Search Results (204)

Silicon carbide (SiC) MOSFETs are critical for next-generation power electronics, yet their reliability is challenged by alternating-current Bias Temperature Instability (AC BTI). While charge trapping and Recombination-Enhanced Defect Reaction (REDR) are known degradation pathways, the specific role of gate oxide thickness in determining the dominant mechanism remains unclear. This study investigates the degradation behaviors of SiC MOSFETs with varying oxide thicknesses under 150 kHz Dynamic Gate Stress. By maintaining a constant electric field, we decouple the effects of oxide thickness using high-frequency C-V, quasi-static gate current (I_GS) characteristics, and transconductance analysis. Results reveal that thin-oxide devices exhibit parallel C-V shifts and stable transconductance, indicating degradation driven by deep-level charge trapping. Conversely, thick-oxide devices display significant C-V stretch-out, negligible I_GS peak shifts, and severe transconductance degradation, accompanied by irreversible threshold voltage drift. We conclude that despite identical electric fields, the higher driving voltages in thick-oxide devices trigger severe interface state generation consistent with the REDR model, whereas thin-oxide devices are dominated by bulk oxide trapping. These findings highlight the necessity of thickness-dependent optimization strategies for SiC power devices. Full article

Reliability assessment of semiconductor devices increasingly requires the consideration of multiple degradation mechanisms acting simultaneously over long stress durations. Conventional lifetime qualification and prediction approaches rely on simplified assumptions that can obscure the interpretation of measured degradation data and lead to large uncertainty when extrapolated over many orders of magnitude in time. A consistent analytical framework is therefore required to relate measured degradation behavior to meaningful reliability metrics. This work presents a general framework for semiconductor device reliability that is consistent with established reliability theory and explicitly accommodates multiple competing degradation mechanisms, consistent with modern JEDEC reliability standards. The framework presented here separates physical degradation processes from analytical representations used to interpret experimental data, allowing the effect of independent mechanisms to be combined without imposing an implied physical model. Degradation behaviors exhibiting sublinear time dependence, which are commonly observed across device technologies, are discussed within this context. We show that common data interpretation practices can introduce systematic errors when ssublinearkinetics are present, particularly regarding lifetime extrapolation. A reformulated analytical representation is introduced that improves clarity and robustness in lifetime extraction while remaining fully compatible with standard reliability theory. This framework supports more consistent reliability assessment and more credible lifetime prediction across materials, devices, and operating conditions. Full article

Cooperation between neutrophils and macrophages is essential to innate immunity. Though they share origins, their distinct roles make them complementary in fighting pathogens and regulating inflammation. However, dysregulation can drive chronic inflammation and autoimmune disease, making therapeutic targeting highly challenging. Broad suppression of these cells is risky; instead, precision strategies are needed to modulate their dual roles in promoting and resolving inflammation. Aging further complicates this balance, as impaired neutrophil and macrophage functions—alongside microbiota alterations—contribute to inflammaging and immune dysfunction. Recent advances in technology offer opportunities to explore these interactions in physiologically relevant contexts, paving the way for targeted interventions that restore immune homeostasis without compromising defense mechanisms. This article highlights the need for nuanced approaches to harness neutrophil–macrophage cooperation for therapeutic benefit. Full article

Background: Hirschsprung disease (HD) is associated with substantial postoperative morbidity, particularly due to Hirschsprung-associated enterocolitis (HAEC), despite definitive surgical treatment. Postoperative outcomes may vary according to the length of the aganglionic segment and the surgical technique used, and optimal management of recurrent HAEC remains a significant clinical challenge. Methods: The medical records of patients who underwent corrective surgery for HD between 2011 and 2023 were retrospectively reviewed. Demographic characteristics, disease segment length, surgical technique, postoperative complications, and HAEC episodes were recorded. HAEC diagnosis and follow-up assessments were conducted in accordance with the Delphi criteria. Patients with recurrent HAEC and obstructive symptoms refractory to standard conservative management were evaluated for botulinum toxin injection (BTI). Results: A total of 72 patients were included in the study. The majority of the patients were male (83.3%), with a mean age at diagnosis of 11 months. The Duhamel procedure was the most frequently performed surgical technique. Although the rate of anastomotic leakage was greater in patients who underwent the Swenson procedure compared with the Duhamel group, this difference did not reach statistical significance when the appropriate statistical methods were used because the small sample size. No significant difference in the incidence of HAEC was observed among the different surgical techniques. BTI was administered to 13 patients, and regression of enterocolitis episodes according to the Delphi criteria was observed in 11 patients (84.6%). Most postoperative complications are observed in patients with long-segment Hirschsprung disease. Conclusions: Postoperative complications and HAEC remain major clinical challenges in the management of Hirschsprung disease, particularly in patients with long-segment involvement. Although the surgical technique may influence certain complication rates, HAEC appears to be a multifactorial condition. Botulinum toxin injection may serve as a supportive treatment option in selected patients with refractory HAEC; however, prospective controlled studies are needed to further clarify its role. Full article

