bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamical effect of thermal tides in the lower Venus atmosphere
Authors: Takagi M. , Matsuda Y.
Published: July 2006

The thermal tides in the lower atmosphere of Venus are examined. It is shown that both the diurnal and semidiurnal tides excited in the cloud layer propagate to the ground, and the existence of thermal tides below the cloud bottom can be attributed almost to the solar heating in the cloud layer. At altitudes of 0–10 km, the atmospheric superrotation is accelerated and decelerated by the momentum transport associated with the diurnal and semidiurnal tides, respectively. The effect of diurnal tide is much smaller than that of the semidiurnal tide, so that the mean zonal flow is accelerated in the direction opposite to the Venus rotation there. It is argued that this momentum transport by the semidiurnal tide is balanced with the surface friction in the atmospheric layer adjacent to the ground, and the net momentum is supplied from the solid Venus to maintain the atmospheric superrotation.
Validation of rainfall estimates from the TRMM precipitation radar and microwave imager using a radiative transfer model: 1. Comparison of the version‐5 and ‐6 products
Authors: Shige S. , Sasaki H. , Okamoto K. , Iguchi T.
Published: July 2006

The Tropical Rainfall Measuring Mission (TRMM) version‐6 rainfall products show the reduced bias between Precipitation Radar (PR) and TRMM Microwave Imager (TMI) rainfall estimates during the 1997/1998 El Niño event noted in version 5, but need to be verified. We investigate consistency between TMI‐observed brightness temperatures (TBs) at 10 and 19 GHz channels and those simulated from the PR and TMI rainfall estimates using a radiative transfer model. Simulated TBs from PR V6 exhibits better agreement with observed ones than those from PR V5, implying the algorithm improvements. However, discrepancies at 19 GHz suggest that uncertainty in the assumed drop size distribution still remains in PR V6. Simulated TBs from TMI V6 also exhibits better agreement with observed ones than those from TMI V5. However, the simulated 10‐GHz TBs from TMI V6 exhibits more scatter against TMI‐observed ones than those from PR V6 do.
Sensitivity of the NCEP/Noah land surface model to the MODIS green vegetation fraction data set
Authors: Miller Jesse , Barlage Michael , Zeng Xubin , Wei Helin , Mitchell Kenneth , Tarpley Dan
Published: July 2006

Land surface processes are strongly controlled by vegetation cover. Current land surface models represent vegetation as a combination of leaf area index (LAI) and green vegetation fraction (GVF) parameters. The purpose of the study is to examine the impact of a spatially and temporally detailed Moderate Resolution Imaging Spectroradiometer (MODIS)‐based GVF on surface processes in the NCEP Noah land surface model. The largest differences between the GVF data set currently used by the Noah model and the new MODIS GVF data set occur in winter and for tree‐dominated vegetation classes. The greatest impact of the new GVF data on the surface energy and water balance is seen during the summer, when the transpiration is increased by more than 10 W/m2 on average for most vegetation types and the July averaged daily transpiration rate is increased by up to 50 W/m2 for evergreen needleleaf sites.
Three Gorges Dam affects regional precipitation
Authors: Wu Liguang , Zhang Qiang , Jiang Zhihong
Published: July 2006

The impact of the Three Gorges Dam (TGD) on regional precipitation is examined through analysis of the National Aeronautics and Space Administration (NASA) Tropical Rainfall Measuring Mission (TRMM) rainfall rate and Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature and high‐resolution simulation using the Pennsylvania State University‐National Center for Atmospheric Research (PSU‐NCAR) fifth‐generation Mesoscale Model (MM5). The independent satellite data sets and numerical simulation clearly indicate that the land use change associated with the TGD construction has increased the precipitation in the region between Daba and Qinling mountains and reduced the precipitation in the vicinity of the TGD after the TGD water level abruptly rose from 66 to 135 m in June 2003. This study suggests that the climatic effect of the TGD is on the regional scale (∼100 km) rather than on the local scale (∼10 km) as projected in previous studies.
Space Weather and the Sun: Ground‐Based Efforts to Understand Our Star — Early Discoveries
Authors: Kumar Mohi
Published: July 2006

Part 1 of 3
TWEAK binding to the Fn14 cysteine-rich domain depends on charged residues located in both the A1 and D2 modules
Authors: Brown Sharron A. N. , Hanscom Heather N. , Vu Hong , Brew Shelesa A. , Winkles Jeffrey A.
Published: July 2006

