Modeling and natural mode analysis of tethered multi-aircraft systems

Two complementary simulators aimed at the dynamic analysis of airborne wind energy systems based on multi-aircraft configurations are presented. The first model considers a train of stacked aircraft linked among them by two inelastic and massless tethers with no aerodynamic drag. The architecture of the mechanical system in the second simulator is configurable, as long as the system is made of a set of aircraft linked by an arbitrary number of elastic tethers. In both cases, the aircraft are modeled as rigid bodies and the controller is incorporated in the aerodynamic torque through the deflections of control surfaces. An analysis of the symmetric equilibrium state and the corresponding natural modes of a train (stacked configuration) of aircraft was carried out. It revealed that the higher the position of the aircraft in the train, the more they participate in the modes. Tether inertial and aerodynamic drag effects increase the equilibrium angles of attack of the aircraft and the tether tension at the attachment points. The potential applications and computational performance of the two codes are discussed.This work was supported by the Ministerio de Ciencia, Innovación y Universidades of Spain and the European Regional Development Fund under the GreenKite project ENE2015-69937-R (MINECO/FEDER, UE) and continued under the GreenKite-2 project funded by Agencia Estatal de Investigación (PID2019-110146RB-I00/ AEI / 10.13039/501100011033). GSA work is supported by the Ministerio de Ciencia, Innovación y Universidades of Spain under the Grant RYC-2014-15357

Australian Bat Lyssavirus: Analysis of National Bat Surveillance Data from 2010 to 2016

Australian bat lyssavirus (ABLV) was first described in 1996 and has been regularly detected in Australian bats since that time. While the virus does not cause population level impacts in bats and has minimal impacts on domestic animals, it does pose a public health risk. For this reason, bats are monitored for ABLV and a national dataset is collated and maintained by Wildlife Health Australia. The 2010–2016 dataset was analysed using logistic regression and time-series analysis to identify predictors of infection status in bats and the factors associated with human exposure to bats. In common with previous passive surveillance studies, we found that little red flying-foxes (Pteropus scapulatus) are more likely than other species to be infected with ABLV. In the four Australian mainland species of flying-fox, there are seasonal differences in infection risk that may be associated with reproductive cycles, with summer and autumn the seasons of greatest risk. The risk of human contact was also seasonal, with lower risk in winter. In line with other studies, we found that the circumstances in which the bat is encountered, such as exhibiting abnormal behaviour or being grounded, are risk factors for ABLV infection and human contact and should continue be key components of public health messaging. We also found evidence of biased recording of some types of information, which made interpretation of some findings more challenging. Strengthening of “One Health” linkages between public health and animal health services at the operational level could help overcome these biases in future, and greater harmonisation nationally would increase the value of the dataset

Adult Aedes albopictus in winter: implications for mosquito surveillance in southern Europe

Comment in The Lancet Planetary HealthWe acknowledge funding from the following projects: A systematic surveillance of vector mosquitoes for the control of mosquito-borne diseases in the Region of Attica, financed by the Region of Attica; E4Warning, financed by the EU's Horizon Europe research and innovation programme under grant agreement 101086640; and IDAlert, financed by the EU's Horizon Europe research and innovation programme under grant agreement 101057554. The funders had no role in study design, data collection and analysis, the decision to publish, or the preparation of this Comment. The code used to make the figure can be found at https://earth.bsc.es/gitlab/ghr/aedes-albopictus-winter.Peer ReviewedPostprint (author's final draft

Maximising response to postal questionnaires – A systematic review of randomised trials in health research

