Harvestmen (Arachnida, Opiliones) in mixed and pure stands of spruce and beech - a study in the Solling mountains

Im Solling (Süd-Niedersachsen, Deutschland) wurden in einer Blockdesign-Studie 18 alte (> 90 Jahre) und mittelalte (58 - 89 Jahre) Fichten-, Misch- (Fichte/Buche) und Buchenbestände untersucht, die in sechs Blöcken angeordnet waren; jeder Block bestand aus einem Fichten-, einem Misch- und einem Buchenbestand. Es sollte überprüft werden, welchen Einfluss der Bestandestyp auf die Diversität und die Struktur von Populationen der epigäischen Bodenmakrofauna hat. In jeder Altersstufe wurde die Fauna über ein Jahr mit Streu- und Bodenproben, Bodenphotoeklektoren und Bodenfallen erfasst; die in diesem Beitrag dargelegten Ergebnisse zu den Weberknechten beziehen sich überwiegend auf Bodenfallenfänge. In beiden Altersstufen waren die Individuendichten der Arten und die Artendichte sowie der Deckungsgrad und die Diversität der Krautschicht in den lichteren Fichten- oder Fichten- und Mischbeständen signifikant am höchsten (nach einer nichtparametrischen zweifaktoriellen Varianzanalyse). Wichtige extrinsische Faktoren, die Diversität und Struktur der Weberknechtgemeinschaften beeinflussen, sind die Habitatdiversität, die Stratifikation der Vegetation und der für Populationen verfügbare Aktivitätsraum. In der vorliegenden Studie wird außerdem über die Phänologie der Weberknechtarten informiert. Im Solling wurden bisher 16 Weberknechtarten nachgewiesen.In the Solling mountains (Southern Lower Saxony, Germany) a block design study was carried out in 18 old (> 90 yrs) and middle-aged (58 - 89 yrs) spruce, beech, and mixed forest stands (spruce/ beech), arranged in six blocks, each consisting of a spruce, a beech, and a mixed forest stand, to investigate the effect of the forest stand type on the diversity and structure of epigeic macrofauna communities. In each age class, the fauna was sampled for one year by means of soil core samples, ground photo eclectors, and pitfall traps. The results for the harvestmen presented in this contribution focus on pitfall trap catches. In each age class, the numbers of individuals of the harvestmen species and the species density as well as the cover and diversity of the ground vegetation were significantly highest in the more open spruce or spruce and mixed forest stands, according to a nonparametrical twofactorial analysis of variance. Important extrinsic factors influencing the diversity and structure of the harvestmen communities are habitat diversity, stratification of the vegetation, and space for locomotory activity. Additionally, in the present study information about the phenology of the harvestmen species is given. In the Solling mountains 16 harvestmen species have been recorded to date

Long‑term demise of sub‑Antarctic glaciers modulated by the Southern Hemisphere Westerlies

The accelerated melting of ice on the Antarctic Peninsula and islands in the sub-Antarctic suggests that the cryosphere is edging towards an irreversible tipping point. How unusual is this trend of ice loss within the frame of natural variability, and to what extent can it be explained by underlying climate dynamics? Here, we present new high-resolution reconstructions of long-term changes in the extents of three glaciers on the island of South Georgia (54°S, 36°W), combining detailed analyses of glacial-derived sediments deposited in distal glacier-fed lakes and cosmogenic exposure dating of moraines. We document that the glaciers of South Georgia have gradually retracted since the Antarctic cold reversal (ACR, 14.5–12.8 ka), culminating in the disappearance of at least one of the reconstructed glaciers. The glacier retreat pattern observed in South Georgia suggests a persistent link to summer insolation at 55°S, which intensified during the period from the ACR to approximately 2 ka. It also reveals multi-decadal to centennial climate shifts superimposed on this long-term trend that have resulted in at least nine glacier readvances during the last 10.5 ka. Accompanying meridional changes in the Southern Hemisphere westerlies and their interconnection with local topography may explain these glacier readvances.publishedVersio

Maximum sustainable yield from interacting fish stocks in an uncertain world: two policy choices and underlying trade-offs

The case of fisheries management illustrates how the inherent structural instability of ecosystems can have deep-running policy implications. We contrast ten types of management plans to achieve maximum sustainable yields (MSY) from multiple stocks and compare their effectiveness based on a management strategy evaluation (MSE) that uses complex food webs in its operating model. Plans that target specific stock sizes ($B_{\text{MSY}}$) consistently led to higher yields than plans targeting specific fishing pressures ($F_{\text{MSY}}$). A new self-optimising control rule, introduced here for its robustness to structural instability, led to intermediate yields. Most plans outperformed single-species management plans with pressure targets set without considering multispecies interactions. However, more refined plans to "maximise the yield from each stock separately", in the sense of a Nash equilibrium, produced total yields comparable to plans aiming to maximise total harvested biomass, and were more robust to structural instability. Our analyses highlight trade-offs between yields, amenability to negotiations, pressures on biodiversity, and continuity with current approaches in the European context. Based on these results, we recommend directions for developments of EU fisheries policy.Comment: 21 pages, 1 figure, 2 tables, plus supplementary material (substantial textual revision of v5

