Predictive value of C-reactive protein and troponin T in patients with unstable angina: a comparative analysis

AbstractOBJECTIVESWe evaluated C-reactive protein (CRP) and troponin T (TnT) for predicting six-month cardiac risk in patients with unstable angina.BACKGROUNDTroponin T is predictive of cardiac risk in patients with unstable angina. The clinical implications of elevated CRP in such patients remains controversial.METHODSBaseline TnT and CRP values were determined in 447 patients with unstable angina enrolled in the placebo group of the Chimeric c7E3 AntiPlatelet Therapy in Unstable angina REfractory to standard treatment trial (CAPTURE) trial. All patients underwent a coronary intervention and were followed for a six month period in which 13 deaths and 47 myocardial infarctions were documented (MIs).RESULTSTroponin T was >0.1 μg/liter in 30% and CRP was >10 mg/L in 41% of the patients. For the initial 72-h period (including coronary intervention), TnT (17.4% vs. 4.2%; p < 0.001) but not CRP (10.3% vs. 8%; p = 0.41) was predictive of mortality and MI. The TnT-positive patients displayed more frequent recurrent instability before the planned intervention (44.8% vs. 16.9%; p < 0.001), but in the CRP-positive patients, no such increase was observed (25.9% vs. 24.8%; p = 0.92). In contrast, for the six month follow-up period, CRP was predictive of cardiac risk (mortality, MI) (18.9% vs. 9.5%; p = 0.003). Using multivariate analysis, both CRP and TnT emerged as independent predictors of mortality and MI at six- month follow-up. Furthermore, the incidence of coronary restenosis during six-month follow-up was not related to TnT status (3% vs. 4.5%; p = 0.49); however, it was significantly related to CRP status (7% vs. 2.3%; p = 0.03).CONCLUSIONSTroponin T, but not CRP, was predictive of cardiac risk during the initial 72-h period, whereas CRP was an independent predictor of both cardiac risk and repeated coronary revascularization (coronary artery bypass graft surgery and percutaneous transluminal coronary angioplasty) during six month follow-up

Livestock grazing and biodiversity : effects on CO2 exchange in semi-arid Karoo ecosystems, South Africa

DATA AVAILABILITY : Data used in this study can be obtained upon request and will be made available through the FLUXNET database.Livestock use in semi-arid South African ecosystems has not been extensively studied in relation to the Net Ecosystem Exchange (NEE) of carbon dioxide (CO2). We present four years of measurements from twinned eddy-covariance towers in Nama-Karoo, South Africa, to investigate the carbon fluxes and the impact of grazing intensity on NEE. The design contrasted NEE at a long-term site grazed at recommended levels (LG) with a long-term heavily grazed (EG) site that had been rested for 10 years, and was monitored for two years after which intensive grazing was reintroduced for this experiment. This allowed for the quantification of long-term NEE trends on “recovering” vegetations (years I, II) and short-term responses to an intensified land use (years III, IV). The results showed that the net release of CO2 was slightly higher at LG than on “recovering” vegetation at the EG site, where near-neutral exchange was observed during years I and II. However, after grazing was reintroduced to the EG site, differences between sites was reduced but not eliminated. These findings suggest that there is a somewhat higher carbon sequestration potential at the resting EG site than at the LG site, apparently associated with the dominance of unpalatable drought-tolerant grass species and local elimination of many palatable shrubs. Reduction of this sink potential by reintroduction of high-intensity grazing indicates the sensitivity of C-sequestration in this “recovering” system to heavy grazing, but underlines continued resilience of NEE under far heavier grazing than in the LG system. These data suggest notable trade-offs in these ecosystems between carbon storage, biodiversity, and livestock production with rainfall variability being a critical inter-annual driver.This study suggests that long-term resting of previously over-utilized southern African semi-arid vegetation supports enhanced carbon sequestration potential, even if over-utilization has transformed vegetation composition (i.e. has caused degradation through reduced plant species richness). However, this enhanced carbon sequestration potential can be quickly negated by the reintroduction of grazing, even after 10 years of resting. Achievement of carbon sequestration is dependent on average to above-average precipitation and its distribution throughout the year, with sink activity evident mainly after seasonal rains during the warm season.he German Federal Ministry of Education and Research (BMBF), research programs SPACES and SPACES II (Science Partnerships for the Assessment of Complex Earth System Processes in Southern Africa), projects ARS AfricaE and EMSAfrica.https://www.elsevier.com/locate/scitotenvhj2024Geography, Geoinformatics and MeteorologySDG-15:Life on lan

Fundamentals of electronic systems design

This textbook covers the design of electronic systems from the ground up, from drawing and CAD essentials to recycling requirements. Chapter by chapter, it deals with the challenges any modern system designer faces: the design process and its fundamentals, such as technical drawings and CAD, electronic system levels, assembly and packaging issues and appliance protection classes, reliability analysis, thermal management and cooling, electromagnetic compatibility (EMC), all the way to recycling requirements and environmental-friendly design principles. Enables readers to face various challenges of designing electronic systems, including coverage from various engineering disciplines; Written to be accessible to readers of varying backgrounds; Uses illustrations extensively to reinforce fundamental concepts; Organized to follow essential design process, although chapters are self-contained and can be read in any order

