bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protonierte fluorenon‐ionen aus N.N‐diarylsubstituierten 1.4‐diazaspiro[4.4]nonanen: Eine neue elektronenstossinduzierte arylwanderung
Authors: Schwarz H. , Schönberg A. , Singer E. , Rapp U. , Kaufmann H. , Meier S. 
Published: April 2009

AbstractUsing collisional activation mass spectrometry (CA) and suitable reference ions it can be shown that the title compounds rearrange to protonated fluorene ions. The mechanism of this novel aryl migration as well as possible alternative ion structures are discussed.
Nucleosides CIII. Anhydropyrimidine‐C‐nueleosides. Synthesis of 4,2′‐anhydro‐5‐(β‐D‐arabinofuranosyl)‐ and 5‐(β‐D‐arabinofuranosyl)pyrimidine C‐nucleosides
Authors: Reichman U. , Chu C. K. , Wempen I. , Watanabe K. A. , Fox J. J. 
Published: April 2009

Abstract4,2′‐Anhydro‐5‐(β‐D‐arabinofuranosyl)isocytosine and 4,2′‐anhydro‐5‐(β‐D‐arabinofuranosyl)‐uracil were synthesized. Treatment of Ψ‐isocytidine with either α‐acetoxyisobutyryl chloride or salicyloyl chloride in acetonitrile afforded the acylated anhydronucleoside. Deacylation of the product with methanol‐hydrogen chloride afforded 4,2′‐anhydro‐5‐(β‐D‐arabinofuranosyl)isocylosine hydrochloride in crystalline form. Analogous reaction of Ψ‐uridine with the acyl chloride reagents, however, always gave a mixture of the acylated anhydronucleoside and 2′‐chloro‐2′‐deoxy‐Ψ‐uridine. Treatment of these products either singly or as a mixture with sodium methoxide in methanol afforded 4,2′‐anhydro‐5‐(β‐D‐arabinofuranosyl)uracil in crystalline form in good yield.5‐(β‐D‐Arabinofuranosyl)isocytosine was obtained upon treatment of the corresponding 4,2′‐anhydronucleoside with 10% sodium hydroxide under reflux for 30 minutes. Treatment of the anhydro uracil nucleoside with a small amount of Dowex 50(H+) in water at 50° gave 5‐(β‐D‐arabinofuranosyl)uracil.
Synthesis of oxetanes by photoaddition of carbonyl compounds to pyrrole derivatives
Authors: Rivas C. , Bolívar R. A. 
Published: April 2009

AbstractSeveral electron attracting groups have been substituted on the nitrogen atom to decrease the electron density of the pyrrole ring in order to make it more suitable for photoaddition reactions. Once it was found that N‐benzoylpyrrole is the only compound of the series studied, capable of undergoing oxetane formation, other carbonyl compounds in addition to benzophenone were tested as possible addends to the ring. Successful additions were observed when 3‐ and 4‐benzoyl‐pyridine were used.
Heterocycles from ylides. Part V (1). Reactivity of 4‐arylmethylene‐Δ2 ‐isoxazolin‐5‐ones with stabilized sulfur ylides
Authors: Dalla Croce Piero 
Published: April 2009

Abstract4‐Arylmethylene‐Δ2 ‐isoxazolin‐5‐ones react with carbonyl‐stabilized sulfur ylides yielding spiro[cyclopropane‐1,4′‐Δ2‐isoxazolin]‐5′‐ones identified from spectroscopic data and chemical behaviour.
Effects of various cover crops after peas on nitrate leaching and nitrogen supply to succeeding winter wheat or potato crops
Authors: Möller Kurt , Reents Hans‐Jürgen 
Published: April 2009

