bluuebunny/crossref_metadata_2025 huggingface dataset:
Habitat predicts losses of red grouse to individual hen harriers
Authors: Amar Arjun , Arroyo Beatriz , Redpath Stephen , Thirgood Simon
Published: April 2004

Hen harriers Circus cyaneus prey on red grouse Lagopus l. scoticus and high breeding densities of harriers can limit the number of grouse available for shooting in the autumn. Ultimately, grouse hunting contributes to the maintenance of heather moorland, an ecologically important habitat for biodiversity in general and hen harriers in particular. Predation rates vary widely among harrier individuals. Understanding which factors influence this variation would be useful to target management to mitigate the effect of harriers on grouse, such as diversionary feeding.

We used a simple habitat‐based approach to test whether we could identify harrier nests to which most grouse were delivered. Using remote sensing habitat data, we tested whether delivery rates of dead grouse to the nest by hen harriers were higher for those pairs nesting in sites with more heather Calluna vulgaris. A relationship between heather cover and grouse delivery rates might have been expected as grouse densities were correlated with heather cover.

After adjusting for annual variation in grouse abundance, the rate at which grouse were delivered to harrier nests was positively associated with the proportion of heather cover within 2 km of harrier nests. This was primarily due to the positive effect of heather cover on female delivery rates.

This result allowed us to use habitat data to predict the harrier nests to which most grouse chicks would be delivered. Comparison of predictions of the model with observations of food delivery to nests indicated that, in terms of grouse chick delivery, the model correctly predicted the top 50% of harrier nests in five of six years.

We undertook an experiment where carrion was provided to certain harriers at nest sites, in order to decrease their predation on grouse. Data from this experiment showed that when harriers were given diversionary food, the relationship between grouse predation rate and habitat was removed, with grouse predation reduced to negligible levels in most cases. This demonstrated the increased benefit of feeding birds with the highest proportion of heather cover within 2 km of their nest sites, rather than feeding birds at random within the conflict population.

Synthesis and applications. The amount of heather cover around hen harrier nests can be used to predict which pairs will predate most grouse within a population. This information should facilitate targeted management practices, which may accrue greater benefit for grouse stocks and potentially reduce the conflict between grouse shooting and conservation of biodiversity.
Habitat selection by song thrushes in stable and declining farmland populations
Authors: Peach Will J. , Denny Matthew , Cotton Pete A. , Hill Ian F. , Gruar Derek , Barritt David , Impey Andrew , Mallord John
Published: April 2004

Losses of farmland birds from the wider countryside have become a major conservation issue in the UK and Europe. Song thrush Turdus philomelos populations in lowland rural Britain declined by approximately 70% during 1970–95, most severely on intensively managed arable farmland. Comparison between a stable population on mixed farmland and a rapidly declining population on arable farmland revealed fewer nesting attempts each summer by birds in the declining population, and annual productivity was insufficient to maintain local population density. Inadequate food resources were the most plausible cause.

We compared breeding season habitat selection (using radio‐telemetry) and earthworm availability (a major component of summer diet) for song thrushes in the same two farmland populations.

Territory settlement in the mixed farmland landscape involved the selection of field boundaries and woodland and the avoidance of arable crops. Field boundaries and gardens were selected in the arable landscape, while arable break crops and small areas of woodland were avoided.

Habitat selection (intensity of usage) did not change through the breeding season and did not differ between study areas. Scrub, woodland edge, wet ditches and bare soil in gardens were preferred foraging habitats, while cereals were avoided.

Habitat utilization (amount of usage) differed markedly between study areas. Woodland and grassland accounted for 53% of all habitat usage in the mixed farmland landscape compared with just 13% in the arable landscape. Gardens and arable crops were more heavily utilized in the arable landscape, accounting for 58% of all usage compared with 22% in the mixed landscape.

Earthworm availability declined markedly between April and June as surface soils dried out. Lower earthworm availability in the arable landscape was associated with more rapid and pronounced drying of surface soils.

Synthesis and applications. Lack of woodland and grassland, and the faster drying of surface soils in the arable landscape, combined to limit the availability to thrushes of key summer invertebrate prey. Loss of hedgerows, scrub and permanent grassland with livestock, and the wide‐scale installation of under‐field drainage systems, have probably all contributed to the decline of song thrushes on UK arable farmland. New agri‐environment measures may be needed to provide the nesting cover adjacent to invertebrate‐rich damp soils that song thrushes require to sustain annual productivity.
Modelling habitat selection and distribution of the critically endangered Jerdon's courser Rhinoptilus bitorquatus in scrub jungle: an application of a new tracking method
Authors: Jeganathan Panchapakesan , Green Rhys E. , Norris Ken , Vogiatzakis Ioannis N. , Bartsch Annett , Wotton Simon R. , Bowden Christopher G. R. , Griffiths Geoffrey H. , Pain Debbie , Rahmani Asad R.
Published: April 2004

Jerdon's courser Rhinoptilus bitorquatus is a nocturnally active cursorial bird that is only known to occur in a small area of scrub jungle in Andhra Pradesh, India, and is listed as critically endangered by the IUCN. Information on its habitat requirements is needed urgently to underpin conservation measures. We quantified the habitat features that correlated with the use of different areas of scrub jungle by Jerdon's coursers, and developed a model to map potentially suitable habitat over large areas from satellite imagery and facilitate the design of surveys of Jerdon's courser distribution.

