bluuebunny/crossref_metadata_2025 huggingface dataset:
Families in home care – a resource or a burden? District nurses’ beliefs
Authors: Benzein Eva , Johansson Birgitta , Saveman Britt‐Inger
Published: September 2004

Background.  Caring for families in home care is a growing part of Swedish district nurses’ professional work. District nurses’ facilitative and constraining beliefs about families guide the extent to which families are acknowledged and engaged in the care.

Aims and objectives.  The aim of the study was to explore district nurses’ beliefs about families in home care.

Design.  Explorative, descriptive.

Methods.  Five district nurses participated in focus group interviews on three separate occasions. Each interview lasted approximately 90 minutes, was audio taped and transcribed verbatim. A thematic content analysis was used for analyses of the data.

Results.  The result revealed two underpinning beliefs held by the district nurses towards families in home care: families are a resource and Families are a burden. Families could be a resource for the patient, for the other family members as well as for the district nurses themselves. Families could be a resource for the patient both practically and emotionally by e.g. being present and listening. Being open in communication with other family members and district nurses was also considered as a resource. The district nurses considered families as a burden when they were experienced as demanding in various ways, for example, when family members did not act in a way that pleased the district nurses or when family members showed their suffering.

Conclusions.  This study highlight some facilitating and constraining beliefs held by district nurses: families can be both a resource and a burden.

Relevance to clinical practice.  It is important that district nurses are aware of what beliefs they hold as their beliefs guide their actions towards the families.
Chinese inpatients’ subjective experiences of the helping process as viewed through examination of a nurses' focused, structured therapy group
Authors: Hsiao Fei‐Hsiu , Lin Shu‐Mei , Liao Hsiao‐Yuan , Lai Mei‐Chih
Published: September 2004

Aims and objectives.  This study examined Chinese inpatients’ views on what aspects of a nurses' focused, structured therapy group worked to help their psychological and interpersonal problems and what traditional Chinese cultural values influenced their viewpoints.

Methods.  Nine Chinese inpatients with mental illness participated in the four‐session nurses' focused, structured therapy group. After they completed the last session of therapy, they were invited to participate in a structured interview and a semi‐structured interview regarding their perceptions of the change mechanisms in nurses' focused, structured group therapy. The semi‐structured interviews were recorded and transcribed to be further analysed according to the principal of content analysis.

Results.  The results indicate that (i) all patients believed that a nurses' focused, structured group psychotherapy enhanced their interpersonal learning and improved the quality of their lives, (ii) traditional Chinese cultural values – those emphasizing the importance of maintaining harmonious interpersonal relationships – influenced the Chinese inpatients’ expression of negative emotions in the group and their motivation on interpersonal learning.

Conclusion.  In conclusion, we found that transcultural modification for applying Western group psychotherapy in Chinese culture was needed. The modification included establishing a ‘pseudo‐kin’ or ‘own people’ relationship among group members and the therapists, organizing warm‐up exercises and structured activities, applying projective methods and focusing on the issues of interpersonal relationships and interpersonal problems.

Relevance to clinical practice.  The small sample size of the present study raises questions regarding how representative the views of the sample are with respect to the majority of Chinese inpatients. Nevertheless, this preliminary study revealed a cultural aspect in nursing training that requires significant consideration in order to work effectively with Chinese patients.
Resistance to quinclorac and ALS‐inhibitor herbicides in Galium spurium is conferred by two distinct genes
Authors: Van Eerd L L , McLean M D , Stephenson G R , Hall J C
Published: September 2004

Classical Mendelian experiments were conducted to determine the genetics and inheritance of quinclorac and acetolactate synthase (ALS)‐inhibitor resistance in a biotype of Galium spurium. Plants were screened with the formulated product of either quinclorac or the ALS‐inhibitor, thifensulfuron, at the field dose of 125 or 6 g active ingredient (a.i.) ha−1 respectively. Segregation in the F2 generation indicated that quinclorac resistance was a single, recessive nuclear trait, based on a 1 : 3 segregation ratio [resistant : susceptible (R : S)]. Resistance to ALS inhibitors was due to a single, dominant nuclear trait, segregating in the F2 generation in a 3 : 1 ratio (R : S). The genetic models were confirmed by herbicide screens of F1 and backcrosses between the F1 and the S parent. F2 plants that survived quinclorac treatment set seed and the resulting F3 progeny were screened with either herbicide. Quinclorac‐treated F3 plants segregated in a 1 : 0 ratio (R : S), hence F2 progenitors were homozygous for quinclorac resistance. In contrast, F3 progeny segregated into three ratios: 1 : 0, 3 : 1 and 0 : 1 (R : S) in response to ALS‐inhibitor treatment. This segregation pattern indicates that their F2 parents were either homozygous or heterozygous for ALS‐inhibitor resistance. Therefore, there were clearly two distinct resistance mechanisms encoded by two genes that were not tightly linked as demonstrated by segregation patterns of the F3.
The effect of non‐inversion tillage and light availability on dispersal and spatial growth of Cynodon dactylon
Authors: Guglielmini A C , Satorre E H
Published: September 2004

