bluuebunny/crossref_metadata_2025 huggingface dataset:
Microhydrodynamic analysis of nanogrinding in stirred media mills
Authors: Eskin D. , Zhupanska O. , Hamey R. , Moudgil B. , Scarlett B.
Published: March 2005

The dynamics of the milling media in a turbulent flow is considered. The mean velocity of the milling beads is calculated on the assumption that the power spent on stirring is transferred into the energy of turbulent eddies. The energy spent on stirring dissipates as a result of media–liquid viscous friction, lubrication, and by inelastic collisions of the beads with each other. The maximum force at which the milling beads can compress particles between them is calculated by the Hertzian theory of elastic impact. The frequency of compressions for a single particle is evaluated by probabilistic analysis. A criterion of milling efficiency, based on calculating the energy spent on the plastic particle deformation, is proposed. A numerical study of the milling bead dynamics and their interactions with the particles in the mixing tank is performed. The numerical results are in qualitative agreement with the experimental data. Both the numerical and experimental analyses show that, from the perspective of hydrodynamics, an optimization of stirred media mills can be achieved by choosing the optimum size and concentration of the milling media. © 2005 American Institute of Chemical Engineers AIChE J, 2005
PBM and activated sludge flocculation: From experimental data to calibrated model
Authors: Nopens I. , Koegst T. , Mahieu K. , Vanrolleghem P. A.
Published: March 2005

A new comprehensive calibration methodology for a population balance model (PBM) is presented using experimental size distribution data obtained on‐line during flocculation tests. It was found that the moving‐pivot discretization technique should be used to accurately solve the PBM. A new methodology for grid transformation and volume to number transformation, based on the sludge concentration and the densities of liquid, solids, and flocs, is presented. Model fits were performed on four different fitting variables. Volume‐based fitting (vol % and D[4, 3]) tends to fit the middle part of both the vol % and number distribution better than the tails of smaller and larger particle sizes. Severe underpredictions (up to a factor of 30) of the lower‐size classes are observed at steady state. Number‐based fitting [(weighted) number distribution] tends to fit the small‐size classes better, but still underpredicts them by a factor of 2 at steady state. © 2005 American Institute of Chemical Engineers AIChE J, 2005
Statistical modelling of functional data
Authors: Besse Philippe C. , Cardot Hervé , Faivre Robert , Goulard Michel
Published: March 2005

This paper presents some statistical models and estimation procedures when the explanatory variables are functions. We put the stress on the fact that regularization techniques are needed in order to get stable and reliable estimations. Then, an application in remote sensing in presented. It shows the potential of these kind of models to handle real life problems. Copyright © 2005 John Wiley & Sons, Ltd.
Outpatient coronary angioplasty: Feasible and safe
Authors: Slagboom Ton , Kiemeneij Ferdinand , Laarman Gert Jan , van der Wieken Ron
Published: March 2005

This study tested the safety and feasibility of coronary angioplasty on an outpatient basis. The purpose of this approach includes cost‐effectiveness and patient comfort. Six hundred forty‐four patients were randomized to either transradial or transfemoral PTCA using 6 Fr equipment. Patients were triaged to outpatient management based on a predefined set of predictors of an adverse outcome in the first 24 hr after initially successful coronary angioplasty. Three hundred seventy‐five patients (58%) were discharged 4–6 hr after PTCA; 42% stayed in hospital overnight. In the outpatient group, one adverse event occurred (subacute stent thrombosis 7 hr postdischarge, nonfatal myocardial infarction). There were no major vascular complications. In the hospital group, 19 patients (7%) sustained an adverse cardiac even in the first 24 hr; 1 patient died. Patients treated via the femoral route had more (minor) bleeding complications (19 patients; 6%); in 17 of these, this was the sole reason that discharge was delayed. PTCA on an outpatient basis, performed via the radial or the femoral artery with low‐profile equipment, is safe and feasible in a considerable part of a routine PTCA population. A larger proportion of transradial patients can be discharged due to a reduction in (minor) bleeding complications. Catheter Cardiovasc Interv 2005;64:421–427. © 2005 Wiley‐Liss, Inc.
Syntheses and Properties of Metal‐Centered Mixed‐Valent [NEt4]{MnII⊂[MnII3MnIII3Cl6(L)6]} Manganese Wheels
Authors: Saalfrank Rolf W. , Nakajima Takayuki , Mooren Nicolai , Scheurer Andreas , Maid Harald , Hampel Frank , Trieflinger Christian , Daub Jörg
Published: March 2005

Upon reaction of N‐substituted diethanolamines H2L2–4 (4, 6, 7) with cesium carbonate and bis(tetraethylammonium) tetrachloromanganate(II) in acetonitrile in the presence of air, the metal‐centered mixed‐valent manganese wheels [NEt4]{MnII⊂[MnII3MnIII3Cl6(L2–4)6]} (8–10) were generated. X‐ray crystallographic structure analyses revealed, that 8–10 are principally isostructural and consist of an alternating ring of three MnII and three MnIII ions, centered by an additional MnII ion. The cyclic voltammograms of 8 and 10 displayed three quasi‐reversible oxidation processes, which are attributed to the subsequent one electron‐oxidations of the three peripheral MnII ions to MnIII. Oxidation of the central MnII ion is not observed within the applied potential. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Ordered Meso‐ and Macroporous Binary and Mixed Metal Oxides
Authors: Carreon Moises A. , Guliants Vadim V.
Published: March 2005

