Developmental dynamics of a beech-dominated ‘natural forest’ – permanent observation site on limestone in the Hainich National Park, Thuringia

Heute besteht bei Geoökologen und Forstleuten weitgehend Konsens darüber, dass die Wälder Mitteleuropas vor dem massiven menschlichen Einwirken, also vor etwa 2-3.000 Jahren weitgehend buchendominiert waren (BÜCKING et al. 1994, ELLENBERG 1996). Ihre Flächen wurden zunächst durch Rodung drastisch verringert. Später führte vor allem Brennholznutzung dazu, ihren Anteil in den übriggebliebenen Wäldern weiter zu reduzieren. Schließlich tat die Aufforstung und Umwandlung mit Nadelbäumen ein Übriges, um ihre Bedeutung einzuschränken. So kam es, dass ihr Anteil von ehemals ca. 70 auf heute noch 15 % in Deutschland sank (BMVEL 2004). Die verbliebenen Buchenwälder sind zudem stark durch forstliche Bewirtschaftung überprägt.A long term study of the natural dynamics of a semi-natural beech forest largely untouched for fifty years began in 1999. A part of the >150 year old beech/ash stand was completely inventoried (28 ha), and the gaps in the forest canopy measured repeatedly. The gaps ranged from 8 – 592 m², with a mean size of less than 150 m². There were, on average, 3 gaps/ha, occupying less than 4 % of the stand area. The establishment and survival rates of admixed species were low under the largely intact canopy. The total seedling number was only slightly higher in the gaps (approx. 7 plants/m²) than under the canopy (approx. 6 plants/m²). The problem of seedling establishment was exacerbated by the unregulated influence of deer. Ash seedlings rarely exceeded heights of 50 cm without the protection of fencing, and the development of the sycamores was halted at 90 cm. Even the unpalatable beech benefited slightly from fencing. The average volume of coarse woody debris (CWD) was 62 m³/ha, comprised chiefly of large lying timber, but also of large standing dead wood. The findings to date support the assumption that beech forests left to develop naturally regenerate gradually by means of numerous small scale disturbances, and tend towards an ever greater dominance of beech

Comparison of four different programs for the analysis of hemispherical photographs using parameters of canopy structure and solar radiation transmittance

There have been many studies involving the use of hemispherical photographs to indirectly estimate canopy structures and forest light environments. A variety of commercial and free software packages are available for the analysis of hemispherical photographs. The costs of investment might represent an advantage of the free programmes over the commercial, but as yet little has been documented about the differences in their outputs and in the technical applications from a user (ecologist and forester) perspective. The objective of the study was to compare the canopy structure variables (canopy openness and effective plant area index) and solar radiation transmission estimates (direct, diffuse and global solar radiation transmittances) from digital hemispherical photographs taken under two forest canopy conditions (gap and closed canopy) in three different broadleaf forest regions (Chile, Germany, Venezuela) and calculated using four different programmes. The hemispherical photographs were analysed using one commercial (HemiView) and three free programmes (Gap Light Analyzer, hemIMAGE and Winphot). The results obtained revealed that all of the programmes computed similar estimates of both canopy structures and below-canopy solar radiation. Only the results relating to the effective plant area index with an ellipsoidal leaf angle distribution made with HemiView and Winphot deviated significantly. Other user aspects are also discussed, such as costs, image formats, computer system requirements, etc.In vielen Studien werden Hemisphärenphotos genutzt um indirekt die Kronenstruktur und die Belichtungsverhältnisse zu schätzen. Verschiedene kommerzielle und kostenfreie Softwarepakete sind zu Analyse von Hemisphärenphotos verfügbar. Es gibt bisher keine umfassende Vergleichsstudie zu Ergebnissen oder technischer Handhabung aus Sicht der Nutzer dieser Programme (Ökologen und Forstwissenschaftler). Das Ziel dieser Studie war der Vergleich der Schätzungen von Kronenstrukturvariablen (Kronenöffnung und effektiver Pflanzenflächenindex) Solartransmission (direkte, diffuse und Global-Strahlung) aus digitalen Hemisphärenphotos berechnet mit vier verschiedenen Programmen (kostenpflichtig: Hemi- View und frei: Gap Light Analyzer, hemIMAGE and Winphot). Die verwendeten Photos stammen aus drei verschiedenen Laubwaldregionen (Chile, Deutschland und Venezuela) und repräsentieren jeweils Verhältnisse unter geschlossenem Kronendach und in Lücken. Die ermittelten Schätzungen für die verschiedenen Strukturvariablen und Einstrahlungsverhältnisse zeigten eine sehr hohe Übereinstimmung. Einzig der effektive Pflanzenflächenindex basierend auf ellipsoider Blattwinkelverteilung unterschied sich signifikant zwischen den Programmen. Weitere für Nutzer interessante Aspekte wie Kosten, Bildformate, Systemvoraussetzungen und mehr wurden verglichen und diskutiert