The invasive ability of Cynodon dactylon is dependent on self dispersal and on cultivation practices. Tillage can seriously change patch biomass and spatial structure, spreading vegetative propagules of the weed. The objectives of this study were: (i) to quantify the effect on non‐inversion tillage on dispersal, establishment and colonization of C. dactylon and (ii) to propose a simple model considering soil cultivation effects and light availability on spatial growth of weed patches. Two experiments were carried out, exploring different soils and environmental conditions. Spatial distribution of vegetative units differed when tillage was conducted with different non‐inversion implements and could be described by simple functions. A minimum patch biomass seems necessary before vegetative structures are vulnerable to movement by cultivation. Only a small proportion of the biomass dispersed from original patches was able to establish. However, simulation showed that the area colonized by C. dactylon mostly increased by means of tillage dispersal, both with and without crop competition, in one growing cycle. It appears sensible to consider changing cultivation practices to reduce weed dispersal and to use crop competition for light to create unsuitable habitats limiting weed colonization.
Secondary dispersal, spatial dynamics and effects of herbicides on reproductive capacity of a recently introduced population of Bromus sterilis in an arable field
Authors: Steinmann H H , Klingebiel L
Published: September 2004

An arable field was subdivided and subjected to either deep inversion ploughing or non‐inversion cultivation after viable seeds of Bromus sterilis had been sown into oilseed rape stubble. After sowing in isolated plots distributed within the field, sequences of cropping treatments for the establishment of two successive winter wheat crops were applied. Each subfield was split into an uphill and a downhill direction for soil cultivation. The field had a 10° slope. In the season following seed introduction, 2.6% of the introduced seeds had successfully germinated and established in the non‐inversion cultivation regime, when no effective graminicide was applied. Ploughing eradicated B. sterilis. Using differential global positioning system (DGPS) mapping of the whole field population, emerged plants were observed up to 8.7 m (uphill treatment) and 21.3 m (downhill treatment) of their initial source. The median distance seeds were transported was 2.3 m uphill and 4.8 m downhill. Post‐emergence application of the herbicide propoxycarbazone slightly reduced weed density and seed weight, and almost halved weed seed production. Application of fenoxaprop‐P‐ethyl was followed by higher density of plants, tillers and seeds of B. sterilis. Seed viability was unaffected by herbicide use. Thus, in the second wheat crop following seed rain, the weed population was dispersed more widely in the field, such that 20–30% of seeds were dispersed more than 5 m distance from the first year's foci of infestation. The relevance of soil cultivation to secondary dispersal of B. sterilis is discussed.
Sorption–desorption of ‘aged’ isoxaflutole and diketonitrile degradate in soil
Authors: Bresnahan G A , Koskinen W C , Dexter A G , Cox L
Published: September 2004

Isoxaflutole is a relatively new herbicide used for weed control in maize. The objective of this research was to increase the understanding of the behaviour and environmental fate of isoxaflutole and its diketonitrile (DKN) degradate in soil, including determination of the strength of sorption to soil and whether sorption is affected by ageing. In sandy loam (SL) and silty clay (SiCl) soils, 14C‐isoxaflutole was found to dissipate rapidly after application to soil; recovery ranged from ∼42% to 68% at week 0, and recovery had decreased to <10% at week 12. Decreases in 14C isoxaflutole residues over time in SL and SiCl soils are consistent with hydrolysis of isoxaflutole and formation of bound DKN residues in the soil. DKN recovery from freshly treated SiCl and SL soils was 41% to 52%. After a 12‐week incubation in SL soil at pH 7.1 and 8.0, recoveries were similar, ∼40%. However, at week 12 in SL soil pH 5.7, DKN recovery decreased to ∼28%. DKN recovery in SiCl soil at week 12 was <10%. Increases in sorption of DKN in SL at pH 5.7 and SiCl soil over time indicate that the DKN degradate is tightly bound to the soil and sorption is affected by soil pH and soil type. Sorption of 14C‐DKN in the SiCl soil more than doubled with ageing compared with the lower Kd sorption coefficient values of the SL soils. In the SiCl soil at time 0, the Kd was 0.6; at 1 week, Kd increased to 2; and at the end of the 12‐week incubation period, Kd was 4.5. This strong binding of DKN to the soil may be due to chelate formation in the interlayer of the clay.
Critical periods for weed control in cotton in Turkey
Authors: Bukun B
Published: September 2004

