The Forum of European Geological Surveys Geochemistry Task Group 1994-1996 inventory

The Forum of European Geological Surveys (FOREGS) includes representatives from 33 European countries and is responsible for co-ordinating Geological Survey activities in Europe. The FOREGS Geochemistry Task Group was established in 1994 to develop a strategy for the preparation of European geochemical maps following the recommendations of the International Geological Correlation Programme (IGCP) Project 259 ‘International Geochemical Mapping’ (now the International Union of Geological Sciences (IUGS) /International Association of Geochemistry and Cosmochemistry (IAGC) Working Group on Global Geochemical Baselines). The FOREGS geochemistry programme is aimed at preparing a standardised European geochemical baseline to IGCP-259 standards. The principal aims of this dataset will be for environmental purposes, as a baseline for the assessment of the extent and distribution of contaminated land in the context of variations in the natural geochemical background, but it will also have applications in resource assessment and for the development of policy for the sustainable management of metalliferous mineral and other resources. The first phase of the programme was the compilation of an inventory of geochemical data based on the results of a questionnaire completed by Geological Surveys and related organisations throughout the FOREGS community. The results show that the sample types which have been used most extensively are stream sediment (26% coverage), surface water (19% coverage) and soil (11% coverage). Stream sediments have been collected using a narrow range of mesh sizes (< 150–< 200 μm), but soil samples have been collected according to two different conventions: some surveys used a similar mesh size range to that used for stream sediments while others employed the < 1000 or < 2000 μm fractions traditionally used by soil surveys. Sample densities range from 1 sample per 0.5 km2 to 1 per 3500 km2. Various analytical methods have been used, but most of the available data have been calibrated using international reference materials, and data for the most important of the potentially harmful elements (PHEs) are available for most datasets. Systematic radiometric data are available for only a small proportion of Europe, a situation which compares very unfavourably with that in Australia, North America, the former Soviet Union and many developing countries. Recommendations are made for increasing the compatibility of geochemical methods between national geochemical surveys as a basis for the preparation of a series of European geochemical maps. The next stage of the FOREGS Geochemistry Task Group will be the collection of the Global Reference Network of samples against which to standardise national datasets according to the methods recommended in the final report of the IGCP 259 programme

Roughness and multiscaling of planar crack fronts

We consider numerically the roughness of a planar crack front within the long-range elastic string model, with a tunable disorder correlation length $\xi$. The problem is shown to have two important length scales, $\xi$ and the Larkin length $L_c$. Multiscaling of the crack front is observed for scales below $\xi$, provided that the disorder is strong enough. The asymptotic scaling with a roughness exponent $\zeta \approx 0.39$ is recovered for scales larger than both $\xi$ and $L_c$. If $L_c > \xi$, these regimes are separated by a third regime characterized by the Larkin exponent $\zeta_L \approx 0.5$. We discuss the experimental implications of our results.Comment: 8 pages, two figure

Dopamine D_2-receptor activation elicits akinesia, rigidity, catalepsy, and tremor in mice expressing hypersensitive 4 nicotinic receptors via a cholinergic-dependent mechanism

Recent studies suggest that high-affinity neuronal nicotinic acetylcholine receptors (nAChRs) containing α4 and β2 subunits (α4β2*) functionally interact with G-protein-coupled dopamine (DA) D_2 receptors in basal ganglia. We hypothesized that if a functional interaction between these receptors exists, then mice expressing an M2 point mutation (Leu9'Ala) rendering 4 nAChRs hypersensitive to ACh may exhibit altered sensitivity to a D_2-receptor agonist. When challenged with the D_(2)R agonist, quinpirole (0.5–10 mg/kg), Leu9'Ala mice, but not wild-type (WT) littermates, developed severe, reversible motor impairment characterized by rigidity, catalepsy, akinesia, and tremor. While striatal DA tissue content, baseline release, and quinpirole-induced DA depletion did not differ between Leu9'Ala and WT mice, quinpirole dramatically increased activity of cholinergic striatal interneurons only in mutant animals, as measured by increased c-Fos expression in choline acetyltransferase (ChAT)-positive interneurons. Highlighting the importance of the cholinergic system in this mouse model, inhibiting the effects of ACh by blocking muscarinic receptors, or by selectively activating hypersensitive nAChRs with nicotine, rescued motor symptoms. This novel mouse model mimics the imbalance between striatal DA/ACh function associated with severe motor impairment in disorders such as Parkinson’s disease, and the data suggest that a D_(2)R–α4*-nAChR functional interaction regulates cholinergic interneuron activity.—Zhao-Shea, R., Cohen, B. N., Just, H., McClure-Begley, T., Whiteaker, P., Grady, S. R., Salminen, O., Gardner, P. D., Lester, H. A., Tapper, A. R. Dopamine D2-receptor activation elicits akinesia, rigidity, catalepsy, and tremor in mice expressing hypersensitive α4 nicotinic receptors via a cholinergic-dependent mechanism