Background Postal self-completion questionnaires offer one of the least expensive modes of collecting patient based outcomes in health care research. The purpose of this review is to assess the efficacy of methods of increasing response to postal questionnaires in health care studies on patient populations. Methods The following databases were searched: Medline, Embase, CENTRAL, CDSR, PsycINFO, NRR and ZETOC. Reference lists of relevant reviews and relevant journals were hand searched. Inclusion criteria were randomised trials of strategies to improve questionnaire response in health care research on patient populations. Response rate was defined as the percentage of questionnaires returned after all follow-up efforts. Study quality was assessed by two independent reviewers. The Mantel-Haenszel method was used to calculate the pooled odds ratios. Results Thirteen studies reporting fifteen trials were included. Implementation of reminder letters and telephone contact had the most significant effect on response rates (odds ratio 3.7, 95% confidence interval 2.30 to 5.97 p = <0.00001). Shorter questionnaires also improved response rates to a lesser degree (odds ratio 1.4, 95% confidence interval 1.19 to 1.54). No evidence was found that incentives, re-ordering of questions or including an information brochure with the questionnaire confer any additional advantage. Conclusion Implementing repeat mailing strategies and/or telephone reminders may improve response to postal questionnaires in health care research. Making the questionnaire shorter may also improve response rates. There is a lack of evidence to suggest that incentives are useful. In the context of health care research all strategies to improve response to postal questionnaires require further evaluation

An integrative identification guide to the Hydrozoa (Cnidaria) of Bocas del Toro, Panama

This work is the first attempt to assess the biodiversity of the Hydrozoa in the Archipiélago de Bocas del Toro (Panamá, Caribbean Sea) using morphology and molecular taxonomy, and to produce field identification tools to help future identification and monitoring efforts in the area. We sampled, identified, vouchered, and barcoded 112 specimens of Hydrozoa from shallow coastal waters (0–22 m depth) in the Archipiélago de Bocas del Toro. The specimens belong to 70 taxa, of which 53 were identified at the species level, and 17 were identified at the genus or family level. We produced 64 sequences of the large ribosomal subunit of the mitochondrial RNA (mt lsu-rRNA, 16S), the genetic marker generally used for barcoding Hydrozoa. We updated the local checklist that now comprises 118 species, and produced 87 detailed taxon identification tables that display species descriptions augmented with pictures, geographic distribution (worldwide and in Bocas del Toro), GenBank accession numbers for the 16S mitochondrial gene, and a synopsis of the families they belong to

Exosomes derived from HIV-1-infected cells contain trans-activation response element RNA.

Exosomes are nano-sized vesicles produced by healthy and virus-infected cells. Exosomes derived from infected cells have been shown to contain viral microRNAs (miRNAs). HIV-1 encodes its own miRNAs that regulate viral and host gene expression. The most abundant HIV-1-derived miRNA, first reported by us and later by others using deep sequencing, is the trans-activation response element (TAR) miRNA. In this study, we demonstrate the presence of TAR RNA in exosomes from cell culture supernatants of HIV-1-infected cells and patient sera. TAR miRNA was not in Ago2 complexes outside the exosomes but enclosed within the exosomes. We detected the host miRNA machinery proteins Dicer and Drosha in exosomes from infected cells. We report that transport of TAR RNA from the nucleus into exosomes is a CRM1 (chromosome region maintenance 1)-dependent active process. Prior exposure of naive cells to exosomes from infected cells increased susceptibility of the recipient cells to HIV-1 infection. Exosomal TAR RNA down-regulated apoptosis by lowering Bim and Cdk9 proteins in recipient cells. We found 104–106 copies/ml TAR RNA in exosomes derived from infected culture supernatants and 103 copies/ml TAR RNA in the serum exosomes of highly active antiretroviral therapy-treated patients or long term nonprogressors. Taken together, our experiments demonstrated that HIV-1-infected cells produced exosomes that are uniquely characterized by their proteomic and RNA profiles that may contribute to disease pathology in AIDS

GeV Gamma-Ray Attenuation and the High-Redshift UV Background

We present new calculations of the evolving UV background out to the epoch of cosmological reionization and make predictions for the amount of GeV gamma-ray attenuation by electron-positron pair production. Our results are based on recent semi-analytic models of galaxy formation, which provide predictions of the dust-extinguished UV radiation field due to starlight, and empirical estimates of the contribution due to quasars. We account for the reprocessing of ionizing photons by the intergalactic medium. We test whether our models can reproduce estimates of the ionizing background at high redshift from flux decrement analysis and proximity effect measurements from quasar spectra, and identify a range of models that can satisfy these constraints. Pair-production against soft diffuse photons leads to a spectral cutoff feature for gamma rays observed between 10 and 100 GeV. This cutoff varies with redshift and the assumed star formation and quasar evolution models. We find only negligible amounts of absorption for gamma rays observed below 10 GeV for any emission redshift. With observations of high-redshift sources in sufficient numbers by the Fermi Gamma-ray Space Telescope and new ground-based instruments it should be possible to constrain the extragalactic background light in the UV and optical portion of the spectrum.Comment: 19 pages, 12 figures, Accepted for publication in MNRAS, this version includes minor correction

