1,789 research outputs found
Nährstoffverfügbarkeit und Nährstoffnutzung von klee- und kräuterreichen Aufwüchsen ökologisch bewirtschafteten Grünlandes entlang der Produktionskette Erzeugung - Konservierung - Verdauung
Ziel des Vorhabens war es, kräuterreiche Grünlandaufwüchse, die im Ökologischen Landbau eine große Bedeutung haben, im Hinblick auf die Futterqualität und die Tierernährung zu bewerten. Für Frühjahrs- und Sommeraufwüchse wurden die Futterqualitäts- und Konservierungseigenschaften eines ungedüngten kräuterreichen Grünlandes und eines ungedüngten Weißklee-Weidelgrasbestandes mit dem eines mit mineralischem Stickstoff gedüngten reinen Weidelgrasbestandes (konventionelle Vergleichsvariante) verglichen. Beim kräuterreichen Grünland bestand der Kräuteranteil aus den feinblättrigen Arten Löwenzahn und Spitzwegerich. Futter wurde im Labormaßstab einsiliert und die Gärfähigkeit sowie die Silagequalität ermittelt. Die Verdauungsphysiologie wurde anhand der Pansensimulationstechnik ‚Rusitec’ studiert. Die kräuterreichen Aufwüchse wiesen eine im Vergleich zum reinen Grasbestand gute Siliereignung und Silagequalität auf mit geringen Ammoniakgehalten und niedrigem Proteinabbau. Kräuterreiches Futter enthielt weniger Rohprotein und Gerüstsubstanzen. Bei der Enzymlöslichkeit der organischen Substanz (ELOS) und der energetischen Bewertung (HFT) traten keine signifikanten Unterschiede zwischen den Varianten auf. Dagegen erwiesen sich die Silagen aus kräuterreichen Aufwüchsen in der Pansensimulation als geringer abbaubar, die mikrobielle Zell- bzw. Proteinsynthese war im Vergleich zur Gras-Klee- und insbesondere gegenüber der Grasvariante vermindert. Die Ergebnisse weisen auf ein hohes, N-effizientes Verwertungspotential kräuterreicher Grünlandaufwüchse in der Wiederkäuerfütterung hin. Es bleibt zu klären, ob die nicht mikrobiell im Pansen abbaubaren Futterbestandteile postruminal zur Energie- und Nährstoffversorgung des Wiederkäuers beizutragen vermögen
Tunable spin-selective loading of a silicon spin qubit
The remarkable properties of silicon have made it the central material for
the fabrication of current microelectronic devices. Silicon's fundamental
properties also make it an attractive option for the development of devices for
spintronics and quantum information processing. The ability to manipulate and
measure spins of single electrons is crucial for these applications. Here we
report the manipulation and measurement of a single spin in a quantum dot
fabricated in a silicon/silicon-germanium heterostructure. We demonstrate that
the rate of loading of electrons into the device can be tuned over an order of
magnitude using a gate voltage, that the spin state of the loaded electron
depends systematically on the loading voltage level, and that this tunability
arises because electron spins can be loaded through excited orbital states of
the quantum dot. The longitudinal spin relaxation time T1 is measured using
single-shot pulsed techniques and found to be ~3 seconds at a field of 1.85
Tesla. The demonstration of single spin measurement as well as a long spin
relaxation time and tunability of the loading are all favorable properties for
spintronics and quantum information processing applications.Comment: 4 pages, 3 figures, Supplemental Informatio
Recurrent pregnancy loss is associated with a pro-senescent decidual response during the peri-implantation window
During the implantation window, the endometrium becomes poised to transition to a pregnant state, a process driven by differentiation of stromal cells into decidual cells (DC). Perturbations in this process, termed decidualization, leads to breakdown of the feto-maternal interface and miscarriage, but the underlying mechanisms are poorly understood. Here, we reconstructed the decidual pathway at single-cell level in vitro and demonstrate that stromal cells first mount an acute stress response before emerging as DC or senescent DC (snDC). In the absence of immune cell-mediated clearance of snDC, secondary senescence transforms DC into progesterone-resistant cells that abundantly express extracellular matrix remodelling factors. Additional single-cell analysis of midluteal endometrium identified DIO2 and SCARA5 as marker genes of a diverging decidual response in vivo. Finally, we report a conspicuous link between a pro-senescent decidual response in peri-implantation endometrium and recurrent pregnancy loss, suggesting that pre-pregnancy screening and intervention may reduce the burden of miscarriage
Undrained shear strength of soft clay mixed with different percentages of lime and silica fume