Field studies were conducted over 4 years in south‐eastern Turkey in 1999–2002 to establish the critical period for weed control (CPWC). This is the period in the crop growth cycle during which weeds must be controlled to prevent unacceptable yield losses. A quantitative series of treatments of both increasing duration of weed interference and of the weed‐free period were applied. The beginning and end of CPWC were based on 5% acceptable yield loss levels which were determined by fitting logistic and Gompertz equations to relative yield data representing increasing duration of weed interference and weed‐free period, estimated as growing degree days (GDD). Total weed dry weight increased with increasing time prior to weed removal. Cotton heights were reduced by prolonged delays in weed removal in all treatments in all 4 years. The beginning of CPWC ranged from 100 to 159 GDD, and the end from 1006 to 1174 GDD, depending on the weed species present and their densities. Practical implications of this study are that herbicides (pre‐emergence residual or post‐emergence), or other weed control methods should be used in Turkey to eliminate weeds from 1–2 weeks post‐crop emergence up to 11–12 weeks. Such an approach would keep yield loss levels below 5%.
NMR solution structure of a potent cyclic nonapeptide inhibitor of ICAM‐1‐mediated leukocyte adhesion produced by homologous amino acid substitution
Authors: Sillerud L.O. , Burks E.J. , Brown W.M. , Brown D.C. , Larson R.S.
Published: September 2004

Abstract:  We have previously described a disulfide‐linked cyclic nonapeptide (inhibitory peptide‐01, IP01), with the sequence CLLRMRSIC, which binds to intercellular adhesion molecule‐1 (ICAM‐1), and blocks binding to its counter‐structure, the integrin αLβ2 (leukocyte functional antigen‐1, LFA‐1) (Sillerud et al., J. Peptide Res. 62, 2003: 97). We now report the optimization of this peptide by means of single homologous amino acid substitutions to yield a new peptide (IP02‐K6; CLLRMKSAC) which shows an approximately sixfold improvement in inhibitory activity of multivalent leukocyte binding (inhibition constant for 50% inhibition, IC50 = 90 μm) compared with IP01 (IC50 = 580 μm). This improvement in activity gives IP02‐K6 potent in vivo activity in a murine model of ischemia reperfusion injury (Merchant et al., Am. J. Physiol. Heart Circ. 284, 2003: H1260). In order to determine the structural features relevant to ICAM‐1‐binding, we have determined the structure of IP02‐K6 using proton nuclear magnetic resonance (NMR) spectroscopy and restrained molecular modeling. In our previously reported study of solution models of IP01, we observed three interconverting conformations during low‐temperature molecular dynamics simulation. In the present study, we find a single conformation of IP02‐K6 similar to one of the previously found conformations of IP01 (family C). In particular, an R4‐S7 β‐turn is present in similar proportions in both conformation C of IP01 and in IP02‐K6; this motif is important in binding to ICAM‐1 because this turn enables the IP02‐K6 backbone to drape over proline‐36 on ICAM‐1. The NMR‐derived solution model of IP02‐K6 was found to dock at the αLβ2‐binding site on ICAM‐1 with no changes in peptide backbone conformation. This docking model displaced five of the 15 αLβ2 residues at the ICAM‐1‐binding site and provided a rationale for understanding the quantitative relationship between IP02‐K6 structure and biologic activity.
Two polymorphs of a covalent complex between papain and a diazomethylketone inhibitor*
Authors: Janowski R. , Kozak M. , Jankowska E. , Grzonka Z. , Jaskólski M.
Published: September 2004

Abstract:  The three‐dimensional structure of two polymorphs of a ZLFG‐CH2–papain covalent complex has been determined by X‐ray crystallography. The structures indicate that: (i) the methylene carbon atom of the inhibitor is covalently bound to the Sγ atom of Cys25 of papain; (ii) the hydrophobic S2 pocket formed by Pro68, Val133, Val157, and Asp158 is occupied by the inhibitor's phenylalanyl P2 side chain; (iii) extensive hydrogen bonding and hydrophobic interactions are responsible for the interaction of the inhibitor with the enzyme. Comparison with similar structures suggests that in covalent complexes preservation of main chain–main chain interactions between the enzyme and the inhibitor may have higher priority than the P–S interactions.
Antimicrobial activity of arginine‐ and tryptophan‐rich hexapeptides: the effects of aromatic clusters, d‐amino acid substitution and cyclization
Authors: Wessolowski A. , Bienert M. , Dathe M.
Published: September 2004

Abstract:  Many antimicrobial peptides bear arginine (R)‐ and tryptophan (W)‐rich sequence motifs. Based on the sequence Ac‐RRWWRF‐NH2, sets of linear and cyclic peptides were generated by changes in the amino acid sequence, l‐d‐amino acid exchange and naphthylalanine substituted for tryptophan. Linear RW‐peptides displayed moderate activity towards Gram‐positive Bacillus subtilis (15 < MIC < 31 μm) and were inactive against Gram‐negative Escherichia coli at peptide concentrations <100 μm. Cyclization induced high antimicrobial activity. The effect of cyclization was most pronounced for peptides with three adjacent aromatic residues. Incorporation of d‐amino acid residues had minor influence on the biological activity. The haemolytic activity of all RW‐peptides at 100 μm concentration was low (<7% lysis for linear R/W‐rich peptides and <28% for the cyclic analogues). Introduction of naphthylalanine enhanced the biological activities of both the linear and cyclic peptides. All peptides induced permeabilization of large unilamellar vesicles (LUVs) composed of lipids of the membrane of B. subtilis and erythrocytes, but surprisingly had no effect on LUVs composed of lipids of the E. coli inner membrane. The profiles of peptide activity against B. subtilis and red blood cells correlated with the permeabilizing effects on the corresponding model membranes and were related to hydrophobicity parameters as derived from reversed phase high‐performance liquid chromatography (HPLC). The results underlined the importance of amphipathicity as a driving force for cell lytic activity and suggest that conformational constraints and an appropriate position of aromatic residues allowing the formation of hydrophobic clusters are highly favourable for antimicrobial activity and selectivity.
Role of C‐terminal heptapeptide in pore‐forming activity of antimicrobial agent, gaegurin 4
Authors: Kim H.J. , Kim S.S. , Lee M.H. , Lee B.J. , Ryu P.D.
Published: September 2004

