Quantitative cw Overhauser DNP Analysis of Hydration Dynamics

Liquid state Overhauser Effect Dynamic Nuclear Polarization (ODNP) has experienced a recent resurgence of interest. In particular, a new manifestation of the ODNP measurement measures the translational mobility of water within 5-10 \AA\ of an ESR-active spin probe (i.e. the local translational diffusivity D_{local} near an electron spin resonance active molecule). Such spin probes, typically stable nitroxide radicals, have been attached to the surface or interior of macromolecules, including proteins, polymers, and membrane vesicles. Despite the unique specificity of this measurement, it requires only a standard X-band (~10 GHz) continuous wave (cw) electron spin resonance (ESR) spectrometer, coupled with a standard nuclear magnetic resonance (NMR) spectrometer. Here, we present a set of developments and corrections that allow us to improve the accuracy of quantitative ODNP and apply it to samples more than two orders of magnitude lower than were previously feasible.Comment: 25 page manuscript submitted to PNMR

ACTIVE AND PASSIVE REMOTE SENSING FOR ATMOSPHERIC APPLICATIONS

The atmosphere surrounding our planet is vital for the existence of many living organisms, including humans. Although this layer is quite thin, there are numerous components interacting with each other with processes taking place across widely different spatial and temporal scales. No single instrument is able to cover all of these scales, and therefore, in order to advance our knowledge of atmospheric processes and composition, different instruments, methods and synergy of instruments have to be applied. Remote sensing techniques offer a variety of possibilities for atmospheric research. Satellite remote sensing is exploited to get a regional or global view on the problems, to verify climate models, as well as to reach locations which are not accessible for measurements otherwise. Ground-based remote sensing allows a continuous monitoring of the vertical structure of the atmosphere and, due to exploiting various wavelengths, the observation of atmospheric compounds of various sizes from gases to aerosol particles to snowflakes. In this thesis, several remote sensing techniques have been utilized to find new methods of utilizing existing observations as well as the application of known methods to new geographical locations. A novel method is proposed for retrieving convective boundary layer height during spring and summer months using insect echoes in radar returns. Observations from several different radar frequencies were analysed and the proposed method was proven applicable at all frequencies given some limitations. Moreover, this method can serve as a platform for future research in different geographical locations where insects might behave differently. The synergy of ground-based lidar and airborne in situ measurements were used to study elevated aerosol layers in Southern Finland. Based on two cases, a clear-sky and partly cloudy case, the temporal and spatial variability of aerosol particle number concentration in the boundary layer and several elevated layers were investigated. Nucleation mode particles (the smallest aerosol sizes) were also detected in one of the elevated layers, which was probably not mixing with the boundary layer during a new particle formation event. In addition to aerosol particles, some lidars have the capability to measure water vapor profiles. Several calibration methods for this type of lidar were analysed in order to find an alternative to the usual method of using a radiosonde launched close by, since radiosondes may not always be available at every site. Output from a weather forecast model, or a radiosonde profile which was 100 km away, were both found to be reliable, whereas the use of satellite products required more caution in the absence of other methods. The seasonal variability of water vapour profiles was also studied. Satellite remote sensing observations were probed to obtain proxies of nucleation mode aerosol particles, which are otherwise not seen from space. So far, the results were not very successful, however, some bottlenecks were identified with a potential to improve the proxies in the future.Atmosfären som omger vår planet är avgörande för existensen av olika levande organismer, inklusive människor. Trots att detta lager är ganska tunt, finns det massor av komponenter som interagerar med varandra och processer som äger rum i olika rumsliga och tidsmässiga skalor. Inget enskilt instrument kan täcka alla dessa skalor och därför måste olika instrument, metoder och synergier av instrument användas för att föra fram vår kunskap om atmosfäriska processer och sammansättningar. Fjärranalysmetoder erbjuder en mängd olika möjligheter för atmosfärisk forskning. Satellitfjärranalys utnyttjas för att få en regional eller global syn på problemen, för att verifiera klimatmodeller, samt för att nå platser som annars inte är tillgängliga för mätningar. Markbaserad fjärranalys möjliggör en kontinuerlig övervakning av atmosfärens vertikala struktur och, genom att utnyttja olika våglängder, observation av atmosfäriska sammansättningar av olika storlekar från aerosolpartiklar till snöflingor. I denna avhandling har flera fjärranalysmetoder använts för att hitta nya sätt att utnyttja befintliga observationer samt för att tillämpa kända metoder på nya geografiska platser. En ny metod föreslås för att skapa en konvektiv gränsskiktshöjd under vår- och sommarmånaderna med hjälp av insektsekon i radarsignalen. Observationer från flera olika radarfrekvenser analyserades och den föreslagna metoden visade sig vara tillämpbar på alla frekvenser med vissa begränsningar. Dessutom kan denna metod fungera som en plattform för framtida forskning på olika geografiska platser där insekter kan bete sig annorlunda. Synergin mellan markbaserad lidar och luftburna in situ-mätningar användes för att studera förhöjda aerosollager i södra Finland. Den temporala och rumsliga variationen av aerosolpartikelkoncentrationen i gränsskiktet och förhöjda lager undersöktes baserat på två fall, ett med klar himmel och ett delvis molnigt. Nukleationsmodpartiklar (de minsta aerosolstorlekarna) detekterades också i ett av de förhöjda skikten, som troligtvis inte blandades med gränsskiktet under en ny partikelbildningshändelse. Förutom aerosolpartiklar har vissa lidarer förmågan att mäta vattenångsprofiler. Flera kalibreringsmetoder för denna typ av lidar analyserades för att hitta ett alternativ till den vanliga metoden att använda en radiosonde som lanseras i närheten, eftersom radiosonder inte alltid är tillgängliga på alla platser. Utdata från en väderprognosmodell eller en radiosondeprofil på 100 km avstånd, visade sig båda vara tillförlitliga, medan användningen av satellitprodukter krävde mer försiktighet i avsaknad av andra metoder. Den säsongsmässiga variationen av vattenångprofiler studerades också. Satellitfjärranalysobservationer undersöktes för att erhålla proxies för aerosolpartiklar i kärnbildningsläge, vilka annars inte kan ses från rymden. Hittills har resultaten dock inte varit särskilt framgångsrika, men vissa flaskhalsar har identifierats med potential att förbättra fullmakterna i framtiden

