bluuebunny/crossref_metadata_2025 huggingface dataset:
Absence of force suppression in rabbit bladder correlates with low expression of heat shock protein 20
Authors: Batts Timothy W , Walker John S , Murphy Richard A , Rembold Christopher M
Published: November 2005

Background

Nitroglycerin can induce relaxation of swine carotid artery without sustained reductions in [Ca2+]i or myosin regulatory light chain (MRLC) phosphorylation. This has been termed force suppression and been found to correlate with ser16-phosphorylation of heat shock protein 20 (HSP20). We tested for the existence of this mechanism in a smooth muscle that is not responsive to nitric oxide.

Methods

Isometrically mounted mucosa free rabbit bladder strips were contracted with carbachol and relaxed with 8-Br-cGMP, forskolin, or isoprenaline.

Results

Contraction was associated with a highly cooperative relation between MRLC phosphorylation and force such that very small increases in MRLC phosphorylation induced large increases in force. Relaxation induced by 8-Br-cGMP, forskolin, or isoprenaline did not shift the MRLC phosphorylation-force relation from that observed with carbachol alone, i.e. there was no force suppression. HSP20 content was negligible (approximately two hundred-fold less than swine carotid).

Conclusion

The lack of force suppression in the absence of HSP20 is consistent with the hypothesized role for HSP20 in the force suppression observed in tonic smooth muscles.
Stakeholder views regarding cultural diversity teaching outcomes: a qualitative study
Authors: Dogra Nisha , Carter-Pokras Olivia
Published: November 2005

Background

Cultural diversity teaching is increasingly present in both undergraduate and postgraduate training programmes. This study explored the views of stakeholders in medical education about the potential outcomes of cultural diversity teaching and how they thought cultural diversity programmes might be effectively evaluated.

Methods

A semi-structured interview was undertaken with 61 stakeholders (including policymakers, diversity teachers, students and users). The data were analysed and themes identified.

Results

Many participants felt that clinical practice was improved through 'cultural diversity teaching' and this was mostly as a result of improved doctor-patient communication. There was a strong view that service users need to participate in the evaluation of outcomes of cultural diversity teaching.

Conclusion

There is a general perception, rather than clear evidence, that cultural diversity teaching can have a positive effect on clinical practice. Cultural diversity teaching needs to be reviewed in undergraduate and postgraduate medicine and better evaluation tools need to be established.
Immunohistochemical evidence for an endocrine/paracrine role for ghrelin in the reproductive tissues of sheep
Authors: Miller David W , Harrison Joanne L , Brown Yvonne A , Doyle Una , Lindsay Alanna , Adam Clare L , Lea Richard G
Published: November 2005

Background

The gut hormone, ghrelin, is involved in the neuroendocrine and metabolic responses to hunger. In monogastric species, circulating ghrelin levels show clear meal-related and body weight-related changes. The pattern of secretion and its role in ruminant species is less clear. Ghrelin acts via growth hormone secretagogue receptors (GHSR-1a) to alter food intake, fat utilization, and cellular proliferation. There is also evidence that ghrelin is involved in reproductive function. In the present study we used immunohistochemistry to investigate the presence of ghrelin and GHSR-1a in sheep reproductive tissues. In addition, we examined whether ghrelin and GHSR-1a protein expression is developmentally regulated in the adult and fetal ovine testis, and whether there is an association with markers of cellular proliferation, i.e. stem cell factor (SCF) and proliferating cell nuclear antigen (PCNA).

Methods

Antibodies raised against ghrelin and its functional receptor, GHSR-type 1a, were used in standard immunohistochemical protocols on various reproductive tissues collected from adult and fetal sheep. GHSR-1a mRNA presence was also confirmed by in situ hybridisation. SCF and PCNA immunoexpression was investigated in fetal testicular samples. Adult and fetal testicular immunostaining for ghrelin, GHSR-1a, SCF and PCNA was analysed using computer-aided image analysis. Image analysis data were subjected to one-way ANOVA, with differences in immunostaining between time-points determined by Fisher's least significant difference.

Results

In adult sheep tissue, ghrelin and GHSR-1a immunostaining was detected in the stomach (abomasum), anterior pituitary gland, testis, ovary, and hypothalamic and hindbrain regions of the brain. In the adult testis, there was a significant effect of season (photoperiod) on the level of immunostaining for ghrelin (p < 0.01) and GHSR-1a (p < 0.05). In the fetal sheep testis, there was a significant effect of gestational age on the level of immunostaining for ghrelin (p < 0.001), GHSR-1a (p < 0.05), SCF (p < 0.05) and PCNA (p < 0.01).

Conclusion

Evidence is presented for the presence of ghrelin and its receptor in various reproductive tissues of the adult and fetal sheep. In addition, the data indicate that testicular expression of ghrelin and its receptor is physiologically regulated in the adult and developmentally regulated in the fetus. Therefore, the ghrelin ligand/receptor system may have a role (endocrine and/or paracrine) in the development (cellular proliferation) and function of the reproductive axis of the sheep.
Combining metal oxide affinity chromatography (MOAC) and selective mass spectrometry for robust identification of in vivo protein phosphorylation sites
Authors: Wolschin Florian , Weckwerth Wolfram
Published: November 2005

Background

Protein phosphorylation is accepted as a major regulatory pathway in plants. More than 1000 protein kinases are predicted in the Arabidopsis proteome, however, only a few studies look systematically for in vivo protein phosphorylation sites. Owing to the low stoichiometry and low abundance of phosphorylated proteins, phosphorylation site identification using mass spectrometry imposes difficulties. Moreover, the often observed poor quality of mass spectra derived from phosphopeptides results frequently in uncertain database hits. Thus, several lines of evidence have to be combined for a precise phosphorylation site identification strategy.

