518 research outputs found
Molecular phylogeny of brachiopods and phoronids based on nuclear-encoded small subunit ribosomal RNA gene sequences
Brachiopod and phoronid phylogeny is inferred from SSU rDNA sequences of 28 articulate and nine inarticulate brachiopods, three phoronids, two ectoprocts and various outgroups, using gene trees reconstructed by weighted parsimony, distance and maximum likelihood methods. Of these sequences, 33 from brachiopods, two from phoronids and one each from an ectoproct and a priapulan are newly determined. The brachiopod sequences belong to 31 different genera and thus survey about 10% of extant genus-level diversity. Sequences determined in different laboratories and those from closely related taxa agree well, but evidence is presented suggesting that one published phoronid sequence (GenBank accession UO12648) is a brachiopod-phoronid chimaera, and this sequence is excluded from the analyses. The chiton, Acanthopleura, is identified as the phenetically proximal outgroup; other selected outgroups were chosen to allow comparison with recent, non-molecular analyses of brachiopod phylogeny. The different outgroups and methods of phylogenetic reconstruction lead to similar results, with differences mainly in the resolution of weakly supported ancient and recent nodes, including the divergence of inarticulate brachiopod sub-phyla, the position of the rhynchonellids in relation to long- and short-looped articulate brachiopod clades and the relationships of some articulate brachiopod genera and species. Attention is drawn to the problem presented by nodes that are strongly supported by non-molecular evidence but receive only low bootstrap resampling support. Overall, the gene trees agree with morphology-based brachiopod taxonomy, but novel relationships are tentatively suggested for thecideidine and megathyrid brachiopods. Articulate brachiopods are found to be monophyletic in all reconstructions, but monophyly of inarticulate brachiopods and the possible inclusion of phoronids in the inarticulate brachiopod clade are less strongly established. Phoronids are clearly excluded from a sister-group relationship with articulate brachiopods, this proposed relationship being due to the rejected, chimaeric sequence (GenBank UO12648). Lineage relative rate tests show no heterogeneity of evolutionary rate among articulate brachiopod sequences, but indicate that inarticulate brachiopod plus phoronid sequences evolve somewhat more slowly. Both brachiopods and phoronids evolve slowly by comparison with other invertebrates. A number of palaeontologically dated times of earliest appearance are used to make upper and lower estimates of the global rate of brachiopod SSU rDNA evolution, and these estimates are used to infer the likely divergence times of other nodes in the gene tree. There is reasonable agreement between most inferred molecular and palaeontological ages. The estimated rates of SSU rDNA sequence evolution suggest that the last common ancestor of brachiopods, chitons and other protostome invertebrates (Lophotrochozoa and Ecdysozoa) lived deep in Precambrian time. Results of this first DNA-based, taxonomically representative analysis of brachiopod phylogeny are in broad agreement with current morphology-based classification and systematics and are largely consistent with the hypothesis that brachiopod shell ontogeny and morphology are a good guide to phylogeny
The measurement of sediment irrigation rates: A comparison of the BR- tracer and 222RN/226RA disequilibrium techniques
We have carried out a series of experiments designed to allow comparison of sediment irrigation rates determined simultaneously using two methods: the measurement of 222Rn/226Ra disequilibrium in pore waters, and the measurement of distributions of a tracer, Br−, which was added to the water overlying sediments at the start of incubation experiments. The experiments were carried out on fine-grained sediments from Buzzards Bay, MA. We made irrigation rate measurements on sediments in their natural state, as well as on sediments that had been treated to alter macrofaunal abundance and diversity. The range of irrigation rates measured was similar for both tracers, and was similar to rates measured at the study site previously by Martin and Sayles (1987). Furthermore, the two tracers gave similar patterns of irrigation rate variability between cores and with depth below the sediment-water interface. On the other hand, comparisons of individual cores showed significant differences in the absolute rates measured using the different tracers; in particular, the 222Rn/226Ra disequilibrium method yielded more rapid irrigation rate estimates at depths exceeding 10 cm below the sediment-water interface. These differences could be due to the inherent limitations on the sensitivity of the methods, to artifacts in measurement procedures, to differences in the permeability of burrow walls to the two tracers (Rn and Br−), or to differences in the time-scales on which the two tracers record irrigation events. Irrigation rates determined by the Br− tracer method were roughly correlated with the abundance of Nephtys incisa in the sediments, but were not related to abundances of the other numerically important deposit feeders, Nucula annulata and Mediomastus ambiseta.
