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In this Letter, an opamp-free noise shaping successive-approximation register (SAR) ADC is proposed. Third-order noise shaping is achieved by implementing a second-order passive filter and a passive error feedback topology. In the proposed scheme, the SAR error signals (including quantisation noise, comparator thermal noise, DAC thermal noise and settling error) are subjected to third-order noise shaping. Therefore, the thermal noise specifications of the comparator can be relaxed. Also, since no active element is used, the proposed scheme achieves a higher power efficiency than earlier SAR ADCs.

Background: Multivessel (MV) disease is present in a significant number of patients with non-ST-segment elevation myocardial infarction (NSTEMI). The optimal revascularization strategy in these patients is uncertain. Methods: PROMETHEUS was a multicenter observational study of patients undergoing

Background: African American (AA) patients are at high risk for adverse cardiovascular outcomes after PCI, thus providing a rationale for use of potent P2Y12 inhibitors in such individuals. However, whether or not race is a determinant of prasugrel versus clopidogrel use in acute coronary syndrome (

Obesity is major health problem. Abdominal obesity is associated with the metabolic syndrome, coronary artery disease (CAD) and heart failure (HF). It is unclear if abdominal obesity is associated with left ventricular (LV) dysfunction independently of hypertension (HTN), CAD and weight among

The determinants of clinical decision-making for potent platelet inhibition with prasugrel versus clopidogrel in real-world patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) remain poorly characterized. The purpose of this study was to identify factors

The contemporary incidence, associated factors and implications of stroke after acute coronary syndromes (ACS) managed with percutaneous coronary intervention (PCI) and novel antiplatelet drugs is unknown. We sought to characterize the incidence, predictors and impact of stroke on subsequent

Anthracycline therapy is associated with a life-threatening but poorly understood cardiotoxicity. Effects of treatment are consistent with drug-induced disruption of cardiac sarcoplasmic reticulum (SR) calcium homeostasis, including inhibition of calcium release by anthracyclines. This effect, which depends on luminal SR calcium concentration, is hypothesized to involve interactions of anthracyclines with the calcium binding protein calsequestrin (CSQ). This study was designed to test the hypothesis that an interaction between CSQ and anthracyclines could be related to alterations in SR calcium release and cardiac function. The effects of the anthracycline, daunorubicin, and its metabolite daunorubicinol were compared with those of a known CSQ inhibitor, trifluoperazine (TFP). Protein fluorescence quenching studies demonstrated that TFP, daunorubicin, and daunorubicinol bind to CSQ with apparent binding affinities in the low micromolar range. The presence of calcium decreases the drug-dependent fluorescence quenching, probably because of calcium-induced CSQ conformational changes. TFP also inhibited SR calcium release. Although the TFP IC50 value is somewhat larger than for anthracyclines, the TFP effect is also dependent on luminal SR calcium concentration. In a muscle preparation, micromolar TFP decreased cardiac contractility in a manner that implicates the involvement of SR calcium and resembles the effects of anthracyclines. These data are consistent with a mechanism in which TFP or anthracyclines impair SR calcium release and cardiac function through a mechanism involving disruption of CSQ function. Such a mechanism may contribute to anthracycline cardiotoxicity.

Urea is 85% of the recycled nitrogen in a life support system. Urea is quickly converted to NH4 + but nitrification to NO3 - is difficult. Supplying NH4 + directly to plants eliminates the need for a nitrifying bioreactor. Most plant physiology textbooks indicate that NH4 + is toxic to plants, but we now know that this may not be true if pH is rigorously controlled. However, the longterm effects of high NH4 + /NO3 - uptake ratios are poorly understood. In four studies, two cultivars of wheat were grown to maturity with NH4 + /NO3 - ratios from 0 to 0.85 in recirculating hydroponic solution. In the third and fourth studies, NH4 + was supplied as (NH 4)2SO4, NH 4Cl, or both. Contrary to conventional wisdom, there was no beneficial effect of supplying 25% of the N as NH4 + compared to a nitrate control. The high NH4 + treatment (85% NH4 + ) reduced seed yield by 20% in the first two studies, but yield was not reduced in the third and fourth studies. Increasing calcium and potassium supply in the nutrient solution appears to be critical to ameliorating the detrimental effects of NH 4 + . Seed protein concentration was increased from 17 to 22% at the highest NH4 + level. These studies indicate that it may be possible to eliminate the need to recycle N as NO3 - in regenerative