838 resultados para Defensive drivers.


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Ahead of the World Cup in Brazil the crucial question for the Swiss national coach is the nomination of the starting eleven central back pair. A fuzzy set Qualitative Comparative Analysis assesses the defensive performances of different Swiss central back pairs during the World Cup campaign (2011 – 2014). This analysis advises Ottmar Hitzfeld to nominate Steve von Bergen and Johan Djourou as the starting eleven central back pair. The alternative with a substantially weaker empirical validity would be Johan Djourou together with Phillippe Senderos. Furthermore, this paper aims to be a step forward in mainstream football analytics. It analyses the undervalued and understudied defense (Anderson and Sally 2012, Statsbomb 2013) by explaining collective defensive performances instead of assessments of individual player or team performances. However, a qualitatively (better defensive metrics) and quantitatively (more games) improved and extended data set would allow for a more sophisticated analysis of collective defensive performances.

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Animal pollination is essential for the reproductive success of many wild and crop plants. Loss and isolation of (semi-)natural habitats in agricultural landscapes can cause declines of plants and pollinators and endanger pollination services.We investigated the independent effects of these drivers on pollination of young cherry trees in a landscape-scale experiment. We included (i) isolation of study trees from other cherry trees (up to 350 m), (ii) the amount of cherry trees in the landscape, (iii) the isolation from other woody habitats (up to 200 m) and (iv) the amount of woody habitats providing nesting and floral resources for pollinators. At the local scale, we considered effects of (v) cherry flower density and (vi) heterospecific flower density. Pollinators visited flowers more often in landscapes with high amount of woody habitat and at sites with lower isolation from the next cherry tree. Fruit set was reduced by isolation from the next cherry tree and by a high local density of heterospecific flowers but did not directly depend on pollinator visitation. These results reveal the importance of considering the plant’s need for con-specific pollen and its pollen competition with co-flowering species rather than focusing only on pollinators’ habitat requirements and flower visita-tion. It proved to be important to disentangle habitat isolation from habitat loss, local from landscape-scale effects, and direct effects of pollen availability on fruit set from indirect effects via pollinator visitation to understand the delivery of an agriculturally important ecosystem service.

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The automotive industry is confronted with increasing competition, leading to higher cost pressures and the demand to optimize production processes and value chains. Here the RFID technology promises to improve a range of processes in logistics and manufacturing. Despite its promising potential in the automotive industry, RFID has not yet made a decisive step from pilots to real-life implementations in the supply chain. Building on existing models of technology adoption, we analyze RFID adoption dynamics in the automotive industry. Building on existing IOS adoption models tailored to RFID specifics and based on ten semi-structured interviews with OEMs and suppliers, we evaluate main drivers of RFID adoption in the automotive industry. Our key findings are that the use of a coercive approach by the OEM could be redundant because of the market-driven RFID adoption among many suppliers. Furthermore, suppliers implementing RFID can now gain an early mover competitive advantage by developing higher trust in their relationship with the OEM as well as accumulating unique expertise in this area.

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Disentangling biotic and abiotic drivers of wild mushroom fruiting is fraught with difficulties because mycelial growth is hidden belowground, symbiotic and saprotrophic supply strategies may interact, and myco-ecological observations are often either discontinuous or too short. Here, we compiled and analyzed 115 417 weekly fungal fruit body counts from permanent Swiss inventories between 1975 and 2006. Mushroom fruiting exhibited an average autumnal delay of 12 days after 1991 compared with before, the annual number of fruit bodies increased from 1801 to 5414 and the mean species richness doubled from 10 to 20. Intra- and interannual coherency of symbiotic and saprotrophic mushroom fruiting, together with little agreement between mycorrhizal yield and tree growth suggests direct climate controls on fruit body formation of both nutritional modes. Our results contradict a previously reported declining of mushroom harvests and propose rethinking the conceptual role of symbiotic pathways in fungi-host interaction. Moreover, this conceptual advancement may foster new cross-disciplinary research avenues, and stimulate questions about possible amplifications of the global carbon cycle, as enhanced fungal production in moist mid-latitude forests rises carbon cycling and thus increases greenhouse gas exchanges between terrestrial ecosystems and the atmosphere.