TWEAK [TNF (tumour necrosis factor)-like weak inducer of apoptosis] is a member of the TNF superfamily of cytokines. TWEAK binds with high affinity to a single TNF receptor super-family member, Fn14 (fibroblast growth factor-inducible 14). This interaction can stimulate a variety of biological responses, depending on the cell type analysed. The murine Fn14 extracellular region is only 53 amino acids in length and primarily consists of a CRD (cysteine-rich domain) containing three disulphide bonds. In the present study, we investigated whether TWEAK binding to this CRD was dependent on selected evolutionarily conserved amino acid residues by using a site-specific mutagenesis approach and several different ligand-binding assays. Our results indicate that three residues within the predicted Fn14 CRD A1 module (Asp45, Lys48 and Met50) and one residue within the predicted D2 module (Asp62) are each critical for high-affinity TWEAK binding. Mutation of the three charged polar residues Asp45, Lys48 and Asp62 had the greatest deleterious effect, suggesting that electrostatic interactions between TWEAK and Fn14 residues may be particularly important for complex formation or stability. To determine whether the four critical residues were likely to be located on the Fn14 CRD surface, we made an Fn14 homology model based on a previously derived X-ray structure for the B-cell maturation antigen receptor, which also contains only one CRD. This model revealed that each of these critical residues were in areas of the receptor that are potentially capable of interacting with TWEAK. These results indicate that the TWEAK–Fn14 interaction is highly dependent on multiple Fn14 residues located in both CRD modules.
Mutagenesis of solvent-exposed amino acids in Photinus pyralis luciferase improves thermostability and pH-tolerance
Authors: Law G. H. Erica , Gandelman Olga A. , Tisi Laurence C. , Lowe Christopher R. , Murray James A. H.
Published: July 2006

Firefly luciferase catalyses a two-step reaction, using ATP-Mg2+, firefly luciferin and molecular oxygen as substrates, leading to the efficient emission of yellow–green light. We report the identification of novel luciferase mutants which combine improved pH-tolerance and thermostability and that retain the specific activity of the wild-type enzyme. These were identified by the mutagenesis of solvent-exposed non-conserved hydrophobic amino acids to hydrophilic residues in Photinus pyralis firefly luciferase followed by in vivo activity screening. Mutants F14R, L35Q, V182K, I232K and F465R were found to be the preferred substitutions at the respective positions. The effects of these amino acid replacements are additive, since combination of the five substitutions produced an enzyme with greatly improved pH-tolerance and stability up to 45 °C. All mutants, including the mutant with all five substitutions, showed neither a decrease in specific activity relative to the recombinant wild-type enzyme, nor any substantial differences in kinetic constants. It is envisaged that the combined mutant will be superior to wild-type luciferase for many in vitro and in vivo applications.
Dihydroceramide:sphinganine C-4-hydroxylation requires Des2 hydroxylase and the membrane form of cytochrome b5
Authors: Enomoto Ayako , Omae Fumio , Miyazaki Masao , Kozutsumi Yasunori , Yubisui Toshitsugu , Suzuki Akemi
Published: July 2006

Des2 (degenerative spermatocyte 2) is a bifunctional enzyme that produces phytoceramide and ceramide from dihydroceramide. The molecular mechanism involved in C-4-hydroxylation has not been studied in detail. In the present paper, we report that C-4-hydroxylation requires an electron-transfer system that includes cytochrome b5 and that the hydroxylase activity is reconstituted in an in vitro assay with purified recombinant Des2. FLAG-tagged mouse Des2 was expressed in insect Sf9 cells and was purified by solubilization with digitonin and anti-FLAG antibody affinity column chromatography. The activity of dihydroceramide:sphinganine C-4-hydroxylase was reconstituted with the purified FLAG–Des2, mb5 (the membrane form of cytochrome b5) and bovine erythrocyte membrane. The apparent Km and Vmax of Des2 for the substrate N-octanoylsphinganine were 35 μM and 40 nmol·h−1·mg of protein−1 respectively. The Km of the hydroxylase for mb5 was 0.8 μM. Interestingly, mb5 was not replaced with the soluble form of cytochrome b5, which lacks the C-terminal membrane-spanning domain. The erythrocyte membrane was separated into Triton X-100-soluble and -insoluble fractions, and the detergent-soluble fraction was replaced by the soluble or membrane form of b5R (NADH-cytochrome b5 reductase). The Triton-X-100-insoluble fraction contained trypsin-resistant factors. The Des2 protein is found in the endoplasmic reticulum and is assumed to have three membrane-spanning domains. The findings of the present study indicate that the hydroxylation requires complex formation between Des2 and mb5 via their membrane-spanning domains and electron transfer from NADH to the substrate via the reduction of mb5 by b5R.
The structure of SENP1–SUMO-2 complex suggests a structural basis for discrimination between SUMO paralogues during processing
Authors: Shen Lin Nan , Dong Changjiang , Liu Huanting , Naismith James H. , Hay Ronald T.
Published: July 2006

The SUMO (small ubiquitin-like modifier)-specific protease SENP1 (sentrin-specific protease 1) can process the three forms of SUMO to their mature forms and deconjugate SUMO from modified substrates. It has been demonstrated previously that SENP1 processed SUMO-1 more efficiently than SUMO-2, but displayed little difference in its ability to deconjugate the different SUMO paralogues from modified substrates. To determine the basis for this substrate specificity, we have determined the crystal structure of SENP1 in isolation and in a transition-state complex with SUMO-2. The interface between SUMO-2 and SENP1 has a relatively poor complementarity, and most of the recognition is determined by interaction between the conserved C-terminus of SUMO-2 and the cleft in the protease. Although SENP1 is rather similar in structure to the related protease SENP2, these proteases have different SUMO-processing activities. Electrostatic analysis of SENP1 in the region where the C-terminal peptide, removed during maturation, would project indicates that it is the electrostatic complementarity between this region of SENP1 and the C-terminal peptides of the various SUMO paralogues that mediates selectivity.
Evidence for a dynamic role for homocitrate during nitrogen fixation: the effect of substitution at the α-Lys426 position in MoFe-protein of Azotobacter vinelandii
Authors: Durrant Marcus C. , Francis Amanda , Lowe David J. , Newton William E. , Fisher Karl
Published: July 2006

