| 1. |
- Erni, W., et al.
(författare)
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Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker
- 2013
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Ingår i: European Physical Journal A. Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 49:2
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Tidskriftsartikel (refereegranskat)abstract
- This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described.
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| 2. |
- Golub, Malgorzata, et al.
(författare)
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Diel, seasonal, and inter-annual variation in carbon dioxide effluxes from lakes and reservoirs
- 2023
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Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 18:3
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Tidskriftsartikel (refereegranskat)abstract
- Accounting for temporal changes in carbon dioxide (CO2) effluxes from freshwaters remains a challenge for global and regional carbon budgets. Here, we synthesize 171 site-months of flux measurements of CO2 based on the eddy covariance method from 13 lakes and reservoirs in the Northern Hemisphere, and quantify dynamics at multiple temporal scales. We found pronounced sub-annual variability in CO2 flux at all sites. By accounting for diel variation, only 11% of site-months were net daily sinks of CO2. Annual CO2 emissions had an average of 25% (range 3%-58%) interannual variation. Similar to studies on streams, nighttime emissions regularly exceeded daytime emissions. Biophysical regulations of CO2 flux variability were delineated through mutual information analysis. Sample analysis of CO2 fluxes indicate the importance of continuous measurements. Better characterization of short- and long-term variability is necessary to understand and improve detection of temporal changes of CO2 fluxes in response to natural and anthropogenic drivers. Our results indicate that existing global lake carbon budgets relying primarily on daytime measurements yield underestimates of net emissions.
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| 3. |
- Liljeruhm, Josefine, et al.
(författare)
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Engineering a palette of eukaryotic chromoproteins for bacterial synthetic biology
- 2018
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Ingår i: Journal of Biological Engineering. - : BIOMED CENTRAL LTD. - 1754-1611. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Background: Coral reefs are colored by eukaryotic chromoproteins (CPs) that are homologous to green fluorescent protein. CPs differ from fluorescent proteins (FPs) by intensely absorbing visible light to give strong colors in ambient light. This endows CPs with certain advantages over FPs, such as instrument-free detection uncomplicated by ultra-violet light damage or background fluorescence, efficient Forster resonance energy transfer (FRET) quenching, and photoacoustic imaging. Thus, CPs have found utility as genetic markers and in teaching, and are attractive for potential cell biosensor applications in the field. Most near-term applications of CPs require expression in a different domain of life: bacteria. However, it is unclear which of the eukaryotic CP genes might be suitable and how best to assay them.Results: Here, taking advantage of codon optimization programs in 12 cases, we engineered 14 CP sequences (meffRed, eforRed, asPink, spisPink, scOrange, fwYellow, amilGFP, amajLime, cjBlue, mefiBlue, aeBlue, amilCP, tsPurple and gfasPurple) into a palette of Escherichia coil BioBrick plasmids. BioBricks comply with synthetic biology's most widely used, simplified, cloning standard. Differences in color intensities, maturation times and fitness costs of expression were compared under the same conditions, and visible readout of gene expression was quantitated. A surprisingly large variation in cellular fitness costs was found, resulting in loss of color in some overnight liquid cultures of certain high-copy-plasmid-borne CPs, and cautioning the use of multiple CPs as markers in competition assays. We solved these two problems by integrating pairs of these genes into the chromosome and by engineering versions of the same CP with very different colors.Conclusion: Availability of 14 engineered CP genes compared in E coil, together with chromosomal mutants suitable for competition assays, should simplify and expand CP study and applications. There was no single plasmid-borne CP that combined all of the most desirable features of intense color, fast maturation and low fitness cost, so this study should help direct future engineering efforts.
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| 4. |
- Lundin, Erik, et al.
(författare)
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Scintigraphic assessment of slow transit constipation with special reference to right- or left-sided colonic delay
- 2004
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Ingår i: Colorectal Disease. - : Wiley. - 1462-8910 .- 1463-1318. ; 6:6, s. 499-505
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Subtotal colectomy and ileorectal anastomosis for slow transit constipation has several side-effects. The motor abnormality in some patients may be segmental which could motivate a limited resection of the colon. Therefore a diagnostic tool to identify a segmental colonic motor dysfunction is needed. The aim of this study was to evaluate a scintigraphic method to assess colonic transit with special reference to right- or left-sided delay. METHODS: Twenty-three constipated patients (19 women, mean age 50 years) with slow colonic transit on radio-opaque marker studies and 13 healthy individuals (11 women, mean age 46 years) were studied. All subjects were examined with oral (111)Indium-DTPA scintigraphy. The scintigraphic results for patients and controls were presented as geometric centre of radioactivity and percent activity over time in the right, the left and the recto-sigmoid colon. The inter-observer variation in the interpretation of the scans was also evaluated. RESULTS: There was no difference in transit time between the groups of patients and controls in the right colon whereas the patients had a significant delay in the left colon (P < 0.05). Two patients had a marked delay in the right colon followed by relatively rapid transit in the left colon. The inter-observer correlation was good comparing the right, the left and the recto-sigmoid colon (r = 0.58-0.98, P < 0.01-0.001). CONCLUSION: The results indicate that colonic scintigraphy with oral (111)Indium-DTPA may help to select patients for a left or, in a few cases, a right hemicolectomy for slow transit constipation.
