Quartz ball valve

A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports

The marginated pool

The pulmonary circulation harbors a large intravascular reservoir of leukocytes refered to as the Marginated Pool. This marginated pool is balanced by propeling and retaining forces acting on leukocytes during their passage through the pulmonary circulation. The present paper discusses these factors and their underlying mechanisms. Copyright (C) 2002 S. Karger AG, Basel

Platelet kinetics in the pulmonary microcirculation in vivo assessed by intravital microscopy

Growing evidence supports the substantial pathophysiological impact of platelets on the development of acute lung injury. Methods for studying these cellular mechanisms in vivo are not present yet. The aim of this study was to develop a model enabling the quantitative analysis of platelet kinetics and platelet-endothelium interaction within consecutive segments of the pulmonary microcirculation in vivo. New Zealand White rabbits were anesthetized and ventilated. Autologous platelets were separated from blood and labeled ex vivo with rhodamine 6G. After implantation of a thoracic window, microhemodynamics and kinetics of platelets were investigated by intravital microscopy. Velocities of red blood cells (RBCs) and platelets were measured in arterioles, capillaries and venules, and the number of platelets adhering to the microvascular endothelium was counted. Kinetics of unstimulated platelets was compared with kinetics of thrombin-activated platelets. Velocity of unstimulated platelets was comparable to RBC velocity in all vessel segments. Unstimulated platelets passed the pulmonary microcirculation without substantial platelet-endothelial interaction. In contrast, velocity of activated platelets was decreased in all vascular segments indicating platelet margination and temporal platelet-endothelium interaction. Thrombin-activated platelets adhered to arteriolar endothelium; in capillaries and venules adherence of platelets was increased 8-fold and 13-fold, respectively. In conclusion, using intravital microscopy platelet kinetics were directly analyzed in the pulmonary microcirculation in vivo for the first time. In contrast to leukocytes, no substantial platelet-endothelium interaction occurs in the pulmonary microcirculation without any further stimulus. In response to platelet activation, molecular mechanisms enable adhesion of platelets in arterioles and venules as well as retention of platelets within capillaries. Copyright (C) 2002 S. Karger AG, Basel

Grassland futures in Great Britain – Productivity assessment and scenarios for land use change opportunities

This is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).To optimise trade-offs provided by future changes in grassland use intensity, spatially and temporally explicit estimates of respective grassland productivities are required at the systems level. Here, we benchmark the potential national availability of grassland biomass, identify optimal strategies for its management, and investigate the relative importance of intensification over reversion (prioritising productivity versus environmental ecosystem services). Process-conservative meta-models for different grasslands were used to calculate the baseline dry matter yields (DMY; 1961–1990) at 1 km2 resolution for the whole UK. The effects of climate change, rising atmospheric [CO2] and technological progress on baseline DMYs were used to estimate future grassland productivities (up to 2050) for low and medium CO2 emission scenarios of UKCP09. UK benchmark productivities of 12.5, 8.7 and 2.8 t/ha on temporary, permanent and rough-grazing grassland, respectively, accounted for productivity gains by 2010. By 2050, productivities under medium emission scenario are predicted to increase to 15.5 and 9.8 t/ha on temporary and permanent grassland, respectively, but not on rough grassland. Based on surveyed grassland distributions for Great Britain in 2010 the annual availability of grassland biomass is likely to rise from 64 to 72 million tonnes by 2050. Assuming optimal N application could close existing productivity gaps of ca. 40% a range of management options could deliver additional 21 ∗ 106 tonnes of biomass available for bioenergy. Scenarios of changes in grassland use intensity demonstrated considerable scope for maintaining or further increasing grassland production and sparing some grassland for the provision of environmental ecosystem services.Peer reviewedFinal Published versio

Shimmers of Truth in the Art of Theatre

Many Christians have noted Romans 1:20’s statement that God is reflected in His creation. As a theater student, I have found this to be true even in how theatrical artists actually execute their craft. Thus, for my senior honors thesis I have decided to further study this connection between the Lord and theater, for which I expect to find more of what I have already found in parallels between the Christian walk and theater arts. For the completion of this thesis, research for theatrical content will include acting and design, and research for biblical content will include the Bible and prominent theologians such as John Piper and John MacArthur. This information will then be organized, analyzed, and elaborated on in regards to the connection between theatre and theology. The result will be a collection of devotionals specifically related to the theatrical artist’s craft and work

Lethality of \u3ci\u3eBacillus anthracis\u3c/i\u3e Spores Due to Short Duration Heating Measured Using Infrared Spectroscopy

There are a number of analytical and semi-empirical models that describe the behavior of particulate matter in the atmosphere. Many of these require modification for all types of weather, dry versus wet deposition, and overall effects can be quite non-linear. Rainfall (rate, drop size, etc.), snowfall (rate, flake size, etc.), humidity, pressure, temperature, and combination of these greatly affect particle settling and washout rates. To that end, a method for tracking released constituents using the Regional Atmospheric Modeling System (RAMS) microphysics package is developed by modifying one of the hydrometeor categories (hail) in the microphysics package. The RAMS microphysics package allows the investigator to change the formulation of the parameterization scheme of the model for different applications, such as a regional-scale numerical study versus a small continental cumulus simulation. In this study, four test simulations are conducted, two with precipitation and two during dry conditions, each with two different mean particle sizes. Modified RAMS simulations using the larger mean particle size have similar deposition patterns to the Hazard Prediction and Assessment Capability (HPAC) version 4.04 simulations using location time and meteorological data. Advantages to using RAMS for particulate tracking as opposed to using a non-forecasting dispersion model include more realistic plume and fallout patterns and continuous feedback into the numerical forecast of the tracked particulate effects

Testosterone And Interpersonal Attraction: A Placebo-Controlled Design

Testosterone has long been implicated as a neuroendocrinological mechanism in the expression of reproductive strategies. Humans the world over form and maintain pair-bonds suggesting that pair-bonds may serve to enhance reproductive fitness. However, infidelity is a perennial threat to these bonds. The data in humans suggests that testosterone is associated with mate-seeking but may be detrimental to relationship maintenance. However, past work has relied on correlational studies and additional findings from nonhuman animal models suggest that acute changes rather than baseline concentrations in testosterone may in fact protect extant pair-bonds. The present research sought to test the causal role of testosterone in both mate-seeking [single men] and relationship maintenance [paired men] behaviors and perception using a between subject, double blind, placebo treatment protocol. The study recruited 212 healthy men, roughly half of whom were in a committed relationship and half single. The participants were briefly exposed to an attractive female confederate during which time the participants’ verbal and non-verbal behavior was recorded. Results indicated that among single men, testosterone moderated the effects of several of the confederate’s proceptivity behaviors on men’s self-presentation, such that her affiliative behavior was positively correlated with the men’s self-presentation. These results were restricted to single men; testosterone did not alter men’s courtship behavior among paired men, suggesting that acute changes in testosterone may not serve as a relationship protection mechanism in men. Additionally, testosterone caused men, regardless of relationship status, to perceive the confederate’s self-presentation behavior as indicative of her sexual interest. The results provide the first causal evidence for testosterone as a mate-seeking mechanism in healthy adult men and provide an outline to the psychological pathways through which testosterone alters men’s mating psychologies