bluuebunny/crossref_metadata_2025 huggingface dataset:
Data Processing Tools Help Optimize Drilling and Related Operations
Authors: Planeix Michéle Y.
Published: December 2007

Thanks to great technological advances, computer applications, as well as computers themselves, originally limited to huge scientific calculations, have been considerably diversified. Data processing can now be combined with office computer equipment and with telecommunications, to offer a very large range of solutions to various problems.

In order to arrive at a reliable, rational and economically satisfying solution, the computerization study must be above all exhaustive. Most difficulties and failures in this field are due to the fact that some aspect of the problem was underestimated and even perhaps omitted.

When a data processing system is connected to an existing task, it will no doubt disturb it. Very often this situation is not accepted.

Thus the acceptance of such a system depends on mastering the psychological as well as technical and economical factors.

In this paper we'll try to show how data processing can help engineers and field personnel to plan and drill more safely, faster and less expensively; and how it can help managers in administrating and planning. Two poles of interest will be considered: –the field,–the local or head office.

Aditionally we shall show on an example, how the computer can be used to visualize operations timetables where various operations need to be coordinated, by the use of the Program Evaluation and Review Technique. The method is applied to the organization of a blow out kill in our example.
Overcoming the drawbacks of natural coagulants for drinking water treatment
Authors: Ghebremichael K.
Published: December 2007

A number of natural coagulants from plants or animal origin can be effectively used for the treatment of drinking water. Some are used at household levels in traditional systems using crude (non-purified) extract. In the crude extract form, natural coagulants release organic and nutrient loads to the water resulting in poor treated water quality. In such cases it becomes necessary to purify the coagulant component from the crude extract before using it for water treatment. This paper discusses an effective and simple purification of the coagulant from Moringa oleifera seed using an ion exchange method that would overcome the drawbacks of natural coagulants. The impact of the purification process on reducing organic and nutrient release was studied. Adsorption and elution parameters of the ion exchange process were optimised. The study indicated that the purified protein has effective coagulation activity and it did not release organic and nutrient loads to the water. Compared to other purification methods used in previous studies, this is simple and of comparatively lower cost. This purification method can be readily scaled up and applied even in remote parts of developing countries. This work suggests that the concerns of natural coagulants can be overcome by simple purification and this is believed to promote their use in drinking water treatment.
Immersion française et élèves à risques: revue des données de recherche
Authors: Genesee Fred
Published: December 2007

Abstract:

This report reviews results of research on the outcomes of French immersion students with special educational needs related to low levels of general academic ability and low levels of first language ability (and possibly impairment), as well as those of students with difficulty or who are at risk for difficulty in learning to read. Studies of the effectiveness of interventions for such students are also reviewed and analyzed. The report ends with suggestions for future research and educational policy.
Biological Functionalization of a Sol–Gel Coating for the Mitigation of Microbial‐induced Corrosion
Authors: Akid R. , Wang H. , Smith T. J. , Greenfield D. , Earthman J. C.
Published: December 2007

The addition of biocides to water systems has been the most direct attempt to limit or mitigate the formation of surface biofilms that lead to the development of microbial‐induced corrosion (MIC), a process that costs industry millions of pounds annually. The efficacy of this approach is dependent upon a) the biocide being delivered to all water–metal substrate interaction sites and b) the biocide remaining active, therein preventing biofilm development/growth. Anti‐fouling biocide additions to water supplies, or anti‐fungal additives in paints, have an adverse impact upon the environment, for example, tri‐butyl tin is toxic to aquatic life. An alternative non‐toxic approach currently being pursued by the authors involves localizing a biologically active reagent close to the metal substrate. Localization in this case is achieved by synthesizing a hybrid functional sol–gel coating and encapsulating a suitable non‐pathogenic biological component within the sol–gel matrix. Distribution within the sol–gel coating of vegetative bacteria or spores has been confirmed using various microscopy techniques. Electrochemical data in the form of polarization resistance, impedance spectroscopy, and electrochemical noise all show that the presence of either P. fragi or P. polymyxa within a sol–gel coating leads to a corrosion resistance improvement at least 10 times that of an equivalent abiotic coating. Confirmation of this improvement is derived from six months of field trial testing conducted in a tidal estuarine environment. Comparative tests that use a control sol–gel coating immersed within nutrient poor artificial seawater that contained freely suspended P. polymyxa reveal no marked improvement over a control sample in the absence of the endospores.
Catalytic Asymmetric Alkynylation and Arylation of Aldehydes by an H8‐Binaphthyl‐Based Amino Alcohol Ligand
Authors: Ruan Jiwu , Lu Gui , Xu Lijing , Li Yue‐Ming , Chan Albert S. C.
Published: December 2007

A novel chiral H8‐1,1′‐binaphthyl‐based amino alcohol ligand (1Ra,2S,3R)‐2 has been synthesized and applied in the direct nucleophilic addition of organozincs (alkynylzinc and arylzinc prepared in situ) to aldehydes, yielding the corresponding optically active propargylic alcohols and diarylmethanols in high yields and good to excellent enantioselectivities. For the asymmetric arylation reaction, one catalyst (1Ra,2S,3R)‐2 can afford both enantiomers of many pharmaceutically interesting diarylmethanols by a proper combination of various arylzinc reagents and aldehydes.
Inorganic Nanoparticles as Carriers of Nucleic Acids into Cells
Authors: Sokolova Viktoriya , Epple Matthias
Published: December 2007