We used 11 arrays of 5‐m long tracking strips consisting of smoothed fine soil to detect the footprints of Jerdon's coursers, and measured tracking rates (tracking events per strip night). We counted the number of bushes and trees, and described other attributes of vegetation and substrate in a 10‐m square plot centred on each strip. We obtained reflectance data from Landsat 7 satellite imagery for the pixel within which each strip lay.

We used logistic regression models to describe the relationship between tracking rate by Jerdon's coursers and characteristics of the habitat around the strips, using ground‐based survey data and satellite imagery.

Jerdon's coursers were most likely to occur where the density of large (> 2 m tall) bushes was in the range 300–700 ha−1 and where the density of smaller bushes was less than 1000 ha−1. This habitat was detectable using satellite imagery.

Synthesis and applications. The occurrence of Jerdon's courser is strongly correlated with the density of bushes and trees, and is in turn affected by grazing with domestic livestock, woodcutting and mechanical clearance of bushes to create pasture, orchards and farmland. It is likely that there is an optimal level of grazing and woodcutting that would maintain or create suitable conditions for the species. Knowledge of the species’ distribution is incomplete and there is considerable pressure from human use of apparently suitable habitats. Hence, distribution mapping is a high conservation priority. A two‐step procedure is proposed, involving the use of ground surveys of bush density to calibrate satellite image‐based mapping of potential habitat. These maps could then be used to select priority areas for Jerdon's courser surveys. The use of tracking strips to study habitat selection and distribution has potential in studies of other scarce and secretive species.
New paradigms for modelling species distributions?
Authors: Rushton S. P. , Ormerod S. J. , Kerby G.
Published: April 2004

The management of both desirable and undesirable species requires an understanding of the factors determining their distribution. Quantitative distribution models offer simple methods for formulating the species–habitat link and the means not only for predicting where species should occur, but also for understanding the factors involved. Generalized linear modelling, in particular, links the incidence of species to habitat variables, and has increasingly formed the backbone of the modelling approaches used. New ‘data technologies’, such as remote sensing and geographical information systems, have further broadened these modelling applications to almost any ecological system and any species for which there are distribution data.

Many previous approaches have aimed to identify the most parsimonious model with the best suite of predictors, selected on the basis of null hypothesis testing. However, information‐theoretic approaches based on Akaike's information criterion allow the selection of a best approximating model or a subset of models from a set of candidates. Information‐theoretic approaches require a deeper understanding of the biology of the system modelled and may well become an improved paradigm for species distribution modelling.

Synthesis and applications. This special profile of six papers demonstrates the development in methodology used in species distribution modelling. The papers show how information‐theoretic approaches can be coupled with emerging data technologies to address issues of conservation significance. With conservation biology and applied ecology at the forefront of many of the basic science developments so far, we expect these methods to pervade other areas of ecological research more fully in future.
Conservation genetics of two co‐dominant grass species in an endangered grassland ecosystem
Authors: Gustafson D. J. , Gibson D. J. , Nickrent D. L.
Published: April 2004

Global habitat fragmentation and loss of undisturbed grasslands has led to the use of non‐local seed and cultivars in restoration. There is concern that these sources may be genetically depauperate and their introduction may lead to loss of unique local genotypes. Within this context we considered the issue with regard to the once widespread but now highly fragmented North American tallgrass prairie.

We characterized the genetic diversity and genetic relationships of the co‐dominant species in this system, big bluestemAndropogon gerardiiand Indian grassSorghastrum nutans, from seven remnant and six restored local tallgrass prairies, a non‐local remnant prairie, and five cultivated varieties.

Randomly amplified polymorphic DNA (RAPD) analysis of these grasses showed that genetic diversity was mostly retained within rather than among populations, and did not differ among restored or remnant populations or cultivars.

Genetic diversity estimates were not correlated with the area of the grassland, nor was there a clear association between diversity and species abundance. All of the restored grasslands in this study were established with seed from at least two local populations and were as genetically diverse as remnant sites.

Principal components analysis of RAPD band frequencies showed that the local remnant and restored populations were genetically different from the non‐local remnant grasslands and were consistently different to the cultivars. The genetic relationships among local remnant and restored populations reflected biogeography and human activities.

