bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finding optimal control strategies for invasive species: a density‐structured model forSpartina alterniflora
Authors: TAYLOR CAZ M. , HASTINGS ALAN 
Published: December 2004

SummaryThere are very few general guidelines available to improve the process of eradicating invasive species. We addressed the basic question of whether it is more efficient to prioritize the removal of outliers or core populations of an invasive grass,Spartina alterniflora.We used a structured model in which the population of the invasive species is partitioned into different classes based on local conspecific density in order to investigate density‐based eradication strategies.TheSpartinapopulation at a Pacific coast estuary in Washington state, USA, is subject to an Allee effect: at low density plants produce fewer propagules than in high‐density coalesced meadows. Plants at low density, however, are able to spread faster vegetatively. We used a genetic algorithm to find the optimal division of resources between removal of high‐density and low‐density plants. We explored the consequences of the Allee effect, contrasting financial budgets available for control operations and the inclusion of seedling control in addition to the control of mature plants.We found that the optimal strategy was dependent on the annual budget available for control. At low and medium budgets, it was necessary to remove the low‐density plants first to achieve eradication, but if more money was available then the optimal strategy was to prioritize high‐density areas.Without an Allee effect the optimal strategy would always be to prioritize the removal of fast‐growing, low‐density sub‐populations. Seedling control did not change the optimal strategy but did, in some cases, reduce the cost of eradication.Synthesis and applications. Given the uncertainty in future budgets allocated for control of invasiveSpartina, we recommend a strategy that prioritizes the removal of low‐density subpopulations ofS. alternifloraover high‐density subpopulations. The Allee effect in this system is not sufficiently strong to outweigh the importance of the rapid vegetative spread of the plants at low density.
Ecological requirements of reintroduced species and the implications for release policy: the case of the bearded vulture
Authors: HIRZEL ALEXANDRE H. , POSSE BERTRAND , OGGIER PIERRE‐ALAIN , CRETTENAND YVON , GLENZ CHRISTIAN , ARLETTAZ RAPHAËL 
Published: December 2004

Summary

Species undergoing reintroduction offer a unique opportunity for clarifying their specific niche requirements because they are likely, if sufficiently mobile, to colonize the most suitable habitats first. Information drawn from the individuals released first might thus be essential for optimizing species’ policy as reintroductions proceed.
Bearded vultures were extirpated from the European Alps about a century ago. An international reintroduction programme using birds reared in captivity was launched in 1986; up to 2003, 121 individuals had been released at four different locations. Subsequent dispersion throughout the range has been far from homogeneous, resulting in a clumped occurrence of the first breeding pairs within three main zones that do not necessarily coincide with release areas.
In order to discern ecological requirements we performed a geographical information system (GIS) analysis of bearded vulture sightings collected in Valais (Swiss Alps) from 1987 to 2001. This area harbours no release site, is situated in the core of the Alpine range and has been visited by birds from all four release points.
During the prospecting phase (1987–94, mostly immature birds), the most important variable explaining bearded vulture distribution was ibex biomass. During the settling phase (1995–2001), the presence of birds (mostly maturing subadults) correlated essentially with limestone substrates, while food abundance became secondary.
The selection of craggy limestone zones by maturing bearded vultures might reflect nesting sites that are well protected against adverse weather, as egg laying takes place in the winter. Limestone landscapes, in contrast to silicate substrates, also provide essential finely structured screes that are used for bone breaking and temporary food storage, particularly during chick rearing. Finally, limestone substrates provide the best thermal conditions for soaring.
Synthesis and applications. Extrapolated to the whole Alpine range, these findings might explain both the current distribution of the subadult/adult population and the absence of breeding records for bearded vultures around release sites in landscapes dominated by silicate substrates. As reintroduced bearded vultures tend to be philopatric, we suggest that population restoration would be more efficient if releases were concentrated within large limestone massifs. This case study of the bearded vulture illustrates the need for continual adaptive management in captive release programmes.
POOR NUTRITIONAL STATUS AND INFLAMMATION: The Evidence Against Malnutrition as a Prominent Problem for Chronic Dialysis Patients
Authors: Ahuja Tejinder S. , Mitch William E. 
Published: December 2004

