bluuebunny/crossref_metadata_2025 huggingface dataset:
La politique forestière française, du rapport Bianco à la loi de juillet 2001 | Forestry politics in France: from the Bianco report to the law of July 2001
Authors: Buttoud Gérard
Published: June 2007

As in a number of other European countries, forestry policies in France have recently been adapted to meet new guidelines put into place by international debate on the durable management of forests, a debate which not only changed public perceptions but also the principles and mode of public decision-making. From the production of the Bianco Report up to the final vote on the adoption of the law on 9th July 2001, this reform took about 5 years. The mode of financing the forestry sector changed completely after the demise of the national forestry fund. The monitoring and evaluation of durable forest management has passed to the state under the outlines of PEFC (Pan European Forest Certification). At the same time,other structural reorganisations are underway in both public and private forests. Despite a high measure of semantic grooming, the new legislative and institutional framework in France reaffirms – to the detriment of a global solution to the demands of recreation and environmental – the fundamental importance of national wood production industries.
Die zukünftige Waldforschung an der WSL | The future of forest research at WSL
Authors: Broggi Mario F. , Oester Bernhard
Published: June 2007

Forest research is going through a period of decisive change in terms of both structure and values as a result of economic and social developments. Researchers from the Department «Forest» at WSL have, therefore, been discussing potential challenges with other experts in order to be able to identify problems early and anticipate the consequences of global developments. We have been asking ourselves questions like: Are we doing the right thing? And are we doing it in the right way?

We have drawn on these discussions in setting our longterm goals and core research areas for the next few years. The Department «Forest» plans to continue to focus mainly on ecological research but also to consider topics more from the points of view of economics and direct implementation. Steps in this direction have already been taken. The WSL Programme«Future-oriented Management of Forest Use» has been launched and the Section «Economics» has been strengthened with more people employed. The Section «Silvicultural Strategies» focuses on studying long-term forest development. It then uses these research findings to work out effective silvicultural strategies to steer the development of the forest.

Thorough knowledge of the forest ecosystem and of the processes that take place within it is essential in order to answer the many questions raised. The Section «Forest Ecosystems and Ecological Risks» is investigating these processes and cause-effect relationships in forest ecosystems. It estimates the risks arising from changing environmental conditions. The Section«Soil Ecology» is concerned with long-term processes and changes taking place in the soil. It studies the influence of the increased deposition of acids, nitrogen compounds and inorganic pollutants, in particular heavy metals, on the soil and the associated risks to plants, soil-dwelling creatures and the groundwater.

The Section «Forest and Environmental Protection» has become known as the centre for expertise on forest health in Switzerland. It makes recommendations and disseminates research findings and data to do with current issues in forest conservation.

We are performing top research in these areas and are well known in international research circles, as the ETH-Council expects us to be. We intend in future to offer more support to those responsible for or interested in forests by providing applicable and future-oriented solutions to important and complex problems.
La cipollatura nel legno di castagno: un problema centrale per il rilancio della castanicoltura da legno di qualità | Ring shake in chestnut: a main problem for the resumption of quality chestnut wood cultivation
Authors: Fonti Patrick , Giudici Fulvio , Conedera Marco
Published: June 2007

Ring shake poses one of the biggest problems for the management of chestnut coppices. New studies show that, within the framework of high-quality silviculture, it is possible to lessen the risk of ring shake. In this contribution we summarise important results from investigations carried out by the Sottostazione Sud delle Alpi of the WSL. In addition,possible measures resulting from the investigations are described to prevent and contain the risk of ring shake.
Ursachen und Verlauf der Buchdrucker-Epidemien (Ips typographus L.) in der Schweiz von 1984 bis 1999 | Causes and progress of the eight-toothed spruce bark beetle epidemics (Ips typographus) in Switzerland from 1984 to 1999
Authors: Meier Franz , Gall Rolf , Forster Beat
Published: June 2007

In the past 20 years, several mass attacks by the eight-toothed spruce bark beetle (Ips typographus L.) occurred in Switzerland. Since 1984 data on compulsory fellings, numbers of infestation spots and numbers of beetles captured in pheromone traps have been collected in all Swiss forest districts. The annual data were published in short reports.

This paper gives an overview of the progress of bark beetle epidemics from 1984 to 1999. On the national level, two periods with epidemics of the spruce bark beetle can be distinguished. The first epidemic started after windthrows and drought in the years 1982 and 1983. It reached its height in 1984/1985 and faded at the end of the decade. The second epidemic started after the storm Vivian (February 1990). It reached its height in 1992/1993 and ended in 1997. Storm damage that produced high quantities of suitable breeding material was not the only factor for the bark beetle gradation;weather conditions were also exceptional, such as hot and dry vegetation periods.

