1,867 research outputs found

    Experiments with a spectral tropical cyclone model

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    July, 1983.Includes bibliographical references.Sponsored by the National Science Foundation ATM-8207563.Sponsored by the Office of Naval Research N00014-83-K-0068

    PHURIE : hurricane intensity estimation from infrared satellite imagery using machine learning

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    Automated prediction of hurricane intensity from satellite infrared imagery is a challenging problem with implications in weather forecasting and disaster planning. In this work, a novel machine learning-based method for estimation of intensity or maximum sustained wind speed of tropical cyclones over their life cycle is presented. The approach is based on a support vector regression model over novel statistical features of infrared images of a hurricane. Specifically, the features characterize the degree of uniformity in various temperature bands of a hurricane. Performance of several machine learning methods such as ordinary least squares regression, backpropagation neural networks and XGBoost regression has been compared using these features under different experimental setups for the task. Kernelized support vector regression resulted in the lowest prediction error between true and predicted hurricane intensities (approximately 10 knots or 18.5 km/h), which is better than previously proposed techniques and comparable to SATCON consensus. The performance of the proposed scheme has also been analyzed with respect to errors in annotation of center of the hurricane and aircraft reconnaissance data. The source code and webserver implementation of the proposed method called PHURIE (PIEAS HURricane Intensity Estimator) is available at the URL: http://faculty.pieas.edu.pk/fayyaz/software.html#PHURIE

    Applying Satellite Observations of Tropical Cyclone Internal Structures to Rapid Intensification Forecast With Machine Learning

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    Tropical cyclone (TC) intensity change is controlled by both environmental conditions and internal storm processes. We show that TC 24‐hr subsequent intensity change (DV24) is linearly correlated with the departures in satellite observations of inner‐core precipitation, ice water content, and outflow temperature from respective threshold values corresponding to neutral TCs of nearly constant intensity. The threshold values vary linearly with TC intensity. Using machine learning with the inner‐core precipitation and the predictors currently employed at the National Hurricane Center (NHC) for probabilistic rapid intensification (RI) forecast guidance, our model outperforms the NHC operational RI consensus in terms of the Peirce Skill Score for RI in the Atlantic basin during 2009–2014 by 37%, 12%, and 138% for DV24 ≥ 25, 30, and 35 kt, respectively. Our probability of detection is 40%, 60%, and 200% higher than the operational RI consensus, while the false alarm ratio is only 4%, 7%, and 6% higher

    Analysis of Hurricanes Using Long-Range Lightning Detection Networks

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    The new GOES-R satellite will be equipped with the Geostationary Lightning Mapper (GLM) that will provide unprecedented total lightning data with the potential to improve hurricane intensity forecasts. Past studies have provided conflicting interpretations of the role that lightning plays in forecasting tropical cyclone (TC) intensity changes. With the goal of improving the usefulness of total lightning, detailed case studies were conducted of five TCs that underwent rapid intensification (RI) within the domains of two unique ground-based long-range lightning detection networks, the World Wide Lightning Location Network (WWLLN) and Earth Networks Total Lightning Network (ENTLN). This analysis will provide greater details of the distribution of lightning within predefined storm features to highlight specific phenomena that large statistical studies cannot resolve.Both WWLLN and ENTLN datasets showed similar spatial and temporal patterns in lightning that validates the independent use of either network for analysis. For the cases examined, a maxima in eyewall lightning was located downshear and in the front-right quadrants relative to storm motion. Results show that RI follows a burst of lightning in the eyewall when coinciding with a period of little environmental vertical shear. Eyewall lightning would cycle with greater frequency during intensification compared to weakening. Bursts of lightning were observed in the eyewall just prior to eye formation in both the infrared and microwave imagery. Eyewall lightning bursts in low shear environments could be used to indicate intensification and improve forecasts.University Libraries Undergraduate Research Awardundergraduat

    Large-scale transdisciplinary collaboration for adaptation research: Challenges and insights

