Stroke volume measurement during supine and upright cycle exercise by impedance cardiography

This study evaluated impedance cardiography (ZCG) estimates of stroke volume (SV) during exercise. Seven subjects were studied at rest and during progressive cycle exercise in supine and upright positions. SV was determined by ZCG (SVZCG) during exercise and for the first 5 cardiac cycles following exercise. SVZCG was compared with separate measurements of SV by CO2 rebreathing (SVCO2). Static blood resistivity (p) was measured at each level of exercise. No significant differences were found between supine exercise and immediate post-exercise values for the peak of the first derivative of the impedance change (dZ/dtmax), left ventricular ejection time (LVET), or SVZCG. Small differences in dZ/dtmax and SVZCG, but not LVET, were found in exercise to post-exercise cycling in the upright position. Intra-individual SVZCG and SVCO2 were moderately correlated (upright mean r = 0.64, supine r = 0.42) from rest to 70% of peak VO2. Similar correlations were found between Pulse-O2 (VO2/heart rate, used as an index to SV) and both SVZCG (upright r = 0.73, supine r = 0.57) and SVCO2 (upright r = 0.8, supine r = 0.65). The ZCG parameters dZ/dtmax and LVET correlated better with Pulse-O2 (dZ/dtmax: upright r = 0.92, supine r = 0.73; LVET: upright r = -0.9, supine r = -0.9). SVZCG calculated with the Kubicek equation performed as well as SVCO2. ZCG might be a superior method if the inversely correlated parameters, dZ/dtmax and LVET, were not expressed as a product to calculate SV.     

Magnetic nanocomposites for environmental remediation

This article provides an overview of current research activities on the synthesis and applications of magnetic nanocomposites, especially highlights their potential environmental remediations such as heavy metal (Cr, As, Pd, Hg) removal. After a brief introduction of the emergency situation of heavy metal pollution all over the world and current techniques designed to deal with these situations, different synthetic methods to fabricate various types of magnetic nanocomposites will be reviewed. The focus is to reveal the advantages of magnetic nanocomposites as an efficient adsorbent which is able to reduce the heavy metal concentrations well below the EPA requirement. At the same time, the conventional process can be redesigned to be an economic and energetic one without using extra energy to recycle the adsorbent, which is desired for future. This review mainly deals with the heavy metal removal using magnetic nanocomposites, the adsorption behaviors of heavy metal ions on the surface of novel adsorbents are well investigated including the concentration effect of both contaminants and adsorbents, adsorption kinetics, solution pH effect with regards to real application.     

Energy efficiency as a preferred resource: evidence from utility resource plans in the Western US and Canada

This article examines the future role of energy efficiency as a resource in the Western US and Canada, as envisioned in the most recent resource plans issued by 16 utilities, representing about 60% of the region’s load. Utility and third-party-administered energy-efficiency programs proposed by 15 utilities over a 10-year horizon would save almost 19,000 GWh annually, about 5.2% of forecast load. There are clear regional trends in the aggressiveness of proposed energy savings. California’s investor-owned utilities (IOUs) had the most aggressive savings targets, followed by IOUs in the Pacific Northwest, and the lowest savings were proposed by utilities in Inland West states and by two public utilities on the West Coast. The adoption of multiple, aggressive policies targeting energy efficiency and climate change appears to produce sizeable energy-efficiency commitments. Certain specific policies, such as mandated energy savings goals for California’s IOUs and energy-efficiency provisions in Nevada’s Renewable Portfolio Standard, had a direct impact on the level of energy savings included in the resource plans. Other policies, such as revenue decoupling and shareholder incentives and voluntary or legislatively mandated greenhouse gas emission reduction policies, may have also impacted utilities’ energy-efficiency commitments, though the effects of these policies are not easily measured. Despite progress among the utilities in our sample, more aggressive energy-efficiency strategies that include high-efficiency standards for additional appliances and equipment, tighter building codes for new construction and renovation, as well as more comprehensive ratepayer-funded energy-efficiency programs are likely to be necessary to achieve a region-wide goal of meeting 20% of electricity demand with efficiency in 2020.

A descriptive epidemiology of netball injuries during competition: a five year study

As new knowledge is being acquired about the highly polymorphic apolipoprotein (a) gene, studies are also being directed at elucidating the factors involved in the synthesis and maturation of apolipoprotein (a) and the determinants controlling the interactions between apolipoprotein (a) and apolipoprotein B100 in lipoprotein (a) assembly. It is now apparent that apolipoprotein (a) is not only size but also sequence polymorphic and that some of the mutations within the lysine-binding site potentially impair the binding of apolipoprotein (a) to lysine-rich domains, such as those in fibrin(ogen) and apolipoprotein B100. At present, there is little knowledge about the effect of the lipoprotein (a) polymorphism on the mechanisms underlying its atherothrombogenic potential. With the current availability of in-vitro, ex-vivo, and transgenic mice models, this issue should be amenable to productive exploration.     

Design and Use of an Integrated Cambridge Ring

The Cambridge ring is a local area network used both in universities and industry. It is based on the empty slot principle and data are transmitted using minipackets containing two bytes of data. This paper describes the design process, decisions, and tradeoffs in implementing an integrated system which incorporates both analog and digital components. The technology chosen is a bipolar gate array. A number of options are provided for the implementor who can optimize network parameters such as minipacket size and transmission speed to his needs. He can also choose the style of interface between the communicating device and the network. An important option provided by the integrated Cambridge ring is the ability to simultaneously transmit short control minipackets and long data packets. A system exploiting this feature has been built and is described. Its proposed uses are to interconnect telephones and other real-time systems as well as computers where the partitioning of bandwidth and precise performance specification are important.     

Feline immunodeficiency virus infection. Clinicopathologic findings in 90 naturally occurring cases

Cytogenetic analysis of 184 adipose tissue tumors, 175 lipomas, and nine liposarcomas (LPS) showed the presence of a ring chromosome and/or a long marker chromosome in 10 cases with common histologic features such as atypical stromal cells with or without lipoblasts. In five of the cases, this appeared to be the sole cytogenetic abnormality. Fluorescence in situ hybridization (FISH) analysis with a microclone library specific for chromosome region 12q13-q15 showed extensive staining of the ring and long marker chromosomes, indicating that genetic sequences of this particular region of chromosome 12 are present in these marker chromosomes, most likely in an amplified form.     

The Anatomy of a Context-Aware Application

We describe a sensor-driven, or sentient, platform for context-aware computing that enables applications to follow mobile users as they move around a building. The platform is particularly suitable for richly equipped, networked environments. The only item a user is required to carry is a small sensor tag, which identifies them to the system and locates them accurately in three dimensions. The platform builds a dynamic model of the environment using these location sensors and resource information gathered by telemetry software, and presents it in a form suitable for application programmers. Use of the platform is illustrated through a practical example, which allows a user's current working desktop to follow them as they move around the environment.