272 research outputs found

    Solar System Objects in the ISOPHOT 170 micron Serendipity Survey

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    The ISOPHOT Serendipity Survey (ISOSS) covered approximately 15 % of the sky at a wavelength of 170 micron while the ISO satellite was slewing from one target to the next. By chance ISOSS slews went over many solar system objects (SSOs). We identified the comets, asteroids and planets in the slews through a fast and effective search procedure based on N-body ephemeris and flux estimates. The detections were analysed from a calibration and scientific point of view. Through the measurements of the well-known asteroids Ceres, Pallas, Juno and Vesta and the planets Uranus and Neptune it was possible to improve the photometric calibration of ISOSS and to extend it to higher flux regimes. We were also able to establish calibration schemes for the important slew end data. For the other asteroids we derived radiometric diameters and albedos through a recent thermophysical model. The scientific results are discussed in the context of our current knowledge of size, shape and albedos, derived from IRAS observations, occultation measurements and lightcurve inversion techniques. In all cases where IRAS observations were available we confirm the derived diameters and albedos. For the five asteroids without IRAS detections only one was clearly detected and the radiometric results agreed with sizes given by occultation and HST observations. Four different comets have clearly been detected at 170 micron and two have marginal detections. The observational results are presented to be used by thermal comet models in the future. The nine ISOSS slews over Hale-Bopp revealed extended and asymmetric structures related to the dust tail. We attribute the enhanced emission in post-perihelion observations to large particles around the nucleus. The signal patterns are indicative of a concentration of the particles in trail direction.Comment: 15 pages, 6 figures, 6 tables; Accepted for publication in Astronomy and Astrophysic

    The impacts of environmental warming on Odonata: a review

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    Climate change brings with it unprecedented rates of increase in environmental temperature, which will have major consequences for the earth's flora and fauna. The Odonata represent a taxon that has many strong links to this abiotic factor due to its tropical evolutionary history and adaptations to temperate climates. Temperature is known to affect odonate physiology including life-history traits such as developmental rate, phenology and seasonal regulation as well as immune function and the production of pigment for thermoregulation. A range of behaviours are likely to be affected which will, in turn, influence other parts of the aquatic ecosystem, primarily through trophic interactions. Temperature may influence changes in geographical distributions, through a shifting of species' fundamental niches, changes in the distribution of suitable habitat and variation in the dispersal ability of species. Finally, such a rapid change in the environment results in a strong selective pressure towards adaptation to cope and the inevitable loss of some populations and, potentially, species. Where data are lacking for odonates, studies on other invertebrate groups will be considered. Finally, directions for research are suggested, particularly laboratory studies that investigate underlying causes of climate-driven macroecological patterns

    Unanticipated population structure of European grayling in its northern distribution: implications for conservation prioritization

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    <p>Abstract</p> <p>Background</p> <p>The European grayling (<it>Thymallus thymallus</it>) is a salmonid fish native to Europe, with a distribution ranging from England and France to the Ural Mountains of north-western Russia. The majority of grayling populations inhabit freshwater rivers and lakes but some populations also occupy brackish water in northern parts of the Baltic Sea. Previous population genetic studies have demonstrated that grayling populations in Finland, Estonia and Russia belong to a single mitochondrial lineage and exhibit high levels of differentiation even at a small geographic scale. As a result, we predicted that grayling populations should not cluster regionally. Despite the extensive amount of genetic research that has been carried out on grayling, comprehensive national-level information on population structure of grayling in Northern Europe is still lacking. Yet this is the level at which populations are currently managed.</p> <p>Results</p> <p>We found unanticipated population structure of grayling clustering into three groups largely corresponding to the northern, Baltic and south-eastern geographic areas of Finland using 13 microsatellite loci. We also found a high level of genetic differentiation among the groups and moderate to high differentiation within the groups. This combined with low variability strongly indicates that genetic drift and limited migration have a major impact on grayling population structure. An allele size permutation test indicated that mutations at microsatellite loci have not significantly contributed to genetic differentiation among the three Finnish groups. However, at the European scale, mutations had significantly contributed to population differentiation.</p> <p>Conclusion</p> <p>This research provides novel genetic information on European grayling in its northern distribution range and has clear implications for supporting country-scale conservation efforts. Specifically, the strong between population divergence observed indicates that single populations should generally be recognized as separate management units. We also introduced an alternative prioritization strategy for population conservation based on the evaluation of the relative roles of different evolutionary forces shaping the gene pools. We envision that the proposed approach to categorize populations for conservation will be a useful tool for wildlife researchers and conservationists working on a diverse range of organisms.</p

