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The Dyakonov-Perel (DP) mechanism of spin relaxation has long been considered irrelevant in centrosymmetric systems since it was developed originally for noncentrosymmetric ones. We investigate whether this conventional understanding extends to the realm of orbital relaxation, which has recently attracted significant attention. Surprisingly, we find that orbital relaxation in centrosymmetric systems exhibits the DP-like behavior in the weak scattering regime. Moreover, the DP-like orbital relaxation can make the spin relaxation in centrosymmetric systems DP-like through the spin-orbit coupling. We also find that the DP-like orbital and spin relaxations are anisotropic even in materials with high crystal symmetry (such as face-centered cubic structure) and may depend on the orbital and spin nature of electron wave functions.
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The ETV6::ABL1 fusion defines a subgroup of myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions. We report a case of extramedullary involvement and leukemic transformation in myeloproliferative neoplasm (MPN), where ETV6::ABL1 was initially overlooked but later detected in the blast phase. ETV6::ABL1 burden was very low during the MPN phase but increased substantially during the blast phase. This correlation between ETV6::ABL1 burden and disease phenotype indicated that an immature leukemic clone is the sole carrier of ETV6::ABL1, suggesting that ETV6::ABL1 is not the primary driver of the MPN phase. Moreover, only the blast phase revealed somatic mutations in RUNX1 and STAG2, or complex karyotype, while the MPN phase revealed no molecular and cytogenetic abnormalities. Therefore, it remains uncertain whether the small clone of ETV6::ABL1 influenced the manifestation of MPN or if another underlying driver was responsible for the MPN phase, necessitating further research.
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CONTEXT.: Apocrine differentiation and androgen receptor (AR) positivity represent a specific subset of triple-negative breast cancer (TNBC) and are often considered potential prognostic or predictive factors. OBJECTIVE.: To evaluate the response of TNBC to neoadjuvant chemotherapy (NAC) and to assess the impact of apocrine morphology, AR status, Ki-67 labeling index (Ki-67LI), and tumor-infiltrating lymphocytes (TILs). DESIGN.: A total of 232 TNBC patients who underwent NAC followed by surgical resection in a single institute were analyzed. The study evaluated apocrine morphology and AR and Ki-67LI expression via immunohistochemistry from pre-NAC biopsy samples. Additionally, pre-NAC intratumoral TILs and stromal TILs (sTILs) were quantified from biopsies using a deep learning model. The response to NAC after surgery was assessed based on residual cancer burden. RESULTS.: Both apocrine morphology and high AR expression correlated with lower Ki-67LI (P < .001 for both). Apocrine morphology was associated with lower postoperative pathologic complete response (pCR) rates after NAC (P = .02), but the difference in TILs between TNBC cases with and without apocrine morphology was not statistically significant (P = .09 for sTILs). In contrast, AR expression did not significantly affect pCR (P = .13). Pre-NAC TILs strongly correlated with postoperative pCR in TNBCs without apocrine morphology (P < .001 for sTILs), whereas TNBC with apocrine morphology demonstrated an indeterminate trend (P = .82 for sTILs). CONCLUSIONS.: Although TIL counts did not vary significantly based on apocrine morphology, apocrine morphology itself was a more reliable predictor of NAC response than AR expression. Consequently, although apocrine morphology is a rare subtype of TNBC, its identification is clinically important.
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Analyzing the concentration of ions in aqueous solutions in real-time plays an important role in the fields of chemistry and biology. Traditional methods for measuring ion concentrations, such as concentration analysis by measuring electrical conductivity, inductively coupled plasma mass spectrometry, and ion chromatography, have been used in many research fields. However, these methods are limited in determining ion concentrations instantaneously. Fourier-transform infrared-attenuated total reflectance (ATR-FTIR) spectroscopy provides a new approach for determining ion concentrations in aqueous solutions. This allows for fast analysis without pretreatment and is scalable for real-time measurements. In this study, we present a method for measuring ion concentrations by examining ion-water interactions in the O-H stretching band of aqueous solutions using ATR-FTIR spectroscopy. Five aqueous solutions, namely LiCl + HCl, LiOH + HCl, LiOH, Li3PO4, and NaCl were used in the experiments and prepared at concentrations between 0.5-2 M. The ion concentrations in the prepared aqueous solutions were measured using ATR-FTIR spectroscopy. We observed that the difference in absorbance increased and decreased linearly with changes in concentration. The concentration of ions in the aqueous solution could be measured by validating the designed linear regression analysis function model. In this study, we proposed five linear regression analysis function models, all of which showed high coefficients of determination above 0.9, with the highest coefficient of determination reaching 0.9969. These results show that ATR-FTIR spectroscopy has the potential to be applied as a rapid and simple concentration analysis system.
