bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Approaches Towards the Asymmetric Synthesis of α,α‐Disubstituted α‐Amino Acids
Authors: Vogt Henning , Braese Stefan 
Published: May 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enzymatic and Chemical Cleavage Methods to Identify Genetic Variation
Authors: Bui Chinh T. , Nicolas Emmanuelle , Sallmann Georgina , Chiotis Maria , Lambrinakos Andreana , Rees Kylee , Trounce Ian , Cotton Richard G. H. , Blakesley Lauryn , Godwin Andrew K. , et al. et al. 
Published: May 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Finite‐element model for creep buckling analysis of beam‐type structures
Authors: Lanc Domagoj , Turkalj Goran , Brnić Josip 
Published: May 2007

AbstractThis paper presents a one‐dimensional finite element for creep buckling analysis of structures comprised of straight and prismatic beam members. Spatial displacements and rotations are allowed to be large while strains are assumed to be small. Material is assumed to be homogenous and isotropic. The corresponding equilibrium equations are formulated in the framework of co‐rotational description, using the virtual work principle. In contrast to conventional co‐rotational formulation, which is linear on element level and unable to model Wagner effect, in this paper an additional nonlinear part of stiffness matrix is evaluated and added to standard elastic stiffness.
Implementation of developed numerical algorithm is demonstrated through few test problems. Copyright © 2007 John Wiley & Sons, Ltd.
Scanning Tunneling Microscopy and Spectroscopy Studies of 4‐Methyl‐ 4′‐(n‐mercaptoalkyl)biphenyls on Au(111)‐(1×1)
Authors: Su Gujin J. , Aguilar‐Sanchez Rocio , Li Zhihai , Pobelov Ilya , Homberger Melanie , Simon Ulrich , Wandlowski Thomas 
Published: May 2007

Abstract4‐Methyl‐4′‐(n‐mercaptoalkyl)biphenyl (CH3C6H4C6H4(CH2)nSH, n=3–6, BPn) monolayers assembled on Au(111)‐(1×1) in 1,3,5,‐trimethylbenzene (TMB) at various temperatures are studied by scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). High resolution STM images reveal that BP3 and BP5 form a (${\sqrt 3 }$×2${\sqrt 3 }$) repeating motif superimposed on a temperature‐dependent Moire pattern. BP4 and BP6 adlayers are characterized by a coexisting (2${\sqrt 3 }$×5${\sqrt 3 }$) majority phase and a temperature‐dependent (3×p${\sqrt 3 }$) minority phase. Assembly at 60 °C or 90 °C leads to p=5. Compression of the adlayer was found at higher temperatures. Combined with high‐resolution structure experiments, the electronic characteristics of BP3 and BP4 self‐assembled monolayers (SAMs) were studied by monitoring current–distance (iT–Δz) and current–voltage (iT–Ebias) characteristics in TMB employing a gold STM tip|BPn|Au(111)‐(1×1) configuration. The semilogarithmic (iT–Δz) plots yielded three linear regions in the range 10 pA≤iT≤20 μA, which were attributed to the different positions of the STM tip with respect to the molecular adlayer (I outside, II in contact with and/or within the adlayer, and III just before the formation of Au–Au nanocontacts). The effective decay constants κeff and the corresponding barrier heights ϕeff decrease with decreasing tip–substrate distance. The iT–Ebias curves at low bias voltages are represented by the Simmons tunneling model. Based on measurements in the high current limit, the electric field strength of the dielectric breakdown was estimated to range between |0.85±0.05|×109 V m−1 and |1.5±0.1|×109 V m−1.
Mechanical Properties of Carbon Nanomaterials
Authors: Hayashi Takuya , Kim Yoong Ahm , Natsuki Toshiaki , Endo Morinobu 
Published: May 2007

AbstractCarbon nanomaterials show a variety of interesting chemical and physical properties. In this Minireview we focus on the mechanical properties of carbon nanomaterilas with emphasis on carbon nanotubes and their composite materials. We introduce some recently developed components made of carbon nanotube composite materials and outline their importance for applications in everyday life.
Evaluation of a single‐platform microcapillary flow cytometer for enumeration of absolute CD4+ T‐lymphocyte counts in HIV‐1 infected Thai patients
Authors: Pattanapanyasat Kovit , Phuang‐Ngern Yuwadee , Lerdwana Surada , Wasinrapee Punneeporn , Sakulploy Natthaga , Noulsri Egarit , Thepthai Charin , McNicholl Janet M. 
Published: May 2007