AbstractIn organic farming systems, it has been demonstrated that grain pulses such as peas often do not enhance soil N supply to the following crops. This may be due to large N removals via harvested grains as well as N‐leaching losses during winter. In two field‐trial series, the effects of legume (common vetch, hairy vetch, peas) and nonlegume (oil radish) cover crops (CC), and mixtures of both, sown after peas, on soil nitrate content, N uptake, and yield of following potatoes or winter wheat were studied. The overall objective of these experiments was to obtain detailed information on how to influence N availability after main‐crop peas by adapting cover‐cropping strategies. Cover crops accumulated 56 to 108 kg N ha–1 in aboveground biomass, and legume CC fixed 30–70 kg N ha–1 by N2 fixation, depending on the soil N supply and the length of the growing period of the CC. Nitrogen concentration in the aboveground biomass of legume CC was much higher and the C : N ratio much lower than in the nonlegume oil radish CC. At the time of CC incorporation (wheat series) as well as at the end of the growing season (potato series), soil nitrate content did not differ between the nonlegume CC species and mixtures, whereas pure stands of legume CC showed slightly increased soil nitrate content. When the CC were incorporated in autumn (beginning of October) nitrate leaching increased, especially from leguminous CC. However, most of the N leached only into soil layers down to 1.50 m and was recovered more or less by the following winter wheat. When CC were incorporated in late winter (February) no increase in nitrate leaching was observed. In spring, N availability for winter wheat or potatoes was much greater after legumes and, after mixtures containing legumes, resulting in significantly higher N uptake and yields in both crops. In conclusion, autumn‐incorporated CC mixtures of legumes and nonlegumes accomplished both: reduced nitrate leaching and larger N availability to the succeeding crop. When the CC were incorporated in winter and a spring‐sown main crop followed even pure stands of legume CC were able to achieve both goals.
Comparison of two procedures for particle‐size analysis: Köhn pipette and X‐ray granulometry
Authors: Müller Hans‐Werner , Dohrmann Reiner , Klosa Detlef , Rehder Sönke , Eckelmann Wolf 
Published: April 2009

AbstractKnowledge on particle‐size distribution (PSD) is crucial to the classification and description of soils and sediments. Since the early 1900s, various methods of PSD analysis have been in use. In Germany, analysis of PSD is conducted according to DIN ISO 11277:2002‐08. This procedure involves a combination of sieving (particles 63 μm to 2000 μm) and sedimentation (particles <63 μm). Köhn pipette is the standard procedure for sedimentation. It is still conducted manually and is very time‐consuming. As an automated alternative method, X‐ray granulometry (XRG) was tested using the SediGraph 5100™ particle‐size analyzer. With this device, the gravity‐induced settling rates of different‐size particles can be measured. The method is based on the same principles used in Köhn pipette (Stokes' law). However, work is carried out through X‐ray absorption of particles in a suspension instead of pipetting and weighing.For this study, both methods were applied to approx. 500 samples from various locations in Germany. Care was taken in making sure these samples are representative of important patterns of particle‐size distribution in soils of Central Europe. Based on statistical methods of calculation, nonlinear regression functions became apparent. Therefore, XRG data can be recalculated into approximate data potentially derived from an analysis per Köhn pipette with an acceptable degree of accuracy and precision. Usually, use of XRG generates slightly higher clay contents. Currently, automated Köhn pipette devices with greater measuring capacities are in use. This eliminates the disadvantages posed by manual operation.
Biostimulant activity of two protein hydrolyzates in the growth and nitrogen metabolism of maize seedlings
Authors: Ertani Andrea , Cavani Luciano , Pizzeghello Diego , Brandellero Elena , Altissimo Adriano , Ciavatta Claudio , Nardi Serenella 
Published: April 2009