Synthesis and applications.Restoration practitioners have often assumed that small populations are genetically depauperate and therefore the need for multiple seed sources to increase genetic diversity outweighs concerns over potential genetic differences among widespread species. Our research, however, indicates that genetic diversity is much less of an issue in these perennial outcrossing autopolyploid grasses than genetic differences among local and non‐local or cultivar seed sources. Combining these results with our previous research, indicating differences in plant performance as a function of the source population, suggests that genetic differences and ecological performance among local and non‐local seed sources are more of a concern than genetic diversity. Translocating non‐local seed in order to increase diversity, or using cultivars, is likely to alter the genetic structure of remnant populations and potentially influence the associated community and affect ecosystem structure and function in unforeseen ways.
Combining probabilities of occurrence with spatial reserve design
Authors: Cabeza Mar , Araújo Miguel B. , Wilson Robert J. , Thomas Chris D. , Cowley Matthew J. R. , Moilanen Atte
Published: April 2004

There is a great concern about the loss of biodiversity that calls for more nature protection. Unfortunately, the funding available for conservation is limited, and often a compromise is needed between nature protection and economic interests. Reserve selection algorithms are optimization techniques that concentrate on identifying a set of reserves that represents biodiversity efficiently. Simple approaches to reserve selection use presence–absence data assuming that if a species occurs in a selected reserve, it will persist there indefinitely.

A refinement of this technique is the selection of reserves according to the local probabilities of occurrence of the given species. These can be estimated from habitat models fitted by empirical modelling techniques. However, local probabilities of occurrence are not static, and are influenced by the changing threats to biodiversity in and around the reserves.

The effects of landscape change can be minimized when compact reserves are favoured. Compact reserves that represent all species with a given target probability of occurrence can be achieved by combining the probability approach with spatial reserve design.

In this study we brought together two reserve selection approaches that implicitly deal with biodiversity persistence, by combining habitat models and spatial reserve design in a single algorithm. We applied the combined algorithm to a data set of 26 species of butterflies from north Wales.

For the particular case study addressed in this paper, clustered reserve networks could be identified at no or a small increase in cost.

A new, backwards, heuristic algorithm performed better and more consistently than the regular forwards heuristic approach.

Synthesis and applications. The reserve selection approach presented considers habitat quality (via probabilities of occurrence) and the spatial configuration of the reserves during the selection process. Emphasis on reserve networks that include high‐quality sites in an aggregated manner increases the potential for long‐term persistence of species in the reserve network.
The impact of different intensities of regular donor plasmapheresis on humoral and cellular immunity, red cell and iron metabolism, and cardiovascular risk markers
Authors: Tran‐Mi B. , Storch H. , Seidel K. , Schulzki T. , Haubelt H. , Anders C. , Nagel D. , Siegler K. E. , Vogt A. , Seiler D. , Hellstern P.
Published: April 2004

Background and Objectives  Major studies are still lacking on the impact of differing intensities of long‐term donor plasmapheresis, not only on total serum protein, albumin and immunoglobulin G (IgG), but also on humoral and cellular immunity, red cell and iron metabolism, and biochemical cardiovascular risk markers.

Materials and Methods  Three groups of donors, comprising 483 individuals undergoing differing intensities of long‐term serial plasmapheresis, were entered into a cross‐sectional study. A fourth control group consisted of 100 non‐donors. In addition to measuring total protein, albumin and IgG levels, we determined parameters of humoral and cellular immunity, red cell and iron metabolism and recognized biochemical cardiovascular risk factors.

Results  The median annual net amount of plasma donated by the three donor groups was 37, 16 and 10 l, respectively (P < 0·0001). Donors had significantly lower total serum protein, albumin and IgG levels than non‐donors (P < 0·0001), but the intensity of plasmapheresis had no influence on those parameters. Like non‐donors, all plasma donors had normal humoral and cellular immunity. No increased rates of iron store depletion were observed in the three groups of plasma donors. Plasma donors were not at increased cardiovascular risk.

Conclusions  Regular donor plasmapheresis of up to 45 l of plasma per year appears to be as safe as more moderate plasmapheresis programmes, with respect to the parameters analysed in this study. Individuals donating under these conditions did not develop impaired humoral and cellular immunity, iron store depletion, or increased cardiovascular risk with regard to established biochemical risk markers. Prospective studies are required to determine more exactly than in retrospective analyses the reasons why donors withdraw from plasmapheresis programmes.
Transfusion‐transmitted bacterial infection: risks, sources and interventions
Authors: Wagner S. J.
Published: April 2004

Records of the transmission of bacterial infections by transfusion date back to the beginning of organized blood banking. Despite tremendous strides in preventing viral infection through careful donor screening and viral testing, there has been little improvement in reducing the risk of bacterial sepsis since the introduction of closed collection systems. Based on the French Haemovigilance study, the British Serious Hazards of Transmission (SHOT) study and fatality reports to the United States Food and Drug Administration, the risk of clinically apparent sepsis exceeds the risk of HIV, HBV, and HCV transmission. Sources of contamination include the skin, blood, disposables, and the environment. Potential interventions to reduce transfusion‐associated bacterial sepsis include improvements to donor arm preparation, diversion of the first aliquot of whole blood, introduction of bacterial testing and/or implementation of pathogen reduction methods.
Technical aspects of the development and validation of tests for variant Creutzfeldt‐Jakob disease in blood transfusion
Authors: Minor P. D.
Published: April 2004

