32,386 research outputs found
Taxonomy of the fouling cheilostome bryozoans, Schizoporella unicornis, (Johnston) and Schizoporella errata (Waters)
Figure 1. (AâD) Images of Wood's Pliocene specimen from the Coralline Crag, Suffolk (NHM B1675) described in Busk (1859). (A) Group of autozooids at growing edge of colony within small bivalve shell. (B) Autozooids exhibiting deep V-shaped sinus. (C) Frontal shield with paired avicularia and deep V-shaped sinus. (D) Detail of primary orifice and sinus. (E, F) Lectotype of Schizoporella unicornis [NHM 1847.16.174 (a)] bleached portion. (E) Group of autozooids at the distal edge of colony with adventitious avicularia, paired, single or absent. (F) Ovicellate autozooids showing radially aligned scalloped grooves. Scale bars: 500 ”m (A); 250 ”m (B); 100 ”m (C, E); 50 ”m (D,F).Published as part of Tompsett, Scott, Porter, Joanne S. & Taylor, Paul D., 2009, Taxonomy of the fouling cheilostome bryozoans Schizoporella unicornis (Johnston) and Schizoporella errata (Waters), pp. 2227-2243 in Journal of Natural History 43 (35-36) on page 2231, DOI: 10.1080/00222930903090140, http://zenodo.org/record/521715
Rapid, Specific Determination of Iodine and Iodide by Combined Solid-Phase Extraction/Diffuse Reflectance Spectroscopy
A new, rapid methodology for trace analysis using solid-phase extraction is described. The two-step methodology is based on the concentration of an analyte onto a membrane disk and on the determination by diffuse reflectance spectroscopy of the amount of analyte extracted on the disk surface. This method, which is adaptable to a wide range of analytes, has been used for monitoring ppm levels of iodine and iodide in spacecraft water. Iodine is used as a biocide in spacecraft water. For these determinations, a water sample is passed through a membrane disk by means of a 10-mL syringe that is attached to a disk holder assembly. The disk, which is a polystyreneâdivinylbenzene composite, is impregnated with poly(vinylpyrrolidone) (PVP), which exhaustively concentrates iodine as a yellow iodineâPVP complex. The amount of concentrated iodine is then determined in only 2 s by using a hand-held diffuse reflectance spectrometer by comparing the result with a calibration curve based on the KubelkaâMunk function. The same general procedure can be used to determine iodide levels after its facile and exhaustive oxidation to iodine by peroxymonosulfate (i.e., Oxone reagent). For samples containing both analytes, a two-step procedure can be used in which the iodide concentration is calculated from the difference in iodine levels before and after treatment of the sample with peroxymonosulfate. With this methodology, iodine and iodide levels in the 0.1â5.0 ppm range can be determined with a total workup time of âŒ60 s with a RSD of âŒ6%
Rapid, Low Level Determination of Silver(I) in Drinking Water by Colorimetricâsolid-phase Extraction
A rapid, highly sensitive two-step procedure for the trace analysis of silver(I) is described. The method is based on: (1) the solid-phase extraction (SPE) of silver(I) from a water sample onto a disk impregnated with a silver-selective colorimetric reagent, and (2) the determination of the amount of complexed analyte extracted by the disk by diffuse reflectance spectroscopy (DRS). This method, called colorimetricâsolid-phase extraction (CâSPE), was recently shown effective in determining low concentrations (0.1â5.0 mg/ml) of iodine and iodide in drinking water. This report extends CâSPE to the trace (âŒ4 ÎŒg/l) level monitoring of silver(I) which is a biocide used on the International Space Station (ISS). The determination relies on the manually driven passage of a water sample through a polystyreneâdivinylbenzene disk that has been impregnated with the colorimetric reagent 5-(p-dimethylaminobenzylidene) rhodanine (DMABR) and with an additive such as a semi-volatile alcohol (1,2-decanediol) or nonionic surfactant (Brij 30). The amount of concentrated silver(I) is then determined in a few seconds by using a hand-held diffuse reflectance spectrometer, with a total sample workup and readout time of âŒ60 s. Importantly, the additive induces the uptake of water by the disk, which creates a local environment conducive to silver(I) complexation at an extremely high concentration factor (âŒ800). There is no detectable reaction between silver(I) and impregnated DMABR in the absence of the additive. This strategy represents an intriguing new dimension for CâSPE in which additives, directly loaded in the disk material, provide a means to manipulate the reactivity of the impregnated reagent
Gravity-assisted trajectories for unmanned space exploration
Gravity assistance to modify heliocentric trajectories of manned space probe
Lighting as a Circadian Rhythm-Entraining and Alertness-Enhancing Stimulus in the Submarine Environment
