Optical excitation and external photoluminescence quantum efficiency of Eu3+ in GaN

We investigate photoluminescence of Eu-related emission in a GaN host consisting of thin layers grown by organometallic vapor-phase epitaxy. By comparing it with a reference sample of Eu-doped Y2O3, we find that the fraction of Eu3+ ions that can emit light upon optical excitation is of the order of 1%. We also measure the quantum yield of the Eu-related photoluminescence and find this to reach (similar to 10%) and (similar to 3%) under continuous wave and pulsed excitation, respectively.Stichting voor de Technologische Wetenschappen (STW); Japan Society for the Promotion of Science [19GS1209, 24226009]; Ministry of Education, Culture, Sports, Science and Technology of Japaninfo:eu-repo/semantics/publishedVersio

Effect of air distribution and spray liquid distribution of a cross-flow fan orchard sprayer on spray deposition in fruit trees

In a 4-year ongoing research programme in the Netherlands, we focus to maximise spray deposition in pome fruit trees and minimise spray deposition underneath the trees on the ground and minimise spray drift. For a cross-flow fan orchard sprayer we therefore measured spray deposition in the tree as an effect of different air settings and nozzle types. Nozzle types chosen were the Albuz ATR lilac (as a reference) and the Albuz TVI8001, both sprayed at 7 bar spray pressure. The orchard sprayer was a Munckhof cross-flow fan sprayer with a 2.75 m high cross-flow construction on top of the axial fan, equipped with 8 nozzles on both sides. At a forward speed of 6.5 km/h the spray volume was 200 L/ha and 290 L/ha, for respectively the Albuz lilac and Albuz TVI8001 nozzles. Air settings were: High air setting - 540 rpm PTO; and Low air setting - 540 rpm, 400 rpm, and 300 rpm PTO. Liquid distributions were measured with an AAMS-Salvarani Vertical patternator with discs, and air distribution was measured with a self-constructed measuring device equipped with ultrasonic anemometers and a handheld vane-anemometer. Liquid distribution in the apple trees (cv. Elstar) was measured in the full leaf growing stage (following ISO 22522). First results show a good correlation between air distribution and liquid distribution. Vertical liquid distribution measured on the liquid measuring device correlates also very good with the liquid distribution at different heights in the tree. However, air distribution and especially air speed of the orchard sprayer showed that decreasing air assistance increased the spray deposition in the fruit trees. Showing that air assistance is an important parameter to be taken up in the advice to fruit growers.In a 4-year ongoing research programme in the Netherlands, we focus to maximise spray deposition in pome fruit trees and minimise spray deposition underneath the trees on the ground and minimise spray drift. For a cross-flow fan orchard sprayer we therefore measured spray deposition in the tree as an effect of different air settings and nozzle types. Nozzle types chosen were the Albuz ATR lilac (as a reference) and the Albuz TVI8001, both sprayed at 7 bar spray pressure. The orchard sprayer was a Munckhof cross-flow fan sprayer with a 2.75 m high cross-flow construction on top of the axial fan, equipped with 8 nozzles on both sides. At a forward speed of 6.5 km/h the spray volume was 200 L/ha and 290 L/ha, for respectively the Albuz lilac and Albuz TVI8001 nozzles. Air settings were: High air setting - 540 rpm PTO; and Low air setting - 540 rpm, 400 rpm, and 300 rpm PTO. Liquid distributions were measured with an AAMS-Salvarani Vertical patternator with discs, and air distribution was measured with a self-constructed measuring device equipped with ultrasonic anemometers and a handheld vane-anemometer. Liquid distribution in the apple trees (cv. Elstar) was measured in the full leaf growing stage (following ISO 22522). First results show a good correlation between air distribution and liquid distribution. Vertical liquid distribution measured on the liquid measuring device correlates also very good with the liquid distribution at different heights in the tree. However, air distribution and especially air speed of the orchard sprayer showed that decreasing air assistance increased the spray deposition in the fruit trees. Showing that air assistance is an important parameter to be taken up in the advice to fruit growers