Anterior cruciate ligament reconstruction with bone-patellar tendon-bone autograft versus allograft in young patients

Objectives: Traditionally, bone-patella tendon-bone (BTB) autograft has been the gold standard graft choice for younger, athletic patients requiring ACL reconstruction. However, donor site morbidity, post-operative patella fracture, and increased operative time have led many surgeons to choose BTB allograft for their reconstructions. Opponents of allografts feel that slower healing time, higher rate of graft failure, and potential for disease transmission makes them undesirable graft choices in athletic patients. The purpose of this study is to evaluate the clinical outcomes, both subjective and objective, of young patients that who have undergone either BTB autograft or allograft reconstructions with a minimum of 2-year follow-up. Methods: One hundred and twenty patients (60 autograft, 60 allograft), age 25 and below at time of surgery, were contacted after being retrospectively identified as patients having an ACL reconstruction with either a BTB allograft or autograft by one senior surgeon. Patients were administered the Lysholm Knee Scoring Scale and IKDC Subjective Knee Evaluation questionnaires. Fifty (25 BTB autograft and 25 BTB allograft) of the 120 returned for physical examination as well as completion of a single leg hop test and laxity evaluation using a KT-1000 arthrometer evaluation. Of the 120 patients contacted, there were a total of 7 failures (5.8%) requiring revision, 6 in the allograft group (86%) and 1 in the autograft group (14%). Results: The average Lysholm scores were 89.0 and 89.56 and the average IKDC scores were 90.8 and 92.1 in the autograft and allograft groups respectively. The differences in the Lysholm scores and the IKDC scores were not significant. The single leg hop and KT-1000 scores were also not significantly different. One autograft patient had a minor motion deficit. Three allograft patients had a grade 1 Lachman and pivot glide. One autograft patient and two allograft patients had mild patellafemoral crepitus. There was no significant difference in anterior knee pain between the two groups Conclusion: There is no significant difference in patient-rated outcome between ACL reconstructions using BTB autografts versus allografts. However, the overall study group did reveal an increased failure rate requiring revision in the allograft group. © The Author(s) 2015

Toiminnallisen kytkennällisyyden mittarit aivosähkökäyristä anestesian aikana

Tiivistelmä. Toiminnallisen kytkennällisyyden mittaaminen perustuu aivojen eri osista mitattujen signaalien tai tapahtumien tilastolliseen riippuvuuteen toisistaan. Aivosähkökäyriä saadaan aikaan mittaamalla aivosolujen toimiessaan tuottamien sähköisten potentiaalien muutoksia ajan suhteen eri puolilta aivoja. Aivosähkökäyriä kutsutaan myös elektroenkefalogrammiksi. Niitä voidaan helposti mitata aivojen ulkopuolelta ihon pinnalta. Toiminnallista kytkennällisyyttä voidaan mitata muun muassa aivosähkökäyristä. Anestesia on tila, jossa kohde ei pysty havaitsemaan tai tuntemaan mitään. Usein se saadaan aikaan jonkin aineen avulla hallitusti. Anestesia on siis hallittu tapa saada aivot johonkin muuhun tilaan kuin missä ne ovat hereilläolon aikana. Anestesiaa käytetään hyvin yleisesti potilaan saattamiseksi tiedottomaan tilaan lääketieteellisten toimenpiteiden aikana. Tämän kirjallisuuskatsauksen tarkoituksena on tutkia, minkälaisia menetelmiä tällä hetkellä käytetään toiminnallisen kytkennällisyyden mittaamiseksi aivosähkökäyristä anestesian aikana. Anestesian avulla tapahtuva aivojen hallittu siirtäminen tilasta toiseen mahdollistaa aivojen toiminnan vertailun eri tiloissa, mikä on olennaista toiminnallisen kytkennällisyyden tutkimiseksi. Näin ollen kyseinen yhdistelmä on kiinnostava tutkimuskohde. Lähdeaineistona on käytetty varsin laajaa julkaistujen tutkimusten joukkoa työn aiheeseen liittyen. Katsauksessa esitellään ensin taustatietoa aiheen ymmärtämiseksi ja sitten syvennytään varsin laajaan ja kirjavaan joukkoon menetelmiä. Tutkimusten perusteella tavoitteena on ymmärtää aivojen toimintaa eri tietoisuuden tiloissa. Käytännössä tätä ymmärrystä sovelletaan ainakin anestesian syvyyden mittarien kehittämisessä lääketieteellisiin tarkoituksiin leikkauspotilaan turvallisuuden ja toimenpiteestä toipumisen varmistamiseksi. Menetelmissä ollaan siirrytty kohtalaisen yksinkertaisista signaalien tilastollisen riippuvuuden tarkasteluun perustuvista menetelmistä epälineaarisiin menetelmiin, kytkennällisyyden monimuotoisuuden tarkasteluun ja toiminnallisten verkkojen rakenteen tarkasteluun.Functional connectivity measures from the EEG during anaesthesia. Abstract. Functional connectivity measures are based on the statistical dependence of signals or events measured from different parts of the brain. Electroencephalogram measures the temporal evolution of the electrical potentials, produced by the brain neurons, from different parts of the brain. Electroencephalogram can be easily measured from outside the brain, on top of the skin. Functional connectivity can be measured amongst others from that. Anaesthesia is a state in which the target is not able to observe or feel anything. Usually it is induced with some anaesthetic agent in a controlled manner. Anaesthesia is therefore a controlled way to get the brain to some other state from the state in which it is during wakefulness. Anaesthesia is commonly used to get the patient into an unconscious state during medical operations. The purpose of this literature review is to research what kind of methods are currently used to measure functional connectivity from electroencephalogram data during anaesthesia. The controlled transition of the brain from a state to another with anaesthesia makes it possible to compare the functionality of the brain in different states, which is vital for researching functional connectivity. Therefore this combination is an interesting target for research. A rather large group of research publications relating to the topic of this thesis has been used as the source material. The review first introduces some background information for understanding the topic and then concentrates on a rather large variety of methods. Based on the research, the purpose is to understand the workings of the brain in different states of consciousness. In practice this understanding is applied at least when developing measures of the depth of anaesthesia for medical purposes, to ensure the safety and proper recovery from the operation of a patient. The focus in the methods has been shifted from relatively simple methods based on observing the statistical dependency between signals to nonlinear methods, observing the diversity of connectivity, and observing the structure of functional networks

