3,335 research outputs found
A geochemical drainage survey of the Fleet granitic complex and its environs
A regional geochemical drainage reconnaissance programme was undertaken over 900 km2 of south-west Scotland
centred on the Fleet granitic complex. Rocks of Ordovician and Silurian age outcrop over the area, into which have been
intruded the Fleet and Loch Doon plutons.
Multi-element analysis of stream sediments and heavy mineral concentrates shows a number of patterns of trace element
distribution related to different lithologies and to mineralisation. Broad scale patterns exhibited by some elements denote
compositional variations within the Lower Palaeozoic sediments and within the Fleet and Loch Doon plutons.
On thebasis of the drainage data the sedimentary rocks have been divided into eight distinct geochemical units each
characterised by different element distribution patterns. The Fleet and Loch Doon plutons have been sub-divided on the
same basis.
Follow-up investigations of drainage anomalies led to the discovery of both structure-controlled and disseminated base
metal mineralisation in the Penkiln drainage basin within the salthernaureole of the Loch Doon granite. The distribution
of Cu, F’b and Zn to the south and south-west of the Fleet granite suggests a zonation of vein minerahsation, with Cu
prominent adjacent to the granite contact and F’b and Zn having a wider dispersion away from the granite. Other
anomalies delineate a mineralised lineament that follows the regional strike of the Lower Palaeozoic sediments, southeast
of the Fleet granite
A reconnaissance geochemical drainage survey of the Criffel-Dalbeattie granodiorite complex and its environs
Regional geochemical reconnaissance by stream sediments and panned
concentrates was undertaken over an area of 850 km
2
of south-west Scotland.
Rocks of Ordovician to Permian age are exposed within the area but the major
part is occupied by the Criffel-Dalbeattie granodiorite complex.
Multi-element analysis of the samples collected demonstrates
patterns of trace element distribution related to the geology and
Broad-scale patterns in the distribution of some elements reflect compositional
anumber of
mineralisation.
variations in both the Lower Palaeozoic turbidite sequence and the Criffel-
Dalbeattie granodiorite complex, both of which may be sub-divided into specific
units on the basis of the geochemical data.
The follow-up of copper anomalies in drainage samples from the Black
Stockarton Moor area led to the discovery of porphyry-style copper mineralisation
within an arcuate belt at least 5 km by 1 km within the Black Stockarton Moor
subvolcanic complex and of related disseminated copper mineralisation at Screel
Burn. The area to the west of the Criffel-Dalbeattie plutonic complex is also
characterised by relatively high boron levels in stream sediments reflecting
the widespread occurrence of tourmaline both in association with and peripheral
to the copper mineralisation. Vein mineralisation, usually containing baryte
in addition to base.metals, is also identifiable from the drainage survey at
the eastern margin of the Criffel-Dalbeattie granodiorite; in association with
the Lower Carboniferous rocks along the Solway coast; and within the Lower
Palaeozoic turbidites in the west of the area
#cutting: non-suicidal self-injury (NSSI) on Instagram
Social media presents an important means for social interaction, especially among adolescents, with Instagram being the most popular platform in this age-group. Pictures and communication about non-suicidal self-injury (NSSI) can frequently be found on the internet. During 4 weeks in April 2016, n = 2826 (from n = 1154 accounts) pictures which directly depicted wounds on Instagram were investigated. Those pictures, associated comments, and user accounts were independently rated for content. Associations between characteristics of pictures and comments as well as weekly and daily trends of posting behavior were analyzed. Most commonly, pictures depicted wounds caused by cutting on arms or legs and were rated as mild or moderate injuries. Pictures with increasing wound grades and those depicting multiple methods of NSSI generated elevated amounts of comments. While most comments were neutral or empathic with some offering help, few comments were hostile. Pictures were mainly posted in the evening hours, with a small peak in the early morning. While there was a slight peak of pictures being posted on Sundays, postings were rather evenly spread across the week. Pictures of NSSI are frequently posted on Instagram. Social reinforcement might play a role in the posting of more severe NSSI pictures. Social media platforms need to take appropriate measures for preventing online social contagion
Novel pharmacological actions of Trequinsin Hydrochloride improve human sperm cell motility and function
