340 research outputs found
On nonlinear susceptibility in supercooled liquids
In this paper, we discuss theoretically the behavior of the four point
nonlinear susceptibility and its associated correlation length for supercooled
liquids close to the Mode Coupling instability temperature . We work in
the theoretical framework of the glass transition as described by mean field
theory of disordered systems, and the hypernetted chain approximation. Our
results give an interpretation framework for recent numerical findings on
heterogeneities in supercooled liquid dynamics.Comment: Proceedings of the Conference "Unifying Concepts in Glass Physics"
ICTP, Trieste, 15 - 18 September 199
Present and Future CP Measurements
We review theoretical and experimental results on CP violation summarizing
the discussions in the working group on CP violation at the UK phenomenology
workshop 2000 in Durham.Comment: 104 pages, Latex, to appear in Journal of Physics
Authors' reply re: Wide differences in mode of delivery within Europe: risk-stratified analyses of aggregated routine data from the Euro-Peristat study
To access publisher's full text version of this article click on the hyperlink at the bottom of the pageTo use data from routine sources to compare rates of obstetric intervention in Europe both overall and for subgroups at higher risk of intervention.Retrospective analysis of aggregated routine data.Thirty-one European countries or regions contributing data on mode of delivery to the Euro-Peristat project.Births in participating countries in 2010.Countries provided aggregated data about overall rates of obstetric intervention and about caesarean section rates for specified subgroups.Mode of delivery.Rates of caesarean section ranged from 14.8% to 52.2% of all births and rates of instrumental vaginal delivery ranged from 0.5% to 16.4%. Overall, there was no association between rates of instrumental vaginal delivery and rates of caesarean section, but similarities were observed between some countries that are geographically close and may share common traditions of practice. Associations were observed between caesarean section rates for women with breech and vertex births and with singleton and multiple births but patterns of association for women who had and had not had previous caesarean sections were more complex.The persisting wide variations in caesarean section and instrumental vaginal delivery rates point to a lack of consensus about practice and raise questions for further investigation. Further research is needed to explore the impact of differences in clinical guidelines, healthcare systems and their financing and parents' and professionals' attitudes to care at delivery.info:eu-repo/grantAgreement/EC/FP7/2010130
Predictors of early recurrence after resection of colorectal liver metastases
BACKGROUND: Early recurrence after resection of colorectal liver metastases (CLM) is common. Patients at risk of early recurrence may be candidates for enhanced preoperative staging and/or earlier postoperative imaging. The aim of this study was to determine if there are any risk factors that specifically predict early liver-only and systemic recurrence. METHODS: Retrospective analysis of prospective database of patients undergoing liver resection (LR) for CLM from 2004 to 2006 was undertaken. Early recurrence was defined as occurring within 18Β months of LR. Patients were classified into three groups: early liver-only recurrence, early systemic recurrence and recurrence-free. Preoperative factors were compared between patients with and without early recurrence. RESULTS: Two hundred and forty-three consecutive patients underwent LR for CLM. Twenty-seven patients (11%) developed early liver-only recurrence. Dukes C stage and male sex were significantly associated with early liver-only recurrence (Pβ<β0.05). Sixty-six patients (27%) developed early systemic recurrence. Tumour size β₯3.6Β cm and tumour number (>2) were significantly associated with early systemic recurrence (Pβ<β0.001). CONCLUSIONS: It is possible to stratify patients according to the risk of early liver-only or systemic recurrence after resection of CLM. High-risk patients may be candidates for preoperative MRI and/or computed tomography-positron emission tomography (CT-PET) scan and should receive intensive postoperative surveillance
Does bathymetry drive coastal whale shark (Rhincodon typus) aggregations?
Background
The whale shark (Rhincodon typus) is known to aggregate in a number of coastal locations globally, however what causes these aggregations to form where they do is largely unknown. This study examines whether bathymetry is an important driver of coastal aggregation locations for R. typus through bathymetryβs effect on primary productivity and prey availability. This is a global study taking into account all coastal areas within R. typusβ range.
Methods
R. typus aggregation locations were identified through an extensive literature review. Global bathymetric data were compared at R. typus aggregation locations and a large random selection of non-aggregation areas. Generalised linear models were used to assess which bathymetric characteristic had the biggest influence on aggregation presence.
Results
Aggregation sites were significantly shallower than non-aggregation sites and in closer proximity to deep water (the mesopelagic zone) by two orders of magnitude. Slope at aggregation sites was significantly steeper than non-aggregation sites. These three bathymetric variables were shown to have the biggest association with aggregation sites, with up to 88% of deviation explained by the GLMs.