Mapping of health technology assessment in selected countries
Objectives: The aim of this study was to develop and apply an instrument to map the level of health technology assessment (HTA) development at country level in selected countries. We examined middle-income countries (Argentina, Brazil, India, Indonesia, Malaysia, Mexico, and Russia) and countries well-known for their comprehensive HTA programs (Australia, Canada, and United Kingdom).
Methods: A review of relevant key documents regarding the HTA process was performed to develop the instrument which was then reviewed by selected HTAi members and revised. We identified and collected relevant information to map the level of HTA in the selected countries. This was supplemented by information from a structured survey among HTA experts in the selected countries (response rate: 65/385).
Results: Mapping of HTA in a country can be done by focusing on the level of institutionalization and the HTA process (identification, priority setting, assessment, appraisal, reporting, dissemination, and implementation in policy and practice). Although HTA is most advanced in industrialized countries, there is a growing community in middle-income countries that uses HTA. For example, Brazil is rapidly developing effective HTA programs. India and Russia are at the very beginning of introducing HTA. The other middle-income countries show intermediate levels of HTA development compared with the reference countries.
Conclusions: This study presents a set of indicators for documenting the current level and trends in HTA at country level. The findings can be used as a baseline measurement for future monitoring and evaluation. This will allow a variety of stakeholders to assess the development of HTA in their country, help inform strategies, and justify expenditure for HTA
Comparative study of visual performance with tinted soft contact lenses vs. clear soft contact lenses and tinted spectacles under bright outdoor conditions; Phase II
Background: Research has clearly shown the advantages of performance tinted CL wear with regard to various measures of objective and subjective responses under various lighting conditions. The current study expanded upon these results.
Methods: Subjects were 38 non-presbyopic emmetropes or slight ametropes with distance Snellen acuity of 20/20 or better while wearing -0.50 D spherical Acuvue 2 CLs. Measurements of 6m tachistoscopic stereoacuity and variable distance timed and tachistoscopic texture gradient recognition were obtained with subjects wearing clear CLs, tinted spectacles, and SportSight CLs. Lens modality and test sequence were randomized.
Results: Stereoacuity results showed no statistically significant difference in stereolocalization when subjects were wearing clear CLs, SportSight CLs, or tinted spectacles. Texture gradient results using timed and tachistoscopic presentations demonstrated that it was more difficult for subjects to correctly identify the seam orientation at farther distances than nearer distances, and that subjects took more time to try to identify distant target orientation versus near target orientation. In addition, tachistoscopic presentations were not found to be significant with regard to correctness of responses at any distance with any lens modality. Subjective data indicated more physical comfort with either CL modality instead of tinted spectacles. SportSight CLs were also found to be the most visually comfortable modality, followed by tinted spectacles and then clear CLs. Furthermore, a general trend indicated that subjects felt they were able to perform best while wearing the SportSight CLs. This may partially be due to the fact that subjects noted fewer perceptions of stray light with SportSight CLs than with the other modalities. Likewise, subjects reported an equal number of perceived reflections while wearing SportSight CLs and clear CLs but significantly more while wearing tinted spectacles.
Conclusion: Objective findings demonstrated that SportSight CLs provide similar performance with regard to distance depth perception and texture gradient recognition to tinted spectacles. Subjective data indicate that visual comfort of the SportSight CLs was superior to tinted spectacles and clear CLs. Additionally, a trend in subjective data demonstrated that the subjects perceived improved performance on the tests while wearing the SportSight CLs
A study investigating a season\u27s baseball performance while wearing SportSight soft contact lenses
Background: The use of spectacles with colored lenses in sports is well known. Athletes have worn such colored lenses in an attempt to enhance their performance for a number of years with promising results. The integration of wavelength specific filters into contact lenses may provide significant performance enhancement as well as the visual advantages usually afforded by contact lenses relative to spectacles.
Methods: A small group (N=5) of collegiate baseball players were fitted with SportSight soft contact lenses and were asked to wear them during practices and games for half of a season. The players\u27 batting and fielding statistics from the first and second halves of the season were compared to each other and to those of non-participating team members. All of the subjects were existing soft contact lens wearers.
Results: The test group demonstrated dramatic improvements in batting statistics while wearing the SportSight lenses. Their percentage of statistical improvement in each category far surpassed that of non-participating team members.
