bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self Metathesis of Fatty Alcohols and Amines to Provide Monomers for Polyester and Polyamide Products
Authors: Riepl Herbert Matthias , Pettrak Jürgen , Faulstich Martin , Herrmann Wolfgang Anton 
Published: July 2010

AbstractSummary: Self metathesis of oleochemicals offers a variety of bifunctional compounds, that can be used as monomer for polymer production. Many precursors are in huge scales available, like oleic acid ester (biodiesel), oleyl alcohol (tensides), oleyl amines (tensides, lubricants). We show several ways to produce and separate and purify C18‐α,ω‐bifunctional compounds, using Grubbs 2nd Generation catalysts, starting from technical grade educts.
Latent Olefin Metathesis Catalysts for Polymerization of DCPD
Authors: Drozdzak Renata , Nishioka Naoki , Recher Gilles , Verpoort Francis 
Published: July 2010

AbstractSummary: Advances in design of latent ruthenium phenylindenylidene catalysts bearing salicylaldimine ligands for ring‐opening metathesis polymerization are described. The presence of the substituents in ortho position in N‐aryl ring of salicylaldimine ligand has been found to be the main factor determining the catalyst stability. The best of the studied catalysts after acid activation offers activity comparable to that of the dichloride systems in ring‐opening metathesis polymerization of DCPD, while maintaining very high stability in the monomer solution.
GIAO, DFT, AIM and NBO analysis of the NH···O intramolecular hydrogen‐bond influence on the1J(N,H) coupling constant in push–pull diaminoenones
Authors: Afonin Andrei V. , Ushakov Igor A. , Vashchenko Alexander V. , Kondrashov Evgeniy V. , Rulev Alexander Yu. 
Published: July 2010

AbstractIn the series of diaminoenones, large high‐frequency shifts of the1H NMR of the NH group in thecis‐position relative to the carbonyl group suggests strong NH···O intramolecular hydrogen bonding comprising a six‐membered chelate ring. The NH···O hydrogen bond causes an increase of the1J(N,H) coupling constant by 2–4 Hz and high‐frequency shift of the15N signal by 9–10 ppm despite of the lengthening of the relevant NH bond. These experimental trends are substantiated by gauge‐independent atomic orbital and density functional theory calculations of the shielding and coupling constants in the 3,3‐bis(isopropylamino)‐1‐(aryl)prop‐2‐en‐1‐one (12) for conformations with theZ‐ andE‐orientations of the carbonyl group relative to the NH group. The effects of the NH···O hydrogen‐bond on the NMR parameters are analyzed with the atoms‐in‐molecules (AIM) and natural bond orbital (NBO) methods. The AIM method indicates a weakening of the NH···O hydrogen bond as compared with that of 1,1‐di(pyrrol‐2‐yl)‐2‐formylethene (13) where NH···O hydrogen bridge establishes a seven‐membered chelate ring, and the corresponding1J(N,H) coupling constant decreases. The NBO method reveals that the LP(O) →σ*NHhyperconjugative interaction is weakened on going from the six‐membered chelate ring to the seven‐membered one due to a more bent hydrogen bond in the former case. A dominating effect of the NH bond rehybridization, owing to an electrostatic term in the hydrogen bonding, seems to provide an increase of the1J(N,H) value as a consequence of the NH···O hydrogen bonding in the studied diaminoenones. Copyright © 2010 John Wiley & Sons, Ltd.
Ukrainische Wissenschaft – auf dem Weg nach Europa
Authors: Heinrich Lothar 
Published: July 2010

AbstractEine große Zahl hervorragender Nachwuchsforscher und eine besondere Kompetenz in den Materialwissenschaften zeichnen die ukrainische Wissenschaft aus. Die Intensivierung der deutsch‐ukrainischen Zusammenarbeit stärkt die europäische Wettbewerbsfähigkeit.
Altered levels of insulin‐like growth factor binding protein proteases in preeclampsia and intrauterine growth restriction
Authors: Christians Julian K. , Gruslin Andrée 
Published: July 2010

