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Glycosphingolipids (GSLs) play numerous roles in cellular processes, including cell proliferation, apoptosis, inflammation, and cell signaling. Alteration of the GSLs metabolism leads to the accumulation of particular species of GSLs, which can lead to various pathologies, including carcinogenesis and metastasis; in essence, all neoplasms are characterized by the synthesis and aberrant organization of GSLs expressed on the cell surface. Secondary brain tumors make up the majority of intracranial cancers and generally present an unfavorable prognosis. In the present work, a native GSL mixture extracted and purified from a secondary brain tumor with primary pulmonary origin was obtained through extraction and purification and analyzed by MALDI TOF mass spectrometry. Research in the field of lipidomics could offer new data for the understanding of brain tropism and metastatic pathways, by studying the glycolipid molecules involved in the process of metastasis in general and in the production of brain metastases in particular. This could shed new light on the pattern of lipid glycosylation in secondary brain tumors, with a great impact on the effectiveness of cancer therapies, which could be adapted to the specific molecular pattern of the tumor.

An extensive literature exists regarding the cellular, physiological, and genetic effects of cadmium (Cd)—A highly toxic, but commonly used trace metal in modern industry. However, limited data are available on its epigenetic effects, especially for terrestrial sentinel invertebrates. We determined Cd retention, total DNA methylation, and the methylation status of 5′ end of the Cd-MT gene in the hepatopancreas of the brown garden snail, Cornu aspersum, fed Cd sulfate for four weeks. Bodyweight changes and survival were also measured. Hepatopancreas cadmium increased in a dose-dependent manner from the third-lowest dose onward, with very large amounts being found for the highest treatment group. However, no mortalities occurred, irrespective of dietary Cd dose. We identified significant genome-wide hypermethylation in specimens given the highest dose, which overlapped with a significant bodyweight decrease. The Cd-MT gene showed an unmethylated 5′ end of the Cd-MT gene and this status was not affected by cadmium exposure. Hepatopancreas DNA methylation is as sensitive as bodyweight to non-lethal concentrations of dietary Cd given as cadmium sulfate but less responsive than tissue accumulation. Such an exposure event, by contrast, does not affect the methylation status of the Cd-MT gene 5′ end.

The purpose of this study was to estimate Lyapunov exponents (LE) in order to quantify the local dynamic stability of the lower limb joints during sit-to-stand movement. The values of the Lyapunov exponents are obtained based on the experimental time series of the flexion-extension movements in sagittal plane and the rotational movements in frontal plane for all six main joints of both lower limbs, collected from a sample of healthy subjects and a sample of patients suffering by knee osteoarthritis before total knee replacement. The values of LEs obtained for the osteoarthritic lower limb are associated with more divergence and less stability, being generally, larger than those obtained for the other patient’ limb, and larger than those of healthy joints.

The aim of this study is to measure the variation of the flexion-extension angles of the knee and to study the stability of the knees movements during ascending and descending the stairs for healthy subjects and for patients suffering of osteoarthritic knee (OAK). Tools of nonlinear dynamics are used in order to quantify the stability of human healthy knee and OAK joints during ascending and descending the stairs. The values of Lyapunov exponents (LE), which represent the measure of instability of knee movements, are computed based on the experimental time series collected for both knee joints movements: flexion-extension (fl-ext) in sagittal plane and varus-valgus rotation (var-valg) in frontal plane. LEs obtained for the OAK are associated with more divergence, more variability and less stability, being larger than those are obtained for the knees of healthy subjects.

Metabolic therapy constitutes a relatively new therapeutic option for ischemic heart disease (IHD). Metabolic agents including Trimetazidine [1-(2,3,4-trimethoxybenzyl) piperazine] (TMZ) are currently used as anti-ischemic cardiac drugs to alleviate this internal metabolic disturbance. The present study focused on the assessment of the beneficial effects of TMZ as additional medication to the conventional medical therapy in patients with myocardial infarction. The obtained results showed an increase of superoxide dismutase (SOD) activities and a faster normalization of total sialic acid (TSA) levels in patients with TMZ add-on therapy, in comparison to the control group, indicating a stabilization of the ischemic process under TMZ therapy, with decreased free radical production and restoration of the antioxidant capacity and of the membrane lesions. The present findings emphasize the importance of TMZ administration to prevent reperfusion-mediated cardiac injury and dysfunction and demonstrate that this promising therapeutic approach is worthy of further research.