Although it is generally accepted that the active site of nitrogenase is located on the FeMo-cofactor, the exact site(s) of N2 binding and reduction remain the subject of continuing debate, with both molybdenum and iron atoms being suggested as key players. The current consensus favours binding of acetylene and some other non-biologically relevant substrates to the central iron atoms of the FeMo-cofactor [Dos Santos, Igarashi, Lee, Hoffman, Seefeldt and Dean (2005) Acc. Chem. Res. 38, 208–214]. The reduction of N2 is, however, a more demanding process than reduction of these alternative substrates because it has a much higher activation energy and does not bind until three electrons have been accumulated on the enzyme. The possible conversion of bidentate into monodentate homocitrate on this three electron-reduced species has been proposed to free up a binding site for N2 on the molybdenum atom. One of the features of this hypothesis is that α-Lys426 facilitates chelate ring opening and subsequent orientation of the monodentate homocitrate by forming a specific hydrogen bond to the homocitrate -CH2CH2CO2− carboxylate group. In support of this concept, we show that mutation of α-Lys426 can selectively perturb N2 reduction without affecting acetylene reduction. We interpret our experimental observations in the light of a detailed molecular mechanics modelling study of the wild-type and altered MoFe-nitrogenases.
In control of biology: of mice, men and Foxes
Authors: Wijchers Patrick J. E. C. , Burbach J. Peter H. , Smidt Marten P.
Published: July 2006

Forkhead proteins comprise a highly conserved family of transcription factors, named after the original forkhead gene in Drosophila. To date, over 100 forkhead genes have been identified in a large variety of species, all sharing the evolutionary conserved ‘forkhead’ DNA-binding domain, and the cloning and characterization of forkhead genes have continued in recent years. Forkhead transcription factors regulate the expression of countless genes downstream of important signalling pathways in most, if not all, tissues and cell types. Recent work has provided novel insights into the mechanisms that contribute to their functional diversity, including functional protein domains and interactions of forkheads with other transcription factors. Studies using loss- and gain-of-function models have elucidated the role of forkhead factors in developmental biology and cellular functions such as metabolism, cell division and cell survival. The importance of forkhead transcription factors is underlined by the developmental defects observed in mutant model organisms, and multiple human disorders and cancers which can be attributed to mutations within members of the forkhead gene family. This review provides a comprehensive overview of current knowledge on forkhead transcription factors, from structural organization and regulatory mechanisms to cellular and developmental functions in mice and humans. Finally, we will discuss how novel insights gained from involvement of ‘Foxes’ in the mechanisms underlying human pathology may create new opportunities for treatment strategies.
Demonstration of an Fe doped KNbO3 photorefractive hybrid
Authors: Deer M. J.
Published: July 2006

Highly birefringent liquid crystals are attractive for photorefractive applications but device operation, usually restricted to the Raman-Nath regime, can be degraded by small phase shifts between the optical and refractive index gratings and coarse grating spacings with narrow beam intersection angles. Having to apply external electric fields and tilt the cell at an angle to the grating k vector cause further complications. In this letter, two-beam coupling in a hybrid photorefractive cell comprising a nematic liquid crystal layer influenced by an Fe doped KNbO3 window is described. The KNbO3 window determines photorefractive properties while the liquid crystal amplifies the overall refractive index modulation. Full Bragg matched gain and large beam intersection angles, with perfect 90° phase shifts between the optical and refractive index gratings, at normal incidence, without the need for an external field are demonstrated.
High efficiency polarization-sensitive organic photovoltaic devices
Authors: Tanaka Hideyuki , Yasuda Takeshi , Fujita Katsuhiko , Tsutsui Tetsuo
Published: July 2006

We report the fabrication of polarization-sensitive photovoltaic devices made of heterojunction-type vacuum-sublimed multilayer films composed of aligned 3,4,9,10-perylenetetracarboxylic-bis-benzimidazole (aligned PTCBI) and titanyl phthalocyanine (TiOPc). The PTCBI layer was made to be well aligned without losing high power conversion efficiency. The device configuration was ITO/In/aligned PTCBI/TiOPc/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/Au, and the thickness of each layer was optimized for polarization-sensitive photodetection. The power conversion efficiencies under polarized white light parallel and perpendicular to the molecular orientation axis were 0.78% and 0.45%, respectively. When monochromatic polarized light at 540nm was used, the photocurrent ratio of the parallel to the perpendicular condition reached a maximum of 2.32.
Application of tomographic imaging to photodiode arrays in large helical device
Authors: Liu Y. , Tamura N. , Peterson B. J. , Iwama N. , Group LHD Experimental
Published: July 2006