Momentum of an electromagnetic wave in dielectric media

Almost a hundred years ago, two different expressions were proposed for the energy--momentum tensor of an electromagnetic wave in a dielectric. Minkowski's tensor predicted an increase in the linear momentum of the wave on entering a dielectric medium, whereas Abraham's tensor predicted its decrease. Theoretical arguments were advanced in favour of both sides, and experiments proved incapable of distinguishing between the two. Yet more forms were proposed, each with their advocates who considered the form that they were proposing to be the one true tensor. This paper reviews the debate and its eventual conclusion: that no electromagnetic wave energy--momentum tensor is complete on its own. When the appropriate accompanying energy--momentum tensor for the material medium is also considered, experimental predictions of all the various proposed tensors will always be the same, and the preferred form is therefore effectively a matter of personal choice.Comment: 23 pages, 3 figures, RevTeX 4. Removed erroneous factor of mu/mu_0 from Eq.(44

Operationalizing and digitizing person-centered daily functioning:a case for functionomics

An ever-increasing amount of data on a person’s daily functioning is being collected, which holds information to revolutionize person-centered healthcare. However, the full potential of data on daily functioning cannot yet be exploited as it is mostly stored in an unstructured and inaccessible manner. The integration of these data, and thereby expedited knowledge discovery, is possible by the introduction of functionomics as a complementary ‘omics’ initiative, embracing the advances in data science. Functionomics is the study of high-throughput data on a person’s daily functioning, that can be operationalized with the International Classification of Functioning, Disability and Health (ICF). A prerequisite for making functionomics operational are the FAIR (Findable, Accessible, Interoperable, and Reusable) principles. This paper illustrates a step by step application of the FAIR principles for making functionomics data machine readable and accessible, under strictly certified conditions, in a practical example. Establishing more FAIR functionomics data repositories, analyzed using a federated data infrastructure, enables new knowledge generation to improve health and person-centered healthcare. Together, as one allied health and healthcare research community, we need to consider to take up the here proposed methods.</p

Transport properties of copper phthalocyanine based organic electronic devices

Ambipolar charge carrier transport in Copper phthalocyanine (CuPc) is studied experimentally in field-effect transistors and metal-insulator-semiconductor diodes at various temperatures. The electronic structure and the transport properties of CuPc attached to leads are calculated using density functional theory and scattering theory at the non-equilibrium Green's function level. We discuss, in particular, the electronic structure of CuPc molecules attached to gold chains in different geometries to mimic the different experimental setups. The combined experimental and theoretical analysis explains the dependence of the mobilityand the transmission coefficient on the charge carrier type (electrons or holes) and on the contact geometry. We demonstrate the correspondence between our experimental results on thick films and our theoretical studies of single molecule contacts. Preliminary results for fluorinated CuPc are discussed.Comment: 18 pages, 16 figures; to be published in Eur. Phys. J. Special Topic

In-depth molecular analysis of combined and co-primary pulmonary large cell neuroendocrine carcinoma and adenocarcinoma

Up to 14% of large cell neuroendocrine carcinomas (LCNECs) are diagnosed in continuity with nonsmall cell lung carcinoma. In addition to these combined lesions, 1% to 7% of lung tumors present as co-primary tumors with multiple synchronous lesions. We evaluated molecular and clinicopathological characteristics of combined and co-primary LCNEC-adenocarcinoma (ADC) tumors. Ten patients with LCNEC-ADC (combined) and five patients with multiple synchronous ipsilateral LCNEC and ADC tumors (co-primary) were included. DNA was isolated from distinct tumor parts, and 65 cancer genes were analyzed by next generation sequencing. Immunohistochemistry was performed including neuroendocrine markers, pRb, Ascl1 and Rest. Pure ADC (N = 37) and LCNEC (N = 17) cases were used for reference. At least 1 shared mutation, indicating tumor clonality, was found in LCNEC- and ADC-parts of 10/10 combined tumors but only in 1/5 co-primary tumors. A range of identical mutations was observed in both parts of combined tumors: 8/10 contained ADC-related (EGFR/KRAS/STK11 and/or KEAP1), 4/10 RB1 and 9/10 TP53 mutations. Loss of pRb IHC was observed in 6/10 LCNEC- and 4/10 ADC-parts. The number and intensity of expression of Ascl1 and neuroendocrine markers increased from pure ADC (low) to combined ADC (intermediate) and combined and pure LCNEC (high). The opposite was true for Rest expression. In conclusion, all combined LCNEC-ADC tumors were clonally related indicating a common origin. A relatively high frequency of pRb inactivation was observed in both LCNEC- and ADC-parts, suggesting an underlying role in LCNEC-ADC development. Furthermore, neuroendocrine differentiation might be modulated by Ascl1(+) and Rest(-) expression

