bluuebunny/crossref_metadata_2025 huggingface dataset:
Geochemistry and mineralogy of zeolitic tuffs from the Alaçatı (Çeşme) area, Turkey
Authors: Kaçmaz Hülya , Köktürk Uğur
Published: November 2004

Silicic vitric tuffs of the Alaçatı (Çeşme) area, west of Izmir (Turkey), are partly altered to authigenic zeolites and clay minerals. Mordenite and clinoptilolite-heulandite accompanied by smectite are the main alteration products of the tuffs. Scanning electron microscope examination indicates that mordenite forms mainly from a gel-like precursor and to a lesser degree from volcanic glass. Mordenite and clinoptilolite-heulandite have formed by the hydrolysis and dissolution of silicic vitric tuffs by thermal waters which circulated through the fracture zone into porous vitric tuffs. These thermal waters, which resulted from mixing of thermal (Na-Cl type) and groundwaters, provided the extra Na and Ca that are necessary for the formation of mordenite. Various percentages of calcite are present in the altered tuffs. The enrichment of calcite in the altered tuffs indicates that thermal waters supply Ca, sourced from dissolution of Triassic carbonate rocks.

The alteration minerals in the Alaçatı (Çeşme) area do not seem to be laterally zoned. The occurrence of the zeolites seems to be related to inferred fracture zones trending NE—SW. These fracture zones are important because they provide porosity and permeability in the tuffs for zeolite formation. The large glass content and permeability of tuffs accompanied by the favorable hydrochemical condition resulted in zeolitization of the Alaçatı (Çeşme) area.
The Nature of Co in Synthetic Co-substituted Goethites
Authors: Pozas Raúl , Rojas T. Cristina , Ocaña Manuel , Serna Carlos J.
Published: November 2004

The crystallochemical features of Co in Co-substituted goethite solid-solutions prepared by two different procedures have been studied using infrared, X-ray photoelectron and electron energy loss spectroscopies. It was found that the path followed for the synthesis of Co-substituted goethite determines the oxidation state of Co in the goethite structure. Thus, in the solid-solution prepared by precipitation with Na2CO3 of an Fe(II) aqueous solution containing Co(II) cations, followed by the aerial oxidation of the precipitate, the Co cations were found to be divalent, whereas trivalent Co was incorporated into the goethite obtained by ageing a solution containing Fe(III) and Co(II) cations precipitated by the addition of KOH. This different behavior is explained by the higher pH of goethite formation in the latter case, which favors the oxidation of the Co(II) cations.
Development of Miniaturized Competitive Immunoassays on a Protein Chip as a Screening Tool for Drugs
Authors: Du Hongwu , Wu Moutian , Yang Weiping , Yuan Gu , Sun Yimin , Lu Yuan , Zhao Shan , Du Qingyun , Wang Jun , Yang Sheng , Pan Mangen , Lu Ying , Wang Shan , Cheng Jing
Published: November 2004

Background: Doping in sports has become a serious problem. Gas chromatography–mass spectrometry (GC-MS) serves as an effective reference method, but it is limited by low throughput and is therefore not suitable for large-scale screening. Use of protein chips for high-throughput screening of all athletes for prohibited substances could become an important complementary tool to GC-MS.

Methods: We developed a protein chip based on an aldehyde-activated glass slide containing 10 physically isolated arrays. The chip was used to screen urine from 1347 athletes for prohibited substances and to screen a negative control group consisting of 200 females and 120 males. Urine samples from 66 individuals known to be abusers, provided by the China Doping Control Center (CDCC), and 129 standard prohibited substances were tested as positive controls.

Results: All 1347 urine samples screened by means of the protein chips were also subjected to reference analysis by GC-MS at the CDCC. There was no qualitative difference between the results obtained with the two methods. The correlation coefficient (r2) for the quantitative results obtained with the protein chip and GC-MS was 0.991.

Conclusions: The protein chip could be used to screen for a series of 16 prohibited drugs in urine samples. This system has the potential to become an effective screening method to test substances prohibited by the International Olympic Committee.
Electron‐beam modification of nitrile rubber in the presence of polyfunctional monomers
Authors: Vijayabaskar V. , Bhowmick Anil K.
Published: November 2004

The structural changes of nitrile rubber in both the presence and the absence of polyfunctional monomers, such as trimethylolpropane triacrylate (TMPTA), tripropyleneglycol diacrylate (TPGDA), and trimethylolmethane tetraacrylate (TMMT), at different doses of electron beam irradiations, were investigated with the help of FTIR spectroscopy (in the ATR mode), solid‐state NMR, dynamic mechanical thermal analysis, and sol–gel analysis. There was a significant decrease in the concentration of olefinic groups for modified system with 3% TMPTA compared to that of the unmodified nitrile rubber on irradiation. This was also confirmed by the increase in the carbon resonances attributed to CC linkages from solid‐state NMR for the modified system, indicating more crosslinkages. The increase in crosslinking was also revealed by the increase in % gel content and dynamic storage moduli with radiation dose. The lifetime of spurs formed and the critical dose, an important criterion for overlapping of spurs, were determined for both grafted and ungrafted nitrile rubber using a mathematical model. The ratio of scissioning to crosslinking for nitrile rubber was determined using the Charlesby–Pinner equation. Mechanical properties were studied for the modified and the unmodified systems and the tensile strength was found to increase with grafting of polyfunctional monomers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 435–447, 2005
Receptor‐Assisted Combinatorial Chemistry: Thermodynamics and Kinetics in Drug Discovery
Authors: Cheeseman Jeremy D. , Corbett Andrew D. , Gleason James L. , Kazlauskas Romas J.
Published: November 2004