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Introduction: This paper presents a comprehensive analysis of COVID-19 transmission dynamics using an infection network derived from epidemiological data in South Korea, covering the period from January 3, 2020, to July 11, 2021. The network illustrates infector-infectee relationships and provides invaluable insights for managing and mitigating the spread of the disease. However, significant missing data hinder conventional analysis of such networks from epidemiological surveillance. Methods: To address this challenge, this article suggests a novel approach for categorizing individuals into four distinct groups, based on the classification of their infector or infectee status as either traced or untraced cases among all confirmed cases. The study analyzes the changes in the infection networks among untraced and traced cases across five distinct periods. Results: The four types of cases emphasize the impact of various factors, such as the implementation of public health strategies and the emergence of novel COVID-19 variants, which contribute to the propagation of COVID-19 transmission. One of the key findings is the identification of notable transmission patterns in specific age groups, particularly in those aged 20-29, 40-69, and 0-9, based on the four type classifications. Furthermore, we develop a novel real-time indicator to assess the potential for infectious disease transmission more effectively. By analyzing the lengths of connected components, this indicator facilitates improved predictions and enables policymakers to proactively respond, thereby helping to mitigate the effects of the pandemic on global communities. Conclusion: This study offers a novel approach to categorizing COVID-19 cases, provides insights into transmission patterns, and introduces a real-time indicator for better assessment and management of the disease transmission, thereby supporting more effective public health interventions.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/transmisión , COVID-19/epidemiología , República de Corea/epidemiología , Adulto , Persona de Mediana Edad , Anciano , Adolescente , Niño , Trazado de Contacto , Preescolar , Lactante , Recién Nacido , Adulto Joven , Femenino , MasculinoRESUMEN
This study compared the performance of two commercial molecular assays, the STANDARD M10 Clostridioides difficile assay (M10) and the Xpert C. difficile assay (Xpert), for detecting toxigenic C. difficile in stool specimens. A total of 487 consecutive stool specimens submitted for routine C. difficile testing between June and November 2023 were included. Following routine testing using C. DIFF QUIK CHEK COMPLETE (QCC), M10 and Xpert were tested in parallel, alongside toxigenic culture (reference standard). Additionally, two-step algorithms, using QCC on the first step and either M10 or Xpert on the second step, were assessed. Both M10 and Xpert demonstrated a sensitivity and negative predictive value (NPV) of 100%. M10 exhibited significantly higher specificity and positive predictive value (PPV; 91.9% and 64.2%, respectively) than Xpert (90.3% and 59.8%, respectively). Both two-step algorithms showed a sensitivity and NPV of 98.4% and 99.8%, respectively. The specificity and PPV of the two-step algorithm using M10 (95.2% and 75.0%, respectively) were slightly higher than those of the one using Xpert (94.8% and 73.2%, respectively), without statistical significance. Receiver operating characteristic curve analysis, assessing the predictive ability of cycle threshold (Ct) values for the detection of free toxin, exhibited an area under the curve of 0.825 for M10 and 0.843 for Xpert. This indicates the utility of Ct values as predictors for the detection of free toxin in both assays. In conclusion, M10 proves to be an effective diagnostic tool with performance comparable to Xpert, whether utilized independently or as part of a two-step algorithm.
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Clostridioides difficile , Infecciones por Clostridium , Heces , Técnicas de Diagnóstico Molecular , Sensibilidad y Especificidad , Humanos , Clostridioides difficile/aislamiento & purificación , Clostridioides difficile/genética , Heces/microbiología , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/microbiología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Algoritmos , Toxinas Bacterianas/análisis , Toxinas Bacterianas/genética , Valor Predictivo de las PruebasRESUMEN
Episodic memory requires encoding the temporal structure of experience and relies on brain circuits in the medial temporal lobe, including the medial entorhinal cortex (MEC). Recent studies have identified MEC 'time cells', which fire at specific moments during interval timing tasks, collectively tiling the entire timing period. It has been hypothesized that MEC time cells could provide temporal information necessary for episodic memories, yet it remains unknown whether they display learning dynamics required for encoding different temporal contexts. To explore this, we developed a new behavioral paradigm requiring mice to distinguish temporal contexts. Combined with methods for cellular resolution calcium imaging, we found that MEC time cells display context-dependent neural activity that emerges with task learning. Through chemogenetic inactivation we found that MEC activity is necessary for learning of context-dependent interval timing behavior. Finally, we found evidence of a common circuit mechanism that could drive sequential activity of both time cells and spatially selective neurons in MEC. Our work suggests that the clock-like firing of MEC time cells can be modulated by learning, allowing the tracking of various temporal structures that emerge through experience.