AbstractTwo protein hydrolyzate–based fertilizers (PHFs), one from alfalfa (AH) and one from meat flour (MFH), were studied chemically and biologically. AH and MFH revealed a different degree of hydrolysis and a different amino acid composition. The biostimulant activity was investigated using two specific and sensitive bioassays of auxins and gibberellins. Extracts of AH and MFH elicited a gibberellin‐like activity and a weak auxin‐like one. To improve our understanding of the biostimulant activity, AH and MFH were supplied to maize plants and their effect on growth and nitrate metabolism was studied. Both PHFs increased root and leaf growth and induced morphological changes in root architecture. Besides, the treatments increased nitrate reductase (NR) and glutamine synthetase (GS) activities, suggesting a positive role of the two hydrolyzates in the induction of nitrate conversion into organic nitrogen. Moreover, treatments enhanced GS1 and GS2 isoforms in maize leaves. The latter isoform, amounting to 5‐ to 7‐fold the level of the former, appears to be a superior form in the assimilation of ammonia. The high NR and GS activities together with the high induction of GS isoforms indicate a stimulatory effect of the two PHFs on the assimilation of nitrate. In addition, a role of amino acids and small peptides of the two PHFs is suggested in the regulation of the hormone‐like activity and nitrogen pathway.
Chemical structure of phosphazenes in relation to the tribological properties of a steel‐on‐steel system
Authors: Zhu Jiamei , Chu Ruizhi , Meng Xianliang 
Published: April 2009

AbstractThe tribological behaviours of a steel‐on‐steel contact lubricated by three different fluids: (i) tetrakis(3‐trifluoromethylphenoxy)‐bis(4‐fluorophenoxy)‐cyclotriphosphazene (X‐1P), (ii) a synthetic bridged cyclotriphosphazene, and (iii) linear phosphazene derivative as base fluids were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The results show that X‐1P records the lowest friction coefficient, and linear phosphazene oligomer gives the lowest wear volume loss of the steel among the investigated lubricants. Moreover, the bridged cyclotriphosphazene shows much better anti‐wear ability than cyclotriphosphazene (X‐1P) at both room and elevated temperatures. The worn surfaces were analysed by means of scanning electron microscopy, energy dispersive spectrometry and X‐ray photoelectron spectroscopy. The results demonstrate that the protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic F‐containing compounds; nitrogen oxide and FeF2 played an important role in improving the friction and wear behavior of the steel‐on‐steel system. Copyright © 2009 John Wiley & Sons, Ltd.
Die Prozessindustrie trifft sich
Authors: Bulmahn Maren 
Published: April 2009

AbstractDie Aussteller haben zur Achema viel Neues angekündigt, sie werden zudem Bewährtes zeigen und scheinen von der Wirtschaftskrise unbeeindruckt. Dazu gibt es Vorträge zu Themen von Biotechnik bis Hochschule sowie Foren für Mitarbeiter‐ und Stellungsuchende und für Wirtschaftsfachleute.
”Auch ein Kamel hat Zornausbrüche“
Authors: Guggolz Ernst , Schami Rafik , Fadel Suheil 
Published: April 2009

AbstractRafik Schami studierte in Damaskus und Heidelberg Chemie. Seine erste Leidenschaft, das Schreiben und Erzählen, hat er bald darauf zu seinem Beruf gemacht. Die Nachrichten aus der Chemie sprachen mit dem weltweit erfolgreichen Autor übers Studieren, Kochen, Schreiben, über Jugend forscht, E‐Books, Friedrich Schiller, die Phantasie und die Bedeutung seines Studiums für die literarische Arbeit.
Vom Chemiebaukasten in der Zelle zum Krebsmedikament
Authors: Groß Michael 
Published: April 2009

AbstractDie Enzyme der Cytochrom‐P450‐Familie katalysieren Oxidationsreaktionen. Ein Enzym, die Aromatase, ist bei hormonabhängigen Krebserkrankungen aktiv. Die Kenntnis der Kristallstruktur der menschlichen Aromatase nützt deshalb Medikamentenentwicklern.
Die Mitglieder hatten das Wort
Authors: Karger Gerhard 
Published: April 2009