The caption of Figure 8 on page 32 of the original article[1] was reporduced incompletely; the correct caption should read as follows: Figure 8. Nitrogen adsorption−desorption isotherms and BJH pore‐size distribution plot (inset) for mesoporous niobium oxide (L. Yuan, V. V. Guliants, unpublished data).
Effect of argon‐plasma treatment on proliferation of human‐skin–derived fibroblast on chitosan membrane in vitro
Authors: Zhu Xiao , Chian Kerm Sin , Chan‐Park Mary Bee Eng , Lee Seng Teik
Published: March 2005

Chitosan is not only a nontoxic, biocompatible, and biodegradable polymer, but has also a chemical structure similar to glycosaminoglycans (GAGs), which promote scarless wound healing of skin. In this study, chitosan membranes were treated with argon plasma to improve their surface hydrophilicity. The results showed that the water contact angles of these surface‐treated membranes were significantly reduced from 60.76 to 11.57°. The total surface energy was increased from 41.06 to 67.31 mJ/m2, with 60–86.95% improvement in the gamma‐negative component and a 20% difference in the nonpolar component. Argon‐plasma–treated chitosan membranes exhibited excellent attachment, migration, and proliferation of the human‐skin–derived fibroblasts (hSFs) compared to the untreated ones. It was found that the duration of argon‐plasma treatment influenced the cell proliferation, and the optical densities in MTT assay were enhanced. Argon‐plasma treatment improved the surface hydrophilicity of chitosan membranes and promoted the attachment and proliferation of hSFs. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res 73A: 264–274, 2005
Photocatalytic and photoelectrochemical performance of crystallized titanium dioxide sol with neodymium ion modification
Authors: Xie Yibing , Yuan Chunwei
Published: March 2005

Titanium dioxide was modified with neodymium metal ion by a wet‐chemical coprecipitation–peptization technique under low temperature to produce crystallized sol catalyst (Nd3+TiO2). Crystal structure was characterized by X‐ray diffraction measurement. Sol particle size was studied by means of particle size distribution measurement. Surface hydroxyl groups were determined using Fourier transform infrared spectroscopy. Photocatalytic reactivity of sol photocatalysts was investigated under ultraviolet and visible light irradiation. Photodegradation and photomineralization under ultraviolet and visible light excitation were studied in the TiO2 and Nd3+TiO2 hydrosol reaction system. A photocurrent–time spectrum was also applied to characterize the electron‐transferring efficiency in the process of self‐sensitization and dye‐sensitization photocatalysis reactions. As an application approach of sol catalyst, Nd3+TiO2 sol was coated on a diffusing optical fibers bundle and the photocatalytic reaction was investigated in the immobilization fiber reactor. Copyright © 2005 Society of Chemical Industry
Liquid–liquid extraction of cadmium(II) by Cyanex 923 and its application to a solid‐supported liquid membrane system
Authors: Rodríguez Ana María , Gómez‐Límón Dulce , Alguacil Francisco José
Published: March 2005

The extraction of cadmium(II) by Cyanex 923 (a mixture of alkylphosphine oxides) in Solvesso 100 from hydrochloric acid solution has been investigated. The extraction reaction is exothermic. The numerical analysis of metal distribution data suggests the formation of CdCl2.2L, HCdCl3.2L and H2CdCl4.2L (L = ligand) in the organic phase. The results obtained for cadmium(II) distribution have been implemented in a solid‐supported liquid membrane system. The influences of feed phase stirring speed (400–1400 min−1), membrane composition (carrier concentration: 0.06–1 mol dm−3) and metal concentration (0.01–0.08 g dm−3) on cadmium transport have been investigated. Copyright © 2005 Society of Chemical Industry
Activation of extracellular signal‐regulated kinase 5 may play a neuroprotective role in hippocampal CA3/DG region after cerebral ischemia
Authors: Wang Rui‐Min , Zhang Quan‐Guang , Li Chun‐Hong , Zhang Guang‐Yi
Published: March 2005

Extracellular signal‐regulated kinase 5 (ERK5), the newest member of the mitogen‐activated protein (MAP) kinase family of proteins, is widely expressed in many tissues, including the brain. Here we investigated the activation and subcellular localization of ERK5 by immunoblotting and immunohistochemistry as well as its potential role following cerebral ischemia in rat hippocampus. Transient cerebral ischemia was induced by the four‐vessel occlusion method in Sprague‐Dawley rats. Our results first indicated that the strongly activated ERK5 immunoreactivity was seen in the CA3/DG region but not in the CA1 pyramidal cell of rat hippocampus following reperfusion. In cytosol extracts, ERK5 activation was rapidly increased, with a peak at 30 min, and then gradually decreased to basal level at 3 days of reperfusion. In nucleus extracts, both phospho‐ERK5 and its protein expression were persistently enhanced during the later reperfusion period (from 6 hr to 3 days). To elucidate further the possible role of ERK5 activation and subcellular localization in ischemic insult, rats were intraperitoneally administrated with nifedipine (ND) and dextromethorphan (DM), inhibitors of two types of calcium channels, 20 min prior to ischemia. Our findings showed that ND or DM significantly reduced activated ERK5 immunoreactivity in the nucleus and that most of the CA3/DG neurons were lost 3 days later. Most importantly, intracerebroventricular infusion of ERK5 antisense oligonucleotides (AS; every 24 hr for 3 days before ischemia), but not sense oligonucleotides or vehicle, not only markedly decreased the level of ERK5 and p‐ERK5 but also largely caused neuronal loss in the CA3/DG region at 3 days of reperfusion. Taken together, the results strongly suggest that ERK5 was selectively activated in the hippocampal CA3/DG region and subsequently translocated from the cytosol to the nucleus through activation of N‐methyl‐D‐aspartate receptor and L‐type voltage‐gated calcium channel, which might act as an important survival signal in ischemia‐induced neuronal cell damage of the CA3/DG region. © 2005 Wiley‐Liss, Inc.
Temporal and spatial distribution of growth‐associated molecules and astroglial cells in the rat corticospinal tract during development
Authors: Hsu Jung‐Yu C. , Stein Stuart A. , Xu Xiao‐Ming
Published: March 2005

