bluuebunny/crossref_metadata_2025 huggingface dataset:
Unique Signaling Properties of CTAR1 in LMP1-Mediated Transformation
Authors: Mainou Bernardo A. , Everly David N. , Raab-Traub Nancy
Published: July 2007

The Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene is considered the EBV oncogene as it is necessary for EBV-mediated transformation of B lymphocytes and itself transforms rodent fibroblasts. LMP1 activates the NF-κB, phosphatidylinositol 3-kinase (PI3K)-Akt, mitogen-activated protein kinase, and Jun N-terminal protein kinase signaling pathways through its two signaling domains, carboxyl-terminal activating regions 1 and 2 (CTAR1 and CTAR2). CTAR1 and CTAR2 induce signal transduction pathways through their direct (CTAR1) or indirect (CTAR2) recruitment of tumor necrosis factor receptor-associated factors (TRAFs). CTAR1 is necessary for LMP1-mediated transformation as well as activation of PI3K signaling and induction of cell cycle markers associated with G
1
/S transition. In this study, activation of PI3K-Akt signaling and deregulation of cell cycle markers were mapped to the TRAF-binding domain within CTAR1 and to the residues between CTAR1 and CTAR2. LMP1 CTAR1 also activated the MEK1/2-extracellular signal-regulated kinase 1/2 signaling pathway, and this activation was necessary for LMP1-induced transformation of Rat-1 fibroblasts. Dominant-negative forms of TRAF2 and TRAF3 inhibited but did not fully block LMP1-mediated transformation. These findings identify a new signaling pathway that is uniquely activated by the TRAF-binding domain of LMP1 and is required for transformation.
Sorption and diffusion of volatile organic compounds through two thermally treated drill mud wastes
Authors: Carignan Marie-Pierre , Lake Craig B
Published: July 2007

Onshore thermal treatment of offshore drilling mud waste generates a mineral by-product, referred to in this paper as thermally treated drill mud waste (TTDMW). Environmental regulations can result in the generation of significant quantities of this material, and hence it would be beneficial from a sustainability perspective to identify a value-added recycling use for this material. Recycling TTDMW into a primary compacted soil barrier system for municipal solid waste landfills represents one such possible reuse. It is hypothesized that residual amounts of organoclays and organic carbon in the TTDMWs will act as a beneficial sorbent to low levels of volatile organic compounds (VOCs) often found in municipal solid waste leachate. To assess this hypothesis, two different TTDMW materials (from Nova Scotia and the United Kingdom) were subjected to batch and diffusion testing to assess VOC sorption. It is shown that partitioning coefficient (Kd) values obtained from diffusion testing were generally lower than those obtained from batch testing. Contaminant migration modelling of a hypothetical TTDMW barrier system using measured VOC sorption levels is presented in the paper to provide some relevance to the results obtained.Key words: drill mud waste, sorption, VOC, diffusion, landfill liner.
Natural selection for ozone tolerance in Populustremuloides
Authors: Berrang P. , Karnosky D. F. , Mickler R. A. , Bennett J. P.
Published: July 2007

Relative ozone sensitivity was evaluated among populations of Populustremuloides Michx. from each of five national parks differing in air quality. Eleven to 15 clones from each population were greenhouse grown and fumigated twice during 2 years of screening, each time with 180 ppb ozone for 6 h. The average injury for clones was significantly less for the most polluted park than for the least polluted park and there was a high negative association between average injury and ambient ozone levels. Differences in ozone sensitivity among clones within populations were highly significant and larger than differences among populations. These results suggest natural selection for tolerance in P. tremuloides may have occurred in some areas of eastern United States.
Evidence for nonstomatal inhibition of net photosynthesis in rapidly dehydrated shoots of Populus
Authors: Scarascia-Mugnozza G. , Hinckley T. M. , Stettler R. F.
Published: July 2007

Results are presented on the decline of net photosynthesis during the application of rapid water stress to excised shoots of different Populus L. clones. Six clones were selected from the species Populustrichocarpa Torr. & Gray, Populusdeltoides Bartr., and from the hybrid Populustrichocarpa × Populusdeltoides, taking into account the differences in stomatal behaviour between and within these species. The two most productive P. trichocarpa clones and the hybrid clone, characterized by a reduced ability to close stomata during leaf desiccation, showed, nevertheless, a sharp reduction of net photosynthesis at water potentials lower than −1.5 MPa. In contrast, the inhibition of net assimilation in the P. deltoides clone, caused by water stress, was accompanied by a reduction in stomatal conductance. In all studied clones the decrease in net photosynthetic rate followed closely the point of turgor loss of the leaves, indicating a possible relationship between nonstomatal inhibition of photosynthesis and protoplast volume shrinkage.
Lodgepole pine and white spruce crown fuel weights predicted from height and crown width
Authors: Johnson Allen F. , Woodard Paul M. , Titus Stephen J.
Published: July 2007

