Overexpression of hedgehog signaling is associated with epidermal tumor formation in vitamin D receptor-null mice.

The vitamin D receptor (VDR) ligand, 1,25 dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), reduces proliferation and enhances differentiation, and thus has been investigated for a role in preventing or treating cancer. Mice deficient for the VDR display a hyperproliferative response in the hair follicle and epidermis and decreased epidermal differentiation. Unlike their wild-type littermates, when treated with 7,12 dimethylbenzanthracene (DMBA) or UVB, they develop skin tumors, including some characteristic of overexpression of the hedgehog (Hh) pathway. Both the epidermis and utricles of the VDR-null animals overexpress elements of the Hh pathway (sonic hedgehog (Shh) 2.02-fold, patched1 1.58-fold, smoothened 3.54-fold, glioma-associated oncogene homolog (Gli)1 1.17-fold, and Gli2 1.66-fold). This overexpression occurs at an age (11 weeks) at which epidermal hyperproliferation is most visible and is spatially controlled in the epidermis. DMBA- or UVB-induced tumors in the VDR-null mice also overexpress elements of this pathway. Moreover, 1,25(OH)(2)D(3) downregulates the expression of some members of the Hh pathway in an epidermal explants culture system, suggesting a direct regulation by 1,25(OH)(2)D(3). Our results suggest that increased expression of Shh in the keratinocytes of the VDR-null animal activates the Hh pathway, predisposing the skin to the development of both malignant and benign epidermal neoplasms

Case of “Slow” Stroke from Carotid Artery Occlusion Treated by Delayed but Cautious Endovascular Intervention

In a challenging case of carotid occlusion with slowly evolving stroke, we used brain imaging to facilitate endovascular revascularization resulting in the relief of the patient's symptoms. Patients with carotid occlusion and continued neurological worsening or fluctuations present enormous treatment challenges. These patients may present “slow” strokes with subacute infarcts that present significant challenges and risks during attempts at revascularization of the occluded artery. We present such a case in which we used multimodal imaging techniques, including MR-perfusion, to facilitate endovascular revascularization. Our approach of delayed but cautious intra-arterial thrombolytic therapy, guided by brain imaging, and followed by stent placement across the residual stenosis, enabled revascularization of the occluded artery without overt in-hospital complications

Longitude : a privacy-preserving location sharing protocol for mobile applications

Location sharing services are becoming increasingly popular. Although many location sharing services allow users to set up privacy policies to control who can access their location, the use made by service providers remains a source of concern. Ideally, location sharing providers and middleware should not be able to access users’ location data without their consent. In this paper, we propose a new location sharing protocol called Longitude that eases privacy concerns by making it possible to share a user’s location data blindly and allowing the user to control who can access her location, when and to what degree of precision. The underlying cryptographic algorithms are designed for GPS-enabled mobile phones. We describe and evaluate our implementation for the Nexus One Android mobile phone

Secure Proximity-Based Identity Pairing using an Untrusted Signalling Service

New protocols such as WebRTC promise seamless in-browser peer-to-peer communications that in theory remove the need for third-party services. In practice, widespread use of Firewalls, NATS and dynamic IP addresses mean that overlay addressing or use of some fixed rendezvous point is still needed. In this paper we describe a proximity-based pairing scheme that uses a signalling service to minimise the trust requirements on the third party, achieving anonymity and avoiding the need for PKI, while still requiring only a simple asymmetric pairing protocol

Coupling of Electronic and Motional Dynamics in a Cold Atom Optical Lattice

We study the coupling of internal electronic excitations to vibrational modes of the external motion of ultracold atoms in an optical lattice. For different ground and excited state potentials the on-site coupling of excitations and vibrations term renormalizes the effective electronic transition energy, which appears e.g. in clock transitions. In addition in the Mott state with filling factor one, the dipole-dipole coupling between neighbouring sites includes emission and absorption of vibrational quanta. Such processes create a significant mechanism for excitation of vibrations leading to motional heating of the lattice atoms by resonant light interaction. We calculate estimates of the corresponding parameters from a perturbation expansion in small atomic displacements.Comment: 4 pages, 5 figure

Muscle strengthening intervention for boys with haemophilia: Developing and evaluating a best-practice exercise programme with boys, families and health-care professionals

