Weight-area trade-off study for a flat SNAP-8 radiator

Weight-area tradeoff evaluation of radiator used in SNAP-

Taming a non-convex landscape with dynamical long-range order: memcomputing Ising benchmarks

Recent work on quantum annealing has emphasized the role of collective behavior in solving optimization problems. By enabling transitions of clusters of variables, such solvers are able to navigate their state space and locate solutions more efficiently despite having only local connections between elements. However, collective behavior is not exclusive to quantum annealers, and classical solvers that display collective dynamics should also possess an advantage in navigating a non-convex landscape. Here, we give evidence that a benchmark derived from quantum annealing studies is solvable in polynomial time using digital memcomputing machines, which utilize a collection of dynamical components with memory to represent the structure of the underlying optimization problem. To illustrate the role of memory and clarify the structure of these solvers we propose a simple model of these machines that demonstrates the emergence of long-range order. This model, when applied to finding the ground state of the Ising frustrated-loop benchmarks, undergoes a transient phase of avalanches which can span the entire lattice and demonstrates a connection between long-range behavior and their probability of success. These results establish the advantages of computational approaches based on collective dynamics of continuous dynamical systems

Dependence receptor involvement in subtilisin-induced long-term depression and in long-term potentiation

The serine protease subtilisin induces a form of long-term depression (LTD) which is accompanied by a reduced expression of the axo-dendritic guidance molecule Unco-ordinated-5C (Unc-5C). One objective of the present work was to determine whether a loss of Unc-5C function contributed to subtilisin-induced LTD by using Unc-5C antibodies in combination with the pore-forming agents Triton X-100 (0.005%) or streptolysin O in rat hippocampal slices. In addition we have assessed the effect of subtilisin on the related dependence receptor Deleted in Colorectal Cancer (DCC) and used antibodies to this protein for functional studies. Field excitatory postsynaptic potentials (fEPSPs) were analysed in rat hippocampal slices and protein extracts were used for Western blotting. Subtilisin produced a greater loss of DCC than of Unc-5C, but the antibodies had no effect on resting excitability or fEPSPs and did not modify subtilisin-induced LTD. However, antibodies to DCC but not Unc-5C did reduce the amplitude of theta-burst long-term potentiation (LTP). In addition, two inhibitors of endocytosis – dynasore and tat-gluR2(3Y) – were tested and, although the former compound had no effect on neurophysiological responses, tat-gluR2(3Y) did reduce the amplitude of subtilisin-induced LTD without affecting the expression of DCC or Unc-5C but with some loss of PostSynaptic Density Protein-95. The results support the view that the dependence receptor DCC may be involved in LTP and suggest that the endocytotic removal of a membrane protein or proteins may contribute to subtilisin-induced LTD, although it appears that neither Unc-5C nor DCC are involved in this process. (220)

The Challenge of Preventing Teen Pregnancy in Texas

A reduction in teen pregnancy and subsequent reduction in teen births correlates to myriad improvements in personal (e.g., high school completion, experience of abuse and neglect, etc); social (e.g., number of children in single parent families, life-long poverty, incarceration rates, etc); and economic (e.g., Medicaid costs, decreased tax revenue, etc) outcomes. In 2005, over 73,000 teen girls in Texas age 15-19 became pregnant, a number significantly higher than any other state. Given the severity of the issue the formation of a statewide organization in Texas devoted to addressing the prevention of teen pregnancy is long overdue. The challenge of reducing teen pregnancy is daunting yet there is momentum and a cadre of committed individuals who have formally put together an organization to provide guidance, oversight and a statewide voice of leadership - all things needed to be successful reducing teen pregnancy in Texas. This commentary provides reactions to proposed strategies and to-date lessons learned

GPU accelerated risk quantification

Factor Analysis of Information Risk (FAIR) is a standard model for quantitatively estimating cybersecurity risks and has been implemented as a sequential Monte Carlo simulation in the RiskLens and FAIR-U applications. Monte Carlo simulations employ random sampling techniques to model certain systems through the course of many iterations. Due to their sequential nature, FAIR simulations in these applications are limited in the number of iterations they can perform in a reasonable amount of time. One method that has been extensively used to speed up Monte Carlo simulations is to implement them to take advantage of the massive parallelization available when using modern Graphics Processing Units (GPUs). Such parallelized simulations have been shown to produce significant speedups, in some cases up to 3,000 times faster then the sequential versions. Due to the FAIR simulation\u27s need for many samples from various beta distributions, three methods of generating these samples via inverse transform sampling on the GPU are investigated. One method calculates the inverse incomplete beta function directly, and the other two methods approximate this function - trading accuracy for improved parallelism. This method is then utilized in a GPU accelerated implementation of the FAIR simulation from RiskLens and FAIR-U using NVIDIA\u27s CUDA technology

Chemotherapy in bacillary dysentery: experience in the Edinburgh epidemic 1943-45