Equations were developed to predict the ovendry weight of the total crown, live crown, foliage, and the roundwood diameter classes of <0.5, 0.5–1.0, 1.0–3.0, 3.0–5.0, 5.0–7.0, 7.0–10.0 cm for lodgepole pine (n = 27) and white spruce (n = 23) occurring in Alberta, Canada. The nonlinear allometric model using total tree height and a measure of crown width provided high R2 and low SEE values. This precision could not be duplicated when total tree height was used as the only independent variable. Our results suggest the possibility of using tree height and crown width measured from aerial photographs to estimate standing live and dead fuel loadings in undisturbed forest stands.
Frequency modulation of renal myogenic autoregulation by perfusion pressure
Authors: Wang Xuemei , Loutzenhiser Rodger D. , Cupples William A.
Published: July 2007

Recent studies of renal autoregulation have shown modulation of the faster myogenic mechanism by the slower tubuloglomerular feedback and that the modulation can be detected in the dynamics of the myogenic mechanism. Conceptual and empirical considerations suggest that perfusion pressure may modulate the myogenic mechanism, although this has not been tested to date. Here we present data showing that the myogenic operating frequency, assessed by transfer-function analysis, varied directly as a function of perfusion pressure in the hydronephrotic kidney perfused in vitro over the range from 80 to 140 mmHg. A similar result was obtained in intact kidneys in vivo when renal perfusion pressure was altered by systemic injection of NG-nitro-l-arginine methyl ester (l-NAME). When perfusion pressure was not allowed to increase, l-NAME did not affect the myogenic operating frequency despite equivalent reduction of renal vascular conductance. Blood-flow dynamics were assessed in the superior mesenteric artery before and after l-NAME. In this vascular bed, the operating frequency of the myogenic mechanism was not affected by perfusion pressure. Thus the operating frequency of the renal myogenic mechanism is modulated by perfusion pressure independently of tubuloglomerular feedback, and the data suggest some degree of renal specificity of this response.
Hypoxic ventilatory response during light and dark periods and the involvement of histamine H1 receptor in mice
Authors: Ohshima Yasuyoshi , Iwase Michiko , Izumizaki Masahiko , Ishiguro Takashi , Kanamaru Mitsuko , Nakayama Hideaki , Gejyo Fumitake , Homma Ikuo
Published: July 2007

Ventilation oscillates throughout a day in parallel with oscillations in metabolic rate. Histamine affects ventilation and the balance of the energy metabolism via H1 receptors in the brain. We tested the hypothesis that the ventilatory response to hypoxia varies between light and dark periods and that histamine H1 receptors are required for the circadian variation, using wild-type (WT) and histamine H1 receptor knockout (H1RKO) mice. Mice were exposed to hypoxic gas (7% O2 + 3% CO2 in N2) during light and dark periods. Ventilation initially increased and then declined. In WT mice, minute ventilation (V̇e) during hypoxia was higher in the dark period than in the light period, which was an upward shift along with the baseline ventilation. Hypoxia decreased the metabolic rate, whereas O2 consumption (V̇o2) and CO2 excretion were higher in the dark period than in the light period. However, in H1RKO mice, changes in V̇e during hypoxia between light and dark periods were minimal, because V̇e was increased relative to V̇o2, particularly in the light period. In H1RKO mice, the HCO3− concentration and base excess values were increased in arterial blood, and the level of ketone bodies was increased in the serum, indicating that metabolic acidosis occurred. Respiratory compensation takes part in the V̇e increase relative to V̇o2 during hypoxia. These results suggested that changes in V̇e during hypoxia vary between light and dark periods and that H1 receptors play a role in circadian variation in V̇e through control of the acid-base status and metabolism in mice.
Study on resistance welding of metallic sandwich panel
Authors: Kim J.-B. , Lee S.-M. , Na S.-J.
Published: July 2007

Inner structured and bonded (ISB) panel, a type of metallic sandwich panel, consists of two thin skin plates bonded to a micropatterned inner structure. It has an overall thickness of 1–3 mm and attractive properties, such as ultralight weight, high efficiency in stiffness to weight and strength to weight ratios. In this paper, a new joining process using resistance welding is developed for joining ISB panels. Electrodes with curved surface are applied to join the two skin plates and micropatterned inner structure, while two stoppers are used to keep a gap between the electrodes during welding. Owing to this gap, the inner structure shape is maintained without damage. Current, welding time and electrode gap were selected as the process parameters. This process is simpler and more suitable for mass production than previous processes for joining the panel. Appropriate welding conditions were studied by measuring the tensile load with respect to variations in welding time and electrode gap.
Factors influencing current density distribution and current crowding in flip chip solder joints
Authors: Yu C. , Lu H. , Fan R. Z. , Li S. M.
Published: July 2007