The transfer of nucleic acids (DNA or RNA) into living cells, that is, transfection, is a major technique in current biochemistry and molecular biology. This process permits the selective introduction of genetic material for protein synthesis as well as the selective inhibition of protein synthesis (antisense or gene silencing). As nucleic acids alone are not able to penetrate the cell wall, efficient carriers are needed. Besides viral, polymeric, and liposomal agents, inorganic nanoparticles are especially suitable for this purpose because they can be prepared and surface‐functionalized in many different ways. Herein, the current state of the art is discussed from a chemical viewpoint. Advantages and disadvantages of the available methods are compared.
Direct enzymatic glucosylation of naringin in grapefruit juice by α‐D‐glucosidase from the marine mollusc Aplysia fasciata
Authors: Tramice Annabella , Andreotti Giuseppina , Trincone Antonio
Published: December 2007

The enzymatic glucosylations of naringin, performed using α‐D‐glucosidase, identified in the Mediterranean mollusc Aplysia fasciata is reported. The enzyme actively operates on maltose and has an interesting transglycosylation potential using this donor. We also investigated the use of this marine α‐glucosidase for a food‐compatible glucosylation of naringin to produce new enzymatically modified carbohydrate possessing naringin derivatives. The regioselective formations of the β‐gluco‐C6 α‐glucosyl derivative and of the corresponding isomaltosyl diglucoside of naringin were obtained in high yield and efficiency of reaction. Suspensions of naringin can be used up to ∼90 mg/mL initial acceptor concentration. In different experiments it was demonstrated that the enzyme was still active after 48 h in presence of this high amount of acceptor and that one of the diasteromers of the naringin is preferred by the enzyme from A. fasciata during glucosylation/deglucosylation enzymatic steps. Finally, the feasibility of efficient naringin glucosylation in grapefruit juice was also demonstrated at optimal pH of the enzyme and low maltose concentrations.
Percutaneous intervention on the saphenous vein bypass grafts—Long‐term outcomes
Authors: Bansal Darpan , Muppidi Raghu , Singla Sandeep , Sukhija Rishi , Zarich Stuart , Mehta Jawahar L. , Sachdeva Rajesh
Published: December 2007

Background/Objective: In this era of drug eluting stents (DES), the long‐term outcome of percutaneous intervention (PCI) on saphenous venous grafts (SVG) is unknown. The objective of the study was to compare the long‐term outcomes of DES versus bare metal stent (BMS) in this population and to determine the predictors of outcomes. Methods: We reviewed the medical records of all patients who had PCI performed during January 2003 to February 2005 to obtain data cardiac risk factors, medications at discharge, angiographic details and outcomes. Results: One hundred and nine patient had PCI to SVG; of these, 37 patients received DES and the remaining had BMS. Over a mean follow‐up of 33 months, the PCI using DES was associated with 30% restenosis, 35% target vessel revascularization (TVR) and major adverse cardiac event (MACE) rate of 46% versus 35% restenosis, 38% TVR and 50% MACE rate with BMS. There was no significant difference in long‐term outcome with DES as compared to BMS. Conclusion: There was no difference in the long‐term outcomes of PCI on SVG irrespective of the type of stent used. © 2008 Wiley‐Liss, Inc.
ChemInform Abstract: An Efficient, Simple, One Pot Synthesis of Dihydropyrimidine‐2(1H)‐ones Using Phosphorus Pentoxid.
Authors: Deshmukh M. B. , Anbhule Prashant V. , Jadhav S. D. , Mali A. R. , Jagtap S. S. , Deshmukh S. A.
Published: December 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Pegylated liposomal doxorubicin as second‐line therapy in the treatment of patients with advanced classic Kaposi sarcoma
Authors: Di Lorenzo Giuseppe , Di Trolio Rossella , Montesarchio Vincenzo , Palmieri Giovanna , Nappa Paola , Delfino Mario , De Placido Sabino , Dezube Bruce J.
Published: December 2007

BACKGROUND.

Classic Kaposi sarcoma (CKS) is a rare neoplasm that predominantly occurs in elderly subjects and has a variable clinical evolution. The clinical course is usually indolent, but occasionally the neoplasm progresses rapidly and spreads to internal organs, necessitating systemic chemotherapy. Because of the rarity of CKS, the best treatment has not been determined to date. To the authors' knowledge, few data exist regarding the use of pegylated liposomal doxorubicin (PLD) as first‐line and second‐line treatment in advanced CKS. The current retrospective study investigated the activity and toxicity of PLD in pretreated patients with aggressive, nonvisceral CKS.

METHODS.

Patients were treated with PLD at a dose of 20 mg/m2 intravenously every 3 weeks until disease progression or the occurrence of intolerable side effects. Objective responses were determined after 3 and 6 cycles; toxicity was assessed every cycle. Secondary endpoints were pain intensity, progression‐free survival, and overall survival.

RESULTS.

Twenty men with pretreated CKS (median age, 67 years) were treated with PLD. All patients received at least 6 cycles of therapy. Complete and partial responses were observed in 2 patients (10%) and 14 patients (70%), respectively. Neutropenia was the most significant grade 3 hematologic toxicity observed (evaluated according to the National Cancer Institute Common Toxicity Criteria for Adverse Events [version 3.0]), occurring in 20% of patients. Only 1 patient (5%) demonstrated grade 4 neutropenia. Fourteen patients (70%) achieved remission of pain and/or edema after 6 cycles. The median progression‐free survival was 9 months (95% confidence interval, 5–13 months). At a median follow‐up of 36 months, 15 patients (75%) remained alive.

CONCLUSIONS.

