83 research outputs found

    Capacity and Optimum Signal Constellations for VLC Systems

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    In this paper, the capacity of the point-to-point VLC system is investigated by means of functional analysis subject to amplitude constraint and average intensity constraint. It is proved that the capacity can be achieved by a unique probability density function (PDF). The necessary and sufficient condition for the capacity-achieving PDF is derived by the functional optimization theorem. Moreover, the capacity-achieving PDF is proved to be discrete and finite. Based on these properties, the capacity-achieving constellation optimization problems under amplitude constraint and average intensity constraint is formulated and an algorithm is proposed to solve the corresponding problem. To apply simple adaptive modulation in practical VLC systems, constellation optimization problem subject to an additional equal probability constraint is formulated and solved by maximizing the mutual information as well

    Breaking Language Barriers in Multilingual Mathematical Reasoning: Insights and Observations

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    Existing research predominantly focuses on developing powerful language learning models (LLMs) for mathematical reasoning within monolingual languages, with few explorations in preserving efficacy in a multilingual context. To bridge this gap, this paper pioneers exploring and training powerful Multilingual Math Reasoning (xMR) LLMs. Firstly, by utilizing translation, we construct the first multilingual math reasoning instruction dataset, MGSM8KInstruct, encompassing ten distinct languages, thus addressing the issue of training data scarcity in xMR tasks. Based on the collected dataset, we propose different training strategies to build powerful xMR LLMs, named MathOctopus, notably outperform conventional open-source LLMs and exhibit superiority over ChatGPT in few-shot scenarios. Notably, MathOctopus-13B reaches 47.6% accuracy which exceeds ChatGPT 46.3% on MGSM testset. Beyond remarkable results, we unearth several pivotal observations and insights from extensive experiments: (1) When extending the rejection sampling strategy to the multilingual context, it proves effective for model performances, albeit limited. (2) Employing parallel corpora for math Supervised Fine-Tuning (SFT) across multiple languages not only significantly enhances model performance multilingually but also elevates their monolingual performance. This indicates that crafting multilingual corpora can be regarded as a vital strategy for enhancing model performance in a specific language, especially in mathematical reasoning tasks. For instance, MathOctopus-7B improves its counterparts that trained on English from 42.2% to 50.8% on GSM8K testset.Comment: Work in Progres

    Quantum PT-Phase Diagram in a Non-Hermitian Photonic Structure

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    Photonic structures have an inherent advantage to realize PT-phase transition through modulating the refractive index or gain-loss. However, quantum PT properties of these photonic systems have not been comprehensively studied yet. Here, in a bi-photonic structure with loss and gain simultaneously existing, we analytically obtained the quantum PT-phase diagram under the steady state condition. To characterize the PT-symmetry or -broken phase, we define an Hermitian exchange operator expressing the exchange between quadrature variables of two modes. If inputting several-photon Fock states into a PT-broken bi-waveguide splitting system, most photons will concentrate in the dominant waveguide with some state distributions. Quantum PT-phase diagram paves the way to the quantum state engineering, quantum interferences, and logic operations in non-Hermitian photonic systems.Comment: 6 pages, 3 figure

    Orca: A Few-shot Benchmark for Chinese Conversational Machine Reading Comprehension

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    The conversational machine reading comprehension (CMRC) task aims to answer questions in conversations, which has been a hot research topic in recent years because of its wide applications. However, existing CMRC benchmarks in which each conversation is assigned a static passage are inconsistent with real scenarios. Thus, model's comprehension ability towards real scenarios are hard to evaluate reasonably. To this end, we propose the first Chinese CMRC benchmark Orca and further provide zero-shot/few-shot settings to evaluate model's generalization ability towards diverse domains. We collect 831 hot-topic driven conversations with 4,742 turns in total. Each turn of a conversation is assigned with a response-related passage, aiming to evaluate model's comprehension ability more reasonably. The topics of conversations are collected from social media platform and cover 33 domains, trying to be consistent with real scenarios. Importantly, answers in Orca are all well-annotated natural responses rather than the specific spans or short phrase in previous datasets. Besides, we implement three strong baselines to tackle the challenge in Orca. The results indicate the great challenge of our CMRC benchmark. Our datatset and checkpoints are available at https://github.com/nuochenpku/Orca.Comment: 14 page

    DNetDB: The human disease network database based on dysfunctional regulation mechanism

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    Additional analysis and concepts explanation. This file contains 1) comparison of DNetDB and the results of differential expression analysis (DEA-) based method ; 2) comparison of DNetDB and traditional disease classification; 3) negative disease relationships and 4) DCp and DCe. (DOCX 6926 kb

    Frailty Screening and Detection of Geriatric Syndromes in Acute Inpatient Care: Impact on Hospital Length of Stay and 30-Day Readmissions

