1,739 research outputs found

    67/09/27 Brief of American Civil Liberties Union, American Civil Liberties Union of Ohio, and New York Civil Liberties Union, Amici Curiae

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    The American Civil Liberties Union (ACLU), ACLU of New York and New York Civil Liberties Union\u27s Amici Curiae Brief arguing against the stop-and-frisk practice as seen in Terry v. Ohio and Chilton v. Ohio, Peters v. New York, and Sibron v. New York

    67/09/27 Brief of American Civil Liberties Union, American Civil Liberties Union of Ohio, and New York Civil Liberties Union, Amici Curiae

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    The American Civil Liberties Union (ACLU), ACLU of New York and New York Civil Liberties Union\u27s Amici Curiae Brief arguing against the stop-and-frisk practice as seen in Terry v. Ohio and Chilton v. Ohio, Peters v. New York, and Sibron v. New York

    Changes in growth of tropical forests: evaluating potential biases

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    Over the past century almost every ecosystem on Earth has come under the influence of changes in atmospheric composition and climate caused by human activity. Tropical forests are among the most productive and extensive ecosystems, and it has been hypothesized that both the dynamics and biomass of apparently undisturbed, old-growth tropical forests have been changing in response to atmospheric changes. Long-term forest sample plots are a critical tool in detecting and monitoring such changes, and our recent analysis of pan-tropical-forest plot data has suggested that the biomass of tropical forests has been increasing, providing a modest negative feedback on the rate of accumulation of atmospheric CO2. However, it has been argued that some of these old forest plot data sets have significant problems in interpretation because of the use of nonstandardized methodologies. In this paper we examine the extent to which potential field methodological errors may bias estimates of total biomass change by detailed examination of tree-by-tree records from up to 120 Neotropical plots to test predictions from theory. Potential positive biases on measurements of biomass change include a bias in site selection, tree deformities introduced by the measurement process, poor methodologies to deal with tree deformities or buttresses, and nonrecording of negative growth increments. We show that, while it is important to improve and standardize methodologies in current and future forest-plot work, any systematic errors introduced by currently identified biases in past studies are small and calculable. We conclude that most tropical-forest plot data are of useful quality, and that the evidence does still weigh conclusively in favor of a recent increase of biomass in old-growth tropical forests

    Large Scale Traces of Solar System Cold Dust on CMB Anisotropies

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    We explore the microwave anisotropies at large angular scales produced by the emission from cold and large dust grains, expected to exist in the outer parts of the Solar System, using a simple toy model for this diuse emission. Its amplitude is constrained in the Far-IR by the COBE data and is compatible with simulations found in the literature. We analyze the templates derived after subtracting our model from the WMAP ILC 7 yr maps and investigate on the cosmological implications of such a possible foreground. The anomalies related to the low quadrupole of the angular power spectrum, the two-point correlation function, the parity and the excess of signal found in the ecliptic plane are significantly alleviated. An impact of this foreground for some cosmological parameters characterizing the spectrum of primordial density perturbations, relevant for on-going and future CMB anisotropy experiments, is found.Comment: Issue 2.0, Accepted for pub. in MNRAS, Apr 8th, 2011, (sub. Oct 4th, 2010); 10 pages, 6 Figures, 1 table; pdflatex with mn2e, AMS, natbib, txfonts, graphic

    Interaction between dark energy and dark matter: observational constraints from OHD, BAO, CMB and SNe Ia

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    In order to test if there is energy transfer between dark energy and dark matter, we investigate cosmological constraints on two forms of nontrivial interaction between the dark matter sector and the sector responsible for the acceleration of the universe, in light of the newly revised observations including OHD, CMB, BAO and SNe Ia. More precisely, we find the same tendencies for both phenomenological forms of the interaction term Q=3γHρQ=3\gamma H\rho, i.e., the parameter γ\gamma to be a small number, γ102|\gamma|\approx 10^{-2}. However, concerning the sign of the interaction parameter, we observe that γ>0\gamma>0 when the interaction between dark sectors is proportional to the energy density of dust matter, whereas the negative coupling (γ<0\gamma<0) is preferred by observations when the interaction term is proportional to dark energy density. We further discuss two possible explanations to this incompatibility and apply a quantitative criteria to judge the severity of the coincidence problem. Results suggest that the γm\gamma_mIDE model with a positive coupling may alleviate the coincidence problem, since its coincidence index CC is smaller than that for the γd\gamma_dIDE model, the interacting quintessence and phantom models by four orders of magnitude.Comment: 16 pages, 5 figure

    Hamiltonian dynamics and constrained variational calculus: continuous and discrete settings

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    The aim of this paper is to study the relationship between Hamiltonian dynamics and constrained variational calculus. We describe both using the notion of Lagrangian submanifolds of convenient symplectic manifolds and using the so-called Tulczyjew's triples. The results are also extended to the case of discrete dynamics and nonholonomic mechanics. Interesting applications to geometrical integration of Hamiltonian systems are obtained.Comment: 33 page

