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Pancreatic cancer stem cell markers and exosomes-the incentive push

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World Journal of Gastroenterology 2016年第26期22卷 5971-6007页

作者： sarah Heiler Zhe Wang Margot Zoller Tumor Cell Biology University Hospital of SurgeryD 69120 HeidelbergGermany

Pancreatic cancer(Pa Ca) has the highest death rate and incidence is increasing. Poor prognosis is due to late diagnosis and early metastatic spread, which is ascribed to a minor population of so called cancer stem cells(CSC) within the mass of the primary tumor. CSC are defined by biological features, which they share with adult stem cells like longevity, rare cell division, the capacity for self renewal, differentiation, drug resistance and the requirement for a niche. CSC can also be identified by sets of markers, which for pancreatic CSC(Pa-CSC) include CD44v6, c-Met, Tspan8, alpha6beta4, CXCr4, CD133, Ep CAM and claudin7. The functional relevance of CSC markers is still disputed. We hypothesize that Pa-CSC markers play a decisive role in tumor progression. This is fost.red by the location in glycolipid-enriched membrane domains, which function as signaling platform and support connectivity of the individual Pa-CSC markers. Outsidein signaling supports apoptosis resistance, stem cell gene expression and tumor suppressor gene repression as well as mi rNA transcription and silencing. Pa-CSC markers also contribute to motility and invasiveness. By ligand binding host cells are triggered towards creating a milieu supporting Pa-CSC maintenance. Furthermore, CSC markers contribute to the generation, loading and delivery of exosomes, whereby CSC gain the capacity for a cell-cell contact independent crosstalk with the host and neighboring non-CSC. This allows PaCSC exosomes(TEX) to reprogram neighboring nonCSC towards epithelial mesenchymal transition and to stimulate host cells towards preparing a niche for metastasizing tumor cells. Finally, TEX communicate with the matrix to support tumor cell motility, invasion and homing. We will discuss the possibility that CSC markers are the initial trigger for these processes and what is the special contribution of CSC-TEX.

关键词： Pancreatic cancer Cancer stem cells Stem cell markers Exosomes Crosstalk

The Utilization of Low Frequency raman Spectra of Gases for the Study of Molecules with Large Amplitude Vibration

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光散射学报 2009年第3期21卷 201-215页

作者： James r.Durig sarah Xiao-hua Zhou Joshua Klaassen Arindam Ganguly University of Missouri-Kansas City

The utilization of the raman spectra of the low frequency bending mode for three quasi-linear molecules: disiloxane,(SiH3)2O;methylisocyanate,CH3NCO;and dimethylisocyanate,(CH3)2SiHNCO for observing the low frequency anharmonic bending vibration is demonstrated which is superior to the corresponding far infrared *** the observed frequencies from the raman spectra the potential function governing the heavy atom motion to linearity has been obtained from which the barrier has been *** experimental values are compared to the ab initio predicted *** low frequency raman spectra of the ring puckering vibration of chlorocyclobutane,c-C4H7Cl,bromocyclobutane,c-C4H7Br,and aminocyclobutane,c-C4H7NH2,have been utilized to obtain the potential function governing the ring inversion for these *** determined barriers to planarity are compared to those obtained from MP2(full) ab initio and density functional theory B3LYP calculations by utilizing a variety of basis *** all of these studies it is shown that the raman spectra are superior to the infrared spectra for determining the frequencies of the excited state transitions.

关键词：硅氧烷远红外光谱拉曼光谱密度泛函理论

Identifying associations between epidemiological entities in news data for animal disease surveillance

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Artificial Intelligence in Agriculture 2021年第1期5卷 163-174页

作者： sarah Valentin renaud Lancelot Mathieu roche CIrAD UMR ASTREUMR TETISF-34398 MontpellierFrance ASTrE Univ MontpellierCIRADINRAEMontpellierFrance TETIS Univ MontpellierAgroParisTechCIRADCNRSINRAEMontpellierFrance

Event-based surveillance systems are at the crossroads of human and animal(and plant and ecosystem)health,epidemiology,statistics,and ***,their deployment faces many challenges specific to each domain and their intersections,such as relations among automation,artificial intelligence,and *** this context,ourwork pertins to the extraction of epidemiological events in textual data(***)by unsupervised *** define the event extraction task as detecting pairs of epidemiological entities(e.g.a disease name and location).The quality of the ranked lists of pairs was evaluated using specific ranking evaluation *** used a publicly available annotated corpus of 438 documents(*** articles)related to animal disease *** statistical approach was able to detect event-related pairs of epidemiological features with a good trade-off between precision and *** results showed that using a window of words outperformed document-based and sentence-based approaches,while reducing the probability of detecting false *** results indicated that Mutual Information was less adapted than the Dice coefficient for ranking pairs of features in the event extraction *** believe that Mutual Information would be more relevant for rare pair detection(*** signals),but requires higher manual curation to avoid false positive extraction ***,generalising the country-level spatial features enabled better discrimination(***)of relevant disease-location pairs for event extraction.