Abstract:  Gaegurin 4 (GGN4) is an antimicrobial peptide of 37 amino acids isolated from the skin of a frog, Rana rugosa. GGN4 has a disulfide bond between the residues 31 and 37, which is highly conserved among the antimicrobial peptides isolated from skin of the genus, Rana. However, the role of this C‐terminal heptapeptide motif is not well understood. In this work, we compared the membrane effects of the full‐length GGN4 (C37) and GGN4 1‐30 (C30), which is devoid of the C‐terminal seven amino acids to elucidate the function of the C‐terminal motif. C37 induced significantly larger membrane conductance (>10×) in the model lipid bilayers formed with acidic and neutral phospholipids and larger K+ efflux from gram‐positive (>30×) and gram‐negative bacteria. However, the pores induced by C37 and C30 were not different in their permeability to K+ over Cl− (permeability ratio of K+ to Cl− = 4.8–7.1). In addition, the pore‐forming effect of C37 or C30 in acidic membranes was not different from that in neutral membranes. Furthermore, C37‐induced K+ efflux was not significantly decreased by the reducing agent, dithiothreitol. The results indicate that C‐terminal heptapeptide sequence plays an important role in maintaining the high pore‐forming activity of GGN4, but does not participate in forming GGN4‐induced pore structure. The disulfide bond in this region does not appear critical for such high ionophoric activity of GGN4.
Perspectives of Sorghum in Europe
Authors: Berenji J. , Dahlberg J.
Published: September 2004

This paper attempts to review the present status and offers a perspective on sorghum [Sorghum bicolor (L.) Moench] use and breeding in Europe. Topics such as botany, origin, utilization, agronomic performances and improvement of sorghum are discussed. Clearly, producers and users of sorghum should be more familiar with the crop so that they can take advantage of some of the unique characteristics that are associated with sorghum as it relates to Europe.
Protective Effects of Polyamines against Oxidative Stress Induced by Water and Cold Stress in Chickpea
Authors: Nayyar H. , Chander S.
Published: September 2004

Chickpea (Cicer arietinum L.) yields are drastically reduced by water and cold stress that occur individually or simultaneously in northern region of India. The comparative effects of both the stresses were investigated at the metabolic level by examining the endogenous status of polyamines (PAS), active oxygen species and antioxidants. Chickpea plants (15‐day old) growing hydroponically under controlled conditions (light/ dark; 24/21 °C, 16/8 h; irradiance 250 μmol m−2 s−1) were subjected to water deficit stress (Ψs of −0.2 to −1.0 MPa) and cold stress (5–25 °C) for 4 days. LD50 in terms of root growth rate (RGR), electrolyte leakage and triphenyl tetrazolium chloride (TTC) reduction activity was observed at −0.6 MPa and 10 °C for water and cold stress, respectively. In a subsequent experiment, 15‐day‐old plants were exposed to these stress levels under the above‐mentioned growth conditions for 7 days and analysed for various parameters. In cold‐stressed plants (CS), putrescine (PUT) was observed to be relatively higher while water‐stressed plants (WS) had more of spermidine (SPD). Spermine (SPM) levels increased more rapidly in WS and declined on the fourth day of stress while in CS, a gradual increase occurred that decreased on the seventh day. The accumulation of PAs was short‐lived under the combined presence of both the stresses. Hydrogen peroxide elevated abruptly in WS and remained higher than CS while the latter showed a marked increase in malondialdehyde content. Ascorbic acid increased sharply in WS that decreased on the fourth day while CS showed a relatively gradual increase that reached its maximum on the fourth day and declined subsequently. Glutathione was significantly higher in CS plants in comparison with WS and CS + WS plants. The activity levels of superoxide dismutase were higher up to 4 days and declined subsequently while those of WS stayed higher till the last day of stress. Ascorbate peroxidase levels were significantly higher in CS plants while catalase activity was comparatively more in WS. Exogenous application of PAs reduced the level of hydrogen peroxide, malondialdehyde content and raised the level of antioxidants. Put caused 44 and 32 % increase in RGR in CS and WS, respectively, while SPD resulted in 110 and 25 % enhancement in WS and CS, respectively. Under combination of stresses, RGR increased by 21, 53 and 10 % by Put, SPD and SPM, respectively. The effects of PAs could be reversed largely by their biosynthetic inhibitors. α‐difluoromethylornithine (a biosynthetic inhibitor of putrescine) caused more damage to CS while cyclohexylamine (inhibitor of SPD and SPM biosynthesis) was more inhibitory in WS.
Productivity and Sustainability of Cotton (Gossypium hirsutum L.)–Wheat (Triticum aestivum L.) Cropping System as Influenced by Prilled Urea, Farmyard Manure and Azotobacter
Authors: Das A. , Prasad M. , Shivay Y. S. , Subha K. M.
Published: September 2004

