bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance analysis of probabilistic action systems
Authors: Hallerstede Stefan , Butler Michael 
Published: April 2004

Abstract.

Formal notations like B or action systems support a notion of refinement. Refinement relates an abstract specification
A
to a concrete specification
C
that is as least as deterministic. Knowing
A
and
C
one proves that
C
refines, or implements, specification
A
. In this study we consider specification
A
as given and concern ourselves with a way to find a good candidate for implementation
C
. To this end we classify all implementations of an abstract specification according to their performance. We distinguish performance from correctness. Concrete systems that do not meet the abstract specification correctly are excluded. Only the remaining correct implementations
C
are considered with respect to their performance. A good implementation of a specification is identified by having some optimal behaviour in common with it. In other words, a good refinement corresponds to a reduction of non-optimal behaviour. This also means that the abstract specification sets a boundary for the performance of any implementation. We introduce the probabilistic action system formalism which combines refinement with performance. In our current study we measure performance in terms of long-run expected average-cost. Performance is expressed by means of probability and expected costs. Probability is needed to express uncertainty present in physical environments. Expected costs express physical or abstract quantities that describe a system. They encode the performance objective. The behaviour of probabilistic action systems is described by traces of expected costs. A corresponding notion of refinement and simulation-based proof rules are introduced. Probabilistic action systems are based on discrete-time Markov decision processes. Numerical methods solving the optimisation problems posed by Markov decision processes are well-known, and used in a software tool that we have developed. The tool computes an optimal behaviour of a specification
A
thus assisting in the search for a good implementation
C
.
Extratympanic Electrocochleographic Changes on Noise‐Induced Temporary Threshold Shift
Authors: Nam Eui‐Cheol , Won Jun Yeon 
Published: April 2004

OBJECTIVEElectrocochleography (ECoG) is a sensitive evoked‐response test for evaluating changes in cochlear function. We investigated the extratympanic ECoG in a noise‐induced temporary threshold shift (TTS) to evaluate the usefulness of ECoG in the early detection of noise‐induced hearing loss (NIHL).STUDY DESIGN AND METHODSIn a prospective analysis, 15 healthy ears were exposed to 90.3‐ to 105.0‐dB noise for 3 hours in the same computer‐game arcade. Pure‐tone audiometry and ECoG were performed before, immediately after, and 24 hours after the exposure.RESULTSBefore the exposure, the average hearing level was 5.8 ± 2.7 dB, which increased significantly to 12.8 ± 2.8 dB immediately after exposure. A marked increment in the SP/AP (summating potential/action potential) ratio was observed with the TTS. The mean ratio was 0.22 ± 0.11 before the exposure, 0.46 ± 0.18 in the TTS phase, and 0.20 ± 0.11 after resolution.CONCLUSIONThe results of this study suggest that the SP/AP ratio is useful for the early detection and monitoring of NIHL. (Otolaryngol Head Neck Surg 2004;130:437–42.)
Cerebrospinal Fluid Pressure Monitoring after Repair of Cerebrospinal Fluid Leaks
Authors: Schlosser Rodney J. , Wilensky Eileen Maloney , Grady M. Sean , Palmer James N. , Kennedy David W. , Bolger William E. 
Published: April 2004

OBJECTIVETo measure intracranial pressures (ICPs) via lumbar drains after surgical repair of cerebrospinal fluid (CSF) leaks.METHODSWe conducted a retrospective review of ICP measurements through lumbar drains during the immediate postoperative period after CSF leak repair.RESULTSEight patients with spontaneous CSF leaks underwent surgery and postoperative CSF pressures were measured via lumbar drains. ICP was elevated in 7/8 patients (mean, 32.5 cm H2O). Diuretics reduced ICP (mean, 10 cm H2O). Three traumatic CSF leaks patients served as controls (mean, ICP 14 cm H2O).CONCLUSIONMeasurement of ICP through lumbar drains provides important information regarding the pathophysiology of CSF leaks that has an impact on subsequent medical and surgical treatment. Although the precise cause and mechanism of spontaneous CSF leaks are not fully understood, this study indicates that elevated ICP plays a role and that further medical or surgical treatment to correct the intracranial hypertension may be warranted. (Otolaryngol Head Neck Surg 2004;130:443‐8.)
Decreased Ataxia and Improved Balance after Vestibular Rehabilitation
Authors: Cohen Helen S. , Kimball Kay T. 
Published: April 2004

