Frequently hypercyclic semigroups

We study frequent hypercyclicity in the context of strongly continuous semigroups of operators. More precisely, we give a criterion (sufficient condition) for a semigroup to be frequently hypercyclic, whose formulation depends on the Pettis integral. This criterion can be verified in certain cases in terms of the infinitesimal generator of semigroup. Applications are given for semigroups generated by Ornstein-Uhlenbeck operators, and especially for translation semigroups on weighted spaces of $p$-integrable functions, or continuous functions that, multiplied by the weight, vanish at infinity

Generalized Gaussian Estimates for Elliptic Operators with Unbounded Coefficients on Domains

We consider second-order elliptic operators A in divergence form with coefficients belonging to Lloc∞(Ω), when Ω ⊆ ℝd is a sufficiently smooth (unbounded) domain. We prove that the realization of A in L2(Ω), with Neumann-type boundary conditions, generates a contractive, strongly continuous and analytic semigroup (T(t)) which has a kernel k satisfying generalized Gaussian estimates, written in terms of a distance function induced by the diffusion matrix and the potential term. Examples of operators where such a distance function is equivalent to the Euclidean one are also provided

On vector-valued Schrödinger operators with unbounded diffusion in Lp spaces

We prove generation results of analytic strongly continuous semigroups on Lp(Rd, Rm) (1 < p< ∞) for a class of vector-valued Schrödinger operators with unbounded coefficients. We also prove Gaussian type estimates for such semigroups

Decreasing initial telomere length in humans intergenerationally understates age-associated telomere shortening

Telomere length shortens with aging, and short telomeres have been linked to a wide variety of pathologies. Previous studies suggested a discrepancy in age-associated telomere shortening rate estimated by cross-sectional studies versus the rate measured in longitudinal studies, indicating a potential bias in cross-sectional estimates. Intergenerational changes in initial telomere length, such as that predicted by the previously described effect of a father's age at birth of his offspring (FAB), could explain the discrepancy in shortening rate measurements. We evaluated whether changes occur in initial telomere length over multiple generations in three large datasets and identified paternal birth year (PBY) as a variable that reconciles the difference between longitudinal and cross-sectional measurements. We also clarify the association between FAB and offspring telomere length, demonstrating that this effect is substantially larger than reported in the past. These results indicate the presence of a downward secular trend in telomere length at birth over generational time with potential public health implications

Postvaccination Influenza 2009 H1N1 Respiratory Failure Requiring Extracorporeal Membrane Oxygenation

The spread of pandemic Influenza A (H1N1-2009) was believed to have been attenuated by the effectiveness of worldwide vaccination initiatives. Despite the immunogenicity of a safe vaccine, we report a case of vaccine failure resulting in catastrophic influenza-associated respiratory failure

Pelvic floor function after third and fourth degree perineal lacerations: a case-control study on quality of life

Background: The primary aim of this study was to compare the quality of life between women with obstetric anal sphincter injury (OASI) and women with intact perineum or minor vaginal tears following their first vaginal birth through a validated urogynaecological questionnaire. As a secondary aim, we wanted to identify the specific symptoms for pelvic floor dysfunction after a vaginal birth. Methods: One hundred thirty-three cases (III- and IV-degree vaginal tears) and 133 controls (intact perineum or I- and II-degree vaginal tear) were asked to fill the PFDI-20 condition-specific and quality of life survey at three and 12 months after vaginal delivery. The survey evaluates pelvic floor dysfunction symptoms through three subsections: the Pelvic Organ Prolapse Distress Inventory (POPDI), the Colorectal-Anal Distress Inventory (CRADI), and Urinary Distress Inventory, (UDI). The scoring system ranges from 0 (no distress) to 100 (maximum distress) for each subsection, subsequently summed up to obtain the summary score (0 to 300). The patients recruited were asked to complete the survey at 3- and 12-months follow-up visit. Accordingly, data collection started. Categorical variables were subjected to Chi-square test or Fisher’s Exact test. Quantitative variables were compared through Student’s t-test or Mann-Whitney test. Results: All surveys have shown statistically significant differences when comparing the cases to the control group. Consequently, PFDI-20 has shown a strong correlation between III- and IV-grade lacerations and pelvic floor dysfunction persistence at 12 months after delivery. Intestinal symptoms were the most reported disturbances among women with previous OASI. Conclusions: Major vaginal tears have demonstrated to have a strong impact on women’s quality of life up to a follow-up of 12 months. The use of PFDI-20 questionnaire is a useful and valid tool in the diagnosis and follow-up of genital prolapse, fecal and urinary incontinence in primiparous women with a history of OASI. Thus, its application in clinical practice can help offering the most adequate rehabilitative treatment

