bluuebunny/crossref_metadata_2025 huggingface dataset:
Selenium‐ and Tellurium‐Containing Multifunctional Redox Agents as Biochemical Redox Modulators with Selective Cytotoxicity
Authors: Jamier Vincent , Ba Lalla A. , Jacob Claus
Published: July 2010

Various human diseases, including different types of cancer, are associated with a disturbed intracellular redox balance and oxidative stress (OS). The past decade has witnessed the emergence of redox‐modulating compounds able to utilize such pre‐existing disturbances in the redox state of sick cells for therapeutic advantage. Selenium‐ and tellurium‐based agents turn the oxidizing redox environment present in certain cancer cells into a lethal cocktail of reactive species that push these cells over a critical redox threshold and ultimately kill them through apoptosis. This kind of toxicity is highly selective: normal, healthy cells remain largely unaffected, since changes to their naturally low levels of oxidizing species produce little effect. To further improve selectivity, multifunctional sensor/effector agents are now required that recognize the biochemical signature of OS in target cells. The synthesis of such compounds provides interesting challenges for chemistry in the future.
Electrochemical Deodorization and Disinfection of Hog Manure
Authors: Bejan Dorin , Rabson Lisa M. , Bunce Nigel J.
Published: July 2010

Electrolysis of liquid hog manure under direct current achieved amelioration of odour, in terms of both odour quality and odour intensity, and simultaneously reduced the population of odour‐causing bacteria by two orders of magnitude. A comparison of anode materials indicated that hydroxyl radical‐forming anodes (boron‐doped diamond and Ebonex) were the most effective, but unfortunately these materials are not yet available commercially in large size format. Dimensionally stable anodes composed of Ti/IrO2 were found to be satisfactory; lead‐based anodes leached unacceptable quantities of inorganic lead into the treated manure, and graphite anodes tended to disintegrate on long‐term use. The mechanism of action of the bactericidal effect involves a combination of toxicity by O2 that is released at the anode and hypochlorination due to the chloride ion that is present in manure. The proposed technology was shown to be successful at the 27 L scale in an on‐farm demonstration.
Cleaving the βO4 Bonds of Lignin Model Compounds in an Acidic Ionic Liquid, 1‐H‐3‐Methylimidazolium Chloride: An Optional Strategy for the Degradation of Lignin
Authors: Jia Songyan , Cox Blair J. , Guo Xinwen , Zhang Z. Conrad , Ekerdt John G.
Published: July 2010

The hydrolysis of βO4 bonds in two lignin model compounds was studied in an acidic ionic liquid, 1‐H‐3‐methylimidazolium chloride. The βO4 bonds of both guaiacylglycerol‐β‐guaiacyl ether and veratrylglycerol‐β‐guaiacyl ether underwent catalytic hydrolysis to produce guaiacol as the primary product with more than 70 % yield at 150 °C. Up to 32 wt % substrate concentration could be treated in the system without a decrease in guaiacol production. The ionic liquid could be reused without loss of activity in guaiacol production from both guaiacylglycerol‐β‐guaiacyl ether and veratrylglycerol‐β‐guaiacyl ether. A possible mechanism accounting for the guaiacol production is presented.
Inhibition of the alternative pathway of complement activation reduces inflammation in experimental autoimmune uveoretinitis
Authors: Chen Mei , Muckersie Elizabeth , Luo Chang , Forrester John V. , Xu Heping
Published: July 2010

We have shown previously that complement factor H (CFH) and complement factor B (CFB) are constitutively expressed by retinal pigment epithelial cells and their production is regulated by inflammatory cytokines, suggesting that the alternative pathway (AP) of complement activation might play a role in retinal inflammation. In this study, we further investigated the role of the AP in retinal inflammation using experimental autoimmune uveoretinitis (EAU) as a model. Mice with EAU show increased levels of C3d deposition and CFB expression in the retina. Retinal inflammation was suppressed clinically and histologically by blocking AP‐mediated complement activation with a complement receptor of the Ig superfamily fusion protein (CRIg‐Fc). In line with reduced inflammation, C3d deposition and CFB expression were markedly decreased by CRIg‐Fc treatment. Treatment with CRIg‐Fc also led to reduced T‐cell proliferation and IFN‐γ, TNF‐α, IL‐17, and IL‐6 cytokine production by T cells, and reduced nitric oxide production in BM‐derived macrophages. Our results suggest that AP‐mediated complement activation contributes significantly to retinal inflammation in EAU. CRIg‐Fc suppressed retinal inflammation in EAU by blocking AP‐mediated complement activation with probable direct effects on C3/C5 activation of macrophages, thus leading to reduced nitric oxide production by infiltrating CRIg− macrophages.
Ordered Olivine‐Type Lithium–Cobalt and Lithium–Nickel Phosphates Prepared by a New Precursor Method
Authors: Koleva Violeta , Zhecheva Ekaterina , Stoyanova Radostina
Published: July 2010

