bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characteristics of halloysite associated with rectorite from Hubei, China
Authors: Hong H.-L. , Mi J.-X. 
Published: August 2006

AbstractThe mineralogical characteristics of halloysite in rectorite pelite in the Zhongxiang area, Hubei, China, were investigated using X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy methods. The results show that halloysite crystals exhibit euhedral lamellar, tubular or club-like, and needle-like or fibre-like morphologies, indicating that they crystallized from a significantly water-saturated environment. The mineral assemblage of the rectorite pelite is rectorite, halloysite, illite, gypsum, pyrite and rutile, suggesting a weak supergene alteration. Several features related to crystallization of halloysite were noted. Growth of halloysite on rectorite edge surfaces in voids and twins of halloysite on a nanometer scale with composition plane (110) were found in the Zhongxiang rectorite pelite, and, in particular, the tapered ends of tubes suggest that halloysite crystallized from solution. Disaggregation of lamellar halloysite particles into parallel clusters of single tubular halloysite crystals suggests that because of significant [H2O] activity in the environment, halloysite may have been derived from the alteration of rectorite.
The missing sulphur in mattheddleite, sulphur analysis of sulphates, and paragenetic relations at Leadhills, Scotland
Authors: Essene E. J. , Henderson C. E. , Livingstone A. 
Published: August 2006

AbstractPublished electron microprobe analyses of mattheddleite, a lead sulpho-silicate apatite from Leadhills, Scotland, have 9–13% IV site deficiencies. However, galena was used as a standard for S, which suggested that low S resulted from a shift in the S-Kα peak. Wavelength scans with a PET crystal show that the S-Kα peak is shifted down by 0.0026 Å for sulphates relative to sulphides. Quantitative analyses show a ∼30% increase of S in mattheddleite using a celestite standard, which fills the IV site, but with Si > S, on average Pb5S1.2Si1.8O11.7Cl0.6(OH)0.4. Direct analysis of oxygen with the electron microprobe implies that the charge imbalance engendered from the inequality of Si and S is compensated with substitution of a vacancy (□), as in Pb5S1.2Si1.8[O11.7□0.3] [Cl0.6(OH)0.4] or Pb5S1.2Si1.8[O11.7(Cl, OH)0.73]. [Cl,OH)0.7 □0.3]. Calculation of OH as l–C1 suggests the presence of both OH- and Cl-dominant mattheddleite at Leadhills, but direct analysis of H is needed to confirm the dominance of OH in the channel site. Wavelength-dispersive analyses of S in apatite and other sulphates must be undertaken with sulphate standards: use of sulphide standards yields a negative error on the order of 10–20% in the resultant S concentration. Reactions of mattheddleite with other Pb minerals at Leadhills show that their stability depends on fluid composition as well as pressure and temperature. An X-ray map of Cl shows complex zoning between Cl-poor and Cl-rich mattheddleite, recording rapid changes in the fluid chemistry during late-stage hydrothermal processes at Leadhills.
The origin of the hydrous scandium phosphate, kolbeckite, from the Hagendorf-Pleystein pegmatite province, Germany
Authors: Dill H.G. , Weber B. , Füssl M. , Melcher F. 
Published: August 2006

AbstractThe rare hydrous scandium phosphate, kolbeckite, [Sc(PO4).2H2O], has been recognized for the first time from the Hagendorf-Pleystein pegmatite province. The mineral was formed by the alteration of quartz-rich relict cores of pegmatites containing rutile, ilmenite, columbite, pyrochlore, wolframite, monazite and apatite. The alteration process involved acidic meteoric water and was not related to low-temperature hydrothermal fluids. Scandium and phosphorous for the formation of the kolbeckite were provided by the decomposition of the primary oxides and phosphates, respectively. Hydrous Sc phosphates are considered to form only during advanced stages of weathering in Al- and Fe-poor environments. In Al- and Fe-rich environments Sc is scavenged from solution as a trace component of Al- and Fe phosphates. A special type of leucoxene containing Fe, Al and P was formed during the process of formation of kolbeckite. In the absence of phosphate anions, Sc is removed in solution and ‘normal’ leucoxene is formed.
Characterization of fluoro-edenite by μ-Raman and μ-FTIR spectroscopy
Authors: Rinaudo C. , Cairo S. , Gastaldi D. , Gianfagna A. , Mazziotti Tagliani S. , Tosi G. , Conti C. 
Published: August 2006

