Extended hierarchical search (EHS) algorithm for detection of gravitational waves from inspiraling compact binaries

Pattern matching techniques like matched filtering will be used for online extraction of gravitational wave signals buried inside detector noise. This involves cross correlating the detector output with hundreds of thousands of templates spanning a multi-dimensional parameter space, which is very expensive computationally. A faster implementation algorithm was devised by Mohanty and Dhurandhar [1996] using a hierarchy of templates over the mass parameters, which speeded up the procedure by about 25 to 30 times. We show that a further reduction in computational cost is possible if we extend the hierarchy paradigm to an extra parameter, namely, the time of arrival of the signal. In the first stage, the chirp waveform is cut-off at a relatively low frequency allowing the data to be coarsely sampled leading to cost saving in performing the FFTs. This is possible because most of the signal power is at low frequencies, and therefore the advantage due to hierarchy over masses is not compromised. Results are obtained for spin-less templates up to the second post-Newtonian (2PN) order for a single detector with LIGO I noise power spectral density. We estimate that the gain in computational cost over a flat search is about 100.Comment: 6 pages, 6 EPS figures, uses CQG style iopart.cl

The Common Core State Standards\u27 Mathematical Practices: What do They Mean for the Adventist Mathematics Classroom?

A nationwide state-sponsored curriculum for mathematics and language arts will soon be implemented in public schools across the United States. This will also include a new system for assessing students’ mastery of the curriculum. The main focus of this article is what mathematics teachers will need to do to adapt their instruction because of the coming changes

A Histological Study Of Cleidodiscus Robustus Muller, 1934

Morphological description based on histological technique is a phase of parasitology which has been, in general, neglected. Almost all the previous authors, including the most recent ones such as Bychowsky (1957), Caballero, Blavo-Hollis and Orocott (1955), Chauhan (1953), Hargis (1959), Jain (I960), Llewellyn (1941), Meserve (19 37), Mizelle (193#, 1955), Price (1959), Ramalingam (1953), and Sproston (1946) have placed great emphasis on external morphology; particularly, on the cuticularized or sclerotized parts of the body such as haptoral anchors, clamp sclerites, copulatory apparatus, etc. These hard parts are, of course, of special value as systematic criteria. The internal anatomy, especially the genitalia, is also of great taxonomic value, although as pointed out by Brinkmann (1952) not much attention has been paid to them by the majority of helminthologists. Some authors, however, including Saint-Remy (1B90), Cerfontaine (1&95), Brinkmann (1942), Palombi (1943), and Yamaguti (1936), have endeavored to work out the details of the internal anatomy of some species. For the purpose of orientation, the taxonomical history and general morphology of the organism are given. The trematodes were named by Rudolphi in 1B0R, as an order, which included the following genera: Monostomata, Amphistomata , Pistoma and Polystomata. In l££5, van Beneden proposed the term, monogeneses, for trematodes which develope without metamorphosis and digeneses for those which develope with metamorphosis. The former category generally consisted of ectoparasites and the latter, exclusively, of endoparasites. In 1#63, Carus proposed the terms, Monogenea and Pigenea, respectively, to replace the two terms of van Beneden. In 1&92, Monticelli divided the order Trematoda into the suborders Heterocotylea, Aspidocotylea, and Malacotylea. The suborder Heterocotylea coincides with the Monogenea (Pratt, 1900). The Aspidocotylea and the Malacotylea are divisions of the Digenea. Odhner (1912) divided the Monogenea of Carus into the Polyopisthocotylea and Monopisthocotylea, respectively, on the basis of the presence or absence of a genito-intestinal canal. According to Fuhrmann (192$), the Monogenea and Digenea of Carus are accepted as orders and the order Trematoda Rudolphi, is elevated to the status of class. The order Monogenea Carus, as given by Fuhrmann, embraces three suborders, Monopisthodiscinea, Monoposthocotylinea, and Polyopisthocotylea. Price (1937) prefers the divisions Monopisthocotylea and Polyopisthocotylea of Odhner as suborders to those of Fuhrmann

Towards a Theory Grounded Theory of Language

In this paper, we build upon the idea of theory grounding and propose one specific form of theory grounding, a theory of language. Theory grounding is the idea that we can imbue our embodied artificially intelligent systems with theories by modeling the way humans, and specifically young children, develop skills with theories. Modeling theory development promises to increase the conceptual and behavioral flexibility of these systems. An example of theory development in children is the social understanding referred to as “theory of mind.” Language is a natural task for theory grounding because it is vital in symbolic skills and apparently necessary in developing theories. Word learning, and specifically developing a concept of words, is proposed as the first step in a theory grounded theory of language

A new HW Vir binary from the Palomar Transient Factory: PTF1 J072455.75+125300.3 - An eclipsing subdwarf B binary with a M-star companion