Single phases of olivine‐type LiCoPO4 and LiNiPO4 were synthesized by thermal treatment of homogeneous lithium–metal–phosphate–formate precursors obtained by freeze drying of aqueous solutions of the corresponding metal formates and LiH2PO4. The structure, thermal behavior, and morphology of the precursors were studied by IR spectroscopy, DTA, and SEM. Cobalt and nickel phosphate–formate precursors have a composition LiMHx(PO4)(HCOO)x·yH2O, where the formate and phosphate groups are mainly deprotonated. For the Co precursor the formate and phosphates ions are randomly coordinated to both Co and Li cations, whereas for the Ni precursor there is a preferential coordination of the formate and phosphate ions around the Ni2+ and Li+ ion, respectively. Thermal treatment of the precursors yields single phases of olivine‐type LiCoPO4 at 450 °C and LiNiPO4 at 700 °C. Structural analysis evidences that both LiCoPO4 and LiNiPO4 have an ordered olivine‐type structure without any Li to M disorder between the metal positions and lithium deficiency. The effect of the freeze‐dried solution concentration and annealing temperature on the structure, crystallite size, and morphology of LiCoPO4 and LiNiPO4 has been discussed. The morphology of the cobalt and nickel phospho‐olivines comprises isometric particles with mean sizes of 190 and 380 nm, respectively.
Effects of torsion on the behavior of peripheral steel‐braced frame systems
Authors: Erduran Emrah , Ryan Keri L.
Published: July 2010

In this study, the torsional response of buildings with peripheral steel‐braced frame lateral systems is evaluated. A three‐dimensional model of a three story braced frame with various levels of eccentricity is created and the effects of torsion on the seismic response is assessed for four hazard levels. The response history analysis results indicate that, unlike frame structures, the torsional amplifications in the inelastic systems exceed those of corresponding elastic systems and tend to increase with an increase in the level of inelasticity. The ability of two simplified procedures, elastic response spectrum analysis and pushover analysis, to capture the torsional amplifications in steel‐braced frames is evaluated. Copyright © 2010 John Wiley & Sons, Ltd.
Ethical dilemmas in treating clients with eating disorders: A review and application of an integrative ethical decision‐making model
Authors: Matusek Jill Anne , Wright Margaret O'Dougherty
Published: July 2010

Ethical dilemmas frequently arise in the treatment of clients with eating disorders, and clinicians regularly encounter an array of ethical challenges related to whether or not overt and covert coercive tactics should be implemented. In this paper, the authors provide an overview of perplexing ethical questions relevant to medical, nutritional and psychological treatment of clients with eating disorders including imposed treatment, enforced feeding, the duty to protect minors and adults, the determination of competence and capacity among medically comprised clients, and the effectiveness of coercive treatment for clients with eating disorders. The processes of ethical decision‐making in terms of ethical principles, professional codes of conduct, the existing empirical literature and the use of a decision‐making framework are explored. Taking a collaborative and client‐sensitive approach, the authors outline and apply an integrative ethical decision‐making model to facilitate clinicians' decision‐making process. Copyright © 2010 John Wiley & Sons, Ltd and Eating Disorders Association.
The interaction between cerebrovascular disease and neuroticism in late‐life depression: a cross‐sectional study
Authors: Wouts L. , Janzing J.G. , Lampe I.K. , Franke B. , de Vegt F. , Tendolkar I. , van Iersel M.B. , Buitelaar J.K. , Oude Voshaar R.C.
Published: July 2010

Objective

Vascular disease and neuroticism are both risk factors for late‐life depression. In this study we examined the interaction between vascular disease and neuroticism as determinants of clinically relevant depressive symptoms (CRDS) in late‐life.

Methods

Multivariate logistic regression in a survey of 1396 population‐dwelling people aged ≥70 years. CRDS were defined as scoring ≥16 on the CES‐D. Vascular disease was categorised into four levels: none, ≥2 vascular risk factors, cardiac disease or stroke.

Results

Neuroticism was strongly associated with CRDS in women (OR: 1.6, 95% CI: 1.4–1.8). In men vascular disease interacted negatively but significantly with neuroticism (cardiac disease by neuroticism: OR: 0.8, 95% CI: 0.6–0.9; stroke by neuroticism: OR: 0.8, 95% CI: 0.6–0.96) when predicting CRDS.

Conclusions

In men vascular disease attenuates the predictive value of neuroticism in CRDS, which might be mediated by apathy caused by cerebrovascular disease. Copyright © 2010 John Wiley & Sons, Ltd.
Relevance of a scoring system including CD11c expression in the identification of splenic diffuse red pulp small B‐cell lymphoma (SRPL)
Authors: Baseggio L. , Traverse‐Glehen A. , Callet‐Bauchu E. , Morel D. , Magaud J.P. , Berger F. , Salles G. , Felman P.
Published: July 2010

‘Splenic red pulp lymphoma with numerous basophilic villous lymphocytes’ (SRPL), recently described, is characterized by clinical, morphologic, immunologic, cytogenetic and molecular features distinct from SMZL/SLVL and HCL. In particular, the intensity of CD11c staining (expressed as fluorescence intensity ‐RFI‐) in SRPL is significantly different from the RFI in SMZL/SLVL and HCL. Moreover the use of a scoring system based on the expression of CD11c, CD22, CD76, CD38 and CD27 appears to improve the differential diagnosis between SRPL and SMZL/SLVL and emphasizes that SRPL is an entity closed to but distinct from SMZL/SLVL. Copyright © 2010 John Wiley & Sons, Ltd.
Modulators of cancer cell invasiveness
Authors: Kan Jean S. , DeLassus Gregory S. , D'Souza Kenneth G. , Hoang Stanley , Aurora Rajeev , Eliceiri George L.
Published: July 2010

