2,298 research outputs found

    A Bi-Step Grounding Paradigm for Large Language Models in Recommendation Systems

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    As the focus on Large Language Models (LLMs) in the field of recommendation intensifies, the optimization of LLMs for recommendation purposes (referred to as LLM4Rec) assumes a crucial role in augmenting their effectiveness in providing recommendations. However, existing approaches for LLM4Rec often assess performance using restricted sets of candidates, which may not accurately reflect the models' overall ranking capabilities. In this paper, our objective is to investigate the comprehensive ranking capacity of LLMs and propose a two-step grounding framework known as BIGRec (Bi-step Grounding Paradigm for Recommendation). It initially grounds LLMs to the recommendation space by fine-tuning them to generate meaningful tokens for items and subsequently identifies appropriate actual items that correspond to the generated tokens. By conducting extensive experiments on two datasets, we substantiate the superior performance, capacity for handling few-shot scenarios, and versatility across multiple domains exhibited by BIGRec. Furthermore, we observe that the marginal benefits derived from increasing the quantity of training samples are modest for BIGRec, implying that LLMs possess the limited capability to assimilate statistical information, such as popularity and collaborative filtering, due to their robust semantic priors. These findings also underline the efficacy of integrating diverse statistical information into the LLM4Rec framework, thereby pointing towards a potential avenue for future research. Our code and data are available at https://github.com/SAI990323/Grounding4Rec.Comment: 17 page

    Direct fabrication of unsupported inclined aluminum pillars based on uniform micro droplets deposition

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    In order to investigate forming directly complex parts without support materials or structures by uniform micro droplets deposition technique, the present work focus on fabricating the unsupported inclined aluminum pillars through offset deposition. An experimental system is developed to produce and deposit uniform molten aluminum droplets. A model is introduced to describe the inclined angle of the droplet deposition at different offset ratios. A one dimensional heat transfer model is proposed to help select the initial temperature parameters of the impinging droplet and the previous solidified droplet to ensure that the fusion occurs. No melting, partial melting and excessive melting region at different offset ratios are determined. The correspondence between offset ratio and inclined angle is considered to be a simple cosine function, and the hypothesis is verified by experiments. The influence of deposition error on an inclined angle of pillars is studied. Internal microstructure of droplet fusion is observed in order to ensure good metallurgical bonding. All of these studies show the feasibility of fabricating directly unsupported inclined aluminum pillars in the limited angle range by using uniform micro droplets

    Low-Cost Electrical Beam-Scanning Leaky-Wave Antenna Based on Bent Corrugated Substrate Integrated Waveguide

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    This letter presents a novel low-cost leaky-wave antenna (LWA) with the fixed-frequency beam-scanning capability. An improved half-mode corrugated substrate integrated waveguide structure is proposed as the guiding wave structure to reduce the transverse size of the antenna. A novel electronic phase-shifting structure, composed of fan-shaped open stubs with different sizes and PIN diodes, is proposed for beam scanning. This LWA uses interdigital slots as radiating elements, and the phase-shifting structure is placed between the adjacent radiating elements. By changing the switching states of these PIN diodes, the phase difference between the adjacent radiating elements can be controlled. To verify the concept, one prototype of the 2 × 6 array antenna at C -band is designed, simulated, fabricated, and measured. The antenna demonstrates a beam-scanning range of 25° (34°–59°) at fixed frequency, a peak gain of 12.4 dBi with the gain variation less than 2.3 dB. The antenna has low cost and can be easily fabricated using standard printed circuit board process

    Plant Regeneration from Cassava Protoplasts

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    Cassava is an important crop for food, feed, and industrial raw materials. Given that traditional conventional breeding is restricted by various factors, biotechnology breeding has become an important breeding method. Tissue culture regeneration is the basis of biotechnology breeding. This chapter reviews the establishment and development of cassava tissue culture and regeneration systems and the technical processes of tissue culture and regeneration starting from the induction of explants of tissue-cultured cassava plantlets to embryogenic calli, isolation to protoplasts, culture to embryogenic calli followed by differentiation into embryos, and then sprouting, stemming, and rooting into complete plants. This chapter focuses on the technical processes from protoplast to complete plant and summarizes the important influencing factors of protoplast regeneration, which is the key and difficult point in the entire regeneration process of cassava protoplasts. This chapter aims to provide technical guidance for cassava protoplast regeneration, offer useful inspiration and reference for cassava tissue culture, and lay a foundation for the genetic improvement of cassava

    Assembling a Natural Small Molecule into a Supramolecular Network with High Structural Order and Dynamic Functions

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    Programming the hierarchical self-assembly of small molecules has been a fundamental topic of great significance in biological systems and artificial supramolecular systems. Precise and highly programmed self-assembly can produce supramolecular architectures with distinct structural features. However, it still remains a challenge how to precisely control the self-assembly pathway in a desirable way by introducing abundant structural information into a limited molecular backbone. Here we disclose a strategy that directs the hierarchical self-assembly of sodium thioctate, a small molecule of biological origin, into a highly ordered supramolecular layered network. By combining the unique dynamic covalent ring-opening-polymerization of sodium thioctate and an evaporation-induced interfacial confinement effect, we precisely direct the dynamic supramolecular self-assembly of this simple small molecule in a scheduled hierarchical pathway, resulting in a layered structure with long-range order at both macroscopic and molecular scales, which is revealed by small-angle and wide-angle X-ray scattering technologies. The resulting supramolecular layers are found to be able to bind water molecules as structural water, which works as an interlayer lubricant to modulate the material properties, such as mechanical performance, self-healing capability, and actuating function. Analogous to many reversibly self-assembled biological systems, the highly dynamic polymeric network can be degraded into monomers and reformed by a water-mediated route, exhibiting full recyclability in a facile, mild, and environmentally friendly way. This approach for assembling commercial small molecules into structurally complex materials paves the way for low-cost functional supramolecular materials based on synthetically simple procedures

    Crosstalk between the CBM complex/NF-ÎşB and MAPK/P27 signaling pathways of regulatory T cells contributes to the tumor microenvironment

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    Regulatory T cells (Tregs), which execute their immunosuppressive functions by multiple mechanisms, have been verified to contribute to the tumor microenvironment (TME). Numerous studies have shown that the activation of the CBM complex/NF-κB signaling pathway results in the expression of hypoxia-inducible factor-1 (HIF-1α) and interleukin-6 (IL-6), which initiate the TME formation. HIF-1α and IL-6 promote regulatory T cells (Tregs) proliferation and migration through the MAPK/CDK4/6/Rb and STAT3/SIAH2/P27 signaling pathways, respectively. IL-6 also promotes the production of HIF-1α and enhances the self-regulation of Tregs in the process of tumor microenvironment (TME) formation. In this review, we discuss how the crosstalk between the CARMA1–BCL10–MALT1 signalosome complex (CBM complex)/NF-κB and MAPK/P27 signaling pathways contributes to the formation of the TME, which may provide evidence for potential therapeutic targets in the treatment of solid tumors
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