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[Display omitted] • Develop an electrically assisted stereolithography 3D printing strategy to manufacture BaTiO 3 -resin composites with graded permittivity. • Optimize the printing parameters (e.g. , resin formulation, exposure time, the driven electric field strength and duration) to fabricate high-loaded BaTiO 3 -filled composites. • As proof of concept, an encapsulation component with graded permittivity and adaptive insulating properties for IGBTs was fabricated. Insulated gate bipolar transistors (IGBTs) find applications in diverse fields, such as integrated motor drives, controllable power systems, and electric vehicles. However, traditional IGBT encapsulation materials are unsuitable for high-voltage applications due to the excessive electric field stress generated at the triple junction; an insulation-enhanced encapsulation material is therefore necessary. Here, using an electrically assisted stereolithography (SLA) 3D printing strategy, we fabricate an encapsulation material with graded permittivity that can uniform the electric field stress distribution in IGBTs. Compared with pure resin and uniform-dispersed BaTiO 3 -resin composite encapsulation, the graded BaTiO 3 -resin composite reduces the generated maximum electric field stress (E m a x ) from 190.2 to 108.3 kV/mm (nearly a 50% decrease). Regarding the partial discharge inception voltage, the devices packaged with graded BaTiO 3 -resin composite (4.07 kV) also performed better than devices packaged with resin (1.96 kV) and uniform-dispersed BaTiO 3 -resin composite (2.51 kV). This novel electrically assisted SLA 3D printing strategy will open a new window for the in-situ encapsulation of IGBTs and other microelectronics. [ABSTRACT FROM AUTHOR]

Snake venom is considered a "toxin arsenal", and it often induces a series of clinical and pathophysiological symptoms in snakebite victims. Interestingly, toxin inhibitors are commonly found in the serum of snakes and their predators. Sinonatrix annularis is a type of non-venomous snake that was reported to contain an "inhibitor cocktail", including phospholipase A 2 inhibitors (PLIs), metalloproteinase inhibitors (SVMPIs), and small serum protein (SSP). However, the sequences and activities of these components remain obscure. In this study, we performed envenomation challenges on S. annularis using venoms from Deinagkistrodon acutus , Agkistrodon halys and Naja atra. In brief, the maximum injected amount of venom was 360 mg/kg for D. acutus , 72 mg/kg for A. halys , and 18 mg/kg for N. atra. The mRNA expression of the inhibitors PLIα, PLIβ, PLIγ, SVMPI, serpin A1, and SSP showed a dose-dependent effect on envenomation. Liver homogenate from S. annularis (LH) was prepared and used to evaluate its inhibitory effect on snake venoms. As a result, LH showed significant neutralization of venom PLA 2 , mitigated hemorrhage, venom-induced muscle damage, and system toxicity. In the presence of LH, envenomated mice exhibited attenuated inflammation, apoptosis, oxidative damage, and mitigated changes in serum biochemical markers caused by venom. The study reveals the secret of "natural immunity" in snakes, namely, the "antivenom", which consists of an inhibitor proteome or cocktail. [Display omitted] • S. annularis showed good tolerance to different snake venoms due to their intrinsic inhibitor cocktail. • The inhibitors were upregulated in a dose-dependent manner in response to venom exposure. • The liver homogenate of S. annularis attenuated envenoming symptoms in victim mice. [ABSTRACT FROM AUTHOR]

A novel phospholipaseA 2 (PLA 2 ) inhibitory protein (PLI) was purified from the serum of Macropisthodon rudis , a non-venomous snake mainly found in southern China. The molecular mass of the purified PLI was 160 kDa as determined by Superdex 200HR; however, the PLI protein had only one subunit of 25.4 kDa as determined by 12% SDS-PAGE, indicating an oligomeric protein. PLI cDNA obtained by PCR from the liver of Macropisthodon rudis, revealed 549 bps coding for a mature protein of 183 amino acid residues. Based on an amino acid sequence alignment with venomous and non-venomous snakes, this inhibitor was determined to be in the γ type family of PLI. In vitro experiments showed that PLIγ inhibited enzymatic, inflammatory, and antibacterial activities of snake venom PLA 2 isolated from Agkistrodon acutus. [ABSTRACT FROM AUTHOR]

