bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of [guanido‐13C]‐γ‐hydroxyarginine
Authors: Yoon Goo , Zabriskie T. Mark , Cheon Seung Hoon 
Published: December 2008

AbstractThis report describes an efficient method of synthesizing [guanido‐13C]‐γ‐hydroxyarginine HCl salt. Iodolactonization of N‐Boc‐protected allylglycine mainly provided the cis iodo compound 2. This was converted to an amine through azide 4. The amine 5 was reacted with N‐Boc‐protected [13C]thiourea to afford N‐Boc‐protected [13C]guanidine 6, which underwent base catalyzed ring opening. Removal of the N‐Boc group afforded [guanido‐13C]‐γ‐hydroxyarginine HCl salt 7 giving a 30% overall yield of the final product from N‐Boc protected allylglycine 1 in five steps. Copyright © 2008 John Wiley & Sons, Ltd.
De novo sequence analysis and intact mass measurements for characterization of phycocyanin subunit isoforms from the blue‐green alga Aphanizomenon flos‐aquae
Authors: Rinalducci Sara , Roepstorff Peter , Zolla Lello 
Published: December 2008

AbstractIn this work, partial characterization of the primary structure of phycocyanin from the cyanobacterium Aphanizomenon flos‐aquae (AFA) was achieved by mass spectrometry de novo sequencing with the aid of chemical derivatization. Combining N‐terminal sulfonation of tryptic peptides by 4‐sulfophenyl isothiocyanate (SPITC) and MALDI‐TOF/TOF analyses, facilitated the acquisition of sequence information for AFA phycocyanin subunits. In fact, SPITC‐derivatized peptides underwent facile fragmentation, predominantly resulting in y‐series ions in the MS/MS spectra and often exhibiting uninterrupted sequences of 20 or more amino acid residues. This strategy allowed us to carry out peptide fragment fingerprinting and de novo sequencing of several peptides belonging to both α‐ and β‐phycocyanin polypeptides, obtaining a sequence coverage of 67% and 75%, respectively. The presence of different isoforms of phycocyanin subunits was also revealed; subsequently Intact Mass Measurements (IMMs) by both MALDI‐ and ESI‐MS supported the detection of these protein isoforms. Finally, we discuss the evolutionary importance of phycocyanin isoforms in cyanobacteria, suggesting the possible use of the phycocyanin operon for a correct taxonomic identity of this species. Copyright © 2008 John Wiley & Sons, Ltd.
Identification of autoxidation oligomers of flavan‐3‐ols in model solutions by HPLC‐MS/MS
Authors: He Fei , Pan Qiu‐Hong , Shi Ying , Zhang Xue‐Ting , Duan Chang‐Qing 
Published: December 2008

AbstractAutoxidation of flavan‐3‐ols was carried out in aqueous/methanol model solutions under mildly acidic conditions (pH 6.0), and these autoxidation products were analyzed by using high performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (MS/MS). The results showed that (+)‐catechins and (−)‐epicatechins generated autoxidation reaction with each other to form a series of oligomers that had the same [M − H]− molecular ions (MS1) as those of natural procyanidins, but had completely different fragment ions (MS2). According to MS/MS analysis, the major fragments of these oligomers were derived not only from the retro‐Diels–Alder (RDA) dissociations on the C‐rings of the flavan‐3‐ol units, but also from the quinone‐methide (QM) cleavage of the interflavan linkages (IFL), and thus they were identified as B‐type dehydrodicatechins, B‐type dehydrotricatechins and A‐type dehydrotricatechins, respectively. The potential structures of their [M − H]− molecular ions and partial fragment ions were deduced on the basis of the MS/MS characterization and the oxidation of flavan‐3‐ols in previous reports. Some specific fragment ions were found to be very useful for identifying the autoxidation oligomers (the B‐type dehydrodicatechins at m/z 393, the B‐type dehydrotricatechins at m/z 681 and the A‐type dehydrotricatechins at m/z 725). Copyright © 2008 John Wiley & Sons, Ltd.
A possible mechanism for the co‐variability of the boreal spring Antarctic Oscillation and the Yangtze River valley summer rainfall
Authors: Sun Jianqi , Wang Huijun , Yuan Wei 
Published: December 2008