To understand better the role of growth‐promoting and ‐inhibiting molecules in the development of the corticospinal tract (CST), temporospatial expression of embryonic neural cell adhesion molecule (E‐NCAM), growth‐associated protein‐43 (GAP‐43), and chondroitin sulfate proteoglycan (CSPG) was studied in developing rats. Transverse sections of the seventh cervical (C7), seventh thoracic (T7), and fourth lumbar (L4) segments were examined at postnatal days (P) 2, 6, 10, 14, and 28. The highest E‐NCAM immunoreactivity appeared at the C7 level on P2 and shifted caudally to the T7 on P6 and L4 on P10, which correlated closely with the time course of CST development. The peak expression of GAP‐43 emerged at C7 on P2 and shifted to the T7 and L4 levels at a relatively lagging pace compared with that of E‐NCAM. Conversely, a transient reduction in CSPG immunoreactivity was found within the CST at the C7 level on P2, T7 level on P6, and L4 level on P10, corresponding well with the arrival of CST‐leading axons at these levels. Interestingly, higher levels of CSPG were found to surround the growing CST, suggesting a repulsive environment that channels the growth of CST. Moreover, a transition from immature to mature astrocytes in a rostrocaudal direction during CST development was evidenced by anti‐vimentin and anti‐glial fibrillary acidic protein (GFAP) immunostaining, suggesting a guidance role of immature astroglia in axonal outgrowth. Our study thus demonstrated dynamic changes of multiple growth‐related molecules and astroglial environment that contribute to postnatal development of the CST. © 2005 Wiley‐Liss, Inc.
Ultrafast synthesis of poly(methyl acrylate) and poly(methyl acrylate)‐b‐poly(vinyl chloride)‐b‐poly(methyl acrylate) by the Cu(0)/tris(2‐dimethylaminoethyl)amine‐catalyzed living radical polymerization and block copolymerization of methyl acrylate initiated with 1,1‐chloroiodoethane and α,ω‐Di(iodo)poly(vinyl chloride) in dimethyl sulfoxide
Authors: Percec Virgil , Guliashvili Tamaz , Popov Anatoliy V.
Published: March 2005

ABA block copolymers containing poly(methyl acrylate) (PMA) as the A segment and poly(vinyl chloride) (PVC) as the B segment (PMA‐b‐PVC‐b‐PMA) were synthesized by the Cu(0)/tris(2‐dimethylaminoethyl)amine (Me6‐TREN)‐catalyzed living radical block copolymerization of methyl acrylate (MA) initiated with α,ω‐di(iodo)poly(vinyl chloride) [α,ω‐di(iodo)PVC] in dimethyl sulfoxide (DMSO) at 90, 50, and 25 °C. 1,1‐Chloroiodoethane, a model compound for the chain ends of the α,ω‐di(iodo)PVC macroinitiator, was used as an initiator for the Cu(0)/Me6‐TREN‐catalyzed living radical polymerization of MA in DMSO at 70, 50, and 25 °C. Ultrafast block copolymerization and living radical polymerization methods for MA and other acrylates were discovered. These ultrafast methods provided access to the synthesis of PMA‐b‐PVA‐b‐PMA in reaction times, which depended on the temperature range, of 3–20 min. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1948–1954, 2005
Comparison of cell‐based and cell‐free protocols for producing target proteins from theArabidopsis thalianagenome for structural studies
Authors: Tyler Robert C. , Aceti David J. , Bingman Craig A. , Cornilescu Claudia C. , Fox Brian G. , Frederick Ronnie O. , Jeon Won Bae , Lee Min S. , Newman Craig S. , Peterson Francis C. , Phillips George N. , Shahan Mark N. , Singh Shanteri , Song Jikui , Sreenath Hassan K. , Tyler Ejan M. , Ulrich Eldon L. , Vinarov Dmitriy A. , Vojtik Frank C. , Volkman Brian F. , Wrobel Russell L. , Zhao Qin , Markley John L.
Published: March 2005

We describe a comparative study of protein production from 96Arabidopsis thalianaopen reading frames (ORFs) by cell‐based and cell‐free protocols. Each target was carried through four pipeline protocols used by the Center for Eukaryotic Structural Genomics (CESG), one for the production of unlabeled protein to be used in crystallization trials and three for the production of15N‐labeled proteins to be analyzed by1H‐15N NMR correlation spectroscopy. Two of the protocols involvedEscherichia colicell‐based and two involved wheat germ cell‐free technology. The progress of each target through each of the protocols was followed with all failures and successes noted. Failures were of the following types: ORF not cloned, protein not expressed, low protein yield, no cleavage of fusion protein, insoluble protein, protein not purified, NMR sample too dilute. Those targets that reached the goal of analysis by1H‐15N NMR correlation spectroscopy were scored as HSQC+ (protein folded and suitable for NMR structural analysis), HSQC± (protein partially disordered or not in a single stable conformational state), HSQC− (protein unfolded, misfolded, or aggregated and thus unsuitable for NMR structural analysis). Targets were also scored as X− for failing to crystallize and X+ for successful crystallization. The results constitute a rich database for understanding differences between targets and protocols. In general, the wheat germ cell‐free platform offers the advantage of greater genome coverage for NMR‐based structural proteomics whereas theE. coliplatform when successful yields more protein, as currently needed for crystallization trials for X‐ray structure determination. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Addressing the intrinsic disorder bottleneck in structural proteomics
Authors: Oldfield Christopher J. , Ulrich Eldon L. , Cheng Yugong , Dunker A. Keith , Markley John L.
Published: March 2005