Galaxy Properties from the Ultra-violet to the Far-Infrared: Lambda-CDM models confront observations

We combine a semi-analytic model of galaxy formation with simple analytic recipes describing the absorption and re-emission of starlight by dust in the interstellar medium of galaxies. We use the resulting models to predict galaxy counts and luminosity functions from the far-ultraviolet to the sub-mm, from redshift five to the present, and compare with an extensive compilation of observations. We find that in order to reproduce the rest-UV and optical luminosity functions at high redshift, we must assume an evolving normalization in the dust-to-metal ratio, implying that galaxies of a given bolometric luminosity (or metal column density) must be less extinguished than their local counterparts. In our best-fit model, we find remarkably good agreement with observations from rest-frame 1500 Angstroms to 250 microns. At longer wavelengths, most dramatically in the sub-mm, our models underpredict the number of bright galaxies by a large factor. The models reproduce the observed total IR luminosity function fairly well. We show the results of varying several ingredients of the models, including various aspects of the dust attenuation recipe, the dust emission templates, and the cosmology. We use our models to predict the integrated Extragalactic Background Light (EBL), and compare with an observationally-motivated EBL model and with other available observational constraints.Comment: 27 pages, 17 figures, 1 table, accepted to MNRAS, this version matches accepted manuscrip

Profiles in Community-Engaged Learning

To provide a snapshot of the many impressive manifestations of community-engaged learning at the University of San Francisco, a 2014-2015 Faculty Learning Community (FLC), supported by the Center for Teaching Excellence (CTE), has collected the following profiles of selected faculty members across all the schools and colleges. This report was prepared by members of the CTE’s Faculty Learning Community on Community-Engaged Learning: Kevin D. Lo, Facilitator (School of Management), Emma Fuentes (School of Education), David Holler (College of Arts and Sciences), Tim Iglesias (School of Law), Susan Roberta Katz (School of Education), Star Moore (Leo T. McCarthy Center for Public Service and the Common Good), Chenit Ong-Flaherty (School of Nursing and Health Professions), Jennifer Parlamis (School of Management) Susan Pauly-O’Neill (School of Nursing and Health Professions). Our intent with this report is to offer USF administrators and incoming faculty members a sense of what’s being done well in community-engaged learning (CEL), while also pointing out what challenges remain as we establish our identity as a university that prioritizes community engagement. (Incidentally, we prefer the term “community-engaged learning” to “service-learning,” which we feel more precisely defines the scope of our activities. For more about this designation, please see the Executive Report on Community Engaged Learning issued by this same committee in June 2015.) Community-engaged learning as defined by Eyler and Giles is “a form of experiential education where learning occurs through a cycle of action and reflection as students . . . seek to achieve real objectives for the community and deeper understanding and skills for themselves. In the process, students link personal and social development with academic and cognitive development . . . experience enhances understanding; understanding leads to more effective action.” (qtd. in Bandy, Vanderbilt Center for Teaching, “What Is Service Learning or Community Engagement?”). We invited at least two faculty members from each school/college to answer several questions about the application of CEL in their courses. After providing a brief overview of activities in each course, we asked each professor what works well and what challenges persist. The successes and the challenges, as you’ll see, vary widely, and yet they clearly delineate, limited though our present sample size is, the great variety and energy and commitment our faculty have demonstrated in working with community partners and students. It is our hope that this report is merely the beginning of a much more ambitious project to be taken up by the McCarthy Center which will provide many more profiles of professors in the months and years to come