bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiclass composite N‐gram language model based on connection direction
Authors: Yamamoto Hirofumi , Sagisaka Yoshinori
Published: October 2004

The authors propose a method to generate a compact, highly reliable language model for speech recognition based on the efficient classification of words. In this method, the connectedness with the words immediately before and after the word is taken to represent separate attributes, and individual classification is performed for each word. The resulting composite word class is created separately based on the distribution of words connected before or after. As a result, classification of classes is efficient and reliable. In a multiclass composite N‐gram, which uses the proposed method for the variable‐order N‐gram to bring in chain words, the entry size is reduced to one‐tenth, and the word recognition rate is higher than that of a conventional composite N‐gram for particles or variable‐length word arrays. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(7): 108–114, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1210
The relationships between intangible organizational elements and organizational performance
Authors: Carmeli Abraham , Tishler Ashler
Published: October 2004

Despite the growing awareness of the importance of researching core strategic resources and activities, the work that has been done to date has largely taken the form of anecdotal reports and case study analysis. We have yet to see large‐sample studies demonstrating how organizational elements, independently, complementarily and interactively, may or may not enhance the organization's performance. Moreover, little attention has been given to researching this topic in public sector organizations. The present study aims to bridge this gap by examining the impact of a set of independent intangible organizational elements and the interactions among them on a set of objective organizational performance measures in a sample of local government authorities in Israel. The results of a multivariate analysis indicate that organizational performance (measured by self‐income ratio, collecting efficiency ratio, employment rate, and municipal development) can be well explained by six intangible organizational elements (managerial capabilities, human capital, internal auditing, labor relations, organizational culture, and perceived organizational reputation) and the interactions among them, which need to be taken into account in any cost effective development. Copyright © 2004 John Wiley & Sons, Ltd.
Learning Through Inquiry: An Overview of Undergraduate Research
Authors: Kinkead Joyce
Published: October 2004

Undergraduate researchers are involved in learning, and universities can structure programs to support them in a number of ways.
The Boyer Commission Report and its Impact on Undergraduate Research
Authors: Katkin Wendy
Published: October 2004

Spurred by the Boyer Report, research universities have made considerable progress in raising the status of undergraduate education and transforming it in ways that bring inquiry to the fore.
Undergraduate Research at the Research Universities
Authors: Ash Merkel Carolyn
Published: October 2004

Snapshots of undergraduate research programs at research universities offer models and ideas as benchmark programs.
Undergraduate research at two‐year colleges
Authors: Perez Jorge A.
Published: October 2004

Although undergraduate research may not be considered typical of the community college mission, many two‐year colleges have embraced it for hands‐on learning and community action projects.
Interdisciplinary research: The NCUR‐Lancy awards
Authors: Lancy David F.
Published: October 2004

A program was designed to promote interdisciplinary research by undergraduates during the summer. Lessons learned from the first four years of this initiative are described.
What one faculty member does to promote undergraduate research
Authors: Lancy David F.
Published: October 2004

An anthropologist reflects on his efforts to involve undergraduates in research and creative endeavors. He concludes with a set of questions that focus the reader's attention on creating undergraduate opportunities in research.
Cysteine and keto acids modulate mosquito kynurenine aminotransferase catalyzed kynurenic acid production
Authors: Han Qian , Li Jianyong
Published: October 2004

Kynurenine aminotransferase (KAT) catalyzes the formation of kynurenic acid (KYNA), the natural antagonist of ionotropic glutamate receptors. This study tests potential substrates and assesses the effects of amino acids and keto acids on the activity of mosquito KAT. Various keto acids, when simultaneously present in the same reaction mixture, display a combined effect on KAT catalyzed KYNA production. Moreover, methionine and glutamine show inhibitory effects on KAT activity, while cysteine functions as either an antagonist or an inhibitor depending on the concentration. Therefore, the overall level of keto acids and cysteine might modulate the KYNA synthesis. Results from this study will be useful in the study of KAT regulation in other animals.
The power of vanadate in crystallographic investigations of phosphoryl transfer enzymes
Authors: Davies Douglas R. , Hol Wim G.J.
Published: October 2004

The formation of transition state mimics of phosphoryl transfer reactions with the metal oxoanion vanadate is a powerful technique in macromolecular crystallography. The tendency of vanadate to form pentacovalent complexes exhibiting trigonal bipyramidal geometry makes this compound a close approximation of the transition state for such reactions. In many cases, vanadate complexes provide the most accurate visualization of the transition state that can be reasonably achieved. A survey of the Protein Data Bank reveals that a relatively small number of structures (39, representing 23 unique proteins) include vanadate, yet these structures represent four of the six E.C. categories of enzymes, and were obtained in crystals with pH values ranging from 5.0 to 7.8. Vanadate has additional advantages over other compounds such as aluminum fluoride, beryllium fluoride and nitrate used for visualization of transition state mimics in that vanadate readily forms covalent bonds with a variety of ligands and has produced a wider variety of transition state mimics. Given the hundreds of crystal structures that have been solved for phosphoryl transfer enzymes, it is surprising that vanadate has not been used more frequently for visualization of transition state analogs. We propose that an opportunity exists for vanadate to become a more commonly utilized component of the macromolecular crystallographer's toolbox.
Interaction of calmodulin with the phosphofructokinase target sequence
Authors: Martin Stephen R. , Biekofsky Rodolfo R. , Skinner Murray A. , Guerrini Remo , Salvadori Severo , Feeney James , Bayley Peter M.
Published: October 2004

