bluuebunny/crossref_metadata_2025 huggingface dataset:
The t‐designs with prescribed automorphism group, new simple 6‐designs
Authors: Schmalz Bernd
Published: June 2007

We introduce an algorithm for the construction of a complete system of representatives of t‐designs with given parameters t − (v, k, λ) and prescribed full automorphism group A. It is based on the following observation published by Kramer and Mesner in 1976: The t − (v, k, λ) designs admitting automorphism group A are exactly the 0‐1‐solutions \documentclass{article}\pagestyle{empty}\begin{document}$ \overrightarrow x $\end{document} of the following system of linear equations

M are incidence matrices, which we compute by means of double cosets. Representing the set of all solutions of the above system of equations implicitly by a graph gives us the possibility either to extract the solutions explicitly or to compute their precise numbers, which often are very big. We use the lattice of overgroups of A in the full symmetric group Sv for the construction or enumeration of the isomorphism types of the t‐designs with full automorphism group A from these solutions. To the best of our knowledge our approach for the first time allows one to compute the precise number of isomorphism types or even these designs themselves for substantial numbers. We determined the (number of) isomorphism types for many known parameter sets and found new simple 6‐designs with parameters

and full automorphism group PΓL2(27). We constructed all isomorphism types of these designs; their precise numbers are 3,367,21 743,38 277, respectively. © 1993 John Wiley & Sons, Inc.
Maximal difference matrices of order q
Authors: Pott Alexander
Published: June 2007

Recently, A. B. Evans proved the following Theorem: There is a maximal set of (p − 3)/2 [(resp. (p − 1)/2] mutually orthogonal Latin squares of order p if p is a prime p ≡ 3 mod 4 (resp. p ≡ 1 mod 4). In this article I will give a slightly different proof using more geometric arguments and results of Rédei. Further, I discuss possible generalizations of Evans' Theorem to the case of Latin squares whose order is a prime power. © 1993 John Wiley & Sons, Inc.
Carnosine interaction with nitric oxide and astroglial cell protection
Authors: Nicoletti Vincenzo Giuseppe , Santoro Anna Maria , Grasso Giulia , Vagliasindi Laura Irene , Giuffrida Maria Laura , Cuppari Christian , Purrello Vittoria Spina , Stella Anna Maria Giuffrida , Rizzarelli Enrico
Published: June 2007

The neuropeptide carnosine (β‐amyloid peptide aggregation has been demonstrated. Carnosine protection against peroxynitrite damage is particularly relevant, but until now there has been no evidence of any direct interaction with nitric oxide. In this study we examined the protection that carnosine provides against nitric oxide (NO)–induced cell death in primary rat astroglial cell cultures treated with lipopolysaccharide (LPS) and interferon gamma (INFγ), a well‐known neurotoxic proinflammatory condition. A correlation was found between cell protection and NO free‐radical scavenging activity of carnosine. Moreover, by competitive spectrophotometric measurement and electrospray mass spectrometry analysis in cell‐free experiments, we demonstrated a direct interaction of the dipeptide with NO. A comparison of carnosine with its homologues or derivatives (homocarnosine and carcinine) as well as with its amino acid constituents (L‐histidine and β‐alanine) highlighted that only histidine showed significant scavenging activity. Therefore, carnosine shows direct NO‐trapping ability and may be a valuable multifunctional molecule in the treatment of neurodegenerative disorders. © 2007 Wiley‐Liss, Inc.
A new method of vegetation–climate classification in China
Authors: Yanling Sun , Xiaodong Yan , Deti Xie
Published: June 2007

Coefficient C is a synthetic index from the third correlative equation, which represents the state of moisture in a region and may be used for assigning vegetation zonality. The third correlative equation is a new equation concerning heat and water balance from knowledge of evaporation on land. In this article, coefficient C and accumulated temperature over 5 °C (AT5) are combined to predict the distribution of vegetation zones in China. Predictions of vegetation distribution are made using observational climate data interpolated into a 25 × 25 km grid.

The overall impression from examining the resulting vegetation map is that the location and distribution of vegetation zones in China are predicted fairly well. Comparison between the predicted vegetation map and the vegetation regionalization map are based on Kappa statistics and indicate very good agreement for the cold–temperate coniferous forest zone, the subtropical evergreen broadleaved forest zone, and the temperate mixed coniferous–broadleaved forest zone. Agreement is good for the warm–temperate deciduous broadleaved forest zone, the temperate steppe zone, the temperate desert zone, and the Tibetan high‐cold plateau zone. Agreement between the regionalization map and the produced map is fair for the tropical rainforest and monsoon forest zone.