The development of tests for variant Creutzfeldt‐Jakob disease in the context of blood transfusion is technically complicated by a number of factors, including the long asymptomatic period and uncertainty as to whether infectivity is present in human blood at all. The specific needs of a donor test impose constraints. It is argued that the only possible analyte will be blood, and that while the initial work will involve animal studies, these will provide only an approximate guide. A rapid infectivity assay is key to confirming positives in human samples, and dilutions of infected human brain will probably provide adequate routine control samples to ensure the correct performance of the test.
Productivity and canopy modification of Medicago arborea as affected by defoliation management and genotype in a Mediterranean environment
Authors: Amato G. , Stringi L. , Giambalvo D.
Published: April 2004

Medicago arborea is one of the most potentially valuable fodder shrubs in a Mediterranean environment because of its high preference by small ruminants and its nutritive value. Edible biomass production is affected by agronomic and environmental factors. A study, carried out in an inland area of Sicily in the growing seasons of 1994/95, 1995/96 and 1996/97, evaluated the forage production and canopy modification in a M. arborea plantation after (i) commencing defoliation 1 or 2 years after transplanting and (ii) defoliating only in autumn (A), only in early summer (S) or in both seasons (A and S). Six clones derived from five different Mediterranean populations were used. Plant age at the first defoliation did not significantly influence forage production. The genotypes differed in growth rate and forage production. The season and frequency of defoliation markedly influenced forage production and canopy size. The highest annual production was obtained by defoliating once a year in early summer (on average, 1·65, 2·85 and 4·50 tonnes ha−1 respectively in the three growing seasons). With the A and S, and A defoliation treatments, production decreased over 3 years by, on average, 0·19 and 0·57 respectively, but the differences became more marked over a 3‐year period. Defoliating only in early summer, however, resulted in an excessive shrub height (>120 cm, 3 years after transplanting), thereby increasing problems of accessibility to small grazing ruminants, and possibly necessitating cutting. On the contrary, the A and S defoliation made it possible to limit the height to <90 cm.
Nitrogen recovery and loss in a fertilized elephant grass pasture
Authors: Martha G. B. , Corsi M. , Trivelin P. C. O. , Alves M. C.
Published: April 2004

Limited information is available regarding the recovery and loss of fertilizer nitrogen (N) applied to intensively managed tropical grass pastures. An experiment was carried out in Brazil to determine the fertilizer‐N recovery and ammonia volatilization loss in an elephant grass (Pennisetum purpureum, Schum.) pasture fertilized with 100 kg N ha−1 as urea or ammonium sulphate, labelled with 15N, in late summer (LS) or in mid‐autumn (MA). Herbage mass was highest and litter mass was lowest in LS (P < 0·05). The N concentration of herbage was highest in autumn (P < 0·05) and the total N content in soil was lower in LS than in MA (P < 0·05), reflecting the high N uptake capacity of the grass. Proportionately higher 15N recovery in litter mass (P < 0·05) was observed in autumn (0·094) than in LS (0·0397) and the 15N recovery in herbage was 0·046 higher for ammonium sulphate‐fertilized pastures (P < 0·05; proportionately 0·243 for ammonium sulphate and 0·197 for urea). Around 0·60 of the fertilizer‐15N recovered was retained in soil and in non‐harvestable fractions of the plant. The NH3 volatilization loss was higher in LS and most of the N loss occurred soon after fertilizer application. Urea and ammonium sulphate fertilizers were equally effective in sustaining herbage dry matter yield in the short term. However, the use of ammonium sulphate, rather than urea, would be preferable for LS applications when the objective is to reduce NH3 volatilization losses.
Seborrheic keratoses: A study comparing the standard cryosurgery with topical calcipotriene, topical tazarotene, and topical imiquimod
Authors: Herron Mark D. , Bowen Anneli R. , Krueger Gerald G.
Published: April 2004

Background  Patients with seborrheic keratoses frequently desire an effective topical therapy for seborrheic keratoses.

Objective  To compare topical calcipotriene, topical tazarotene, and topical imiquimod with standard cryosurgery in the treatment of seborrheic keratoses.

Methods  Fifteen patients with numerous seborrheic keratoses were enrolled in an open‐label study comparing cryosurgery with topical agents. Eight separate seborrheic keratoses were selected to be treated with topical medications. One lesion was treated with cryosurgery.

Results  One treatment with cryosurgery led to clinical and histological improvement of all lesions treated. Neither scarring nor recurrence resulted in cryosurgery. In seven of 15 patients, tazarotene 0.1% cream applied BID caused clinical improvement in lesions within 16 weeks.