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    Background Frailty is prevalent in acute care and is associated with negative outcomes. While a comprehensive geriatric assessment to identify geriatric syndromes is recommended after identifying frailty, more evidence is needed to support this approach in the inpatient setting. This study examined the association between frailty and geriatric syndromes and their impact on outcomes in acutely admitted older adults. Methods A total of 733 individuals aged ≥65 years admitted to the General Surgery Service of a tertiary hospital were assessed for frailty using the Clinical Frailty Scale (CFS) and for geriatric syndromes using routine nursing admission assessments, including cognitive impairment, falls, incontinence, malnutrition, and poor oral health. Multinomial logistic regression and Cox regression were used to evaluate the associations between frailty and geriatric syndromes and their concomitant impact on hospital length of stay (LOS) and 30-day readmissions. Results Greater frailty severity was associated with an increased likelihood of geriatric syndromes. Individuals categorized as CFS 4–6 and CFS 7–8 with concomitant geriatric syndromes had 29% and 35% increased risks of a longer LOS, respectively. CFS 4–6 was significantly associated with functional decline (relative risk ratio =1.46; 95% confidence interval [CI], 1.03–2.07) and 30-day readmission (hazare ratio=1.78; 95% CI, 1.04–3.04), whereas these associations were not significant for CFS 7–8. Conclusions Geriatric syndromes in frail individuals can be identified from routine nursing assessments and represent a potential approach for targeted interventions following frailty identification. Tailored interventions may be necessary to achieve optimal outcomes at different stages of frailty. Further research is required to evaluate interventions for older adults with frailty in a wider hospital context

    Broad activation of the Parkin pathway induces synaptic mitochondrial deficits in early tauopathy

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    Mitochondrial defects are a hallmark of early pathophysiology in Alzheimer’s disease, with pathologically phosphorylated tau reported to induce mitochondrial toxicity. Mitophagy constitutes a key pathway in mitochondrial quality control by which damaged mitochondria are targeted for autophagy. However, few details are known regarding the intersection of mitophagy and pathologies in tauopathy. Here, by applying biochemical and cell biological approaches including time-lapse confocal imaging in live tauopathy neurons, combined with gene rescue experiments via stereotactic injections of adeno-associated virus particles into tauopathy mouse brains, electrophysiological recordings and behavioural tests, we demonstrate for the first time that mitochondrial distribution deficits at presynaptic terminals are an early pathological feature in tauopathy brains. Furthermore, Parkin-mediated mitophagy is extensively activated in tauopathy neurons, which accelerates mitochondrial Rho GTPase 1 (Miro1) turnover and consequently halts Miro1-mediated mitochondrial anterograde movement towards synaptic terminals. As a result, mitochondrial supply at tauopathy synapses is disrupted, impairing synaptic function. Strikingly, increasing Miro1 levels restores the synaptic mitochondrial population by enhancing mitochondrial anterograde movement and thus reverses tauopathy-associated synaptic failure. In tauopathy mouse brains, overexpression of Miro1 markedly elevates synaptic distribution of mitochondria and protects against synaptic damage and neurodegeneration, thereby counteracting impairments in learning and memory as well as synaptic plasticity. Taken together, our study reveals that activation of the Parkin pathway triggers an unexpected effect—depletion of mitochondria from synaptic terminals, a characteristic feature of early tauopathy. We further provide new mechanistic insights into how parkin activation-enhanced Miro1 degradation and impaired mitochondrial anterograde transport drive tauopathy-linked synaptic pathogenesis and establish a foundation for future investigations into new therapeutic strategies to prevent synaptic deterioration in Alzheimer’s disease and other tauopathies

    比利时

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    peer reviewedUltra-performance convergence chromatography is an environmentally-friendly analytical method that uses dramatically reduced amounts of organic solvents. In addition, a robust and highly sensitive chiral separation method was developed for the novel chiral acaricide cyflumetofen by using ultra-performance convergence chromatography coupled with tandem mass spectrometry, which shows that stereoisomer recoveries determined for various apple parts ranged from 78.3% to 119.9%, with the relative standard deviations being lower than 14.0%. The half-lives of (-)-cyflumetofen and (+)-cyflumetofen obtained under 5-fold applied dosage equal to 22.13 and 22.23 days, respectively. For 1.5-fold applied dosage, the respective values were determined as 22.42 and 23.64 days, i.e., the degradation of (-)-cyflumetofen was insignificantly favored over that of its enantiomer. Importantly, cyflumetofen was unevenly distributed in apples, with its relative contents in apple peel, peduncle, and pomace equal to 50%, 22%, and 16%, respectively. The proposed method can be used to efficiently separate and quantify chiral pesticide with advantages of a shorter analysis time, greater sensitivity, and better environmental compatibility. Additionally, the consumption of apples with residue of cyflumetofen did not pose a health risk to the population if the cyflumetofen applied under satisfactory agricultural practices after the long-term dietary risk assessment
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