Large Igneous Provinces (LIPs) are emerging as a significant driver of short duration climatic change including mass extinctions. Here we compare the record of LIPs against the timing of Devonian ...biotic crises that are well recorded in the numerous anoxia events throughout this period. The largest LIPs are two-pulse events at ca. 370 and ca. 360 Ma that are present in both Siberia (Yakutsk-Vilyui LIP) and Baltica (Kola-Dnieper LIP) and correlate with the Kellwasser anoxia events (late Frasnian) and Annulata or Dasberg and Hangenberg anoxia events in the late/latest Famennian. The regionally significant Altai Sayan LIP is only approximately dated at c.400 Ma and within uncertainties could be linked to either (or both?) the c. 405 Ma Chebbi or Atopus anoxia events near the basal Emsian (associated with graptolite extinction) or the c. 385–390 Ma group of anoxia events in the Eifelian or Givetian.
Additional magmatic events that are less precisely dated are: 1) the c. 400–345 Ma Kedon magmatism of the Omolon craton, possibly linked with the Yakutsk-Vilyui event, 2) 380–330 Ma Maritimes (Magdalen) basin event of the Appalachian region of eastern Canada and adjacent US, 3) middle-late Devonian Selwyn basin alkaline magmatism of northwestern Canada, and 4) the Ordovician - late Silurian- possibly Devonian Soltan Maidan event Iran. However, more precise dating is required for each of these magmatic events before they can be properly compared with the Devonian biotic crisis record.
•Pulses of 380–360 Ma Yakutsk-Vilyui & Kola-Dnieper LIPs linked with late Frasnian and middle/late Famennian anoxia events•Ca. 400 Ma Altay-Sayan LIP correlated withearly Devonian biotic crises.•Other magmatic events (Soltan Maidan, Magdalen, Selwyn basin) need precise dating to evaluate any anoxia links
Research on radiation-tolerant electronics has increased rapidly over the past few years, resulting in many interesting approaches to modeling radiation effects and designing radiation-hardened ...integrated circuits and embedded systems. This research is strongly driven by the growing need for radiation-hardened electronics for space applications, high-energy physics experiments such as those on the Large Hadron Collider at CERN, and many terrestrial nuclear applications including nuclear energy and nuclear safety. With the progressive scaling of integrated circuit technologies and the growing complexity of electronic systems, their susceptibility to ionizing radiation has raised many exciting challenges, which are expected to drive research in the coming decade. In this book we highlight recent breakthroughs in the study of radiation effects in advanced semiconductor devices, as well as in high-performance analog, mixed signal, RF, and digital integrated circuits. We also focus on advances in embedded radiation hardening in both FPGA and microcontroller systems and apply radiation-hardened embedded systems for cryptography and image processing, targeting space applications.
This paper provides an overview and makes a deep investigation on sampled-data-based event-triggered control and filtering for networked systems. Compared with some existing event-triggered and ...self-triggered schemes, a sampled-data-based event-triggered scheme can ensure a positive minimum inter-event time and make it possible to jointly design suitable feedback controllers and event-triggered threshold parameters. Thus, more attention has been paid to the sampled-data-based event-triggered scheme. A deep investigation is first made on the sampled-data-based event-triggered scheme. Then, recent results on sampled-data-based event-triggered state feedback control, dynamic output feedback control, H ∞ filtering for networked systems are surveyed and analyzed. An overview on sampled-data-based event-triggered consensus for distributed multiagent systems is given. Finally, some challenging issues are addressed to direct the future research.