关键词： Animal disease surveillance Text mining Event extraction

Transporters Contributing to Iron Trafficking in Plants

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Molecular Plant 2011年第3期4卷 464-476页

作者： sarah S. Conte Elsbeth L. Walker University of Massachusetts Amherst Biology Department 611 No. Pleasant St Amherst MA 01002 USA

This review will discuss recent progress in understanding the many roles of transporters in the whole-plant physiological processes that maintain iron （Fe） homeostasis. These processes include uptake from the soil via roots, control of transport from roots to above-ground parts of the plant, unloading of Fe from the xylem in above-ground parts, loading of Fe into mitochondria and plastids, transport of Fe to reproductive parts of the plant, and Fe mobilization during seed germination. In addition, we will discuss the mechanisms that plants use to cope with an apparently unintended conse- quence of Fe acquisition： the uptake of toxic heavy metals via Fe transporters. rapid progress has been made in under- standing the transport processes involved in each of these areas in the last 5 years and this review will focus on this recent progress. We will also highlight the key questions regarding transport steps that remain to be elucidated.

关键词： Nutrient and metal transport transporters gene regulation iron nicotianamine phytosiderophores.

The epidemiology of hyperferritinaemia

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World Journal of Gastroenterology 2006年第36期12卷 5866-5869页

作者： sarah Hearnshaw Nick Paul Thompson Andrew McGill Department of Gastroenterology The Freeman Hospital Freeman Road High Heaton Newcastle Upon Tyne Tyne and Wear NE7 7DN United Kingdom Department of Biochemistry Newcastle General Hospital Westgate Road Newcastle upon Tyne Tyne and Wear United Kingdom

AIM： To discover the causes of markedly raised ferritin levels in patients seen at a teaching hospital in Newcastle Upon Tyne, United Kingdom. METHODS： Demographic and medical data were collected for all patients over 18 years who had a serum ferritin levels recorded as ≥ 1500 μg/L during the period January to September 2002. The cause or causes for their hyperferritinaemia were identified from their medical notes. Patients from a defined local population were identified. rESULTS： A total of 19 583 measurements were provided of which 406 from 199 patients were ≥ 1500 μg/L. An annual incidence for the local population was determined to be 0.44/1000. 150/199 medical notes were scrutinised and 81 patients were identified as having a single cause for their raised ferritin level. The most common single cause was alcoholic liver disease in the local population and renal failure was the most common single cause in the overall population. Confirmed hereditary haemochromatosis was the 10^th most common cause. Liver disease contributed to hyperferritinaemia in 44% of the patients. Weight loss may have contributed to hyperferritinaemia in up to 11%. CONCLUSION： Alcohol related liver disease, haematological disease, renal failure and neoplasia are much more common causes of marked hyperferritinaemia than haemochromatosis. The role of weight loss in hyperferritinaemia may warrant further investigation.

关键词： Ferritin Epidemiology Haemochromatosis

Zika virus and neural developmental defects: building a case for a cause

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Science China(Life Sciences) 2016年第5期59卷 536-538页

作者： sarah C Ogden Christy Hammack Hengli Tang Department of Biological Science Florida State University

Zika virus （ZIKV）, a little-known .flavivirus until a few months ago, is currently at the forefront of public health concerns worldwide because of its suspected role in causing microcephaly and other developmental defects in fetuses of infected mothers. On February 1, 2016, the World Health Organization declared a Public Health Emergency of Inter- national Concern （PHEIC） for ZIKV. Discovered more than half a century ago in Uganda,

关键词：神经发育病毒缺陷事业世界卫生组织健康问题公共卫生乌干达

Continuous Mobile User Authentication Using a Hybrid CNN-Bi-LSTM Approach

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计算机、材料和连续体（英文） 2023年第4期75卷 651-667页

作者： sarah Alzahrani Joud Alderaan Dalya Alatawi Bandar Alotaibi Department of Information Technology University of TabukTabuk71491Saudi Arabia Sensor Networks and Cellular Systems research Center University of TabukTabuk71491Saudi Arabia

