Size Greater (size + greater)

Distribution by Scientific Domains


Selected Abstracts


Risk factors related to traumatic dental injuries in Brazilian schoolchildren

DENTAL TRAUMATOLOGY, Issue 5 2004
Evelyne Pessoa Soriano
Abstract,,, The aim of this pilot study was to analyse whether overjet, lip coverage and obesity represented risk factors associated with the occurrence of dental trauma in the permanent anterior teeth of schoolchildren in Recife, Brazil. It included a random sample of 116 boys and girls aged 12 years, attending both public and private schools. Data was collected through clinical examinations and interviews. Dental trauma was classified according to Andreasen's criteria (1994). Overjet was considered as risk factor when it presented values higher than 5 mm. Lip coverage was classified as adequate or inadequate, while obesity was considered according to National Center for Health Statistics (NCHS) procedures for the assessment of nutritional status. The prevalence of dental injuries was 23.3%. Boys experienced more injuries than girls, 30 and 16.1%, respectively (P > 0.05). There was a statistically significant difference between traumatic dental injuries and overjet (P < 0.05) and between traumatic dental injuries and lip coverage (P = 0.000). No statistical significant differences were found when obesity and dental trauma were analysed (P < 0.05). It was concluded that boys from lower social strata attending public schools, presenting an overjet size greater than 5 mm and an inadequate lip coverage, were more likely to have traumatic dental injuries in Recife, Brazil. Obesity was not a risk factor for dental trauma in this sample. [source]


Sibship analysis of associations between SNP haplotypes and a continuous trait with application to mammographic density

GENETIC EPIDEMIOLOGY, Issue 4 2010
J. Stone
Abstract Haplotype-based association studies have been proposed as a powerful comprehensive approach to identify causal genetic variation underlying complex diseases. Data comparisons within families offer the additional advantage of dealing naturally with complex sources of noise, confounding and population stratification. Two problems encountered when investigating associations between haplotypes and a continuous trait using data from sibships are (i) the need to define within-sibship comparisons for sibships of size greater than two and (ii) the difficulty of resolving the joint distribution of haplotype pairs within sibships in the absence of parental genotypes. We therefore propose first a method of orthogonal transformation of both outcomes and exposures that allow the decomposition of between- and within-sibship regression effects when sibship size is greater than two. We conducted a simulation study, which confirmed analysis using all members of a sibship is statistically more powerful than methods based on cross-sectional analysis or using subsets of sib-pairs. Second, we propose a simple permutation approach to avoid errors of inference due to the within-sibship correlation of any errors in haplotype assignment. These methods were applied to investigate the association between mammographic density (MD), a continuously distributed and heritable risk factor for breast cancer, and single nucleotide polymorphisms (SNPs) and haplotypes from the VDR gene using data from a study of 430 twins and sisters. We found evidence of association between MD and a 4-SNP VDR haplotype. In conclusion, our proposed method retains the benefits of the between- and within-pair analysis for pairs of siblings and can be implemented in standard software. Genet. Epidemiol. 34: 309,318, 2010. © 2009 Wiley-Liss, Inc. [source]


Propranolol plus placebo versus propranolol plus isosorbide-5-mononitrate in the prevention of a first variceal bleed: A double-blind RCT

HEPATOLOGY, Issue 6 2003
Juan Carlos García-Pagán M.D.
Nonselective ,-blockers are very effective in preventing first variceal bleeding in patients with cirrhosis. Treatment with isosorbide-5-mononitrate (IS-MN) plus propranolol achieves a greater reduction in portal pressure than propranolol alone. The present multicenter, prospective, double-blind, randomized, controlled trial evaluated whether combined drug therapy could be more effective than propranolol alone in preventing variceal bleeding. A total of 349 consecutive cirrhotic patients with gastroesophageal varices were randomized to receive propranolol + placebo (n = 174) or propranolol + IS-MN (n = 175). There were no significant differences in the 1- and 2-year actuarial probability of variceal bleeding between the 2 groups (propranolol + placebo, 8.3% and 10.6%; propranolol + IS-MN, 5% and 12.5%). The only independent predictor of variceal bleeding was a variceal size greater than 5 mm. However, among patients with varices greater than 5 mm (n = 196), there were no significant differences in the incidence of variceal bleeding between the 2 groups. Survival was also similar. Adverse effects were significantly more frequent in the propranolol + IS-MN group due to a greater incidence of headache. There were no significant differences in the incidence of new-onset or worsening ascites or in impairment of renal function. In conclusion, propranolol effectively prevents variceal bleeding. Adding IS-MN does not further decrease the low residual risk of bleeding in patients receiving propranolol. However, the long-term use of this combination drug therapy is safe and may be an alternative in clinical conditions associated with a greater risk of bleeding. [source]


Liver transplantation for hepatocellular carcinoma: Analysis of survival according to the intention-to-treat principle and dropout from the waiting list