Current drug discovery using combinatorial chemistry involves synthesis followed by screening, but emerging methods involve receptor‐assistance to combine these steps. Adding stoichiometric amounts of receptor during library synthesis alters the kinetics or thermodynamics of the synthesis in a way that identifies the best‐binding library members. Three main methods have emerged thus far in receptor‐assisted combinatorial chemistry: dynamic combinatorial libraries, receptor‐accelerated synthesis, and a new method, pseudo‐dynamic libraries. Pseudo‐dynamic libraries apply both thermodynamics and kinetics to amplify library members to easily observable levels, and attain selectivity heretofore unseen in receptor‐assisted systems.
Solution Conformation and Dynamics of the Ion Pairs Originating from the Reaction of B(C6F5)3 with Bisindenyl Dimethyl Zirconium Complexes
Authors: Beringhelli Tiziana , D'Alfonso Giuseppe , Maggioni Daniela , Mercandelli Pierluigi , Sironi Angelo
Published: November 2004

The two ion pairs [(4,7‐Me2indenyl)2ZrMe]+[MeB(C6F5)3]− (1 b) and [(indenyl)2ZrMe]+ [MeB(C6F5)3]− (2 b) have been generated in situ by reaction of stoichiometric B(C6F5)3 with the corresponding dimethyl zirconocenes. It has been shown that molecular mechanics computations, guided by experimental 1H/1H NOE correlations, can provide information on the conformers present in solution. The dynamics of the ion pairs has also been investigated, showing the occurrence of both the processes previously characterized for this class of compounds, namely the B(C6F5)3 migration between the two methyl groups and dissociation–recombination of the whole [MeB(C6F5)3]− anion, the latter process being much faster than the first one (about three order of magnitude). Moreover, it has been shown that in certain conditions intermolecular processes can occur, which mimic the above‐mentioned dissociative exchanges. In particular, the presence of species containing loosely bound [MeB(C6F5)3]− anion fastens the exchange of this anion, while the presence of free B(C6F5)3 accelerates its exchange between the two methyl sites.
An Asymmetric Formal Synthesis of Fasicularin
Authors: Fenster Michaël D. B. , Dake Gregory R.
Published: November 2004

An asymmetric formal synthesis of fasicularin (1) is described. This natural product, isolated from the extracts of the marine invertebrate Nephteis fasicularis, has shown modest cytotoxicity towards Vero cells. Fasicularin is among only two members of the cylindricine family of natural products, along with lepadiformine (2), to possess a trans A–B ring junction. Key steps of this approach to 1 involve a siloxy‐epoxide semipinacol rearrangement of 5 to 6, a B‐alkyl Suzuki–Miyaura coupling reaction by using enol trifluoromethanesulfonate 19 and a substrate‐directed hydrogenation reaction of 24. This formal synthesis also highlights the difficulty in the incorporation of the thiocyanate functionality present in 1.
7‐Azaindolyl‐ and 2,2′‐Dipyridylamino‐Functionalized Molecular Stars with Sixfold Symmetry: Self‐Assembly, Luminescence, and Coordination Compounds
Authors: Jia Wen‐Li , Wang Rui‐Yao , Song Datong , Ball Steven J. , McLean Alastair B. , Wang Suning
Published: November 2004

Two novel star molecules functionalized with 7‐azaindolyl and 2,2′‐dipyridylamino groups have been synthesized. Both molecules possess a sixfold rotation symmetry. Molecule L 1 is based on the hexaphenylbenzene core with the formula of hexa[p‐(7‐azaindolyl)phenyl]benzene, while molecule L 2 is based on the hexakis(biphenyl)benzene core with the formula of hexa[p‐(2,2′‐dipyridylamino)biphenyl]benzene. Both compounds have been characterized by single‐crystal X‐ray diffraction analyses. Molecule L 1 forms extended two‐dimensional layered structure, while L 2 forms interpenetrating columnar stacks in the solid state, as revealed by X‐ray diffraction analyses. Nanowire structures based on columnar stacks through self‐assembly of L 2 on a graphite surface were revealed by an STM study. Molecules L 1 and L 2 are capable of binding to metal ions, resulting in unusual structural motifs. Two AgI complexes with the formulae of [(AgNO3)2(L 1)] (1) and [(AgNO3)3(L 1)] (2) were isolated from the reactions of AgNO3 with L 1. Compound 1 displays extended intermolecular π–π stacking interactions that are responsible for its extended two‐dimensional structure in the crystal lattice. Complex 2 has a “bowl” shape and forms polar stacks in the crystal lattice. A CuII complex with the formula of [{Cu(NO3)2}6(L 2)] (3) was isolated from the reaction of Cu(NO3)2 with compound L 2. The six CuII ions in 3 are chelated by the 2,2′‐dipyridylamino groups of the star ligand L 2. Intermolecular CuO (nitrate) bonds lead to the formation of an extended two‐dimensional coordination network of 3. Both L 1 and L 2 are blue luminescent. Their interactions with AgI or CuII cause drastic quenching of emission. In addition, the luminescence of L 1 and L 2 is sensitive to the presence of protons, which cause a reduction of emission intensity and a red shift of the emission energy.
Shape‐Controlled Synthesis of Metal Nanostructures: The Case of Silver
Authors: Wiley Benjamin , Sun Yugang , Mayers Brian , Xia Younan
Published: November 2004

