University of Crete

About: University of Crete is a education organization based out in Rethymno, Greece. It is known for research contribution in the topics: Population & Galaxy. The organization has 8681 authors who have published 21684 publications receiving 709078 citations. The organization is also known as: Panepistimio Kritis.

The structure of the free boundary for lower dimensional obstacle problems

Abstract: We study the regularity of the "free surface" in boundary obstacle problems. We show that near a non-degenerate point the free boundary is a C^1,a (n - 2)-dimensional surface in R^n-1.

The effects of Crocus sativus (saffron) and its constituents on nervous system: A review

Abstract: Saffron or Crocus sativus L. (C. sativus) has been widely used as a medicinal plant to promote human health, especially in Asia. The main components of saffron are crocin, picrocrocin and safranal. The median lethal doses (LD50) of C. sativus are 200 mg/ml and 20.7 g/kg in vitro and in animal studies, respectively. Saffron has been suggested to be effective in the treatment of a wide range of disorders including coronary artery diseases, hypertension, stomach disorders, dysmenorrhea and learning and memory impairments. In addition, different studies have indicated that saffron has anti-inflammatory, anti-atherosclerotic, antigenotoxic and cytotoxic activities. Antitussive effects of stigmas and petals of C. sativus and its components, safranal and crocin have also been demonstrated. The anticonvulsant and anti-Alzheimer properties of saffron extract were shown in human and animal studies. The efficacy of C. sativus in the treatment of mild to moderate depression was also reported in clinical trial. Administration of C. sativus and its constituents increased glutamate and dopamine levels in the brain in a dose-dependent manner. It also interacts with the opioid system to reduce withdrawal syndrome. Therefore, in the present article, the effects of C. sativus and its constituents on the nervous system and the possible underlying mechanisms are reviewed. Our literature review showed that C. sativus and its components can be considered as promising agents in the treatment of nervous system disorders.

Autophagy Controls BCG-Induced Trained Immunity and the Response to Intravesical BCG Therapy for Bladder Cancer

Abstract: The anti-tuberculosis-vaccine Bacillus Calmette-Guerin (BCG) is the most widely used vaccine in the world. In addition to its effects against tuberculosis, BCG vaccination also induces non-specific beneficial effects against certain forms of malignancy and against infections with unrelated pathogens. It has been recently proposed that the non-specific effects of BCG are mediated through epigenetic reprogramming of monocytes, a process called trained immunity. In the present study we demonstrate that autophagy contributes to trained immunity induced by BCG. Pharmacologic inhibition of autophagy blocked trained immunity induced in vitro by stimuli such as b-glucans or BCG. Single nucleotide polymorphisms (SNPs) in the autophagy genes ATG2B (rs3759601) and ATG5 (rs2245214) influenced both the in vitro and in vivo training effect of BCG upon restimulation with unrelated bacterial or fungal stimuli. Furthermore, pharmacologic or genetic inhibition of autophagy blocked epigenetic reprogramming of monocytes at the level of H3K4 trimethylation. Finally, we demonstrate that rs3759601 in ATG2B correlates with progression and recurrence of bladder cancer after BCG intravesical instillation therapy. These findings identify a key role of autophagy for the nonspecific protective effects of BCG.

Gain-driven discrete breathers in PT-symmetric nonlinear metamaterials.

Abstract: We introduce a one-dimensional parity-time- ($\mathcal{P}\mathcal{T}$-)symmetric nonlinear magnetic metamaterial consisting of split-ring dimers having both gain and loss. When nonlinearity is absent we find a transition between an exact to a broken $\mathcal{P}\mathcal{T}$ phase; in the former, the system features a two band gapped spectrum with shape determined by the gain and loss coefficients as well as the interunit coupling. In the presence of nonlinearity, we show numerically that as a result of the gain and dissipation matching a novel type of long-lived stable discrete breathers can form below the lower branch of the band with no attenuation. In these localized modes the energy is almost equally partitioned between two adjacent split rings on the one with gain and the other one with loss.