Results

Here, a strategy is presented that combines enrichment of phosphoproteins using a technique termed metaloxide affinity chromatography (MOAC) and selective ion trap mass spectrometry. The complete approach involves (i) enrichment of proteins with low phosphorylation stoichiometry out of complex mixtures using MOAC, (ii) gel separation and detection of phosphorylation using specific fluorescence staining (confirmation of enrichment), (iii) identification of phosphoprotein candidates out of the SDS-PAGE using liquid chromatography coupled to mass spectrometry, and (iv) identification of phosphorylation sites of these enriched proteins using automatic detection of H3PO4 neutral loss peaks and data-dependent MS3-fragmentation of the corresponding MS2-fragment. The utility of this approach is demonstrated by the identification of phosphorylation sites in Arabidopsis thaliana seed proteins. Regulatory importance of the identified sites is indicated by conservation of the detected sites in gene families such as ribosomal proteins and sterol dehydrogenases. To demonstrate further the wide applicability of MOAC, phosphoproteins were enriched from Chlamydomonas reinhardtii cell cultures.

Conclusion

A novel phosphoprotein enrichment procedure MOAC was applied to seed proteins of A. thaliana and to proteins extracted from C. reinhardtii. Thus, the method can easily be adapted to suit the sample of interest since it is inexpensive and the components needed are widely available. Reproducibility of the approach was tested by monitoring phosphorylation sites on specific proteins from seeds and C. reinhardtii in duplicate experiments. The whole process is proposed as a strategy adaptable to other plant tissues providing high confidence in the identification of phosphoproteins and their corresponding phosphorylation sites.
ATP-sensitive potassium channel (KATPchannel) expression in the normal canine pancreas and in canine insulinomas
Authors: Donley Vicky R , Hiskett Erin K , Kidder Aimee C , Schermerhorn Thomas
Published: November 2005

Background

Pancreatic beta cells express ATP-sensitive potassium (KATP) channels that are needed for normal insulin secretion and are targets for drugs that modulate insulin secretion. The KATP channel is composed of two subunits: a sulfonylurea receptor (SUR 1) and an inward rectifying potassium channel (Kir6.2). KATP channel activity is influenced by the metabolic state of the cell and initiates the ionic events that precede insulin exocytosis. Although drugs that target the KATP channel have the expected effects on insulin secretion in dogs, little is known about molecular aspects of this potassium channel. To learn more about canine beta cell KATP channels, we studied KATP channel expression by the normal canine pancreas and by insulin-secreting tumors of dogs.

Results

Pancreatic tissue from normal dogs and tumor tissue from three dogs with histologically-confirmed insulinomas was examined for expression of KATP channel subunits (SUR1 and Kir6.2) using RT-PCR. Normal canine pancreas expressed SUR1 and Kir6.2 subunits of the KATP channel. The partial nucleotide sequences for SUR1 and Kir6.2 obtained from the normal pancreas showed a high degree of homology to published sequences for other mammalian species. SUR1 and Kir6.2 expression was observed in each of the three canine insulinomas examined. Comparison of short sequences from insulinomas with those obtained from normal pancreas did not reveal any mutations in either SUR1 or Kir6.2 in any of the insulinomas.

Conclusion

Canine pancreatic KATP channels have the same subunit composition as those found in the endocrine pancreases of humans, rats, and mice, suggesting that the canine channel is regulated in a similar fashion as in other species. SUR1 and Kir6.2 expression was found in the three insulinomas examined indicating that unregulated insulin secretion by these tumors does not result from failure to express one or both KATP channel subunits.
Mass Spectrometer Analysis of Paraffin-Naphthene Mixtures
Authors: Friedel R. A. , Logar A. F. , Shultz Janet L.
Published: November 2005

The mass spectrometer has been applied to type analyses in C6 to C8 paraffin-naphthene molecular-weight fractions. The platforming process has prompted the analysis of five component-types in these mixtures: Total paraffins, mono- and polysubstituted cyclopentanes, mono- and polysubstituted cyclohexanes.
The Reliability of Chemical Analysis
Authors: Schmidt R.
Published: November 2005

The reliability of chemical analysis is discussed in a general way, stress being laid on the necessity of using the methods of mathematical statistics in the design as well as in the evaluation of experiments (factorial design; analysis of variance; randomisation in time; control charts), carried out to develop analytical methods and procedures, in order to obtain reliable results in the application of the methods in practical analysis.
The Collaborative Assessment and Management of Suicidality versus Treatment as Usual: A Retrospective Study with Suicidal Outpatients
Authors: Jobes David A. , Wong Steven A. , Conrad Amy K. , Drozd John F. , Neal‐Walden Tracy
Published: November 2005

The Collaborative Assessment and Management of Suicidality (CAMS) is a novel clinical approach used to identify, assess, and manage suicidal outpatients (Jobes & Drozd, 2004). The results of a retrospective study evaluating the impact of CAMS versus treatment as usual (TAU) on suicidal outpatients are presented. Patients in the CAMS treatment group (n = 25) resolved their suicidality significantly more quickly than TAU patients (n = 30). CAMS was also significantly associated with decreased medical health care utilization in the 6 months after the start of suicide‐related mental health treatment. These results provide promising preliminary support for the effectiveness of CAMS and a foundation for prospective research.
Complicated Grief and Suicidal Ideation in Adult Survivors of Suicide
Authors: Mitchell Ann M. , Kim Yookyung , Prigerson Holly G. , Mortimer Mary Kay
Published: November 2005