The concept of shape‐controlled synthesis is discussed by investigating the growth mechanisms for silver nanocubes, nanowires, and nanospheres produced through a polymer‐mediated polyol process. Experimental parameters, such as the concentration of AgNO3 (the precursor to silver), the molar ratio between poly(vinylpyrrolidone) (PVP, the capping agent) and AgNO3, and the strength of chemical interaction between PVP and various crystallographic planes of silver, were found to determine the crystallinity of seeds (e.g., single crystal versus decahedral multiply twinned particles). In turn, the crystallinity of a seed and the extent of the PVP coverage on the seed were both instrumental in controlling the morphology of final product. The ability to generate silver nanostructures with well‐defined morphologies provides a great opportunity to experimentally and systematically study the relationship between their properties and geometric shapes.
Linear Unsaturated Polyamides: Nylons 6 u18 and 18 u18
Authors: Bennett Carl , Mathias Lon J.
Published: November 2004

Summary: Linear unsaturated nylons 6 u18 and 18 u18 have been made containing a double bond in the center of the diacid segment with potential for additional functionalization. Solution state NMR showed the presence of a small portion of cis amide units. Solid state NMR verified the presence of the double bond in the bulk, and that the polyamides were present in the α‐crystalline form. Thermal stability was comparable to linear saturated nylons, and the melting and crystallization temperatures of the unsaturated nylons were lower compared to the saturated analogs.

DSC heating and cooling thermograms for nylons 6 u18 and 18 u18.

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DSC heating and cooling thermograms for nylons 6 u18 and 18 u18.
ATRP of Allyl Methacrylate with Alkyl Methacrylates – Crosslinking of Poly(methacrylate)s with Allyl Ester Side Groups
Authors: Mennicken Martina , Nagelsdiek René , Keul Helmut , Höcker Hartwig
Published: November 2004

Summary: Random copolymers of methyl methacrylate (MMA), butyl methacrylate (BMA) and allyl methacrylate (AMA) were prepared via atom transfer radical polymerization (ATRP). AMA is a bifunctional monomer with two double bonds of different reactivity: a highly reactive methacrylate double bond and an allyl ester double bond of lower reactivity. In order to obtain linear polymers with pendant allyl ester groups, the copolymerization conditions have to be optimized with respect to the concentration of AMA, the catalyst system applied – especially the ligand – and the temperature. By means of kinetic studies the reaction parameters for a controlled polymerization were determined. The results obtained show that the higher the temperature and the amount of AMA is the higher is the probability of irregular chain growth and side reactions induced by the pendant allyl ester groups such as hydrogen abstraction from the allyl position or radical addition to the allyl ester double bond. The random copolymers were photochemically crosslinked by using 2,2‐dimethoxy‐2‐phenylacetophenone as photoinitiator. The thermal properties of linear and crosslinked polymers were determined. The glass transition temperatures of both show no significant difference at low AMA content and thus low crosslinking densities.

GPC eluograms of MMA/BMA (70:30) copolymers with 5 mol‐% AMA at different conversions.

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GPC eluograms of MMA/BMA (70:30) copolymers with 5 mol‐% AMA at different conversions.
Effective fractal dimensions
Authors: Lutz Jack H.
Published: November 2004

Classical fractal dimensions (Hausdorff dimension and packing dimension) have recently been effectivized by (i) characterizing them in terms of real‐valued functions called gales, and (ii) imposing computability and complexity constraints on these gales. This paper surveys these developments and their applications in algorithmic information theory and computational complexity theory. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Countable sums and products of metrizable spaces in ZF
Authors: Keremedis Kyriakos , Tachtsis Eleftherios
Published: November 2004

We study the role that the axiom of choice plays in Tychonoff's product theorem restricted to countable families of compact, as well as, Lindelöf metric spaces, and in disjoint topological unions of countably many such spaces. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integration of PV systems on health emergency vehicles. The FIVE project
Authors: Almonacid G. , Muñoz F. J. , de la Casa J. , Aguilar J. D.
Published: November 2004

The main purpose of this paper is to present the FIVE Project (Fotovoltaico Integrado en Vehículos de Emergencias) which involves the integration of a photovoltaic system in a health emergency vehicle. Here, the use of photovoltaic technology is extended to improving the performance of these kinds of vehicles. The fact is that their batteries usually deteriorate prematurely, owing to the high electrical consumption of the medical equipment they have to support, together with the short periods of time that their engines remain running. A consequence of such problems is high maintenance costs due to the frequent changes of batteries, and what is more important, occasional difficulties in starting the vehicle at critical moments. Furthermore, the service battery of the health emergency vehicle has to be charged every day by a battery charger connected to the grid, providing this kind of vehicle a poor autonomy level. In order to solve these problems, the main purpose of this project was to design, implement and evaluate the performance and utility of a health emergency vehicle prototype with an integrated PV generator. The data collected from the prototype evaluation tests have shown that the incorporation of the PV generator solves the problems mentioned above. Besides, the relative cost of the PV generator compared with the high cost of health emergency vehicles can be considered negligible. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of heat treatment on nanocrystalline formations in Fe40Ni40(Si + B)19Mo1–2 amorphous ribbon
Authors: Saiseng S. , Winotai P. , Limsuwan P.
Published: November 2004

