Indefinite almost paracontact metric manifolds

In this paper we introduce the concept of $(\varepsilon)$-almost paracontact manifolds, and in particular, of $(\varepsilon)$-para Sasakian manifolds. Several examples are presented. Some typical identities for curvature tensor and Ricci tensor of $(\varepsilon)$-para Sasakian manifolds are obtained. We prove that if a semi-Riemannian manifold is one of flat, proper recurrent or proper Ricci-recurrent, then it can not admit an $(\varepsilon)$-para Sasakian structure. We show that, for an $(\varepsilon)$-para Sasakian manifold, the conditions of being symmetric, semi-symmetric or of constant sectional curvature are all identical. It is shown that a symmetric spacelike (resp. timelike) $(\varepsilon)$-para Sasakian manifold $M^{n}$ is locally isometric to a pseudohyperbolic space $H_{\nu}^{n}(1)$ (resp. pseudosphere $S_{\nu}^{n}(1)$). In last, it is proved that for an $(\varepsilon)$-para Sasakian manifold, the conditions of being Ricci-semisymmetric, Ricci-symmetric and Einstein are all identical

Plasma levels of vitamin B12, epidermal growth factor and tumor necrosis factor alpha in patients with alzheimer dementia

Background: It was previously reported that vitamin B12 (Vit B12) has the regulatory effects on epidermal growth factor (EGF) and tumor necrosis factor alpha (TNF-α). The role of Vit B12, EGF and TNF-α in the pathogenesis of alzheimer dementia has not been elucidated yet. In this study the plasma Vit B12, EGF and TNF-α level were examined in individuals, between 65-99 years old with and without alzheimer dementia (AD).  Methods: The study group comprised 47 patients with AD and 38 cases without dementia. EGF and TNF-α were analyzed by ELISA, and Vit B12 was analyzed by chemiluminescence method.Results: Vit B12 and EGF levels were significantly lower (p<0.0001), whereas TNF-α levels were significantly higher (p<0.0001) in the AD group in comparison to those without AD.  Conclusions: Our results suggest that Vit B12, EGF and TNF-α may have a role in the pathophysiology of AD.

Analysis of Suprapubic and Transrectal Measurements in Assessment of Prostate Dimensions and Volume: Is Transrectal Ultrasonography Really Necessary for Prostate Measurements?

&lt;p&gt;&lt;strong&gt;Introduction:&lt;/strong&gt; The objective of this study was to evaluate the correlation of suprapubic ultrasonography and transrectal ultrasonography in measurements of prostate dimension and volume.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materials and Methods: &lt;/strong&gt;One hundred consecutive patients with lower urinary tract symptoms were examined by suprapubic and transrectal ultrasonography modalities in a same session. Measurements of the 3 dimensions of the prostate (anteroposterior, transverse, and craniocaudal) and its volume performed by suprapubic ultrasonography were compared with the corresponding measurements by transrectal ultrasonography in order to determine the correlation of the measurements. Prostate volumes were calculated using the ellipsoid formula. Data were further analyzed in subgroups according to prostate volumes smaller or larger than 50 mL, measured by suprapubic ultrasonography.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results:&lt;/strong&gt; The mean prostate volume of the 100 patients, measured by suprapubic and transrectal ultrasonography were 65.9 ± 35.8 mL and 62.5 ± 32.0 mL, respectively (r = 0.94; P &lt; .001). The craniocaudal diameters had the strongest correlation among dimension measurements (r = 0.89; P &lt; .001). Suprapubic and transrectal ultrasonography measurements also showed significant correlations for both prostates smaller or larger than 50 mL. Eighty-five percent of the patients had both volume measurements under or above this limit.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion:&lt;/strong&gt; There was strong correlation between suprapubic and transrectal ultrasonography measurements of the prostate sizes, including both for volume or specific dimension measurements.&lt;/p&gt

Prediction of second neurological attack in patients with clinically isolated syndrome using support vector machines

The aim of this study is to predict the conversion from clinically isolated syndrome to clinically definite multiple sclerosis using support vector machines. The two groups of converters and non-converters are classified using features that were calculated from baseline data of 73 patients. The data consists of standard magnetic resonance images, binary lesion masks, and clinical and demographic information. 15 features were calculated and all combinations of them were iteratively tested for their predictive capacity using polynomial kernels and radial basis functions with leave-one-out cross-validation. The accuracy of this prediction is up to 86.4% with a sensitivity and specificity in the same range indicating that this is a feasible approach for the prediction of a second clinical attack in patients with clinically isolated syndromes, and that the chosen features are appropriate. The two features gender and location of onset lesions have been used in all feature combinations leading to a high accuracy suggesting that they are highly predictive. However, it is necessary to add supporting features to maximise the accuracy. © 2013 IEEE

Some optimal inequalities for screen conformal half-lightlike submanifolds

In this paper, some relations involving the main intrinsic and extrinsic invariants for a half-lightlike submanifold of a Lorentzian manifold are given. Some results for screen conformal half-lightlike submanifolds and their leaves are obtained with the help of these relations

On the developable ruled surfaces Kinematically generated in Minkowski 3-Space

In this paper, we present a method to be developable of a ruled surface, generated in Minkowski 3-space R corresponding to the dual Lorentzian curves according to E. Study's transference principle and some theorems and examples.</p