The Center for Eukaryotic Structural Genomics (CESG), as part of the Protein Structure Initiative (PSI), has established a high‐throughput structure determination pipeline focused on eukaryotic proteins. NMR spectroscopy is an integral part of this pipeline, both as a method for structure determinations and as a means for screening proteins for stable structure. Because computational approaches have estimated that many eukaryotic proteins are highly disordered, about 1 year into the project, CESG began to use an algorithm (the Predictor of Naturally Disordered Regions, PONDR®) to avoid proteins that were likely to be disordered. We report a retrospective analysis of the effect of this filtering on the yield of viable structure determination candidates. In addition, we have used our current database of results on 70 protein targets from Arabidopsis thaliana and 1 from Caenorhabditis elegans, which were labeled uniformly with nitrogen‐15 and screened for disorder by NMR spectroscopy, to compare the original algorithm with 13 other approaches for predicting disorder from sequence. Our study indicates that the efficiency of structural proteomics of eukaryotes can be improved significantly by removing targets predicted to be disordered by an algorithm chosen to provide optimal performance. Proteins 2005. © 2005 Wiley‐Liss, Inc.
A Nine‐Coordinated ZrIV Complex and a Self‐Assembling System Obtained from a Proton Transfer Compound Containing 2,6‐Pyridinedicarboxylate and 2,6‐Pyridinediammonium; Synthesis and X‐ray Crystal Structure
Authors: Aghabozorg Hossein , Moghimi Abolghasem , Manteghi Faranak , Ranjbar Maryam
Published: March 2005

Starting with a zirconium salt and LH2, (pydaH2)2+(pydc)2−, (pyda=2, 6‐pyridinediamine; pydcH2=2,6‐pyridinedicarboxylic acid), as a 1:1 proton transfer self‐associated compound, two different compounds were resulted. One of them is a new complex of ZrIV with a flat pyridine containing ligand and structure of (pydaH)2[Zr(pydc)3] · 5H2O (1) and the other, (pydaH)+(NO3)− (2) is an ion pair with no zirconium ion. The zirconium(IV) complex (1) is crystallized in triclinic system with ${\rm P}{\bar 1}$ space group and Z = 2, the crystallographic parameters are: a = 10.612(5) Å, b = 10.617(5) Å, c = 16.815(8) Å, α = 103.654(9)°, β = 95.821(9)°, γ = 98.891(9)° and R‐value for 16767 collected reflections is 0.0592. The ion pair (2) has crystals of monoclinic system with P21 space group and Z = 2. Its crystallographic parameters are: a = 3.6227(11) Å, b = 10.034(4) Å, c = 10.296(4) Å, β = 93.422(9)° and R‐value for 4031 collected reflections is 0.0521. The two compounds were characterized with elemental analysis, ESI/MS, NMR and IR spectroscopy.
[Pb2(AMP)2(μ‐X)2X2], X = Br− and I−, AMP = 2‐aminomethylpyridine, Two New Dimeric Lead(II) Complexes Extended in One‐dimensional Helical Chain Polymers by Noncovalent π–π‐stacking
Authors: Payheghader Mahmood , Morsali Ali , Hertle Ivonne , Kempe Rhett
Published: March 2005

The two lead(II) complexes [Pb2(AMP)2(μ‐X)2X2], X = Br−, I− and AMP = 2‐aminomethylpyridine, have been synthesized and characterized. Self‐assembly of these compounds in the solid state via π–π‐stacking interactions is discussed.
Synthesis, Characterization and Crystal Structure of 4‐Amino‐1,2,4‐Δ2‐triazoline‐5‐thione and its Silver(I) Complex
Authors: Yazdanbakhsh Mohammad , Hakimi Mohammad , Heravi Majid M. , Ghassemzadeh Mitra , Neumüller Bernhard
Published: March 2005

The reaction of 4‐amino‐1,2,4‐Δ2‐triazoline‐5‐thione (ATT, 1) with AgNO3 in methanol led to the complex [Ag(ATT)2]NO3 (2). 2 was characterized by elemental analyses, 1H NMR, IR, and Raman spectroscopy as well as single‐crystal X‐ray diffraction. The molecular structure of 1 was also determined by single crystal X‐ray analysis. Crystal data for 1 at −80 C: space group C2/c with a = 2107.4(2), b = 1425.1(1), c = 688.4(1) pm, β = 104.55(1)°, Z = 16, R1 = 0.0514, crystal data for 2 at −80 °C: space group P21/c with a = 675.7(1), b = 1321.1(1), c = 1311.2(1) pm, β = 90.03(1)°, Z = 4, R1 = 0.0437.
A Series of New Molybdenum(VI) Complexes with the ONS Donor Thiosemicarbazone Ligands
Authors: Vrdoljak V. , Cindrić M. , Matković‐C̆alogović D. , Prugovec̆ki B. , Novak P. , Kamenar B.
Published: March 2005

