Generalised Wick Transform in Dimensionally Reduced Gravity

In the context of canonical quantum gravity, we study an alternative real quantisation scheme, which is arising by relating simpler Riemannian quantum theory to the more complicated physical Lorentzian theory - the generalised Wick transform. On the symmetry reduced models, homogenous Bianchi cosmology and 2+1 gravity, we investigate its generalised construction principle, demonstrate that the emerging quantum theory is equivalent to the one obtained from standard quantisation and how to obtain physical states in Lorentzian gravity from Wick transforming solutions of Riemannian quantum theory.Comment: 25 pages, 3 figures, revtex4; v.2: referencing improve

PARTICLE VELOCITY MEASUREMENT BY HOLOGRAPHY

A double pulsed holography was used to measure the particle velocity and velocity distribution. Semiautomatic technique has been developed at the Department of Physics, Technical University Budapest and used to evaluate the hologram. The velocity of the particle at all points in the sample volume can be measured with high accuracy

Electrical and optical characteristics of hydrogen-plasma treated ZnO nanoneedles

We report on optical characteristics as well as electron emission of hydrogen-plasma treated ZnO nanoneedle arrays. The nanoneedle arrays were vertically grown on Si substrates using catalyst-free metalorganic chemical vapor deposition and subsequently treated by hydrogen plasma at room temperature. After hydrogen plasma treatment, the field emission characteristic curves of nanoneedle arrays exhibited significantly reduced turn-on field and increased emission current density, and the electrical conductivity was increased. In addition, low temperature photoluminesence (PL) measurements indicate that a neutral-donor bound exciton PL peak intensity was increased by the hydrogen- plasma treatment. These effects of the plasma treatment on the physical properties may be explained in terms of hydrogen doping effect. (c) 2005 American Vacuum Society.open112224sciescopu

Source of tubercle bacilli in cervical lymph nodes: A prospective study

A prospective study searching for associated mycobacterial infection of the upper aerodigestive tract in patients with cervical tuberculous lymphadenitis (TBLN) was carried out. One hundred and thirteen patients with a clinical suspicion of cervical TBLN were included. All patients had a physical examination of the upper aerodigestive tract. Routine endoscopy and biopsy of the nasopharynx were performed. All of them had surgery to the cervical lymph node. Seventy-five patients had histologically confirmed cervical TBLN. Culture of the lymph node specimen showed Mycobacterium tuberculosis in 68 (90 per cent). In 45 (60 per cent) patients with cervical TBLN the primary foci of infection could not be found. Twenty-nine (39 per cent) had radiographic evidence of active or healed pulmonary tuberculosis. Sputum culture from two patients showed Mycobacterium tuberculosis. Five patients (six per cent) had tuberculous nasopharyngitis. In one of them (one per cent) the tuberculous nasopharyngitis was primary as no other evidence of mycobacterial infection was found. In the present study, mycobacterial infection of other parts of the upper aerodigestive tract was not found.published_or_final_versio

Intracranial hypotension secondary to spinal arachnoid cyst rupture presenting with acute severe headache: a case report

<p>Abstract</p> <p>Introduction</p> <p>Headache is a common presenting complaint and has a wide differential diagnosis. Clinicians need to be alert to clues that may suggest an underlying secondary aetiology. We describe a novel case of headache secondary to intracranial hypotension which was precipitated by the rupture of a spinal arachnoid cyst.</p> <p>Case report</p> <p>A 51-year-old Indian female presented with sudden onset severe headache suggestive of a subarachnoid haemorrage. Investigations including a computed tomography brain scan, cerebrospinal fluid examination and a magnetic resonance angiogram were normal. The headache persisted and magnetic resonance imaging revealed bilateral thin subdural collections, a spinal subarachnoid cyst and a right-sided pleural effusion. This was consistent with a diagnosis of headache secondary to intracranial hypotension resulting from spinal arachnoid cyst rupture.</p> <p>Conclusions</p> <p>Spinal arachnoid cyst rupture is a rare cause of spontaneous intracranial hypotension. Spontaneous intracranial hypotension is a common yet under-diagnosed heterogeneous condition. It should feature significantly in the differential diagnosis of patients with new-onset daily persistent headache.</p