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Corteza Entorrinal , Aprendizaje , Animales , Corteza Entorrinal/fisiología , Ratones , Masculino , Aprendizaje/fisiología , Neuronas/fisiología , Ratones Endogámicos C57BL , Percepción del Tiempo/fisiología , Memoria EpisódicaRESUMEN
Appropriate weight initialization settings, along with the ReLU activation function, have become cornerstones of modern deep learning, enabling the training and deployment of highly effective and efficient neural network models across diverse areas of artificial intelligence. The problem of "dying ReLU," where ReLU neurons become inactive and yield zero output, presents a significant challenge in the training of deep neural networks with ReLU activation function. Theoretical research and various methods have been introduced to address the problem. However, even with these methods and research, training remains challenging for extremely deep and narrow feedforward networks with ReLU activation function. In this paper, we propose a novel weight initialization method to address this issue. We establish several properties of our initial weight matrix and demonstrate how these properties enable the effective propagation of signal vectors. Through a series of experiments and comparisons with existing methods, we demonstrate the effectiveness of the novel initialization method.
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Aprendizaje Profundo , Redes Neurales de la Computación , Algoritmos , Inteligencia Artificial , Neuronas/fisiología , HumanosRESUMEN
Water evaporation-driven energy harvesting is an emerging mechanism for contributing to green energy production with low cost. Herein, we developed polyacrylonitrile (PAN) nanofiber-based evaporation-driven electricity generators (PEEGs) to confirm the feasibility of utilizing electrospun PAN nanofiber mats in an evaporation-driven energy harvesting system. However, PAN nanofiber mats require a support substrate to enhance its durability and stability when it is applied to an evaporation-driven energy generator, which could have additional effects on generation performance. Accordingly, various support substrates, including fiberglass, copper, stainless mesh, and fabric screen, were applied to PEEGs and examined to understand their potential impacts on electrical generation outputs. As a result, the PAN nanofiber mats were successfully converted to a hydrophilic material for an evaporation-driven generator by dip-coating them in nanocarbon black (NCB) solution. Furthermore, specific electrokinetic performance trends were investigated and the peak electricity outputs of Voc were recorded to be 150.8, 6.5, 2.4, and 215.9 mV, and Isc outputs were recorded to be 143.8, 60.5, 103.8, and 121.4 µA, from PEEGs with fiberglass, copper, stainless mesh, and fabric screen substrates, respectively. Therefore, the implications of this study would provide further perspectives on the developing evaporation-induced electricity devices based on nanofiber materials.
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The generation of current-induced torques through the spin Hall effect in Pt has been key to the development of spintronics. In prototypical ferromagnetic-metal/Pt devices, the characteristic length of the torque generation is known to be about 1 nm due to the short spin diffusion length of Pt. Here, we report the observation of a long-range current-induced torque in Ni/Pt bilayers. We demonstrate that when Ni is used as the ferromagnetic layer, the torque efficiency increases with the Pt thickness, even when it exceeds 10 nm. The torque efficiency is also enhanced by increasing the Ni thickness, providing evidence that the observed torque cannot be attributed to the spin Hall effect in the Pt layer. These findings, coupled with our semirealistic tight-binding calculations of the current-induced torque, suggest the possibility that the observed long-range torque is dominated by the orbital Hall effect in the Pt layer.
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OBJECTIVES: This study evaluates the HYDRASHIFT assay's effectiveness in mitigating daratumumab interference on serum protein tests during multiple myeloma (MM) treatment, aiming to ensure an accurate assessment of treatment response. METHODS: We analyzed 113 serum samples from 68 MM patients undergoing daratumumab treatment, employing both standard IF and the HYDRASHIFT assay. The assay's precision was determined through intra-day and inter-day variability assessments, while its specificity was verified using serum samples devoid of daratumumab. Comparative analysis of IF results, before and after the application of the HYDRASHIFT assay, facilitated the categorization of treatment responses in alignment with the International Myeloma Working Group's response criteria. RESULTS: The precision underscored the assay's consistent repeatability and reproducibility, successfully eliminating interference of daratumumab-induced Gκ bands. Specificity assessments demonstrated the assay's capability to distinguish daratumumab from both isatuximab and naturally occurring M-proteins. Of the analyzed cases, 91 exhibited successful migration of daratumumab-induced Gκ bands, thereby enhancing the accuracy of treatment response classification. The remaining 22 cases did not show a visible migration complex, likely due to the low concentration of daratumumab in the serum. These findings underscore the assay's critical role in distinguishing daratumumab from endogenous M-protein, particularly in samples with a single Gκ band on standard IF, where daratumumab and endogenous M-protein had co-migrated. CONCLUSIONS: The HYDRASHIFT assay demonstrates high precision, specificity, and utility in the accurate monitoring of treatment responses in MM patients receiving daratumumab. This assay represents a significant advancement in overcoming the diagnostic challenges posed by daratumumab interference.