AbstractA significant correlation between the boreal spring Antarctic Oscillation (AAO) and the Yangtze River valley summer rainfall (YRVSR) has been found in previous studies, although the mechanisms that might lead to such far‐reaching teleconnection remain unresolved. In this study, one of possible mechanisms responsible for the co‐variability of the boreal spring AAO and the YRVSR is proposed. It follows that the convection activity over the region of the Maritime Continent serves as a bridge linking the boreal spring AAO and the YRVSR. This physical process can be described schematically as follows: during the boreal spring, a positive‐phase (negative‐phase) AAO is concurrent with a strong (weak) convection activity over the region of the Maritime Continent via anomalous meridional circulations along the central South Pacific and two meridional teleconnection wave train patterns, with one over the southern Indian Ocean at the lower level and the other along the central South Pacific at the upper level. Thereafter, the anomalous convection propagates northward along the seasonal cycle, and then changes the western Pacific subtropical high in the following seasons, consequently impacting on the summer rainfall in the Yangtze River valley. Copyright © 2008 Royal Meteorological Society
Updated and extended European dataset of daily climate observations
Authors: Klok E. J. , Klein Tank A. M. G. 
Published: December 2008

AbstractThe European Climate Assessment (ECA) dataset of daily observations, which has been widely used for studies on climate extremes, has been updated and extended. It now contains observational series of 2191 stations located in Europe and the Mediterranean (average inter‐station distance: ∼75 km). About 1200 precipitation series and 750 temperature series cover the period 1960–2000. For a small number of stations (<15%) air pressure, cloud cover, sunshine duration, snow depth and relative humidity series have been collected. All series are quality controlled and the homogeneity of the precipitation and temperature series is assessed. About 50% of the daily series are publicly available for climate studies through the website http://eca.knmi.nl. The main potential of the ECA dataset follows from its daily resolution, enabling studies of impact relevant climate extremes and variability. To guide these studies, climate indices calculated from the ECA series are presented on the website too. Besides, gridded versions of the daily ECA data are available for easy comparison with climate model simulations. A trend analysis for the diurnal temperature range (DTR) demonstrates the utility of the dataset. Seasonal and annual DTR trends were calculated for 333 homogeneous temperature series in ECA and a Europe average trend was estimated. In spring and summer, the DTR increased from 1979 to 2005, whereas in autumn and winter the DTR generally decreased. The European average trend in annual DTR was 0.09 °C decade−1. Copyright © 2008 Royal Meteorological Society
Inter‐annual and inter‐decadal variations of landfalling tropical cyclones in East Asia. Part I: time series analysis
Authors: Chan Johnny C. L. , Xu Ming 
Published: December 2008

AbstractThis paper is the first of a two‐part series that presents results of a comprehensive study of the variations in the annual number of landfalling tropical cyclones (ATCs) in various parts of East Asia during the period 1945–2004. The objective is to identify possible trends and cycles in such variations, from inter‐annual to inter‐decadal, and the possible reasons for such variations. The East Asian region is divided into three sub‐regions: South (south China, Vietnam and the Philippines), Middle (east China), and North (Korean Peninsula and Japan). Variations in the annual number on various time scales in each region are examined separately. Part I reports on the results of wavelet analyses of the time series of the annual number in each region, and Part II examines the possible reasons for the cycles identified in Part I.An important finding from the time series analysis is that none of the ATC time series shows a significant linear trend, which suggests that global warming has not led to a higher frequency of landfalling tropical cyclones or typhoons in any of the regions in Asia. Instead, each time series shows large inter‐annual (2–8 years) and multi‐decadal (16–32 years) variations. In some periods, the annual number of ATCs varies in unison among all regions of Asia. In others, one region would have an above‐normal number of landfalling events, while the other regions have below‐normal numbers. In general, at multi‐decadal time scales, the number of ATCs in each region correlates very well with that of the total number of tropical cyclones over the western North Pacific. Copyright © 2008 Royal Meteorological Society
Variabilities of the spring river runoff system in East China and their relations to precipitation and sea surface temperature
Authors: Chen Wen , Wang Lin , Xue Yongkang , Sun Shufen 
Published: December 2008