Conclusion  Cryosurgery produces clinical and histological improvement of seborrheic keratoses. The result with cryosurgery was cosmetically acceptable to all patients. Responders to tazarotene cream 0.1% found it cosmetically acceptable.
Superficial malignant fibrous histiocytoma presenting as recurrent atypical fibroxanthoma
Authors: Ly Hoang , Selva Dinesh , James Craig L , Huilgol Shyamala C
Published: April 2004

Atypical fibroxanthoma (AFX) and malignant fibrous histiocytoma (MFH) are neoplasms of probable fibrohistiocytic lineage. The precise relationship between AFX and MFH remains controversial. We present two cases in which a lesion was excised from the face of an elderly person and reported as AFX. Both cases recurred within 12 months and were reclassified as MFH. They were excised with slow Mohs' micrographic surgery, with adjuvant radiotherapy in one case. In the other, a further recurrence was treated with orbital exenteration and radiotherapy. We review the difficulties in differentiating between AFX and MFH and the implications for treatment.
Paraneoplastic pityriasis rubra pilaris in association with bronchogenic carcinoma
Authors: Kurzydlo Ann‐Maree , Gillespie Rod
Published: April 2004

Pityriasis rubra pilaris (PRP) is an uncommon dermatosis occasionally reported in association with an underlying malignancy. We report a 61‐year‐old woman in whom PRP preceded the diagnosis of bronchogenic carcinoma by approximately 11 months. The clinical picture in this case included atypical cutaneous signs and mucous membrane involvement. Curative treatment of the malignancy with radiotherapy led to resolution of the mucocutaneous changes within months. A presentation of PRP, particularly if atypical, or in an older patient, should prompt consideration of an associated internal malignancy.
Axillary perifollicular xanthomatosis resembling Fox–Fordyce disease
Authors: Kossard Steven , Dwyer Phillip
Published: April 2004

A 40‐year‐old woman presented with a 2‐year history of intermittently pruritic pale yellow follicular papules localized to both axillae associated with decreased axillary hair growth and sweating. Skin biopsies revealed an expanded perifollicular adventitial sheath packed with xanthoma cells. There was scant lymphocytic inflammation around the follicles. Vacuolated keratinocytes were present within the infundibular region of the follicles. Serum lipid levels and serum protein electrophoresis were both normal. The features in our case overlap those described recently as a xanthomatous variant of Fox–Fordyce disease. However, in our patient the pruritus was not intense, the lesions were confined to the axillae, and the histopathological features of Fox–Fordyce disease were not confirmed. We prefer to classify our case as an axillary perifollicular xanthomatosis. It is possible that axillary perifollicular xanthomatosis is the follicular counterpart of the epidermal‐based verruciform xanthomas, as both are normolipaemic and are limited to the adventitial tissue close to keratinocytes that may be the source of lipid. The finding of vacuolated keratinocytes in the infundibular region in our case may support this mechanism.
Use of biosynthetic dressings in paraneoplastic pemphigus
Authors: Vun Yin Yin , Lun Karyn , Strutton Geoff
Published: April 2004

A 77‐year‐old woman with paraneoplastic pemphigus and non‐Hodgkin's lymphoma was treated with supportive therapy and oral prednisone. Biobrane®, a biosynthetic dressing, was later applied to the extensive areas of erosion to assist in pain management and to provide a temporary barrier function. She reported an improvement in the pain associated with the areas of erosion. The use of biosynthetic dressings in blistering disorders has not been previously reported. Standard dressings such as silver sulfadiazine are messy and can cause discomfort with frequent changing. We feel that this is an area that warrants further evaluation as it may contribute to the overall treatment and comfort cares of these patients.
Defense mechanism to oxidative DNA damage in glial cells
Authors: Iida Takashi , Furuta Akiko , Nakabeppu Yusaku , Iwaki Toru
Published: April 2004

Astrocytosis is a sequential morphological change of astrocytic reaction to tissue damage, and is associated with regulation of antioxidant defense mechanisms to reduce oxidative damage. The repair enzymes to oxidative DNA damage, oxidized purine‐nucleoside triphosphatase (hMTH1) and a mitochondrial type of 8‐oxoguanine DNA glycosylase (hOGG1–2a) in brain tumors and neurons of Alzheimer's disease, were previously reported. In the present study, glial expression of these repair enzymes under such pathological conditions as cerebrovascular diseases and metastatic brain tumors, were investigated. Furthermore, an in‐vitro experiment using a glioma cell‐line under oxidative stress was performed to verify the immunohistochemical results of post‐mortem materials. As a result, hOGG1–2a immunoreactivities in reactive astrocytes were more intense than those to hMTH1. Oligodendrocytes of acute or subacute stage of brain infarction were strongly immunoreactive to both repair enzymes. In‐vitro study revealed that, hOGG1–2a is constitutively expressed in both untreated glioma cells and the glioma cells under oxidative stress. However, although no immunoreactivity to hMTH1 was found in the control cells, accumulation of hMTH1 was rapidly induced by oxidative stress. These results indicate that the two repair enzymes to oxidative DNA damage are differentially regulated in glial cells, and that there is a difference in the expression of the repair enzymes between reactive astrocytes and oligodendrocytes.
Nonvasculitic autoimmune inflammatory meningoencephalitis
Authors: Josephs Keith A. , Rubino Frank A. , Dickson Dennis W.
Published: April 2004

