Clearing the Air on Radon Testing: The Duty of Real Estate Brokers to Protect Prospective Homebuyers

This Note recommends that the federal government create legislation that will impose a duty on real estate brokers to test homes for radon and to disclose the results to prospective purchasers. Based on a common law negligence theory, such a duty would become part of the current obligation of a real estate broker: (1) to conduct a reasonably diligent and competent search of property for sale; and (2) to disclose to prospective homebuyers all material defects affecting the value or desirability of the home. In his investigation, the broker must use the expertise and knowledge that derive from his training and experience as a professional. Initially, the Note addresses the dilemma of the homebuyer who discovers radon only after occupying the home and who has no formally defined cause of action based on common law precedent or statute. Part II traces the development of a real estate broker\u27s liability in negligence to the recently imposed duty to discover and disclose latent defects. Part III analyzes the duty to discover and disclose latent defects with respect to radon and concludes that real estate brokers should have an affirmative duty to test for radon and to disclose the results to prospective purchasers. Finally, part IV recommends legislation to protect the unwary homebuyer who otherwise would take possession of the home and suffer potential economic loss and exposure to a carcinogenic substance

Arithmetical properties of Multiple Ramanujan sums

In the present paper, we introduce a multiple Ramanujan sum for arithmetic functions, which gives a multivariable extension of the generalized Ramanujan sum studied by D. R. Anderson and T. M. Apostol. We then find fundamental arithmetic properties of the multiple Ramanujan sum and study several types of Dirichlet series involving the multiple Ramanujan sum. As an application, we evaluate higher-dimensional determinants of higher-dimensional matrices, the entries of which are given by values of the multiple Ramanujan sum.Comment: 19 page

A progressive refinement approach for the visualisation of implicit surfaces

Visualising implicit surfaces with the ray casting method is a slow procedure. The design cycle of a new implicit surface is, therefore, fraught with long latency times as a user must wait for the surface to be rendered before being able to decide what changes should be introduced in the next iteration. In this paper, we present an attempt at reducing the design cycle of an implicit surface modeler by introducing a progressive refinement rendering approach to the visualisation of implicit surfaces. This progressive refinement renderer provides a quick previewing facility. It first displays a low quality estimate of what the final rendering is going to be and, as the computation progresses, increases the quality of this estimate at a steady rate. The progressive refinement algorithm is based on the adaptive subdivision of the viewing frustrum into smaller cells. An estimate for the variation of the implicit function inside each cell is obtained with an affine arithmetic range estimation technique. Overall, we show that our progressive refinement approach not only provides the user with visual feedback as the rendering advances but is also capable of completing the image faster than a conventional implicit surface rendering algorithm based on ray casting

Bcc 4^4He as a Coherent Quantum Solid

In this work we investigate implications of the quantum nature of bcc $^{4}$% He. We show that it is a unique solid phase with both a lattice structure and an Off-Diagonal Long Range Order of coherently oscillating local electric dipole moments. These dipoles arise from the local motion of the atoms in the crystal potential well, and oscillate in synchrony to reduce the dipolar interaction energy. The dipolar ground-state is therefore found to be a coherent state with a well defined global phase and a three-component complex order parameter. The condensation energy of the dipoles in the bcc phase stabilizes it over the hcp phase at finite temperatures. We further show that there can be fermionic excitations of this ground-state and predict that they form an optical-like branch in the (110) direction. A comparison with 'super-solid' models is also discussed.Comment: 12 pages, 8 figure

The controlled teleportation of an arbitrary two-atom entangled state in driven cavity QED

In this paper, we propose a scheme for the controlled teleportation of an arbitrary two-atom entangled state $|\phi>_{12}=a|gg>_{12}+b|ge>_{12}+c|eg>_{12}+d|ee>_{12}$ in driven cavity QED. An arbitrary two-atom entangled state can be teleported perfectly with the help of the cooperation of the third side by constructing a three-atom GHZ entangled state as the controlled channel. This scheme does not involve apparent (or direct) Bell-state measurement and is insensitive to the cavity decay and the thermal field. The probability of the success in our scheme is 1.0.Comment: 10 page