While the prevalence of complicated grief has been demonstrated to be elevated in survivors of suicide, the association between complicated grief and suicidal ideation among adult suvivors of suicide has not been explored. The purpose of the present study is to examine the association between complicated grief and suicidal ideation in suicide survivors. The Inventory of Complicated Grief and the Beck Depression Inventory were administered to 60 adult survivors within 1 month of a death by suicide of a family member or significant other. Complicated grief was associated with a 9.68 (CI: 1.036, 90.417) times greater likelihood of suicidal ideation after controlling for depression, suggesting that syndromal complicated grief heightens vulnerability to suicidal ideation. Clinicians may provide more comprehensive assessments by recognizing the possibility of suicidal ideation in those with complicated grief.
An Evaluation of the Psychache Scale on an Offender Population
Authors: Mills Jeremy F. , Green Kate , Reddon John R.
Published: November 2005

This study examined the generalizability of a self‐report measure of psychache to an offender population. The factor structure, construct validity, and criterion validity of the Psychache Scale was assessed on 136 male prison inmates. The results showed the Psychache Scale has a single underlying factor structure and to be strongly associated with measures of depression and hopelessness and moderately associated with psychiatric symptoms and the criterion variable of a history of prior suicide attempts. The variables of depression, hopelessness, and psychiatric symptoms all contributed unique variance to psychache. Discussion centers on psychache's theoretical application to the prediction of suicide.
Zustandsbeobachter für periodische Signale: Anwendung zur aktiven Kompensation von motorerregten Karosserieschwingungen (State Observers for Periodic Signals: A Case Study in Active Vibration Control)
Authors: Bohn Christian , Karkosch Hans-Jürgen , Svaricek Ferdinand
Published: November 2005

Viele der im Automobil auftretenden Signale weisen aufgrund der periodischen Energieumsetzung des Verbrennungsmotors ebenfalls periodischen Charakter auf. Zur Regelung dieser Signale sind Zustandsbeobachter auf Basis eines Signalmodells, welches diese Periodizität nachbildet, sehr gut geeignet. Der vorliegende Beitrag zeigt dies am Beispiel der aktiven Reduzierung von motorseitig erzeugten und in die Karosserie eingeleiteten Schwingungen.
A Hybrid Evolutionary-Algebraic Approach to Optimal and Robust Controller Design (Hybride evolutionär-algebraische Verfahren für den Entwurf optimaler und robuster Regler)
Authors: Werner Herbert , Farag Adel
Published: November 2005

Modern control techniques – such as H
2 or H
∞ optimal controller design – offer powerful synthesis tools, provided the controller has the same order as the plant, and there are no constraints on the information structure of the feedback loop (e. g. decentralized control). If these assumptions do not hold – as is often the case in practical applications – the synthesis problem becomes non-convex and hard to solve. A frequently encountered situation is however that a synthesis problem is intractable, whereas the corresponding analysis problem is convex and easy to solve. In this case, it is often more efficient to use the easily available analysis results to guide a stochastic search for the solution, rather than to address the hard synthesis problem directly. In this paper, such an approach – based on a combination of algebraic tools from optimal control theory and evolutionary search techniques – is presented. Four benchmark problems representing “hard” control problems are used to illustrate the approach and to compare its efficiency with that of previously published solutions.
Menge aller robust stabilisierenden PID-Regler: Methodik und Software (Teil I) (The Set of All Robust Stabilizing PID Controllers: Methods and Software (Part I))
Authors: Bajcinca Naim , Hulin Thomas
Published: November 2005

Kürzlich wurde gezeigt, dass aufgrund einer Entkopplung der PID-Reglerparameter bei singulären Frequenzen das nichtkonvexe Hurwitz-Stabilitätsgebiet im PID-Parameterraum aus konvexen polygonalen Schnitten zusammengesetzt werden kann. Dadurch teilt sich die Aufgabe zum einen in die Bestimmung der Intervalle, in denen stabile Polygone existieren und zum anderen in die automatische Berechnung dieser Polygone. Das Verfahren kann sowohl auf zeitkontinuierliche als auch auf zeitdiskrete LTI Systeme einschließlich totzeitbehafteter Systeme angewendet werden. Es eignet sich besonders für den Entwurf von PID-Reglern, die robust gegenüber Parameterunsicherheiten in der Regelstrecke sind. Neben einiger weniger offener Fragen ist die zugrunde liegende Theorie weitgehend abgeschlossen. Dieser Artikel ist der erste in einer Reihe von dreien, die die neuesten Ergebnisse, Algorithmen und eine MATLAB®Toolbox für die schnelle Berechnung der Stabilitätsgebiete der PID-Regler darstellen.
Resistance, accumulation and transformation of selenium by the cyanobacterium Synechocystis sp. PCC 6803 after exposure to inorganic SeVI or SeIV
Authors: Gouget B. , Avoscan L. , Sarret G. , Collins Richard , Carrière M.
Published: November 2005

