bluuebunny/crossref_metadata_2025 huggingface dataset:
Triage in the emergency department – a qualitative study of the factors which nurses consider when making decisions
Authors: Andersson Anna‐Karin , Omberg Monica , Svedlund Marianne
Published: April 2006

Triage, as a concept, is relatively new in Sweden and means ‘sorting’. The triage process was developed to grade patients who needed immediate care. Triage is currently important for the emergency treatment system, and nurses are expected to work with it professionally. The aim of this study is to describe how nurses implement triage when patients arrive at the emergency department of a county hospital, situated in a rural area of Sweden, as well as to highlight the factors considered when prioritizing, in connection with nurses’ decision‐making. The method used was observations of 19 nurses, with minimal disturbance in their triage work, followed by a short tape‐recorded interview, during which the nurses were asked to reflect upon their decision of priorities. Qualitative content analysis of data has been used. The results were divided into two areas, internal factors and external factors. The internal factors reflect the nurse skills and personal capacity. The external factors reflect work environment, including high workload and practical arrangements, and should always be perceived and taken into consideration. Using these factors as a basis, the patients’ clinical condition, clinical history, various examinations and tests form an assessment, which subsequently results in a prioritization.
Dual ant attraction in the Neotropical shrubUrera baccifera(Urticaceae): the role of ant visitation to pearl bodies and fruits in herbivore deterrence and leaf longevity
Authors: DUTRA H. P. , FREITAS A. V. L. , OLIVEIRA P. S.
Published: April 2006

This study investigated the protective role of ants against phytophagous insects onUrera baccifera(L.) Gaudich.Ants (22 species) visit shrubs ofU. bacciferathroughout the year and forage especially on leaves, where they harvest pearl bodies, and on fruiting branches, where they collect fleshy fruits. The main leaf herbivores are the butterfliesSmyrna blomfildia(Fruhstorfer) andUrbanus esmeraldus(Butler), and the mothPleuroptya silicalis(Guené).

The proportion of vegetative (no flowers or fruits) individuals ofU. bacciferaoccupied by ants greatly surpassed that of neighbouring plant species lacking food rewards, consistent with the hypothesis that pearl bodies act as ant attractants. Ant visitation to vegetative individuals ofU. bacciferaincreased larval mortality ofS. blomfildia, suggesting that ants attracted to pearl bodies reduce herbivore survival. Fruits were also demonstrated to play an important role in ant attraction byU. baccifera. Ant visitation to pearl body‐producing shrubs of non‐myrmecophyticPiper amalagoL. withU. bacciferafruits attached was significantly higher than toP. amalagoplants with an attached leaf ofU. baccifera.

Ant‐exclusion experiments showed that ants effectively reduce the incidence of lepidopteran larvae on the plants. In both 2003 and 2004, herbivores were more abundant on ant‐excluded than on ant‐visited shrubs ofU. baccifera. Additionally, in both years ant‐excluded plants had significantly faster leaf abscission rates compared with ant‐visited plants.

So far, all ant–plant systems with dual food rewards involve extrafloral nectar as one of the attractants. This study withU. bacciferais the first to report food bodies and fruits as ant attractants in a non‐symbiotic ant–plant interaction. This facultative system is also unique in that herbivore deterrence caused by pearl body‐ and fruit‐harvesting ants can also add to leaf longevity.
Female modulation of reproductive rate and its role in postmating prezygotic isolation in Callosobruchus maculatus
Authors: FRICKE C. , ARNQVIST G. , AMARO N.
Published: April 2006

Mechanisms that come into play after mating but prior to fertilization can prevent hybrid formation and thus promote reproductive isolation. Recent research indicates that the evolution of such barriers to gene exchange between incipient forms appears to be common and is essential for speciation.

We aimed to test if female Bean Weevils (Callosobruchus maculatus) modulate their reproductive rate and/or remating propensity in response to mating with males with varying degrees of relatedness in a manner that limits the number of ‘hybrids’ produced. We also tested if remating with a male from a female's own population, following a first mating with a foreign male, would elevate egg production.

Females varied their egg‐production rate depending on the relatedness of their mates, but this effect was not in the predicted direction. Heterospecific C. analis males actually elicited the strongest reproductive response in females, which resulted in up to 9% higher egg production. Male relatedness did not significantly affect female propensity to remate with a second male. Further, females did not generally show a compensatory increase in reproductive rate following rematings with males from their own population.

The mechanisms documented here do not act to limit gene flow and are costly to females, as they suffer reduced life span and egg production late in life following a high reproductive rate early in life. We suggest that sexually antagonistic coevolution within species may have caused the pattern observed.
HER2 status in pure ductal carcinoma in situ and in the intraductal and invasive components of invasive ductal carcinoma determined by fluorescence in situ hybridization and immunohistochemistry
Authors: Park K , Han S , Kim H J , Kim J , Shin E
Published: April 2006

Aim : To determine the HER2 status of ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of the breast. The increased prevalence of HER2 amplification and overexpression in DCIS is considered to be maintained in the intraductal component of IDC; however, HER2 amplification and overexpression are detected much less in IDC.

