Q-sorting and MIS Research: A Primer

Q-sort offers a powerful, theoretically grounded, and quantitative tool for examining opinions and attitudes. This article provides clear guidelines in an effort to facilitate successful understanding and application of Q-sort. Following a description of the steps of Q-sorting, an example Q-sort of MIS professors on the topic of PhD preparation is presented. The example includes details of Web-based data collection and data analysis using freeware tools. The use of Q-sorting in MIS research and issues surrounding the use of Q-sort are discussed

The actin binding proteins cortactin and HS1 are dispensable for platelet actin nodule and megakaryocyte podosome formation

A dynamic, properly organised actin cytoskeleton is critical for the production and haemostatic function of platelets. The Wiskott Aldrich Syndrome protein (WASp) and Actin-Related Proteins 2 & 3 Complex (Arp2/3 complex) are critical mediators of actin polymerisation and organisation in many cell types. In platelets and megakaryocytes, these proteins have been shown to be important for proper platelet production and function. The cortactin family of proteins (Cttn & HS1) are known to regulate WASp-Arp2/3-mediated actin polymerisation in other cell types and so here we address the role of these proteins in platelets using knockout mouse models. We generated mice lacking Cttn and HS1 in the megakaryocyte/platelet lineage. These mice had normal platelet production, with platelet number, size and surface receptor profile comparable to controls. Platelet function was also unaffected by loss of Cttn/HS1 with no differences observed in a range of platelet function assays including aggregation, secretion, spreading, clot retraction or tyrosine phosphorylation. No effect on tail bleeding time or in thrombosis models was observed. In addition, platelet actin nodules, and megakaryocyte podosomes, actin-based structures known to be dependent on WASp and the Arp2/3 complex, formed normally. We conclude that despite the importance of WASp and the Arp2/3 complex in regulating F-actin dynamics in many cells types, the role of cortactin in their regulation appears to be fulfilled by other proteins in platelets

Solvent Extraction Reagent Entrainment Effects On Zinc Electrowinning From Waste Oxide Leach Solutions

A considerable quantity of metal-containing waste oxide is generated by the primary metal industry, and under increased environmental regulation, treatment of these wastes has become viable. Hydrometallurgical processing is often appropriate and one potential treatment process for zinc oxide wastes involves leaching the oxide with an acid, purifying by a solvent extraction operation, and recovering metallic zinc by electrowinning the purified leach solution. The purification stage is frequently critical and the introduction of a solvent extraction organic reagent into the flowsheet can be detrimental to downstream processes. The object of this study was to determine the effect of organics, entrained during solution purification, on the zinc electrowinning efficiency. Zinc solvent extraction / electrowinning studies were made using di-2-ethylhexyl phosphoric acid (D2EHPA), diluted with kerosene, as the organic extractant. The stripping of the zinc from the organic phase was achieved using spent electrolyte solution. Multiple stages of zinc solvent extraction tests were performed to produce a strong acid electrolyte suitable for electrowinning tests. The entrainment of the organic extractant, from the solvent extraction stage, in the loaded spent electrolyte was found to significantly affect the current efficiency, and to change the zinc deposit morphology and orientation with concurrent modifications to the polarization behavior of the system being noted. Purification of the contaminated electrolyte with activated carbon improved the current efficiency and deposit morphology and decreased the polarization to acceptable levels. The conclusions are that the detrimental effects of entrained organic can be eliminated, and that solvent extraction processing is a viable method for the treatment of zinc containing waste oxides. © 1992

Rapid assembly of highly-functionalised difluorinated cyclooctenones via ring-closing metathesis

Building block methodology from trifluoroethanol and ringclosing metathesis using a Fürstner modification of Grubbs’ conditions allows the rapid synthesis of novel difluorinated cyclooctenones

HOPS 383: An Outbursting Class 0 Protostar in Orion

We report the dramatic mid-infrared brightening between 2004 and 2006 of HOPS 383, a deeply embedded protostar adjacent to NGC 1977 in Orion. By 2008, the source became a factor of 35 brighter at 24 microns with a brightness increase also apparent at 4.5 microns. The outburst is also detected in the submillimeter by comparing APEX/SABOCA to SCUBA data, and a scattered-light nebula appeared in NEWFIRM K_s imaging. The post-outburst spectral energy distribution indicates a Class 0 source with a dense envelope and a luminosity between 6 and 14 L_sun. Post-outburst time-series mid- and far-infrared photometry shows no long-term fading and variability at the 18% level between 2009 and 2012. HOPS 383 is the first outbursting Class 0 object discovered, pointing to the importance of episodic accretion at early stages in the star formation process. Its dramatic rise and lack of fading over a six-year period hint that it may be similar to FU Ori outbursts, although the luminosity appears to be significantly smaller than the canonical luminosities of such objects.Comment: Accepted by ApJ Letters, 6 pages, 4 figures; v2 has an updated email address for the lead autho

