bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plant distribution patterns in Germany – Will aliens match natives?
Authors: Kühn I. , Brandl R. , May R. , Klotz St. 
Published: December 2003

AbstractUsing data on the distribution of the German vascular flora and a wide selection of environmental data we address questions regarding native and alien plant distribution patterns. We found highly significant positive relationships between plant species richness of natives and aliens on three spatial scales (c. 100 km2, c. 1,000 km2, c. 10,000 km2). Given the results of major axis regressions on log‐transformed data, we conclude that alien species richness increases overproportionately compared to native species richness. To determine common factors for plant richness patterns, we used a principal component analysis (PCA) to reduce the number of environmental variables. The principal components were used in a multiple regression as independent variables to model plant species richness of aliens and natives, corrected for spatial autocorrelation. The diversity of geological substrates is considered most important for native and alien plant species richness. Furthermore, area of loess subsoils is important for archaeophyte richness, urbanisation is important for neophyte richness.Comparisons of similarity matrices between natives and aliens using standardised similarities as well as Simpsons similarities of randomly selected grid cells showed a positive correlation. Similarity patterns provided by native plant species are traced by archaeophytes but not followed by neophytes. Similarities of archaeophytes were significantly higher than those of natives whereas similarities of neophytes where significantly lower than those of natives. Therefore, we concluded that archaeophytes lead to homogenisation of the German flora but are mainly plants of arable fields that are homogeneous due to human land use. Neophytes, however, did not lead to homogenisation but increase local biodiversity.
Patterns of species composition and species richness in most (ash‐alder) forests of northern Germany (Schleswig‐Holstein)
Authors: Härdtle W. , von Oheimb G. , Meyer H. , Westphal Chr. 
Published: December 2003

AbstractIn this study we analysed the relationships between the species composition/richness of moist forests and environmental variables (light conditions, soil pH, S‐value, base saturation, C/N‐ratio, lime content, soil moisture, thickness of A‐ and Gr‐horizons) on the basis of 38 soil sample plots (northern Germany, Schleswig‐Holstein) and a principal component analysis. In addition, we tried to explain the species richness of moist forests in the context of the species pool hypothesis by comparing the local species richness with the regional species pool.Taking moist forests as an example our results confirm the findings of other studies that the species richness of basiphilous forest communities is due to the great number of basiphilous species in the Central European forest flora. In deciduous forests in northern Germany in general the species richness increases with increasing base supply. However, particularly in moist forests the species composition/richness is affected mainly by the soil moisture, as this site parameter is responsible for a certain site heterogeneity and niche availability, and therefore often masks the influence of other site factors. The lime content in the subsoil and the base supply are of subordinate importance for the species composition and are little (negatively) or not correlated with the species richness, respectively. Light conditions and the C/N‐ratio have almost no influence on the species richness. The results present evidence in favour of the species pool hypothesis.
Vom Minnesang in der Datenbank
Authors: Schlechter Armin , Zimmermann Karin , Miller Matthias 
Published: December 2003

AbstractDie mittelalterlichen deutschen Handschriften der Universitätsbibliothek Heidelberg sind kulturhistorische Zeugnisse von Rang. Durch umfassende Katalogisierung wird die Sammlung für die Forschung neu erschlossen
Elderly suicide attempters with depression are often diagnosed only after the attempt
Authors: Suominen Kirsi , Isometsä Erkki , Lönnqvist Jouko 
Published: January 2004