Methods and results : Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were performed to detect HER2 in 270 IDCs with an intraductal component and in 50 pure DCIS samples; IHC was also performed in 116 metastatic nodes. HER2 was found to be amplified in 77 cases (28.5%) and overexpressed in 79 (29.3%) of the 270 IDCs. HER2 amplification was similar between intraductal and invasive components of the same tumour. The concordance for HER2 status between invasive and intraductal components of individual tumours was 98.5% and 99.3% by FISH and IHC, respectively. HER2 was amplified in 25 (50%) of the 50 pure DCIS samples. HER2 overexpression in metastatic nodes resembled the HER2 status in the primary tumour for 108 (93.1%) of 116 cases (κ =0.831).

Conclusion : Our study indicates that the intraductal component of IDC may differ biologically when compared with pure DCIS. HER2 appears to lack a critical role in the progression from DCIS to IDC and HER2 status is maintained in metastatic lesions.
Pigment synthesizing melanoma (so‐called animal type melanoma): a clinicopathological study of 14 cases of a poorly known distinctive variant of melanoma
Authors: Antony F C , Sanclemente G , Shaikh H , Trelles A S , Calonje E
Published: April 2006

Aims : Pigment synthesizing melanoma (so‐called animal type melanoma) (PSM) is a rare histopathological variant of melanoma so termed because of prominent melanin production and its similarity to a variant of melanoma seen in grey horses. The aim of this study was to report the clinicopathological characteristics of 14 cases of animal type melanoma.

Methods and results : Six patients were female and eight were male with ages ranging from 5 to 52 years (mean 31 years, median 39 years). The head and neck represented the most common site. The clinical diagnosis was of melanoma in seven cases, blue naevus in three cases, benign naevus in three cases and a pigmented basal cell carcinoma in one case. The histological diagnosis of PSM was predicated on the basis of an asymmetrical, predominantly intradermal tumour formed of deeply pigmented, round or short, spindle‐shaped dendritic melanocytes with some degree of hyperchromatism and a single nucleolus. Cytological atypia was always present but was not pronounced. A prominent population of macrophages was invariably present. Four tumours were compound and 10 tumours were predominantly intradermal. The mitotic count was usually low, ranging from 1 to 5 per 10 high‐power fields (mean 2). Perineural and lymphovascular invasion was not seen. The Breslow thickness ranged from 1.1 to 7.5 mm (mean 3.3 mm). Follow‐up was available in 13 patients. The median follow‐up period was 5 years. Six patients had no recurrence, three had local recurrence in the form of satellite nodules adjacent to the scar, four had spread to the regional lymph nodes and one patient had distant metastases to the liver. There were no deaths.

Conclusions : This study demonstrates that PSM is a distinctive, possible low‐grade variant of melanoma usually lacking the histological features predictive of aggressive behaviour seen in ordinary melanoma. It should be managed in the same way as other melanomas with wide local excision.
Abundance, spatial variance and occupancy: arthropod species distribution in the Azores
Authors: GASTON KEVIN J. , BORGES PAULO A. V. , HE FANGLIANG , GASPAR CLARA
Published: April 2006

The positive abundance–occupancy and abundance–variance relationships are two of the most widely documented patterns in population and community ecology.

Recently, a general model has been proposed linking the mean abundance, the spatial variance in abundance, and the occupancy of species. A striking feature of this model is that it consists explicitly of the three variables abundance, variance and occupancy, and no extra parameters are involved. However, little is known about how well the model performs.

Here, we show that the abundance–variance–occupancy model fits extremely well to data on the abundance, variance and occupancy of a large number of arthropod species in natural forest patches in the Azores, at three spatial extents, and distinguishing between species of different colonization status. Indeed, virtually all variation about the bivariate abundance–occupancy and abundance–variance relationships is effectively explained by the third missing variable (variance in abundance in the case of the abundance–occupancy relationship, and occupancy in the case of the abundance–variance relationship).

Introduced species tend to exhibit lower densities, less spatial variance in these densities, and occupy fewer sites than native and endemic species. None the less, they all lie on the same bivariate abundance–occupancy and abundance–variance, and trivariate abundance–variance–occupancy, relationships.

Density, spatial variance in density, and occupancy appear to be all the things one needs to know to describe much of the spatial distribution of species.
Dementia and mortality in persons with Down’s syndrome
Authors: Coppus A. , Evenhuis H. , Verberne G.‐J. , Visser F. , Van Gool P. , Eikelenboom P. , Van Duijin C.
Published: April 2006

Background  Numerous studies have documented that persons with Down’s syndrome (DS) are at an increased risk of Alzheimer’s disease (AD). However, at present it is still not clear whether or not all persons with DS will develop dementia as they reach old age.

Methods  We studied 506 people with DS, aged 45 years and above. A standardized assessment of cognitive, functional and physical status was repeated annually. If deterioration occurred, the patients were examined and the differential diagnosis of dementia was made according to the revised Dutch consensus protocol and according to the ICD‐10 Symptom Checklist for Mental Disorders. We compared our findings with those reported in the literature.

Results  The overall prevalence of dementia was 16.8%. Up to the age of 60, the prevalence of dementia doubled with each 5‐year interval. Up to the age of 49, the prevalence is 8.9%, from 50 to 54, it is 17.7%, and from 55 to 59, it is 32.1%. In the age category of 60 and above, there is a small decrease in prevalence of dementia to 25.6%. The lack of increase after the age of 60 may be explained by the increased mortality among elderly demented DS patients (44.4%) in comparison with non‐demented patients (10.7%) who we observed during a 3.3‐year follow‐up. There was no decrease in incidence of dementia in the age group of 60 and above. Our findings are very similar to those published in the literature. Patients with dementia were more frequently treated with antiepileptic, antipsychotic and antidepressant drugs. The history of depression was strongly associated with dementia.

