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Considering the ongoing evolution of flexible printed circuit boards and the importance of safeguarding the intellectual property of circuit designs, there exists an imperative demand for the development of a black film exhibiting exceptional electrical properties and remarkable light‐shielding capabilities. Consequently, this work employs a straightforward strategy to enhance the opacity of polyimide films by incorporating carbon black (CB) and manganese dioxide (MnO2) as black fillers using an in situ doping method. Rigorous tests are conducted, analyzing properties such as dielectric constant, dielectric loss, breakdown field strength, current density, and ferroelectric energy storage. The optimal ratio of CB to MnO2 (mass fraction) is determined as 1:5, with a total powder doping amount of 6 wt%, providing the best ratio relative to the matrix resin. This ratio ensures an optimal powder dispersion state, resulting in an outstanding breakdown field of 147.4 kV/mm and ultralow dielectric constants, measuring less than 3.78 at 103 Hz. This composite film is anticipated to find applications as a cutting‐edge material for electronic devices and the semiconductor industry. [ABSTRACT FROM AUTHOR]

Background: In the study, we aimed to evaluate the ability of micro‐histology combined with cytology to improve the quality of slides and diagnose endometrial lesions. Methods: Endometrial specimens were collected from Li Brushes. Every specimen was prepared for micro‐histological and cytological slides, using cell block (CB) and liquid‐based cytology (LBC) technologies. Semi‐quantitative scoring system was used to evaluate the qualities of slides. CB slides were assessed by 5‐category scoring system. Diagnostic accuracy was calculated in LBC, CB, and LBC + CB groups based on the histological gold standard. Endometrial atypical hyperplasia, and endometrial cancer were considered positive, whereas others were considered negative. Results: A total of 167 patients were enrolled. CB slides were inferior to LBC slides only in cellularity (p < 0.001), but superior in the other six parameters (all p < 0.001). The satisfaction rate of micro‐histology accounted for 92.3%. The accuracy index in the CB group was higher than in the LBC group in terms of sensitivity (85.5% vs. 82.7%) and specificity (98.9% vs. 95.7%). The sensitivity and specificity in the LBC + CB group were increased to 94.2% and 99.0%, respectively. Conclusions: The quality of micro‐histological slides was higher than that of cytological slides. By combining micro‐histology with cytology, higher accuracy was achieved for endometrial lesions diagnosis. [ABSTRACT FROM AUTHOR]

Phasor measurement units (PMUs) are currently the most useful devices to obtain fast, precise, and synchronised measurement data. Owing to the high cost of installation, the minimum number of PMUs required for the full observability of a network must be determined. However, power companies do not consider such optimal PMU installation (OPI), because their main concerns are preventing cascaded tripping and secure grid separation, for which critical buses (CBs) should be prioritised for direct observability. In practice, utility grids (UGs) may lose their full observability status during islanding, which the OPI problem should account for. On the other hand, actual bus‐to‐bus variations in the PMU installation cost are not properly addressed in the PMU installation problem. Considering these practical aspects, an operational‐based multiphase PMU installation approach is proposed here using the grey wolf optimisation algorithm for CB prioritisation. A PMU cost minimisation‐based OPI problem that considers the full observability of each UG during islanding is formulated. To determine quality outputs, logical and unique mathematical equations are developed. A novel multiple bus selection approach is proposed for a phase‐wise bus assortment. The results of the proposed algorithm are compared with those of other existing methods. [ABSTRACT FROM AUTHOR]

Studying the characteristics of transient recovery voltage (TRV) becomes mandatory for selectingan appropriate circuit breaker (CB) in terms of protection and control of thepower system network. A CB may fail to interrupt the short circuit faults if itsrated TRV characteristic is lower than that of the power system characteristics.This paper aims to extract the net TRV waveform imposed on the breaker contactswithout any prior knowledge about the system parameters. Better accuracy isachieved in the measurement of TRV parameters because the power frequencycomponent superimposed on the raw waveform has been removed. Based on theconcept of the second order generalized integrator‐adaptive notch filter(SOGI‐ANF), the behaviour of the TRV over time has been studied. The prominentadvantage of the presented method is that it is independent from the circuitconfiguration and voltage and thus can be performed online on different types ofpower networks. The adaptive feature of the SOGI‐ANF and its simple structuremake it a suitable tool for analysis of TRV in power system networks. Thereal‐time implementation of the SOGI‐ANF has been obtained using an STM32F4Discovery microcontroller board and experimental results show the effectivenessof the proposed method.[AQ ID=Q2] [ABSTRACT FROM AUTHOR]

