The VLQ Calorimeter of H1 at HERA: A Highly Compact Device for Measurements of Electrons and Photons under Very Small Scattering Angles

In 1998, the detector H1 at HERA has been equipped with a small backward spectrometer, the Very Low Q^2 (VLQ) spectrometer comprising a silicon tracker, a tungsten - scintillator sandwich calorimeter, and a Time-of-Flight system. The spectrometer was designed to measure electrons scattered under very low angles, equivalent to very low squared four - momentum transfers Q^2, and high energy photons with good energy and spatial resolution. The VLQ was in operation during the 1999 and 2000 run periods. This paper describes the design and construction of the VLQ calorimeter, a compact device with a fourfold projective energy read-out, and its performance during test runs and in the experiment.Comment: 32 pages, 25 figures, 2 tables (To be submitted to Nucl. Instrum. Meth. A

Sustainable Performance Optimization for Digital Housing

With natural resources depleting, sustainable solutions are becoming more and more a necessity. To deal with the depleting resources, the Dutch government aims to generate 14% of country’s energy consumption through natural resources by 2020. The Dutch built environment is estimated to be responsible for 38.1% of the total energy consumption. This means that investments and innovation within this area have high potential. However, there are some indications that these goals cannot be met. New houses often meet these requirements but, with a growth of 0.8% per year, these only make up for a small portion of all projects. As a result, a strong focus lays on improving and renovating the existing housing market towards a sustainable and low energy environment. For this transition, information on the current housing market, possible renovation options and insight on the investments costs are required. Within this PDEng-project the aim is to further develop WoonConnect, a digital tool that can help to speed up this transition for both renovation projects and new buildings

Memory effects on descent from nuclear fission barrier

Non-Markovian transport equations for nuclear large amplitude motion are derived from the collisional kinetic equation. The memory effects are caused by the Fermi surface distortions and depend on the relaxation time. It is shown that the nuclear collective motion and the nuclear fission are influenced strongly by the memory effects at the relaxation time $\tau \geq 5\cdot 10^{-23}{\rm s}$. In particular, the descent of the nucleus from the fission barrier is accompanied by characteristic shape oscillations. The eigenfrequency and the damping of the shape oscillations depend on the contribution of the memory integral in the equations of motion. The shape oscillations disappear at the short relaxation time regime at $\tau \to 0$, which corresponds to the usual Markovian motion in the presence of friction forces. We show that the elastic forces produced by the memory integral lead to a significant delay for the descent of the nucleus from the barrier. Numerical calculations for the nucleus $^{236}$U shows that due to the memory effect the saddle-to-scission time grows by a factor of about 3 with respect to the corresponding saddle-to-scission time obtained in liquid drop model calculations with friction forces.Comment: 22 pages, 8 figures, submitted to Phys. Rev.

Flexible Promoter Architecture Requirements for Coactivator Recruitment

Background: The spatial organization of transcription factor binding sites in regulatory DNA, and the composition of intersite sequences, influences the assembly of the multiprotein complexes that regulate RNA polymerase recruitment and thereby affects transcription. We have developed a genetic approach to investigate how reporter gene transcription is affected by varying the spacing between transcription factor binding sites. We characterized the components of promoter architecture that govern the yeast transcription factors Cbf1 and Met31/32, which bind independently, but collaboratively recruit the coactivator Met4. Results: A Cbf1 binding site was required upstream of a Met31/32 binding site for full reporter gene expression. Distance constraints on coactivator recruitment were more flexible than those for cooperatively binding transcription factors. Distances from 18 to 50 bp between binding sites support efficient recruitment of Met4, with only slight modulation by helical phasing. Intriguingly, we found that certain sequences located between the binding sites abolished gene expression. Conclusion: These results yield insight to the influence of both binding site architecture and local DNA flexibility on gene expression, and can be used to refine computational predictions of gene expression from promoter sequences. In addition, our approach can be applied to survey promoter architecture requirements for arbitrary combinations of transcription factor binding sites

Assessing availability and greenhouse gas emissions of lignocellulosic biomass feedstock supply – case study for a catchment in England