AbstractBackground:Various assays are used to enumerate peripheral blood absolute CD4+ T‐lymphocytes. Flow cytometry is considered the gold standard for this purpose. However, the high cost of available flow cytometers and monoclonal antibody reagents make it difficult to implement such methods in the resource‐poor settings. In this study, we evaluated a cheaper, recently developed single‐platform microcapillary cytometer for CD4+ T‐lymphocyte enumeration, the personal cell analyzer (PCA), from Guava® Technologies.Methods:CD4+ and CD8+ T‐lymphocyte counts in whole blood samples from 250 HIV‐1 infected Thais were determined, using a two‐color reagent kit and the Guava PCA, and compared with the results obtained with two reference microbead‐based methods from Becton Dickinson Biosciences: the three‐color TruCOUNT™ tube method and the two‐color FACSCount™ method. Statistical correlations and agreements were determined using linear correlation and Bland–Altman analysis.Results:Absolute CD4+ T‐lymphocyte counts obtained using the Guava PCA method highly correlated with those obtained using TruCOUNT method (R2 = 0.95, mean bias +13.1 cells/μl, limit of agreement [LOA] −101.8 to +168.3 cells/μl). Absolute CD8+ T‐lymphocyte counts obtained using the Guava PCA method also highly correlated with those obtained with the two reference methods (R2 = 0.92 and 0.88, respectively).Conclusion:This study shows that the enumeration of CD4+ T‐lymphocytes using the Guava microcapillary cytometer PCA method performed well when compared with the two reference bead‐based methods. However, like the two reference methods, this new method needs substantial technical expertise. © 2007 Clinical Cytometry Society.
Does cyclosporin A affect CCR5 and CXCR4 expression in primary HIV‐1‐infected patients?
Authors: Biswas Priscilla , Galli Andrea , Galli Laura , Din Chiara Tassan , Vecchi Andrea , Malnati Mauro , Lazzarin Adriano , Tambussi Giuseppe 
Published: May 2007

AbstractBackground:CCR5 and CXCR4 are the major coreceptors of HIV required for successful viral entry. No information exists on the effect of cyclosporin A (CsA) on expression of CCR5 and CXCR4. A longitudinal study of the coreceptors' expression in freshly isolated peripheral blood mononuclear cells (PBMC) of patients with primary HIV infection (PHI) was performed.Methods:Patients received highly active antiretroviral therapy (HAART) alone (n = 7) or with CsA (HAART + CsA) (n = 8). Flow cytometric data were analyzed at T0 (baseline), two (T2), six (T6), and twelve (T12) months after therapy initiation.Results:At T0 PHI subjects presented a statistically significant higher count and percentage of CD8+CCR5+ lymphocytes compared to healthy donors (HD) (mean ±± SD, 2,240 ±± 1,998 vs 181 ±± 89 cells/μl). Conversely, CD4+CXCR4+ lymphocytes were less abundant in PHI than in HD (443 ±± 337 vs 673 ±± 339 cells/μl), whereas CD4+CCR5+ lymphocytes were substantially comparable (169 ±± 167 vs 126 ±± 60 cells/μl). In the follow up no differences between HAART and HAART + CsA groups reached statistical significance in CD4 lymphocytes. CD4+CCR5– lymphocytes displayed a rapid recovery after therapy initiation, similarly to the CD4+CXCR4+ subset. In CD8 lymphocytes a statistically significant difference between HAART and HAART + CsA patients occurred at T2 when HAART + CsA patients presented a lower absolute count of the CD8+CXCR4+ subset compared to the HAART group. The major change after therapy initiation in all PHI patients was a striking drop of CD8+CCR5+ lymphocytes; moreover, the CD8+CXCR4– subset behaved similarly. The decrement of CD8+CCR5+ lymphocytes paralleled the decline of viremia and CD8+CD38+ lymphocytes, with the sharpest slope at T2. Conversely, RANTES levels increased at T2 and remained elevated during the follow up.Conclusions:CsA cotreatment in PHI patients appears not to substantially modify HIV coreceptors' expression in PBMC. However, this novel piece of information should be used with caution, since this was not a randomized study between the HAART and the HAART + CsA groups. © 2007 Clinical Cytometry Society
Bacillus subtilis spores: A novel microparticle adjuvant which can instruct a balanced Th1 and Th2 immune response to specific antigen
Authors: Barnes Andrew G. C. , Cerovic Vuk , Hobson Philip S. , Klavinskis Linda S. 
Published: May 2007

