State University of New York System

About: State University of New York System is a education organization based out in Albany, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 54077 authors who have published 78070 publications receiving 2985160 citations.

Single Atomic Iron Catalysts for Oxygen Reduction in Acidic Media: Particle Size Control and Thermal Activation.

Abstract: It remains a grand challenge to replace platinum group metal (PGM) catalysts with earth-abundant materials for the oxygen reduction reaction (ORR) in acidic media, which is crucial for large-scale deployment of proton exchange membrane fuel cells (PEMFCs). Here, we report a high-performance atomic Fe catalyst derived from chemically Fe-doped zeolitic imidazolate frameworks (ZIFs) by directly bonding Fe ions to imidazolate ligands within 3D frameworks. Although the ZIF was identified as a promising precursor, the new synthetic chemistry enables the creation of well-dispersed atomic Fe sites embedded into porous carbon without the formation of aggregates. The size of catalyst particles is tunable through synthesizing Fe-doped ZIF nanocrystal precursors in a wide range from 20 to 1000 nm followed by one-step thermal activation. Similar to Pt nanoparticles, the unique size control without altering chemical properties afforded by this approach is able to increase the number of PGM-free active sites. The best O...

Metformin: an update.

Abstract: Metformin is an insulin-sensitizing agent with potent antihyperglycemic properties. Its efficacy in reducing hyperglycemia in type 2 diabetes mellitus is similar to that of sulfonylureas, thiazolidinediones, and insulin. Metformin-based combination therapy is often superior to therapy with a single hypoglycemic agent. The antihyperglycemic properties of metformin are mainly attributed to suppressed hepatic glucose production, especially hepatic gluconeogenesis, and increased peripheral tissue insulin sensitivity. Although the precise mechanism of hypoglycemic action of metformin remains unclear, it probably interrupts mitochondrial oxidative processes in the liver and corrects abnormalities of intracellular calcium metabolism in insulin-sensitive tissues (liver, skeletal muscle, and adipocytes) and cardiovascular tissue.

Sexual scripts: permanence and change.

Abstract: A general introduction to scripting theory is offered, attempting to provide links between macrolevel considerations of sociocultural development and general theories of individual development. The scripting of behavior is examined on three distinct levels: cultural scenarios (instruction in collective meanings), interpersonal scripts (the application of specific cultural scenarios by a specific individual in a specific social context), and intrapsychic scripts (the management of desires as experienced by the individual). These concepts of the scripting of behavior are then applied to sexual behavior. Interpersonal scripts are seen as the ordering of representations of self and other that facilitate the occurrence of a sexual act; intrapsychic scripts represent the ordering of images and desires that elicit and sustain sexual arousal. Issues of stability and change in sexual scripts are then examined in terms of the changing circumstances and requirements associated with movement through the life cycle.

Pharmacodynamics of intravenous ciprofloxacin in seriously ill patients.

Abstract: Seventy-four acutely ill patients were treated with intravenous ciprofloxacin at dosages ranging between 200 mg every 12 h and 400 mg every 8 h. A population pharmacokinetic-pharmacodynamic analysis relating drug exposure (and other factors) to infectious outcome was performed. Plasma samples were obtained and assayed for ciprofloxacin by high-performance liquid chromatography. Samples from patients were frequently cultured so that the day of bacterial eradication could be determined. The pharmacokinetic data were fitted by iterative two-stage analysis, assuming a linear two-compartment model. Logistic regression was used to model ciprofloxacin exposure (and other potential covariates) versus the probabilities of achieving clinical and microbiologic cures. The same variables were also modelled versus the time to bacterial eradication by proportional hazards regression. The independent variables considered were dose, site of infection, infecting organism and the MIC for it, percent time above the MIC, peak, peak/MIC ratio, trough, trough/MIC ratio, 24-h area under the concentration-time curve (AUC), AUC/MIC ratio (AUIC), presence of other active antibacterial agents, and patient characteristics. The most important predictor for all three measures of ciprofloxacin pharmacodynamics was the AUIC. A 24-h AUIC of 125 SIT-1.h (inverse serum inhibitory titer integrated over time) was found to be a significant breakpoint for probabilities of both clinical and microbiologic cures. At an AUIC below 125 (19 patients), the percent probabilities of clinical and microbiologic cures were 42 and 26%, respectively. At an AUIC above 125 (45 patients), the probabilities were 80% (P < 0.005) and 82% (P < 0.001), respectively. There were two significant breakpoints in the time-to-bacterial-eradication data. At an AUIC below 125 (21 patients), the median time to eradication exceeded 32 days; at an AUIC of 125 to 250 (15 patients), time to eradication was 6.6 days: and at AUIC above 250 (28 patients), the median time to eradication was 1.9 days (groups differed; P < 0.005). These findings, when combined with pharmacokinetic data reported in the companion article, provide the rationale and tools needed for targeting the dosage of intravenous ciprofloxacin to individual patients' pharmacokinetics and their bacterial pathogens' susceptibilities. An a priori dosing algorithm (based on MIC, patient creatine clearance and weight, and the clinician-specified AUIC target) was developed. This approach was shown, retrospectively, to be more precise than current guidelines, and it can be used to achieve more rapid bacteriologic and clinical responses to ciprofloxacin, as a consequence of targeting the AUIC.

Quantum superposition of distinct macroscopic states

Abstract: In 1935, Schrodinger attempted to demonstrate the limitations of quantum mechanics using a thought experiment in which a cat is put in a quantum superposition of alive and dead states. The idea remained an academic curiosity until the 1980s when it was proposed that, under suitable conditions, a macroscopic object with many microscopic degrees of freedom could behave quantum mechanically, provided that it was sufficiently decoupled from its environment. Although much progress has been made in demonstrating the macroscopic quantum behaviour of various systems such as superconductors, nanoscale magnets, laser-cooled trapped ions, photons in a microwave cavity and C60 molecules, there has been no experimental demonstration of a quantum superposition of truly macroscopically distinct states. Here we present experimental evidence that a superconducting quantum interference device (SQUID) can be put into a superposition of two magnetic-flux states: one corresponding to a few microamperes of current flowing clockwise, the other corresponding to the same amount of current flowing anticlockwise.