Field experiments were conducted at Indian Agricultural Research Institute, New Delhi, during 2001–2002 and 2002–2003, to study the effect of inorganic, organic and Azotobacter combined sources of N on cotton (Gossypium hirsutum L.) and their residual effect on succeeding wheat (Triticum aestivum L.) crop. The results indicated considerable increase in yield attributes and mean seed cotton yield (2.33 Mg ha−1) with the combined application of 30 kg N and farmyard manure (FYM) at 12 Mg ha−1 along with Azotobacter (M4). The treatment in cotton that included FYM, especially when fertilizer N was also applied could either improve or maintain the soil fertility status in terms of available N, P and K. Distinct increase in yield attributes and grain yield of wheat was observed with the residual effect of integrated application of 30 kg N ha−1 + FYM at 12 Mg ha−1 + Azotobacter. Direct application of 120 kg N ha−1 resulted 67.4 and 17.7 % increase in mean grain yield of wheat over no N and 60 kg N ha−1, respectively. Integrated application of organic and inorganic fertilizer is therefore, recommended for higher productivity and sustainability of the cotton–wheat system.
Root and Shoot Growth of Maize (Zea mays) as Affected by Incorporation of Crotalaria juncea and Tithonia diversifolia as Green Manures
Authors: Sangakkara U. R. , Liedgens M. , Soldati A. , Stamp P.
Published: September 2004

Crop establishment, determined by shoot and root growth during early growth is a vital component in procuring desired plant populations and high yields in rainfed tropical smallholder farming systems, where green manures help maintain soil fertility and sustainability. As green manure incorporation could affect early seedling growth, studies were conduced in a plant house using soils from fields, to evaluate the impact of incorporating two popular tropical green manures (Crotalaria juncea and Tithonia diversifolia) into soil under rainfed field conditions over 3 years, on selected physico‐chemical properties of the soils and on establishment and early shoot and root growth of maize (Zea mays), with and without inorganic fertilizers. In a given year, green manure was grown in one season while maize was grown in the other. A soil that did not receive green manures but was left fallow during the period of green manure cultivation was used as the control treatment. The incorporation of green manures over the 3 years showed trends of increasing soil physical properties, and also the available nitrogen, phosphorus and potassium contents. Incorporation of Crotalaria, with its higher nitrogen content, promoted shoot growth, while Tithonia induced the development of an extended root system. The use of inorganic fertilizers stimulated the beneficial impact of the green manures in promoting shoot and root growth. The use of green manures, especially Tithonia, promoted the development of seminal and nodal roots of maize seedlings, both in the form of length and thickness (based on root surface area) and root length densities, which could assist in successful crop establishment and resource utilization, rather than primary roots. The benefits of using green manures, especially Tithonia, in promoting root growth and Crotalaria in shoot development of maize seedlings even without inorganic fertilizers is presented.
Nitrogen Loss and Wheat (Triticum aestivumL.) Yields in Response to Zero‐tillage and Sowing Time in a Semi‐arid Tropical Environment
Authors: Patra A. K. , Chhonkar P. K. , Khan M. A.
Published: September 2004

A net‐house experiment was conducted at the Indian Agricultural Research Institute, New Delhi, to study the effect of simulated zero‐tillage on the N loss through ammonia (NH3) volatilization, and flux of inorganic N after the sowing of wheat and urea‐N application on two different dates. In addition, the effects of soil perturbation through simulated tillage vs. zero‐tillage, and of sowing time on the wheat yields (above and below‐ground) and N use were examined. Results showed significantly (P < 0.05) higher NH3volatilization loss of N in zero‐tillage than the tillage treatments, but no significant difference between early (18 November) or later (8 December) sowing wheat on such losses. Inorganic N, mostly NH‐N, was significantly higher in undisturbed soil on day 5, whereas on day 15, NO‐N was significantly higher in disturbed soil than the undisturbed (zero‐tilled) soil. There was little difference in NH‐N or NO‐N contents in soils between two dates of sowing. Plant parameters showed no significant (P > 0.05) differences among the treatments in terms of height, spike length, or number of grains per spike, grain and straw yields and root biomass and harvest index. Moreover, there were no significant differences among the treatments when N uptakes were compared. Our results thus suggest that after flooded rice, wheat can be grown successfully on zero‐tilled soils even when adopting sowing dates till early December. More N loss through NH3volatilization in zero‐tilled than tilled soils may not affect growth and yields of wheat, but needs to be reduced for N conservation and environmental reasons.
Prediction in linear mixed models
Authors: Welham Sue , Cullis Brian , Gogel Beverley , Gilmour Arthur , Thompson Robin
Published: September 2004