AbstractObjectiveNo previous study has comprehensively investigated the pattern of health care contacts among elderly subjects attempting suicide. The present study compared elderly suicide attempters with younger attempters, before and after attempted suicide, in terms of health care contacts, clinical diagnoses of mental disorders, and characteristics predicting lack of treatment contact after the index attempt.MethodsAll consecutive 1198 suicide attempters treated in hospital emergency rooms in Helsinki, Finland, from 15.1.1997 to 14.1.1998 were identified and divided into two age groups: (1) elderly suicide attempters aged 60 years or more (n = 81) and (2) suicide attempters aged under 60 years (n = 1117).ResultsDuring the final 12 months before the attempt, the majority of elderly suicide attempters had a contact with primary health care, but their mood disorders were likely to have remained undiagnosed before the index attempt. In primary health care, only 4% had been diagnosed with a mood disorder before the attempt, but 57% after (p < 0.001). After the suicide attempt, most elderly suicide attempters were referred for aftercare, two thirds having contact with psychiatric care.ConclusionsFor purposes of preventing suicidal behaviour, screening for depression, plus further education on recognition, diagnosis and treatment of mood disorders among the elderly in primary health care setting are needed. Copyright © 2004 John Wiley & Sons, Ltd.
Cross‐national comparison and validation of the Alzheimer's Disease Assessment Scale: results from the European Harmonization Project for Instruments in Dementia (EURO‐HARPID)
Authors: Verhey Frans R. , Houx Peter , van Lang Natascha , Huppert Felicia , Stoppe Gabriella , Saerens Jos , Böhm Peter , de Vreese Luc , Nordlund Arto , DeDeyn Peter P. , Neri Mirco , Peña‐Casanova Jordi , Wallin Anders , Bollen Eduard , Middelkoop Huub , Nargeot Marie‐Christine , Puel Michèle , Fleischmann Ulrich M. , Jolles Jellemer 
Published: January 2004

AbstractBackgroundThe Alzheimer's Disease Assessment Scale (ADAS) is often used in international multicenter trials. Use across countries presupposes correct translation and adaptation of the scale, and maintenance of its psychometric properties.ObjectivesTo compare the various translations of the ADAS used in Western Europe, to design internationally harmonized translations and to validate these.SettingInternational cooperative study in eight European countries.MethodsAn inventory was made of existing versions of the ADAS‐Cog used in eight European countries, and adaptations were made. The concurrent validity of the harmonized versions of the ADAS was tested in 283 patients with probable or possible Alzheimer's disease. The Nurses Observation Scale for Geriatrics (NOSGER), CAMCOG‐R and MMSE was used to assess concordance between cognitive and behavioral measures.ResultsDifferences between the versions mainly involved object naming, items for verbal memory, such as the number of trials allowed, the imagery value of the words selected as targets or distractors, and the number of parallel versions. These differences were eliminated by adapting and harmonizing the various versions of the ADAS‐Cog. Thereafter, only small differences between the different countries were found, and patterns of correlation between ADAS‐Cog, and the NOSGER, CAMCOG‐R and MMSE were consistent.ConclusionsThe study underlines the need to use harmonized versions of instruments for rating dementia in multinational studies. The findings indicate that the harmonization of the ADAS‐Cog was successful. Copyright © 2004 John Wiley & Sons, Ltd.
A multinational, randomised, 12‐week study comparing the effects of donepezil and galantamine in patients with mild to moderate Alzheimer's disease
Authors: Jones Roy W. , Soininen Hilkka , Hager Klaus , Aarsland Dag , Passmore Peter , Murthy Anita , Zhang Richard , Bahra Ranbir 
Published: January 2004