AbstractThere is a current need for safe, cheap, and effective vaccine adjuvants, to combine with sub‐unit antigens to enhance their immunogenicity. In this study we have used probiotic Bacillus subtilis spores, known to be safe and fully tolerated by ingestion in man, and explored their ability to influence the magnitude and diversity of immune responses induced against two model antigens, tetanus toxoid fragment C (TT) and ovalbumin (OVA) in mice. The results show that B. subtilis spores not only increased antibody and T cell responses to a co‐administered soluble antigen, but also broadened them, to include both antigen‐specific CD4+ and CD8+ T cell responses as well as complement and non‐complement fixing antibody isotypes. Furthermore, following intranasal immunization, spores augmented specific IgA to co‐administered antigen both in the local respiratory and distal vaginal mucosa, as well as increased antigen‐specific IgG antibody in draining LN and blood. Collectively, these data demonstrate that naturally occurring, non‐pathogenic, non‐commensal spores of B. subtilis both instruct and augment polyvalent immune responses and highlight their clinical potential in future vaccines to generate broad‐based immunity.
CpG DNA stimulates autoreactive immature B cells in the bone marrow
Authors: Azulay‐Debby Hilla , Edry Efrat , Melamed Doron 
Published: May 2007

AbstractPolyclonal activation of developing B cells is an injurious process, because most of these cells are nontolerant and express autoreactive receptors. CpG DNA is a polyclonal activator of mature B cells, but its effect on developing B cells is unclear. We tested whether developing, nontolerant B cells are responsive to mitogenic stimulation by CpG DNA and whether such a stimulus can interfere with the establishment of central tolerance. We found that developing B cells express Toll‐like receptor 9 and undergo a polyclonal response to CpG DNA stimulation, as revealed by proliferation and differentiation to antibody‐producing cells. In vitro and ex vivo experiments revealed that stimulation with CpG DNA protects immature B cells from negative selection imposed by apoptosis and receptor editing and results in the production of autoantibodies. Finally, we found that in vivo administration of CpG DNA activates immature B cells in the bone marrow and suppresses the expression of recombination‐activating genes in a mouse model of central tolerance and receptor editing. These results suggest that mitogenic signals provided by CpG DNA stimulate nontolerant immature B cells in the bone marrow and have the potential to interfere with central tolerance.
Human peritoneal macrophages show functional characteristics of M‐CSF‐driven anti‐inflammatory type 2 macrophages
Authors: Xu Wei , Schlagwein Nicole , Roos Anja , van den Berg Timo K. , Daha Mohamed R. , van Kooten Cees 
Published: May 2007

AbstractWe have recently shown that in vitro polarized M‐CSF‐driven anti‐inflammatory macrophages (MΦ2) have the unique capacity to preferentially bind and ingest early apoptotic cells. However, these data are based on in vitro polarized cells and it is unclear whether MΦ2‐like cells exist in vivo. Here we used CD163 as a cell surface marker to distinguish MΦ2 from the pro‐inflammatory MΦ1. We show that human peritoneal MΦ (pMΦ) freshly isolated from patients on peritoneal dialysis have the phenotypical characteristics of MΦ2, including CD163 surface expression and lack of CD16. Like MΦ2, pMΦ have the capacity for endocytosis and macropinocytosis, are able to preferentially bind and ingest early apoptotic cells, and produce large amounts of IL‐10 upon stimulation with LPS. Moreover, upon LPS stimulation both pMΦ and MΦ2 down‐regulate CD86, resulting in a reduced capacity to stimulate proliferation of allogeneic T cells and an inhibition of Th1 cytokine release of these T cells. Our data provide the evidence for the first time that in vitro polarized MΦ2 exist in vivo, and human pMΦ resemble the anti‐inflammatory MΦ2. We propose that pMΦ have the potential to maintain an anti‐inflammatory condition in the peritoneal cavity.
Role of TGF‐β and PGE2 in T cell responses during Plasmodium yoelii infection
Authors: Ocaña‐Morgner Carlos , Wong Kurt A. , Lega Flavia , Dotor Javier , Borras‐Cuesta Francisco , Rodriguez Ana 
Published: May 2007