The results of the use of drugs of the sulphonamide group in the treatment of bacillary dysentery have bee extensively studied both in this country and in the United States; they have also been studied in the treatment of the disease in the forces in the Middle mast and other theatres of war.There are many factors which make it difficult to interpret the results of the use of any drug in the treatment of bacillary dysentery in Great Britain. First of all the disease, as seen in this country, is typically a very mild ones although cases of all grade of severity are encountered. Usually the illness lasts for only a few days, diarrhoea with loose stools containing, blood and mucus being the main symptom; but there are many cases which are só mild that only a few loose stools are passed, and there is the odd very severe case endangering life itself. It will therefor be difficult to demonstrate the effect of drugs in the very mild cases, as they will almost have recovered before any drug could take effect, and the presence of a large number of such cases in any series will mask the effect of the drug on the more severe cases; also it will be necessary to draw definite conclusions only from strictly controlled series of cases in any given outbreak, as by that means alone can allowance be made for the effect of varying severity of the disease in different epidemics. Further, it will be necessary to have a sufficiently large number of cases for study, so that there would be a chance of observing cases of 11 grades of severity. Then the different bacteriologica types of dysentery bacilli respond differently to sulphonamide treatment so that, if the results of treatment are to be of real value, all cases studied must be examined bacteriologically.The efficacy of the drugs in preventing the occurrence of, or reducing the number of convalescent carriers, and in rendering persistent carriers bacteriologically negative is of as much importance as, indeed is, in many cases, of more importance than, its effect on the clinical course of the disease. This can only be studied if adequate clearance tests are used, and if the cases are kept under observation for a sufficient length of time after treatment, so that the intermittent carrier will be detected, and also the case which relapses bacteriologically some time after treatment has been stopped. For this purpose it will also be necessary to see that chances of re- infection are reduced to a minimum and, once again, controls are really necessary as the convalescent carrier rate varies with different types of organism, in different epidemics and with the age -group to which the patients belong.The clinical features of the disease as seen in the United States, at least around New York, have been described recently by Hardy and Watt (1944) in a review of 1,500 cases. It would appear that the vast majority of the cases there are similar in severity to those in this country. They suggest the name "Shigellosis" for the disease as a great many of the cases never suffer from "dysentery" which, strictly speaking, means "blood and mucus in the stools ". Nevertheless, many of the cases described in American literature are of a severity rarely seen in this country.Manson -Bahr (1942) also points out that many cases of infection with dysentery bacilli never have blood and mucus in the stools even in countries where the disease is often vary severe. The published work on the treatment with sulphonamides of bacillary dysentery in the forces contains many.accounts of very severe cases, but also, in some the disease was very similar to that seen in this country. Scadding (1945), in, particular, describes treatment in an outbreak of relatively mild cases in the forces, and emphasises the difficulties of assessing the results of treatment in such cases.In Part I. of this thesis some of the literature recording the results of treatment of bacillary dysentery with sulphonamides is summarised and the conclusions which may be drawn from the published work are discussed.In Part II. the results of the treatment of 1000 cases with salts, sulphaguanidine or succinyl suiphathiazole at the City Hospital, Edinburgh are recorded and discussed, together with the results of blood sulphaguanidine and succinyl sulphathiazole estimations carried out on some of the cases. All of these cases were examined and observed by me while I was Senior Assistant at the hospital.The results obtained by myself together with those of others are discussed in Part III. and recommendations for the chemotherapy of the disease as seen in this country are made

Review of \u3ci\u3eDamselflies of Texas: A Field Guide.\u3c/i\u3e By John C. Abbott.

Well-produced field guides are always in demand, and Damselflies of Texas is one such. This compact, camera-bag-friendly compendium displays each of the 77 species known to occur, or that have been historically documented, in the state. The guide\u27s first 50 pages are introductory and full of useful detail. There follows a large section devoted to species descriptions and a set of appendices

Gamma ray production in paraffin by cosmic rays

Gamma ray production in paraffin by cosmic ray

Hard X‐ray polarimetry of solar flares with BATSE

We describe a technique for measuring the polarization of hard X‐rays from solar flares based on the angular distribution of that portion of the flux which is scattered off the top of the Earth’s atmosphere. The scattering cross section depends not only on the scatter angle itself, but on the orientation of the scatter angle with respect to the incident polarization vector. Consequently, the distribution of the observed albedo flux will depend on the direction and the polarization properties (i.e., the level of polarization and polarization angle) of the source. Since the albedo component can represent a relatively large fraction (up to 40%) of the direct source flux, there will generally be sufficient signal for making such a measurement. The sensitivity of this approach is therefore dictated by the effective area and the ability of a detector system to ‘image’ the albedo flux. The 4π coverage of the BATSE detectors on the Compton Gamma‐RayObservatory provides an opportunity to measure both the direct and the albedo flux from a given solar flare event. Although the BATSE design (with its large field‐of‐view for each detector) is not optimized for albedo polarimetry, we have nonetheless investigated the feasibility of this technique using BATSE data