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emission colour tuning in kLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani k Gayathri e Vijayatha V Ramasubramanian S Thiyagarajan P Department of Science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of Sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

kLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped kYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped kGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped kYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： M Setodeh kheirabady M k Tavassoly M Rafeie e Ghasemian Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of electrical engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. More interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： k.D.James J.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

LiDAR-based estimation of bounding box coordinates using Gaussian process regression and particle swarm optimization

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Biomimetic Intelligence & Robotics 2024年第1期4卷 24-35页

作者： Vinodha k. e.S.Gopi Tushar Agnibhoj Department of electronics and Communication engineering National Institute of Technology TiruchirappalliTamil Nadu620015India

Camera-based object tracking systems in a given closed environment lack privacy and *** this study,light detection and ranging(LiDAR)was applied to track objects similar to the camera tracking in a closed environment,guaranteeing privacy and *** primary objective was to demonstrate the efficacy of the proposed technique through carefully designed experiments conducted using two *** Scenario I,the study illustrates the capability of the proposed technique to detect the locations of multiple objects positioned on a flat surface,achieved by analyzing LiDAR data collected from several locations within the closed *** II demonstrates the effectiveness of the proposed technique in detecting multiple objects using LiDAR data obtained from a single,fixed ***-time experiments are conducted with human subjects navigating predefined *** individuals move within an environment,while LiDAR,fixed at the center,dynamically tracks and identifies their locations at multiple *** demonstrate that a single,strategically positioned LiDAR can adeptly detect objects in motion around ***,this study provides a comparison of various regression techniques for predicting bounding box *** process regression(GPR),combined with particle swarm optimization(PSO)for prediction,achieves the lowest prediction mean square error of all the regression techniques examined at *** tuning of GPR using PSO significantly minimizes the regression *** of the experiment pave the way for its extension to various real-time applications such as crowd management in malls,surveillance systems,and various Internet of Things scenarios.

关键词： LiDAR Data acquisition Bounding box Gaussian process regression Particle swarm optimization(PSO)

Immunotherapy of gastric cancer:Present status and future perspectives

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World Journal of Gastroenterology 2024年第8期30卷 779-793页

作者： John k Triantafillidis Manousos M konstadoulakis Apostolos e Papalois Inflammatory Bowel Disease Unit “Metropolitan General”HospitalHolargos 15562AtticaGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece Second Department of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528AtticaGreece Unit of Surgical Research and Training Second Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528AtticaGreece

In this editorial,we comment on the article entitled“Advances and key focus areas in gastric cancer immunotherapy:A comprehensive scientometric and clinical trial review(1999-2023),”which was published in the recent issue of the World Journal of *** focused on the results of the authors’bibliometric analysis concerning gastric cancer immunotherapy,which they analyzed in depth by compiling the relevant publications of the last 20 *** that,we briefly describe the most recent data concerning the epidemiological parameters of gastric cancer(GC)in different countries,attempting to give an interpretation based on the etiological factors involved in the etiopathogenesis of the *** then briefly discuss the conservative treatment(chemotherapy)of the various forms of this malignant *** describe the treatment of resectable tumors,locally advanced neoplasms,and unresectable(advanced)*** attention is given to modern therapeutic approaches with emphasis on immunotherapy,which seems to be the future of GC treatment,especially in combination with *** is also a thorough analysis of the results of the study under review in terms of the number of scientific publications,the countries in which the studies were conducted,the authors,and the scientific centers of origin,as well as the clinical studies in ***,an attempt is made to draw some conclusions and to point out possible future directions.