    Component analysis of nutritionally rich chloroplasts: recovery from conventional and unconventional green plant species

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    A study of the literature indicates that chloroplasts synthesise a range of molecules, many of which have nutritional value for humans, but as yet no one has established the nutritional credentials of chloroplasts recovered from plant cells. Chloroplast-rich-fractions (CRFs) were prepared from green plant species and the macro- and micronutrient composition compared with the whole leaf materials (WLMs). The results indicated that, on a dry weight basis, CRF material from a range of green biomass was enriched in lipids and proteins, and in a range of micronutrients compared with the WLM. Vitamins E, pro-vitamin A, and lutein were all greater in CRF preparations. Of the minerals, iron was most notably concentrated in CRF. Spinach CRFs possessed the highest α-tocopherol (62 mg 100 g-1 , dry weight (DW)), β-carotene (336 mg 100 g- 1 DW) and lutein (341 mg 100 g-1 DW) contents, whilst grass CRFs had the highest concentration of alpha-linolenic acid (ALA) (69.5 mg g-1). The higher concentrations of α-tocopherol, β-carotene, lutein, ALA and trace minerals (Fe and Mn) in CRFs suggest their potential use as concentrated ingredients in food formulations deficient in these nutrients

    Effects of multiple targeted repelling measures on the behaviour of individually tracked birds in an area of increasing human–wildlife conflict

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    1. Some animal populations are rapidly increasing in numbers and expanding their ranges, leading to intensified human–wildlife conflicts. A wide range of tools has been developed to repel animals from areas where they are suspected to cause damage. For waterfowl, direct comparisons of multiple repelling methods have so far focused only on species´ presence, total numbers, cost effectiveness or subsequent damage assessments, but not on individual behaviour. 2. Here, we investigated the individual responses of free-flying geese to three repelling methods using high-resolution tracking data. In an experimental setup, tracked individuals were repelled by human approach, gunshot sound or handheld lasers. 3. We found that repelling success and return time to the field where the repelling took place increased when individuals were repelled multiple times. Travel distances after the repelling events were longer after human approach and gunshot sound compared to the handheld laser treatments. In spring, the probability to return to the same field was higher after repelling with handheld lasers, but no difference between treatments was evident in autumn. We observed no increase in the probability to visit accommodation fields, where geese were allowed to forage and were not repelled, after the repelling events. 4. Synthesis and applications. We found no strong differences between the three methods regarding the repelling effectiveness and the resulting behaviour of the tracked geese. However, the higher return rates of individuals after repelling with handheld lasers in spring suggest that this method might be less effective in situations with bright sunlight or very large aggregations of geese. Apart from these limitations, we can recommend handheld lasers for repelling as they might reduce energetic losses for the geese and disturbance of non-target wildlife. Since repelling by gunshot sound and handheld lasers was twice as fast as repelling by human approach, those methods will reduce working hours by 50% and therefore be more cost-effective in practice

    Effects of multiple targeted repelling measures on the behaviour of individually tracked birds in an area of increasing human-wildlife conflict