Compared with those produced by the Holdridge, Thornthwaite, Penman, and the Kira models, as well as the Budyko method, the Kappa statistics in this article are all better except for the cold–temperate (boreal) coniferous forest zone and the temperate desert zone. The results are particularly superior for the Tibetan high‐cold plateau zone. Coefficient C provides important information for predicting the distribution of vegetation zones in China, and this article attempts to study vegetation–climate classification on a large scale using coefficient C and AT5. Copyright © 2007 Royal Meteorological Society
Features of the Caribbean low level jet
Authors: Whyte Felicia S. , Taylor Michael A. , Stephenson Tannecia S. , Campbell Jayaka D.
Published: June 2007

The Caribbean Low Level Jet (CLLJ) is shown to be a real and dominant climatological feature of the early summer Caribbean climate. It manifests as an intensification in the trade winds in the western Caribbean basin (70°W–80°W) with an east‐west axis along 15°N. It is confined to heights below 600 mb and has maximum wind speeds approaching 16 m/s near the surface. The study shows that there is variability in the strength and zonal extent of the CLLJ which can be related to zonal SST gradients between the eastern equatorial Pacific and the north tropical and/or equatorial Atlantic. When the gradient is driven by the Pacific (as in an EL Niño event) the CLLJ winds are intensified to the north and in its southwesternmost quadrant. When the winds are driven by the tropical north Atlantic there is uniform wind intensification about the jet axis. The CLLJ is also linked to a precipitation maximum over the near waters and along the Caribbean coast of Central America (up to 16°N) during June and more so, in July. There is evidence of variation at the northern extent of this wet zone depending on the ocean basin forcing the SST gradient. The CLLJ is also linked to moderate drying in the main Caribbean basin. Copyright © 2007 Royal Meteorological Society
Predictability of Sri Lankan rainfall based on ENSO
Authors: Zubair Lareef , Siriwardhana Manjula , Chandimala Janaki , Yahiya Zeenas
Published: June 2007

Investigating the year‐round rainfall of Sri Lanka provides understanding into the South Asian monsoon system as it compliments studies on the Indian summer monsoon. The El Niño‐Southern Oscillation (ENSO) is a primary mode of climate variability of this area. Here, the predictability of Sri Lanka rainfall based on ENSO is quantified based on composite analysis, correlations and contingency tables. The rainfall is modestly predictable based on ENSO during January–March, July–August and October–December. El Niño typically leads to wetter conditions during October to December and drier conditions during January to March and July to August on average. The correlations of ENSO indices with rainfall are statistically significant for October to December, January to March and July to August and an analysis based on contingency tables shows modest predictability. The use of ENSO indices derived from the central Pacific sea surfaces improves the predictability from January to June. The predictability in the mountain regions is diminished when garnering orographic rainfall. The predictability in the east is diminished during the cyclone season. The predictability based on ENSO for October to December rainfall is robust on a decadal scale while the predictability of January to March and July to August rainfall has acquired significance in recent decades. An ENSO‐based scheme that is adapted to each season and region, and takes account of decadal variations can thus provide skillful rainfall predictions. Copyright © 2007 Royal Meteorological Society
Use of seasonal climate information to predict coconut production in Sri Lanka
Authors: Peiris T. S. G. , Hansen J. W. , Zubair Lareef
Published: June 2007

Accurate forecasting of annual national coconut production (ANCP) is important for national agricultural planning and negotiating forward contracts. Climate and the long‐term trends (attributed to ‘technology’) are major factors that determine ANCP. The effect of climate on ANCP of the following year was studied for the seven agro‐ecological regions (AER's) in the principal coconut growing areas for the period 19502002. Climate was studied based on seasons aggregated by the monsoon calendar and by quarters that are consistent with the agricultural calendar. The use of quarterly seasons explained more of the variability of ANCP than the use of monsoon based seasons. January–March rainfall in all AER's and July–September rainfall in the wetter regions are positively correlated with the ANCP (p < 0.005). The technology effect was estimated using a log–linear trend model. The regression model integrates both climate and technology effects developed to predict ANCP with high fidelity (R2 = 0.94). The climate effect was estimated by regressing production data that had been de‐trended to remove the technology effects with quarterly rainfall in the year prior to harvest. The most significant predictors were found to be the quarterly rainfall from the AER's in the coconut growing regions that are designated as wet and intermediate. Representative rainfall from each quarter was used in a regression model with corrections for the technology effect. The correlation between observed and predicted values of the ANCP was 0.83 (p < 0.001). The prediction of ANCP for 2003 and 2004 gave errors of only 6.5 and 7.0%. The estimated value of ANCP for 2005 is 2715 million nuts, which is 12% higher than the mean. The lead time of the prediction extends to 15 months but it may be extended with the use of seasonal climate forecasts to 24 months. Copyright © 2007 Royal Meteorological Society
Complicated ENSO models do not significantly outperform very simple ENSO models
Authors: Halide Halmar , Ridd Peter
Published: June 2007

An extremely simple univariate statistical model called ‘IndOzy’ was developed to predict El Niño‐Southern Oscillation (ENSO) events. The model uses five delayed‐time inputs of the Niño 3.4 sea surface temperature anomaly (SSTA) index to predict up to 12 months in advance. The prediction skill of the model was assessed using both short‐ and long‐term indices and compared with other operational dynamical and statistical models. Using ENSO‐CLIPER(climatology and persistence) as benchmark, only a few statistical models including IndOzy are considered skillful for short‐range prediction. All models, however, do not differ significantly from the benchmark model at seasonal Lead‐3–6. None of the models show any skill, even against a no‐skill random forecast, for seasonal Lead‐7. When using the Niño 3.4 SSTA index from 1856 to 2005, the ultra simple IndOzy shows a useful prediction up to 4 months lead, and is slightly less skillful than the best dynamical model LDEO5. That such a simple model such as IndOzy, which can be run in a few seconds on a standard office computer, can perform comparably with respect to the far more complicated models raises some philosophical questions about modelling extremely complicated systems such as ENSO. It seems evident that much of the complexity of many models does little to improve the accuracy of prediction. If larger and more complex models do not perform significantly better than an almost trivially simple model, then perhaps future models that use even larger data sets, and much greater computer power may not lead to significant improvements in both dynamical and statistical models. Investigating why simple models perform so well may help to point the way to improved models. For example, analysing dynamical models by successively stripping away their complexity can focus in on the most important parameters for a good prediction. Copyright © 2007 Royal Meteorological Society
Freezing of lakes on the Swiss plateau in the period 1901–2006
Authors: Franssen H. J. Hendricks , Scherrer S. C.
Published: June 2007

Data of ice cover for deep Alpine lakes contain relevant climatological information since ice cover and winter temperature are closely related. For the first time, ice cover data from 11 lakes on the Swiss plateau have been collected and analysed for the period 1901–2006. The ice cover data used stem from systematic registration by individuals or groups (fishermen, an ice club and lake security service) and from several national, regional and local newspapers. It is found that in the past 40 years, and especially during the last two decades, ice cover on Swiss lakes was significantly reduced. This is in good agreement with the observed increase in the winter temperature in this period. The trend of reduced ice cover is more pronounced for lakes that freeze rarely than for the lakes that freeze more frequently. This agrees well with the stronger relative decrease in the probability to exceed the sum of negative degree days (NDD) needed for freezing the lakes that rarely freeze. The ice cover data are related with the temperature measurements such as the sum of NDD of nearby official meteorological stations by means of binomial logistic regression. The derived relationships estimate the probability of a complete ice cover on a lake as function of the sum of NDD. The sums of NDD needed are well related to the average depth of the lake (rNDD–Depth = 0.85). Diagnosing lake ice cover on the basis of the sum of NDD is much better than a prediction on the basis of a climatological freezing frequency. The variance of lake ice cover that cannot be explained by the sum of NDD is important for judging the uncertainty associated with climate reconstruction on the basis of data on lake ice cover. Copyright © 2007 Royal Meteorological Society
Initial speleothem results from western Flores and eastern Java, Indonesia: were climate changes from 47 to 5 ka responsible for the extinction of Homo floresiensis?
Authors: Westaway K. E. , Zhao J.‐x. , Roberts R. G. , Chivas A. R. , Morwood M. J. , Sutikna T.
Published: June 2007

Little is known about climate changes on Flores that influenced Homo floresiensis during the period of occupation of Liang Bua (95–12 ka) or the late‐surviving pygmy Stegodon lineage; both species became locally extinct at ca. 12 ka. Previous palaeoclimate analysis in this region has established that a prolonged dry period (ca. 45–12 ka) was followed by a rapid increase in rainfall, but lacks a firm chronology. Here we report initial results for stalagmites from western Flores and eastern Java. Using δ18O data from contemporaneous records, a series of isotopic shifts has been identified that reflects changes in the amount of rainfall, and in moisture sources. The isotopic signals from oxygen and carbon suggest differing ages for the rapid increase in rainfall, at ca. 13 ka and 17–16.5 ka, respectively. Thus, it cannot be determined from this evidence whether the abrupt disappearance of Stegodon and Homo floresiensis in western Flores was coincident with a major change in climate, or was caused instead, or as well, by a volcanic eruption at ca. 12 ka, or was related to the arrival of Homo sapiens at Liang Bua by ca. 10.5 ka. Copyright © 2007 John Wiley & Sons, Ltd.
Sediment mixing at Nonda Rock: investigations of stratigraphic integrity at an early archaeological site in northern Australia and implications for the human colonisation of the continent
Authors: David Bruno , Roberts Richard G. , Magee John , Mialanes Jerome , Turney Chris , Bird Michael , White Chris , Fifield L. Keith , Tibby John
Published: June 2007

Archaeological excavations in sediments dating to between 60 000 and 40 000 years ago are rare in Australia. Yet this is precisely the period in which most archaeologists consider that Aboriginal people arrived on the continent. In the few cases where such early sites have been investigated, questions have invariably been raised as to the reliability of stratigraphic associations between cultural items and the surrounding sediments. This paper describes a method for examining sediment mixing in a stratigraphic sequence using the optically stimulated luminescence (OSL) signals from individual sand‐sized grains of quartz. We apply this method to the archaeological site of Nonda Rock (north Queensland), in combination with radiocarbon dating of charcoal fragments, to construct chronologies for human occupation and for the preceding, culturally sterile, deposits. Our age estimates have implications for the timing of first human arrival in Australia. Copyright © 2007 John Wiley & Sons, Ltd.
The effect of the time and mode of application of gibberellic acid and inhibitors of gibberellin biosynthesis on the dormancy of potato tubers grown from true potato seed
Authors: Alexopoulos Alexios A , Akoumianakis Konstantinos A , Olympios Christos M , Passam Harold C
Published: June 2007

Gibberellic acid (GA3) and inhibitors of gibberellin biosynthesis (daminozide and chlormequat chloride) were applied to the foliage of potato plants grown from true seed (TPS) either once at two stages of plant development, 40 and 60 days after transplantation (DAT), or repeatedly at 10 day intervals starting from the same growth stages. When GA3 was applied towards the end of the vegetative cycle (either singly 60 DAT or repeatedly from the same date), it induced rapid breakage of tuber dormancy, a reduction in specific weight, a higher rate of respiration and increased weight loss during storage. Single applications of GA3 early in the vegetative cycle (40 DAT) had no effect on the weight loss and specific weight of tubers during storage, whereas repeated foliar applications of GA3 starting from the same stage resulted in the formation of tubers with a low specific weight and a high rate of weight loss during storage. However, the tubers from these treatments did not break dormancy uniformly, and, although in the early stages of storage they exhibited a high rate of respiration, this declined to the level of the control (no growth regulator applied). Although daminozide and chlormequat chloride did not affect the duration of tuber dormancy and had little or no effect on any of the other metabolic indicators studied, gibberellin is nevertheless implicated in dormancy breakage, and its application late in the growth cycle may be of practical value in cases where tubers are required for planting soon after harvest. Overall, tubers from TPS respond to plant growth regulator treatment in a similar way to those from plants grown from seed tubers. Copyright © 2007 Society of Chemical Industry
In‐house validation of a high‐performance liquid chromatography analytical method for quantification of ochratoxin A in unfermented grape juice
Authors: Murillo Ma Teresa , González‐Peñas Elena , Amézqueta Susana , de Cerain Adela López
Published: June 2007

A validated high‐performance liquid chromatography (HPLC) method with fluorescence detection for the quantitative analysis of ochratoxin A (OTA) in unfermented grape juice is described. Five millilitres of unfermented grape juice was mixed with 45 mL of PBS, and the pH was adjusted to 7.2. Then the mixture was filtered under vacuum through a glass microfibre filter and cleaned up with immunoaffinity columns prior to analysis by HPLC. Validation of the analytical method was based on the following criteria: selectivity, linearity, limit of detection and quantification, precision (within‐day and between‐day variability) and recovery and uncertainty estimation. Detection and quantification limits obtained were 0.02 µg L−1 and 0.05 µg L−1 respectively. The percentage recovery was 91.5% (RSD = 3.9). This method was applied to the measurement of 30 veraison stage unfermented grape juice samples. Copyright © 2007 Society of Chemical Industry
Radical scavenging activities, endogenous oxidative enzymes and total phenols in edible mushrooms commonly consumed in Europe
Authors: Ramírez‐Anguiano Ana Cristina , Santoyo Susana , Reglero Guillermo , Soler‐Rivas Cristina
Published: June 2007

Edible mushrooms are a good source of antioxidants. Methanol extracts of mushrooms such as Pleurotus sp., Agaricus bisporus, Morchella esculenta, Boletus edulis (approx. 2 mg mL−1) showed a high 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) scavenging activity close to 90%. Water extracts showed even higher antioxidant activity. In this case, B. edulis, Lentinus edodes and Amanita cesarea showed the highest 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid (ABTS) scavenging activity at approx. 0.14 mg mL−1. Other mushrooms such as Lactarius deliciosus and Cantharellus cibarius showed lower antioxidant activity in both extracts. Oxidative enzymes (peroxidases and polyphenol oxidases) present in the water fractions reduced their antioxidant activity by different extents since the phenols responsible for the antioxidant activity were not only those substrates of the oxidative enzymes. Other phenolic compounds and low‐molecular‐weight compounds were also involved in the antioxidant activity and differed depending on mushroom species. Copyright © 2007 Society of Chemical Industry
Sealed CO2 Laser Update – Product Trends Driven by Diverse Applications
Authors: Gaebler Frank , Schulze Matthias
Published: June 2007

Sealed CO2 lasers with powers up to 500 watts play a major role in many applications, in large part because they offer the lowest cost of ownership per watt of any industrial laser technology, together with the broad applicability of their midinfrared output. Two different types of sealed lasers service most of these applications ‐ CW lasers with average power of 100 watts or less, and pulsed models in the 100 to 500 watt range. This article reviews the different market demands for each of these laser types, and explores how manufacturers have responded to these needs.
Industrial Disk Lasers for Micro Material Processing – Compact Reliable Systems Conquer the Market
Authors: Kaiser Thomas , Albrecht Gunther John
Published: June 2007

The thin disk laser concept is a laser design for diode‐pumped solid‐state lasers, allowing the realization of laser systems with high output power, excellent efficiency and perfect beam quality. At present, multi‐kW thin disk lasers are commercially available for material processing. In the wide field of micro material processing, the demand is predominantly for several watts right up to 100 W of average output power.
Corrosion inhibitors performance for mild steel in CO2 containing solutions
Authors: Zavala Olivares G. , Hernández Gayosso M. J. , Mora Mendoza J. L.
Published: June 2007

The Electrochemical Impedance Spectroscopy (EIS), was used to evaluate and compare the behavior of three different corrosion inhibitors: quaternary amine (QA), oleic imidazoline (OI) and amino coco propionic acid (ACP), on the corrosion of mild steel in 3% NaCl solutions, saturated with CO2 gas, under static conditions. Two pH values: 3.8 and 5.5 were considered. Under the conditions considered in this work, the results indicated film formation at the metal surface, probable due to the formation of iron carbonate. This condition modified the values of the resistance and double layer capacitance of the system. In general terms, the ACP inhibitor exhibited better performance, compared to the QA and OI. During the impedance measurements with OI and ACP, some deviations were observed at high frequencies, indicating probably that the inhibitors adsorption occurs in different way to the QA inhibitor and the amine adsorption is weaker than the other two inhibitors adsorption.
Corrosion of reinforcing steel and low cycle fatigue behaviour
Authors: Apostolopoulos Ch. Alk. , Michalopoulos D.
Published: June 2007