Following estimation of effects from a linear mixed model, it is often useful to form predicted values for certain factor/variate combinations. The process has been well defined for linear models, but the introduction of random effects into the model means that a decision has to be made about the inclusion or exclusion of random model terms from the predictions. This paper discusses the interpretation of predictions formed including or excluding random terms. Four datasets are used to illustrate circumstances where different prediction strategies may be appropriate: in an orthogonal design, an unbalanced nested structure, a model with cubic smoothing spline terms and for kriging after spatial analysis. The examples also show the need for different weighting schemes that recognize nesting and aliasing during prediction, and the necessity of being able to detect inestimable predictions.
Fitting and comparing seed germination models with a focus on the inverse normal distribution
Authors: O'Neill Michael E. , Thomson Peter C. , Jacobs Brent C. , Brain Phil , Butler Ruth C. , Turner Heather , Mitakda Bernadetha
Published: September 2004

This paper reviews current methods for fitting a range of models to censored seed germination data and recommends adoption of a probability‐based model for the time to germination. It shows that, provided the probability of a seed eventually germinating is not on the boundary, maximum likelihood estimates, their standard errors and the resultant deviances are identical whether only those seeds which have germinated are used or all seeds (including seeds ungerminated at the end of the experiment). The paper recommends analysis of deviance when exploring whether replicate data are consistent with a hypothesis that the underlying distributions are identical, and when assessing whether data from different treatments have underlying distributions with common parameters. The inverse normal distribution, otherwise known as the inverse Gaussian distribution, is discussed, as a natural distribution for the time to germination (including a parameter to measure the lag time to germination). The paper explores some of the properties of this distribution, evaluates the standard errors of the maximum likelihood estimates of the parameters and suggests an accurate approximation to the cumulative distribution function and the median time to germination. Additional material is on the web, at http://www.agric.usyd.edu.au/staff/oneill/.
Performance of localized regression tree splitting criteria on data with discontinuities
Authors: Bremner Alexandra P. , Taplin Ross H.
Published: September 2004

Properties of the localized regression tree splitting criterion, described in Bremner & Taplin (2002) and referred to as the BT method, are explored in this paper and compared to those of Clark & Pregibon's (1992) criterion (the CP method). These properties indicate why the BT method can result in superior trees. This paper shows that the BT method exhibits a weak bias towards edge splits, and the CP method exhibits a strong bias towards central splits in the presence of main effects. A third criterion, called the SM method, that exhibits no bias towards a particular split position is introduced. The SM method is a modification of the BT method that uses more symmetric local means. The BT and SM methods are more likely to split at a discontinuity than the CP method because of their relatively low bias towards particular split positions. The paper shows that the BT and SM methods can be used to discover discontinuities in the data, and that they offer a way of producing a variety of different trees for examination or for tree averaging methods.
Testing for the presence of disease by pooling samples
Authors: Kennedy Nyongesa L.
Published: September 2004

Screening of pooled urine samples was suggested during the Second World War as a method of detecting syphilis in US soldiers. Recently, pooling has been used in screening blood for Human Immunodeficiency Virus (HIV) antibody to help curb the further spread of the deadly virus. Pooling reduces the cost and also reduces the rates of false‐negative results in samples that are not disease‐free, a factor that has led to pooling not being adopted as an efficient procedure for screening HIV. This paper generalizes a common pooling strategy with retesting, and discusses its characteristics. Furthermore, it suggests a new testing strategy with retesting.
Mid‐P confidence intervals based on the likelihood ratio for proportions estimated by group testing
Authors: Hepworth Graham
Published: September 2004

Group testing has been used in many fields of study to estimate proportions. When groups are of different size, the derivation of exact confidence intervals is complicated by the lack of a unique ordering of the event space. An exact interval estimation method is described here, in which outcomes are ordered according to a likelihood ratio statistic. The method is compared with another exact method, in which outcomes are ordered by their associated MLE. Plots of the P‐value against the proportion are useful in examining the properties of the methods. Coverage provided by the intervals is assessed using several realistic grouptesting procedures. The method based on the likelihood ratio, with a mid‐P correction, is shown to give very good coverage in terms of closeness to the nominal level, and is recommended for this type of problem.
Assessing goodness‐of‐fit of categorical regression models based on case‐control data
Authors: Zhang Biao
Published: September 2004

Demonstrated equivalence between a categorical regression model based on case‐control data and an I‐sample semiparametric selection bias model leads to a new goodness‐of‐fit test. The proposed test statistic is an extension of an existing Kolmogorov–Smirnov‐type statistic and is the weighted average of the absolute differences between two estimated distribution functions in each response category. The paper establishes an optimal property for the maximum semiparametric likelihood estimator of the parameters in the I‐sample semiparametric selection bias model. It also presents a bootstrap procedure, some simulation results and an analysis of two real datasets.
Detection of a change point with local polynomial fits for the random design case
Authors: Huh J. , Park B.U.
Published: September 2004