Abstract”Eher zufrieden“ sind die Mitglieder der GDCh mit ihrer Fachgesellschaft, und ”eher stark“ fühlen sie sich mit ihr verbunden. Das Resultat der Online‐Mitgliederumfrage der GDCh vom vergangenen Herbst positioniert die GDCh mit ihren Leistungen im Idealbereich und zeigt, dass die GDCh darüber hinaus vieles, aber noch nicht alles richtig macht.
A metric study of three types of artificial cranial modification from north‐central Peru
Authors: Pomeroy Emma , Stock Jay T. , Zakrzewski Sonia R. , Lahr Marta Mirazón 
Published: April 2009

AbstractArtificial cranial modification (ACM) involves the alteration of cranial vault shape by cultural means, and is performed during infancy while the cranial bones remain soft and malleable. The direction of normal cranial growth is altered through the application of external forces. In this study, three types of ACM from north‐central Peru (posterior flattening, bilobed and circumferential) were analysed using standard craniometric techniques. The aim was to determine the effects of these forms of ACM on craniofacial morphology, and the extent to which different types of ACM could be distinguished from one another and unmodified crania on the basis of these measurements. Significant differences between artificially modified and unmodified crania, and between different types of ACM, were demonstrated in cranial vault shape for all types. Significant differences in facial morphology were found only in the bilobed group compared with the unmodified crania. Canonical variates analysis (discriminant analysis) confirmed that major differences between modification types and unmodified crania were in measurements and angles of the cranial vault. While the results show some similarities to previous studies, they add to the variability in the patterns and extent of differences documented to date. It is suggested, based on these results and visual observations, that interpopulation variation in ACM within major modification categories may explain some of the variability in results between studies, an explanation which has previously received insufficient recognition but which remains to be tested since varied methodology between studies may also be a contributory factor. While previous studies have often sought to generalise about the effects of ACM, the examination of the differences between populations even within major ACM categories may offer new insight into cultural variation in modification techniques between populations and the nature of craniofacial development. Copyright © 2009 John Wiley & Sons, Ltd.
Health status at long‐term follow‐up in patients treated for extremity localized Ewing Sarcoma or osteosarcoma: A Scandinavian sarcoma group study
Authors: Aksnes L.H. , Bauer H.C.F. , Dahl A.A. , Fosså S.D. , Hjorth L. , Jebsen N. , Lernedal H. , Hall K. Sundby 
Published: April 2009

AbstractBackgroundThe purpose of this study was to evaluate late effects and symptom complaints in long‐term survivors (>5 years) of Extremity Bone Sarcoma (EBS survivors). The results were compared with findings in age‐ and gender‐matched individuals from the general population (NORMs).Patients and MethodsAmong 155 EBS survivors approached, 133 (86%) were included, and 110 of them (83%) attended an outpatient examination. Health status was evaluated by a mailed questionnaire concerning demographic and current health issues, and physical examinations at the outpatient clinic. Age‐ and gender‐adjusted normative controls were drawn from participants of the Health Study of Nord‐Trøndelag County (HUNT 2).ResultsMedian age at follow‐up was 29 (15–57) years. Median follow‐up was 12 (6–22) years. Of EBS survivors 42% had ≥1 somatic disease, 33% had ototoxicity and 13% had reduced renal function. EBS survivors were more likely to have heart disease (odds ratio [OR], 7.9; 95% confidence interval [95% CI], 2.5–25.3; P = 0.001), hypertension (OR, 3.4; 95% CI, 1.1–10.1; P = 0.03) and thyroid disease (OR, 3.0; 95% CI, 1.1–8.3; P = 0.04) compared to NORMs. EBS survivors reported more diarrhoea (29% vs. 19%, P = 0.02), palpitations (23% vs. 13%, P = 0.01) and shortness of breath (11% vs. 5%, P = 0.01) than NORMs.ConclusionsEBS survivors have poorer health status compared to age‐ and gender‐matched controls. Long‐term follow‐up of these patients is therefore mandatory. Pediatr Blood Cancer 2009;53:84–89. © 2009 Wiley‐Liss, Inc.
Comprehensive analysis of the Brassica juncea root proteome in response to cadmium exposure by complementary proteomic approaches
Authors: Alvarez Sophie , Berla Bertram M. , Sheffield Jeanne , Cahoon Rebecca E. , Jez Joseph M. , Hicks Leslie M. 
Published: April 2009