Microorganisms residing on the skin play a crucial role in maintaining both the integrity of the skin barrier and immune function. This study examined the effects of culture supernatants from canine-derived Bifidobacterium animalis subsp. lactis DS008 on canine keratinocytes in vitro. To induce cytokine production, canine progenitor epidermal keratinocytes (CPEK) were indirectly co-cultured with Malassezia pachydermatis using an insert well system to prevent direct cell-to-yeast contact, and CPEK were supplemented with 0.1%, 1%, and 10% of DS008 supernatants. mRNA expression levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-13, thymic stromal lymphopoietin (TSLP), IL-31, and keratin 10 were analyzed by real-time PCR. The protein concentrations of TSLP and IL-31 were measured by ELISA. Additionally, DS008 supernatants were applied to reconstructed canine epidermis (RCE) models exposed to lipopolysaccharide to evaluate changes in epidermal architecture. Treatment with DS008 supernatants showed significant reductions in mRNA expression of TNF-α, IL-13, TSLP, and IL-31, as well as decreased protein levels of TSLP and IL-31. Furthermore, keratin 10 mRNA expression was significantly increased, and RCE analysis demonstrated that DS008 supernatants ameliorated stratum corneum deformation. These findings suggest that postbiotics derived from canine-derived Bifidobacterium animalis subsp. lactis DS008 is a potential candidate with anti-inflammatory properties. Full article

The continued downscaling of transistors has exacerbated aging mechanisms such as bias temperature instability (BTI) and hot-carrier injection (HCI), posing significant reliability challenges for nanoscale integrated circuits. These effects are particularly critical to flip-flops operating at low supply voltages, which are essential for ultra-low-power applications including the Internet of Things (IoT) and biomedical implants. In this work, we address the aging issue in low-voltage Split-Controlled Flip-Flops (SCFFs) by proposing a novel transistor-level mitigation technique specifically tailored to this architecture within a domestic 14 nm process library. Through a detailed analysis of aging-critical transistors, three targeted enhancement strategies are introduced. Simulation results demonstrate that the improved SCFF achieves more than a 60% reduction in PMOS threshold voltage degradation and a 40% reduction in timing delay, while maintaining robust operation at a supply voltage as low as 0.4 V. These results highlight the effectiveness of the proposed approach in mitigating aging effects and enhancing reliability under low-voltage operation. Full article

Silicon carbide (SiC) MOSFETs, as one of the representative power electronic devices, have faced reliability challenges due to threshold voltage (V_th) instability under dynamic gate stress. To explore the underlying mechanisms, this work investigates 4H-SiC MOS structures (P-MOS and N-MOS) under AC bias temperature instability (AC BTI) stress, utilizing a laser to generate minority carriers and simulate realistic switching conditions. Through combined capacitance–voltage (C-V) and gate current–voltage (J_g-V_g) characterizations on P-MOS and N-MOS devices before and after degradation at different temperatures, we reveal a critical temperature dependence in defect interactions. At room temperature, degradation is dominated by electron trapping in shallow interface states and near-interface traps (NITs). In contrast, high-temperature stress activates charge exchange with deep-level, slow states. Notably, a positive V_FB shift is consistently observed in both N-MOS and P-MOS devices under AC stress, confirming that electron trapping is the dominant cause of the commonly observed positive V_th shift in SiC MOSFETs. These findings clarify the distinct defect-mediated mechanisms governing dynamic V_th instability in SiC devices, providing fundamental insights for interface engineering and reliability assessment. Full article

This work examines resistance drift in FPGA I/O paths subjected to combined electrical and thermal stress, using a Xilinx Spartan-6 device as a representative platform. A multiplexed measurement approach was employed, in which multiple I/O pins were externally shorted and sequentially activated, enabling precise tracking of voltage, current, and effective series resistance over time, under controlled bias conditions. Two accelerated stress modes were investigated: high-temperature dwell in the range of 80–120 °C and thermal cycling between 80 and 140 °C. Both stress modes exhibited similar sub-linear (power-law) time dependence on resistance change, indicating cumulative degradation behavior. However, Arrhenius analysis revealed a strong contrast in effective activation energy: approximately 0.62 eV for high-temperature dwell and approximately 1.3 eV for thermal cycling. This divergence indicates that distinct physical mechanisms dominate under each stress regime. The lower activation energy is consistent with electrically and thermally driven on-die degradation within the FPGA I/O macro, including bias-related aging of output drivers and pad-level structures. In contrast, the higher activation energy observed under thermal cycling is characteristic of diffusion- and creep-dominated thermo-mechanical damage in package-level interconnects, such as solder joints. These findings demonstrate that resistance-based monitoring of FPGA I/O paths can discriminate between device-dominated and package-dominated aging mechanisms, providing a practical foundation for reliability assessment and self-monitoring methodologies in complex electronic systems. Full article

