81 research outputs found

    The phase sensitivity of a fully quantum three-mode nonlinear interferometer

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    We study a nonlinear interferometer consisting of two consecutive parametric amplifiers, where all three optical fields (pump, signal and idler) are treated quantum mechanically, allowing for pump depletion and other quantum phenomena. The interaction of all three fields in the final amplifier leads to an interference pattern from which we extract the phase uncertainty. We find that the phase uncertainty oscillates around a saturation level that decreases as the mean number NN of input pump photons increases. For optimal interaction strengths, we also find a phase uncertainty below the shot-noise level and obtain a Heisenberg scaling 1/N1/N. This is in contrast to the conventional treatment within the parametric approximation, where the Heisenberg scaling is observed as a function of the number of down-converted photons inside the interferometer.Comment: 8 pages, 7 figure

    VIRUSES OF SOME GARLIC ECOTYPES IN CROATIA

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    Recent, there is increasing demand for autochthonous ecotypes of garlic (Allium sativum L.) in Croatia. Many local ecotypes of garlic are developed due to specific environmental conditions and producer's selection. However, the average yield of garlic is not in the European average range, since the classical vegetative propagation from cloves usually results with virus infections that cause significant yield reduction. Viruses are considered significant garlic’s pathogens. The research was set up to determine infection rate in plant material of different garlic ecotypes grown from cloves in different regions. Plants were collected from commercial fields in Zadar County (coastal part of Croatia) and Vukovar-Srijem County (eastern Croatia) and were tested by enzyme-linked immunosorbent assay (ELISA) on the presence of three viruses: Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV) and Garlic common latent virus (GCLV). As a potential source ofantigen leaf tissue was used and tests were conducted according to manufacturer’s instructions (Bioreba AG, Switzerland). In plants from Zadar County dominant was OYDV, followed by GCLV and LYSV. All tested plants originating from Vukovar-Srijem County were infected with three tested viruses. Out of 316 analyzed plants only 4 (1.3%) showed to be free from viruses included in survey. Plants infected with OYDV showed symptoms of leaf yellowing and reduced growth, while those infected with LYSV expressed yellow stripes. Symptoms were most evident at the beginning of vegetation. Due to high infection rate, deteriorated sanitary status, and increased interest in use and production of local garlic ecotypes, work on sanitary selection will be important part of revitalization program

    Magnetic resonance imaging diagnosis of causes of cerebral palsy in a developing country: A database of South African children

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    Background. Cerebral palsy (CP) is a common worldwide disabling disorder. However, data about prevalence and causes of CP in developing countries are deficient because of high cost and limited availability of magnetic resonance imaging (MRI), the gold standard neuro-imaging modality for evaluation and management of CP in neonates. Objectives. To determine the frequency of CP causes in children with suspected hypoxic ischaemic injury (HII) involved in medicolegal litigation in South Africa based on MRI report findings. Methods. A total of 1 620 MRI reports were categorised into HII, non-HII and normal MRI. None of the patients had prior neuro-imaging records. HII reports were sub-classified according to pattern of brain injury into basal ganglia-thalamus (BGT), watershed (WS), combined BGT-WS, periventricular leukomalacia (PVL) and multicystic encephalomalacia. Non-HII diagnoses were sub-classified into strokes, congenital malformations, kernicterus, hydrocephalus, haemorrhages, atrophies, metabolic causes and infections. Results. The median age was 6 years. HII reports (n=1 233; 76.1%) showed BGT in 447 (27.6%), WS in 266 (16.4%), combined BGT-WS in 335 (20.7%), PVL in 58 (3.6%) and multicystic in 127 (7.8%). Non-HII diagnoses (n=255; 15.7%) showed 78 (4.8%) congenital malformations, 50 (3.1%) atrophies, 35 (2.1%) kernicterus, 23 (1.4%) strokes, 12 (0.8%) haemorrhages, 14 (0.9%) hydrocephalus, 36 (2.1%) metabolic and 7 (0.5%) infections. Normal exams were 132 (8.2%). Conclusions. Despite being performed a relatively long time – median of 6 years – after the suspected perinatal HII, MRI yielded a diagnosis in 92% and showed that only 76% were due to HII, and more importantly, that there was a preterm HII pattern of injury in 15%, which when added to the 16% of non-HII cases, could potentially save on litigation in a total of 31% of cases that are unlikely to be related to malpractice. MRI should be performed wherever possible in CP cases, even if no imaging exam was performed in the perinatal period

    trans-Dichloridobis(2-methyl­aniline-κN)palladium(II)

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    In the title compound, [PdCl2(C7H9N)2], the Pd atom is situated on an inversion centre and displays a distorted square-planar coordination environment. The crystal structure displays weak inter­molecular N—H⋯Cl hydrogen bonding
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