Wellbeing and coping strategies of alcohol and other drug therapeutic community workers: a qualitative study

Purpose The purpose of this paper is to examine the strategies utilised to facilitate the wellbeing of workers of an alcohol and other drug (AOD) therapeutic community (TC). Design/methodology/approach This paper reports on the findings of a qualitative study that involved in-depth interviews with 11 workers from an AOD TC organisation in Australia that provides both a residential TC program and outreach programs. Interviews were analysed using thematic analysis. Findings Three main interconnected themes emerged through analysis of the data: 1) The challenges of working in an AOD TC organisation, including vicarious trauma, the isolation and safety for outreach workers, and a lack of connection between teams; 2) Individual strategies for coping and facilitating wellbeing, such as family, friend and partner support, and self-care practices; 3) Organisational facilitators of worker wellbeing, including staff supervision, employment conditions and the ability to communicate openly about stress. The analysis also revealed cross-cutting themes including the unique challenges and wellbeing support needs of outreach and lived experience workers. Research limitations/implications Rather than just preventing burnout, AOD TC organisations can also play a role in facilitating worker wellbeing. Practical implications This paper discusses a number of practical suggestions and suggests that additional strategies targeted at ‘at risk’ teams or groups of workers may be needed alongside organisation-wide strategies. Originality/value This paper provides a novel and in-depth analysis of strategies to facilitate TC worker wellbeing and has implications for TC staff, managers and researchers

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS

Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations

Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at s√=8 TeV with the ATLAS detector

The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy s√=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fb−1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (ΛR c) of approximately 30

Measurement of χ c1 and χ c2 production with s√ = 7 TeV pp collisions at ATLAS

The prompt and non-prompt production cross-sections for the χ c1 and χ c2 charmonium states are measured in pp collisions at s√ = 7 TeV with the ATLAS detector at the LHC using 4.5 fb−1 of integrated luminosity. The χ c states are reconstructed through the radiative decay χ c → J/ψγ (with J/ψ → μ + μ −) where photons are reconstructed from γ → e + e − conversions. The production rate of the χ c2 state relative to the χ c1 state is measured for prompt and non-prompt χ c as a function of J/ψ transverse momentum. The prompt χ c cross-sections are combined with existing measurements of prompt J/ψ production to derive the fraction of prompt J/ψ produced in feed-down from χ c decays. The fractions of χ c1 and χ c2 produced in b-hadron decays are also measured

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector

Results of a search for H → τ τ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fb−1 and 20.3 fb−1 at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ → `νν¯ with ` = e, µ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of µ = 1.43 +0.43 −0.37 is consistent with the predicted Yukawa coupling strength in the Standard Model

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector

This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}$and correspond to an integrated luminosity of$4.6\;{\rm f}{{{\rm b}}^{-1}}$. The measurement is performed by reconstructing the boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet centre-of-mass frame is used to suppress the large multi-jet background. The cross-section for events with a hadronically decaying W or Z boson, with transverse momentum${{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}$and pseudorapidity$|\eta |\lt 1.9$, is measured to be${{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques