bluuebunny/crossref_metadata_2025_split huggingface dataset:
Negative electrospray ionization low‐energy tandem mass spectrometry of hydroxylated fatty acids: a mechanistic study
Authors: Moe Morten K. , Strøm Morten B. , Jensen Einar , Claeys Magda 
Published: July 2004

AbstractRecently, we reported that by converting olefinic fatty acids to their saturated vicinally 1,2‐di‐hydroxylated derivatives, abundant ions indicative for hydroxyl group locations are produced by negative electrospray ionization low‐energy tandem mass spectrometry, allowing the assignment of the olefinic site in the native fatty acid. In this report the mechanisms whereby the characteristic ions are produced are investigated. The mono‐hydroxylated fatty acid, 12‐hydroxyoctadecanoic acid, served as a model for the more complex 12,13‐dihydroxyoctadecanoic acid, and fragmentation mechanisms accounting for the most abundant product ions generated from their deprotonated molecules are proposed. In general, three different mechanisms are proposed to operate in the formation of the observed product ions: (i) step‐wise charge‐remote homolytic cleavages, (ii) step‐wise charge‐proximate homolytic cleavages, and (iii) concerted charge‐directed rearrangement reactions involving bond formation(s) and heterolytic cleavages. Support for the proposed mechanisms was achieved by investigating the deuterium‐ and oxygen‐18‐labeled isotopomers of both compounds. Copyright © 2004 John Wiley & Sons, Ltd.
High‐pressure ion trap mass spectrometry
Authors: Whitten William B. , Reilly Peter T. A. , Ramsey J. Michael 
Published: July 2004

AbstractThe effects of buffer gas pressure on ion trap stability, mass resolution/calibration, and choice of mass scanning are described. Pressure effects were treated phenomenologically by adding a drag term to the ion equations of motion. The resulting collisional damping enlarges the mass‐dependent stability region but reduces the region in which mass‐selective resonance ejection can be performed. The pressure effects can be reduced by increasing the frequency of the alternating quadrupole field. Copyright © 2004 John Wiley & Sons, Ltd.
Starch Derivatives of High Degree of Functionalization. 7. Preparation of Cationic 2‐Hydroxypropyltrimethylammonium Chloride Starches
Authors: Heinze Thomas , Haack Vera , Rensing Stephan 
Published: July 2004

AbstractWater‐soluble starch derivatives containing quarternary ammonium groups of high degree of substitution are prepared by reacting starch with 2,3‐epoxypropyltrimethylammonium chloride in different reaction media. The reaction was carried out in aqueous sodium hydroxide under dissolution of the product, in dimethyl sulfoxide homogeneously, and completely heterogeneously in ethanol/water. The DS values of up to 1.1 in an one‐step synthesis of the samples can be controlled by adjusting the molar ratio of cationization agent to anhydroglucose unit and are only slightly dependent on the amylose content of the starting starch material. A two‐step reaction yields products of a DS of up to 1.5. The structure of the cationic starch derivatives was confirmed by means of elemental analysis, FTIR‐ and NMR spectroscopy as well as GC‐MS.
Film Properties of Hydroxypropyl Starch
Authors: Vorwerg Waltraud , Dijksterhuis Jan , Borghuis Johannes , Radosta Sylvia , Kröger Anja 
Published: July 2004

AbstractThe present study describes the preparation of low‐substituted hydroxypropyl (HP) starches and investigation of their suitability for the development of flexible, highly transparent cast films. Changes in molecular composition due to processing conditions were identified by determining molar mass distribution. Molecular characterisation was performed both by static light scattering (SLS) and size‐exclusion chromatography with multi‐angle laser light scattering (SEC‐MALLS) detection. The weight‐average molar mass, mean square radius of gyration, second virial coefficient, and molar mass distribution were determined. Rheological characterisation of concentrated aqueous solutions included a study of flow behaviour as a function of shear rate and oscillatory measurement of viscoelastic properties. Significant differences in rheological properties due to hydroxypropylation conditions were established. Mechanical testing was carried out by measuring tensile strength and elongation and determining the elastic modulus. The tensile strength of cast films based on hydroxypropyl starches was 40–50 MPa. Elongation values were dependent on the type of starch, use of plasticiser and storage conditions.
Structure Analysis of Carboxymethyl Starch by Capillary Electrophoresis and Enzymic Degradation
Authors: Tüting Wiebke , Albrecht Gerald , Volkert Bert , Mischnick Petra 
Published: July 2004

AbstractCarboxymethyl starches (CMS) with a degree of substitution (DS) in the range of 1.2 to 1.5 were analysed by capillary electrophoresis (CE) after hydrolysis and reductive amination in a borate buffer. The monomer composition determined was compared to data calculated by the statistical models of Spurlin and Reuben. In addi­tion, the starch derivatives were exhaustively degraded by α‐amylase and amylo­glucosidase and the amount of glucose liberated was determined. Results were discussed with regard to derivatisation conditions and properties of the carboxymethyl starches.
Highly Substituted Carboxymethyl Starch
Authors: Volkert Bert , Loth Fritz , Lazik Waldemar , Engelhardt Jürgen 
Published: July 2004

AbstractCarboxymethyl starches (CMS) with a degree of substitution (DS) in the range of 0.5 to 1.5 and reagent yields about 70% were synthesised under heterogeneous reaction conditions. Starting from a standard procedure for manufacturing low substituted CMS the molar ratios of the reagents were increased. Under these conditions starch particles agglomerated during the reaction and the stirrer stopped. The reaction conditions (pulp density, addition of dispersing and water binding agents, pressure, sequence of reagents addition, reaction time, temperature, starch variety, etc.) were varied to find the best process conditions for optimum reaction efficiencies and product properties. If an amylose‐free starch, e.g. waxy corn starch is used as starting material, the obtained products are completely soluble in water to form a clear solution. The products are good viscosity regulators. Using a 2% aqueous solution a wide range of viscosity (1–90 000 mPa s) can be adjusted. The calcium‐binding capacity and the biodegradability of the products were investigated.
L x‐ray fluorescence cross‐sections of heavy elements in the atomic region 57 ≤ Z ≤ 71 excited by 17.78 keV photons
Authors: Salah Wa'el 
Published: July 2004

AbstractL x‐ray fluorescence cross‐sections (σLα, σLβ, and σLγ) were measured with an accuracy of 6% (except for the Lγ x‐ray line around 8%) for La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb and Lu at an excitation energy of 17.78 keV. Relative intensities IKβ/IKα and ILγ/ILα were also measured for the same elements. The measured cross‐sections were compared with experimental and theoretical values. Measurements of the emitted x‐rays were performed using an Si(Li) detector. Copyright © 2004 John Wiley & Sons, Ltd.
Work Practices and Histopathological Changes in the Tenosynovium in Carpal Tunnel Syndrome in Men
Authors: PICKERING S. A. W. , STEVENS A. , DAVIS T. R. C. 
Published: July 2004

The aim of this prospective study was to assess whether the fibrous thickening of the carpal tunnel tenosynovium is influenced by working practices. We did this by investigating 50 men (58 hands) with idiopathic carpal tunnel syndrome, who were undergoing carpal tunnel decompression. Occupational history, including vibration tool exposure, and presence of callosities and/or ingrained dirt on hands was recorded at the time of surgery. The flexor tenosynovium was biopsied, and assessed histologically by an observer blinded to occupational history. Occupational group, age, weight and smoking showed no significant association with fibrous tenosynovial thickening. There was also no significant association between fibrous tenosynovial thickening and the presence of hand callosities/in-grained dirt or regular use of vibration tools. Thus no association was found between heavy occupational hand usage and the development of fibrous tenosynovial thickening around tendons within the carpal tunnel.
Treatment of End-Neuromas, Neuromas-in-Continuity and Scarred Nerves of the Digits by Proximal Relocation
Authors: HAZARI A. , ELLIOT D. 
Published: July 2004

This paper reports the results of treatment by proximal relocation of 104 painful nerves in 57 digits in 48 patients. These included 86 digital nerves and 18 terminal branches of the superficial radial nerve and the dorsal branch of the ulnar nerve. Eighty-three were end-neuromas and 14 were neuromas-in-continuity, of which nine followed nerve repair and five occurred following a closed crush injury. Seven were painful as a result of tethering in scarred tissue. Eighty nerves (77%) required a single relocation and 24 (23%) required more than one operation. Ninety-eight per cent of nerve relocations achieved complete pain relief at the primary site. One patient had mild pain on pressure at the primary site after relocation of two nerves from this site. Over 90% of the nerves had no spontaneous pain, pain on movement or hypersensitivity of the overlying skin at the final site of relocation. However, the incidence of mild or no pain on direct pressure at the site of nerve relocation was lower at 83% as relocated nerves, although traumatized less often at the sites chosen for relocation, can still be painful on direct pressure.
ON COMPUTING THE NON-ABELIAN TENSOR SQUARES OF THE FREE 2-ENGEL GROUPS
Authors: Blyth Russell D. , Morse Robert Fitzgerald , Redden Joanne L. 
Published: July 2004