Background: Chronic post-stroke spasticity often limits gait despite best-practice botulinum-toxin intramuscular injections (BTIs), whose benefit is constrained by short duration, dose ceilings, and tachyphylaxis. Cryoneurolysis (CNL) induces a reversible axonotmesis with preserved endoneurium, potentially providing longer tone reduction with fewer adverse effects, but its impact on whole-gait quality and its compatibility with implanted functional electrical stimulation (FES) remain poorly documented. Case presentation: A 43-year-old man, 12 years after right middle cerebral artery stroke, walked independently with an implanted common peroneal FES system but complained of effortful gait with left-knee “locking” and drop foot without FES. Multiple BTI series to triceps surae and quadriceps yielded only transient benefit. Two ultrasound-guided CNL sessions targeted tibial (soleus, medial gastrocnemius) and femoral (rectus femoris, vastus intermedius) motor branches. Quantitative gait analysis and fine-wire electromyography (EMG) were performed at baseline, 6 weeks after each CNL, and at 6 months, with and without FES. CNL produced immediate and sustained reductions in triceps surae and quadriceps overactivity, resolution of genu recurvatum, normalization of stiff-knee gait, improved ankle dorsiflexion, and increased swing phase knee flexion (>50°). Gait Deviation Index rose from 69 to 80 and Gillette Gait Index decreased by more than 50%, with preserved strength and without adverse events. Conclusions: Targeted, sequential CNL of tibial and femoral motor branches can safely deliver durable, clinically meaningful gait improvements when BTI has reached its ceiling and can act synergistically with implanted FES. Quantitative gait analysis and EMG sharpen clinical decision-making in spasticity management. Full article

Background and Objectives: Corneal opacity is the fifth global cause of blindness and moderate-to-severe visual impairment due to scar tissue formation. The purpose of this study is to provide an integrated overview of the current state of corneal engineering strategies focused on the comparison with healthy corneas. It aims to identify engineering strategies that would result in functional corneas, providing real alternatives to donor corneal transplants. Materials and Methods: systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and according to the protocol with the ID: CRD420250654641 at the PROSPERO database. The focus question, prompted by considering the shortage of human corneal grafts, was: what is the performance of bioengineered corneal grafts in experimental animal models when compared with healthy eyes in the restoration of corneal anatomy and function? Results: Incorporating human corneal epithelial cells w/ or w/o human corneal stromal stem cells into a gelatin methacrylate and polyethylene glycol diacrylate matrix emerges as the leading option for epithelial layer regeneration. Human and bovine decellularized corneas, porcine corneal ECM in Gelatin methacrylate, dual layered collagen vitrigel and tissue-engineered human anterior hemi-corneas have shown promise for simultaneous regeneration of the corneal stromal and epithelial layers. Corneal stromal tissue regeneration could be positively impacted by transplantation with grafts derived from aligned self-lifting analogous tissue equivalents and collagen-based hydrogels. Finally, scaffolds of silk fibroin and human purified type I collagen represent promising approaches for corneal endothelial regeneration, though their effectiveness is contingent upon integration with endothelial cells. Conclusions: Collectively, these findings contribute to the growing body of evidence supporting the potential of tissue-engineered corneal substitutes as viable therapeutic options for corneal blindness and vision impairment. Assessing the optical and functional properties of the regenerated cornea should be a cornerstone in all studies aiming to evaluate their clinical effectiveness. Full article