Ca4
· calmodulin (Ca4
· CaM) inhibits the glycolytic enzyme phosphofructokinase, by preventing formation of its active tetramer. Fluorescence titrations show that the affinity of complex formation of Ca4
· CaM with the key 21‐residue target peptide increases 1000‐fold from pH 9.0 to 4.8, suggesting the involvement of histidine and carboxylic acid residues. 1H NMR pH titration indicates a marked increase in pK
a of the peptide histidine on complex formation and HSQC spectra show related pH‐dependent changes in the conformation of the complex. This unusually strong sensitivity of a CaM–target complex to pH suggests a potential functional role for Ca4
· CaM in regulation of the glycolytic pathway.
Sphingosine 1‐phosphate transactivates c‐Met as well as epidermal growth factor receptor (EGFR) in human gastric cancer cells
Authors: Shida Dai , Kitayama Joji , Yamaguchi Hironori , Yamashita Hiroharu , Mori Ken , Watanabe Toshiaki , Yatomi Yutaka , Nagawa Hirokazu
Published: October 2004

Receptor tyrosine kinases (RTKs) are transactivated by the stimulation of G protein‐coupled receptors (GPCRs). Sphingosine 1‐phosphate (S1P), a ligand of GPCR, is known as a tumor‐promoting lipid, but its signaling pathways are not fully understood. We here demonstrated that S1P induces rapid and transient tyrosine phosphorylation of epidermal growth factor receptor (EGFR) and c‐Met in gastric cancer cells, both of which have been proposed as prognostic markers of gastric cancers. The pathway of S1P‐induced c‐Met transactivation is Gi‐independent and matrix metalloproteinase‐independent, which differs from that of EGFR transactivation. Our results indicate that S1P acts upstream of various RTKs and thus may act as a potent stimulator of gastric cancer.
Amino‐terminal domain of ATRIP contributes to intranuclear relocation of the ATR–ATRIP complex following DNA damage
Authors: Itakura Eisuke , Takai Kaori Kajihara , Umeda Kazuyuki , Kimura Makoto , Ohsumi Mariko , Tamai Katsuyuki , Matsuura Akira
Published: October 2004

ATM and rad3‐related protein kinase (ATR), a member of the phosphoinositide kinase‐like protein kinase family, plays a critical role in cellular responses to DNA structural abnormalities in conjunction with its interacting protein, ATRIP. Here, we show that the amino‐terminal portion of ATRIP is relocalized to DNA damage‐induced nuclear foci in an RPA‐dependent manner, despite its lack of ability to associate with ATR. In addition, ATR‐free ATRIP protein can be recruited to the nuclear foci. Our results suggest that the N‐terminal domain of the ATRIP protein contributes to the cell cycle checkpoint by regulating the intranuclear localization of ATR.
Reduced adipose tissue mass and hypoleptinemia in iNOS deficient mice: effect of LPS on plasma leptin and adiponectin concentrations
Authors: Gómez-Ambrosi Javier , Becerril Sara , Oroz Paula , Zabalza Santiago , Rodrı́guez Amaia , Muruzábal Francisco J. , Archanco Marta , Gil Marı́a J. , Burrell Marı́a A. , Frühbeck Gema
Published: October 2004

The aim of this study was to evaluate the impact of the lack of inducible NO synthase (iNOS) on body weight and adipose tissue mass as well as on plasma leptin and adiponectin in basal conditions and 6 h after lipopolysaccharide (LPS) administration in mice. Body weight was not different among male, six‐week‐old wild‐type (WT) and iNOS−/− animals. However, the amount of epididymal white adipose tissue (EWAT) in iNOS−/− mice was significantly reduced (P<0.05). Circulating leptin and leptin mRNA in EWAT were decreased in iNOS−/− mice (P<0.05 and P<0.01, respectively). Plasma adiponectin and adiponectin mRNA were unchanged. LPS administration increased plasma leptin in both genotypes (P<0.05). Neither genotype nor treatment changed plasma adiponectin. In summary, iNOS−/− mice exhibited normal body weight but reduced adipose mass accompanied by hypoleptinemia. Leptin responsiveness to LPS in iNOS−/− mutants is preserved, showing that the LPS‐induced rise in leptin is independent of the presence of functional iNOS. In addition, iNOS deficiency or LPS does not influence expression and circulating levels of adiponectin.
Ycf1‐dependent cadmium detoxification by yeast requires phosphorylation of residues Ser908 and Thr911
Authors: Eraso Pilar , Martı́nez-Burgos Mónica , Falcón-Pérez Juan M. , Portillo Francisco , Mazón Marı́a J.
Published: October 2004

