2,021 research outputs found
The proton shift across the mitochondrial membrane associated with potassium uptake induced by valinomycin
The Large Scale X-ray Emission from M87
We describe asymmetrical features in a long exposure X-ray map of M87 made
with the ROSAT High Resolution Imager (HRI). A bright triangular region is
marked by a linear `spur' along one edge. The structure of this spur suggests
an interpretation of a tangential view of a shock front 18 kpc long. None of
the brighter features are spatially coincident with radio or optical structures
so we concur with earlier investigators that most of the emission arises from
thermal processes.Comment: 6 pages latex, including 3 postscript figures. Uses psfig and
LAMUPHYS (Springer) macro. To be published in 'The M87 Ringberg Workshop',
September 1997, Springer Lecture Notes in Physics Series, Roeser and
Meisenheimer, ed
Potential for rainfed woody biomass production for energy conversion in drought and salinity affected areas of northern India
577-582This paper presents production of woody biomass using waste or saline water for irrigation and rain fed biomass production on land with low food crop potential. Woody biomass can be harvested sustainably from indigenous or naturalised vegetation,existing stands can be improved or tree plantations can be established, matching appropriate species to prevailing conditions.Rain fed productivity of woody species in dry areas is limited by soil salinity and water availability and assumptions on biomass productivity and land areas required for energy conversion should be based on yield estimates realistic for local soil and climate,which can be very low. Development of woody biomass production in rural communities needs to be cost effective, have good institutional support and governance, and comprise appropriate technologies and approaches. Woody biomass production potentially raises the issue of competition over land resources with other users and uses of wasteland. Some woody biomasss pecies may also have adverse impacts on biodiversity
Application of a novel CCD technology to medical imaging
This thesis describes an evaluation of a novel low light level charge couple device
(L3CCD) technology.
Two L3CCDs have been fully evaluated in terms of their signal and noise properties.
The primary aim of this work is to identify the device characteristics that affect the
overall performance. Conclusions have been made to this end and a prediction of the
optimal performance in terms of the device sensitivity is made. Comparisons with other
detectors suitable for use in medical imaging have shown that the L3CCD surpasses
other detectors in specific performance characteristics and is comparable in others. The
competitive performance of the L3CCD confirms that it may afford benefits in those
areas in which the L3CCD has superior performance compared to other detectors.
Two diagnostic imaging techniques which were identified as applications of L3CCD
technology have been investigated.
Linear systems analysis has been used to predict the performance of two L3CCD based
imaging systems for use in fluoroscopic imaging. Comparison of the predicted
performance of the two system with systems in clinical use show that an L3CCD
coupled to an x-ray phosphor via a tapered fibre optic is a competitive alternative to
present fluoroscopic imaging systems. Experimental validation of the model has
confirmed this conclusion.
An L3 detector has been designed, built and evaluated for diffraction enhanced breast
imaging. To demonstrate the use of the L3 detector for diffraction enhanced breast
imaging it has been used to acquire diffraction images of human breast tissue with
cancerous inclusions. Measurements of scatter contrast confirm improvements in
scatter contrast compared to transmission contrast. The successful demonstration of the
L3CCDs ability to collect diagnostic information has shown that the L3CCD is suitable
for diffraction enhanced breast imaging
Role of the dental hospital-based paediatric liaison nurse in safeguarding children
Aim: Service evaluation of our dental hospital paediatric liaison nursing (DH-PLN) service which provides an additional route for information sharing about safeguarding concerns via an agreed pathway for two-way communication with public health nurses.
Method: Retrospective analysis of clinical records of all children referred by DH teams to PLN in the three months October-December 2016.
Results: One hundred and four children were referred; mean age was 6.2 years, 89.4% from Index of Multiple Deprivation (IMD) quintiles 4 and 5, and 70.2% were attending for dental general anaesthesia. The most common referral reason was dental neglect in 66.3%, followed by missed appointments in 50.0%. The PLN checked child health databases and shared information with health visitors and school nurses (46.2% and 53.8% respectively). Feedback retrieved included known child maltreatment risk factors in 7.7%. This prompted additional child protection referrals to children's social services for seven children (6.7%). Dental outcomes six months later were: treatment complete in 50.0%, treatment ongoing 28.8%, discharged to original referrer with treatment incomplete in 21.1%.
