Reflectance properties of selected arctic-boreal land cover types: field measurements and their application in remote sensing

International audienceWe developed a mobile remote sensing measurement facility for spectral and anisotropic reflectance measurements. We measured reflection properties (BRF) of over 100 samples from most common land cover types in boreal and subarctic regions. This extensive data set serves as a unique reference opportunity for developing interpretation algorithms for remotely sensed materials as well as for modelling climatic effects in the boreal and subarctic zones. Our goniometric measurements show that the reflectances of the most common land cover types in the boreal and subarctic region can differ from each other by a factor of 100. Some types are strong forward scatterers, some backward scatterers, some reflect specularly, some have strong colours, some are bright in visual, some in infrared. We noted that spatial variations in reflectance, even among the same type of vegetation, can be well over 20%, diurnal variations of the same order and seasonal variation often over a factor of 10. This has significant consequences on the interpretation of satellite and airborne images and on the development of radiation regime models in both optical remote sensing and climate change research. We propose that the accuracy of optical remote sensing can be improved by an order of magnitude, if better physical reflectance models can be introduced. Further improvements can be reached by more optimised design of sensors and orbits/flight lines, by the effective combining of several data sources and better processing of atmospheric effects. We conclude that more extensive and systematic laboratory experiments and field measurements are needed, with more modelling effort

Lung macrophage scavenger receptor SR-A6 (MARCO) is an adenovirus type-specific virus entry receptor

<div><p>Macrophages are a diverse group of phagocytic cells acting in host protection against stress, injury, and pathogens. Here, we show that the scavenger receptor SR-A6 is an entry receptor for human adenoviruses in murine alveolar macrophage-like MPI cells, and important for production of type I interferon. Scavenger receptors contribute to the clearance of endogenous proteins, lipoproteins and pathogens. Knockout of SR-A6 in MPI cells, anti-SR-A6 antibody or the soluble extracellular SR-A6 domain reduced adenovirus type-C5 (HAdV-C5) binding and transduction. Expression of murine SR-A6, and to a lower extent human SR-A6 boosted virion binding to human cells and transduction. Virion clustering by soluble SR-A6 and proximity localization with SR-A6 on MPI cells suggested direct adenovirus interaction with SR-A6. Deletion of the negatively charged hypervariable region 1 (HVR1) of hexon reduced HAdV-C5 binding and transduction, implying that the viral ligand for SR-A6 is hexon. SR-A6 facilitated macrophage entry of HAdV-B35 and HAdV-D26, two important vectors for transduction of hematopoietic cells and human vaccination. The study highlights the importance of scavenger receptors in innate immunity against human viruses.</p></div

Arenavirus budding resulting from viral-protein-associated cell membrane curvature

Viral replication occurs within cells, with release (and onward infection) primarily achieved through two alternative mechanisms: lysis, in which virions emerge as the infected cell dies and bursts open; or budding, in which virions emerge gradually from a still living cell by appropriating a small part of the cell membrane. Virus budding is a poorly understood process that challenges current models of vesicle formation. Here, a plausible mechanism for arenavirus budding is presented, building on recent evidence that viral proteins embed in the inner lipid layer of the cell membrane. Experimental results confirm that viral protein is associated with increased membrane curvature, whereas a mathematical model is used to show that localized increases in curvature alone are sufficient to generate viral buds. The magnitude of the protein-induced curvature is calculated from the size of the amphipathic region hypothetically removed from the inner membrane as a result of translation, with a change in membrane stiffness estimated from observed differences in virion deformation as a result of protein depletion. Numerical results are based on experimental data and estimates for three arenaviruses, but the mechanisms described are more broadly applicable. The hypothesized mechanism is shown to be sufficient to generate spontaneous budding that matches well both qualitatively and quantitatively with experimental observations

A controlled follow-up study of adolescents exposed to a school shooting - Psychological consequences after four months

Background: In November 2007, a student shot eight people and himself at Jokela High School, Finland. This study aims to evaluate the long-term effects of exposure to a school shooting among adolescents. Method: Associations between psychological outcomes and background factors were analysed and compared with "comparison students" four months after the incident. A questionnaire including Impact of Event Scale (IES) and General Health Questionnaire (GHQ-36) was used. Results: Half of the females and a third of the males suffered from posttraumatic distress. High level of posttraumatic distress (IES >= 35), predicting PTSD, was observed in 27% of the females and 7% of the males. The odds ratio was 6.4 (95% confidence interval 3.5-10.5) for having high levels of posttraumatic distress. Severe or extreme exposure and female gender were found to increase the risk. Forty-two percent of the females and 16% of the males had psychiatric disturbance (GHQ >= 9). Severe or extreme exposure, older age and female gender increased the risk. Perceived support from family and friends was found to be protective. Conclusions: The observed risk and protective factors were similar to earlier studies. Follow-up will be essential in identifying factors predicting persisting trauma-related symptoms in adolescence. (C) 2010 Elsevier Masson SAS. All rights reserved.Peer reviewe

Genetics of decayed sexual traits in a parasitoid wasp with endosymbiont-induced asexuality.