Chloride induced corrosion of reinforcing steel can be highly detrimental and of great influence on the low cycle fatigue (LCF) characteristics. An experimental study conducted on BSt500s reinforcing steel, showed that the LCF and life expectancy were reduced considerably according to the level of corrosion. Low cycle strain controlled fatigue testing under ± 1 and ± 2.5% constant amplitude strain indicated that the corroded steel bars exhibit gradual reduction in available energy, number of cycles to failure and the load bearing ability. Formation of irregularities such as pits, notches and cavities occurred on the corroded steel surface and stress concentration points were developed which are highly localized at imperfections and especially at the rib bases. The experimental investigation of the corroded specimens subjected to LCF showed that the life expectancy, the remaining energy density and the strength properties were reduced considerably as a result of these irregularities combined with the mass loss and reduction of the exterior hard layer of martensite. Structural design capable of resisting seismic activity that does not account for the reduction of the load bearing ability and life expectancy as well as the cumulative plastic deformation of the steel reinforcement due to corrosion and loading history that a structure will be subjected in harsh climatic environments and ground oscillating motion could lead to serious and unpredictable performance.
The hydrogen permeation investigation of API X56 steel in sea mud
Authors: Zhu Y. , Huang Y. , Zheng C. , Yu Q.
Published: June 2007

It was found that the corrosion rate of steel in the sea mud with sulfate‐reducing bacteria (SRB) could be as high as 10 times of that in the sea mud without SRB. And the hydrogen permeation reaction would occur when metals were corroded. So it is necessary to investigate the effect of living SRB on hydrogen permeation in the sea mud. Cathodic potential was often added to metals in order to protect them. But hydrogen permeation could be affected by the cathodic potential. So it is also necessary to study the effect of cathodic potential on hydrogen permeation. In this paper, the hydrogen permeation actions of API X56 steel in the sea mud with and without SRB at corrosion and cathodic potential were studied with an improved Devanathan‐Stachurski's electrolytic cell. Experimental results showed that during the growth of SRB, the current density curve of hydrogen permeation was accordant with the growth curve of SRB. But the hydrogen permeation current density of API X56 steel hardly changed in the sterilized sea mud. Compared with the hydrogen permeation current density of API X56 steel in the sterilized sea mud, the hydrogen permeation of API X56 steel in the sea mud could be accelerated by living SRB. Experimental results also showed that the hydrogen permeation current density increased rapidly when the cathodic potential was added to the three‐electrode system of the cathodic cell, and then the hydrogen permeation current density could obtain a stable value slowly. So the cathodic potential added to the cathodic cell could accelerate hydrogen permeation.
Cavendish's crocodile and dark horse: The lives of Rutherford and Aston in parallel
Authors: Downard Kevin M.
Published: June 2007

Ernest Rutherford and Francis Aston were born a world apart but both would become two of the most influential physicists of their time. Their separate training, under the direction of J.J. Thomson at the Cavendish Laboratory, shaped their future and allowed both men to develop and apply their considerable skills in experimental physics. It also catalyzed their careers and ultimately led to each receiving a Nobel Prize. Although they had very different characters, Rutherford and Aston became close colleagues and confidants who spent considerable time together within the confines of the Cavendish Laboratory, at Trinity College, and elsewhere in Cambridge. They also traveled the world in company, usually as part of a group or British delegation of scientists attending conferences and meetings overseas. This article parallels the lives of the two men. It describes how they came to work at the Cavendish, their scientific accomplishments and accolades, and their activities and interactions away from the laboratory. © 2007 Wiley Periodicals, Inc., Mass Spec Rev 26:713–723, 2007
Low p38 MAPK and JNK activation in cultured hepatocytes of DRH rats; a strain highly resistant to hepatocarcinogenesis
Authors: Honmo Satoshi , Ozaki Atsuko , Yamamoto Masahiro , Hashimoto Norikazu , Miyakoshi Masaaki , Tanaka Hiroki , Yoshie Masumi , Tamakawa Susumu , Tokusashi Yoshihiko , Yaginuma Yuji , Kasai Shinichi , Ogawa Katsuhiro
Published: June 2007

DRH rats are a hepatocarcinogenesis‐resistant strain isolated from hepatocarcinogenesis‐sensitive Donryu rats, and the liver of DRH shows less histological damage and fewer/smaller neoplastic hepatic lesions by the treatment with hepatocarcinogens. To investigate the mechanism of the resistance, the properties of hepatocytes of DRH and Donryu were compared. In primary culture, DRH hepatocytes exhibited higher proliferation and less apoptosis than Donryu hepatocytes in the presence of EGF and insulin. However, such difference was not correlated to the degree of DNA damage associated with cell culture or cell cycle checkpoint function. Although the mitogen‐activated protein kinases [EGF receptor (EGFR) and extracellular signal regulating kinases (ERK1/2)] were activated to the same degree, the stress‐activated protein kinases [p38 mitogen‐activated protein kinase (p38) and c‐jun N‐terminal kinase (JNK)] were activated to a lesser degree in the DRH hepatocytes. Treatment with 2‐acetylaminofluorene (2‐AAF) in vivo also resulted in less JNK and p38 activation in the DRH livers. Furthermore, apoptosis signal‐regulating kinase 1 (ASK1) was inhibited by the lysate from the DRH but not by the Donryu hepatocytes. The low activation of the stress‐activated protein kinases may be linked to the resistance to cellular stress, which may underlie the hepatocarcinogenesis‐resistance in DRH rats. © 2007 Wiley‐Liss, Inc.
Effect of age on geriatric depression scale performance in Parkinson's disease
Authors: Weintraub Daniel , Saboe Kirsten , Stern Matthew B.
Published: June 2007