Effects of heat treatment on Fe40Ni40(Si+ B)19Mo1–2 were monitored by Mössbauer spectroscopy (MR), X‐ray diffraction (XRD) and differential scanning calorimetry (DSC). Mössbauer spectra were fitted by using the PC‐MOS II program to obtain such parameters as hyperfine field, isomer shift and quadrupole splitting of samples annealed for two hours in argon at different temperatures. The change in direction of local magnetization and the transformation of amorphous to crystalline phase were observed. Heat treatments near the crystallization temperature between 450–500 °C resulted in nanograins of α‐Fe, α‐Fe(Si) and t‐Fe2B embedded in the remaining uncrystallized amorphous matrix. DSC data showed that the ribbon exhibited two‐step crystallizations at 454 °C and 525 °C, respectively. The first crystalliza‐ tion corresponded mainly to soft ferromagnetic α‐Fe, α‐Fe(Si) and some minor t‐Fe2B phase forma‐ tions, while the second, corresponded to t‐Fe3B phase. Further heat treatment at 600 °C led to complete crystallizations at which the ferromagnetic phases α‐Fe and α‐Fe(Si) transformed to a paramagnetic phase fcc‐FeNi, and ferromagnetic phases of c‐FeNi3, t‐Fe2B, t‐Fe3B, and Ni2Si, respectively. Due to the high mag‐netic anisotropy of t‐Fe2B and other phases as well as to keep the crystallites in the nano region, the Fe40Ni40(Si‐B)19Mo1–2 ribbon should not be heated above 500 °C for the superior magnetic properties. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Surface structural analysis of monolayer films composed of light elements by x‐ray photoelectron diffraction
Authors: Nakamura H. , Fujihara N. , Nojima M. , Tamura K. , Ishii H. , Owari M. , Oshima C. , Nihei Y.
Published: November 2004

For surface structural analysis on monolayer films composed of light elements, we investigated theoretical x‐ray photoelectron diffraction (XPED) patterns from single‐molecule adsorbing surfaces by using both Cr Lα (572.8 eV) and Al Kα (1486.6 eV) excitations. Forward‐scattering peaks and Kikuchi‐like bands were clearly observed in the pattern excited by Al Kα. In contrast, the features of the XPED patterns excited by Cr Lα were more diffuse. However, the circular patterns excited by Cr Lα are clearer than those excited by Al Kα. This result suggests that the use of a lower energy x‐ray source improves XPED structural analysis on ultrathin films composed of light elements. Copyright © 2004 John Wiley & Sons, Ltd.
Interval estimation of the proportion ratio under multiple matching
Authors: Lui Kung‐Jong
Published: November 2004

The discussions on interval estimation of the proportion ratio (PR) of responses or the relative risk (RR) of a disease for multiple matching have been generally focused on the odds ratio (OR) based on the assumption that the latter can approximate the former well. When the underlying proportion of outcomes is not rare, however, the results for the OR would be inadequate for use if the PR or RR was the parameter of our interest. In this paper, we develop five asymptotic interval estimators of the common PR (or RR) for multiple matching. To evaluate and compare the finite sample performance of these estimators, we apply Monte Carlo simulation to calculate the coverage probability and the average length of the resulting confidence intervals in a variety of situations. We note that when we have a constant number of matching, the interval estimator using the logarithmic transformation of the Mantel–Haenszel estimator, the interval estimator derived from the quadratic inequality given in this paper, and the interval estimator using the logarithmic transformation of the ratio estimator can consistently perform well. When the number of matching varies between matched sets, we find that the interval estimator using the logarithmic transformation of the ratio estimator is probably the best among the five interval estimators considered here in the case of a small number (=20) of matched sets. To illustrate the use of these interval estimators, we employ the data studying the supplemental ascorbate in the supportive treatment of terminal cancer patients. Copyright © 2004 John Wiley & Sons, Ltd.
When using knowledge can hurt performance: the value of organizational capabilities in a management consulting company
Authors: Haas Martine R. , Hansen Morten T.
Published: November 2004

This paper explores the possibility that utilizing the firm's knowledge resources to complete important tasks can backfire and undermine competitive performance. Drawing on organizational capabilities and knowledge‐sharing research, we develop a situated performance view that holds that the value of obtaining and using knowledge within a firm depends on the task situation. Using a data set of 182 sales proposals for client work in a management consulting company, we show that sales teams that had varying needs to learn and differentiate themselves from competitors derived different levels of value from obtaining and using electronic documents and advice from colleagues. Highly experienced teams were more likely than inexperienced teams to lose the sales bids if they utilized such knowledge. Teams that had a high need to differentiate themselves from competitors also had a lower chance of winning if they utilized electronic documents. There were situations, however, where teams performed better if they utilized the firm's knowledge resources. These results suggest that competitive performance depends not on how much firms know but on how they use what they know. Copyright © 2004 John Wiley & Sons, Ltd.
Revisiting the Miles and Snow strategic framework: uncovering interrelationships between strategic types, capabilities, environmental uncertainty, and firm performance
Authors: DeSarbo Wayne S. , Anthony Di Benedetto C. , Michael Song  , Sinha Indrajit
Published: November 2004