Our purpose was to investigate the ability of Synechocystis sp . PCC 6803, a photosynthetic prokaryote isolated from fresh water, to resist, incorporate and reduce the oxidized forms of selenium including selenite and selenate, the major selenium species present in aquatic systems. Selenium speciation and the chemical intermediates during selenium transformation were determined by X-ray absorption near edge structure (XANES) spectroscopy. The possible internalisation pathways involving selenium and the metabolic fate of selenate and selenite were examined. Selenate metabolism seemed to proceed via the sulfate reduction pathway resulting in the formation of the R-Se-H, R-Se-R and R-Se-Se-R species. The transformation of selenate to toxic amino acids may explain the high sensitivity of Synechocystis to selenate. Several mechanisms of selenium reduction seem to compete during selenite assimilation. A specific mechanism may transform internalised selenite into selenide and, subsequently induce the biosynthesis of selenoproteins. A non-specific mechanism may interfere with thiols, such as glutathione in the cell cytoplasm, or with proteins in the periplasm of the bacteria, notably thioredoxins. Several hypotheses concerning the complex transformation of selenium in Synechocystis could therefore be proposed.
Uranium(VI) complexation in cell culture medium: influence of speciation on Normal Rat Kidney (NRK-52E) cell accumulation
Authors: Carrière M. , Khodja H. , Avoscan L. , Carrot F. , Gouget B.
Published: November 2005

Uranium bioavailability and toxicity are closely linked to the metal's speciation in solution. However in biological fluids or in media classically used for cell culture – and subsequently for in vitro cell exposure –, uranium is rarely present as free-ion since these media contain non-negligible concentrations of potential ligands such as phosphate and bicarbonate but also co-ions such as calcium which can cause U(VI) complexes precipitation. The chemical form of uranium that is internalized in cells and interferes with biological processes is of major concern. Uranium toxicity and accumulation were evaluated in vitro on NRK-52E cells, model for rat renal proximal tubule. Uranium intracellular accumulation begins after 12 h exposure to 600 μM U(VI); toxicity appears as soon as cells accumulated 25 to 30 mg U/g protein. Modification of uranium speciation in the exposure medium induces great changes in toxicity and cell accumulation. Comparison of toxicity and accumulation results to theoretical uranium speciation, calculated with the J-Chess computer program, shows that free-ion concentration can not explain the total uranium intracellular accumulation. Low molecular weight U(VI) complexes, such as UO2(CO3)3
4− but also UO2PO4
− could be implicated in U(VI) cellular accumulation and toxicity.
Search for the decay of 229mTh by photon detection
Authors: Kasamatsu Yoshitaka , Kikunaga Hidetoshi , Takamiya Koichi , Mitsugashira Toshiaki , Nakanishi Takashi , Ohkubo Y. , Ohtsuki Tsutomu , Sato Wataru , Shinohara Atsushi
Published: November 2005

A search for the isomeric transition of 229mTh at 3.5 eV was made by photon detection with a low-noise photomultiplier for samples prepared by a rapid chemical separation from the parent nuclide 233U by means of an anion exchange method. The photon emission caused by the disintegration of 229mTh was not observed for 229Th nitric acid solution samples. From the experimental results, the limits of the half-life of 229mTh as dissolved in HNO3 solution are discussed.
Experimental measurements and nuclear model calculations on the excitation functions ofnatCe(3He,xn) and141Pr(p,xn) reactions with special reference to production of the therapeutic radionuclide140Nd
Authors: Hilgers K. , Shubin Yu. N. , Coenen Heinz H. , Qaim Syed M.
Published: November 2005

For production of the therapy related Auger electron emitting neutron deficient nuclide140Nd (T1/2= 3.37 d) two routes were investigated: the nuclear reactionnatCe(3He,xn)140Nd over the energy range from 15 to 36 MeV and the reaction141Pr(p, 2n)140Nd from 10 to 45 MeV. Some competing reactions leading to other Nd isotopes, namely139Nd and141Nd, as well as to139Ce were also investigated. Thin samples of cerium(IV)-oxide and praseodymium(III)-oxide were obtained by sedimentation and the conventional stacked-foil technique was used for cross section measurements. All the experimental data obtained in this work were compared with the results of theoretical calculations using the exciton model code ALICE-IPPE as well as with literature experimental data, if available. In general, good agreement between experimental and theoretical results was found. The theoretical thick target yields of all the product nuclides were calculated from the measured excitation functions. The theoretical thick target yield of140Nd over the energy rangeE3He= 35 → 20 MeV amounts to 12 MBq/μA·h and over the energy rangeEp= 30 → 15 MeV to 210 MBq/μA·h. A comparison of the two140Nd-producing reactions is presented.
A no-carrier-added72Se/72As radionuclide generator based on solid phase extraction
Authors: Jennewein M. , Qaim Syed M. , Kulkarni P. V. , Mason R. P. , Hermanne A. , Rösch Frank
Published: November 2005

72As-labelled radiopharmaceuticals could be a valuable resource for Positron Emission Tomography (PET). In particular, the long half-life of72As (T1/2= 26 h) facilitates the observation of long-term physiological or metabolic processes, such as the enrichment and distribution of antibodies in tumor tissue. This work describes the primary radiochemical separation of no-carrier-added (nca)72Se from cyclotron irradiated germanium targets and the development of a polystyrene type solid-phase extraction based72Se/72As radionuclide generator, avoiding the addition of any selenium carrier. The irradiated germanium target is dissolved in HFconcand selenium is reduced with hydrazine dihydrochloride. The nca72Se(0)is adsorbed on a solid-phase extraction cartridge, representing the generator column. The72As is eluted using various aqueous solvents with 40–60% yield and < 0.1%72Se content. To be able to study the radiopharmaceutical arsenic chemistry, subsequent chemical modification of the nca72As eluates to nca [72As]AsI3provides a versatile radioarsenic labelling synthon.
Chemical stabilization of recoil 56Mn in MnSO4-KClO4 mixed crystals following (n, γ) process
Authors: Mishra Shuddhodan P. , Vijaya M.
Published: November 2005