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| 5. |
- Marcks von Wurtemberg, Klas, et al.
(författare)
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The response of lead-tungstate scintillators (PWO) to photons with energies in the range 13 MeV-64 MeV
- 2012
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576 .- 0167-5087. ; 679, s. 36-43
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Tidskriftsartikel (refereegranskat)abstract
- The response of a matrix of 25 lead tungstate (PWO) scintillator detectors, operated at -25 degrees C, to photons in the range 13 MeV-64 MeV has been measured at the tagged-photon facility at MAX-lab, Lund. The tapered PWO crystals, each with a length of 200 mm and a cross-section of 24.4 x 24.4 mm(2) in the front end, read out by 19 mm photomultiplier tubes, were arranged in a 5 x 5 matrix. The response was measured for photons directed towards the centre of the central crystal as well as for photons directed towards the corner of the central crystal, where four crystals meet. The obtained energy resolution surpasses what has been published so far and is close to the limit given by Poisson statistics and escaped energy. For photons directed towards the centre(corner) of the central crystal the relative energy resolution, defined as (FWHM/2.35)/E-gamma, decreases from 7.3%(11.0%) at E-gamma = 13 MeV to 3.3%(3.6%) at E-gamma = 64 MeV. The reconstructed point of impact of a photon in this energy range is determined with an uncertainty (one standard deviation) of 7.3 +/- 0.1 mm.
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| 6. |
- Bergman, Hilde-Marléne, et al.
(författare)
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Quantitative mass spectrometry imaging of small-molecule neurotransmitters in rat brain tissue sections using nanospray desorption electrospray ionization
- 2016
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Ingår i: The Analyst. - : Royal Society of Chemistry (RSC). - 0003-2654 .- 1364-5528. ; 141:12, s. 3686-3695
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Tidskriftsartikel (refereegranskat)abstract
- Small molecule neurotransmitters are essential for the function of the nervous system, and neurotransmitter imbalances are often connected to neurological disorders. The ability to quantify such imbalances is important to provide insights into the biochemical mechanisms underlying the disorder. This proof-of-principle study presents online quantification of small molecule neurotransmitters, specifically acetylcholine, γ-aminobutyric acid (GABA) and glutamate, in rat brain tissue sections using nanospray desorption electrospray ionization (nano-DESI) mass spectrometry imaging. By incorporating deuterated internal standards in the nano-DESI solvent we show identification, accurate mapping, and quantification of these small neurotransmitters in rat brain tissue without introducing any additional sample preparation steps. We find that GABA is about twice as abundant in the medial septum-diagonal band complex (MSDB) as in the cortex, while glutamate is about twice as abundant in the cortex as compared to the MSDB. The study shows that nano-DESI is well suited for imaging of small molecule neurotransmitters in health and disease.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Halldin, Sven, et al.
(författare)
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NOPEX - a northern hemisphere climate processes land surface experiment
- 1998
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Ingår i: Journal of Hydrology. - 0022-1694 .- 1879-2707. ; 212-213, s. 172-187
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Tidskriftsartikel (refereegranskat)abstract
- The interface between land surfaces and the atmosphere is a key area in climate research, where lack of basic knowledge prevents us from reducing the considerable uncertainties about predicted changes. Boreal forests play an important, but not well known, role in the global hydrological and biogeochemical cycles. NOPEX (a NOrthern hemisphere climate Processes land surface EXperiment) is devoted to the study of land surface-atmosphere interaction in a northern European forest-dominated landscape. The main NOPEX region represents the southern edge of the boreal zone. It consists of a highly heterogeneous landscape, with forests, mires, agricultural land and lakes. A second study site, in northern Finland, representing the northern edge of the boreal zone, will be introduced into NOPEX in connection with its coming winter-time field activities. Field activities, dominating the initial phase of NOPEX, are conceived to strike a balance between the need to cover multi-annual observations and the resources required to carry out measurements covering all relevant spatial scales. The long-term data collection activities, the Continuous Climate Monitoring (CCM), form the backbone of the field programme. A suite of Concentrated Field Efforts (CFEs) covering periods of summer, spring and winter brings together scientists from more then 20 countries during month-long campaigns. CFEs have been carried out in May-June 1994 and April-July 1995. A third, winter-time CFE is planned for 1998-99. The System for Information in NOPEX (SINOP) is the database which forms a backbone for modelling and analysis work, dominating the second stage of NOPEX. A series of PhD courses are run in parallell to the research activities. Analysis and modelling are done in four interacting areas, including local-scale processes, meso-scale surface-atmosphere coupling and remote sensing techniques. The fourth area, regionalization methods, aims at bringing the previous three together in order to provide improved parameterization schemes for exchange of energy, momentum, water and CO2 between land and atmosphere in hydrological and meteorological models from the meso to the global scale.
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