关键词： Gastric cancer Chemotherapy Immunotherapy Immune checkpoint inhibitors Bibliometrics Scientometrics

Combination treatment of inflammatory bowel disease:Present status and future perspectives

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World Journal of Gastroenterology 2024年第15期30卷 2068-2080页

作者： John k Triantafillidis Constantinos G Zografos Manousos M konstadoulakis Apostolos e Papalois Inflammatory Bowel Disease Unit "Metropolitan General"HospitalHolargos 15562AtticaGreece Hellenic Society for Gastrointestinal Oncology 354 Iera OdosChaidari 12461AtticaGreece The 2^(nd)Department of Surgery University of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece Unit of Surgical Research and Training The 2^(nd)Department of SurgeryUniversity of AthensSchool of MedicineAretaieion HospitalAthens 11528Greece

The treatment of patients with inflammatory bowel disease(IBD),especially those with severe or refractory disease,represents an important challenge for the clinical *** seems to be no exaggeration to say that in these patients,not only the scientific background of the gastroenterologist is tested,but also the abundance of“gifts”that he should possess(insight,intuition,determ-ination,ability to take initiative,etc.)for the successful outcome of the *** daily clinical practice,depending on the severity of the attack,IBD is treated with one or a combination of two or more pharmaceutical *** combin-ations include not only the first-line drugs(e.g.,mesalazine,corticosteroids,antibiotics,etc)but also second-and third-line drugs(immunosuppressants and biologic agents).It is a fact that despite the significant therapeutic advances there is still a significant percentage of patients who do not satisfactorily respond to the treatment ***,a part of these patients are going to *** recent years,several small-size clinical studies,reviews,and case reports have been published combining not only biological agents with other drugs(e.g.,immunosuppressants or corticosteroids)but also the combination of two biologi-cal agents simultaneously,especially in severe *** our opinion,it is at least a strange(and largely unexplained)fact that we often use combinations of drugs in a given patient although studies comparing the simultaneous administration of two or more drugs with monotherapy are very *** mentioned above,there is a timid tendency in the literature to combine two biological agents in severe cases unresponsive to the applied treatment or patients with severe extraintestinal *** appropriate dosage,the duration of the administration,the suitable timing for checking the clinical and laboratory outcome,as well as the treatment side-effects,should be the subject of intense clinical research *** this

关键词： Biologics for immune-mediated conditions Dual-targeted treatment Combination treatment Inflammatory bowel disease Crohn’s

extractable and kerogen-bound hopanoids from typical eocene oil shales in China

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energy Geoscience 2024年第2期5卷 171-179页

作者： Changbo Zhai Zhirong Zhang John k.Volkman Hong Lu Yan'e Chen SINOPeC key Laboratory of Petroleum Accumulation Mechanisms Wuxi Institute of Petroleum GeologySINOPEC2060 Lihu RoadWuxiJiangsu213126China SINOPeC Petroleum exploration and Production Research Institute 31 Xueyuan RoadBeijing100083China State key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of ScienceGuangzhou510640GuangdongChina

This study conducted a comparative analysis of extractable hopanoid hydrocarbons and those released via stepwise pyrolysis of typical eocene immature oil shales in China,namely the Huadian,Maoming,and Fushun *** the Huadian and Maoming shales exhibit immature indicators in extractable and kerogen-bound hopanoids(notably,high abundance of C_(29)to C_(32)17β,21β-hopanes and unsaturated hopenes).In contrast,the Fushun oil shale's hopanoids from extracts and pyrolyzates suggest a higher maturity *** absence of neohopenes in the pyrolyzates of the shales underpins that the kerogenbound hopanoid skeletons resist ***,the Huadian oil shale's asymmetric distribution of C_(29)and C_(30)hopenes and neohopenes hints at the presence of an additional *** unsaturated hopenes,such as hop-20(21)-enes,identified in pyrolyzates of the three kerogens at various pyrolysis temperatures,reveal the occurrence of double bonds in kerogen-bound hopanoid skeletons without methyl *** absence of hop-20-(21)-ene in extracts suggests that it might act as an intermediate of these novel hopenes during the epimerization of hopanoid skeletons within *** extractable and pyrolytic hopanoids'stereochemical alignment indicates that epimerization may occur in both ring systems and alkyl side chains of kerogen-bound hopanoid *** stepwise pyrolysis proves to be a quick screening method for geological hopanoids without causing any significant alteration to the original skeletons even when cracking multiple covalent bonds is necessary.