OBJECTIVESTo determine the effects of vestibular rehabilitation on gait ataxia and balance.SETTINGTertiary care center.STUDY DESIGNSubjects were patients with chronic vertigo due to peripheral vestibular impairments, referred for vestibular rehabilitation. They were assessed on the Timed Up and Go test, ataxia during a path integration test, computerized dynamic posturography, level of vertigo, independence in activities of daily living, and psychological locus of control. They were randomly assigned to three home program treatment groups.RESULTSAtaxia decreased significantly, and posturography scores and time to perform Timed Up and Go improved significantly, for all subjects. Improvements were significantly related to scores on the ambulation subtest of the Vestibular Disorders Activities of Daily Living Scale, decreases in vertigo, and increases in locus of control.CONCLUSIONSFor many patients, a simple home program of vestibular habituation head movement exercises is related to reduced symptoms of imbalance during stance and gait. (Otolaryngol Head Neck Surg 2004;130:418–25.)
The role of microtubules in cellular organization and endocytosis in the plant pathogen Ustilago maydis
Authors: Steinberg G. , Fuchs U. 
Published: April 2004

SummaryMicrotubules are an important part of the eukaryotic cytoskeleton, which participates in numerous essential cellular processes. In fungi interphase microtubules mediate cell polarity and participate in polar growth. However, our understanding of their detailed role in fungal growth is just at the beginning. In growing cells of the plant pathogenic fungus Ustilago maydis microtubules are organized by polar microtubule organizing centres that focus the microtubule minus ends at the small bud. Two opposing motor complexes utilize this microtubule polarity. Cytoplasmic dynein and a kinesin of the Unc104/Kif1A family of kinesins mediate rapid bi‐directional transport of early endosomes. A balance of their activity is required for cell cycle‐dependent accumulation of early endosomes at the growth site, the rear cell pole and the region of cell cleavage. Mutant phenotypes suggest that these endosomes participate in polar growth, bud site selection and cell separation. Therefore, our data suggest that endocytotic membrane recycling participates in local exocytosis, and that the microtubule cytoskeleton has a crucial role in this process.
Platelet transfusion in an infant leading to formation of anti‐D: implications for immunoprophylaxis
Authors: Haspel Richard L. , Walsh Lorna , Sloan Steven R. 
Published: April 2004

BACKGROUND: The immature infant immune system rarely makes RBC alloantibodies; however, most studies confirming the absence of alloantibodies in infants have involved transfusions that were matched for one of the most immunogenic antigens, rhesus D. The potential for D– infants to develop anti‐D is unknown. Specifically, this issue has not been analyzed for infants receiving whole‐blood‐derived PLTs from D+ donors. The importance of understanding such risk is underscored by the fact that anti‐D formation can be prevented by the administration of Rh immunoglobulin.CASE REPORT: A D– infant with congenital heart disease received two D‐mismatched whole‐blood‐derived PLT units at 17 weeks of age. He did not receive Rh immunoglobulin prophylaxis. Upon a subsequent admission 13 months later, anti‐D was identified in his plasma sample.CONCLUSION: The case presented here demonstrates that a young infant can respond to less than 0.6 mL of D+ RBCs and documents the youngest patient to have developed a RBC alloantibody from a PLT transfusion. To prevent anti‐D formation, we recommend administering Rh immunoglobulin to all pediatric patients that receive PLT transfusions from D+ donors.
Salivary IgA reactions to cell‐surface antigens of oral streptococci
Authors: Lundin Wallengren M. L. , Hamberg K. , Ericson D. 
Published: April 2004

Background:  In the immunoblot technique, using whole bacteria cell extracts as antigens, both intra‐ and extracellular antigens are detected, which gives a large number of immunoglobulin A (IgA) reactions (immunoblot bands) when incubated with saliva. It is important to distinguish which immunoblot bands represent bacterial cell‐surface antigens, since these antigens could be involved in adhesion mechanisms and be available for blocking in vivo.Methods:  Bacterial extracts of Streptococcus mutans, Streptococcus sobrinus, Streptococcus parasanguis and the streptococcal antigen I/II were separated using SDS–PAGE. The antigens were detected with saliva in Western blot. Untreated saliva and saliva in which cell‐surface reactive IgA had been absorbed with whole bacteria cells were analyzed.Results:  Approximately half the number of the bands were absent for saliva absorbed with homologous cells, compared to untreated saliva. The absorption pattern was almost identical for S. mutans and S. sobrinus but not for S. parasanguis. Salivary IgA reactive against streptococcal antigen I/II was absorbed by S. mutans cells, to a lesser extent by S. sobrinus cells, and not at all by S. parasanguis cells.Conclusion:  It is likely that the bands that were absent after absorption represented cell‐surface antigens. For S. mutans and S. sobrinus, these bands were probably the streptococcal antigen I/II.
Implementation of a strategy to prevent TRALI in a regional blood centre
Authors: Insunza A. , Romon I. , Gonzalez‐Ponte M. L. , Hoyos A. , Pastor J. M. , Iriondo A. , Hermosa V. 
Published: April 2004

