Effect of a realistic three-body force on the spectra of medium-mass hypernuclei

We adopt the Hartree-Fock (HF) method in the proton-neutron-$\Lambda$ (p-n-$\Lambda$) formalism and the nucleon-$\Lambda$ Tamm-Dancoff Approximation (N$\Lambda$ TDA) to study the energy spectra of medium-mass hypernuclei. The formalism is developed for a potential derived from effective field theories which includes explicitly the 3-body $NNN$ forces plus the $YN$ LO potential. The energy spectra of selected medium-mass hypernuclei are presented and their properties discussed. The present calculation is the first step of a project devoted to {\it ab initio} studies of hypernuclei in medium and heavy mass regions. This may provide a guide for a better understanding of the $YN$ interactions at momentum scales not accessible in few-body hypernuclei.Comment: 7 pages, 9 figures, accepted in Physica Script

Collagen orientation and waviness within the vein wall

This paper presents the analysis of the internal structure and organization of components within the vein wall. Dominant directions and statistical distribution of collagen fibers undulation were investigated in digitalized histological sections from media and adventitia layer of human vena cava inferior. Orientations of collagen fibers were analyzed by the in-house developed software Binary Directions. Digital images were converted to binary pixel maps with collagen fibers enhanced. The software employs an algorithm of the Rotation Line Segment to determine significant directions in digital images. It was found that collagen fibers are aligned in circumferential direction in media layer. Contrary to that in adventitia fibers are arranged in longitudinal direction. In contrast to elastic artery, no evidence of helically reinforced composite structure was found. Second goal was to find out which statistical distribution, usually using in structural models (Gamma, Beta or Weibull), fits to the undulation distribution of collagen fibers. Collagen waviness was characterized by a probability density function for the strain necessary to straighten a crimped fiber. Computer analysis of the end-to-end and contour length was performed using Nis-Elements software. The statistical analysis suggests that the waviness of collagen fibers is identical in media and adventitia It was found that the average strain necessary for straightening collagen fibers is 0.24±0.11 (±SD) and that all three probability distributions fit straightening strains very well and can be used in structural model

EFFECT OF STERILIZATION ON MECHANICAL PROPERTIES OF COLLAGEN-BASED COMPOSITE TUBES

In this study, composite tubes were manufactured from biological collagenous matrix and reinforcing polyester mesh. The effect of sterilization on mechanical properties of this structure was evaluated using inflation-extension tests. Samples were exposed to two types of sterilization (ethylene oxide and gamma irradiation). The control (non-sterilized) samples were also tested. The closed thick walled tube model was used in order to compute stresses within sterilized and control specimens. It was found that the process of sterilization (especially irradiation) dramatically affects the final mechanical properties of the material. These findings should be taken into account when such collagenous material is assumed to be used in tissue engineering

Model-Based Security Testing

Security testing aims at validating software system requirements related to security properties like confidentiality, integrity, authentication, authorization, availability, and non-repudiation. Although security testing techniques are available for many years, there has been little approaches that allow for specification of test cases at a higher level of abstraction, for enabling guidance on test identification and specification as well as for automated test generation. Model-based security testing (MBST) is a relatively new field and especially dedicated to the systematic and efficient specification and documentation of security test objectives, security test cases and test suites, as well as to their automated or semi-automated generation. In particular, the combination of security modelling and test generation approaches is still a challenge in research and of high interest for industrial applications. MBST includes e.g. security functional testing, model-based fuzzing, risk- and threat-oriented testing, and the usage of security test patterns. This paper provides a survey on MBST techniques and the related models as well as samples of new methods and tools that are under development in the European ITEA2-project DIAMONDS.Comment: In Proceedings MBT 2012, arXiv:1202.582

Opening angle of human saphenous vein

In this study, the residual strain was evaluated for human saphenous vein. Rings of the vein from four donors (two male and two female; age 62±5 years) were radially cut to obtain the opening angle (α) of the tissue. It was found that the average opening angle (α) 45°±18° (mean±SD). Then, the intraluminal distribution of circumferential stress was computed for one donor in order to verify the uniform stress hypothesis (opening angle is homogenizing the stress distribution across the wall thickness). The results suggests that α obtained from experiments is close to the value of opening angle which homogenizes the stress distribution across the wall thickness determined from simulations

Biomechanical Testing of Spinal Segment Fixed by Arcofix System on the Swine Spine