The Miles and Snow strategic type framework is re‐examined with respect to interrelationships with several theoretically relevant batteries of variables, including SBU strategic capabilities, environmental uncertainty, and performance. A newly developed constrained, multi‐objective, classification methodology is modified to empirically derive an alternative quantitative typology using survey data obtained from 709 firms in three countries (China, Japan, United States). We compare the Miles and Snow typology to the classification empirically derived utilizing this combinatorial optimization clustering procedure. With respect to both variable battery associations and objective statistical criteria, we show that the empirically derived solution clearly dominates the traditional P‐A‐D‐R typology of Miles and Snow. Implications and directions for future research are provided. Copyright © 2004 John Wiley & Sons, Ltd.
Achieving proportional delay differentiation in wireless LANviacross‐layer scheduling
Authors: Xue Yuan , Chen Kai , Nahrstedt Klara
Published: November 2004

Providing service differentiation in wireless networks has attracted much attention in recent research. Existing studies so far have focused on the design of differentiated media access algorithms. Some quality of service (QoS) metrics, such as queueing delay cannot be completely addressed by these approaches. Moreover, without a formalized service differentiation goal that quantifies the outcome of differentiation, the performance of most of the approaches fluctuates, especially in short time‐scales.

This paper addresses above problems by introducing the concept of proportional service differentiation, to the domain of wireless network and focuses on providing proportional delay differentiation in wireless LANs. Due to the unique characteristic of distributed medium sharing, the scheduling algorithm employed in wireline networks can not be applied directly to the context of wireless LANs. We argue that delay differentiation in wireless LAN can only be achieved through a joint packet scheduling at the network layer and distributed coordination at the media access control (MAC) layer. Therefore, we present a cross‐layer waiting time priority (CWTP) scheduling algorithm. CWTP consists of two tiers: an intra‐node waiting time priority (WTP) scheduler at the network layer and an inter‐node distributed coordination function at the MAC layer. These two tiers coordinateviaa mapping function, which maps the normalized waiting time at the network layer to the backoff time at the MAC layer. Two mapping schemes, namely linear mapping and piecewise linear mapping, are presented and evaluated in this paper. Extensive simulation results show that the CWTP algorithm can effectively achieve proportional delay differentiation in wireless LANs. Copyright © 2004 John Wiley & Sons, Ltd.
Performance analysis of IEEE 802.11 MAC protocols in wireless LANs
Authors: Zhai Hongqiang , Kwon Younggoo , Fang Yuguang
Published: November 2004

IEEE 802.11 MAC protocol is the de facto standard for wireless local area networks (LANs), and has also been implemented in many network simulation packages for wireless multi‐hop ad hoc networks. However, it is well known that, as the number of active stations increases, the performance of IEEE 802.11 MAC in terms of delay and throughput degrades dramatically, especially when each station's load approaches its saturation state. To explore the inherent problems in this protocol, it is important to characterize the probability distribution of the packet service time at the MAC layer. In this paper, by modeling the exponential backoff process as a Markov chain, we can use the signal transfer function of the generalized state transition diagram to derive an approximate probability distribution of the MAC layer service time. We then present the discrete probability distribution for MAC layer packet service time, which is shown to accurately match the simulation data from network simulations. Based on the probability model for the MAC layer service time, we can analyze a few performance metrics of the wireless LAN and give better explanation to the performance degradation in delay and throughput at various traffic loads. Furthermore, we demonstrate that the exponential distribution is a good approximation model for the MAC layer service time for the queueing analysis, and the presented queueing models can accurately match the simulation data obtained from ns‐2 when the arrival process at MAC layer is Poissonian. Copyright © 2004 John Wiley & Sons, Ltd.
On the squeeze effect of lubricants with additives between rough porous rectangular plates
Authors: Naduvinamani N.B. , Fathima S.T. , Hiremath P.S.
Published: November 2004

This paper describes a theoretical analysis of the combined effects of unidirectional surface roughness and the lubricant additives on the performance characteristics of a porous squeeze film lubrication between two rectangular plates of finite dimensions. The lubricant with microstructure additives is modeled as a Stokes couplestress fluid. The stochastic Reynolds type equation is derived to account for the effects due to surface roughness and lubricant additives. The problem is solved analytically using the stochastic method developed by Christensen. It is found that, there exists a critical value of the aspect ratio above which the roughness effects are pronounced due to the size effects of the lubricant additives. Further, this critical value is dependent on the microstructure size of additives. The coarser the microstructure, higher is the critical value of the aspect ratio.
Habitat and population estimates of some threatened lowland forest bird species in Tambopata, south-east Peru
Authors: LLOYD HUW
Published: November 2004