AbstractIndian mustard (Brassica juncea L.) is known to both accumulate and tolerate high levels of heavy metals from polluted soils. To gain a comprehensive understanding of the effect of cadmium (Cd) treatment on B. juncea roots, two quantitative proteomics approaches – fluorescence two‐dimensional difference gel electrophoresis (2‐D DIGE) and multiplexed isobaric tagging technology (iTRAQ) – were implemented. Several proteins involved in sulfur assimilation, redox homeostasis, and xenobiotic detoxification were found to be up‐regulated. Multiple proteins involved in protein synthesis and processing were down‐regulated. While the two proteomics approaches identified different sets of proteins, the proteins identified in both datasets are involved in similar biological processes. We show that 2‐D DIGE and iTRAQ results are complementary, that the data obtained independently using the two techniques validate one another, and that the quality of iTRAQ results depends on both the number of biological replicates and the number of sample injections. This study determined the involvement of enzymes such as peptide methionine sulfoxide reductase and 2‐nitropropane dioxygenase in alternatives redox‐regulation mechanisms, as well as O‐acetylserine sulfhydrylase, glutathione‐S‐transferase and glutathione‐conjugate membrane transporter, as essential players in the Cd hyperaccumation and tolerance of B. juncea.
The algal metabolite yessotoxin affects heterogeneous nuclear ribonucleoproteins in HepG2 cells
Authors: Young Clifford , Truman Penelope , Boucher Magalie , Keyzers Robert A. , Northcote Peter , Jordan T. William 
Published: April 2009

AbstractThe dinoflagellate metabolite yessotoxin (YTX) is produced by several species of algae and accumulates in marine food chains, leading to concerns about possible affects on aquaculture industries and human health. In mice used for toxicity testing, YTX is lethal by the intraperitoneal route, but is considerably less toxic when orally administered. The mode of action of YTX and its potential effect on humans is unclear and we therefore conducted the first proteomic analysis of the effects of this compound. We used 2‐DE to examine protein changes in HepG2 cell cultures exposed to 1.4 μM YTX for 3, 12.5, 18 and 24 h. After selecting proteins that changed more than three‐fold after YTX exposure, 55 spots were deemed significantly affected by the toxin (p<0.05). Major groups of affected proteins include members from the heterogeneous nuclear ribonucleoprotein (hnRNP), lamin, cathepsin and heat shock protein families that often are associated with apoptosis. We therefore confirmed apoptosis using Annexin‐V‐FLUOS staining of phosphatidylserine exposed at the surface of apoptotic cells. Ingenuity pathways analysis also indicated effects on pathways involved in protein processing, cell cycling and cell death.
Anatomic site‐specific proteomic signatures of gastrointestinal stromal tumors
Authors: Suehara Yoshiyuki , Kikuta Kazutaka , Nakayama Robert , Fujii Kiyonaga , Ichikawa Hitoshi , Shibata Tatsuhiro , Seki Kunihiko , Hasegawa Tadashi , Gotoh Masahiro , Tochigi Naobumi , Shimoda Tadakazu , Shimada Yasuhiro , Sano Takeshi , Beppu Yasuo , Kurosawa Hisashi , Hirohashi Setsuo , Kawai Akira , Kondo Tadashi 
Published: April 2009

