7,469 research outputs found
Editorial Viewpoint: Overloading the Educational Circuit
A guest editoria
Career Education As An Educational Ideal
Educational philosopher Phil Smith critically examines the assumptions and arguments put forth by the advocates of Career Education. He questions the thinking behind the idea that the primary objective of the educational endeavor should be concerned with \u27\u27the development of skills in an accepting accepting job market
Wolf-Rayets in IC10: Probing the Nearest Starburst
IC10 is the nearest starburst galaxy, as revealed both by its Halpha surface
brightness and the large number of Wolf-Rayet stars (WRs) per unit area. The
relative number of known WC- to WN-type WRs has been thought to be unusually
high (~2), unexpected for IC10's metallicity. In this Letter we report the
first results of a new and deeper survey for WRs in IC10. We sucessfully
detected all of the spectroscopically known WRs, and based upon comparisons
with a neighboring control field, estimate that the total number of WRs in IC10
is about 100. We present spectroscopic confirmation of two of our WR
candidates, both of which are of WN type. Our photometric survey predicts that
the actual WC/WN ratio is ~0.3. This makes the WC/WN ratio of IC 10 consistent
with that expected for its metallicity, but greatly increases the already
unusually high number of WRs, resulting in a surface density that is about 20
times higher than in the LMC. If the majority of these candidates are
spectroscopically confirmed, IC10 must have an exceptional population of high
mass stars.Comment: Accepted by ApJL; only minor correction in this versio
Psychology and neurobiology of simple decisions
Patterns of neural firing linked to eye movement decisions show that behavioral decisions are predicted by the differential firing rates of cells coding selected and nonselected stimulus alternatives. These results can be interpreted using models developed in mathematical psychology to model behavioral decisions. Current models assume that decisions are made by accumulating noisy stimulus information until sufficient information for a response is obtained. Here, the models, and the techniques used to test them against response-time distribution and accuracy data, are described. Such models provide a quantitative link between the time-course of behavioral decisions and the growth of stimulus information in neural firing data. The question of how two-alternative decisions are made i
Remote sensing of Earth's atmosphere and surface using a digital array scanned interferometer: A new type of imaging spectrometer
The capabilities of the digital array scanned interferometer (DASI) class of instruments for measuring terrestrial radiation fields over the visible to mid-infrared are evaluated. DASI's are capable of high throughput, sensitivity and spectral resolution and have the potential for field-of-view spatial discrimination (an imaging spectrometer). The simplicity of design and operation of DASI's make them particularly suitable for field and airborne platform based remote sensing. The long term objective is to produce a versatile field instrument which may be applied toward a variety of atmospheric and surface studies. The operation of DASI and its advantages over other spectrometers are discussed
Insulin mediated upregulation of the renin angiotensin system in human subcutaneous adipocytes is reduced by Rosiglitazone
Background: Obesity associated hypertension is likely to be due to multiple mechanisms. Identification of the renin-angiotensin system (RAS) within adipose tissue does, however, suggest a potential causal role for it in obesity-associated hypertension. Obese patients are often hyperinsulinaemic, but mechanisms underlying insulin upregulation of the RAS in adipose tissue are unclear. TNFα, an inducer of angiotensinogen in hepatocytes, is elevated in hyperinsulinaemic, obese individuals, and may provide a link in mediating insulin upregulation of the RAS in adipose tissue. Further, thiazolidinediones lower blood pressure in vivo and downregulation of the RAS in adipose tissue may contribute to this effect. We therefore examined the effect of rosiglitazone (RSG), on the insulin mediated upregulation of the RAS.
Methods and Results: Sera were obtained from the arterial circulation and from venous blood draining subcutaneous abdominal adipose tissue. Isolated human abdominal subcutaneous adipocytes (n=12) were treated with insulin (1-1000nM) and insulin in combination with RSG (10nM), and RSG (10nM) alone to determine angiotensinogen expression, angiotensin II, bradykinin and TNFα secretion. Subcutaneous adipocytes were also treated with TNFα (10-100ng/mL) to examine the direct effect on angiotensinogen expression and angiotensin II secretion. The findings showed that the arterio-venous difference in angiotensin II levels was significant (↑23%; p<0.001). Insulin increased TNFα secretion in a concentration-dependent manner (p<0.01) whilst RSG (10nM) significantly reduced the insulin mediated rise in TNFα (p<0.001), as well as AGT and angiotensin II. TNFα also increased angiotensinogen and angiotensin II in isolated adipocytes.
Conclusions: Our in vivo data suggest that human subcutaneous adipose tissue is a significant source of angiotensin II. This study also demonstrates a potential TNFα mediated
mechanism through which insulin may stimulate the RAS and may contribute to explain obesity associated hypertension. RSG downregulates the RAS in subcutaneous adipose tissue and this effect may contribute to the long-term effect of RSG on blood pressure
Removal of chemical and microbial contaminants from greywater using a novel constructed wetland: GROW
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The availability of freshwater resources is becoming universally depleted, leading to the requirement for a focused management strategy for treating and reusing wastewater. In particular for urban and developing areas, small scale decentralized treatment systems are becoming popular. The GROW (Green Roof-top Water Recycling System) constructed wetland is one such option that provides a solution without a permanent land requirement and offering medium to high treatment efficiency. The performance of the GROW system was monitored from November 2013 to April 2015 in treating greywater from the Krishna Student Hostel in IIT Madras. The performance of the GROW wetland cells were examined over four monitoring periods in Phase 1 namely: 1) start-up stage, 2) seasonal variation 3) change of flow rate and 4) change in organic fraction (26.8, 25.9 and 25.5 g COD/cubic meter/day respectively). In Phase 2, the plants and the filling materials were changed and the performance of GROW wetland cells were evaluated. The system was fed with greywater at a flow rate of 62, 70, 82, 100 and 120 L/day respectively with hydraulic retention time of 0.7–1.3 days. The samples taken from the inlet and the outlets of the GROW system were taken weekly and analyzed for the following parameters; pH, COD, BOD, TSS, TN, NO 3 –N, TP, FC, SDS, PG and TMA. In the study, the overall removal efficiency was greater than 82% for all the parameters. The GROW wetlands reduced all the above mentioned parameters to within or closely to the USEPA standard limits for reuse. The reusable effluent water is named ‘Green Water’.The authors wish to acknowledge Department of Science of Technology (DST), India and the European Union for providing the financial support for the project SARASWATI
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