Background and Objectives: The aim of this study is to employ quantitative proteomics to elucidate the molecular mechanism and signaling pathways modulated by plasma rich in growth factors (PRGF) in a murine model of geographic atrophy (GA)-like retinal degeneration. Materials and Methods: C57BL/6J mice were used as a model GA-like retinal degeneration by a single systemic NaIO₃ administration. Animals were divided into three groups: Control (PBS), Disease (NaIO₃ + PBS), and PRGF-treated (NaIO₃ + PRGF). After 7 days, retinas and retinal pigment epithelium were collected for proteomic analysis. Proteins were extracted, digested using the FASP method, and analyzed by Data-Independent Acquisition (DIA-PASEF) mass spectrometry; data were processed with DIA-NN and statistically analyzed with Perseus. Functional pathway analysis was performed using Ingenuity Pathway Analysis. Results: A total of 6511 proteins were identified. The Disease model showed the expected deregulation of pathways related to oxidative stress, inflammation, and fibrosis. Comparison between the PRGF and Control groups showed that PRGF significantly reduced oxidative and cellular stress proteins/pathways. In the same way, when PRGF and Disease groups were compared, PRGF treatment showed a significant reduction in pathways associated with inflammation, oxidative stress, and cellular stress. PRGF also activated several homeostatic pathways not only related to neuroprotective pathways but also with the lipid deposition (drusen) reduction. All these results suggest that PRGF treatment exerts a protective effect against NaIO₃-induced retinal damage. Conclusions: These findings suggest that PRGF effectively mitigates the degenerative effects of NaIO₃ by activating specific protective and compensatory signaling pathways in the retina. PRGF is indicated as a promising new therapeutic option for ameliorating age-related macular degeneration progression. Full article

The functional landscape of the skin microbiome is largely defined by dominant genera such as Cutibacterium and Staphylococcus, whereas rare commensals remain poorly understood. In this study, we identified Rothia kristinae BF00107, a skin-resident strain with a complete pantothenate biosynthesis pathway, as a novel postbiotic candidate with distinct dermatological benefits. BF00107 fermentation filtrate suppressed pro-inflammatory cytokines (IL-1β and TNF-α) in keratinocytes and restored extracellular matrix homeostasis in UVB-irradiated fibroblasts by upregulating COL1A1 expression and reducing MMP-1 levels. Consistent with the observed phenotypes, transcriptomic profiling revealed a strain-specific signature characterized by downregulation and upregulation of the expression of inflammatory mediators and barrier- and ECM-associated genes, respectively. Comparative genomics and metabolite profiling confirmed BF00107 as a unique high-pantothenate producer. Supplementation with pantothenic acid reproduced the anti-inflammatory and barrier-supporting effects of the strain, confirming its role as a key effector metabolite. Furthermore, BF00107 passed standard safety assessments, including the Human Repeat Insult Patch Test (HRIPT), Ames, and irritation tests, supporting its suitability for human applications. These findings establish the pantothenate-producing R. kristinae BF00107 as the first functionally validated Rothia strain with anti-inflammatory and photoaging-protective properties. This study expands the functional scope of the skin microbiome and highlights rare commensals as valuable reservoirs for safe, strain-specific postbiotic development. Full article

This work investigates bias-temperature instability (BTI) in 1700 V 4H-SiC MOSFETs under realistic 1 MHz switching conditions with simultaneous gate and drain stress. Threshold-voltage measurements reveal that the degradation does not follow the classical Reaction–Diffusion behavior typically assumed for silicon devices. Instead, the power-law exponent n shows a clear increase at the largest negative gate bias (−10 V), indicating a field-driven trap-generation mechanism. Temperature-dependent stress tests further show a negative activation energy (−0.466 eV), consistent with degradation accelerating at lower temperatures due to suppressed detrapping. The results demonstrate that conventional silicon BTI models cannot be directly applied to SiC technologies and that fixed-n lifetime extrapolation leads to significant errors. A bias-dependent, field-driven framework for estimating time-to-failure is proposed, offering more accurate and practical reliability prediction for high-power SiC converter applications. Full article

In Brazil, public health programs have relied predominantly on chemical insecticides to control Aedes aegypti, Anopheles spp., Culex quinquefasciatus, triatomines, and phlebotomines. Rising vector-borne disease incidence and insecticide resistance (IR) call for a critical appraisal of historical and current control practices. This literature review compiles secondary data produced from 1901 to 2024 obtained from Medline/PubMed, Google Scholar, and governmental notes and reports. Brazil’s vector control progressed from organochlorines (e.g., DDT) to organophosphates, carbamates, pyrethroids, insect growth regulators, microbial larvicides (Bti and Lsp), spinosad, and recently formulations with dual active-ingredient. Ae. aegypti showed widespread resistance to temephos and pyrethroids, decreased susceptibility to pyriproxyfen, and no documented Bti resistance. Anopheles spp. exhibited low to moderate resistance to pyrethroids. Cx. quinquefasciatus resistance is likely influenced by collateral exposure from Aedes control and domestic use. Regarding triatomines and phlebotomines, there was a predominant reliance on pyrethroids; most studies indicate their susceptibility to these compounds. In short, Brazil’s century-long, insecticide-centric strategy has delivered episodic gains but fostered Aedes aegypti resistance. For other species, for which there is no dedicated program for a long period, data on resistance are scarce or nonexistent. Sustainable progress requires strengthened, nationwide IR surveillance and entomological mapping to coordinate cross-program actions. Full article