The Effects of Atmospheric Dispersion on High-Resolution Solar Spectroscopy

We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly significant for solar physics because the Sun is often best observed at low elevations, and the effect of the image displacement is not merely a loss of efficiency, but the mixing of information originating from different points on the solar surface. We calculate the magnitude of the atmospheric dispersion for the Sun during the year and examine the problems produced by this dispersion in both spectrographic and filter observations. We describe an observing technique for scanning spectrograph observations that minimizes the effects of the atmospheric dispersion while maintaining a regular scanning geometry. Such an approach could be useful for the new class of high-resolution solar spectrographs, such as SPINOR, POLIS, TRIPPEL, and ViSP

Hierarchical Organization in Complex Networks

Many real networks in nature and society share two generic properties: they are scale-free and they display a high degree of clustering. We show that these two features are the consequence of a hierarchical organization, implying that small groups of nodes organize in a hierarchical manner into increasingly large groups, while maintaining a scale-free topology. In hierarchical networks the degree of clustering characterizing the different groups follows a strict scaling law, which can be used to identify the presence of a hierarchical organization in real networks. We find that several real networks, such as the World Wide Web, actor network, the Internet at the domain level and the semantic web obey this scaling law, indicating that hierarchy is a fundamental characteristic of many complex systems

Deep-vein thrombosis in Europe — Burden of illness in relationship to healthcare resource utilization and return to work

Objectives: Deep-vein thrombosis (DVT) forms a major healthcare burden in Europe, but exact estimates concerning the economic burden on society are lacking. This study reports results from the PREFER in VTE study concerning resource utilization and absence from work in DVT patients. Methods: The PREFER in VTE registry was a prospective, observational, multicenter study carried out in Europe (France, Italy, Spain, the UK, and DACH [Germany, Switzerland and Austria]), designed to provide data concerning treatment patterns, resource utilization, mortality and quality of life. Patients with a first-time and/or recurrent DVT, were recruited and followed for 12 months. Data about resource utilization concerns resource utilization related to DVT. Specifically, treatment pattern, re-hospitalization rate, length of hospital stay, ambulatory/office visit, and proportion of patients returning to work, were analyzed and presented. Subgroup analysis by country and active cancer were also conducted. The length of hospital stay was analyzed as a function of demographics, previous events and co-morbidities using zero-inflated binomial negative regression. Similarly, time until return to work was analyzed using Cox regression. Results: A total of 2056 patients with DVT were recruited, with an average age of 60 years. Patients with active cancer were mostly treated with heparin (83.9%), while patients without active cancer were treated with combinations of heparin, VKA and DOACs. DOACs were less often used in Spain and Italy (30% did not return to work within the year. Conclusions: Medical treatment of DVT differed between patients with active cancer and those without. Post-VTE or VTE-related resource utilization differs remarkably between countries. Work-loss seems high, but questions may be raised concerning the causality due to the presence of co-morbidities

Naked Singularity Formation In f(R) Gravity

We study the gravitational collapse of a star with barotropic equation of state $p=w\rho$ in the context of $f({\mathcal R})$ theories of gravity. Utilizing the metric formalism, we rewrite the field equations as those of Brans-Dicke theory with vanishing coupling parameter. By choosing the functionality of Ricci scalar as $f({\mathcal R})=\alpha{\mathcal R}^{m}$, we show that for an appropriate initial value of the energy density, if $\alpha$ and $m$ satisfy certain conditions, the resulting singularity would be naked, violating the cosmic censorship conjecture. These conditions are the ratio of the mass function to the area radius of the collapsing ball, negativity of the effective pressure, and the time behavior of the Kretschmann scalar. Also, as long as parameter $\alpha$ obeys certain conditions, the satisfaction of the weak energy condition is guaranteed by the collapsing configuration.Comment: 15 pages, 4 figures, to appear in GR