ABSTRACTA large number of dialysis patients have been classified as being malnourished because of anthropometric measurements and laboratory values that are similar to those in patients with protein‐energy malnutrition. Malnutrition implies that abnormalities can be reversed with better nutrition. However, this approach of providing more nutrients in the diet has been unsuccessful in reversing these changes, suggesting that a diagnosis of malnutrition is generally a misdiagnosis for dialysis patients In this review we discuss mechanisms that cause a loss of protein stores, muscle mass, albumin, and other plasma proteins in dialysis patients. We also review the shortcomings of techniques that are used to measure the nutritional status of these patients.
POOR NUTRITIONAL STATUS AND INFLAMMATION: C‐Reactive Protein and End‐Stage Renal Disease
Authors: Lacson Eduardo , Levin Nathan W. 
Published: December 2004

ABSTRACTThe significance of CRP and inflammation has increased over time, especially in the end‐stage renal disease (ESRD) population. From a simple marker it now appears that CRP is an active participant in pro‐atherosclerotic phenomenon including local pro‐inflammatory and thrombotic events. Studies in the general population indicate the usefulness of CRP in prognostication and in monitoring response to therapy. The clinical usefulness of CRP monitoring in chronic kidney disease (CKD) and especially in ESRD deserves closer study. In the meantime, the utility of CRP measurements for monitoring and treatment is on a case‐by‐case basis. Management of traditional cardiovascular risk factors should be considered. In the interest of optimizing therapy it is prudent to use biocompatible membranes and ultrapure water. A careful search for infectious processes in dialysis patients is recommended, with special attention to vascular access sites, periodontitis, gastritis, and other potentially chronic or covert infections. ACE‐inhibitor use should be maximized in all eligible CKD patients. The data on the use of statins in ESRD have been generally positive but await further validation. Individualized use for selected patients is probably beneficial.
POOR NUTRITIONAL STATUS AND INFLAMMATION: Protein and Energy: Recommended Intake and Nutrient Supplementation in Chronic Dialysis Patients
Authors: Ikizler T. Alp 
Published: December 2004

ABSTRACTNutritional status is an important predictor of clinical outcome in end‐stage renal disease (ESRD) patients, especially in patients on chronic hemodialysis. Uremic malnutrition is strongly associated with increased risk of death and hospitalization events in this patient population, and decreased muscle mass is the most significant predictor of these outcomes. Several factors that influence protein metabolism predispose chronic hemodialysis patients to increased catabolism and loss of lean body mass. The available evidence suggests that low protein and energy intake associated with advanced uremia along with catabolic consequences of dialytic therapies can lead to the development of uremic malnutrition. Recent studies show that the hemodialysis procedure induces a net protein catabolic state at the whole‐body level as well as skeletal muscle. There is evidence to suggest that these undesirable effects are due to decreased protein synthesis and increased proteolysis. Provision of nutrients, either in the form of intradialytic parenteral nutrition or oral feeding during hemodialysis, can adequately compensate for the catabolic effects of the hemodialysis procedure. While the mechanisms of these effects are not studied in detail, changes in extracellular amino acid concentrations, along with certain anabolic hormones such as insulin, are important mediators of these actions.
Categorization and validation of handedness using latent class analysis
Authors: Dragovic Milan 
Published: December 2004

Background:A view that handedness is not a dichotomous, i.e. left–right, phenomenon is shared by majority of researchers. However, there are different opinions about the exact number of hand-preference categories and criteria that should be used for their classification.Objectives:This study examined hand-preference categories using the latent class analysis (LCA) and validated them against two external criteria (i.e. hand demonstration test and a series of arbitrary cut-off points).Method:The Edinburgh Handedness Inventory was applied to 354 individuals randomly selected from the general population, and the obtained data were analysed using the LatentGOLD software.Results:Three discrete hand-preference clusters were identified, i.e. left-, right- and mixed-handed category. Further subdivision of hand-preference clusters resulted in a non-parsimonious subcategorization of individuals. There was a good agreement between the LCA-based classification and classification based on hand-preference demonstration tests. The highest agreement between the LCA model and the different types of arbitrary classification criteria ranged between 0 ± 50 and 0 ± 70 of the laterality quotient.Conclusions:The study findings supported the view that handedness is not a bimodal phenomenon. However, definitions and subcategorizations of mixed-handedness using the cut-off points that are outside of the recommended range may lead to misclassification of cases. It is hoped that the categorization and validation of handedness developed in the context of this study will make future research in this area less dependent on arbitrary values and criteria.
The Effect of Helicobacter pylori Infection and Dietary Iron Deficiency on Host Iron Homeostasis: A Study in Mice
Authors: Keenan J. I. , Peterson R. A. , Fraser R. , Frampton C. M. , Walmsley T. A. , Allardyce R. A. , Roake J. A. 
Published: December 2004