Surveys of threatened lowland forest bird species and forest habitats were conducted during a 21-month census of lowland bird communities in Tambopata, Department of Madre de Dios, south-east Peru. A combination of distance sampling census methods and direct counts was used for the census in five sites located along the Rio Madre de Dios and Rio Tambopata. All five sites consisted of different forest types with significantly different habitat components. Three of these sites were classified as primary forest habitats whilst the remaining two were classified as disturbed forests. Population densities were calculated for eight of the threatened species recorded during the census. Density estimates of non-bamboo specialists were higher in primary forest habitats than in disturbed forest habitats. Density estimates of most bamboo specialists were higher in primary Old Floodplain forest with extensive bamboo understorey than in primary Middle/Upper Floodplain forest with smaller, patchy areas of bamboo understorey. Calculation of regional population estimates based on the amount of forest cover from satellite photographs shows that only two of the threatened bird species have substantial populations currently protected by the Parque Nacional Bahuaja-Sonene and Reservada Nacional de Tambopata. Selective logging operations that reduce overall tree biomass and remove a large proportion of palm tree species from primary forest habitats will have an adverse affect on local populations of four of the threatened bird species in the region.
The avifauna of the Vietnamese Mekong Delta
Authors: BUCKTON SEBASTIAN T. , SAFFORD ROGER J.
Published: November 2004

The Vietnamese Mekong Delta has undergone much anthropogenic change in the last 100 years, and few areas of natural or semi-natural habitat remain. Despite the likely consequent loss of biodiversity, little documentation exists about the region's avifauna at any time in its history. Here, we present a review of the avifauna of the Vietnamese part of the Mekong delta based on various surveys and other fieldwork carried out since 1988, and an assessment of the few earlier data that were available. A total of 247 species has been recorded from the Vietnamese delta since 1988. Most pre-war data are now considered to be of uncertain validity. Some 50% of the species recorded since 1988 are dependent on wetlands. Of these, 20 are listed as globally threatened or Near Threatened. The delta supports, or is likely to support, internationally important numbers of 21 species of waterbird, including two threatened and three Near Threatened species. Annotations are provided for records of globally or regionally threatened species; for those species for which the Mekong Delta holds internationally important numbers; and those for which records described herein constitute range extensions. Information on the avifauna of the Mekong Delta presented here suggests it is of regional and global importance for the maintenance of wetland biodiversity.
International support for environmental protection
Authors: ISRAEL DEBRA K.
Published: November 2004

This paper uses household-level survey data from a 1989 Harris poll conducted in 12 developing and three developed countries to examine the empirical relationship between the support for paying higher taxes for environmental protection and per capita national income. Results from ordered probit estimation suggest that as per capita real gross domestic product rises, controlling for other household characteristics, the strength of the support for somewhat higher taxes for environmental protection is falling for low-income countries and rising for high-income countries. The evidence also suggests that environmental protection may be important to people in developing countries during the process of economic growth. The high level of support for environmental protection found among the lower-income African countries included in this study is one result that warrants additional research. Higher economic growth rates are also found to be associated with greater support for environmental protection.
Emotions in a Body Plethysmograph
Authors: von Leupoldt Andreas , Dahme Bernhard
Published: November 2004

Abstract: The role of strong emotions in eliciting asthmatic exacerbations has been discussed in psychosomatic theory for decades. This relationship has mostly been studied in asthmatic individuals, while healthy control groups have received limited attention. Measuring procedures have partially been held responsible for conflicting results. We tested a new laboratory method on 20 healthy volunteers to examine the influence of emotions on airway obstructions. Short affective states were induced by presenting a negative (sadness), a positive (amusement), and a neutral movie clip lasting about 2 min with participants being seated in the glass box of a whole body plethysmograph - the gold standard for measuring airway resistance (Raw). Raw, specific airway resistance (sRaw), and thoracic gas volume (TGV) were measured in a baseline condition and immediately after each video presentation; in addition, sRaw was measured before and during each clip presentation. Based on subjects' ratings, the relevant affective states were successfully induced, while no specific state was provoked by the neutral movie. Airway obstructions, expressed as increases of sRaw, were observed during both the negative and positive clip but also in the neutral condition. No substantial effect of mood induction on Raw and TGV was obtained. The findings show a nonspecific effect of watching affective film clips on airway obstruction as measured by whole body plethysmography. Recommendations for a modified experimental protocol are given for future studies using this technique as a promising method.
Relationship Between Visual and Kinesthetic Imagery, Field Dependence-Independence, and Complex Motor Skills
Authors: Guillot A. , Collet C. , Dittmar A.
Published: November 2004

Abstract: Visual imagery (VI) involves self-visualization of action, whereas kinesthetic imagery (KI) implies somesthetic sensations elicited by action. Motor imagery (MI) has been shown to enhance motor performance but inconsistent results were obtained depending on the respective impacts of VI and KI. It is hypothesized here that the type of MI may interact with individual characteristics such as field dependence-independence. As subjects' movements can be mainly checked out through exteroceptive or proprioceptive information, task requirements were also expected to influence MI. Witkin's Group Embedded Figures Test was implemented with two groups (n1 = 10 gymnasts, n2 = 10 tennis players). Athletes were asked to imagine a complex motor skill by alternate use of VI and KI. Skin resistance was selected as a peripheral indicator of MI and recorded continuously. Autonomic responses were compared by computing the VI/KI ratio. Results taking both the field-dependence test and MI type into account were not as clear as expected. As hypothesized, gymnasts were more field-independent than tennis players. VI/KI ratio analysis showed that a similar pattern was observed in the gymnasts group (ratio close to 1.0), whatever the type of imagery. This suggests that gymnasts are equally able to perform VI and KI. Fifty percent of the tennis players group showed a ratio higher than 1.0, suggesting that VI was more effective than KI. Conversely, the remaining 50% showed a below-1.0 ratio, suggesting more effective KI. Thus, some tennis players may make better use of VI than KI, and conversely some may make better use of KI than VI. These results indicate that MI training may be relatively independent of task requirements and be based mainly upon individual characteristics such as MI abilities. Finally, results indicate systematic overestimation in self-estimation of movement duration during MI, which was greater during KI than during VI, suggesting that athletes have greater trouble in feeling than in visualizing movement.
Relating cultivar resistance to sugarcane yield using breeding selection trial analyses; orange rust and yellow spot
Authors: Magarey R. C. , Bull J. I. , Neilsen W. A. , Camilleri J. R. , Magnanini A. J.
Published: November 2004