Caselli and colleagues described five cases with encephalopathy, progressive cognitive decline, ataxia, abnormal CSF studies and steroid responsiveness, and proposed the term non‐vasculitic autoimmune inflammatory meningoencephalitis (NAIM). Many of these cases had brain biopsy showing mild leptomeningeal perivascular lymphocytic  inflammation ,  however, none of the cases had a post‐mortem. Nonvasculitic autoimmune mediated meningoencephalitis has been described in patients with Sjogren's syndrome, systemic lupus erythematosus and, more recently, with Hashimoto's disease. The present study is the first post‐mortem report of a case with a clinical diagnosis of NAIM. Neuropathological examination revealed a panencephalitis with intact vessel walls. T and B immunostaining showed a mixture of T and B cells. The findings were not consistent with other reported findings in collagen vascular diseases including Sjogren's syndrome, CNS vasculitis or Hashimoto's encephalopathy. There was no evidence of neoplasia, bacteria, acid‐fast bacilli, fungi or atypical infectious agents. This is the first post‐mortem report of a case with a clinical diagnosis of NAIM and demonstrates a panencephalitis without evidence of a vasculitis. The pathology seems unique, however, Sjogren and Hashimoto's encephalopathy might be variants of NAIM.
Fast Multipath Radiosity using Hierarchical Subscenes
Authors: Castro F. , Sbert M. , Neumann L.
Published: April 2004

This paper presents an efficient acceleration technique for the global line radiosity Multipath method. In this approach, the scene is subdivided in a hierarchy of box bounded subscenes, the boxes subdivided in a grid of virtual patches which store angular information. A new recursive (according to the hierarchy of subscenes) function allows to execute the Multipath algorithm at different levels of the hierarchy. A speed up factor up to 3–4 has been obtained on some of the tested scenes.
Prototype Modeling from Sketched Silhouettes based on Convolution Surfaces
Authors: Tai Chiew‐Lan , Zhang Hongxin , Fong Jacky Chun‐Kin
Published: April 2004

This paper presents a hybrid method for creating three‐dimensional shapes by sketching silhouette curves. Given a silhouette curve, we approximate its medial axis as a set of line segments, and convolve a linearly weighted kernel along each segment. By summing the fields of all segments, an analytical convolution surface is obtained. The resulting generic shape has circular cross‐section, but can be conveniently modified via sketched profile or shape parameters of a spatial transform. New components can be similarly designed by sketching on different projection planes. The convolution surface model lends itself to smooth merging between the overlapping components. Our method overcomes several limitations of previous sketched‐based systems, including designing objects of arbitrary genus, objects with semi‐sharp features, and the ability to easily generate variants of shapes.
Cycles of Crisis and Regulation: the enduring agency and stewardship problems of corporate governance
Authors: Clarke Thomas
Published: April 2004

Corporate governance crisis and reform is essentially cyclical. Waves of corporate governance reform and increased regulation occur during periods of recession, corporate collapse and re‐examination of the viability of regulatory systems. During long periods of expansion, active interest in the conformance aspects of governance diminishes, as companies and shareholders become again more concerned with the generation of wealth, rather than in ensuring governance mechanisms are working appropriately for the retention of wealth, and its use for agreed purposes. This cyclical historical saga revolves around the enduring agency and stewardship dilemmas of governance. Complacency concerning corporate governance during confident times compounds ensuing crises. Such dilemmas are universal in market systems, though internationally with different systems of corporate governance the unwinding of this saga has occurred at different times, for different reasons, and with different consequences. Corporate governance is about wealth generation and risk management, and these duties require continuous and simultaneous performance. Avoiding mandatory restrictive over‐regulation requires active market regulation, particularly at times of expansion. The drive to make corporate governance both improve corporate performance and enhance corporate accountability will continue.
Understanding How Issues in Corporate Governance Develop: Cadbury Report to Higgs Review
Authors: Jones Ian , Pollitt Michael
Published: April 2004

Issues in corporate governance develop according to an identifiable process. Using the influence model of Jones and Pollitt (2002, Understanding How Issues in Business Ethics Develop. Basingstoke: Palgrave), we compare the conduct of and influences on the investigations leading to the Higgs Review (2003) and the Cadbury Report (1992). We suggest that, while there are similarities in the investigations, there are important differences arising from the review process adopted, the role of the government, the background of the leaders of the investigations and the influence of academics. These differences have important implications for the effectiveness of the implementation of the conclusions of the Higgs Review.
The Governance Challenge for Investors
Authors: Montagnon Peter
Published: April 2004

This paper examines how and why corporate governance has come to be of particular interest to investors, locating the discussion in an international context, yet focusing also on the issues raised for the UK, particularly in the light of the Higgs report. It argues that observation and monitoring of corporate governance, with a concern to see well‐governed companies, could prove a wise strategy for investors.
Corporations on the Front Line
Authors: Hertz Noreena
Published: April 2004

Over the past few years multinational corporations have been coming increasingly under attack from a number of forces, including non governmental organisations, “political shoppers” and grass root activists. While these civil or market based forms of regulation have had some effect in moderating corporate behaviour, this paper argues that the effect is necessarily limited. What is proving to be more effective is instead the threat of litigation. Yet despite the evidence, the trend amongst government policy makers has been to encourage corporations to voluntarily self regulate. This paper warns that policy makers pursue this end at the peril not only of external stakeholders, but also of multinational corporations, and lays out steps that governments could take both to improve civil and market regulation, and also to strengthen the law. This paper will argue that such a course of action is in our collective interest.
The Effectiveness of Local Government Active Labor Programs: The Case of the Benefits‐to‐Wages Program in Russia
Authors: Alexandrova Anastasia , Chagin Kirill , Struyk Raymond
Published: April 2004