Yeast cadmium factor (Ycf1), an ATP‐binding cassette (ABC) protein of the multidrug resistance protein subfamily, is a vacuolar GS‐conjugate transporter required for heavy metal and drug detoxification. There is evidence that phosphorylation may play a critical role in the function of ABC transporters from higher organisms. In this work, the possibility of Ycf1 phosphorylation was examined using site‐directed mutagenesis. We demonstrate that Ser908 and Thr911, within the regulatory domain (R domain), are functionally important for Ycf1 transport activity and likely sites for phosphorylation. Mutation of these residues to alanine severely impaired the Ycf1‐dependent cadmium detoxification capacity and transport activity, while replacement by acidic residues (mimicking phosphorylation) significantly suppressed the cadmium resistance and transport defects. Both in vitro treatment of Ycf1 with alkaline phosphatase and changes in the electrophoretic mobility of the S908A, T911A and double mutant S908A/T911A proteins supported the conclusion that Ycf1 is a phosphoprotein. The screening of the yeast kinome identified four protein kinases affecting cadmium detoxification, but none of them was involved directly in the phosphorylation of Ycf1. Our data strongly implicate Ycf1 phosphorylation as a key determinant in cadmium resistance in yeast, a significant finding given that very little is known about phosphorylation of ABC transporters in yeast.
Overexpression of transglutaminase 2 accelerates the erythroid differentiation of human chronic myelogenous leukemia K562 cell line through PI3K/Akt signaling pathway
Authors: Kang Sung-Koo , Lee Ji-Young , Chung Tae-Wook , Kim Cheorl-Ho
Published: October 2004

Transglutaminase 2 (TG2) is a GTP‐binding protein with transglutaminase activity. Despite advances in the characterization of TG2 functions and their impact on cellular processes, the role of TG2 in Human chronic myelogenous leukemia K562 cell line is still poorly understood. To understand the biological significance of TG2 during the differentiation of K562 cells, we established and characterized K562 cells that specifically express TG2. Non‐transfected K562 cells showed the increase of membrane‐bound‐TG2 level after 3 days in the response to Hemin and all trans‐retinoic acid (tRA), indicating that membrane recruitment of TG2 is occurred during the erythroid differentiation. However, membrane recruitment of TG2 in TG2‐transfected cells revealed within earlier time period, compared with that in vector‐transfected cells. The ability of membrane‐bound‐TG2 to be photoaffinity‐labeled with [α‐32P]GTP was also increased in TG2‐transfected cells. TG2‐transfected cells activated Akt phosphorylation and inactivated ERK1/2 phosphorylation, compared with vector‐transfected cells. Furthermore, phosphorylation of CREB, one of the Akt substrates, was increased in TG2‐transfected cells and this phenomenon was confirmed by RT‐PCR analysis of several marker genes related with erythroid lineage in the absence of PI3K specific inhibitor, Wortmannin, indicating that PI3K/Akt signaling pathway also involved in the differentiation of the cell. Finally, as results of benzidine positive staining as well as hemoglobinization analysis, overexpression of TG2 revealed acceleration of the erythroid differentiation of K562 cells. Taken together, there was no increased TG2 expression level in the response of Hemin/tRA and delayed differentiation in vector transfected cells than in TG2‐transfected cells, suggesting that suppression of TG2 expression may retard the erythroid differentiation of K562 cells. Therefore, our study may give a new insight for another aspect of the development of this disease.
Estimating and mapping deep drainage risk at the district level in the lower Gwydir and Macquarie valleys, Australia
Authors: Triantafilis J. , Odeh I. O. A. , Jarman A. L. , Short M. G. , Kokkoris E.
Published: October 2004

In the Murray–Darling Basin, irrigated agriculture, which produces rice, dairy, cotton and citrus, is a large consumer of water resources. Effective management of the water resource is therefore important to ensure sustainability of irrigated agriculture. In the lower Gwydir and Macquarie valleys, respectively located in northern and central New South Wales of Australia, extensive irrigated-cotton production is an important contributor to the nation’s export earnings. However, there are problems of excessive deep drainage (DD) in these regions. To address them requires soil and water quality information, but there is little quantitative information to plan for and implement improved water use efficiency. In this paper, we explore methods that could efficiently generate data on natural resources. First, we carried out an electromagnetic induction (EM38) survey to characterise broad soil profile types in the Ashley (lower Gwydir valley) and Trangie (lower Macquarie valley) districts. From the resulting apparent electrical conductivity (ECa, mS/m) data collected using an EM 38 (vertical mode of operation), soil profile sites were selected and sampled, followed by laboratory analysis carried to determine exchangeable cations and clay content. The soil data collected were analysed with a salt and leaching fraction (SaLF) model, based on specific water quality and quantity parameters, such as electrical conductivity of irrigation water (ECiw, dS/m) and rainfall (R, mm/year). Various water application rates (I) were also considered, to simulate irrigated cotton (I = 600 mm/year) and rice production (I = 1200 mm/year) as well as shallow water reservoirs (I = 1800 mm/year). For each irrigation scenario, DD values (mm/year) were estimated. An exponential function was used to describe the relationships between ECa values obtained with the EM38 and estimated DD. These relationships were then used to estimate DD at each of the EM38 survey sites, whereupon cut-off (zc) values were used for indicator transforms of the data. Using indicator kriging (IK) and various irrigation scenarios, we demonstrate the usefulness of this approach in identifying areas of high risk of DD exceeding various cut-off values (zc = 50, 75, 100 and 200 mm/year). Thus, we show where improvements in water-use efficiency could be achieved in the irrigated cotton growing districts of Ashley and Trangie.
Limitations to pasture and sheep enterprises and options for improvement in the Victorian Mallee
Authors: Robertson S. M. , Wimalasuriya R. K.
Published: October 2004