Stabilization of recoil 56Mn in mixed crystals of MnSO4KClO4 was studied with especial emphasis on isothermal annealing of neutron irradiated target. The results showed that *MnO4
- yield (%) varies linearly with the increase in perchlorate concentration from 0.100 to 0.500 mol fraction, reaching a maximum value of (89.0 ± 1.1)%. However, the value of intercept (P
0) obtained was (63.0 ± 1.2)%. Isothermal annealing of 56Mn in the present mixed crystal (MnSO4KClO4) of the two molar concentrations (i.e., 0.100 and 0.500 mol fraction) of perchlorate was studied at different temperatures for a desired length of time. The retention values increased with increasing temperature and time of annealing for both the samples. The values found for the two concentrations were (67.0 ± 1.0)% and (89.0 ± 1.1)%, respectively, at room temperature. Retention value increased gradually in the beginning but slowed down with a lapse of time and finally attained saturation within about 20 min of heating at 373 K in both cases. Limiting saturations were found to be (86.0 ± 1.0)% (max) for 0.100 molar concentration and (96.0 ± 0.8)% (max) for 0.500 molar concentration.

The rate of annealing was found to increase while the extent of annealing decreased. The recoil re-entry process obeys first order rate law and the energies of activation for the system (MnSO4KClO4) computed from the classical Arrhenius plots were found to be 0.15 ± 0.05 eV for 0.1 molar ratio and (2.5 ± 0.06)×10-2 eV for 0.5 molar ratio. The low value of activation energy indicates that there is a recombination of recoil fragments and participation of defect controlled reactions in thermal annealing, leading to higher saturation retention in 0.500 molar ratio. The results obtained are discussed in the light of vacancies created by the dopant and helping in the proposed recoils stabilization mechanism.
Radiochemical determination of 41Ca in nuclear reactor concrete
Authors: Hou Xiaolin
Published: November 2005

A simple analytical method for simultaneous determination of 41Ca and 90Sr in nuclear reactor concrete was developed. Different methods such as acid leaching and alkali fusion were investigated for the decomposition of the samples and for the separation of Ca and Sr from the matrix. Hydroxide and carbonate precipitation was used to separate Ca and Sr from the matrix elements as well as from each other. The chemical yields of the separation procedures for 41Ca and 90Sr are 80–90% and the decontamination factors for all interfering radionuclides are more than 104. The detection limits of the analytical method for 41Ca and 90Sr are 0.020 and 0.015 Bq, respectively. The methods developed here were used in the determination of 41Ca in heavy concrete from two concrete cores in the Danish research reactor DR-2.
Positron emission tomography for modelling of geochemical transport processes in clay
Authors: Richter Michael , Gründig Marion , Zieger Klaus , Seese Anita , Sabri Osama
Published: November 2005

The transport of water and salt solutions in unsaturated clay and clay rock was measured using the positron emission tomography (PET). The experimental device is described. KF marked with18F was used as conservative hydrodynamic tracer to image the flow profiles at different times. Homogeneous and heterogeneous flow regimes were identified. Hydrodynamic model parameters could be determined for the homogeneous regime. The results demonstrate the advantage of PET measurements for investigations of transport processes in geological matrices. They yield quantitative values of the spatial distribution in regard to the flow pattern inside the samples which are important for the validation and parameter estimation of geochemical transport models.
Case Report: Outbreak of Bumper Car Disease Caused by Anophryoides haemophila in a Lobster Holding Facility in Nova Scotia, Canada
Authors: Greenwood Spencer J. , Després Béatrice M. , Cawthorn Richard J. , Lavallée Jean , Groman David B. , Desbarats Adrian
Published: November 2005

This case report provides pathologic and confirmatory molecular characterization of an outbreak of bumper car disease caused by the scuticociliate Anophryoides haemophila in American lobster Homarus americanus, from a commercial holding facility in Nova Scotia, Canada. Although sporadically and anecdotally reported to be present in Atlantic Canada, this is the first report detailing observations from a natural outbreak of bumper car disease by gross and microscopic pathology and its positive identification by small subunit rRNA gene sequencing. Randomly amplified polymorphic DNA analysis confirmed that the genotype of the present outbreak isolate is identical to the original isolate of A. haemophila reported from Maine lobsters in 1993.
Growth, Dispersal, Mortality, and Contribution of Largemouth Bass Stocked into Chickamauga Lake, Tennessee
Authors: Hoffman Kevin J. , Bettoli Phillip W.
Published: November 2005