Conclusions  Our study is one of the largest population‐based studies to date. We found that despite the exponential increase in prevalence with age, the prevalence of dementia in the oldest persons with DS was not higher than 25.6%.
Apolipoproteins AI and B as therapeutic targets
Authors: CHARLTON‐MENYS V. , DURRINGTON P.
Published: April 2006

Currently the apolipoprotein B : AI ratio integrates information about the potential for cardiovascular disease (CVD) risk reduction better than any other lipid or lipoprotein index. Certainly it could, with benefit, replace serum cholesterol and HDL cholesterol in the estimation of CVD risk. Defining the therapeutic target of statin therapy in terms of serum apolipoprotein B (apo B) rather than LDL cholesterol could also help to optimize statin treatment. Deciding whether a therapeutic response is adequate also requires knowledge of whether there is persisting hypertriglyceridaemia, because this gives an indication of whether small dense LDL is likely to have been satisfactorily reduced. Raising low levels of HDL, probably best measured as apo AI, may also prove to be an important aim of treatment. This is, however, a more complex issue and also depends on the mechanism by which a particular therapy alters HDL levels and on whether the capacity of HDL to perform its anti‐inflammatory and antioxidative functions is restored. A meta‐analysis of randomized clinical trials of statins in which apo B and apo AI have been reported could provide valuable information.
Errors that result from using the TC/HDL C ratio rather than the apoB/apoA‐I ratio to identify the lipoprotein‐related risk of vascular disease
Authors: SNIDERMAN A. D. , JUNGER I. , HOLME I. , AASTVEIT A. , WALLDIUS G.
Published: April 2006

The objective of this analysis was to demonstrate the frequency and extent of error that results from using the TC/HDL C ratio rather than the apoB/apoA‐I ratio to estimate the lipoprotein‐related risk of vascular disease within 94 667 men and 75 675 women in the Apoprotein‐related Mortality Risk (AMORIS) cohort. The odds ratio (OR) for the risk of fatal myocardial infarction was determined for 1 SD change in the apoB/apoA‐I ratio and all the conventional cholesterol ratios – TC/HDL C ratio, LDL C/HDL C ratio, non‐HDL C/HDL C ratio. In both men and women, the apoB/apoA‐I ratio was significantly greater than any of the cholesterol ratios, which, in fact, differed little. Therefore, the apoB/apoA‐I ratio was taken as the most accurate index of the lipoprotein‐related risk of vascular disease. Using Receiver Operating Characteristic analysis, it was demonstrated that the diagnostic accuracy of the apoB/apoA‐I ratio was significantly greater than any cholesterol ratio in those with an LDL cholesterol <3.6 mmol L−1 compared to those with an LDL cholesterol >3.6 mmol L−1. Indeed, the difference between the apoB/apoA‐I OR compared with the TC/HDL C OR progressively widened as risk increased. This suggests that the advantage of the apoB/apoA‐I ratio is greatest in the population at highest risk. The distribution of subjects by quintiles showed in both genders that whilst agreement was greatest at the extremes, even at these points there was substantial discordance between the TC/HDL C and the apoB/apoA‐I ratios. Within the middle of the distribution, less than 50% of the values were concordant. Finally, when comparing the ORs, the TC/HDL C ratio underestimated risk in 69.4% of male subjects and overestimated risk in 26.1% of male subjects, whereas in the female subjects, the TC/HDL C ratio underestimated risk in 84.9% of the subjects and overestimated risk in 12.0%. Thus, using the conventional cholesterol ratios rather than the apoB/apoA‐I ratio results in frequent and substantial error in the estimation of the lipoprotein‐related risk of vascular disease.
Hepatitis B virus blood screening: unfinished agendas
Authors: Comanor L. , Holland P.
Published: April 2006

The risk of transfusion‐transmitted hepatitis B virus (TTHBV) has been steadily reduced through the use of volunteer donors, enhanced donor questioning, and increasingly sensitive hepatitis B surface antigen (HBsAg) tests. In a few countries, screening by antibody to hepatitis B core antigen (anti‐HBc) and/or hepatitis B virus (HBV) nucleic acid amplification tests (NAT) has also been introduced. Nevertheless, the risk of TTHBV in most countries is higher than the risk of either human immunodeficiency virus‐1 (HIV‐1) or hepatitis C virus (HCV). HBV screening practices vary both in terms of the markers screened and the tests employed, and are often dependent on a country's healthcare resources. Anti‐HBc screening could be employed as an additional safety feature in HBV low‐prevalence countries, but would lead to the rejection of a high percentage of otherwise acceptable donations in HBV moderate‐ and high‐prevalence countries. It has been argued that only individual‐donor HBV NAT testing would substantially reduce the risk of TTHBV beyond that achieved by the most sensitive HBsAg tests. However, studies from countries with low, moderate and high HBV prevalence have demonstrated NAT yield from window period‐ and late stage HBV‐infected donors, even using minipool testing following the most sensitive HBsAg tests.
Robust Tests in Semiparametric Partly Linear Models
Authors: BIANCO ANA , BOENTE GRACIELA , MARTÍNEZ ELENA
Published: April 2006