AbstractThe annual cycle and variabilities of the spring river runoff in East China (EC) at the continental scale and their relationship with precipitation, sea surface temperature (SST), and El Niño‐Southern Oscillation(ENSO) are investigated. Monthly mean data from 72 runoff stations and 160 precipitation stations in EC, covering a period between 1951 and 1983, are used for this study. The seasonal evolution of runoff depth is generally consistent with that of the rainfall but has more regional characteristics. The dominant spatial patterns and temporal variations of spring runoff and precipitation are studied with the empirical orthogonal function (EOF) analysis. The leading EOFs of spring runoff and precipitation show the intensity of runoff and precipitation in South China and are highly correlated with each other, indicating a direct response of runoff to precipitation, which is different from the summer situation. Statistic analysis suggests that the evolution of ENSO event may exert a strong influence on these two modes. The second EOFs of runoff and precipitation present a north‐south oscillation in EC with Nanling Mountain as the boundary and are also well correlated. These modes are highly related to the distribution of topography and may not be influenced by the ENSO. The third EOFs exhibit east–west oscillations in EC in both runoff and precipitation. The interdecadal relationship between spring precipitation/runoff and SST is further studied by singular value decomposition (SVD) analysis. The results indicate that the first coupled mode is dominant with the associated SST anomalies as an ENSO‐like interdecadal SST signal and indicates pronounced warming (SST) and wetting (runoff) trends in North China after the mid‐1970s, consistent with the observed trends of SST and runoff. The second coupled mode links the subtropical SST to the main spring runoff EOF mode in South China. Copyright © 2008 Royal Meteorological Society
Annual and seasonal surface air temperature trends in Mexico
Authors: Pavia Edgar G. , Graef Federico , Reyes Jorge 
Published: December 2008

AbstractMaximum and minimum surface air temperatures (Tmax, Tmin) throughout Mexico were analysed to look for a regional sign of climate change. Temperature (T) records were divided into two periods: early (1940–1969) and recent (1970–2004); and the analysis was performed for the four seasons plus the annual average. For these 20 cases, and for each of ∼1400 selected stations, time series were constructed and their linear trends (m) were obtained. The statistical significance of m was tested by posing the null hypothesis m = 0, i.e. that there was no trend. The length of the time series (n) considered for this test was the n‐effective (neff) that takes into account the fact that consecutive values of T have non‐zero correlation. The null hypothesis was rejected in less than 25% of the stations in all cases. The principal findings are: (1) Mexico warmed up during the recent period, and this warming was more generalized in Tmax than in Tmin and in summer than in the other seasons; (2) Mexico cooled down during the early period, and this cooling was more generalized in winter than in the other seasons; (3) In neither of these two cases El Niño‐Southern Oscillation (ENSO) seems to play any direct role; (4) In contrast to ENSO, the trends and phases of the Pacific Decadal Oscillation (PDO) are consequent in both cases: a warming trend at the beginning of the 1970s and a warm PDO phase prevailing during the recent warming period; as well as a cooling trend at the beginning of the 1940s and a cold PDO phase prevailing during the early cooling period; and (5) north‐western and central Mexico temperature trends often contrast with those of the rest of the country. Copyright © 2008 Royal Meteorological Society
A standard paleoclimatological approach to temperature reconstruction in historical climatology: an example from the Czech Republic, A.D. 1718–2007
Authors: Dobrovolný Petr , Brázdil Rudolf , Valášek Hubert , Kotyza Oldřich , Macková Jarmila , Halíčková Monika 
Published: December 2008