Data-driven curation, learning and analysis for inferring evolving IoT botnets in the wild

The insecurity of the Internet-of-Things (IoT) paradigm continues to wreak havoc in consumer and critical infrastructure realms. Several challenges impede addressing IoT security at large, including, the lack of IoT-centric data that can be collected, analyzed and correlated, due to the highly heterogeneous nature of such devices and their widespread deployments in Internet-wide environments. To this end, this paper explores macroscopic, passive empirical data to shed light on this evolving threat phenomena. This not only aims at classifying and inferring Internet-scale compromised IoT devices by solely observing such one-way network traffic, but also endeavors to uncover, track and report on orchestrated "in the wild" IoT botnets. Initially, to prepare the effective utilization of such data, a novel probabilistic model is designed and developed to cleanse such traffic from noise samples (i.e., misconfiguration traffic). Subsequently, several shallow and deep learning models are evaluated to ultimately design and develop a multi-window convolution neural network trained on active and passive measurements to accurately identify compromised IoT devices. Consequently, to infer orchestrated and unsolicited activities that have been generated by well-coordinated IoT botnets, hierarchical agglomerative clustering is deployed by scrutinizing a set of innovative and efficient network feature sets. By analyzing 3.6 TB of recent darknet traffic, the proposed approach uncovers a momentous 440,000 compromised IoT devices and generates evidence-based artifacts related to 350 IoT botnets. While some of these detected botnets refer to previously documented campaigns such as the Hide and Seek, Hajime and Fbot, other events illustrate evolving threats such as those with cryptojacking capabilities and those that are targeting industrial control system communication and control services

Dietary influence on systolic and diastolic blood pressure in the TwinsUK cohort

Nutrition plays a key role in blood pressure (BP) regulation. Here, we examine associations between nutrient intakes and BP in a large predominantly female population-based cohort. We assessed the correlation between 45 nutrients (from food frequency questionnaires) and systolic BP/diastolic BP (SBP/DBP) in 3889 individuals from TwinsUK not on hypertensive treatments and replicated in an independent subset of monozygotic twins discordant for nutrient intake (17–242 pairs). Results from both analyses were meta-analysed. For significant nutrients, we calculated heritability using structural equation modelling. We identified and replicated 15 nutrients associated with SBP, 9 also being associated with DBP, adjusting for covariates and multiple testing. 14 of those had a heritable component (h2: 27.1–57.6%). Strong associations with SBP were observed for riboflavin (Beta(SE) = −1.49(0.38), P = 1.00 × 10−4) and tryptophan (−0.31(0.01), P = 5 × 10−4), while with DBP for alcohol (0.05(0.07), P = 1.00 × 10−4) and lactose (−0.05(0.0), P = 1.3 × 10−3). Two multivariable nutrient scores, combining independently SBP/DBP-associated nutrients, explained 22% of the variance in SBP and 13.6% of the variance in DBP. Moreover, bivariate heritability analysis suggested that nutrients and BP share some genetic influences. We confirm current understanding and extend the panel of dietary nutrients implicated in BP regulation underscoring the value of nutrient focused dietary research in preventing and managing hypertension