A survey of 29 sheep producers was conducted to benchmark current sheep production practices and producer attitudes to sheep and pasture management in the Victorian Mallee. This report describes the farming systems, defines current sheep management practices and identifies management issues that are limiting production. It also highlights limitations of adoption, suggests potential adoption rates of specific practices by producers, and estimates increases in productivity achievable. Sheep producers could achieve small gains in farm productivity (an estimated average 0.3% annually) by adopting sheep management practices including using superior genetics, reducing ram numbers and introducing supplementary feeding. Possible reasons why recommended practices have not been adopted are discussed. The difficulty of integrating sheep into current short cropping systems was considered to be a key limitation to the adoption of management that could substantially increase productivity, such as higher stocking rates and winter–spring lambing. Important benefits to both productivity and environmental sustainability may be achieved through the replacement of fallowed land with improved pastures. However, a lack of data on the feed base and sheep production in relation to a changing feed base made it impossible to estimate the size of these benefits. It was concluded that further research is needed to collect data and benchmark pasture and livestock enterprises to allow quantification of the potential impact on farm profit of changes to pasture and sheep management in this region.
BeefCheque — a 'dirty boots' approach to achieving profitable beef production in Gippsland
Authors: Howard K. A. , Walsh S. J. , Lamb K. S.
Published: October 2004

The objective of the BeefCheque extension programme is to provide producers with the skills to grow and use more pasture, produce more beef and make more money. A pilot programme operated in Gippsland (in Australia’s South East) from 1995 to 2000 using 15 beef producer groups, each centred on a focus farm, and consisted of monthly farm walks and other ‘dirty boots’ activities. Each BeefCheque group progressed through a series of activities planned by the group and their facilitator. A total of 420 producers participated, with 250 producers participating at any one point in time (9% of Gippsland beef producers and 19% of cattle produced in Gippsland). Project success was evaluated using Bennett’s hierarchy as a framework. In a survey at the end of the first 5 years, 94% of respondents had tried one or more new grazing management practices, and 54% had tried at least 11 new grazing management practices. This had increased from 2 years previously when the median number of practices learnt was 9 or more. An analysis of a small percentage of farms involved in benchmarking over 4 years (10–21% of producers involved in BeefCheque) showed significant increases in total liveweight output (kg/ha), saleyard price ($/kg beef liveweight), gross farm income ($/ha), net income ($/ha) and farm operating surplus ($/ha). These results matched or exceeded the goals set for the first 5 years and were achieved despite 3 years of exceptionally dry conditions. The success of BeefCheque has been attributed to its use of practical on-farm demonstrations, farm walks and rigorous discussions leading to trialing and use of grazing management practices that increase pasture utilisation and, ultimately, profitability. This led to the overall conclusion that the ‘dirty boots’ activities and approach are important for developing skills and achieving significant change at all levels of farm management.
Comparing copper requirements of canola, albus lupin, durum wheat and spring wheat grown on alkaline soils
Authors: Brennan R. F. , Bolland M. D. A.
Published: October 2004

The copper (Cu) requirements of spring wheat (Triticum aestivum L.), the major crop for alkaline soils in south-western Australia, is well known. The Cu requirements of canola (Brassica napus L.), albus lupin (Lupinus albus L.) and durum wheat (Triticum durum L.), alternative crops for these soils, are not known. A glasshouse experiment, using 2 alkaline soils from south-western Australia, compared the yield and Cu content response to applications of Cu to canola, albus lupin, durum wheat and spring wheat. The Cu was applied either just before 45-days incubation in moist soil at 20°C (incubated Cu), or just before sowing after the incubation treatment (current Cu). Comparative Cu requirements were determined from yields of 45-day-old dried shoots for: (i) Cu already present in the soil (indigenous soil Cu); (ii) the amount of applied Cu required to produce the same percentage of the maximum (relative) yield of dried shoots; and (iii) the Cu content of dried shoots (Cu concentration multiplied by yield of dried shoots). The concentration of Cu in youngest tissue and in dried rest of shoots was used to determine critical Cu concentrations in tissue. Albus lupin used indigenous Cu so effectively it only showed a 10% yield increase to applied Cu. Canola used indigenous Cu more effectively than durum wheat, which was followed by spring wheat. Relative to spring wheat, durum wheat was about 15% less effective at using incubated and current Cu to produce dried shoots and canola was about 47% more effective. Therefore, to produce the same percentage of the maximum (relative) yield as spring wheat, durum wheat required about 15% more incubated and current Cu and canola required about 50% less Cu. As determined using Cu content in shoots, canola and durum wheat were about 45% more effective than spring wheat at increasing Cu content in shoots and albus lupin was about 80% more effective. Evidently, all 3 species took up more copper than spring wheat. Durum wheat did not use this Cu to produce more shoot yield than spring wheat, whereas canola did. The critical Cu concentration in the youngest tissue (mg Cu/kg), associated with 90% of the relative yield, was: 1.5 for spring wheat; 1.7 for durum wheat; 1.0 for albus lupin; and 2.2 for canola. Corresponding values (mg Cu/kg) for rest of dried shoots were: 2.5 for spring wheat; 3.2 for durum wheat; 1.3 for albus lupin; and 2.7 for canola.
Protected canola meal increases milk protein concentration in dairy cows fed a grass silage-based diet
Authors: White C. L. , Staines M. v-H. , Phillips N. , Young P. , Coupar F. , Ashes J. R. , Gulati S. K.
Published: October 2004