关键词： Hopanoid Hopane Hopene Neohopene Stepwise pyrolysis kerogen eocene oil shale

early-onset gastrointestinal cancer:An epidemiological reality with great significance and implications

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 583-597页

作者： John k Triantafillidis konstantinos Georgiou Manousos M konstadoulakis Apostolos e Papalois Department of IBD and GI endoscopy Metropolitan General HospitalHolargos 15562AthensGreece.Hellenic Society for Gastrointestinal Oncology354 Iera OdosChaidari 12461AtticaGreece 2nd Department of Surgery University of Athens School of MedicineAretaieion HospitalAthens 11528Greece

During the last few years,epidemiological data from many countries suggest that the incidence and prevalence of many cancers of the digestive system are shifting from the older to the younger ages,the so-called“early-onset cancer”.This is particularly evident in colorectal cancer and secondarily in other malignant digestive neoplasms,mainly stomach and in a lesser degree pancreas,and biliary *** should be emphasized that data concerning digestive neoplasms,except for those referring to the colon and stomach,could be characterized as rather *** exact magnitude of the shift in younger ages is expected to become clearer shortly,as long as relevant epidemiological data from many parts of the world would be *** most important question concerns the etiology of this phenomenon,since its magnitude cannot be explained solely by the better diagnostic methodology and the preventive programs applied in many *** existing data support the assumption that a number of environ-mental factors may play a primary role in influencing carcinogenesis,sometimes from *** that have appeared in the last decades related mainly to eating habits,consistency of gut microbiome and an increase of obese people interacting with genetic factors,ultimately favor the process of *** these factors however,are not entirely sufficient to explain the age-related changes in the frequency of digestive *** of the individual effect of each of the already known factors or factors likely to be involved in the etiology of this phenomenon and studies using state-of-the-art technologies to accurately determine the degree of the population exposure to these factors are *** this article,we attempt to describe the epidemiological data supporting the age-shifting of digestive malignancies and their possible ***,we propose some measures regarding the attitude of the scientific community to this alarming phenomenon.

关键词： Gastrointestinal cancer endoscopy epidemiology early-onset environment

Instance Segmentation of Characters Recognized in Palmyrene Aramaic Inscriptions

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Computer Modeling in engineering & Sciences 2024年第9期140卷 2869-2889页

作者： Adéla Hamplová Alexey Lyavdansky TomášNovák Ondrej Svojše David Franc Arnošt Veselý Czech University of Life Sciences in Prague(CULS) Faculty of Economics and ManagementDepartment of Information EngineeringPrague16500Czech Republic National Research University Higher School of economics(HSe) Faculty of HumanitiesInstitute for Oriental and Classical StudiesMoscow101000The Russian Federation

This study presents a single-class and multi-class instance segmentation approach applied to ancient Palmyrene inscriptions,employing two state-of-the-art deep learning algorithms,namely YOLOv8 and Roboflow *** goal is to contribute to the preservation and understanding of historical texts,showcasing the potential of modern deep learning methods in archaeological *** research culminates in several key findings and scientific *** comprehensively compare the performance of YOLOv8 and Roboflow 3.0 in the context of Palmyrene character segmentation—this comparative analysis mainly focuses on the strengths and weaknesses of each algorithm in this *** also created and annotated an extensive dataset of Palmyrene inscriptions,a crucial resource for further research in the *** dataset serves for training and evaluating the segmentation *** employ comparative evaluation metrics to quantitatively assess the segmentation results,ensuring the reliability and reproducibility of our findings and we present custom visualization tools for predicted segmentation *** study advances the state of the art in semi-automatic reading of Palmyrene inscriptions and establishes a benchmark for future *** availability of the Palmyrene dataset and the insights into algorithm performance contribute to the broader understanding of historical text analysis.

关键词： Optical character recognition instance segmentation Palmyrene ancient languages computer vision