New dioxomolybdenum(VI) complexes were obtained by the reaction of [MoO2(acac)2] with 4‐phenylthiosemicarbazone ligands derived from salicylaldehyde, 2‐hydroxy‐1‐naphthaldehyde, 2‐hydroxy‐3‐methoxybenzaldehyde or from 4‐(diethylamino)salicylaldehyde. In all complexes the ligands are coordinated to molybdenum as tridentate ONS‐donors through phenolic‐oxygen, imine‐nitrogen and thiol‐sulphur. Octahedral coordination of each Mo atom is completed either by one neutral donor molecule (D) or by the oxygen atom of the Mo=O unit from the neighbouring molecule. All compounds were characterized by means of chemical analysis, IR spectroscopy, TG and in some cases by DSC measurements, some of them by X‐ray crystallography, and by one and two‐dimensional NMR method.
3‐(Arylhydrazono)pentane‐2, 4‐diones and their Complexes with Copper(II) and Nickel(II) — Synthesis and Crystal Structures
Authors: Marten J. , Seichter W. , Weber E.
Published: March 2005

A series of new 3‐(arylhydrazono)pentane‐2, 4‐diones (1‐6) synthesized from pentane‐2, 4‐dione and diazonium salts of respective anilines using the procedure of Japp‐Klingemann are described. Complexes with CuII and NiII salts are prepared (7‐10, respectively). Spectroscopic properties of these compounds have been studied and X‐ray crystal structures of selected hydrazones (3, 4, 6) and of the hydrazone complexes (7‐10) are reported. The structures of the uncomplexed hydrazones feature an intramolecular N‐H···O interaction to yield a six‐membered H‐bond ring reflecting preference of the hydrazone tautomeric structure. All the complexes are mononuclear 2:1 (L:M) structures of six‐membered chelate type involving N2O2 binding sites that are quadratic arranged but differ in the entire coordination environment dependent on the metal and the ligand substitution including distorted octahedral and quadratic pyramidal coordination geometries in the CuII complexes 7 and 8 or nearly regular square planar coordination geometry in the NiII complexes 9 and 10, respectively. In the crystal packings, strong and weak H‐bond interactions cause supramolecular network structures.
First‐Principles Electronic Structure, Chemical Bonding, and High‐Pressure Phase Prediction of the Oxynitrides of Vanadium, Niobium, and Tantalum
Authors: Lumey Marck‐Willem , Dronskowski Richard
Published: March 2005

The oxynitrides of vanadium, niobium and tantalum were investigated by density‐functional theory (LDA & GGA; plane waves & muffin – tin orbitals; pseudopotentials & all‐electron approaches). We propose a high‐pressure synthesis of stoichiometric VON beyond 12 GPa, and the unknown phase is predicted to be a small band‐gap semiconductor. Its structure is of the baddeleyite type which is also adapted by the higher homologues, TaON and NbON, at ambient pressure. Further, the high‐pressure phases of NbON and TaON were studied and phase transitions into the cotunnite type are predicted to occur at approximately 27 and 31 GPa, respectively. Electronic‐structure calculations on these high‐pressure phases show that TaON is a small band‐gap semiconductor whereas NbON appears to be a metallic conductor.
(Mis)alignments in Counseling for Huntington's Disease Predictive Testing: Clients’ Responses to Reflective Frames
Authors: Sarangi Srikant , Bennert Kristina , Howell Lucy , Clarke Angus , Harper Peter , Gray Jonathon
Published: March 2005

As a sequel to an earlier paper (Sarangi et al., 2004. J Genet Couns, 13(2), 135–155) examining genetic counselors’ initiation of reflective frames, in this paper we analyze the variable ways in which clients respond to such reflective frames in the clinical setting. Of the six types of reflective questions identified, we focus on two types, which recur throughout the counseling protocol: (i) questions about clients’ decisions to have genetic testing and (ii) questions exploring the potential impact of a positive or negative test result. The analytic focus here is on the mismatches surrounding clients’ apparent readiness to discuss coping with the onset of disease (risk of disease) when they have been asked to discuss coping with genetic test results (risk of knowing). Our theoretical discussion is centered around the notion of alignment as a framework for locating the convergence and divergence of counselors’ and clients’ agendas in interaction. Drawing on detailed transcripts of 24 Huntington's Disease counseling consultations in South Wales, we analyze 119 counselor–client question–response sequences using the methodology of discourse analysis. Preliminary coding of clients’ responses led us to identify three recurrent themes: (a) gaining knowledge as a basis for future action; (b) needing to know as a subjective necessity; and (c) downplaying what can be known. In a further analysis of extended data extracts, we draw attention to how clients display varying degrees of engagement with regard to the testing process and outcomes along the temporal and social axes. At one extreme, clients may take up the opportunity to engage in self‐reflection, and thus endorse the legitimacy of the reflective frame. At the other extreme, clients may implicitly or explicitly challenge the relevance of self‐reflection, and hence the usefulness of this counselor‐initiated routine. We suggest that clients’ varied response behaviors result from the perceived need of some clients to display their ‘readiness’ for predictive testing—an overarching ‘meta‐question’ posed by the very existence of the counseling protocol.
Echocardiographic ejection fraction in patients with acute heart failure: correlations with hemodynamic, clinical, and neurohormonal measures and short‐term outcome
Authors: Uriel Nir , Torre‐Amione Guillermo , Milo Olga , Kaluski Edo , Perchenet Loïc , Blatt Alex , Kobrin Isaac , Turnovski Arkadi , Kaplan Shoshana , Rainisio Maurizio , Frey Aline , Vered Zvi , Cotter Gad
Published: March 2005

Background

Although echocardiographic ejection fraction (EF) is frequently used for the estimation of left ventricular contractility in patients with acute heart failure, its exact role and correlations with clinical, hemodynamic, and neurohormonal variables of cardiac contractility is not known.

Methods

Patients (343) with acute heart failure, enrolled into two prospective placebo‐controlled hemodynamic studies of tezosentan, and in whom EF was available at baseline, were included. Outcome was evaluated in a subset of 94 patients who were enrolled in the placebo arms of the studies.