Plant breeders in the Australian sugar industry conduct yield assessment trials each year to assess the yielding ability of clones in the sugarcane breeding programme. Several endemic diseases impinge on the yield of these clones and the tested clones vary greatly in disease susceptibility. In this study, resistance to the diseases orange rust and yellow spot was assessed in final stage trials in the Northern Queensland programme. Clonal yielding ability was related to disease resistance. The results indicate that both diseases, but particularly yellow spot, influenced the yield (tonnes cane/ha and tonnes sugar/ha) of clones in northern breeding trials in 2000. Yield loss estimates were calculated, as well as the relationship between resistance and yield. There was a high level of resistance to orange rust in clones in these trials but much less resistance to yellow spot; the resistance index or orange rust was 2.2 while for yellow spot it was 5.5. Yield loss resistance index values of 5.0 and above for orange rust suggest there is adequate resistance in clones to minimise losses from this disease. In contrast, the yield loss resistance index for yellow spot (tonnes cane/ha) was below 5.0, therefore, it is concluded that during the 2000 harvest season, there was inadequate resistance to minimise losses. The information gathered from this research will be used to determine the level of leaf disease resistance needed in commercial cultivars to optimise yielding ability. Such decisions should improve the efficiency of selection and the performance of commercial cultivars in the Australian sugar industry.
Grain yield production in relation to plant growth of wheat and canola following clover pastures in southern Victoria
Authors: Zhang X. , Evans P. M.
Published: November 2004

The plant growth and grain yield of crops following a pasture phase in 1:1 pasture–crop rotations were studied in southern Victoria in 2001 (wheat and canola at Hamilton, and wheat at Streatham and Gnarwarre). Both the wheat and canola crops produced high grain yields with no application of nitrogen fertiliser.
In experiment 1 (at Hamilton) where the crops were dependent on nitrogen input from subterranean clover pasture, canola produced 4.1 t/ha of grain and wheat averaged 6.0 t/ha. The 3 canola cultivars (Charlton, Mystic and Surpass 400) had similar grain yields. However, for wheat, the late-maturing spring wheat cv. Kellalac and the early-maturing spring wheat cv. Silverstar produced significantly higher grain yields (6.6 and 6.3 t/ha, respectively) than the late-maturing winter cv. Brennan (5.0 t/ha). The 3 cultivars of each crop differed markedly in their major yield components. The most striking differences were those shown by Silverstar, which had the highest yield, together with Kellalac, but had lower biomass and lower leaf area index than the 2 late-maturing wheats. Silverstar compensated by having 50% more grains per head than the late-maturing Brennan. While Silverstar flowered on average 34 days earlier than the 2 other wheats, it took some 3 weeks longer to mature after anthesis.
In experiment 2, the wheat crop (cv. Silverstar) produced grain yields of 5.4 t/ha over 6 different treatments, with higher grain yields at Streatham (6.1 t/ha) than at Gnarwarre (4.7 t/ha). Across the 2 sites, the grain yields following clovers reached over 5.7 t/ha, in contrast with low grain yields from the continuous crop (3.7 t/ha) and fallow/crop treatments (3.7 t/ha). Grain yields were closely related to the herbage dry matter production of previous pasture legumes, indicating a positive crop response. This may, in turn, reflect the nutrient status of the treatments, particularly the nitrogen status.
Diazinon and diflubenzuron residues in soil following surface disposal of spent sheep dip wash
Authors: Levot G. W. , Lund R. D. , Black R.
Published: November 2004

Spent sheep dip wash (4000 L) containing 70 mg diazinon/L and sludge containing 320 mg diazinon/L were disposed onto a 450 m2 site designated for this purpose. After 14 days soil residues were less than 1 mg/kg. Diflubenzuron residues on a similar site following disposal of 5200 L of spent dip wash containing 370 mg/L remained at about 40 mg/kg for a month after disposal and were still about 6 mg/kg 12 months later. Results indicated that the half-lives in soil of diazinon and diflubenzuron from spent dip wash were about 9 and 117 days, respectively. We recommend disposing spent sheep dips on to bunded areas of flat, vegetated land isolated from sensitive areas such as watercourses and from which animals can be excluded. Area quarantine for up to 3 months might be adequate for diazinon-based products but we recommend excluding animals permanently from sites used for the disposal of diflubenzuron-based dips. Alternatively, more sophisticated methods of bioremediation of dip disposal sites may be preferred.
Ginger (Zingiber officinale) autotetraploids with improved processing quality produced by an in vitro colchicine treatment
Authors: Smith M. K. , Hamill S. D. , Gogel B. J. , Severn-Ellis A. A.
Published: November 2004