Two 20-channel absolute x-ray ultraviolet photodiode (AXUVD) cameras are being used on the large helical device for measuring the two-dimensional radiation distribution. The local radiation emissivity is obtained by inverting the measured brightnesses with linear (Tikhonov-Phillips) or nonlinear (maximum entropy) regularization methods. The most important features of these improved methods are the capability of reconstructing radiation distributions without any symmetry assumptions, built-in smoothing, and useful reconstructions with relatively few detector channels. Together with improvements in the analysis method, the current AXUVD system makes it possible to obtain radiation emissivity images of various localized radiative phenomena, such as radiation collapse or transport of impurities injected into the plasma.
Developments in Using Scanning Probe Microscopy To Study Molecules on Surfaces — From Thin Films and Single-Molecule Conductivity to Drug–Living Cell Interactions
Authors: Thordarson Pall , Atkin Rob , Kalle Wouter H. J. , Warr Gregory G. , Braet Filip
Published: July 2006

Scanning probe microscopy (SPM) techniques, including atomic force microscopy (AFM) and scanning tunnelling microscopy (STM), have revolutionized our understanding of molecule–surface interactions. The high resolution and versatility of SPM techniques have helped elucidate the morphology of adsorbed surfactant layers, facilitated the study of electronically conductive single molecules and biomolecules connected to metal substrates, and allowed direct observation of real-time processes such as in situ DNA hybridization and drug–cell interactions. These examples illustrate the power that SPM possesses to study (bio)molecules on surfaces and will be discussed in depth in this review.
Microstructures in Lubricant Thin Layers at the Magnetic Disk Surface, Observed Using Cryogenic Atomic Force Microscopy
Authors: Kato Teiji , Nakakawaji Takayuki
Published: July 2006

Cryogenic Atomic Force Microscopy (AFM) was used to observe perfluoropolyether (PFPE) lubricant molecules at atomically flat solid surfaces and at a magnetic disk surface to understand the lubricity of ultra-thin (1 nm) lubricant layers at the hard disk surface. Molecular imaging of PFPE lubricant molecules reveals the formation of reversed micelle structures at comparatively non-polar solid surfaces such as gold or the carbon overcoat of magnetic disks.
Determination of the Complete Absolute Configuration of Petriellin A
Authors: Aurelio Luigi , Brownlee Robert T. C. , Dang Jason , Hughes Andrew B. , Polya Gideon M.
Published: July 2006

We report the full structural determination of the depsipeptide petriellin A. The absolute configuration of the amino acid residues, N-methyl isoleucine and N-methyl threonine, have been determined by a combination of HPLC and TLC comparison of synthetic Marfey’s derivatives and Marfey’s derivatives of the natural product hydrolysate. The configuration of the chiral centres in these two N-methylated residues was found to be the same as those of the common unmethylated l-amino acids.
Friction Measurement Between Polyester Fibres Using the Fibre Probe SPM
Authors: Mizuno Hiroyasu , Kjellin Mikael , Nordgren Niklas , Pettersson Torbjörn , Wallqvist Viveca , Fielden Matthew , Rutland Mark W.
Published: July 2006

An SPM has been used to measure frictional interactions between two crossed fibres for the first time. The preparation of the surfaces is briefly described, but the crucial element is that the fibre attached to the AFM cantilever is glued parallel to the long axis.
The fibres consist of polyester and frictional forces were measured both in air and solutions of cationic surfactant C14TAB. The friction coefficients reduce markedly with increasing concentration of surfactant which is ascribed to the formation of a boundary lubricating film between the surfaces. On removal of the solution, the subsequent friction coefficient in air was reduced by more than a factor of two compared to its value before immersion.
Crop stubbles are as important for sheep production as annual pastures in the Victorian Mallee
Authors: Robertson S. M.
Published: July 2006

The impact of different management strategies on production and profit can be evaluated with knowledge of how sheep production responds to changes in the available feed base and sheep or pasture management. This study aimed to quantify on-farm pasture and sheep production in mixed sheep and cropping systems in the Victorian Mallee of south-eastern Australia (325 ± 50 mm annual rainfall) as a prelude to computer simulation modelling. During 2001 (average rainfall) and 2002 (extreme drought) pasture production, the feed base and sheep production were monitored in 15 paddocks on 5 properties located across the region. Crop stubbles were the major source of feed for 6 months of the year, enabling ewes to maintain liveweight. There was more variation in pasture parameters between paddocks at the 1 location than between locations. The botanical composition, plant density, soil fertility and management were key variables associated with between-paddock variation in pasture production. Variation in pasture production between years was larger than within-year differences. In contrast, stocking rates were not much lower in the drought year of 2002 than in 2001. This study suggests there is potential for management to improve pasture production, and demonstrates the importance of feed sources other than annual pasture for sheep production in environments where the annual pasture growing season is short.
Nutritive characteristics of annual species in irrigated pasture in northern Victoria
Authors: Heard J. W. , Francis S. A. , Doyle P. T.
Published: July 2006

