Lorentz shift measurements in heavily irradiated silicon detectors in high magnetic fields

An external magnetic field exerts a Lorentz force on drifting electric charges inside a silicon strip sensor and thus shifts the cluster position of the collected charge. The shift can be related to the Lorentz angle which is typically a few degrees for holes and a few tens of degrees for electrons in a 4 T magnetic field. The Lorentz angle depends upon magnetic field, electric field inside the sensor and temperature. In this study the sensitivity to radiation for fluences up to 10^16 n/cm^2 has been studied. The Lorentz shift has been measured by inducing ionization with 670 nm red or 1070 nm infrared laser beams injected into the back side of the irradiated silicon sensor operated in magnetic fields up to 8 T. For holes the shift as a function of radiation is increasing, while for electrons it is decreasing and even changes sign. The fact that for irradiated sensors the Lorentz shift for electrons is smaller than for holes, in contrast to the observations in non-irradiated sensors, can be qualitatively explained by the structure of the electric field in irradiated sensors.Comment: Accepted publication for RD09 conference in Proceedings of Scienc

A 2:1 cocrystal of 6,13-dihydropentacene and pentacene

6,13-Dihydropentacene and pentacene cocrystallize in a ratio of 2:1, i.e. C22H16·0.5C22H14, during vapour transport of commercial pentacene in a gas flow. The crystal structure is monoclinic, space group P21/n, and contains one dihydropentacene molecule and half a pentacene molecule in the asymmetric unit.

Broadband hyperspectral imaging for breast tumor detection using spectral and spatial information

Complete tumor removal during breast-conserving surgery remains challenging due to the lack of optimal intraoperative margin assessment techniques. Here, we use hyperspectral imaging for tumor detection in fresh breast tissue. We evaluated different wavelength ranges and two classification algorithms; a pixel-wise classification algorithm and a convolutional neural network that combines spectral and spatial information. The highest classification performance was obtained using the full wavelength range (450-1650nm). Adding spatial information mainly improved the differentiation of tissue classes within the malignant and healthy classes. High sensitivity and specificity were accomplished, which offers potential for hyperspectral imaging as a margin assessment technique to improve surgical outcome. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen

Towards a Casimir force measurement between micromachined parallel plate structures

Ever since its prediction, experimental investigation of the Casimir force has been of great scientific interest. Many research groups have successfully attempted quantifying the force with different device geometries; however, measurement of the Casimir force between parallel plates with sub-micron separation distance is still a challenging task, since it becomes extremely difficult to maintain sufficient parallelism between the plates. The Casimir force can significantly influence the operation of micro devices and to realize reliable and reproducible devices it is necessary to understand and experimentally verify the influence of the Casimir force at sub-micron scale. In this paper, we present the design principle, fabrication and characterization of micromachined parallel plate structures that could allow the measurement of the Casimir force with tunable separation distance in the range of 100 to 1000 nm. Initially, a gold coated parallel plate structure is explored to measure the Casimir force, but also other material combinations could be investigated. Using gold-silicon eutectic bonding, a reliable approach to bond chips with integrated suspended plates together with a well-defined separation distance in the order of 1–2 μm is developed

Method for coregistration of optical measurements of breast tissue with histopathology : the importance of accounting for tissue deformations

For the validation of optical diagnostic technologies, experimental results need to be benchmarked against the gold standard. Currently, the gold standard for tissue characterization is assessment of hematoxylin and eosin (H&E)-stained sections by a pathologist. When processing tissue into H&E sections, the shape of the tissue deforms with respect to the initial shape when it was optically measured. We demonstrate the importance of accounting for these tissue deformations when correlating optical measurement with routinely acquired histopathology. We propose a method to register the tissue in the H&E sections to the optical measurements, which corrects for these tissue deformations. We compare the registered H&E sections to H&E sections that were registered with an algorithm that does not account for tissue deformations by evaluating both the shape and the composition of the tissue and using microcomputer tomography data as an independent measure. The proposed method, which did account for tissue deformations, was more accurate than the method that did not account for tissue deformations. These results emphasize the need for a registration method that accounts for tissue deformations, such as the method presented in this study, which can aid in validating optical techniques for clinical use. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License