We report the discovery of an eclipsing binary -- PTF1 J072456$+$125301-- composed of a subdwarf B (sdB) star ($g'=17.2^m$) with a faint companion. Subdwarf B stars are core helium-burning stars, which can be found on the extreme horizontal branch. About half of them reside in close binary systems, but few are known to be eclipsing, for which fundamental stellar parameters can be derived.\newline We conducted an analysis of photometric data and spectra from the Palomar 60'' and the 200" Hale telescope respectively. A quantitative spectral analysis found an effective temperature of $T_{\text{eff}}=33900\pm350$\,K, log g = $5.74\pm0.08$ and log($n_{\text{He}}/n_{\text{H}}) = -2.02 \pm0.07$, typical for an sdB star. The companion does not contribute to the optical light of the system, except through a distinct reflection effect. From the light curve an orbital period of 0.09980(25)\,d and a system inclination of 83.56\pm0.30\,^{\circ} were derived. The radial velocity curve yielded an orbital semi-amplitude of K_1=95.8\pm 8.1\,\text{km s^{-1}}. The mass for the M-type dwarf companion is $0.155\pm0.020\,M_{\odot}$. PTF1\,J072456$+$125301 has similar atmospheric parameters to those of pulsating sdB stars (V346 Hya stars). Therefore it could be a high-priority object for asteroseismology, if pulsations were detected such as in the enigmatic case of NY Vir.Comment: Accepted to A&A, 7pages, 4 figure

On \u3cem\u3eK\u3c/em\u3e\u3cem\u3e\u3csub\u3es,t\u3c/sub\u3e\u3c/em\u3e-minors in Graphs with Given Average Degree

Let D(H) be the minimum d such that every graph G with average degree d has an H-minor. Myers and Thomason found good bounds on D(H) for almost all graphs H and proved that for \u27balanced\u27 H random graphs provide extremal examples and determine the extremal function. Examples of \u27unbalanced graphs\u27 are complete bipartite graphs Ks,t for a fixed s and large t. Myers proved upper bounds on D(Ks,t ) and made a conjecture on the order of magnitude of D(Ks,t ) for a fixed s and t → ∞. He also found exact values for D(K2,t) for an infinite series of t. In this paper, we confirm the conjecture of Myers and find asymptotically (in s) exact bounds on D(Ks,t ) for a fixed s and large t

Radio Pulse Properties of the Millisecond Pulsar PSR J0437-4715. I. Observations at 20cm

We present a total of 48 minutes of observations of the nearby, bright millisecond pulsar PSR J0437-4715 taken at the Parkes radio observatory in Australia. The data were obtained at a central radio frequency of 1380 MHz using a high-speed tape recorder that permitted coherent Nyquist sampling of 50 MHz of bandwidth in each of two polarizations. Using the high time resolution available from this voltage recording technique, we have studied a variety of single-pulse properties, most for the first time in a millisecond pulsar. We find no evidence for "diffractive" quantization effects in the individual pulse arrival times or amplitudes as have been reported for this pulsar at lower radio frequency using coarser time resolution (Ables et al. 1997). Overall, we find that the single pulse properties of PSR J0437-4715 are similar to those of the common slow-rotating pulsars, even though this pulsar's magnetosphere and surface magnetic field are several orders of magnitude smaller than those of the general population. The pulsar radio emission mechanism must therefore be insensitive to these fundamental neutron star properties.Comment: 24 Postscript pages, 11 eps figures. Accepted for publication in the Astrophysical Journal. Abbreviated abstract follow

Selective dispersal of avian rhombomere cells in orthotopic and heterotopic grafts

During hindbrain development, cells become segregated into segmental groups, rhombomeres, by mechanisms that are presently unknown. One contributory factor early in development may be an alternating periodicity in cell surface properties down the neuraxis. This possibility was previously suggested by experiments in which tissue from different segmental levels was apposed in the absence of a boundary. New boundaries were regenerated only when rhombomeres from adjacent positions or positions three rhombomeres distant from one another were apposed. Combinations of two odd-numbered or two even-numbered rhombomeres usually failed to generate a boundary. In order to pursue this phenomenon to the cellular level, we have used two approaches, both involving donor-to-host transplantation. First, quail rhombomeres were grafted at various hindbrain levels of a chick host. Apposition of rhombomere 4 (r4) with r3 was concomitant with negligible cell mixing across the interface. By contrast, combinations of r3 with r5 or with r3 tissue led to cell mixing that was more extensive in combinations of identical rhombomeres (r3 with r3) than between two alternate ones (r3 with r5). Secondly, we grafted small pieces of fluorescently prelabelled chick rhombomere tissue at various hindbrain levels of chick hosts. In most cases, cells dispersed widely when transplanted orthopically or two segments distant from that of their origin. Cells transplanted into an adjacent segment, however, showed a tendency to remain undispersed. Among the different graft combinations, furthermore, there was a variation in the extent of dispersal that showed an additional level of complexity not revealed in boundary regeneration experiments. The possibility is raised that the early partitioning of rhombomeres involves a hierarchy in the adhesive preferences of cell-cell interactions along the neuraxis

