302 research outputs found
Dynamic adjustment of dispatching rule parameters in flow shops with sequence dependent setup times
Decentralized scheduling with dispatching rules is applied in many fields of production and logistics, especially in highly complex manufacturing systems. Since dispatching rules are restricted to their local information horizon, there is no rule that outperforms other rules across various objectives, scenarios and system conditions. In this paper, we present an approach to dynamically adjust the parameters of a dispatching rule depending on the current system conditions. The influence of different parameter settings of the chosen rule on system performance is estimated by a machine learning method, whose learning data is generated by preliminary simulation runs. Using a dynamic flow shop scenario with sequence dependent setup times, we demonstrate that our approach is capable of significantly reducing the mean tardiness of jobs
Abrasive Stripping Voltammetry and ESR Spectroscopy of Manganese in Carbonates
A combined approach using solid state electroanalysis (abrasive
stripping voltammetry) and ESR spectroscopy was made to characterize the different species of manganese which are present in
natural and synthetic calcium carbonates. Abrasive stripping voltammetry permits identifying Mn02 and MnC03, but the method
fails when it comes to detecting unambiguously MnC03 in the
presenee of Mn02. Neither can this method detect Mn2+ ions in
mixed crystals of Cal_xMIlxC03because of their low concentrations.
ESR spectroscopy can show that Mn2+ ions are present in
calcite on Ca2+ sites. Additionally, information about the state and
symmetry of Mn2+ site s and the local dynamics of the lattice can
be obtained. In aragonite, only extremely small amounts of individual
Mn2+ ions are present and most of the manganese is found in
the form of Mn02 agglomerates. Solid state electroanalysis and
ESR spectroscopy allow a rather complete qualitative specification
of manganese in calcium carbonates
Many-Body Localization Implies that Eigenvectors are Matrix-Product States
The phenomenon of many-body localization has received a lot of attention
recently, both for its implications in condensed-matter physics of allowing
systems to be an insulator even at nonzero temperature as well as in the
context of the foundations of quantum statistical mechanics, providing
examples of systems showing the absence of thermalization following out-of-
equilibrium dynamics. In this work, we establish a novel link between
dynamical propertiesâa vanishing group velocity and the absence of
transportâwith entanglement properties of individual eigenvectors. For systems
with a generic spectrum, we prove that strong dynamical localization implies
that all of its many-body eigenvectors have clustering correlations. The same
is true for parts of the spectrum, thus allowing for the existence of a
mobility edge above which transport is possible. In one dimension these
results directly imply an entanglement area law; hence, the eigenvectors can
be efficiently approximated by matrix-product states
Reliability of continuous cardiac output measurement during intra-abdominal hypertension relies on repeated calibrations: an experimental animal study
Hypothermia and postconditioning after cardiopulmonary resuscitation reduce cardiac dysfunction by modulating inflammation, apoptosis and remodeling
Background: Mild therapeutic hypothermia following cardiac arrest is neuroprotective, but its effect on myocardial dysfunction that is a critical issue following resuscitation is not clear. This study sought to examine whether hypothermia and the combination of hypothermia and pharmacological postconditioning are cardioprotective in a model of cardiopulmonary resuscitation following acute myocardial ischemia. Methodology/Principal Findings: Thirty pigs (28â34 kg) were subjected to cardiac arrest following left anterior descending coronary artery ischemia. After 7 minutes of ventricular fibrillation and 2 minutes of basic life support, advanced cardiac life support was started according to the current AHA guidelines. After successful return of spontaneous circulation (n = 21), coronary perfusion was reestablished after 60 minutes of occlusion, and animals were randomized to either normothermia at 38°C, hypothermia at 33°C or hypothermia at 33°C combined with sevoflurane (each group n = 7) for 24 hours. The effects on cardiac damage especially on inflammation, apoptosis, and remodeling were studied using cellular and molecular approaches. Five animals were sham operated. Animals treated with hypothermia had lower troponin T levels (p<0.01), reduced infarct size (34Âą7 versus 57Âą12%; p<0.05) and improved left ventricular function compared to normothermia (p<0.05). Hypothermia was associated with a reduction in: (i) immune cell infiltration, (ii) apoptosis, (iii) IL-1beta and IL-6 mRNA up-regulation, and (iv) IL-1beta protein expression (p<0.05). Moreover, decreased matrix metalloproteinase-9 activity was detected in the ischemic myocardium after treatment with mild hypothermia. Sevoflurane conferred additional protective effects although statistic significance was not reached. Conclusions/Significance: Hypothermia reduced myocardial damage and dysfunction after cardiopulmonary resuscitation possible via a reduced rate of apoptosis and pro-inflammatory cytokine expression