AbstractIn this paper we compute the non-abelian tensor square for the free 2-Engel group of rank $n>3$. The non-abelian tensor square for this group is a direct product of a free abelian group and a nilpotent group of class 2 whose derived subgroup has exponent 3. We also compute the non-abelian tensor square for one of the group’s finite homomorphic images, namely, the Burnside group of rank $n$ and exponent 3.AMS 2000 Mathematics subject classification: Primary 20F05; 20F45. Secondary 20F18
LEFT ANNIHILATORS CHARACTERIZED BY DIFFERENTIAL IDENTITIES
Authors: Lee Tsiu-Kwen , Pan Ching-Yueh 
Published: July 2004

AbstractLet $R$ be a semiprime ring with $U_{\trm{s}}$ its maximal symmetric ring of quotients and let $\rho_1$ and $\rho_2$ be two right ideals of $R$. We show that $\ell_R(\rho_1)=\ell_R(\rho_2)$ if and only if $\rho_1$ and $\rho_2$ satisfy the same differential identities with coefficients in $U_{\trm{s}}$, where $\ell_R(\rho_i)$ denotes the left annihilator of $\rho_i$ in $R$. This gives a generalization of several previous results in this area.AMS 2000 Mathematics subject classification: Primary 6R50. Secondary 16N60
DISCRETE APPROXIMATION OF NON-COMPACT OPERATORS DESCRIBING CONTINUUM-OF-ALLELES MODELS
Authors: Redner Oliver 
Published: July 2004

AbstractWe consider the eigenvalue equation for the largest eigenvalue of certain kinds of non-compact linear operators given as the sum of a multiplication and a kernel operator. It is shown that, under moderate conditions, such operators can be approximated arbitrarily well by operators of finite rank, which constitutes a discretization procedure. For this purpose, two standard methods of approximation theory, the Nyström and the Galerkin method, are generalized. The operators considered describe models for mutation and selection of an infinitely large population of individuals that are labelled by real numbers, commonly called continuum-of-alleles models.AMS 2000 Mathematics subject classification: Primary 47A58; 45C05. Secondary 47B34
INVERSE FACTORIAL-SERIES SOLUTIONS OF DIFFERENCE EQUATIONS
Authors: Olde Daalhuis A. B. 
Published: July 2004

AbstractWe obtain inverse factorial-series solutions of second-order linear difference equations with a singularity of rank one at infinity. It is shown that the Borel plane of these series is relatively simple, and that in certain cases the asymptotic expansions incorporate simple resurgence properties. Two examples are included. The second example is the large $a$ asymptotics of the hypergeometric function ${}_2F_1(a,b;c;x)$.AMS 2000 Mathematics subject classification: Primary 34E05; 39A11. Secondary 33C05
ESTIMATES FOR MAHLER’S MEASURE OF A LINEAR FORM
Authors: Rodriguez-Villegas Fernando , Toledano Ricardo , Vaaler Jeffrey D. 
Published: July 2004

AbstractLet $L_{\bm{a}}(\bm{z})=a_1z_1+a_2z_2+\cdots+a_Nz_N$ be a linear form in $N$ complex variables $z_1,z_2,\dots,z_N$ with non-zero coefficients. We establish several estimates for the logarithmic Mahler measure of $L_{\bm{a}}$. In general, we show that the logarithmic Mahler measure of $L_{\bm{a}}(\bm{z})$ and the logarithm of the norm of $\bm{a}$ differ by a bounded amount that is independent of $N$. We prove a further estimate which is useful for making an approximate numerical evaluation of the logarithmic Mahler measure.AMS 2000 Mathematics subject classification: Primary 11C08; 11Y35; 26D15
INTERNAL q-HOMOLOGY OF CROSSED MODULES
Authors: Ladra Manuel , Vieites Ana M. 
Published: July 2004

