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Milnor open books of links of some rational surface singularities
No full textWe determine Legendrian surgery diagrams for the canonical contact structures of links of rational surface singularities that are also small Seifert fibered 3-manifolds. Moreover, we describe an infinite family of Milnor fillable contact 3-manifolds so that, for each member of this family, the Milnor genus and Milnor norm are strictly greater than the support genus and support norm of the canonical contact structure. For some of these contact structures we construct supporting Milnor open books
Main conjectures for CM fields and a Yager-type theorem for Rubin-Stark elements
No full textIn this article, we study the p-ordinary Iwasawa theory of the (conjectural) Rubin–Stark elements defined over abelian extensions of a CM field F and develop a rank-g Euler–Kolyvagin system machinery (where Graphic), refining and generalizing Perrin-Riou's theory and the author's prior work. This has several important arithmetic consequences: using the recent results of Hida and Hsieh on the CM main conjectures, we prove a natural extension of a theorem of Yager for the CM field F, where we relate the Rubin–Stark elements to the several-variable Katz p-adic L-function. Furthermore, beyond the cases covered by Hida and Hsieh, we are able to reduce the p-ordinary CM main conjectures to a local statement about the Rubin–Stark elements. We discuss applications of our results in the arithmetic of CM abelian varieties
Conspicuity of peripheral zone prostate cancer on computed diffusion-weighted imaging: comparison of cDWI(1500), cDWI(2000), and cDWI(3000)
No full textIntroduction and Objective. Disadvantages associated with direct high b-value measurements may be avoided with use of computed diffusion-weighted imaging (cDWI). The purpose of this study is to assess the diagnostic performance of cDWI image sets calculated for high b-values of 1500, 2000, and 3000 s/mm(2). Materials and Methods. Twenty-eight patients who underwent multiparametric MRI of the prostate and radical prostatectomy consecutively were enrolled in this retrospective study. Using a software developed at our institute, cDWI 1500, cDWI 2000, and cDWI 3000 image sets were generated by fitting a monoexponential model. Index lesions on cDWI image sets were scored by two radiologists in consensus considering lesion conspicuity, suppression of background prostate tissue, distortion, image set preferability, and contrast ratio measurements were performed. Results. Lesion detection rates are the same for computed b-values of 2000 and 3000 s/ mm 2 and are better than b-values of 1500 s/ mm(2). Best lesion conspicuity and best background prostate tissue suppression are provided by cDWI(3000) image set. cDWI(2000) image set provides the best zonal anatomical delineation and less distortion and was chosen as the most preferred image set. Average contrast ratio measured on these image sets shows almost a linear relation with the b-values. Conclusion. cDWI 2000 image set with similar conspicuity and the same lesion detection rate, but better zonal anatomical delineation, and less distortion, was chosen as the preferable image set
Area minimizing surfaces in mean convex 3-manifolds
No full textIn this paper, we give several results on area minimizing surfaces in strictly mean convex 3-manifolds. First, we study the genus of absolutely area minimizing surfaces in a compact, orientable, strictly mean convex 3-manifold M bounded by a simple closed curve in partial derivative M. Our main result is that for any g >= 0, the space of simple closed curves in partial derivative M where all the absolutely area minimizing surfaces they bound in M has genus >= g is open and dense in the space A of nullhomologous simple closed curves in partial derivative M. For showing this we prove a bridge principle for absolutely area minimizing surfaces. Moreover, we show that for any g >= 0, there exists a curve gamma(g) in A such that the minimum genus of the absolutely area minimizing surfaces gamma(g) bounds is exactly g. As an application of these results, we further prove that the simple closed curves in partial derivative M bounding more than one minimal surface in M is an open and dense subset of A. We also show that there are disjoint simple closed curves in partial derivative M bounding minimal surfaces in M which are not disjoint. This allows us to answer a question of Meeks, by showing that for any strictly mean convex 3-manifold M, there exists a simple closed curve Gamma in partial derivative M which bounds a stable minimal surface which is not embedded. We also gave some applications of these results to the simple closed curves in R-3
Differential DNA methylation of genes involved in fibrosis progression in non-alcoholic fatty liver disease and alcoholic liver disease.
No full textBackground: Chronic liver injury can lead to the development of liver fibrosis and cirrhosis but only in a minority of patients. Currently, it is not clear which factors determine progression to fibrosis. We investigated whether DNA\methylation profile as determined by pyrosequencing can distinguish patients with mild from those with advanced/severe fibrosis in non-alcoholic liver disease (NAFLD) and alcoholic liver disease (ALD). To this end, paraffin-embedded liverbiopsies were collected from patients with biopsy-proven NAFLD or ALD, as well as paraffin-embedded normal liver resections, genomic DNA isolated, bisulfite converted and pyrosequencing assays used to quantify DNA methylation at specific CpGs within PPAR alpha, PPAR alpha, TGF beta 1, Collagen 1A1 and PDGF alpha genes. Furthermore, we assessed the impact of age, gender and anatomical location within the liver on patterns of DNA methylation inthe same panel of genes. Results: DNA methylation at specific CpGs within genes known to affect fibrogenesis distinguishes between patients with mild from those with severe fibrosisin both NAFLD and ALD, although same CpGs are not equally represented in both etiologies. In normal liver, age, gender or anatomical location had no significant impact on DNA methylation patterns in the liver. Conclusions: DNA methylation status at specific CpGs may be useful as part of a wider set of patient data for predicting progression to liver fibrosis
Outcomes of resections for pancreatic adenocarcinoma with suspected venous involvement: a single center experience.