AbstractObjectivesTo compare directly, in the same patient cohort, the ease of use and tolerability of donepezil and galantamine in the treatment of Alzheimer's disease (AD), and investigate the effects of both treatments on cognition and activities of daily living (ADL).MethodsPatients with mild to moderate AD from 14 European centres were randomised to receive open‐label donepezil (up to 10 mg once daily) or galantamine (up to 12 mg twice daily) for 12 weeks, according to the approved product labelling. Physicians and caregivers completed questionnaires rating satisfaction with treatment/ease of use in daily practice. Secondary assessments were the ADAS‐cog, the MMSE, and the DAD scale to assess ADL. Tolerability was evaluated by reporting adverse events (AEs).ResultsBoth physicians and caregivers reported significantly greater overall satisfaction/ease of use for donepezil (n = 64) compared with galantamine (n = 56) at weeks 4, 12, and endpoint (week 12 LOCF; all p‐values <0.05). Significantly greater improvements in cognition were also observed for donepezil versus galantamine on the ADAS‐cog at Week 12 and endpoint (p‐values <0.05). ADL improved significantly in the donepezil group compared with the galantamine group at weeks 4, 12, and endpoint (p‐values <0.05). Most AEs were mild to moderate, however, 46% galantamine‐treated patients reported gastrointestinal AEs vs 25% donepezil patients.ConclusionsPhysician and caregiver ease of use/satisfaction scores, and assessments of cognition and ADL, showed significant benefits for donepezil compared with galantamine in this direct comparative trial. Both treatments were well tolerated, with more gastrointestinal AEs reported for galantamine vs donepezil. Copyright © 2004 John Wiley & Sons, Ltd.
Obesity and depressive symptoms in Chinese elderly
Authors: Bin Li Zhi , Yin Ho Sai , Man Chan Wai , Sang Ho Kin , Pik Li Mun , Leung Gabriel M , Hing Lam Tai 
Published: January 2004

AbstractObjectivesThe main objective was to examine the association between obesity and depressive symptoms among Chinese elderly in Hong Kong.MethodsCross‐sectional data on depressive symptoms and body mass index from 56 167 clients aged 65 or over who enrolled as members of Elderly Health Centres from July 1998 to December 2000 were analysed using multiple logistic regression with adjustment of potential confounders.ResultsAmong 18 750 men and 37 417 women, the prevalence [95% confidence interval (CI)] of depressive symptoms (based on the Geriatric Depression Scale) was 4.9% (4.6–5.2%) and 7.9% (7.6–8.1%) respectively (p < 0.001). The prevalence of obesity (by World Health Organisation Asian standard: body mass index ≥25.0) in women was significantly higher than that of men (42.1% (41.6–42.7%) vs 36.6% (35.9–37.3%), p < 0.001). Obese men and women were about 20% less likely to suffer from depressive symptoms compared with those with normal weight after adjustment for confounders, with odds ratios (95% CI) of 0.82 (0.69–0.97) and 0.78 (0.71–0.86) respectively. Negative linear trends were observed between depressive symptoms and BMI categories in both sexes, and women showed a greater slope and stronger statistical significance than men.ConclusionsBoth obese elderly men and women in Hong Kong were less likely to suffer from depressive symptoms than those of normal weight. The results support the ‘jolly fat’ hypothesis previously restricted to men, and extend the hypothesis to female elderly. Chinese traditional culture and positive values towards obesity may be protective against depressive symptoms. Copyright © 2004 John Wiley & Sons, Ltd.
Validity of the Telephone Interview for Cognitive Status (TICS) in post‐stroke subjects
Authors: Barber Mark , Stott David J. 
Published: January 2004

AbstractBackgroundCognitive impairment and dementia are very common after stroke. Telephone screening has potential advantages for clinical follow‐up and population‐based research in this group. We wished to test the validity of the Telephone Interview for Cognitive Status (TICS) for cognitive testing in post‐stroke subjects.MethodsCognitive function in stroke outpatients was assessed using the R‐CAMCOG (a modification of the cognitive part of the Cambridge Examination for Mental Disorders of the Elderly, for use in stroke subjects) along with the TICS and a modified version, the TICSm. The tests were administered in random order. A cut‐off point of 33 on the R‐CAMCOG was used to define post‐stroke dementia.ResultsSixty‐four patients with a median age of 72 years were assessed. The Pearson correlation coefficients between the R‐CAMCOG and the TICS and TICSm were 0.833 and 0.855 (both p <0.001) respectively. Twenty‐four (38%) patients met R‐CAMCOG criteria for post‐stroke dementia. The area under the ROC curve for both the TICS and TICSm was 0.94. Using a cut‐off of 28 or less on the TICS produced a sensitivity of 88% and a specificity of 85% for the diagnosis of post‐stroke dementia. For the TICSm a cut‐off of 20 or lower produced a sensitivity of 92% and a specificity of 80%.ConclusionsThe TICS and TICSm telephone questionnaires are practicable and valid methods of assessing cognitive function in community outpatients following stroke. Scores of ≤28 and ≤20 respectively carry good sensitivity and specificity for the diagnosis of post‐stroke dementia. Copyright © 2004 John Wiley & Sons, Ltd.
Syntheses and biological activities of S‐1,2,4‐triazolo(1,5‐a)pyrimidinylalkyl dithiophosphates
Authors: Chen Wen‐Bin , Jin Gui‐Yu 
Published: January 2004