AbstractDuring an acute blood‐stage malaria infection, T cell responses to malaria and other bystander antigens are inhibited. Plasmodium infection induces strong cytokine responses that facilitate parasite clearance but may interfere with T cell functions, as some of the soluble immune mediators induced are also general inhibitors of T cell responses. Using a malaria mouse model, we have analyzed the cytokines produced by dendritic cells in response to P. yoelii infection that have potential T cell inhibitory activity. We found that during acute infection DC migrate to the spleen and secrete TGF‐β, prostaglandin E2 (PGE2) and IL‐10. We have analyzed the role of these general T cell inhibitors in a particular T cell response of evident importance in malaria infections: the CD8+ T cells generated against the liver‐stage of the disease. During blood‐stage infection, inhibition of the activity of TGF‐β and PGE2 restores the CD8+ T cell responses generated by sporozoites, increasing protection against re‐infection. Our findings suggest that the strong cytokine response induced by blood‐stage P. yoelii infection affects host T cell responses, inhibiting protective CD8+ T cells against the liver‐stage of the disease.
Response of seismically isolated buildings considering poundings
Authors: Komodromos Petros , Polycarpou Panayiotis C. , Papaloizou Loizos , Phocas Marios C. 
Published: May 2007

AbstractNumerical simulations and parametric studies have been used to investigate the influence of potential poundings of seismically isolated buildings with adjacent structures on the effectiveness of seismic isolation. Poundings are assumed to occur at the isolation level between the seismically isolated building and the surrounding moat wall. After assessing some common force‐based impact models, a variation of the linear viscoelastic impact model is proposed to avoid tensile impact forces during detachment, while enabling the consideration of permanent plastic deformations at the vicinity of the impact. A large number of numerical simulations of seismically isolated buildings with different characteristics have been conducted under six earthquake excitations in order to investigate the influence of various design parameters and conditions on the peak floor accelerations and interstorey deflections during poundings. The numerical simulations demonstrate that poundings may substantially increase floor accelerations, especially t the base floor where impacts occur. Higher modes of vibration are excided during poundings, increasing the interstorey deflections, instead of retaining an almost rigid‐body motion of the superstructure, which is aimed with seismic isolation. Impact stiffness seems to affect significantly the acceleration response at the isolation level, while the displacement response is more insensitive to the variation of the impact stiffness. Finally, the results indicate that providing excessive flexibility at the isolation system to minimize the floor accelerations may lead to a building vulnerable to poundings, if the available seismic gap is limited. Copyright © 2007 John Wiley & Sons, Ltd.
A new model to analyse the impact of woody riparian vegetation on the geotechnical stability of riverbanks
Authors: Wiel Marco J. Van De , Darby Stephen E. 
Published: May 2007

AbstractWe present a geotechnical stability analysis for the planar failure of riverbanks, which incorporates the effects of root reinforcement and surcharge for mature stands of woody riparian vegetation. The analysis relies on a new method of representing the root distribution in the soil, which evaluates the effects of the vegetation's position on the bank. The model is used in a series of sensitivity analyses performed for a wide range of bank morphological (bank slope and height) and sedimentological (bank cohesion and friction angle) conditions, enabling discrimination of the types of bank environment for which vegetation has an effect on bank stability. The results indicate that woody vegetation elements have a maximal impact on bank stability when they are located at the ends of the incipient failure plane (i.e. at the bank toe or at the intersection of the failure plane with the floodplain) and that vegetation has a greater effect on net bank stability when it is growing on low, shallow, banks comprised of weakly cohesive sediments. However, the magnitude of these effects is limited, with vegetation typically inducing changes (relative to non‐vegetated banks) in simulated factors of safety of less than 5%. If correct, this suggests that the well documented effects of vegetation on channel morphology must be related to alternative process mechanisms (such as the interaction of vegetation with river flows) rather than the mechanical effects of vegetation on bank failure, except in special cases where the equivalent non‐vegetated bank has a highly marginal stability status. Copyright © 2007 John Wiley & Sons, Ltd.
Essential oil composition of Prasium majus L. from Greece
Authors: Basta A. , Tzakou O. , Couladis M. , Yannitsaros A. 
Published: May 2007