Higher Education Financial Assistance Tools for Middle- and Upper-Income Taxpayers

This article describes higher education financial assistance tools designed mainly for students of middle- and upper-income families who may not be eligible for financial aid from other sources. It includes the 2007 legislative updates for these tools, all of which have been devised and offered by either state or federal governments. The authors discuss the advantages and disadvantages of each tool and offer planning suggestions for families, students, and others who may participate in the higher education financial planning process

Materials Balance for Bromine, Chlorine, Sulfur, and Nitrogen in Europe

An understanding of the flow of toxic materials through industry and into the environment is one of the major tasks for the IIASA Study, "The Future Environments for Europe: Some Implications, of Alternative Development Paths". Toxic chemicals represent a great threat to the environment, and yet they are commonly used in industrial societies. A sustainable development path would require that usage and disposal of toxic chemicals be compatible with the long-term health of humans and the natural environment. Examining the current and past flows of these materials is a starting point for understanding options for management of their use and disposal, and the impact these options might have on the economy and society. The method chosen to analyze this problem is a materials balance approach in which toxic chemicals are traced as they move through the industrial economy; from extraction to production to intermediate uses and finally to end uses. The methodology and its advantages and disadvantages are discussed in some detail in Chapter 2. The implementation of this approach will become apparent in Chapters 3 through 6 as four individual chemical elements are studied. The four elements examined are bromine, chlorine, sulfur and nitrogen. These chemicals were chosen from a list of 15 which were of particular interest because of the exceptional biological activity of many of the compounds derived from them. The major goal of the project was to develop process-product flow diagrams for these elements showing their pathways through the industrial economy. Each of Chapters 3 through 6 contains a discussion of production processes, major uses, process-product flow diagram(s) and an Appendix with detailed information about the chemical transformations involved in each of the processes. In addition, further investigations including quantitative analysis and discussions of the applicability of this approach for a given element are included in some of the Chapters. Chapter 3, Bromine, presents a detailed qualitative material balance and a more aggregated quantitative material balance for the Netherlands and the United States for 1978 and 1985. The selection of these two countries was based solely on available data. Although the U.S. is not formally part of the study, it is useful as it more closely represents the Western European consumption pattern on average than the Netherlands. While the quantitative analysis focuses only on two countries for two years, it does demonstrate both the qualitative and quantitative aspects of the material balance approach. Bromine consumption is an interesting case as it has been heavily impacted by the phase-out of leaded gasoline and strong market shifts are expected in the future. Chapter 4, Chlorine, presents an in-depth qualitative materials balance and a look at the pathways of chlorine into the environment based on its pattern of end-use consumption. Currently, millions of tons of chlorine are produced each year for use as a disinfectant and in the organic and inorganic chemical industries. Many of the end-uses of chlorine result in eventual releases into the environment of various compounds which have a significant effect on environmental quality. Organic chlorine compounds are of great use to man because they are not readily biodegradable and they are chemically stable. However, because of these qualities they represent some of the most difficult disposal problems of any anthropogenic material. Chapter 5, Sulfur, presents a thorough qualitative analysis of the industrial processes and an in-depth discussion of the applicability of the materials balance approach to sulfur. A large portion of anthropogenically mobilized sulfur is from the burning of fossil fuels and the smelting of ores, two processes where sulfur is not an intentional product, simply an unavoidable one. The bulk of scientific study of sulfur wastes is concentrated on these areas due to their contribution to the acid rain problem. The analysis presented here shows that over half of the total anthropogenic sulfur budget in Europe is from industrial sources other than fossil fuels and ore smelting. This is a fairly surprising result. Thus, the flow of sulfur through the industrial economy in Europe is significant and greater understanding of the eventual disposal of this sulfur is needed. In addition, sulfuric acid is the number one industrial chemical based on the tonnage of production. It is used in a myriad of industries where it is generally consumed in the process and not embodied in the end product. This presents difficulties in the implementation of the materials balance analysis for sulfur. Chapter 6, Nitrogen, presents the process-product flow diagram for nitrogen. About 95% of the anthropogenically mobilized nitrogen is in the form of ammonia. Therefore, this chapter concentrates on the production and eventual end-uses of ammonia. While the process-product diagram is quite thorough, due to time constraints, further discussion and analysis of nitrogen is left as a future research topic. This report is the first step toward completing the task of understanding the impact of toxic materials in Europe. Future analysts may use the process-product diagrams and the analysis presented in this report as a starting point for a historical reconstruction which then could be used for building future scenarios of chemical flows of toxic materials