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Supersymmetric extension of universal enveloping vertex algebras
No full textIn this paper, we study the construction of the supersymmetric extensions of vertex algebras. In particular, for N=n∈Z+, we show that the universal enveloping N=n SUSY vertex algebra of an N=n SUSY Lie conformal algebra can be extended to an N=n′>n SUSY vertex algebra. Additionally, we investigate various superconformal vectors which induce the same SUSY structure but distinct conformal weight decompositions of a vertex algebra.Y
An Analysis of Components and Enhancement Strategies for Advancing Memristive Neural Networks
No full textAdvancements in artificial intelligence (AI) and big data have highlighted the limitations of traditional von Neumann architectures, such as excessive power consumption and limited performance improvement with increasing parameter numbers. These challenges are significant for edge devices requiring higher energy and area efficiency. Recently, many reports on memristor-based neural networks (Mem-NN) using resistive switching memory have shown efficient computing performance with a low power requirement. Even further performance optimization can be made using engineering resistive switching mechanisms. Nevertheless, systematic reviews that address the circuit-to-material aspects of Mem-NNs, including their dedicated algorithms, remain limited. This review first categorizes the memristor-based neural networks into three components: pre-processing units, processing units, and learning algorithms. Then, the optimization methods to improve integration and operational reliability are discussed across materials, devices, circuits, and algorithms for each component. Furthermore, the review compares recent advancements in chip-level neuromorphic hardware with conventional systems, including graphic processing units. The ongoing challenges and future directions in the field are discussed, highlighting the research to enhance the functionality and reliability of Mem-NNs.N
Vertically integrated security devices with physically unclonable function and random number generation
No full textPhysically unclonable function (PUF) and random number generation (RNG) are commonly used security tools to protect sensitive information from external threats. This paper presents an approach to implement these tools based on three-dimensional monolithic and vertical integration, combining an overlying transistor for the PUF with an underlying transistor for RNG. The PUF was implemented using a polycrystalline silicon (poly-Si) thin-film transistor (TFT), while RNG was realized with a single crystalline silicon (sc-Si) field-effect transistor (FET). The poly- Si TFT for the PUF generates random keys across multiple devices, exhibiting variation of the threshold voltage due to different grain sizes and boundaries. This approach effectively doubles the encryption key capability by creating mirror bits in the source and drain of the poly-Si TFT. The sc-Si FET for RNG produces random numbers due to the stochastic behavior of iterative single transistor latching and unlatching, passing 15 NIST randomness tests. Integrating both security functions into a single chip can significantly reduce resource overhead in terms of hardware footprint and energy consumption, which is crucial in the era of mobile devices, edge computing, autonomous driving, and the Internet of Things.N
An innovative approach using CRISPR-ribonucleoprotein packaged in virus-like particles to generate genetically engineered mouse models
No full textGenetically engineered mouse models (GEMMs) are crucial for investigating disease mechanisms, developing therapeutic strategies, and advancing fundamental biological research. While CRISPR gene editing has greatly facilitated the creation of these models, existing techniques still present technical challenges and efficiency limitations. Here, we establish a CRISPR-VLP-induced targeted mutagenesis (CRISPR-VIM) strategy, enabling precise genome editing by co-culturing zygotes with virus-like particle (VLP)-delivered gene editing ribonucleoproteins (RNPs) without requiring physical manipulation or causing cellular damage. We generate Plin1- and Tyr-knockout mice through VLP-based SpCas9 or adenine base editor (ABE)/sgRNA RNPs and characterize their phenotype and germline transmission. Additionally, we demonstrate cytosine base editor (CBE)/sgRNA-based C-to-T substitution or SpCas9/sgRNA-based knock-in using VLPs. This method further simplifies and accelerates GEMM generation without specialized techniques or equipment. Consequently, the CRISPR-VIM method can facilitate mouse modeling and be applied in various research fields.Y
Measurements of the quantum geometric tensor in solids
