Evaluation of routines for numerical solution of the matrix equation AX + XA sup T + B = 0

Evaluation of routines for numerical solution of matrix equation for time-invariant linear system

Optical interface created by laser-cooled atoms trapped in the evanescent field surrounding an optical nanofiber

Trapping and optically interfacing laser-cooled neutral atoms is an essential requirement for their use in advanced quantum technologies. Here we simultaneously realize both of these tasks with cesium atoms interacting with a multi-color evanescent field surrounding an optical nanofiber. The atoms are localized in a one-dimensional optical lattice about 200 nm above the nanofiber surface and can be efficiently interrogated with a resonant light field sent through the nanofiber. Our technique opens the route towards the direct integration of laser-cooled atomic ensembles within fiber networks, an important prerequisite for large scale quantum communication schemes. Moreover, it is ideally suited to the realization of hybrid quantum systems that combine atoms with, e.g., solid state quantum devices

The Use of Open Communal Grazing Designs to Screen Options for Grazing Management

An open communal grazing design is described that enables a large number of grazing tactics to be concurrently evaluated in small plots under common grazing conditions. Pasture data indicated that the same level of utilisation occurred inside the experimental plots as in the surrounding field. However, differential grazing may occur where plots have divergent composition. The open communal design was economical using \u3c 5% of the land, livestock and fencing resources of alternative designs. The limitations of the open communal design as a research tool are also discussed

The Analysis of Results from Paired Paddock Comparisons

Paired-paddock comparisons are a common way of evaluating new grassland practices at a scale more relevant to farmers. They are also being used to replace or augment designed experiments and can be the only source of information available on a practice. However, it is often uncertain if the differences between paddocks are significant. Importantly, a current trend among funding organisations is to support paddock comparisons. The need for valid procedures to compare unreplicated treatments is increasingly urgent. It is suggested that a range of tools be used to infer statistical significance from using typical error values from related studies or subsampling, through to multivariate techniques to follow trends. Local ‘rules of thumb’ could be developed and data evaluated with calibrated models. A final judgement on treatment effects would need to be based upon the use of several criteria to achieve a ‘balance of probabilities’. Consideration of these problems suggests that paired-paddocks should only be used to evaluate contrasting treatments where large effects are expected and not small variations within a practice

Effects of cIAP-1, cIAP-2 and XIAP triple knockdown on prostate cancer cell susceptibility to apoptosis, cell survival and proliferation

<p>Abstract</p> <p>Background</p> <p>Manipulating apoptotic resistance represents an important strategy for the treatment of hormone refractory prostate cancer. We hypothesised that the Inhibitor of Apoptosis (IAP) Proteins may be mediating this resistance and knockdown of cIAP-1, cIAP-2 and XIAP would increase sensitivity to apoptosis.</p> <p>Methods</p> <p>cIAP-1, cIAP-2 and XIAP where knocked down either individually or in combination using siRNA in androgen independent prostate cancer PC-3 cells as confirmed by real-time PCR and western blotting. Cells were then treated with TRAIL, Etoposide, or Tunicamycin, and apoptosis assessed by PI DNA staining. Apoptosis was confirmed with Annexin V labelling and measurement of PARP cleavage, and was inhibited using the pan-caspase inhibitor, zVAD.fmk. Clonogenic assays and assessment of ID-1 expression by western blotting were used to measure recovery and proliferation.</p> <p>Results</p> <p>PC-3 are resistant to TRAIL induced apoptosis and have elevated expression of cIAP-1, cIAP-2 and XIAP. Combined knockdown sensitised PC-3 to TRAIL induced apoptosis, but not to Etoposide or Tunicmycin, with corresponding increases in caspase activity and PARP cleavage which was inhibited by ZVAD.fmk. Triple knock down decreased proliferation which was confirmed by decreased ID-1 expression.</p> <p>Conclusion</p> <p>Simultaneous knock down of the IAPs not only sensitised the PC-3 to TRAIL but also inhibited their proliferation rates and clonogenic survival. The inability to alter sensitivity to other triggers of apoptosis suggests that this effect is specific for death receptor pathways and knock down might facilitate immune-surveillance mechanisms to counter cancer progression and, in combination with therapeutic approaches using TRAIL, could represent an important treatment strategy.</p

Quantum Clock Synchronization Based on Shared Prior Entanglement

We demonstrate that two spatially separated parties (Alice and Bob) can utilize shared prior quantum entanglement, and classical communications, to establish a synchronized pair of atomic clocks. In contrast to classical synchronization schemes, the accuracy of our protocol is independent of Alice or Bob's knowledge of their relative locations or of the properties of the intervening medium.Comment: 4 page

Simulations of atomic trajectories near a dielectric surface

We present a semiclassical model of an atom moving in the evanescent field of a microtoroidal resonator. Atoms falling through whispering-gallery modes can achieve strong, coherent coupling with the cavity at distances of approximately 100 nanometers from the surface; in this regime, surface-induced Casmir-Polder level shifts become significant for atomic motion and detection. Atomic transit events detected in recent experiments are analyzed with our simulation, which is extended to consider atom trapping in the evanescent field of a microtoroid.Comment: 29 pages, 10 figure

High Reynolds-Number Assessment of a Multifractal Subgrid-Scale Model

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77107/1/AIAA-2002-2961-570.pd

Ending a decade of deception: a valiant failure, a not-so-valiant failure, and a success story

Prior studies involving two methods, Brooks Parsimony Analysis (BPA) and TreeMap, have found BPA to be the more reliable method. Recent criticisms leveled at these studies argue that the tests were unfairly created and biased in favor of BPA. The authors of a recent critique offered new exemplars to demonstrate flaws in BPA, plus a simple fix to correct the flaws found in TreeMap. A re-evaluation of their exemplars clearly shows that the authors' calculations are incorrect, their understanding of the methods is lacking, and that their simple fix does not work. Additional analyses using TreeMap 2.02 are run to show that TreeMap 2.02, like TreeMap 1.0, cannot adequately deal with widespread parasites, contrary to the claims of its supporters. Furthermore, the exemplars corroborate previous findings that BPA, when calculated correctly, is more reliable than TreeMap1.0 and TreeMap 2.02 and therefore the method of choice in coevolutionary and biogeographic studies.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75083/1/j.1096-0031.2003.00011.x.pd