AbstractThe essential oils from the aerial parts of Prasium majus (Labiatae), collected in two phenological stages in Greece, were analysed by GC–MS. Thirty‐two compounds were identified, representing 99.8–99.9% of the total oils. The major constituents in sample A were 1‐octen‐3‐ol (20.7%), α‐pinene (14.7%) and linalool (13.8%), while those of sample B were dehydro‐aromadendrene (31.8%), caryophyllene oxide (13.7%) and 1‐octen‐3‐ol (12.4%). Copyright © 2007 John Wiley & Sons, Ltd.
Composition of essential oil, concrete, absolute, wax and headspace volatiles of Murrarya paniculata (Linn.) Jack flowers
Authors: Rout P. K. , Rao Y. R. , Sree A. , Naik S. N. 
Published: May 2007

AbstractMurraya paniculata (Linn) Jack, syn. M. exotica Linn., commonly known as orange jessamine, is grown in gardens for its large clusters of fragrant flowers. Distillation of the fresh flowers in water furnished the essential oil in 0.027% yield. Extraction of the fresh flowers with pentane afforded the concrete (0.78%). Precipitating the waxes from the concrete with methanol gave absolute (0.62%). The chemical composition of essential oil, concrete, absolute and wax were analysed by GC and GC–MS. The components of essential oil in significant amounts were δ‐elemene (1.4%), (E)‐caryophyllene (3.6%), germacrene D (2.7%), (E)‐nerolidol (25.7%), benzyl benzoate (8.1%), phenyl ethyl benzoate (8.0%) and manool (18.7%). The major components in the concrete and absolute, respectively, were phenyl ethyl alcohol (2.9%, 3.0%), indole (0.8%, 1.0%), (E)‐nerolidol (6.5%, 7.0%), benzyl benzoate (5.0%, 6.5%), phenyl ethyl benzoate (8.0%, 8.6%) and manool (25.2%, 27.9%). The methanol‐insoluble wax contained (E)‐nerolidol (2.6%), manool (9.4%) and most of the fatty acids/esters. The composition of the volatile components in the headspace emitted by flowers still on the branch (live flowers) and also by the picked flowers was determined by HS–SPME on a PDMS fibre and these results are also presented. The major components found in the headspace were linalool, indole, (E)‐caryophyllene, germacrene D, bicyclogermacrene and (E,E)‐α‐farnesene. Copyright © 2007 John Wiley & Sons, Ltd.
Determination of flavour profile in Iranian fragrant rice samples using cold‐fibre SPME–GC–TOF–MS
Authors: Ghiasvand Ali Reza , Setkova Lucie , Pawliszyn Janusz 
Published: May 2007

AbstractA newly developed cold‐fibre solid‐phase microextraction (CF–SPME) device, as a powerful system for collection and concentration of volatile compounds, coupled to a gas chromatography time‐of‐flight mass spectrometer (GC–TOF–MS) system, equipped with a multi‐channel ion detector and a deconvolution software, was investigated for the analysis of volatile flavour compounds in the headspace of rice samples. The proposed combination provided a powerful system for easy and rapid screening of a wide range of flavours in fragrant rice samples. Based on four target analytes, including 2‐acetyl‐1‐pyrroline as a key odorant compound, different experimental parameters were optimized. The effect of the fibre composition, moisture present in the matrix, extraction temperature and time and desorption time were investigated. Nine Iranian and two Indian fragrant rice varieties were analysed using CF–SPME and the results were compared with commercial SPME fibres. The results revealed that uncooked rice samples can be successfully analysed even as dry kernels, without adding water, utilizing the fully automated CF–SPME–GC–TOF–MS. When using PDMS fibre, a clearly distinguishable peak was seen for 2‐acetyl‐1‐pyrroline by simultaneous cooling of the fibre and heating of rice matrices as dry whole grains. Copyright © 2007 John Wiley & Sons, Ltd.
Aroma volatile constituents of Colombian varieties of mango (Mangifera indica L.)
Authors: Quijano Clara E. , Salamanca Guillermo , Pino Jorge A. 
Published: May 2007

AbstractThe volatile components of nine Colombian mango varieties were investigated by means of simultaneous distillation–extraction, GC and GC–MS. One hundred and forty‐five compounds were identified, of which eight were found for the first time in mango fruit. The total concentration of volatiles was ca. 17–75 mg/kg fresh fruit. Terpene hydrocarbons were the major volatiles of all varieties, the dominant terpenes being δ‐3‐carene (Haden, Irwin, Manila and Tommy Atkins), α‐pinene (Hilacha and Vallenato), α‐phellandrene (Van Dyke) and terpinolene (Yulima), while no dominant terpene was found in the Springfield variety. Other qualitative and quantitative differences between the varieties were demonstrated. Copyright © 2007 John Wiley & Sons, Ltd.