summary Transfusion‐related acute lung injury (TRALI) can be a life‐threatening complication of transfusion and it is probably underdiagnosed. Human leucocyte antigen (HLA) and granulocyte antibodies are thought to play a major role, but preventive measures are difficult to implement. In our regional blood centre, we implemented a preventive strategy avoiding donor deferral. Previously, pregnant apheresis donors were screened for HLA antibodies, and those with positive results were assigned to a plasma‐only protocol. Plasma from these donors and from all previously pregnant whole blood donors was diverted for protein fractionation. Plasma‐poor red blood cells (in additive solution, buffy coat removed) and platelets (pools with additive solution) were prepared. Prestorage leucodepletion was also applied.We found HLA antibodies in 18·1% of previously pregnant apheresis donors, and our strategy caused a 6·0% loss of apheresis platelets, a 4·8% increase of apheresis fresh frozen plasma (FFP) and a 7·8% loss of transfusable apheresis FFP. The effect on FFP from whole blood donors could be compensated. The platelet preparation method reduced the mean volume of plasma from each donor to 24·4 mL. Fifteen months after the start of our strategy, no cases of TRALI have been reported. Our experience shows that a practical strategy to prevent TRALI is feasible.
Progression and regression in renal vascular and glomerular fibrosis
Authors: Chatziantoniou Christos , Boffa Jean‐Jacques , Tharaux Pierre‐Louis , Flamant Martin , Ronco Pierre , Dussaule Jean‐Claude 
Published: April 2004

SummaryEnd‐stage renal disease (ESRD) is characterized by the development of fibrotic lesions in the glomerular, interstitial and vascular compartments. Renal fibrogenesis, a common complication of diabetes and hypertension, is a complex dynamic process involving several players such as inflammatory agents, cytokines, vasoactive agents and enzymes participating in extracellular matrix assembly, anchoring or degradation. The only available treatment today against chronic renal failure is dialysis or kidney transplantation, making thus ESRD one of the most expensive diseases to treat on a per‐patient basis. An emerging challenge for clinicians, maybe the nephrologist's Holy Grail in the 21st century, is to stop definitively the decline of renal function and, if possible, to achieve regression of renal fibrosis and restoration of renal structure. Over the last 5 years, different approaches have been tested in experimental models of nephropathy with variable degree of success. In this review, we will focus on the mechanisms of the hypertension‐associated fibrosis and the few recent studies that gave promising results for a therapeutic intervention.
The rationale for antidepressant therapy in functional gastrointestinal disorders
Authors: Castle M. Z. D. , Silk D. B. A. , Libby G. W. 
Published: April 2004

SummaryThe rationale for antidepressants in the treatment of functional gastrointestinal disorders (FGDs) has been the subject of much interest. However, because of our incomplete understanding of FGDs, this rationale remains unclear. A key point is whether the high degree of psychiatric co‐morbidity associated with FGDs (40–90%) represents a shared pathophysiology or the ascertainment bias of tertiary referral patients.Our aims were four‐fold: (i) to review the current rationale for antidepressant therapy in FGDs; (ii) to review the studies comparing the characteristics of FGDs with both organic gastrointestinal disease and psychiatric disorders; (iii) to propose a model of FGDs which explains the high psychiatric co‐morbidity; (iv) to compare the treatment regimes and effectiveness of antidepressants in FGDs and psychiatric illnesses.The review highlights two important observations. Firstly, the characteristics of FGDs are similar to those of affective disorders and dissimilar to those of organic disease. Secondly, although antidepressants benefit FGD sufferers, their benefits in psychiatric illnesses are greater.We conclude that, in view of the degree of similarity between FGDs and affective disorders, FGDs could be considered as affective disorders in their own right and, if the prescription of antidepressants conformed to their use in affective disorders, FGD morbidity would be reduced.
Infliximab downregulates basic fibroblast growth factor and vascular endothelial growth factor in Crohn's disease patients
Authors: Di Sabatino A. , Ciccocioppo R. , Benazzato L. , Sturniolo G. C. , Corazza G. R. 
Published: April 2004