AbstractThe prismatic variety of fluoro-edenite, a new amphibole found in lavas from Mt Etna in Biancavilla (Catania Province, Sicily, Italy), has been characterized by μ-Raman and μ-FTIR spectroscopy. The wavenumbers at which the bands are detected in the μ-Raman and μ-FTIR spectra are compared with tremolite, asbestos the chemical and crystallographic characteristics of which are very similar to those of fluoro-edenite.
An XRD, SEM and TG study of a uranopilite from Australia
Authors: Frost R.L. , Weier M.L. , Ayoko G.A. , Martens W. , Čejka J. 
Published: August 2006

AbstractA uranopilite from The South Alligator River, Northern Territory, Australia, has been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) with EDAX attachment, and thermogravimetry in conjunction with evolved gas mass spectrometry. The XRD shows that the mineral is a pure uranopilite with few if any impurities. The SEM images show that the uranopilite consists of elongated crystals, up to 50μm long and 5 μm wide. Thermogravimetry combined with mass spectrometry shows that dehydration occurs at ∼31°C resulting in the formation of metauranopilite. The first dehydration step over 20–71°C corresponds to a decrease of 5.4 wt.%, equivalent to 6.076 H2O. The second dehydration step, over the temperature range 71 –162.4°C corresponds to a decrease of 4.7 wt.%, equivalent to 5.288 H2O, making a total of 11.364 moles of H2O, close to 12 H2O for uranopilite.Dehydroxylation takes place over the temperature range 80–160°C. The loss of sulphate occurs at higher temperatures in two steps at 622 and 636°C. A mass loss also occurs at 755°C, accounted for by evolved oxygen.
Structural changes induced by cation ordering in ferrotapiolite
Authors: Zema M. , Tarantino S.C. , Giorgiani A. 
Published: August 2006

AbstractStructural modifications as a function of the degree of order (Q) in FeTa2O6ferrotapiolite have been characterized by means of single-crystal X-ray diffraction (SC-XRD). A total of 26 datasets covering the range ofQbetween 0.154 and 1 have been obtained by thermal treatments followed by quenching of natural tapiolite crystals. Ordering of Fe2+at theAsites and of Ta5+at theBsites causes a linear increase in thea/clattice constants ratio, as a consequence of a linear decrease of the c dimension and only slight modifications of theaparameter. Calibration ofa/c vs. Qrepresents a very useful tool for a rapid determination of the degree of order of tapiolite samples. Polyhedral volumes of the two octahedral sites vary linearly withQas a consequence of the different ionic radii of the two species. Both the sites remain almost regular at allQvalues but theBsite shows an increasing off-centre displacement of the cation with increasingQ.Observed structure factors of supercell reflections, characterized byl≠ 3n, increase linearly as a function ofQ,thus representing a further tool for a quick evaluation of the degree of order.
Differential kinase requirements in human and mouse Fc-gamma receptor phagocytosis and endocytosis
Authors: Huang Zhen-Yu , Barreda Daniel R , Worth Randall G , Indik Zena K , Kim Moo-Kyung , Chien Paul , Schreiber Alan D 
Published: August 2006