LIVER TRANSPLANTATION, Issue 10 2002
Francis Y. Yao MD
A major obstacle for orthotopic liver transplantation (OLT) as treatment for hepatocellular carcinoma (HCC) is tumor growth resulting in dropout from the waiting list for OLT. There is a paucity of data on survival according to intention-to-treat analysis and the rate of dropout from the waiting list for OLT among patients with HCC. To further evaluate these issues, we analyzed the outcome of 46 consecutive patients with HCC listed for OLT between January 1998 and January 2001. Exclusion criteria for OLT were tumor size greater than 5 cm for one to three lesions or four lesions or greater of any size. Twenty-one patients underwent OLT. There were 11 dropouts because of tumor progression and six deaths, including three deaths after dropout. Kaplan-Meier 1- and 2-year intention-to-treat survival rates were 91.7% and 72.6%, respectively. Monthly dropout rates were 0% from 0 to 3 months, 1.5% from 3 to 6 months, 1.0% from 6 to 9 months, 4.9% from 9 to 12 months, and 5.6% from 12 to 15 months. One dropout occurred beyond 15 months among 4 patients remaining at risk. Cumulative probabilities for dropout at 6, 12, and 24 months were 7.3%, 25.3%, and 43.6%, respectively. Predictors for dropout included two or three tumor nodules or a solitary lesion greater than 3 cm at initial presentation and previous hepatic resection. Our results support recent changes in the scheme of organ allocation aimed at reducing the dropout rate and improving outcome for patients with HCC awaiting OLT. [source]


Precision cosmology with voids: definition, methods, dynamics

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 3 2010
Guilhem Lavaux
ABSTRACT We propose a new definition of cosmic voids based on methods of Lagrangian orbit reconstruction as well as an algorithm to find them in actual data called DynamIcal Void Analysis. Our technique is intended to yield results which can be modelled sufficiently accurately to create a new probe of precision cosmology. We then develop an analytical model of the ellipticity of voids found by our method based on the Zel'dovich approximation. We measure in N -body simulation that this model is precise at the ,0.1 per cent level for the mean ellipticity of voids of size greater than ,4 h,1 Mpc. We estimate that at this scale we are able to predict the ellipticity with an accuracy of ,,, 0.02. Finally, we compare the distribution of void shapes in N -body simulation for two different equations of state w of the dark energy. We conclude that our method is far more accurate than Eulerian methods and is therefore promising as a precision probe of dark energy phenomenology. [source]


On the power of BFS to determine a graph's diameter,

NETWORKS: AN INTERNATIONAL JOURNAL, Issue 4 2003
Derek G. Corneil
Abstract Recently, considerable effort has been spent on showing that Lexicographic Breadth First Search (LBFS) can be used to determine a tight bound on the diameter of graphs from various restricted classes. In this paper, we show that, in some cases, the full power of LBFS is not required and that other variations of Breadth First Search (BFS) suffice. The restricted graph classes that are amenable to this approach all have a small constant upper bound on the maximum-sized cycle that may appear as an induced subgraph. We show that, on graphs that have no induced cycle of size greater than k, BFS finds an estimate of the diameter that is no worse than diam(G) , ,k/2,. © 2003 Wiley Periodicals, Inc. [source]


Macular hole surgery with and without internal limiting membrane peeling

ACTA OPHTHALMOLOGICA, Issue 2009
C KOURENTIS
Purpose To compare the results of surgery for idiopathic macular hole with or without the surgical removal of the internal limiting membrane (ILM) and the effect on anatomical and functional success rates. Methods 41 consecutive patients with idiopathic macular hole stage II (n=11), III (n=22) and IV (n=8) underwent pars plana vitrectomy and intraocular gas tamponade in this study. The surgery was performed either with ILM peeling,Group A (n=28), or without, Group B (n=13). Ocular coherence tomography and ETDRS visual acuity were measured pre- and postoperatively to assess macular hole size and anatomical hole closure as well as visual function. Results The postoperative macular hole closure rate was 100% (28/28) in Group A and 84,6% (11/13) in Group B. The 2 cases that failed to close with primary surgery had a hole size greater than 400µm. There was no significant difference between the two groups in the postoperative visual outcome once anatomical success was achieved. Conclusion The study suggests that more evidence based trials are necessary to investigate the benefit of ILM peeling especially in the treatment of larger macular holes. [source]


Minimizing makespan on a single batch processing machine with nonidentical job sizes

NAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 3 2001
Guochuan Zhang
Abstract We deal with the problem of minimizing makespan on a single batch processing machine. In this problem, each job has both processing time and size (capacity requirement). The batch processing machine can process a number of jobs simultaneously as long as the total size of these jobs being processed does not exceed the machine capacity. The processing time of a batch is just the processing time of the longest job in the batch. An approximation algorithm with worst-case ratio 3/2 is given for the version where the processing times of large jobs (with sizes greater than 1/2) are not less than those of small jobs (with sizes not greater than 1/2). This result is the best possible unless P = NP. For the general case, we propose an approximation algorithm with worst-case ratio 7/4. A number of heuristics by Uzosy are also analyzed and compared. © 2001 John Wiley & Sons, Inc. Naval Research Logistics 48: 226,240, 2001 [source]