11,295 research outputs found

    Évaluation de l'impact du changement climatique sur la dĂ©foliation de l'Ă©pinette noire par la tordeuse des bourgeons de l'Ă©pinette

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    Les modĂšles Ă©cologiques actuels prĂ©voient de profonds effets des changements climatiques sur les rĂ©gimes de perturbations naturelles des forĂȘts. La tordeuse des bourgeons de l'Ă©pinette (Choristoneura fumiferana) (TBE) est le principal insecte dĂ©foliateur dans l'est de l'AmĂ©rique du Nord. Les Ă©pidĂ©mies de TBE ont un impact majeur sur la structure et la fonction de la forĂȘt borĂ©ale canadienne puisque la dĂ©foliation entraĂźne une diminution de la croissance des arbres, une augmentation de la mortalitĂ© et une baisse de la productivitĂ© forestiĂšre. Les Ă©pidĂ©mies de TBE sont devenues plus sĂ©vĂšres au cours du dernier siĂšcle Ă  cause des changements climatiques; cependant, nous savons peu de choses sur la maniĂšre dont l'effet intĂ©grĂ© du climat et du TBE modifie la croissance des espĂšces hĂŽtes. Nous Ă©valuons ici comment l’interaction entre le climat et la gravitĂ© de l'Ă©pidĂ©mie affecte la croissance de l'Ă©pinette noire (Picea mariana) pendant l'Ă©pidĂ©mie de TBE qui a eu lieu entre 1968-1988 et 2006-2017. Nous avons compilĂ© des sĂ©ries dendrochronologiques (2271 arbres), des donnĂ©es de sĂ©vĂ©ritĂ© de l'Ă©pidĂ©mie (estimĂ©e par la dĂ©foliation aĂ©rienne observĂ©e) et des donnĂ©es climatiques pour 164 sites au QuĂ©bec, Canada. Nous avons utilisĂ© un modĂšle linĂ©aire Ă  effets mixtes pour dĂ©terminer l'impact des paramĂštres climatiques, de la dĂ©foliation cumulative (des cinq annĂ©es prĂ©cĂ©dentes) et de leur effet couplĂ© sur la croissance en surface terriĂšre. À la gravitĂ© maximale de l'Ă©pidĂ©mie, la croissance en surface terriĂšre de l'Ă©pinette noire a Ă©tĂ© rĂ©duite de 14 Ă  18 % sur les cinq annĂ©es en raison de l'effet TBE. Cette croissance a Ă©tĂ© affectĂ©e par le climat : des tempĂ©ratures minimales estivales prĂ©cĂ©dentes plus Ă©levĂ©es et un indice d'humiditĂ© climatique estival plus Ă©levĂ© ont rĂ©duit la croissance de 11 % et 4 % respectivement. En revanche, l'effet nĂ©gatif de la dĂ©foliation a Ă©tĂ© attĂ©nuĂ© de 9% pour une tempĂ©rature minimale plus Ă©levĂ©e au printemps prĂ©cĂ©dent et de 7% pour une tempĂ©rature maximale plus Ă©levĂ©e l'Ă©tĂ© prĂ©cĂ©dent. Cette Ă©tude amĂ©liore notre comprĂ©hension des effets combinĂ©s de la TBE et du climat et aide Ă  prĂ©voir les dommages futurs causĂ©s par cet insecte dans les peuplements forestiers afin de soutenir la gestion durable des forĂȘts. Nous recommandons Ă©galement que les projections des Ă©cosystĂšmes dans la forĂȘt borĂ©ale incluent plusieurs classes de dĂ©foliation de la TBE et plusieurs scĂ©narios climatiques

    Integrative multi-omics analysis for the effect of genetic alterations in cancer xenograft and organoid models