Abstract
Fc gamma receptors (FcγRs) contribute to the internalization of large and small immune complexes through phagocytosis and endocytosis, respectively. The molecular processes underlying these internalization mechanisms differ dramatically and have distinct outcomes in immune clearance and modulation of cell function. However, it is unclear how the same receptors (FcγR) binding to identical ligands (IgG) can elicit such distinct responses. We and others have shown that Syk kinase, Src-related tyrosine kinases (SRTKs) and phosphatidyl inositol 3-kinases (PI3K) play important roles in FcγR phagocytosis. Herein, we demonstrate that these kinases are not required for FcγR endocytosis. Endocytosis of heat-aggregated IgG (HA-IgG) by COS-1 cells stably transfected with FcγRIIA or chimeric FcγRI-γ-γ (EC-TM-CYT) was not significantly altered by PP2, piceatannol, or wortmannin. In contrast, phagocytosis of large opsonized particles (IgG-sensitized sheep erythrocytes, EA) was markedly reduced by these inhibitors. These results were confirmed in primary mouse bone marrow-derived macrophages and freshly isolated human monocytes. Levels of receptor phosphorylation were similar when FcγRIIA was cross-linked using HA-IgG or EA. However, inhibition of FcγR phosphorylation prevented only FcγR phagocytosis. Finally, biochemical analyses of PI3K(p85)-Syk binding indicated that direct interactions between native Syk and PI3K proteins are differentially regulated during FcγR phagocytosis and endocytosis. Overall, our results indicate that FcγR endocytosis and phagocytosis differ dramatically in their requirement for Syk, SRTKs, and PI3K, pointing to striking differences in their signal transduction mechanisms. We propose a competitive inhibition-based model in which PI3K and c-Cbl play contrasting roles in the induction of phagocytosis or endocytosis signaling cascades.
CD69 targeting differentially affects the course of collagen-induced arthritis
Authors: Sancho David , Gómez Manuel , Martinez del Hoyo Gloria , Lamana Amalia , Esplugues Enric , Lauzurica Pilar , Martinez-A Carlos , Sánchez-Madrid Francisco 
Published: August 2006

Abstract
CD69 expression is induced following activation of leukocytes at inflammatory sites and plays a negative regulatory role in the development of collagen-induced arthritis (CIA). To evaluate potential strategies of CD69 targeting in chronic inflammatory diseases, two different anti-CD69 mAbs were generated and their effects on CIA were studied. Administration of the IgG1 anti-CD69 mAb 2.2 to DBA/1 mice with CIA led to an exacerbation of the disease, correlated with down-modulation of CD69 from the cell surface, and reproduced the phenotype of the CD69(−/−) mouse in wild-type animals. In contrast, treatment with the IgG2a anti-CD69 mAb 2.3 was effective in ameliorating CIA when administered in the early or intermediate phases of the disease, causing a decreased production of proinflammatory cytokines in inflammatory foci. Monoclonal antibody 2.3 induces partial depletion of CD69+ cells in vivo. Moreover, adoptive transfer of type-II collagen (CII)-sensitized cells treated with mAb 2.3 to deplete CD69+ cells did not result in arthritis. The attenuation of inflammation correlates with reduced lymphocyte proliferative response in response to CII and with a reduction in the frequency of CII-specific T cells producing IFN-γ. We thus conclude that CD69 targeting by mAbs can either enhance or dampen the immune response.
Liposome-mediated RNA transfection should be used with caution
Authors: Barreau Carine , Dutertre Stéphanie , Paillard Luc , Osborne H. Beverley 
Published: August 2006

Liposome-mediated RNA transfection appears to present a number of advantages for studying the metabolism of reporter mRNAs in mammalian cells. This method is also widely used to transfect siRNAs. Here we describe results indicating that reporter mRNAs introduced into HeLa cells by liposomes do not present the expected behaviors. Namely, the stability of reporter mRNAs was independent of the presence or absence of an AUUUA instability element, a poly(A) tail, or even a 5′ methylated cap. Confocal microscopy showed that fluorescent RNAs introduced by liposome-mediated transfection were present in discrete particles. These observations imply that a number of control experiments are required when using liposome to mediated RNA transfection, and the possible consequences are discussed.
Fatal postlymphoma chemotherapy hepatitis B reactivation secondary to the emergence of a YMDD mutant strain with lamivudine resistance in a noncirrhotic patient
Authors: Law Joanna K. , Ali Jaber Al , Harrigan P. Richard , Sherlock Christopher H. , Savage Kerry J. , Yoshida Eric M. 
Published: August 2006