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The novel HLA-B*13:191 allele was detected during the HLA typing for kidney transplantation.
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Antígenos HLA-B , Trasplante de Riñón , Humanos , Alelos , Antígenos HLA-B/genética , Genes MHC Clase I , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
Recently, topological responses of magnons have emerged as a central theme in magnetism and spintronics. However, resulting Hall responses are typically weak and infrequent, since, according to present understanding, they arise from effective spin-orbit couplings, which are weaker compared to the exchange energy. Here, by investigating transport properties of magnon orbital moments, we predict that the magnon orbital Nernst effect is an intrinsic characteristic of the honeycomb antiferromagnet and therefore, it manifests even in the absence of spin-orbit coupling. For the electric detection, we propose an experimental scheme based on the magnetoelectric effect. Our results break the conventional wisdom that the Hall transport of magnons requires spin-orbit coupling by predicting the magnon orbital Nernst effect in a system without it, which leads us to envision that our work initiates the intensive search for various magnon Hall effects in generic magnetic systems with no reliance on spin-orbit coupling.
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Nanosheet field-effect transistors (NSFETs) have attracted considerable attention for their potential to achieve improved performance and energy efficiency compared to traditional FinFETs. Here, we present a comprehensive investigation of core-insulator-embedded nanosheet field-effect transistors (C-NSFETs), focusing on their improved performance and device-to-device (D2D) variability compared to conventional NSFETs through three-dimensional device simulations. The C-NSFETs exhibit enhanced direct-current (DC) performance, characterized by a steeper subthreshold slope and reduced off-current, indicating better gate electrostatic controllability. Furthermore, the structural design of C-NSFETs enables to demonstrate a notable resilience against D2D variations in nanosheet thickness and doping concentration. In addition, we investigate the effects of interface traps in C-NSFETs, emphasizing the importance of thermal oxidation processes in the formation of core-insulating layers to maintain optimal device performance.
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All-Van der Waals (vdW)-material-based heterostructures with atomically sharp interfaces offer a versatile platform for high-performing spintronic functionalities at room temperature. One of the key components is vdW topological insulators (TIs), which can produce a strong spin-orbit-torque (SOT) through the spin-momentum locking of their topological surface state (TSS). However, the relatively low conductance of the TSS introduces a current leakage problem through the bulk states of the TI or the adjacent ferromagnetic metal layers, reducing the interfacial charge-to-spin conversion efficiency (qICS). Here, a vdW heterostructure is used consisting of atomically-thin layers of a bulk-insulating TI Sn-doped Bi1.1Sb0.9Te2S1 and a room-temperature ferromagnet Fe3GaTe2, to enhance the relative current ratio on the TSS up to ≈20%. The resulting qICS reaches ≈1.65 nm-1 and the critical current density Jc ≈0.9 × 106 Acm-2 at 300 K, surpassing the performance of TI-based and heavy-metal-based SOT devices. These findings demonstrate that an all-vdW heterostructure with thickness optimization offers a promising platform for efficient current-controlled magnetization switching at room temperature.
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Power generation technologies based on water movement and evaporation use water, which covers more than 70% of the Earth's surface and can also generate power from moisture in the air. Studies are conducted to diversify materials to increase power generation performance and validate energy generation mechanisms. In this study, a water-based generator was fabricated by coating cellulose acetate with carbon black. To optimize the generator, Fourier-transform infrared spectroscopy, specific surface area, zeta potential, particle size, and electrical performance analyses were conducted. The developed generator is a cylindrical generator with a diameter of 7.5 mm and length of 20 mm, which can generate a voltage of 0.15 V and current of 82 µA. Additionally, we analyzed the power generation performance using three factors (physical properties, cation effect, and evaporation environment) and proposed an energy generation mechanism. Furthermore, we developed an eco-friendly and low-cost generator using natural fibers with a simple manufacturing process. The proposed generator can contribute to the identification of energy generation mechanisms and is expected to be used as an alternative energy source in the future.
