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Measuring conditions for second order X-ray Bragg-spectrometry
The KL2,3 (α)1,2-lines of 19K, the L3M4,5 (α)1,2-lines of 48Cd, and the M5N6,7 (α)1,2-lines of 92U are lines of comparable energy in the region of approximately 3 keV. In none of these cases were we able to resolve the three doublets when recording the spectra in first order Bragg spectrometry using a PET crystal as the dispersing element. For the purpose of enhancing the resolving power of the spectrometer, the three α spectra were recorded in second order reflection, thereby transferring the lines into another spectral region dominated by X-ray quanta of half the energy. In order to achieve high net peak intensities as well as a high peak-to-background ratio and, consequently, a high level of detection capability, the discriminator settings should be optimized quite carefully. In this manner, we were able to resolve the three α doublets and estimate α2/α1 intensity ratios. Inexplicably, current monographs, e.g., by Goldstein et al, do not contain any indications about the rational use of high order spectrometry. Only a few rather old monographs contain some hints in this regard
Business cycles, velocity and asset prices in a Wicksellian banking time economy
This thesis collects three interrelated pieces of theoretical work, which are connected to each other in the sense of being rooted in an analysis and examination of a specific type of monetary general equilibrium model which is of a cash-in-advance nature. All of the three contributions extend the usual quantity-theoretic cash-in-advance (CIA) constraint to a more general exchange constraint, in that they include the possibility of allowing the representative household to pay for the consumption good using a (self-)produced alternative means-of-exchange, costly credit. The first two pieces extend the cash costly-credit production-based monetary RBC framework to include habit persistence in consumption and adjustment costs to investment. Most of the stochastic dynamic analysis emphasizes the role of a goods-sector productivity structural shock on/t/, so the thesis focuses on telling a story of a "Wicksellian" Banking time economy, in which it is predominantly this shock alone - and its effect on the Wicksellian equilibrium real rate of interest - that is driving both real and nominal variables in the economy. The growth rate of money is assumed to be of deterministic "k-percent" Friedman-type nature, so as to allow a more focused analysis of the endogenous variation in the demand for money. While the first piece discusses how the chosen modeling framework can success fully account for some factually observed measures related to consumption-money velocity, the second piece uses a similar model setup, but instead discusses the conditional behaviour of key real and nominal variables over the business cycle. Money balances, real quantities, real and nominal rates, as well as (expected) inflation rate series move conditionally over a Solow residual-driven business cycle, so as to closely mimick some of the salient features of a stylized monetary business cycle. Noteably, the additional introduction of credit production shocks allow the artificial economy to closely mimick the breakdown of a stable money demand relationship which is such a pertinent feature of the U.S. monetary business cycle in post-1980 data. Finally, the third piece deviates marginally from the first two contributions in that it constitutes a discussion of a labour-only economy. Here, credit production is de-centralized and produced subject to a debt- (or collateral-) requirement. Specifically, the decentralized financial intermediary is assumed to retain an amount of short-term government debt equal in value to credit on it's balances sheet, which it eventually pays out as a dividend to the household, reimbursing the latter for the cost of credit. The money market rate (obtained on a one-period saving deposit) is generally lower than the usual intertemporal risk-free rate, where the difference is always equal to the banking wage bill, which varies endogenously over the business cycle. This model setup and the implied banking wage tax levied on short-term saving deposits can help to explain some of the unconditional as well as conditional behaviour of the low risk-free, the equity premium, and the unconditional shape of the term structure of interest rates
User-modelled ambient feedback for self-regulated learning
A fundamental objective of human-computer interaction research is to make systems that are seamlessly integrated into daily life activities. Hence, the challenge is not only to make information available to people at any time, at any place, and in any form, but specifically to say the right thing at the right time in the right way. On the other hand, the proliferation of sensor technology is facilitating the scaffolding and customization of smart learning environments. This manuscript presents an ecology of resources comprising NFC, BLE and Arduino technology, orchestrated in the context of a learning environment to provide smoothly integrated feedback via ambient displays. This ecology is proposed as a suitable solution for self-regulated learning, providing support for setting goals, setting aside time to learn, tracking study time and monitoring the progress. Hereby, the ecology is described and intriguing research questions are introduced
Bruton's tyrosine kinase inhibitionâAn emerging therapeutic strategy in immuneâmediated dermatological conditions
Bruton's tyrosine kinase (BTK), a member of the Tec kinase family, is critically involved in a range of immunological pathways. The clinical application of BTK inhibitors for B-cell malignancies has proven successful, and there is strong rationale for the potential benefits of BTK inhibitors in some autoimmune and allergic conditions, including immune-mediated dermatological diseases. However, the established risk-to-benefit profile of "first-generation" BTK inhibitors cannot be extrapolated to these emerging, non-oncological, indications. "Next-generation" BTK inhibitors such as remibrutinib and fenebrutinib entered clinical development for chronic spontaneous urticaria (CSU); rilzabrutinib and tirabrutinib are being studied as potential treatments for pemphigus. Promising data from early-phase clinical trials in CSU suggest potential for these agents to achieve strong pathway inhibition, which may translate into measurable clinical benefits, as well as other effects such as the disruption of autoantibody production. BTK inhibitors may help to overcome some of the shortcomings of monoclonal antibody treatments for immune-mediated dermatological conditions such as CSU, pemphigus, and systemic lupus erythematosus. In addition, the use of BTK inhibitors may improve understanding of the pathophysiological roles of mast cells, basophils, and B cells in such conditions.info:eu-repo/semantics/publishedVersio
Key Action Extraction for Learning Analytics
Proceedings of: 7th European Conference on Technology Enhanced Learning (EC-TEL 2012): 21st Century Learning for 21st Century Skills. SaarbrĂŒcken, Germany, September 18-21, 2012.Analogous to keywords describing the important and relevant content of a document we extract key actions from learners' usage data assuming that they represent important and relevant parts of their learning behaviour. These key actions enable the teachers to better understand the dynamics in their classes and the problems that occur while learning. Based on these insights, teachers can intervene directly as well as improve the quality of their learning material and learning design. We test our approach on usage data collected in a large introductory C programming course at a university and discuss the results based on the feedback of the teachers.Work partially funded by the European Communityâs Seventh Framework Programme (FP7/2007-2013) under grant agreement no 231396 (ROLE project), the Learn3 project (TIN2008-05163/TSI), the eMadrid project (S2009/TIC-1650), and the AcciÂŽon Integrada DE2009-0051.Publicad
Coronary fly-through or virtual angioscopy using dual-source MDCT data
Coronary fly-through or virtual angioscopy (VA) has been studied ever since its invention in 2000. However, application was limited because it requires an optimal computed tomography (CT) scan and time-consuming post-processing. Recent advances in post-processing software facilitate easy construction of VA, but until now image quality was insufficient in most patients. The introduction of dual-source multidetector CT (MDCT) could enable VA in all patients. Twenty patients were scanned using a dual-source MDCT (Definition, Siemens, Forchheim, Germany) using a standard coronary artery protocol. Post-processing was performed on an Aquarius Workstation (TeraRecon, San Mateo, Calif.). Length travelled per major branch was recorded in millimetres, together with the time required in minutes. VA could be performed in every patient for each of the major coronary arteries. The mean (range) length of the automated fly-through was 80 (32â107) mm for the left anterior descending (LAD), 75 (21â116) mm for the left circumflex artery (LCx), and 109 (21â190) mm for the right coronary artery (RCA). Calcifications and stenoses were visualised, as well as most side branches. The mean time required was 3Â min for LAD, 2.5Â min for LCx, and 2Â min for the RCA. Dual-source MDCT allows for high quality visualisation of the coronary arteries in every patient because scanning with this machine is independent of the heart rate. This is clearly shown by the successful VA in all patients. Potential clinical value of VA should be determined in the near future
Integration of Runtime Verification into Metamodeling
Domain Specific Modeling Languages (DSMLs) Modeling is a well-established practice in the development of big and complex software systems. Domain Specific Modeling Languages (DSMLs) are a technique used for specifying such systems in an abstract way. These languages define the structure, semantics and constraints for models related to the same application domain. The models created with DSMLs are then interconnected or related to one another. Among the reasons for tailoring a language to the problem space is their better understandability by domain experts, capacity for high-level abstraction, and user friendliness. However, the use of DSMLs (like the use of types in general) does not shield the produced software from bugs or man-made mistakes. Software failures may still occur on complex systems due to a variety of reasons such as design errors, hardware breakdown or network problems. Ruling out these failures requires that verification methods that guarantee correct execution even in corner cases are integrated into the development process. We previously presented our ideas for integrating specifications tighter with the mode
In Vivo Imaging of Vesicular Monoamine Transporters in Human Brain Using [ 11 C]Tetrabenazine and Positron Emission Tomography
The pharmacokinetics of [ 11 CJtetrabenazine, a high-affinity radioligand for the monoamine vesicular transporter, were determined in living human brain using in vivo imaging by positron emission tomography (PET). The radiotracer showed high brain uptake and rapid washout from all brain regions with relatively slower clearance from regions of highest concentrations of monoamine vesicular transporters (striatum), resulting in clear differential visualization of these structures at short intervals after injection (10â20 min). As the first human PET imaging study of a vesicular neurotransmitter transporter, these experiments demonstrate that external imaging of vesicular transporters forms a new and valuable approach to the in vivo quantification of monoaminergic neurons, with potential application to the in vivo study of neurodegenerative disorders such as Parkinson's disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65743/1/j.1471-4159.1993.tb03521.x.pd
Sirolimus and kidney growth in autosomal dominant polycystic kidney disease
BACKGROUND: In autosomal dominant polycystic kidney disease (ADPKD), aberrant activation of the mammalian target of rapamycin (mTOR) pathway is associated with progressive kidney enlargement. The drug sirolimus suppresses mTOR signaling. METHODS: In this 18-month, open-label, randomized, controlled trial, we sought to determine whether sirolimus halts the growth in kidney volume among patients with ADPKD. We randomly assigned 100 patients between the ages of 18 and 40 years to receive either sirolimus (target dose, 2 mg daily) or standard care. All patients had an estimated creatinine clearance of at least 70 ml per minute. Serial magnetic resonance imaging was performed to measure the volume of polycystic kidneys. The primary outcome was total kidney volume at 18 months on blinded assessment. Secondary outcomes were the glomerular filtration rate and urinary albumin excretion rate at 18 months. RESULTS: At randomization, the median total kidney volume was 907 cm(3) (interquartile range, 577 to 1330) in the sirolimus group and 1003 cm(3) (interquartile range, 574 to 1422) in the control group. The median increase over the 18-month period was 99 cm(3) (interquartile range, 43 to 173) in the sirolimus group and 97 cm(3) (interquartile range, 37 to 181) in the control group. At 18 months, the median total kidney volume in the sirolimus group was 102% of that in the control group (95% confidence interval, 99 to 105; P=0.26). The glomerular filtration rate did not differ significantly between the two groups; however, the urinary albumin excretion rate was higher in the sirolimus group. CONCLUSIONS: In adults with ADPKD and early chronic kidney disease, 18 months of treatment with sirolimus did not halt polycystic kidney growth. (ClinicalTrials.gov number, NCT00346918.
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