CAP-T cell expression system: a novel rapid and versatile human cell expression system for fast and high yield transient protein expression
Evidence for a major role of antisense RNAs in cyanobacterial gene regulation
Information on the numbers and functions of naturally occurring antisense RNAs (asRNAs) in eubacteria has thus far remained incomplete. Here, we screened the model cyanobacterium Synechocystis sp. PCC 6803 for asRNAs using four different methods. In the final data set, the number of known noncoding RNAs rose from 6 earlier identified to 60 and of asRNAs from 1 to 73 (28 were verified using at least three methods). Among these, there are many asRNAs to housekeeping, regulatory or metabolic genes, as well as to genes encoding electron transport proteins. Transferring cultures to high light, carbon-limited conditions or darkness influenced the expression levels of several asRNAs, suggesting their functional relevance. Examples include the asRNA to rpl1, which accumulates in a light-dependent manner and may be required for processing the L11 r-operon and the SyR7 noncoding RNA, which is antisense to the murF 5ⲠUTR, possibly modulating murein biosynthesis. Extrapolated to the whole genome, âź10% of all genes in Synechocystis are influenced by asRNAs. Thus, chromosomally encoded asRNAs may have an important function in eubacterial regulatory networks
Bunker Cave stalagmites: an archive for central European Holocene climate variability
Holocene climate was characterised by variability on multi-centennial to multi-decadal time scales. In central Europe, these fluctuations were most pronounced during winter. Here we present a record of past winter climate variability for the last 10.8 ka based on four speleothems from Bunker Cave, western Germany. Due to its central European location, the cave site is particularly well suited to record changes in precipitation and temperature in response to changes in the North Atlantic realm. We present high-resolution records of δ18O, δ13C values and Mg/Ca ratios. Changes in the Mg/Ca ratio are attributed to past meteoric precipitation variability. The stable C isotope composition of the speleothems most likely reflects changes in vegetation and precipitation, and variations in the δ18O signal are interpreted as variations in meteoric precipitation and temperature. We found cold and dry periods between 8 and 7 ka, 6.5 and 5.5 ka, 4 and 3 ka as well as between 0.7 and 0.2 ka. The proxy signals in the Bunker Cave stalagmites compare well with other isotope records and, thus, seem representative for central European Holocene climate variability. The prominent 8.2 ka event and the Little Ice Age cold events are both recorded in the Bunker Cave record. However, these events show a contrasting relationship between climate and δ18O, which is explained by different causes underlying the two climate anomalies. Whereas the Little Ice Age is attributed to a pronounced negative phase of the North Atlantic Oscillation, the 8.2 ka event was triggered by cooler conditions in the North Atlantic due to a slowdown of the thermohaline circulation
Myth-busting the provider-user relationship for digital sequence information.
[EN] BACKGROUND: The United Nations Convention on Biological Diversity (CBD) formally recognized the sovereign rights of nations over their biological diversity. Implicit within the treaty is the idea that mega-biodiverse countries will provide genetic resources and grant access to them and scientists in high-income countries will use these resources and share back benefits. However, little research has been conducted on how this framework is reflected in real-life scientific practice.
RESULT: Currently, parties to the CBD are debating whether digital sequence information (DSI) should be regulated under a new benefit-sharing framework. At this critical time point in the upcoming international negotiations, we test the fundamental hypothesis of provision and use of DSI by looking at the global patterns of access and use in scientific publications.
CONCLUSION: Our data reject the provider-user relationship and suggest a far more complex information flow for DSI. Therefore, any new policy decisions on DSI should be aware of the high level of use of DSI across low- and middle-income countries and seek to preserve open access to this crucial common good.This publication was made possible by the research project WiLDSI (Wissenschaftliche LÜsungsansätze fßr Digitale Sequenzinformation) funded by the German Federal Ministry of Education and Research (BMBF) under funding code 031B0862
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