AbstractIntrauterine growth restriction (IUGR) and preeclampsia (PE) are leading causes of perinatal and maternal morbidity and mortality. Many studies have found association between low levels of insulin‐like growth factor binding protein (IGFBP) proteases in the first trimester maternal circulation and the risk of subsequent development of PE and/or IUGR. These results are generally interpreted to reflect decreased production of the proteases by the placenta, leading to reduced proteolysis of IGFBPs and lower free levels of insulin‐like growth factor (IGF), resulting in diminished feto‐placental development. However, the association between low circulating levels of placental proteins early in pregnancy and the subsequent development of IUGR and/or PE could be due to low exchange in the placenta and not due to reduced production. In contrast, late in pregnancy, the circulating levels of these proteins and their expression in the placenta are often elevated in PE, which may reflect upregulation to compensate for abnormal placental development, that is an adaptive mechanism to increase IGFBP proteolysis, increase local IGF levels and promote feto‐placental growth. Further research into the biological mechanisms underlying these associations will aid the identification of high‐risk pregnancies and the development of therapeutic targets for diseases for which there are presently no preventative measures. Copyright © 2010 John Wiley & Sons, Ltd.
Description of hypersensitivity adverse events following administration of heparin that was potentially contaminated with oversulfated chondroitin sulfate in early 2008
Authors: McMahon Ann W. , Pratt Robert G. , Hammad Tarek A. , Kozlowski Steven , Zhou Esther , Lu Susan , Kulick Corrinne G. , Mallick Tarun , Dal Pan Gerald 
Published: July 2010

AbstractPurposeTo characterize the nature of a heparin contaminant's clinical effects in cases reported to the Adverse Event Reporting System (AERS). The FDA received reports of heparin‐associated adverse events (AEs) starting in late 2007–early 2008 during a national investigation of allergic‐type events. The investigation identified Baxter Healthcare‐brand heparin product due to its strongest association with the events. Later, oversulfated chondroitin sulfate (OSCS), a heparin‐like contaminant, was discovered.MethodsThis study was a case series of heparin reports in AERS received 1 January 2008 to 31 March 2008. Variables considered were frequency of treatment settings, AEs, mortality; as well as heparin dose and OSCS contamination.ResultsFive hundred seventy‐four AERS cases (unduplicated reports) were identified and included. Of 94 cases with a fatal outcome, 68 reported at least one AE term from the list used to identify an allergic‐type event. Nearly 75% of AEs in cases of IV administration (n = 170/233) reportedly occurred within 10 minutes, whereas over half of subcutaneous administration cases (n = 13/23) resulted in times‐to‐event of greater than 24 hours. Although cases with a time‐to‐event of less than 10 minutes appeared to correlate with higher levels of OSCS contamination, no clear differences were noted between high‐ and low‐to‐absent OSCS concentration lots with respect to AEs observed.ConclusionsIntravenous administration and a higher OSCS concentration appeared to correlate with a more rapid onset of event. The FDA continues to monitor AEs associated with heparin use and has taken appropriate regulatory action to ensure a safe heparin drug supply. Published in 2010 by John Wiley & Sons, Ltd.
Synthesis and properties of chain‐extended bismaleimide resins containing phthalide cardo structure
Authors: Xiong Xuhai , Chen Ping , Yu Qi , Zhu Nengbo , Wang Baichen , Zhang Jinxiang , Li Jianfeng 
Published: July 2010

AbstractThree novel bismaleimide (BMI) monomers containing phthalide groups in their structures, i.e. 3,3‐bis[4‐(4‐maleimidophenoxy)phenyl]phthalide, 3,3‐bis[4‐(4‐maleimidophenoxy)‐3‐methylphenyl]phthalide and 3,3‐bis[5‐isopropyl‐4‐(4‐maleimidophenoxy)‐2‐methylphenyl]phthalide, based on phenolphthalein, o‐cresolphthalein and thymolphthalein, respectively, were designed and synthesized. The chemical structures of the monomers were confirmed from 1H NMR and 13C NMR spectroscopy and Fourier transform infrared spectroscopy. These monomers exhibit good solubility in common organic solvents, enabling easy solution processing. The thermal curing behavior of the monomers was investigated using differential scanning calorimetry, displaying broad exothermic peaks and large thermal processing windows. Thermogravimetric analysis and dynamic mechanical analysis were used to characterize the thermal stability and thermal mechanical properties of the resulting BMI resins. The results, in contrast to bisphenol A‐based BMI resin, indicate that the incorporation of the phthalide structure into the polybismaleimide network can effectively improve the thermal properties. Water absorption tests of the cured products demonstrate the chemical structure has an effect on moisture resistance. Copyright © 2010 Society of Chemical Industry
A preliminary report on innovative group therapy in an oncology in‐patient department: a patient–family–staff community meeting
Authors: Eliasov Liron , Zalman Daniela , Flechter Ezequiel , Vorobeichik Marina , Halevi‐Gurevich Michal , Levi Inbal , Bar‐Sela Gil 
Published: July 2010