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One of the central goals of neuroscience research is to determine how networks of neurons control and modify behavior. One of the most influential model systems for this kind of analysis is the siphon and gill withdrawal reflex of the marine mollusc A. californica. In response to tactile stimulation, the siphon displays 3 different responses: (1) a posterior pointing and leveling (flaring) of the siphon in response to tail stimulation (the siphon T response), (2) constriction and anterior pointing to head stimulation (the siphon H response) and (3) constriction and withdrawal between the animal's parapodia (the siphon S response). The siphon S response is pseudoconditioned by a noxious tail stimulus to resemble the siphon T response. Behavioral and combined behavioral/intracellular studies were conducted to determine the motor neuronal control of these behaviors and to search for mechanisms of siphon response transformation following pseudoconditioning. The present studies have found that the flaring component of pseudoconditioned siphon S responses occurs during mantle pumping (MP) triggered by noxious tail stimulation. Siphon stimulation also triggers MP, as recorded in neurons of the Interneuron II pattern generator which commands MP. The 4 LF$\rm\sb{SB}$ siphon motor neurons (SMNs) were found necessary and sufficient for the siphon T response, while SMNs RD$\rm\sb S$ and LD$\rm\sb{S1}$ were found necessary and sufficient for the siphon H response. Following pseudoconditioning, there is an increase in the number of evoked spikes to the test stimulus for the LF$\rm\sb{SB}$ cells and a decreased number for RD$\rm\sb S.$ Siphon flaring occurring during the pseudoconditioned response correlates with increased LF$\rm\sb{SB}$ activity during triggered MP cycles. This suggests that psuedoconditioning is in part due to reconfiguration of the motor outputs of the Interneuron II network. These results suggest that these defensive responses are controlled and patterned by a well-defined, finite set of motor neurons and interneurons (Interneuron II) that are dedicated to specific behavioral functions, but also have parallel distributed properties. ^

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Climate affects the timing, rate and dynamics of tree growth, over time scales ranging from seconds to centuries. Monitoring how a tree's stem radius varies over these time scales can provide insight into intra-annual stem dynamics and improve our understanding of climate impacts on tree physiology and growth processes. Here, we quantify the response of radial conifer stem size to environmental fluctuations via a novel assessment of tree circadian cycles. We analyze four years of sub-hourly data collected from 56 larch and spruce trees growing along a natural temperature gradient of ∼6 °C in the central Swiss Alps. During the growing season, tree stem diameters were greatest at mid-morning and smallest in the late evening, reflecting the daily cycle of water uptake and loss. Along the gradient, amplitudes calculated from the stem radius cycle were ∼50% smaller at the upper site (∼2200 m a.s.l.) relative to the lower site (∼800 m a.s.l.). We show changes in precipitation, temperature and cloud cover have a substantial effect on typical growing season diurnal cycles; amplitudes were nine times smaller on rainy days (>10 mm), and daily amplitudes are approximately 40% larger when the mean daily temperature is 15–20 °C than when it is 5–10 °C. We find that over the growing season in the sub-alpine forests, spruce show greater daily stem water movement than larch. However, under projected future warming, larch could experience up to 50% greater stem water use, which may severely affect future growth on already dry sites. Our data further indicate that because of the confounding influences of radial growth and short-term water dynamics on stem size, conventional methodology probably overstates the effect of water-linked meteorological variables (i.e. precipitation and relative humidity) on intra-annual tree growth. We suggest future studies use intra-seasonal measurements of cell development and consider whether climatic factors produce reversible changes in stem diameter. These study design elements may help researchers more accurately quantify and attribute changes in forest productivity in response to future warming.

