Optimal power routing scheme between and within interlinking converters in unbalanced hybrid AC–DC microgrids

An optimal power routing (OPR) scheme between and within interlinking converters (ICs) in unbalanced hybrid AC–DC microgrids to minimise the power imbalance factor at the point of common coupling, active power losses, and voltage deviation indices for microgrids in grid-connected operating mode is proposed in this study. These goals are achieved through a multi-objective optimisation model by optimal distributing of mobile loads between available charging stations and at the same time, OPR within three phases of three-phase four-lag AC/DC converters. Numerical results obtained from implementing the proposed method on the modified IEEE 13-bus system, as an unbalanced hybrid microgrid, and IEEE 34-bus test system, as an unbalanced distribution system, demonstrate that proposed OPR algorithm is successful to satisfy the optimisation goals. For this purpose, four case studies are defined and studied to demonstrate the unique features of the proposed OPR comparing with other power routing schemes. In addition to simulation results, the OPR scheme between ICs is realistically implemented at Florida International University smart grid testbed to show the effect of the power routing on energy losses reduction

The investigation of semantic memory deficit in chronic tinnitus: a behavioral report Investigação do déficit de memória semântica no zumbido crônico: um relato comportamental

Introduction: Tinnitus is a central auditory disorder in which different processing systems are involved as a network. One of these networks is memory. Previous studies have demonstrated some deficits in various types of memory in chronic tinnitus. Objectives: The main purpose of the present study was to investigate the semantic memory, which is not yet investigated in the tinnitus population. Methods: In this case�control study, 15 subjects with chronic tinnitus and 16 matched healthy controls were included. 40 semantically related and 40 semantically unrelated word pairs were presented to the participants in a counter-balanced fashion. They were asked to make decision about their semantic relatedness. Then the participants� reaction times and the accuracy of responses were calculated. Results: Mean of reaction times were significantly longer in the tinnitus group (M = 1034 ms, SD = 0.31) compared to the control group (Mean = 1016 ms, SD = 0.13), p < 0.05. However, no significant difference was found for the mean percentage of correct responses between the two groups. Conclusion: The current study provided behavioral evidence that chronic tinnitus can affect the semantic memory. Such behavioral outcomes may provide new insights into more research activities in the field of electrophysiology and neuroimaging in the tinnitus population. © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facia

The investigation of semantic memory deficit in chronic tinnitus: a behavioral report Investigação do déficit de memória semântica no zumbido crônico: um relato comportamental

Introduction: Tinnitus is a central auditory disorder in which different processing systems are involved as a network. One of these networks is memory. Previous studies have demonstrated some deficits in various types of memory in chronic tinnitus. Objectives: The main purpose of the present study was to investigate the semantic memory, which is not yet investigated in the tinnitus population. Methods: In this case�control study, 15 subjects with chronic tinnitus and 16 matched healthy controls were included. 40 semantically related and 40 semantically unrelated word pairs were presented to the participants in a counter-balanced fashion. They were asked to make decision about their semantic relatedness. Then the participants� reaction times and the accuracy of responses were calculated. Results: Mean of reaction times were significantly longer in the tinnitus group (M = 1034 ms, SD = 0.31) compared to the control group (Mean = 1016 ms, SD = 0.13), p < 0.05. However, no significant difference was found for the mean percentage of correct responses between the two groups. Conclusion: The current study provided behavioral evidence that chronic tinnitus can affect the semantic memory. Such behavioral outcomes may provide new insights into more research activities in the field of electrophysiology and neuroimaging in the tinnitus population. © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facia

An optimal energy management system for real-time operation of multiagent-based microgrids using a T-cell algorithm

The real-time operation of the energy management system (RT-EMS) is one of the vital functions of Microgrids (MG). In this context, the reliability and smooth operation should be maintained in real time regardless of load and generation variations and without losing the optimum operation cost. This paper presents a design and implementation of a RT-EMS based on Multiagent system (MAS) and the fast converging T-Cell algorithm to minimize the MG operational cost and maximize the real-time response in grid-connected MG. The RT-EMS has the main function to ensure the energy dispatch between the distributed generation (DG) units that consist in this work on a wind generator, solar energy, energy storage units, controllable loads and the main grid. A modular multi-agent platform is proposed to implement the RT-EMS. The MAS has features such as peer-to-peer communication capability, a fault-tolerance structure, and high flexibility, which make it convenient for MG context. Each component of the MG has its own managing agent. While, the MG optimizer (MGO) is the agent responsible for running the optimization and ensuring the seamless operation of the MG in real time, the MG supervisor (MGS) is the agent that intercepts sudden high load variations and computes the new optimum operating point. In addition, the proposed RT-EMS develops an integration of the MAS platform with the Data Distribution Service (DDS) as a middleware to communicate with the physical units. In this work, the proposed algorithm minimizes the cost function of the MG as well as maximizes the use of renewable energy generation; Then, it assigns the power reference to each DG of the MG. The total time delay of the optimization and the communication between the EMS components were reduced. To verify the performance of our proposed system, an experimental validation in a MG testbed were conducted. Results show the reliability and the effectiveness of the proposed multiagent based RT-EMS. Various scenarios were tested such as normal operation as well as sudden load variation. The optimum values were obtained faster in terms of computation time as compared to existing techniques. The latency from the proposed system was 43% faster than other heuristic or deterministic methods in the literature. This significant improvement makes this proposed system more competitive for RT applications

Improved HPLC method for determination of four PPis, omeprazole, pantoprazole, lansoprazole and rabeprazole in human plasma

PURPOSE: To develop a simple and rapid HPLC method for measuring of four proton-pump inhibitors (PPIs), omeprazole (OPZ), pantoprazole (PPZ), lansoprazole (LPZ) and rabeprazole (RPZ) concentrations in human plasma. METHODS: Following a single step liquid-liquid extraction analytes along with an internal standard (IS) were separated using an isocratic mobile phase of phosphate buffer (10 mM)/acetonitrile (53/47, v/v adjusted pH to 7.3 with triethylamine) at flow rate of 1 mL/min on reverse phase TRACER EXCEL 120 ODS-A column at room temperature. RESULTS: Total analytical run time for selected PPIs was 10 min. The assays exhibited good linearity (r2&gt;0.99) over the studied range of 20 to 2500 ng/mL for OPZ, 20 to 4000 ng/mL for PPZ, 20 to 3000 ng/mL for LPZ and 20 to 1500 ng/mL for RPZ. The recovery of method was equal or greater than 80 and lower limit of quantification (LLOQ) was 20 ng/mL for four PPIs. Coefficient of variation and error at all of the intra-day and inter-day assessment were less than 9.2 for all compounds. CONCLUSIONS: The results indicated that this method is a simple, rapid, precise and accurate assay for determination of four PPIs concentrations in human plasma. This validated method is sensitive and reproducible enough to be used in pharmacokinetic studies and also is time- and cost-benefit when selected PPIs are desired to be analyzed

Stabilization and Anticancer Enhancing Activity of the Peptide Nisin by Cyclodextrin-Based Nanosponges against Colon and Breast Cancer Cells

The great variability of cancer types demands novel drugs with broad spectrum, this is the case of Nisin, a polycyclic antibacterial peptide that recently has been considered for prevention of cancer cells growth. As an accepted food additive, this drug would be very useful for intestinal cancers, but the peptide nature would make easier its degradation by digestion procedures. For that reason, the aim of present study to investigate the protective effect of two different β-cyclodextrin-based nanosponges (carbonyl diimidazole and pyromellitic dianhydride) and their anti-cancer enhancement effect of Nisin-Z encapsulated with against colon cancer cells (HT-29). To extend its possible use, a comparison with breast (MCF-7) cancer cell was carried out. The physicochemical properties, loading efficiency, and release kinetics of Nisin complex with nanosponges were studied. Then, tricin-SDS-PAGE electrophoresis was used to understand the effect of NSs on stability of Nisin-Z in the presence of gastric peptidase pepsin. In addition, the cytotoxicity and cell membrane damage of Nisin Z were evaluated by using the MTT and LDH assay, which was complemented via Annexin-V/ Propidium Iodide (PI) by using flowcytometry. CD-NS are able to complex Nisin-Z with an encapsulation efficiency around 90%. A protective effect of Nisin-Z complexed with CD-NSs was observed in presence of pepsin. An increase in the percentage of apoptotic cells was observed when the cancer cells were exposed to Nisin Z complexed with nanosponges. Interestingly, Nisin Z free and loaded on PMDA/CDI-NSs is more selectively toxic towards HT-29 cells than MCF-7 cancer cells. These results indicated that nanosponges might be good candidates to protect peptides and deliver drugs against intestinal cancers

Xanthomicrol is the main cytotoxic component of Dracocephalum kotschyii and a potential anti-cancer agent

Spinal-Z, a methanolic mixture of dried powdered seeds of Peganum harmala Linn. and leaf of Dracocephalum kotschyii Boiss. is an Iranian ethno-medical remedy. It has been used for the treatment of various types of cancer for many years. To evaluate the use of Spinal-Z in treatment of cancer, we examined its effects against a panel of malignant cell lines and tumors induced in mice. The in vitro antiproliferative activities of Spinal-Z, the seed extract of P. harmala and the leaf extract of D. kotschyii were determined using the MTT assay. The concentration of the agent required to inhibit cell growth by 50 (IC50) was estimated. In addition, the anti-tumor activities of the remedy and its constituents were investigated. Viability of cells treated with Spinal-Z and its components decreased in a dose dependent manner. Spinal-Z and its components showed cytotoxic effects against all cell lines tested. The leaf extract of D. kotschyii showed a greater preferential cytotoxic effect than the seed extract of P. harmala and Spinal-Z, on all cell lines tested. Harmine showed cytotoxicity against HL60 and K562 cell lines. This could explain the cytotoxic effect of P. harmala on these cells. The leaf extract of D. kotschyii was able to inhibit tumor proliferation in mice. The active ingredient in the leaf extract of D. kotschyii appears to be a flavone identified as xanthomicrol. Xanthomicrol was able to inhibit proliferation of a number of malignant cells. The cytotoxic effects of xanthomicrol were more selective towards malignant cells than doxorubicin. © 2005 Elsevier Ltd. All rights reserved