AbstractObjective: The Community Meeting (CM) is a unique form of group therapy applied from Psychiatry to an Oncology in‐patient department. It is designed to answer the needs of in‐patients and family members for open communication and empathic interaction and to serve as a model for effective coping.Methods: A weekly staff–patient–family open group was held, with facilitation based on an integrative crisis intervention model. After each CM, the staff meets to discuss implications.Results: Frequent themes include patient and caregiver concerns about cancer, treatments, communication and coping difficulties. Subjective impressions of participants indicate positive outcomes. The CM seems to enhance positive interactions and perceived quality of care. It helps staff to identify distress, serves as a managerial tool and promotes collaboration among staff.Conclusions: The CM is a unique method for addressing the burdens of in‐patient oncology members. A structured study is needed to substantiate these descriptive outcomes. Copyright © 2010 John Wiley & Sons, Ltd.
The human peripheral subunit‐binding domain folds rapidly while overcoming repulsive Coulomb forces
Authors: Arbely Eyal , Neuweiler Hannes , Sharpe Timothy D. , Johnson Christopher M. , Fersht Alan R. 
Published: July 2010

AbstractPeripheral subunit binding domains (PSBDs) are integral parts of large multienzyme complexes involved in carbohydrate metabolism. PSBDs facilitate shuttling of prosthetic groups between different catalytic subunits. Their protein surface is characterized by a high density of positive charges required for binding to subunits within the complex. Here, we investigated folding thermodynamics and kinetics of the human PSBD (HSBD) using circular dichroism and tryptophan fluorescence experiments. HSBD was only marginally stable under physiological solvent conditions but folded within microseconds via a barrier‐limited apparent two‐state transition, analogous to its bacterial homologues. The high positive surface‐charge density of HSBD leads to repulsive Coulomb forces that modulate protein stability and folding kinetics, and appear to even induce native‐state movement. The electrostatic strain was alleviated at high solution‐ionic‐strength by Debye‐Hückel screening. Differences in ionic‐strength dependent characteristics among PSBD homologues could be explained by differences in their surface charge distributions. The findings highlight the trade‐off between protein function and stability during protein evolution.
Crystal structure of human thioredoxin revealing an unraveled helix and exposed S‐nitrosation site
Authors: Weichsel Andrzej , Kem Michelle , Montfort William R. 
Published: July 2010

AbstractThioredoxins reduce disulfide bonds and other thiol modifications in all cells using a CXXC motif. Human thioredoxin 1 is unusual in that it codes for an additional three cysteines in its 105 amino acid sequence, each of which have been implicated in other reductive activities. Cys 62 and Cys 69 are buried in the protein interior and lie at either end of a short helix (helix 3), and yet can disulfide link under oxidizing conditions. Cys 62 is readily S‐nitrosated, giving rise to a SNO modification, which is also buried. Here, we present two crystal structures of the C69S/C73S mutant protein under oxidizing (1.5 Å) and reducing (1.1 Å) conditions. In the oxidized structure, helix 3 is unraveled and displays a new conformation that is stabilized by a series of new hydrogen bonds and a disulfide link with Cys 62 in a neighboring molecule. The new conformation provides an explanation for how a completely buried residue can participate in SNO exchange reactions.
Core glycan in the yeast multicopper ferroxidase, Fet3p: A case study of N‐linked glycosylation, protein maturation, and stability
Authors: Ziegler Lynn , Terzulli Alaina , Sedlak Erik , Kosman Daniel J. 
Published: July 2010