We examined changes in estimated metabolisable energy (ME), crude protein (CP) and neutral detergent fibre (NDF) concentrations of irrigated annual pastures through winter and spring in 2002. The types of pastures sampled were ‘high’ subterranean clover (HS, at least 800 g/kg DM clover), ‘low’ subterranean clover (LS, about 400 g/kg DM clover) and ‘low’ Persian clover (LP, about 500 g/kg DM clover). Estimates were also made of selection differentials, namely the nutrient concentration in the pasture fraction likely to be consumed expressed as a proportion of the nutrient concentration in the whole sward to ground level. The ME concentrations in all pasture types increased from May to August, after which concentrations in LS and LP declined, while the ME concentrations in HS declined after September. Low Persian pasture was significantly (P<0.001) higher in ME than the subterranean clover pastures except in September. There was a significant quadratic relationship between ME and time in months and this relationship differed significantly between the 3 pasture treatments. There was a significant (P<0.001) linear decline in CP concentration through the sampling period. The rate of decline in CP concentration was greatest for HS and lowest for LP pastures. Neutral detergent fibre concentrations declined gradually until August and then increased in all pastures. High subterranean clover pastures were lower (P<0.05) than LS pastures in all months. Low Persian clover pastures were higher in NDF than HS pastures, but lower than LS pastures in most months.There were small but significant differences in selection differentials for estimated ME between months when pastures were cut to 4 cm. Selection differentials for ME were between 1.01 and 1.13 across pasture types. Crude protein selection differentials were higher than for ME and varied between 1.11 and 1.46. There were small significant differences in selection differentials between months for NDF (0.74–0.96). Calculated selection differentials at different cut heights indicated that a nutrient gradient existed throughout the annual pasture sward. Pastures cut at high (>8 cm) cut heights had higher ME and CP and lower NDF, than pastures cut to 4 cm. Differences in selection differentials at different cut heights were apparent between pasture types.
Phosphorus, copper and zinc requirements of no-till wheat crops and methods of collecting soil samples for soil testing
Authors: Bolland M. D. A. , Brennan R. F.
Published: July 2006

Plant testing of wheat crops in south-western Australia, sown using no-till for >7 years, often indicates marginal to deficient levels of the soil immobile elements phosphorus (P), copper (Cu) and zinc (Zn). In this region, P, Cu and Zn fertilisers are usually placed (drilled) with the seed while sowing crops. However, in no-till cropping, because the fertilisers are placed in the same rows as the seed during sowing, in the years after application the 3 elements are no longer mixed through the top 10 cm of soil. It may be more effective to deep band fertiliser below seed while sowing no-till crops. Alternatively, cultivating the top 10 cm of soil every 5–7 years would mix previously applied fertiliser P, Cu and Zn through the topsoil, which should improve the effectiveness of the fertiliser residues for the current and subsequent no-till crops. In field experiments in paddocks in south-western Australia sown using no-till for 7–11 years, we compared these 2 alternative methods to the standard no-till practice of drilling fertiliser with the seed in the same crop rows. No shoot or grain yield responses of wheat were obtained. The exception was that in 1 experiment cultivating the topsoil before drilling P with seed was more effective than drilling or deep banding P. Concentrations of P, Cu and Zn measured in wheat shoots or grain were either unaffected by treatment, or, compared with drilling fertiliser with seed, were larger for the other 2 methods, indicating these 2 methods were more effective at increasing the concentrations of the elements in plant parts. The 3 elements have been shown to have good residual values for crop production in the region. Therefore, we recommend that experiments should not be performed in existing no-till paddocks until the residual value of P, Cu and Zn applied in the old cropping system has become negligible, which could, for Cu and Zn in particular, take many years.
In the second year, the experiments were used to compare 4 different ways of collecting soil samples from the top 10 cm of soil (standard soil sampling depth used in south-western Australia) to measure soil test P (Colwell), Cu (ammonium oxalate) and Zn (DTPA). The samples were either collected randomly within the plots (present method), always in the rows used to sow seed and apply fertiliser, always between the rows, or half in and half between the rows. Soil test values for P, Cu and Zn were unaffected by amount of element applied and method of application when samples were collected between rows, at random, or from all banded treatments where fertiliser was placed below the 0–10 cm sampling depth. Soil test values for samples collected in rows increased as the amount of fertiliser applied increased and were about double the values for samples collected half in and half between rows.
Crop production in the high rainfall zones of southern Australia — potential, constraints and opportunities
Authors: Zhang H. , Turner N. C. , Poole M. L. , Simpson N.
Published: July 2006