The human brain can only accommodate a circadian rhythm that closely follows 24 hours. Thus, for a work schedule to meet the brainâs hard-wired requirement, it must employ a 24 hour-based program. However, the 6 hours on, 12 hours off (6/12) submarine watchstanding schedule creates an 18-hour âdayâ that Submariners must follow. Clearly, the 6/12 schedule categorically fails to meet the brainâs operational design, and no schedule other than one tuned to the brainâs 24 hour rhythm can optimize performance. Providing Submariners with a 24 hour-based watchstanding scheduleâcombined with effective circadian entrainment techniques using carefully-timed exposure to lightâwould allow crewmembers to work at the peak of their daily performance cycle and acquire more restorative sleep. In the submarine environment, where access to natural light is absent, electric lighting can play an important role in actively entrainingâand closely maintainingâcircadian regulation. Another area that is likely to have particular importance in the submarine environment is the potential effect of light to help restore or maintain alertness
An expert review of REVERIE and its potential for game-based learning
REVERIE (REal and Virtual Engagement in Realistic Immersive Environments) is a research project with the aim to build a safe, collaborative, online environment which brings together realistic inter-personal communication and interaction. The REVERIE platform integrates cutting-edge technologies and tools, such as social networking services, spatial audio adaptation techniques, tools for creating personalized lookalike avatars, and artificial intelligence (A.I) detection features of the userâs affective state into two distinct use cases. The first shows how REVERIE can be used in educational environments with an emphasis on social networking and learning. The second aims to emulate the look and feel of real physical presence and interaction for entertainment and collaborative purposes. This paper presents an expert evaluation of the first use case by potential users of REVERIE (teachers and students). Finally, the potential of REVERIE for game-based learning is discussed and follow this with an overview of the actionable recommendations that emerged as a result of the expert review
Control in the technical societies: a brief history
By the time control engineering emerged as a coherent body of knowledge and practice (during and just after WW2) professional engineering societies had existed for many decades. Since control engineering is an interdisciplinary branch of the profession, new sections devoted to control were quickly established within the various existing technical societies. In addition, some new bodies devoted specifically or primarily to control were established. This article, a revised version of a paper presented at the IEEE 2009 Conference on the History of Technical Societies, describes how control engineering as a distinct branch of engineering became represented in technical societies in a number of countries
Long-term material compatibility testing system
System includes procedure for hermetically sealing solid materials and fluids in glass ampoule and use of temperature-controlled facility containing sample holder, which permits sample containers to be retrieved safely and conveniently. Solid material and fluid are sealed within chemically-clean glass ampoule according to highly detailed procedure
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Suicide and self-harm in Britain: researching risk and resilience using UK surveys
Aim The main aim of this study was to raise awareness of surveys that could be used to inform self-harm and suicide prevention work. We asked:
What UK survey datasets are available for research?
What aspects of peopleâs lives are associated with self-harm and attempted suicide?
How do statistical findings resonate with peopleâs lived experience? What implications do they see?
Findings Survey analyses revealed that risk factors for self-harm are wide ranging and include:
Mental health
Physical health and health behaviours
Social relationships
Stressful events
Employment and financial circumstances
Identity and demographics
Many different factors are independently associated with self-harm. There is a dose relationship, with more exposure to a factor linked with increased risk. Risks are cumulative that is, exposure to multiple factors is associated with greater risk.
Through facilitated consultation, men with lived experience, bereaved family members, and practitioners identified recommendations for responding to suicidal distress in men. These related to the following three main areas:
1. Recognising need: who is âill enoughâ?
Permission - men said that they often did not know they were entitled to help
Ask - people who outwardly appear to be functioning may not be
Persistence - ask and offer help more than once.
2. Facilitating access: right words, time and place
What is available - support is needed with ongoing stress as well as for crises
Find the words - men wanted examples of how to ask for help
Allow time - employers expect recovery to be swift, some men felt rushed to come off medications or were discharged from services they still needed.
3. Adjusting delivery: equal engagement
Power - some were uncomfortable with service dynamics, preferring peer support
Every service contact counts - negative contacts had particular impact
Safe spaces - may be different for men and women.
Methods
There were three strands of work:
Secondary analysis of nine survey series, spanning more than twenty years
Linkage of 144,000 survey participants to information on whether they were alive in 2013 and whether they had taken their own life
Facilitated consultation, through depth interviews with people with lived experience
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