Search Results (28)

This paper presents a comprehensive register transfer-level (RTL) fault injection study targeting the program counter (PC) of the LEON3 processor, a SPARC V8-compliant core widely used in safety-critical and radiation-prone embedded applications. Using the enhanced NETFI+ framework, over four million faults, including single-event upsets (SEUs), multiple-bit upsets (MBUs), and single-event transients (SETs), were systematically injected into the PC across all pipeline stages. The analysis reveals that early stages, particularly Fetch (FE), Decode (DE), Register Access (RA), and Execute (EX), are highly sensitive to SEU and MBU faults. The propagation of errors detected in the two early stages of the pipeline (FE and DE) is classified with an important percentage of halt execution and timeout traps. Intermediate stages, such as RA and EX, exhibited a higher incidence of silent data corruption and halt execution, while the Memory (ME) and Exception (XC) stages demonstrated greater resilience through fault masking. SET faults were mostly transient and masked, though they occasionally resulted in control flow anomalies. In addition to error classification, detailed trap and exception analysis was performed to characterize fault-induced failure mechanisms. The findings underscore the need for pipeline-stage-specific hardening strategies and highlight the value of simulation-based fault injection for early design validation in safety-critical embedded processors. Full article

The fibrin matrix of thrombi is intertwined with neutrophil extracellular traps (NETs) containing histones that render resistance to fibrinolysis. During NET formation, histones are citrullinated. Our study addresses the question of whether citrullination modifies the fibrin-stabilizing effects of histones. We studied the structure and viscoelastic properties of fibrin formed in the presence of native or citrullinated H1 and core histones by scanning electron microscopy, clot permeation, and oscillation rheometry. The kinetics of fibrin formation and its dissolution were followed by turbidimetry and thromboelastometry. Co-polymerizing H1 with fibrin enhanced the mechanical strength of the clots, thickened the fibrin fibers, and enlarged the gel pores. In contrast, the addition of core histones resulted in a reduction in the fiber diameter, and the pores were only slightly larger, whereas the mechanical stability was not modified. Plasmin-mediated fibrinogen degradation was delayed by native and citrullinated core histones, but not by H1, and the action of des-kringle1-4-plasmin was not affected. Plasmin-mediated fibrinolysis was inhibited by native and citrullinated core histones, and this effect was moderated when the kringle domains of plasmin were blocked or deleted. These findings suggest that in NET-containing thrombi that are rich in core histones, alternative fibrinolytic enzymes lacking kringle domains are more efficient lytic agents than the classic plasmin-dependent fibrinolysis. Full article

Alcohol-related liver disease (ALD) is a leading cause of chronic liver conditions globally. Chronic alcohol consumption induces liver damage through various mechanisms, including neutrophil extracellular trap (NET) formation. Extracellular DNA (ecDNA), released from damaged hepatocytes and NETotic neutrophils, has emerged as a potential biomarker and contributor to liver disease pathology. Enzyme DNases could be an effective therapy for the denaturation of immunogenic ecDNA. This study investigated the circulating ecDNA and NET markers in ALD and therapeutic effect of DNase I in a murine model of ALD. Female C57BL/6J mice were fed a control diet (n = 13) or Lieber–DeCarli ethanol diet for 10 days followed by a binge ethanol dose to mimic acute-on-chronic alcoholic liver injury. From day 5, mice fed ethanol were randomized into an ethanol diet group (n = 17) and ethanol + DNase group (n = 5), which received additional DNase I treatment every 12 h. Liver damage markers were analyzed. Circulating ecDNA and NETosis were measured by fluorometry and cytometry, respectively. DNase I activity was analyzed with single radial enzyme dispersion assay. The ethanol-fed mice exhibited increased mortality, neutrophil infiltration and structural damage in the liver. Total circulating ecDNA levels and NET markers did not differ between groups. DNase activity was higher in ethanol-fed mice compared to controls and additional daily administration of DNase prevented liver injury. These findings suggest that alcohol-induced liver injury modestly influences systemic NETosis and ecDNA levels. However, increased DNase activity can prevent disease progression and enhanced systemic degradation of ecDNA using DNase I. Full article

We discuss the dynamics of a roller coaster cart driven by a constant force along the suspended track of a winding roller coaster. The track is assumed to be arbitrarily long and specially shaped. It is composed of semicircular track portions, in the form of valleys and hills, standing vertically in the same plane. This is a mechanical analog of Josephson junction electrodynamics. To demonstrate the explanatory potential of this analogy, we focus particularly on the conditions of de-trapping of the cart from one of the valleys of the track. This mechanical process has its analog in non-noise-generated premature switching to the finite voltage state of a Josephson junction. Full article