No full textUnderstanding the geometric properties of quantum states and their implications in fundamental physical phenomena is a core aspect of contemporary physics. The quantum geometric tensor (QGT) is a central physical object in this regard, encoding complete information about the geometry of the quantum state. The imaginary part of the QGT is the well-known Berry curvature, which plays an integral role in the topological magnetoelectric and optoelectronic phenomena. The real part of the QGT is the quantum metric, whose importance has come to prominence recently, giving rise to a new set of quantum geometric phenomena such as anomalous Landau levels, flat band superfluidity, excitonic Lamb shifts and nonlinear Hall effect. Despite the central importance of the QGT, its experimental measurements have been restricted only to artificial two-level systems. Here, we develop a framework to measure the QGT in crystalline solids using polarization-, spin- and angle-resolved photoemission spectroscopy. Using this framework, we demonstrate the effective reconstruction of the QGT in the kagome metal CoSn, which hosts topological flat bands. Establishing this momentum- and energy-resolved spectroscopic probe of the QGT is poised to significantly advance our understanding of quantum geometric responses in a wide range of crystalline systems. Experiments that directly probe the quantum geometric tensor in solids have not been reported. Now, the quantum metric and spin Berry curvature-dual components of the quantum geometric tensor-have been simultaneously measured in reciprocal space.N
Age-Stratified Sex Differences in Heart Failure With Preserved Ejection Fraction Among Adult Hospitalizations
No full textBackgroundThere is evidence that heart failure with preserved ejection fraction (HFpEF)-related hospitalizations are increasing in the United States. However, there is a lack of knowledge about HFpEF-related hospitalizations among younger adults.ObjectiveThe aims of this study were to perform a retrospective analysis using the Nationwide Inpatient Sample and to examine age-stratified sex differences in the prevalence, correlates, and outcomes of HFpEF-related hospitalization across the adult life span.MethodUsing the Nationwide Inpatient Sample (2002-2014), patient and hospital characteristics were determined. Joinpoint regression was used to describe age-stratified sex differences in the annual average percent change of hospitalizations with HFpEF. Survey logistic regression was used to estimate adjusted odds ratios representing the association of sex with HFpEF-related hospitalization and in-hospital mortality.ResultsThere were 8 599 717 HFpEF-related hospitalizations (2.43% of all hospitalizations). Women represented the majority (5 459 422 [63.48%]) of HFpEF-related adult hospitalizations, compared with men (3 140 295 [36.52%]). Compared with men younger than 50 years, women within the same age group were 6% to 28% less likely to experience HFpEF-related hospitalization. Comorbidities such as hypertensive heart disease, renal disease, hypertension, obstructive sleep apnea, atrial fibrillation, obesity, anemia, and pulmonary edema explained a greater proportion of the risk of HFpEF-related hospitalization in adults younger than 50 years than in adults 50 years or older.ConclusionBefore the age of 50 years, women exhibit lower HFpEF-related hospitalization than men, a pattern that reverses with advancing age. Understanding and addressing the factors contributing to these sex-specific differences can have several potential implications for improving women's cardiovascular health.Y
Evaluation of physicochemical property changes in 3D-printed biodegradable medical devices under simulated oral physiological conditions
No full textBiodegradable medical devices undergo degradation following implantation, potentially leading to clinical failure. Consequently, it is necessary to assess the change in their properties post-implantation. However, a standardized method for the precise evaluation of the changes in their physicochemical properties is currently lacking. In this study, we aimed to establish precisely simulated oral physiological conditions (SOPCs) and investigate the physicochemical property changes to predict the performance alterations of biodegradable dental barrier membranes (BDBMs) following human implantation. We investigated changes in physicochemical properties of BDBM after exposure to SOPC for 24 weeks. When BDBM was exposed to SOPC for 24 weeks, there was a significant decrease in mass (-1.37%), molecular weight (-19.54%) and tensile load (-72.84%). Among the physicochemical properties, molecular weight decreased similarly after 24 weeks of implantation in rats (-15.78%) and after 24 weeks of exposure to SOPC (-19.54%). Changes in the physicochemical properties of BDBM in simulated in vitro oral conditions and in the in vivo environment were similar. Overall, the evaluation of physicochemical property changes after exposing BDBM to the proposed SOPC demonstrates novelty in its ability to accurately predict performance changes post-implantation. This approach may provide significant insights not only for the development of BDBM but also for various types of biodegradable medical devices.Y