Study DesignAn in vitro biomechanical study.PurposeTo evaluate the mechanical properties of the spinal segment in the intact, injured, and stabilized state after fixation by an Arcofix implant.Overview of LiteratureSeveral types of thoracolumbar spine injury necessitates anterior instrumentation. The Arcofix plate represents the latest generation of angular stablity systems. The biomechanical properties of these implants have not been sufficiently studied yet.MethodsA total of ten porcine specimens (levels Th12-L3) were prepared. The tests were performed for intact, injured, and implanted specimens. In each state, the specimen was subjected to a tension load of a prescribed force, and subsequently, twisted by a given angle. The force load was 200 N. The torsion load had a deformation character, i.e., the control variable was the twisting angle and the measured variable was the moment of a couple. The amplitude of the load alternating cycle was 3°. Another parameter that was evaluated was the area of the hysteresis loop. The area corresponds to the deformation energy which is dissipated during the cycle.ResultsA statistically significant difference was found between the intact and injured states as well as between the injured and implanted specimens. The statistical evaluation also showed a statistically different value of the hysteresis loop area. In the case of instability, the area decreased to 33% of the physiological value. For the implanted sample, the area increased to 170% of the physiological value.ConclusionsThe Arcofix implant with its parameters appears to be suitable and sufficiently stable for the treatment of the anterior column of the spine

Novel benzoxaborole, nitroimidazole and aminopyrazoles with activity against experimental cutaneous leishmaniasis.

OBJECTIVES: Drugs for Neglected Diseases initiative (DNDi) has identified three chemical lead series, the nitroimidazoles, benzoxaboroles and aminopyrazoles, as innovative treatments for visceral leishmaniasis. The leads discovered using phenotypic screening, were optimised following disease- and compound-specific criteria. Several leads of each series were progressed and preclinical drug candidates have been nominated. Here we evaluate the efficacy of the lead compounds of each of these three chemical classes in in vitro and in vivo models of cutaneous leishmaniasis. METHODS: The in vitro activity of fifty-five compounds was evaluated against the intracellular amastigotes of L. major, L. aethiopica, L. amazonensis, L. panamensis, L. mexicana and L. tropica. The drugs demonstrating potent activity (EC50 < 5 μM) against at least 4 of 6 species were subsequently evaluated in vivo in different L. major - BALB/c mouse models using a 5 or 10-day treatment with either the oral or topical formulations. Efficacy was expressed as lesion size (measured daily using callipers), parasite load (by quantitative PCR - DNA) and bioluminescence signal reduction relative to the untreated controls. RESULTS: The selected drug compounds (3 nitroimidazoles, 1 benzoxaborole and 3 aminopyrazoles) showed consistent and potent activity across a range of Leishmania species that are known to cause CL with EC50 values ranging from 0.29 to 18.3 μM. In all cases, this potent in vitro antileishmanial activity translated into high levels of efficacy with a linear dose-response against murine CL. When administered at 50 mg/kg/day, DNDI-0690 (nitroimidazole), DNDI-1047 (aminopyrazole) and DNDI-6148 (benzoxaborole) all resulted in a significant lesion size reduction (no visible nodule) and an approximate 2-log-fold reduction of the parasite load as measured by qPCR compared to the untreated control. CONCLUSIONS: The lead compounds DNDI-0690, DNDI-1047 and DNDI-6148 showed excellent activity across a range of Leishmania species in vitro and against L. major in mice. These compounds offer novel potential drugs for the treatment of CL

Mapping of hormones and cortisol responses in patients after Lyme neuroborreliosis

<p>Abstract</p> <p>Background</p> <p>Persistent symptoms after treatment for neuroborreliosis are common for reasons mainly unknown. These symptoms are often unspecific and could be caused by dysfunctions in endocrine systems, an issue that has not been previously addressed systematically. We therefore mapped hormone levels in patients with previous confirmed Lyme neuroborreliosis of different outcomes and compared them with a healthy control group.</p> <p>Methods</p> <p>Twenty patients of a retrospective cohort of patients treated for definite Lyme neuroborreliosis were recruited 2.3 to 3.7 years (median 2.7) after diagnosis, together with 23 healthy controls. Lyme neuroborreliosis patients were stratified into two groups according to a symptom/sign score. All participants underwent anthropometric and physiological investigation as well as an extensive biochemical endocrine investigation including a short high-dose adrenocorticotropic hormone stimulation (Synacthen^®) test. In addition to hormonal status, we also examined electrolytes, 25-hydroxy-vitamin D and interleukin-6.</p> <p>Results</p> <p>Eight patients (40%) had pronounced symptoms 2-3 years after treatment. This group had a higher cortisol response to synacthen as compared with both controls and the Lyme neuroborreliosis patients without remaining symptoms (p < 0.001 for both comparisons). No other significant differences in the various baseline biochemical parameters, anthropometric or physiological data could be detected across groups.</p> <p>Conclusions</p> <p>Apart from a positive association between the occurrence of long-lasting complaints after Lyme neuroborreliosis and cortisol response to synacthen, no corticotropic insufficiency or other serious hormonal dysfunction was found to be associated with remaining symptoms after treatment for Lyme neuroborreliosis.</p