The purpose of this study was to compare the validity of the 15‐item Geriatric Depression Scale (GDS‐15) in nonelderly (<65 years), young‐elderly (age, 65–75), and old‐elderly (>75 years) patients with Parkinson's disease (PD). 57 nonelderly, 88 young‐elderly, and 81 old‐elderly PD patients were administered the GDS‐15 and the Structured Clinical Interview for DSM‐IV depression module. Receiver‐operating characteristic (ROC) curves were plotted for GDS‐15 scores against a DSM‐IV diagnosis of major or minor depression. The discriminant validity of the GDS‐15 was high for nonelderly, young‐elderly, and old‐elderly subjects (ROC area under curve = 0.92, 0.91, and 0.95, respectively), with optimal dichotomization at a cut‐off of 4/5 (85% sensitivity and 84% specificity in nonelderly; 89% sensitivity and 82% specificity in young‐elderly) and 5/6 (90% sensitivity and 90% specificity in old‐elderly). In conclusion, the GDS‐15 has comparable validity in younger and older PD patients, suggesting its appropriateness as a depression screening instrument in PD patients of all ages. © 2007 Movement Disorder Society
Prevalence of nonmotor symptoms in Parkinson's disease in an international setting; Study using nonmotor symptoms questionnaire in 545 patients
Authors: Martinez‐Martin Pablo , Schapira Anthony H.V. , Stocchi Fabrizio , Sethi Kapil , Odin Per , MacPhee Graeme , Brown Richard G. , Naidu Yogini , Clayton Lisa , Abe Kazuo , Tsuboi Yoshio , MacMahon Dough , Barone Paolo , Rabey Martin , Bonuccelli Ubaldo , Forbes Alison , Breen Kieran , Tluk Susanne , Olanow C. Warren , Thomas Sue , Rye David , Hand Annette , Williams Adrian J. , Ondo William , Chaudhuri K. Ray
Published: June 2007

2006, there was, no single instrument (questionnaire or scale) for attempting a comprehensive assessment of the wide range of nonmotor symptoms (NMS) of Parkinson's disease (PD). The PD nonmotor group, a multidisciplinary group of experts including patient group representatives developed and validated the NMS screening questionnaire (NMSQuest) comprising 30 items. The NMSQuest is a self completed screening tool designed to draw attention to the presence of NMS. In this paper, we present the results gathered from 545 patients using the definitive version of the NMSQuest highlighting the prevalence of the wide range of NMS flagged in the NMSQuest from consecutive PD patients in an international setting. © 2007 Movement Disorder Society
Dynamic changes in the localization of five members of the methyl binding domain (MBD) gene family during murine and bovine preimplantation embryo development
Authors: Ruddock‐D'Cruz Nancy T. , Xue Jun , Wilson Katrina J. , Heffernan Corey , Prashadkumar Sivachelvi , Cooney Melissa A. , Sanchez‐Partida L. Gabriel , French Andrew J. , Holland Michael K.
Published: June 2007

There are five methyl binding domain (MBD) proteins characterized by a methyl CpG‐binding domain. Four MBD proteins (MeCP2 and MBDs 1–3) are linked to transcriptional repression and one (MBD4), to DNA repair. During preimplantation development, the embryo undergoes global demethylation following fertilization and selective remethylation following the maternal to zygotic transition (MZT). This study characterized changes in MBD mRNA expression and protein localization during both murine and bovine preimplantation development. These species were selected because they undergo MZT at different developmental stages. Gene expression profiling during preimplantation development detected the presence of all MBDs examined, although stage and species‐specific differences were observed. MBD2 was not expressed in murine or bovine oocytes and MeCP2 was not detected in murine blastocysts, subcellular protein localization was found to vary at time points critical in development. Most MBDs showed species‐specificity in localization patterns and differences were found between individual MBDs. MBD1 localization is consistent with a novel role during MZT for both species. MBD3, known to play a crucial role in murine embryogenesis, was highly localized to the nucleus before and after, but not during the MZT in the bovine. MBD2, MBD4, and MeCP2 show varying patterns of localization which indicate possible roles in the early cleavage stages and in inner cell mass differentiation. Further experiments are currently underway to define discreet functional roles for specific MBDs during bovine preimplantation embryogenesis. Mol. Reprod. Dev. 75: 48–59, 2008. © 2007 Wiley‐Liss, Inc.
Transient transgene transmission to piglets by intrauterine insemination of spermatozoa incubated with DNA fragments
Authors: Wu Zhenfang , Li Zicong , Yang Jinzeng
Published: June 2007

