The unwanted amplification of monochromatic signals in seismic noise cross-correlation functions by spectral whitening

The estimation of the Green’s function between two points on the Earth’s surface by the cross-correlation of seismic noise time series requires, in general, very long time series (months to years) as well as massive normalisation. Spectral whitening is a widely used powerful normalisation to improve the emergence of broad-band signals in seismic noise cross-correlations. Nevertheless, we observe spectral whitening to depend strongly on the time window length necessarily used to fragment very long time series. An unwanted amplification of a persistent microseism signal is observed on the continental scale with time windows shorter than 12 hours

Seismic Interferometry at the TIMO2-network, Germany

Using seismic interferometry, we analyze the seismic noise wavefield around the city of Landau, Germany. The crosscorrelation functions (CCFs) are investigated with respect to signals which might contain information on the underground and its temporal variations. The used data set comes from the TIMO2-project (TIMO: Deep Structure of the Central Upper Rhine Graben). Since the summer of 2009, seismic stations have been installed especially to detect induced seismicity in the region of Landau. The obtained CCFs are dominated by signals with frequencies between 0.4 and 0.8 Hz which are strongly asymmetric. We will present the results of the ongoing work to characterize and identify the source(s) of these signals

Editorial special issue: PHM for railway systems and mass transportation

The railway and mass transportation system is composed of industrial goods with substantial capital investments and long life cycles. This applies to rolling stock like trains, locomotives, wagons, and even more to the infrastructure like signaling, catenary, tracks, bridges, and tunnels. The lifespan of rolling stock is 30 to 40 years while the infrastructure is used 30 to 60 years even more than 100 years in case of tunnels and bridges. As in other industrial goods, the cost drivers are determined in the early design phases but realized mainly during a long time of operation. Maintenance is one of the main cost drivers but essential to a reliable, capable, and – above all – safe operation

A first attempt to model region-wide glacier surface mass balances in the Karakoram: findings and future challenges

In contrast to the central and eastern part of High Mountain Asia (HMA), no extensive glacier mass loss has been observed in the Karakoram during previous decades. However, the potential meteorological and glaciological causes of the so-called Karakoram Anomaly are diverse and still under debate. This paper introduces and presents a novel glacier Surface Mass Balance Model (glacierSMBM) to test whether the characteristic regional mass balance pattern can be reproduced using recent field, remote-sensing and reanalysis data as input. A major advantage of the model setup is the implementation of the non-linear effect of supra-glacial debris on the sub-surface ice melt. In addition to a first assessment of the annual surface mass balance from 1st August 2010 until 31st July 2011, a sensitivity analysis was performed to investigate the response of Karakoram glaciers to recent climate change. The mean modelled glacier mass balance for the Karakoram during the observation period is -0.92 m water equivalent (w.e.) a-1 and corresponds to an annual melt water contribution of ~12.66 km3. Data inaccuracies and the neglected process of snow redistribution from adjacent slopes are probably responsible for the bias in the model output. Despite the general offset between mass gain and mass loss, the model captures the characteristic features of the anomaly and indicates that positive glacier mass balances are mainly restricted to the central and northeastern part of the mountain range. From the evaluation of the sensitivity analysis, it can be concluded that the complex glacier response in the Karakoram is not the result of a single driver, but related to a variety of regional peculiarities such as the favourable meteorological conditions, the extensive supra-glacial debris and the timing of the main precipitation season

Fault Reactivation Analysis Using Microearthquake Clustering Based on Signal-to-Noise Weighted Waveform Similarity

The cluster formation of about 2000 induced microearthquakes (mostly M L < 2) is studied using a waveform similarity technique based on cross-correlation and a subsequent equivalence class approach. All events were detected within two separated but neighbouring seismic volumes close to the geothermal powerplants near Landau and Insheim in the Upper Rhine Graben, SW Germany between 2006 and 2013. Besides different sensors, sampling rates and individual data gaps, mainly low signal-to-noise ratios (SNR) of the recordings at most station sites provide a complication for the determination of a precise waveform similarity analysis of the microseismic events in this area. To include a large number of events for such an analysis, a newly developed weighting approach was implemented in the waveform similarity analysis which directly considers the individual SNRs across the whole seismic network. The application to both seismic volumes leads to event clusters with high waveform similarities within short (seconds to hours) and long (months to years) time periods covering two magnitude ranges. The estimated relative hypocenter locations are spatially concentrated for each single cluster and mirror the orientations of mapped faults as well as interpreted rupture planes determined from fault plane solutions. Depending on the waveform cross-correlation coefficient threshold, clusters can be resolved in space to as little as one dominant wavelength. The interpretation of these observations implies recurring fault reactivations by fluid injection with very similar faulting mechanisms during different time periods between 2006 and 2013

Distributed global debris thickness estimates reveal debris significantly impacts glacier mass balance

International audienc

Quantitative trait loci conferring grain mineral nutrient concentrations in durum wheat 3 wild emmer wheat RIL population