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    Department of Biomedical EngineeringDNA damage is a well-recognized factor in the development and progression of cancer. Numerous studies on genetic changes associated with cancer or the DNA repair pathway have been conducted, however, there is still a need for additional research on their function. The establishment of patient-derived xenografts or organoids for the purpose of testing functional genomic approaches is the subject of ongoing research. According to model-specific characteristics, it is not fully understood how these attempts to simulate patient cancer differ from original cancer. To comprehend the distinction between genuine patient cancer and these patient-derived disease models in more depth, multi-omics analysis is required to comprehend the overall genotypes, phenotypes, and environmental variables. Depending on the characteristics of each disease model, distinct omics analysis approaches and factors must be considered. In addition, care must be taken to avoid technical errors when integrating omics data generated by different sequencing equipment. There is currently no golden rule for data integration, but several approaches are being developed. It is crucial to determine the function of genes linked with the DNA repair pathway because these genes contribute to the induction or prevention of cancer. In chapter 1, I identified the interaction between MRE11 and TRIP13 through proximity labeling combined with the SILAC method which is quantitative proteomics using metabolic labeling. TRIP13 depletion doesn???t affect the nuclease activity and conformation of the MRN complex but directly inhibits the interaction of MDC1 with MRN complex and MDC1 recruitment on the DNA damage site. TRIP13 degradation with mirin treatment shows additive effects on ATM signaling activation. In conclusion, TRIP13 regulates immediate-early DNA damage sensing through MRE11 and ATM signaling independently of mirin. When assessing the functional genomic approach using patient-derived disease models, it is essential to determine which aspects of the models' correlation to actual cancer should be properly considered. In chapter 2, I found there are a few overlapped deleterious somatic mutations of the PDX model and their original tumor. I suspected novel mutagen exposure during PDX establishment or sample contamination. However, germline mutations of PDX models are well conserved from original tumors, and their mutational signatures of PDX also mimic that of their tumor. Though the number of overlapped mutations between the PDX model and their tumor was few, brain tumor-specific mutations are found in PDX samples. Especially, histone methylation- and cilia-related gene mutations are enriched in PDX samples. While it suggested these mutated genes are needed for maintaining the stemness of brain tumor PDX model or PDX model would be more appropriate for the samples with high heterogeneity, I have presented precautions and considerations in PDX model genome analysis. Multi-omics analysis that takes into consideration genetic, expressive, and clinical aspects can provide important information for the study of diseases with complicated etiologies, such as cancer, and can contribute to the development of diagnosis and treatment. To utilize colorectal cancer organoids for Companion Diagnostics (CDx), in chapter 3, I characterized patient-derived colorectal cancer (CRC) organoids through well-known genomic markers such as Tumor mutation burden (TMB), Microsatellite instability (MSI) and propose a novel grouping method using sharing same mutation site. The classification of CRC patients was more detailed combined with consensus molecular subtype (CMS) classifications. Additionally, I extract the expression features of the patients who experience recurrence or metastasis after first-line chemotherapy treatment with reference to clinical data. Drug response of CRC organoids by patient group and knockdown of the extracted features in the selected organoids would be validated in further study. In summary, with this dissertation, I conducted functional research on the DNA repair pathway of cancer-related genes, as well as the genetic analysis between patient-derived xenograft and original tumors, and introduced a novel perspective on the diagnosis and treatment of colorectal cancer patients using patient-derived organoids through multi-omics analysis.ope

    Simultaneous assimilation of Fengyun-4A and Himawari-8 aerosol optical depth retrieval to improve air quality simulations during one storm event over East Asia

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    Aerosols are the main components of air pollutants, which are closely related to haze, dust storm and air pollution. In this study, an aerosol data assimilation system was developed using Gridpoint Statistical Interpolation (GSI) system to assimilate the Aerosol Optical Depth (AOD) observations from FY4 and Himawari-8 for the first time and applied in the heavy dust case over east Asia in March 2018. Three parallel experiments assimilated AOD from FY4, Himawari-8 and both the FY4 and Himawari-8 respectively and a control experiment which did not employ DA were performed. The hourly aerosol analyses and forecasts are compared with the assimilated FY-4 AOD, Himawari-8 AOD and independent AOD from Aerosol Robotic Network (AERONET). The results showed that all forms of DA experiments improved a low Bias and the RMSE reduced about 20%. The aerosol data assimilation with observations from both the FY-4 and Himawari-8 satellites substantially improved aerosol analyses and subsequent forecasts with more abundant aerosol observation information, especially over the northwest of China. This study indicates that the new generation geostationary meteorological satellites have potential to dramatically contribute to air quality forecasting

    Feeding Diversity of Finfish in Different Wild Habitat

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    Sonmiani Bay has unique faunal diversity and distribution especially finfish as mangroves provides an imperative ecosystem which offer the shelter and protection to the associated organisms and care of their juveniles in bay limits. This study aimed to evaluate the diversity pattern according to physical and physiological responses and feeding habits (carnivorous and herbivorous) of finfish species in accordance with current habitat conditions in the Sonmiani Bay. A total of 4499, individuals of comprising 155 finfish species that represent 50 families were captured by these four (beach seines, purse seines, gill nets, and cast nets) nets during a twelve-month survey in a year. The distribution pattern of finfishes captured classified into four groups (tidal visitors, permanent residents, partial residents, and seasonal visitors) according to their patterns of distribution. Understanding of the true feeding behavior of organisms needs a more reliable and functional approach. The feeding ecology is not only functional for food and feeding behavior of fish as usually described by various tools and techniques of analytical research to take up more reliable details to explain the feeding biology in fish but also the indicator of habitat quality and status

    Effects of the super-powerful tropospheric western Pacific phenomenon of September–October 2018 on the ionosphere over China: results from oblique sounding