Cerebrospinal and structural‐molecular neuroimaging in‐vivo biomarkers are recommended for diagnostic purposes in Alzheimer’s disease (AD) and other dementias; however, they do not explain the ...effects of AD neuropathology on neurophysiological mechanisms underpinning cognitive processes. Here, an Expert Panel from the Electrophysiology Professional Interest Area of the Alzheimer’s Association reviewed the field literature and reached consensus on the event‐related electroencephalographic oscillations (EROs) that show consistent abnormalities in patients with significant cognitive deficits due to Alzheimer’s, Parkinson’s (PD), Lewy body (LBD), and cerebrovascular diseases. Converging evidence from oddball paradigms showed that, as compared to cognitively unimpaired (CU) older adults, AD patients had lower amplitude in widespread delta (>4 Hz) and theta (4–7 Hz) phase‐locked EROs as a function of disease severity. Similar effects were also observed in PD, LBD, and/or cerebrovascular cognitive impairment patients. Non‐phase‐locked alpha (8–12 Hz) and beta (13–30 Hz) oscillations were abnormally reduced (event‐related desynchronization, ERD) in AD patients relative to CU. However, studies on patients with other dementias remain lacking. Delta and theta phase‐locked EROs during oddball tasks may be useful neurophysiological biomarkers of cognitive systems at work in heuristic and intervention clinical trials performed in AD patients, but more research is needed regarding their potential role for other dementias.
A multidisciplinary Expert Panel reviewed the literature and reached a consensus on the event‐related electroencephalographic oscillations (EROs) showing consistent abnormalities in patients with significant cognitive deficits due to Alzheimer’s, Parkinson’s (PD), Lewy body (LBD), and cerebrovascular diseases. Delta and theta phase‐locked EROs during oddball tasks may be useful as neurophysiological biomarkers of cognitive systems at work in AD patients, although those EEG measures were unspecific in relation to the other dementing disorders mentioned above.
Event History Modeling, first published in 2004, provides an accessible guide to event history analysis for researchers and advanced students in the social sciences. The substantive focus of many ...social science research problems leads directly to the consideration of duration models, and many problems would be better analyzed by using these longitudinal methods to take into account not only whether the event happened, but when. The foundational principles of event history analysis are discussed and ample examples are estimated and interpreted using standard statistical packages, such as STATA and S-Plus. Critical innovations in diagnostics are discussed, including testing the proportional hazards assumption, identifying outliers, and assessing model fit. The treatment of complicated events includes coverage of unobserved heterogeneity, repeated events, and competing risks models. The authors point out common problems in the analysis of time-to-event data in the social sciences and make recommendations regarding the implementation of duration modeling methods.
It has long been hypothesized that the linguistic structure of events, including event participants and their relative prominence, draws on the non-linguistic nature of events and the roles that ...these events license. However, the precise relation between the prominence of event participants in language and cognition has not been tested experimentally in a systematic way. Here we address this gap. In four experiments, we investigate the relative prominence of (animate) Agents, Patients, Goals and Instruments in the linguistic encoding of complex events and the prominence of these event roles in cognition as measured by visual search and change blindness tasks. The relative prominence of these event roles was largely similar—though not identical—across linguistic and non-linguistic measures. Across linguistic and non-linguistic tasks, Patients were more salient than Goals, which were more salient than Instruments. (Animate) Agents were more salient than Patients in linguistic descriptions and visual search; however, this asymmetrical pattern did not emerge in change detection. Overall, our results reveal homologies between the linguistic and non-linguistic prominence of individual event participants, thereby lending support to the claim that the linguistic structure of events builds on underlying conceptual event representations. We discuss implications of these findings for linguistic theory and theories of event cognition.
We extend event system theory (EST) to conceptualize proactive events and examine how event duration, timing, criticality, and disruption are related to two phases of change associated with an ...organizationally initiated event. Specifically, we explore the impact of a new sustainability monitoring system on energy consumption using longitudinal archival data from 87 manufacturing units of a Fortune 200 multinational firm. We use a variant of mixed-effects discontinuous growth modeling (DGM) to test EST propositions related to initial and longer-term changes associated with implementing the monitoring system. Results indicate that while the new sustainability monitoring system is effective in reducing within-unit energy consumption on average, there are significant differences in change magnitude between units. The magnitude of change during the pre-post phase was related to between-unit differences in event duration, timing, criticality, and disruption. Longer-term change patterns were related to between-unit differences in managerial criticality behaviors. The results empirically validate several of EST’s core propositions and provide an illustration of how DGM can be modified to study events that vary in onset and duration across entities.
