9,642 research outputs found

    Summer Ephemeroptera, Plecoptera, and Trichoptera (EPT) Species Richness and Community Structure in the Lower Illinois River Basin of Illinois

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    Ephemeroptera, Plecoptera, and Trichoptera (EPT) species richness is useful for monitoring stream health, but no published studies in Illinois quantitatively document EPT richness or assemblage structure. The objectives of this study were to characterize adult EPT richness and structure and relate these to relative water at eight stream sites (160-69,300 km3 area) in the lower Illinois River Adults were ultra-violet light trapped in June, July, and August 1997. Nutrient enrichment by nitrate and nitrite nitrogen was strongly evident, in smaller drainages, while critical loss of stable habitat was observed in water bodies. Seventy EPT species were identified from 17,889 specimens. Trichoptera were by far the most speciose (41 species), followed by Ephemeroptera (26), and Plecoptera (3). Caddisflies also dominated species richness across sites, contributing 18.0 of the average 28.9 total EPT species collected. Site EPT richness varied significantly (F =5.51, p 0.003, df 7), with smaller drainages supporting greater richness, generally. Differences were also evident for months (F = 21.7, p =0.0001, df =2), with June being lower (11.8 average) than either July (20.6) or August (18.1) values. Hilsenhoff biotic index (HBI) scores did not vary significantly across sites (F 0.7, p =0.7, df =7), but were different across months (F =5.4, p 0.02, df 2). June (4.23) and July (4.53) means were not different, but both were lower (of better quality) than August (5.33) scores. The relationship of EPT to HBI scores was not investigated statisti- cally due to problems of sample size and interdependance of monthly sam­ ples, but graphical analysis no consistent relationship. This sug- gested a decoupling of the the EPT and implied that the gain in taxonomic resolution achieved by adults outstripped the resolution of the HBI. Use of the HBI to characterize adult aquatic insect communities is discouraged. New state records and extensions for Ephemeroptera and Trichoptera are presented and loss of sensitive Plecoptera in the drainage is discussed

    The Rule of Law in Athenian Democracy. Reflections on the Judicial Oath

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    This essay examines the terms of the Judicial Oath sworn by the judges in the Athenian courts during the classical period. There is general agreement that the oath contained four basic clauses: (1) to vote in accordance to the laws and decrees of the Athenian people, (2) to vote about matters pertaining to the charge, (3) to listen to both the accuser(s) and defendant(s) equally, and (4) to vote or judge (dikasein) with one’s most fair judgment (dikaiotatê gnômê). Some scholars believe that the fourth clause gave judges the right to vote according to their conscience and to ignore the law if they found it unjust. The first part of the essay shows that this clause gave judges the right to make decisions solely on the basis of their most just judgment only where the laws gave no clear guidance. It was a default clause invoked only twice in the extant orations; it was never used as justification to ignore the written laws. The second part addresses the view that the courts took political factors into account during trials. Although some trials involved leading politicians, the courts were bound by their oath to decide whether the defendant was guilty of the charge brought by the accuser. The only part of a trial where a defendant might mention his political achievements or his public largesse was at during the assessment of the penalty (timêsis) in a trial on a public charge (graphê)

    The 2060 Chiron: CCD photometry

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    R-band CCD photometry of 2060 was carried out on nine nights in Nov. and Dec. 1986. The rotation period is 5.9181 + or - 0.0003 hr and the peak to peak lightcurve amplitude is 0.088 + or - 0.0003 mag. Photometric parameters are H sub R = 6.24 + or - 0.02 mag and G sub R = + or - 0.15, though formal errors may not be realistic. The lightcurve has two pairs of extrema, but its asymmetry, as evidenced by the presence of significant odd Fourier harmonics, suggests macroscopic surface irregularities and/or the presence of some large scale albedo variegation. The observational rms residual is + or - 0.015 mag. On time scales from minutes to days there is no evidence for nonperiodic (cometary) brightness changes at the level of a few millimagnitudes

    Survivor-complier effects in the presence of selection on treatment, with application to a study of prompt ICU admission

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    Pre-treatment selection or censoring (`selection on treatment') can occur when two treatment levels are compared ignoring the third option of neither treatment, in `censoring by death' settings where treatment is only defined for those who survive long enough to receive it, or in general in studies where the treatment is only defined for a subset of the population. Unfortunately, the standard instrumental variable (IV) estimand is not defined in the presence of such selection, so we consider estimating a new survivor-complier causal effect. Although this effect is generally not identified under standard IV assumptions, it is possible to construct sharp bounds. We derive these bounds and give a corresponding data-driven sensitivity analysis, along with nonparametric yet efficient estimation methods. Importantly, our approach allows for high-dimensional confounding adjustment, and valid inference even after employing machine learning. Incorporating covariates can tighten bounds dramatically, especially when they are strong predictors of the selection process. We apply the methods in a UK cohort study of critical care patients to examine the mortality effects of prompt admission to the intensive care unit, using ICU bed availability as an instrument