Background and purposeAsthenozoospermia is a leading cause of male infertility, but the development of pharmaceuticals to improve sperm motility has been hindered by the lack of effective screening platforms and knowledge of suitable molecular targets. We have demonstrated that a high throughput screening (HTS) strategy in conjunction with established in vitro tests can identify and characterise the action of compounds that improve sperm motility. The study aimed to apply HTS to identify new compounds from a novel small molecule library that increase intracellular calcium, [Ca2+]I, promote human sperm cell motility and systemically determine the mechanism of action. Experimental approach A validated HTS fluorometric [Ca2+]i assay was used to screen an in-house library of compounds. Trequinsin hydrochloride (a phosphodiesterase 3 inhibitor) was selected for detailed molecular (plate reader assays, electrophysiology and cyclic nucleotide measurement) and functional (motility and acrosome reaction) testing in sperm from healthy volunteer donors and, where possible, patients.  Key resultsThe fluorometric analysis identified Trequinsin as an efficacious agonist of [Ca2+]i, although less potent than progesterone (P4). Functionally, Trequinsin significantly increased cell hyperactivation and penetration into viscous medium in all donor sperm samples and cell hyperactivation in 22/25 (88%) patient sperm samples. The Trequinsin-induced [Ca2+]i response was cross-desensitised consistently by prostaglandin E1 but not with P4. Whole-cell patch clamp electrophysiology confirmed that Trequinsin activates CatSper and partially inhibits potassium channel activity. Trequinsin also increases intracellular cGMP.  Conclusion and Implications Trequinsin exhibits a novel pharmacological profile in human sperm and may be a suitable lead compound for the development of new pharmaceuticals to improve patient sperm function and fertilisation potential
Entropy of Lovelock Black Holes
A general formula for the entropy of stationary black holes in Lovelock
gravity theories is obtained by integrating the first law of black hole
mechanics, which is derived by Hamiltonian methods. The entropy is not simply
one quarter of the surface area of the horizon, but also includes a sum of
intrinsic curvature invariants integrated over a cross section of the horizon.Comment: 15 pages, plain Latex, NSF-ITP-93-4
Kuiper Binary Object Formation
It has been observed that binary Kuiper Belt Objects (KBOs) exist contrary to
theoretical expectations. Their creation presents problems to most current
models. However, the inclusion of a third body (for example, one of the outer
planets) may provide the conditions necessary for the formation of these
objects. The presence of a third massive body not only helps to clear the
primordial Kuiper Belt but can also result in long lived binary Kuiper belt
objects. The gravitational interaction between the KBOs and the third body
causes one of four effects; scattering into the Oort cloud, collisions with the
growing protoplanets, formation of binary pairs, or creation of a single Kuiper
belt object. Additionally, the initial location of the progenitors of the
Kuiper belt objects also has a significant effect on binary formation
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A 3-d modular gripper design tool
Modular fixturing kits are precisely machined sets of components used for flexible, short-turnaround construction of fixtures for a variety of manufacturing purposes. A modular vise is a parallel-jaw vise, where each jaw is a modular fixture plate with a regular grid of precisely positioned holes. A modular vise can be used to locate and hold parts for machining, assembly, and inspection tasks. To fixture a part, one places pins in some of the holes so that when the vise is closed, the part is reliably located and completely constrained. The modular vise concept can be adapted easily to the design of modular parallel-jaw grippers for robots. By attaching a grid plate to each jaw of a parallel-jaw gripper, the authors gain the ability to easily construct high-quality grasps for a wide variety of parts from a standard set of hardware. Wallack and Canny developed a previous algorithm for planning planar grasp configurations for the modular vise. In this paper, the authors expand this work to produce a 3-d fixture/gripper design tool. They describe several analyses added to the planar algorithm to improve its utility, including a three-dimensional grasp quality metric based on geometric and force information, three-dimensional geometric loading analysis, and inter-gripper interference analysis to determine the compatibility of multiple grasps for handing the part from one gripper to another. Finally, the authors describe two applications which combine the utility of modular vise-style grasping with inter-gripper interference: The first is the design of a flexible part-handling subsystem for a part cleaning workcell under development at Sandia National Laboratories; the second is the automatic design of grippers that support the assembly of multiple products on a single assembly line
Rapid Scoping Study on Leicester Drama School
Leicester Castle Business School
Creative and Cultural Industries Research GroupScoping Study and Business Development for a new drama school at Curve Theatre
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Experience with atmospheric fluidized bed gasification of switchgrass
Switchgrass was gasified in a bubbling fluidized bed reactor rated at 800 kW (2.75 MMBtu/hr) thermal input and operating at atmospheric pressure. A combustible gas with higher heating value varying between 4.2--5.9 MJ/Nm{sup 3} (114--160 Btu/scf) was produced. Carbon conversion was approximately 85%. Difficulties in feeding high moisture switchgrass inhibited smooth reactor operation. Several feed systems for switchgrass were tried with varying degrees of success. The results of gasification trials using switchgrass as fuel are described
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