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Mostrando recursos 1 - 20 de 144,716

1. Chapter 5. Evaporation and discharge dynamics of
highly charged two-component droplets generated by electrospray ionization We report studies of the Rayleigh discharge dynamics of charged two-component droplets consisting principally of methanol with either 2-methoxyethanol, tert-butanol, or m-nitrobenzyl alcohol. Phase Doppler anemometry (PDA) characterizes droplets generated by electrospray ionization according to size, velocity, and charge as they move through a uniform, linear electric field within an ion mobility cell. Repeated field reversals allow multiple PDA measurements of selected micron-sized droplets with up to 10 7 elementary positive charges. This “ping-pong ” technique generates individual droplet histories from which we ascertain solvent evaporation behavior and the dynamics of mass...

Application of stepped phosphoric acid digestion and carbonate clumped isotope thermometry to carbonates in carbonaceous chondrites ⎯ GRO 95577 (CR1), Orgueil (CI) and Tagish Lake (ungrouped C2) ⎯ indicates that aqueous alterations on carbonaceous chondrite parent bodies occurred from-31 to 65˚C from fluids with δ 18 OVSMOW values of-29.7 ‰ to 11.8 ‰ and δ 17 OVSMOW of-14.9 ‰ to 7.6‰. The estimated carbonate formation temperatures decrease in the order: calcite> dolomite> breunnerite. Based on independent constraints on the ages of these carbonates and models of the evolution of the oxygen isotope compositions of parent body waters, this trend indicates...

A survey of published data on self-fertilization in animals reveals that selffertility is widely distributed among invertebrate species. However, data to completely evaluate the role of self-fertilization in overall reproductive strategies is lacking for most self-compatible species. For the few better studied species, self-fertilization appears to be associated with dispersal distance. Although most interest in self-fertilization concerns detrimental effects on individuals and populations, benefits may occur under some circumstances. Selffertilization can ensure reproductive success when mates are unavailable or maintain gene combinations that have been successful. These circumstances should be more common to individuals with limited dispersal. To investigate the...

4. The author wishes to express his sincere appreciation - Oliveira Piva
to Professor Bradford Sturtevant for his guidance and very helpful suggestions throughout the experiments and during the analysis of the results. thankful to Professor Hans W. The author is also very Liepmann for his encourage-ment in the early part of the experimental work, when great difficulties were encountered. Professor Anatol Roshko deserves very special gratitude for his assistance with both academic and non-academic matters which made it possible for the author and his family to enjoy a much happier life in this country during the years of graduate work. It is a pleasure to thank Mrs. Geraldine Krentler for typing...

5. THE PLACE OF DIETARY PRACTICES IN THE LIVES OF OLDER WOMEN - Lisa Marie Curch; Lisa Marie Curch; Lexington Ky
Studies have supported the benefits of positive dietary behaviors in preventing or reducing morbidity and extending longevity, as well as the psychosocial function of dietary practices for quality of life. Research is needed though on the dietary behaviors of elders in general and older women in particular, for whom gender affects lifelong dietary patterns. Health behavior theory has typically focused on psychological factors, to the neglect of sociocultural processes. This investigation utilized a life course perspective, enhanced by social interactionist elements, to address aspects of development and change in behavior neglected by health behavior theories, such as temporal dimensions and...

6. Academic Anti-Semitism and the - Hansjoerg Klausinger; Hansjoerg Klausinger
The theme of academic anti-Semitism has been much discussed recently in histories of the interwar period of the University of Vienna, in particular its Faculty of Law and Policy Sciences. This paper complements these studies by focusing in this regard on the economics chairs at this faculty and, more generally, on the fate of the younger generation of the Austrian school of economics. After some introductory remarks the paper concentrates on three case studies: the neglect of Mises in all three appointments of economics chairs in the 1920s; the anti-Semitic overtones in the conflict between Hans Mayer and Othmar Spann,...

