Mitigating agrichemicals from an artificial runoff event using a managed riverine wetland

We examined the mitigation efficiency of a managed riverine wetland amended with a mixture of suspended sediment, two nutrients (nitrogen and phosphorus), and three pesticides (atrazine, metolachlor, and permethrin) during a simulated agricultural runoff event. Hydrologic management of the 500 m-long, 25 mwide riverine wetland was done by adding weirs at both ends. The agrichemical mixture was amended to the wetland at the upstream weir simulating a four-hour, ~1 cm rainfall event from a 16 ha agricultural field. Water samples (1 L) were collected every 30 min within the first 4 h, then every 4 h until 48 h, and again on days 5, 7, 14, 21, and 28 post-amendment at distances of 0 m, 10 m, 40 m, 300 m and 500 m from the amendment point within the wetland for suspended solids, nutrient, and pesticide analyses. Peak sediment, nutrient, and pesticide concentrations occurred within 3 h of amendment at 0 m, 10 m, 40 m, and 300 m downstream and showed rapid attenuation of agrichemicals from the water column with 79–98%, 42–98%, and 63–98% decrease in concentrations of sediments, nutrients, and pesticides, respectively, within 48 h. By day 28, all amendments were near or below pre-amendment concentrations. Water samples at 500 m showed no changes in sediment or nutrient concentrations; pesticide concentrations peaked within 48 h but at ≤11% of upstream peak concentrations and had dissipated by day 28. Managed riverine wetlands≥1 ha and with hydraulic residence times of days to weeks can efficiently trap agricultural runoff during moderate (1 cm) late-spring and early-summer rainfall events, mitigating impacts to receiving rivers

Recent Cases

Constitutional Law-First Amendment-School Authorities May Prohibit High School Student\u27s Distribution of Sex Questionnaire to Prevent Possible Psychological Harm to Other Students Robert Edward Banta Plaintiff, editor of a high school publication,\u27 brought suit in federal court seeking an order compelling defendant school officials to allow the student publication to distribute a sex questionnaire,to students in the high school and to publish the results. Plaintiff claimed that defendants had not shown that the planned distribution would disrupt school activities and that, therefore, defendants\u27prohibition of the questionnaire violated 42 U.S.C. § 19831 and the first and fourteenth amendments. Pointing to potential psychological harm to students, defendants argued that the state\u27s interest in protecting the students\u27 emotional well-being outweighed plaintiffs interest in distributing the questionnaire. The trial court held that defendants could prohibit distribution of the questionnaire to ninth-and tenth-grade students but not to eleventh- and twelfth-grade students. On appeal to the United States Court of Appeals for the Second Circuit, held, reversed in part\u27 and remanded with instructions to dismiss the complaint. If school officials reasonably believe that distribution on school grounds of a high school student\u27s questionnaire soliciting information about the sexual habits of his fellow students might cause psychological harm to other students, then prohibition of the questionnaire does not violate the right to freedom of expression of the student seeking to distribute the questionnaire. Trachtman v. Anker, 563 F.2d 512 (2d Cir. 1977). Corporations--Freeze-Out Mergers--The Delaware Supreme Court Requires Majority Shareholder Proof of a Valid Business Purpose As a Component of Entire Fairness in Freeze-Out Merger Challenges Oby T. Brewer, III Recent declines in stock market averages\u27 accompanied by costly disclosure requirements imposed under the federal securities laws have prompted many companies to reconsider their positions as publicly held corporations. In response to the resulting minimal benefits of public ownership, many controlling shareholders now seek to increase their control and participation in a corporation\u27s future profits by going private.\u27 One means of going private is the freeze-out merger, by which a parent company forces the liquidation of minority interests in a publicly held subsidiary through a merger of the subsidiary with the parent. By complying with applicable state merger statutes, the parent may eliminate the minority\u27s shares by tendering a cash-out price, which the minority either must accept or have appraised judicially. The merger statutes thus represent a legislative compromise between total majority control and the single vote veto available to the minority at common law. Criminal Procedure--Prosecutorial Immunity-Federal Prosecutor Is Not Absolutely Immune From Suit for Alleged Perjury Cornelia Anne Clark Plaintiffs\u27 brought a civil action in tort charging that defendant federal prosecutor\u27s alleged perjury at a hearing incident to a grand jury investigation of plaintiffs\u27 activities\u27 violated their constitutional rights. On motion to dismiss, defendant contended that he enjoyed absolute quasi-judicial immunity because he had been acting at the hearing in his official capacity as a special federal prosecutor. The district court\u27 denied the motion, holding that the doctrine of quasi-judicial immunity does not apply when the prosecutor is alleged to have committed perjury. On interlocutory appeal to the United States Court of Appeals for the District of Columbia Circuit, held, affirmed. Because a federal prosecutor\u27s perjury during a court hearing incident and prior to a grand jury investigation falls within his investigative duty rather than his advocatory duty,the prosecutor is entitled only to a qualified immunity.\u27 Briggs v.Goodwin, No. 75-1642 (D.C. Cir. Sept. 21, 1977). Securities Law--Rule 10b-5-Defense of In Pari Delicto Bars Private Damage Action Brought Against Tipper by Tippee Who Fails to Disclose Before Trading Terry Currie Tippees\u27 brought a private action for damages under section 10(b) of the Securities Exchange Act of 1934 and rule 10b-53 charging that defendant tippers disseminated false and misleading material inside information in advising plaintiffs of an imminent merger between two corporations that would result in appreciated stock values.\u27 In reliance on this information, plaintiffs purchased stock in one of the corporations and subsequently incurred substantial losses on the stock when the proposed merger did not occur. Defendants moved for summary judgment, claiming that the doctrine of in pari delicto barred plaintiffs\u27 recovery because plaintiffs also had violated rule 10b-5 by failing to make full disclosure of the inside information before trading on the open market.\u27 The district court granted the tippers\u27 motion for summary judgment. On appeal to the United States Court of Appeals for the Third Circuit, held, affirmed. When a tippee violates rule 10b-5 by failing to make full disclosure to the investing public of material inside information prior to trading on the open market, the defense of in pari delicto bars a rule 10b-5 private damage action by the tippee against the tipper. Torts--Negligence--Child Has Cause of Action for Preconception Medical Malpractice Douglas William Ey, Jr. Plaintiff, claiming that she suffered permanent physical injuries\u27 as a result of defendants\u27 conduct prior to her conception,sought to recover damages in a negligence action.2 In 1965 plaintiffs mother,who had Rh negative blood, was given two transfusions of incompatible Rh positive blood in defendant hospital where defendant physician was director of laboratories.\u27 Plaintiff\u27s mother did not discover that these transfusions had sensitized her blood until shortly before plaintiffs birth in 1973. Defendants moved to dis-miss for failure to state a cause of action, arguing that because plaintiff had not been conceived at the time of the alleged negligent conduct, defendants owed no duty of care to plaintiff. The trial court granted defendants\u27 motion, but the Illinois Appellate Court reversed and remanded the case for further proceedings. On appeal to the Supreme Court of Illinois, held, affirmed. A child injured by the negligent acts of a physician and a hospital committed against his mother prior to his conception has a cause of action based on negligence. Renslow v. Mennonite Hospital, 367 N.E.2d 1250 (Ill.1977)