Three-dimensional simulations were carried out to investigate the current density distribution in the flip chip solder joints. There were two kinds of factors influencing the current density distributions in the flip chip solder joints, i.e. the structural geometry and the material's properties. It is found that increasing the dimensions of trace and under bump metallisation (UBM) and/or decreasing the resistivity of trace, UBM and solder bump are beneficial to relieve the current crowding. The experimental results also show that microvoids were formed at the cathode side of Cu/Sn–37Pb/Cu and narrower Cu trace Cu/Sn–3.0Ag–0.5Cu/Cu structures, but not at that structure with a wider Cu trace under the same test conditions. However, increasing the dimensions of the solder joint unrestrictedly departs from the miniaturisation trend of integrated circuit. But this difficulty can be overcome by optimising the above factors synthetically with finite element modelling method. The results also partly account for a better electromigration (EM) resistant ability of Sn–Ag–Cu than Sn–Pb solder.
New Stability Index for Short Circuit Transfer Mode in GMAW Process using Acoustic Emission Signals
Authors: Roca A. Sánchez , Fals H. Carvajal , Fernández J. Blanco , Macías E. Jiménez , Adán F. Sanz
Published: July 2007

A new index for the analysis of stability of GMAW processes taking as a base the acoustic emission generated by the arc during the short circuit metal transfer is presented in the present work. The incidence of parameters of process is analysed in the indices of the acoustic emission signal, as well as its influence on the stability, evaluated through a new proposed index. The results obtained allowed having a relationship between acoustic signals and arc voltage signals, and demonstrated the validity of proposed index of acoustic emission for analysis of stability of GMAW process. The obtained results were then compared with other classic stability analysis methods based on statistical analysis of temporal signals of arc voltage. Finally a statistical analysis for the validation of the obtained experimental results was carried out. As a result of the investigation, the effectiveness of the method proposed as a new way for the analysis of stability is demonstrated. The research can contribute towards a new standard to evaluate the stability in welding processes.
Effect of two step heating process on joint microstructure and properties during transient liquid phase bonding
Authors: Wang X. G. , Li X. G. , Yan Q.
Published: July 2007

45MnMoB steel was joined by transient liquid phase (TLP) bonding using three two step heating processes. The joining area was first heated up to 1250°C and kept for 5 s, and then cooled down to 1210, 1220 and 1230°C named second holding temperature respectively and kept for 120 s. The interface morphology of the bond made using two step heating process was also compared with that of conventional TLP bond at a constant temperature. The results show that two step heating process can produce a cellular interface at the initial stage, which is different from the planar interfaces associated with conventional TLP bonding. No bond interface can be found in the final joint by two step heating process and the microstructure of joint is similar to that of base metal. With the increase in second holding temperature, oxide scale particles and porosities in the bond region are decreased noticeably both in size and amount, and the bond strength is increased. The bond fails at the base metal and no failure occurs when the joint is tensioned and bent to 180° at 1250 and 1230°C respectively. Therefore, two step heating process can produce a homogenous joint, free of bond interface and identical in composition and properties to that of the base metal.
Overexpressed TP73 induces apoptosis in medulloblastoma
Authors: Castellino Robert C , De Bortoli Massimiliano , Lin Linda L , Skapura Darlene G , Rajan Jessen A , Adesina Adekunle M , Perlaky Laszlo , Irwin Meredith S , Kim John YH
Published: July 2007

Background

Medulloblastoma is the most common malignant brain tumor of childhood. Children who relapse usually die of their disease, which reflects resistance to radiation and/or chemotherapy. Improvements in outcome require a better understanding of the molecular basis of medulloblastoma growth and treatment response. TP73 is a member of the TP53 tumor suppressor gene family that has been found to be overexpressed in a variety of tumors and mediates apoptotic responses to genotoxic stress. In this study, we assessed expression of TP73 RNA species in patient tumor specimens and in medulloblastoma cell lines, and manipulated expression of full-length TAp73 and amino-terminal truncated ΔNp73 to assess their effects on growth.

Methods

We analyzed medulloblastoma samples from thirty-four pediatric patients and the established medulloblastoma cell lines, Daoy and D283MED, for expression of TP73 RNA including the full-length transcript and the 5'-terminal variants that encode the ΔNp73 isoform, as well as TP53 RNA using quantitative real time-RTPCR. Protein expression of TAp73 and ΔNp73 was quantitated with immunoblotting methods. Clinical outcome was analyzed based on TP73 RNA and p53 protein expression. To determine effects of overexpression or knock-down of TAp73 and ΔNp73 on cell cycle and apoptosis, we analyzed transiently transfected medulloblastoma cell lines with flow cytometric and TUNEL methods.

Results

Patient medulloblastoma samples and cell lines expressed full-length and 5'-terminal variant TP73 RNA species in 100-fold excess compared to non-neoplastic brain controls. Western immunoblot analysis confirmed their elevated levels of TAp73 and amino-terminal truncated ΔNp73 proteins. Kaplan-Meier analysis revealed trends toward favorable overall and progression-free survival of patients whose tumors display TAp73 RNA overexpression. Overexpression of TAp73 or ΔNp73 induced apoptosis under basal growth conditions in vitro and sensitized them to cell death in response to chemotherapeutic agents.