Regression functions may have a change or discontinuity point in the ν th derivative function at an unknown location. This paper considers a method of estimating the location and the jump size of the change point based on the local polynomial fits with one‐sided kernels when the design points are random. It shows that the estimator of the location of the change point achieves the rate n−1/(2ν+1) when ν is even. On the other hand, when ν is odd, it converges faster than the rate n−1/(2ν+1) due to a property of one‐sided kernels. Computer simulation demonstrates the improved performance of the method over the existing ones.
Multi‐sample inference for simple‐tree alternatives with ranked‐set samples
Authors: Ozturk Omer , Wolfe Douglas A. , Alexandridis Roxana
Published: September 2004

This paper develops a non‐parametric multi‐sample inference for simple‐tree alternatives for ranked‐set samples. The multi‐sample inference provides simultaneous one‐sample sign confidence intervals for the population medians. The decision rule compares these intervals to achieve the desired type I error. For the specified upper bounds on the experiment‐wise error rates, corresponding individual confidence coefficients are presented. It is shown that the testing procedure is distribution‐free.

To achieve the desired confidence coefficients for multi‐sample inference, a nonparametric confidence interval is constructed by interpolating the adjacent order statistics. Interpolation coefficients and coverage probabilities are provided, along with the nominal levels.
Estimating the population median using only a central subset of observations
Authors: Huang J.S. , Lin G.D.
Published: September 2004

In estimating the population median, it is common to encounter estimators which are linear combinations of a small number of central observations. Sample medians, sample quasi medians, trimmed means, jackknifed (and delete‐d jackknifed) medians and jackknifed quasi medians are all familiar examples. The objective of this paper is to show that within this class the quasi medians turn out to have the best asymptotic mean squared error.
Buehler confidence limits and nesting
Authors: Kabaila Paul , Lloyd Chris J.
Published: September 2004

The Buehler 1 –α upper confidence limit is as small as possible, subject to the constraints that its coverage probability is at least 1 –α and that it is a non‐decreasing function of a pre‐specified statistic T. This confidence limit has important biostatistical and reliability applications. Previous research has examined the way the choice of T affects the efficiency of the Buehler 1 –α upper confidence limit for a given value of α. This paper considers how T should be chosen when the Buehler limit is to be computed for a range of values of α. If T is allowed to depend on α then the Buehler limit is not necessarily a non‐increasing function of α, i.e. the limit is ‘non‐nesting’. Furthermore, non‐nesting occurs in standard and practical examples. Therefore, if the limit is to be computed for a range [αL, αU]of values of α, this paper suggests that T should be a carefully chosen approximate 1 –αL upper limit for θ. The choice leads to Buehler limits that have high statistical efficiency and are nesting.
Goodness‐of‐fit testing of a weak memoryless property of life distributions
Authors: Ahmad Ibrahim A. , Alwasel Ibrahim A.
Published: September 2004

A life distribution is said to have a weak memoryless property if its conditional probability of survival beyond a fixed time point is equal to its (unconditional) survival probability at that point. Goodness‐of‐fit testing of this notion is proposed in the current investigation, both when the fixed time point is known and when it is unknown but estimable from the data. The limiting behaviour of the proposed test statistic is obtained and the null variance is explicitly given. The empirical power of the test is evaluated for a commonly known alternative using Monte Carlo methods, showing that the test performs well. The case when the fixed time point t0 equals a quantile of the distribution F gives a distribution‐free test procedure. The procedure works even if t0 is unknown but is estimable.
A general inverse sampling scheme and its application to adaptive cluster sampling
Authors: Mohammad Salehi M.  , Seber George A.F.
Published: September 2004

Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation.
Approximating the difference of two t‐variables for all degrees of freedom using truncated variables
Authors: Willink R.
Published: September 2004

A scaled t‐distribution is used to approximate the distribution of a linear combination of two independent t‐variables for any number of degrees of freedom, and in particular for low degrees of freedom where moments do not exist. The approximation is the method‐of‐moments solution to the analogous problem with truncated t‐variables. The approximation exists for all degrees of freedom, is very accurate for more than two degrees of freedom, and performs as well as other approximations of this form when they exist.
Corrected proof of the result of ‘A prediction error property of the Lasso estimator and its generalization’ by Huang (2003)
Authors: Rosset Saharon , Zhu Ji
Published: September 2004

The Lasso achieves variance reduction and variable selection by solving an ℓ1‐regularized least squares problem. Huang (2003) claims that ‘there always exists an interval of regularization parameter values such that the corresponding mean squared prediction error for the Lasso estimator is smaller than for the ordinary least square estimator’. This result is correct. However, its proof in Huang (2003) is not. This paper presents a corrected proof of the claim, which exposes and uses some interesting fundamental properties of the Lasso.
Indigenous Australians and the rules of the social security system: Universalism, appropriateness and justice
Authors: Sanders W.
Published: September 2004