Trait decay may occur when selective pressures shift, owing to changes in environment or life style, rendering formerly adaptive traits non-functional or even maladaptive. It remains largely unknown if such decay would stem from multiple mutations with small effects or rather involve few loci with major phenotypic effects. Here, we investigate the decay of female sexual traits, and the genetic causes thereof, in a transition from haplodiploid sexual reproduction to endosymbiont-induced asexual reproduction in the parasitoid wasp Asobara japonica. We take advantage of the fact that asexual females cured of their endosymbionts produce sons instead of daughters, and that these sons can be crossed with sexual females. By combining behavioral experiments with crosses designed to introgress alleles from the asexual into the sexual genome, we found that sexual attractiveness, mating, egg fertilization and plastic adjustment of offspring sex ratio (in response to variation in local mate competition) are decayed in asexual A. japonica females. Furthermore, introgression experiments revealed that the propensity for cured asexual females to produce only sons (because of decayed sexual attractiveness, mating behavior and/or egg fertilization) is likely caused by recessive genetic effects at a single locus. Recessive effects were also found to cause decay of plastic sex-ratio adjustment under variable levels of local mate competition. Our results suggest that few recessive mutations drive decay of female sexual traits, at least in asexual species deriving from haplodiploid sexual ancestors

”Nyt ku ollaan vähän niinku jaettu porukoita, niin tuntuu sillä tavalla helpommalta”:2. luokan oppilaiden ja opettajien kokemuksia kahdesta pedagogisesta toimintamallista

Tiivistelmä. Opetuskulttuuri on hitaasti muuttuvaa. Vaikka vuoden 2014 Perusopetuksen opetussuunnitelman perusteet ohjaa entistä eheyttävämpään opetukseen, on pedagogisten toimintamallien muutokseen käytännön tasolla varattava aikaa. Eheytetyn, kokonaisvaltaisen opetuksen vastakohdaksi nähdään Suomessa perinteisesti vuosikymmeniä toteutettu oppiainejakoisen opetuksen malli. Konstruktivistista, kokonaisvaltaista oppimiskäsitystä pyritään ilmentämään opetussuunnitelman lisäksi fyysisellä ympäristöllä. Uusien, jo rakennettujen ja rakenteilla olevien koulujen oppimisympäristö pyrkii tukemaan yhteisöllistä ja eheyttävää oppimiskäsitystä muun muassa arkkitehtuurisilla valinnoillaan. Oppilaat ja opettajat voivat työskennellä jopa sadalle henkilölle mitoitetuissa yhteisissä tiloissa. Tämä pro gradu -tutkimus on toteutettu erään uuden koulun 2. -luokkien solussa. Tutkimuskohteessa kolme 2. -luokkaa toteutti syyslukukaudella 2016 yhteisessä tilassa yhteisöllistä ja oppiainerajatonta opetusta. Lukuvuoden 2017 keväällä tila jaettiin osiin ja toimintaa muutettiin oppiainejakoisempaan ja opettajajohtoisempaan malliin, jossa oltiin pääosin oman luokan kesken. Toive oli noussut oppilaiden ja kotiväen kautta. Tutkimuskysymykset ovat: Minkälaisia kokemuksia oppilailla ja opettajilla on syksyn koulunkäynnistä verrattuna kevään koulunkäyntiin? Miksi eheytetyn, yhteisöllisen luokkatoiminnan mallista luovuttiin ja palattiin perinteisempään luokka- ja oppiainejakoiseen malliin? Tutkimus on metodologialtaan fenomenografinen tapaustutkimus. Tutkimuksen aineisto kerättiin oppilaita haastatellen ja näin selvittäen kokemuksia syys- ja kevätlukukauden pedagogisista toimintamalleista. Myös opettajia haastateltiin sekä syksyllä että keväällä, jolloin oppilailta kerättyyn aineistoon saatiin mukaan aikuisen mielipide ja näkökulma vastauksia täydentämään. Tutkimuksen teoreettisessa osassa perehdytään alkuopetusikäisen oppijan kehitykseen ja niihin oppimiskäsityksiin, jotka ovat ohjanneet ja ohjaavat Suomen peruskoulun opetuskulttuuria ja oppimisympäristöjä. Tarkastelun kohteena ovat erityisesti opetuksen eheyttäminen ja kokonaisvaltainen oppiminen, johon vuoden 2014 opetussuunnitelman perusteet opettajia ja kouluja kannustaa. Lisäksi määritellään oppimisympäristön käsite. Oppimisympäristö laajassa merkityksessään on kuvattu sosiaalisen, psyykkisen ja fyysisen oppimisympäristön näkökulmista, ja tämä jaottelu ohjaa myös tulosten analysointia. Tutkimuksen tulosten mukaan oppilaat kokivat sosiaalisen oppimisympäristön syksyllä liian laajana, ja sosiaaliseen ympäristöön liittyi erityisesti työrauhan merkitys. Työrauhan koettiin keväällä parantuneen verrattuna syksyyn. Sosiaalinen oppimisympäristö koettiin keväällä kooltaan miellyttävämpänä ja turvallisempana kuin syksyllä, kun oppilaat siirtyivät toimimaan pääasiassa omien luokkien parissa. Merkitseviä olivat lisäksi psyykkisen ja fyysisen oppimisympäristön osa-alueet. Psyykkisestä ympäristöstä erityisen tärkeäksi oppilaat kokivat valinnan vapauden, jota kevätlukukaudella koettiin olevan enemmän kuin syksyn toimintamallissa. Tämä pro gradu -tutkimus käsittelee yhtä tapausta, mutta antaa näkökulmaa myös yhteiskunnallisella tasolla. Uudet koulut ovat usein moduuli- ja yhtenäiskouluja, joiden rakentaminen perustuu erityisesti yhteisöllisen ja laaja-alaisen oppimisen käsityksiin. Tämä tutkimus kuvaa alkuopetusikäisten oppilaiden ja opettajien kokemuksia siitä, millaista on toimia perinteisten luokkien sijaan yhdessä, yhteisessä tilassa