Conclusion

These results indicate that primary medulloblastomas express significant levels of TP73 isoforms, and suggest that they can modulate the survival and genotoxic responsiveness of medulloblastomas cells.
Effects of Organic and Conventional Practices on Weed Control in a Perennial Cropping System
Authors: Baumgartner Kendra , Steenwerth Kerri L. , Veilleux Lissa
Published: July 2007

Vineyard weed communities were examined under the influence of an organic weed control practice, soil cultivation with a Clemens cultivator, and applications of the herbicide glyphosate. Experimental treatments (winter–spring glyphosate, spring cultivation, fall–spring cultivation, fall cultivation–spring glyphosate) were carried out in a California wine grape vineyard for 3 yr. Cultivation alone was not as effective as glyphosate, based on lower weed biomass in the glyphosate-only treatment in 2 of 3 yr. However, given that two passes with the Clemens cultivator decreased weed biomass relative to one pass, it is possible that additional passes could bring about further reductions. Pairing fall cultivation with glyphosate was as effective at reducing weed biomass as two glyphosate applications in 2 of 3 years, suggesting that substituting a glyphosate application with cultivation may be an effective method of reducing herbicide use in vineyards. Canonical correspondence analysis revealed significant treatment effects on community structure. Weed composition in the spring cultivation treatment was significantly different from that of all other treatments. Based on our findings of high relative abundance of field bindweed and sowthistle species, which are problematic vineyard weeds that grow into the vine canopy and disrupt canopy management practices, it is possible that either the presence of soil disturbance or the absence of herbicides favored these species.
In situ cyclization reactions during the preparation of high‐performance methacrylic acid/acrylonitrile/acrylamide ternary copolymer foam
Authors: Liu Tie‐Min , Zhang Guang‐Cheng , Liang Guo‐Zheng , Chen Ting , Zhang Cui
Published: July 2007

A new high‐performance methacrylic acid/acrylonitrile/acrylamide ternary copolymer foam was prepared by radical bulk copolymerization, and the reaction mechanism of in situ cyclization taking place during copolymer foaming as well as the heat treatment was examined too. Then, the crucial mechanism was validated via optical microscopy, infrared absorption spectroscopy (Fourier transform infrared), differential thermal analysis (differential scanning calorimetry), and thermogravimetric analysis. The results showed a weak exothermic peak at 149.17°C and a strong endothermic peak at 270.85°C in differential scanning calorimetry curves of the methacrylic acid/acrylonitrile/acrylamide copolymer after the foaming and heat treatment at 160°C for 2 h and at 200°C for 2 h. The peak temperature of the differential thermogravimetry curve was 175.87°C, whereas the weight‐loss rate was less at 276.58°C in the thermogravimetry curves. In the case of the Fourier transform infrared curves, the OH absorption peak at 930–970 and 1480 cm−1 weakened, and the CN absorption peak of the imide increased. The >CO absorption peak at 1700 cm−1 occurred as an excursion phenomenon toward the low‐frequency field; at the same time, the second absorption peak increased. Furthermore, the CN absorption peak at 2240 cm−1 weakened, and a new CN absorption band appeared. All these data revealed that in situ cyclizations had taken place in the copolymer molecule chains, so some rigid ring structures appeared in the copolymer molecule chains, such as six‐membered imide rings and ladder polymer structures. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Crystal form and orientation of isotactic polypropylene samples prepared by vibration‐injection molding
Authors: Zhang Jie , Zeng Tai , Zhu Ji , Lei Yanwei , Shen Kaizhi , Fu Qiang
Published: July 2007

A vibration–injection molding equipment was developed to prepare isotactic polypropylene injection samples to investigate their crystal form and orientation. Wide‐angle X‐ray scattering experiments (WAXD) were conducted in two modes: theta–theta mode and tube‐fixed mode. Through vibration–injection molding, in additional to α form, β form, or γ form can be obtained under different conditions. At high melt temperature (230), β‐PP can be induced and the core of the sample contains more β‐PP than the surface. At low melt temperature (190), γ‐PP can be induced and the core and the surface of the sample contain approximate same proportion of γ‐PP. Pole figures show that α‐PP of a static sample just orientates slightly along M direction, while that of vibration samples orientate much stronger. The orientation of the normal of (040)α plane of the sample obtained at T = 230°C, f = 0.5 Hz, and Pv = 75MPa is preferred in M direction, and the orientation of the normal of (040)α plane of the sample obtained at T = 190°C, f = 1.5 Hz, and Pv= 35 MPa is preferred in N direction. β‐PP and γ‐PP do not show obvious orientation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effects of SiO2 nanoparticles on the performance of carboxyl‐randomized liquid butadiene–acrylonitrile rubber modified epoxy nanocomposites
Authors: Zeng Minfeng , Sun Xudong , Yao Xiandong , Ji Genzhong , Chen Ning , Wang Baoyi , Qi Chenze
Published: July 2007

