26 research outputs found
Signatures of critical full counting statistics in a quantum-dot chain
We consider current shot noise and the full counting statistics in a chain of
quantum dots which exhibits a continuous non-equilibrium phase transition as a
function of the tunnel couplings of the chain with the electrodes. Using a
combination of analytical and numerical methods, we establish that the full
counting statistics is conventional away from the phase transition, but
becomes, in a well-defined sense, essentially non-Gaussian on the critical
line, where the current fluctuations are controlled by the dynamic critical
exponent . We find that signatures of the critical full counting statistics
persist in quantum-dot chains of finite length.Comment: 7 pages, 7 figure
SIAH2 antagonizes TYK2-STAT3 signaling in lung carcinoma cells
The Janus tyrosine kinases JAK1-3 and tyrosine kinase-2 (TYK2) are frequently hyperactivated in tumors. In lung cancers JAK1 and JAK2 induce oncogenic signaling through STAT3. A putative role of TYK2 in these tumors has not been reported. Here, we show a previously not recognized TYK2-STAT3 signaling node in lung cancer cells. We reveal that the E3 ubiquitin ligase seven-in-absentia-2 (SIAH2) accelerates the proteasomal degradation of TYK2. This mechanism consequently suppresses the activation of STAT3. In agreement with these data the analysis of primary non-small-cell lung cancer (NSCLC) samples from three patient cohorts revealed that compared to lung adenocarcinoma (ADC), lung squamous cell carcinoma (SCC) show significantly higher levels of SIAH2 and reduced STAT3 phosphorylation levels. Thus, SIAH2 is a novel molecular marker for SCC. We further demonstrate that an activation of the oncologically relevant transcription factor p53 in lung cancer cells induces SIAH2, depletes TYK2, and abrogates the tyrosine phosphorylation of STAT1 and STAT3. This mechanism appears to be different from the inhibition of phosphorylated JAKs through the suppressor of cytokine signaling (SOCS) proteins. Our study may help to identify molecular mechanisms affecting lung carcinogenesis and potential therapeutic targets
Good practices for take-back and disposal of unused pharmaceuticals in the Baltic Sea region. Clear Waters from Pharmaceuticals (CWPharma) Activity 4.1 Report
Appropriate collection and disposal of medicine-related waste has been identified as one of the main ways to decrease the emission of active pharmaceutical ingredients (APIs) into the environment. Improvement to the take-back and treatment of collected pharmaceutical waste may be considered low-hanging fruit when one is considering measures to reduce API emissions. However, comparable information that would enable estimating the potential impact of these efforts has not been available.
Directive 2004/27/EC, related to medicinal products for human use, mandates that EU member states implement appropriate collection schemes for unused or expired human-use medicinal products. However, it does not provide any guidelines on practical implementation of these schemes. Several studies have pointed out significant differences among Member States in this regard.
In March 2019, the European Commission published the European Union Strategic Approach to Pharmaceuticals in the Environment. The actions specified therein cover all stages of the pharmaceutical life cycle, from design and production to disposal and waste management. It emphasizes such elements as sharing good practices, co-operating at international level, and improving understanding of the risks.
This report is aimed at filling knowledge gaps and proposing good practices for take-back and disposal of unused human and veterinary medicines and other pharmaceutical waste. The report is targeted to e.g. ministries, environment and medicines agencies, supervisory authorities, municipalities, hospitals, NGOs, pharmacists, doctors, and veterinarians.
For the report, current national practices for take-back and disposal of unused medicines and other pharmaceutical waste in Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, and Sweden were evaluated. The pharmaceutical waste originating from households, hospitals and other health care institutions, the pharmaceutical industry, and veterinary use was considered.
The proportion of citizens who return unused pharmaceuticals via designated collection points varies greatly between Baltic Sea countries, from about 10% to 70%, with 16–80% disposing of them of as mixed household waste and 3–30% flushing them down the drain. The most commonly cited reason for improper disposal of medicines on households’ part is lack of information about their environmental impacts and how to get rid of them in an environmentally sound manner. Separate collection of unused household pharmaceuticals does not exist in Russia, and the collection mechanism functions poorly in Latvia, Lithuania and Poland. Information on the take-back schemes for unused human medicines is more readily available than is corresponding information on veterinary medicines.