AbstractFor $q$ a non-negative integer, we introduce the internal $q$-homology of crossed modules and we obtain in the case $q=0$ the homology of crossed modules. In the particular case of considering a group as a crossed module we obtain that its internal $q$-homology is the homology of the group with coefficients in the ring of the integers modulo $q$.The second internal $q$-homology of crossed modules coincides with the invariant introduced by Grandjeán and López, that is, the kernel of the universal $q$-central extension. Finally, we relate the internal $q$-homology of a crossed module to the homology of its classifying space with coefficients in the ring of the integers modulo $q$.AMS 2000 Mathematics subject classification: Primary 18G50; 20J05. Secondary 18G30
The ophiolite-related Mersin Melange, southern Turkey: its role in the tectonic–sedimentary setting of Tethys in the Eastern Mediterranean region
Authors: PARLAK OSMAN , ROBERTSON ALASTAIR 
Published: July 2004

The Mersin Melange underlies the intact Mersin Ophiolite and its metamorphic sole to the south of the Mesozoic Tauride Carbonate Platform in southern Turkey. The Melange varies from chaotic melange to broken formation, in which some stratigraphic continuity can be recognized. Based on study of the broken formation, four lithological associations are recognized: (1) shallow-water platform association, dominated by Upper Palaeozoic–Lower Cretaceous neritic carbonates; (2) rift-related volcanogenic–terrigenous–pelagic association, mainly Upper Triassic andesitic–acidic volcanogenic rocks, siliciclastic gravity flows, basinal carbonates and radiolarites; (3) within-plate-type basalt–radiolarite–pelagic limestone association, interpreted as Upper Jurassic–Lower Cretaceous seamounts with associated radiolarian sediments and Upper Cretaceous pelagic carbonates; (4) ophiolite-derived association, including fragments of the Upper Cretaceous Mersin Ophiolite and its metamorphic sole. Locally, the ophiolitic melange includes granite that yielded a K/Ar radiometric age of 375.7±10.5 Ma (Late Devonian). This granite appears to be subduction influenced based on ‘immobile’ element composition.The Mersin Melange documents the following history: (1) Triassic rifting of the Tauride continent; (2) Jurassic–Cretaceous passive margin subsidence; (3) oceanic seamount genesis; (4) Cretaceous supra-subduction zone ophiolite genesis; (5) Late Cretaceous intra-oceanic convergence-metamorphic sole formation, and (6) latest Cretaceous emplacement onto the Tauride microcontinent and related backthrusting.Regional comparisons show that the restored Mersin Melange is similar to the Beyşehir–Hoyran Nappes further northwest and a northerly origin best fits the regional geological picture. These remnants of a North-Neotethys (Inner Tauride Ocean) were formed and emplaced to the north of the Tauride Carbonate Platform. They are dissimilar to melanges and related units in northern Syria, western Cyprus and southwestern Turkey, which are interpreted as remnants of a South-Neotethys. Early high-temperature ductile transport lineations within amphibolites of the metamorphic sole of the Mersin ophiolite are generally orientated E–W, possibly resulting from vertical-axis rotation of the ophiolite while still in an oceanic setting. By contrast, the commonly northward-facing later stage brittle structures are explained by backthrusting of the ophiolite and melange related to exhumation of the partially subducted northern leading edge of the Tauride continent.
Systematic review of the role of gender as a health determinant of hospitalization for depression
Authors: Savoie Isabelle , Morettin Denise , Green Carolyn J. , Kazanjian Arminée 
Published: July 2004

Objectives:To conduct a systematic review of selected health determinants, including gender, and their impact on hospitalization rates for depression. Depression includes both depressive and bipolar disorders. Selected health determinants were gender, age, sex, family structure, education, and socioeconomic status.Methods:Systematic search of conventional and fugitive literature sources. All reports of primary data, systematic reviews, and meta-analysis of primary data were included if they focused on hospitalization for depression and reported data by one or more of the selected health determinants. Two researchers independently evaluated each citation for inclusion and extracted data from the included studies.Results:There is an important underreporting of health determinants data in studies of hospitalization for depression. No studies examined the role of gender. Age and sex were reported in 83 percent and 80 percent of the 110 included studies. Women showed a higher rate of hospitalization for depression than men (p<.05). Age and diagnosis had different effects in men and women. Adult women were significantly more likely than men to report a depressive disorder, whereas men were more likely to report a bipolar disorder (p<.05). Little can be concluded on the other health determinants.Conclusions:The importance of reporting hospitalization data and conducting hospital utilization analysis by sex and health determinants, including gender, must be emphasized.
Eliciting women's preferences in health care: A review of the literature
Authors: Sampietro-Colom Laura , Phillips Victoria L. , Hutchinson Angela B. 
Published: July 2004