The effects of SiO2 nanoparticles on the performance of carboxyl‐randomized liquid butadiene–acrylonitrile rubber (CRBN) modified epoxy resin (EP) nanocomposites were studied. With the addition of an appropriate amount of SiO2 (2%) to EP/CRBN (95/5), the nanocomposites could achieve the desired impact strength and modulus. The morphology of the nanocomposites was studied with scanning electron microscopy and transmission electron microscopy. The nanocomposites showed a three‐phase system; both the rubber particles and SiO2 nanoparticles showed uniform dispersions in the EP matrix, with their phases all nanosized. A good correlation between the free‐volume hole radius and mechanical properties was found. The introduction of a small amount of nanoparticles (both rubber and SiO2) into EP led to the formation of interactions between the EP and nanoparticles. The interactions restricted the segment motion and the mobilization of the EP chains and then reduced the free‐volume concentration in the amorphous region of EP. The fact that the average free‐volume hole radius of EP/CRBN was larger than that of pure EP was mainly attributed to the contribution of the larger size of the free‐volume holes within the rubber phase. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
New bleeding model of additives in a polypropylene film under atmospheric pressure II
Authors: Wakabayashi Makoto , Kohno Takayuki , Kimura Tokutaro , Tamura Satoshi , Endoh Masahiko , Ohnishi Satoru , Nishioka Toshikatsu , Tanaka Yoshikatsu , Kanai Toshitaka
Published: July 2007

Many additives are commercially used to add more favorable qualities to films. The bleeding process by which the additive in a film comes to the surface is considered. A new bleeding model of additives in a polypropylene film under atmospheric pressure was investigated. Solubility and diffusion are found to be important for explaining this bleeding process. It was found that the experimental results were explained more precisely by assuming a two‐step transport process between the crystalline regions and the amorphous ones. The solubilities and diffusion coefficients of UV‐stabilizers such as 2‐(2H‐benzotriazol‐2‐yl)‐4‐(1,1,3,3‐tetramethylbutyl)phenol and 2‐(2H‐benzotriazol‐2‐yl)‐4‐methylphenol were determined at 40°C. The difference between the saturation solubilities and the diffusion coefficients of UV‐stabilizers was discussed by comparing with the results of molecular dynamics (MD) simulation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Bottle‐to‐bottle recycling of PET via nanostructure formation by melt intercalation in twin screw compounder: Improved thermal, barrier, and microbiological properties
Authors: Hamzehlou Sh. , Katbab A. A.
Published: July 2007

Attempts have been made to modify the properties of the injection processing‐scraped PET (denoted as RPET) via intercalation with different levels of organically modified nanoclay (montmorillonite) by melt blending in a corotating twin screw compounder. The clay platelets dispersion state has been qualitatively correlated with the melt linear viscoelastic as well as tensile and barrier properties of the prepared nanocomposites. Oxygen permeation of the nanocomposite PET films showed significant reduction compared with the pristine PET polymer. All the PET/nanoclay composites exhibited no bacterial growth, with no potentiality to generate acetaldehyde, as measured by GC/Mass analyzer. X‐ray diffractometry and transmission electron microscopy performed on the scraped PET/organoclay nanocomposite samples showed increase in d001 spacing of the clay layers and their dispersion throughout the PET matrix. Differential scanning calorimetry analysis showed higher crystallization temperature as well as crystallization enthalpy (ΔHc) for the nanocomposite samples, compared with the unprocessed virgin PET. The RPET nanocomposite samples composed of 3 and 5% of nanoclay exhibited enhanced melt elastic modulus and pseudosolid‐like behavior at low shear frequencies measured by rheomechanical spectroscopy than the unfilled pristine‐scraped PET, indicating the formation of nanoscopic network structure by the clay platelets, which leads to the development of nanostructured resin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
The morphology and photoelectronic properties of poly(9,9′‐dioctylfluorene)/ethyl‐cyanoethyl cellulose blends
Authors: He Benqiao , Li Jing , Bo Zhishan , Huang Yong
Published: July 2007

The morphology and photoelectronic properties of blend films of poly(9,9′‐dioctylfluorine) (PF) and ethyl–cyanoethyl cellulose [(E‐CE)C] were investigated. It was found that the morphology of the blends was changed with the blend composition. The lateral phase separation was observed in submicron scale, and a nanoscale vertical phase separation occurred with enrichment of the (E‐CE)C at the surface of the blend films. The photoluminescent spectra of the blend films are blue‐shifted with the increase of the (E‐CE)C. The photoelectronic properties of the blends varied with the morphology of the blends. In the electroluminescent device, the turn‐on voltage was almost identical for the device with 50% or above 50 wt % PF in blend films and markedly improved for the device with only 25 wt % PF. The external quantum efficiency of the device fabricated with 75% PF is the highest among the device fabricated with the PF/(E‐CE)C blend films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Preparation and properties of plasticized starch/multiwalled carbon nanotubes composites
Authors: Cao Xiaodong , Chen Yun , Chang Peter R. , Huneault Michel A.
Published: July 2007