This paper presents the results of an implementation evaluation of a Benefits‐to‐Wages (BtW) program operated in Perm, Russia. In part because of the low level of support for Active Labor Market Programs (ALPs) by Russian national and regional governments, municipalities have begun implementing ALPs of their own. Participation in the BtW program is limited to an unemployed adult in very low income family where at least one child is present. The program appears to be highly successful, with 74% of applicants finding jobs while still participating in the program. The assessment found that participation in the program, and job acquisition in particular, were important in raising participant families' incomes. Nevertheless, only about 10% of participants with jobs were lifted out of poverty. Receipt of certain social services and Employment Services, including training, had little impact on which participants succeeded in finding a job. Similarly, person attributes, such as education and prior work experience paid no statistically significant role. This pattern is consistent with a situation in which job requirements are modest and are met by most program participants. Various patterns indicate the program did have a positive effect on job acquisition, although the absence of a control group prevents any stronger statement.
The Most Profitable Use of Flow Visualization in the Elimination of Thrombus from a Monopivot Magnetic Suspension Blood Pump
Authors: Yamane Takashi , Maruyama Osamu , Nishida Masahiro , Toyoda Masahiro , Tsutsui Tatsuo , Jikuya Tomoaki , Shigeta Osamu , Sankai Yoshiyuki
Published: April 2004

Abstract:  The purpose of this study was to eliminate fluid dynamic causes of thrombus formation for the monopivot magnetic suspension centrifugal pump under development with the aid of flow visualization as an indirect measurement tool for animal experiments. The formation of thrombus observed in early animal experiments was successfully overcome by combining the multiple washout holes at the center into a single hole, optimizing the hole diameter, and eliminating the pivot gap. Flow visualization was used to optimize the washout hole diameter influencing the flow around the pivot. In animal experiments flow visualization showed that the contours of thrombus corresponded to shear rates of 300 s−1 or 1300–1700 s−1. It was found that flow visualization is a useful technique to predict locations where low shear thrombi form and to optimize the pump design in the development stage.
The influence of Hox genes and three intercellular signalling pathways on enteric neuromuscular development
Authors: Kapur R. P. , Gershon M. D. , Milla P. J. , Pachnis V.
Published: April 2004

Normal intestinal motility requires orderly development of the complex nerve plexuses and smooth muscular layers in the gut wall. Organization of these structures results, in part, from cell autonomous programmes directed by transcription factors, which orchestrate appropriate temporal and spatial expression of specific target genes. Hox proteins appear to function in combination to dictate regional codes that establish major structural landmarks in the gut such as sphincters and muscle layers. These codes are translated in part by intercellular signals, which allow populations of cells in the embryonic gut wall to alter the developmental fate of their neighbours. Some of the best characterized intercellular signalling pathways involved in enteric neurodevelopment are mediated by GDNF/GFRa1/RET, EDN3/ENDRB, and NETRINS/DCC. These signals affect enteric neural precursors as they colonize the gut, and perturbations of these molecules are associated with various types of intestinal neuropathology.
Neurodegeneration: a key factor in the ageing gut
Authors: Wade P. R. , Cowen T.
Published: April 2004

Many individuals experience gastrointestinal (GI) dysfunction more frequently as they age, and the segment of the human population that is growing the most rapidly is the ‘oldest old’, who are ≥ 80 years old. There has recently been renewed interest in the age‐related changes intrinsic to the gut, and these investigations may help physicians understand the ‘normal’ aged GI tract, as distinct from disordered bowel function that is the result of comorbid conditions and/or GI side effects of medications used to treat those conditions. In this concise review we summarize recent data that suggest age‐related neurodegenerative changes in the enteric nervous system (ENS) are key to functional changes observed with advanced age. Morphological studies are reviewed that demonstrate clearly the loss of enteric neurones in both submucosal and myenteric plexuses in humans and in rodents. Recent studies that indicate selective preservation of nitrergic, but not cholinergic, neurones are reviewed, as are preliminary findings that intrinsic sensory neurones may be among the most ‘age‐labile’ subpopulations of the ENS. Caloric restriction remains the only intervention known that prevents neurodegeneration of ageing in the ENS, and mechanisms involved in this phenomenon are discussed. The field of ageing research in enteric neurobiology is ripe for rapid progression from phenomenology of age‐related losses of neurones and associated functional changes to discovery of therapeutic approaches that may help ameliorate deterioration of bowel function and thereby contribute significantly to improved quality of life in advanced age.
Enteric glia
Authors: Rühl A. , Nasser Y. , Sharkey K. A.
Published: April 2004