ABSTRACTBackground.  Helicobacter pylori, which requires iron to survive, may cause host iron deficiency by directly competing with the host for available iron or by impairing iron uptake as a consequence of atrophy‐associated gastric hypochlorhydria. The aim of this study was to examine the effect of H. pylori infection and dietary iron deficiency on host iron homeostasis in a mouse model.Materials and Methods.  H. pylori SS1‐infected and uninfected C57BL/6 mice, fed either a normal diet or an iron‐deficient diet, were assessed for iron status and infection‐associated gastritis over a 30‐week period.Results.  After 10 weeks, serum ferritin values were higher in H. pylori‐infected mice than in uninfected controls, irrespective of dietary iron intake (p = .04). The infection‐related increase in body iron stores persisted in the iron‐replete mice but diminished over time in mice with restricted dietary iron intake (p < .0001). At 30 weeks serum ferritin levels were lower in these animals (p = .063). No significant difference in bacterial numbers was detected at the 30‐week time point (p > .05) and the histological changes observed were consistently associated with infection (p < .01) and not with the iron status of the mice (p = .771).Conclusions.  Infection with H. pylori did not cause iron deficiency in iron‐replete mice. However, diminished iron stores in mice as a result of limited dietary iron intake were further lowered by concurrent infection, thus indicating that H. pylori competes successfully with the host for available iron.
A Real‐time PCR Assay Based Method for Routine Diagnosis of Spongospora subterranea on Potato Tubers
Authors: Ward L. I. , Beales P. A. , Barnes A. V. , Lane C. R. 
Published: December 2004

AbstractA method is described for the routine diagnosis of Spongospora subterranea on potato tubers. Accurate diagnosis of powdery scab can be difficult and usually relies on observation of resting spores (cystosori) within the scab lesions on diseased tubers. A fast automated extraction method was combined with a real‐time PCR assay using TaqMan® chemistry to improve and advance routine diagnosis of powdery scab on tubers. The diagnostic assay was made more reliable by using as an internal control potato DNA (cytochrome oxidase) which took into account differences in extraction efficiency and guarded against false negative results. The diagnostic assay was validated by testing 37 scabbed tuber samples of various cultivars collected from fields in different locations in the UK. The assay successfully detected S. subterranea in all samples with suspected powdery scab; it also detected S. subterranea in tubers in which cystosori were present and in tubers in which cystosori were not observed. The TaqMan assay was found to be at least 100 times more sensitive than conventional PCR and ELISA.
Dispersal of Venturia inaequalis Ascospores and Disease Gradients from a Defined Inoculum Source
Authors: Holb I. J. , Heijne B. , Withagen J. C. M. , Jeger M. J. 
Published: December 2004