Windthrows and exceptional weather conditions are mostly events on regional scales and do not affect the whole country with the same intensity. The gradation that appears to be an «epidemic of the spruce bark beetle in Switzerland after the storm Vivian» is in truth the accumulation of several local epidemics. This is shown by the number of compulsory fellings and infestation spots analysed at regional levels. Extreme weather conditions and storms not only directly influence the bark beetle population, they also stress standing trees, thus creating suitable breeding material for bark beetles. To analyse the influence of exceptional weather conditions on bark beetle epidemics,it is therefore necessary to evaluate regional data.
Le pinson du Nord Fringilla montifringilla L.: un visiteur d'exception dans les forêts d'Ajoie durant l'hiver 2001–2002 | The brambling Fringilla montifringilla L.: a rare visitor in the forests of Ajoie in winter 2001/2002
Authors: Chalverat Joseph
Published: June 2007

In the winter of 2001/2002, over a period lasting 110 days, ten to twelve million bramblings (northern Eurasian finches)sought a place to sleep in the region of Villars-sur-Fontenais in Canton Jura, Switzerland. Suitable resting places in the proximity of access roads enabled a great number of ornithologists to carry out regular and numerous observations that were collected by the author in Jura's Natural Science Museum in Porrentruy. A lot of new information on the behaviour of the bramblings at their places of rest was collected, both during the day, on their return, and was also closely observed and described with regard to weather conditions and the change of season. Information was also collected on the ethology of predators.

The special aspect of the article is the visit to the resting places after the departure of the bramblings. Much new knowledge was gained from this. Pseudombrophila stercofringilla,a newly discovered Ascomyzete, was actually found by its discoverer in situ. The effect was detected of uric acid,which turned the ground plants brown and destroyed fir needles from the previous year. It would be a worthwhile subject of scientific inquiry to study the effect of enrichment with fertiliser – manifest on trees and mushrooms. A regional study would make it possible to examine whether the scratching activity of the bramblings, allowing beechnuts to fall on fruitful ground, have a positive effect of regeneration of beech forests in the long term.
Modelling of mechanical properties of wood and wood-based materials
Authors: Gustafsson Per Johan
Published: June 2007

Modelling is a wide concept. This paper describes various meanings of modelling in relation to mechanical properties of wood and wood-based materials. Three examples of modelling by means of the finite element method, presented in recent years in PhD theses, are used as reference points. They relate to modelling of the micro-structure of wood and its mechanical properties, modelling of drying-induced distortion of boards and modelling of the micro-structure and properties of dry-shaped cellulose fibre materials. The paper concludes with remarks on some studies relating to fracture simulations,strength modelling and glued joints.
Field Emission SEM Studies on Softwood Tracheids and Hardwood Fibres – A Review of Activities at the EMPA Wood Laboratory
Authors: Zimmermann Tanja , Sell Jürgen
Published: June 2007

Over the past ten years transverse fracture surfaces of tensionloaded softwoods, hardwoods and reaction wood have been studied using a high resolution FE SEM. Due to the fracture process the cell wall becomes loosened and its components can be distinctly observed (as opposed to smooth cross sections of cut wood). Softwood tracheids (compression wood, too) and hardwood fibres showed predominantly radial orientations(perpendicular to the other layers) of the cellulosic fibrils of the secondary wall layer 2 (S2). Similar structures were found on sections of different hardwoods degraded by white rot fungi. Contrary to that finding there is no discernible preferential orientation of the cellulose fibrils in the S2 or G layer of pronounced tension wood cells.

In our opinion functional advantages of such structures in the strengthening tissue are quite clear. The sandwich-like structure is important for the buckling resistance of the tracheids and fibre cell walls and therefore also to the bending stiffness of the whole tree. Tension wood fibres of hardwood trees solely exposed to longitudinal tension do probably not need a compression stiffening, explaining why transverse fibril agglomerations are absent here. In many other studies a polylaminated concentric arrangement of the cellulose/ ligninhemicellulose matrix in the S2 layer is postulated and clearly documented.

Taking our results into account, we conclude that concentric and/or radial arrangements (perpendicular to the CML) in the S2 of softwood tracheids and hardwood fibres coexist for good ontogenetic, physiological, and mechanical reasons.
Qualitative and Quantitative Analysis of Plastics, Polymers and Rubbers by Vibrational Spectroscopy
Authors: Chalmers John M. , Everall Neil J.
Published: June 2007

The vibrational spectroscopy techniques of infrared spectroscopy and Raman spectroscopy are widely used for the analysis and characterization of organic polymers, plastics and rubbers, and their products. They are used to both identify and to probe the molecular microstructure and morphology of polymers and articles fabricated from them, and to investigate and monitor their synthesis and manufacture.

This chapter begins with a short discussion on the range of sample forms and properties that are amenable to study using vibrational spectroscopy. This is followed by concise descriptions of sampling techniques as they apply to polymer analysis. Discussions of qualitative and quantitative analysis and the peculiarities associated with polymer infrared and Raman spectra are then followed by more specific applications sections, which cover: dichroism and molecular orientation; end groups and branching; hydrogen bonding; blends and miscibility studies; copolymer composition; polymerisation and cure studies; degradation and oxidation; chromatography, pyrolysis, evolved gas analysis and thermogravimetric analysis coupled with vibrational spectroscopy; optical properties and constants; two‐dimensional vibrational spectroscopy; process measurements; and, infrared and Raman microspectroscopy.

This chapter is a prelude to the more specific and specialized chapters that follow in this book.
Vibrational Spectroscopic Analysis for the Determination of
S
tructure–
A
ctivity
R
elationships (
SARs
) in Molecular Binding
Authors: Pivonka Don E. , Noda Isao
Published: June 2007

This chapter details an application of vibrational spectroscopy that has been developed as a tool for understanding how both the physical structure and the electronic properties of a molecule are related to activity within a biological assay, i.e., the structure‐activity relationship (SAR). In that context, vibrational spectroscopy has first been developed as a tool for identification of the molecular subcomponents within a compound series that play an active role in binding kinetics. Second, vibrational spectroscopy has exhibited utility in uncovering electronic trends within both pendant functional groups and within the molecular backbone scaffold that foster the binding process.