In this work we have studied the utilization of multiwalled carbon nanotubes (MWCNTs) as filler‐reinforcement to improve the performance of plasticized starch (PS). The PS/MWCNTs nanocomposites were successfully prepared by a simple method of solution casting and evaporation. The morphology, thermal behavior, and mechanical properties of the films were investigated by means of scanning electron microscopy, wide‐angle X‐ray diffraction, differential scanning calorimetry, and tensile testing. The results indicated that the MWCNTs dispersed homogeneously in the PS matrix and formed strong hydrogen bonding with PS molecules. Compared with the pure PS, the tensile strength and Young's modulus of the nanocomposites were enhanced significantly from 2.85 to 4.73 MPa and from 20.74 to 39.18 MPa with an increase in MWCNTs content from 0 to 3.0 wt %, respectively. The value of elongation at break of the nanocomposites was higher than that of PS and reached a maximum value as the MWCNTs content was at 1.0 wt %. Besides the improvement of mechanical properties, the incorporation of MWCNTs into the PS matrix also led to a decrease of water sensitivity of the PS‐based materials. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Dielectric properties of layered silicate‐reinforced natural and polyurethane rubber nanocomposites
Authors: Psarras G. C. , Gatos K. G. , Karger‐Kocsis J.
Published: July 2007

Natural rubber (NR), polyurethane rubber (PUR), and NR/PUR‐based nanocomposites were prepared by adding a pristine synthetic layered silicate (LS; sodium fluorohectorite) in 10 parts per hundred parts rubber, following the latex compounding route. The dispersion of the LS latices in the composites was studied by means of X‐ray diffraction (XRD) and transmission electron microscopy (TEM). The morphology‐dependent dielectric properties of the produced nanocomposites were examined using broadband dielectric spectroscopy (BDS) at ambient temperature. Besides the glass/rubber transition of the polymer matrices, interfacial polarization (IP) is evident in the produced nanocomposites. The α‐relaxation, as well as the β‐mode, in the PUR‐containing nanocomposites proved to be less affected by the presence of LSs. The obtained experimental data suggest that the LS is more compatible with and thus better intercalated by the PUR than by the NR which was prevulcanized in this case. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Self‐Assembled Single‐Walled Carbon Nanotube:Zinc–Porphyrin Hybrids through Ammonium Ion–Crown Ether Interaction: Construction and Electron Transfer
Authors: D'Souza Francis , Chitta Raghu , Sandanayaka Atula S. D. , Subbaiyan Navaneetha K. , D'Souza Lawrence , Araki Yasuyuki , Ito Osamu
Published: July 2007

