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In the 2015 review paper ‘Petawatt Class Lasers Worldwide’ a comprehensive overview of the current status of high-power facilities of
was presented. This was largely based on facility specifications, with some description of their uses, for instance in fundamental ultra-high-intensity interactions, secondary source generation, and inertial confinement fusion (ICF). With the 2018 Nobel Prize in Physics being awarded to Professors Donna Strickland and Gerard Mourou for the development of the technique of chirped pulse amplification (CPA), which made these lasers possible, we celebrate by providing a comprehensive update of the current status of ultra-high-power lasers and demonstrate how the technology has developed. We are now in the era of multi-petawatt facilities coming online, with 100 PW lasers being proposed and even under construction. In addition to this there is a pull towards development of industrial and multi-disciplinary applications, which demands much higher repetition rates, delivering high-average powers with higher efficiencies and the use of alternative wavelengths: mid-IR facilities. So apart from a comprehensive update of the current global status, we want to look at what technologies are to be deployed to get to these new regimes, and some of the critical issues facing their development.
Thin hole transport layers are important elements in organic semiconductor-based devices. Metal oxides are an encouraging material class for this purpose, as they may provide sufficient hole conduction in combination with excellent electron blocking properties. Both, long-term device stability, which may often be limited by the thermal stability of interfaces, and higher temperature processing steps, benefit strongly from the existence of thermally stable metal oxide interlayers. Provided that thermally stable electrodes can be fashioned, the stability of organic active layers—for example, in organic field effect transistors, light emitting diodes, or photovoltaic (OPV) devices can be investigated. Here, we apply this concept and report about the study of hole mobility (µh) in single-carrier-hole-only devices in dependence of thermal annealing up to the above the actual melting temperature of regio-regular poly(3-hexylthiophene-2,5-diyl) (P3HT).
The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals’ species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR for Bartonella spp. based on nuoG gene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained for Bartonella (nuoG) (n = 3), gltA (n = 2), rpoB (n = 1), ftsZ (n = 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, the Bartonella sequences clustered with Bartonella genotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation of Bartonella spp. and hemoplasmas among bats in Brazil.
Though during the last years of his life Richard Stanyhurst, best known to English literature for his early translation of Virgil's Aeneid, was one of the chaplains to the court of Albert and Isabel, the exact time of his appointment has not, so far as I can ascertain, been known. Two registers in the General archives at Brussels containing Albert's household accounts for the years 1612 to 1618 (Chamhre des Comptes 1837 and 1838), give us much more precise information on this subject. They not only record current salary payments from September 1612 onwards hut tell us retrospectively in 1618, the year of his death, that he assumed his duties as chaplain on 29 June 1607 and suggest that as late as 2 July 1618 he was alive hut his death was probably imminent.
The Calar Alto Deep Imaging Survey (CADIS) combines deep multicolor imaging in broad and narrow band filters with deep probing in several selected wavelength intervals through a Fabry-Pérot (FP) interferometer with a spectral resolution of ∼450.
Open-pollinated (OPs) and composite populations (CPs) represent a valuable resource for sunflower breeding programmes. However, little is known about the levels and distribution of genetic variation within each of these populations. In this study, quantitative and qualitative traits along with molecular markers were used to evaluate 14 populations from the Instituto Nacional de Tecnología Agropecuaria (INTA) sunflower germplasm collection. These populations were chosen to represent historically important accessions that still play a central role within the INTA sunflower breeding programme due to their extensive variation in diverse agronomically important traits. Nine quantitative and eight qualitative agro-morphological descriptors were recorded and compared with those of a larger set of accessions representative of the phenotypic diversity of the sunflower collection. Molecular characterization was conducted on a total of 311 individuals using 16 microsatellite markers. Overall, the average gene diversity was 0.56 and the average number of alleles per locus was 6.25. No statistically significant differences in genetic diversity were detected between the OPs and CPs. Global estimates of FST revealed very high levels of differentiation among accessions (FST= 0.413, P< 0.05). Population structure analyses were consistent with the observed levels of differentiation and identified two major groups. The results of this work show that high global diversity is preserved within the accessions analysed here. Additionally, this study provides a set of reliable and discriminant markers for the cost-effective molecular characterization of sunflower accessions, along with the guidelines for the delineation of sampling strategies for OPs and CPs, thus aiding the efficient management and exploitation of sunflower germplasm collections.