Cell invasiveness is essential for cancer metastasis. Many proteins, and more recently also non‐coding RNAs, particularly microRNAs (miRNAs), have been reported to affect the cell invasiveness of various cancers. There is an apparent gap between the high number of these macromolecules and the low number of signaling pathways experimentally verified to control cancer invasiveness. We have brought together these various proteins and RNAs because we could not find any publication that filled this important gap. We have noted 589 proteins, 28 miRNAs, and 1 long non‐coding RNA that are reported to modulate invasiveness in cells of various cancers. Interestingly, 44 proteins enhance invasiveness in cells of some cancers, but suppress it in cells of others. Almost all of the proteins that show experimentally verified activation/inhibition effects on, or binding interactions with, each other are linked together in a single network, in a “hub‐and‐spoke” architecture. The accumulated data show trends that point to anticipated future results and highlight gaps in what is known about invasiveness signaling. Identification of cancer invasiveness signaling networks is important for combination and personalized targeted therapies of cancers. J. Cell. Biochem. 111: 791–796, 2010. © 2010 Wiley‐Liss, Inc.
Ring‐chain tautomerism in 2,2‐bis(2‐thienyl)tetrahydrofurans: preparation of [butene‐2H5]‐tiagabine
Authors: Herbert John M. , Mathers Trevor W.
Published: July 2010

A concise preparation of [butene‐2H5]‐tiagabine hydrochloride starting from [2H6]‐γ‐butyrolactone is described. It was necessary to ring‐open the labeled γ‐butyrolactone precursor before the addition of 2‐thienyllithium to avoid cyclisation of the intermediate to a 2,2‐bis(2‐thienyl)tetrahydrofuran. Copyright © 2010 John Wiley & Sons, Ltd.
A novel method for stereospecific fluorination at the 2′‐arabino‐position of pyrimidine nucleoside: synthesis of [18F]‐FMAU
Authors: Turkman Nashaat , Gelovani Juri G. , Alauddin Mian M.
Published: July 2010

Direct fluorination of a pyrimidine nucleoside at the 2′‐arabino‐position has been deemed to be extremely difficult, if not impossible. The conventional synthesis of 2′‐deoxy‐2′‐fluoro‐5‐methy‐1‐β‐D‐arabinofuranosyluracil (FMAU) and its 5‐substituted analogs involves stereospecific fluorination of the 1,3,5‐tri‐O‐benzoyl‐α‐D‐ribofuranose‐2‐sulfonate ester followed by bromination at the C1‐postion, and then coupling with pyrimidine‐bis‐trimethylsilyl ether. Several radiolabeled nucleoside analogs, including [18F]FMAU, and other 5‐substituted analogs, were developed according to this methodology. However, routine production of these compounds using this multi‐step process is inconvenient and limits their clinical application. We developed a novel precursor and method for direct fluorination of preformed nucleoside analogs at the 2′‐arabino position, exemplified via radiosynthesis of [18F]FMAU. The 2′‐methylsulfonyl‐3′,5′‐O‐tetrahydropyranyl‐N3‐Boc‐5‐methyl‐1‐β‐D‐ribofuranosiluracil was synthesized in multiple steps. Radiofluorination of this precursor with K18F/kryptofix produced 2′‐deoxy‐2′‐[18F]fluoro‐3′,5′‐O‐tetrahydropyranyl‐N3‐Boc‐5‐methyl‐1‐β‐D‐arabinofuranosiluracil. Acid hydrolysis followed by high‐performance liquid chromatography purification produced the desired [18F]FMAU. The average radiochemical yield was 2.0% (decay corrected, n=6), from the end of bombardment. Radiochemical purity was >99%, and specific activity was >1800 mCi/µmol. Synthesis time was 95–100 min from the end of bombardment. This direct fluorination is a novel method for synthesis of [18F]FMAU, and the method should be suitable for production of other 5‐substituted pyrimidine analogs, including [18F]FEAU, [18F]FIAU, [18F]FFAU, [18F]FCAU, and [18F]FBAU. Copyright © 2010 John Wiley & Sons, Ltd.
Significance of the resection of ovarian metastasis from colorectal cancers
Authors: Fujiwara Ayako , Noura Shingo , Ohue Masayuki , Shingai Tatsushi , Yamada Terumasa , Miyashiro Isao , Ohigashi Hiroaki , Yano Masahiko , Ishikawa Osamu , Kamiura Shoji , Tomita Yasuhiko
Published: July 2010

Background

The incidence of ovarian metastases from colorectal cancers (CRCs) has been reported to occur in 3–8% of CRC patients, and the prognosis for patients is very poor. We assessed the clinicopathological characteristics of CRC patients with ovarian metastasis and the significance of the resection of ovarian metastases.

Methods

We retrospectively analyzed 22 CRC patients with ovarian metastases. Synchronous ovarian metastases occurred in 8 patients and metachronous ovarian metastases occurred in 14 patients. Peritoneal dissemination was observed in nine patients.

Results

The mean follow‐up period was 45.3 months. The overall survival at 3 years following diagnosis of ovarian metastases is estimated to be 51.1% and 43.8% at 5 years. The overall survival at 5 years in the group of patients without peritoneal disseminations was 77.9%, which is significantly longer than that of the patients with disseminations (0%) (P = 0.0009). An R0 resection of metastatic sites was achieved in 15 patients and was associated with a significant increase in survival time (P = 0.0002).

