Accelerating the analysis of optical quantum systems using the Koopman operator

The prediction of photon echoes is an important technique for gaining an understanding of optical quantum systems. However, this requires a large number of simulations with varying parameters and/or input pulses, which renders numerical studies expensive. This article investigates how we can use data-driven surrogate models based on the Koopman operator to accelerate this process. In order to be successful, we require a model that is accurate over a large number of time steps. To this end, we employ a bilinear Koopman model using extended dynamic mode decomposition and simulate the optical Bloch equations for an ensemble of inhomogeneously broadened two-level systems. Such systems are well suited to describe the excitation of excitonic resonances in semiconductor nanostructures, for example, ensembles of semiconductor quantum dots. We perform a detailed study on the required number of system simulations such that the resulting data-driven Koopman model is sufficiently accurate for a wide range of parameter settings. We analyze the L2 error and the relative error of the photon echo peak and investigate how the control positions relate to the stabilization. After proper training, the dynamics of the quantum ensemble can be predicted accurately and numerically very efficiently by our methods

Evaluating Ecological Sustainability For The Planning and Operations Of Storage Technologies

With an expected future increase of costs for carbon emissions the logistics industry is targeting to design sustainable warehouses to reduce their carbon footprints. To do so, it is required that every aspect of a warehouse from its general design to the transport processes and technologies must be assessed in terms of its carbon footprint. In this article the carbon footprint, which can be traced back to the storage technology employed within a storage area is analysed. The approach includes surface, material, and technology-related data to calculate the carbon footprint of a logistics concept. Firstly, different dimensions of storage technology carbon footprints are identified. A comprehen-sive model is provided to calculate the carbon footprint of alternative storage technologies in a warehouse. The model is applied in a case study with actual data from a warehouse planning project in the German production industry comparing three alternative storage technologies for a small part storage solution. The author's find highest carbon footprint in the application of an autonomous guided vehicle shelving system compared to automatic storage and retrieval system and manual storage solution using Kanban racks

Hepatic encephalopathy : novel insights into classification, pathophysiology and therapy

Hepatic encephalopathy (HE) is a frequent and serious complication of both chronic liver disease and acute liver failure. HE manifests as a wide spectrum of neuropsychiatric abnormalities, from subclinical changes (mild cognitive impairment) to marked disorientation, confusion and coma. The clinical and economic burden of HE is considerable, and it contributes greatly to impaired quality of life, morbidity and mortality. This review will critically discuss the latest classification of HE, as well as the pathogenesis and pathophysiological pathways underlying the neurological decline in patients with end-stage liver disease. In addition, management strategies, diagnostic approaches, currently available therapeutic options and novel treatment strategies are discussed

Progressive resistance training prevents loss of muscle mass and strength in bile duct‐ligated rats

BACKGROUND: Loss of muscle mass and strength is common in cirrhosis and increases the risk of hyperammonaemia and hepatic encephalopathy. Resistance training optimizes muscle mass and strength in several chronic diseases. However, the beneficial effects of resistance training in cirrhosis remain to be investigated. Bile duct-ligated (BDL) rats develop chronic liver disease, hyperammonaemia, reduced muscle mass and strength. Our aim was to test the effects of resistance training on muscle mass, function and ammonia metabolism in BDL-rats. METHODS: A group of BDL-rats underwent a progressive resistance training programme and a group of non-exercise BDL-rats served as controls. Resistance training comprised of ladder climbing with a progressive increase in carrying weights attached to the tail. Training was performed 5 days a week during 4 weeks. Muscle strength and body composition were assessed using grip strength and EchoMRI. Weight and circumference of the gastrocnemius muscle (normalized to bodyweight), plasma ammonia and glutamine synthetase protein expression and activity were assessed. RESULTS: BDL + exercise rats had significantly larger gastrocnemius circumference compared to non-exercise BDL-rats: ratio 0.082 vs 0.075 (P < 0.05). Gastrocnemius muscle weight was higher in exercisers than controls: 0.006 vs 0.005 (P < 0.05). A tendency towards a lower plasma ammonia in the exercise group compared to controls was observed (P = 0.10). There were no differences in lean body mass, GS protein expression and activity between the groups. CONCLUSION: Resistance training in rats with chronic liver disease beneficially effects muscle mass and strength. The effects were followed by non-significant reduction in blood ammonia; however, a tendency was observed