AbstractGlycosylation is essential to the maintenance of protein quality in the vesicular protein trafficking pathway in eukaryotic cells. Using the yeast multicopper oxidase, Fet3p, the hypothesis is tested that core glycosylation suppresses Fet3p nascent chain aggregation during synthesis into the endoplasmic reticulum (ER). Fet3p has 11 crystallographically mapped N‐linked core glycan units. Assembly of four of these units is specifically required for localization of Fet3p to the plasma membrane (PM). Fet3 protein lacking any one of these glycan units is found in an intracellular high‐molecular mass species resolvable by blue native gel electrophoresis. Individually, the remaining glycan moieties are not required for ER exit; however, serial deletion of these by N → A substitution correlates with these desglycan species failure to exit the ER. Desglycan Fet3 proteins that localize to the PM are wild type in function indicating that the missing carbohydrate is not required for native structure and biologic activity. This native function includes the interaction with the iron permease, Ftr1p, and wild type high‐affinity iron uptake activity. The four essential sequons are found within relatively nonpolar regions located in surface recesses and are strongly conserved among fungal Fet3 proteins. The remaining N‐linked sites are found in more surface exposed, less nonpolar environments, and their conservation is weak or absent. The data indicate that in Fet3p the N‐linked glycan has little effect on the enzyme's molecular activity but is critical to its cellular activity by maximizing the protein's exit from the ER and assembly into a functional iron uptake complex.
Acaricides and their residues in Spanish commercial beeswax
Authors: Serra‐Bonvehí Josep , Orantes‐Bermejo José 
Published: July 2010

AbstractBACKGROUND: The purpose of this work was to determine residues of acaricides in recycled Spanish beeswax.RESULTS: Chlorfenvinphos, fluvalinate, amitraz, bromopropylate, acrinathrin, flumethrin, coumaphos, chlorpyrifos, chlordimeform, endosulfan and malathion residues were determined by GC‐µECD/NPD/MS detection. Owing to the extreme instability of amitraz, this analyte was transformed into the stable end‐metabolite 2,4‐dimethylaniline, later derivatised with heptafluorobutyric anhydride and determined by GC‐µECD/MS. Recoveries from spiked samples ranged from 86 to 108%, while quantification limits varied from 0.10 to 0.30 mg kg−1 using GC‐µECD/NPD, and from 12 to 85 µg kg−1 by GC‐MSD. Of a total of 197 samples analysed, only eight samples (4%) were free of residues of chlorfenvinphos (0.019–10.6 mg kg−1), fluvalinate was present in 93.6% of samples analysed (0.027 –88.7 mg kg−1), while coumaphos was confirmed in only five of the 134 samples analysed at concentrations of less than 195 µg kg−1. The remaining acaricides were identified with different levels of incidence at concentrations from 12 to 231 µg kg−1.CONCLUSIONS: Residues of acaricides were found in an extensive number of beeswax samples. The contamination with chlorfenvinphos and tau‐fluvalinate was very relevant, particularly as chlorfenvinphos is not legally authorised for use in beekeeping. The possible impacts of the main acaricides detected on larval and adult honey bees are discussed. Copyright © 2010 Society of Chemical Industry
Evaluation of chlorfenapyr for control of the bed bug, Cimex lectularius L.
Authors: Romero Alvaro , Potter Michael F , Haynes Kenneth F 
Published: July 2010

AbstractBACKGROUND: The presence of bed bug populations resistant to pyrethroids demands the development of new control tactics, including the use of insecticides with new modes of action. Insecticides that disrupt oxidative phosphorylation in insect mitochondria can be an option. Laboratory assays were used to measure the toxicity of chlorfenapyr to susceptible strains and two strains highly resistant to pyrethroids. The effectiveness of two chlorfenapyr‐based formulations was compared, and behavioral responses of bed bugs to dry residues of aerosol sprays were evaluated.RESULTS: Chlorfenapyr was effective against all bed bug strains, killing them at a similar rate, regardless of their susceptibility status to pyrethroids. Dry residues aged for 4 months were as toxic as fresh dry residues. The aerosol formulation had contact activity and caused faster mortality than a water‐based formulation. Bed bugs did not avoid resting on surfaces treated with aerosol.CONCLUSION: Chlorfenapyr is an option for controlling pyrethroid‐resistant bed bugs. While it does not cause quick knockdown, its long residual activity and no avoidance behavior of bed bugs to dry residues appear to make this insecticide suitable for bed bug control. A faster insecticidal effect is obtained with the aerosol formulation, suggesting greater bioavailablity of the toxicant. Copyright © 2010 Society of Chemical Industry
A demonstration of 4D‐Var using a time‐distributed background term
Authors: Cullen M. J. P. 
Published: July 2010