Semantics in active surveillance for men with localized prostate cancer - results of a modified Delphi consensus procedure

Active surveillance (AS) is broadly described as a management option for men with low-risk prostate cancer, but semantic heterogeneity exists in both the literature and in guidelines. To address this issue, a panel of leading prostate cancer specialists in the field of AS participated in a consensus-forming project using a modified Delphi method to reach international consensus on definitions of terms related to this management option. An iterative three-round sequence of online questionnaires designed to address 61 individual items was completed by each panel member. Consensus was considered to be reached if >= 70% of the experts agreed on a definition. To facilitate a common understanding among all experts involved and resolve potential ambiguities, a face-to-face consensus meeting was held between Delphi survey rounds two and three. Convenience sampling was used to construct the panel of experts. In total, 12 experts from Australia, France, Finland, Italy, the Netherlands, Japan, the UK, Canada and the USA participated. By the end of the Delphi process, formal consensus was achieved for 100% (n = 61) of the terms and a glossary was then developed. Agreement between international experts has been reached on relevant terms and subsequent definitions regarding AS for patients with localized prostate cancer. This standard terminology could support multidisciplinary communication, reduce the extent of variations in clinical practice and optimize clinical decision making.Peer reviewe

Removing orientation-induced localization biases in single-molecule microscopy using a broadband metasurface mask

Nanoscale localization of single molecules is a crucial function in several advanced microscopy techniques, including single-molecule tracking and wide-field super-resolution imaging. Until now, a central consideration of such techniques is how to optimize the precision of molecular localization. However, as these methods continue to push towards the nanometre size scale, an increasingly important concern is the localization accuracy. In particular, single fluorescent molecules emit with an anisotropic radiation pattern of an oscillating electric dipole, which can cause significant localization biases using common estimators. Here we present the theory and experimental demonstration of a solution to this problem based on azimuthal filtering in the Fourier plane of the microscope. We do so using a high-efficiency dielectric metasurface polarization/phase device composed of nanoposts with subwavelength spacing. The method is demonstrated both on fluorophores embedded in a polymer matrix and in dL5 protein complexes that bind malachite green

Engineering Schottky contacts in open-air fabricated heterojunction solar cells to enable high performance and ohmic charge transport.

The efficiencies of open-air processed Cu2O/Zn(1-x)Mg(x)O heterojunction solar cells are doubled by reducing the effect of the Schottky barrier between Zn(1-x)Mg(x)O and the indium tin oxide (ITO) top contact. By depositing Zn(1-x)Mg(x)O with a long band-tail, charge flows through the Zn(1-x)Mg(x)O/ITO Schottky barrier without rectification by hopping between the sub-bandgap states. High current densities are obtained by controlling the Zn(1-x)Mg(x)O thickness to ensure that the Schottky barrier is spatially removed from the p-n junction, allowing the full built-in potential to form, in addition to taking advantage of the increased electrical conductivity of the Zn(1-x)Mg(x)O films with increasing thickness. This work therefore shows that the Zn(1-x)Mg(x)O window layer sub-bandgap state density and thickness are critical parameters that can be engineered to minimize the effect of Schottky barriers on device performance. More generally, these findings show how to improve the performance of other photovoltaic system reliant on transparent top contacts, e.g., CZTS and CIGS.This work was supported by EPSRC of the UK (award number RG3717)This is the accepted manuscript. The final version is available from ACS at http://pubs.acs.org/doi/abs/10.1021/am5058663