AbstractThis paper addresses a standard paleoclimatological approach to reconstructing temperatures in historical climatology. Weighted monthly temperature indices on a scale from − 3 to + 3, derived from documentary evidence for the period 1718–1850 in the Czech Lands, were used to create a series of seasonal (DJF, MAM, JJA, SON) and annual temperature indices as simple sums of indices from corresponding months. The period 1771–1850, when such indices overlap with instrumental measurements taken at Prague‐Klementinum, was used to calibrate and verify relations between indices and the temperatures measured, using linear regression models (LRM) evaluated by various statistical characteristics. The most accurate LRM performance was obtained for DJF, MAM and annual temperatures, while JJA and SON temperature results proved slightly less reliable. Reconstructed data for 1718–1770 were combined with measured data to create series of seasonal and annual temperatures for the Prague‐Klementinum station covering the period 1718–2007. Various problems in temperature reconstruction are further discussed: the completeness and quality of the index series, the expression of extreme temperatures, and the selection of a reference period for calibration. The suggested standard paleoclimatological approach lends more objectivity to both verification of reconstructed temperatures and the expression of uncertainties in reconstruction. Copyright © 2008 Royal Meteorological Society
Decadal‐scale changes in the tails of probability distribution functions of climate variables in Switzerland
Authors: Beniston Martin 
Published: December 2008

AbstractAn analysis of several Swiss climatological sites reveals that a substantial change in the behaviour of pressure, minimum and maximum temperature extremes has occurred in the past two decades. Extreme cold tails defined by the 10% quantiles of temperature drop by a factor of 2 or 3, while the upper tails (beyond the 90% quantile) exhibit a four‐ or five‐fold increase in all seasons. Pressure shows contrasting behaviour, with increases in wintertime highs and summertime lows, while precipitation shows little change. On the basis of the observed datasets, temperature biases related to extremes of pressure or precipitation have been computed, as well as for joint combinations of precipitation and pressure extremes. The most dominant bias is associated with periods without rainfall, during which temperatures are at least 1 °C warmer than otherwise. Changes in the behaviour of joint combinations of extreme pressure and precipitation regimes also have a discernible influence on temperatures. Copyright © 2008 Royal Meteorological Society
Dry spell trend analysis of Isfahan Province, Iran
Authors: Nasri M. , Modarres R. 
Published: December 2008

AbstractIn the present study the spatiotemporal trend analysis of the annual maximum dry spell length (AMDSL) and the annual number of dry spell periods (ANDSPs) of Isfahan Province in the center of Iran has been conducted based on daily rainfall records taken from 17 rain gauge stations. The autocorrelation functions (ACFs) of dry spell time series showed the randomness of dry spells. The use of Mann‐Kendall test for trend revealed two stations with significant negative trend of the AMDSL located in east and west of the province. The trend analysis of the ANDSP showed three stations with significant upward trend in east and one station with significant negative trend in the west of the province. The sequential Mann‐Kendall test showed an evidence of an individual abrupt change in the magnitudes of dry spells from 1980s, especially in eastern arid and semi‐arid regions of the province. However, the binomial and uniform distribution of Mann‐Kendall statistics reveals that individual trend in a region is not strong enough to conclude the large‐scale regional climatic effects on dry spell characteristics in the entire Isfahan Province. Copyright © 2008 Royal Meteorological Society
Are tourist arrivals stationary? Evidence from Singapore
Authors: Lee Chew Ging 
Published: December 2008

AbstractAugmented Dickey and Fuller and Kwiatkowski et al. tests are used to test for the non‐stationarity property of inbound tourists from 12 main source countries of Singapore. The tests provide evidence of stationarity for each of these countries, except India, Malaysia and the USA. The results for these three countries are inconclusive. The results demonstrate that exogenous shocks, such as severe acute respiratory syndrome and terrorist attacks, mainly have temporary negative effects on inbound tourists from the main source countries. The results also imply that the promotional campaign of Singapore and neighbouring countries can only have transitory positive or negative effects on the tourism industry of Singapore. Copyright © 2008 John Wiley & Sons, Ltd.
Moving best practice forward: Delphi characteristics, advantages, potential problems, and solutions
Authors: Donohoe Holly M. , Needham Roger D. 
Published: December 2008

AbstractIn the last 30 years, there has been increasing application of the Delphi technique to tourism research. However, mystification regarding Delphi characteristics and procedures is evident in the literature. Through critical examination, this paper seeks to demystify the Delphi and advance understanding of the technique, contribute to the evolution of methodological guidelines, and provide further guidance to tourism researchers. A generic Delphi procedure is introduced, a critical review of its advantages and potential problems is presented, and critical design decisions are identified. Expert panel design and management are emphasised through example and critical review. Copyright © 2008 John Wiley & Sons, Ltd.
Double‐blind trial of levodopa/carbidopa/entacapone versus levodopa/carbidopa in early Parkinson's disease
Authors: Hauser Robert A. , Panisset Michel , Abbruzzese Giovanni , Mancione Linda , Dronamraju Nalina , Kakarieka Algirdas ,   on behalf of the FIRST‐STEP Study Group
Published: December 2008

