Sub-100 attoseconds optics-to-microwave synchronization

We use two fiber-based femtosecond frequency combs and a low-noise carrier suppression phase detection system to characterize the optical to microwave synchronization achievable with such frequency divider systems. By applying specific noise reduction strategies, a residual phase noise as low as -120 dBc/Hz at 1 Hz offset frequency from a 11.55 GHz carrier is measured. The fractional frequency instability from a single optical-to-frequency divider is 1.1E-16 at 1 s averaging down to below 2E-19 after only 1000 s. The corresponding rms time deviation is lower than 100 attoseconds up to 1000 s averaging duration.Comment: 4 pages, 3 figure

Tanning bed use and melanoma: Establishing risk and improving prevention interventions

AbstractPurposeExposure to ultraviolet radiation (UVR) from indoor tanning devices is thought to cause melanoma and other negative health consequences. Despite these findings, the practice of indoor tanning in the United States remains prevalent. In this paper we aim to present a clear discussion of the relationship between indoor tanning and melanoma risk, and to identify potential strategies for effective melanoma prevention by addressing indoor tanning device use.Basic proceduresWe reviewed relevant literature on the risks of indoor tanning, current indoor tanning legislation, and trends in indoor tanning and melanoma incidence. Study was conducted at the University of Southern California, Los Angeles, CA between the years of 2014 and 2015.Main findingsOur findings reaffirm the relationship between indoor tanning and melanoma risk, and suggest a widespread public misunderstanding of the negative effects of indoor tanning.Principal conclusionsThis review argues for an aggressive initiative to reduce indoor tanning in the United States, to design prevention efforts tailored towards specific high risk groups, and the need to better inform the public of the risks of indoor tanning

From Design to Production Control Through the Integration of Engineering Data Management and Workflow Management Systems

At a time when many companies are under pressure to reduce "times-to-market" the management of product information from the early stages of design through assembly to manufacture and production has become increasingly important. Similarly in the construction of high energy physics devices the collection of (often evolving) engineering data is central to the subsequent physics analysis. Traditionally in industry design engineers have employed Engineering Data Management Systems (also called Product Data Management Systems) to coordinate and control access to documented versions of product designs. However, these systems provide control only at the collaborative design level and are seldom used beyond design. Workflow management systems, on the other hand, are employed in industry to coordinate and support the more complex and repeatable work processes of the production environment. Commercial workflow products cannot support the highly dynamic activities found both in the design stages of product development and in rapidly evolving workflow definitions. The integration of Product Data Management with Workflow Management can provide support for product development from initial CAD/CAM collaborative design through to the support and optimisation of production workflow activities. This paper investigates this integration and proposes a philosophy for the support of product data throughout the full development and production lifecycle and demonstrates its usefulness in the construction of CMS detectors.Comment: 18 pages, 13 figure

Perceived Red Tape and Precursors of Turnover: the Roles of Work Engagement and Career Adaptability

Drawing on job demands-resources theory, we propose that perceived red tape, as a hindrance job demand, triggers attitudinal and behavioral precursors of turnover in employees (turnover intentions and job search behaviors) by reducing their work engagement. In addition, we hypothesize that career adaptability, as a personal resource, buffers the detrimental effects of perceived red tape. In Study 1, three-wave data collected from employees (N = 202) working in Tanzanian public sector organizations supports the finding that work engagement mediates the effect of red tape on turnover intentions. Study 2 confirms this mediation, using data (N = 405) collected at three time points from a Chinese private organization, further verifying the mediating role of work engagement in the effect of red tape on job search behaviors. Supporting the moderating role of career adaptability, Study 2 also found that career adaptability attenuated the influence of red tape on work engagement and, subsequently, on turnover intentions and job search behaviors. Our article theoretically and empirically contributes to the understanding of how and when perceived red tape in organizations leads employees to consider leaving and prepare to leave

Specific heat of the quantum Bragg Glass

We study the thermodynamics of the vibrational modes of a lattice pinned by impurity disorder in the absence of topological defects (Bragg glass phase). Using a replica variational method we compute the specific heat $C_v$ in the quantum regime and find $C_v \propto T^3$ at low temperatures in dimension three and two. The prefactor is controlled by the pinning length. The non trivial cancellation of the linear term in $C_v$ arises from the so-called marginality condition and has important consequences for other mean field models.Comment: 5 pages, RevTex, strongly revised versio

RNA editing regulates insect gamma-aminobutyric acid receptor function and insecticide sensitivity

A-to-I pre-mRNA editing by adenosine deaminase enzymes has been reported to enhance protein diversity in the nervous system. In Drosophila, the resistance to dieldrin (RDL) gamma-aminobutyric acid (GABA) receptor subunit displays an editing site (R122) that is close to the putative GABA-binding site. We assessed the functional effects of editing at this site by expressing homomeric RDL receptors in Xenopus oocytes. After replacement of arginine 122 with a glycine, both agonist and fipronil potencies were shifted to the right in either fipronil-sensitive receptors or mutated resistant receptors (A301G/T350M). These data provide the first insight on the influence of RNA editing on GABA receptor function

Non-autonomous stochastic evolution equations and applications to stochastic partial differential equations

In this paper we study the following non-autonomous stochastic evolution equation on a UMD Banach space $E$ with type 2, {equation}\label{eq:SEab}\tag{SE} {{aligned} dU(t) & = (A(t)U(t) + F(t,U(t))) dt + B(t,U(t)) dW_H(t), \quad t\in [0,T], U(0) & = u_0. {aligned}. {equation} Here $(A(t))_{t\in [0,T]}$ are unbounded operators with domains $(D(A(t)))_{t\in [0,T]}$ which may be time dependent. We assume that $(A(t))_{t\in [0,T]}$ satisfies the conditions of Acquistapace and Terreni. The functions $F$ and $B$ are nonlinear functions defined on certain interpolation spaces and $u_0\in E$ is the initial value. $W_H$ is a cylindrical Brownian motion on a separable Hilbert space $H$. Under Lipschitz and linear growth conditions we show that there exists a unique mild solution of \eqref{eq:SEab}. Under assumptions on the interpolation spaces we extend the factorization method of Da Prato, Kwapie\'n, and Zabczyk, to obtain space-time regularity results for the solution $U$ of \eqref{eq:SEab}. For Hilbert spaces $E$ we obtain a maximal regularity result. The results improve several previous results from the literature. The theory is applied to a second order stochastic partial differential equation which has been studied by Sanz-Sol\'e and Vuillermot. This leads to several improvements of their result.Comment: Accepted for publication in Journal of Evolution Equation

Failure of the empirical OCT law in the Bi2Sr2CuO6+d compound

We have studied the evolution of the thermoelectric power S(T) with oxygen doping of single-layered Bi2Sr2CuO6+d thin films and ceramics in the overall superconducting (Tc, S290K) phase diagram. While the universal relation between the room-temperature thermopower S290K and the critical temperature is found to hold in the strongly overdoped region (d>0.14), a strong violation is observed in the underdoped part of the phase diagram. The observed behaviour is compared with other cuprates and the different scenarios are discussed.Comment: 7 pages, 5 figure