There is a lack of high-resolution records of hydroclimate variability in the Eastern Mediterranean from the late glacial and early Holocene. More knowledge of the speed of climate shifts and the ...degree to which they were synchronous with changes in the North Atlantic or elsewhere is required to understand better the controls on Eastern Mediterranean climate. Using endogenic carbonate from a sediment sequence from Nar Gölü, a maar lake in central Turkey, dated by varve counting and uranium-thorium methods, we present high-resolution (∼25 years) oxygen (δ18O) and carbon isotope records, supported by carbonate mineralogy data, spanning the late glacial and Holocene. δ18Ocarbonate at Nar Gölü has been shown previously to be a strong proxy for regional water balance. After a dry period (i.e. evaporation far exceeding precipitation) in the Younger Dryas, the data show a transition into the relatively wetter early Holocene. In the early Holocene there are two drier periods that appear to peak at ∼9.3 ka and ∼8.2 ka, coincident with cooling ‘events’ seen in North Atlantic records. After this, and as seen in other records from the Eastern Mediterranean, there is a millennial-scale drying trend through the Mid Holocene Transition. The relatively dry late Holocene is punctuated by centennial-scale drought intervals, at the times of 4.2 ka ‘event’ and Late Bronze Age societal ‘collapse’. Overall, we show that central Turkey is drier when the North Atlantic is cooler, throughout this record and at multiple timescales, thought to be due to a weakening of the westerly storm track resulting from reduced cyclogenesis in the North Atlantic. However, some features, such as the Mid Holocene Transition and the fact the early Holocene dry episodes at Nar Gölü are of a longer duration than the more discrete ‘events’ seen in North Atlantic records, imply there are additional controls on Eastern Mediterranean hydroclimate.
•Sub-centennial resolution late glacial and Holocene isotope record from Turkey.•Rapid transition from a dry late glacial into a wet early Holocene.•Drier anomalies apparently at times of 9.3 ka and 8.2 ka events but last longer at Nar.•Droughts at times of 4.2 ka event and Late Bronze Age societal ‘collapse’.•Strong teleconnection with North Atlantic, but additional other drivers.
This study proposes a new process‐based framework to characterize and classify runoff events of various magnitudes occurring in a wide range of catchments. The framework uses dimensionless indicators ...that characterize space–time dynamics of precipitation events and their spatial interaction with antecedent catchment states, described as snow cover, distribution of frozen soils, and soil moisture content. A rigorous uncertainty analysis showed that the developed indicators are robust and regionally consistent. Relying on covariance‐ and ratio‐based indicators leads to reduced classification uncertainty compared to commonly used (event‐based) indicators based on absolute values of metrics such as duration, volume, and intensity of precipitation events. The event typology derived from the proposed framework is able to stratify events that exhibit distinct hydrograph dynamics even if streamflow is not directly used for classification. The derived typology is therefore able to capture first‐order controls of event runoff response in a wide variety of catchments. Application of this typology to about 180,000 runoff events observed in 392 German catchments revealed six distinct regions with homogeneous event type frequency that match well regions with similar behavior in terms of runoff response identified in Germany. The detected seasonal pattern of event type occurrence is regionally consistent and agrees well with the seasonality of hydroclimatic conditions. The proposed framework can be a useful tool for comparative analyses of regional differences and similarities of runoff generation processes at catchment scale and their possible spatial and temporal evolution.
Key Points
A new process‐based framework for characterizing runoff events of diverse sizes is proposed and applied to a wide set of catchments
Novel indicators combining the space–time dynamics of event precipitation and catchment state are used for classification
The derived event typology captures distinct shapes of event hydrographs even if streamflow data are not directly used for classification
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