AbstractThe standard four‐dimensional variational data assimilation (4D‐Var) method used at several major operational centres minimises a cost function which consists of a background term evaluated at the start of the assimilation window and a sum of observation terms evaluated throughout the assimilation window. This method can be interpreted as a smoother in which the background term is evolved in time using the forecast model, and the observations assimilated sequentially. However, in operational practice, the initial estimate of the background error is climatological and highly simplified, so that it is not clear whether this interpretation is useful. We thus interpret the background term as a regularisation term, rather than as an estimate of the true background error. We demonstrate this approach using a toy model whose solutions contain two time‐scales: a slow scale which can be accurately predicted and a fast scale where the model errors are too large for deterministic prediction to be possible. This represents a common situation in operational predictions. We show that, if the regularisation term is only evaluated at the beginning of the assimilation window, as in standard 4D‐Var, it is less effective at controlling rapidly growing modes. This can be resolved by applying the regularisation with equal weight throughout the window. The effect is that, in poorly observed situations, better forecasts of the slow modes can be obtained by directing information from the observations onto the slow modes rather than the unpredictable fast modes. © Crown Copyright 2010. Reproduced with the permission of HMSO. Published by John Wiley & Sons, Ltd.
Impact of denial of service solutions on network quality of service
Authors: Fowler Scott , Zeadally Sherali , Chilamkurti Naveen 
Published: July 2010

AbstractThe Internet has become a universal communication network tool. It has evolved from a platform that supports best‐effort traffic to one that now carries different traffic types including those involving continuous media with quality of service (QoS) requirements. As more services are delivered over the Internet, we face increasing risk to their availability given that malicious attacks on those Internet services continue to increase. Several networks have witnessed denial of service (DoS) and distributed denial of service (DDoS) attacks over the past few years which have disrupted QoS of network services, thereby violating the Service Level Agreement (SLA) between the client and the Internet Service Provider (ISP). Hence DoS or DDoS attacks are major threats to network QoS. In this paper we survey techniques and solutions that have been deployed to thwart DoS and DDoS attacks and we evaluate them in terms of their impact on network QoS for Internet services. We also present vulnerabilities that can be exploited for QoS protocols and also affect QoS if exploited. In addition, we also highlight challenges that still need to be addressed to achieve end‐to‐end QoS with recently proposed DoS/DDoS solutions. Copyright © 2010 John Wiley & Sons, Ltd.
Statistical learning and language acquisition
Authors: Romberg Alexa R. , Saffran Jenny R. 
Published: July 2010

AbstractHuman learners, including infants, are highly sensitive to structure in their environment. Statistical learning refers to the process of extracting this structure. A major question in language acquisition in the past few decades has been the extent to which infants use statistical learning mechanisms to acquire their native language. There have been many demonstrations showing infants' ability to extract structures in linguistic input, such as the transitional probability between adjacent elements. This paper reviews current research on how statistical learning contributes to language acquisition. Current research is extending the initial findings of infants' sensitivity to basic statistical information in many different directions, including investigating how infants represent regularities, learn about different levels of language, and integrate information across situations. These current directions emphasize studying statistical language learning in context: within language, within the infant learner, and within the environment as a whole. WIREs Cogn Sci 2010 1 906–914This article is categorized under:

Linguistics > Language Acquisition
Psychology > Language
A search engine for the global PKI
Authors: Rabinovich Paul 
Published: July 2010

Abstract
Today the public key technology enjoys wide acceptance and use. Countless network protocols and applications use it to guarantee strong authentication and privacy. Usability and maintainability of this technology remains problematic, however. It is still very cumbersome and time-consuming to set up an enterprise Public Key Infrastructure (PKI) that has relationships with external parties. The emergence of PKI bridges, while solving one set of problems, created a new one: management of distributed trust became much more difficult. Complexity of the global PKI mesh and its decentralized nature created a need for a service with a unified view of the global PKI. In this paper we propose a PKI search engine that can provide such a service. The engine supports facilities for certificate and certificate revocation list (CRL) discovery, testing and troubleshooting of extra-enterprise PKIs, certificate revocation status lookup, certification path construction and validation, all based on the Internet-mined and user-registered information.