Marked fingerling largemouth bass Micropterus salmoides (both northern M. s. salmoides and Florida subspecies M. s. floridanus and their hybrid) were stocked into Chickamauga Lake, Tennessee, to enhance angling and introgress the Florida subspecies into the local gene pool. We evaluated mass marking and stocking success by sampling the stocked fish for 1 year poststocking. More than 128,000 fingerlings (35–64 mm total length) were immersed in a solution of 500 mg/L oxytetracycline (OTC) for 6 h and stocked into four embayments in the lake in spring 2002; two additional embayments served as controls and were not stocked (these embayments contained only wild, indigenous fish). In a blind test, 97% of sagittal otoliths were correctly scored as marked or unmarked. In a subsequent test, the OTC marks were clearly visible on every otolith removed from 240 OTC-treated bass held for 30 d. Age-0 largemouth bass were sampled with DC electrofishing gear at 7–19, 44–61, and 119–139 d after stocking, and sampling was conducted along 100-m transects within 1 km of the stocking sites in each embayment. Of all recaptures in the first sample, 31% occurred more than 600 m from the nearest stocking site, indicating rapid dispersal by some fish. Survival of stocked and wild age-0 largemouth bass was similar and low (4.5–6.9%) in two embayments; in the other two embayments, stocked fish survived at lower rates (0–4.3%) than wild fish (33.7–49.9%). Mean catches of all age-0 largemouth bass in the first sample were positively related to the number of fish stocked. By October 2002, the mean catch of all age-0 largemouth bass was similar among embayments. Contribution of stocked fish declined to approximately 2% (2 of 91 fish) the following spring. Cost per fingerling increased from US$0.35 at stocking to $12.00 at 140 d poststocking. Increasing the abundance of largemouth bass was not the primary objective of this stocking effort, but stocked fish will have to survive much better if managers hope to introgress Florida largemouth bass genes into the resident population genome.
Use of a Chase Boat for Increasing Electrofishing Efficiency for Flathead Catfish in Lotic Systems
Authors: Daugherty Daniel J. , Sutton Trent M.
Published: November 2005

Chase boats are commonly used to increase the catch efficiency of boat electrofishing for flathead catfish Pylodictis olivaris. However, use of a second vessel requires additional personnel, equipment, and budgetary resources that may influence decisions regarding sample planning efforts. While the efficacy of chase boats has been examined for lentic environments, no such studies have been documented for lotic systems. During 2002 and 2003, we compared low-voltage electrofishing catch efficiency with and without the use of a chase boat for three flow-rate classes in the lower St. Joseph River, Michigan. The median percentage of flathead catfish captured was significantly greater when a chase boat was used (60% of immobilized fish observed) than when a chase boat was not used (33%) at sampling locations with moderate flow rates (0.31–0.6 m/s). However, the catch efficiency with and without the use of a chase boat did not significantly differ at sampling locations with low (0–0.3-m/s) and high (>0.6-m/s) flow rates (range, 50–70%). Length-frequency distributions of flathead catfish were not significantly different between samples collected by electrofishing with or without a chase boat. Our results suggest that study objectives should be considered when determining whether to use a chase boat while boat electrofishing for flathead catfish in lotic systems.
The Response of Water Willow Justicia americana to Different Water Inundation and Desiccation Regimes
Authors: Strakosh Timothy R. , Eitzmann Jeffery L. , Gido Keith B. , Guy Christopher S.
Published: November 2005

American water willow Justicia americana has been planted in reservoirs to provide important littoral habitat for fish because of its ability to form dense stands, spread along shorelines, grow in water up to 1.2 m deep, and withstand harsh conditions. The response of water willow to periods of inundation or desiccation has not previously been quantified and is critical for evaluating its potential success in reservoirs. We tested the inundation response of plants at depths of 0.75, 1.50, and 2.25 m for 2, 4, 6, and 8 weeks. Response to desiccation was investigated using drying durations of 2, 4, 6, and 8 weeks. In addition, 2- and 4-week drying periods were tested separately in June, July, and August. Number of leaves, total height, and total dry weight were measured as indicators of plant condition. Condition rapidly declined after inundation for 4 weeks at all experimental depths and plants did not recover by the end of the experiment. A significant decrease in height and increase in leaf number was observed after 8 weeks of desiccation. Condition also declined from June to August during the second desiccation experiment. Overall, water willow appeared to be more resistant to desiccation than to inundation. A 5% overall mortality was observed for the desiccation trials versus a 69% overall mortality from the inundation trials. Even the shortest inundation duration in this study (2 weeks) resulted in mortality of 40% or more across all depth treatments and was probably due to light limitation. Our findings provide information that can be used to select candidate reservoirs for water willow establishment based on expected water-level fluctuations. Additionally, this information could be used to manage water levels in reservoirs where water willow currently provides important habitat for fish.
Characterization of Pearl Luster Pigments
Authors: Knoth M. , Miehe G. , Fuess H.
Published: November 2005

This paper presents current developments in pearl luster pigments. After a short introduction on the application of pigments, the synthesis and characterization of a ZrO2/SiO2 based pearlescent pigment will be described. The applied methods for characterization were ex situ x‐ray diffraction (XRD) of dried and calcined pigment powders, in situ XRD in a temperature range from 100°C up to 850°C and transmission electron microscopy (TEM) of thin cross‐sections. The XRD measurements were used for phase analysis, determination of cell parameters and average crystal grain sizes. A special preparation method was developed for TEM cross section specimens for platy like pigment particles. The microstructure, the interface between substrate and coating material and the particle sizes are described with high resolution TEM pictures of cross section specimens. The basic interest is the behaviour of the zirconium dioxide coating during sintering in order to achieve a condensation of the film without any further crystal grain growth.
Conditioning of Li(Ni,Co)O2 Cathode Materials for Rechargeable Batteries During the First Charge‐Discharge Cycles
Authors: Ehrenberg H. , Nikolowski K. , Bramnik N. , Baehtz C. , Buhrmester T. , Gross T.
Published: November 2005

