Campbell, B. C.V. et al. (2019) Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data.ABSTRACT Background: CT-perfusion (CTP) and MRI may assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of ischaemic core and penumbra volumes were associated with functional outcomes and treatment effect.

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Effects of stoichiometry on electrical, optical, and structural properties of indium nitride J. Appl. Phys. 98, 093712 (2005); 10.1063/1.2130514Defect formation and annealing behavior of InP implanted by low-energy 15 N ions Elastic recoil detection analysis, using an incident beam of 200 MeV Au ions, has been used to measure indium nitride films grown by radio-frequency sputtering. It is shown that the films have nitrogen-rich stoichiometry. Nitrogen vacancies are therefore unlikely to be responsible for the commonly observed high background carrier concentration. Ultraviolet Raman and secondary ion mass spectroscopy measurements are used to probe the state of the excess nitrogen. The nitrogen on indium anti-site defect is implicated, though other possibilities for the site of the excess nitrogen, such as molecular nitrogen, or di-nitrogen interstitials cannot be excluded. It is further shown that a shift in the ͑0002͒ x-ray diffraction peak correlates with the excess nitrogen, but not with the oxygen observed in some samples.

What are diatoms? Diatoms are a small plant like creature that live in aqueous environments. They have been studied for well over two centuries by biologists, and their remains have been found in large deposits of diatomaceous earth, which is mined for water filtration and housing insulation, among other uses. One of the more unusual properties of these diatoms is that they produce an amorphous silica shell or "frustule" which is nano-porous. There are thousands of diatom species with a commensurate variety of frustule form and pore type. The pores in diatom valves range in diameter from > 1µm to < 10 nm [1]. Figures 1,2 and 3 show example secondary electron micrographs of some of the diatoms examined here. Why study diatoms? Interest in porous semiconductor and insulating materials has developed from the realisation that porous silicon luminesces efficiently in the visible region when irradiated with ultraviolet light [2]. Porous silica was originally investigated in an attempt to elucidate the mechanism of luminescence for porous silicon. However, porous silica has since been found to have its own unique properties and is now used in a number commercial applications [3][4][5][6]. In particular we note that porous silica has been used for novel optical fiber based photonic devices [7] and more recently as a matrix for high quantum efficiency nanoparticle luminescence devices [8,9]. Diatoms are another form of porous silica. The equivalent potential of diatoms for optoelectronic and photonic device applications is examined here by studying the luminescence properties of a number of different types of diatom. These include fresh water benthic diatoms collected from streams, and cultured diatoms from the University of Ghent.

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ObjectiveTo summarise evidence of the effects of blood pressure (BP)-lowering interventions after acute spontaneous intracerebral haemorrhage (ICH).MethodsA prespecified systematic review of the Cochrane Central Register of Controlled Trials, EMBASE and MEDLINE databases from inception to 23 June 2020 to identify randomised controlled trials that compared active BP-lowering agents versus placebo or intensive versus guideline BP-lowering targets for adults <7 days after ICH onset. The primary outcome was function (distribution of scores on the modified Rankin scale) 90 days after randomisation. Radiological outcomes were absolute (>6 mL) and proportional (>33%) haematoma growth at 24 hours. Meta-analysis used a one-stage approach, adjusted using generalised linear mixed models with prespecified covariables and trial as a random effect.ResultsOf 7094 studies identified, 50 trials involving 11 494 patients were eligible and 16 (32.0%) shared patient-level data from 6221 (54.1%) patients (mean age 64.2 [SD 12.9], 2266 [36.4%] females) with a median time from symptom onset to randomisation of 3.8 hours (IQR 2.6–5.3). Active/intensive BP-lowering interventions had no effect on the primary outcome compared with placebo/guideline treatment (adjusted OR for unfavourable shift in modified Rankin scale scores: 0.97, 95% CI 0.88 to 1.06; p=0.50), but there was significant heterogeneity by strategy (pinteraction=0.031) and agent (pinteraction<0.0001). Active/intensive BP-lowering interventions clearly reduced absolute (>6 ml, adjusted OR 0.75, 95%CI 0.60 to 0.92; p=0.0077) and relative (≥33%, adjusted OR 0.82, 95%CI 0.68 to 0.99; p=0.034) haematoma growth.InterpretationOverall, a broad range of interventions to lower BP within 7 days of ICH onset had no overall benefit on functional recovery, despite reducing bleeding. The treatment effect appeared to vary according to strategy and agent.PROSPERO registration numberCRD42019141136.

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The band-gap of indium nitride has long been believed to be about 1.9eV with slight variations due to band-tailing in polycrystalline samples and degenerate doping. Recently, other values as low as 0.7 eV have apparently been observed. We have compared samples spanning this apparent range of band-gap using secondary ion mass spectroscopy (SIMS), X-ray Photoelectron Spectroscopy (XPS) and heavy ion elastic recoil detection analysis (ERDA), in conjunction with spectral optical density measurements. Once structural inhomogeneiteies are taken into account, we show that much of the conflicting data are compatible with direct photoionisation with a threshold energy of about 1.0eV. This feature was first reported in polycrystalline indium nitride over 15 years ago and attributed to a ∣p> like defect state. We ask whether the feature may instead be a direct band-gap.