PLD is associated with an improvement in objective response and pain intensity and is well tolerated as a second‐line treatment for CKS. Cancer 2008. © 2007 American Cancer Society.
TGF‐β signaling is dynamically regulated during the alveolarization of rodent and human lungs
Authors: Alejandre‐Alcázar Miguel A. , Michiels‐Corsten Matthias , Vicencio Alfin G. , Reiss Irwin , Ryu Julie , de Krijger Ronald R. , Haddad Gabriel G. , Tibboel Dick , Seeger Werner , Eickelberg Oliver , Morty Rory E.
Published: December 2007

Although transforming growth factor‐beta (TGF‐β) signaling negatively regulates branching morphogenesis in early lung development, few studies to date have addressed the role of this family of growth factors during late lung development. We describe here that the expression, tissue localization, and activity of components of the TGF‐β signaling machinery are dynamically regulated during late lung development in the mouse and human. Pronounced changes in the expression and localization of the TGF‐β receptors Acvrl1, Tgfbr1, Tgfbr2, Tgfbr3, and endoglin, and the intracellular messengers Smad2, Smad3, Smad4, Smad6, and Smad7 were noted as mouse and human lungs progressed through the canalicular, saccular, and alveolar stages of development. TGF‐β signaling, assessed by phosphorylation of Smad2, was detected in the vascular and airway smooth muscle, as well as the alveolar and airway epithelium throughout late lung development. These data suggest that active TGF‐β signaling is required for normal late lung development. Developmental Dynamics 237:259–269, 2008. © 2007 Wiley‐Liss, Inc.
An energy trading system with consideration of CO2 emissions
Authors: Miyamoto Toshiyuki , Kitayama Tomohiro , Kumagai Sadatoshi , Mori Kazuyuki , Kitamura Syoichi , Shindo Seiichi
Published: December 2007

Abatement of CO2 emission is one of the most important issues in the 21st century regarding preservation of the earth environment. This paper addresses a utility operations planning problem for distributed energy management systems (DEMSs), where we are to obtain optimal plans that minimize both costs and CO2 emissions. A DEMS consists of multiple entities that seek their own economic profits. In this paper, we give a mathematical formulation of the utility operations planning problem for each entity, and propose an energy trading market, which utlizes a multi‐attribute auction protocol in order to deal with both a price and a CO2 emission rate. Experimental results show that collaboration among entities through the market provides a more profitable plan for each entity and abatement of CO2 emission is also achieved. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 54–63, 2008; Published online in Wiley InterScience (www.interscience.wiley. com). DOI 10.1002/eej.20418
CTLA‐4 disrupts ZAP70 microcluster formation with reduced T cell/APC dwell times and calcium mobilization
Authors: Schneider Helga , Smith Xin , Liu Hebin , Bismuth Georges , Rudd Christopher E.
Published: December 2007

CTLA‐4 is a co‐receptor that modulates the threshold of T cell activation and autoimmunity. We previously showed that CTLA‐4 reverses the TCR‐mediated stop signal needed for T cell/APC interactions [Schneider et al., Science 2006, 313: 1972]. In this study, using a different T cell system, we show that CTLA‐4 expression changed the behavior of T8.1 T cells by reducing the contact time between T cell and APC, preventing re‐inforced contacts, and reducing the contact area at the immunological synapse. This led to a major reduction in Ca2+ influx/mobilization and interleukin‐2 production. Further, anti‐CD3/CTLA‐4 increased T cell motility on antibody‐coated glass slides, concurrent with an abrogation of ZAP70 microcluster formation. Our findings further support a role for CTLA‐4 in limiting the interaction between T cell and APC that is needed for optimal activation.
New Push‐Pull Chromophores Featuring TCAQ (11,11,12,12‐Tetracyano‐ 9,10‐anthraquinodimethane) and Other Dicyanovinyl Acceptors
Authors: Bureš Filip , Schweizer W. Bernd , Boudon Corinne , Gisselbrecht Jean‐Paul , Gross Maurice , Diederich François
Published: December 2007

Stable, highly colored push‐pull chromophores with NMe2 donor and C=C(CN)2 acceptor moieties, featuring intense intramolecular charge‐transfer (CT) bands in the UV/Vis spectra, are reported. In an attempt to prepare the quinoid push‐pull systems 2, chromophores 10 and 11, with a central cyclohexene spacer, were obtained and characterized by X‐ray analysis. A series of donor‐substituted TCAQ (11,11,12,12‐tetracyano‐9,10‐anthraquinodimethane) derivatives were synthesized, using the Knoevenagel condensation between appropriately functionalized anthraquinones and malononitrile, mediated by the Lehnert reagent (TiCl4/pyridine), as the key step. HCl addition to triple bonds was observed when this transformation was applied to alkynylated anthraquinones. Electrochemical studies by cyclic voltammetry (CV) and rotating‐disk voltammetry (RDV) showed that introduction of donor substituents into the TCAQ core of 25, 26, and 31 shifts the first reduction potential to more negative values, while chromophores bearing guanidine moieties (27, 28) displayed a specific and complex redox behavior. Both electrochemical and UV/Vis data provide good evidence that D–A conjugation is more efficient through olefinic (in 10) than through acetylenic (in 37) spacers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
MicroRNA epigenetic alterations in human cancer: One step forward in diagnosis and treatment
Authors: Yang Nuo , Coukos George , Zhang Lin
Published: December 2007