AbstractWe introduced dithiophosphate moieties into the fused heterocyclic compound to prepare the title derivatives and characterized their structures by elemental analysis, 1H NMR, and IR spectral data. We found that these compounds show good fungicidal and herbicidal activities and good plant growth regulation activity. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:607–611, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10198
Pyridazine, oxazine, pyrrole, and pyrrolo[1,2‐a]quinazoline derivatives from malononitrile dimer
Authors: Eldin Abdellatif M. Salah 
Published: January 2004

Abstract2‐Amino‐1,1,3‐tricyano‐3‐bromopropene was obtained from bromination of 2‐amino‐1,1,3‐tricyanopropene (malononitrile dimer) with N‐bromosuccinimide. This bromo derivative reacts with hydrazine hydrate, phenyl hydrazine, and hydroxylamine hydrochloride to afford pyridazine and oxazine derivatives, respectively. In base‐catalyzed reactions with primary aromatic amines and anthranilic acid derivatives, it produces N‐aryl pyrrol‐3,5‐dicarbonitrile and pyrrolo[1,2‐a]quinazolin‐5‐imine, or pyrrolo[1,2‐a]quinazolin‐5‐one derivatives, respectively. The structures of the newly synthesized heterocycles were established on the basis of elemental analyses and spectral data. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:612–616, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10199
A convenient synthesis of diacyl sulfides using a novel sulfur transfer reagent
Authors: Koketsu Mamoru , Sekiya Yoji , Ishihara Hideharu 
Published: January 2004

AbstractVarious diacyl sulfides were synthesized by reaction of acyl chlorides with LiAlHSH. Reaction of glutaryl chloride with LiAlHSH afforded glutaric thioanhydride. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:633–635, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10217
Indole‐Diterpene Synthetic Studies: Total Synthesis of (−)‐21‐Isopentenylpaxilline
Authors: Smith Amos B. , Cui Haifeng 
Published: December 2003

AbstractAn efficient, stereocontrolled total synthesis of the complex indole‐diterpene alkaloid (−)‐21‐isopentenylpaxilline (1) has been achieved. Key elements of the synthesis include the stereocontrolled construction of the advanced eastern hemisphere (−)‐68, involving a highly efficient union of the eastern and western fragments (−)‐68 and 5 exploiting our 2‐substituted indole synthesis, application of the Negishi π cycloalkylation tactic as a new, potentially general protocol for the construction of ring C, and the fragmentation of a β,γ‐epoxy ketone to introduce the tertiary OH group at C(13) in the indole diterpene skeleton.
Mechanism and Control in Biological Amine Methylation
Authors: Blackburn G. Michael , Gamblin Steven J. , Wilson Jonathan R. 
Published: December 2003

AbstractBiological methylation is a subject that has fascinated mechanistically minded chemists for over 50 years. While early studies were usually directed at C‐methylation in natural products, more recent work on N‐methylation in DNA and proteins is being supported by the results of X‐ray crystallography. From this source, significant mechanistic detail can be gleaned and powerful insights gained into the nature of enzyme catalysis and selectivity in methyl‐transfer processes. The case of the human histone H3 transmethylase SET7/9 is considered in detail and compared to cognate histone lysine methylases. It provides an analysis of Nature's solution to the task of avoiding over‐methylation.
On the Formation of 2‐Sulfonylbenzo[a]heptalene‐1,3‐diols as Precursors for the Synthesis of Colchicinoids
Authors: Abou‐Hadeed Khaled , Hansen Hans‐Jürgen 
Published: December 2003

