87 research outputs found
Distribution of Onryza maga (Leech, 1890) (Lepidoptera: Hesperiidae) with description of female genitalia and taxonomic notes
For more than twenty years, Hainan, Vietnam, Myanmar, Thailand, Malaysia, Singapore and Indonesia have been erroneously reported in Chinese literature as belonging to the distribution range of Onryza maga (Leech 1890). Based upon a careful survey of specimens and relevant literature, these regions are omitted from the known range of this species. Onryza maga maga is found from northeast Guizhou, south Henan and Qinling-Daba Mountains in Shaanxi of China, its occurrence in Hunan is confirmed. The adults are redescribed and the variability of wing patterns is discussed. Female genitalia are illustrated and described for the first time. Some biological information and an updated distribution map of the species are provided
Highly Efficient and Reversible Iodine Capture in Hexaphenylbenzene-Based Conjugated Microporous Polymers
The effective and safe capture and
storage of radioactive iodine (<sup>129</sup>I or <sup>131</sup>I)
is of significant importance during nuclear waste storage and nuclear
energy generation. Here we present detailed evidence of highly efficient
and reversible iodine capture in hexaphenylÂbenzene-based conjugated
microporous polymers (HCMPs), synthesized via Buchwald–Hartwig
(BH) cross-coupling of a hexakisÂ(4-bromoÂphenyl)Âbenzene (HBB)
core and aryl diamine linkers. The HCMPs present moderate surface
areas up to 430 m<sup>2</sup> g<sup>–1</sup>, with narrow pore
size distribution and uniform ultramicropore sizes of less than 1
nm. Porous properties are controlled by the strut lengths and rigidities
of linkers, while porosity and uptake properties can be tuned by changing
the oxidation state of the HCMPs. The presence of a high number of
amine functional groups combined with microporosity provides the HCMPs
with extremely high iodine affinity with uptake capacities up to 336
wt %, which is to the best of our knowledge the highest reported to
date. Two ways to release the adsorbed iodine were explored: either
slow release into ethanol or quick release upon heating (with a high
degree of control). Spectral studies indicate that the combination
of microporosity, amine functionality, and abundant π-electrons
ensured well-defined host–guest interactions and controlled
uptake of iodine. In addition, the HCMPs could be recycled while maintaining
90% iodine uptake capacity (up to 295%). We envisage wider application
of these materials in the facile uptake and removal of unwanted oxidants
from the environment
Hypersonic Vehicles Profile-Following Based on LQR Design Using Time-Varying Weighting Matrices
In the process of applying linear quadratic regulator (LQR) to solve aerial vehicle reentry reference trajectory guidance, to obtain better profile-following performance, the parameters of the aerial vehicle system can be used to calculate weighting matrices according to the Bryson principle. However, the traditional method is not applicable to various disturbances in hypersonic vehicles (HSV) which have particular dynamic characteristics. By calculating the weighting matrices constructed based on Bryson principle using time-varying parameters, a novel time-varying LQR design method is proposed to deal with the various disturbances in HSV reentry profile-following. Different from the previous approaches, the current states of the flight system are employed to calculate the parameters in weighting matrices. Simulation results are given to demonstrate that using the proposed approach in this chapter, performance of HSV profile-following can be improved significantly, and stronger robustness against different disturbances can be obtained
CohortGPT: An Enhanced GPT for Participant Recruitment in Clinical Study
Participant recruitment based on unstructured medical texts such as clinical
notes and radiology reports has been a challenging yet important task for the
cohort establishment in clinical research. Recently, Large Language Models
(LLMs) such as ChatGPT have achieved tremendous success in various downstream
tasks thanks to their promising performance in language understanding,
inference, and generation. It is then natural to test their feasibility in
solving the cohort recruitment task, which involves the classification of a
given paragraph of medical text into disease label(s). However, when applied to
knowledge-intensive problem settings such as medical text classification, where
the LLMs are expected to understand the decision made by human experts and
accurately identify the implied disease labels, the LLMs show a mediocre
performance. A possible explanation is that, by only using the medical text,
the LLMs neglect to use the rich context of additional information that
languages afford. To this end, we propose to use a knowledge graph as auxiliary
information to guide the LLMs in making predictions. Moreover, to further boost
the LLMs adapt to the problem setting, we apply a chain-of-thought (CoT) sample
selection strategy enhanced by reinforcement learning, which selects a set of
CoT samples given each individual medical report. Experimental results and
various ablation studies show that our few-shot learning method achieves
satisfactory performance compared with fine-tuning strategies and gains superb
advantages when the available data is limited. The code and sample dataset of
the proposed CohortGPT model is available at:
https://anonymous.4open.science/r/CohortGPT-4872/Comment: 16 pages, 10 figure
Optimum Pipeline for Visual Terrain Classification Using Improved Bag of Visual Words and Fusion Methods
We propose an optimum pipeline and develop the hybrid representation to produce an effective and efficient visual terrain classification system. The bag of visual words (BOVW) framework has emerged as a promising approach and effective paradigm for visual terrain classification. The method includes four main steps: (1) feature extraction, (2) codebook generation, (3) feature coding, and (4) pooling and normalization. Recent researches have primarily focused on feature extraction in the development of new handcrafted descriptors that are specific to the visual terrain. However, the effects of other steps on visual terrain classification are still unknown. At the same time, fusion methods are often used to boost classification performance by exploring the complementarity of diverse features. We provide a comprehensive study of all steps in the BOVW framework and different fusion methods for visual terrain classification. Then, multiple approaches in each step and their effects are explored on the visual terrain dataset. Finally, the feature preprocessing technique, improved BOVW framework, and fusion method are used to construct an optimum pipeline for visual terrain classification. The hybrid representation developed by the optimum pipeline performs effectively and rapidly for visual terrain classification in the terrain dataset, outperforming those current methods. Furthermore, it is robust to diverse noises and illumination alterations
A novel unambiguous strategy of molecular feature extraction in machine learning assisted predictive models for environmental properties
Environmental properties of compounds provide significant information in treating organic pollutants, which drives the chemical process and environmental science toward eco-friendly technology. Traditional group contribution methods play an important role in property estimations, whereas various disadvantages emerge in their applications, such as scattered predicted values for certain groups of compounds. In order to address such issues, an extraction strategy for molecular features is proposed in this research, which is characterized by interpretability and discriminating power with regard to isomers. Based on the Henry's law constant data of organic compounds in water, we developed a hybrid predictive model that integrates the proposed strategy in conjunction with a neural network framework. The structure of the predictive model is optimized using cross-validation and grid search to improve its robustness. Moreover, the predictive model is improved by introducing the plane of best fit descriptor as input and adopting k-means clustering in sampling. In contrast with reported models in the literature, the developed predictive model demonstrates improved generality, higher accuracy, and fewer molecular features used in its development
Search for light dark matter from atmosphere in PandaX-4T
We report a search for light dark matter produced through the cascading decay
of mesons, which are created as a result of inelastic collisions between
cosmic rays and Earth's atmosphere. We introduce a new and general framework,
publicly accessible, designed to address boosted dark matter specifically, with
which a full and dedicated simulation including both elastic and quasi-elastic
processes of Earth attenuation effect on the dark matter particles arriving at
the detector is performed. In the PandaX-4T commissioning data of 0.63
tonneyear exposure, no significant excess over background is observed.
The first constraints on the interaction between light dark matter generated in
the atmosphere and nucleus through a light scalar mediator are obtained. The
lowest excluded cross-section is set at for
dark matter mass of MeV and mediator mass of 300 MeV. The
lowest upper limit of to dark matter decay branching ratio is
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