Sensitivity degradation in a tri-band GSM BiCMOS direct-conversion receiver caused by transient substrate heating

An analysis of transient thermal substrate effects impairing the sensitivity of the DCS path in a tri-band GSM/DCS/PCS BiCMOS radio receiver is presented in this paper. A simple thermal model of the substrate is employed, enabling concurrent electrothermal circuit-substrate simulations within a standard analog circuit simulator. Simulation results obtained with this approach match very closely the measured data, and are used to predict the sensitivity of different circuit layout configurations to thermal gradients in the substrate. Following the guidelines suggested by these analyses, a redesigned version of the receiver displays a sensitivity improvement of 2 dB to 4 dB

Shortening Ambulance Response Time Increases Survival in Out-of-Hospital Cardiac Arrest

Background The ambulance response time in out-of-hospital cardiac arrest (OHCA) has doubled over the past 30 years in Sweden. At the same time, the chances of surviving an OHCA have increased substantially. A correct understanding of the effect of ambulance response time on the outcome after OHCA is fundamental for further advancement in cardiac arrest care. Methods and Results We used data from the SRCR (Swedish Registry of Cardiopulmonary Resuscitation) to determine the effect of ambulance response time on 30-day survival after OHCA. We included 20 420 cases of OHCA occurring in Sweden between 2008 and 2017. Survival to 30 days was our primary outcome. Stratification and multiple logistic regression were used to control for confounding variables. In a model adjusted for age, sex, calendar year, and place of collapse, survival to 30 days is presented for 4 different groups of emergency medical services (EMS)-crew response time: 0 to 6 minutes, 7 to 9 minutes, 10 to 15 minutes, and >15 minutes. Survival to 30 days after a witnessed OHCA decreased as ambulance response time increased. For EMS response times of >10 minutes, the overall survival among those receiving cardiopulmonary resuscitation before EMS arrival was slightly higher than survival for the sub-group of patients treated with compressions-only cardiopulmonary resuscitation. Conclusions Survival to 30 days after a witnessed OHCA decreases as ambulance response times increase. This correlation was seen independently of initial rhythm and whether cardiopulmonary resuscitation was performed before EMS-crew arrival. Shortening EMS response times is likely to be a fast and effective way of increasing survival in OHCA

A comparative study of the dissociation of protons into low-mass pπ+π−p\pi^{+} \pi^{-} systems in coherent and incoherent proton-nucleus collisions at 18.6 GeV/c

A decay angular moments analysis has been performed on 8500 p pi /sup +/ pi /sup -/ events produced by the interaction of high-energy protons with nuclear targets. The analysis was carried out separately for the low-t, coherent events and the high-t, incoherent events. The moments of the two samples show significant and possible reasons for such differences are discussed. (7 refs)

Coherent production of low-mass pπ+π−p\pi^{+}\pi^{-} states in the interaction of 18.6 GeV/c protons with 4He^{4}He nuclei

A specially developed scintillator and spark chamber spectrometer has been used to measure recoiling /sup 4/He target nuclei, and a magnetic spark chamber spectrometer to measure forward-going p pi /sup +/ pi /sup -/ particles, selecting coherent events by four-momentum balance. Two enhancements in the p pi /sup +/ pi /sup -/ mass spectrum are found at 1.49 and 1.71 GeV/c/sup 2/. The branching ratio of the quasi- two-body state Delta /sup ++/ pi /sup -/ is 4.2+or-8% in the 1.71 GeV /c/sup 2/ mass region. The t slope, as a function of p pi /sup +/ pi /sup -/ mass, is consistent with what can be predicted using the impulse approximation. The decay angular analysis indicates the presence of several interfering states in the 1.5 GeV/ c/sup 2/ mass region and of one state in the 1.7 GeV/c/sup 2/ mass region. There is some preference shown for t-channel helicity conservation. (15 refs)