Abstract. This paper focuses on the problem of testing the null hypothesis that the regression parameter equals a fixed value under a semiparametric partly linear regression model by using a three‐step robust estimate for the regression parameter and the regression function. Two families of tests statistics are considered and their asymptotic distributions are studied under the null hypothesis and under contiguous alternatives. A Monte Carlo study is performed to compare the finite sample behaviour of the proposed tests with the classical one.
Metabolic and Genetic Risk Factors for Migraine in Children
Authors: Bottini F , Celle ME , Calevo MG , Amato S , Minniti G , Montaldi L , Di Pasquale D , Cerone R , Veneselli E , Molinari AC
Published: April 2006

Migraine can induce ischaemic stroke, and is considered an independent risk factor for stroke in the young. To date, the nature of the link between migraine and stroke is essentially unknown. Forty-five children were studied. Homocysteine levels (fasting and post methionine load), vitamin B12 and plasma folate levels, factor V Leiden, factor II G20210A, methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C mutations were examined. Compared with controls, patients with migraine had higher levels of post-methionine load homocysteine values (19.5 ± 4.9 vs. 16.9 ± 1.9; P = 0.025) and significantly lower folate levels (5.8 ± 2.6 vs. 7.5 ± 2.1; P = 0.002). We found a trend toward an increased risk of migraine in subjects carrying a homozygous mutant genotype for MTHFR C677T and MTHFR A1298C polymorphisms. Genetic prothrombotic conditions do not seem to be related to migraine in the young, whereas the biochemical differences between migrainous patients and controls are an appealing topic for further investigation.
Heritability and Expression of C‐Reactive Protein in Type 2 Diabetes in the Diabetes Heart Study
Authors: Lange Leslie A. , Burdon Kathryn , Langefeld Carl D. , Liu Yongmei , Beck Stephanie R. , Rich Stephen S. , Freedman Barry I. , Brosnihan K. Bridget , Herrington David M. , Wagenknecht Lynne E. , Bowden Donald W.
Published: April 2006

Elevated C‐reactive protein (CRP) levels are associated with both prevalent and incident cardiovascular disease. In this study, familial aggregation was estimated, and we tested for association between serum CRP levels and polymorphisms within the CRP and APOE genes in sib‐ships with type 2 diabetes mellitus, a population at increased risk for cardiovascular disease. CRP levels were determined in 461 diabetes‐affected subjects from 224 sibships from the Diabetes Heart Study (DHS). Heritability estimates of CRP levels were obtained using variance component models. Genetic influence on serum CRP levels by single nucleotide polymorphisms (SNPs) in the CRP and APOE genes was evaluated by association analysis using mixed models. Subjects were Caucasian American (84%) and African‐American (16%), 53% female, and had an average age of 62.2 ± 9.2 years. The median CRP level was 3.3 mg/L (range 0 to 59.3 mg/L), and estimated heritability for CRP was approximately 40%. Estimates of heritability were significantly greater than zero (P < 0.0001) and relatively constant, despite adjustments for important modifiers (age, sex, ethnicity, diabetes duration, statin‐use and anti‐inflammatory use) of CRP. There was no significant evidence for association of CRP levels with CRP gene SNPs; however, consistent with previous reports, there was significant evidence of association of CRP levels with polymorphisms within the APOE gene. These data indicate CRP levels are significantly influenced by genetic (and/or environmental) factors that are shared within DHS families. While the APOE locus shows evidence of contributing to CRP levels, no evidence of CRP gene polymorphism association with CRP levels was observed.
The Swedish Blood Pass project
Authors: Berglund B. , Ekblom B. , Ekblom E. , Berglund L. , Kallner A. , Reinebo P. , Lindeberg S.
Published: April 2006

Manipulation of the blood's oxygen carrying capacity (CaO2) through reinfusion of red blood cells, injections of recombinant erythropoietin or by other means results in an increased maximal oxygen uptake and concomitantly enhanced endurance performance. Therefore, there is a need to establish a system –“A Blood Pass”– through which such illegal and unethical methods can be detected. Venous blood samples were taken under standardized conditions from 47 male and female Swedish national and international elite endurance athletes four times during the athletic year of the individual sport (beginning and end of the preparation period and at the beginning and during peak performance in the competition period). In these samples, different hematological values were determined. ONhes and OFFhre values were calculated according to the formula of Gore et al. A questionnaire regarding training at altitude, alcohol use and other important factors for hematological status was answered by the athletes. There were some individual variations comparing hematological values obtained at different times of the athletic year or at the same time in the athletic year but in different years. However, the median values of all individual hematological, ONhes and OFFhre, values taken at the beginning and the end of the preparation or at the beginning and the end of the competition period, respectively, as well as median values for the preparation and competition periods in the respective sport, were all within the 95% confidence limit (CI) of each comparison. It must be mentioned that there was no gender difference in this respect. This study shows that even if there are some individual variations in different hematological values between different sampling times in the athletic year, median values of important hematological factors are stable over time. It must be emphasized that for each blood sample, the 95% CI in each athlete will be increasingly narrower. The conclusion is that there is a physiological basis for establishing an individual‐based “Blood Pass” system, mainly for athletes competing at the international level. On indications of manipulations of hemoglobin concentration and red cell mass by deviations from established “Blood Pass” data, more specific methods can be applied.
Early dental management of patients with Mobius syndrome
Authors: Magalhães MHCG , Araújo LCA , Chiaradia CC , Fraige A , Zamunaro MT , Mantesso A
Published: April 2006

Objective(s):  The aim of this study was to evaluate the orofacial manifestations in patients with Mobius syndrome (MS), establish an early adequate dental treatment and discuss the possible etiology of all cases examined based on information about the gestational intercurrences.