We identified, all told, 21 good practices and recommendations for take-back and disposal of unused pharmaceuticals and other pharmaceutical waste and for promoting the rational use of pharmaceuticals in the Baltic Sea region. Nevertheless, implementing them at national level requires particular consideration due to differences in national legislation and other characteristics of the EU Baltic Sea countries and Russia. The good practices identified in this report answer the call issued in the EU strategic approach for an efficient risk-reduction strategy
Distribution Analysis of Hydrogenases in Surface Waters of Marine and Freshwater Environments
Background
Surface waters of aquatic environments have been shown to both evolve and consume hydrogen and the ocean is estimated to be the principal natural source. In some marine habitats, H2 evolution and uptake are clearly due to biological activity, while contributions of abiotic sources must be considered in others. Until now the only known biological process involved in H2 metabolism in marine environments is nitrogen fixation.
Principal Findings
We analyzed marine and freshwater environments for the presence and distribution of genes of all known hydrogenases, the enzymes involved in biological hydrogen turnover. The total genomes and the available marine metagenome datasets were searched for hydrogenase sequences. Furthermore, we isolated DNA from samples from the North Atlantic, Mediterranean Sea, North Sea, Baltic Sea, and two fresh water lakes and amplified and sequenced part of the gene encoding the bidirectional NAD(P)-linked hydrogenase. In 21% of all marine heterotrophic bacterial genomes from surface waters, one or several hydrogenase genes were found, with the membrane-bound H2 uptake hydrogenase being the most widespread. A clear bias of hydrogenases to environments with terrestrial influence was found. This is exemplified by the cyanobacterial bidirectional NAD(P)-linked hydrogenase that was found in freshwater and coastal areas but not in the open ocean.
Significance
This study shows that hydrogenases are surprisingly abundant in marine environments. Due to its ecological distribution the primary function of the bidirectional NAD(P)-linked hydrogenase seems to be fermentative hydrogen evolution. Moreover, our data suggests that marine surface waters could be an interesting source of oxygen-resistant uptake hydrogenases. The respective genes occur in coastal as well as open ocean habitats and we presume that they are used as additional energy scavenging devices in otherwise nutrient limited environments. The membrane-bound H2-evolving hydrogenases might be useful as marker for bacteria living inside of marine snow particles
On the importance of Task 1 and error performance measures in PRP dual-task studies
The psychological refractory period (PRP) paradigm is a dominant research tool in the literature on dual-task performance. In this paradigm a first and second component task (i.e., Task 1 and Task 2) are presented with variable stimulus onset asynchronies (SOAs) and priority to perform Task 1. The main indicator of dual-task impairment in PRP situations is an increasing Task 2-RT with decreasing SOAs. This impairment is typically explained with some task components being processed strictly sequentially in the context of the prominent central bottleneck theory. This assumption could implicitly suggest that processes of Task 1 are unaffected by Task 2 and bottleneck processing, i.e., decreasing SOAs do not increase reaction times (RTs) and error rates of the first task. The aim of the present review is to assess whether PRP dual-task studies included both RT and error data presentations and statistical analyses and whether studies including both data types (i.e., RTs and error rates) show data consistent with this assumption (i.e., decreasing SOAs and unaffected RTs and/or error rates in Task 1). This review demonstrates that, in contrast to RT presentations and analyses, error data is underrepresented in a substantial number of studies. Furthermore, a substantial number of studies with RT and error data showed a statistically significant impairment of Task 1 performance with decreasing SOA. Thus, these studies produced data that is not primarily consistent with the strong assumption that processes of Task 1 are unaffected by Task 2 and bottleneck processing in the context of PRP dual-task situations; this calls for a more careful report and analysis of Task 1 performance in PRP studies and for a more careful consideration of theories proposing additions to the bottleneck assumption, which are sufficiently general to explain Task 1 and Task 2 effects.Peer Reviewe