Preferential Myosin Heavy Chain Isoform B Expression May Contribute to the Faster Velocity of Contraction in Veins versus Arteries

Smooth muscle myosin heavy chains occur in 2 isoforms, SMA (slow) and SMB (fast). We hypothesized that the SMB isoform is predominant in the faster-contracting rat vena cava compared to thoracic aorta. We compared the time to half maximal contraction in response to a maximal concentration of endothelin-1 (ET-1; 100 nM), potassium chloride (KCl; 100 mM) and norepinephrine (NE; 10 µM). The time to half maximal contraction was shorter in the vena cava compared to aorta (aorta: ET-1 = 235.8 ± 13.8 s, KCl = 140.0 ± 33.3 s, NE = 19.8 ± 2.7 s; vena cava: ET-1 = 121.8 ± 15.6 s, KCl = 49.5 ± 6.7 s, NE = 9.0 ± 3.3 s). Reverse-transcription polymerase chain reaction supported the greater expression of SMB in the vena cava compared to aorta. SMB was expressed to a greater extent than SMA in the vessel wall of the vena cava. Western analysis determined that expression of SMB, relative to total smooth muscle myosin heavy chains, was 12.5 ± 4.9-fold higher in the vena cava compared to aorta, while SMA was 4.9 ± 1.2-fold higher in the aorta than vena cava. Thus, the SMB isoform is the predominant form expressed in rat veins, providing one possible mechanism for the faster response of veins to vasoconstrictors

‘Real-life’ reduction in cholesterol with statins, 1993 to 2002

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * Statins reduce cholesterol concentrations and cardiovascular events in randomized clinical trials. * Much less is known about their impact in the setting of normal care. WHAT THIS STUDY ADDS: * This is the first study to assess the effectiveness of lipid-lowering treatment in the general population. * We have also estimated the resultant impact on major vascular events. * We have examined the actual and potential impact of lipid-lowering treatment. AIMS: To evaluate the impact of lipid-lowering treatment on cholesterol concentrations in the setting of normal care. METHODS: This was a retrospective review of all cholesterol measurements made in Tayside, Scotland, between 1993 and 2002, linked to dispensed prescribing data for lipid-lowering drugs. It was conducted in the setting of normal care and included all patients who underwent cholesterol measurement. The main outcome measure was cholesterol concentration. RESULTS: A total of 401,489 cholesterol measurements were made on 128,240 patients over the study period. Measurements were categorized as treated and untreated according to whether patients were exposed to lipid-lowering treatment at the time the total cholesterol concentration was measured. Those categorized as untreated fell by 0.86 mmol l(-1) (13.9%) and those categorized as treated by 1.45 mmol l(-1) (23.5%). The difference between baseline and follow-up cholesterol concentrations in intention-to-treat patients was 1.53 mmol l(-1) (24%) in 2002. In the same year, mean cholesterol concentration was 4.71 mmol l(-1) (a fall of 1.65 mmol l(-1) or 25.9%) in patients judged to be taking their lipid-lowering medication, compared with 5.20 mmol l(-1) (a fall of 1.16 mmol l(-1) or 18.2%) in those judged not to be taking treatment. Cholesterol fell by 0.38 mmol l(-1) (6.3%) in a cohort of never treated patients (n = 33,679) between 1993 and 2002. CONCLUSIONS: The impact of lipid-lowering drugs on population cholesterol concentrations in the setting of normal care was significant and comparable with the cholesterol reductions seen in the setting of major statin trials, despite a significant proportion of the population receiving low dose treatment. In those subjects judged to be taking their medication, the benefits achieved were substantial. The impact of nondrug factors is indicated by the fall in population cholesterol seen in the absence of lipid-lowering treatment

Moral wrongs, disadvantages, and disability: a critique of critical disability studies

Critical disability studies (CDS) has emerged as an approach to the study of disability over the last decade or so and has sought to present a challenge to the predominantly materialist line found in the more conventional disability studies approaches. In much the same way that the original development of the social model resulted in a necessary correction to the overly individualized accounts of disability that prevailed in much of the interpretive accounts which then dominated medical sociology, so too has CDS challenged the materialist line of disability studies. In this paper we review the ideas behind this development and analyse and critique some of its key ideas. The paper starts with a brief overview of the main theorists and approaches contained within CDS and then moves on to normative issues; namely, to the ethical and political applicability of CDS