AbstractThe gastrointestinal stromal tumor (GIST) is the most common mesenchymal malignancy of the gastrointestinal tract. Its clinical course ranges widely from a curable disorder to a highly malignant disease. Although its clinical and molecular characteristics depend on the anatomic site of origin, the molecular background of GIST arising in different anatomical site has not been studied yet. To investigate the proteomic background of GIST, we examined the proteomic features corresponding to the anatomic site of tumor origin. Comparison of the proteomic profile of gastric (23 cases) and small intestinal (9 cases) GIST by 2‐DE revealed 105 protein spots with significantly different intensity (p <0.01) between the two groups. Mass spectrometric study identified 68 distinct proteins for these 105 protein spots, including cancer‐associated ones such as prohibitin, pigment epithelium‐derived factor, and alpha‐actinin 4. The intensity of 37/105 (35.2%) protein spots was significantly concordant with the corresponding mRNA levels (p <0.01). Although both 2‐D DIGE and microarray experiments showed significant up‐regulation of vimentin expression in small intestinal GIST, Western blotting did not show a significant difference between the two groups. In conclusion, our study demonstrates the proteins specially expressed in GIST depending on their site of origin, as well as the unique advantage offered by use of proteomics to acquire such data. The identified proteins may provide clues to understanding the different characteristics of GIST depending on their site of origin.
Automatic extraction of proximal femur contours from calibrated X‐ray images using 3D statistical models: anin vitrostudy
Authors: Dong Xiao , Zheng Guoyan 
Published: April 2009

AbstractBackgroundAccurate extraction of bone contours from two‐dimensional (2D) projective X‐ray images is an important component for computer‐assisted diagnosis, planning or three‐dimensional (3D) reconstruction.MethodsWe propose a 3D statistical model‐based, fully automatic segmentation framework for extracting the proximal femur contours from calibrated X‐ray images. The automatic initialization is an estimation of a Bayesian network algorithm to fit a multiple‐component geometrical model to the X‐ray data. The contour extraction is accomplished by a non‐rigid 2D/3D registration between the statistical model and the X‐ray images, in which bone contours are extracted by a graphical model‐based Bayesian inference.ResultsThe contour extraction algorithm was verified on both cadaver and clinical datasets, visually and quantitatively. Compared to the ‘gold standard’, a mean error of 1.6 mm was observed when the automatically extracted contours were used to reconstruct a patient‐specific surface model.ConclusionsOur statistical model‐based bone contour extraction approach holds the potential to facilitate the application of 2D/3D reconstruction in surgical navigation. Copyright © 2009 John Wiley & Sons, Ltd.
Artesunate induced morphological and mechanical changes of Jurkat cell studied by AFM
Authors: Cai Xiaofang , Gao Shijun , Cai Jiye , Wu Yangzhe , Deng Hua 
Published: April 2009

AbstractIn this study, we have used atomic force microscopy (AFM) to study the morphology and mechanical property changes of Jurkat cells exposed to different concentrations of Artesunate (ART) for 24 h at single cellular level. Cell viability and proliferation assays were performed by using the Cell Counting Kit‐8. The concentration of ART, which resulted in the inhibition rate >50% was selected. The AFM images revealed that the cell membrane changed and the ultrastructure also became complex. Mechanical properties of individual cell were tracked with AFM‐based force spectroscopy. The force curves revealed that when a cell was exposed to the ART, the mechanical properties changed obviously. Treated cells had a lower adhesion force of 416.8±37.9 pN, whereas control group had a higher adhesion force of 1064.2±97.0 pN. The Young's modulus decreased to nearly one‐third, from control group of 0.648±0.037 kPa to treated group of 0.254±0.035 kPa and the stiffness increased to nearly 1.5 times, from control group of 1.231±0.084 mN/m to treated group of 1.917±0.137 mN/m. These results suggest that ART can inhibit the proliferation of Jurkat and induce changes in the morphological structure and mechanical properties of Jurkat cells. The high resolution and high sensitivity of AFM can be used to detect morphological and mechanical properties of cells exposed to ART. The AFM may be developed to be a useful tool for detecting the cell death and evaluating the anti‐carcinogen efficacy against tumor cell. SCANNING 31: 83–89, 2009. © 2009 Wiley Periodicals, Inc.