Half‐bridge modular multi‐level converter‐based multi‐terminal HVDC (HB‐MMC‐MTDC) technology is increasingly adopted as a promising option in the power transmission and distribution fields. However, how to cut off DC fault currents safely and ensure the continuous operation of the healthy parts of the HB‐MMC‐MTDC system under DC faults presents a huge challenge. This study proposes a generalised protection strategy on the use of a new RL‐fault current limiter (FCL) branch and hybrid DC circuit breakers (CBs), to deal with the bipolar DC faults for a given HB‐MMC‐MTDC system. It contributes to cut off the DC fault current before triggering MMC blocking, without influencing the continuous operation of the healthy parts of MTDC system. The operation characteristics of hybrid DC CBs and the equivalent circuit for the DC fault current is introduced, and the mathematical model of the DC fault current with the new RL‐FCL is discussed in detail. Theoretical and data analyses are performed to obtain the feasible parameters of the RL‐FCL. Simulation tests of an HB‐MMC‐MTDC system with different topologies are performed in PSCAD/EMTDC to validate the effectiveness of the generalised protection strategy. [ABSTRACT FROM AUTHOR]

Recently, remote‐controllable actuators for circuit breaker (CB) have attracted attention for the smart grid electric power system. In this study, diverse kinds of remote‐controllable electromagnetic actuator for CB are precisely investigated to give a guideline for the selection of the effective actuator according to numerous voltage level of CB. In case of a low‐voltage level of CB, the separated permanent‐magnet actuator (SPMA) is verified in this research as the most suitable actuator through the comparison with diverse electromagnetic actuators. The SPMA is designed for the 225AF moulded case CB by using the proposed optimisation method, which the authors termed as a multi‐step optimisation strategy. [ABSTRACT FROM AUTHOR]

Several cancellable biometrics (CBs) techniques have been proposed to protect biometric data and maintain users' privacy. Although such techniques can withstand brute‐force and/or pre‐image attacks, they are vulnerable to correlation attacks. In this study, the authors propose a novel correlation attack‐resistant CBs scheme that is based on a convolution operation and a bidirectional associative memory (BAM) neural network. The proposed scheme utilises BAM to bind biometric templates to random bit‐strings in a secure and efficient manner. These random bit‐strings are then employed to derive cancellable templates from the true templates linked to them via BAM weights, which are safely stored with the generated cancellable template in the system database. In this study, linear convolution is adopted as the cancellable transformation process. The result of convolving the original biometric template with the transformation key is binarised according to a predefined threshold to thwart blind de‐convolution. The security of the proposed scheme against different attacks is analysed and experiments on the CASIA‐IrisV3‐Interval dataset illustrate the efficacy of the proposed scheme. [ABSTRACT FROM AUTHOR]

This paper proposes a circuit breaker (CB) condition assessment model which combines the fuzzy set theory, the analytical hierarchy process (AHP) and evidential reasoning (ER). Four assessment factors, that is, (i) electrical characteristics, (ii) mechanical characteristics, (iii) insulation characteristics and (iv) miscellaneous factors, are selected as the condition parameters. A hierarchical assessment index system is constructed based on preventive tests data, intelligent electronic device monitoring data, maintenance data and operating environment. The inputted condition parameters indices are processed by the membership functions of a fuzzy distribution to obtain relative impairment grades which represent the relative grade of the CB condition towards the fault. The weights of the CB condition factors and indices are generated by the AHP based on experts' interviews and feedbacks, and the final assessment is determined by ER according to the decision factors combined. An intelligent maintenance model is built with field examples to demonstrate the effectiveness of the proposed model in assessing the CB operation conditions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Collection strategy is the first step for collecting good quality cord blood (CB) units. There are two principal different techniques to collect CB from the umbilical vein: in the delivery room while the placenta is still in the uterus by midwives and obstetricians or in an adjacent room after placental delivery by CB-bank trained personnel. In this study, the benefits and disadvantages between two different CB collection strategies were evaluated in order to improve CB bank methodology.Design and Methods: Valencia CB bank maintains the two different collection strategies aforementioned. Before processing CB units, volume was calculated and samples were drawn for cell counts. After processing and before cryopreservation, samples for cell counts, CD34 analysis, viability, clonogenic assays and microbiology were drawn directly from the bags. We compared the efficiency of the two collection techniques.Results: Obstetric date and umbilical CB was obtained from 848 vaginal (484 collected in uterus and 364 collected ex uterus). The proportion of excluded CB units before processing was 33% for ex uterus and 25% for in uterus. The difference was statistically significant. A larger volume and a higher number of total nucleated cells, CD34+ cells and CFUs were harvested in the in uterus collection group.Interpretation and Conclusions: Based on our findings, we conclude that the mode of collection influences the hematopoietic content of CB donations. Collection before placental delivery is the best approach to CB collection and allows optimizing CB bank methodology. [ABSTRACT FROM AUTHOR]