Soil stabilisation, as a cost-effective and environmentally friendly method, is used in the building of systems like roads, dams, canals and river levels. Chemical stabilisation of soil is carried out by adding binder or by-products like lime and silica fume to the soil thereby modifying the geotechnical performance of the soil. Various researchers have carried out research on the properties of soil, such as its compaction, compressibility, hydraulic conductivity, and strength characteristics. The focus of the study was the determination of the physical properties of the soft clay used and the strength of soft clay (kaolin) mixed with 6 % of silica fume and various percentages (3 %, 5 %, 7 % and 9 %) of lime. Unconfined compression test was carried out on the soft clay and the mixtures of soft clay-lime-silica fume to investigate the effect of lime stabilisation with silica fume additives on the unconfined compressive strength of the mixtures. Based on the results obtained, all soil samples were indicated as soils with medium plasticity. From 0 % to 9 % of lime with 6 % of silica fume, the decreased in the maximum dry density was by 5.92 % and the increased in the optimum moisture content was by 23.5 %. Decreased in the coefficient of permeability of the mixtures occurred when compared to the coefficient of permeability of the soft clay itself. The improvement in shear strength of soft clay mixed with 6 % silica fume and 5 % lime was 29.83 % compared to the shear strength of the soft clay sample. The optimal percentage of lime-silica fume combination was attained at 5.0 % of lime and 6.0 % of silica fume in order to improve the shear strength of soft clay. It can be concluded that lime-silica fume additives improved the unconfined compressive strength of the soft clay
Exploring the optimal allostatic load scoring method in women of reproductive age
AimsThe aim of this study was to determine the optimal allostatic load scoring method.DesignThis is a secondary analysis of data on women of reproductive age from the 2001-2006 National Health and Nutrition Examination Survey.MethodsWe created allostatic load summary scores using five scoring methods including the count-based, Z-Score, logistic regression, factor analysis and grade of membership methods. Then, we examined the predictive performance of each allostatic load summary measure in relation to three outcomes: general health status, diabetes and hypertension.ResultsWe found that the allostatic load summary measure by the logistic regression method had the highest predictive validity with respect to the three outcomes. The logistic regression method performed significantly better than the count-based and grade of membership methods for predicting diabetes as well as performed significantly better for predicting hypertension than all of the other methods. But the five scoring methods performed similarly for predicting poor health status.ConclusionWe recommended the logistic regression method when the outcome information is available, otherwise the frequently used simpler count-based method may be a good alternative.ImpactThe study compared different scoring methods and made recommendations for the optimal scoring approach. We found that allostatic load summary measure by the logistic regression method had the strongest predictive validity with respect to general health status, diabetes and hypertension. The study may provide empirical evidence for future research to use the recommended scoring approach to score allostatic load. The allostatic load index may serve as an -early warning- indicator for health risk.ç ®ç è¿ é¡¹ç 究ç ç ®ç å ¨äº ,ç¡®å® æ ä½³é åº è´ è ·è¯ å æ ¹æ³ ã è®¾è®¡è¿ æ ¯å¯¹2001å¹´è ³2006æ é ´å ¨å ½å ¥åº·å è ¥å »æ£ æ ¥è° æ ¥ä¸è ²é¾ å¦ å¥³æ °æ ®ç äº æ¬¡å æ ã æ ¹æ³ æ ä»¬ä½¿ç ¨äº äº ç§ è¯ å æ ¹æ³ (å æ ¬å ºäº è®¡æ °æ³ ã Z计å æ³ ã é »è¾ å å½ æ³ ã å å å æ æ³ å é ¶å± åº¦æ ¹æ³ )æ ¥å å»ºäº é åº è´ è ·æ± æ »å æ °ã ç ¶å ,æ ä»¬æ£ æ ¥äº ä¸ ä¸ ä¸ªç» æ ç ¸å ³ç å ç§ é åº è´ è ·æ± æ »æ °å ¼ç é¢ æµ æ §è ½:æ ´ä½ å ¥åº·ç ¶æ ã ç³ å°¿ç å é« è¡ å ã ç» æ æ 们å ç °,é »è¾ å å½ æ³ ç é åº è´ è ·æ± æ »å æ °å¯¹è¿ ä¸ ä¸ªç» æ å ·æ æ é« ç é¢ æµ æ 度ã é »è¾ å å½ æ³ å ¨é¢ æµ ç³ å°¿ç æ ¹é ¢ç è¡¨ç °æ æ ¾ä¼ äº å ºäº è®¡æ °æ³ å é ¶å± åº¦æ ¹æ³ ,å ¨é¢ æµ é« è¡ å æ ¹é ¢ç è¡¨ç °ä¹ æ æ ¾ä¼ äº æ æ å ¶ä» æ ¹æ³ ã ä½ è¿ äº ç§ è¯ å æ ¹æ³ å ¨é¢ æµ ä¸ è ¯å ¥åº·ç ¶æ æ ¹é ¢ç è¡¨ç °ç ¸ä¼¼ã ç» è®ºå½ ç» æ èµ æ å ¯ç ¨æ ¶,æ ä»¬æ ¨è é »è¾ å å½ æ³ ,å ¨å ¶ä» æ ¹é ¢,å¸¸ç ¨ä¸ æ ´ç® å ç å ºäº è®¡æ °æ³ å ¯è ½ä¹ æ ¯ä¸ ä¸ªä¸ é ç é æ ©ã å½±å 该ç ç©¶æ¯ è¾ äº ä¸ å ç è¯ å æ ¹æ³ ,并æ å ºäº æ ä½³è¯ å æ ¹æ³ ç 建议ã æ 们å ç °ç ¨é »è¾ å å½ æ³ è¿ è¡ ç é åº è´ è ·æ± æ »å æ °å¯¹æ ´ä½ å ¥åº·ç ¶æ ã ç³ å°¿ç å é« è¡ å å ·æ æ 强ç é¢ æµ æ æ æ §ã 该ç ç©¶å ¯ä»¥ä¸ºä» å ä½¿ç ¨æ ¨è ç è¯ å æ ¹æ³ å¯¹æ æ é åº è´ è ·è¯ å æ ä¾ å® éª æ §è¯ æ ®ã é åº è´ è ·æ æ °å ¯ä»¥ä½ ä¸ºå ¥åº·é£ é ©ç -é¢ è¦-æ æ ãPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151983/1/jan14014_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151983/2/jan14014.pd
Photonic Band Gaps in 3D Network Structures with Short-range Order
We present a systematic study of photonic band gaps (PBGs) in