Objectives: The increasing availability of information about health care suggests an expanding role for consumers to exercise their preferences in health-care decision-making. Numerous methods are available to assess consumer preferences in health care. We conducted a systematic review to characterize the study of women's preferences about health careMethods: A MEDLINE search from 1965 to July 1999 was conducted as well as hand searches of the itshape Medical Decision Making Journal (1981–1999) and references from retrieved articles. Only original articles on women's health issues were selected. Information on thirty-one variables related to study characteristics and preferences were extracted by two independent investigators. A third investigator resolved disagreements. Qualitative and quantitative analyses were conducted to synthesize the data.Results: Four hundred eighty-three studies were identified in the initial search. Seventy articles were selected for review based on title, abstract, and inclusion criteria. There was an increase in published articles and number of methods used to elicit preferences. White women were studied more than black women (p<.001). Preferences were mainly studied in outpatient settings (p<.005) and in the United States, United Kingdom, and Canada (83 percent). Preferences related to participation in decision-making were the most common (21 percent). Only 4 percent of the studies were performed to inform the debate for public policy questions. Willingness to pay was the method most used (11 percent), followed by category scaling (10 percent), rating scale (9 percent), standard-gamble (6 percent). Preferences for individual particular (opposed to sequential and health states) outcomes (68 percent), different treatments/tests (47 percent), and related to a treatment episode (31 percent) were addressed. Information regarding diseases, conditions, or procedures was given in 57 percent of studies. Information provided was mainly written (37 percent) and included positive and negative potential outcomes (67 percent). There is no relationship between the method or tool used for delivery information and the choice performed.Conclusions: The literature on preferences in women's health care is limited to a fairly homogeneous population (white women from the United States, United Kingdom, and Canada). Additionally, use of utility-based measures to capture preferences has decreased over time while others methods (e.g., time trade-off [TTO], contingent valuation) have increased. Women's preferences are not necessarily uniform even when asked similar questions using similar tools. Little information on women's preferences exists to inform policy-makers about women's health care.
Informing, advising, or persuading? An assessment of bone mineral density testing information from consumer health websites
Authors: Green Carolyn J. , Kazanjian Arminée , Helmer Diane 
Published: July 2004

Greater access to web-based information on health-care interventions might result in greater participation by patients in care and self-care decisions, but only improve health outcomes if the indicated actions produce the intended benefits. Unbiased research on benefits and harms of health information can provide a basis for evidence-based patient information systems.Objectives:To evaluate the quality of the information content on bone-mineral density (BMD) testing posted on consumer health websites (CHWS).Methods:Five popular engines (Yahoo, MSN, AOL, Lycos, and Go.com) were used to search for patient information on bone densitometry. The fifteen websites that supplied relevant content and were identified by three of the five search engines were selected in order of popularity of the search engine and primacy of placement. Six BMD reports from health technology assessment (HTA) organizations were used as a standard of scientific quality. These were identified from the HTA Database at York University United Kingdom and published between 1996 and 2001. Content was extracted from both document types, and these sets were compared independently by two reviewers.Results:The majority of CHWS identified by popular search engines do not disclose the limited capacity of BMD to discriminate between low-risk individuals and those who will suffer future fractures. CHWS generally present BMD testing as quick, painless, noninvasive, and as being recommended, based on risk factors that are widespread among the general public. BMD testing information is prominently paired on CHWS sites with information on osteoporosis, with an emphasis on “silent disease” and the devastating consequences of advanced disease. Sponsors of CHWS sites are frequently either providers of BMD testing or companion drugs, and consequently in a position of conflict of interest with regard to decisions to undergo BMD testing. HTA organizations have no documented conflict of interest, nor do they invoke emotional arguments. Their approach is to emphasize the effects of testing on populations, on the basis of referenced research findings.Conclusions:Content analysis demonstrates the omissions and divergence of information on BMD testing available to consumers on the Internet, as compared with HTA reports. The content of HTA reports has undergone rigorous systematic and peer review; therefore, their findings may be useful to consumers. This information is not generally accessible to patients using the most popular Internet search engines. Inaccurate and incomplete information may cause harm by deflecting patients from optimal decisions.