The trapping mechanism at the AlGaN/GaN interface in the p-GaN high electron mobility transistors (HEMTs) and its impact on the turn-on characteristics of direct-coupled FET logic (DCFL) inverters were investigated across various supply voltages (V_DD) and test frequencies (f_m). The frequency-conductance method identified two trap states at the AlGaN/GaN interface (trap activation energy E_c-E_T ranges from 0.345 eV to 0.363 eV and 0.438 eV to 0.47 eV). As V_DD increased from 1.5 V to 5 V, the interface traps captured more electrons, increasing the channel resistance (R_channel) and drift-region resistance (R_drift) of the p-GaN HEMTs and raising the low-level voltage (V_OL) from 0.56 V to 1.01 V. At f_m = 1 kHz, sufficient trapping and de-trapping led to a delay of 220 µs and a V_OL instability of 320 mV. Additionally, as f_m increased from 1 kHz to 200 kHz, a positive shift in the threshold voltage of p-GaN HEMTs occurred due to the dominance of trapping. This shift caused V_OL to rise from 1.02 V to 1.40 V and extended the fall time (t_fall) from 153 ns to 1 µs. This investigation enhances the understanding of DCFL GaN inverters’ behaviors from the perspective of device physics on power switching applications. Full article

In this work, 2D simulations of stainless steel nitriding through a mask were performed with two configurations: with and without lateral adsorption under the mask, depending on the strength of the mask adhesion. The stress-induced diffusion and trapping–detrapping process are included as the main mechanisms of nitrogen mass transport. The main focus is on the analysis of the swelling process, which affects the expansion of the material. The surface concentration profiles and topographical profiles along the surface are calculated and compared with experimentally registered ones taken from the literature, and they show a good agreement. This allows for estimation of the values of model parameters. Because nitriding processes takes place in vertical and horizontal directions, the anisotropic aspect of nitriding are analyzed. It is shown that the adherence of the mask significantly influences the topographical profile and the anisotropy of nitriding, because in the case of a weakly adhered mask, a lateral adsorption process takes place under the mask. The influence of swelling and anisotropy in the case of pattern nitriding in small dimensions is discussed. Full article

GaN HEMT devices are sensitive to the single event effect (SEE) caused by heavy ions, and their reliability affects the safe use of space equipment. In this work, a Ge ion (LET = 37 MeV·cm²/mg) and Bi ion (LET = 98 MeV·cm²/mg) were used to irradiate Cascode GaN power devices by heavy ion accelerator experimental device. The differences of SEE under three conditions: pre-applied electrical stress, different LET values, and gate voltages are studied, and the related damage mechanism is discussed. The experimental results show that the pre-application of electrical stress before radiation leads to an electron de-trapping effect, generating defects within the GaN device. These defects will assist in charge collection so that the drain leakage current of the device will be enhanced. The higher the LET value, the more electron–hole pairs are ionized. Therefore, the charge collected by the drain increases, and the burn-out voltage advances. In the off state, the more negative the gate voltage, the higher the drain voltage of the GaN HEMT device, and the more serious the back-channel effect. This study provides an important theoretical basis for the reliability of GaN power devices in radiation environments. Full article

This paper investigates the threshold voltage shift (ΔV_TH) induced by positive bias temperature instability (PBTI) in silicon carbide (SiC) power MOSFETs. By analyzing ΔV_TH under various gate stress voltages (V_Gstress) at 150 °C, distinct mechanisms are revealed: (i) trapping in the interface and/or border pre-existing defects and (ii) the creation of oxide defects and/or trapping in spatially deeper oxide states with an activation energy of ~80 meV. Notably, the adoption of different characterization methods highlights the distinct roles of these mechanisms. Moreover, the study demonstrates consistent behavior in permanent ΔV_TH degradation across V_Gstress levels using a power law model. Overall, these findings deepen the understanding of PBTI in SiC MOSFETs, providing insights for reliability optimization. Full article

The free radical trapping capacities of multiple pyranoanthocyanins in wine storage and ageing were theoretically explored by density functional theory (DFT) methods. Intramolecular hydrogen bonds were detected in all pyranoanthocyanins, and the planarity of the compounds worsened with an increasing dielectric constant in the environment. Solvents significantly influenced the reaction enthalpies; thus, the preferred thermodynamic mechanisms of the free radical scavenging reactions were modified in different phases. This study incorporates hydrogen atom transfer (HAT), proton loss (PL), electron transfer (ET) reactions, and demethylation (De) of methoxy group mechanisms. The three pyranoanthocyanins have the capacity to capture n₁+1 free radicals, where n₁ represents the number of methoxy groups. In the gas phase, they prefer employing the n₁-De-HAT mechanism on the guaiacyl moiety of the B ring, resulting in the formation of a stable quinone or a quinone radical to scavenge free radicals. In the benzene phase, pyranoanthocyanins trap free radicals via a PL−n₁−De−HAT mechanism. In the water phase, the targeted pyranoanthocyanins may dissociate in the form of carboxylate and tend to utilize the n₂−PL−n₁−De−ET mechanism, where n₂ and n₁ represent the number of phenolic groups and methoxy groups, respectively, facilitating multiple H⁺/e⁻ reactions. Full article