Istraživanje nečiste i čiste (100) površine vanadija STM-om

Scanning tunneling microscopy is used to characterize different states of the V(100) surface during the cleaning procedure in an ultrahigh vacuum apparatus, starting with the "as received" sample and finishing with an almost perfectly clean surface. We show, for the first time, STM images of the clean V(100) surface and with atomic resolution.Primijenili smo skenirajući tunelirajući mikroskop (STM) za topografsku karakterizaciju površine V(100) prije i tijekom čišćenja u aparaturi za ultravisok vakuum, počevši s “dobivenim” uzorkom i nakon pojedinih postupaka čišćenja. Po prvi puta se pokazuju slike potpuno čiste površine V(100) s atomskim razlučivanjem, snimljene STM-om

Concomitant statin use does not impair the clinical outcome of patients with diffuse large B cell lymphoma treated with rituximab-CHOP

Preclinical data indicated a detrimental effect of statins on the anti-lymphoma activity of rituximab. We evaluated the impact of concomitant statin medication on the response and survival of patients with diffuse large B cell lymphoma (DLBCL) receiving rituximab-cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP) as first-line therapy. Medical histories of patients with DLBCL who were treated with R-CHOP as first-line therapy were assessed for concomitant statin use, response after completion of chemotherapy, event-free survival (EFS), and overall survival (OS). Furthermore, 2-[18F]fluor-2-deoxyglucose (FDG)-PET/CT results after completion of first-line therapy were compared between the groups. Overall, 145 patients with DLBCL treated with R-CHOP from January 2001 to December 2009 were analyzed. Twenty-one (15%) patients received statins throughout therapy. Five-year EFS was 67.3% in patients without statins compared with 79% in patients receiving statins during R-CHOP (HR, 0.47; 95% CI, 0.15-1.54, p = 0.2). Five-year OS was 81.4% for patients without statins compared with 93.3% for patients taking statins (HR, 0.58; 95% CI 0.07-4.55, p = 0.6). There were no statistically significant differences in the rates of complete remissions between the two groups (75% in the non-statin group versus 86% in the statin group, p = 0.45). A trend toward a lower rate of complete metabolic responses in FDG-PET/CT after chemotherapy was seen in patients without statin medication compared with the patients taking statins (84% versus 92%, p = 0.068). Concomitant statin use had no adverse impact on response to chemotherapy, EFS, and OS in patients treated with R-CHOP for DLBC

Brain state stability during working memory is explained by network control theory, modulated by dopamine D1/D2 receptor function, and diminished in schizophrenia

Dynamical brain state transitions are critical for flexible working memory but the network mechanisms are incompletely understood. Here, we show that working memory entails brainwide switching between activity states. The stability of states relates to dopamine D1 receptor gene expression while state transitions are influenced by D2 receptor expression and pharmacological modulation. Schizophrenia patients show altered network control properties, including a more diverse energy landscape and decreased stability of working memory representations

Chiral and deconfinement transition from correlation functions: SU(2) vs. SU(3)

We study a gauge invariant order parameter for deconfinement and the chiral condensate in SU(2) and SU(3) Yang-Mills theory in the vicinity of the deconfinement phase transition using the Landau gauge quark and gluon propagators. We determine the gluon propagator from lattice calculations and the quark propagator from its Dyson-Schwinger equation, using the gluon propagator as input. The critical temperature and a deconfinement order parameter are extracted from the gluon propagator and from the dependency of the quark propagator on the temporal boundary conditions. The chiral transition is determined using the quark condensate as order parameter. We investigate whether and how a difference in the chiral and deconfinement transition between SU(2) and SU(3) is manifest.Comment: 15 pages, 9 figures. For clarification one paragraph and two references added in the introduction and two sentences at the end of the first and last paragraph of the summary. Appeared in EPJ

Prospective evaluation of quality of life effects in patients undergoing palliative radiotherapy for brain metastases

Background: Recently published results of quality of life (QoL) studies indicated different outcomes of palliative radiotherapy for brain metastases. This prospective multi-center QoL study of patients with brain metastases was designed to investigate which QoL domains improve or worsen after palliative radiotherapy and which might provide prognostic information. Methods: From 01/2007-01/2009, n=151 patients with previously untreated brain metastases were recruited at 14 centers in Germany and Austria. Most patients (82 %) received whole-brain radiotherapy. QoL was measured with the EORTC-QLQ-C15-PAL and brain module BN20 before the start of radiotherapy and after 3 months. Results: At 3 months, 88/142 (62 %) survived. Nine patients were not able to be followed up. 62 patients (70.5 % of 3-month survivors) completed the second set of questionnaires. Three months after the start of radiotherapy QoL deteriorated significantly in the areas of global QoL, physical function, fatigue, nausea, pain, appetite loss, hair loss, drowsiness, motor dysfunction, communication deficit and weakness of legs. Although the use of corticosteroid at 3 months could be reduced compared to pre-treatment (63 % vs. 37 %), the score for headaches remained stable. Initial QoL at the start of treatment was better in those alive than in those deceased at 3 months, significantly for physical function, motor dysfunction and the symptom scales fatigue, pain, appetite loss and weakness of legs. In a multivariate model, lower Karnofsky performance score, higher age and higher pain ratings before radiotherapy were prognostic of 3-month survival. Conclusions: Moderate deterioration in several QoL domains was predominantly observed three months after start of palliative radiotherapy for brain metastases. Future studies will need to address the individual subjective benefit or burden from such treatment. Baseline QoL scores before palliative radiotherapy for brain metastases may contain prognostic information