Conclusion: This DH-PLN service promotes integrated multidisciplinary working, helping overcome barriers to dentistry's involvement in safeguarding. It facilitates more accurate assessments of risk of harm to children receiving dental care and prompts additional child protection referrals to social services
Children's working understanding of knowledge sources : confidence in knowledge gained from testimony
In three experiments children aged between 3 and 5 years (N = 38; 52; 94; mean ages 3;7 to 5;2) indicated their confidence in their knowledge of the identity of a hidden toy. With the exception of some 3-year-olds, children revealed working understanding of their knowledge source by showing high confidence when they had seen or felt the toy, and lower confidence when they had been told its identity by an apparently well-informed speaker, especially when the speaker subsequently doubted the adequacy of his access to the toy. After a 2-minute delay, 3-to 4- year olds, unlike
4- to 5-year-olds, failed to see the implications of the speaker’s doubt about his access
Efficiency of the Incomplete Enumeration algorithm for Monte-Carlo simulation of linear and branched polymers
We study the efficiency of the incomplete enumeration algorithm for linear
and branched polymers. There is a qualitative difference in the efficiency in
these two cases. The average time to generate an independent sample of
sites for large varies as for linear polymers, but as for branched (undirected and directed) polymers, where
. On the binary tree, our numerical studies for of order
gives . We argue that exactly in this
case.Comment: replaced with published versio
Observed soil moisture impact on strong convection over mountainous Tibetan Plateau
Convection over the Tibetan Plateau (TP) has been linked to heavy rain and flooding in downstream parts of China. Understanding processes which influence the development of convection on the TP could contribute to better forecasting of these extreme events. TP scale (~1000 km) soil moisture gradients have been shown to influence formation of convective systems over the eastern TP. The importance of smaller-scale (~10 km) variability has been identified in other regions (including the Sahel and Mongolia) but has yet to be investigated for the TP. In addition, compared to studies over flat terrain, much less is known about soil moisture–convection feedbacks above complex topography. In this study we use satellite observations of cold cloud, land surface temperature, and soil moisture to analyze the effect of mesoscale soil moisture heterogeneity on the initiation of strong convection in the complex TP environment. We find that strong convection is favored over negative (positive) land surface temperature (soil moisture) gradients. The signal is strongest for less vegetation and low topographic complexity, though still significant up to a local standard deviation of 300 m in elevation, accounting for 65% of cases. In addition, the signal is dependent on background wind. Strong convective initiation is only sensitive to local (tens of kilometers) soil moisture heterogeneity for light wind speeds, though large-scale (hundreds of kilometers) gradients may still be important for strong wind speeds. Our results demonstrate that, even in the presence of complex topography, local soil moisture variability plays an important role in storm development
The CDF dijet excess from intrinsic quarks
The CDF collaboration reported an excess in the production of two jets in
association with a . We discuss constraints on possible new particle state
interpretations of this excess. The fact of no statistically significant
deviation from the SM expectation for {+dijet} events in CDF data disfavors
the new particle explanation. We show that the nucleon intrinsic strange quarks
provide an important contribution to the boson production in association
with a single top quark production. Such {+t} single top quark production
can contribute to the CDF {+dijet} excess, thus the nucleon intrinsic quarks
can provide a possible explanation to the CDF excess in {+dijet} but not in
{+dijet} events.Comment: 4 latex pages, 1 figure. Version for journal publicatio
Rescue of neurological deficits in a mouse model for Angelman Syndrome by reduction of αCaMKII inhibitory phosphorylation
Angelman Syndrome (AS) is a severe neurological disorder characterized by mental retardation, motor dysfunction and epilepsy. We now show that the molecular and cellular deficits of an AS mouse model can be rescued by introducing an additional mutation at the inhibitory phosphorylation site of αCaMKII. Moreover, these double mutants do no longer show the behavioral deficits seen in AS mice, suggesting that these deficits are the direct result of increased αCaMKII inhibitory phosphorylation
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