Noel Pearson has recently argued that inclusion, over the last 30 years, in a ‘passive’ welfare system has been to the detriment of Aboriginal society. This article approaches the inclusion of Aboriginal people in the social security system from a slightly different perspective, while taking seriously Pearson's concerns. It argues that, despite norms and aspirations of universalism, rules within the social security system are social constructs derived from and intended for the particular social and economic circumstances of the dominant society. When those rules are applied to the very different social and economic circumstances of minority groups, such as Indigenous Australians, major issues of adaptation and interpretation arise. This article draws on research experience spanning 20 years on relations between Indigenous Australians and the social security system to illustrate the degree to which adaptation has occurred, in the pursuit of realism. However, it also argues that current relations between the social security system and Indigenous Australians are not just and fair because the rules of the system do not equally reflect Indigenous and non‐Indigenous peoples’ social and economic circumstances.
An income‐related loans proposal for drought relief for farm businesses
Authors: Botterill Linda Courtenay , Chapman Bruce
Published: September 2004

In 2004 the Commonwealth government is undertaking a review of its drought policy. This follows expenditure in excess of $1 billion on drought relief during 2002 and 2003 and comes only a decade after similarly large expenditure on support for farmers during the drought of the 1990s. Drought support for farm businesses has been provided within the framework of the National Drought Policy (NDP) agreed by Commonwealth and state governments in 1992 and at present is in the form of interest rate subsidies. This article suggests an alternative form of drought relief for farm businesses based on the Higher Education Contribution Scheme, which is more equitable between farmers, less regressive in its impact on tax payers and less open to politicisation.
Using the tax system to collect fines
Authors: Chapman Bruce , Freiberg Arie , Quiggin John , Tait David
Published: September 2004

In this article we consider the possibility that fines could be collected through the tax and social welfare systems in the same way as higher education contributions and child support payments are currently administered. We argue that the existing system of fine collection and enforcement leads to high default rates and reduces the usefulness of fines as a sanction. We consider a range of models for the implementation of an income‐related fine collection system, and discuss their possible implications for issues including judicial independence, the time taken to repay fines and aggregate fine revenue.
Community legal centres in Australia under a new public management regime
Authors: Rix Mark
Published: September 2004

During the 1990s and into the new millennium the public sector in Australia has gone through a process of so‐called modernisation. This has been underpinned by the New Public Management (NPM), and the financial, regulatory and administrative reforms it encompasses. An assumption that the public and private sectors are not inherently dissimilar, and can therefore be managed in much the same way including having their efficiency and effectiveness measured against the same performance criteria, is central to the NPM. This article examines the role of comunity legal centres (CLCs) in Australian society against the background of adoption by all governments in Australia of an NPM policy agenda. It then goes on to discuss the implications of this agenda for the viability of CLCs and their relationship with government and clients. The article will also consider the implications for relationships between government and citizenry.
Making the most of the best: Formulating a knowledge management strategy for a government advisory body
Authors: Osborne Matthew
Published: September 2004

‘Well, there seems to be a growing consensus among companies doing knowledge management that the correct focus should be neither on the individual nor the enterprise, but instead on some grouping of people who share common context, stories and passion, around a subject’ (Larry Prusak).1

What do you get when some 20 people meet every three or four months, each one at the top of their respective fields and from different organisations and with different backgrounds, in different cities around Australia? In the case of the Family Law Council you get scintillating intellectual pyrotechnics, sharing of insights and even, in a typically understated Australian way, passion.

The Family Law Council (the Council) is a government advisory body. Advisory bodies have two primary functions: to provide expert and representative advice in an increasingly specialised and complex social environment; and to open up channels of communication between government and the people (Hughes 1995).

This article examines how the tools and analytical techniques of knowledge management (KM) can add value to the two primary functions of the Council. Drawing on the conceptual framework of KM, and on the basis that the Council forms a knowledge system, this article will examine the workings of the Council. It will look at its statutory role, environmental background and logistics, in order to propose a KM strategy adapted to its specific circumstances. And it will, where appropriate, illustrate points with discussions based on methodologies and case studies from the flourishing academic field of KM.
Commercialisation of state government legal services
Authors: Girle Alan
Published: September 2004

Most people who have worked in the public sector for over a decade have experienced dramatic change in the way they do business. For some, the change has been rapid. Others have been able to hold onto traditional methods. One area of business steeped in tradition is the area of legal services. In the Queensland public sector, current changes in the way in which legal services are provided reflect many of the changes that have already occurred in other business units. We should learn from the experiences of others, tap into the needs of those utilising legal services and reflect upon the importance of those traditional values. This article argues that the time for a comprehensive and transparent review of legal services in the Queensland public sector is now.
Les liaisons dangereuses: Relations between police commissioners and their political masters
Authors: Fleming Jenny
Published: September 2004

This article reflects on the difficult and ambiguous relationship between Australian Police Commissioners and their political masters. The article looks at South Australia, Queensland and New South Wales and examines the nature of the conflict arising in these jurisdictions from the ambiguous nature of the roles Police Commissioners and Ministers are expected to play. In exploring the uncertainties and expectations that surround the Police Commissioner–Minister relationship, the article considers what lessons can be drawn from such examples. The article reflects on the political and social ramifications of such altercations and considers ways of managing future conflict.