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    Doppler measurements at oblique propagation paths from the city of Harbin, the People's Republic of China (PRC), to 10 high-frequency (HF) radio broadcast stations in the PRC, Japan, Mongolia, and the Republic of Korea captured the response in the ionosphere to the activity of the super typhoon, Typhoon Kong-rey, from 30 September to 6 October 2018. The Harbin Engineering University coherent software-defined radio system generates the database containing the complex amplitudes of the radio signals that have been acquired along 14 propagation paths since 2018. The complex amplitudes are used for calculating the temporal dependences of the Doppler spectra and signal amplitudes, and the Doppler spectra are used to plot the Doppler shift as a function of time, fD(t), for all rays. The scientific objectives of this study are to reveal the possible perturbations caused by the activity of Typhoon Kong-rey and to estimate the magnitudes of wave parameters of the ionospheric plasma and radio signals. The amplitudes, fDa, of the Doppler shift variations were observed to noticeably increase (factor of ∌2–3) on 1–2 and 5–6 October 2018, while the 20–120 min periods, T, of the Doppler shift variations suggest that the wavelike disturbances in the ionosphere are caused by atmospheric gravity waves. The periods and amplitudes of quasi-sinusoidal variations in the Doppler shift, which have been determined for all propagation paths, may be used to estimate the amplitudes, ÎŽNa, of quasi-sinusoidal variations in the electron density. Thus, T≈20 min and fDa≈0.1 Hz yield ÎŽNa≈0.4 %, whereas T≈30 min and fDa≈0.2 Hz give ÎŽNa≈1.2 %. If T≈60 min and fDa≈0.5 Hz, then ÎŽNa≈6 %. The periods T are found to change within the 15–120 min limits, and the Doppler shift amplitudes, fDa, show variability within the 0.05–0.4 Hz limits.</p

    Review of Methodologies to Assess Bridge Safety During and After Floods

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    This report summarizes a review of technologies used to monitor bridge scour with an emphasis on techniques appropriate for testing during and immediately after design flood conditions. The goal of this study is to identify potential technologies and strategies for Illinois Department of Transportation that may be used to enhance the reliability of bridge safety monitoring during floods from local to state levels. The research team conducted a literature review of technologies that have been explored by state departments of transportation (DOTs) and national agencies as well as state-of-the-art technologies that have not been extensively employed by DOTs. This review included informational interviews with representatives from DOTs and relevant industry organizations. Recommendations include considering (1) acquisition of tethered kneeboard or surf ski-mounted single-beam sonars for rapid deployment by local agencies, (2) acquisition of remote-controlled vessels mounted with single-beam and side-scan sonars for statewide deployment, (3) development of large-scale particle image velocimetry systems using remote-controlled drones for stream velocity and direction measurement during floods, (4) physical modeling to develop Illinois-specific hydrodynamic loading coefficients for Illinois bridges during flood conditions, and (5) development of holistic risk-based bridge assessment tools that incorporate structural, geotechnical, hydraulic, and scour measurements to provide rapid feedback for bridge closure decisions.IDOT-R27-SP50Ope

    Innate immunity and metabolism in the bovine ovarian follicle

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    Postpartum uterine disease in dairy cows is associated with reduced fertility. One of the first and most prevalent bacteria associated with uterine disease is Escherichia coli. The bacterial endotoxin, lipopolysaccharide (LPS), accumulates in the ovarian follicular fluid of animals with uterine disease. The granulosa cells of the ovarian follicle respond to LPS by secreting pro-inflammatory cytokines, such as interleukin (IL)-1a, IL-1b and IL-8, and oocyte health is perturbed. Dairy cows also experience metabolic energy stress in the postpartum period, which is associated with an increased risk of developing uterine disease and ovarian dysfunction. This thesis explored the crosstalk between innate immunity and metabolic energy stress in bovine granulosa cells and cumulus-oocyte complex. Firstly, we found that glycolysis, AMP-activated protein kinase and the mechanistic target of rapamycin, regulate the innate immune responses to LPS in granulosa cells isolated from bovine ovarian follicles. Activation of AMP-activated protein kinase decreased the LPS-induced secretion of IL-1a, IL-1b, and IL8, and was associated with shortened duration of ERK1/2 and JNK phosphorylation. Next, we found that decreasing the availability of cholesterol or inhibiting cholesterol biosynthesis using short-interfering RNA impaired the LPS-induced secretion of IL-1a and IL-1b by granulosa cells. Furthermore, metabolic energy stress or inhibiting cholesterol biosynthesis in the bovine cumulus-oocyte complex modulated the innate immune responses to LPS, and perturbed meiotic progression during in vitro maturation. Finally, we explored an in vivo model of uterine disease in heifers, using RNAseq to investigate alterations to the transcriptome of the reproductive tract. We found that uterine disease altered the transcriptome of the endometrium, oviduct, granulosa cells and oocyte, several months after bacterial infusion; these changes were most evident in the granulosa cells and oocyte of the ovarian follicle. The findings from this thesis imply that there is crosstalk between innate immunity and metabolism in the bovine ovarian follicle

    Annals [...].

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    Pedometrics: innovation in tropics; Legacy data: how turn it useful?; Advances in soil sensing; Pedometric guidelines to systematic soil surveys.Evento online. Coordenado por: Waldir de Carvalho Junior, Helena Saraiva Koenow Pinheiro, Ricardo SimĂŁo Diniz Dalmolin
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