Compact All-Optical Precision-Tunable Narrowband Hard Compton X-Ray Source

Readily available bright X-ray beams with narrow bandwidth and tunable energy promise to unlock novel developments in a wide range of applications. Among emerging alternatives to large-scale and costly present-day radiation sources which severely restrict the availability of such beams, compact laser-plasma-accelerator-driven inverse Compton scattering sources show great potential. However, these sources are currently limited to tens of percent bandwidths, unacceptably large for many applications. Here, we show conceptually that using active plasma lenses to tailor the electron bunch-photon interaction, tunable X-ray and gamma beams with percent-level bandwidths can be produced. The central X-ray energy is tunable by varying the focusing strength of the lens, without changing electron bunch properties, allowing for precision-tuning the X-ray beam energy. This method is a key development towards laser-plasma-accelerator-driven narrowband, precision tunable femtosecond photon sources, enabling a paradigm shift and proliferation of compact X-ray applications

Design Study of a Laser-driven X-ray Source for Medical Imaging

The combination of laser-wakefield acceleration and Thomsonscattering (TS) driven by one high-power laser allows for all-opticalbrilliant X-ray sources of compact design. Such source designs enablethe clinical implementation of X-ray-based medical imaging modalitiessuch as X-ray fluorescence imaging (XFI). XFI offers the in-vivolocalization of functionalized gold nanoparticles (GNPs) with highsensitivity, temporal and spatial resolution at low dose exposure. Thisrequires hard X-ray sources (~100 keV) of specific design parameters,i.e. a pencil-shaped X-ray beam within a small bandwidth and a highphoton flux to achieve feasible exposure times. Thus, optimization ofthe TS process is required to enhance the X-ray source to fulfill thegiven criteria. In this poster we show the techniques employed for thedetermination of the best laser and electron parameters. The designconcept and simulation results for a first proof-of-principle experimentare presented. Electron focusing via an active plasma lens allows forsingle-element symmetric focusing on the one hand. On the other handX-ray bandwidth control for broadband electron energy spectra (no energyspread limit) is achieved

Development of a non-invasive diagnostic for local acceleration gradient and dephasing length

FLASHForward is a beam-driven plasma wakefield accelerator located at Deutsches Elektronen Synchrotron (DESY) in Hamburg, Germany. Within the FLASHForward project, a laser-driven wakefield setup is used as testbed for the characterisation and development of diagnostics for plasma wakefield accelerators. These include different non-invasive charge diagnostics that are also tested for their usability in EMP noisy plasma environment. Another method investigated is Thomson Scattering, the interaction of relativistic electron bunches with a laser pulse resulting in x-ray beams. Results on using the dependence of the Thomson beam on the initial electron bunch parameters to study the electron bunches are presented

Advanced bandwidth control of an all-optical inverse Compton source

Bright, high-energy X-ray beam sources with narrow bandwidths and tunable energies hold great potential for widespread use in a variety of novel applications as alternatives to large-scale and costly radiation sources. Inverse Compton scattering sources based on electron beams from laser-plasma accelerators represent a promising candidate for increasing availability. However, in practice these sources are currently limited to bandwidths of tens of percent, making them unsuitable for many applications. We present results of a proof-of-principle experiment designed to mitigate these restrictions using an active plasma lens to tailor the electron-photon interaction, allowing for reduced bandwidth and tunability of the generated radiation. In the experiments, tunability of the central X-ray energy in the range from 34 keV to 81 keV was demonstrated by changing the focusing strength of the plasma lens. At the same time, bunch shaping by the plasma lens reduced the bandwidth of the produced photon beams. Our results closely follow theory, highlighting the potential of this technique as a future small-scale high-quality X-ray source that provides bandwidth and X-ray energy control

Stability of Ionisation-Injection-Based Laser-Plasma Accelerators

Laser-plasma acceleration (LPA) is a compact technique to accelerate electron bunches to highly relativistic energies, making it a promising candidate to power radiation sources for industrial or medical applications. We report on the generation of electron beams from an 80MeV-level LPA setup based on ionisation injection (II) over a duration of 8 hours at a repetition rate of 2.5 Hz, resulting in 72000 consecutive shots with charge injection and acceleration. Over the full operation time the moving averages of the total beam charge of 14.5 pC and the charge between 70-80 MeV did not drift on a detectable level. The largest source of shot-to-shot jitter was in the beam charge (26% standard deviation), which was most strongly correlated with fluctuations in the plasma density (3.6% standard deviation). Particle-in-cell simulations demonstrate that this was chiefly caused by stronger laser self-focusing in higher density plasmas, which significantly increased the ionised charge along with the emittance of the beam. The nonlinearity of this process imposes tight constraints on the reproducibility of the laser-plasma conditions required for a low jitter II-LPA output ifself-focusing plays a role in the laser evolution