Diabetes mellitus (DM) has been recognized as an increased risk factor for cognitive impairment, known as diabetic encephalopathy (DE). Hyperglycemia and insulin resistance are the main initiators of DE, which is related to the accumulation of advanced glycation end products (AGEs). Potassium 2-(1-hydroxypentyl)-benzoate (PHPB), a derivative of 3-n-butylphthalide (dl-NBP), has emerged various properties including improved mitochondrial function, antioxidant, anti-neuroinflammation, and neuroprotective effects. The present study aimed to investigate the neuroprotective effect of PHPB against AGEs accumulation in type 2 diabetic KK-Ay mice model with DE and further explore the underlying mechanisms. The results showed that PHPB markedly ameliorated the spatial learning ability of KK-Ay mice in the Morris water maze and decreased AD-like pathologic changes (Tau hyperphosphorylation) in the cortex. Furthermore, we found that PHPB treatment significantly reduced AGEs generation via up-regulation of glyoxalase-1 (GLO1) protein and enhancement of methylglyoxal (MG) trapping, while there was no obvious difference in levels of glucose in plasma or brain, contents of total cholesterol (TC), triglycerides (TG), and plasma insulin. Also, PHPB treatment improved the insulin signaling pathway by increasing sirtuin1 (SIRT1) deacetylase activity and attenuated oxidative stress evidenced by elevating glucose-6-phosphate dehydrogenase (G-6-PD) protein expression, promoting the production of reduced glutathione (GSH) and reduced nicotinamide adenine dinucleotide phosphate (NADPH), restoring mitochondrial membrane potential, increasing adenosine triphosphate (ATP) generation, and reducing malondialdehyde (MDA) levels in the brain. Taken together, PHPB exhibited a beneficial effect on DE, which involved modulating the SIRT1/insulin signaling pathway and reducing oxidative stress by inhibiting the generation of AGEs. Full article

Optical synapse is the basic component for optical neuromorphic computing and is attracting great attention, mainly due to its great potential in many fields, such as image recognition, artificial intelligence and artificial visual perception systems. However, optical synapse with infrared (IR) response has rarely been reported. InAs nanowires (NWs) have a direct narrow bandgap and a large surface to volume ratio, making them a promising material for IR detection. Here, we demonstrate a near-infrared (NIR) (750 to 1550 nm) optical synapse for the first time based on a poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE))-coated InAs NW field-effect transistor (FET). The responsivity of the P(VDF-TrFE)-coated InAs NW FET reaches 839.3 A/W under 750 nm laser illumination, demonstrating the advantage of P(VDF-TrFE) coverage. The P(VDF-TrFE)-coated InAs NW device exhibits optical synaptic behaviors in response to NIR light pulses, including excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF) and a transformation from short-term plasticity (STP) to long-term plasticity (LTP). The working mechanism is attributed to the polarization effect in the ferroelectric P(VDF-TrFE) layer, which dominates the trapping and de-trapping characteristics of photogenerated holes. These findings have significant implications for the development of artificial neural networks. Full article

The Wireless Medium Access Control (WMAC) protocol functions by handling various data frames in order to forward them to neighbor sensor nodes. Under this circumstance, WMAC policies need secure data communication rules and intrusion detection procedures to safeguard the data from attackers. The existing secure Medium Access Control (MAC) policies provide expected and predictable practices against channel attackers. These security policies can be easily breached by any intelligent attacks or malicious actions. The proposed Wireless Interleaved Honeypot-Framing Model (WIHFM) newly implements distributed honeypot-based security mechanisms in each sensor node to act reactively against various attackers. The proposed WIHFM creates an optimal Wireless Sensor Network (WSN) channel model, Wireless Interleaved Honeypot Frames (WIHFs), secure hash-based random frame-interleaving principles, node-centric honeypot engines, and channel-covering techniques. Compared to various existing MAC security policies, the proposed model transforms unpredictable IHFs into legitimate frame sequences against channel attackers. Additionally, introducing WIHFs is a new-fangled approach for distributed WSNs. The successful development of the proposed WIHFM ensures resilient security standards and neighbor-based intrusion alert procedures for protecting MAC frames. Particularly, the proposed wireless honeypot methodology creates a novel idea of using honeypot frame traps against open wireless channel attacks. The development of a novel wireless honeypot traps deals with various challenges such as distributed honeypot management principles (node-centric honeypot, secretly interleaved-framing principles, and interleaving/de-interleaving procedures), dynamic network backbone management principles (On Demand Acyclic Connectivity model), and distributed attack isolation policies. This effort provides an effective wireless attack-trapping solution in dynamic WSNs. The simulation results show the advantage of the proposed WIHFM over the existing techniques such as Secure Zebra MAC (SZ-MAC), Blockchain-Assisted Secure-Routing Mechanism (BASR), and the Trust-Based Node Evaluation (TBNE) procedure. The experimental section confirms the proposed model attains a 10% to 14% superior performance compared to the existing techniques. Full article