Conclusions

Our study shows that aggressive resection of ovarian metastases from CRCs is associated with better overall survival. Peritoneal dissemination is an adverse prognostic factor, but R0 resection significantly improves the overall survival of these patients. J. Surg. Oncol. 2010;102:582–587. © 2010 Wiley‐Liss, Inc.
Herringbone‐grooved bearing with non‐uniform grooves for high‐speed spindle
Authors: Ikeda Shinichi , Arakawa Yo , Hishida Noriaki , Hirayama Tomoko , Matsuoka Takashi , Yabe Hiroshi
Published: July 2010

A hydrodynamic bearing with non‐uniform herringbone grooves has been developed for use with high‐speed motor spindles. The grooves gradually become narrower, shallower and less straight (curved) towards the herringbone centre along axial direction, resulting in an increased pumping effect of the spiral grooves. The optimum dimensions of the grooves for increasing the critical bearing number were clarified theoretically, and bearings with non‐uniform herringbone grooves were found to increase the critical bearing number against the half‐frequency whirl up to about 50% in comparison to bearings with uniform herringbone grooves. Experiments to investigate the suitability of the proposed bearing for high‐speed spindles showed that the maximum rotational speed of a spindle with this bearing was about 20% higher, close to the theoretically predicted 23%, and thus proved that application of this bearing should enable spindles to achieve faster stable rotation as theoretically expected. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of Mo content on electrochemical behaviour of TiMo alloys for dental applications
Authors: Mareci D. , Chelariu R. , Gordin D. M. , Romas M. , Sutiman D. , Gloriant T.
Published: July 2010

Corrosion behaviour of the new TiMo alloys together with the currently used metallic biomaterials commercial pure titanium (Cp‐Ti) was investigated for dental applications. Ingots of composition Ti12Mo, Ti20Mo and Ti40Mo were synthesized by the cold crucible levitation melting (CCLM) technique. All the samples were examined using electrochemical techniques: open circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in two electrochemical media: artificial saliva and in commercial mouthwash solution with 450 ppm F− (Astera©, EU), at 25 °C. The passive behaviour for all the Ti samples is observed for artificial saliva and for commercial mouthwash solution. The results suggest a non‐predominant fluoride effect on the passive behaviours of titanium samples. The EIS technique was applied to study the nature of the passive film formed on all the samples at various potentials in artificial saliva and in commercial mouthwash solution. Equivalent circuits (EC) were used to modelling EIS data, in order to characterize samples surface and better understanding the effect of Mo addition on the Cp‐Ti. The TiMo alloys, with a dendritic arrangement, appear to possess superior corrosion resistance than the Cp‐Ti in both electrochemical media.
Corrosion resistance of low‐nickel duplex stainless steel rebars
Authors: Bertolini L. , Gastaldi M.
Published: July 2010

The use of stainless steel bars in reinforced concrete structures may be an effective method to prevent corrosion in aggressive environments where high amounts of chlorides may penetrate in the concrete cover. For an estimation of the service life of structures where stainless steel bars are used, the chloride threshold for these rebars should be defined, and the influence of chemical composition and metallurgical factors that may affect the corrosion resistance (strengthening, welding, etc.) should be assessed. To reduce the cost of stainless steel reinforcement, duplex stainless steels with low nickel content have been recently proposed as an alternative to traditional austenitic steels, even though, few results are available regarding their corrosion performance in chloride contaminated concrete. This paper deals with the corrosion resistance of low‐nickel duplex stainless steel rebars (1.4362 and 1.4162) as a function of the chloride content. Comparison is made with traditional austenitic steels. An attempt to define a chloride threshold for the different stainless steels is made by comparing the results of several test procedures both in concrete and in solution.
Impedance spectroscopy: An efficient tool to determine the non‐steady‐state chloride diffusion coefficient in building materials
Authors: Sánchez I. , López M. P. , Ortega J. M. , Climent M. Á.
Published: July 2010

One of the most important problems of reinforced steel concrete in marine environments is the corrosion of the reinforcing bars. Most of the times, this corrosion is a consequence of the local destruction of the passive layer formed on the surface of the embedded steel, due to the arrival of chlorides present in the environment. Many efforts have been made to determine the chloride diffusion coefficient in concrete structures, both using natural diffusion methods, and accelerated migration methods. This coefficient determines the velocity of ingress of chlorides, and as a consequence the life time of the structures. In this work it is presented the possibility of using the technique of impedance spectroscopy, that is, very simple to use and requires no chemical or conductivity measurement, to determine the value of the non‐steady‐state diffusion coefficient. This technique, together with the equivalent circuits proposed for the interpretation of the measurements, allows the determination of the chloride saturation of a concrete or mortar sample. Pores of the material that are initially filled with water have high resistivity, and as the chlorides penetrate into the sample the value of the resistivity decreases. This diminution can be determined in situ, and permits the calculation of the diffusion coefficient saving experimental time and efforts. The results have been obtained both with concrete and mortar samples, and using different cement types.
Characterization of tissue structure at varying length scales using temporal diffusion spectroscopy
Authors: Gore John C. , Xu Junzhong , Colvin Daniel C. , Yankeelov Thomas E. , Parsons Edward C. , Does Mark D.
Published: July 2010