In this paper three types of actuation systems of active orthoses used for human gait rehabilitation are presented. This paper analyzes different lower-limb active orthoses used for gait rehabilitation function of actuation system.

In this paper finite-time Lyapunov exponents (LE) were estimated to quantify the local dynamic stability from the experimental time series of the flexion-extension angle of single subject knee joints, walking over-ground and on plane and inclined treadmill with different speeds and inclinations.

The first objective of this paper is to study the influence of a prosthesis on the maximum values of contact stresses developed in the components of the virtual model of a prosthetic knee assembly, using Finite element analysis (FEA). The second objective is to estimate Lyapunov exponents (LEs) in order to quantify the local dynamic stability of the human knee joint during walking overground for healthy subjects and for patients suffering of osteoarthritic knee (OAK), before and after total knee replacement (TKR), using tools of dynamics stability analysis. The values of the LEs are obtained based on the experimental time series of the flexion-extension movements in sagittal plane and the rotational movements in frontal plane for both knees, collected from a sample of healthy subjects and a sample of patients suffering by OAK before and after TKR. The influence of prosthesis mounted in OAK is positive, the values of LEs obtained for OAK four month after TKR are associated with increased stability, being smaller than those computed for OAK before TKR, and closer than those obtained for healthy knees.

The drive to prolong life and to improve life quality in patients suffering from cancer forms of any kind means that, aside from the necessary treatment, prognostic evaluations are needed. In our present study we included 63 patients with renal cell carcinoma. The histological samples obtained in surgery were studied through the classical histopathology methods, histochemical and immunohistochemical techniques. The histological degree of tumor differentiation was assessed for all cases, falling within all 4 classification grades. The immunohistochemical reaction for PCNA (proliferating cell nuclear antigen) was performed, utilizing the PC 10-LSAB antibody through visualization with the LSAB-DAB kit. This was the method used for assessing the process of tumor proliferation. Subsequently, the histological degree of differentiation was correlated with the PCNA score. We anticipate a reserved prognosis for patients with a positive expression on most tumor cells, which represents a high PCNA score.

In this paper finite-time Lyapunov exponents were estimated in order to quantify the local dynamic stability, based on the experimental time series of the flexion-extension and inversion-eversion angles of ankle joints, obtained from a group of five subjects with normal left ankles and right ankles suffering by repeated sprains with residual laxities walking over-ground and on plane and inclined treadmill with different speeds and inclinations.

Highlighting certain characteristics of T- and B-lymphocytes, as well as of vascular endothelial growth factor-A (VEGF-A) as a prognosis factors for patients suffering from acute pancreatitis, with the scope of establishing diagnosis and therapy.Pancreatic tissue samples were analyzed, originating from 21 patients deceased due to acute pancreatitis, between the years 2015 and 2016. The study group was subdivided into two subgroups by pathology duration. As control group, pancreatic tissue fragments were sampled from eight patients, deceased due to non-pancreatic acute surgical abdomen (NPASA).By analyzing the immunohistochemical expression of T-lymphocytes (immunomarked with the anti-CD3 antibody) and of B-lymphocytes (immunomarked with the anti-CD20 antibody), both on the tissue sections originating from the study patients, as well as the control group patients, we established that these were mostly present in the interstitium, following which the acini, less frequently in the islets, in general with B-lymphocytes being less present than T-lymphocytes. VEGF-A also tends to emerge in the acini periphery, at the border with the stromal connective tissue, while the islets are almost negative for VEGF-A.We can state that the decreased expression of T- and B-lymphocytes in normal pancreatic tissue, surrounding the necrosis areas, can be used as an aggravated prognosis factor for patients diagnosed with acute pancreatitis. Moreover, the increased immunohistochemical expression of VEGF-A can play an important role in tracking the evolution and pathology of acute pancreatitis.