    Infants’ behavioral and physiological profile and mother–infant interaction

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    This study aims to (a) identify and profile groups of infants according to their behavioral and physiological characteristics, considering their neurobehavioral organization, social withdrawal behavior, and endocrine reactivity to stress, and to (b) analyze group differences in the quality of mother–infant interaction. Ninety seven 8-week-old infants were examined using the Neonatal Behavioral Assessment Scale and the Alarm Distress Baby Scale. Cortisol levels were measured both before and after routine inoculation between 8 and 12 weeks. At 12 to 16 weeks mother–infant interaction was assessed using the Global Rating Scales of Mother–Infant Interaction. Three groups of infants were identified: (a) ‘‘withdrawn’’; (b) ‘‘extroverted’’; (c) ‘‘underaroused.’’ Differences between them were found regarding both infant and mother behaviors in the interaction and the overall quality of mother–infant interaction. The identification of behavioral and physiological profiles in infants is an important step in the study of developmental pathways

    Ubx Regulates Differential Enlargement and Diversification of Insect Hind Legs

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    Differential enlargement of hind (T3) legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s) responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug) and Acheta domesticus (house cricket). In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx) is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs

    Deficient expression of DNA repair enzymes in early progression to sporadic colon cancer

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    BACKGROUND:Cancers often arise within an area of cells (e.g. an epithelial patch) that is predisposed to the development of cancer, i.e. a "field of cancerization" or "field defect." Sporadic colon cancer is characterized by an elevated mutation rate and genomic instability. If a field defect were deficient in DNA repair, DNA damages would tend to escape repair and give rise to carcinogenic mutations.PURPOSE:To determine whether reduced expression of DNA repair proteins Pms2, Ercc1 and Xpf (pairing partner of Ercc1) are early steps in progression to colon cancer.RESULTS:Tissue biopsies were taken during colonoscopies of 77 patients at 4 different risk levels for colon cancer, including 19 patients who had never had colonic neoplasia (who served as controls). In addition, 158 tissue samples were taken from tissues near or within colon cancers removed by resection and 16 tissue samples were taken near tubulovillous adenomas (TVAs) removed by resection. 568 triplicate tissue sections (a total of 1,704 tissue sections) from these tissue samples were evaluated by immunohistochemistry for 4 DNA repair proteins. Substantially reduced protein expression of Pms2, Ercc1 and Xpf occurred in field defects of up to 10 cm longitudinally distant from colon cancers or TVAs and within colon cancers. Expression of another DNA repair protein, Ku86, was infrequently reduced in these areas. When Pms2, Ercc1 or Xpf were reduced in protein expression, then either one or both of the other two proteins most often had reduced protein expression as well. The mean inner colon circumferences, from 32 resections, of the ascending, transverse and descending/sigmoid areas were measured as 6.6 cm, 5.8 cm and 6.3 cm, respectively. When combined with other measurements in the literature, this indicates the approximate mean number of colonic crypts in humans is 10 million.CONCLUSIONS:The substantial deficiencies in protein expression of DNA repair proteins Pms2, Ercc1 and Xpf in about 1 million crypts near cancers and TVAs suggests that the tumors arose in field defects that were deficient in DNA repair and that deficiencies in Pms2, Ercc1 and Xpf are early steps, often occurring together, in progression to colon cancer.This item is part of the UA Faculty Publications collection. For more information this item or other items in the UA Campus Repository, contact the University of Arizona Libraries at [email protected]

    The type IIb SN 2008ax: spectral and light curve evolution

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    We present spectroscopy and photometry of the He-rich supernova (SN) 2008ax. The early-time spectra show prominent P-Cygni H lines, which decrease with time and disappear completely about two months after the explosion. In the same period He I lines become the most prominent spectral features. SN 2008ax displays the ordinary spectral evolution of a type IIb supernova. A stringent pre-discovery limit constrains the time of the shock breakout of SN 2008ax to within only a few hours. Its light curve, which peaks in the B band about 20 days after the explosion, strongly resembles that of other He-rich core-collapse supernovae. The observed evolution of SN 2008ax is consistent with the explosion of a young Wolf-Rayet (of WNL type) star, which had retained a thin, low-mass shell of its original H envelope. The overall characteristics of SN 2008ax are reminiscent of those of SN 1993J, except for a likely smaller H mass. This may account for the findings that the progenitor of SN 2008ax was a WNL star and not a K supergiant as in the case of SN 1993J, that a prominent early-time peak is missing in the light curve of SN 2008ax, and that Halpha is observed at higher velocities in SN 2008ax than in SN 1993J.Comment: 10 pages, including 8 figures and 4 tables. Accepted for publication in MNRA
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