Background: Muscle strengthening exercises have the potential to improve outcomes for boys with haemophilia, but it is unclear what types of exercise might be of benefit. We elicited the views of health-care professionals, boys and their families to create and assess a home-based muscle strengthening programme. Objective: To design and develop a muscle strengthening programme with healthcare professionals aimed at improving musculoskeletal health, and refine the intervention by engaging boys with haemophilia and their families (Study 1). Following delivery, qualitatively evaluate the feasibility and acceptability of the exercise programme with the boys and the study's physiotherapists (Study 2). Design: A person-based approach was used for planning and designing the exercise programme, and evaluating it post-delivery. The following methods were utilized: modified nominal group technique (NGT) with health-care professionals; focus group with families; exit interviews with boys; and interviews with the study's physiotherapists. Results: Themes identified to design and develop the intervention included exercises to lower limb and foot, dosage, age accommodating, location, supervision and monitoring and incentivization. Programme refinements were carried out following engagement with the boys and families who commented on: dosage, location, supervision and incentivization. Following delivery, the boys and physiotherapists commented on progression and adaptation, physiotherapist contact, goal-setting, creating routines and identifying suitable timeframes, and a repeated theme of incentivization. Conclusions: An exercise intervention was designed and refined through engagement with boys and their families. Boys and physiotherapists involved in the intervention's delivery were consulted who found the exercises to be generally acceptable with some minor refinements necessary

Collective Light Emission of a Finite Size Atomic Chain

Radiative properties of collective electronic states in a one dimensional atomic chain are investigated. Radiative corrections are included with emphasize put on the effect of the chain size through the dependence on both the number of atoms and the lattice constant. The damping rates of collective states are calculated in considering radiative effects for different values of the lattice constant relative to the atomic transition wave length. Especially the symmetric state damping rate as a function of the number of the atoms is derived. The emission pattern off a finite linear chain is also presented. The results can be adopted for any chain of active material, e.g., a chain of semiconductor quantum dots or organic molecules on a linear matrix.Comment: 10 pages, 20 figure

THE INFLUENCE OF RESIN MODIFIERS ON THE PERFORMANCE OF HOT MIX ASPHALT

ABSTRACT In order to study the influence of resin modifiers materials on the performance of hot mix asphalts (HMA), two types of resin modifiers were selected. One was anUnsaturated Polyester Resin (UPR) and the other was an Epoxy Resin (ER). Also, unsaturated polyester resin mixed with 3% epoxy resin (UPRER) was used according to test results, which gave preference to 3% additions. Marshal test was conducted to study the stability, flow, bulk density, air voids (AV), voids in mineral aggregate (VMA) and voids filled with bitumen (VFA) for controlled hot asphalt mixtures and resin: modified mixtures at various resin modifiers contents. A computer program named BISAR was also used to determine the total stress, strain and displacement in x-y, and z-direction for flexible pavements constructed with these hot mix asphalts modified with resin additives.Experimental results showed that all resin-modified asphalt mixtures have higher flow, bulk density and VFA compared with control mixture. The stability of asphalt mixtures with UPPER was always higher than the control mixture. Unlike, for type ER and UPR the stability was lower than the control mixture up to 1% and 2% respectively then they increase. The UPRER gave higher stability, flow, AV and VMA than the other types. Moreover, the UPR gave the highest value of bulk density and VFA. The maximum stability occurs at 3% resin modifiers content for all types. The total stress and strain relatively increase with the increase of mix depth till 10 cm, then they decrease for all types of resin modifiers. The maximum total stresses and strain in case of UPRER are higher values than those achieved by ER and UPR respectively. The total displacement in case of UPRER is higher than that achieved by ER and UPR respectively. As resin modifiers can improve the field performance of asphalt mixes comprehensively, they will be of great benefit to the engineering field

Hybrid Quantum System of a Nanofiber Mode Coupled to Two Chains of Optically Trapped Atoms

A tapered optical nanofiber simultaneously used to trap and optically interface of cold atoms through evanescent fields constitutes a new and well controllable hybrid quantum system. The atoms are trapped in two parallel 1D optical lattices generated by suitable far blue and red detuned evanescent field modes very close to opposite sides of the nanofiber surface. Collective electronic excitations (excitons) of each of the optical lattices are resonantly coupled to the second lattice forming symmetric and antisymmetric common excitons. In contrast to the inverse cube dependence of the individual atomic dipole-dipole interaction, we analytically find an exponentially decaying coupling strength with distance between the lattices. The resulting symmetric (bright) excitons strongly interact with the resonant nanofiber photons to form fiber polaritons, which can be observed through linear optical spectra. For large enough wave vectors the polariton decay rate to free space is strongly reduced, which should render this system ideal for the realization of long range quantum communication between atomic ensembles.Comment: 9 pages, 9 figure