Aivosähkökäyriin perustuvien toiminnallisen kytkennällisyyden mittarien soveltuvuus sedaation syvyyden ilmaisemiseen

Tiivistelmä. Sedaatiolla tarkoitetaan anestesian eli keinotekoisen tiedottomuuteen vaivuttamisen kevyempää muotoa eli vähentyneen tietoisuuden tilaa. Anestesian ja sedaation syvyyden mahdollisimman tarkka ja luotettava ilmaiseminen lääketieteellisen toimenpiteen aikana on tärkeää, jotta potilas pysyisi koko toimenpiteen ajan oikeassa tilassa ja palautuisi toimenpiteestä mahdollisimman hyvin ja nopeasti. Anestesian syvyyttä pyritään ilmaisemaan aivosähkökäyristä mitattavan toiminnallisen kytkennällisyyden avulla. Toiminnallisen kytkennällisyyden mittareita on laaja joukko. Tässä tutkimuksessa vertaillaan kuuden mittarin soveltuvuutta sedaation syvyyden ilmaisemiseen. Mukana olevat mittarit jakautuvat kahteen luokkaan. Informaatioteoreettisia mittareita ovat normalisoitu symbolinen siirtoentropia, standardoitu permutaatioiden yhteinen informaatio ja vaihejättöentropia. Klassiseen signaalianalyysiin perustuvia mittareita ovat painotettu vaihejättöindeksi, vaihe-amplitudikytkentä ja amplitudien verhokäyrien korrelaatio. Tutkimuksessa käytetty aineisto pitää sisällään tiedon, että anesteettisen aineen määrä veressä ei aina korreloi tietoisuuden tilan kanssa. Normalisoitu symbolinen siirtoentropia ja amplitudien verhokäyrien korrelaatio ilmaisevat selkeästi anesteettisen aineen määrää veressä, mutta eivät kerro todellisesta tietoisuuden tilasta. Standardoitu permutaatioiden yhteinen informaatio ja etenkin painotettu vaihejättöentropia ilmaisevat varsin selkeästi todellista tietoisuuden tilaa sedaation aikana. Tulokset kertovat, että on mahdollista, että mittari, joka näyttäisi mittaavan keskimääräisen henkilön tietoisuuden tilaa hyvin, ei todellisuudessa erotakaan veressä olevan anesteettisen aineen määrää todellisesta tietoisuuden tilasta. Painotetun vaihejättöindeksin on kirjallisuudessa todettu ilmaisevan heikosti anestesian syvyyttä. Näin ollen tämän tutkimuksen tulokset kertovat, että anestesian syvyyden ilmaisemisessa heikosti toimiva mittari voikin ilmaista sedaation syvyyttä varsin hyvin.The applicability of functional connectivity measures based on electroencephalogram for indicating the depth of sedation. Abstract. Sedation means the state of reduced consciousness and is the lighter form of anaesthesia, that means artificially getting the target into the state of unconsciousness. Indicating the depth of anaesthesia and sedation as accurately and reliably as possible during a medical operation is important, so that the patient stays in the intended state during the whole operation and recovers from the operation as well and soon as possible. The endeavour is to indicate the depth of anaesthesia from the electroencephalogram with functional connectivity measures. There exists a large variety of functional connectivity measures. In this study, the applicability of six measures for indicating the depth of sedation is compared. The measures compared can be divided into two classes. Information theoretic measures are normalized symbolic transfer entropy, standardized permutation mutual information, and phase lag entropy. Measures based on classic signal analysis are weighted phase lag index, phase-amplitude coupling, and amplitude envelope correlation. The data set used in the study contains the information that the amount of anaesthetic agent in the blood does not always correlate with the state of consciousness. Normalized symbolic transfer entropy and amplitude envelope correlation indicate clearly the amount of anaesthetic agent in the blood, but do not indicate the actual state of consciousness. Standardized permutation mutual information and especially weighted phase lag index indicate quite clearly the actual state of consciousness during sedation. The results tell that it is possible that a measure that seems to measure the state of consciousness of an average person well, is not actually able to differentiate the amount of anaesthetic agent in the blood from the actual state of consciousness. Weighted phase lag index has been noticed in the literature to indicate poorly the depth of anaesthesia. Therefore, the results of this study tell, that a measure that indicates the depth of anaesthesia poorly might indicate the depth of sedation quite well