Ginger autotetraploids were produced by immersing shoot tips in a 0.5% w/v colchicine, 2% v/v dimethyl sulfoxide solution for 2 h. Stomatal measurements were used as an early indicator of ploidy differences in culture with mean stomata length of tetraploids (49.2 μm) being significantly larger than the diploid (38.8 µm). Of the 500 shoot tips treated, 2% were characterised as stable autotetraploid lines following field evaluation over several seasons. Results were confirmed with flow cytometry and, of the 7 lines evaluated for distinctness and uniformity, 6 were solid tetraploid mutants and 1 was a periclinal chimera. Significant differences were noted between individual tetraploid lines in terms of shoot length, leaf length, leaf width, size of rhizome sections (knob weight) and fibre content. The solid autotetraploid lines had significantly wider, greener leaves than the diploids, they had significantly fewer but thicker shoots and, although ‘Queensland’ (the diploid parent from which the tetraploids were derived) had a greater total rhizome mass at harvest, its knob size was significantly smaller. From the autotetraploid lines, one line was selected for commercial release as ‘Buderim Gold’. It compared the most favourably with ‘Queensland’ in terms of the aroma/flavour profile and fibre content at early harvest, and had consistently good rhizome yield. More importantly it produced large rhizome sections, resulting in a higher recovery of premium grade confectionery ginger and a more attractive fresh market product.
Liver-targeted disruption ofApcin mice activates β-catenin signaling and leads to hepatocellular carcinomas
Authors: Colnot S. , Decaens T. , Niwa-Kawakita M. , Godard C. , Hamard G. , Kahn A. , Giovannini M. , Perret C.
Published: November 2004

Although inappropriate activation of the Wnt/β-catenin pathway has been implicated in the development of hepatocellular carcinoma (HCC), the role of this signaling in liver carcinogenesis remains unclear. To investigate this issue, we constructed a mutant mouse strain,Apclox/lox, in which exon 14 of the tumor-suppressor gene adenomatous polyposis coli (Apc) is flanked byloxPsequences. i.v. injection of adenovirus encoding Cre recombinase (AdCre) at high multiplicity [109plaque-forming units (pfu) per mouse] inactivated theApcgene in the liver and resulted in marked hepatomegaly, hepatocyte hyperplasia, and rapid mortality. β-Catenin signaling activation was demonstrated by nuclear and cytoplasmic accumulation of β-catenin in the hepatocytes and by the induction of β-catenin target genes (glutamine synthetase, glutamate transporter 1, ornithine aminotransferase, and leukocyte cell-derived chemotaxin 2) in the liver. To test a long-term oncogenic effect, we inoculated mice with lower doses of AdCre (0.5 × 109pfu per mouse), compatible with both survival and persistence of β-catenin-activated cells. In these conditions, 67% of mice developed HCC. β-Catenin signaling was strongly activated in theseApc-inactivated HCCs. The HCCs were well, moderately, or poorly differentiated. Indeed, their histological and molecular features mimicked human HCC. Thus, deletion ofApcin the liver provides a valuable model of human HCC, and, in this model, activation of the Wnt/β-catenin pathway by invalidation ofApcis required for liver tumorigenesis.
Printed covalent glycan array for ligand profiling of diverse glycan binding proteins
Authors: Blixt Ola , Head Steve , Mondala Tony , Scanlan Christopher , Huflejt Margaret E. , Alvarez Richard , Bryan Marian C. , Fazio Fabio , Calarese Daniel , Stevens James , Razi Nahid , Stevens David J. , Skehel John J. , van Die Irma , Burton Dennis R. , Wilson Ian A. , Cummings Richard , Bovin Nicolai , Wong Chi-Huey , Paulson James C.
Published: November 2004

Here we describe a glycan microarray constructed by using standard robotic microarray printing technology to couple amine functionalized glycans to an amino-reactive glass slide. The array comprises 200 synthetic and natural glycan sequences representing major glycan structures of glycoproteins and glycolipids. The array has remarkable utility for profiling the specificity of a diverse range of glycan binding proteins, including C-type lectins, siglecs, galectins, anticarbohydrate antibodies, lectins from plants and microbes, and intact viruses.
The Role of the Kinesin Motor KipA in Microtubule Organization and Polarized Growth ofAspergillus nidulans
Authors: Konzack Sven , Rischitor Patricia E. , Enke Cathrin , Fischer Reinhard
Published: November 2004

Polarized growth in filamentous fungi requires the integrity of the microtubule (MT) cytoskeleton. We found that growing MTs in Aspergillus nidulans merge at the center of fast growing tips and discovered that a kinesin motor protein, KipA, related to Tea2p of Schizosaccharomyces pombe, is required for this process. In a ΔkipA strain, MT plus ends reach the tip but show continuous lateral movement. Hyphae lose directionality and grow in curves, apparently due to mislocalization of the vesicle supply center (Spitzenkörper) in the apex. Green fluorescent protein (GFP)-KipA accumulates at MT plus ends, whereas a KipA rigor mutant protein, GFP-KipAG223E, coated MTs evenly. These findings suggest that KipA requires its intrinsic motor activity to reach the MT plus end. Using KipA as an MT plus-end marker, we found bidirectional organization of MTs and determined the locations of microtubule organizing centers at nuclei, in the cytoplasm, and at septa.