Erfgesprekken over klimaatrobuuste beekdalen

De partners in Agrifood Capital denken na over het klimaatrobuust maken van beekdallandschappen in Noordoost Brabant. In dat kader zijn erfgesprekken gevoerd met landgebruikers in de benedenstroomse delen van de beekdalen van de Aa en van de Dommel, onder meer om inzicht te krijgen in wat meespeelt in hun overwegingen over gewenste en mogelijke aanpassing van het landgebruik. De landgebruikers hebben immers een centrale rol in een transitie naar klimaatrobuuste beekdalen, zowel qua inrichting als qua gebruik. Het ging om kwalitatief onderzoek. Er zijn groepsgesprekken en individuele gesprekken gevoerd met in totaal 21 grondeigenaren en grondgebruikers, waaronder 17 boeren. Voor diverse boeren is klimaatverandering iets ongrijpbaars. Ze zien nog weinig gevolgen van klimaatverandering en geloven niet dat het nodig is om aanpassingen te doen aan het landgebruik. Water moet kunnen worden vastgehouden en zo nodig snel weer worden afgevoerd. Diverse mogelijke maatregelen zijn besproken. De meesten zien meer in technische oplossingen zoals stuwen en drains dan in bijvoorbeeld het opnieuw laten meanderen van beken. Het verhogen van het organische stofgehalte in de bodem heeft brede steun en veel boeren werken daar al aan. Over het algemeen zijn respondenten best bereid om na te denken over aanpassingen op hun grond. Zelfs waterberging is bespreekbaar. Het gaat vooral om wederkerigheid. Het is belangrijk dat de landgebruikers erop vooruit kunnen gaan en dat er perspectief wordt geboden. Beschikbaarheid van grond is daarin van grote invloed. Daarnaast zal samenwerking gezocht moeten worden om te komen tot integrale gebiedsontwikkeling. Vanwege de grote verschillen in situatie en overtuigingen is het van belang om iedere grondgebruiker ook individueel te benaderen

A human-like bile acid pool induced by deletion of hepatic Cyp2c70 modulates effects of FXR activation in mice[S]

Bile acids (BAs) facilitate intestinal absorption of lipid-soluble nutrients and modulate various metabolic pathways through the farnesoid X receptor (FXR) and Takeda G-protein-coupled receptor 5. These receptors are targets for therapy in cholestatic and metabolic diseases. However, dissimilarities in BA metabolism between humans and mice complicate translation of preclinical data. Cytochrome P450 family 2 subfamily c polypeptide 70 (CYP2C70) was recently proposed to catalyze the formation of rodent-specific muricholic acids (MCAs). With CRISPR/Cas9-mediated somatic genome editing, we generated an acute hepatic Cyp2c70 knockout mouse model (Cyp2c70ako) to clarify the role of CYP2C70 in BA metabolism in vivo and evaluate whether its activity modulates effects of pharmacologic FXR activation on cholesterol homeostasis. In Cyp2c70ako mice, chenodeoxycholic acid (CDCA) increased at the expense of βMCA, resulting in a more hydrophobic human-like BA pool. Tracer studies demonstrated that, in vivo, CYP2C70 catalyzes the formation of βMCA primarily by sequential 6β-hydroxylation and C7-epimerization of CDCA, generating βMCA as an intermediate metabolite. Physiologically, the humanized BA composition in Cyp2c70ako mice blunted the stimulation of fecal cholesterol disposal in response to FXR activation compared with WT mice, predominantly due to reduced stimulation of transintestinal cholesterol excretion. Thus, deletion of hepatic Cyp2c70 in adult mice translates into a human-like BA pool composition and impacts the response to pharmacologic FXR activation. This Cyp2c70ako mouse model may be a useful tool for future studies of BA signaling and metabolism that informs human disease development and treatment

The impact of informal care-giving networks on adult children's care-giver burden

Previous research on the care-giver burden experienced by adult children has typically focused on the adult child and parent dyad. This study uses information on multiple informal care-givers and examines how characteristics of the informal care-giving network affect the adult child's care-giver burden. In 2007, 602 Dutch care-givers who were assisting their older parents reported on parental and personal characteristics, care activities, experienced burden and characteristics of other informal care-givers. A path model was applied to assess the relative impact of the informal care-giving network characteristics on the care-giver burden. An adult child experienced lower care-giver burden when the informal care-giving network size was larger, when more types of tasks were shared across the network, when care was shared for a longer period, and when the adult child had no disagreements with the other members of the network. Considering that the need for care of older parents is growing, being in an informal care-giving network will be of increasing benefit for adult children involved in long-term care. More care-givers will turn into managers of care, as they increasingly have to organise the sharing of care among informal helpers and cope with disagreements among the members of the network