An efficient and low‐cost production of transgenic pigs has significant applications to the pig industry and biomedical science. Generation of transgenic pig by sperm‐mediated gene transfer (SMGT) was inexpensive and convenient, and reported with high efficiency. To test the method of SMGT in pigs, we employed deep post‐cervical intrauterine insemination of incubated spermatozoa in this study. A test of sperm motility of semen from nine Landrace boars after incubation with radioactively labeled DNA construct indicated that DNA uptake of the sperm was highly correlated with sperm motility at the time of collection. DNA concentration of 50 and 300 µg per one billion sperm was incubated with washed high‐motility sperm at 17°C for 2 hr. Twenty one hybrid gilts and sows of Meishan crossed with Large White were inseminated with transgene‐incubated sperm and produced 156 piglets. Transgene DNA sequences were identified in 31 piglets by PCR amplification of genomic DNA isolated from piglet ears at the age of 3 days. The deep intrauterine insemination had a higher rate of positive transgenic piglets than regular insemination (29.6% of 98 piglets vs. 3.4% of 58 piglets). However, the exogenous transgene DNA was not detected in any piglets at the age of 70–100 days. Therefore, the results further demonstrated that transgene through incubation with spermatozoa was mostly transiently transmitted to the offspring at early growing stage and lost in adulthood, which may result from episomal DNA replications during cell divisions only at the early stage of development. Mol. Reprod. Dev. 75: 26–32, 2008. © 2007 Wiley‐Liss, Inc.
Evidence‐based management for polymyalgia rheumatica for rheumatology practitioners, nurses and physiotherapists
Authors: Hennell Sheena , Busteed S. , George E.
Published: June 2007

Evidence‐based practice is an increasingly popular term, used in a variety of clinical settings and situations. Practitioners are encouraged to use best evidence as part of clinical decision‐making when caring for individual patients. This evidence, combined with practitioner expertise and knowledge, aims to inform practice, ensuring that accurate, effective and safe treatment options are utilized. Copyright © 2007 John Wiley & Sons, Ltd.
Antipyretic drug use in children in French office based medical practice
Authors: Deligne Jean , Grimaldi Lamiae , Jonville‐Béra Annie‐Pierre , Giraudeau Bruno , Blum‐Boisgard Claudine , Autret‐Leca Elisabeth
Published: June 2007

Purpose

To analyse antipyretics (APs) prescriptions profile in children, particularly the frequency of AP combinations.

Methods

APs (acetylsalicylic acid, paracetamol, ibuprofen or ketoprofen) prescribed to children below 12 years and refunded by a public health insurer in 2003, throughout France, were examined.

Results

A total of 513 034 prescriptions were refunded for 240 720 children. The mean number of AP prescriptions per child was the highest in children aged 6 months to 2 years. Paracetamol was the main AP prescribed, but its prescription declined with age, from 90.8% below 3 months old to 57.4% between 6 and 12 years old. Ibuprofen‐only prescriptions were rare below 3 months and maximal between 2 and 6 years. The ibuprofen/paracetamol combination was prescribed from 6 months old, and its frequency was maximal between 2 and 6 years old (21.7%).

Conclusions

The clear predominance of paracetamol prescriptions suggests that French prescribers are relatively aware of the relative risk‐benefit ratio of the different APs. Studies are required to determine if the APs are prescribed to be used alternately or when a monotherapy fails. Guidelines to manage fever in children are needed in France to restrict APs combination to the case of paracetamol failure. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and characterization of a polyfluorene containing carbazole and oxadiazole dipolar pendent groups and its application to electroluminescent devices
Authors: Yuan Mao‐Chuan , Shih Ping‐I , Chien Chen‐Han , Shu Ching‐Fong
Published: June 2007

We have synthesized a blue‐light‐emitting polyfluorene (PF) derivative (PF‐CBZ‐OXD) that presents bulky hole‐transporting carbazole and electron‐transporting oxadiazole pendent groups functionalized at the C‐9 positions of alternating fluorene units. The results from photoluminescence and electrochemical measurements indicate that both the side chains and the PF main chain retain their own electronic characteristics in the copolymer. An electroluminescent device incorporating this polymer as the emitting layer was turned on at 4.5 V; it exhibited a stable blue emission with a maximum external quantum efficiency of 1.1%. Moreover, we doped PF‐CBZ‐OXD and its analogue PF‐TPA‐OXD with a red‐light‐emitting iridium phosphor for use as components of phosphorescent red‐light emitters to investigate the effect of the host's HOMO energy level on the degree of charge trapping and on the electrophosphorescent efficiency. We found that spectral overlap and individual energy level matching between the host and guest were both crucial features affecting the performance of the electroluminescence devices. Atomic force microscopy measurements indicated that the dipolar nature of PF‐CBZ‐OXD, in contrast to the general nonpolarity of polydialkylfluorenes, provided a stabilizing environment that allowed homogeneous dispersion of the polar iridium triplet dopant. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2925–2937, 2007
White electroluminescence from a single polymer: A blue‐emitting polyfluorene incorporating orange‐emitting benzoselenadiazole segments on its main chain
Authors: Chien Chen‐Han , Shih Ping‐I , Shu Ching‐Fong
Published: June 2007