In this chapter, several series of compounds, within a human estrogen receptor (β‐ER) study, are used to illustrate the feasibility of the technique. In each series, infrared and Raman band shifts that correlated with β‐ER activity, were identified. Also in each series, the electronic state of the fused ring scaffold system was found to play a critical role in binding. The ability to relate the physical/electronic state of a molecular subcomponent to activity has far reaching implications in the identification and optimization of binding activity. The preliminary success of this project opens the door to a much broader investigation of the technique using a host of spectroscopic methodologies.
Fabrication of Au/PVP nanofiber composites by electrospinning
Authors: Wang Yongzhi , Li Yaoxian , Sun Guoen , Zhang Guangliang , Liu Hui , Du Jianshi , Yang Songtao , Bai Jie , Yang Qingbiao
Published: June 2007

Gold nanoparticles prepared by trisodium citrate reduction of HAuCl4 in poly(vinylpyrrolidone) (PVP) ethanol solution were dispersed into PVP nanofibers by electrospinning. The optical property of Au nanoparticles before and after electrospinning was measured by UV‐Vis. The morphology and distribution of gold nanoparticles in PVP nanofibers were observed by transmission electron microscopy (TEM). The influence of the amount of Au added to and the concentration of PVP in electrospinning solution over the morphology of Au/PVP nanofibers were studied. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Some factors influencing exfoliation and physical property enhancement in nanoclay epoxy resins based on diglycidyl ethers of bisphenol A and F
Authors: Ingram S. , Rhoney I. , Liggat J. J. , Hudson N. E. , Pethrick R. A.
Published: June 2007

An investigation of the factors influencing the degree of exfoliation of an organically modified clay in a series of epoxy resins is reported. The use of sonication, choice of curing agent, effect of the moisture content of the clay, and the cure temperature were examined. The dispersion was characterized using a combination of rheological measurements, X‐ray diffraction, and dynamic mechanical thermal analysis. Rheological analysis of the clay dispersion in the epoxy monomer indicated that at high clay loads Herschel–Bulkley type behavior is followed. Higher cure temperatures and higher levels of clay moisture were found to influence the extent of exfoliation. Improvements in physical properties were observed through the addition of nanocomposites. The DGEBA/DDM and DEGEBA/DDS exhibited 2 and 4°C increase, respectively, in Tg per wt % of added clay. DGEBF showed virtually no enhancement. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007
Effect of end group content on photochromic behavior of spiropyran in polycaprolactone–poly(ethylene succinate) blends
Authors: Samoladas A. , Jannakoudakis A. , Bikiaris D. , Chrissafis K. , Paraskevopoulos K. M.
Published: June 2007

The photochromic behavior of the spiropyran 1′,3′‐dihydro‐8‐methoxy‐1′,3′,3′‐trimethyl‐6‐nitrospiro[2H‐1‐benzopyran‐2,2′‐(2H)‐indole] has been investigated in thin films of polycaprolactone–poly(ethylene succinate) blends containing different weight ratios of poly(ethylene succinate) (PESu) and spiropyran. The effects of molecular weight and end group content (COOH and OH) of PESu into the coloration–decoloration rate of the fabricated photochromic films have also been examined. The films were exposed to UV radiation (365 nm) at ambient temperature and the absorbance spectra of each polymer blend film were recorded for different time periods. The increase of the amount of PESu in the polymer substrate from 20 to 40 wt % shifts the absorbance towards shorter wavelengths. The same trend was also observed with the increase of carboxyl and hydroxyl groups of the macromolecular chain of the added PESu. Interactions between the polar polymer groups and the spiropyran species, which are formed under the UV excitation, seem to contribute to the color stabilization of the photochromic films. The photochromic response revealed unexceptional repeatability between the slightly colored spiropyran and the intense colored amphoteric species for all the examined polymer matrices. The decoloration rate of the spiropyran–polymer blends follow the kinetic of a first order reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Polymerization of acrylonitrile using potassium peroxydisulfate as an initiator in the presence of a multisite phase‐transfer catalyst: A kinetic study
Authors: Vajjiravel Murugesan , Umapathy M. J. , Bharathbabu M.
Published: June 2007

In this article, the kinetics and mechanism of the free‐radical polymerization of acrylonitrile (AN) using potassium peroxydisulfate (PDS) as a water‐soluble initiator in the presence of synthesized 1,4‐bis(triethyl methyl ammonium) benzene dichloride (DC‐X) as a phase‐transfer catalyst (PTC) were studied. The polymerization reactions were carried out under inert and unstirred conditions at a constant temperature of 60 ± 1°C in cyclohexane/water biphasic media. The rate of polymerization (Rp) increased with an increase in the concentrations of AN, PTC, and PDS. The order with respect to the monomer, initiator, and PTC was found to be 1.0, 0.5, and 0.5, respectively. Rp was independent of the ionic strength and pH of the medium. However, an increase in the polarity of the solvent slightly increased the Rp value. On the basis of the obtained results, a mechanism is proposed for the polymerization reaction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Pervaporation characteristics and structure of poly(vinyl alcohol)/poly(ethylene glycol)/tetraethoxysilane hybrid membranes
Authors: Ye Li Yi , Liu Qing Lin , Zhang Qiu Gen , Zhu Ai Mei , Zhou Guo Bo
Published: June 2007