Discussion
The three key bathymetric characteristics similar at the aggregation sites are known to induce upwelling events, increase primary productivity and consequently attract numerous other filter feeding species. The location of aggregation sites in these key areas can be attributed to this increased prey availability, thought to be the main reason R. typus aggregations occur, extensively outlined in the literature. The proximity of aggregations to shallow areas such as reefs could also be an important factor why whale sharks thermoregulate after deep dives to feed. These findings increase our understanding of whale shark behaviour and may help guide the identification and conservation of further aggregation sites
Association of predicted 10Β years cardiovascular mortality risk with duration of HIV infection and antiretroviral therapy amongΒ HIV-infected individualsΒ in Durban, South Africa
Background: South Africa has the largest population of human immunodeficiency virus (HIV) infected patients on antiretroviral therapy (ART) realising the benefits of increased life expectancy. However, this population may be susceptible to cardiovascular disease (CVD) development, due to the chronic consequences of a lifestyle-related combination of risk factors, HIV infection and ART. We predicted a 10-year cardiovascular mortality risk in an HIV-infected population on long-term ART, based on their observed metabolic risk factor profile. Methods: We extracted data from hospital medical charts for 384 randomly selected HIV-infected patients aged β₯β30 years. We defined metabolic syndrome (MetS) subcomponents using the International Diabetes Federation definition. A validated non-laboratory-based model for predicting a 10-year CVD mortality risk was applied and categorised into five levels, with the thresholds ranging from very low-risk (β30%). Results: Among the 384 patients, with a mean (Β± standard deviation) age of 42.90βΒ±β8.20 years, the proportion of patients that were overweight/obese was 53.3%, where 50.9% had low high-density lipoprotein (HDL) cholesterol and 21 (17.5%) had metabolic syndrome. A total of 144 patients with complete data allowed a definitive prediction of a 10-year CVD mortality risk. 52% (95% CI 44-60) of the patients were stratified to very low risk (β30%) of 10-year CVD mortality. The CVD risk grows with increasing age (years), 57.82βΒ±β6.27 among very high risk and 37.52βΒ±β4.50; pβ<β0.001 in very low risk patients. Adjusting for age and analysing CVD risk mortality as a continuous risk score, increasing duration of HIV infection (pβ=β0.002) and ART (pβ=β0.007) were significantly associated with increased predicted 10 year CVD mortality risk. However, there was no association between these factors and categorised CVD mortality risk as per recommended scoring thresholds. Conclusions: Approximately 1 in 10 HIV-infected patients is at very high risk of predicted 10-year CVD mortality in our study population. Like uninfected individuals, our study found increased age as a major predictor of 10-year mortality risk and high prevalence of metabolic syndrome. Additional CVD mortality risk due to the duration of HIV infection and ART was seen in our population, further studies in larger and more representative study samples are encouraged. It recommends an urgent need for early planning, prevention and management of metabolic risk factors in HIV populations, at the point of ART initiation
Genetic determinants in a critical domain of ns5a correlate with hepatocellular carcinoma in cirrhotic patients infected with hcv genotype 1b
HCV is an important cause of hepatocellular carcinoma (HCC). HCV NS5A domainβ1 interacts with cellular proteins inducing proβoncogenic pathways. Thus, we explore genetic variations in NS5A domainβ1 and their association with HCC, by analyzing 188 NS5A sequences from HCV genotypeβ1b infected DAAβnaΓ―ve cirrhotic patients: 34 with HCC and 154 without HCC. Specific NS5A mutations significantly correlate with HCC: S3T (8.8% vs. 1.3%, p = 0.01), T122M (8.8% vs. 0.0%, p < 0.001), M133I (20.6% vs. 3.9%, p < 0.001), and Q181E (11.8% vs. 0.6%, p < 0.001). By multivariable analysis, the presence of >1 of them independently correlates with HCC (OR (95%CI): 21.8 (5.7β82.3); p < 0.001). Focusing on HCCβgroup, the presence of these mutations correlates with higher viremia (median (IQR): 5.7 (5.4β6.2) log IU/mL vs. 5.3 (4.4β5.6) log IU/mL, p = 0.02) and lower ALT (35 (30β71) vs. 83 (48β108) U/L, p = 0.004), suggesting a role in enhancing viral fitness without affecting necroinflammation. Notably, these mutations reside in NS5A regions known to interact with cellular proteins crucial for cellβcycle regulation (p53, p85βPIK3, and Ξ²β catenin), and introduce additional phosphorylation sites, a phenomenon known to ameliorate NS5A interaction with cellular proteins. Overall, these results provide a focus for further investigations on molecular bases of HCVβmediated oncogenesis. The role of these NS5A domainβ1 mutations in triggering proβoncogenic stimuli that can persist also despite achievement of sustained virological response deserves further investigation
Measurement of using pairs from bosons produced in collisions at a center-of-momentum energy of 1.96 TeV
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