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Exploration of chromene-based BioAIEgens

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National Science Review 2024年第3期11卷 47-48页

作者： Fritz E.kühn Department of Chemistry&Catalysis Research Center School of Natural Sciences Technical University of Munich

photoemission efficiency is usually higher in solution than in solid *** compounds however, display a reverse behavior. Such a behavior is called aggregation-induced emission(AIE).

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Direct-to-indirect mapping for optimal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen Ryan p.Russell Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Optimal,many-revolution spacecraft trajectories are challenging to solve.A connection is made for a class of models between optimal direct and indirect *** transfers that minimize thrust-acceleration-squared,primer vector theory maps direct,many-impulsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** mapping algorithm is independent of how the direct solution is obtained and requires only a solver for a boundary value problem and its partial derivatives.A Lambert solver is used for the two-body problem in this *** mapping is simple because the impulsive maneuvers and co-states share the same linear space around an optimal *** numerical results,the direct coast-impulse solutions are demonstrated to converge to the indirect continuous solutions as the number of impulses and segments *** two-body design space is explored with a set of three many-revolution,many-segment examples changing semimajor axis,eccentricity,and *** first two examples involve a small change to either semimajor axis or eccentricity,and the third example is a transfer to geosynchronous *** a single processor,the optimization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examples with up to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotopy to a higher-fidelity minimization problem with practical constraints.

关键词： direct optimization indirect optimization impulsive maneuvers Lambert's problem two-body dynamics primer vectortheory

palladium-catalyzed S_(N)2 glycosylation of phenols

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Science China Chemistry 2024年第4期67卷 1037-1038页

作者： Yu Zhu p.Andrew Evans Department of Chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya School of pharmaceutical Sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties palladium catalyzed

EVOLUTION AND INTERACTION OFδ-WAVES IN THE ZERO-pRESSURE GAS DYNAMICS SYSTEM

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Acta Mathematica Scientia 2024年第5期44卷 1801-1836页

作者： Abhishek DAS k.T.JOSEpH Centre for Data Science Institute of Technical Education and Research(ITER)Siksha‘O’Anusandhan(Deemed to be University)BhubaneswarOdisha751030India Centre for Applicable Mathematics Tata Institute of Fundamental ResearchSharada NagarBangalore560065KarnatakaIndia

Evolution and interaction of plane waves of the multidimensional zero-pressure gas dynamics system leads to the study of the corresponding one dimensional *** this paper,we study the initial value problem for one dimensional zero-pressure gas dynamics *** the first equation is the Burgers equation and the second one is the continuity *** consider the solution with initial data in the space of bounded Borel *** we prove a general existence result in the algebra of generalized functions of *** we study in detail special solutions withδ-measures as initial *** study interaction of waves originating from initial data concentrated on two point sources and interaction with classical shock/rarefaction *** gives an understanding of plane-wave interactions in the multidimensional *** use the vanishing viscosity method in our analysis as this gives the physical solution.

关键词： zero-pressure gas dynamics delta-waves interaction of waves

Classification of Conversational Sentences Using an Ensemble pre-Trained Language Model with the Fine-Tuned parameter

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Computers, Materials & Continua 2024年第2期78卷 1669-1686页

作者： R.Sujatha k.Nimala Department of Networking and Communications SRM Institute of Science and TechnologyKattankulathurChengalpattuTamilnadu603203India

Sentence classification is the process of categorizing a sentence based on the context of the *** categorization requires more semantic highlights than other tasks,such as dependence parsing,which requires more syntactic *** existing strategies focus on the general semantics of a conversation without involving the context of the sentence,recognizing the progress and comparing *** ensemble pre-trained language model was taken up here to classify the conversation sentences from the conversation *** conversational sentences are classified into four categories:information,question,directive,and *** classification label sequences are for analyzing the conversation progress and predicting the pecking order of the *** of Bidirectional Encoder for Representation of Transformer(BERT),Robustly Optimized BERT pretraining Approach(RoBERTa),Generative pre-Trained Transformer(GpT),DistilBERT and Generalized Autoregressive pretraining for Language Understanding(XLNet)models are trained on conversation corpus with *** tuning approach is carried out for better performance on sentence *** Ensemble of pre-trained Language Models with a Hyperparameter Tuning(EpLM-HT)system is trained on an annotated conversation *** proposed approach outperformed compared to the base BERT,GpT,DistilBERT and XLNet transformer *** proposed ensemble model with the fine-tuned parameters achieved an F1_score of 0.88.

关键词： Bidirectional encoder for representation of transformer conversation ensemble model fine-tuning generalized autoregressive pretraining for language understanding generative pre-trained transformer hyperparameter tuning natural language processing robustly optimized BERT pretraining approach sentence classification transformer models

Controlled deployment of a long tether to operate as a partial space elevator

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Astrodynamics 2024年第2期8卷 311-321页

作者： Jinbang Huang Arun k.Misra Department of Mechanical Engineering McGill UniversityMontrealQCH3A 0C3Canada

The deployment of a long tether to operate as a partial space elevator,starting from a nucleus in geostationary orbit,is *** deployment is an inherently unstable process because the center of orbit gradually decreases from the geostationary altitude when deployment *** is also observed that the elasticity of the tether has an important effect on deployment *** is shown that the application of a transverse force on the main spacecraft,determined by using linear state feedback and appropriate gains,can stabilize the *** LQR controller is *** of the dynamics of the system are carried out using this controller for various parametric values of tether elasticity,deployment rates,etc.,to evaluate the efficacy of the controller.