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    1. Some animal populations are rapidly increasing in numbers and expanding their ranges, leading to intensified human-wildlife conflicts. A wide range of tools has been developed to repel animals from areas where they are suspected to cause damage. For waterfowl, direct comparisons of multiple repelling methods have so far focused only on species ' presence, total numbers, cost effectiveness or subsequent damage assessments, but not on individual behaviour. 2. Here, we investigated the individual responses of free-flying geese to three repelling methods using high-resolution tracking data. In an experimental setup, tracked individuals were repelled by human approach, gunshot sound or handheld lasers. 3. We found that repelling success and return time to the field where the repelling took place increased when individuals were repelled multiple times. Travel distances after the repelling events were longer after human approach and gunshot sound compared to the handheld laser treatments. In spring, the probability to return to the same field was higher after repelling with handheld lasers, but no difference between treatments was evident in autumn. We observed no increase in the probability to visit accommodation fields, where geese were allowed to forage and were not repelled, after the repelling events. 4. Synthesis and applications. We found no strong differences between the three methods regarding the repelling effectiveness and the resulting behaviour of the tracked geese. However, the higher return rates of individuals after repelling with handheld lasers in spring suggest that this method might be less effective in situations with bright sunlight or very large aggregations of geese. Apart from these limitations, we can recommend handheld lasers for repelling as they might reduce energetic losses for the geese and disturbance of non-target wildlife. Since repelling by gunshot sound and handheld lasers was twice as fast as repelling by human approach, those methods will reduce working hours by 50% and therefore be more cost-effective in practice.</p

    Heinäveden reitillä merkittyjen taimenten ja järvilohien vaellukset, kasvu ja pyynti vuosina 2009–2022

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    Taimenen ja järvilohen vaellusten pituutta ja suuntaa, pyyntikokoa, kasvua ja pyyntimenetelmiä selvitettiin pyydystämällä vesistöistä 501 taimenta ja 30 järvilohta ja merkitsemällä ne t-ankkurimerkeillä Heinäveden reitillä Vuoksen päävesistöalueella vuosina 2009–2019. Kalat pyydystettiin merkintään virtavesiltä vapavälineillä ja verkolla ja järviltä vapavälineillä. Taimenten merkintäpituuden keskiarvo ja vaihteluväli olivat 40 ja 15–79 cm ja järvilohen vastaavasti 54 ja 20–88 cm. Taimenista arviolta 50–90 % oli luonnossa syntyneitä, järvilohista mahdollisesti muutama. Lisäksi Heinäveden koskiin istutettiin 1821 ankkurimerkittyä 2-vuotiasta taimenta vuosina 2012–2017 ja Kermajärvelle 727 ankkurimerkittyä 2-vuotiasta järvilohta vuonna 2012. Tulokset perustuvat vapaa-ajankalastajilta saatuihin merkkipalautuksiin ja -havaintoihin. Virtavesillä merkityistä 487 taimenesta saatiin 66 palautusta merkintävirtavesiltä ennen kalojen mahdollista järvivaellusta, 16 palautusta järviltä, 7 palautusta toisesta koskesta järven toiselta puolelta ylä- tai alavirrasta sekä 8 palautusta merkintäkoskista mahdollisesti järvivaelluksen tehneinä. Järvillä merkityt 14 taimenta tuottivat 4 palautusta järviltä ja 1 palautuksen koskilta. Merkityistä istukkaista saapui vain 14 palautusta. Järvilohista saatiin 6 palautusta järviltä ja 1 palautus koskilta. Virtavesillä merkittyjen ja järviltä pyydettyjen taimenien lähtöpituuden vaihteluväli oli ainakin 29–77, mutta mahdollisesti 21–86 cm. Virtavesillä merkittyjen taimenten pyyntipituuden keskiarvo ja vaihteluväli olivat 53 ja 29–86 cm, järvillä merkittyjen taimenten 56 ja 50–70 cm, merkittyjen taimenistukkaiden 42 ja 23–69 cm, järvillä ja virtavesillä merkittyjen järvilohien 54 ja 45–73 cm sekä merkittyjen järvilohi-istukkai-den 53 ja 40–76 cm. Virtavesillä merkittyjen taimenten merkinnän ja pyynnin välinen pituuskasvu ja ajanjakso olivat keskimäärin 8 cm ja 415 vrk. Pituuskasvu ja ajanjakso olivat keskimäärin sitä pienempiä mitä suurempana kala oli merkitty. Pituuskasvun keskiarvo oli vain 6 ja 3 cm merkintäpituusluokissa 40–56,9 cm ja ≥57 cm. Koskista järvivaellukselle lähteneistä taimenista saatiin 11 palautusta ylävirran ja 12 palautusta alavirran puoleisilta järviltä. Vaellusmatka merkintäkosken niskalta tai alareunalta pyyntipaikalle suorinta vesireittiä pitkin oli keskimäärin 19 kilometriä. Pisimmät vaellukset olivat 139 km ylävirtaan ja 56 km alavirtaan. Taimenen kaikkien merkintäryhmien merkkipalautuksissa saaliksi otetuista kaloista pyydystettiin verkolla ja vavalla 87 ja 13 %. Järvilohella vastaavat osuudet olivat toisinpäin, 27 ja 73 %. Järviltä saatujen merkkipalautusten perusteella villin järvitaimenen ja järvilohen elinkierron toteutuminen järvivaelluksella oli todennäköisesti niukkaa tutkimusjaksolla Heinäveden reitillä ja Vuoksen päävesistön läntisessä osassa. Kalastuskuolevuus järvillä oli todennäköisesti suuri lajien elinkiertoon suhteutettuna