AbstractHepatitis B reactivation is a well‐known complication during or after chemotherapy in chronic hepatitis B (HBV) carriers. The current practice guidelines in Canada and the United States recommends patients receive antiviral prophylaxis prior to the onset of chemotherapy in chronic HBV carriers with lamivudine. We report a case of a 57‐year‐old man with follicular lymphoma on lamivudine prophylaxis and no clinical evidence of cirrhosis, and developed fatal HBV reactivation after the emergence of a YMDD mutant strain of HBV that confers lamivudine resistance. Fatal reactivation secondary to the development of lamivudine resistance has not, to date, been well‐ reported. Our experience indicates the need to carefully monitor patients for suspected drug‐ resistant HBV mutants with the addition of anti‐viral agents effective against the YMDD mutational strain, when lamivudine resistance emerges. Am. J. Hematol., 2006. © 2006 Wiley‐Liss, Inc.
Humanization of anti‐human insulin receptor antibody for drug targeting across the human blood–brain barrier
Authors: Boado Ruben J. , Zhang Yufeng , Zhang Yun , Pardridge William M. 
Published: August 2006

AbstractA murine monoclonal antibody (MAb) to the human insulin receptor (HIR) has been engineered for use as a brain drug delivery system for transport across the human blood–brain barrier (BBB). The HIRMAb was humanized by complementarity determining region (CDR) grafting on the framework regions (FR) of the human B43 IgG heavy chain and the human REI kappa light chain. A problem encountered in the humanization process was the poor secretion of the CDR‐grafted HIRMAb by myeloma cells. This problem was solved by the production of human/mouse hybrids of the engineered heavy chain variable region (VH), which led to the replacement of five amino acids in the FR3 of the VH with original murine amino acids. No replacement of FR amino acids in the light chain variable region (VL) was required. The affinity of the humanized HIRMAb for the HIR was decreased 27% relative to the murine HIRMAb. The humanized HIRMAb avidly bound to the HIR of isolated human brain capillaries, which are used as an in vitro model system of the human BBB. The HIRMAb cross reacts with the HIR of Old World primates such as the Rhesus monkey. The humanized HIRMAb was radiolabeled with 125‐iodine, and injected intravenously into an adult, anesthetized Rhesus monkey. Brain scanning showed the humanized HIRMAb was rapidly transported into all parts of the primate brain after intravenous administration. The humanized HIRMAb may be used as a brain drug and gene delivery system for the targeting of large molecule therapeutics across the BBB in humans. Biotechnol. Bioeng. 2007;96: 381–391. © 2006 Wiley Periodicals, Inc.
Comparison of two continuous fungal bioreactors for posttreatment of anaerobically pretreated weak black liquor from kraft pulp mills
Authors: Ortega‐Clemente Alfredo , Marín‐Mezo G. , Ponce‐Noyola M.T. , Montes‐Horcasitas M.C. , Caffarel‐Méndez S. , Barrera‐Cortés Josefina , Poggi‐Varaldo Héctor M. 
Published: August 2006