SummaryBackground : The use of infliximab in the treatment of Crohn's disease patients with symptomatic stenosis is controversial.Aim : To explore the influence of this agent on intestinal fibrogenesis by measuring in infliximab‐treated Crohn's disease patients the serum levels of basic fibroblast growth factor and vascular endothelial growth factor, two factors known to be involved in the process of intestinal wound healing and fibrosis in this condition.Methods : Serum levels of basic fibroblast growth factor and vascular endothelial growth factor were determined by enzyme‐linked immunosorbent assay in 22 patients with steroid refractory or fistulizing Crohn's disease before, during (2 weeks) and after 12 weeks of treatment with infliximab, administered at week 0, 2 and 6 in a dose of 5 mg/kg.Results : A substantial improvement in 19 of the 22 Crohn's disease patients was accompanied by a rapid and durable reduction in basic fibroblast growth factor and vascular endothelial growth factor serum levels.Conclusions : The action of infliximab in reducing serum basic fibroblast growth factor and vascular endothelial growth factor would seem to suggest a role of this agent in down‐regulating the process of intestinal fibrogenesis in Crohn's disease.
Incidence of a clinical diagnosis of the irritable bowel syndrome in a United States population
Authors: Locke G. R. , Yawn B. P , Wollan P. C. , Melton L. J. , Lydick E. , Talley N. J. 
Published: April 2004

SummaryBackground : The incidence of irritable bowel syndrome is uncertain. We aimed to determine the incidence of clinically diagnosed irritable bowel syndrome in the community.Methods : Using the Rochester Epidemiology Project, all diagnoses of irritable bowel syndrome made among adult residents of Olmsted County, Minnesota, over a 3‐year period were identified. The complete medical records of a random sample of the potential subjects were reviewed for the 10 years prior to the irritable bowel syndrome diagnosis and any patient who had received a previous diagnosis of irritable bowel syndrome was excluded (prevalent cases).Results : The diagnostic index listed 1245 possible irritable bowel syndrome patients; 416 patient charts were reviewed and, of these, 149 were physician diagnosed incident cases of irritable bowel syndrome. The age‐ and sex‐adjusted incidence rate was 196 per 100 000 person‐years and increased with age (P = 0.006). The age‐adjusted annual incidence per 100 000 in women was higher than in men: 238 vs. 141 (ratio 3:2; P = 0.005). The overall symptom frequency at the time of diagnosis was abdominal pain (73%), diarrhoea (41%) and constipation (16%).Conclusions : The incidence of a clinical diagnosis of irritable bowel syndrome in adults was estimated to be two per 1000 per year, increased with age and was higher in women than men. As many people with irritable bowel syndrome do not seek care, the true incidence of irritable bowel syndrome is likely to be higher.
Cyanobacteria — a neglected component of biodiversity: patterns of species diversity in inland marshes of northern Belize (Central America)
Authors: Rejmánková Eliška , Komárek Jiří , Komárková Jaroslava 
Published: April 2004

ABSTRACTCyanobacterial mats, widely distributed in the inland alkaline marshes of northern Belize and other regions in the Caribbean, are not only important and functionally complex components of these habitats, but they are also significant reservoirs of biological diversity. Highly diverse and (relatively) isolated marshes have provided conditions suitable for cyanoprokaryotic organisms and conditioned the adaptation and stabilization of numerous specialized eco‐ and morphotypes. Species richness of cyanobacteria assemblages follows the conductivity gradient and is highest in the marshes of medium conductivity (c. 1000–2000 µS cm−1) and decreases at low (< 500 µS cm−1) and high (> 3000 µS cm−1) conductivities. This ecologically unique cyanobacterial microflora is very sensitive to nutrient enrichment, both directly and indirectly through shading by expanding macrophytes. Species richness of cyanobacterial assemblages decreases dramatically as a result of eutrophication. Similar cyanobacterial communities are widely distributed in limestone‐based areas of Florida, Central America and Caribbean but none of them is currently under any legal protection status. The purpose of this paper is to bring attention to an ecologically important group of organisms that have traditionally not been considered in species diversity evaluations or conservation efforts.
Angiotensin I‐converting‐enzyme‐inhibitory and antimicrobial bioactive peptides
Authors: Gobbetti Marco , Minervini Fabio , Rizzello Carlo G 
Published: April 2004