Annual cropping has been expanding in the high rainfall zone of southern Australia. The higher rainfall and longer growing season compared with the traditional wheatbelt contribute to a much higher yield potential for major crops. Potential yields range from 5 to 8 t/ha for wheat and 3 to 5 t/ha for canola, although current crop yields are only about 50% of those potentials. The large yield gap between current and potential yields suggests that there is an opportunity to lift current yields. Both genetic constraints and subsoil constraints such as waterlogging, soil acidity, sodicity, and high soil strength contribute to the low yields. Waterlogging is a widespread hidden constraint to crop production in the region. Controlling waterlogging using a combination of raised beds and surface or subsurface drains is the first step to raise the productivity of the land. Increasing root growth into the subsoil remains a key to accessing more water and nutrients for high yield through early planting, deep ripping, liming and use of primer crops to ameliorate the subsoil. In order to realise the high yield potential, it is essential to achieve higher optimum dry matter at anthesis and high ear number through agronomic management, including early sowing with appropriate cultivars, a high seeding rate and application of adequate nitrogen along with other nutrients. Current cultivars of spring wheat may not fully utilise the available growing season and may have genetic limitations in sink capacity that constrain potential yield. Breeding or identification of long-season milling wheat cultivars that can fully utilise the longer growing season and with the ability to tolerate waterlogging and subsoil acidity, and with disease resistance, will give additional benefits. It is concluded that improving crop production in the high rainfall zone of southern Australia will require attention to overcoming soil constraints, particularly waterlogging, and the development of longer-season cultivars.
Behaviour, Preferences and Cities: Urban Theory and Urban Resurgence
Authors: Storper Michael , Manville Michael
Published: July 2006

The resurgence of big, old cities and their regions is real, but it is merely a part of a broader pattern of urban change in the developed countries, whose broadest tendency is urban emergence, including suburbanisation, and movements of population to certain 'Sunbelt' regions. The problem is that it is difficult to accommodate explanation of both resurgence and emergence using the main explanations in the field today. These include: theories of the knowledge or creative economy, urban amenities, diversity and tolerance, and urban beauty. In most of their common specifications, they do well for either resurgent or emergent cities, but not for both at the same time. This suggests that these ideas, interesting as they are, require much greater specification and, in some cases, overhaul, in order to offer satisfactory responses to the diversity of patterns of urban growth. By examining some of these deficiencies, we conclude that urban theory needs a better understanding of urban choice behaviours and especially the effects of bundling, the limits to preference substitutions and the relationship between past and present preferences, in order to become fully effective in explaining urban resurgence and urban emergence. When these aspects of choice and preference are better integrated into urban theory, then the 'exogenous' causes of urbanisation can be made more endogenous and, in addition, they can be applied better to both emergence and resurgence. Urban research can, by so doing, also potentially become more policy-relevant.
Segregation, Urban Space and the Resurgent City
Authors: Musterd Sako
Published: July 2006

Currently, many major Western cities aim to be attractive to new and economically successful high-tech industries, financial and business services, cultural industries and consumer services industries. Most of these new activities are dependent upon well-skilled creative workers, which will be followed by those who will work in personal services. It is said that a large share of the well-skilled and creative workers requires impulse-rich and attractive urban environments. The idea has arisen that highly segregated, socially and culturally less integrated cities, do not match the newly required city profiles. On the contrary, these cities would exacerbate urban poverty and deter skilled people from settling there. Consequently, some believe that today's cities should also be socially and culturally cohesive. This hypothesis parallels policies against segregation and policy interventions in favour of more mixed and balanced local communities. The latter type of policy is also driven by the idea that more mixed neighbourhoods will enhance individual social opportunities and thus, on aggregate, strengthen the urban economy. This paper elaborates on these ideas and hypotheses and focuses on the rise of new economic activities and the locations they aim for, their potential relation with the social (and ethnic) segregation of the population and the related impact upon the attraction of creative workers and the possible impact on the social mobility of the population. Empirical data from Europe are used to support the arguments.
Substance abuse among medical practitioners
Authors: SERRY NATHAN , BALL J. RICHARD B. , BLOCH SIDNEY
Published: July 2006

This paper reviews the literature relating to the prevalence, causes and treatment of substance abuse and psychiatric illness among doctors. Possible aetiological and pathogenic factors influencing drug‐dependent doctors are discussed and some problems which arise in the management of these doctors are raised. Local studies in relation to certain personality factors in medical students, to cause of death in a medical cohort, and preliminary impressions from a study of substance‐abusing doctors are reported.
Early warning indicators of changes in patterns of drug use in Australia
Authors: PEDIC FADIL , FLAHERTY BRUCE
Published: July 2006

This report examines potential sources for a data system to serve as an ‘early’ warning of changes in drug use in the community. The system would measure changes in drug use to allow the managers of drug and alcohol programmes to adapt their services to meet the changing needs of their clients. The topic was addressed by identifying the ‘dimensions of drug use’ relevant to early warning. Three criteria for inclusion in an early warning network were identified: timeliness, volume of data, and complementarity with other indicators. Each indicator was evaluated against the early warning criteria and dimensions of drug use issues. The result was a list of six indicators which could form an early warning network in Australia: a collection based on general hospital casualty reports, ambulance officer reports of drug overdoses, telephone advice service data, data from key informants, profiles of clients in drug dependence treatment centres and the users of needle exchange centres.
Recreational drug use in New Zealand
Authors: Black Steve , Casswell Sally
Published: July 2006