During recent years, to solve as soon as possible the environment pollution problem, considerable improvements have been made in research and in international legislation. As research and manufacturing results are mentioned the new types of hybrid and electric vehicles and as legislation improvements have started to view carbon dioxide as a greenhouse gas that traps the earth’s heat and contributes to global warming. The present paper has, as a main target, the description of a modern and environmentally friendly solution regarding the dynamic control of an electric vehicle with traction induction motor. The dynamic control proposed by the author provides better traffic safety and an efficient management of electrical energy for the vehicle (reduced consumption by approximately 12 %).

Monotony is the result of continuous predictive or repetitive stimulations and can be considered a functional state of the central nervous system, a state characterized by lowered cerebral activity. The present work investigates the effect of monotonous auditory input on cerebral electrical activity. This was done by means of recording the EEG under three different auditory stimuli (S1, S2, S3), on 11 volunteers (average age 23 years). Data were acquisitioned during 20 minutes of auditory stimulation, with a 5 minute period of silence before and after stimulation. The characteristic features of each obtained EEG pattern depends closely on the type of the musical composition. Thus, the highest domain of variance generated under stimulation by S3 (fragments of the Mozart’s K448 Sonata) is for the frequency bands Alfa1, Beta2 and Theta, while in case of S2 (recording of a rainforest) it is for bands Delta, Beta1 and Alfa2, and in case of S1 (recording of a car driving over a rough road) is only slightly elevated for the total frequency spectrum. By comparing the period of auditory stimulation with the post-stimulation period, in case of S3 the fewest statistically significant mean values are noticeable (only for Delta and Theta indexes), in contrast to S1, which presents statistically significant differences between mean values for high frequency bands. In case of S2, statistically significant differences between mean values are similar to S3, with the addition of the Beta1 frequency band. In conclusion, each different auditory stimuli produces a characteristic pattern of changes in cortical micropotentials which could be associated with the induced psychoemotional state.

The objective of this study is to quantify and investigate nonlinear motion of the human knee joint for a sample of 7 healthy subjects on plane treadmill and inclined treadmill with an angle of 10° and for both knees of a sample of 3 patients who suffer of osteoarthritis, only on the plane treadmill, using nonlinear dynamics stability analysis. The largest Lyapunov exponent (LLE) and correlation dimensions are calculated as chaotic measures from the experimental time series of the flexion-extension angle of human knee joint. Larger values of LLEs obtained for patients group suffering by osteoarthritis are associated with more divergence and increase of knee variability, while smaller values obtained for healthy subjects reflect increase of local stability, less divergence and variability, less sensitivity to perturbations and higher resistance to stride-to-stride variability. The use of nonlinear tools may provide additional insight on the nature of the step-to-step fluctuations present in human and robotic locomotion.

The transition period which should have brought the end of the IPv4 era has no clear end in sight. With about 3% worldwide deployment rate, IPv6 still looks like a promise and the IPv6 transition like an ongoing struggle. Among the many challenges introduced by this transition process to the Internet community, one of the most difficult is to ensure a scalable network design when using IPv6 transition mechanisms. To that end, this article proposes a black-box approach for benchmarking the load scalability of IPv6 transition technologies. The tentative scalability metric quantifies the performance degradation of well-established metrics such as round-trip delay, jitter, throughput and packet loss. As a study case, empirical data for two open-source IPv6 transition implementations is presented.

We report the demonstration of robust, GaN-based hydrogen sensors for use directly in transformer oil. These 1 mm2 Schottky diodes were immersed in a closed loop with Voltesso insulating oil for 21 months of continuous testing. They showed good reproducibility in response to hydrogen gases, while exposed to varying temperatures. We will briefly discuss the transformer monitoring application, the device design and fabrication process, and the sensor performance from 21-months of testing. Transfer functions from oil temperature and dissolved gas concentration have been quantified, and those will be briefly discussed. These new sensors offer a novel alternative to electrochemical cell-based sensors for various applications. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

To have a suitable sustainability in large urban areas, a balance between resources, technology and environment must be provided. Thus, efforts to create new means of an environmentally friendly transport with performance and efficiency improved and with a reduced consumption of materials are opportune. Optimal operation and efficiency of electrical machines used as main vehicle propulsion sources are closed related to performance of soft and hard magnetic materials used to build them. Respecting this, new researches and developments are focused on new magnetic materials with superior performances, as rare earth based alloys ones. This paper presents theoretical and practical aspects regarding the magnetic material influence on electrical traction characteristics, taking into account the demagnetization process specific for permanent magnet (PM) traction motors. The demagnetization curves for NdFeB permanent magnets are obtained and their implications on optimal design of magnetic circuits of permanent magnet synchronous machines (PMSM) are analyzed. An assignment of two types of PM traction motors is effectuated taking into account their behavior related to the traction characteristics.

