Almost Dark Galaxies: The Search for Optical Counterparts

Presented in this paper are results from neutral hydrogen (HI) imaging and analysis of the Almost Dark galaxies AGC 219533, AGC 227982, and AGC 268363 using new, higher resolution observations from the Very Large Array (VLA). Selected from the ALFALFA survey, Almost Dark galaxies possess significant HI reservoirs but, when the HI data is compared to survey-depth ground-based optical imaging, their optical stellar counterparts have extremely low surface brightnesses. AGC 219533 is one such object. The other two sources, AGC 227982 and AGC 26833, were candidate dark galaxies, as no stellar counterpart was identified in initial ALFALFA optical matching, and as such they possessed some of the most extreme levels of suppressed star formation amongst the isolated sources in the ALFALFA catalog. The new multiconfiguration, high angular (~20 ) and spectral (1.7 km/s) resolution HI observations presented here have produced spatially resolved column density and velocity distribution moment maps where the HI has been localized. HI masses are derived from VLA flux integral values and ALFALFA distance estimates, and are consistent with those derived from ALFALFA fluxes. Comparison of our resolved HI observations to Sloan Digitized Sky Survey (SDSS) optical images reveals previously unknown optical components for AGC 227982 and AGC 268363, and confirms the association with a very low surface brightness stellar counterpart for AGC 219533. These new results eliminate the three galaxies\u27 candidacy as dark galaxies

Cooperative behavior of qutrits with dipole-dipole interactions

We have identified a class of many body problems with analytic solution beyond the mean-field approximation. This is the case where each body can be considered as an element of an assembly of interacting particles that are translationally frozen multi-level quantum systems and that do not change significantly their initial quantum states during the evolution. In contrast, the entangled collective state of the assembly experiences an appreciable change. We apply this approach to interacting three-level systems.Comment: 5 pages, 3 figures. Minor correction

Summary statement of the Asilomar conference on recombinant DNA molecules

This meeting was organized to review scientific progress in research on recombinant DNA molecules and to discuss appropriate ways to deal with the potential biohazards of this work. Impressive scientific achievements have already been made in this field and these techniques have a remarkable potential for furthering our understanding of fundamental biochemical processes in pro- and eukaryotic cells. The use of recombinant DNA methodology promises to revolutionize the practice of molecular biology. Although there has as yet been no practical application of the new techniques, there is every reason to believe that they will have significant practical utility in the future

Shifting worlds: Leading educational *change in a quantum universe

The twentieth century theories of quantum physics and chaos theory in mathematics have had an impact across disciplines, but in many ways educational leaders have been trapped in the old Newtonian paradigm. The conceptual portion of this study bridges the paradigms to suggest new ways to view school leadership for the twenty-first century, using New Science constructs, systems thinking, and leadership concepts of business writers Senge (1990) and Wheatley (1992). It argues that such business models are appropriate for school organizations, and builds a conceptual model of a quantum principal who may participate in creating change through transformation (Burns, 1978) and revolution (Alinsky, 1946, 1971). The empirical portion of the dissertation compares the interaction of change, perceptions of change, and perceptions of the principals\u27 leadership in two New Hampshire high schools over the ten-year period from 1992--2002. One high school changed considerably; the other maintained status quo. Information on principals\u27 leadership styles was gathered by surveying the faculties at the schools one time in 2002, asking for their retrospective evaluations of their principals based on the model of leadership. Follow-up interviews were conducted with the five principals and with six teachers at each school, A leadership profile for each principal was developed from these data. The findings suggest that change within a school emerges from the interactions of the situation and the leadership styles of the principals. Four of the five principals interviewed were rated better than average in leadership by their faculties, yet good leadership skills and intent to change did not always result in changes. More systemic change happened in the more disorganized (chaotic) school. Change continued even under the leadership of the poorly-rated principal. This research suggests that effective leadership for change fosters risk-taking with an emphasis on creating a feeling of confidence and comfort in the process of change and motion, as well as building connection, communication, and capacity among all parts of the system. Processes, inter-relationships, and diverse people\u27s interacting energies create solutions. The New Science paradigm provides a powerful way to re-think the role of leadership in connection with change in schools

Beyond the Elliptic Genus

Given a Riemann surface and a riemannian manifold M with certain restrictions, we construct a cobordism invariant of M. This invariant is a generalization of the elliptic genus and it shares some similar properties

Ariel - Volume 10 Number 2

Executive Editors Madalyn Schaefgen David Reich Business Manager David Reich News Editors Medical College Edward Zurad CAHS John Guardiani World Mark Zwanger Features Editors Meg Trexler Jim O\u27Brien Editorials Editor Jeffrey Banyas Photography and Sports Editor Stuart Singer Commons Editor Brenda Peterso

Ariel - Volume 10 Number 6

Executive Editors Madalyn Schaefgen David Reich Business Manager David Reich News Editors Medical College Edward Zurad CAHS John Guardiani World Mark Zwanger Features Editors Meg Trexler Jim O\u27Brien Editorials Editor Jeffrey Banyas Photography and Sports Editor Stuart Singer Commons Editor Brenda Peterso

Superlubricity - a new perspective on an established paradigm

Superlubricity is a frictionless tribological state sometimes occurring in nanoscale material junctions. It is often associated with incommensurate surface lattice structures appearing at the interface. Here, by using the recently introduced registry index concept which quantifies the registry mismatch in layered materials, we prove the existence of a direct relation between interlayer commensurability and wearless friction in layered materials. We show that our simple and intuitive model is able to capture, down to fine details, the experimentally measured frictional behavior of a hexagonal graphene flake sliding on-top of the surface of graphite. We further predict that superlubricity is expected to occur in hexagonal boron nitride as well with tribological characteristics very similar to those observed for the graphitic system. The success of our method in predicting experimental results along with its exceptional computational efficiency opens the way for modeling large-scale material interfaces way beyond the reach of standard simulation techniques.Comment: 18 pages, 7 figure

Indigenous poultry production among rural households in Ogba/Egbema/Ndoni Local Government Area, Rivers State, Nigeria

The study examined indigenous poultry production among rural households in Ogba/Egbema/Ndoni Local Government Area, Rivers State, Nigeria. The objectives were to: describe the socio-economic characteristics of indigenous poultry farmers; determine the benefits of indigenous poultry production; determine the status of indigenous poultry production and identify factors affecting production of indigenous poultry in the study area. Data were collected with structured questionnaire from 108 randomly selected poultry farmers out of which 81 questionnaires were found useful. Data were analyzed with the use of frequency, percentage, mean scores and chi-square tests. Findings show that benefits derived by respondents from indigenous poultry production were: cost intensive (x̄ = 3.81), less cost feed (x̄ = 3.49), hardly sick (x̄ = 3.32), no disease problem (x̄ =141.5), no drugs needed (x̄ =3.37) and no vet needed (x̄ =3.76). The result of chi-square tests showed that, status vs. purpose of keeping poultry (0.66) and status vs. how much made (0.66) were significant at X2cal > X2tab. Factors affecting indigenous poultry production were: stealing (x̄ =3.54), lack of capital (x̄ =3.69), lack of information on price (x̄ =3.24), poor housing system (x̄ =3.51), poor management system (x̄ =3.51), lack of proper marketing structure for local birds (x̄ =3.061), predators (x̄ =3.86), price fluctuation (x̄ =3.45) and poor breeding stock (x̄ =3.37). The study recommends that since it has been confirmed that women dominate the production process, women’s access to production inputs and adequate care facilities should be improved. All forms of barriers against women should be discouraged especially when it comes to the area of production.Keywords: Indigenous Poultry Production, Rural Household