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    An increasing number of research programs seek to support adaptation to climate change through the engagement of large-scale transdisciplinary networks that span countries and continents. While transdisciplinary research processes have been a topic of reflection, practice, and refinement for some time, these trends now mean that the global change research community needs to reflect and learn how to pursue collaborative research on a large scale. This paper shares insights from a seven-year climate change adaptation research program that supports collaboration between more than 450 researchers and practitioners across four consortia and 17 countries. The experience confirms the importance of attention to careful design for transdisciplinary collaboration, but also highlights that this alone is not enough. The success of well-designed transdisciplinary research processes is also strongly influenced by relational and systemic features of collaborative relationships. Relational features include interpersonal trust, mutual respect, and leadership styles, while systemic features include legal partnership agreements, power asymmetries between partners, and institutional values and cultures. In the new arena of large-scale collaborative science efforts, enablers of transdisciplinary collaboration include dedicated project coordinators, leaders at multiple levels, and the availability of small amounts of flexible funds to enable nimble responses to opportunities and unexpected collaborations

    Tetraspanin CD53 promotes lymphocyte recirculation by stablising L-selectin surface expression

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    Tetraspanins regulate key processes in immune cells; however, the function of the leukocyterestricted tetraspanin, CD53 has remained unknown. Here we show that CD53 is essential for lymphocyte recirculation. Lymph nodes of Cd53-/- mice were smaller than wild-type mice due to a marked reduction in B cells and a 50% decrease in T cells. This reduced cellularity reflected an inability of Cd53-/- B and T cells to efficiently home to lymph nodes, due to the near absence of L-selectin from Cd53-/- B cells and reduced stability of L-selectin on Cd53-/- T cells. Further analyses, including on human lymphocytes, showed that CD53 inhibits L-selectin shedding via both ADAM17-dependent and -independent mechanisms. The disruption in lymphocyte recirculation in Cd53-/- mice led to impaired immune responses dependent on antigen delivery to lymph nodes. Together these findings demonstrate a previously unrecognized essential role for CD53 in lymphocyte trafficking and immune responses

    Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464– H2476

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    . Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464-H2476, 2000.-Our goal was to establish normal values for quantitative color kinesis indexes of left ventricular (LV) wall motion over a wide range of ages, which are required for objective diagnosis of regional systolic and diastolic dysfunction. Color-encoded images were obtained in 194 normal subjects (95 males, 99 females, age 2 mo to 79 yr) in four standard views. Quantitative indexes of magnitude and timing of systolic and diastolic function were studied for age-and genderrelated differences. Normal limits of all ejection and filling indexes were in a narrow range (Յ25% of the mean), with no major gender-related differences. Despite invariable ejection fractions, both peak filling and ejection rates decreased with age (30 and 20%, correspondingly) with a concomitant increase in mean filling and ejection times, resulting in fiveand twofold increases in the late to early filling and ejection ratios, correspondingly. Diastolic asynchrony increased with age (from 4.7 Ϯ 2.0 to 6.4 Ϯ 3.2 from the 2nd to 7th decade). The normal values of color kinesis indexes should allow objective detection of regional LV systolic and diastolic dysfunction. echocardiography; ultrasound imaging; ventricular function; wall motion COLOR KINESIS IS AN EMERGING echocardiographic technique based on acoustic quantification, which uses color-encoding to depict left ventricular (LV) systolic and diastolic endocardial motion However, a new technique, which detects abnormalities by comparing individual patient's data with normal values, relies on having these normal values established in a large sample of the normal population. Accordingly, normal values of different indexes of magnitude and timing of global and regional LV function derived from color kinesis images need to be established to allow objective detection of abnormalities with a high level of confidence. We also hypothesized that these indexes may be age and gender dependent, in which case normal values would need to be established for different demographic groups. Accordingly, the purpose of this collaborative multicenter effort was to establish normal values for magnitude and timing indexes of wall motion by acquiring and analyzing systolic and diastolic color kinesis images in a large group of normal subjects of both sexes over a wide range of ages. METHODS Study population. The protocol for this study was approved by the Institutional Review Board of the University of Chicago (protocol #9171). This protocol was initially designed to include eight age groups (8 decades between 0 and 80 yr) with a minimum of 20 normal subjects each (50% males and 50% Address for reprint requests and othe

    The Role of Inflammatory Mediators in the Pathogenesis of Otitis Media and Sequelae