three-dimensional (3D) photonic amorphous structures (PAS) with short-range
order. From calculations of the density of optical states (DOS) for PAS with
different topologies, we find that tetrahedrally connected dielectric networks
produce the largest isotropic PBGs. Local uniformity and tetrahedral order are
essential to the formation of PBGs in PAS, in addition to short-range geometric
order. This work demonstrates that it is possible to create broad, isotropic
PBGs for vector light fields in 3D PAS without long-range order.Comment: 6 pages, 8 figure
A content-linking-context model for “notice-and-takedown” procedures
The US Digital Millennium Copyright Act (DMCA) of 1998 adopted a notice-and-take-down procedure to help tackle alleged online infringements through online service providers’ actions. The European Directive 2000/31/EC (e-Commerce Directive) introduced similar liability exemptions, but did not specify any take-down procedure. Many intermediary (host, and online search engine) service providers even in Europe have followed this notice-and-take-down procedure to enable copyright owners to issue notices to take down allegedly infringing Web resources. However, the accuracy of take-down is not known, and notice receivers do not reveal clear information about how they check the legitimacy of these requests, about whether and how they check the lawfulness of allegedly infringing content, or what criteria they use for these actions. In this paper, we use Google’s Transparency Report as the benchmark to investigate the information content of take-down notices and the accuracy of the resulting take-downs of allegedly infringing Web resources. The analysis of copyright infringement is limited to the five scenarios most frequently encountered in our study of Web resources. Based on our investigation, we propose a Content-Linking-Context (CLC) model of the criteria to be considered by intermediary service providers to achieve more accurate take-down
Response of low-strength phenol-acclimated activated sludge to shock loading of high phenol concentrations
(ii) investigate the degradation pathways and (iii) model the growth and biodegradation kinetics, all under the condition of increasingly higher phenol concentrations (step-up shock loading). With the use of activated sludge acclimated to phenol concentration of 140 mg∙ℓ−1 (low-strength phenol-acclimated activated sludge), complete degradation of phenol with a COD removal efficiency of more than 95% was achieved up to 1 050 mg∙ℓ−1 of initial phenol concentration. At low initial phenol concentrations, the experimental results were indicative of the meta-cleavage pathway for phenol degradation. When the initial phenol concentration was above 630 mg∙ℓ−1, the degradation results were indicative of both meta- and ortho-cleavage pathways. The values of the Haldane kinetic parameters indicated a low degree of inhibition exerted by the presence of increasing phenol concentration. This was substantiated by the observation that the rate constant of phenol removal decreased by only 33% even though the initial phenol concentration was increased by 15 times from 70 to 1 050 mg∙ℓ−1.Thus, the activated sludge acclimated to only 140 mg∙ℓ−1 of phenol could successfully treat up to 1 050 mg∙ℓ−1 of phenol without experiencing complete inhibition during the degradation process.Keywords: Phenol removal, low-strength phenol-acclimated activated sludge, degradation pathway, Haldane kinetic paramete
Quantum control and process tomography of a semiconductor quantum dot hybrid qubit
The similarities between gated quantum dots and the transistors in modern
microelectronics - in fabrication methods, physical structure, and voltage
scales for manipulation - have led to great interest in the development of
quantum bits (qubits) in semiconductor quantum dots. While quantum dot spin
qubits have demonstrated long coherence times, their manipulation is often
slower than desired for important future applications, such as factoring.
Further, scalability and manufacturability are enhanced when qubits are as
simple as possible. Previous work has increased the speed of spin qubit
rotations by making use of integrated micromagnets, dynamic pumping of nuclear
spins, or the addition of a third quantum dot. Here we demonstrate a new qubit
that offers both simplicity - it requires no special preparation and lives in a
double quantum dot with no added complexity - and is very fast: we demonstrate
full control on the Bloch sphere with -rotation times less than 100 ps in
two orthogonal directions. We report full process tomography, extracting high
fidelities equal to or greater than 85% for X-rotations and 94% for
Z-rotations. We discuss a path forward to fidelities better than the threshold
for quantum error correction.Comment: 6 pages, excluding Appendi
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