Paraoxonase phenotype distribution in a healthy Iranian population

Human serum paraoxonase (PON1) is a high-density lipoprotein-associated esterase that protects against organophosphate neurotoxicity, and is proposed to play a role in lipid metabolism and the onset of cardiovascular disease. In the present study, paraoxonase activities and phenotype distribution in serum of 132 healthy Iranian individuals aged 17-68 years were assessed using dual substrate method. In the study population, a wide interindividual variability (up to 15-fold) of paraoxonase activity was found. The mean of basal, salt-stimulated paraoxonase and arylesterase activities were 81.8 ± 57 U/ml, 153.1 ± 117.5 U/ml and 80.7 ± 12.8 kU/l, respectively. The ratio of salt-stimulated paraoxonase activity to arylesterase activity was used for definition of phenotypes. Based on the observed ratios, three distinct phenotypes AA (low activity), AB (intermediate activity) and BB (high activity) were determined. The PON1 ratio varied from 0.5 to 6.8. The paraoxonase phenotype frequencies were approximately 48 (AA), 41 (AB) and 11 (BB). In this work, serum triglycerides had significant positive correlation (r = 0.334, P < 0.05) with paraoxonase activity, whereas high-density lipoprotein did not. No significant decrease in paraoxonase activity by smoking was observed. Age and sex had no influences on PON1 activities. In conclusion, the distribution of paraoxonase phenotypes in this Iranian population was trimodal and comparable to that of Caucasians from North America; however, overall enzyme activity was lower than that reported for Caucasians. © 2007 The Authors

Frequency of paraoxonase 192/55 polymorphism in an Iranian population

Paraoxonase (PON1) is a serum enzyme that plays an important role in prevention of atherosclerosis and also protects against organophosphate-induced neurotoxicity. PON1 displays a high variablility in human populations. In this study, PON1-192 and -55 polymorphisms and correlation to serum PON1 activity were investigated in 132 healthy Iranian individuals from Isfahan province. The genotype frequencies for PON1-192 were approximately 48 (QQ), 42. (QR), and 10 (RR) and for PON1-55 17 (MM), 48 (ML), and 35 (LL). Thus, the frequencies of alleles R and L were 0.31 and 0.59, respectively. PON1 activity toward paraoxon was markedly affected in both polymorphic populations in the following order QQ < QR < RR genotype for PON1-192 and MM < ML < LL genotype for PON1-55. Neither polymorphism significantly affected PON1 activity toward phenylacetate. The RR/LL individuals had the highest PON1 activity and QQ/MM individuals the least. The QR/ML haplotype was the most frequent seen in Iranians, and the RR/MM and QR/MM haplotypes were absent in this population. In conclusion, the frequencies of PON1-192 and -55 polymorphisms in this Iranian population were different from those seen in other Asian populations from Japan and China but similar to those for European Caucasians. Copyright © Taylor & Francis Group, LLC

Alterations in early auditory evoked potentials and brainstem transmission time associated with tinnitus residual inhibition induced by auditory electrical stimulation

Introduction: Residual inhibition (RI) is the temporary inhibition of tinnitus by use of masking stimuli when the device is turned off. Objective: The main aim of this study was to evaluate the effects of RI induced by auditory electrical stimulation (AES) in the primary auditory pathways using early auditory-evoked potentials (AEPs) in subjective idiopathic tinnitus (SIT) subjects. Materials and Methods: A randomized placebo-controlled study was conducted on forty-four tinnitus subjects. All enrolled subjects based on the responses to AES, were divided into two groups of RI and Non-RI (NRI). The results of the electrocochleography (ECochG), auditory brain stem response (ABR) and brain stem transmission time (BTT) were determined and compared pre- and post-AES in the studied groups. Results: The mean differences in the compound action potential (CAP) amplitudes and III/V and I/V amplitude ratios were significantly different between the RI, NRI and PES controls. BTT was significantly decreased associated with RI. Conclusion: The observed changes in AEP associated with RI suggested some peripheral and central auditory alterations. Synchronized discharges of the auditory nerve fibers and inhibition of the abnormal activity of the cochlear nerve by AES may play important roles associated with RI. Further comprehensive studies are required to determine the mechanisms of RI more precisely