An ammonium ion–crown ether interaction has been successfully used to construct porphyrin–single‐walled carbon nanotube (SWNT) donor–acceptor hybrids. The [18]crown‐6 to alkyl ammonium ion binding strategy resulted in porphyrin–SWNT nanohybrids that are stable and soluble in DMF. The porphyrin–SWNT hybrids were characterized by spectroscopic, TEM, and electrochemical techniques. Both steady‐state and time‐resolved emission studies revealed efficient quenching of the singlet excited state of the porphyrins and free‐energy calculations suggested that electron‐transfer quenching occurred. Nanosecond transient absorption spectral results supported the charge‐separation quenching process. Charge‐stabilization was also observed for the nanohybrids in which the lifetime of the radical ion pairs was around 100 ns. The present nanohybrids were also used to reduce the hexyl viologen dication (HV2+) and to oxidize 1‐benzyl‐1,4‐dihydronicotinamide in solution in an electron‐pooling experiment. Accumulation of the radical cation (HV.+) was observed in high yields, which provided additional proof for the occurrence of photoinduced charge separation. The present study demonstrates that a hydrogen‐bonding motif is a successful self‐assembly method to build SWNTs bearing donor–acceptor nanohybrids, which are useful for light‐energy harvesting and photovoltaic applications.
Zinc Selenium Oxochloride, β‐Zn2(SeO3)Cl2, a Synthetic Polymorph of the Mineral Sophiite.
Authors: Johnsson Mats , Toernroos Karl W.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
How Carbon Affects Hydrogen Desorption in NaAlH4 and Ti‐Doped NaAlH4.
Authors: Cento C. , Gislon P. , Bilgili M. , Masci A. , Zheng Q. , Prosini P. P.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Three Novel Phases in the Sm—Co—Ga System. Syntheses, Crystal and Electronic Structures, and Electrical and Magnetic Properties.
Authors: Jia YongZhong , Belin Claude , Tillard Monique , Lacroix‐Orio Laurence , Zitoun David , Feng GuoHua
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of cis‐3,4‐Diarylpiperidines and cis‐3,4‐Diaryltetrahydropyrans.
Authors: Chang Meng‐Yang , Lin Chun‐Yu , Hung Ching‐Yi
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Aza‐Michael Addition of Amines to Activated Alkenes Catalyzed by Silica Supported Perchloric Acid under a Solvent‐Free Condition.
Authors: Mukherjee Chinmoy , Misra Anup Kumar
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Direct Synthesis of Weinreb Amides from Carboxylic Acids Using Triphosgene.
Authors: Han Ki‐Jong , Kim Misoo
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
K5CoW12O40×3H2O: Highly Efficient Heterogeneous Catalyst for the Synthesis of α‐Aminonitriles.
Authors: Rafiee E. , Azad A. , Joshaghani M.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structural Modifications of (1S,3S)‐3‐Amino‐4‐difluoromethylenecyclopentanecarboxylic Acid, a Potent Irreversible Inhibitor of GABA Aminotransferase.
Authors: Yuan Hai , Silverman Richard B.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Alicyclic N‐Substituted 1,3‐Amino Alcohols via 1,3‐Oxazines.
Authors: Balazs Arpad , Szakonyi Zsolt , Fueloep Ferenc
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Nucleic Acid Related Compounds. Part 142. Trifluoromethylation of Alkenyl Bromides and Iodides (Including 5‐Iodouracils) with (CF3)2Hg and Cu (“Trifluoromethylcopper”).
Authors: Nowak Ireneusz , Robins Morris J.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Iterative Stereospecific Reagent‐Controlled Homologation of Pinacol Boronates by Enantioenriched α‐Chloroalkyllithium Reagents.
Authors: Blakemore Paul R. , Burge Matthew S.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Mesityltriphenylbismuthonium Tetrafluoroborate as an Efficient Bismuth(V) Oxidant: Remarkable Steric Effects on Reaction Rates and Chemoselectivities in Alcohol Oxidation.
Authors: Matano Yoshihiro , Suzuki Takeshi , Shinokura Tomonori , Imahori Hiroshi
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Facile One‐Pot Synthesis of Acyclic β‐Enamino Ketones, an Important Class of Versatile Synthetic Intermediates.
Authors: Choudhury Anusuya , Breslav Michael , Grimm Jeffrey S. , Xiao Tong , Xu Dawei , Sorgi Kirk L.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
One‐Pot Reactions of 2,4‐(Dioxobutylidene)phosphoranes. Efficient Synthesis of 4‐(2‐Hydroxybenzoyl)salicylic Acid Derivatives and Buta‐1,3‐diene‐1,4‐dicarboxylates.
Authors: Holtz Edith , Albrecht Uwe , Langer Peter
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Chemoselective Synthesis of Asymmetrical Carbonate from Alcohol and Dimethyl Carbonate Catalyzed by Ytterbium(III) Triflate.
Authors: Yu Chuanming , Zhou Baocheng , Su Weike , Xu Zhenyuan
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Benzylic Substitution of Gramines with Boronic Acids and Rhodium or Iridium Catalysts.
Authors: de la Herran Gabriela , Segura Amaya , Csaky Aurelio G.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Novel Palladium Catalyst for the Amination of Electron‐Rich Indole Derivatives.
Authors: Schwarz Nicolle , Tillack Annegret , Alex Karolin , Sayyed Iliyas Ali , Jackstell Ralf , Beller Matthias
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Reaction of Aziridines with Nitriles and Carbonyls: Synthesis of Imidazolines and Oxazolidines.
Authors: Gandhi Shikha , Bisai Alakesh , Prasad B. A. Bhanu , Singh Vinod K.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A New Series of Non‐Classical Type C Heteropentalenes: 2H‐Pyrrolo[2,1‐c][1,2,4]triazoles.