Bridging theory and practice: the effects of experiential learning-based simulation training on technology integration competency among pre-service teachers
No full textWe investigated the impact of simulation training for technology integration (ST2I) on technology integration competency among pre-service teachers. A quasi-experiment was conducted in a 15-week undergraduate course with 45 pre-service teachers. Participants were assigned to experimental and control conditions. Those in the experimental condition received training with ST2I, whereas those in the control condition received conventional training. ST2I enabled the participants to experience, reflect, conceptualize, and act on three common technology integration scenarios in classrooms, following the experiential learning model designed by Kolb and Kolb (2009). The participants in the experimental group showed higher self-efficacy in using technologies for teaching and technological pedagogical knowledge than their counterparts in the control group. In addition, they showed a better understanding of technology integration in lesson plans and more effective approaches to engaging students through technology in self-recorded videos than the control group.N
Advancements in Uricase formulations: overcoming therapeutic challenges in enzyme replacement therapy
No full textBackgroundUricase-based enzyme replacement therapies have emerged as an effective treatment for refractory gout and tumor lysis syndrome. However, their clinical adoption has been hindered by challenges such as instability, rapid clearance, and immune responses. While formulations such as PEGylated uricase have demonstrated clinical efficacy, they are limited by the development of anti-PEG antibodies, which reduces their therapeutic effectiveness. Thus, innovative drug delivery strategies are required to address these limitations and increase the effectiveness of uricase therapies.Area coveredThis review provides a comprehensive overview of uricase as a therapeutic enzyme and discusses both the approved formulations and recent advances in drug delivery systems (DDS) aimed at overcoming key challenges. It focuses on nanoparticle-based and polymer-conjugated systems designed to improve stability, extend enzyme half-life, and reduce immunogenicity. Additionally, this review explores the use of lipid-based carriers, polymeric nanoparticles, and inorganic frameworks to optimize enzyme delivery, offering insights into their potential to increase pharmacokinetics and minimize immune responses.Expert opinionAlthough uricase-based therapies show considerable promise for refractory gout and tumor lysis syndrome, challenges related to their stability, pharmacokinetics, and immunogenicity persist. Advanced DDS strategies offer viable solutions by stabilizing enzymes, prolonging circulation, and mitigating immune reactions. Achieving therapeutic efficacy requires balancing immune evasion and enzymatic activity to ensure long-term effectiveness. Further innovations in DDS are essential to develop safer and more reliable uricase therapies, expand their clinical use, and address unmet patient needs.Y
Impact of More Than 1 Distal Anastomosis on the Same Territory in 3-Vessel Disease Patients
No full textBackground: Previous studies defined complete revascularization as the placement of at least 1 bypass graft to each diseased coronary territory. This study was conducted to evaluate whether putting more than 1 graft to each diseased coronary territory is beneficial for patients with 3-vessel disease (3VD) who underwent coronary artery bypass grafting (CABG). Methods: Among 1859 patients who underwent primary isolated CABG, 1008 patients (male-to-female ratio, 841:239; mean age, 67.0 ± 9.3 years) who underwent OPCAB for 3VD and in whom complete revascularization was achieved were retrospectively enrolled. Complete revascularization was defined as at least 1 graft to each coronary artery territory. The median follow-up duration was 86.6 months (interquartile range, 53.0-126.9). Results: A total of 829 patients (82.2%) had more than 3 distal anastomoses, whereas the other 179 patients had 3 distal anastomoses. Hypertension (n = 729; 72.3%) and diabetes (n = 556; 55.2%) were the most common comorbidities without any intergroup differences. The early mortality rate was 1.0% (n = 10). Late death occurred in 337 of 998 early survivors. Five- and 10-year all-cause mortality rates were 18.0% and 36.0%, respectively. Cumulative incidences of cardiac deaths were 5.2% and 9.2%, respectively. The inverse probability treatment weighting–adjusted multivariate analyses showed that having more than 3 distal anastomoses was associated with lower all-cause mortality and cardiac death (hazard ratio, 0.76 [95% CI, 0.57-0.99] and hazard ratio, 0.50 [95% CI, 0.31-0.83], respectively). Conclusions: Grafting more than 1 diseased vessel in each diseased coronary territory during CABG may be beneficial for patients with 3VD in terms of all-cause mortality and cardiac death.N