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Sensitization is a simple form of learning which refers to an enhancement of a behavioral response resulting from an exposure to a novel stimulus. While sensitization is found throughout the animal world, little is known regarding the underlying neural mechanisms. By taking advantage of the simple nervous system of the marine mollusc Aplysia, I have begun to examine the cellular and molecular mechanisms underlying this simple form of learning. In an attempt to determine the generality of the mechanisms of neuromodulation underlying sensitization, I have investigated and compared the modulation of neurons involved in two defensive behaviors in Aplysia, the defensive inking response and defensive tail withdrawal.^ The motor neurons that produce the defensive release of ink receive a slow decreased conductance excitatory postsynaptic potential (EPSP) in response to sensitizing stimuli. Using electrophysiological techniques, it was found that serotonin (5-HT) mimicked the physiologically produced slow EPSP. 5-HT produced its response through a reduction in a voltage-independent conductance to K('+). The 5-HT sensitive K('+) conductance of the ink motor neurons was separate from the fast K('+), delayed K('+), and Ca('2+)-activated K('+) conductances found in these and other molluscan neurons. 5-HT was shown to produce a decrease in K('+) conductance in the ink motor neurons through an elevation of cellular cAMP.^ The mechanosensory neurons that participate in the defensive tail withdrawal response are also modulated by sensitizing stimuli through the action of 5-HT. Using electrophysiological techniques, it was found that 5-HT modulated the tail sensory neurons through a reduction in a voltage-dependent conductance to K('+). The serotonin-sensitive K('+) conductance was found to be largely a Ca('2+)-activated K('+) conductance. Much like the ink motor neurons, 5-HT produced its modulation through an elevation of cellular cAMP. While the actual K('+) conductance modulated by 5-HT in these two classes of neurons differs, the following generalizations can be made: (1) the effects of sensitizing stimuli are mimicked by 5-HT, (2) 5-HT produces its effect through an elevation of cellular cAMP, and (3) the conductance to K('+) is modulated by 5-HT. ^

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Climate change mitigation policy is driven by scientific knowledge and involves actors from the international, national and local decision-making levels. This multi-level and cross-sectoral context requires collaborative management when designing mitigation solutions over time and space. But collaboration in general policymaking settings, and particularly in the complex domain of climate mitigation, is not an easy task. This paper addresses the question of what drives collaboration among collective actors involved in climate mitigation policy. We wish to investigate whether common beliefs or power structures influence collaboration among actors. We adopt a longitudinal approach to grasp differences between the early and more advanced stages of mitigation policy design. We use survey data to investigate actors’ collaboration, beliefs and power, and apply a Stochastic Actor-oriented Model for network dynamics to three subsequent networks in Swiss climate policy between 1995 and 2012. Results show that common beliefs among actors, as well as formal power structures, have a higher impact on collaboration relations than perceived power structures. Furthermore, those effects hold true for decision-making about initial mitigation strategies, but less so for the implementation of those measures.

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Mountain vegetation is strongly affected by temperature and is expected to shift upwards with climate change. Dynamic vegetation models are often used to assess the impact of climate on vegetation and model output can be compared with paleobotanical data as a reality check. Recent paleoecological studies have revealed regional variation in the upward shift of timberlines in the Northern and Central European Alps in response to rapid warming at the Younger Dryas/Preboreal transition ca. 11700years ago, probably caused by a climatic gradient across the Alps. This contrasts with previous studies that successfully simulated the early Holocene afforestation in the (warmer) Central Alps with a chironomid-inferred temperature reconstruction from the (colder) Northern Alps. We use LandClim, a dynamic landscape vegetation model to simulate mountain forests under different temperature, soil and precipitation scenarios around Iffigsee (2065m a.s.l.) a lake in the Northwestern Swiss Alps, and compare the model output with the paleobotanical records. The model clearly overestimates the upward shift of timberline in a climate scenario that applies chironomid-inferred July-temperature anomalies to all months. However, forest establishment at 9800 cal. BP at Iffigsee is successfully simulated with lower moisture availability and monthly temperatures corrected for stronger seasonality during the early Holocene. The model-data comparison reveals a contraction in the realized niche of Abies alba due to the prominent role of anthropogenic disturbance after ca. 5000 cal. BP, which has important implications for species distribution models (SDMs) that rely on equilibrium with climate and niche stability. Under future climate projections, LandClim indicates a rapid upward shift of mountain vegetation belts by ca. 500m and treeline positions of ca. 2500m a.s.l. by the end of this century. Resulting biodiversity losses in the alpine vegetation belt might be mitigated with low-impact pastoralism to preserve species-rich alpine meadows.