• An explicit topology-variable-based reliability assessment for ADHDS planning is proposed. • A linearized power flow for ADHDS planning model is formulated. • A Globally Pareto-optimal set for reliability and economy is constructed based on adaptive ε-constraint method. • Key factors that restrict the development of DC distribution system are revealed. • ADHDS can provide a promising solution to the system with high proportion of DC elements. AC-DC hybrid structure offers a promising solution to accommodate AC/DC loads and distributed generators (DGs) in future smart grid. However, due to the complexity brought by reliability assessment and hybrid power flow, almost existing planning models of AC/DC hybrid distribution systems (ADHDS) are solved by heuristic algorithms, which cannot guarantee the optimality of solution. A novel ADHDS planning model that achieves two objectives: economy and reliability (double Q planning technique) is established in this paper. This novel planning model incorporates reliability indices, i.e., SAIDI, SAIFI, and EENS explicitly, which established the relationship between reliability and planning topology with an explicit method. Moreover, a linearized hybrid power flow for ADHDS planning is utilized in this paper. Finally, ADHDS planning model can be established as MILP and solved efficiently. Further, a globally Pareto-optimal set for reliability and economy is constructed based on adaptive ε-constraint method, enabling planners to make better trade-offs. Case studies demonstrate that ADHDS outperform than pure AC or DC solution for systems with high proportion of DC elements, effectively reducing distribution system cost with low-level reliability sacrifice. Besides, the effect of DG penetration, DC proportion, and failure rate of voltage source converter (VSC) on optimal double Q planning solution are revealed. [ABSTRACT FROM AUTHOR]

Snakebite envenomation often induces acute kidney injury (AKI) and acute liver injury (ALI), leading to augmented injuries and poor rehabilitation. Phospholipase A 2 (PLA 2) and metalloproteinase (SVMP) present in venom are responsible for the envenomation-associated events. In this study, mice envenomed with Deinagkistrodon acutus , Naja atra , or Agkistrodon halys pallas venom exhibited typical AKI and ALI symptoms, including significantly increased plasma levels of myoglobin, free hemoglobin, uric acid, aspartate aminotransferase, and alanine aminotransferase and upregulated expression of kidney NGAL and KIM-1. These effects were significantly inhibited when the mice were pretreated with natural inhibitors of PLA 2 and SVMP isolated from Sinonatrix annularis (SaPLIγ and SaMPI). The inhibitors protected the physiological structural integrity of the renal tubules and glomeruli, alleviating inflammatory infiltration and diffuse hemorrhage in the liver. Furthermore, the dual therapy alleviated oxidative stress and apoptosis in the kidneys and liver by mitigating mitochondrial damage, thereby effectively reducing the lethal effect of snake venom in the inhibitor-treated mouse model. This study showed that dual therapy with inhibitors of metalloproteinase and phospholipase can effectively prevent ALI and AKI caused by snake bites. Our findings suggest that intrinsic inhibitors present in snakes are prospective therapeutic agents for multi-organ injuries caused by snake envenoming. [Display omitted] • Snake venom induces mitochondrial damage. • Snake venom promotes redox imbalance and apoptosis. • Dual inhibitors prevent SAKI and SALI development. • Dual inhibitors maintain mitochondrial membrane potential. [ABSTRACT FROM AUTHOR]

SaPLIγ is a novel gamma phospholipase A 2 inhibitor (PLI) recently isolated from Sinonatrix annularis , a Chinese endemic non-venomous snake. To explore the neutralization effects of saPLIγ in snakebite envenomation, a dose equivalent to LD 50 of Deinagkistrodon acutus , Agkistrodon halys and Naja atra venom with/without saPLIγ was inoculated into the gastrocnemius muscle of female Kunming mice. The ability of saPLIγ to inhibit myonecrosis and systemic toxicity were evaluated through investigations of muscle histopathology, and determination of the serum levels of creatine kinase (CK), lactate dehydrogenase isoenzyme1 (LDH1) and aspartate transferase (AST). Edema of the gastrocnemius muscle was evaluated by calculating the width difference between the inoculated limb and the contralateral leg. Desmin loss in the gastrocnemius muscle was determined by Western blot analysis. Co-immunoprecipitation and shotgun LC-MS/MS analyses were performed to identify venom proteins that interact with saPLIγ. All the envenomed mice had significantly elevated serum CK, LDH1 and AST levels, whereas the levels were decreased significantly in the presence of saPLIγ. Histopathological evaluation of gastrocnemius muscle sections showed severe snake venom-induced damage, characterized by leukocyte infiltration and erythrocyte leakage, leading to local edema. Myonecrosis, hemorrhage and desmin loss were significantly attenuated by saPLIγ. SaPLIγ interacted with a wide range of venom proteins, including PLA 2 s, metalloproteinases and C type lectins, which may contribute to broad anti-venom effects. [ABSTRACT FROM AUTHOR]