The enteric nervous system is composed of both enteric neurones and enteric glia. Enteric glial cells were first described by Dogiel and are now known to outnumber neurones approximately 4 : 1. In the past, these cells were assumed to subserve a largely supportive role; however, recent evidence indicates that enteric glial cells may play a more active role in the control of gut function. In transgenic mouse models, where enteric glial cells are selectively ablated, the loss of glia results in intestinal inflammation and disruption of the epithelial barrier. Enteric glia are activated specifically by inflammatory insults and may contribute actively to inflammatory pathology via antigen presentation and cytokine synthesis. Enteric glia also express receptors for neurotransmitters and so may serve as intermediaries in enteric neurotransmission. Thus, enteric glia may serve as a link between the nervous and immune systems of the gut and may also have an important role in maintaining the integrity of the mucosal barrier and in other aspects of intestinal homeostasis.
Slow excitatory metabotropic signal transmission in the enteric nervous system
Authors: Wood J. D. , Kirchgessner A.
Published: April 2004

Metabotropic mechanisms of excitatory signalling in enteric neurones underlie both slow synaptic transmission and paracrine transmission from enteric non‐neuronal cells. The type of neurone in which signalling occurs determines the characteristics of synaptic‐ and paracrine‐mediated slow excitatory responses. Slow excitatory responses in neurones with AH‐type electrophysiological behaviour and multipolar Dogiel type II morphology are characterized by membrane depolarization associated with closure of Ca2+‐gated K+ channels that is reflected by increased neuronal input resistance. Slow excitatory responses in neurones with S‐type electrophysiological behaviour and uniaxonal morphology are characterized by membrane depolarization associated with opening of cationic channels and decreased neuronal input resistance. Postreceptor signalling that involves activation of adenylate cyclase, stimulation of cAMP formation and activation protein kinase A generates excitatory responses characterized by increased neuronal input resistance in AH neurones. Postreceptor signalling that involves activation of phospholipase C, release of IP3 and diacylglycerol and activation of protein kinase C and calmodulin kinases generates excitatory responses characterized by decreased neuronal input resistance in S neurones. Slow excitatory responses that are characterized by increased neuronal input resistance are a property of AH‐type neurones that function as interneurones in the neural networks of the ENS. Slow excitatory responses that are characterized by decreased neuronal input resistance are a property of S‐type neurones that function either as interneurones or as musculomotor and secretomotor neurones in the neural networks of the ENS.
Calcium imaging of gut activity
Authors: Tack J. , Smith T. K.
Published: April 2004

The major cell types regulating gut motility include enteric neurones, interstitial cells of Cajal (ICC) and their effector smooth muscle cells. These cells are arranged conveniently in nested layers through the gut wall. Our knowledge of how many of these cells in each layer are integrated to produce the various patterns of motility is largely unknown. So far, much of our knowledge of gut motility has usually been obtained by examining point sources of activity (e.g. intracellular recordings from enteric neurones, ICC and smooth muscle cells), rather than the spread of activity through these spatially distributed nerve and ICC networks, or smooth muscle syncitia. Our understanding of how these cells are integrated to produce gut movements would be greatly enhanced if we could image the activity in many of these cells in each layer, or many cells in several layers, simultaneously. Calcium (Ca2+) is a major signalling and regulatory molecule in most cells. In fact, electrical excitability in enteric neurones, ICC and smooth muscle is associated with robust rises in intracellular Ca2+ that long outlast the electrical events (e.g. action potentials in neurones and smooth muscle) that gave rise to them. These prolonged Ca2+ responses, together with the development of several high quality Ca2+ indicators, has provided a unique opportunity to image many cells in intact tissues simultaneously using ICCD video‐rate cameras along with conventional microscopy. However, confocal microscopy has also been used, and has several advantages over the above systems. These include reduced photo‐toxicity and bleaching and the elimination of out of focus light from different layers within the tissue. So far, despite some limitations with the calcium imaging techniques, the spread of activity through the two layers of smooth muscle, ICC networks and myenteric neurones in intact preparations, or cultured myenteric neuronal networks, is beginning to yield exciting new data about how these different cells interact and process information.
Regulation of intestinal secretion involved in the interaction between neurotransmitters and prostaglandin E2
Authors: Karaki S.‐I. , Kuwahara A.
Published: April 2004

In this short review, it will be described that neurotransmitter‐induced secretion in the intestine may be influenced by the tissue level of prostaglandin E2 (PGE2). In the normal condition, vasoactive intestinal polypeptide (VIP) and acetylcholine (ACh) are the predominant neurotransmitters of secretomotor neurones. VIP and ACh activate distinct second messenger systems in epithelial cells, i.e. adenosine 3′, 5′‐cyclic monophosphate (cAMP) and calcium ion (Ca2+), respectively. An increase in intracellular cAMP induces a small amount of chloride (Cl–) secretion in epithelial cells, while simultaneous increases in intracellular Ca2+ and cAMP greatly enhances the cAMP‐induced Cl– secretion. When the concentration of prostaglandins reaches a high level in the intestinal tissue substance P, which is a neurotransmitter of sensory neurones, can also induce a massive Cl– secretion by cross‐potentiation of cAMP and Ca2+ in epithelial cells. In conclusion, it is considered that the concentration of tissue PGE2 may indicate tissue alert level, and when this level elevates, PGE2 enhances ACh and SP‐induced Cl– secretion, thus mediating massive fluid secretion for host defence.