7. 8 th ASCE Specialty Conference on Probabilistic Mechanics and Structural Reliability PMC2000-159 SIMULATION OF BUFFETING RESPONSE HISTORY FOR LONG SPAN BRIDGES Abstract - Chunhua Liu; M. Asce; Haifan Xiang
Based on conventional buffeting theories, a methodology to simulate buffeting response histories for long bridges is presented in the study. On the basis of specific spectra, buffeting loads are simulated as spatially multi-correlated random processes. Self-excited loads are expressed in terms of convolution integrals between bridge deck motion and impulse response functions, in which unknown parameters are identified from wind tunnel test. Two examples are presented to illustrate calculated buffeting response histories. The presented method is verified by response spectra theory and wind tunnel test. This time domain approach can be employed as an implemental tool for buffeting analysis of...

8. hosted at - Krisztina Krempels; Ildikó Somlyai; Gábor Somlyai; Metastases From Lung Cancer; Krisztina Krempels; Ildikó Somlyai; Gábor Somlyai
Hypotheses. Because of the number of sufferers and high mortality rate, the standard care and new therapeutic options in the treatment of brain metastasis from lung cancer are the subject of intense research. A new concept based on the different chemical and physical behavior of protium and deuterium affecting cell signaling and tumor growth has been introduced in the treatment of cancer patients. The aim of this study was to investigate the impact of deuterium depleted water (DDW) consumption in addition to conventional forms of therapy on the survival of lung cancer patients with brain metastasis. Study design. A series...

9. Fertiliser-Derived Fluorine in Grazed Pasture Systems. - M. J. Hedley; P. Loganathan; N. D. Grace
Phosphorus (P) fertilisers, which are the main fertiliser input for the economic production of legume-based pastures, are the largest source of F enrichment for pastoral soils. Excessive levels of soil fluorine (F) can result in adverse effects for soil quality, livestock health and food safety. The majority of fertiliser F applied to pastures continues to accumulate in the biologically active topsoil due to strong adsorption to soil constituents. Fluorine adsorption in soils increases with increased contents of iron and aluminium oxides, layer silicates and allophane in soils and increased soil pH. In most pastoral soils with near-neutral pH, the majority...

combining evolutionary and cultural perspectives, focuses on emotions, sex, eating, violence, self-1 control, risk taking, and cooperation. Stigmata, wounds resembling those of Christ, have been reported since the 13th century. The wounds typically appear in association with visions following prolonged fasting. This paper argues that selfstarvation holds the key to understanding this unique event. Stigmata may result from selfmutilation occurring during dissociation, phenomena precipitated in part by dietary constriction. Psychophysiological mechanisms produced by natural selection adjust the salience of risk in light of current resource abundance. As a result, artificial dietary constriction results in indifference to harm. A variety of...

11. Language Research Bulletin, 23, ICU, Tokyo Chinese, French, German, Korean, Russian, and Spanish Enrollments (1990-2007): Language, Year, Re-enrollments, and Academic Field - Jean-pierre Bésiat; Timothy J. Riney
Although Japanese and English are the primary languages of instruction at ICU, what will in this paper be labeled “Other Languages ” have also been taught, and some for several decades: Chinese, French, German, Korean, Russian, and Spanish. This is the first paper to appear in the LRB since its inception in 1986 that has dealt with the Other Languages as a group. The focus here is on student enrollments in relation to four variables: (a) language (e.g., Korean vs. Russian), (b) year (e.g., 1990 vs. 2007), (c) academic division or field (e.g., Humanities vs. Education), and (d) re-enrollment (e.g.,...

12. Transition and Sequence Approaches to the Ownership Histories of the Largest - Balázs Vedres
* Many of this paper’s ideas were inspired by conversations with Peter Bearman, Laszlo Bruszt and

13. Harvard University - Swapna Reddy; Stuart Shieber
Abstract. Ideally designed software allow users to explore and experiment during their interaction, and to pursue multiple, interleaving plans. This makes it challenging to automatically recognize users ’ interactions with such software. This paper shows that this recognition problem can be formalized and solved using constraint satisfaction techniques. It constructs algorithms that use these techniques to recognize users ’ activities by comparing their interaction histories with a set of ideal solutions. These plan-recognition algorithms are complete, in the sense that they are guaranteed to recognize users ’ plans if they exist. We evaluate these algorithms empirically on data obtained from...