Mineral nutrient malnutrition, and particularly deficiency in zinc and iron, afflicts over 3 billion people worldwide. Wild emmer wheat, Triticum turgidum ssp. dicoccoides, genepool harbors a rich allelic repertoire for mineral nutrients in the grain. The genetic and physiological basis of grain protein, micronutrients (zinc, iron, copper and manganese) and macronutrients (calcium, magnesium, potassium, phosphorus and sulfur) concentration was studied in tetraploid wheat population of 152 recombinant inbred lines (RILs), derived from a cross between durum wheat (cv. Langdon) and wild emmer (accession G18-16). Wide genetic variation was found among the RILs for all grain minerals, with considerable transgressive effect. A total of 82 QTLs were mapped for 10 minerals with LOD score range of 3.2–16.7. Most QTLs were in favor of the wild allele (50 QTLs). Fourteen pairs of QTLs for the same trait were mapped to seemingly homoeologous positions, reflecting synteny between the A and B genomes. Significant positive correlation was found between grain protein concentration (GPC), Zn, Fe and Cu, which was supported by significant overlap between the respective QTLs, suggesting common physiological and/or genetic factors controlling the concentrations of these mineral nutrients. Few genomic regions (chromosomes 2A, 5A, 6B and 7A) were found to harbor clusters of QTLs for GPC and other nutrients. These identified QTLs may facilitate the use of wild alleles for improving grain nutritional quality of elite wheat cultivars, especially in terms of protein, Zn and Fe

A case study of Kanban implementation within the Pharmaceutical Supply Chain

The paper explores the implementation of the kanban system, which is a Lean technique, within the Pharmaceutical Supply Chain (PSC). The case study provides insight to the benefits and challenges arising from the application of this technique, within a group of cooperative pharmacists, in Greece. The research questions developed from the review of the literature were tested using evidence from field-based, action research within a pharmaceutical organisation. The reported case study contributes to the longer term debate on assessing the Lean maturity level within the healthcare sector. There are two primary findings: i) that the adoption of kanban system provides a strategic benefit and improves the quality of services. ii) it also provides a basis for a strategy of operational change; it gives the opportunity to the organisation to move away from the current push delivery and logistics systems toward improved logistics strategy models

Response of the Human Circadian System to Millisecond Flashes of Light

Ocular light sensitivity is the primary mechanism by which the central circadian clock, located in the suprachiasmatic nucleus (SCN), remains synchronized with the external geophysical day. This process is dependent on both the intensity and timing of the light exposure. Little is known about the impact of the duration of light exposure on the synchronization process in humans. In vitro and behavioral data, however, indicate the circadian clock in rodents can respond to sequences of millisecond light flashes. In a cross-over design, we tested the capacity of humans (n = 7) to respond to a sequence of 60 2-msec pulses of moderately bright light (473 lux) given over an hour during the night. Compared to a control dark exposure, after which there was a 3.5±7.3 min circadian phase delay, the millisecond light flashes delayed the circadian clock by 45±13 min (p<0.01). These light flashes also concomitantly increased subjective and objective alertness while suppressing delta and sigma activity (p<0.05) in the electroencephalogram (EEG). Our data indicate that phase shifting of the human circadian clock and immediate alerting effects can be observed in response to brief flashes of light. These data are consistent with the hypothesis that the circadian system can temporally integrate extraordinarily brief light exposures

BK Channels Regulate Spontaneous Action Potential Rhythmicity in the Suprachiasmatic Nucleus

Background: Circadian (,24 hr) rhythms are generated by the central pacemaker localized to the suprachiasmatic nucleus (SCN) of the hypothalamus. Although the basis for intrinsic rhythmicity is generally understood to rely on transcription factors encoded by ‘‘clock genes’’, less is known about the daily regulation of SCN neuronal activity patterns that communicate a circadian time signal to downstream behaviors and physiological systems. Action potentials in the SCN are necessary for the circadian timing of behavior, and individual SCN neurons modulate their spontaneous firing rate (SFR) over the daily cycle, suggesting that the circadian patterning of neuronal activity is necessary for normal behavioral rhythm expression. The BK K + channel plays an important role in suppressing spontaneous firing at night in SCN neurons. Deletion of the Kcnma1 gene, encoding the BK channel, causes degradation of circadian behavioral and physiological rhythms. Methodology/Principal Findings: To test the hypothesis that loss of robust behavioral rhythmicity in Kcnma1 2/2 mice is due to the disruption of SFR rhythms in the SCN, we used multi-electrode arrays to record extracellular action potentials from acute wild-type (WT) and Kcnma1 2/2 slices. Patterns of activity in the SCN were tracked simultaneously for up to 3 days, and the phase, period, and synchronization of SFR rhythms were examined. Loss of BK channels increased arrhythmicity but also altered the amplitude and period of rhythmic activity. Unexpectedly, Kcnma1 2/2 SCNs showed increased variability in the timing of the daily SFR peak