A general population sample of 5126 New Zealanders aged 15‐45 was surveyed in late 1990 to determine their use of alcohol, tobacco, cannabis, and other illicit drugs. The results show that alcohol and tobacco are the most commonly used drugs. Cannabis had been tried by 43% of the sample, and this level of use appears similar to that in Australia and the United States. Hallucinogens were the next most common illicit drug and had been tried by 8% of the sample. Again the New Zealand rates appear similar to those for the United States or Australia. Much lower levels of use were reported for stimulants, opiates, tranquillizers and solvents than for other illicit drugs. The New Zealand prevalence rates for these substances are lower than those in the United States. The rates for these other classes of drugs are more similar to Australia, but may be slightly lower for stimulants, tranquillizers and solvents.
Alcohol and young people: minimizing the harm
Authors: Saunders Bill , Baily Sally
Published: July 2006

In this paper the literature on patterns of use of alcohol by teenagers is reviewed. The model as proposed by Thorley is used to describe the specific nature of alcohol problems experienced by young people. A systemic approach to prevention is explored and recommendations are made about ways to minimise the harm associated with alcohol use by young people.
Transmitter amino acid neurochemistry in chronic alcoholism with and without cirrhosis of the liver
Authors: Thomas Gregory J. , Dodd Peter R.
Published: July 2006

Neurotransmitter receptor studies are beginning to be applied more widely to human brain tissue obtained at autopsy. By taking tissue from well‐documented cases which have been extensively characterized on histological and morphometric criteria, it is becoming possible to make clinicopathological correlations in studies of the effects of chronic alcohol abuse. Recent findings of alterations in the nature and amounts of amino acid neurotransmitter receptors in alcoholism are summarized, with special emphasis on the effects of chronic severe liver disease. There are selective changes in receptors in the superior frontal cortex of alcoholics. There is a marked increase in the density of the GABA binding site, and a lesser change in the density of the ‘central‐type’ benzodiazepine site, on the GABAA‐benzodiazepine receptor complex. In contrast, glutamate receptors may be much less affected. Together with morphological and cognitive studies, the results suggest that the superior frontal cortex is preferentially damaged in chronic alcoholism. An increase in ‘central‐type’ benzodiazepine sites in both superior frontal cortex and motor cortex in cirrhotic alcoholics may reflect a more global brain damage, as observed in morphological studies. However, it should be noted the changes in [3H]GABA/muscimol binding were less pronounced in cirrhotic alcoholics than in non‐cirrhotic alcoholics.
Alcohol dehydrogenases: gene multiplicity and differential functions of five classes of isozymes
Authors: Holmes Roger
Published: July 2006

Mammalian alcohol dehydrogenases (ADHs) constitute an enzyme family of multiple forms (isozymes) which are differentially distributed throughout the body. Subunit types α, β and γ in dimeric combinations constitute the isozymes of human liver class I ADH, and are >94% homologous in structure. Human π and χ subunits form homodimeric Class II and III ADH isozymes. π‐ADH is liver specific whereas χ‐ADH is widely distributed throughout the body. A sixth human ADH subunit (designated μ or σ), forming a new dimeric human stomach ADH, has been recently reported as Class IV ADH. Evidence for a seventh human ADH subunit has also been described, designated as Class V, the transcripts having been reported in the stomach and liver. All five classes of ADH represent isozymes which are homologous but exhibit at least 30% sequence differences in primary srtructure. Kinetic analyses of four of these classes of ADH indicated differential functions, serving either in the oxidative or reductive mode. Studies from various laboratories indicate the following respective functions: oxidation of aliphatic and aromatic alcohols—liver Class I and Class II, and stomach Class IV ADHs; reduction of peroxidic aldehydes—Classes I, II and IV; ‘biogenic’ alcohol oxidation—Classes I and II; and glutathione‐dependent formaldehyde dehydrogenase‐Class III.
Brief or minimal intervention for ‘alcoholics’? The evidence suggests otherwise
Authors: MATTICK RICHARD P. , JARVIS TRACEY
Published: July 2006

The evidence on the relative impact of intensive intervention(s) and brief advice for alcoholic populations has been interpreted as indicating that there is little advantage for the intensive form of treatment over brief advice. The current review suggests that this conclusion is based on studies with serious and important methodological flaws, and that a slightly different, qualified interpretation is appropriate. There is evidence that intensive intervention does benefit alcohol‐dependent patients, although it seems likely that the less alcohol‐dependent (problem or excessive) drinkers do not require such intense intervention(s). There is also reasonable evidence that at the end of intervening with people with alcohol problems there should be some continued assistance (ie ‘aftercare’) available to extend the intervention, and this assistance should be structured and scheduled. [Mattick P., Jarvis T. Brief or minimal intervention for ‘alcoholics’? The evidence suggests otherwise. Drug Alcohol Rev 1994;13:137–144.]
A summary of the recommendations for smoking cessation interventions: the quality assurance in the treatment of drug dependence project
Authors: MATTICK RICHARD P. , BAILLIE ANDREW , DIGIUSTO EROL , GOURLAY STEVEN , RICHMOND ROBYN , STANTON HARLEY J.
Published: July 2006