AbstractThe benzo[a]heptalene formation from 4‐[(R‐sulfonyl)acetyl]heptalene‐5‐carboxylates 15 and 5‐[(R‐sulfonyl)acetyl]heptalene‐4‐carboxylates 16 (R=Ph or morpholino) in the presence of R′SO2CH2Li and BuLi has been investigated (Scheme 6). Only the sulfonyl moiety linked to the CO group at C(4) of the heptalene skeleton is found at C(3) of the formed benzo[a]heptalene‐2,4‐diols 3 in accordance with the general mechanism of their formation (Scheme 3). Intermediates that might rearrange to corresponding 2‐sulfonylbenzo[a]heptalene‐1,3‐diols lose HO− under the reaction conditions to yield the corresponding cyclopenta[d]heptalenones of type 11 (Schemes 6 and 7). However, the presence of an additional Me group at C(α) of the lithioalkyl sulfones suppresses the loss of HO−, and 4‐methyl‐2‐sulfonylbenzo[a]heptalene‐1,3‐diols of type 4c have been isolated and characterized for the first time (Schemes 8 and 10). A number of X‐ray crystal‐structure analyses of starting materials and of the new benzo[a]heptalenes have been performed. Finally, benzo[a]heptalene 4c has been transformed into its 1,2,3‐trimethoxy derivative 23, a benzo[a]heptalene with the colchicinoid substitution pattern at ring A (Scheme 11).
Parity‐Violating Potentials for the Torsional Motion of Methanol (CH3OH) and Its Isotopomers (CD3OH, 13CH3OH, CH3OD, CH3OT, CHD2OH, and CHDTOH)
Authors: Berger Robert , Quack Martin , Sieben Achim , Willeke Martin 
Published: December 2003

AbstractWe present calculations on the parity‐conserving and the parity‐violating potentials in several MeOH isotopomers for the torsional motion by the newly developed methods of electroweak quantum chemistry from our group. The absolute magnitudes of the parity‐violating potentials for MeOH are small compared to H2O2 and C2H4, but similar to C2H6, which is explained by the high (threefold) symmetry of the torsional top in MeOH and C2H6. ‘Chiral’ and ‘achiral’ isotopic substitutions in MeOH lead to small changes only, but vibrational averaging is discussed to be important in all these cases. Simple isotopic sum rules are derived to explain and predict the relationships between parity‐violating potentials in various conformations and configurations of the several isotopomers investigated. The parity‐violating energy difference ΔpvE=Epv(R)−Epv(S) between the enantiomers of chiral CHDTOH, first synthesized by Arigoni and co‐workers, is for two conformers ca. −3.66⋅10−17 and for the third one +7.32⋅10−17 hc cm−1. Thus, for ΔpvE, the conformation is more important than the configuration (at the equilibrium geometries, without vibrational averaging). Averaging over torsional tunneling may lead to further cancellation and even smaller values.
Preparation of (S,S)‐Fmoc‐β2hIle‐OH, (S)‐Fmoc‐β2hMet‐OH, and (S)‐Fmoc‐β2hTyr(tBu)‐OH for Solid‐Phase Syntheses of β2‐ and β2/β3‐Peptides
Authors: Sebesta Radovan , Seebach Dieter 
Published: December 2003