The concepts, theoretical behavior and experimental applications of temporal diffusion spectroscopy are reviewed and illustrated. Temporal diffusion spectra are obtained using oscillating‐gradient waveforms in diffusion‐weighted measurements, and represent the manner in which various spectral components of molecular velocity correlations vary in different geometrical structures that restrict or hinder free movements. Measurements made at different gradient frequencies reveal information on the scale of restrictions or hindrances to free diffusion, and the shape of a spectrum reveals the relative contributions of spatial restrictions at different distance scales. Such spectra differ from other so‐called diffusion spectra which depict spatial frequencies and are defined at a fixed diffusion time. Experimentally, oscillating gradients at moderate frequency are more feasible for exploring restrictions at very short distances which, in tissues, correspond to structures smaller than cells. We describe the underlying concepts of temporal diffusion spectra and provide analytical expressions for the behavior of the diffusion coefficient as a function of gradient frequency in simple geometries with different dimensions. Diffusion in more complex model media that mimic tissues has been simulated using numerical methods. Experimental measurements of diffusion spectra have been obtained in suspensions of particles and cells, as well asin vivoin intact animals. An observation of particular interest is the increased contrast and heterogeneity observed in tumors using oscillating gradients at moderate frequency compared with conventional pulse gradient methods, and the potential for detecting changes in tumors early in their response to treatment. Computer simulations suggest that diffusion spectral measurements may be sensitive to intracellular structures, such as nuclear size, and that changes in tissue diffusion properties may be measured before there are changes in cell density. Copyright © 2010 John Wiley & Sons, Ltd.
B0 inhomogeneity‐insensitive triple‐quantum‐filtered sodium imaging using a 12‐step phase‐cycling scheme
Authors: Fleysher Lazar , Oesingmann Niels , Inglese Matilde
Published: July 2010

Triple‐quantum‐filtered (TQF) sodium MRI can be used to separate sodium NMR signals from different physiological compartments. Although three‐pulse triple‐quantum filtering has been demonstrated to be better suited for in vivo imaging, the absence of the refocusing pulse in the filter increases its sensitivity to magnetic field inhomogeneities. Therefore, several TQF cycles have been developed previously to correct image distortions caused by B0 inhomogeneities. In this paper, we present a new 12‐step phase‐cycling TQF scheme based on three radiofrequency pulses which allows the compensation of B0 variations both with and without ancillary B0 map information. The method offers 40% higher signal‐to‐noise‐ratio efficiency compared with the previously developed B0‐correcting phase‐cycling schemes. Copyright © 2010 John Wiley & Sons, Ltd.
Water effect on the rheologic behavior of PAN solution during thermal‐induced gelation process
Authors: Tan Lianjiang , Pan Ding , Pan Ning
Published: July 2010

The thermal‐induced gelation process in a polyacrylonitrile (PAN) solution containing different amounts of water was investigated through both dynamic and steady‐state rheologic measurements. During the cooling process, the storage modulus G′ was found to intersect with the loss modulus G″ at a temperature which can be considered as the incipient gel point Tig. This crossover point increased with the water content in the PAN solution. On the basis of the power law $G'\tilde{G}\tilde{\omega} {}^{n} $ and the relation ${\rm tan}\ \delta = G(\omega )/G^{'}(\omega ) = {\rm tan}(n\pi /2) = {\rm const}$, the loss tangent tan δ was traced with decreased temperature at various oscillation frequencies, and a crossover point was observed at the temperature a little higher than the Tig above for all PAN solutions. The water content might affect the value of the relaxation exponent n via two different mechanisms, that is, hydration decoupling of the pendant nitrile groups in PAN at low water content (2 wt% water) and molecule aggregation at high water content (4 and 6 wt%). Nevertheless, the slight difference in the n values reflects the unique structure of the critical gels irrespective of the water level. The apparent viscosity ηa of either the PAN solution or the PAN gel was found to rise with increased water content and both showed pronounced shear‐thinning behavior. Compared with temperature, the water effect on the apparent viscosity ηa is more significant due to the water‐induced aggregation of the molecular chains. Copyright © 2010 John Wiley & Sons, Ltd.
Chain extension of adipic acid and (or) succinic acid/butanediol polyesters with 2,2′‐(1,4‐phenylene)‐bis(2‐oxazoline) and adipoylbiscaprolactamate combined chain extenders
Authors: Xu Shao Yi , Shi Yan Hong , Zhao Jing Bo , Jiang Sheng Ling , Yang Wan Tai
Published: July 2010

This paper provided an easy and flexible method to synthesize high molecular weight polyesters by polycondensation and chain extension. Low molecular weight polybutylene adipate, polybutylene succinate, and poly(butylene succinate‐co‐butylene adipate) (PBSA) were synthesized through melt condensation polymerization from adipic acid and/or succinic acid with butanediol. The prepolyesters obtained had different amount of COOH and OH terminal groups. Chain extension of them was carried out at 180–240°C using 2,2′‐(1,4‐phenylene)‐bis(2‐oxazoline) and adipoyl biscaprolactamate as combined chain extenders. The influencing factors of the chain extension were studied. At the optimal conditions, chain‐extended polybutylene adipate with Mn up to 39,100, polybutylene succinate with intrinsic viscosity of 0.99 dl/g, and PBSA with intrinsic viscosity from 0.73 to 0.81 dl/g were synthesized. The chain‐extended polyesters were characterized by IR spectrum, 1H NMR spectrum, differential scanning calorimetry, thermogravimetric analysis (TGA), wide angle X‐ray scattering, and tensile test. The thermal analysis showed that chain extension often led to slight decrease of the regularity, the crystallinity, and the melting point. This deterioration of the properties is not harmful enough to impair their thermal properties and obstruct them from being used as biodegradable thermoplastics. The TGA showed that the chain‐extended polyesters were stable with initial decomposition temperature over 354.7°C. The tensile strength of the chain extended PBS and PBSAs with butylene adipate units less than 20 mol% was in the range of 18.95–31.22 MPa. Copyright © 2010 John Wiley & Sons, Ltd.
The impact of resorcinol bis(diphenyl phosphate) and poly(phenylene ether) on flame retardancy of PC/PBT blends
Authors: Liu Shumei , Jiang Lei , Jiang Zhijie , Zhao Jianqing , Fu Yi
Published: July 2010