Design:  Prospective study.

Setting:  Special Care Dentistry Center, School of Dentistry, University of Sao Paulo, Brazil.

Subject(s) and methods:  Twenty‐nine patients with MS aged 0 to 4 underwent prospective dental examination as well as early orthodontic treatment.

Results:  All patients presented micrognathia, lack of lip seal, high arched palate and weak soft palate. The use of orthopedic appliances was recommended to all 29 patients, but only 13 adhered to treatment and were monitored for at least 24 months. We observed that, after 24 months of treatment, the palate was expanded and micrognathia became less severe in the majority of the cases. Pregnancy‐related complications were reported by 27 (97%) of the 29 mothers.

Conclusion(s):  The early use of orthopedic appliances was important to prevent malocclusion and glossoptosis. Attempted abortion with misoprostol is associated with an increased risk of MS in infants.
Tolerance to the Therapeutic Effect of Tadalafil Does Not Occur During 6 Months of Treatment: A Randomized, Double-Blind, Placebo-Controlled Study in Men with Erectile Dysfunction
Authors: McMahon Chris G. , Carson Culley C. , Fischer Christopher J. , Wang Wei Christine , Florio Vincent A. , Bradley John D.
Published: April 2006

Introduction

Tolerance can cause a decrease in drug efficacy during chronic therapy, possibly leading to treatment failures.

Aim

The aim of this article is to determine whether tolerance developed to the effects of tadalafil on erectile function (EF) over a 6-month treatment period.

Methods and Main Outcome Measures

Post hoc analysis of data from a multicenter, double-blind, randomized, placebo-controlled, parallel group study was performed. Men (≥18 years of age) with erectile dysfunction (ED) were randomized to treatment with placebo (N = 47) or 20-mg tadalafil (N = 93) taken as needed for 6 months. This report focuses on efficacy assessed with the Sexual Encounter Profile (SEP) diary (diaries were collected after a 4-week treatment-free run-in period [baseline], and monthly for 6 months), and with the International Index of Erectile Function (IIEF) (administered at baseline, and at 3 and 6 months).

Results

The mean per-patient percentage “yes” response on SEP question 3 (SEP3, successful intercourse) was 33 ± 4% at baseline, 74 ± 4% after 1 month, and 78 ± 4% after 6 months of tadalafil treatment. The IIEF EF domain score was 16.2 ± 0.7 at baseline, 24.3 ± 0.8 after 3 months, and 24.3 ± 0.9 after 6 months of tadalafil treatment. In a subgroup of patients who took tadalafil ≥3 times per week (N = 24), the SEP3 score was 87 ± 4% after 1 month and 93 ± 3% after 6 months of treatment, and the IIEF EF domain score was 27.3 ± 0.9 after 3 months and 28.5 ± 0.4 after 6 months. Of 16 tadalafil-treated patients who discontinued, three cited a lack of efficacy.

Conclusions

Tadalafil treatment significantly improved SEP3 and IIEF EF domain scores. The efficacy of tadalafil, taken as needed, was maintained over a 6-month treatment period in men with ED.
Bifunctional Acyclic Nucleoside Phosphonates. 1. Symmetrical 1,3-Bis[(phosphonomethoxy)propan-2-yl] Derivatives of Purines and Pyrimidines
Authors: Vrbovská Silvie , Holý Antonín , Pohl Radek , Masojídková Milena
Published: April 2006

We report here a general method for the synthesis of new symmetrical bis-phosphonates of acyclic nucleosides. 1,3-Bis[(diisopropoxyphosphoryl)methoxy] derivatives of purine and pyrimidine bases were prepared by their reaction with 1,3-bis[(diisopropoxyphosphoryl)-methoxy]propan-2-yl tosylate. Cytosine, uracil and thymine provided regiospecificallyN1-isomers. This alkylation regiospecificity applies to several other tosylates of primary and secondary alcohols as well. 6-Chloropurine and 2-amino-6-chloropurine were alkylated in N9position. Resulting bis-phosphonates were converted to the respective free phosphonic acids and tested for antiviral and cytostatic activity. Despite the fact that no biological activity was found so far, the outcome of this work can serve as a useful tool in synthesis of novel groups of acyclic nucleoside phosphonates (ANPs).
A STOCHASTIC DERIVATION OF THE GEODESIC RULE
Authors: KALOGEROPOULOS NIKOS
Published: April 2006

We argue that the geodesic rule, for global defects, is a consequence of the randomness of the values of the Goldstone field ϕ in each causally connected volume. As these volumes collide and coalescence, ϕ evolves by performing a random walk on the vacuum manifold [Formula: see text]. We derive a Fokker–Planck equation that describes the continuum limit of this process. Its fundamental solution is the heat kernel on [Formula: see text], whose leading asymptotic behavior establishes the geodesic rule.
β-Subunit of cardiac Na+-K+-ATPase dictates the concentration of the functional enzyme in caveolae
Authors: Liu Lijun , Askari Amir
Published: April 2006

