15,423 research outputs found
Enquiring into writing development across research degrees: a new generative model
This paper reports a UK Higher Education Academy funded study aimed at exploring research studentsâ perceptions of what helps them develop their academic writing. Recent graduates and students from across disciplines were asked questions around four themes: (a) supervisorsâ feedback; (b) training; (c) cohort experiences; and (d) personal strategies for writing development. This paper builds on the interim results discussed at BERA 2012 and presents a new generative model of research studentsâ academic writing development. The model includes the factors influencing this development and captures the dynamic processes that affect higher level thinking. The model may be used as a discussion tool to build a shared student-staff understanding of effective feedback for academic writing across research degree providers globally
At-vessel fishing mortality for six species of sharks caught in the northwest Atlantic and Gulf of Mexico
From 1994-2005 the Commercial Shark Fishery Observer Program (CSFOP) placed fishery observers aboard US bottom longline vessels engaged in directed fishing for sharks in the region from New Jersey to Louisiana, USA. Observers routinely recorded species specific at-vessel mortality as related to enduring the stress oflongline capture. Data for 5 species of sharks (sandbar Carcharhinus plumbeus, blacktip Carcharhinus limbatus, dusky Carcharhinus obscurus, tiger Galeocerdo cuvier, scalloped hammerhead Sphyrna lewini, and great hammerhead Sphyrna mokilrran) were analyzed in this study. Multiple stepwise linear regressions indicate that age group, soak time and bottom water temperature can be used as predictors of at-vessel mortality and that size restrictions, size selective gear, restricting the soak time and time/area closures may be beneficial to fisheries targeting large coastal sharks
Unemployment Dynamics, Duration and Equilibrium: Evidence from Britain
This paper challenges the consensus on the nature of unemployment dynamics in Britain. We show that the argument that changes in unemployment arise mostly from changes in the duration of unemployment (rather than in the chance of becoming unemployed) is flawed. In fact, while shocks to the outflow do have a part to play up to the late 1970s, the huge changes in unemployment over the last two decades have been mostly driven by inflow shocks. Our model also provides a new explanation of aggregate unemployment persistence based on externalities at a market level rather than individual-level persistence.Unemployment dynamics, unemployment duration, unemployment flows, nonlinear dynamics, persistence
The chemistry of ultrasonic degradation of organic compounds
The destruction of toxic organic molecules using advanced oxidation processes (AOPs) is a potent tool for pollution control and environmental protection. Ultrasound is a convenient and effective method of generating hydroxyl radicals which is the key oxidant in AOPs. This review describes the use of ultrasound and associated chemical reactions, with and without additives, as a powerful means of remediating water contaminated with organic pollutants. After a brief introduction to ultrasound and sonochemistry, their application for the oxidation of polycyclic aromatic hydrocarbons, phenol and substituted phenols is considered. Next is the decomposition of chlorinated phenols, and other chlorinated organics, then removal of recalcitrant smaller organic molecules. A discussion follows of recent work that has investigated the effects of initial concentration of substrates; the use of different ultrasonic frequencies; the inclusion of oxidising species, inorganic particles, or salts and their contribution to enhanced degradation. Finally, brief comments are made on the status of ultrasound as an AOP treatment
Advanced Fenton processing of aqueous phenol solutions:a continuous system study including sonication effects
Our previous report based on a batch reactor system for the Advanced Fenton Process (AFP) showed that pH, hydrogen peroxide and the organic substances treated are among the most important factors affecting the oxidation efficiency. As an extended study towards its commercialisation, this paper reports the effects of the main process parameters including those relating to a new AFP flow-through system. In order to systemise and correlate the results, the Taguchi experimental design method was used. Total organic carbon (TOC) removal was utilised as the measure of the oxidation efficiency and it was found that the removal of phenol from aqueous solution at pH 2.0 and 2.5 was very similar but hydrogen peroxide supply significantly affected the TOC removal with the change of flow rate from 14.4 mL/hr to 60 mL/hr. Also, the initial concentration of phenol was a highly significant factor, with higher concentrations resulting in a lower TOC removal rate. The temperature effects in the range of 14 °C to 42 °C were investigated and it was found that there was accelerated oxidation of phenol in the early stages but after 90 minutes there was no significant difference between the results. Sonication with a bath type sonicator resulted in relatively small enhancements of TOC removal but further studies with cup-horn and probe type sonicators showed that TOC removal increased with higher intensity of sonication on additional input of hydrogen peroxide
On the GBM event seen 0.4 sec after GW 150914
In view of the recent report by Connaughton we analyse continuous TTE data of
Fermi-GBM around the time of the gravitational wave event GW 150914. We find
that after proper accounting for low count statistics, the GBM transient event
at 0.4 s after GW 150914 is likely not due to an astrophysical source, but
consistent with a background fluctuation, removing the tension between the
INTEGRAL/ACS non-detection and GBM. Additionally, reanalysis of other short
GRBs shows that without proper statistical modeling the fluence of faint events
is over-predicted, as verified for some joint GBM-ACS detections of short GRBs.