MicroRNAs (miRNAs) are approximately 22 nt non‐coding RNAs, which regulate gene expression in a sequence‐specific manner via translational inhibition or messenger RNA (mRNA) degradation. Since the discovery of their fundamental mechanisms of action, the field of miRNAs has opened a new era in the understanding of small noncoding RNAs. By molecular cloning and bioinformatic approaches, miRNAs have been identified in viruses, plants and animals. miRNAs are predicted to negatively target up to one‐third of human mRNAs. Cancer is a complex genetic disease caused by abnormalities in gene structure and expression. Previous studies have heavily focused on protein‐coding genes; however, accumulating evidence is revealing an important role of miRNAs in cancer. Epigenetics is defined as mitotically and/or meiotically heritable changes in gene expression that are not accompanied by changes in DNA sequence. Given the critical roles of miRNAs and epigenetics in cancer, characterizing the epigenetic regulation of miRNAs will provide novel opportunities for the development of cancer biomarkers and/or the identification of new therapeutic targets in the foreseeable future. © 2007 Wiley‐Liss, Inc.
The local inflammatory environment and microorganisms in “aseptic” loosening of hip prostheses
Authors: Hoenders Caroline S. M. , Harmsen Marco C. , van Luyn Marja J. A.
Published: December 2007

Long term loosening of hip prostheses remains an important problem in orthopedics. Although various loosening mechanisms have been proposed, the exact process is still unclear. Particle disease and the pressure theory are widely known and generally accepted hypotheses to explain long term implant failure. Each proposed mechanism recognizes a local inflammatory response in which macrophages represent the main cell‐type and several proinflammatory and antiinflammatory cytokines (IL‐1β, IL‐6, TNFα, IL‐10, TGFβ), chemokines (IL‐8/CXCL8, MCP‐1/CCL2, RANTES/CCL5, MIP‐1α/CCL3) and other mediators (GM‐CSF, M‐CSF, MMP‐1, PDGF‐α, PGE2, IL‐11) are identified. The cytokines have different functions and some are capable of stimulating bone resorption in various ways; either directly or indirectly. Even though the implant loosening is thought to be “aseptic”, several studies suggested a possible role for bacteria and a bacterial biofilm in implant failure. Biofilm‐derived bacteria and bacterial products might have an underestimated and potential role in the loosening process. In this article we will discuss the possible role of a bacterial biofilm and the importance of the local surrounding environment in “aseptic” loosening of hip prostheses. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Molecular epidemiology of HIV‐1 subtypes and drug resistant strains in Taiwan
Authors: Lan Yu‐Ching , Elbeik Tarek , Dileanis JoAnn , Ng Valerie , Chen Yen‐Ju , Leu Hsieh‐Shong , Cheng Shu‐Hsing , Wong Jen‐Chien , Wong Wing‐Wai , Chen Yi‐Ming A.
Published: December 2007

The Taiwanese government has provided free highly active antiretroviral therapy since April 1997. Previously, we have reported on the molecular epidemiology of HIV‐1 in Taiwan from 1988 to 1998. In addition, an outbreak of circulating recombinant form (CRF) 07_BC among intravenous drug users was noted in 2004. Therefore, the purposes of this study were to elucidate the distribution of HIV‐1 subtypes among different high‐risk groups in Taiwan from 1999 to 2000 and to conduct surveillance on drug resistance among treatment naïve patients from 1997 to 2000. Blood samples from 239 HIV‐1/AIDS patients and their subtypes were examined using DNA sequencing and phylogenetic analysis. The results showed that among 226 male patients, 213 (94.2%) had subtype B, 11 (4.9%) had CRF01_AE, 1 had unique recombinant strain related to both CRF07_BC and CRF08_BC (strain T12‐99TW) and 1 had CRF08_BC (strain L9312‐00TW). The patients infected with T12‐99TW and L9312‐00TW were intravenous drug users and had needle‐sharing experiences in Yunnan Province, China. Of the 13 HIV‐1‐infected females, 7 (53.8%) had subtype B, 5 (38.5%) had CRF01_AE, and 1 (7.7%) had subtype C. Phylogenetic analysis demonstrated that the neither strain T12‐99TW nor L9312‐00TW clustered with CRF07_BC strains isolated from Taiwanese intravenous drug users in 2004. In addition, 126 treatment naïve patients were selected for genotypic DR analysis and the results showed that 4.3% (2/47) homosexual males had M184V mutations. This is the first report on the identification of CRF08_BC and a unique recombinant strain related to both CRF07_BC and CRF08_BC in Taiwan. J. Med. Virol. 80:183–191, 2008. © 2007 Wiley‐Liss, Inc.
Quantitative temporal and spatial distribution of adenovirus type 2 correlates with disease manifestations and organ failure during disseminated infection
Authors: Forstmeyer Dirk , Henke‐Gendo Cornelia , Bröcker Verena , Wildner Oliver , Heim Albert
Published: December 2007

Disseminated adenovirus (HAdV) infections are serious complications in allogenic stem cell transplant (SCT) recipients. Quantitative HAdV DNA detection in blood samples demonstrated the association of high virus loads with disease and improved early diagnosis. However, the pathogenesis of disseminated HAdV disease, for example sources of HAdV DNA shedding in the blood stream and association of HAdV replication sites with disease manifestations, remained obscure. In this report, 24 bioptic and autoptic organ and tissue samples of an adult SCT recipient suffering from disseminated infection were quantitatively analyzed for HAdV DNA. Results indicate subsequent virus replication in the colon, bone marrow and liver as origin of HAdV DNAemia, which increased from 1.4 × 104 copies/ml to a peak of 2 × 109 copies/ml over a period of 84 days in spite of antiviral therapy. Symptoms as diarrhoea, bone marrow failure and hepatic failure were clearly linked to high HAdV DNA concentrations in affected organs. For example, the HAdV DNA level was 2.2 × 103 copies/cell in a colon biopsy when the patient suffered from diarrhoea whereas only 1.1 × 101 copies/cell were detected when symptoms had improved. Focal HAdV infection of the liver as demonstrated by laser microdissection was followed by fulminant virus replication with 1.3 × 105 copies of HAdV DNA/cell causing terminal hepatic failure. In conclusion, pathogenesis of disseminated HAdV disease was associated with virus replication in affected organs and not immune mediated as suggested recently by a fatal case of gene therapy with a non‐replication competent HAdV‐C5 vector. J. Med. Virol. 80:294–297, 2008. © 2007 Wiley‐Liss, Inc.
Strichartz estimates in Wiener amalgam spaces for the Schrödinger equation
Authors: Cordero Elena , Nicola Fabio
Published: December 2007