Authors: Moderhack Dietrich , Schneider Jan‐Christoph
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Chiral Diphenylprolinol TES Ether Promoted Conjugate Addition—Aldol‐Dehydration Reactions Between α,β‐Unsaturated Aldehydes and 2‐N‐Protected Amino Benzaldehydes.
Authors: Li Hao , Wang Jian , Xie Hexin , Zu Liansuo , Jiang Wei , Duesler Eileen N. , Wang Wei
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Enantioselective Synthesis of 2,3‐Disubstituted Piperidines.
Authors: Calosso Michael , Wagner Mathieu , Gendrineau Thomas , Petit Morgane , Kadouri‐Puchot Catherine , Dechoux Luc
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A New Synthesis Method for Benzo[f]quinolin‐3‐carbonyl Urea and Thiourea Derivatives in Aqueous Media Catalyzed by TEBAC.
Authors: Wang Xiang‐Shan , Zhang Mei‐Mei , Zeng Zhao‐Sen , Shi Da‐Qing , Tu Shu‐Jiang , Wei Xian‐Yong , Zong Zhi‐Min
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Regioselective Synthesis of Quinazoline Containing Novel Monoaryl Ethers at Room Temperature.
Authors: Deore Vijaykumar , Lohar Manoj V. , Yewalkar Nilambari , Mundada Ramswaroop , Ranaware Seema , Kumar Sanjay
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
N‐(4‐(4‐(2‐Halogenophenyl)piperazin‐1‐yl)butyl) Substituted Cinnamoyl Amide Derivatives as Dopamine D2 and D3 Receptor Ligands.
Authors: Saur Oliver , Hackling Anneke E. , Perachon Sylvie , Schwartz Jean‐Charles , Sokoloff Pierre , Stark Holger
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Synthesis of Azepine Derivatives via Copper‐Mediated Cyclization of 2‐Aza‐hepta‐2,4‐dien‐6‐ynyl Anions. Intramolecular Addition of Organocopper Centers to the C—C Triple Bond.
Authors: Lyaskovskyy Volodymyr , Bergander Klaus , Froehlich Roland , Wuerthwein Ernst‐Ulrich
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Pd‐Catalyzed Arylation/Ring‐Closing Metathesis Approach to Azabicycles.
Authors: Martinez‐Estibalez Unai , Sotomayor Nuria , Lete Esther
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Lithio Siloles: Facile Synthesis and Applications.
Authors: Wang Chao , Luo Qian , Sun Hui , Guo Xiangyu , Xi Zhenfeng
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Homogeneous Gold‐Catalyzed Hydrosilylation of Aldehydes.
Authors: Lantos Diana , Contel Maria , Sanz Sergio , Bodor Andrea , Horvath Istvan T.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Generation of Phosphorus‐Centered Radicals via Homolytic Substitution at Sulfur.
Authors: Carta Paola , Puljic Nicolas , Robert Carine , Dhimane Anne‐Lise , Fensterbank Louis , Lacote Emmanuel , Malacria Max
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Xylogranatin E, a New Phragmalin with a Rare Oxygen Bridge Between C1 and C29, from the Fruit of a Chinese Mangrove Xylocarpus granatum.
Authors: Wu Jun , Ding Haixin , Li Minyi , Zhang Si
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
An Aldol Approach to the Synthesis of the anti‐Tubercular Agent Erogorgiaene.
Authors: Yadav J. S. , Basak A. K. , Srihari P.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Convenient Microwave‐Assisted Synthesis of N‐Glycosyl Amino Acids.
Authors: Paolini Ilaria , Nuti Francesca , Pozo‐Carrero Maria de la Cruz , Barbetti Francesca , Kolesinska Beata , Kaminski Zbigniew J. , Chelli Mario , Papini Anna M.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Natural Products, Stylissadines A and B, Specific Antagonists of the P2X7 Receptor, an Important Inflammatory Target.
Authors: Buchanan Malcolm S. , Carroll Anthony R. , Addepalli Rama , Avery Vicky M. , Hooper John N. A. , Quinn Ronald J.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Total Synthesis of (+)‐Sundiversifolide.
Authors: Yokoe Hiromasa , Sasaki Hiroyuki , Yoshimura Tomoyuki , Shindo Mitsuru , Yoshida Masahiro , Shishido Kozo
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Total Synthesis of (‐)‐Hennoxazole A.
Authors: Smith Thomas E. , Kuo Wen‐Hsin , Bock Victoria D. , Roizen Jennifer L. , Balskus Emily P. , Theberge Ashleigh B.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Durinskiol A: A Long Carbon‐Chain Polyol Compound from the Symbiotic Dinoflagellate Durinskia sp.
Authors: Kita Masaki , Roy Michael C. , Siwu Eric R. O. , Noma Isao , Takiguchi Takahiro , Itoh Motoyuki , Yamada Kaoru , Koyama Tomoyuki , Iwashita Takeshi , Uemura Daisuke
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Laurentixanthone C: A New Antifungal and Algicidal Xanthone from Stem Bark of Vismia laurentii.
Authors: Tala Michel F. , Krohn Karsten , Hussain Hidayat , Kouam Simeon F. , Wabo Hippolyte K. , Tane Pierre , Schulz Barbara , Hu Qunxiu
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Aplyronine A, a Potent Antitumor Macrolide of Marine Origin, and the Congeners Aplyronines B and C: Isolation, Structures, and Bioactivities.
Authors: Ojika Makoto , Kigoshi Hideo , Yoshida Yoshifumi , Ishigaki Takeshi , Nisiwaki Masanori , Tsukada Itaru , Arakawa Masayuki , Ekimoto Hisao , Yamada Kiyoyuki
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Prospects for Metabotropic Glutamate 1 Receptor Antagonists in the Treatment of Neuropathic Pain.
Authors: Schkeryantz Jeffrey M. , Kingston Ann E. , Johnson Michael P.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ca2+ Channel α2‐δ Ligands for the Treatment of Neuropathic Pain.
Authors: Field Mark J. , Li Zheng , Schwarz Jacob B.
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Kv7 (KCNQ) Channel Modulators and Neuropathic Pain.
Authors: Munro Gordon , Dalby‐Brown William
Published: July 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.