关键词： tether space elevator deployment stability control

Trusted Certified Auditor Using Cryptography for Secure Data Outsourcing and privacy preservation in Fog-Enabled VANETs

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Computers, Materials & Continua 2024年第5期79卷 3089-3110页

作者： Nagaraju pacharla k.Srinivasa Reddy School of Computer Science and Engineering VIT-AP UniversityAmaravatiAndhra Pradesh522237India

With the recent technological developments,massive vehicular ad hoc networks(VANETs)have been established,enabling numerous vehicles and their respective Road Side Unit(RSU)components to communicate with *** best way to enhance traffic flow for vehicles and traffic management departments is to share thedata they *** needs to be more protection for the VANET *** effective and safe methodof outsourcing is suggested,which reduces computation costs by achieving data security using a homomorphicmapping based on the conjugate operation of *** research proposes a VANET-based data outsourcingsystem to fix the *** keep data outsourcing secure,the suggested model takes cryptography models *** will keep the generated keys for the purpose of vehicle *** controlling and overseeingthe outsourced data while preserving privacy,the suggested approach considers the Trusted Certified Auditor(TCA).Using the secret key,TCA can identify the genuine identity of VANETs when harmful messages *** proposed model develops a TCA-based unique static vehicle labeling system using cryptography(TCA-USVLC)for secure data outsourcing and privacy preservation in *** proposed model calculatesthe trust of vehicles in 16 ms for an average of 180 vehicles and achieves 98.6%accuracy for data encryption toprovide *** proposedmodel achieved 98.5%accuracy in data outsourcing and 98.6%accuracy in privacypreservation in fog-enabled *** curve cryptography models can be applied in the future for betterencryption and decryption rates with lightweight cryptography operations.

关键词： Vehicular ad-hoc networks data outsourcing privacy preservation cryptography keys trusted certified auditors data security

Molecular pathology for cholangiocarcinoma:a review of actionable genetic targets and their relevance to adjuvant&neoadjuvant therapy,staging,follow-up,and determination of minimal residual disease

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Hepatobiliary Surgery and Nutrition 2024年第1期13卷 29-38页

作者： Emilie A.k.Warren Shishir k.Maithel Division of Surgical Oncology Winship Cancer InstituteEmory UniversityAtlantaGAUSA

Cholangiocarcinoma(CCA)represents a group of epithelial cell tumors classified based on their anatomic location along the biliary *** rare malignancy is often diagnosed at an advanced stage and deemed *** for those patients who are surgical candidates,recurrence rates are high and survival rates *** mainstay of therapy for advanced CCA remains cisplatin plus gemcitabine,with a median overall survival(mOS)under 12 months,although the TOpAZ-1 trial showed a survival benefit with the addition of programmed cell death ligand 1(pD-L1)*** recent years,molecular profiling has revealed a wealth of potentially targetable genetic alterations,including fibroblast growth factor receptor(FGFR)fusions,isocitrate dehydrogenase 1(IDH1)mutations,human epidermal growth factor receptor 2(HER2)amplification and overexpression,and microsatellite instability(MSI).These discoveries have prompted numerous clinical trials employing drugs against these specific genetic *** foundation laid by early clinical studies and the landscape of ongoing trials are both summarized *** the role of adjuvant therapy has yet to be defined in this disease,we emphasize the importance of employing targeted therapies in trials in the adjuvant and neoadjuvant spaces and discuss ways to overcome challenges due to low incidence of targetable *** medicine for this disease promises significant clinical benefit to patients,but further investigation is needed.

关键词： Cholangiocarcinoma(CCA) biliary tract cancer(BTC) targeted therapy molecular profiling

Surgical treatment of inflammatory bowel disease:From the gastroenterologist’s stand-point

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1235-1254页

作者： John k Triantafillidis Inflammatory Bowel Disease Unit “Metropolitan General”HospitalHolargos 15562AtticaGreece Hellenic Society of Gastrointestinal Oncology Haidari 12461AthensGreece

Treatment of ulcerative colitis(UC)and Crohn’s disease(CD)represents,in the majority of cases,a real challenge to the gastroenterologist’s abilities and skills as well as a clinical test concerning his/her levels of medical knowledge and *** the last two decades,our pharmaceutical arsenal was significantly strengthened,especially after the introduction of the so-called biological agents,drugs which to a large extent not only improved the results of conservative treatment but also changed the natural history of the ***,colectomy is still necessary for some patients with severe UC although smaller compared to the past,precisely because of the improvements achieved in the available conservative ***,surgeries to treat colon dysplasia and cancer are increasing to some *** the same time,satisfactory improvements in surgical techniques,the pre-and post-operative care of patients,as well as the selection of the appropriate time for performing the surgery have been *** patients with CD,the improvement of conservative treatment did not significantly change the need for surgical treatment since two-thirds of patients need to undergo surgery at some point in the course of their *** the other hand,the outcome of the operation has improved through good preoperative care as well as the wide application of more conservative surgical techniques aimed at keeping as much of the bowel in situ as *** article discusses the indications for surgical management of UC patients from the gastroenterologist’s point of view,the results of the emerging new techniques such as transanal surgery and robotics,as well as alternative operations to the classic ileo-anal-pouch *** author also discusses the basic principles of surgical management of patients with CD based on the results of the relevant *** self-evident is emphasized,that is,to achieve an excellent therapeutic result in patients with se

关键词： Inflammatory bowel disease Ulcerative colitis Crohn’s disease Surgery Treatment Ileo-anal-pouch anastomosis Indications Techniques