We study the dispersive properties of the Schrödinger equation. Precisely, we look for estimates which give a control of the local regularity and decay at infinity separately. The Banach spaces that allow such a treatment are the Wiener amalgam spaces, and Strichartz‐type estimates are proved in this framework. These estimates improve some of the classical ones in the case of large time. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐Ideal Polymerization Kinetics of a Cationic Double Charged Acryl Monomer and Solution Behavior of the Resulting Polyelectrolytes
Authors: Losada Ricardo , Wandrey Christine
Published: December 2007

The radical polymerization of bis‐1,3(N,N,N‐trimethylammonium)‐2‐propylmethacrylate dichloride revealed non‐ideality with 0.59 and 4.4 for the reaction orders of the initiator and monomer concentration, respectively. Further, autoacceleration was observed from less than 10% conversion onwards. Degradative chain transfer to the monomer was concluded to explain the initiator exponent. Monomer association and electrostatic effects are hypothesized to govern the monomer exponent and autoacceleration. The exponential concentration dependent increase of the viscosity of the monomer solution and the relatively low overall activation energy Ea = 31.5 kJ · mol−1 support the hypothesis. Counterion activity measurements confirmed strong counterion condensation as expected for a charge distance of 0.12 nm.

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Application of optical coherence tomography in nacre identification and characterization
Authors: Zeng Nan , He Yonghong , Ma Hui
Published: December 2007

In this article optical coherence tomography is first applied in research on nacre of pearls and mother oysters. The nondestructive OCT measurement can show the shell‐nucleus features, quantify the nacre thickness and unveil hierarchical structure during nacre formation. The experimental results show the potential of OCT imaging in pearl identification and cultivation. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 442–445, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23124
Inverse H‐C ex situ HRMAS NMR experiments for solid‐phase peptide synthesis
Authors: Ramadhar Timothy R. , Amador Fernando , Ditty Michael J. T. , Power William P.
Published: December 2007

The growing importance of solid‐phase peptide synthesis (SPPS) has necessitated the development of spectroscopic experiments that can be used to obtain structural and conformational information on resin‐bound peptides. Despite the utility of two‐dimensional high‐resolution magic angle spinning (HRMAS) NMR experiments that provide homonuclear shift correlations, experiments that provide heteronuclear shift correlations are necessary for complex conformational and structural elucidatory problems. Here we report the optimization and implementation of non‐gradient inverse NMR experiments for acquiring the 1H13C shift correlations of resin‐bound peptides. The use of non‐gradient experiments is advantageous as many magic angle spinning (MAS) probes do not possess gradient coils. An HRMAS BIRD‐HMQC experiment with a reduced 1JCH constant has proven very suitable for obtaining one‐bond correlations. Long‐range correlations can be interpolated by using a non‐gradient HRMAS CT‐HMBC‐1 experiment where the resulting data is processed with forward linear prediction. It has been shown that removing the effects of 1H1H J‐modulation is crucial in order to view cross peaks that correspond to long‐range correlations. Additionally, both experiments prove extremely useful over routine one‐dimensional 13C HRMAS experiments for extracting carbon chemical shift data. The non‐gradient HRMAS BIRD‐HMQC and CT‐HMBC‐1 experiments can be used to assist in conformational analysis and to identify and deconvolute situations where accidental equivalence and seemingly correlated isochronous signals arise. Copyright © 2008 John Wiley & Sons, Ltd.
Structural determination of salsolins A and B, new antioxidant polyoxygenated triterpenes from Salsola baryosma, by 1D and 2D NMR spectroscopy
Authors: Ahmad Zaheer , Mehmood Sajid , Fatima Itrat , Malik Abdul , Ifzal Rehana , Afza Nighat , Iqbal Lubna , Latif Mehreen , Nizami Tanveer Ahmad
Published: December 2007

Salsolins A (1) and B (2), the new triterpenes, have been isolated from the chloroform soluble fraction of Salsola baryosma along with 2α,3β,23,24‐tetrahydroxyurs‐12‐en‐28‐oic acid (3) reported for the first time from this species. Their structures have been assigned from 1H and 13C NMR spectra, DEPT and by 2D COSY, NOESY, HMQC and HMBC experiments. The compounds 1–3 showed significant antioxidant activity. Copyright © 2008 John Wiley & Sons, Ltd.
Full NMR analysis of annomontine, methoxy‐ annomontine and N‐hydroxyannomontine pyrimidine‐β‐carboline alkaloids
Authors: Costa Emmanoel Vilaça , Pinheiro Maria Lúcia Belém , de Souza Afonso Duarte Leão , dos Santos Adriane Gama , Campos Francinete Ramos , Ferreira Antonio Gilberto , Barison Andersson
Published: December 2007

Using modern NMR techniques, including 1H13C and 1H15N heteronuclear correlation experiments, the complete and unambiguous 1H, 13C, and 15N NMR chemical shift assignments of annomontine, methoxyannomontine, and N‐hydroxyannomontine pyrimidine‐β‐carboline alkaloids were performed. All 1H1H scalar coupling constants and signal multiplicities were determined, and all nOe observations were also included. Copyright © 2008 John Wiley & Sons, Ltd.
NMR spectral assignments of a new [COC] isoflavone dimer from Andira surinamensis
Authors: de Almeida José Gustavo L. , Silveira Edilberto R. , Pessoa Otília Deusdênia L.
Published: December 2007

