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

Mentoritoiminta Kesäyrittäjä-kampanjassa

Tiivistelmä. Muuttuvien työolosuhteiden sekä kansantaloudellisten haasteiden takia yrittäjyys nähdään keinona tuottaa yhteiskuntaan hyvinvointia sekä toimeliaisuutta. Yrittäjyyskasvatuksen avulla tuetaan nuorten positiivista mielikuvaa yrittäjyydestä, lisätään tietoja sekä taitoja yrittäjyydestä sekä vahvistetaan yrittäjämäisiä ominaisuuksia koulutussektorilla sekä koulujen ulkopuolisissa hankkeissa. Tutkimuskysymysten avulla pyrittiin selvittämään, miten yrittäjyyskasvatuksen tavoitteet näkyivät mentorointiprosessissa sekä mitkä tekijät luovat onnistuneen mentorointiprosessin Kesäyrittäjä-kampanjassa vuonna 2020. Kampanjan toteutuksesta vastasi valtakunnallisesti Talous ja nuoret (TAT) ja paikallisesti toimintaa organisoivat eri kaupungit, esimerkiksi Oulussa toteuttajana toimi BusinessOulu-liikelaitos. Tutkimuksen empiirinen osuuden aineisto kerättiin kyselylomakehaastattelulla, joka kerättiin vuonna 2020 kampanjassa toimineilta mentoreilta (N=7). Aineiston analyysi toteutettiin teorialähtöisellä sisällönanalyysilla, jossa teoreettisena viitekehyksenä toimi mentoritoiminta yrittäjyyskasvatuksen muotona. Analyysin osa-alueita olivat kasvatuskäsitteen neljä periaatetta: interaktio, intentionaalisuus, interaktion asymmetria sekä itsenäisen toiminnan vaatimus ja näiden lisäksi yrittäjyyskasvatusta tarkasteltiin kokonaisuutena. Tutkimuksessa havaittiin, että mentoreiden käsitykset yrittäjyydestä sekä yrittäjyyskasvatuksesta olivat keskenään erilaisia. Kesäyrittäjä-kampanjan asettamat tavoitteet yrittäjyyskasvatuksen osalta näyttäytyi mentoreiden näkemyksissä osittain jäsentymättöminä, eikä suurin osa mentoreista ollut asettanut yrittäjyyskasvatukseen liittyviä tavoitteita mentorointikerroille. Mentorit kokivat tavoitteiden asettamisen haasteelliseksi. Onnistuneen mentorointiprosessin keskeisiksi tekijöiksi havaittiin aineiston perusteella olevan luottamus, turvallisuus, sitoutuminen sekä henkilökemioiden toimivuus. Suurin osa mentoreista näki mentoroinnin symmetrisenä vuorovaikutussuhteena. Tämän lisäksi suurin osa mentoreista pyrki tukemaan yrittäjien itsenäistä toimintaa. Tutkimuksen tulosten perusteella mentoritoimintaa voidaan ymmärtää paremmin, jonka avulla mentoritoimintaa voidaan kehittää vaikuttavammaksi

Reply to 'Letter to Editor by Finsterer J and Zarrouk-Mahjoub S : Phenotypic manifestations of the m.8969G > A variant'

Peer reviewe

Real-time and post-processed georeferencing for hyperpspectral drone remote sensing

The use of drones and photogrammetric technologies are increasing rapidly in different applications. Currently, drone processing workflow is in most cases based on sequential image acquisition and post-processing, but there are great interests towards real-time solutions. Fast and reliable real-time drone data processing can benefit, for instance, environmental monitoring tasks in precision agriculture and in forest. Recent developments in miniaturized and low-cost inertial measurement systems and GNSS sensors, and Real-time kinematic (RTK) position data are offering new perspectives for the comprehensive remote sensing applications. The combination of these sensors and light-weight and low-cost multi- or hyperspectral frame sensors in drones provides the opportunity of creating near real-time or real-time remote sensing data of target object. We have developed a system with direct georeferencing onboard drone to be used combined with hyperspectral frame cameras in real-time remote sensing applications. The objective of this study is to evaluate the real-time georeferencing comparing with post-processing solutions. Experimental data sets were captured in agricultural and forested test sites using the system. The accuracy of onboard georeferencing data were better than 0.5 m. The results showed that the real-time remote sensing is promising and feasible in both test sites. © Authors 2018. CC BY 4.0 License.Peer reviewe

Cost-effectiveness of whole-exome sequencing in progressive neurological disorders of children