Conclusion: The results of this pilot study imply that wearing SportSight soft contact lenses yields marked performance enhancement for baseball players. Future studies involving larger subject pools are warranted to thoroughly evaluate the possible statistical significance of these findings
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)
Profiling the molecular destruction rates of temperature and humidity as well as the turbulent kinetic energy dissipation in the convective boundary layer
A simultaneous deployment of Doppler, temperature, and water-vapor lidars is able to provide pro-
files of molecular destruction rates and turbulent kinetic energy (TKE) dissipation in the convective boundary layer
(CBL). Horizontal wind profiles and profiles of vertical wind, temperature, and moisture fluctuations are combined, and
transversal temporal autocovariance functions (ACFs) are determined for deriving the dissipation and molecular de-
struction rates. These are fundamental loss terms in the TKE as well as the potential temperature and mixing ratio variance equations. These ACFs are fitted to their theoretical shapes and coefficients in the inertial subrange. Error bars are estimated by a propagation of noise errors. Sophisticated analyses of the ACFs are performed in order to choose the correct range of lags of the fits for fitting their theoretical shapes in the inertial subrange as well as for minimizing systematic errors due to temporal and spatial averaging and micro- and mesoscale circulations. We demonstrate that we achieve very consistent results of the derived profiles of turbulent variables regardless of whether 1 or 10 s time resolutions are used
Bringing dogs onto campus : inclusions and exclusions of animal bodies in organisations
Since the early years of the 20th century, work organizations have largely been places where animal bodies are absent or invisible. Recently, US and UK universities have facilitated therapy dog visits to improve students' wellbeing. In this article we analyse data on therapy dog visits to a UK university library as a starting point for thinking about other than human animals in organizations and the gendered dimensions of their inclusion and exclusion. Rather than focusing solely on the benefits of these encounters for students, we put the experiences of the dogs and their guardians centre stage, along with those of the library staff and the students. Drawing on observations of visits to a UK university library in 2015–2016, and a total of 16 interviews with library staff, guardians and students, we explore the instrumental rationale for the programme and the efforts to control any potential disruption of normative organizational expectations
DETERMINATION OF TYPES OF INDIVIDUALS IN APHIDS, ROTIFERS AND CLADOCERA 1
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72827/1/j.1469-185X.1929.tb00888.x.pd
Profiling the molecular destruction rates of temperature and humidity as well as the turbulent kinetic energy dissipation in the convective boundary layer
A simultaneous deployment of Doppler, temperature, and water-vapor lidars is able to provide profiles of molecular destruction rates and turbulent kinetic energy (TKE) dissipation in the convective boundary layer (CBL). Horizontal wind profiles and profiles of vertical wind, temperature, and moisture fluctuations are combined, and transversal temporal autocovariance functions (ACFs) are determined for deriving the dissipation and molecular destruction rates. These are fundamental loss terms in the TKE as well as the potential temperature and mixing ratio variance equations. These ACFs are fitted to their theoretical shapes and coefficients in the inertial subrange. Error bars are estimated by a propagation of noise errors. Sophisticated analyses of the ACFs are performed in order to choose the correct range of lags of the fits for fitting their theoretical shapes in the inertial subrange as well as for minimizing systematic errors due to temporal and spatial averaging and micro- and mesoscale circulations. We demonstrate that we achieve very consistent results of the derived profiles of turbulent variables regardless of whether 1 or 10 s time resolutions are used. We also show that the temporal and spatial length scales of the fluctuations in vertical wind, moisture, and potential temperature are similar with a spatial integral scale of ≈160 m at least in the mixed layer (ML). The profiles of the molecular destruction rates show a maximum in the interfacial layer (IL) and reach values of ϵm≃7×10-4 g2 kg−2 s−1 for mixing ratio and ϵθ≃1.6×10-3 K2 s−1 for potential temperature. In contrast, the maximum of the TKE dissipation is reached in the ML and amounts to ≃10-2 m2 s−3. We also demonstrate that the vertical wind ACF coefficient kw∝w′2‾ and the TKE dissipation ϵ∝w′2‾3/2. For the molecular destruction rates, we show that ϵm∝m′2‾w′2‾1/2 and ϵθ∝θ′2‾w′2‾1/2. These equations can be used for parameterizations of ϵ, ϵm, and ϵθ. All noise error bars are derived by error propagation and are small enough to compare the results with previous observations and large-eddy simulations. The results agree well with previous observations but show more detailed structures in the IL. Consequently, the synergy resulting from this new combination of active remote sensors enables the profiling of turbulent variables such as integral scales, variances, TKE dissipation, and the molecular destruction rates as well as deriving relationships between them. The results can be used for the parameterization of turbulent variables, TKE budget analyses, and the verification of large-eddy simulations.</p
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