Low concentrations of protein in milk occur during the summer–autumn in south-west Australia. This is the period, on dryland farms, when the diet of lactating cows typically consists of grass silage and a mixture of crushed lupins and cereal grain. This experiment was conducted to test the hypothesis that supplying protected canola meal would increase the protein concentration of milk and, possibly, milk yield in cows fed grass silage and a lupin–cereal concentrate.
Sixty Holstein cows in mid lactation were allocated to 2 equal-sized dietary treatment groups: control (lupin) or protected canola meal. The control diet consisted of 14.5 kg DM grass silage (annual ryegrasses–subterranean clover) and 5.4 kg DM of crushed lupins and barley (4:1) per head per day. For the protected canola meal diet, 2.15 kg DM protected canola meal replaced 2.15 kg lupins. The protected canola meal was produced by treating solvent-extracted canola meal with formaldehyde, to produce a product with an in sacco fractional degradability of 0.29 at a rumen fractional outflow rate of 0.08/h. The equivalent degradability of untreated canola meal was 0.80 and of lupin was 0.83.
Cows were individually fed the concentrate ration twice daily, after each milking, then were managed as a single herd in dry lots and fed grass silage. By the end of 8 weeks, cows fed the protected canola meal diet had higher milk protein concentrations (30.7 v. 29.2 g/L; P<0.05) and higher liveweights (604 v. 593 kg; P<0.05). Milk yield (L/day) was increased by 1 L/day, but this effect was not significant (P>0.10). Fat concentration was unaffected by diet (P>0.05). Since the only difference in treatment was the replacement of a portion of lupins with protected canola meal, the results indicate that a deficiency of metabolisable amino acids contributes to the low milk protein concentrations recorded during summer–autumn in south-west Australia. Whether this was acting primarily through a stimulus of appetite, or directly on milk components, could not be determined because silage intakes were not recorded.
Shade performance of a range of turfgrass species improved by trinexapac-ethyl
Authors: Tegg R. S. , Lane P. A.
Published: October 2004

The increased use of enclosed sports stadiums produces shade conditions that seriously affect the quality of turfgrass surfaces, by encouraging undesirable excess vertical succulent growth. Plant growth regulators offer an opportunity to modify a plant’s growth habit, to enable it to be better adapted to a shady environment. To examine growth response to the plant growth regulator, trinexapac-ethyl, cool-season temperate turfgrasses (Kentucky bluegrass–perennial ryegrass, Poa pratensis L./Lolium perenne L.; creeping bentgrass, Agrostis palustris Huds.; supina bluegrass, Poa supina Schrad.; and tall fescue, Festuca arundinacea Schreb.) and a warm-season species (Bermudagrass, Cynodon dactylon L.) were established in a field experiment. Main treatments were 4 levels of shade (0, 26, 56 or 65% shade), with or without trinexapac-ethyl at a rate of 0.5 kg/ha. A pot experiment measured the vertical shoot growth rates of Kentucky bluegrass–perennial ryegrass and tall fescue under 0, 56 or 65% shade, with and without trinexapac-ethyl. Both experiments were conducted under ambient conditions. Light readings taken in full sunlight, at midday through summer and autumn (major period of assessment), ranged from 1350 to 1950 μmol/m2.s. Trinexapac-ethyl reduced vertical growth of all turfgrass species. This resulted in decreased clipping weights and in clipping material having an increased dry matter percentage (i.e. reduced succulence). The impact of trinexapac-ethyl on sward quality and colour was dependent on shade level, for all species. At 56 and 65% shade, quality and colour improvement was maximised with trinexapac-ethyl application; the magnitude of improvement was dependent on species, with Kentucky bluegrass–perennial ryegrass and bentgrass showing the most benefit. It was concluded that trinexapac-ethyl improved the shade performance of a number of turfgrass species commonly used in high quality turf surfaces. It may offer the potential to reduce costs of managing turf in such an environment.
Ammonium thiosulphate as a blossom thinner of 'Delicious' apple, ' Winter Cole' pear and 'Hunter' apricot
Authors: Bound S. A. , Jones K. M.
Published: October 2004

The efficacy of ammonium thiosulphate as a blossom thinner of ‘Delicious’ apple, ‘Winter Cole’ pear and ‘Hunter’ apricot in southern Tasmania was assessed. Ammonium thiosulphate at concentrations of 0.3, 1.5 and 4% (v/v) was applied to both ‘Delicious’ apple and ‘Winter Cole’ pear trees at 20% bloom, 50% bloom or full bloom. At 4%, ammonium thiosulphate proved to be phytotoxic to both crops, resulting in the severe burning of foliage and flowers and also bud death. At 1.5%, ammonium thiosulphate reduced the crop load to an acceptable level without excessive damage. The 0.3% concentration was ineffective regardless of time of application in ‘Delicious’ and at 20% bloom in ‘Winter Cole’. Russet incidence was increased on ‘Delicious’ by the highest concentration applied at 20% bloom. Shoot number increased in some treatments, however there was no effect on return bloom. When ammonium thiosulphate at 2.0% was applied to ‘Hunter’ apricot at 20, 40, 60, 80 or 100% bloom, fruit set was reduced regardless of time of application. Ammonium thiosulphate also improved return bloom of ‘Hunter’ apricot.
Improving tall fescue (Festuca arundinacea) for cool-season vigour
Authors: Reed K. F. M. , Clement S. L. , Feely W. F. , Clark B.
Published: October 2004