As‐prepared Li(Ni,Co)O2 with good electrochemical performance is an insulator with low degree of cation disorder, i.e. Li and (Ni,Co) are distributed on different and alternating layers. Lithium extraction in the first cycle induces an irreversible first‐order phase transition into a metallic phase with a discontinuous change in the c/a ratio by 3.6% and an accompanied partial occupation of some of the vacant Li‐sites by Ni‐ions. The specific arrangement of those Ni‐ions on Li‐layers is proposed as a key feature for the good cycling behaviour of Li(Ni,Co)O2 based cathodes in rechargeable batteries.
Electrochemical Interface Doping in Organic Light Emitting Field Effect Transistors
Authors: Hepp A. , Heil H. , Schmechel R. , von Seggern H.
Published: November 2005

Electrochemical interface doping is introduced as a new concept for the realization of organic light‐emitting field‐effect transistors (O‐LEFTs). In a bottom contact tetracene transistor a 2–4 nm poly(ethylene‐oxide) layer with lithium triflate was inserted as interface layer between the gate‐oxide and the tetracene layer. For the first time a polymeric electrolyte is combined with “small molecule” functional material. The injection of both, holes and electrons allows for radiative recombination in the transistor channel. The onset of light emission occurs at a source‐drain‐voltage below 10 V and can be controlled by the gate voltage.
Continuum Mechanical Approach to Sintering of Nanocrystalline Zirconia
Authors: Zuo R. , Aulbach E. , Rödel J.
Published: November 2005

Nanocrystalline 3 mol % yttria‐stabilized zirconia was sinter‐forged isothermally under varying external uniaxial stresses. The applied uniaxial stresses were relatively low, compared to the intrinsic sintering stress of the material studied. Uniaxial sintering stresses and uniaxial viscosities were experimentally determined as function of density by means of a continuum mechanical approach which involves measuring the sintering rate of a free‐sintered specimen, and a specimen sintered under the application of an external uniaxial stress. The uniaxial viscosity increased strongly with density only in the final stage sintering regime. The magnitude of the uniaxial sintering stress exhibited a decrease with density.
Perspectives and Trends in Modern Materials Analysis
Authors: Ortner H.
Published: November 2005

Today, complex materials are the basis for key technologies which in turn are of major significance for the economic success and the social development in modern society. Materials analysis produces information on the composition and structure of materials without which a successful materials development as well as a stringent materials control would be impossible.

Modern materials analysis gives answers to four basic questions by use of an astonishing multitude of methods: What and how much? How structured? How bound? How distributed? These four questions are further elucidated and discussed in some detail. The materials analyst in industry faces a spectrum of further responsibilities which are also discussed.
Protein Posttranslational Modifications: The Chemistry of Proteome Diversifications
Authors: Walsh Christopher T. , Garneau‐Tsodikova Sylvie , Gatto Gregory J.
Published: November 2005

The diversity of distinct covalent forms of proteins (the proteome) greatly exceeds the number of proteins predicted by DNA coding capacities owing to directed posttranslational modifications. Enzymes dedicated to such protein modifications include 500 human protein kinases, 150 protein phosphatases, and 500 proteases. The major types of protein covalent modifications, such as phosphorylation, acetylation, glycosylation, methylation, and ubiquitylation, can be classified according to the type of amino acid side chain modified, the category of the modifying enzyme, and the extent of reversibility. Chemical events such as protein splicing, green fluorescent protein maturation, and proteasome autoactivations also represent posttranslational modifications. An understanding of the scope and pattern of the many posttranslational modifications in eukaryotic cells provides insight into the function and dynamics of proteome compositions.
A Theoretical Investigation into the Photophysical Properties of Ruthenium Polypyridine‐Type Complexes
Authors: Charlot Marie‐France , Pellegrin Yann , Quaranta Annamaria , Leibl Winfried , Aukauloo Ally
Published: November 2005

Excited states of ruthenium polypyridine‐type complexes have always attracted the interest of chemists. We have recently found evidence of a remarkable long‐lived excited state (30 μs) for a RuII complex containing a heteroditopic ligand that can be viewed as a fused phenanthroline and salophen ligand.1 To unravel this intriguing electronic property, we have used density functional theory (DFT) calculations to understand the ground‐state properties of [(bpy)2Ru(LH2)]2+, where LH2 represents N,N′‐bis(salicylidene)‐(1,10‐phenanthroline)diamine. Excited singlet and triplet states have been examined by the time‐dependent DFT (TDDFT) formalism and the theoretical findings have been compared with those for the parent complex [Ru(bpy)3]2+. The outstanding result is the presence of excited states lower in energy than the metal‐to‐ligand charge‐transfer states, originating from intraligand charge transfer (ILCT) from the phenolic rings to the phenanthroline part of the coordinated LH2. The spin density distribution for the lowest triplet state provides evidence that it is in fact the lowest triplet state of the free ligand. Correlation between the energy level diagram of orbitals for the ground state and that for the 3ILCT state clearly establishes that the ruthenium retains its formal RuII oxidation state. The quenching of the luminescence and the evidence of the long‐lived excited state observed for [(bpy)2Ru(LH2)]2+ are discussed in the light of the computational results.
Alkynylpyrenes as Improved Pyrene‐Based Biomolecular Probes with the Advantages of High Fluorescence Quantum Yields and Long Absorption/Emission Wavelengths
Authors: Maeda Hajime , Maeda Tomohiro , Mizuno Kazuhiko , Fujimoto Kazuhisa , Shimizu Hisao , Inouye Masahiko
Published: November 2005