AbstractThe preparation of three new N‐Fmoc‐protected (Fmoc=[(9H‐fluoren‐9‐yl)methoxy]carbonyl) β2‐homoamino acids with proteinogenic side chains (from Ile, Tyr, and Met) is described, the key step being a diastereoselective amidomethylation of the corresponding Ti‐enolates of 3‐acyl‐4‐isopropyl‐5,5‐diphenyloxazolidin‐2‐ones with CbzNHCH2OMe/TiCl4 (Cbz=(benzyloxy)carbonyl) in yields of 60–70% and with diastereoselectivities of >90%. Removal of the chiral auxiliary with LiOH or NaOH gives the N‐Cbz‐protected β‐amino acids, which were subjected to an N‐Cbz/N‐Fmoc (Fmoc=[(9H‐fluoren‐9‐yl)methoxy]carbonyl) protective‐group exchange. The method is suitable for large‐scale preparation of Fmoc‐β2hXaa‐OH for solid‐phase syntheses of β‐peptides. The Fmoc‐amino acids and all compounds leading to them have been fully characterized by melting points, optical rotations, IR, 1H‐ and 13C‐NMR, and mass spectra, as well as by elemental analyses.
Synthesis of a Derivative of the Peptaibol‐Antibiotic Trichovirin I 1B by Means of the ‘Azirine/Oxazolone Method’
Authors: Luykx Roeland T. N. , Linden Anthony , Heimgartner Heinz 
Published: December 2003

AbstractAccording to the earlier published synthesis of the C‐terminal nonapeptide of Trichovirin I 1B, Z‐Ser(tBu)‐Val‐Aib‐Pro‐Aib‐Leu‐Aib‐Pro‐Leuol (5), the complete tetradecapeptide Z‐Aib‐Asn(Trt)‐Leu‐Aib‐Pro‐Ser(tBu)‐Val‐Aib‐Pro‐Aib‐Leu‐Aib‐Pro‐Leuol (11b), a protected Trichovirin I 1B, has now been prepared by means of the ‘azirine/oxazolone method’. With the exception of the N‐terminal Aib(1), all Aib residues were introduced by the coupling of the corresponding amino or peptide acids with 2,2‐dimethyl‐2H‐azirine‐3‐(N‐methyl‐N‐phenylamine) (1a) and methyl N‐(2,2‐dimethyl‐2H‐azirin‐3‐yl)‐L‐prolinate (3a) as the Aib and Aib‐Pro synthons, respectively. Single crystals of two segments, i.e., the N‐terminal hexapeptide Z‐Aib‐Asn(Trt)‐Leu‐Aib‐Pro‐Ser(tBu)‐OMe (23) and the C‐terminal octapeptide Z‐Val‐Aib‐Pro‐Aib‐Leu‐Aib‐Pro‐Leuol (17), were obtained and their structures have been established by X‐ray crystallography. Following the same strategy, the C‐terminal nonapeptide of Trichovirin I 4A, Z‐Ala‐Val‐Aib‐Pro‐Aib‐Leu‐Aib‐Pro‐Leuol (26), was also synthesized and characterized by X‐ray crystallography.
Outlying Charge, Stability, Efficiency, and Algorithmic Enhancements in the Quantum‐Mechanical Solvation Method, COSab‐GAMESS
Authors: Gregerson Laura N. , Baldridge Kim K. 
Published: December 2003

AbstractIn this work, we present algorithmic modifications and extensions to our quantum‐mechanical approach for the inclusion of solvent effects by means of molecule‐shaped cavities. The theory of conductor‐like screening, modified and extended for quantum‐mechanical techniques, serves as the basis for our solvation methodology. The modified method is being referred to as COSab‐GAMESS and is available within the GAMESS package. Our previous work has emphasized the implementation of this model by way of a distributed multipole approach for handling the effects of outlying charge. The method has been enabled within the framework of open‐ and closed‐shell RHF and MP2. In the present work, we present a) a second method to handle outlying charge effects, b) algorithmic extensions to open‐ and closed‐shell density‐functional theory, second‐derivative analysis, and reaction‐path following, and c) enhancements to improve performance, convergence, and predictability. The method is now surtable for large molecular systems. New features of the enhanced continuum model are highlighted by means of a set of neutral and charged species. Computations on a series of structures with roughly the same molecular shape and volume provides an evaluation of cavitation effects.