A highly winter-active cultivar of tall fescue, Melik, was compared with 3 commercial cultivars in a field experiment in South West Victoria. Winter production of Melik was superior to the widely used commercial cultivars (P<0.05). In a second experiment, a selection from a Melik nursery, designated Melik Select, was compared with the summer-active cultivars, Demeter and AU Triumph. Seed blends of Melik Select and Demeter (1:2 or 2:1 mix) were also evaluated and seasonal production was measured under grazing. Over 3 years, the cumulative yield of tall fescue per se was not different between cultivars, despite a 73% increase in winter for Melik Select compared with Demeter (P<0.001). Melik Select produced 55% of its annual yield in winter. For Demeter the winter proportion was 33%. Spring (P<0.01) and summer production (P<0.001) was superior from the summer-active cultivars, Demeter and AU Triumph, when compared with the yield from Melik Select. Melik Select plots were however, characterised by higher contributions from subterranean clover (Trifolium subterraneum L.). After 7 years of rotational grazing by sheep, the frequency of Melik Select plants (63%) was greater than that of Demeter (9%) and AU Triumph (8%) (P<0.01). Melik Select exhibited greater crown rust (Puccinia coronata) resistance than Demeter and AU Triumph (P<0.001) in autumn.
The seed blend treatments, which included 66% Melik Select, did not increase winter production above that obtained from the summer-active cultivars (P>0.05). It was concluded that, while increased cool season production from tall fescue may be obtained by the use of highly winter-active cultivars sown alone, blends of the contrasting types of tall fescue may provide a more even distribution of growth throughout the year. To significantly increase winter growth in the Hamilton climate, however, the highly winter-active component may have to represent >66% of the blend. Options for using Mediterranean type tall fescue for their autumn–winter growth potential are discussed for districts with a shorter growing season.
Melik Select was compared against 5 check cultivars, in a 3-year field experiment at Hamilton, to characterise the seasonal growth of 36 Neotyphodium endophyte infected accessions of tall fescue collected from the Mediterranean basin. These accessions contained endophyte variants differing from N. coenophialum, as found in continental winter-dormant types of tall fescue. Ratings confirmed the importance of Mediterranean material as a source of vigorous growth during the cool season. Melik Select was superior to other cultivars and accessions in both the cool and warm seasons. The use of Melik Select to develop and evaluate a new type of highly winter-active tall fescue for temperate Australia, since released as cultivar Fraydo, is discussed.
Fraydo tall fescue (Festuca arundinacea L.)
Authors: Reed K. F. M. , Lee C. K. , Jahufer M. Z. Z. , Anderson M. W.
Published: October 2004

Fraydo, a 10-parent synthetic cultivar based on selection from Melik tall fescue is a most productive, highly winter-active cultivar that exhibits little summer activity. Its summer dormancy is associated with persistence over long hot summers. It has an erect growth habit with a long stem and short spike length relative to other cultivars. Maturity, as reflected by date of head emergence, is similar to that for Demeter. Fraydo is well adapted to the environment of south-western Victoria where the original parental selections were made. Fraydo is especially productive in the 7–8 month growing season/550–700 mm annual rainfall districts. Evidence is emerging that it is highly palatable to sheep and well adapted to a wide range of environments in temperate Australia.
Effective trapping methods for assessing invertebrates in vineyards
Authors: Thomson L. J. , Neville P. J. , Hoffmann A. A.
Published: October 2004

There is increasing interest in developing environmental management systems to ensure that agricultural industries are sustainable; invertebrate indicators provide one potential tool for monitoring sustainable production. As a first step in developing invertebrate indicators for viticulture, we compare the efficiency of 3 common trapping methods in assessing populations of relevant orders of invertebrates. Yellow sticky traps were more effective in trapping Hymenoptera, Thysanoptera, Hemiptera, Diptera, Araneae and Coleoptera; transparent sticky traps were best for Lepidoptera and Neuroptera; and pitfall traps for Collembola and the family Formicidae. Numbers collected differed among months and December was the best month, overall, for trapping. Preliminary guidelines are developed for assessing key orders. While several methods are required for assessing invertebrate biodiversity, most orders can be sampled with a single method, particularly the yellow sticky trap. Our results indicate that changes in numbers of beneficial orders, due to changes in management practices, can be detected. Power analyses suggest a relatively small number of yellow sticky traps would be sufficient to detect changes of around 30%, or greater.
Nanoscale Morphology of Conjugated Polymer/Fullerene‐Based Bulk‐ Heterojunction Solar Cells
Authors: Hoppe H. , Niggemann M. , Winder C. , Kraut J. , Hiesgen R. , Hinsch A. , Meissner D. , Sariciftci N. S.
Published: October 2004

The relation between the nanoscale morphology and associated device properties in conjugated polymer/fullerene bulk‐heterojunction “plastic solar cells” is investigated. We perform complementary measurements on solid‐state blends of poly[2‐methoxy‐5‐(3,7‐dimethyloctyloxy)]‐1,4‐phenylenevinylene (MDMO‐PPV) and the soluble fullerene C60derivative 1‐(3‐methoxycarbonyl) propyl‐1‐phenyl [6,6]C61(PCBM), spin‐cast from either toluene or chlorobenzene solutions. The characterization of the nanomorphology is carried out via scanning electron microscopy (SEM) and atomic force microscopy (AFM), while solar‐cell devices were characterized by means of current–voltage (I–V) and spectral photocurrent measurements. In addition, the morphology is manipulated via annealing, to increase the extent of phase separation in the thin‐film blends and to identify the distribution of materials. Photoluminescence measurements confirm the demixing of the materials under thermal treatment. Furthermore the photoluminescence of PCBM clusters with sizes of up to a few hundred nanometers indicates a photocurrent loss in films of the coarser phase‐separated blends cast from toluene. For toluene‐cast films the scale of phase separation depends strongly on the ratio of MDMO‐PPV to PCBM, as well as on the total concentration of the casting solution. Finally we observe small beads of 20–30 nm diameter, attributed to MDMO‐PPV, in blend films cast from both toluene and chlorobenzene.
Charge Storage Capability in Nanoarchitectures of V2O5/Chitosan/Poly(ethylene oxide) Produced Using the Layer‐by‐Layer Technique
Authors: Huguenin F. , dos Santos D. S. , Bassi A. , Nart F. C. , Oliveira O. N.
Published: October 2004