Abstract Recent evidence obtained in rat models of Parkinson's disease showed that the density of cannabinoid CB1 receptors and their endogenous ligands increase in basal ganglia. However, no data exists from post-mortem brain of humans affected by Parkinson's disease or from primate models of the disorder. In the present study, we examined CB1 receptor binding and the magnitude of the stimulation by WIN55,212-2, a specific CB1 receptor agonist, of [35S]GTPγS binding to membrane fractions from the basal ganglia of patients affected by Parkinson's disease. In Parkinson's disease, WIN55,212-2-stimulated [35S]GTPγS binding in the caudate nucleus, putamen, lateral globus pallidus and substantia nigra was increased, thus indicating a more effective activation of GTP-binding protein-coupled signalling mechanisms via CB1 receptors. This was accompanied by an increase in CB1 receptor binding in the caudate nucleus and the putamen, although no changes were observed in the lateral globus pallidus and the substantia nigra. Because Parkinson's disease patients had been chronically treated with l-DOPA, brains were studied from normal common marmosets and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated animals with and without chronic L-DOPA treatment. MPTP-lesioned marmosets had increased CB1 receptor binding in the caudate nucleus and the putamen compared to control marmosets, as well as increased stimulation of [35S]GTPγS binding by WIN55,212-2. However, following l-DOPA treatment these parameters returned towards control values. The results indicate that a nigro-striatal lesion is associated with an increase in CB1 receptors in the basal ganglia in humans and nonhuman primates and that this increase could be reversed by chronic l-DOPA therapy. The data suggest that CB1 receptor blockade might be useful as an adjuvant for the treatment of parkinsonian motor symptoms. [ABSTRACT FROM AUTHOR]

For the past few years there has been controversial discussion of whether environmental pollutants in general, and chlorinated hydrocarbons in particular, may impair male fertility. Organochlorine compounds, e.g. dichlorodiphenyltrichlorothane (DDT) and metabolites, polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) are highly persistent in the environment and there is therefore some concern about human exposure. These chlorinated compounds are universally found in human body fluids. Substantial amounts are detected in human body fluids associated with reproduction such as follicular fluid, seminal fluid and cervical mucus. The available data on male fertility and organochlorines are scarce and controversial. Fertilization rates in in vitro fertilization procedures were found to be decreased in couples in whom the male partner was exposed to pesticides. Data on the effects of PCBs on human sperm motility and acrosome reaction in vitro are controversial. Various PCDD congeners had no effect on human sperm motility in vitro. Effects of chlorinated hydrocarbons on sperm function in vivo seem to be unlikely since the concentrations used in vitro were far higher than those found in fluids of the human reproductive tract. However, negative effects on human spermatozoa in vivo cannot be totally excluded because other organohalogen compounds can be identified in the genital tract and little is known about their synergistic effects. [ABSTRACT FROM AUTHOR]

Abstract CB1 cannabinoid receptors are widely distributed in the central nervous system where they mediate most of the cannabinoid-induced responses. Here we have evaluated the interactions between the CB1 cannabinoid receptors and the endogenous opioid system by assaying a number of well-characterized opioid responses, e.g. antinociception and stress-mediated effects, on mutant mice in which the CB1 receptor gene was invalidated. The spontaneous responses to various nociceptive stimuli (thermal, mechanical and visceral pain) were not changed in mutant CB1 mice. Furthermore, the absence of the CB1 cannabinoid receptor did not modify the antinociceptive effects induced by different opioid agonists: morphine (preferential mu opioid agonist), d-Pen2-d-Pen5-enkephalin (DPDPE) and deltorphin II (selective delta opioid agonists), and U-50,488H (selective kappa opioid agonist) in the hot-plate and tail-immersion tests. In contrast, the stress-induced opioid mediated responses were modified in CB1 mutants. Indeed, these mutants did not exhibit antinociception following a forced swim in water at 34 °C and presented a decrease in the immobility induced by the previous exposure to electric footshock. However, the antinociception induced by a forced swim in water at 10 °C was preserved in CB1 mutants. These results indicate that CB1 receptors are not involved in the antinociceptive responses to exogenous opioids, but that a physiological interaction between the opioid and cannabinoid systems is necessary to allow the development of opioid-mediated responses to stress. [ABSTRACT FROM AUTHOR]