Poly(vinyl alcohol) (PVA) blended with poly(ethylene glycol) (PEG) was crosslinked with tetraethoxysilane (TEOS) to prepare organic–inorganic PVA/PEG/TEOS hybrid membranes. The membranes were then used for the dehydration of ethanol by pervaporation (PV). The physicochemical structure of the hybrid membranes was studied with Fourier transform infrared spectra (FT‐IR), wide‐angle X‐ray diffraction WXRD, and scanning electron microscopy (SEM). PVA and PEG were crosslinked with TEOS, and the crosslinking density increased with increases in the TEOS content, annealing temperature, and time. The water permselectivity of the hybrid membranes increased with increasing annealing temperature or time; however, the permeation fluxes decreased at the same time. SEM pictures showed that phase separation took place in the hybrid membranes when the TEOS content was greater than 15 wt %. The water permselectivity increased with the addition of TEOS and reached the maximum at 10 wt % TEOS. The water permselectivity decreased, whereas the permeation flux increased, with an increase in the feed water content or feed temperature. The hybrid membrane that was annealed at 130°C for 12 h exhibited high permselectivity with a separation factor of 300 and a permeation flux of 0.046 kg m−2 h−1 in PV of 15 wt % water in ethanol. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Novel high‐dielectric‐permittivity poly(vinylidene fluoride)/polypropylene blend composites: The influence of the poly(vinylidene fluoride) concentration and compatibilizer
Authors: Dang Zhi‐Min , Yan Wei‐Tao , Xu Hai‐Ping
Published: June 2007

Novel high‐dielectric‐permittivity poly(vinylidene fluoride) (PVDF)/polypropylene (PP) blend composites were prepared via a blending technology, and their dielectric properties were studied over wide ranges of temperatures and frequencies. To improve the interface bonding between PVDF and PP, a suitable compatibilizer, polypropylene‐graft‐maleic anhydride (PP‐g‐MAH), was employed. The results showed that the concentration of PVDF in the composites dominated the changes in the dielectric properties and that the use of PP‐g‐MAH could improve the interface interaction between PVDF and PP, resulting in an increase in the dielectric permittivity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
pH‐sensitive swelling and release behaviors of anionic hydrogels for intelligent drug delivery system
Authors: Kim Bumsang , Shin Youngchan
Published: June 2007

The pH‐sensitive swelling and release behaviors of the anionic P(MAA‐co‐EGMA) hydrogels were investigated as a biological on–off switch for the design of an intelligent drug delivery system triggered by external pH changes. There was a drastic change of the equilibrium weight swelling ratio of P(MAA‐co‐EGMA) hydrogels at a pH of around 5, which is the pKa of poly (methacrylic acid) (PMAA). At a pH below 5, the hydrogels were in a relatively collapsed state but at a pH higher than 5, the hydrogels swelled to a high degree. When the molecular weight of the pendent poly(ethylene glycol) (PEG) of the P(MAA‐co‐EGMA) increased, the swelling ratio decreased at a pH higher than 5. The pKa values of the P(MAA‐co‐EGMA) hydrogels moved to a higher pH range as the pendent PEG molecular weight increased. When the feed concentration of the crosslinker of the hydrogel increased the swelling ratio of the P(MAA‐co‐EGMA) hydrogels decreased at a pH higher than 5. In release experiments using Rhodamine B (Rh‐B) as a model solute, the P(MAA‐co‐EGMA) hydrogels showed a pH‐sensitive release behavior. At low pH (pH 4.0) a small amount of Rh‐B was released while at high pH (pH 6.0) a relatively large amount of Rh‐B was released from the hydrogels. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Preparation and characterization of TiO2 and polymer nanocomposite films with high refractive index
Authors: Nakayama Norio , Hayashi Toyoharu
Published: June 2007

Novel nanocomposite films of TiO2 nanoparticles and hydrophobic polymers having polar groups, poly (bisphenol‐A and epichlorohydrin) or copolymer of styrene and maleic anhydride, with high refractive indices, high transparency, no color, solvent‐resistance, good thermal stability, and mechanical properties were prepared by incorporating surface‐modified TiO2 nanoparticles into polymer matrices. In the process of preparing colloidal solution of TiO2 nanoparticles, severe aggregation of particles can be reduced by surface modification using carboxylic acids and long‐chain alkyl amines. These TiO2 nanoparticles dispersed in solvents were found not to aggregate after mixing with polymer solutions. Transparent colorless free‐standing films were obtained by drying a mixture of TiO2 nanoparticles colloidal solution and polymer solutions in vacuum. Transmission electronic microscopic studies of the films suggest that the TiO2 nanoparticles of 3–6 nm in diameter were dispersed in polymer matrices while maintaining their original size. Thermogravimetric analysis results indicate that the nanocomposite film has good thermal stability and the weight fraction of observed TiO2 nanoparticles in the film is in good accordance with that of theoretical calculations. The refractive index of nanocomposite films of TiO2 and poly(bisphenol‐A and epichlorohydrin) was in the range of 1.58–1.81 at 589 nm, which linearly increased with the content of TiO2 nanoparticles from 0 to 80 wt %. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effect of blending high‐pressure low‐density polyethylene on the crystallization kinetics of linear low‐density polyethylene
Authors: Kathy Liu Jiameng , Nozue Yoshinobu , Nagamatsu Tatsuhiro , Hosoda Satoru
Published: June 2007

It is well known that the addition of a small amount of high‐pressure low‐density polyethylene (HP‐LDPE) to linear low‐density polyethylene (LLDPE) can improve the optical properties of LLDPE, and LLDPE/HP‐LDPE blend is widely applied to various uses in the field of film. The optical haziness of polyethylene blown films, as a result of surface irregularities, is thought to be as a consequence of the different crystallization mechanisms. However, not much effort has been directed toward understanding the effect of HP‐LDPE blending on the overall crystallization kinetics (k) of LLDPE including nucleation rate (n) and crystal lateral growth rate (v). In this study, we investigated the effect of blending 20% HP‐LDPE on the crystallization kinetics of LLDPE polymerized by Ziegler‐Natta catalyst with comonomer of 1‐butene. Furthermore, by combining depolarized light intensity measurement (DLIM) and small‐angle laser light scattering (SALLS), we have established a methodology to estimate the lateral growth rate at lower crystallization temperatures, in which direct measurement of lateral growth by polarized optical microscopy (POM) is impossible due to the formation of extremely small spherulites. This investigation revealed that HP‐LDPE blending leads to enhanced nucleation rate, reduced crystal lateral growth rate, and a slight increase in the overall crystallization kinetics of pure LLDPE. From the estimated crystal lateral growth rate, it was found that the suppression in v from HP‐LDPE blending is larger at lower temperatures than at higher temperatures. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Degradation behavior of polyoxymethylene: Influence of different stabilizer packages
Authors: Archodoulaki V.‐M. , Lüftl S. , Seidler S.
Published: June 2007

Stabilizer effects of two types (homopolymer and copolymer) of commercially available polyoxymethylenes containing two different stabilizer packages under various aging conditions have been studied by the application of thermogravimetric analysis coupled with mass spectrometry. Increasing yellowness during thermooxidative aging has been observed. Investigations of the melt volume rate have proved that the UV‐stabilized materials exhibit a higher increase in the melt volume rate after oven aging, which is caused by reactions of the additives, than the solely heat‐stabilized materials. The thermogravimetric analysis/mass spectrometry investigations have proved broad synergy effects between the heat‐ and UV‐stabilizer systems. The formation of chains with thermally stable end groups or of cyclic products proceeds during aging, particularly in the presence of UV stabilizers. This formation might be the result of intermolecular transacetalization reactions. The degradation behavior of UV‐irradiated homopolymer and copolymer samples has also been investigated. Oven storage and weathering cause comparable shifts in the derivative thermogravimetry traces, so similar damage reactions can be suggested. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis and properties of hydrogen‐bonded poly(amide‐imide) hybrid films
Authors: Tsai Mei‐Hui , Huang Shih‐Liang , Lin J. C. Muti , Ko Cheng‐Jung , Chen Ying‐Ling , Lu Chun‐Mei , Chen Chiou‐Juy , Yen Chia‐Hui
Published: June 2007

Poly(amide‐imide), PI, hybrid films are prepared by using sol–gel techniques. First, the poly(amide amic acid) with controlled block chain length of 5000 and 10,000 g/mol and uncontrolled chain length are synthesized by condensation reaction with 4,4′‐diaminodiphenyl ether (ODA), 3,3′,4,4′‐benzophenonetetracarboxylic dianhydride (BTDA), trimellitic anhydride chloride (TMAC) and terminated with p‐aminopropyltrimethoxysilane (APrTMOS). And then the imidization reactions of poly (amide amic acid) are proceeded to obtain the poly (amide‐imide) hybrid film. Hybrid films with 5000 g/mol block chain length possess higher storage modulus, lower glass transition temperature and damping intensity comparing to films with 10,000 g/mol block chain length. The addition of TMAC to the poly(amide‐imide) hybrids is due to the increase of toughness and intermolecular hydrogen bonding, which is the average strength of intermolecular bonding and studied by the hydrogen‐bonded fraction (fbonded), frequency difference (Δν) and shiftment. Meanwhile, PI hybrid films containing more APrTMOS and TMAC content possess higher thermal and mechanical properties. On the other hand, hybrid films with 10,000 g/mol block chain length and more TMAC content have higher gas permeabilities than other films. The degradation temperatures of 5 wt % loss of all hybrid films are all higher than 540°C and increased as the increase of TMAC content. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis and Antibacterial Activity of tert‐Butyl [1‐benzyl‐2[(4‐aryl‐2‐thiazolyl)hydrazono]ethyl]carbamate Derivatives
Authors: Turan‐Zitouni Gülhan , Fehrentz Jean‐Alain , Chevallet Pierre , Martinez Jean , Kaplancıklı Zafer Asim , Özdemir Ahmet , Arslanyolu Muhittin , Yıldız Mehmet Taha
Published: June 2007

The increasing clinical importance of drug‐resistant fungal and bacterial pathogens has lent additional urgency to microbiological research and new antibacterial compound development. For this purpose, new tert‐butyl[1‐benzyl‐2[(4‐aryl‐2‐thiazolyl)hydrazono]ethyl]carbamate derivatives were synthesized and evaluated for antibacterial activity. The reaction of Boc‐L‐phenylalaninal with thiosemicarbazide gave the thiosemicarbazone which furnished the title compounds by reaction with phenacyl bromides. The newly synthesized compounds were screened for antibacterial activity and toxicity. While microdilution broth susceptibility assay was used for the antibacterial activity evaluation of the compounds against the strains E. coli (NRRL B‐3704), M. luteus (NRRL B‐4375), B. cereus (NRRL B‐3711), P. aeruginosa (NRRL B‐23), and S. fecalis (NRRL B‐14617), the Artemia salina 96‐well assay was used to determine cytotoxicities of the compounds. Observations obtained from the bioassays showed that some of the compounds are highly active against E. coli, M. luteus, and B. cereus when compared with the control agent and showed low toxicity.
Synthesis and Antidepressant‐Like Profile of Novel 1‐Aryl‐3‐[(4‐benzyl)piperidine‐1‐yl]propane Derivatives
Authors: Köksal Meriç , Bilge S. Sırrı
Published: June 2007

This study describes the chemical synthesis and pharmacological evaluation of some new 1‐aryl‐3‐[(4‐benzyl)piperidine‐1‐yl]propane derivatives as antidepressants. The structures attributed to the compounds were elucidated using IR and 1H‐NMR spectroscopic techniques besides elemental analysis. The antidepressant‐like effect of these compounds was assessed by using the forced swimming test (FST), a validated experimental model of depression in mice. A clear antidepressant‐like effect was shown for compounds 1, 2 and 4 by a significant decrease in immobility behaviour.
Guardianship determinations by judges, attorneys, and guardians
Authors: Gavisk Melanie , Greene Edith
Published: June 2007

Guardianship is intended to protect incapacitated individuals through the appointment of a surrogate decision maker. Little is known about how judges, attorneys, and professional guardians assess the need for guardianship, to what extent they apply statutory guidelines when making these determinations, and how their decisions compare. Three groups of participants (probate judges, elder law attorneys, and professional guardians) read vignettes portraying older adults that varied in the extent to which the evidence supported the appointment of a guardian. They were asked about the appropriateness of various resolutions. Participants were reluctant to endorse full guardianship even when warranted by the evidence and preferred informal, family‐based interventions that do not involve legal action. Professional groups did not always agree on the appropriate resolutions, suggesting that one's professional orientation may play a role in perceptions of older adults. Copyright © 2007 John Wiley & Sons, Ltd.
Reactions of Ytterbocenes with Diimines: Steric Manipulation of Reductive Reactivity
Authors: Trifonov Alexander A.
Published: June 2007

This review is devoted to the investigation of reactions of ytterbocenes with diimines. These reactions are found to be strongly influenced by the steric crowding in the coordination sphere of the metal atom and the coordination capacities of π‐aromatic ligands coordinated to the ytterbium. The reactions may occur with oxidation of the ytterbium atom as well as with retention of its oxidation state. C–C bond formation, C–H bond activation, C=N bond insertion, and oxidative Yb–C bond cleavage processes are documented for reactions of ytterbocenes with diimines. Steric overcrowding of the coordination sphere of the ytterbium atom can induce “extra” reducing ability of ytterbocenes and allow them to act not only as one‐ but also as two‐electron reductants with respect to diimines. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Effects of moisture content, impulse polarity and earth electrode's dimension on dry and wet sand under high voltage conditions
Authors: Nor N. Mohamad , Ramli A.
Published: June 2007

The study on the physics of discharges in soil and performance of earthing networks subjected to lightning currents are important in order to improve the reliability of electrical systems and to obtain better electrical models of earthing systems. The soil characteristics of various moisture contents under high‐impulse currents have been well studied in previous studies. In this present study, fast impulse generator is used to investigate the dry soil characteristics in two cylindrical test cells of different outer radii; 15 and 20 cm under high magnitude fast impulse conditions of both impulse polarities. This allows to study the characteristics of dry soil under high‐impulse current conditions, and allows a comparison between the dry and wet soil characteristics under high‐impulse conditions such as before and after breakdown of the test cell. In this study, the effects of impulse polarities, moisture content in soil and the outer dimensions of test cell on the soil characteristics under high‐impulse currents were investigated. Copyright © 2007 John Wiley & Sons, Ltd.
Statistical characterization of impact of system variables on temporal dynamics of groundwater in highly weathered regoliths
Authors: Rasiah V. , Armour J. D. , Cogle A. L.
Published: June 2007

In situations where the water table fluctuates during the rainy season the characterization of the impact of system variables on the temporal dynamics of the groundwater (GW) is essential to improve the understanding at catchment or regional scale behaviour of GW. In this study the appropriateness of the statistical parameters; mean, median, the 80th percentile (PC80), coefficient of variation (CV), correlation coefficient (r), and multiple regression models were assessed to characterize the impact of system variables on the temporal dynamics of hydraulic head relative to ground surface (HH) during rainy seasons. The study was conducted from 1999 to 2003 in the wet tropical Johnstone River catchment (JRC) in north‐east Queensland, Australia. Piezometer wells were installed at 32 sites under cropping to 5–90 m depth on different soil types, landscape positions, and varying proximity to surface water bodies (i.e. four system variables). The HH was measured, at least at 10–15 day intervals during 1–5 consecutive rainy seasons. The HH in the 32 wells fluctuated throughout each of the five rainy seasons. The mean HH averaged over the seasons ranged from 1·1 to 17·2 m across the wells, the median from 0·9 to 17·3 m, and the PC80 from 0·3 to 16·1 m. The temporal behaviour of HH characterization by mean of means of HH, the mean of medians of HH, and the mean of PC80 of HH, indicated the HH can be classified to belong to three different groups for each one of these parameters. The impact of the system variables on temporal dynamics, explored using multiple regression procedure, indicated that the model for median was marginally better than mean. The CV was found to be most appropriate parameter to characterize the impact of GW system variable (aquifer type), a component of the system variables, on temporal dynamics. The interactions of GW (i) belonging to different GW system and (ii) at shoulder with footslope in a landscape were best characterized by simple linear correlations. Copyright © 2007 John Wiley & Sons, Ltd.
Stochastic simulation of droughts. Part 2: regional droughts
Authors: Mohan S. , Sahoo P. K.
Published: June 2007

In Part 1 we demonstrated the applicability of stochastic models to predicting the characteristics of point drought events within any planning period by means of a case study (Mohan S, Sahoo PK (2007) Hydrological Processes 21: this issue). In addition, studies on regional droughts are important in the context of regional level planning and evolving management strategies. The small number of drought events from a particular streamflow or rainfall series, when subjected to statistical analysis in order to predict future occurrences, produces results that are not very reliable. To overcome this difficulty, we propose using a long sequence of synthetically generated annual rainfall series at various rain‐gauge stations of a region, and multiyear regional droughts were derived from both historic and generated series. The key parameters for a successful regional multiyear drought study are the critical area ratio and the critical level, and the area affected by the drought can be ascertained using these parameters. The important regional drought parameters were determined and their suitable probability distributions were arrived at by studying a total of nine possible probability models; these models can be used in predicting the longest regional drought duration and the greatest regional drought severity with a given return period. The effect of change of critical parameters on the regional drought parameters is also studied and reported. Copyright © 2007 John Wiley & Sons, Ltd.
Stochastic simulation of droughts. Part 1: point droughts
Authors: Mohan S. , Sahoo P. K.
Published: June 2007

The number of drought events derived from the historic streamflow or rainfall series will be limited and produce results that are not very reliable. This study proposes a drought simulation methodology that uses a long sequence of synthetically generated monthly streamflow/rainfall series, from which it is possible to drive a large sample of drought events and the prediction of drought characteristics will be reliable. The modified Herbst method has been used to identify droughts in the generated streamflow and rainfall series. The drought simulation procedure is illustrated with a case study of the Bhadra reservoir catchment in Karnataka State, India. Monthly droughts were derived from both historic and generated monthly streamflow and rainfall series. The important drought characteristics were determined and the suitable probability distribution for each parameter was arrived at after studying seven different probability models. The use of the probability curves thus derived has been illustrated with examples (referred to in Part 1 as ‘point droughts’). Similarly, the development and application of stochastic models for the prediction of regional drought parameters have been illustrated with examples in the accompanying paper (Part 2: regional droughts). Copyright © 2007 John Wiley & Sons, Ltd.
Expression of osteopontin, a target gene of de‐regulated Wnt signaling, predicts survival in colon cancer
Authors: Rohde Franziska , Rimkus Caroline , Friederichs Jan , Rosenberg Robert , Marthen Carmen , Doll Dietrich , Holzmann Bernhard , Siewert Jörg‐Rüdiger , Janssen Klaus‐Peter
Published: June 2007

Osteopontin (OPN) is a secreted phosphoprotein, which has been reported to be associated with tumor progression in numerous solid tumors. In a previous transcriptome study on colorectal cancer, we identified the gene OPN among the most strongly up‐regulated transcripts. OPN has been suggested as a putative target of Wnt signaling, but the molecular mechanism responsible for its aberrant transcription is not fully understood. We analyzed 13 normal colon tissues, 9 adenomas, 120 primary colon tumors, and 10 liver metastases by quantitative reverse‐transcription PCR. OPN expression was strongly elevated in primary colon cancer and liver metastasis, but not in pre‐cancerous lesions and UICC stage I tumors. Multivariate analysis established OPN expression as an independent prognostic parameter for overall survival. Moreover, high OPN expression identified a subgroup of patients with bad prognosis. Next, we determined immunohistochemically a correlation of OPN expression with aberrant β‐catenin staining, which is indicative of Wnt activation. Elevated expression of OPN was significantly correlated with increased cytoplasmic and nuclear β‐catenin staining. The in vivo role of Wnt signaling for the expression of OPN was tested in genetically defined mouse models with (Apc1638N) or without (pvillin‐KRASV12G) Wnt activating mutations. Mutation of the tumor suppressor APC was necessary for upregulation of OPN expression in the murine tumors on transcript and on protein levels. Thus, OPN is a transcriptional target of aberrant Wnt signaling, and OPN expression alone predicts survival in human colon cancer. © 2007 Wiley‐Liss, Inc.
Paradoxical enhancement of CD8 T cell‐dependent anti‐tumor protection despite reduced CD8 T cell responses with addition of a TLR9 agonist to a tumor vaccine
Authors: Karan Dev , Krieg Arthur M. , Lubaroff David M.
Published: June 2007

Generation of antigen‐specific CD8+ T cell responses is considered optimal for an effective immunotherapy against cancer. In this study, we provide a proof of principle that in vitro observed diminished CD8+ T cell response provided a strong in vivo tumor protection. Immunization with an adenovirus vaccine containing ovalbumin (OVA) gene (Ad5‐OVA) strongly induces antigen‐specific CD8+ T cell responses measured in vitro using various immunological assays. However, in an attempt to augment the antigenic CD8+ T cell response, coinjection of a TLR9 agonist CpG ODN with the viral vaccine unexpectedly reduced the CD8+ T cell responses measured in vitro but provided a remarkably enhanced tumor protection compared to the CD8+ T cell response generated by Ad5‐OVA vaccine alone. Interestingly, despite reduced ex vivo/in vitro CD8+ T cell responses following Ad5‐OVA+CpG immunization, immunodepletion studies revealed that the augmented anti‐tumor immunity was primarily dependent on CD8+ T cells. The magnitude and effector function of anti‐OVA CD8+ T cells remain low following primary and secondary antigenic challenge, presenting a dichotomy between in vitro CD8 T cell responses and in vivo anti‐tumor immunity. To examine the impact of CpG ODN, we observed that presence of CpG suppresses the CD8+ T cell proliferation both in vitro and in vivo. These data demonstrate that coadministration of adenovirus vaccine with a TLR9 agonist can generate potentially effective tumor‐reactive CD8+ T cells in vivo. In addition, the results indicate that widely used standard immune parameters may not predict the vaccine efficacy containing a TLR9 agonist as adjuvant. © 2007 Wiley‐Liss, Inc.
Villous adenoma of extrahepatic bile duct: Contrast‐enhanced sonography findings
Authors: Xu Hui‐Xiong , Chen Li‐Da
Published: June 2007

We report a case of villous adenoma in the extrahepatic bile duct that was successfully diagnosed with contrast‐enhanced sonography (CEUS) before surgical resection. On baseline sonography, the mass appeared as a homogeneously isoechoic mass filling the bile duct from the confluence of the right and left hepatic ducts to the distal common bile duct. No intralesional flow signal was found on color Doppler imaging and power Doppler imaging. On CEUS, the mass showed homogeneous enhancement during arterial phase, thus confirming the neoplastic nature of the lesion. The enhancement decreased gradually so that the mass became hypoenhanced during portal and late phases. Surgical resection was performed, and pathologic examination confirmed a villous adenoma of the bile duct epithelium with mild dysplasia. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Tree‐ring reconstructions of precipitation and streamflow for north‐western Turkey
Authors: Akkemik Ünal , D'Arrigo Rosanne , Cherubini Paolo , Köse Nesibe , Jacoby Gordon C.
Published: June 2007

We describe tree‐ring reconstructions of spring (May‐June) precipitation and spring‐summer (May‐August) streamflow for north‐western Turkey, both beginning in AD 1650. These are among the first such reconstructions for the region, and the streamflow reconstruction is among the first of its kind for Turkey and the entire Middle East. The reconstructions, which both emphasize high‐frequency variations, account for 34 and 53% of their respective instrumental variance. Comparison to precipitation and runoff data provides some means of verification for the instrumental streamflow record, which is very short (30 years). Drought and flood events in the reconstructions are compared to historical archives and other tree‐ring reconstructions for Turkey. The results reveal common climatic extremes over much of the country. Many of these events have had profound impacts on the peoples of Turkey over the past several centuries. Copyright © 2007 Royal Meteorological Society
The internal variability of the RegCM3 over South Africa
Authors: Kgatuke M. M. , Landman W. A. , Beraki A. , Mbedzi M. P.
Published: June 2007

The aim of this study is to investigate the internal rainfall variability of a nested model system and of a regional climate model (RCM). Four solutions obtained through perturbing the wind fields at initialization for the ECHAM4.5 atmospheric general circulation model (AGCM) are used to force the RegCM3 RCM over South Africa. To determine the amount of variability introduced by non‐linearities in an RCM, four additional RegCM3 simulations are made through initializing the RegCM3 on different days but using a single realization from the ECHAM4.5. The simulations are made for one dry and one wet, El Niño‐Southern Oscillation (ENSO) associated summer season defined as December to February. The rainfall variability associated with non‐linearities in the nested system is high to an extent that ensemble members produce anomalies that have opposite signs in the same season. However, the sign of the ensemble average anomaly generally corresponds with the observed anomaly. The internal rainfall variability of the RCM is small when seasonal totals are analysed while with the daily rainfall totals the variability is larger. The number of events that fall into the three rainfall categories (i.e. below‐normal, normal and above‐normal) for the RegCM3 ensemble members are close to one another however the timing of the events is different. The results suggest that in seasonal operational forecasting making ensemble members associated with the internal variability of an RCM is not necessary because the information obtained from the ensemble members is almost similar. Copyright © 2007 Royal Meteorological Society