Previous studies showed the presence of a significant fraction of Na+-K+-ATPase α-subunits in cardiac myocyte caveolae, suggesting the caveolar interactions of Na+-K+-ATPase with its signaling partners. Because both α- and β-subunits are required for ATPase activity, to clarify the status of the pumping function of caveolar Na+-K+-ATPase, we have examined the relative distribution of two major subunit isoforms (α1 and β1) in caveolar and noncaveolar membranes of adult rat cardiac myocytes. When cell lysates treated with high salt (Na2CO3 or KCl) concentrations were fractionated by a standard density gradient procedure, the resulting light caveolar membranes contained 30–40% of α1-subunits and 80–90% of β1-subunits. Use of Na2CO3 was shown to inactivate Na+-K+-ATPase; however, caveolar membranes obtained by the KCl procedure were not denatured and contained ∼75% of total myocyte Na+-K+-ATPase activity. Sealed isolated caveolae exhibited active Na+ transport. Confocal microscopy supported the presence of α,β-subunits in caveolae, and immunoprecipitation showed the association of the subunits with caveolin oligomers. The findings indicate that cardiac caveolar inpocketings are the primary portals for active Na+-K+ fluxes, and the sites where the pumping and signaling functions of Na+-K+-ATPase are integrated. Preferential concentration of β1-subunit in caveolae was cell specific; it was also noted in neonatal cardiac myocytes but not in fibroblasts and A7r5 cells. Uneven distributions of α1 and β1 in early and late endosomes of myocytes suggested different internalization routes of two subunits as a source of selective localization of active Na+-K+-ATPase in cardiac caveolae.
Time Course of Oculomotor Inhibition Revealed by Saccade Trajectory Modulation
Authors: McSorley Eugene , Haggard Patrick , Walker Robin
Published: April 2006

Selecting a stimulus as the target for a goal-directed movement involves inhibiting other competing possible responses. Both target and distractor stimuli activate populations of neurons in topographic oculomotor maps such as the superior colliculus. Local inhibitory interconnections between these populations ensure only one saccade target is selected. Suppressing saccades to distractors may additionally involve inhibiting corresponding map regions to bias the local competition. Behavioral evidence of these inhibitory processes comes from the effects of distractors on oculomotor and manual trajectories. Individual saccades may initially deviate either toward or away from a distractor, but the source of this variability has not been investigated. Here we investigate the relation between distractor-related deviation of trajectory and saccade latency. Targets were presented with, or without, distractors, and the deviation of saccade trajectories arising from the presence of distractors was measured. A fixation gap paradigm was used to manipulate latency independently of the influence of competing distractors. Shorter-latency saccades deviated toward distractors and longer-latency saccades deviated away from distractors. The transition between deviation toward or away from distractors occurred at a saccade latency of around 200 ms. This shows that the time course of the inhibitory process involved in distractor related suppression is relatively slow.
On calculation of the relative index of a fixed point in the nondegenerate case
Authors: Guminskaya A. V. , Zabreiko P. P.
Published: April 2006

The paper is devoted to the calculation of the index of a zero and
the asymptotic index of a linear completely continuous nonnegative
operator. Also the case of a nonlinear completely continuous
operator A whose domain and image are situated in a closed convex
set Q of a Banach space is considered. For this case, we
formulate the rules for calculating the index of an arbitrary
fixed point and the asymptotic index under the assumption that the
corresponding linearizations exist and the operators of derivative
do not have eigenvectors with eigenvalue 1 in some wedges.
Comparison of Quadratic‐ and Median‐Based Roughness Penalties for Penalized‐Likelihood Sinogram Restoration in Computed Tomography
Authors: La Rivière Patrick J. , Bian Junguo , Vargas Phillip A.
Published: April 2006

We have compared the performance of two different penalty choices for a penalized‐likelihood sinogram‐restoration strategy we have been developing. One is a quadratic penalty we have employed previously and the other is a new median‐based penalty. We compared the approaches to a noniterative adaptive filter that loosely but not explicitly models data statistics. We found that the two approaches produced similar resolution‐variance tradeoffs to each other and that they outperformed the adaptive filter in the low‐dose regime, which suggests that the particular choice of penalty in our approach may be less important than the fact that we are explicitly modeling data statistics at all. Since the quadratic penalty allows for derivation of an algorithm that is guaranteed to monotonically increase the penalized‐likelihood objective function, we find it to be preferable to the median‐based penalty.
A Multiresolution PDE‐Based Deformable Surface for Medical Imaging Applications
Authors: Duan Ye
Published: April 2006

We recently developed a multiresolution PDE‐based deformable surface whose deformation behavior is governed by partial differential equations (PDEs) such as the weighted minimal surface flow. Comparing with the level‐set approach, our new model has better control of the mesh quality and model resolution, and is much simpler to implement since all the computations are local. The new deformable model is very useful for a variety of medical imaging applications including boundary reconstruction, surface visualization, data segmentation, and topology discovery. In this paper, we demonstrate both the accuracy and robustness of our model on areas such as medical image segmentation through a number of experiments on both real (MRI/CT) and synthetic volumetric datasets.
Stability of invariant sets of Itô stochastic differential equations with Markovian switching
Authors: Luo Jiaowan
Published: April 2006