AbstractAerial concentration of ascospores of Venturia inaequalis and incidence of apple scab were monitored in an orchard during the ascospore release seasons in 1999, 2000 and 2001 on susceptible (Jonagold) and moderately resistant (Schone van Boskoop) apple cultivars. A 1‐ha orchard was divided into an inoculum source block (approximately 0.34 ha) and an inoculum‐free block (approximately 0.66 ha) where inoculum was excluded by covering the soil surface with polythene sheets. Ascospore numbers and disease incidence were measured within the inoculum‐free block at different distances from the inoculum block. Ascospores were sampled with three Burkard volumetric spore traps located at 0, 21 and 45 m from the border of the inoculum block. To determine the incidence of infection, clusters of leaves were assessed at six distances from the border of the infected source from the time the first symptoms appeared. Each year, the aerial ascospore concentration significantly decreased with distance from the source, as did the incidence of infected clusters. Cultivar susceptibility to apple scab markedly influenced incidence of infected clusters and disease gradients. The effect of horizontal distance from the source was identifiable up to 18 m and 33 m for cv. Schone van Boskoop and cv. Jonagold, respectively, beyond which disease was negligible. The disease gradients for cultivar Jonagold in 1999, 2000 and 2001 were well described by an exponential model with gradient coefficients of −0.036, −0.042 and −0.047, respectively. The number of infected clusters at the source border for this cultivar differed significantly over the 3 years. A single exponential model with a gradient coefficient of −0.035 adequately described the disease gradients for cultivar Schone van Boskoop in each of the 3 years. Further analysis showed highly significant correlations (r > 0.85, P < 0.01) between the annual cumulative spore catches and the annual mean number of infected leaf clusters in each year and for both cultivars. The aerobiological and epidemiological implications of these findings are discussed.
Molecular Characterization of DNAβ Molecules Associated with Tobacco Leaf Curl Yunnan Virus*
Authors: Cui X. F. , Xie Y. , Zhou X. P. 
Published: December 2004

Abstract Tobacco leaf curl Yunnan virus (TbLCYNV) isolates Y136 and Y143 were both shown to contain DNAβ molecules. Seven DNAβ molecules, each consisting of 1334–1341 nucleotides, were cloned and characterized. Sequence comparison showed that they were of two main types: type 1 included five DNAβ molecules with 75–99% overall nucleotide sequence identity, and type 2 included two DNAβ molecules with >99% overall nucleotide sequence identity. Only 52–54% nucleotide identity was found between the two types of DNAβ molecules. The two isolates were associated with both types of DNAβ. A relationship dendrogram analysis showed that type 1 DNAβ molecules clustered with the DNAβ molecules of Tomato yellow leaf curl China virus, whereas type 2 DNAβ molecules clustered with the DNAβ of Tomato yellow leaf curl Thailand virus. Evidence was also provided that type 2 DNAβ molecules may have arisen by recombination between the DNAβ of Tobacco curly shoot virus and another unidentified virus. To date, only a single type of DNAβ molecule had been found to be associated with one begomovirus. The possible reasons of TbLCYNV associated with two types of DNAβ molecules are discussed.
Identification and Molecular Characterization of Viruses Infecting Cucurbits in Pakistan
Authors: Ali A. , Natsuaki T. , Okuda S. 
Published: December 2004

AbstractCucurbits are grown throughout the North‐West Frontier Province of Pakistan as summer and winter crops. Plants having mosaic, mottling, chlorosis and leaf distortion symptoms were frequently found in most of the cucurbit fields during the survey. Using dot immunobinding assay, Cucumber green mottle mosaic virus (CGMMV), Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV) and Papaya ringspot virus (PRSV) were found infecting cucurbits. CGMMV was widespread, infecting 46.9% of the samples tested followed by ZYMV (14.8%), WMV (12.5%) and PRSV (7.8%). Multiple infections were common with 42% of the samples being infected with two viruses and 8% with three viruses. The nucleotide sequences of the coat protein (CP) genes of these four viruses were determined and deduced amino acid sequence comparisons revealed 88.3–99% similarity of the ZYMV‐Pak isolate with other isolates of ZYMV reported worldwide. The amino acid sequence identity of Pakistani isolates of WMV, CGMMV and PRSV ranged from 96.8 to 98.4%, 98.1 to 99.4% and 79.3 to 84.2%, respectively, with other isolates reported elsewhere. Little variability was observed in the sequences of WMV and CGMMV. ZYMV‐Pak was very close to the USA isolate, and the PRSV‐Pak isolate was close to Indian isolates of PRSV possibly reflecting the geographical relationship between these isolates.
Anesthetic management of the complications of previously undiagnosed ingested foreign body in a pediatric patient
Authors: S Somerville Nicola , Mearns Clare , Chin Chris , Blaney Sean , Anderson David 
Published: December 2004