The photochemical properties of various alkynylpyrene derivatives have been investigated in detail with a view to developing a new class of pyrene‐based biomolecular probes. The absorption maxima of the alkynylpyrenes were seen to be shifted to longer wavelengths compared with those of the unsubstituted parent pyrene. Fluorescence quantum yields of the alkynylpyrenes dramatically increased up to 0.99 in ethanol, and only slight quenching of the fluorescence occurred even under aerated conditions. The alkynylpyrenes have been successfully introduced into representative biomolecules such as peptides, proteins, and DNAs. The detectabilities of the labeled biomolecules were significantly improved, with the unique photochemical characteristics of the pyrene nucleus being maintained.
NMR Investigation of the Dihydrogen‐Bonding and Proton‐Transfer Equilibria between the Hydrido Carbonyl Anion [HRe2(CO)9]− and Fluorinated Alcohols
Authors: Donghi Daniela , Beringhelli Tiziana , D'Alfonso Giuseppe , Mondini Marta
Published: November 2005

The interaction of fluorinated alcohols with the anionic hydrido complex [HRe2(CO)9]− (1) has been investigated by NMR spectroscopy. According to the acidic strength of the alcohols, the interaction may result not only in the formation of dihydrogen‐bonded ROH⋅⋅⋅[HRe2(CO)9]− adducts 2, but also in proton transfer to give the neutral species [H2Re2(CO)9] (3). With the weaker acid trifluoroethanol (TFE) evidence for the occurrence of the dihydrogen‐bonding equilibrium was obtained by 2D 1H NOESY. The dependence of the hydride chemical shift on TFE concentration at different temperatures provided values for the constants of this equilibrium, from which the thermodynamic parameters were evaluated as ΔH°=−2.6(2) kcal mol−1, ΔS°=−9.3(2) cal mol−1 K−1. This corresponds to a rather low basicity factor (Ej=0.64). Variable‐temperature T1 measurements allowed the proton–hydride distance in adduct 2 a to be estimated (1.80 Å). In the presence of hexafluoroisopropyl alcohol (HFIP) simultaneous occurrence of both dihydrogen‐bonding and proton‐transfer equilibria was observed, and the equilibria shifted versus the protonated product 3 with increasing HFIP concentration and decreasing temperature. Reversible proton transfer between the alcohol and the hydrido complex occurs on the NMR timescale, as revealed by a 2D 1H EXSY experiment at 240 K. For the more acidic perfluoro‐tert‐butyl alcohol (PFTB) the protonation equilibrium was further shifted to the right. Thermal instability of 3 prevented the acquisition of accurate thermodynamic data for these equilibria. The occurrence of the proton‐transfer processes (in spite of the unfavorable pKa values) can be explained by the formation of homoconjugated RO⋅⋅⋅HOR− pairs which stabilize the alcoholate anions.
Water Dynamics in Ionomer Membranes by Field‐Cycling NMR Relaxometry
Authors: Perrin J.‐C. , Lyonnard S. , Guillermo A. , Levitz P.
Published: November 2005

The water dynamics of two types of ionomer membranes, the Nafion® and sulfonated polyimides, have been investigated by field‐cycling nuclear magnetic relaxation. This technique, applied to samples prepared at different water content, allows to characterize the proton motion at the time scale of the microsecond. The polyimides appear to behave as standard porous materials, whereas in the Nafion®, we have observed two different dynamical regimes related to a complex swelling process.
Non Linear State Space Modelling of a PEMFC
Authors: Hernandez A. , Hissel D. , Outbib R.
Published: November 2005

This paper will present a reduced input non linear state space model which describes the dynamic performance of a Proton Exchange Membrane air‐hydrogen fuel cell (PEMFC). The mathematical model is based mainly on gases physical behaviour, which leads to reactants partial pressure evolution within the channels. In order to obtain a more realistic model, liquid water formation within the fuel cell channels; and its influence on the fuel cell voltage is considered from a probabilistic approach. Model simulations under dynamic charge conditions are validated using results obtained from experiments done with a 500 W fuel cell existing in our laboratory (L2ES).
Technological advances in MRI measurement of brain perfusion
Authors: Duyn Jeff H. , van Gelderen Peter , Talagala Lalith , Koretsky Alan , de Zwart Jacco A.
Published: November 2005

Measurement of brain perfusion using arterial spin labeling (ASL) or dynamic susceptibility contrast (DSC) based MRI has many potential important clinical applications. However, the clinical application of perfusion MRI has been limited by a number of factors, including a relatively poor spatial resolution, limited volume coverage, and low signal‐to‐noise ratio (SNR). It is difficult to improve any of these aspects because both ASL and DSC methods require rapid image acquisition. In this report, recent methodological developments are discussed that alleviate some of these limitations and make perfusion MRI more suitable for clinical application. In particular, the availability of high magnetic field strength systems, increased gradient performance, the use of RF coil arrays and parallel imaging, and increasing pulse sequence efficiency allow for increased image acquisition speed and improved SNR. The use of parallel imaging facilitates the trade‐off of SNR for increases in spatial resolution. As a demonstration, we obtained DSC and ASL perfusion images at 3.0 T and 7.0 T with multichannel RF coils and parallel imaging, which allowed us to obtain high‐quality images with in‐plane voxel sizes of 1.5 × 1.5 mm2. J. Magn. Reson. Imaging 2005. Published 2005 Wiley‐Liss, Inc.