Consider the nonlinear Itô stochastic differential equations
with Markovian switching, some sufficient conditions for the
invariance, stochastic stability, stochastic asymptotic stability,
and instability of invariant sets of the equations are derived.
A semimartingale characterization of average optimal stationary policies for Markov decision processes
Authors: Zhu Quanxin , Guo Xianping
Published: April 2006

This paper deals with discrete‐time Markov decision processes with
Borel state and action spaces. The criterion to be minimized is
the average expected costs, and the costs may have neither
upper nor lower bounds. In our former paper (to appear in Journal
of Applied Probability), weaker conditions are proposed
to ensure the existence of average optimal stationary policies. In
this paper, we further study some properties of optimal policies.
Under these weaker conditions, we not only obtain two
necessary and sufficient conditions for optimal policies, but also
give a “semimartingale characterization” of an average optimal
stationary policy.
Nitric Oxide Levels in Patients with Psoriasis Treated with Methotrexate
Authors: Tekin Nilgun Solak , Ilter Nilsel , Sancak Banu , Ozden Muge Guler , Gurer Mehmet Ali
Published: April 2006

Psoriasis is a chronic, recurrent, inflammatory, and hyperproliferative disease. Recently there have been studies regarding increases in the levels of NO in inflammatory dermatoses including psoriasis. In this study, 22 patients with psoriasis were scored with PASI (psoriasis area and severity index) and the levels of serum nitrite‐nitrate were evaluated before and after therapy with methotrexate (Mtx). The results were compared with age‐ and sex‐matched healthy volunteers. The relation of the results with the clinical severity and the cumulative Mtx dose were also evaluated. The serum levels of nitrite‐nitrate of the psoriatic patients with active lesions were
found to be significantly higher than the levels of the healthy volunteers and the patients after therapy. The elevated
nitrite‐nitrate serum levels in the inflammatory period may suggest the possible role of this mediator in the etiopathogenesis of psoriasis and the potential future use of NO inhibitors in the treatment of psoriasis.
Regulated Spatial Distribution of Cyclooxygenases and Lipoxygenases in Crohn′s Ulcer
Authors: Mao Yao , Ren Jian′an , Li Jieshou
Published: April 2006

Background and Aims. Arachidonic acid metabolism actively participates in the initiation, climaxing, and resolution phases of inflammation, and its close connection with inflammatory bowel diseases has been only recently discovered. We aimed to clarify the role of different arachidonic pathways and the interrelationships between them in Crohn′s disease. Methods. Seventeen specimens of Crohn′s disease dated between 2003/1/1 and 2005/1/1 were collected and underwent immunohistochemical analyses with cylcooxygenase 1, cyclooxygenase 2, 5‐lipoxygenase, and 15‐lipoxygenase‐1 antibodies. Results. (1) The spatial distribution of the three leading enzymes in arachidonic acid pathway—cyclooxygenase 2, 5‐lipoxygenase, and 15‐lipoxygenase‐1—followed sequential arrangement in Crohn′s ulcer: neutrophils highly expressing 5‐lipoxygenase were in the utmost surface which bordered the band of cyclooxygenase‐2 expression that is located just beneath it, and in the lower layers and below the granulation region were eosinophils carrying 15‐lipoxygeanse‐1. (2) Cyclooxygenase‐2 and 15‐Lipoxygenase‐1‐positive cells formed two barrier‐like structures that possibly inhibited neutrophil infiltration. Conclusion. The regulated distribution indicated coordinated interplay between inflammatory cells and parenchymal cells, between arachidonic acid pathways, and between innate and adaptive immunity; and the barrier‐like structures indicated protective roles for cyclooxygenase 2 and 15‐Lipoxygenase‐1 in Crohn′s disease.
Negotiating the uncomfortable intersections between gender and professional identities in social work
Authors: Christie Alastair
Published: April 2006

This article is based on a study of men’s relationship to the social work profession in the North-West of England. It argues that men’s presence in the social work profession is accounted for in discourses of career motivation, of career choice, and of men social workers as heroes and/or ‘gentle-men’. The article considers how these negotiations between gender and professional identities might contribute to debates about the detraditionalization of gender and work identities in late modernity.
Decline in pre-school use in post-socialist societies: the case of Bulgaria
Authors: Meurs Mieke , Giddings Lisa
Published: April 2006

Child care is often analysed in its role as facilitator of women's labour-force participation. However, for pre-school-aged children, child care can also contribute in important ways to human-capital development, especially among poor children. By international standards, pre-school enrolments were high under socialism. Since transition, however, enrolment rates have declined. This may leave large numbers of children without the preparation necessary to succeed in school and to be included in the region's post-socialist development. We examine the changing dynamics of preschool enrolment in Bulgaria. We evaluate demand and supply-side explanations for changing enrolments and use municipal-level data to develop a simple model of demand. We examine the impact of changing employment and earnings, proximity and perceived quality of child-care centres, as well as ethnic/cultural background. Through this model, we hope to broaden understanding of preschool enrolment decisions, and to assist policymakers in improving pre-school attendance.
Talking Divorce: The Role of Divorce in Women's Constructions of Relationship Status
Authors: Sandfield Anna
Published: April 2006