Analysis of User Preferences for Robot Motions in Immersive Telepresence

AbstractThis paper considers how the motions of a telepresence robot moving autonomously affect a person immersed in the robot through a head-mounted display. In particular, we explore the preference, comfort, and naturalness of elements of piecewise linear paths compared to the same elements on a smooth path. In a user study, thirty-six subjects watched panoramic videos of three different paths through a simulated museum in virtual reality and responded to questionnaires regarding each path. Preference for a particular path was influenced the most by comfort, forward speed, and characteristics of the turns. Preference was also strongly associated with the users’ perceived naturalness, which was primarily determined by the ability to see salient objects, the distance to the walls and objects, as well as the turns. Participants favored the paths that had a one meter per second forward speed and rated the path with the least amount of turns as the most comfortable.Abstract This paper considers how the motions of a telepresence robot moving autonomously affect a person immersed in the robot through a head-mounted display. In particular, we explore the preference, comfort, and naturalness of elements of piecewise linear paths compared to the same elements on a smooth path. In a user study, thirty-six subjects watched panoramic videos of three different paths through a simulated museum in virtual reality and responded to questionnaires regarding each path. Preference for a particular path was influenced the most by comfort, forward speed, and characteristics of the turns. Preference was also strongly associated with the users’ perceived naturalness, which was primarily determined by the ability to see salient objects, the distance to the walls and objects, as well as the turns. Participants favored the paths that had a one meter per second forward speed and rated the path with the least amount of turns as the most comfortable

Yeast : the soul of beer’s aroma—a review of flavour-active esters and higher alcohols produced by the brewing yeast

Among the most important factors influencing beer quality is the presence of well-adjusted amounts of higher alcohols and esters. Thus, a heavy body of literature focuses on these substances and on the parameters influencing their production by the brewing yeast. Additionally, the complex metabolic pathways involved in their synthesis require special attention. More than a century of data, mainly in genetic and proteomic fields, has built up enough information to describe in detail each step in the pathway for the synthesis of higher alcohols and their esters, but there is still place for more. Higher alcohols are formed either by anabolism or catabolism (Ehrlich pathway) of amino acids. Esters are formed by enzymatic condensation of organic acids and alcohols. The current paper reviews the up-to-date knowledge in the pathways involving the synthesis of higher alcohols and esters by brewing yeasts. Fermentation parameters affecting yeast response during biosynthesis of these aromatic substances are also fully reviewed.Eduardo Pires gratefully acknowledges the Fundacao para a Ciencia e a Tecnologia (FCT, Portugal) for the PhD fellowship support (SFRH/BD/61777/2009). The financial contributions of the EU FP7 project Ecoefficient Biodegradable Composite Advanced Packaging (EcoBioCAP, grant agreement no. 265669) as well as of the Grant Agency of the Czech Republic (project GACR P503/12/1424) are also gratefully acknowledged. The authors thank the Ministry of Education, Youth and Sports of the Czech Republic (MSM 6046137305) for their financial support