Results

Higher echocardiographic EF was correlated with older age, increased incidence of hypertension and atrial fibrillation, and female gender. We observed weak correlation between EF and cardiac output or cardiac power and no correlation with wedge pressure, and the change in hemodynamic variables over time. Higher EF was correlated with more baseline leukocytosis and higher plasma levels of endothelin‐1 and blood urea nitrogen, while lower EF was related to higher baseline B‐type natriuretic peptide (BNP). We observed no overall correlations between EF and outcome.

Conclusions

In patients with acute heart failure, echocardiographic EF is weakly correlated with hemodynamic measures of left ventricular contractility and outcome; hence, it should be interpreted cautiously when evaluating patients admitted due to acute heart failure.
‘The eternal enemy of Isla¯m’: Abdullah Cevdet and the Baha'i religion
Authors: ALKAN NECATI
Published: March 2005

This paper discusses Abdullah Cevdet, one of the founding members of the Young Turk ‘Committee of Union and Progress’, who in 1922 caused considerable public commotion by publishing an article favourable to the Baha'i religion in his journal İctihâd. He was prosecuted for attacking Islam and the prophet Mohammad by expressing his thoughts in favour of the Baha'i religion, recommending it as a world religion to replace Islam, which he deemed to be backward. It is argued here, in the context of Cevdet's Weltanschauung, that he did not use ‘Baha'ism’ merely as a tool to educate the Muslims in line with his Positivist ideas but that he identified himself with this new religious creed.
Culture, society and evolutionary theory
Authors: Shennan Stephen
Published: March 2005

Kristiansen's paper represents a typically stimulating and thoughtful response to some of the recent theoretical trends in archaeology, and it is equally characteristic of his now long-established ‘public intellectual’ role in European archaeology that he should want to bring his concerns into the arena of open debate and to explore common ground between different perspectives. I find myself in agreement with many of his conclusions, of course without accepting his view that they are largely incompatible with the Darwinian view that he criticizes. In what follows I want to respond to some of his criticisms and address what I see as some of his misconceptions about the nature of evolutionary approaches and their implications for understanding the human past.
A comparison of methane flux in a boreal landscape between a dry and a wet year
Authors: Bubier Jill , Moore Tim , Savage Kathleen , Crill Patrick
Published: March 2005

We used field measurements of methane (CH4) flux from upland and wetland soils in the Northern Study Area (NSA) of BOREAS (BOReal Ecosystem‐Atmosphere Study), near Thompson, Manitoba, during the summers of 1994 and 1996 to estimate the overall CH4 emission from a 1350 km2 landscape. June–September 1994 and 1996 were both drier and warmer than normal, but summer 1996 received 68 mm more precipitation than 1994, a 40% increase, and had a mean daily air temperature 0.6°C warmer than 1994. Upland soils consumed CH4 at rates from 0 to 1.0 mg m−2 d−1, with small spatial and temporal variations between years, and a weak dependence on soil temperature. In contrast, wetlands emitted CH4 at seasonal average rates ranging from 10 to 350 mg CH4 m−2 d−1, with high spatial and temporal variability, and increased an average of 60% during the wetter and warmer 1996. We used Landsat imagery, supervised classification, and ground truthing to scale point CH4 fluxes (<1 m2) to the landscape (>1000 km2). We performed a sensitivity analysis for error terms in both areal coverage and CH4 flux, showing that the small areas of high CH4 emission (e.g., small ponds, graminoid fens, and permafrost collapse margins) contribute the largest uncertainty in both flux measurements and mapping. Although wetlands cover less than 30% of the landscape, areally extrapolated CH4 flux for the NSA increased by 61% from 10 to16 mg CH4 m−2 d−1 between years, entirely attributed to the increase in wetland CH4 emission. We conclude that CH4 fluxes will tend to be underestimated in areas where much of the landscape is covered by wetlands. This is due to the large spatial and temporal variability encountered in chamber‐based measurements of wetland CH4 fluxes, strong sensitivity of wetland CH4 emission to small changes in climate, and because most remote sensing images do not adequately identify small areas of high CH4 flux.
Volcanism in compressional tectonic settings: Is it possible?
Authors: Tibaldi Alessandro
Published: March 2005

This study presents the first field evidence of emplacement of a huge stratovolcano within contractional tectonics, in spite of the widely accepted idea that volcanism can develop only in extensional or transcurrent tectonic settings. El Reventador volcano (Ecuador) started to grow 0.32 Ma BP and is still active. During pre‐El Reventador times, its substratum has been affected by N‐S‐ to NNE‐striking reverse faults. During late Pleistocene‐Holocene, some reverse faults with the same orientations were still active, locally with a component of right‐lateral strike‐slip motions. Seismicity shows widespread events with intensity up to 6.9 Mw and compression. Some of these faults cut the volcano creating differential uplift along N‐S‐ to NNE‐trending tectonic blocks. Hypocenter swarms and field data indicate east‐vergent basal thrusting under the volcano and N‐S‐trending fault‐propagation folds to the east. A model for magma migration in this setting is proposed, suggesting that similar cases of volcanism within a dominantly contractional tectonic regime may be more frequent than previously thought.
The Shiga toxin-producing Escherichia coli, their ruminant hosts, and potential on-farm interventions: a review
Authors: Vanselow B. A. , Krause D. O. , McSweeney C. S.
Published: March 2005