Internet of Things (IoT) devices incorporate a large amount ofdata in several fields, including those of medicine, business, and *** authentication is paramount in the IoT era to assure connecteddevices’ security. However, traditional authentication methods and conventionalbiometrics-based authentication approaches such as face recognition,fingerprints, and password are vulnerable to various attacks, including smudgeattacks, heat attacks, and shoulder surfing attacks. Behavioral biometrics isintroduced by the powerful sensing capabilities of IoT devices such as smartwearables and smartphones, enabling continuous authentication. ArtificialIntelligence (AI)-based approaches introduce a bright future in refining largeamounts of homogeneous biometric data to provide innovative user authenticationsolutions. This paper presents a new continuous passive authenticationapproach capable of learning the signatures of IoT users utilizing smartphonesensors such as a gyroscope, magnetometer, and accelerometer to recognizeusers by their physical activities. This approach integrates the convolutionalneural network (CNN) and recurrent neural network (rNN) models to learnsignatures of human activities from different users. A series of experiments areconducted using the MotionSense dataset to validate the effectiveness of theproposed method. Our technique offers a competitive verification accuracyequal to 98.4%.We compared the proposed method with several conventionalmachine learning and CNN models and found that our proposed modelachieves higher identification accuracy than the recently developed verificationsystems. The high accuracy achieved by the proposed method proves itseffectiveness in recognizing IoT users passively through their physical activitypatterns.

关键词： Human activity recognition recurrent neural network(rNN) internet of things(IoT) machine learning(ML)

Educational Videos Subtitles’Summarization Using Latent Dirichlet Allocation and Length Enhancement

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Computers, Materials & Continua 2022年第3期70卷 6205-6221页

作者： sarah S.Alrumiah Amal A.Al-Shargabi Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia

Nowadays,people use online resources such as educational videos and ***,such videos and courses are mostly long and thus,summarizing them will be *** video contents(visual,audio,and subtitles)could be analyzed to generate textual summaries,i.e.,***’subtitles contain significant ***,summarizing subtitles is effective to concentrate on the necessary *** of the existing studies used Term Frequency-Inverse Document Frequency(TF-IDF)and Latent Semantic Analysis(LSA)models to create lectures’*** study takes another approach and applies LatentDirichlet Allocation(LDA),which proved its effectiveness in document ***,the proposed LDA summarization model follows three *** first phase aims to prepare the subtitle file for modelling by performing some preprocessing steps,such as removing stop *** the second phase,the LDA model is trained on subtitles to generate the keywords list used to extract important *** in the third phase,a summary is generated based on the keywords *** generated summaries by LDA were lengthy;thus,a length enhancement method has been *** the evaluation,the authors developed manual summaries of the existing“EDUVSUM”educational videos *** authors compared the generated summaries with the manual-generated outlines using two methods,(i)recall-Oriented Understudy for Gisting Evaluation(rOUGE)and(ii)human *** performance of LDA-based generated summaries outperforms the summaries generated by TF-IDF and *** reducing the summaries’length,the proposed length enhancement method did improve the summaries’precision *** domains,such as news videos,can apply the proposed method for video summarization.

关键词： Subtitle summarization educational videos topic modelling LDA extractive summarization

The Janus of macrophysiology： stronger effects of evolutionary history, but weaker effects of climate on upper thermal limits are reversed for lower thermal limits in ants

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Current Zoology 2018年第2期64卷 223-230页

作者： sarah E. DIAMOND Lacy D. CHICK Department of Biology Case Western Reserve University Cleveland OH 44106 USA

Species may exhibit similar traits via different mechanisms： environmental filtering and local adaptation （geography） and shared evolutionary history （phylogeny） can each contribute to the resemblance of traits among species. Parsing trait variation into geographic and phylogenetic sources is important, as each suggests different constraints on trait evolution. Here, we explore how phylogenetic distance, geographic distance, and geographic variation in climate shape physiological tolerance of high and low temperatures using a global dataset of ant thermal tolerances. We found generally strong roles for evolutionary history and geographic variation in temperature, but essen- tially no detectable effects of spatial proximity per se on either upper or lower thermal tolerance. When we compared the relative importance of the factors shaping upper and lower tolerances, we found a much stronger role for evolutionary history in shaping upper versus lower tolerance, and a moderately weaker role for geographic variation in temperature in shaping upper tolerance when compared with lower tolerance. Our results demonstrate how geographic variation in climate and evolutionary history may have differential effects on the upper and lower endpoints of physiological tolerance. This Janus effect, where the relative contributions of geographic variation in climate and evolutionary history are reversed for lower versus upper physiological tolerances, has gained some support in the literature, and our results for ant physiological tolerances provide further evidence of this pa^ern. As the climate continues to change, the high phylogenetic conservatism of upper tolerance may suggest potential constraints on the evolution of tolerance of high temperatures.

关键词： biogeography evolutionary history latitudinal cline macrophysiology temperature thermal tolerance.