AbstractThe purpose of this work was to evaluate and compare two continuous systems of posttreatment of anaerobically pretreated weak black liquor (WBL). The first system consisted of a packed bed reactor (PBR) with Trametes versicolor (Tv) immobilized on wood cubes of holm oak (biocubes). The second system was a fluidized bed reactor (FBR) with Lentinus edodes (Le) immobilized on wood cubes of holm oak. The reactors operated for 65 days at a hydraulic retention time (HRT) of 5 days, at 28°C, with continuous aeration. Response variables monitored were conventional and specific, unit, net removal efficiency (η and ηsun, respectively) of chemical oxygen demand (COD), color, and ligninoids, and enzymatic activities of manganese peroxidase (MnP), lignin peroxidase (LiP), laccase (Lac) and proteases. The PBR showed an average color η superior to that of the FBR (52.42 ± 21.78% and 25.34 ± 14.38% for PBR and FBR, respectively); removals of COD and ligninoids presented a similar pattern to that of color. Lac activity was significantly larger in PBR than in FBR. Activity of MnP in PBR was higher than that of the FBR (0.004 and 0.002 U MnP/mL, respectively). This difference could be ascribed to the different fungi present in each bioreactor. LiP activity was very low in both reactors. Average value of proteases was almost double in the FBR as compared with PBR (0.472 and 0.209 U Proteases/mL, respectively). During the last 2 weeks of operation, biocubes in the FBR experienced a significant loss of the attached Le biomass, probably by attrition. This and higher protease activity in the FBR could explain the lower pollutant removals achieved in the FBR. Overall, PBR with immobilized Tv showed a better performance than the FBR with Le for the posttreatment of the recalcitrant anaerobic effluent. Extended and sustained pollutant removal (65 days) was achieved in the PBR, although more research is needed to evaluate bioreactor performance at shorter hydraulic retention times. Biotechnol. Bioeng. 2007;96:640–650. © 2006 Wiley Periodicals, Inc.
Amino acid and manganese supplementation modulates the glycosylation state of erythropoietin in a CHO culture system
Authors: Crowell Christopher K. , Grampp Gustavo E. , Rogers Gary N. , Miller Janis , Scheinman Robert I. 
Published: August 2006

AbstractThe manufacture of secreted proteins is complicated by the need for both high levels of expression and appropriate processing of the nascent polypeptide. For glycoproteins, such as erythropoietin (EPO), posttranslational processing involves the addition of oligosaccharide chains. We initially noted that a subset of the amino acids present in the cell culture media had become depleted by cellular metabolism during the last harvest cycle in our batch fed system and hypothesized that by supplementing these nutrients we would improve EPO yields. By increasing the concentration of these amino acids we increased recombinant human erythropoietin (rHuEPO) biosynthesis in the last harvest cycle as expected but, surprisingly, we also observed a large increase in the amount of rHuEPO with a relatively low sialic acid content. To understand the nature of this process we isolated and characterized the lower sialylated rHuEPO pool. Decreased sialylation correlated with an increase in N‐linked carbohydrates missing terminal galactose moieties, suggesting that β‐1,4‐galactosyltransferase may be rate limiting in our system. To test this hypothesis we supplemented our cultures with varying concentrations of manganese (Mn2+), a cofactor for β‐1,4‐galactosyltransferase. Consistent with our hypothesis we found that Mn2+ addition improved galactosylation and greatly reduced the amount of rHuEPO in the lower sialylated fraction. Additionally, we found that Mn2+ addition increased carbohydrate site occupancy and narrowed carbohydrate branching to bi‐antennary structures in these lower sialylated pools. Surprisingly Mn2+ only had this effect late in the culture process. These data indicate that the addition of Mn2+ has complex effects on stressed batch fed cultures. Biotechnol. Bioeng. 2007;96: 538–549. © 2006 Wiley Periodicals, Inc.
Proton Transfer 200 Years after von Grotthuss: Insights from Ab Initio Simulations
Authors: Marx Dominik 
Published: August 2006

