A novel single-chip RF-voltage-controlled oscillator for bio-sensing applications

A novel interdigiated capacitance (IDC) based affinity biosensor system is presented that detects C-Reactive Protein (CRP), a risk marker for cardiovascular diseases, and transmit the information to a distance location wirelessly. The biosensor system consist of a voltage controlled oscillator (VCO) and an IDC. In the presence of CRP the capacitance of the IDC changes and this directly reflects to the oscillation frequency of the VCO. In the presence of 800 ng/ml antigen the frequency of the system shifts from 1.9438 GHz to 1.94175 GHz and with 64 ug/ml frequency shifts from 1.95975 GHz to 1.94875 GHz with -120 dBc/Hz phase noise

Months-long seismicity transients preceding the 2023 MW 7.8 Kahramanmaraş earthquake, Türkiye

Short term prediction of earthquake magnitude, time, and location is currently not possible. In some cases, however, documented observations have been retrospectively considered as precursory. Here we present seismicity transients starting approx. 8 months before the 2023 MW 7.8 Kahramanmaraş earthquake on the East Anatolian Fault Zone. Seismicity is composed of isolated spatio-temporal clusters within 65 km of future epicentre, displaying non-Poissonian inter-event time statistics, magnitude correlations and low Gutenberg-Richter b-values. Local comparable seismic transients have not been observed, at least since 2014. Close to epicentre and during the weeks prior to its rupture, only scarce seismic activity was observed. The trends of seismic preparatory attributes for this earthquake follow those previously documented in both laboratory stick-slip tests and numerical models of heterogeneous earthquake rupture affecting multiple fault segments. More comprehensive earthquake monitoring together with long-term seismic records may facilitate recognizing earthquake preparation processes from other regional deformation transients

Shear wave splitting as a proxy for stress forecast of the case of the 2006 Manyas-Kus Golu (Mb = 5.3) earthquake

The 2006 Mb = 5.3 Manyas-Kus Golu (Manyas) earthquake has been retrospectively "stress-forecasted" using variations in time-delays of seismic shear wave splitting to evaluate the time and magnitude at which stress-modified microcracking reaches fracture criticality within the stressed volume where strain is released. We processed micro earthquakes recorded by 29 TURDEP (Multi-Disciplinary Earthquake Research in High Risk Regions of Turkey) and 33 KOERI (Kandilli Observatory and Earthquake Research Institute) stations in the Marmara region by using the aspect-ratio cross-correlation and systematic analysis of crustal anisotropy methods. The aim of the analysis is to determine changes in delay-times, hence changes in stress, before and after the 2006 Manyas earthquake. We observed that clear decreases in delay times before the impending event, especially at the station GEMT are consistent with the anisotropic poro-elasticity (APE) model of fluid-rock deformation, but we could not observe similar changes at other stations surrounding the main event. The logarithms of the duration of the stress-accumulation are proportional (self-similar) to the magnitude of the impending event. Although time and magnitude of th 2005 Manyas earthquake could have been stress-forecasted, as has been recognized elsewhere, shear-wave splitting does not appear to provide direct information about the location of impending earthquakes

ATTENUATION OF CODA WAVES IN WESTERN ANATOLIA

By analyzing the decay of coda wave amplitude, we have determined coda Q,Q(c), in Western Anatolia (Turkey). Using the single isotropic scattering model, we analyzed 116 earthquakes which registered at the Gebze station by using five narrow frequency bands centered at 1.5, 3, 6, 8 and 10 Hz. Coda Q values were obtained using different lapse times, between 30 and 190 s, in steps of 10 s. Coda Q(c) for Western Anatolia depends on frequency and lapse time. For a lapse time of 30 s, the frequency dependence of Q(c) is Q(c)(f) = 50.7f1.01 and for a lapse time of 190 s it is Q(c)(f) = 183.2f0.76. In this region, the exponential value of the Q(c) frequency dependence is practically constant, between 0.7 and 1.0. The obtained coda Q(c) values were compared with those estimated in other regions. The coda Q(c) values for lapse times between 60 and 100 s for Western Anatolia and Southern Spain are practically the same, indicating similar coda wave attenuation patterns in both regions of the Mediterranean Basin

Estimation of Spectral Exponent Parameter of <inline-formula><graphic file="1687-6180-2007-063219-i1.gif"/></inline-formula> Process in Additive White Background Noise

An extension to the wavelet-based method for the estimation of the spectral exponent, , in a process and in the presence of additive white noise is proposed. The approach is based on eliminating the effect of white noise by a simple difference operation constructed on the wavelet spectrum. The parameter is estimated as the slope of a linear function. It is shown by simulations that the proposed method gives reliable results. Global positioning system (GPS) time-series noise is analyzed and the results provide experimental verification of the proposed method.</p