In the last years, because of pollution consequences within large urban areas, a growing interest appears in electric (EV) and hybrid vehicles (HEV) use. It demands for an efficient, reliable and economical motors and drives for electrical propulsion. A special research interest consists in searching and selecting for a suitable traction motor considering the vehicle architecture and dynamics. This paper investigates the main motor types for EV starting with dynamics and traction characteristics. Are presented extended speed range, working abilities and energy efficiency from vehicular system perspective. In this aim computer simulations and laboratory tests are accomplished. The combination between theoretical aspects, computer simulations and laboratory tests help to develop an easy selection of traction motors and drives dedicated to EV propulsion systems.

The purpose of the paper is analyzing the possibilities of improving the efficiency of a 2 kW wind pump storage system at low wind conditions. Two possible solutions are considered for the converter supplying the induction motor pump system: two-level and respectively three-level NPC inverter. Inverter total power losses are computed based on models proposed in the paper, considering a very low wind speed. Space vector pulse width modulation technique is used in both cases. Trench IGBT modules of 1200 V, respectively 600 V are considered as switches and 600 V SIC diode as clamping diode for the three-level NPC inverter.

Energy storage devices and solutions are required for power quality and balance within wind systems. In the context of rapidly expanding of distributed energy sources, the wind energy converters are in the center of interest. In this case, the direct dependence of the power generation capability for a given wind speed represents a major problem of wind energy conversion with regard to large-scale network integration. This paper proposes an overall solution which consists of a wind plant with a Smart Storage Modular System (SSMS) where the wind source -as stochastic one- is coupled over a dc bus with three storage modules and a smart grid interface. The investigated system consists of fours modules: a) the stochastic module (variable wind turbine with PMSG and ac/dc + bust converters), b) the short term storage module (flywheel with power electronic converter), c) the medium/long term module (Vanadium Redox Flow Battery with power electronic converter) and d) the medium term module (Lead Acid Battery). All of modules are interfaced with the network and insulated loads by a grid interface module (power electronic converter, filter and transformer). To the related SSMS, are accomplished computer simulations. In order to validate them, laboratory tests are also presented.

The evaluation of the efficacy of ursodeoxycholic acid (UDCA), pentoxifylline, losartan, and atorvastatin in non-alcoholic steatohepatitis (NASH) treatment.48 patients (25 males/23 females, aged 55 +/- 7.54 years) with histologically confirmed NASH were enrolled between 2001 and 2005. The batch was divided into four groups: A (10 dyslipidemic patients, receiving atorvastatin 10 mg/day), P (13 nonhypertensive/ nondyslipidemic patients receiving pentoxifylline 400 mg bid), L (12 hypertensive patients, treated with losartan, 50 mg/day) and U (13 nonhypertensive patients receiving UDCA 15 mg/kg/day). Mean duration of treatment was 37.8 +/- 5.4 weeks. Body mass index, liver biopsy and serum level of alanine-aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (AP), total cholesterol (TC) and triglycerides (TG) were determined at inclusion and at the end of treatment. Liver biopsy samples were evaluated for necroinflammation, steatosis and fibrosis (Brunt's score).In group A, a significant reduction of ALT, GGT, TC and AP was noticed. Histology showed diminished steatosis, but no improvement of fibrosis and necroinflammation. In groups P and L we found a reduction of mean ALT and GGT levels and necroinflammatory score. Group U presented a significant reduction in ALT and GGT levels, without improvement in steatosis, necroinflammation or fibrosis.Atorvastatin and losartan proved to be efficient in the treatment of dyslipidemia- and hypertension-associated NASH, by improving both biochemical parameters and steatosis/ necroinflammation. Pentoxifylline showed similar efficacy in non-hypertensive/non-dyslipidemic patients, while UDCA did not improve the histological score although it improved the biochemical parameters.