Innovative interstellar explorer

An interstellar "precursor" mission has been under discussion in the scientific community for at least 30 years. Fundamental scientific questions about the interaction of the Sun with the interstellar medium can only be answered with in situ measurements that such a mission can provide. The Innovative Interstellar Explorer (IIE) and its use of Radioisotope Electric Propulsion (REP) is being studied under a NASA "Vision Mission" grant. Speed is provided by a combination of a high-energy launch, using current launch vehicle technology, a Jupiter gravity assist, and long-term, low-thrust, continuous acceleration provided by an ion thruster running off electricity provided by advanced radioisotope electric generators. A payload of ten instruments with an aggregate mass of ~35 kg and requiring ~30 W has been carefully chosen to address the compelling science questions. The nominal 20-day launch window opens on 22 October 2014 followed by a Jupiter gravity assist on 5 February 2016. The REP system accelerates the spacecraft to a "burnout" speed of 7.8 AU per year at 104 AU on 13 October 2032 (Voyager 1's current speed is ~3.6 AU/yr). The spacecraft will return at least 500 bits per second from at least 200 AU ~30 years after launch. Additional (backup) launch opportunities occur every 13 months to early 2018. In addition to addressing basic heliospheric science, the mission will ensure continued information on the far-heliospheric galactic cosmic ray population after the Voyagers have fallen silent and as the era of human Mars exploration begins

GOES-R Geostationary Lightning Mapper Performance Specifications and Algorithms

The Geostationary Lightning Mapper (GLM) is a single channel, near-IR imager/optical transient event detector, used to detect, locate and measure total lightning activity over the full-disk. The next generation NOAA Geostationary Operational Environmental Satellite (GOES-R) series will carry a GLM that will provide continuous day and night observations of lightning. The mission objectives for the GLM are to: (1) Provide continuous, full-disk lightning measurements for storm warning and nowcasting, (2) Provide early warning of tornadic activity, and (2) Accumulate a long-term database to track decadal changes of lightning. The GLM owes its heritage to the NASA Lightning Imaging Sensor (1997- present) and the Optical Transient Detector (1995-2000), which were developed for the Earth Observing System and have produced a combined 13 year data record of global lightning activity. GOES-R Risk Reduction Team and Algorithm Working Group Lightning Applications Team have begun to develop the Level 2 algorithms and applications. The science data will consist of lightning "events", "groups", and "flashes". The algorithm is being designed to be an efficient user of the computational resources. This may include parallelization of the code and the concept of sub-dividing the GLM FOV into regions to be processed in parallel. Proxy total lightning data from the NASA Lightning Imaging Sensor on the Tropical Rainfall Measuring Mission (TRMM) satellite and regional test beds (e.g., Lightning Mapping Arrays in North Alabama, Oklahoma, Central Florida, and the Washington DC Metropolitan area) are being used to develop the prelaunch algorithms and applications, and also improve our knowledge of thunderstorm initiation and evolution