Objectives: To clarify the diagnostic utility and the cost-effectiveness of whole-exome sequencing (WES) as a routine early-diagnostic tool in children with progressive neurological disorders. Methods: Patients with infantile-onset severe neurological diseases or childhood-onset progressive neurological disorders were prospectively recruited to this WES study, in the pediatric neurology clinic at Helsinki University Hospital during 2016-2018. A total of 48 patients underwent a singleton WES. A control group of 49 children underwent traditional diagnostic examinations and were retrospectively collected from the hospital records. Their use of health care services, related to the diagnostic process, was gathered. Incremental cost-effectiveness ratio (ICER) per additional diagnosis was calculated from the health care provider perspective. Bootstrapping methods were used to estimate the uncertainty of cost-effectiveness outcomes. Results: WES provided a better diagnostic yield (38%) than diagnostic pathway that did not prioritize WES in early diagnosis (25%). WES outperformed other diagnostic paths especially when made early, within one year of first admission (44%). Cost-effectiveness in our results are conservative, affected by WES costs during 2016-18. Conclusions: WES is an efficient and cost-effective diagnostic tool that should be prioritized in early diagnostic path of children with progressive neurological disorders. The progressively decreasing price of the test improves cost-effectiveness further. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of European Paediatric Neurology Society.Peer reviewe

Mitochondrial dysfunction triggers actin polymerization necessary for rapid glycolytic activation

Publisher Copyright: © 2022 Chakrabarti et al.Mitochondrial damage represents a dramatic change in cellular homeostasis. One rapid response is perimitochondrial actin polymerization, termed acute damage-induced actin (ADA). The consequences of ADA are not understood. In this study, we show evidence suggesting that ADA is linked to rapid glycolytic activation upon mitochondrial damage in multiple cells, including mouse embryonic fibroblasts and effector CD8+ T lymphocytes. ADA-inducing treatments include CCCP, antimycin, rotenone, oligomycin, and hypoxia. The Arp2/3 complex inhibitor CK666 or the mitochondrial sodium–calcium exchanger (NCLX) inhibitor CGP37157 inhibits both ADA and the glycolytic increase within 5 min, supporting ADA’s role in glycolytic stimulation. Two situations causing chronic reductions in mitochondrial ATP production, mitochondrial DNA depletion and mutation to the NDUFS4 subunit of complex 1 of the electron transport chain, cause persistent perimitochondrial actin filaments similar to ADA. CK666 treatment causes rapid mitochondrial actin loss and a drop in ATP in NDUFS4 knock-out cells. We propose that ADA is necessary for rapid glycolytic activation upon mitochondrial impairment, to re-establish ATP production.Peer reviewe

Augmenting Immersive Telepresence Experience with a Virtual Body

We propose augmenting immersive telepresence by adding a virtual body, representing the user's own arm motions, as realized through a head-mounted display and a 360-degree camera. Previous research has shown the effectiveness of having a virtual body in simulated environments; however, research on whether seeing one's own virtual arms increases presence or preference for the user in an immersive telepresence setup is limited. We conducted a study where a host introduced a research lab while participants wore a head-mounted display which allowed them to be telepresent at the host's physical location via a 360-degree camera, either with or without a virtual body. We first conducted a pilot study of 20 participants, followed by a pre-registered 62 participant confirmatory study. Whereas the pilot study showed greater presence and preference when the virtual body was present, the confirmatory study failed to replicate these results, with only behavioral measures suggesting an increase in presence. After analyzing the qualitative data and modeling interactions, we suspect that the quality and style of the virtual arms, and the contrast between animation and video, led to individual differences in reactions to the virtual body which subsequently moderated feelings of presence.Comment: Accepted for publication in Transactions in Visualization and Computer Graphics (TVCG), to be presented in IEEE VR 202

Isolation of dental stem cell-enriched populations from continuously growing mouse incisors

Continuous growth of the rodent incisor is enabled by epithelial and mesenchymal stem cells (ESCs and MSCs) which unceasingly replenish enamel and dentin, respectively, that wear by persistent animal gnawing. Lineage tracing studies have provided evidence that ESCs contribute to all epithelial lineages of the tooth in vivo. Meanwhile, in the mouse incisor, MSCs continuously contribute to odontoblast lineage and tooth growth. However, in vitro manipulation of ESCs has shown little progress, mainly due to lack of appropriate protocol to successfully isolate, culture, expand, and differentiate ESCs in vitro without using the co-culture system. In this chapter we describe the isolation of the Sox2-GFP+ cell population that is highly enriched in ESCs. Isolated cells can be used for various types of analyses, including in vitro culture, single cell-related analyses, etc. Furthermore, we describe ways to obtain populations enriched in the incisor MSCs using FACS sorting of antibody-labeled cells. Easily accessible FACS sorting enables easy and relatively fast isolation of the cells labeled by the fluorescent protein. © Springer Science+Business Media, LLC, part of Springer Nature 2019.Peer reviewe