Constructing optimal entanglement witnesses. II

We provide a class of optimal nondecomposable entanglement witnesses for 4N x 4N composite quantum systems or, equivalently, a new construction of nondecomposable positive maps in the algebra of 4N x 4N complex matrices. This construction provides natural generalization of the Robertson map. It is shown that their structural physical approximations give rise to entanglement breaking channels.Comment: 6 page

The role of the Amyloid Precursor Protein mutations and PERK-dependent signaling pathways in the pathogenesis of Alzheimer’s disease

Alzheimer’s disease (AD) is a highly complex, progressive, age-related neurodegenerative human disease entity. The genetic basis of AD is strictly connected with occurrence of mutations in Amyloid Precursor (APP) gene on chromosome 21. Molecular mechanism that leads to AD development still remains unclear. Recent data reported that it is closely correlated with Endoplasmic Reticulum (ER) stress conditions, which subsequently activate Unfolded Protein Response (UPR) signaling pathways, via the induction of protein kinase RNA-like endoplasmic reticulum kinase (PERK), as a self-protective, adaptive response to adverse stress conditions. That results in the attenuation of global protein synthesis and, on the contrary, selective translation of Activating Transcriptor Factor 4 (ATF4) and secretase β. Interestingly, under prolonged, severe ER stress UPR may switch its signal into apoptotic cell death. That ensues by ATF4-CHOP-mediated activation of a range of pro-apoptotic genes and, on the other hand, downregulation of the expression of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) genes. Current investigations suggest that inhibitions of PERK activity may contribute to the attenuation of the deposition of toxic senile plaques in the brain tissue and, as a result, prevent degeneration of neurons and decline in cognitive abilities

Artificial Neural Network as a FPGA Trigger for a Detection of Neutrino-Induced Air Showers

Neutrinos play a fundamental role in the understanding of the origin of ultrahigh-energy cosmic rays (UHECR). They interact through charged and neutral currents in the atmosphere generating extensive air showers. However, the very low rate of events potentially generated by neutrinos is a significant challenge for detection techniques and requires both sophisticated algorithms and high-resolution hardware. We developed the FPGA trigger which is generated by a neural network. The algorithm can recognize various waveform types. It has been developed and tested on ADC traces of the Pierre Auger surface detectors. We developed the algorithm of artificial neural network on a MATLAB platform. Trained network that we implemented into the largest Cyclone V E FPGA was used for the prototype of the front-end board for the AugerPrime. We tested several variants, and the Levenberg–Marquardt algorithm (trainlm) was the most efficient. The network was trained: (a) to recognize ‘old’ very inclined showers (real Auger data were used as patterns for both positive and negative markers: for reconstructed inclined showers and for triggered by time over threshold (ToT), respectively, (b) to recognize ‘neutrino-induced showers’. Here, we used simulated data for positive markers and vertical real showers for negative ones.This work is supported by the National Science Centre (Poland) under NCN Grant No. 2013/08/ M/ST9/00322. The authors would like to thank the Pierre Auger Collaboration for an opportunity of using the CORSIKA and offline simulation packages

Constructing new optimal entanglement witnesses

We provide a new class of indecomposable entanglement witnesses. In 4 x 4 case it reproduces the well know Breuer-Hall witness. We prove that these new witnesses are optimal and atomic, i.e. they are able to detect the "weakest" quantum entanglement encoded into states with positive partial transposition (PPT). Equivalently, we provide a new construction of indecomposable atomic maps in the algebra of 2k x 2k complex matrices. It is shown that their structural physical approximations give rise to entanglement breaking channels. This result supports recent conjecture by Korbicz et. al.Comment: 9 page

Optimal entanglement witnesses from generalized reduction and Robertson maps

We provide a generalization of the reduction and Robertson positive maps in matrix algebras. They give rise to a new class of optimal entanglement witnesses. Their structural physical approximation is analyzed. As a byproduct we provide a new examples of PPT (Positive Partial Transpose) entangled states.Comment: 14 page

Clinical and neuropathological picture of ethylmalonic aciduria : diagnostic dilemma