Accurate photon echo timing by optical freezing of exciton dephasing and rephasing in quantum dots

Semiconductor quantum dots are excellent candidates for ultrafast coherent manipulation of qubits by laser pulses on picosecond timescales or even faster. In inhomogeneous ensembles a macroscopic optical polarization decays rapidly due to dephasing, which, however, is reversible in photon echoes carrying complete information about the coherent ensemble dynamics. Control of the echo emission time is mandatory for applications. Here, we propose a concept to reach this goal. In a two-pulse photon echo sequence, we apply an additional resonant control pulse with multiple of 2π area. Depending on its arrival time, the control slows down dephasing or rephasing of the exciton ensemble during its action. We demonstrate for self-assembled (In,Ga)As quantum dots that the photon echo emission time can be retarded or advanced by up to 5 ps relative to its nominal appearance time without control. This versatile protocol may be used to obtain significantly longer temporal shifts for suitably tailored control pulses

Zuchtmaterialerstellung durch Erschließung und Selektion bisher nicht erfasster Anbau - und Verwertungsmerkmale in bisher nicht genutzten genetischen Ressourcen der Schmalblättrigen Lupine (Lupinus angustifolius L.)

An züchterisch bisher nicht genutzten, alkaloidreichen Genbankakzessionen der Schmalblättrigen Lupine des Vavilov Institutes der Pflanzenindustrie, St. Petersburg, wurden neben agronomischen Merkmalen die Merkmalskomplexe Rhizodeposition und Methioningehalt evaluiert. Für diese Merkmale wird im aktuellen, bitterstoffarmen Zuchtmaterial keine ausreichende, züchterisch nutzbare Variabilität mehr gefunden. Für den Merkmalskomplex Rhizodeposite konnten mittels Pyrolyse-Feldionisation Massenspektrometrie (Py-FIMS) lyophilisierter Rhizodeposite sowohl Genotypen mit erhöhter mikrobieller Abbaubarkeit zur Förderung der Rhizosphärenaktivität als auch mit erhöhten Konzentrationen antimikrobieller Komponenten identifiziert werden. Für den Merkmalskomplex Methioningehalt konnten die Schlüsselgene des Methioninstoffwechsels identifiziert und sequenziert werden. Für zwei der vier Schlüsselgene liegen allerdings so viele Kopien im Genom vor, dass sie züchterisch nur sehr schwer nutzbar sind. Es konnten mittels Transkript-Profiling keine hoch aktiven Allele der Schlüsselgene der Methioninbiosynthese identifiziert werden. Demgegenüber konnten in jungen Samen jedoch hochaktive Allele von Genen gefunden werden, die für methioninreiche Speicherproteine codieren. Für die folgenden agronomisch wichtigen Merkmale konnte im untersuchten Schmalblättrigen Lupinenmaterial eine erhebliche Variabilität gefunden werden, die weit über die in Blauen Süßlupinen noch gefundene Streuung hinaus geht: Kornertrag, Kornform, Grünmasseleistung, Rohproteingehalt, Boden-pH-Toleranz, sichere und synchrone Abreife der Hülsen, synchrone Laub- und Strohreife, Standfestigkeit, Platzfestigkeit, Resistenz gegenüber Anthraknose und Verticillium, Kornform. Die gefundene Variabilität gilt es jetzt züchterisch zu nutzen und die positiven Merkmalseigenschaften in neuen Sorten zu kombinieren

Hepatocyte-specific glucose-6-phosphatase deficiency disturbs platelet aggregation and decreases blood monocytes upon fasting-induced hypoglycemia