The emergence of Shiga toxin-producing Escherichia coli serotype O157:H7 as a major human pathogen over the last 2 decades has focused attention on this organism’s ruminant hosts. Despite implementation of conventional control methods, people continue to become seriously ill from contaminated meat or other food products, manure-contaminated drinking and recreational water, and direct contact with ruminants. E. coli O157:H7 can cause life-threatening disease, and is a particular threat to children, through acute and chronic kidney damage. Compared with other food-borne bacteria, E. coli O157:H7 has a remarkably low infectious dose and is environmentally robust. Cattle are largely unaffected by this organism and have been identified as the major source of E. coli O157:H7 entering the human food chain. Other Shiga toxin-producing E. coli can be pathogenic to humans and there is increasing evidence that their significance has been underestimated. Governments around the world have acted to tighten food safety regulations, and to investigate animal sources and on-farm control of this and related organisms. Potential intervention strategies on-farm include: feed and water hygiene, altered feeding regimes, specific E. coli vaccines, antibacterials, antibiotics, probiotics, and biological agents or products such as bacteriophages, bacteriocins, or colicins.
Incidence and distribution of Barley yellow dwarf virus and Cereal yellow dwarf virus in over-summering grasses in a Mediterranean-type environment
Authors: Hawkes J. R. , Jones R. A. C.
Published: March 2005

During the summer periods of 2000 and 2001, incidences of infection with Barley yellow dwarf virus (BYDV) and Cereal yellow dwarf virus (CYDV) were determined in grass weeds and volunteer cereals surviving at isolated sites throughout the grainbelt of south-western Australia, which has a Mediterranean-type climate. Samples of Cynodon dactylon, Eragrostis curvula, Erharta calycina, Pennisetum clandestinum, and volunteer cereals (mostly wheat) were tested for BYDV (serotypes MAV, PAV and RMV) and CYDV (serotype RPV), and those of at least 19 other grass species were tested for BYDV only (serotypes PAV and MAV). In 2000, BYDV and/or CYDV were detected in 33% of 192 sites in 0.7% of 26 700 samples, and in 2001 the corresponding values were 19% of 176 sites and 0.5% of 21 953 samples. Infection was distributed relatively evenly throughout the different annual average rainfall zones of the grainbelt, but when sites were categorised according to actual rainfall for late spring to early autumn, the proportion of sites and samples infected increased where such rainfall exceeded 300 mm. In both summer sampling periods, the most abundant grass species were C. dactylon and E. curvula, with BYDV and/or CYDV being detected in 0.1–0.6% and 0.1–0.5% of samples, respectively. The corresponding incidences were 0–1% for Erharta calycina, 7–8% for P. clandestinum, and 0.2–2% for volunteer wheat. The most abundant species tested for BYDV only were Chloris truncata and Digitaria sanguinalis, with infection incidences of 0.2–0.7 and 0.2–0.3%, respectively. Chloris virgata (2–3%) and Urochloa panicoides (0.3–0.6%) were the only other infected species. Within individual sites and host species, the greatest incidences of CYDV were in P. clandestinum (23% in 2000 and 18% in 2001) and of BYDV in Chloris virgata (14% with PAV and 12% with MAV in 2000). Small populations of grass-infesting aphids were found over-summering at 26% (2000) and 3% (2001) of sites and occurred in all 3 annual rainfall zones. The predominant species was Hysteroneura setariae, but Rhopalosiphum maidis, R. padi, and Sitobion miscanthi occurred occasionally. Presence of over-summering BYDV, CYDV, and aphids in all rainfall zones has important implications for virus spread to cereal crops throughout the grainbelt.
Predicting the Bioavailability of Metals and Metal Complexes: Critical Review of the Biotic Ligand Model
Authors: Slaveykova Vera I. , Wilkinson Kevin J.
Published: March 2005

Environmental Context. The chemical speciation of trace metals greatly influences their biological effects. Nonetheless, no clear consensus currently exists as to when metal complexes are bioavailable, especially for field conditions. Recently, the USA EPA has incorporated the biotic ligand model (BLM) into their regulatory framework and many other countries are now examining the implications of following suit. This review examines the fundamental basis of the BLM in order to provide the reader with an understanding of its potential uses and limitations. Abstract. The biotic ligand model is a useful construct both for predicting the effects of metals to aquatic biota and for increasing our mechanistic understanding of their interactions with biological surfaces. Since biological effects due to metals are always initiated by metal bioaccumulation, the fundamental processes underlying bio-uptake are examined in this review. The model assumes that the metal of interest, its complexes, and metal bound to sensitive sites on the biological surface are in chemical equilibrium. Therefore, many of the equilibrium constants required for the model have been compiled and their methods of determination evaluated. The underlying equilibrium assumption of the BLM is also examined critically. In an attempt to identify which conditions are appropriate for its application, several documented examples of failures of the BLM are discussed. Finally, the review is concluded by identifying some important future research directions.
The Chemical Weather
Authors: Lawrence Mark G. , Hov Øystein , Beekmann Matthias , Brandt Jørgen , Elbern Hendrik , Eskes Henk , Feichter Hans , Takigawa Masayuki
Published: March 2005

Environmental Context. Meteorological weather—temperature, pressure, wind direction—is familiar to all, and contrasts with meteorological climate in short-term (weather) versus long-term (climate) influence. From the atmospheric chemistry side, the focus has largely been on the chemical climate, the long-term mean concentrations of important trace gases and aerosols. An emerging new focus of study is the chemical weather—the tremendous short-term variability of the atmospheric chemical composition, resulting from the strong influence of meteorological variability, chemical complexity, and regionally and temporally varying emissions.
His6tag-assisted chemical protein synthesis
Authors: Bang Duhee , Kent Stephen B. H.
Published: March 2005