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    This review deals with the characteristics of various inflammatory mediators identified in the middle ear during otitis media and in cholesteatoma. The role of each inflammatory mediator in the pathogenesis of otitis media and cholesteatoma has been discussed. Further, the relation of each inflammatory mediator to the pathophysiology of the middle and inner ear along with its mechanisms of pathological change has been described. The mechanisms of hearing loss including sensorineural hearing loss (SNHL) as a sequela of otitis media are also discussed. The passage of inflammatory mediators through the round window membrane into the scala tympani is indicated. In an experimental animal model, an application of cytokines and lipopolysaccharide (LPS), a bacterial toxin, on the round window membrane induced sensorineural hearing loss as identified through auditory brainstem response threshold shifts. An increase in permeability of the blood-labyrinth barrier (BLB) was observed following application of these inflammatory mediators and LPS. The leakage of the blood components into the lateral wall of the cochlea through an increase in BLB permeability appears to be related to the sensorineural hearing loss by hindering K+ recycling through the lateral wall disrupting the ion homeostasis of the endolymph. Further studies on the roles of various inflammatory mediators and bacterial toxins in inducing the sensorineumral hearing loss in otitis media should be pursued

    Consensus guidelines for the detection of immunogenic cell death

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    none82siApoptotic cells have long been considered as intrinsically tolerogenic or unable to elicit immune responses specific for dead cell-associated antigens. However, multiple stimuli can trigger a functionally peculiar type of apoptotic demise that does not go unnoticed by the adaptive arm of the immune system, which we named "immunogenic cell death" (ICD). ICD is preceded or accompanied by the emission of a series of immunostimulatory damage-associated molecular patterns (DAMPs) in a precise spatiotemporal configuration. Several anticancer agents that have been successfully employed in the clinic for decades, including various chemotherapeutics and radiotherapy, can elicit ICD. Moreover, defects in the components that underlie the capacity of the immune system to perceive cell death as immunogenic negatively influence disease outcome among cancer patients treated with ICD inducers. Thus, ICD has profound clinical and therapeutic implications. Unfortunately, the gold-standard approach to detect ICD relies on vaccination experiments involving immunocompetent murine models and syngeneic cancer cells, an approach that is incompatible with large screening campaigns. Here, we outline strategies conceived to detect surrogate markers of ICD in vitro and to screen large chemical libraries for putative ICD inducers, based on a high-content, high-throughput platform that we recently developed. Such a platform allows for the detection of multiple DAMPs, like cell surface-exposed calreticulin, extracellular ATP and high mobility group box 1 (HMGB1), and/or the processes that underlie their emission, such as endoplasmic reticulum stress, autophagy and necrotic plasma membrane permeabilization. We surmise that this technology will facilitate the development of next-generation anticancer regimens, which kill malignant cells and simultaneously convert them into a cancer-specific therapeutic vaccine.Kepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong-Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean-Ehrland; Riganti, Chiara; Rovere-Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei-Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, LorenzoKepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean Ehrland; Riganti, Chiara; Rovere Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenz

    Clinical development of new drug-radiotherapy combinations.

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    In countries with the best cancer outcomes, approximately 60% of patients receive radiotherapy as part of their treatment, which is one of the most cost-effective cancer treatments. Notably, around 40% of cancer cures include the use of radiotherapy, either as a single modality or combined with other treatments. Radiotherapy can provide enormous benefit to patients with cancer. In the past decade, significant technical advances, such as image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic radiotherapy, and proton therapy enable higher doses of radiotherapy to be delivered to the tumour with significantly lower doses to normal surrounding tissues. However, apart from the combination of traditional cytotoxic chemotherapy with radiotherapy, little progress has been made in identifying and defining optimal targeted therapy and radiotherapy combinations to improve the efficacy of cancer treatment. The National Cancer Research Institute Clinical and Translational Radiotherapy Research Working Group (CTRad) formed a Joint Working Group with representatives from academia, industry, patient groups and regulatory bodies to address this lack of progress and to publish recommendations for future clinical research. Herein, we highlight the Working Group's consensus recommendations to increase the number of novel drugs being successfully registered in combination with radiotherapy to improve clinical outcomes for patients with cancer.National Institute for Health ResearchThis is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/nrclinonc.2016.7
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