In this paper, a dynamic current boost technique voltage buffer is presented to enhance the large signal response of low dropout regulators (LDOs). The proposed buffer consists of AC coupling networks and active RC network. Without consuming excess power, this LDO achieves substantial improvement in load transient response. Meanwhile, an enhanced recycling-folded-cascode (RFC) amplifier is employed due to its higher gain, bandwidth and slew rate. In order to ensure the stability of full load, this design adopts simple Miller compensation with a nulling resistor without external equivalent series resistance. Moreover, this paper makes a detailed analysis of LDO in theory and the extensive experimental data verified it. The proposed LDO is successfully fabricated in SMIC 0. 18 μ m CMOS process. The input voltage is 1.8–2.2V and the maximum load current is 200 mA. The experiment results indicate that the undershoot is 84 mV and there is no overshoot when the load current is varied from 0 to 200 mA within 100 ns under the load of 1 μ F load capacitor. [ABSTRACT FROM AUTHOR]

• A novel technique for suppressing secondary arc is described. • The influence of EGC on interrupting performance of CB during out-of-step fault is investigated. • The impact of many factors on the out-of-step fault interruption is systematically discussed. • The failure of reclosure would gives rise to an extremely high TRV and RRRV stressed on CB. The extended grading capacitor (EGC) installed in parallel to multi-break circuit breaker (CB) chamber is a promising technique to suppress secondary arc. The effect of EGC on the interrupting performance of CB during is investigated in this paper. As CBs are subject to various operating burdens in practice, this paper is mainly devoted to the out-of-step fault. Considering the most severe condition, an equivalent circuit model for UHV line is established; the voltages on power source side and line side are derived based on Laplace transform and travelling wave theory, respectively; the expressions of transient recovery voltage (TRV) across CB contact are obtained, and hence the rate of rise of recovery voltage (RRRV). Since the CBs of two power source sides are often cleared asynchronous with a very small-time deviation, the characteristics of TRV waveform for them are separately computed and analysed. Furthermore, a series of sensitivity analysis have been performed. The influences of phase angle, parallel line, shunt reactor as well as reclosure on the interrupting performance are discussed. The results suggest that performance of CB during out-of-step fault is jointly determined by phase angle, parallel line, and especially the reclosure strategy. The EGC can smooth the TRV significantly especially during the first few microseconds of out-of-step fault, the breaking capability would be enhanced. [ABSTRACT FROM AUTHOR]

Since the area of photovoltaic (PV) plant is much larger than conventional power plant, the PV system is exposed to lightning strike at a high risk. A three-dimensional model for the electromagnetic transient in PV array is proposed. Taking lightning channel geometry into account, the magnetic field nearby is derived; the mutual coupling between metal frame of PV panel and thin conductor is then developed. The proposed model is compared with previous methods and validated by experimental results. It suggests that the induced voltage is governed by the magnetic field in essence, and the influences of PV oblique angle, the lightning strike point are discussed in detail. The presence of encapsulated metal frame can produce an opposite magnetic field with respect to original lightning channel and the reduction factor can reach up to 2.58. Furthermore, three installation modes for PV array on mountain terrain are compared. Since part of magnetic flux cross from the wiring-loop surface to the other side and the total flux would decrease, the induced voltage for that installed along the hill ridge is the lowest. As the increase of hillside angle, the induced voltage decays drastically. The results could provide a guideline for lightning protection of PV system on mountain terrain. [ABSTRACT FROM AUTHOR]

• A new technique for suppressing secondary arc is described. • A novel SPAR scheme using an improved VMD algorithm combined with energy entropy is proposed. • The quality factor is raised to determine the optimal decomposition number, and thus avoid modal mixing. • The proposed method is almost not affected by the shunt reactor bank, the fault location, the fault resistance, etc. The extended grading capacitor (GC) for multi-break circuit breaker is a cost-effective method to suppress secondary arc. Since the integration of GC alter the topology of the system, the existing adaptive auto-reclosure scheme should be changed. Considering the characteristics of line voltage waveforms under various faulty conditions, a novel adaptive single-phase reclosing scheme is proposed based on an improved variational mode decomposition (VMD) and energy entropy (EE). The voltage signal extracted from capacitive voltage transformer is decomposed into a series of finite bandwidth intrinsic mode functions (IMF), and then the energy entropy (EE) of each IMF component is computed. To avoid modal mixing, the concept of quality factor is raised. In the case of permanent fault, the natural component of the voltage attenuates fast due to the continuous discharge through the fault point. As time goes, such component approaches zero, and the total voltage becomes more smooth and regular. The EE value also decreases gradually. The EE value is considerably large for the transient fault due to the repetitive re-strike of electric arc, and the EE value has an oscillating trend. The fault type can be distinguished by setting a reasonable threshold. The performance of the proposed method is almost not affected by the installation mode of shunt reactor bank, the fault location, the shunt compensation degree, fault resistance, etc. Both the theoretical analysis and simulation results demonstrate that the proposed method can quickly and accurately identify the fault type. [ABSTRACT FROM AUTHOR]