Food Sharing Initiatives and Food Democracy: Practice and Policy in Three European Cities

Calls for greater food democracy in Europe have emerged as the limitations of urban food systems dominated by commercial organisations are documented, but little attention has been paid to how policy arrangements affect attempts to transition to more democratic food futures. This article examines food sharing initiatives - increasingly facilitated by the use of information and communication technologies - as a potential means to enhance urban food democracy, and explores the role of policy in shaping those practices in three European capital cities: Berlin, London, and Dublin. We pose two related questions: To what extent are diverse food sharing initiatives exemplars of food democracy, and to what extent do policy arrangements affect food sharing practices and the nature of any food democracy they might embody? Our empirical evidence demonstrates where the goals and impacts of food sharing initiatives align with key dimensions of food democracy. We also consider how food sharing initiatives - and any food democracy dimensions that they support - are affected by the policy environment in which they operate. The food sharing initiatives examined revealed to be agents of pro-democratic change, at least within the boundaries of their spheres of influence, despite policies rarely having their activities and aspirations in mind

Feasability of a Frameless Brain Biopsy System for Companion Animals Using Cone-Beam CT-Based Automated Registration.

The aim of the present study was to evaluate the use of a novel intraoperative cone-beam computed tomography (CBCT)-based automated registration system for frameless stereotactic brain biopsy in companion animals. An experimental cadaveric study evaluated thalamic and piriform lobe target site needle placement error in three dogs and three cats without a history of intracranial disease. Diagnostic accuracy and diagnostic yield were prospectively evaluated in twenty-four client-owned dogs and four cats with intracranial disease. Twenty-one procedures were performed post mortem (eighteen dogs and three cats), and seven biopsy procedures were performed in alive patients (six dogs and one cat). Procedural duration was evaluated in ten post mortem and four living patients. Outcome was evaluated in six dogs and one cat. In dogs, the calculated median needle placement error was 1.8 mm (range 0.71-2.84 mm) and 1.53 mm (range 1.45-1.99 mm) for piriform lobe and thalamus target sites, respectively. In cats, the calculated median needle placement error was 0.79 mm (range 0.6-1.91 mm) for the piriform lobe target site and 1.29 mm (range 0.47-2.69 mm) for the thalamic target site. The diagnostic yield was 96.4% (95% CI 0.81-0.99), the diagnostic accuracy was 94.4% (95% CI 0.72-0.99). Median total procedural duration for post mortem biopsies was 57.5 min (range 41-69 min). Median total procedural duration for intra vitam biopsies was 122.5 min (range 103-136 min). Three dogs were discharged 1 day after biopsy and one dog after 6 days. Two dogs and one cat were euthanized 24 and 48 h after biopsy. Intraoperative CBCT-based automated image registration for frameless stereotactic biopsies in companion animals is capable of providing diagnostic brain biopsy specimens independent of skull size and morphology with diagnostic yield and accuracy comparable to published values for diverse frameless and frame-based stereotaxy systems used in veterinary medicine. Duration of the procedure is not negatively affected and within the published range with other systems. Mobile intraoperative CBCT-based registration combined with neuronavigation delivers diagnostic brain biopsies in companion animals

Are the “100 of the world’s worst” invasive species also the costliest?