To make more practical the total chemical synthesis of proteins by the ligation of unprotected peptide building blocks, we have developed a method to facilitate the isolation and handling of intermediate products. The synthetic technique makes use of a His6tag at the C terminus of the target polypeptide chain, introduced during the synthesis of the C-terminal peptide segment building block. The presence of a His6tag enables the isolation of peptide or protein products directly from ligation reaction mixtures by Ni-NTA affinity column purification. This simple approach enables facile buffer exchange to alternate reaction conditions and is compatible with direct analytical control by protein MS of the multiple ligation steps involved in protein synthesis. We used syntheses of crambin and a modular tetratricopeptide repeat protein of 17 kDa as models to examine the utility of this affinity purification approach. The results show that His6tag-assisted chemical protein synthesis is a useful method that substantially reduces handling losses and provides for rapid chemical protein syntheses.
Big brains, enhanced cognition, and response of birds to novel environments
Authors: Sol Daniel , Duncan Richard P. , Blackburn Tim M. , Cassey Phillip , Lefebvre Louis
Published: March 2005

The widely held hypothesis that enlarged brains have evolved as an adaptation to cope with novel or altered environmental conditions lacks firm empirical support. Here, we test this hypothesis for a major animal group (birds) by examining whether large-brained species show higher survival than small-brained species when introduced to nonnative locations. Using a global database documenting the outcome of >600 introduction events, we confirm that avian species with larger brains, relative to their body mass, tend to be more successful at establishing themselves in novel environments. Moreover, we provide evidence that larger brains help birds respond to novel conditions by enhancing their innovation propensity rather than indirectly through noncognitive mechanisms. These findings provide strong evidence for the hypothesis that enlarged brains function, and hence may have evolved, to deal with changes in the environment.
Ancient DNA from giant extinct lemurs confirms single origin of Malagasy primates
Authors: Karanth K. Praveen , Delefosse Thomas , Rakotosamimanana Berthe , Parsons Thomas J. , Yoder Anne D.
Published: March 2005

The living Malagasy lemurs constitute a spectacular radiation of >50 species that are believed to have evolved from a common ancestor that colonized Madagascar in the early Tertiary period. Yet, at least 15 additional Malagasy primate species, some of which were relative giants, succumbed to extinction within the past 2,000 years. Their existence in Madagascar is recorded predominantly in its Holocene subfossil record. To rigorously test the hypothesis that all endemic Malagasy primates constitute a monophyletic group and to determine the evolutionary relationships among living and extinct taxa, we have conducted an ancient DNA analysis of subfossil species. A total of nine subfossil individuals from the extinct genera
Palaeopropithecus
and
Megaladapis
yielded amplifiable DNA. Phylogenetic analysis of cytochrome
b
sequences derived from these subfossils corroborates the monophyly of endemic Malagasy primates. Our results support the close relationship of sloth lemurs to living indriids, as has been hypothesized on morphological grounds. In contrast,
Megaladapis
does not show a sister-group relationship with the living genus
Lepilemur
. Thus, the classification of the latter in the family Megaladapidae is misleading. By correlating the geographic location of subfossil specimens with relative amplification success, we reconfirm the global trend of increased success rates of ancient DNA recovery from nontropical localities.
In vivo
dynamics of retinal injury and repair in the
rhodopsin
mutant dog model of human retinitis pigmentosa
Authors: Cideciyan Artur V. , Jacobson Samuel G. , Aleman Tomas S. , Gu Danian , Pearce-Kelling Susan E. , Sumaroka Alexander , Acland Gregory M. , Aguirre Gustavo D.
Published: March 2005

Genetic and environmental factors modify the severity of human neurodegenerations. Retinal degenerations caused by
rhodopsin
gene mutations show severity differences within and between families and even within regions of the same eye. Environmental light is thought to contribute to this variation. In the naturally occurring dog model of the human disorder, we found that modest light levels, as used in routine clinical practice, dramatically accelerated the neurodegeneration. Dynamics of acute retinal injury (consisting of abnormal intraretinal light scattering) were visualized
in vivo
in real time with high-resolution optical imaging. Long term consequences included fast or slow retinal degeneration or repair of injury depending on the dose of light exposure. These experiments provide a platform to study mechanisms of neuronal injury, repair, compensation, and degeneration. The data also argue for a gene-specific clinical trial of light reduction in human
rhodopsin
disease.
Defective N-acetylaspartate catabolism reduces brain acetate levels and myelin lipid synthesis in Canavan's disease
Authors: Madhavarao Chikkathur N. , Arun Peethambaran , Moffett John R. , Szucs Sylvia , Surendran Sankar , Matalon Reuben , Garbern James , Hristova Diana , Johnson Anne , Jiang Wei , Namboodiri M. A. Aryan
Published: March 2005

Canavan's disease (CD) is a fatal, hereditary disorder of CNS development that has been linked to mutations in the gene for the enzyme aspartoacylase (ASPA) (EC 3.5.1.15). ASPA acts to hydrolyzeN-acetylaspartate (NAA) intol-aspartate and acetate, but the connection between ASPA deficiency and the failure of proper CNS development is unclear. We hypothesize that one function of ASPA is to provide acetate for the increased lipid synthesis that occurs during postnatal CNS myelination. The gene encoding ASPA has been inactivated in the mouse model of CD, and here we show significant decreases in the synthesis of six classes of myelinassociated lipids, as well as reduced acetate levels, in the brains of these mice at the time of peak postnatal CNS myelination. Analysis of the lipid content of white matter from a human CD patient showed decreased cerebroside and sulfatide relative to normal white matter. These results demonstrate that myelin lipid synthesis is significantly compromised in CD and provide direct evidence that defective myelin synthesis, resulting from a deficiency of NAA-derived acetate, is involved in the pathogenesis of CD.