Modeling Multi-wavelength Pulse Profiles of Millisecond Pulsar PSR B1821-24

PSR B1821$-$24 is a solitary millisecond pulsar (MSP) which radiates multi-wavelength pulsed photons. It has complex radio, X-ray and $\gamma$-ray pulse profiles with distinct peak phase-separations that challenge the traditional caustic emission models. Using the single-pole annular gap model with suitable magnetic inclination angle ($\alpha=40^\circ$) and viewing angle ($\zeta=75^\circ$), we managed to reproduce its pulse profiles of three wavebands. It is found that the middle radio peak is originated from the core gap region at high altitudes, and the other two radio peaks are originated from the annular gap region at relatively low altitudes. Two peaks of both X-ray and $\gamma$-ray wavebands are fundamentally originated from annular gap region, while the $\gamma$-ray emission generated from the core gap region contributes somewhat to the first $\gamma$-ray peak. Precisely reproducing the multi-wavelength pulse profiles of PSR B1821$-$24 enables us to understand emission regions of distinct wavebands and justify pulsar emission models.Comment: Accepted for publication in Ap

Comparison of Lithium-Ion Anode Materials Using an Experimentally Verified Physics-Based Electrochemical Model

Researchers are in search of parameters inside Li-ion batteries that can be utilized to control their external behavior. Physics-based electrochemical model could bridge the gap between Li+ transportation and distribution inside battery and battery performance outside. In this paper, two commercially available Li-ion anode materials: graphite and Lithium titanate (Li4Ti5O12 or LTO) were selected and a physics-based electrochemical model was developed based on half-cell assembly and testing. It is found that LTO has a smaller diffusion coefficient (Ds) than graphite, which causes a larger overpotential, leading to a smaller capacity utilization and, correspondingly, a shorter duration of constant current charge or discharge. However, in large current applications, LTO performs better than graphite because its effective particle radius decreases with increasing current, leading to enhanced diffusion. In addition, LTO has a higher activation overpotential in its side reactions; its degradation rate is expected to be much smaller than graphite, indicating a longer life span

Conversational Recommender System and Large Language Model Are Made for Each Other in E-commerce Pre-sales Dialogue

E-commerce pre-sales dialogue aims to understand and elicit user needs and preferences for the items they are seeking so as to provide appropriate recommendations. Conversational recommender systems (CRSs) learn user representation and provide accurate recommendations based on dialogue context, but rely on external knowledge. Large language models (LLMs) generate responses that mimic pre-sales dialogues after fine-tuning, but lack domain-specific knowledge for accurate recommendations. Intuitively, the strengths of LLM and CRS in E-commerce pre-sales dialogues are complementary, yet no previous work has explored this. This paper investigates the effectiveness of combining LLM and CRS in E-commerce pre-sales dialogues, proposing two collaboration methods: CRS assisting LLM and LLM assisting CRS. We conduct extensive experiments on a real-world dataset of Ecommerce pre-sales dialogues. We analyze the impact of two collaborative approaches with two CRSs and two LLMs on four tasks of Ecommerce pre-sales dialogue. We find that collaborations between CRS and LLM can be very effective in some cases.Comment: EMNLP 2023 Finding

New Method for Determination of Residual Strength Parameters and Critical Damage Value

Residual strength and critical damage parameters are worthy to evaluate the stability of engineered rock masses. In this paper, new thinking, repeated load test on a single specimen was proposed to measure the residual strength of the rock. And author proposed to modify the critical damage value based on residual constitutive energy. The test results showed that: (1) the residual strength of rock is mainly controlled by the confining pressure, without a clear relationship with the confining pressure and stress path of the initial loading failure. (2) The residual strength parameters of the rock specimens under repeated loading test are consistent with the conventional triaxial test. Most importantly, the proposed method is relatively less dispersion, cheap, reliable, and time-saving. (3) The corrected critical damage value was reasonable. Relevant test methods can provide a useful reference for the determination of residual strength parameters and critical damage value