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Modeling of future water systems at the regional scale is a difficult task due to the complexity of current structures (multiple competing water uses, multiple actors, formal and informal rules) both temporally and spatially. Representing this complexity in the modeling process is a challenge that can be addressed by an interdisciplinary and holistic approach. The assessment of the water system of the Crans-Montana-Sierre area (Switzerland) and its evolution until 2050 were tackled by combining glaciological, hydrogeological, and hydrological measurements and modeling with the evaluation of water use through documentary, statistical and interview-based analyses. Four visions of future regional development were co-produced with a group of stakeholders and were then used as a basis for estimating future water demand. The comparison of the available water resource and the water demand at monthly time scale allowed us to conclude that for the four scenarios socioeconomic factors will impact on the future water systems more than climatic factors. An analysis of the sustainability of the current and future water systems based on four visions of regional development allowed us to identify those scenarios that will be more sustainable and that should be adopted by the decision-makers. The results were then presented to the stakeholders through five key messages. The challenges of communicating the results in such a way with stakeholders are discussed at the end of the article.

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Delta-9-tetrahydrocannabinolic acid A (THCA-A) is the biosynthetic precursor of delta-9-tetrahydrocannabinol (THC) in cannabis plants, and has no psychotropic effects. THCA-A can be detected in blood and urine, and several metabolites have been identified. THCA-A was also shown to be incorporated in hair by side stream smoke to a minor extent, but incorporation via blood stream or sweat seems unlikely. The detection of THCA-A in biological fluids may serve as a marker for differentiating between the intake of prescribed THC medication – containing only pure THC – and cannabis products containing THC besides THC-acid A and other cannabinoids. However, the knowledge about its usefulness in forensic cases is very limited. The aim of the present work was the development of a reliable method for THCA-A determination in human blood or plasma using LC–MS/MS and application to cases of driving under the influence of drugs. Fifty eight (58) authentic whole blood and the respective plasma samples were collected from drivers suspected of driving under the influence of cannabis from the region of Bern (Switzerland). Samples were first tested for THC, 11-OH-THC and THC-COOH, and then additionally for THCA-A. For this purpose, the existing LC–MS/MS method was modified and validated, and found to be selective and linear over a range of 1.0 to 200 ng/mL (the correlation coefficients were above 0.9980 in all validation runs). Limit of detection (LOD) and limit of quantification (LOQ) were 0.3 ng/mL and 1.0 ng/mL respectively. Intra- and inter-assay accuracy were equal or better than 90% and intra- and inter-assay precision were equal or better than 11.1%. The mean extraction efficiencies were satisfactory being equal or higher than 85.4%. THCA-A was stable in whole blood samples after 3 freeze/thaw cycles and storage at 4 °C for 7 days. Re-injection (autosampler) stability was also satisfactory. THC was present in all blood samples with levels ranging from 0.7 to 51 ng/mL. THCA-A concentrations ranged from 1.0 to 496 ng/mL in blood samples and from 1.4 to 824 ng/mL in plasma samples. The plasma:blood partition coefficient had a mean value of 1.7 (±0.21, SD). No correlation was found between the degree of intoxication or impairment stated in the police protocols or reports of medical examinations and the detected THCA-A-concentration in blood.

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Different socio-economic and environmental drivers lead local communities in mountain regions to adapt land use practices and engage in protection policies. The political system also has to develop new approaches to adapt to those drivers. Local actors are the target group of those policy approaches, and the question arises of if and how much those actors are consulted or even integrated into the design of local land use and protection policies. This article addresses this question by comparing seven different case studies in Swiss mountain regions. Through a formal social network analysis, the inclusion of local actors in collaborative policy networks is investigated and compared to the involvement of other stakeholders representing the next higher sub-national or national decisional levels. Results show that there is a significant difference (1) in how local actors are embedded compared to other stakeholders; and (2) between top-down versus bottom-up designed policy processes.