The phytochemical investigation of extracts from the branch wood and branch barks of Andira surinamensis yielded a novel isoflavone dimer, 4′‐methoxyisoflavone‐(7‐O‐7″)‐3″′,4″′‐methylenedioxyisoflavone (surinamensin), along with the triterpene lupeol and the known isoflavones 5,7‐dihydroxy‐4′‐methoxyisoflavone (biochanin A), 5,4′‐dihydroxy‐7‐methoxyisoflavone (prunetin), 7,3′‐dihydroxy‐4′‐methoxyisoflavone (calycosin), and 5,7,3′‐trihydroxy‐4′‐methoxyisoflavone (pratensein). The structure of the new isoflavone was elucidated by 1D and 2D homonuclear and heteronuclear NMR spectroscopy and by comparison with published data for closely related compounds. Copyright © 2008 John Wiley & Sons, Ltd.
An experimental study of decoupling sequences for multiple‐quantum and high‐resolution MAS experiments in solid‐state NMR
Authors: Thakur Rajendra Singh , Kurur Narayanan D. , Madhu P. K.
Published: December 2007

Recently, a sequence for heteronuclear dipolar decoupling in solid‐state NMR, namely SWf‐TPPM, was introduced by us. Under magic‐angle spinning (MAS), the decoupling efficiency of the sequence was unaffected over a range of values for various experimental parameters such as the pulse length, pulse phase, and 1H resonance offset. We here demonstrate its use in multiple‐quantum (MQ) and high‐resolution (HR) MAS experiments. This sequence further improves the MQMAS spectra compared to the earlier reported decoupling sequences with improved immunity to any missets of the pulse length, pulse phase and decoupler offset. In contrast, for HRMAS, the simple CW scheme is as efficient as any of the decoupling schemes that were studied. Copyright © 2007 John Wiley & Sons, Ltd.
A solid‐state 53Cr NMR study of chromate and dichromate salts
Authors: Forgeron Michelle A. M. , Wasylishen Roderick E.
Published: December 2007

Solid‐state 53Cr NMR spectra of a series of chromate (CrO42−) and dichromate (Cr2O72−) salts have been examined by employing the stepped‐frequency quadrupolar Carr‐Purcell Meiboom‐Gill (QCPMG) experiment and high applied magnetic field strengths, 11.75 and 18.8 T. Cr‐53 nuclear quadrupolar coupling constants, CQ(53Cr), ranging from 1.23 to 5.01 MHz for the CrO42− salts and 7.25 to 8.14 MHz for the Cr2O72− salts have been measured. For the dichromate salts, this corresponds to central transition 53Cr NMR lineshapes of 200–250 kHz at 18.8 T. The use of hyperbolic secant (HS) pulses in combination with the Hahn‐echo (HE) or QCPMG experiment results in significant sensitivity enhancements when acquiring 53Cr NMR spectra of magic‐angle spinning (MAS) samples, provided the MAS rate is fast with respect to the second‐order quadrupolar interaction. For the CrO42− and Cr2O72− salts, the anisotropic chromium magnetic shielding interaction is generally negligible compared to the second‐order 53Cr nuclear quadrupolar interaction. No simple correlation between the structure of the CrO42− and Cr2O72− anions and the observed CQ(53Cr) values has been found. Copyright © 2007 John Wiley & Sons, Ltd.
Solid‐state NMR studies and DFT calculations of flavonoids: baicalein, baicalin and wogonoside
Authors: Wolniak Michał , Oszmiański Jan , Wawer Iwona
Published: December 2007

Three flavonoids of pharmaceutical importance—baicalein, baicalin, and wogonoside—were isolated from a Chinese medicinal plant Scutellaria baicalensis Georgi and studied by 13C NMR in solution and solid state. Two‐dimensional (2D) NMR spectroscopy in the liquid phase and dipolar dephasing (DD) experiments in magic‐angle spinning (MAS) spectra enabled the assignment of 13C resonances. The cross‐polarization (CP) time constants TCH and relaxation times TH1ρ were obtained from the variable‐contact time experiments. The principal elements of the 13C chemical shift tensor were determined in the spectra recorded under slow sample spinning (2 kHz) using phase‐adjusted spinning sideband (PASS)‐2D NMR technique, and were verified by density functional theory gauge‐independent atomic orbital (DFT GIAO) calculations of shielding constants. Analysis of the 13C δii and comparison with shielding parameters calculated for different conformers of compounds 1–3 enabled the selection of the most reliable geometry in the solid phase. In all three compounds, an intramolecular hydrogen bond C5OH···C4 is formed; the existence of baicalein and baicalin with ‘anticlockwise’ orientation of OH groups is more probable. Copyright © 2007 John Wiley & Sons, Ltd.
Diffusion‐based MR methods for bone structure and evolution
Authors: Sigmund E.E. , Cho H. , Chen P. , Byrnes S. , Song Y.‐Q. , Guo X.E. , Brown T. R.
Published: December 2007

A new approach to MR trabecular bone characterization is presented. This method probes the diffusion of spins through internal magnetic field gradients due to the susceptibility contrast between the bone and water (or marrow) phases. The resulting spin magnetization decay encodes properties of the underlying structure. This method, termed decay due to diffusion in the internal field (DDIF), is well established as a probe of pore size and structure. In the present work its application is shown for in vitro experiments on excised bovine tibiae samples. A comparison with pulsed field gradient (PFG) measurement of restricted diffusion shows a strong correlation of DDIF with the surface‐to‐volume ratio (SVR) of bones. Calculation of the internal magnetic field within the bone structure also supports this interpretation. These NMR measurements compare well with the image analysis from microscopic computed tomography (μCT). The SVR is not accessible in the clinically standard densitometry measurements, and provides vital information on bone strength and therefore on its fracture risk. The DDIF and PFG methods derive this information from a straightforward pulse sequence that does not employ either high applied field gradients or microimaging, and thus may have clinical potential. Magn Reson Med 59:28–39, 2008. © 2007 Wiley‐Liss, Inc.
Cs + ADC in rat brain decreases markedly at death
Authors: Goodman James A. , Ackerman Joseph J.H. , Neil Jeffrey J.
Published: December 2007

Spectroscopic resolution of intracellular and extracellular compartments can be used to probe the kinetic environment of those spaces and the compartment‐specific changes that occur following injury. This is important for understanding the biophysical mechanisms that underlie the remarkable diffusion‐weighted MRI contrast of injured central nervous system (CNS) tissue. Cesium‐133 is a physiologic analog of potassium that is actively taken up by cells and resides primarily in the intracellular space. The 133Cs+ signal can, thus, be exploited to probe the kinetic environment of the intracellular space. Two principal 133Cs+ resonances were observed at 11.74 T. These resonances arise separately from 133Cs+ in brain and temporalis muscle. The apparent diffusion coefficient (ADC) of Cs+ in brain decreased from 1.0 ± 0.2 μm2/ms in healthy tissue to 0.24 ± 0.04 μm2/ms following global ischemia (average ADC ± average uncertainty), while there was no significant change in the ADC of Cs+ in temporalis muscle after injury. This finding underscores the tissue‐specific nature of the decrease in ADC that accompanies brain injury. Further, as the Cs+ ADC should reflect water ADC in the intracellular space, these results strongly support the hypothesis that the decrease in water ADC associated with CNS injury arises largely from kinetic changes taking place in the intracellular space. Magn Reson Med 59:65–72, 2008. © 2007 Wiley‐Liss, Inc.
PlyC, a novel bacteriophage lysin for compartment‐ dependent proteomics of group A streptococci
Authors: Köller Thomas , Nelson Daniel , Nakata Masanobu , Kreutzer Michael , Fischetti Vincent A. , Glocker Michael O. , Podbielski Andreas , Kreikemeyer Bernd
Published: December 2007

Streptococcus pyogenes (Spy) (group A streptococci) is an important and exclusively human bacterial pathogen, which uses secreted and surface‐associated proteins to circumvent the innate host defense mechanisms and to adhere and internalize into host cells. Thus, investigation of the bacterial extracellular compartments, including secreted and cell wall‐associated subproteomes, is crucial for understanding adherence, invasion, and internalization mechanisms as major steps of Spy pathogenesis. Here, we compared a bacteriophage encoded cell wall hydrolase, PlyC, a multimeric lysin of the C1 bacteriophage, with the established glycosidase, mutanolysin, from Streptomyces globisporus for their suitability to efficiently digest Spy cell walls and release cell wall‐anchored Spy proteins for subsequent proteome research. Our results show that PlyC is superior for cell wall protein extraction compared to mutanolysin due to its higher activity and specificity as an N‐acetylmuramoyl‐L‐alanine amidase. Furthermore, our experimental design allowed us to delineate the actual localization of the proteins despite contamination with intracellular proteins.
Early manganese‐toxicity response in Vigna unguiculata L. – a proteomic and transcriptomic study
Authors: Führs Hendrik , Hartwig Moritz , Molina Laura Elisa Buitrago , Heintz Dimitri , Van Dorsselaer Alain , Braun Hans‐Peter , Horst Walter J.
Published: December 2007

The apoplast is known to play a predominant role in the expression of manganese (Mn) toxicity in cowpea (Vigna unguiculata L.) leaves. To unravel early Mn‐toxicity responses after 1–3 days Mn treatment also in the leaf symplast, we studied the symplastic reactions induced by Mn in two cultivars differing in Mn tolerance on a total cellular level. Comparative proteome analyses of plants exposed to low or high Mn allowed to identify proteins specifically affected by Mn, particularly in the Mn‐sensitive cowpea cultivar. These proteins are involved in CO2 fixation, stabilization of the Mn cluster of the photosystem II, pathogenesis‐response reactions and protein degradation. Chloroplastic proteins important for CO2 fixation and photosynthesis were of lower abundance upon Mn stress suggesting scavenging of metabolic energy for a specific stress response. Transcriptome analyses supported these findings, but additionally revealed an upregulation of genes involved in signal transduction only in the Mn‐sensitive cultivar. In conclusion, a coordinated interplay of apoplastic and symplastic reactions seems to be important during the Mn‐stress response in cowpea.
Proteome analysis of matrix vesicles isolated from femurs of chicken embryo
Authors: Balcerzak Marcin , Malinowska Agata , Thouverey Cyril , Sekrecka Anna , Dadlez Michal , Buchet Rene , Pikula Slawomir
Published: December 2007

Matrix vesicles (MVs) are extracellular organelles that initiate mineral formation, accumulating inorganic phosphate (Pi) and calcium leading to the formation of hydroxyapatite (HA) crystals, the main mineral component of bones. MVs are produced during bone formation, as well as during the endochondral calcification of cartilage. MVs are released into the extracellular matrix from osseous cells such as osteoblasts and hypertrophic chondrocytes. In this report, using 1‐D SDS‐PAGE, in‐gel tryptic digestion and an LC‐MS‐MS/MS protein identification protocol, we characterized the proteome of MVs isolated from chicken embryo (Gallus gallus) bones and cartilage. We identified 126 gene products, including proteins related to the extracellular matrix and ion transport, as well as enzymes, cytoskeletal, and regulatory proteins. Among the proteins recognized for the first time in MVs were aquaporin 1, annexin A1 (AnxA1), AnxA11, glycoprotein HT7, Gi protein α2, and scavenger receptor type B. The pathways for targeting the identified proteins into MVs and their particular functions in the biomineralization process are discussed. Obtaining a knowledge of the functions and roles of these proteins during embryonic mineralization is a prerequisite for the overall understanding of the initial mineral formation mechanisms.
Frontiers in glycomics: Bioinformatics and biomarkers in disease An NIH White Paper prepared from discussions by the focus groups at a workshop on the NIH campus, Bethesda MD (September 11–13, 2006)
Authors: Packer Nicolle H. , von der Lieth Claus‐Wilhelm , Aoki‐Kinoshita Kiyoko F. , Lebrilla Carlito B. , Paulson James C. , Raman Rahul , Rudd Pauline , Sasisekharan Ram , Taniguchi Naoyuki , York William S.
Published: December 2007

Key issues relating to glycomics research were discussed after the workshop entitled “Frontiers in Glycomics: Bioinformatics and Biomarkers in Disease” by two focus groups nominated by the organizers. The groups focused on two themes: (i) glycomics as the new frontier for the discovery of biomarkers of disease and (ii) requirements for the development of informatics for glycomics and glycobiology. The mandate of the focus groups was to build consensus on these issues and develop a summary of findings and recommendations for presentation to the NIH and the greater scientific community. A list of scientific priorities was developed, presented, and discussed at the workshops. Additional suggestions were solicited from workshop participants and collected using the workshop mailing list. The results are summarized in this White Paper, authored by the co‐chairs of the focus groups.
Comparative effect of phthalazinone units in sulfonated poly(arylene ether ether ketone ketone) copolymers as proton exchange membrane materials
Authors: Kim Dae Sik , Guiver Michael D.
Published: December 2007

A new series of aromatic poly(arylene ether ether ketone ketone) copolymers containing pendant sulfonic acid groups (SPAEEKK‐D) were synthesized from commercially available monomers 1,3‐bis(4‐fluorobenzoyl)‐benzene, sodium 6,7‐dihydroxy‐2‐naphthalenesulfonate, and 4‐(4‐hydroxyphenyl)‐2,3‐phthalazin‐1‐one (DHPZ). Structure–property relationships of the phthalazinone SPAEEKK‐D series poly(arylene ether ether ketone ketone) copolymer were compared with copolymers SPAEEKK‐B and SPAEEKK‐H containing different diols such as 4,4′‐biphenol and hydroquinone, respectively, prepared in our earlier work. Ion exchange capacity (IECw, weight‐based; IECv, volume‐based), thermal stabilities, swelling, proton and methanol transport properties of the membranes were investigated in relation to their structures and compared with those of perfluorinated ionomer (Nafion 117). The SPAEEKK‐D membrane incorporating the phthalazinone monomer DHPZ showed relatively lower water uptake and methanol permeability compared with earlier SPAEEKK‐B and SPAEEKK‐H membranes incorporating biphenol and hydroquinone monomers, respectively. Inclusion of phthalazinone in the SPAEEKK‐D copolymers led to lower water absorption, enabling increased proton exchange concentrations in the hydrated polymer matrix that resulted in more desirable membrane properties for future direct methanol fuel cell applications. The SPAEEKK‐D membranes also showed improved mechanical and thermal properties and oxidative stability compared with the earlier SPAEEKK‐B and ‐H membranes. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 989–1002, 2008
A model for facilitating curriculum development in higher education: A faculty‐driven, data‐informed, and educational developer–supported approach
Authors: Wolf, Peter
Published: December 2007

This chapter explores the processes that have been developed and refined by educational developers in Teaching Support Services at the University of Guelph to support faculty‐driven curriculum assessment and development initiatives.
Assisting curriculum change through departmental initiatives
Authors: Roy Dale , Borin Paola , Kustra Erika
Published: December 2007

This chapter describes the assumptions and principles for good practice based on case studies at a research‐intensive university in which several departments introduced curriculum change through a novel departmental grants program.
Continuous curriculum assessment and improvement: A case study
Authors: Hill Art
Published: December 2007

This chapter describes the simple sustainable assessment protocols followed in food science at the University of Guelph to help ensure a continuously improving curriculum that satisfies the pedagogical prescriptions of the Institute of Food Technology, the learning objectives of the university, and learning outcomes of other stakeholders, including employers, students, and faculty.
REVISIONARY INTUITIONISM
Authors: Huemer Michael
Published: December 2007

I discuss four kinds of challenges to the reliability of ethical intuitions. Ethical intuitions have been impugned for being incoherent with each other, for being unduly influenced by culture, for being unduly influenced by biological instincts, and for being unduly influenced by personal interests and emotions. I argue that, rather than giving up on the possibility of ethical knowledge through intuition, intuitionists should use the skeptical challenges to help identify which intuitions are most likely to be reliable, and which are instead likely to be biased or otherwise distorted. In many cases, abstract, formal intuitions about value and obligation prove to be least susceptible to skeptical attack and for that reason should be given preference in our ethical reasoning over most intuitions about concrete situations. In place of the common sense morality with which intuitionism has traditionally been allied, my approach is likely to generate a highly revisionary normative ethics.