We have developed efficient white‐light‐emitting polymers through the incorporation of low‐bandgap orange‐light‐emitting benzoselenadiazole (BSeD) moieties into the backbone of a blue‐light‐emitting bipolar polyfluorene (PF) copolymer, which contains hole‐transporting triphenylamine and electron‐transporting oxadiazole pendent groups. By carefully controlling the concentrations of the low‐energy‐emitting species in the resulting copolymers, partial energy transfer from the blue‐fluorescent PF backbone to the orange‐fluorescent segments led to a single polymer emitting white light and exhibiting two balanced blue and orange emissions simultaneously. Efficient polymer light‐emitting devices prepared using this copolymer exhibited luminance efficiencies as high as 4.1 cd/A with color coordinates (0.30, 0.36) located in the white‐light region. Moreover, the color coordinates remained almost unchanged over a range of operating potentials. A mechanistic study revealed that energy transfer from the PF backbone to the low‐bandgap segments, rather than charge trapping, was the main operating process involved in the electroluminescence process. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2938–2946, 2007
Hot spots—A review of the protein–protein interface determinant amino‐acid residues
Authors: Moreira Irina S. , Fernandes Pedro A. , Ramos Maria J.
Published: June 2007

Proteins tendency to bind to one another in a highly specific manner forming stable complexes is fundamental to all biological processes. A better understanding of complex formation has many practical applications, which include the rational design of new therapeutic agents, and the analysis of metabolic and signal transduction networks. Alanine‐scanning mutagenesis made possible the detection of the functional epitopes, and demonstrated that most of the protein–protein binding energy is related only to a group of few amino acids at intermolecular protein interfaces: the hot spots. The scope of this review is to summarize all the available information regarding hot spots for a better atomic understanding of their structure and function. The ultimate objective is to improve the rational design of complexes of high affinity and specificity as well as that of small molecules, which can mimic the functional epitopes of the proteic complexes. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Dynamics of heteropentameric nicotinic acetylcholine receptor: Implications of the gating mechanism
Authors: Szarecka Agnieszka , Xu Yan , Tang Pei
Published: June 2007

The dynamics characteristics of the currently available structure of Torpedo nicotinic acetylcholine receptor (nAChR), including the extracellular, transmembrane, and intracellular domains (ICDs), were analyzed using the Gaussian Network Model (GNM) and Anisotropic Network Model (ANM). We found that a symmetric quaternary twist motion, reported previously in the literature in a homopentameric receptor (Cheng et al. J Mol Biol 2006;355:310–324; Taly et al. Biophys J 2005;88:3954–3965), occurred also in the heteropentameric Torpedo nAChR. We believe, however, that the symmetric twist alone is not sufficient to explain a large body of experimental data indicating asymmetry and subunit nonequivalence during gating. Here we report our results supporting the hypothesis that a combination of symmetric and asymmetric motions opens the gate. We show that the asymmetric motion involves tilting of the TM2 helices. Furthermore, our study reveals three additional aspects of channel dynamics: (1) loop A serves as an allosteric mediator between the ligand binding loops and those at the domain interface, particularly the linker between TM2 and TM3; (2) the ICD can modulate the pore dynamics and thus should not be neglected in gating studies; and (3) the F loops, which are peculiarly longer and poorly‐conserved in non‐α‐subunits, have important dynamical implications. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Effect of the oxygen nonstoichiometry on the structure and magnetic properties of Nd2CoMnO6+δ double perovskites
Authors: Sazonov A. P. , Troyanchuk I. O. , Sikolenko V. V. , Szymczak H. , Bärner K.
Published: June 2007

The properties of Nd2CoMnO6+δ (δ up to 0.12) were investigated by means of neutron powder diffraction and magnetization measurements. It is found that the samples exhibit partial ordering of Co and Mn ions which strongly affects the magnetic properties. Ionic disorder increases with the oxygen content. According to neutron diffraction the stoichiometric and nonstoichiometric samples show ferromagnetic components which decreases as the oxygen content increases. The magnetization study of the strongly oxidized sample reveals a metamagnetic behavior. It is assumed that metamagnetism results from clusters with short‐range antiferromagnetic order. Enhancement of the oxygen content leads to a conversion of Co2+ into low spin Co3+ and the appearance of a cationic vacancy which destroys the ionic order and stabilizes the overall antiferromagnetic behavior. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strong quenching of Y2SiO5:Pr3+ nanocrystal luminescence by praseodymium nonuniform distribution
Authors: Zhmurin P. N. , Znamenskii N. V. , Yukina T. G. , Malyukin Yu. V.
Published: June 2007

Using site‐selective and time‐resolved spectroscopy technique in combination with single molecular spectroscopy technique the concentration quenching of the 1D2 luminescence of Pr3+ ions has been examined in Y2SiO5:Pr3+ nanocrystals. The direct comparison of the data obtained for nano‐ and bulk Y2SiO5:Pr3+ crystals has revealed that the concentration threshold of luminescence quenching is strikingly low for nanocrystals. In this case the ordered stage in the 1D2 luminescence decay has been observed at anomalously low Pr concentration (0.5 at%). This effect is caused by the preferred Pr accumulation at the nanocrystal periphery that provides the relaxation of elastic tension arising due to the difference of ionic radii of Pr3+ and Y3+. The temporal behavior of the 1D2 luminescence decay in the disordered stage shows that the concentration quenching is caused by the cooperative cross‐relaxation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)