Biological invasions are increasing worldwide, damaging ecosystems and socioeconomic sectors. Two decades ago, the “100 of the world’s worst” invasive alien species list was established by the IUCN to improve communications , identifying particularly damaging ‘flagship’ invaders globally (hereafter, worst). Whilst this list has bolstered invader awareness, whether worst species are especially economically damaging and how they compare to other invaders (hereafter, other) remain unknown. Here, we quantify invasion costs using the most comprehensive global database compiling them (InvaCost). We compare these costs between worst and other species against sectorial, taxonomic and regional descriptors, and examine temporal cost trends. Only 60 of the 100 worst species had invasion costs considered as highly reliable and actually observed estimates (median: US$43 million). On average, these costs were significantly higher than the 463 other invasive species recorded in InvaCost (median: US$ 0.53 million), although some other species had higher costs than most worst species. Damages to the environment from the worst species dominated, whereas other species largely impacted agriculture. Disproportionately highest worst species costs were incurred in North America, whilst costs were more evenly distributed for other species; animal invasions were always costliest. Proportional management expenditures were low for the other species, and surprisingly, over twice as low for the worst species. Temporally, costs increased more for the worst than other taxa; however, management spending has remained very low for both groups. Nonetheless, since 40 species had no robust and/or reported costs, the “true” cost of “some of the world’s worst” 100 invasive species still remains unknown

Two mycoheterotrophic orchids from Thailand tropical dipterocarpacean forests associate with a broad diversity of ectomycorrhizal fungi

<p>Abstract</p> <p>Background</p> <p>Mycoheterotrophic plants are considered to associate very specifically with fungi. Mycoheterotrophic orchids are mostly associated with ectomycorrhizal fungi in temperate regions, or with saprobes or parasites in tropical regions. Although most mycoheterotrophic orchids occur in the tropics, few studies have been devoted to them, and the main conclusions about their specificity have hitherto been drawn from their association with ectomycorrhizal fungi in temperate regions.</p> <p>Results</p> <p>We investigated three Asiatic Neottieae species from ectomycorrhizal forests in Thailand. We found that all were associated with ectomycorrhizal fungi, such as Thelephoraceae, Russulaceae and Sebacinales. Based on ¹³C enrichment of their biomass, they probably received their organic carbon from these fungi, as do mycoheterotrophic Neottieae from temperate regions. Moreover, ¹³C enrichment suggested that some nearby green orchids received part of their carbon from fungi too. Nevertheless, two of the three orchids presented a unique feature for mycoheterotrophic plants: they were not specifically associated with a narrow clade of fungi. Some orchid individuals were even associated with up to nine different fungi.</p> <p>Conclusion</p> <p>Our results demonstrate that some green and mycoheterotrophic orchids in tropical regions can receive carbon from ectomycorrhizal fungi, and thus from trees. Our results reveal the absence of specificity in two mycoheterotrophic orchid-fungus associations in tropical regions, in contrast to most previous studies of mycoheterotrophic plants, which have been mainly focused on temperate orchids.</p

Santo-Pietro-di-Tenda – Monte Revincu

Le complexe mégalithique du Monte Revincu a été signalé par A. de Mortillet dès 1893, mais son étude n’avait pas été réactualisée. L’ensemble est situé à l’ouest du golfe de Saint-Florent. La densité et la diversité des monuments dans cette microrégion, à la limite du Nebbio et des Agriate permet une bonne approche de l’ensemble des questions d’analyse spatiale. L’occupation préhistorique de la région est essentiellement constituée par des sépultures mégalithiques et des statues-menhirs. Les ..

Santo-Pietro-di-Tenda – Monte Revincu

Le complexe mégalithique du Monte Revincu a été signalé par A. de Mortillet dès 1893, mais son étude n’avait pas été réactualisée. L’ensemble est situé à l’ouest du golfe de Saint-Florent. La densité et la diversité des monuments dans cette microrégion, à la limite du Nebbio et des Agriate permet une bonne approche de l’ensemble des questions d’analyse spatiale. L’occupation préhistorique de la région est essentiellement constituée par des sépultures mégalithiques et des statues-menhirs. Les ..