Natural polymers have been investigated as part of the endeavors of green chemistry practice in the oil field. However, natural polymer studies are still preliminary. The current study examines okra’s (natural polymer) efficiency for polymer flooding, particularly in Kazakhstan. The evaluation targets the heavy oil trapped in carbonate reservoirs. SEM and FTIR were used to characterize morphology and chemical composition. A rheology study was conducted under different shear rates for three plausible concentrations: 1 wt.%, 2 wt.% and 5 wt.%. The core flooding was challenged by the low porosity and permeability of the core. The results showed that okra’s size is between 150–900 μm. The morphology can be described by rod-like structures with pores and staking as sheet structures. The FTIR confirmed that the solution contains a substantial amount of polysaccharides. During the rheology test, okra showed a proportional relationship between the concentration and viscosity increase, and an inversely proportional relationship with the shear rate. At reservoir temperature, the viscosity reduction was insignificant, which indicated good polymer stability. Okra showed shear-thinning behavior. It was fitted to the Ostwald–de Waele power-law model by a (90–99)% regression coefficient. The findings confirm okra’s pseudo-plasticity, and that it is proportional to the solution concentration. The incremental oil recovery was 7%. The flow was found to be restricted due to the mechanical entrapment resulting from the large molecule size and the low porosity–permeability of the system. This study proves that the dominating feature of natural polysaccharide derivatives is their applicability to moderate reservoir conditions. The current study is a positive attempt at natural polymer application in Kazakhstan and similar field conditions. Full article

In this paper, we demonstrate a device using a Ni/SiN/BN/p⁺-Si structure with improved performance in terms of a good ON/OFF ratio, excellent stability, and low power consumption when compared with single-layer Ni/SiN/p⁺-Si and Ni/BN/p⁺-Si devices. Its switching mechanism can be explained by trapping and de-trapping via nitride-related vacancies. We also reveal how higher nonlinearity and rectification ratio in a bilayer device is beneficial for enlarging the read margin in a cross-point array structure. In addition, we conduct a theoretical investigation for the interface charge accumulation/depletion in the SiN/BN layers that are responsible for defect creation at the interface and how this accounts for the improved switching characteristics. Full article

Malaria elimination urgently needs novel antimalarial therapies that transcend resistance, toxicity, and high costs. Our multicentric international collaborative team focuses on developing multistage antimalarials that exhibit novel mechanisms of action. Here, we describe the design, synthesis, and evaluation of a novel multistage antimalarial compound, ‘Calxinin’. A compound that consists of hydroxyethylamine (HEA) and trifluoromethyl-benzyl-piperazine. Calxinin exhibits potent inhibitory activity in the nanomolar range against the asexual blood stages of drug-sensitive (3D7), multidrug-resistant (Dd2), artemisinin-resistant (IPC4912), and fresh Kenyan field isolated Plasmodium falciparum strains. Calxinin treatment resulted in diminished maturation of parasite sexual precursor cells (gametocytes) accompanied by distorted parasite morphology. Further, in vitro liver-stage testing with a mouse model showed reduced parasite load at an IC₅₀ of 79 nM. A single dose (10 mg/kg) of Calxinin resulted in a 30% reduction in parasitemia in mice infected with a chloroquine-resistant strain of the rodent parasite P. berghei. The ex vivo ookinete inhibitory concentration within mosquito gut IC₅₀ was 150 nM. Cellular in vitro toxicity assays in the primary and immortalized human cell lines did not show cytotoxicity. A computational protein target identification pipeline identified a putative P. falciparum membrane protein (Pf3D7_1313500) involved in parasite calcium (Ca²⁺) homeostasis as a potential Calxinin target. This highly conserved protein is related to the family of transient receptor potential cation channels (TRP-ML). Target validation experiments showed that exposure of parasitized RBCs (pRBCs) to Calxinin induces a rapid release of intracellular Ca²⁺ from pRBCs; leaving de-calcinated parasites trapped in RBCs. Overall, we demonstrated that Calxinin is a promising antimalarial lead compound with a novel mechanism of action and with potential therapeutic, prophylactic, and transmission-blocking properties against parasites resistant to current antimalarials. Full article