We detail the statistical procedure to correct these biases. As a result, faint
short GRBs, verified by ACS detections, with significances in the broad-band
light curve even smaller than that of the GBM-GW150914 event are recovered as
proper non-zero source, while the GBM-GW150914 event is consistent with zero
fluence.Comment: 13 pages, 12 figures, ApJL (acc.); subm. 2016 March 10, Apr 21 (1st
rev.), May 13 (2nd rev), Jun 1 (3rd rev), and editorial changes by Jun 2 (4th
rev), Jun 8 (5th rev): Our manuscript refers exclusively to
arXiv:1602.03920.v3 since we had no prior access to arXiv:1602.03920.v4/5
(2016 May 31). Note that JG and HFY are not co-authors on
arXiv:1602.03920.v4/
Prepontine non-giant neurons drive flexible escape behavior in zebrafish
Many species execute ballistic escape reactions to avoid imminent danger. Despite fast reaction times, responses are often highly regulated, reflecting a trade-off between costly motor actions and perceived threat level. However, how sensory cues are integrated within premotor escape circuits remains poorly understood. Here, we show that in zebrafish, less precipitous threats elicit a delayed escape, characterized by flexible trajectories, which are driven by a cluster of 38 prepontine neurons that are completely separate from the fast escape pathway. Whereas neurons that initiate rapid escapes receive direct auditory input and drive motor neurons, input and output pathways for delayed escapes are indirect, facilitating integration of cross-modal sensory information. These results show that rapid decision-making in the escape system is enabled by parallel pathways for ballistic responses and flexible delayed actions and defines a neuronal substrate for hierarchical choice in the vertebrate nervous system
Magnetic Field Rotations in the Solar Wind at Kinetic Scales
The solar wind magnetic field contains rotations at a broad range of scales,
which have been extensively studied in the MHD range. Here we present an
extension of this analysis to the range between ion and electron kinetic
scales. The distribution of rotation angles was found to be approximately
log-normal, shifting to smaller angles at smaller scales almost self-similarly,
but with small, statistically significant changes of shape. The fraction of
energy in fluctuations with angles larger than was found to drop
approximately exponentially with , with e-folding angle at
ion scales and at electron scales, showing that large angles
() do not contain a significant amount of energy at kinetic
scales. Implications for kinetic turbulence theory and the dissipation of solar
wind turbulence are discussed
Admission of Liability
There is a great amount of resistance to the admission of liability when the slightest defense is available. Many defendants\u27 attorneys would prefer to take the long chance of hoping for an unexpected verdict rather than admit fault and leave only the issue of damages to the jury. Surprisingly, there have actually been cases in which liability was admitted and the jury returned a verdict of no cause of action. Generally speaking, though, an admission of liability will tend to keep the damage award reasonable, but it will take away the slight possibility of an unexpected defendant\u27s verdict
Lung Cancer Liability of Cigarette Manufacturers
The medical evidence is quite strong as to tobacco causation of lung cancer. However, this leaves several legal questions to be answered before a plaintiff can recover from a cigarette manufacturer. The primary question at hand is: Do cigarette manufacturers impliedly warrant that their product is not dangerous to health; or, if not, do they have a duty to warn the public or the consumers in some direct way of the probable dangers to health in smoking. To phrase it differently, recovery will most likely lie in either implied warranty or in negligence, until statutory provisions are made to help with the problem
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