Flame retardancy of bisphenol A polycarbonate (PC)/poly(butylene terephthalate) (PBT) blends was improved by the addition of resorcinol bis(diphenyl phosphate) (RDP) and poly(phenylene ether) (PPO). A PC/PBT blend at 70/30 weight ratio obtained a V‐0 rating by the addition of 10 wt% RDP and 10 wt% PPO. The combination of 5 wt% methyl methacrylate‐butadiene‐styrene tercopolymer (MBS) with 3 wt% ethylene‐butylacrylate‐glycidyl methacrylate tercopolymer (PTW) causes a remarkable increase in toughness of the PC/PBT/RDP blend while maintaining a high rigidity. A detailed investigation of the flame‐retardant action of PC/PBT/RDP and PC/PBT/RDP/PPO blends was performed using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), TGA‐FTIR, temperature‐programmed pyrolysis/gas chromatography/mass spectrometry (TPPy/GC/MS), and scanning electron microscopy/energy dispersive spectrometer (SEM/EDS). The results demonstrate that RDP induces a higher char yield at ca. 450 °C and synchronously increases the thermal stability of the blend with PPO. The flame‐retardant role of RDP in the condensed phase was discerned from TGA, FTIR, and SEM/EDS of the residues. Copyright © 2010 John Wiley & Sons, Ltd.
Phase separation of polyphosphazene/poly(lactide‐co‐glycolide) blends prepared under different conditions
Authors: Cai Qing , Wang Ying , Yang Fei , Shen Hong , Yang Xiaoping , Wang Shenguo
Published: July 2010

Using a mutual solvent technique, blend films of poly[(alaine ethyl ester)0.62(glycine ethyl ester)0.38]phosphazene/poly(lactide‐co‐glycolide) (PAGP/PLGA blend) were prepared at different conditions including weight ratios, solvents, environmental humidity, film thickness, and substrates. The morphology and properties of blend films were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDX), X‐ray photoelectron spectrometry (XPS), and solvent selective etching. Compared with dichloromethane and tetrahydrofuran (THF), chloroform was the better solvent to form miscible PAGP/PLGA blend films at relatively anhydrous atmosphere. However, in the humid atmosphere, the hexagonal arrangement of holes appeared on the surface of PAGP/PLGA blend films due to the ordered array of water droplets. A sandwich‐liked structure was formed with the hydrophilic PAGP component at the top and bottom, while the PLGA component in the middle. In addition, the surface morphology of PAGP/PLGA blend films was also influenced by the film thickness and the property of the substrate. Copyright © 2010 John Wiley & Sons, Ltd.
Tailoring spectral position and width of field enhancement by focused ion‐beam patterning of plasmonic nanoparticles
Authors: Rosa Lorenzo , Sun Kai , Szymanska Joanna , Hudson Fay E. , Dzurak Andrew , Linden Andre , Bauerdick Sven , Peto Lloyd , Juodkazis Saulius
Published: July 2010

We propose to use ion‐beam patterning of plasmonic nanoparticles made by standard electron beam lithography, plasmonic metal deposition, and lift‐off sequence. With this approach new three‐dimensional (3D) tailoring of nanoparticles becomes possible: cut through the particle and into the substrate, cut‐through at an angle, trim or bore nanoparticles or substrate. Here, we numerically simulate the expected optical properties of such 3D patterned nanoparticles. We show a particular case when spectrally broad extinction band can be created with a strong light field enhancement on a Si substrate.

magnified image

Nanoparticles with a 10–20 nm nano‐gap cut by ion‐beam at the chosen location and to the required depth into the substrate. Scanning electron microscopy (SEM) image of the fabricated Au‐nanoparticles.

(© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rheological properties of cereal starch gels and Mesona Blumes gum mixtures
Authors: Feng Tao , Gu Zhengbiao , Jin Zhengyu , Zhuang Haining
Published: July 2010

The effect of Mesona Blumes gum (MBG) was examined on steady and dynamic shear of MBG/rice starch and MBG/wheat starch gels. In addition, stress relaxation and creep tests were performed for two types of cereal starch gels. The flow curves of both MBG/starch gels exhibited pseudoplastic behavior at shear rates between 0.01 and 10 s−1, and the data were fitted into the power law model (R2 = 0.91–0.98). Dynamic mechanical spectrum showed that all gels were strong gels in frequency between 0.1 and 10 Hz. Stress relaxation data at different strains indicated a strain‐softening phenomenon for both gels. Data were fitted into Maxwell model (R2 = 0.91–0.98). Creep curves were conducted at the shear stress 6.4 Pa within linear viscoelastic region of both MBG/starch gels. Data were fitted into Burgers model (R2 = 0.91–0.98). Apparent viscosity η, storage moduli G′, equilibrium stress relaxation modulus Ge and zero apparent viscosity η0 of MBG/rice starch gels decreased in the following order: 6/0>6/0.5>6/0.35>6/0.1 (starch/gum w/w). Whereas η, G′, Ge, and η0 of MBG/wheat starch gels increased gradually along side the increase of MBG contents. The stress relaxation time λ of MBG/rice starch gels increased in the following order: 6/0<6/0.5<6/0.35<6/0.1 (starch/gum w/w) while λ of MBG/wheat starch gels decreased gradually with the increase of MBG level. The influence of MBG on two examined cereal starch is totally opposite.
Manufacturing Authenticity: The Cultural Production of National Identities in Singapore
Authors: CHONG TERENCE
Published: July 2010