    Arctic migrating barnacle geese utilize accommodation fields in a new agricultural staging area

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    The recovery of threatened species after conservation measures can lead to human–wildlife conflicts. One example of such is the recent population growth of the Barnacle Goose Branta leucopsis, a large herbivorous bird. During migration, geese stage in large numbers on agricultural fields in range countries and cause substantial damage to farms. A combination of repelling fields, where geese were chased off by humans, and accommodation fields, which provide refuge sites for foraging geese, has been suggested as an effective management tool to mitigate conflicts.Using high-resolution satellite tracking data, we investigated habitat selection of 41 barnacle geese staging in Northern Karelia, Finland, during spring 2021. We estimated relative habitat use by these geese and conducted a fine-scale analysis of their use of different fields by employing Hidden Markov Models and integrated step-selection analysis. Fields included normal crop (no goose management), project and other (private and Nature 2000 area) accommodation fields and repelling fields. Project accommodation and repelling fields were established on areas known to have a long history of high grazing pressure by barnacle geese.We found that behavioural data of geese can be categorized into three different states (static, slow and fast movement). Static and slow states were used for local field selection, fast state for field selection in the regional area, and all states for field selection after leaving a repelling field.Overall, relative habitat use indicated that geese utilize accommodation fields more than expected by their availability. Integrated step-selection analyses revealed that geese avoided normal and repelling versus project accommodation fields at the regional scale. At the local scale, they preferred project accommodation fields over all other fields. After leaving a repelling field, geese did not show preference for any accommodation over repelling fields.Synthesis and application. Geese show individual selection for accommodation fields compared to normal or repelling fields across several scales. Our results suggest that the accommodation field concept—consisting of refuge areas and no-go areas where geese are repelled from—can help to mitigate the human–wildlife conflict using local stakeholders' knowledge.202

    Microfluidic analysis techniques for safety assessment of pharmaceutical nano- and microsystems

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    This chapter reviews the evolution of microfabrication methods and materials, applicable to manufacturing of micro total analysis systems (or lab‐on‐a‐chip), from a general perspective. It discusses the possibilities and limitations associated with microfluidic cell culturing, or so called organ‐on‐a‐chip technology, together with selected examples of their exploitation to characterization of pharmaceutical nano‐ and microsystems. Materials selection plays a pivotal role in terms of ensuring the cell adhesion and viability as well as defining the prevailing culture conditions inside the microfluidic channels. The chapter focuses on the hepatic safety assessment of nanoparticles and gives an overview of the development of microfluidic immobilized enzyme reactors that could facilitate examination of the hepatic effects of nanomedicines under physiologically relevant conditions. It also provides an overview of the future prospects regarding system‐level integration possibilities facilitated by microfabrication of miniaturized separation and sample preparation systems as integral parts of microfluidic in vitro models.Non peer reviewe
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