Abstract: Chronic treatment of rats with ▵9-tetrahydrocannabinol (▵9-THC) results in tolerance to its acute behavioral effects. In a previous study, 21-day ▵9-THC treatment in rats decreased cannabinoid activation of G proteins in brain, as measured by in vitro autoradiography of guanosine-5′-O-(3-[35S]thiotriphosphate) ([35S]GTPγS) binding. The present study investigated the time course of changes in cannabinoid-stimulated [35S]GTPγS binding and cannabinoid receptor binding in both brain sections and membranes, following daily ▵9-THC treatments for 3, 7, 14, and 21 days. Autoradiographic results showed time-dependent decreases in WIN 55212-2-stimulated [35S]GTPγS and [3H]WIN 55212-2 binding in cerebellum, hippocampus, caudate-putamen, and globus pallidus, with regional differences in the rate and magnitude of down-regulation and desensitization. Membrane binding assays in these regions showed qualitatively similar decreases in WIn 55212-2-stimulated [35S]GTPγS binding and cannabinoid receptor binding (using [3H]SR141716A), and demonstrated that decreases in ligand binding were due to decreases in maximal binding values, and not ligand affinities. These results demonstrated that chronic exposure to ▵9-THC produced time-dependent and region-specific down-regulation and desensitization of brain cannabinoid receptors, which may represent underlying biochemical mechanisms of tolerance to cannabinoids. [ABSTRACT FROM AUTHOR]

Abstract It is generally accepted that the phospholipase-A2 -cyclooxygenase-prostanoids-cascade mediates spinal sensitization and hyperalgesia. However, some observations are not in line with this hypothesis. The aim of the present work was to investigate whether different components of this cascade exhibit nociceptive or antinociceptive effects in the rat formalin test. Intrathecal (i.th.) injection of prostaglandin E2 (PGE2 ) induced a dose-dependent antinociceptive effect on the formalin-induced nociception. Furthermore, thimerosal, which inhibits the reacylation of arachidonic acid thereby enhancing arachidonic acid levels, had an antinociceptive effect rather than the expected pronociceptive effect when given i.th. While the phospholipase A2 inhibitor methyl arachidonyl fluorophosphonate (MAFP; i.th.) had a significant antinociceptive effect, its analogue palmitoyl trifluoromethyl ketone (PTFMK; i.th.) had no significant effect on the formalin-induced nociception. However, MAFP, but not PTFMK, showed a cannabinoid CB1 agonistic effect as shown by the inhibition of electrically evoked contractions of the vas deferens isolated from CB1 wild-type mice but not of that from CB1 knockout mice. The antinociceptive effect of MAFP was completely reversed by the CB1 receptor antagonist AM-251 (i.th.), thus attributing such effect to its CB1 agonistic effect. Moreover, the antinociceptive effect of the cyclooxygenase inhibitor, flurbiprofen (i.th.) was reversed by the co-administration of AM-251, but not by PGE2 . Finally. the combination of phenylmethylsulfonyl fluoride (PMSF; intraperitoneal), which inhibits the degradation of anandamide through the inhibition of fatty acid amidohydrolase, with thimerosal (i.th.) produced a profound CB1 -dependent antinociception. The present results show that endocannabinoids play a major role in mediating... [ABSTRACT FROM AUTHOR]

Abstract The search for new ocular hypotensive agents represents a frontier of current eye research because blindness due to optic neuropathy occurs insidiously in 10% of all patients affected by glaucoma. Cannabinoids have been proposed to lower intraocular pressure by either central or peripheral effects but a specific mechanism for this action has never been elucidated. We recently demonstrated the presence of the central cannabinoid receptor (CB1) mRNA and protein in the human ciliary body. In the present study we show that the synthetic CB1 receptor agonist, WIN 55212–2, applied topically at doses of 25 or 50 µg (n = 8), decreases the intraocular pressure of human glaucoma resistant to conventional therapies within the first 30 min (15 ± 0.5% and 23 ± 0.9%, respectively). A maximal reduction of 20 ± 0.7% and 31 ± 0.6%, respectively, is reached in the first 60 min. These data confirm that CB1 receptors have direct involvement in the regulation of human intraocular pressure, and suggest that, among various classes of promising antiglaucoma agents, synthetic CB1 receptor agonists should deserve further research and clinical development. [ABSTRACT FROM AUTHOR]