This article draws on interviews discussing relationships with 25 heterosexual women aged 20–87 from a variety of relationship status groups. Divorce was portrayed as a negative consequence of flawed individual skills and investments, reinforcing the marriage ideal and obscuring any advantages of this transition for the increasing numbers facing single-again life. Those interviewees who had been divorced did not endorse these attributions and negotiated their social lives around feedback from others employing these interpretations. The ways in which discourses of divorce reinforce dominant marital models of heterosexual relationships are examined alongside the implications of this for the growing population of single-again women.
International Politics of Insecurity: Normativity, Inwardness and the Exception
Authors: Huysmans Jef
Published: April 2006

This article seeks (a) to show the complexities of the concept of exception in international politics, (b) to suggest that the current politics of insecurity are not limited to a clash over the status and limits of normativity in international politics, and (c) to introduce conceptual groundwork for theorizing international politics of insecurity as a contest of the exception. By combining normative and existential concepts of exception, a conceptual matrix is introduced that distinguishes between political liberalism and realism, on the one hand, and anti-diplomatic ultrapolitical realism and liberalism, on the other. While the focus in discussions of exception is often on the tension between realist assertions of the limited validity of international norms and liberal assertions of the real capacity of international norms to constrain political power, something more complex may be going on in current international politics of insecurity. The conceptual matrix draws attention to an additional tension between those realists and liberals willing to retain common grounds for symbolic mediation in international politics and those seeking to intensify antidiplomatic inwardness.
Creeping Unilateralism: How Operation Provide Comfort and the No-Fly Zones in 1991 and 1992 Paved the Way for the Iraq Crisis of 2003
Authors: Cockayne James , Malone David
Published: April 2006

In this article, it is argued that the genesis of the Iraq Crisis of 2003 within the Security Council can be traced to earlier patterns of acquiescence by Council members in US and UK unilateral enforcement action in Iraq. By the time this acquiescence ceased, between 1994 and 1996, UK and US enforcement policy was set and would culminate in Operation Iraqi Freedom in March 2003.
When Soft Power Turns Hard: Is an EU Strategic Culture Possible?
Authors: Matlary Janne Haaland
Published: April 2006

Posing the question of whether the European Union is likely to develop a strategic culture, this article discusses the concept of human security as the possible basis for a novel type of such a culture. It argues that there are incentives for governments to ‘pool’ sovereignty in the security and defence field on the logic of two-level games, while noting that EU institutions themselves are developing both political and military capacities at present. The sensitive issue of developing a strategic culture for coercive diplomacy and the consequent use of force is not progressing. However, the ideological basis for a post-national strategic culture based on human security provides a window of opportunity for the EU.
Isothermal Fatigue Damage Model for Lead-free Solder
Authors: Wei Yong , Chow C. L. , Vianco Paul , Fang Eliot
Published: April 2006

This article presents an investigation of lead-free solder material 95.5Sn-3.9Ag-0.6Cu under isothermal fatigue loading. The effects of strain rate on hysteresis loop and fatigue life over the total strain range from 0.4 to 1% at room temperature are investigated. A fatigue damage model is established to characterize the isothermal fatigue behavior of the material with the theory of damage mechanics. A fatigue failure criterion is proposed based on the concept of damage accumulation in solder material. The model takes into account the effect of strain rate in the development of constitutive and damage evolution equations. The life prediction is compared with the testing data and has shown a good agreement.
Modeling Transverse Behavior of Kevlar® KM2 Single Fibers with Deformation-induced Damage
Authors: Cheng Ming , Chen Weinong
Published: April 2006

A phenomenological continuum model is adapted to describe the transverse mechanical behavior of Kevlar® KM2 single fibers in compression. This model could be used for numerical simulations of the mechanical behaviors of fabrics made of Kevlar® KM2 fibers. An equivalent fiber model is used to form the phenomenological model in terms of nominal stress and nominal stretch ratio. This model includes the features of stress-softening and residual strain to account for the damage caused by transverse compression, making it more accurate to represent the fiber when the effects of physical crossover of warp and fill yarns are considered and multiple loadings are applied. It is demonstrated that this model provides a good agreement with experimental results on the transverse behavior of Kevlar® KM2 single fibers in compression.
A Numerical Study of the Size and Rate Effects on the Mechanical Response of Single Crystal Diamond and UNCD Films
Authors: Shen Luming , Chen Zhen
Published: April 2006

To better understand the mechanical response of ultrananocrystalline diamond (UNCD) and its grain boundary mechanism, a numerical study is performed of the specimen size and rate effects on the mechanical properties of single crystal diamond and UNCD films under uniaxial and shear loading paths, respectively. To compare with the UNCD films, single crystal diamond blocks of various sizes under tensile loading in the 100 hi direction and shear loading with the {100} 110 hi slip at different rates are first investigated via the molecular dynamics (MD) simulation. A combined kinetic Monte Carlo (KMC) and MD procedure is then developed for large-scale atomistic simulation of the mechanical response of UNCD films. In this numerical procedure, two single crystal diamond films, that are formed by the KMC method based on the mechanisms of UNCD growth from carbon dimers on the hydrogen-free (001) surface, are compressed along the [001] direction with two growth surfaces contacting each other at an elevated temperature in the MD simulation to create a polycrystalline UNCD film with certain grain boundary. The mechanical response of the resulting UNCD film is investigated by applying displacement-controlled shear loading in the MD simulation, and is compared with that of single crystal diamond. The preliminary results presented in this article provide a better understanding of the size and rate effects on the material properties of diamond and the role played by the grain boundary on influencing the mechanical response of UNCD films.