Pharmacologic profile of survivors of acute myocardial infarction at United States academic hospitals

Optimal drug therapy for patients with acute myocardial infarction (AMI) is well described in the medical literature. However, data on the actual pharmacologic management of patients surviving AMI at academic hospitals is unavailable. The purpose of this study was to document treatment profiles in 500 patients surviving AMI at 12 academic hospitals in the United States. These profiles were compared with established guidelines and were evaluated for trends. Overall, thrombolytics (streptokinase > or = tissue-type plasminogen activator) were administered in 29% of the patients, with a greater proportion of patients receiving beta-blockers than calcium channel antagonists in the initial 72 hours (61% vs 40%; p < 0.005) and at discharge (51% vs 35%; p < 0.005). Further, women were less likely than men to receive thrombolytic therapy (odds ratio [OR] = 0.61; confidence interval [CI], 0.54 to 0.69) or beta-blocker therapy within the first 72 hours (OR = 0.61; CI, 0.55 to 0.67) or at hospital discharge (OR = 0.53; CI, 0.48 to 0.58). Overall, improvements could still be made in the number of patients who receive thrombolytic and acute and chronic beta-blocker therapies after AMI, particularly in women. Changes in treatment profiles may be a reflection of the publication of large clinical trials.     

Jet ventilation in a case of tracheal obstruction secondary to a retrosternal goitre

Intermittent jet ventilation was used during anaesthesia in a 66-yr-old woman who had severe tracheal narrowing secondary to compression by a retrosternal goitre. The trachea was intubated by a small-bore tube, which was placed above the site of narrowing. An injector was connected to the proximal end of the tracheal tube on one side and to the anaesthesia circuit on the other. Intermittent jets of 66% nitrous oxide in oxygen via the injector resulted in adequate oxygenation and carbon dioxide elimination. Arterial blood gas analysis during jet ventilation showed PaO2 150 mmHg, PaCO2 35 mmHg and pH 7.4. It is concluded that low-frequency jet ventilation may provide adequate oxygenation and carbon dioxide elimination in the presence of tracheal narrowing.     

A review of self-assembled monolayers as potential terahertz frequency tunnel diodes

In this review, we describe the principles of the tunnel junction, self-assembled monolayer （SAM） application techniques, experimental testbed fabrication, and characterization of the films and devices. In addition, techniques for directed application, removal, and functionalization of the monolayers are discussed. Bottom-up fabrication techniques have seen increased attention because of their versatility and ease of use. These films see mechanical uses as surface modifiers and micro-scale lubricants. Advances in nanowatt electronics and ultra-low power sensors have opened up an energy harvesting niche for solutions which would have proven ineffective just some years ago. The focus of this study is the two- terminal junction which has potential applications in THz rectification for energy harvesting, medical imaging, and defense sensing. The quantum theory of operation behind these devices is touched on briefly---describing tunneling through the organic monolayers. Commentary on trends in research and potential future work are presented as well.     

Optimal policies for integrating heterogeneous services on isdn channels

A technique for the classification and evaluation of hierarchical access integration policies of ISDN channels is proposed. The essence of the basic control decisions based on several parameters of the servers and channel is captured in a single priority-based-layered model of multiple queues. We solve for the resulting delay of different policies and investigate the performance in one tractable limit of this model. Using our understanding of the problem parameters and their interaction, we propose a number of heuristic policies for the general model. The results of the general problem complexity investigations suggest the use of simulation models. Problem parameters considered are channel acceptable access delay value, number of servers needed, and flow duration time of a request. Preemptive and non-pre-emptive policies on queued traffic are considered. Performance considers average delay, delay variation and channel utilization. Simulation data on these policies suggest that policies that favour shorter services given better overall delay over a wide range of system parameters. Policies that favour longer and broadband services, on the other hand, show better quality and smaller delay variation.     

A fluorescent temperature probe based on the association between the excited states of 4-(N,N-dimethylamino)benzonitrile and beta-cyclodextrin

A temperature probe based on the fluorescence properties of the two excited states of 4-(N,N-dimethylamino)benzonitrile (DMABN) in equilibrium with beta-cyclodextrin (CD) in aqueous solution is presented. The fluorescence intensity of the Franck-Condon excited state (FB) as a function of temperature shows a straight line with a correlation better than 0.99 in the 283-308 K temperature interval. On the other hand, the fluorescence intensity of the twisted internal charge-transfer state (FA) remains constant in the same temperature interval because the binding of DMABN in the A* state to CD is isoenthalpic and entropy driven. It is found that the FA/FB ratio is independent of the excitation intensity at a specified temperature, shows a linear relationship with temperature, and allows temperature measurements with a resolution of +/- 2.5 K.     

Corrosion Inhibition of mild steel in aqueous solution containing H2S by some naturally occurring substances

The corrosion inhibition of mild steel by some naturally occuring substance was evaluated in absence and presence of 600 and 1200 mg H₂S/l in 3% NaCl aqueous solution and pH of 3 and temperature of 25 °C. These naturally occurring substance included the water extracts, coumarines and fatty matters extracts of some Egyptian plants. These plants included: (1) Nigella Sativa (Family Ranunculacease) (Extract (1), 2) Coriandrum Sativum (Family Umbelliferea) (Extract II), 3) Ricinus communis (Family Euphorbiaceae) (Extract III). The galvanostatic anodic and cathodic polarization measurements were used for studying the corrosion behavior of mild steel and evaluation of the percentage inhibition of the undertesting extracts of these three plants and also preparation of fatty matters and coumarin fractions were mentioned.     

Liquid Fuels from Alternative Carbon Sources Minimizing Carbon Dioxide Emissions

The energy needs of the world continue to grow, as does the resulting environmental impact. Policy makers continue to call for alternative energies to replace today's petroleum‐based liquid fuels. However, liquid fuels have significant advantages, and it is probably unwise to abandon the existing infrastructure without appropriately exploring alternatives to lessen the environmental burden of producing liquid fuels. Biomass and coal are often proposed as alternatives to petroleum‐based carbon sources, but those processes lose a significant amount of their potential product to unwanted carbon dioxide emissions. However, combining biomass and coal with cleaner natural gas yields processes with less environmental impact to produce liquid fuels with small, zero, or even negative carbon dioxide emissions. Our process synthesis approach is applied to commonly encountered liquid fuel production methods to identify promising routes and to establish feasibility limits on those less promising alternatives. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2062–2078, 2013     

Corrosion inhibition of mild steel by amphoteric surfactants derived from aspartic acid

The inhibition of mild steel corrosion/in 0.5 M HCl solution by amphoteric surfactants (which contain both an anionic and a cationic moiety in the same molecule) of general formula: (R alkyl group of C_{10, 11, 12, 13, 15 and 17}) is shown to confirm Langmuir's adsorption isotherms. At a given concentration of surfactants, the inhibiting action increases with the increase of carbon chain length. The influence of both inductive and steric hindrance effects of methylene groups in –R on the inhibition efficiency has also been mentioned.