The electrochemical and electrochromic properties of layer‐by‐layer nanoarchitectures of V2O5/chitosan and V2O5 alternated with a blend of poly(ethylene oxide) (PEO) and chitosan have been examined. Using a blend was important, since multilayers of PEO/V2O5 could not be built. The number of electrochemically active V2O5 sites was estimated to be around 3.4 × 10–8 mol cm–2 and 4.4 × 10–8 mol cm–2 for V2O5/chitosan and V2O5/blend, respectively, based on the UV‐vis absorbance attributed to the intervalence V4+→V5+ transfer. A pronounced effect from PEO was observed in the migration/diffusion process, according to cyclic voltammetry and impedance spectroscopy data. The charges injected were 3.29 mC cm–2 and 8.02 mC cm–2 for V2O5/chitosan and V2O5/blend, respectively, at 20 mV s–1. For V2O5/blend, the chronopotentiometric curves show that x in LixV2O5 is about 1.77. Evidence of enhanced ionic transport was provided by the Fourier transform infrared (FTIR) spectrum, which indicated lithium complexation by PEO and formation of a larger amorphous phase of PEO within the V2O5 matrix. The importance of these results for the production of Li secondary microbatteries and electrochromic devices is discussed.
Pyridylamino‐β‐cyclodextrin as a Molecular Chaperone for Lipopolysaccharide Embedded in a Multilayered Polyelectrolyte Architecture
Authors: Jessel N. B. , Schwinté P. , Donohue R. , Lavalle P. , Boulmedais F. , Darcy R. , Szalontai B. , Voegel J.‐C. , Ogier J.
Published: October 2004

Layer‐by‐layer self‐assembled polyelectrolyte films containing a charged cyclodextrin and lipopolysaccharide (LPS) are developed for the first time as a potential model for local endotoxin antagonist delivery. We have examined the biological activity of a lipopolysaccharide from E. coli incorporated into multilayered architectures made of poly‐(L‐lysine) and poly‐(L‐glutamic acid). Used in such build‐ups, a polycationic cyclodextrin, heptakis(6‐deoxy‐6‐pyridylamino)‐β‐cyclodextrin showed molecular chaperone properties by enabling restoration of the LPS biological activity whenever lost upon interaction with poly‐(L‐lysine).
Effects of Crystallinity in Spin‐On Pure‐Silica‐Zeolite MFI Low‐Dielectric‐Constant Films
Authors: Li Z. J. , Li S. , Luo H. M. , Yan Y. S.
Published: October 2004

Low‐dielectric‐constant (low‐κ) materials are a critical requirement for future generations of computer microprocessors. As a unique class of porous silicas, pure silica zeolites (PSZs) have been shown to be a promising low‐κ material with excellent mechanical strength (e.g., elastic modulus of 16–18 GPa) due to their crystalline nature. In the present study, we show for the first time that higher crystallinity of spin‐on PSZ MFI films leads to lower κ values and less moisture sensitivity—two critical properties of a porous low‐κ material. We have also advanced the two‐stage synthesis method to produce zeolite nanoparticles with high yield (77 %) and a small diameter (< 80 nm). A κ value of 1.6 is obtained from the silylated highly crystalline PSZ MFI film and the κ value only increases by 12.5 % after exposure to ambient conditions for a period of 24 h.
Singlet and Triplet Exciton Diffusion in a Self‐Organizing Porphyrin Antenna Layer
Authors: Kroeze J. E. , Koehorst R. B. M. , Savenije T. J.
Published: October 2004

We have studied the photoinduced charge separation in a double layer consisting of a 50 nm thick, discotic antenna layer, i.e., free‐base tetra‐para‐octylphenyl porphyrin (H2TOPP), spin‐coated onto a smooth layer of anatase TiO2 using the electrodeless “flash‐photolysis time‐resolved microwave conductivity” technique (FP‐TRMC). This method enables the investigation of the relationship between the morphology of the antenna layer and the exciton diffusion dynamics. Photons absorbed by the porphyrin result in the formation of free mobile electrons in the conduction band of the TiO2. The freshly spin‐coated double layer shows an incident‐photon‐to‐charge‐separation efficiency (IPCSE) of 10 % on excitation at 430 nm. From the amplitude and the temporal shape of the photoconductivity transients we conclude that for the freshly spin‐coated double layer, electron injection occurs both from the singlet and the long‐lived triplet excited state. These triplet states can travel by (Dexter) energy transfer over distances of at least 9.6 nm. After heating the sample above the crystalline–discotic‐lamellar (C–DL) phase‐transition temperature of H2TOPP and subsequent cooling, changes in the optical absorption spectrum are observed, while the IPCSE drops to ca. 1 %. These results are explained in terms of a transition of the morphology of the antenna layer from a predominantly random distribution of the porphyrin molecules just after spin‐coating to a lamellar arrangement upon annealing, consisting of domains of ordered porphyrin stacks. Since the porphyrin macrocycles are perpendicularly oriented with respect to the plane of the lamellae, the center‐to‐center distance between neighboring lamellae disables efficient triplet energy transfer, leaving only the lamella directly adjacent to the TiO2 layer photoactive.
Synthesis and characterization of the novel block copolymer poly(ε‐caprolactone)‐b‐poly(4‐vinyl pyridine) by the combination of coordination and controlled free‐radical polymerizations
Authors: Li Zhongyu , Lu Guangqiang , Huang Junlian
Published: October 2004