Binding of an oligomeric ellagitannin series to bovine serum albumin (BSA): analysis by isothermal titration calorimetry (ITC)

A unique series of oligomeric ellagitannins was used to study their interactions with bovine serum albumin (BSA) by isothermal titration calorimetry. Oligomeric ellagitannins, ranging from monomer to heptamer and a mixture of octamer–undecamers, were isolated as individual pure compounds. This series allowed studying the effects of oligomer size and other structural features. The monomeric to trimeric ellagitannins deviated most from the overall trends. The interactions of ellagitannin oligomers from tetramers to octa–undecamers with BSA revealed strong similarities. In contrast to the equilibrium binding constant, enthalpy showed an increasing trend from the dimer to larger oligomers. It is likely that first the macrocyclic part of the ellagitannin binds to the defined binding sites on the protein surface and then the “flexible tail” of the ellagitannin coats the protein surface. The results highlight the importance of molecular flexibility to maximize binding between the ellagitannin and protein surfaces

Structural Features of Condensed Tannins Influence Their Antimethanogenic Potential in Forage Plants

Despite years of research on the antimethanogenic potential of condensed tannins (CT), their large-scale application is inhibited by a substantial variability in previous studies with regards to their impact on ruminant nutrition. This variability mainly results from the complexity of CT structures, and their impact on methane emissions is often unaccounted for. Hence, this study (a) evaluated the variability in antimethanogenic potential across six forage species, (b) linked methane emissions to tannin activity, and (c) determined the impact of CT structural features on methane abatement. Six forage species were grown in a greenhouse under controlled environmental conditions, namely, sainfoin (Onobrychis viciifolia), birdsfoot trefoil (Lotus corniculatus), big trefoil (Lotus pedunculatus), plantain (Plantaga lanceolata), sulla (Hedysarum coronarium) and lucerne (Medicago sativa). The plants were harvested at the flowering stage and leaf samples were analysed for chemical composition, condensed tannin concentration and structural features, before being incubated in rumen fluid for 24 hours. Lucerne was used as negative control (without tannins) and an additional polyethylene glycol (PEG) treatment was included, to inactivate tannins and link any effect on fermentation characteristics to tannin activity only. A strong variability across the species (P\u3c 0.0001) was observed on methane emissions. Sulla had the highest antimethanogenic potential and decreased methane emissions by 47% compared to lucerne. All species rich in CTs decreased both methane and total gas production, yet the PEG treatment did not alter the methane proportion in the total gas produced. In addition to CT concentration (R= -0.78), methane emissions were found to be negatively correlated with the CT structural features, prodelphinidin percentage (R= -0.6) and mean degree of polymerisation (R= -0.57). This study demonstrated that antimethanogenic potential of forages depends on CT concentration as well as on structural features and incorporating them in the studies can efficiently assess their impact on ruminant nutrition