
COMPUTATIONAL GEOMETRY COLUMN 46
Authors: O'ROURKE JOSEPH
Published: March 2005

The old problem of determining the chromatic number of the plane is revisited.