According to Prasenjit Duara, the sacredness of the nation hinges on its ‘regimes of authenticity’ where timelessness and the politics of embodiment are key to an authentic national identity. This paper looks at three different cultural impulses that have attempted to manufacture authenticity in Singapore. They are: the Malay literary movementAngkatan Sasterawan 50prior to independence; the state-sponsored Confucian ethics discourse during the 1980s; and the romanticization of the working-class ‘heartlander’ through contemporary popular culture in confrontation with the politics of global capitalism and globalization. In doing so, this paper articulates the difference between the regimes of authenticity of state elites and non-state cultural producers, as well as their ‘national imaginaries’. It concludes that the regime of authenticity, that operationalizes the representations of the working class as a diametric opposite to the logic and force of globalization, offers the most popular symbols of national identity in Singapore.
Evaluating the adequacy of reserves in the Tembe–Tshanini Complex: a case study in Maputaland, South Africa
Authors: Gaugris J. Y. , Van Rooyen M. W.
Published: July 2010

The aim of this study was to determine the minimum conservation area needed to conserve vegetation types and their landscape and to apply it to an area in KwaZulu-Natal, South Africa, which is within the Maputaland Centre of Plant Endemism and part of the Maputaland–Pondoland–Albany biodiversity hotspot. Outside conservation areas this Centre of Plant Endemism is under threat from human utilization. We used a method initially designed to determine minimum conservation areas for rare plant species, which we adapted from its original country and context, to determine minimum conservation areas for landscape species in Maputaland’s little-documented environment. The minimum area required for conservation was established for the Sand Forest and Woodland vegetation types in the region. We found that sufficient habitat is presently conserved to preserve the Sand Forest but not the Woodlands. The method holds promise to provide answers to critical conservation issues in lesser-known environments and, although relatively difficult to establish for the first time, is an efficient and easy to use tool that can be refined once more knowledge becomes available.
Protected areas and community incentives in savannah ecosystems: a case study of Tanzania’s Maasai Steppe
Authors: Sachedina Hassan , Nelson Fred
Published: July 2010

Two issues of central importance to conservation are developing an improved understanding of the relative roles of state protected areas and local institutions and developing effective strategies for creating community-based incentives for conservation. We provide a case study of northern Tanzania’s Maasai Steppe to explore these issues in the context of a savannah ecosystem where wildlife is mobile and depends extensively on community lands for seasonal habitats. We compare the impacts and outcomes of four approaches to developing local incentives for wildlife conservation on community lands: protected area benefit-sharing, trophy hunting donations, village–private tourism concession contracts, and a direct payment scheme for habitat conservation. Tourism and direct payment concession areas have resulted in large areas of community land being protected for wildlife by villages as a result of the conditional and contractual nature of these ventures. By contrast, other approaches that provide economic benefits to communities but are not conditional on defined conservation actions at the local level demonstrate little impact on wildlife conservation on community lands. In spatially extensive ecosystems where protected areas cover limited areas and wildlife relies heavily on community and private lands, strategies based on maximizing the direct income of communities from wildlife are fundamental to the sustainability of such systems.
Status of the Endangered Egyptian vulture Neophron percnopterus in the Cantabrian Mountains, Spain, and assessment of threats
Authors: Mateo-Tomás Patricia , Olea Pedro P. , Fombellida Isidoro
Published: July 2010

The Egyptian vulture Neophron percnopterus is categorized as Endangered on the IUCN Red List, as well as on the European and Spanish Red Lists. Spain is home to the most important breeding population of Egyptian vultures in Europe but this population has differing trends at a regional scale. We present data for the Egyptian vulture population in the Cantabrian Mountains, north-west Spain, during the last 3 decades and assess the main threats to the species there. The Egyptian vulture population in the Cantabrian Mountains was estimated to be 175 breeding pairs in 2008, which comprised 13–14% of the Spanish population. This population has been stable, or increasing slightly, since 2000. During 2000–2008 4.3% of the Cantabrian Egyptian vulture population was affected by the use of illegal poison. During the same period the number of sheep and goats reared (which contributes to the maintenance of Egyptian vulture territories) was reduced by 27.4%, which could lead to food shortages for the vultures in the near future. Currently 32 breeding pairs (18.3% of the population) have wind turbines within their foraging areas, with an average of 59 wind turbines per territory (range 1–176). During the next few years this number will increase to 110 turbines per territory within 69 vulture territories (39.4% of the population). Nearly a third (32.6%) of breeding territories are located outside protected areas. Better coordination between administrative areas is needed to guarantee the conservation of the Cantabrian Mountains population of Egyptian vultures through effective surveillance and protection in the numerous existing protected areas.
The TARANIS laser: A multi-Terawatt system for laser-plasma investigations
Authors: Dzelzainis T. , Nersisyan G. , Riley D. , Romagnani L. , Ahmed H. , Bigongiari A. , Borghesi M. , Doria D. , Dromey B. , Makita M. , White S. , Kar S. , Marlow D. , Ramakrishna B. , Sarri G. , Zaka-Ul-Islam M. , Zepf M. , Lewis C.L.S.
Published: July 2010