AbstractIn the last decade, ab initio simulations and especially Car–Parrinello molecular dynamics have significantly contributed to the improvement of our understanding of both the physical and chemical properties of water, ice, and hydrogen‐bonded systems in general. At the heart of this family of in silico techniques lies the crucial idea of computing the many‐body interactions by solving the electronic structure problem “on the fly” as the simulation proceeds, which circumvents the need for pre‐parameterized potential models. In particular, the field of proton transfer in hydrogen‐bonded networks greatly benefits from these technical advances. Here, several systems of seemingly quite different nature and of increasing complexity, such as Grotthuss diffusion in water, excited‐state proton‐transfer in solution, phase transitions in ice, and protonated water networks in the membrane protein bacteriorhodopsin, are discussed in the realms of a unifying viewpoint.
Freestanding Polyelectrolyte Films as Sensors for Osmotic Pressure
Authors: Nolte Marc , Dönch Ingo , Fery Andreas 
Published: August 2006

AbstractFreestanding ultrathin polyelectrolyte‐multilayer membranes, transferred to topographically structured polydimethylsiloxane (PDMS), are used as mechanical sensors. Due to the membranes′ semipermeability, high‐molecular‐weight molecules can be either entrapped inside them or excluded, thus generating an osmotic pressure. This leads to a deformation. We investigate the deformation as a function of the osmotic pressure and present an analytical theory that fully describes the data. Thus, osmotic pressures can be determined quantitatively. The individual osmotic‐sensitive elements have only microscopic dimensions, and arrays can be easily produced.
Asymmetric biomimetic oxidations of phenols using oxazolidines as chiral auxiliaries: the enantioselective synthesis of (+)‐ and (−)‐dehydrodiconiferyl alcohol
Authors: Bruschi Maurizio , Orlandi Marco , Rindone Bruno , Rummakko Petteri , Zoia Luca 
Published: August 2006

AbstractStereoselective bimolecular radical coupling reactions of phenylpropenoid phenols are described. Evans's 2‐oxazolidinone 11a–d derivatives of ferulic acid were prepared and oxidized to give dimeric benzofuran neolignan structures 12–13a–d in 40–50% overall yields. The chiral phenols were dimerized either enzymatically with hydrogen peroxide and horseradish peroxidase (HRP) or with silver oxide. The enantioselectivity after reductive cleavage of the chiral auxiliaries to give dehydrodiconiferyl alcohol ranged from 18% to 62% enantiomeric excess. The conformational analysis and the activation energy using semiempirical PM3 calculations on the intermediate quinomethides is used to explain the observed stereoselectivity. Copyright © 2006 John Wiley & Sons, Ltd.
Structural and electronic properties of ScSb, ScAs, ScP and ScN
Authors: Tebboune AbdelGhani , Rached Djamel , Benzair AbdelNour , Sekkal Nadir , Belbachir A. H. 
Published: August 2006

AbstractThe structural and electronic properties of ScSb, ScAs, ScP and ScN III–V materials are investigated within a version of the first‐principles full potential linear muffin‐tin orbitals method (FPLMTO) that enables an accurate treatment of the interstitial regions. At high pressure, the transition from rocksalt (B1) to CsCl (B2) structure is found to be possible. The zinc blende phase is also investigated and is found to give a semiconductor behavior with a wide bandgap to all our materials. The latter is direct at X for ScAs, ScSb, ScP. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microscopic evidence of the FFLO state in CeCoIn5 probed by NMR study
Authors: Kumagai K. , Kakuyanagi K. , Saitoh M. , Matsuda Y. , Takashima S. , Nohara M. , Takagi H. 
Published: August 2006

AbstractAn anomalous temperature dependence of 115In‐NMR spectrum is observed in the newly‐discovered high field and low temperature superconducting phase of CeCoIn5. The anomalies near the upper limit of H C 2 are attributed to spatially‐distributed local density of states of quasiparticles. From a simulation with the phenomenological model for the sinusoidally‐modulated superconducting order parameter, the present NMR study provides a microscopic evidence that the Fulde‐Ferrell‐Larkin‐Ovchinnikov (FFLO) state is realized at the high field phase in CeCoIn5. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)