14. Corresponding author. - Tracey L. Greenwood; John D. Green; Brendan J. Hicks; M. Ann Chapman
Abstract The seasonal changes in the dynamics and life histories of the Cladocera in Lake Mangakaware, North Island, New Zealand, were studied over 19 months by sampling at weekly or 2-weekly intervals. Lake Mangakaware is a 13.3 ha polymictic lake with high nutrient status, low Secchi disc transparencies, and an unstable thermal regime. The four planktonic cladoceran species {Bosmina longirostris, B. meridionalis, Ceriodaphnia pulchella, and C. dubia) exhibited disjunct population maxima. Only B. longirostris was perennially present. All species exhibited low fecundities and low lipid content, indicating that food resources were limited and that competitive interactions and resistance to starvation...

15. Chronic Low-Level Mercury Exposure, BDNF Polymorphism, and Associations with Self-Reported Symptoms and Mood - James S. Woods
Recent reports have described neurobehavioral impairments in human subjects carrying a V66M polymorphism in the gene encoding brain-derived neurotrophic factor (BDNF). Inasmuch as ventral nervous system (CNS) deficits associated with this BDNF polymorphism are similar to those observed among subjects with chronic exposure to elemental mercury (Hg), we examined the potential effect of this BDNF polymorphism on symptoms and mood in an established cohort of dental practitioners with chronic lowlevel Hg exposure. Self-reported symptoms and mood were obtained by computerized questionnaire from 193 male dentists (DTs) and 230 female dental assistants (DAs). Spot urine samples were analyzed for mercury concentrations...

Landslide dams may form suddenly and unexpectedly, thereby posing hazards that must be rapidly assessed. In areas placed upstream, respect to the river dammed section, waters blocked by the dam may provoke floods spreading for kilometers, causing damages

17. Flame Investigation of Burning Titanium Powder - S. Kelzenberg; V. Weiser; E. Roth; O. Schulz; N. Eisenreich
Titanium is a metal included in igniters and pyrotechnic formulations because of its good ignitability and its complete burn-out which enable the full use of the high heat of reaction. In contrast to aluminium and boron, its burning behaviour has been investigated so far but the results are not conclusive. In this paper, the burning of titanium powder as bulk material in 1-gram scale was studied in an oxygen flow inside a window bomb. High-speed macro movies recorded the visual flame structure as well as moving and burning particles with 5000 fps. Timeresolved spectroscopy was applied to identify Ti-lines and...

18. Michty me, whit are ye gassin ’ aboot? The use of Scots in the newspaper comic strips The Broons and Oor Wullie - Haavet Bjørnson
Skotsk har lang historie som skriftspråk. Før Skottland og England ble forent under en konge ble det skrevet ekstensivt på skotsk, men da unionen ble et faktum begynte de fleste som kunne skrive å rette seg sørover med henhold til skriftspråket. Resultatet var at det skotske skriftspråket forsvant, med unntak av fra poesien, der det fortsatt sto sterkt. I dag er det flere og flere skotske forfattere som skriver på skotsk. Dessverre sliter de

This presentation is intended to provide background on the principles involved in geotechnical and infrastructure applications of Time Domain Reflectometry (TDR). TDR is basically radar in which a voltage pulse is launched along a coaxial cable. A reflection of the voltage pulse occurs at every location where the cable is being deformed and each location is distinguished by the reflection travel time. For example, localized shear in a rock or soil mass will deform a cable grouted into a borehole and the TDR reflection magnitude is proportional to the magnitude of cable deformation. In one variation of this principle, a...

20. $rec.titulo - E. A. $ammel; E. Ingebritsen; R. H. Mariner
Results of recent geological and geophysical studies at Newberry Volcano have been incorporated into conceptual and numerical models of a magma-based hydrothermal system. Numerical simulations begin with emplacement of a small magma body, the presumed source of silicic eruptions at Newberry that began about 10,000 B.P., into a thermal regime representing 100,000 years of cooling of a large underlying intrusion. Simulated flow patterns and thermal histories for three sets of hypothetical permeability values are compatible with data from four geothermal drill holes on the volcano. Meteoric recharge cools the caldera-fill deposits, but thermal water moving up a central conduit representing...

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