International audienceObjective: Glycogen storage disease type 1a (GSD Ia) is a rare inherited metabolic disorder caused by mutations in the glucose-6-phosphatase (G6PC1) gene. When untreated, GSD Ia leads to severe fasting-induced hypoglycemia. Although current intensive dietary management aims to prevent hypoglycemia, patients still experience hypoglycemic events. Poor glycemic control in GSD Ia is associated with hypertriglyceridemia, hepatocellular adenoma and carcinoma, and also with an increased bleeding tendency of unknown origin.Methods: To evaluate the effect of glycemic control on leukocyte levels and coagulation in GSD Ia, we employed hepatocyte-specific G6pc1 deficient (L-G6pc-/-) mice under fed or fasted conditions, to match good or poor glycemic control in GSD Ia, respectively.Results: We found that fasting-induced hypoglycemia in L-G6pc-/- mice decreased blood leukocytes, specifically pro-inflammatory Ly6Chi monocytes, compared to controls. Refeeding reversed this decrease. The decrease in Ly6Chi monocytes was accompanied by an increase in plasma corticosterone levels and was prevented by the glucocorticoid receptor antagonist mifepristone. Further, fasting-induced hypoglycemia in L-G6pc-/- mice prolonged bleeding time in the tail vein bleeding assay, with reversal by refeeding. This could not be explained by changes in coagulation factors V, VII, or VIII, or von Willebrand factor. While the prothrombin and activated partial thromboplastin time, as well as total platelet counts were not affected by fasting-induced hypoglycemia in L-G6pc-/- mice, ADP-induced platelet aggregation was disturbed.Conclusions: These studies reveal a relationship between fasting-induced hypoglycemia, decreased blood monocytes, and disturbed platelet aggregation in L-G6pc-/- mice. While disturbed platelet aggregation likely accounts for the bleeding phenotype in GSD Ia, elevated plasma corticosterone decreases levels of pro-inflammatory monocytes. These studies highlight the necessity of maintaining good glycemic control in GSD Ia

Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences

Non peer reviewe

Inhibition of ADAM17 impairs endothelial cell necroptosis and blocks metastasis

Metastasis is the major cause of death in cancer patients. Circulating tumor cells need to migrate through the endothelial layer of blood vessels to escape the hostile circulation and establish metastases at distant organ sites. Here, we identified the membrane-bound metalloprotease ADAM17 on endothelial cells as a key driver of metastasis. We show that TNFR1-dependent tumor cell–induced endothelial cell death, tumor cell extravasation, and subsequent metastatic seeding is dependent on the activity of endothelial ADAM17. Moreover, we reveal that ADAM17-mediated TNFR1 ectodomain shedding and subsequent processing by the γ-secretase complex is required for the induction of TNF-induced necroptosis. Consequently, genetic ablation of ADAM17 in endothelial cells as well as short-term pharmacological inhibition of ADAM17 prevents long-term metastases formation in the lung. Thus, our data identified ADAM17 as a novel essential regulator of necroptosis and as a new promising target for antimetastatic and advanced-stage cancer therapie

Scientific drilling projects in ancient lakes: integrating geological and biological histories

Sedimentary sequences in ancient or long-lived lakes can reach several thousands of meters in thickness and often provide an unrivalled perspective of the lake's regional climatic, environmental, and biological history. Over the last few years, deep drilling projects in ancient lakes became increasingly multi- and interdisciplinary, as, among others, seismological, sedimentological, biogeochemical, climatic, environmental, paleontological, and evolutionary information can be obtained from sediment cores. However, these multi- and interdisciplinary projects pose several challenges. The scientists involved typically approach problems from different scientific perspectives and backgrounds, and setting up the program requires clear communication and the alignment of interests. One of the most challenging tasks, besides the actual drilling operation, is to link diverse datasets with varying resolution, data quality, and age uncertainties to answer interdisciplinary questions synthetically and coherently. These problems are especially relevant when secondary data, i.e., datasets obtained independently of the drilling operation, are incorporated in analyses. Nonetheless, the inclusion of secondary information, such as isotopic data from fossils found in outcrops or genetic data from extant species, may help to achieve synthetic answers. Recent technological and methodological advances in paleolimnology are likely to increase the possibilities of integrating secondary information, e.g., through molecular dating of molecular phylogenies. Some of the new approaches have started to revolutionize scientific drilling in ancient lakes, but at the same time, they also add a new layer of complexity to the generation and analysis of sediment core data. The enhanced opportunities presented by new scientific approaches to study the paleolimnological history of these lakes, therefore, come at the expense of higher logistic, communication, and analytical efforts. Here we review types of data that can be obtained in ancient lake drilling projects and the analytical approaches that can be applied to empirically and statistically link diverse datasets for creating an integrative perspective on geological and biological data. In doing so, we highlight strengths and potential weaknesses of new methods and analyses, and provide recommendations for future interdisciplinary deep drilling projects