Bioactivities of peptides encrypted in major milk proteins are latent until they are released and activated by enzymatic proteolysis. After a brief description of the properties of some bioactive peptides, an overview of the angiotensin I‐converting‐enzyme (ACE)‐inhibitory and antimicrobial peptides is given. Emphasis is on the capacity of lactic acid bacteria to generate ACE‐inhibitory peptides and on the exploitation of the potential role of antimicrobial peptides derived from milk proteins.
Attachment dimensions and sexual motives
Authors: Schachner Dory A. , Shaver Phillip R. 
Published: April 2004

AbstractLittle research has examined the relation between the attachment behavioral system and the sexual behavioral system, although these two systems, along with the caregiving system, are theorized to constitute romantic love (Fraley & Shaver, 2000; Hazan & Shaver, 1987). College students (N = 400) completed measures of two dimensions of attachment style, anxiety and avoidance, and motives for having sex. Anxiety was predicted to be associated with having sex to reduce insecurity and foster intense intimacy. Avoidance was predicted to correlate inversely with having sex to foster intimacy and positively with nonromantic goals, such as increasing one's status and prestige among peers. The results supported both sets of predictions. People high on the attachment anxiety dimension reported having sex to reduce insecurity and establish intense closeness; people high on the attachment avoidance dimension reported having sex to impress their peer group, especially if they were having casual, uncommitted sex. Theoretical and practical implications of the findings are discussed.
Human platelet antigen systems in allogeneic peripheral blood progenitor cell transplantation: effect of human platelet antigen mismatch on platelet engraftment and graft‐versus‐host disease
Authors: García‐Malo M.D. , Corral J. , González M. , Solano C. , González‐Conejero R. , Caballero M.D. , Pérez R. , Moraleda J.M. , Vicente V. 
Published: April 2004

BACKGROUND: Alloimmune incompatibility in allo‐geneic stem cell transplantation (ASCT), pregnancy, and blood transfusion might trigger an immune response with clinical consequences. Human PLT antigens (HPAs), which play a significant role in pregnancy or blood transfusion‐associated alloimmune thrombocytopenia, are also expressed on the surface of tissues affected by GVHD. Thus, HPA mismatch in HLA‐identical ASCT could play a potential role in PLT engraftment and GVHD.STUDY DESIGN AND METHODS: We studied the HPA‐1, ‐2, and ‐5 genotypes in Caucasian donors and patients involved in 77 HLA‐identical ASCTs. We evaluated the association of HPA compatibility with clinical outcome, analyzing the relevance of host‐versus‐donor HPA incompatibility in PLT engraftment and donor‐versus‐host HPA incompatibility in GVHD.RESULTS: PLT engraftment and transfusion require‐ments were similar in HPA‐compatible and HPA‐incompatible ASCT. Cases with severe thrombocytopenia or significant delayed PLT engraftment did not display host‐versus‐donor HPA incompatibility. Moreover, the incidence of GVHD did not correlate with HPA compatibility.CONCLUSION: Our results support no role for these antigens in immune complications of ASCT: PLT engraftment, requirement of PLT transfusions, and GVHD.
Which factors can affect cord blood variables?
Authors: Mohyeddin Bonab M.A. , Alimoghaddam K.A. , Goliaei Z.A. , Ghavamzadeh A.R. 
Published: April 2004

BACKGROUND: The number of nucleated cells (NCs) infused into the recipient is highly correlated with the probability and speed of cord blood (CB) HPC trans‐plantation, therefore it is necessary to obtain CB units with sufficient NCs.STUDY DESIGN AND METHODS: 190 CB units were collected from normal vaginal and caesarian deliveries with placenta in uterus and immediately processed and assessed for volume and NC count. These variables were correlated with maternal and neonatal charac‐teristics such as mother's age, weight, parity, type of delivery, gestational age, baby's birth weight, height, and sex.RESULT: In univariate analysis, total nucleated cell (TNC) count was significantly increased in vaginal deliveries (VDs) (p = 0.001), women older than 25 years (p = 0.02), women with one or two parities (p = 0.03), and babies heavier than 3100 g (p = 0.001). In multiple regression analysis, significant increase was observed only in VDs and heavier babies (p = 0.03, r2= 0.07).CONCLUSION: Our data indicates that VD and heavier babies showed significant increase in TNC by multiple regression analysis. However, r2= 0.07 and even when all factors were considered, r2= 0.16, which is a percentage too insignificant to be applied for ideal CB screening.