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The mammalian gut microbiota plays diverse and essential roles in modulating host physiology. Key mediators determining the outcome of the microbiota-host interactions are the small molecule metabolites produced by the gut microbiota. The liver is a major organ exposed to gut microbial metabolites, and it serves as the nexus for maintaining healthy interactions between the gut microbiota and the host. At the same time, the liver is the primary target of potentially harmful gut microbial metabolites. In this review, we provide an up-to-date list of gut microbial metabolites that have been identified to either increase or decrease host susceptibility to acetaminophen (APAP)-induced liver injury. The signaling pathways and molecular factors involved in the progression of APAP-induced hepatotoxicity are well-established, and we propose that the mouse model of APAP-induced hepatotoxicity serves as a model system for uncovering gut microbial metabolites with previously unknown functions. Furthermore, we envision that gut microbial metabolites identified to alter APAP-induced hepatotoxicity likely have broader implications in other liver diseases. SIGNIFICANCE STATEMENT: This review provides an overview of the role of the gut microbiota in modulating the host susceptibility to acetaminophen (APAP)-induced liver injury. It focuses on the roles of gut bacterial small molecule metabolites as mediators of the interaction between the gut microbiota and the liver. It also illustrates the utility of APAP-induced liver injury as a model to identify gut microbial metabolites with biological function.
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Acetaminofén , Enfermedad Hepática Inducida por Sustancias y Drogas , Microbioma Gastrointestinal , Acetaminofén/metabolismo , Acetaminofén/toxicidad , Acetaminofén/efectos adversos , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Animales , Humanos , Hígado/metabolismo , Hígado/efectos de los fármacos , Ratones , Susceptibilidad a Enfermedades , Analgésicos no Narcóticos/toxicidad , Analgésicos no Narcóticos/metabolismo , Analgésicos no Narcóticos/efectos adversosRESUMEN
Residual pure intralymphatic carcinoma (PIC) component only after neoadjuvant chemotherapy (NAC) is lymphovascular tumor emboli without invasive carcinoma and extremely rare form of residual tumor after NAC. Although several studies have been published, the prognostic influence of residual PIC component only had not been fully evaluated. This study aims to evaluate the clinicopathologic features and the prognostic value of residual PIC component only. We reviewed the 251 patients with no residual invasive carcinoma in breast after NAC and found 12 patients with residual PIC component only after NAC. Five cases were triple negative, 6 were HER2 positive, and 1 was estrogen receptor positive and HER2 negative. The extent of PIC component ranged from 0.18 to 50.00 mm. The detailed microscopic PIC component findings did not significantly correlate with regional lymph node metastasis, local recurrence, or distant metastasis (p > 0.05). In multivariate survival analysis, the presence of lymph node metastasis and pretreatment ki-67 labeling index more than 50 % was statistically associated with greater risk of relapse [Cox proportional hazards ratio (HR) = 3.236, 95 % confidence interval (CI), 1.461-7.280, p = 0.004; HR = 3.046, 95 % CI, 1.421-6.529, p = 0.004, respectively) and residual PIC component only tended to be associated with greater risk of relapse (HR = 2.378, 95 % CI, 0.853-6.631; p = 0.098), but not reached to statistically significance. In patients without lymph node metastasis, the presence of residual PIC component only was associated with worse disease-free survival (p = 0.004). Although the number of published studies still limited, residual residual PIC component only after NAC is associated with poor outcome, and it should not be considered as pathological complete response.
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Neoplasias de la Mama , Carcinoma , Humanos , Femenino , Metástasis Linfática , Terapia Neoadyuvante , Recurrencia Local de Neoplasia , Pronóstico , Respuesta Patológica Completa , Recurrencia , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Neoplasia Residual , Estudios RetrospectivosRESUMEN
Episodic memory requires encoding the temporal structure of experience and relies on brain circuits in the medial temporal lobe, including the medial entorhinal cortex (MEC). Recent studies have identified MEC 'time cells', which fire at specific moments during interval timing tasks, collectively tiling the entire timing period. It has been hypothesized that MEC time cells could provide temporal information necessary for episodic memories, yet it remains unknown whether MEC time cells display learning dynamics required for encoding different temporal contexts. To explore this, we developed a novel behavioral paradigm that requires distinguishing temporal contexts. Combined with methods for cellular resolution calcium imaging, we find that MEC time cells display context-dependent neural activity that emerges with task learning. Through chemogenetic inactivation we find that MEC activity is necessary for learning of context-dependent interval timing behavior. Finally, we find evidence of a common circuit mechanism that could drive sequential activity of both time cells and spatially selective neurons in MEC. Our work suggests that the clock-like firing of MEC time cells can be modulated by learning, allowing the tracking of various temporal structures that emerge through experience.