    The Plaint in Athenian Law and Legal Procedure

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    This essay examines the contents of the plaint (engklema) and its role in Athenian law and legal procedure. The plaint contained the full names of the accuser and the defendant with patronymic and demotic and the name of the action the accuser was bringing against the defendant and the names of those who witnessed the summons. The plaint also contained a brief summary of the accuser’s main charges all expressed in the language of the relevant statute. The plaint therefore determined the main issues about which the judges would decide and defined what was relevant and irrelevant (exo tou pragmatos). It ensured that the judges would concentrate on the question, did the defendant violate the law? and that they would pay no attention to irrelevant issues like public service. After the trial, the plaint was kept on file in the office of the relevant magistrate and could be produced as evidence in subsequent litigation. In this way it helped to uphold the important principle of res iudicata

    Carbon-13 nuclear magnetic resonance spectra and mechanism of bridge–terminal carbonyl exchange in di-µ-carbonyl-bis[carbonyl(η-cyclopentadienyl)iron](Fe–Fe)[{(η-C5H5)Fe(CO)2}2]; cd-di-µ-carbonyl-f-carbonyl-ae-di(η-cyclopentadienyl)-b-(triethyl -phosphite)di-iron(Fe–Fe)[(η-C5H5)2Fe2(CO)3P(OEt)3], and some related complexes

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    A mechanism involving carbonyl-bridge breaking, rotation about the Fe–Fe bond, and bridge reformation is shown to account qualitatively for changes in the carbonyl region of the 13C n.m.r spectrum of the complex [(cp)(OC)[graphic omitted]e(cp){P(OEt)3}] and quantitatively for [(cp)(OC)[graphic omitted]e(CO)(cp)](cp =η-cyclopentadienyl).The activation energy for this process, 49.0 ± 4 kJ mol^–1(11.7 ± 1 kcal mol^–1), is close to that reported for cis–trans-isomerization of the cp groups, in accord with this mechanism. Variable-temperature 13C n.m.r. spectra of the complexes [(cp)(OC)[graphic omitted]u(CO)(cp)] and [(cp)(OC)[graphic omitted]i(cp)] are also reported

    LSST: Comprehensive NEO Detection, Characterization, and Orbits

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    (Abridged) The Large Synoptic Survey Telescope (LSST) is currently by far the most ambitious proposed ground-based optical survey. Solar System mapping is one of the four key scientific design drivers, with emphasis on efficient Near-Earth Object (NEO) and Potentially Hazardous Asteroid (PHA) detection, orbit determination, and characterization. In a continuous observing campaign of pairs of 15 second exposures of its 3,200 megapixel camera, LSST will cover the entire available sky every three nights in two photometric bands to a depth of V=25 per visit (two exposures), with exquisitely accurate astrometry and photometry. Over the proposed survey lifetime of 10 years, each sky location would be visited about 1000 times. The baseline design satisfies strong constraints on the cadence of observations mandated by PHAs such as closely spaced pairs of observations to link different detections and short exposures to avoid trailing losses. Equally important, due to frequent repeat visits LSST will effectively provide its own follow-up to derive orbits for detected moving objects. Detailed modeling of LSST operations, incorporating real historical weather and seeing data from LSST site at Cerro Pachon, shows that LSST using its baseline design cadence could find 90% of the PHAs with diameters larger than 250 m, and 75% of those greater than 140 m within ten years. However, by optimizing sky coverage, the ongoing simulations suggest that the LSST system, with its first light in 2013, can reach the Congressional mandate of cataloging 90% of PHAs larger than 140m by 2020.Comment: 10 pages, color figures, presented at IAU Symposium 23

    Establishment of Charter Schools in the Commonwealth of Virginia

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    Virginia is facing significant challenges related to public education such as decreased funding for public education, decreased teacher salaries, and overcrowded classrooms. Senate Joint Resolution 6 was a bill proposed in 2016 that sought to grant the Board of Education authority, subject to criteria and conditions prescribed by the General Assembly, to establish charter schools within the school divisions of the Commonwealth. There are racial implications related to the creation and authorization of charter schools and this report details those impacts and creates a set of recommendations to eliminate racial implementations when determining who authorizes charter schools in the Commonwealth of Virginia
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