Primitive meteorites contain small amounts of presolar minerals that formed in the winds of evolved stars or in the ejecta of stellar explosions. Silicon carbide is the best studied presolar mineral. Based on its isotopic compositions it was divided into distinct populations that have different origins: Most abundant are the mainstream grains which are believed to come from 1.5–3 M⊙ AGB stars of roughly solar metallicity. The rare Y and Z grains are likely to come from 1.5–3 M⊙ AGB stars as well, but with subsolar metallicities (0.3–0.5 times solar). Here we report on C and Si isotope and trace element (Zr, Ba) studies of individual, submicrometer-sized SiC grains. The most striking results are: (1) Zr and Ba concentrations are higher in Y and Z grains than in mainstream grains, with enrichments relative to Si and solar of up to 70 times (Zr) and 170 times (Ba), respectively; (2) For the Y and Z grains there is a positive correlation between Ba concentrations and amount of s-process Si. This correlation is well explained by predictions for 2–3 M⊙ AGB stars with metallicities of 0.3–0.5 times solar. This confirms low-metallicity stars as most likely stellar sources for the Y and Z grains.
This paper aims at a general guideline to obtain a posteriori error estimates for the finite element error control in computational partial differential equations. In the abstract setting of mixed formulations, a generalised formulation of the corresponding residuals is proposed which then allows for the unified estimation of the respective dual norms. Notably, this can be done with an approach which is applicable in the same way to conforming, nonconforming and mixed discretisations. Subsequently, the unified approach is applied to various model problems. In particular, we consider the Laplace, Stokes, Navier-Lamé, and the semi-discrete eddy current equations.
We prepared a carbon nitride compound by treating the molecular precursor C2N4H4 in a laser-heated diamond-anvil-cell (LH-DAC) at pressures exceeding 27 GPa and temperatures above 1700°C. After quenching we recovered single crystals of the new material with diameters of about 1 μm. Using several experimental characterization techniques in conjunction with computational methods we determined composition, hybridization of constituting atoms, and the crystal structure. The new carbon nitride imide, C2N2(NH), adopts a defect-wurtzite structure and is isotypic to Si2N2(NH).
Bimetallic glycolato silicates of the form M2 Si2(OCH2CH2O)5 where M is an alkali metal, can be synthesized directly from SiO2, ethylene glycol and MOH. Further reaction with HO(CH2CH2O)4H, PEG4, transforms these compounds into rheologically useful polymers. These polymers offer considerable potential for processing novel silicate glass shapes, e.g. thin films, fibers and membranes, from relatively inexpensive precursors materials. In this paper, we describe pyrolysis studies on the model compound Li2 Si2(OCH2CH2O)5 as a prelude to determing the utility of the polymeric precursors. These studies delineate the effects of temperature on the decomposition processes whereby the glycolato silicate transforms into almost phase pure, crystalline Li2O-2SiO2. This work is contrasted with previous pyrolysis studies on K2 Si2(OCH2CH2O)5.
The reaction of SiO2 with basic magnesium compounds, in the presence of excess ethylene glycol, provides access to the hexacoordinate silicate complex, MgSi(OCH2CH2O)3. Alkali metal hydroxides provide access to pentacoordinate silicates of the type M2Si2(OCH2CH2O)5, where M = Li, Na, K, and Cs. Alumina also reacts with alkali metal hydroxides and ethylene glycol to give compounds of the type MAI(OCH2CH2O)2. HCl neutralization of the alkali metal silicates and aluminates provides the neutral metal glycolates of Si and Al. Stoichiometrically correct mixtures of these complexes form homogeneous, cordierite precursor solutions that are potentially useful for forming films, fibers and membranes of cordierite. These polymer-like materials can be heated directly in air to generate first α-cordierite and then µ-cordierite. Hydrolysis and condensation reactions, which occur in sol-gel processing, are not required. The phase transformations and chemical changes that occur during pyrolytic transformation of the preceramic materials to their target ceramic products were characterized. Methods developed during the course of these studies led to the development of heating schedules wherein well crystallized g.-cordierite could be formed at 850 °C.
We develop and analyze an adaptive hybridized Interior Penalty Discontinuous Galerkin (IPDG-H) method for H(curl)-elliptic boundary value problems in 2D or 3D arising from a semi-discretization of the eddy currents equations. The method can be derived from a mixed formulation of the given boundary value problem and involves a Lagrange multiplier that is an approximation of the tangential traces of the primal variable on the interfaces of the underlying triangulation of the computational domain. It is shown that the IPDG-H technique can be equivalently formulated and thus implemented as a mortar method. The mesh adaptation is based on a residual-type a posteriori error estimator consisting of element and face residuals. Within a unified framework for adaptive finite element methods, we prove the reliability of the estimator up to a consistency error. The performance of the adaptive symmetric IPDG-H method is documented by numerical results for representative test examples in 2D.