Spectral Typing of Late Type Stellar Companions to Young Stars from Low Dispersion Near-Infrared Integral Field Unit Data

We used the Project 1640 near-infrared coronagraph and integral field spectrograph to observe 19 young solar type stars. Five of these stars are known binary stars and we detected the late-type secondaries and were able to measure their JH spectra with a resolution of R\sim30. The reduced, extracted, and calibrated spectra were compared to template spectra from the IRTF spectral library. With this comparison we test the accuracy and consistency of spectral type determination with the low-resolution near-infrared spectra from P1640. Additionally, we determine effective temperature and surface gravity of the companions by fitting synthetic spectra calculated with the PHOENIX model atmosphere code. We also present several new epochs of astrometry of each of the systems. Together these data increase our knowledge and understanding of the stellar make up of these systems. In addition to the astronomical results, the analysis presented helps validate the Project 1640 data reduction and spectral extraction processes and the utility of low-resolution, near-infrared spectra for characterizing late-type companions in multiple systems.Comment: Accepted to Astronomical Journal, 25 pages, 8 figure

Loose Groups of Galaxies in the Las Campanas Redshift Survey

A ``friends-of-friends'' percolation algorithm has been used to extract a catalogue of dn/n = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups and includes 35% of the LCRS galaxy sample. A clean sample of 394 groups has been derived by culling groups from the full sample which either are too close to a slice edge, have a crossing time greater than a Hubble time, have a corrected velocity dispersion of zero, or contain a 55-arcsec ``orphan'' (a galaxy with a mock redshift which was excluded from the original LCRS redshift catalogue due to its proximity to another galaxy -- i.e., within 55 arcsec). Median properties derived from the clean sample include: line-of-sight velocity dispersion sigma_los = 164km/s, crossing time t_cr = 0.10/H_0, harmonic radius R_h = 0.58/h Mpc, pairwise separation R_p = 0.64/h Mpc, virial mass M_vir = (1.90x10^13)/h M_sun, total group R-band luminosity L_tot = (1.30x10^11)/h^2 L_sun, and R-band mass-to-light ratio M/L = 171h M_sun/L_sun; the median number of observed members in a group is 3.Comment: 32 pages of text, 27 figures, 7 tables. Figures 1, 4, 6, 7, and 8 are in gif format. Tables 1 and 3 are in plain ASCII format (in paper source) and are also available at http://www-sdss.fnal.gov:8000/~dtucker/LCLG . Accepted for publication in the September 2000 issue of ApJ

Electric Field Conjugation with the Project 1640 coronagraph

The Project 1640 instrument on the 200-inch Hale telescope at Palomar Observatory is a coronagraphic instrument with an integral field spectrograph at the back end, designed to find young, self-luminous planets around nearby stars. To reach the necessary contrast for this, the PALM-3000 adaptive optics system corrects for fast atmospheric speckles, while CAL, a phase-shifting interferometer in a Mach-Zehnder configuration, measures the quasistatic components of the complex electric field in the pupil plane following the coronagraphic stop. Two additional sensors measure and control low-order modes. These field measurements may then be combined with a system model and data taken separately using a white-light source internal to the AO system to correct for both phase and amplitude aberrations. Here, we discuss and demonstrate the procedure to maintain a half-plane dark hole in the image plane while the spectrograph is taking data, including initial on-sky performance.Comment: 9 pages, 7 figures, in Proceedings of SPIE, 8864-19 (2013

An Improved Photometric Calibration of the Sloan Digital Sky Survey Imaging Data

We present an algorithm to photometrically calibrate wide field optical imaging surveys, that simultaneously solves for the calibration parameters and relative stellar fluxes using overlapping observations. The algorithm decouples the problem of "relative" calibrations, from that of "absolute" calibrations; the absolute calibration is reduced to determining a few numbers for the entire survey. We pay special attention to the spatial structure of the calibration errors, allowing one to isolate particular error modes in downstream analyses. Applying this to the Sloan Digital Sky Survey imaging data, we achieve ~1% relative calibration errors across 8500 sq.deg. in griz; the errors are ~2% for the u band. These errors are dominated by unmodelled atmospheric variations at Apache Point Observatory. These calibrations, dubbed "ubercalibration", are now public with SDSS Data Release 6, and will be a part of subsequent SDSS data releases.Comment: 16 pages, 17 figures, matches version accepted in ApJ. These calibrations are available at http://www.sdss.org/dr