SummaryA case of a previously undiagnosed ingested foreign body, subsequent acquired tracheoesophageal fistula and airway obstruction in a pediatric patient is described. We suggest that the capability to provide cardiopulmonary bypass was a key factor in this patient's survival.
S‐ketamine and s‐norketamine plasma concentrations after nasal and i.v. administration in anesthetized children
Authors: WEBER FRANK , WULF HINNERK , GRUBER MICHAEL , BIALLAS RALF 
Published: December 2004

SummaryBackground : It has been suggested that nasal administration of s‐ketamine may be used to improve sedation or premedication in combination with nasal midazolam in pediatric patients. In this study we measured and compared plasma concentrations of s‐ketamine and its main metabolite s‐norketamine after nasal and i.v. administration in preschool children.Methods : During sevoflurane anaesthesia, 20 children, aged 1–7 years, weight 11–25 kg, received s‐ketamine 2 mg·kg−1 either intranasally (Group IN, n = 10), or i.v. (Group IV, n = 10). Six venous blood samples were obtained up to 60 min after drug administration for measurement of s‐ketamine and s‐norketamine plasma concentrations.Results : Plasma concentrations [mean ± sd] of s‐ketamine in group IN peaked at 355 ± 172 ng·ml−1 within 18 ± 13 min. vs. 1860 ± 883 ng·ml−1 within 3 ± 1 min. in group IV (P < 0.01). Plasma concentrations of s‐norketamine in group IN peaked at 90 ± 128 ng·ml−1 within 50 ± 11 min. vs. 429 ± 277 ng·ml−1 within 40 ± 16 min. in group IV (P < 0.01). One child in group IN experienced rapid and high level s‐ketamine absorption with a peak plasma concentration of 732 ng·ml−1 after 2 min., which decreased to 274 ng·ml−1 after 60 min. Systolic blood pressure and heart rate remained unaltered in both study groups after s‐ketamine administration.Conclusions : Nasal administration of s‐ketamine 2 mg·kg−1 results in a wide spread of plasma concentrations and absorption times. Rapid and high level drug absorption after nasal drug administration is possible. The use of a pulse oximeter and continuous observation after nasal administration of s‐ketamine for pediatric premedication is recommended.
Clinical signs of infection during continuous postoperative epidural analgesia in children: the value of catheter tip culture
Authors: SETH N. , MACQUEEN S. , HOWARD R. F. 
Published: December 2004

SummaryBackground : Infection arising from the use of epidural catheters for postoperative analgesia is a major source of anxiety.Methods : The routine culture of epidural catheter tips were studied in 100 consecutive children aged 1 day to 15 years.Epidural catheters were inserted aseptically in accordance with an agreed protocol. The catheter site was inspected regularly and the tip sent for microbiological culture following removal.Results : Local signs of inflammation at the epidural site were seen in 16% of children, and bacteria were isolated from catheter tip culture in 32%. Positive catheter tip culture was found in 43% of children with local signs of inflammation and of the remaining children with no local signs, organisms were isolated from the catheter tip in 30%. Culture of skin swabs and catheter tips in two patients with purulent discharge at the epidural site yielded the same organism. No correlation between the number of attempts at catheter insertion and either local signs of inflammation or positive catheter tip cultures were found.Conclusions : Minor local signs of inflammation and infection are common in pediatric patients during continuous epidural infusion. Epidural catheter tips are also frequently culture positive in patients with and without local signs and who may not go on to develop further signs or symptoms of infection. Routine culture of catheter tips is unnecessary as it is not a good predictor of epidural space infection.
Dealing with unfinished Indigenous business: The need for historical reflection
Authors: Alford Katrina , Muir Jan 
Published: December 2004

The commitment by both major political parties to the abolition of the Aboriginal and Torres Strait Islander Commission symbolises profound problems that continue to bedevil movement towards meaningful reconciliation in Australia.Unlike Australia, long‐established treaties in Canada, the United States and New Zealand as well as greater theoretical clarity in identifying the process of colonization and its ill‐effects on Indigenous peoples have provided stronger foundations for policy and more positive outcomes.This article provides a theoretical framework for understanding the effects of colonisation in Australia, and policy prerequisites for redressing its damaging effects. These include a treaty, improved economic resources and stronger political, intellectual and property rights.