Recently etched heavy ion tracks in MOS devices were filled with (semi)conducting materials to enable charge extraction from, or injection into the conducting channel below the Si/oxide interface, respectively. This leads to a family of novel electronic devices that we denoted as “TEMPOS” structures - that acronym stands for “Tunable Electronic Material with Pores in Oxide on Silicon”. In comparison with MOS-FETs, TEMPOS structures have some unique properties due to their additional parameters such as the track diameter, density, and shape, and the material embedded therein and its spatial distribution. This makes these novel structures much more complex, and it eventually leads to higher compactation of the TEMPOS circuits and to unexpected electronic properties. Depending on the choice of these parameters and the working point of these structures, TEMPOS elements can overtake the function of gatable resistors, condensors, photocells, hygrocells, diodes, sensors, and others. This work concentrates on some basic aspects of TEMPOS and gives some corresponding current /voltage relations and equivalent circuits.
Neck abscesses can originate from congenital cervical cysts. Cervical cysts of bronchogenic origin are rare and often asymptomatic. Common symptoms of bronchogenic cysts are stridor, dyspnoea and dysphagia. The reported patient represents the second published case of a bronchogenic cyst causing a neck abscess in an adult.
We report a case of a cervical bronchogenic cyst presenting as a recurrent supraclavicular abscess in a middle-aged woman. During extirpation, a fistula was demonstrated to the right upper lobe of the lung, suspected because the cyst inflated synchronously with respiration.
The symptoms of bronchogenic cysts are due to the effects of compression or fistulas. In the majority of these cysts, a thorough investigation involving history, examination and radiological imaging does not clearly demonstrate a fistula. Therefore, extirpation is both diagnostic and therapeutic.
A bronchogenic cyst is a very rare cause of a recurrent deep neck abscess. Total extirpation is the treatment of choice.
To describe a pseudo-outbreak of Clostridium difficile infection (CDI) caused by a faulty toxin assay lot and to determine the effect of sensitivity, specificity, and repeated testing for C. difficile on perceived CDI burden, positive predictive value, and false-positive results.
Outbreak investigation and criterion standard.
Patients hospitalized at a tertiary care hospital who had at least 1 toxin assay for detection of C. difficile performed during the period from July 1, 2004, through June 30, 2006.
The run control chart method and the x2 test were used to compare CDI rates and the proportion of positive test results before, during, and after the pseudo-outbreak. The effect of repeated testing was evaluated by using 3 hypothetical models with a sample of 10,000 patients and various assay sensitivity and specificity estimates.
In November of 2005, the CDI rate at the hospital increased from 1.5 to 2.6 cases per 1,000 patient-days (P< .01), and the proportion of positive test results increased from 13.6% to 22.1% (P< .01). An investigation revealed a pseudo-outbreak caused by a faulty toxin assay lot. A decrease of only 1.2% in the specificity of the toxin assay would result in a 32% increase in perceived incidence of CDI at this institution. When calculated by use of the manufacturer's stated specificity and sensitivity and this institution's testing practices, the positive predictive value of the test decreased from 80.6% to 4.1% for patients who received 3 tests.
Specificity is as important as sensitivity when testing for CDI. False-positive CDI cases can drain hospital resources and adversely affect patients. Repeated testing for C. difficile should be performed with caution.
Amortization of a shock in an electro-rheological shock absorber is carried out in the motion of a piston in an electrorheological fluid. The drag force acting on the piston is regulated by varying the voltage applied to electrodes. A model of an electrorheological shock absorber is constructed. A problem on shock absorber reduces to the solution of a coupled problem for motion equation of the piston and non-linear equations of fluid flow in an unknown domain that varies with the time. A method of semi-discretization for approximate solution of the coupled problem is considered. Results on the existence and on the uniqueness of the solution of the coupled problem are obtained. Convergence of approximate solutions to the exact solution is proved. Numerical simulation of the operation of the shock absorber is performed.
The aim of this study was to characterize impairments of hand function in individuals with myelomeningocele (MMC) using a quantitative method. A grip–lift task was studied in 29 individuals with MMC (17 females, 12 males; mean age 12 years 4 months, SD 5 years 6 months; range 4 to 28 years) and 29 age- and sex-matched control participants. A small object (weight 200g) was grasped and lifted with a precision grip of the dominant hand and grip forces (GF) and time intervals were measured. Sensibility was examined with a two-point discrimination test. In those with MMC, the latency between GF onset of the thumb and index finger and ensuing preload duration were both significantly prolonged (p<0.01). Fingertip forces were excessively high and variable. Several parameters differed significantly between those with MMC and control individuals: GF peak, GF at start of loading, mean GF, and the SDs of the GF during static holding. Although the two-point discrimination task indicated deficits of sensibility, these did not correlate with grip force parameters. Results demonstrate that fine motor skills in patients with MMC are impeded by slowness and inadequate adjustments of manipulative forces.