An integrated source of broadband quadrature squeezed light

An integrated silicon nitride resonator is proposed as an ultra-compact source of bright single-mode quadrature squeezed light at 850 nm. Optical properties of the device are investigated and tailored through numerical simulations, with particular attention paid to loss associated with interfacing the device. An asymmetric double layer stack waveguide geometry with inverse vertical tapers is proposed for efficient and robust fibre-chip coupling, yielding a simulated total loss of -0.75 dB/facet. We assess the feasibility of the device through a full quantum noise analysis and derive the output squeezing spectrum for intra-cavity pump self-phase modulation. Subject to standard material loss and detection efficiencies, we find that the device holds promises for generating substantial quantum noise squeezing over a bandwidth exceeding 1 GHz. In the low-propagation loss regime, approximately -7 dB squeezing is predicted for a pump power of only 50 mW.Comment: 23 pages, 12 figure

An experimental study of the buckling of complete spherical shells

Buckling of complete spherical shells to examine Tsien energy hypothesi

TGF-β signaling links E-cadherin loss to suppression of nucleotide excision repair.

E-cadherin is a cell adhesion molecule best known for its function in suppressing tumor progression and metastasis. Here we show that E-cadherin promotes nucleotide excision repair through positively regulating the expression of xeroderma pigmentosum complementation group C (XPC) and DNA damage-binding protein 1 (DDB1). Loss of E-cadherin activates the E2F4 and p130/107 transcription repressor complexes to suppress the transcription of both XPC and DDB1 through activating the transforming growth factor-β (TGF-β) pathway. Adding XPC or DDB1, or inhibiting the TGF-β pathway, increases the repair of ultraviolet (UV)-induced DNA damage in E-cadherin-inhibited cells. In the mouse skin and skin tumors, UVB radiation downregulates E-cadherin. In sun-associated premalignant and malignant skin neoplasia, E-cadherin is downregulated in association with reduced XPC and DDB1 levels. These findings demonstrate a crucial role of E-cadherin in efficient DNA repair of UV-induced DNA damage, identify a new link between epithelial adhesion and DNA repair and suggest a mechanistic link of early E-cadherin loss in tumor initiation

Opening the Pandora's box of quantum spinor fields

Lounesto's classification of spinors is a comprehensive and exhaustive algorithm that, based on the bilinears covariants, discloses the possibility of a large variety of spinors, comprising regular and singular spinors and their unexpected applications in physics and including the cases of Dirac, Weyl, and Majorana as very particular spinor fields. In this paper we pose the problem of an analogous classification in the framework of second quantization. We first discuss in general the nature of the problem. Then we start the analysis of two basic bilinear covariants, the scalar and pseudoscalar, in the second quantized setup, with expressions applicable to the quantum field theory extended to all types of spinors. One can see that an ampler set of possibilities opens up with respect to the classical case. A quantum reconstruction algorithm is also proposed. The Feynman propagator is extended for spinors in all classes.Comment: 18 page

Effective action for a quantum scalar field in warped spaces

We investigate the one-loop corrections at zero, as well as finite temperature, of a scalar field taking place in a braneworld motived warped background. After to reach a well defined problem, we calculate the effective action with the corresponding quantum corrections to each case.Comment: 10 pages, to appear in The European Physical Journal

Ecosystem Services of Prairie Wolf Slough: Quantifying Carbon Storage

This project is a case study of the benefits of a natural area in Highland Park, Illinois, Prairie Wolf Slough (PWS). A series of experiments were set up to quantify the carbon storage potential of PWS. The results presented here provide an estimate of the aboveground biomass in the forest of PWS with a preliminary estimate of the stored carbon’s value. This is done using the social cost of carbon. It was found that species carbon storage differed based on the number of individuals for each species and their physical size. In addition, using the 2015 discount rate of 3%, which is $12, the forest at PWS would be worth$15,588.99 for standing carbon. Using the discount rate of 5%, which is $36, the forest at PWS would be worth$50,664.21 for standing carbon. Without the assignment of a monetary value on terrestrial natural capital, and any ecosystem service for that matter, the default value is zero and/or unrecognized, and, consequently, exploited. This de facto exclusion of the natural world’s value in decision making has led to a call to value the services provided by nature, as is the goal and expected contribution of this paper

Sedimentary Depositional Cyclicity, Mission Canyon and Charles Formations (Mississippian), Williston Basin, North Dakota

Workers within the Williston Basin have repeatedly reported the presence of sedimentary cyclicity within the carbonate and evaporite succession of the Mississippian Madison Group. Descriptions of cyclicity are diverse and commonly conflict. Previous work has been exclusively qualitative. This study used a group of statistical techniques in a method designed specifically for the objective identification and evaluation of cyclicity in the lithofacies sequence of the Mission Canyon and lower Charles Formations in North Dakota. Twelve cores were sampled at every visually distinguishable lithologic unit. Forty-six lithologic components were counted in each sample on a presence-absence basis. The phi association coefficient was used to calculate similarities between all pairs of lithologic units in a data set. Similarities were clustered; significant clusters were used as lithofacies. The succession of lithofacies was examined for cyclicity using embedded Markov analysis. Mutual substitutability analysis identified pairs of lithofacies that could be combined to permit further iteration of cyclicity analysis. The final succession was examined using entropy analysis. A variety of carbonate and evaporite lithofacies, deposited under subtidal to supratidal, open- and restricted-circulation conditions, were identified. Specific interpretation of depositional environments was rarely permitted by the data. Both lithofacies and cyclicity reflect increased evaporite deposition upward in the succession and from the basin center to the margin. After analysis of data sets from individual wells, data representing selected stratigraphic intervals over larger geographic areas were combined and examined for cyclicity. Homogeneity tests of the combined data sets indicate probable areal stationarity within the succession, although the occurrence of abrupt cyclicity changes in the succession indicates a lack of vertical stationarity. Cyclicity exists in the succession but is not everywhere present, nor uniform in character throughout the basin. Cycles are simple, dominantly asymmetric, and of minor importance on the flanks of the basin; they are more complex, dominantly symmetric, and dominate the succession near the basin center. The cyclicity is more compatible with deposition of lithofacies as a mosaic, than as narrow facies belts, and indicates the need for new facies models

Straight spinning cosmic strings in Brans-Dicke gravity

It is presented an exact solution of straight spinning cosmic strings in Brans-Dicke theory of gravitation. The possibility of the existence of closed timelike curves around these cosmic strings is analyzed. Furthermore, the stability about the formation of the topological defect discussed here is checked. It is shown the existence of a suitable choice for the integration constants in which closed timelike curves are not allowed. We also verify if it is possible that the obtained spacetime can be the source that describes the observed rotational curves in some galaxies.Comment: 13 pages, 1 figur