Increased ethylmalonic acid (EMA) in urine is a non-specific finding, and is observed in a number of inborn errors of metabolism, as well as in individuals who carry one of two common polymorphisms identified in the SCAD coding region. The authors present an 8-month-old girl with a suspicion of neuroinfection, although the clinical presentation led to diagnosis of ethylmalonic aciduria. From the neuropathological point of view the most remarkable changes were observed in the brain cortex, which was diffusely damaged practically in all regions of the brain. Of note, the most severe destruction was observed in the deepest regions of the sulci. The cortex of the affected regions showed no normal stratification and its structure was almost totally replaced by a form of "granulation tissue" with a markedly increased number of capillaries. To the authors’ knowledge this is the first clinical report of ethylmalonic aciduria with brain autopsy findings

Enzymatic Characterization of ER Stress-Dependent Kinase, PERK, and Development of a High-Throughput Assay for Identification of PERK Inhibitors

PERK is serine/threonine kinase localized to the endoplasmic reticulum (ER) membrane. PERK is activated and contributes to cell survival in response to a variety of physiological stresses that affect protein quality control in the ER, such as hypoxia, glucose depravation, increased lipid biosynthesis, and increased protein translation. Pro-survival functions of PERK are triggered by such stresses, suggesting that development of small-molecule inhibitors of PERK may be efficacious in a variety of disease scenarios. Hence, we have conducted a detailed enzymatic characterization of the PERK kinase to develop a high-throughput-screening assay (HTS) that will permit the identification of small-molecule PERK inhibitors. In addition to establishing the Km of PERK for both its primary substrate, eIF2?, and for adenosine triphosphate, further mechanistic studies revealed that PERK targets its substrate via either a random/steady-state ordered mechanism. For HTS, we developed a time-resolved fluorescence resonance energy transfer–based assay that yielded a robust Z? factor and percent coefficient of variation value, enabling the successful screening of 79,552 compounds. This approach yielded one compound that exhibited good in vitro and cellular activity. These results demonstrate the validity of this screen and represent starting points for drug discovery efforts

Antibacterial, Anti-Inflammatory, Antioxidant, and Antiproliferative Properties of Essential Oils from Hairy and Normal Roots of Leonurus sibiricus

Essential oils obtained from the NR (normal roots) and HR (hairy roots) of the medicinal plant Leonurus sibiricus root were used in this study. The essential oil compositions were detected by GC-MS. Eighty-five components were identified in total. Seventy components were identified for NR essential oil. The major constituents in NR essential oil were β-selinene (9.9%), selina-4,7-diene (9.7%), (E)-β-caryophyllene (7.3%),myli-4(15)-ene (6.4%), and guaia-1(10),11-diene (5.9%). Sixty-seven components were identified in HR essential oil, the main constituents being (E)-β-caryophyllene (22.6%), and germacrene D (19.8%). The essential oils were tested for cytotoxic effect, antimicrobial, anti-inflammatory, and antioxidant activities. Both essential oils showed activity against grade IV glioma cell lines (IC50 = 400 μg/mL), antimicrobial (MIC and MFC values of 2500 to 125 μg/mL), and anti-inflammatory (decreased level of IL-1β, IL-6, TNF-α, and IFN-γ in LPS-stimulated cells).The essential oils exhibited moderate antioxidant activity in ABTS (EC50 = 98 and 88 μg/mL) assay. This is the first study to examine composition of the essential oils and their antimicrobial, antioxidant, antiproliferative, and anti-inflammatory activities. The results indicate that essential oils form L. sibiricus root may be used in future as an alternative to synthetic antimicrobial agents with potential application in the food and pharmaceutical industries

The dynamics of the surface layer of lipid membranes doped by vanadium complex: computer modeling and EPR studies

Penetration of the liposome membranes doped with vanadium complex formed in the liquid-crystalline phase from egg yolk lecithin (EYL) by the TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) spin probes has been investigated. The penetration process was followed by 360 hours at 24°C, using the electron spin resonance (EPR) method. The spectroscopic parameter of the partition (F) of this probe indicated that a maximum rigidity of the membrane was at 3% concentration of the vanadium complex. Computer simulations showed that the increase in the rigidity of the membrane corresponds to the closure of gaps in the surface layer of the membrane, and indicates the essential role of the membrane surface in transport processes