A novel block copolymer, poly(ε‐caprolactone)‐b‐poly(4‐vinyl pyridine), was synthesized with a bifunctional initiator strategy. Poly(ε‐caprolactone) prepolymer with a 2,2,6,6‐tetramethylpiperidinyloxy (TEMPO) end group (PCLT) was first obtained by coordination polymerization, which showed a controlled mechanism in the process. By means of ultraviolet spectroscopy and electron spin resonance spectroscopy, the TEMPO moiety was determined to be intact in the polymerization. The copolymers were then obtained by the controlled radical polymerization of 4‐vinyl pyridine in the presence of PCLT. The desired block copolymers were characterized by gel permeation chromatography, Fourier transform infrared spectroscopy, and NMR spectroscopy in detail. Also, the effects of the molecular weight and concentration of PCLT on the copolymerization were investigated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2280–2285, 2004
Is there a functional link between gene interdigitation and multi‐species conservation of synteny blocks?
Authors: MacKenzie Alasdair , Miller Kerry Ann , Collinson Jon Martin
Published: October 2004

It is often overlooked that, in addition to the integrity of protein‐coding sequences (PCSs), human health is crucially linked to the normal expression of genes by cis‐regulatory sequences (CRSs). These CRSs often lie at some considerable distance from the PCSs whose expression they control and often within other genes. The resulting gene interdigitation can make long‐range CRS identification and characterisation difficult. We propose that the need to conserve long‐range CRSs in cis with their target PCSs through evolution, in combination with gene interdigitation and co‐regulation of many genes by individual CRSs, has contributed to the persistence of conserved synteny blocks between diverse species. We further hypothesise that examination of the varying extents of synteny blocks between multiple species in combination with phylogenetic footprinting to find CRSs might provide important clues to the existence of crucial functional CRS–PCS linkages. Identifying CRS–PCS linkages crucial to human health will lead to a better understanding of how their disruption by CRS mutation or chromosome translocation might contribute to many distressing human diseases. BioEssays 26:1217–1224, 2004. © 2004 Wiley Periodicals, Inc.
From modulator to mediator: rapid effects of BDNF on ion channels
Authors: Rose Christine R. , Blum Robert , Kafitz Karl W. , Kovalchuk Yury , Konnerth Arthur
Published: October 2004

Neurotrophins (NTs) are {?AUTHOR} a family of structurally related, secreted proteins that regulate the survival, differentiation and maintenance of function of different populations of peripheral and central neurons.1,2 Among these, BDNF (brain‐derived neurotrophic factor) has drawn considerable interest because both its synthesis and secretion are increased by physiological levels of activity, indicating a unique role of this neurotrophin in coupling neuronal activity to structural and functional properties of neuronal circuits. In addition to its classical neurotrophic effects, which are evident within hours or days and which usually result from changes in cellular gene expression, BDNF exerts acute effects on synaptic transmission and is involved in the induction of long‐term potentiation. Many of these rapid effects of BDNF are mediated by its modulation of ion channel properties following TrkB‐mediated activation of intracellular second messenger cascades and protein phosphorylation. However, recent reports have shown that BDNF not only acts as a modulator of ion channels, but can also directly and rapidly gate a Na+ channel, thereby assigning BDNF the properties of a classical excitatory transmitter. Thus, BDNF, in addition its role as a potent neuromodulator, emerges as an excitatory transmitter‐like substance which acutely controls resting membrane potential, neuronal excitability, synaptic transmission and participates in the induction of synaptic plasticity. BioEssays 26:1185–1194, 2004. © 2004 Wiley Periodicals, Inc.
Floral zygomorphy, the recurring evolution of a successful trait
Authors: Cubas Pilar
Published: October 2004

The flowers of the primitive angiosperm plants were radially symmetrical (actinomorphic). Flowers with bilateral symmetry (zygomorphic) evolved in several clades independently as an adaptation to specialized methods of pollination and played an important role in the diversification of flowering plants. In the model species Antirrhinum majus (snapdragon), the related genes CYCLOIDEA (CYC) and DICHOTOMA (DICH) are key in the development of this trait. This raises the question of whether they played a role in the evolution of floral bilateral symmetry. To address this, the evolution of CYC in relation to the evolution of zygomorphy is being investigated. Phylogenetic and functional analyses of CYC‐like genes are being carried out in groups either closely related to Antirhinum or in families where zygomorphy evolved as an independent event. In addition, the origin of zygomorphy is being studied by comparing the function of CYC‐like genes in species with zygomorphic flowers with their function in species with radially symmetrical flowers. BioEssays 26:1175–1184, 2004. © 2004 Wiley Periodicals, Inc.