No full textBackground: Pancreatic ductal adenocarcinoma (PDAC) patients frequently present with borderline resectable disease, which can be due to invasion of the portal/superior mesenteric vein (PV/SMV). Here, we analyzed this group of patients, with emphasis on short and long-term outcomes. Methods: 156 patients who underwent a resection for PDAC were included in the analysis and sub-stratified into a cohort of patients with PV/SMV resection (n = 54) versus those with standard surgeries (n = 102). Results: While venous resections could be performed safely, there was a trend towards shorter median survival in the PV/SMV resection group (22.7 vs. 15.8 months, p = 0.157). These tumors were significantly larger (3.5 vs 4.3 cm; p = 0.026) and margin-positivity was more frequent (30.4 % vs 44.4 %, p = 0.046). Conclusion: Venous resection was associated with a higher rate of margin positivity and a trend towards shorter survival. However, compared to non-surgical treatment, resection offers the best chance for long term survival
Radiological anatomy of the C7 vertebra: clinical implications in spine surgery
No full textContext: This study was designed to understand and define the special radio-anatomic morphometry of C7 vertebra by using multidetector computed tomography (MDCT). Aims: The major aim of the study was to detect the gender- and side-related morphometric differences of C7 vertebra among subjects. Setting and design: Our radiology unit database scanned for MDCT sections of the C7 vertebra. Materials and Methods: A total of 214 patients (134 men, 80 women) were selected. A detailed morphometric evaluation of C7 was done. Statistical analysis used: T test, ANOVA. Lamina length (P < 0.001), pedicle length (P < 0.001), outer cortical (P = 0.01) and inner cancellous pedicle (P < 0.001) width, pedicle angle to sagittal plane (P < 0.001) values were statistically significantly different on the right versus left side. When the results were stratified by gender, lamina length, inner cancellous lamina height, pedicle length, inner cancellous pedicle height, outer cortical pedicle width, lateral mass anteroposterior length, anteroposterior length of C7 corpus, height of C7 corpus (P < 0.001), C6-7 (P = 0.013) and C7-T1disc height (P = 0.04), transverse foramina perpendicular width at C7 (P = 0.046) values were found to be statistically significantly different. Vertebral artery most commonly enters into the transverse foramina at C6 level. Conclusions: Gender and side differences are important factors for preoperative planning and showed significant differences among subjects. MDCT is a practical option for investigating the exact anatomical features of osseous structures
Editorial: Representational states in memory: where do we stand?
No full textThis editorial discusses representational states in memory. For decades researchers have assessed the interactions and dissociations across memory systems and representational states using behavioral investigations, seeking for the key principles that govern them. Recent advances in neuroscience have provided the field with a new set of tools that can be employed to complement and extend previous efforts by means of assessing the corresponding underlying neural mechanisms. In an effort to move toward a more unified perspective, this research topic brought together a collection of empirical, theoretical and review articles that collectively advance our understanding of representational states in memory, as well as bear the potential to reconcile some of the differences across the models. The authors conclude by highlighting several venues for future research. Recent advances in neuroscience now enable powerful approaches that combine behavioral indices along with complementary neuroscience methods that can utilize univariate and multivariate analyses of neuroimaging data on healthy individuals, as well as transcranial magnetic stimulation and lesion studies to test and infer similarities and dissociations across the hypothesized states of memory. (PsycINFO Database Record (c) 2015 APA, all rights reserved
Bulgarmaden inscription
No full textBlack and white image of Bulgarmaden rock inscription which is carved on a rock cliff near the Madenköy village (also known as Bolkar Maden, Bulgarmaden) of Adana. This hieroglyphic Luwian inscription is about 400 meters above the road and five-line inscription expands to an area of 1.5 meter by 1.3 meter. It is dated to the second half of the 8th century BC. It mentions the Hittite ruler Tarhunaza who was a vassal of King Warpalawa of Tuwana. According to the text, Tarhunaza received the Mount Muti (possibly ancient name of Bolkar Mountain) as a gift from Warpalawa, and Tarhunaza offers his appreciation to him and the gods.135 film (36×24 mm
Bulgarmaden inscription
No full textBlack and white image of Bulgarmaden rock inscription which is carved on a rock cliff near the Madenköy village (also known as Bolkar Maden, Bulgarmaden) of Adana. This hieroglyphic Luwian inscription is about 400 meters above the road and five-line inscription expands to an area of 1.5 meter by 1.3 meter. It is dated to the second half of the 8th century BC. It mentions the Hittite ruler Tarhunaza who was a vassal of King Warpalawa of Tuwana. According to the text, Tarhunaza received the Mount Muti (possibly ancient name of Bolkar Mountain) as a gift from Warpalawa, and Tarhunaza offers his appreciation to him and the gods.135 film (36×24 mm