This report presents outlines for approaches to smoking cessation. These recommendations are based on a meta‐analysis of the treatment‐outcome literature, a survey of current treatment practices and the views of a panel of experts. Face‐to‐face intervention to assist smokers to stop smoking needs to be considered in the context of a public policy approach to reducing the prevalence of smoking. The nature of face‐to‐face interventions is determined by the time available to practitioners. Where there is no time to intervene (e.g. in some primary health care settings) quality self‐help materials should be prominently displayed. Where there is only 10 minutes or less, attention should be focused on personalizing the health effects of smoking, providing firm advice to quit, providing self‐help material, setting a quit date (if appropriate), identifying social support for cessation and organizing a follow‐up visit. If there is more time to intervene (up to one hour) the previous techniques can be expanded on and supplemented with nicotine replacement and discussion of methods for dealing with high‐risk situations. Longer interventions would use all of these methods, presenting them in more detail, and may also address stress management and minimization of weight gain. [Mattick RP, Baillie A, Digiusto E, Gourlay S, Richmond R, Stanton HJ. A summary of the recommendations for smoking cessation interventions: The quality assurance in the treatment of drug dependence project. Drug Alcohol Rev 1994;13:145–151.]
Results of screening for excessive drinkers in four Sydney teaching hospitals
Authors: BELL ALISON , RICHMOND ROBYN , HEATHER NICK , ROLLNICK STEPHEN
Published: July 2006

In‐patients from selected wards at four Sydney teaching hospitals were screened using a self‐completed general health questionnaire. Screening was carried out between January 1990 and December 1991 as part of a larger study of brief interventions for excessive alcohol consumers detected in the general hospital setting. Comparison with other screening studies of excessive drinkers in hospitals is difficult, due to factors such as the different screening instruments used and the varying population targeted. However, similar trends among excessive drinkers were found, such as age and gender factors. The routine employment of simple screening instruments to detect excessive drinkers among hospital in‐patients is once more urged. [Bell, A, Richmond, R, Heather, N, Rollnick, S. Results of screening for excessive drinkers in four Sydney hospitals. Drug Alcohol Rev 1994;13:179–184.]
The human toxicity of marijuana: a critique of a review by Nahas and Latour
Authors: CHRISTIE MACDONALD J. , CHESHER GREGORY B.
Published: July 2006

A review entitled “The human toxicity of marijuana” was published in 1992 in the Medical Journal of Australia. The authors claimed that the adverse effects of cannabis use have been trivialized and that the effects are much more serious than earlier reported. We have made a careful study of this review and examined the claims made. We compared the claims of the authors with the information contained in the documents they cited and found that at least 28 of the 35 citations in this article were cited inaccurately. Five of these publications were misquoted, or the findings of the study were not fully reported. Twenty‐three citations contained other errors, leaving only six to eight (two citations could not be retrieved because of their obscurity) accurate citations among 35. All of these inaccuracies operate in the direction of finding an adverse effect of marijuana. [Christie M, Chesher GB. The human toxicity of marijuana: a critique of a review by Nahas and Latour. Drug Alcohol Rev 1994;13:209–216.]
Estimated and measured blood alcohol levels in the night‐time driving population
Authors: KLOEDEN CRAIG N. , MOORE VIVIENNE M. , MCLEAN A. JACK
Published: July 2006

The aim of this study was to compare drivers' subjective estimates of their blood alcohol concentration (BAC) with their measured BAC. As part of a night‐time survey of drinking and driving in the Adelaide metropolitan area, 13 951 drivers were approached at intersections between 10 p.m. and 3 a.m. and asked to provide a breath alcohol sample. In addition, drivers were given a reply‐paid mail questionnaire which sought their own estimate of their BAC. The 5765 replies were compared with the measured BACs. It was found that drivers with low measured BACs tended to over‐estimate their BAC while drivers with high BACs tended to under‐estimate; the error in the estimates increased as measured BAC increased. These errors were similar for males and females and did not vary with age group. These results emphasize the need for the wider adoption of reliable means by which people can assess their own BAC more accurately. [Kloeden CN, Moore VM, Mclean AJ. Estimated and measured blood alcohol levels in the night‐time driving population. Drug Alcohol Rev 1994;13:239–245.]
Measuring factors that influence the response of medical practitioners and social workers to problem drinkers: a pilot study
Authors: GORMAN D. M. , JACOBS LYNN M. , McALPINE DONNA
Published: July 2006

It is increasingly recognized that factors such as professionals' empathy, willingness to intervene, self‐efficacy and role legitimacy influence the initial engagement of clients into treatment and the nature of any subsequent therapeutic relationship. These factors are difficult to measure using questionnaires, and for this reason qualitative research techniques are frequently used in this field of inquiry. The present methodological study is based on in‐depth interviews conducted with 16 medical practitioners and 12 social workers, and attempts to overcome one of the main limitations associated with qualitative data—that is, the difficulty of reducing such complex material to a numerical value suitable for quantitative analysis. The interview technique and rating system described were most successful in achieving this in the case of self‐efficacy and least successful in the case of empathy. Possible reasons for this are discussed. It is concluded that the technique described has the potential to elicit detailed data concerning the interactions of medical practitioners and social workers with problem drinkers, and that this material can be reliably rated in a manner that is not unduly time‐consuming and burdensome to researchers. [Gorman DM, Jacobs LM, McAlpine D. Measuring factors that influence the response of medical practitioners and social workers to problem drinkers: a pilot study. Drug Alcohol Rev 1994;13:269–276.]