AbstractWe performed a 39‐week, randomized, double‐blind, multicenter study to compare the efficacy, safety, and tolerability of levodopa/carbidopa/entacapone (LCE, Stalevo) with levodopa/carbidopa (LC, Sinemet IR) in patients with early Parkinson's disease (PD). Four hundred twenty‐three patients with early PD warranting levodopa were randomly assigned to treatment with LCE 100/25/200 or LC 100/25 three‐times daily. The adjusted mean difference in total Unified Parkinson's disease Rating Scale (UPDRS) Parts II and III between groups using the analysis of covariance model (prespecified primary outcome measure) was 1.7 (standard error = 0.84) points favoring LCE (P = 0.045). Significantly greater improvement with LCE compared with LC was also observed in UPDRS Part II activities of daily living (ADL) scores (P = 0.025), Schwab and England ADL scores (blinded rater, P = 0.003; subject, P = 0.006) and subject‐reported Clinical Global Impression (CGI) scores (P = 0.047). There was no significant difference in UPDRS Part III or investigator‐rated CGI scores. Wearing‐off was observed in 29 (13.9%) subjects in the LCE group and 43 (20.0%) in the LC group (P = 0.099). Dyskinesia was observed in 11 (5.3%) subjects in the LCE group and 16 (7.4%) in the LC group (P = 0.367). Nausea and diarrhea were reported more frequently in the LCE group. LCE provided greater symptomatic benefit than LC and did not increase motor complications. © 2008 Movement Disorder Society
Therapeutic applications of glycosidic carbonic anhydrase inhibitors
Authors: Winum Jean‐Yves , Poulsen, Sally‐Ann , Supuran Claudiu T. 
Published: December 2008

AbstractThe zinc enzymes carbonic anhydrases (CAs, EC 4.2.1.1) are very efficient catalysts for the reversible hydration of carbon dioxide to bicarbonate and hence play an important physiological role. In humans, 16 different isozymes have been described, some of them being involved in various pathological disorders. Several of these isozymes are considered as drug targets, and the design of selective inhibitors is a long‐standing goal that has captured the attention of researchers for 40 years and has lead to clinical applications against different pathologies such as glaucoma, epilepsy, and cancer. Among the different strategies developed for designing selective CA inhibitors (CAIs), the “sugar approach” has recently emerged as a new attractive and versatile tool. Incorporation of glycosyl moieties in different aromatic/heterocyclic sulfonamide/sulfamides/sulfamates scaffolds has led to the development of numerous and very effective inhibitors of potential clinical value. The clinical use of a highly active carbohydrate‐based CA inhibitor, i.e., topiramate, constitutes an interesting demonstration of the validity of this approach. Other carbohydrate‐based compounds also demonstrate promising potential for the treatment of ophthalmologic diseases. This review will focus on the development of this emerging sugar‐based approach for the development of CAIs. © 2008 Wiley Periodicals, Inc. Med Res Rev, 29, No. 3, 419‐435, 2009
The job stress–job performance relationship in the social service encounter
Authors: Cano Cynthia Rodriguez , Sams Doreen , Schwartz Joe 
Published: December 2008

Abstract
The current study empirically examines job performance by considering perceived customer demands as a new antecedent of job stress (JS) and the mediating role of emotion‐focused coping (EFC) on the relationship of JS and physical consequences (PC), and in‐turn job performance. A mailed survey that solicited 2500 social service providers working in the United States rendered a useable random sample of 533. Regression analyses supported the hypothesized relationships. Findings suggest that emotions play an important role in the quality of the social service encounter evidenced by the mediating role of EFC in the relationship between JS and job performance. The introduction of an intervening variable (i.e., EFC) in the JS–job performance relationship extends affective event theory (AET). The findings offer management new insights into the service encounter by identifying a source of JS that creates barriers to value added benefit creation.
Copyright © 2008 John Wiley & Sons, Ltd.