© 2019 Society of Chemical Industry and John Wiley & Sons, Ltd.Feedstocks from lignocellulosic biomass (LCB) include crop residues and dedicated per¬ennial biomass crops. The latter are often considered superior in terms of climate change mitigation potential. Uncertainty remains over their availability as feedstocks for biomass provision and the net greenhouse gas emissions (GHG) during crop production. Our objective was to assess the optimal land allocation to wheat and Miscanthus in a specific case study located in England, to increase bio¬mass availability, improve the carbon balance (and reduce the consequent GHG emissions), and mini¬mally constrain grain production losses from wheat. Using soil and climate variables for a catchment in east England, biomass yields and direct nitrogen emissions were simulated with validated process-based models. A ‘Field to up-stream factory gate’ life-cycle assessment was conducted to estimate indirect management-related GHG emissions. Results show that feedstock supply from wheat straw can be supplemented beneficially with LCB from Miscanthus grown on selected low-quality soils. In our study, 8% of the less productive arable land area was dedicated to Miscanthus, increasing total LCB provision by about 150%, with a 52% reduction in GHG emission per ton LCB delivered and only a minor effect on wheat grain production (−3%). In conclusion, even without considering the likely carbon sequestration in impoverished soils, agriculture should embrace the opportunities to provide the bioeconomy with LCB from dedicated, perennial crops.Peer reviewe

Demonstration of efficient beam-wave interaction for a MW-level 48 GHz gyroklystron amplifier

The development of high-frequency RF linear accelerators (linacs) requires the consideration of several technological challenges, such as electron bunch linearization. Presented in this paper is the design of the interaction circuit for a 48 GHz MW-level three-cavity gyroklystron amplifier, appropriate for application as a millimeter wave power source in a fourth harmonic linearizing system for an X-band linac. The output cavity is operated at the cylindrical TE0,2,1 mode, while the input and buncher cavities are operated at the TE0,1,1 mode. The interaction circuit has been designed using a combination of analytical calculations and particle-in-cell simulations. The optimized gyroklystron is shown, through simulation, to deliver an output power of up to 2.3 MW with a gain of 36 dB and an efficiency of 44% at 48 GHz, when driven by a 140 kV, 37 A electron beam. The   support   of   the   STFC   UK (Cockcroft Institute Core GrantR160525-1) is gratefully acknowledged. This  work  is  supported  by European Union (EU) Horizon 2020 Project  “CompactLight” 2017-2021. “CompactLight”  grant code: 777431-XLS. Published data March 2020, under Self-archiving / 'green' OA

Next generation tools for genomic data generation, distribution, and visualization

BACKGROUND: With the rapidly falling cost and availability of high throughput sequencing and microarray technologies, the bottleneck for effectively using genomic analysis in the laboratory and clinic is shifting to one of effectively managing, analyzing, and sharing genomic data. RESULTS: Here we present three open-source, platform independent, software tools for generating, analyzing, distributing, and visualizing genomic data. These include a next generation sequencing/microarray LIMS and analysis project center (GNomEx); an application for annotating and programmatically distributing genomic data using the community vetted DAS/2 data exchange protocol (GenoPub); and a standalone Java Swing application (GWrap) that makes cutting edge command line analysis tools available to those who prefer graphical user interfaces. Both GNomEx and GenoPub use the rich client Flex/Flash web browser interface to interact with Java classes and a relational database on a remote server. Both employ a public-private user-group security model enabling controlled distribution of patient and unpublished data alongside public resources. As such, they function as genomic data repositories that can be accessed manually or programmatically through DAS/2-enabled client applications such as the Integrated Genome Browser. CONCLUSIONS: These tools have gained wide use in our core facilities, research laboratories and clinics and are freely available for non-profit use. See http://sourceforge.net/projects/gnomex/, http://sourceforge.net/projects/genoviz/, and http://sourceforge.net/projects/useq

Statistical fluctuations for the fission process on its decent from saddle to scission

We reconsider the importance of statistical fluctuations for fission dynamics beyond the saddle in the light of recent evaluations of transport coefficients for average motion. The size of these fluctuations are estimated by means of the Kramers-Ingold solution for the inverted oscillator, which allows for an inclusion of quantum effects.Comment: 12 pages, Latex, 5 Postscript figures; submitted to PRC e-mail: [email protected] www home page: http://www.physik.tu-muenchen.de/tumphy/e/T36/hofmann.htm

The damping width of giant dipole resonances of cold and hot nuclei: a macroscopic model

A phenomenological macroscopic model of the Giant Dipole Resonance (GDR) damping width of cold- and hot-nuclei with ground-state spherical and near-spherical shapes is developed. The model is based on a generalized Fermi Liquid model which takes into account the nuclear surface dynamics. The temperature dependence of the GDR damping width is accounted for in terms of surface- and volume-components. Parameter-free expressions for the damping width and the effective deformation are obtained. The model is validated with GDR measurements of the following nuclides, $^{39,40}$K, $^{42}$Ca, $^{45}$Sc, $^{59,63}$Cu, $^{109-120}$Sn,$^{147}$Eu, $^{194}$Hg, and $^{208}$Pb, and is compared with the predictions of other models.Comment: 10 pages, 5 figure