The multi-Terawatt laser system, terawatt apparatus for relativistic and nonlinear interdisciplinary science, has been recently installed in the Centre for Plasma Physics at the Queen's University of Belfast. The system will support a wide ranging science program, which will include laser-driven particle acceleration, X-ray lasers, and high energy density physics experiments. Here we present an overview of the laser system as well as the results of preliminary investigations on ion acceleration and X-ray lasers, mainly carried out as performance tests for the new apparatus. We also discuss some possible experiments that exploit the flexibility of the system in delivering pump-probe capability.
Reduced abundance of late-successional trees but not of seedlings in heavily compared with lightly logged sites of three East African tropical forests
Authors: Kirika Jasper Mbae , Böhning-Gaese Katrin , Dumbo Bonny , Farwig Nina
Published: July 2010

Logged forests form an increasingly large proportion of tropical landscapes but disproportionately few studies have studied the impact of forest disturbance, e.g. lightly vs. heavily logged, on tree and seedling communities simultaneously. We sampled all trees (on 1 ha) and all recently germinated seedlings (on 90 m2) in three lightly and three heavily logged sites in each of the following three East African tropical forests: Budongo Forest and Mabira Forest in Uganda and Kakamega Forest in Kenya. We analysed species richness, diversity, abundance and community composition of late- and early-successional trees and seedlings. We recorded no difference in species richness or diversity of late-successional or early-successional trees between lightly and heavily logged sites. However, the abundance of late-successional species was lower in heavily than lightly logged sites. Moreover, there was no difference in species richness or diversity of trees among the three forests. Yet, abundances of late-successional trees were higher in Budongo Forest than in Mabira Forest and Kakamega Forest. Species richness, diversity and abundance of seedlings did not differ between lightly and heavily logged sites. Only the abundance of seedlings of late-successional species differed among the forests with more individuals in Budongo Forest than in Mabira Forest. This was corroborated by non-metric multidimensional scaling (NMDS) showing clear differences in composition of tree and seedling communities among the three forests. Thus, both, the tree and seedling communities differed significantly among the three forests but not between lightly and heavily logged sites.
Amphibian community structure as a function of forest type in Amazonian Peru
Authors: von May Rudolf , Jacobs Jennifer M. , Santa-Cruz Roy , Valdivia Jorge , Huamán Jusmell M. , Donnelly Maureen A.
Published: July 2010

The potential effect of forest type on the structuring of animal communities in western Amazonia remains poorly understood. In this study, we tested the hypothesis that amphibian species richness, composition and abundance differ across forest types in the lowland rain forest of south-eastern Peru. By using 320 individual transects, we compared the amphibian assemblages across four major forest types (floodplain, terra firme, bamboo and palm swamp) at each of four sites separated by 3.5–105 km. We identified 1967 individuals of 65 species in 11 families and found that a large proportion of the amphibian diversity in this region is attributed to habitat-related beta diversity. Overall, we found that forest type is more important than site in predicting both species composition and abundance. We also found that, when analyses are conducted separately for each forest type and include species abundance data, similarity between assemblages decreases with increasing geographic distance. In contrast to studies that considered species presence/absence but ignored species abundances, our results highlight the importance of including abundance data in the assessment of animal diversity patterns in western Amazonia. We conclude that evaluating community structure across forest types can improve our understanding of diversity patterns in this region.
Structure of local communities of endemic dung beetles in Madagascar
Authors: Viljanen Heidi , Wirta Helena , Montreuil Olivier , Rahagalala Pierre , Johnson Steig , Hanski Ilkka
Published: July 2010

The wet tropical forests in Madagascar have endemic dung beetles that have radiated for tens of millions of years using a limited range of resources produced by the species-poor mammalian fauna. Beetles were trapped in two wet-forest localities over 4 years (6407 trap nights, 18,869 individuals). More limited data for six other local communities were used to check the generality of the results. Local communities are relatively species poor (around 30 species) in comparison with wet-forest-inhabiting dung beetle communities elsewhere in the tropics (typically 50 or more species). The species belong to only two tribes, Canthonini and Helictopleurina (Oniticellini), which have evolved, exceptionally for dung beetle tribes, completely nocturnal versus diurnal diel activities, respectively. Patterns in the elevational occurrence, body size and resource use suggest that interspecific competition restricts the numbers of locally coexisting species exploiting the limited range of resources that are available. On the other hand, regional turnover in the species composition is exceptionally high due to a large number of species with small geographical ranges, yielding a very large total fauna of dung beetles in Madagascar (>250 species). Apart from exceptionally low local (alpha) diversity and high beta diversity, the Malagasy dung beetle communities are ecologically distinctive from comparable communities in other tropical regions in having high numerical dominance of the most abundant species, small average body size and low degree of resource specialization.
The Model that Never Moved: The Case of a Virtual Memory Theater and Its Christian Philosophical Argument, 1700–1732
Authors: Whitmer Kelly J.
Published: July 2010

Argument

By the year 1720, one could visit at least three large-scale wooden models of Solomon's Temple in the cities of Amsterdam, Hamburg, and Halle. For short periods of time, the Amsterdam and Hamburg Temple models were exhibited in London, where they attracted a great deal of attention. The Halle model, on the other hand, never moved from its original location: a complex of schools known today as the Francke Foundations (die Franckesche Stiftungen). This article explores the reasons for the Halle model's striking immobility by considering its position at the center of a long-distance network, also referred to as the Danish-Halle mission. In this article I argue that the Halle Temple model functioned as an effigy and memory theater that helped proponents of this mission make a case for the Temple's status as the world's first information technology. Young people moved around the wooden model; they took virtual pilgrimages with it and internalized its infrastructure by memorizing its various components. The model's position at the center of the complex's striking ethnographical collection and curricula exposes relations between the Danish-Halle mission, Christian philosophy, and an irenical turn as public policy in early eighteenth-century Brandenburg-Prussia.