Pressure-Controlled Motion of Single Polymers through Solid-State Nanopores

Voltage-biased solid-state nanopores are well established in their ability to detect and characterize single polymers, such as DNA, in electrolytes. The addition of a pressure gradient across the nanopore yields a second molecular driving force that provides new freedom for studying molecules in nanopores. In this work, we show that opposing pressure and voltage bias enables nanopores to detect and resolve very short DNA molecules, as well as to detect near-neutral polymers.Engineering and Applied SciencesPhysic

Risk Prioritization and Management in Gas Stations by using Fuzzy AHP and IPA Analysis

1107-1116Gasoline industry is the main pillar of Pakistan’s economy and is of immense importance. This industry is confronted by diverse risks which significantly affect its performance resulting in decreased economic contribution. On the other side, published literature merely analyzes this industry and suggests directions to improve it. Thus, this study is a kickoff step in this regard, and its purpose is to study the relationship between risk factors, importance, and performance of gasoline industry, which is based on questionnaire data collected from three districts, viz., Gujranwala, Gujrat and Sialkot of Punjab, Pakistan. In total, 159 completed questionnaires were collected having consistency ratio (CR) less than 0.1. Acquired stats were investigated using the latest techniques of multi-criteria decision making routines, viz., fuzzy analytic hierarchy process (Fuzzy AHP) and importance performance analysis (IPA) software Expert Choice 2000. Among the five main risk types faced by gasoline industry, transportation / tanker unloading (importance, 0.467: rank, 1) was the most, whereas, the least significant factor was miscellaneous category (importance, 0.049: rank, 5). Moreover, the most significant factor which showed high importance with high performance was driving carelessness / accidents (importance, 0.278; performance, 3.32), high importance with low performance was uncontrolled vapor released (importance, 0.087; performance, 2.53), low importance with low performance was fire / explosion (importance, 0.021; performance, 2.66) and low importance with high performance was overfill / crossover (importance, 0.027; performance, 4.11). Thus, this work identifies, prioritizes and highlights the areas where improvement is needed to encounter risk and increase quality function development of gas stations

Purification and Functional Characterization of a Histone H3-Lysine 4-Specific Methyltransferase

AbstractMethylation of histone H3 at lysine 9 by SUV39H1 and subsequent recruitment of the heterochromatin protein HP1 has recently been linked to gene silencing. In addition to lysine 9, histone H3 methylation also occurs at lysines 4, 27, and 36. Here, we report the purification, molecular identification, and functional characterization of an H3-lysine 4-specific methyltransferase (H3-K4-HMTase), SET7. We demonstrate that SET7 methylates H3-K4 in vitro and in vivo. In addition, we found that methylation of H3-K4 and H3-K9 inhibit each other. Furthermore, H3-K4 and H3-K9 methylation by SET7 and SUV39H1, respectively, have differential effects on subsequent histone acetylation by p300. Thus, our study provides a molecular explanation to the differential effects of H3-K4 and H3-K9 methylation on transcription

Methylation of H3-Lysine 79 Is Mediated by a New Family of HMTases without a SET Domain

AbstractThe N-terminal tails of core histones are subjected to multiple covalent modifications, including acetylation, methylation, and phosphorylation [1]. Similar to acetylation, histone methylation has emerged as an important player in regulating chromatin dynamics and gene activity [2–4]. Histone methylation occurs on arginine and lysine residues and is catalyzed by two families of proteins, the protein arginine methyltransferase family and the SET-domain-containing methyltransferase family [3]. Here, we report that lysine 79 (K79) of H3, located in the globular domain, can be methylated. K79 methylation occurs in a variety of organisms ranging from yeast to human. In budding yeast, K79 methylation is mediated by the silencing protein DOT1. Consistent with conservation of K79 methylation, DOT1 homologs can be found in a variety of eukaryotic organisms. We identified a human DOT1-like (DOT1L) protein and demonstrated that this protein possesses intrinsic H3-K79-specific histone methyltransferase (HMTase) activity in vitro and in vivo. Furthermore, we found that K79 methylation level is regulated throughout the cell cycle. Thus, our studies reveal a new methylation site and define a novel family of histone lysine methyltransferase