Mesoscopic Transport Through Ballistic Cavities: A Random S-Matrix Theory Approach

We deduce the effects of quantum interference on the conductance of chaotic cavities by using a statistical ansatz for the S matrix. Assuming that the circular ensembles describe the S matrix of a chaotic cavity, we find that the conductance fluctuation and weak-localization magnitudes are universal: they are independent of the size and shape of the cavity if the number of incoming modes, N, is large. The limit of small N is more relevant experimentally; here we calculate the full distribution of the conductance and find striking differences as N changes or a magnetic field is applied.Comment: 4 pages revtex 3.0 (2-column) plus 2 postscript figures (appended), hub.pam.94.

BASEWECS - Influence of the Baltic Sea and its annual ice coverage on the water and energy budget of the Baltic Sea

BASEWECS is a contribution to the German Climate Research Program DEKLIM. The project started in May 2001 and lasted until December 2004. BASEWECS aimed at the investigation of the influence of the Baltic Sea and its annual ice coverage on the water and energy budget of the BALTEX are

Zonal pressure gradient along the equatorial Atlantic

For three consecutive periods during the summer of 1974, ships of many nations made observations along the Atlantic equator as part of the GATE program [GARP (Global Atmospheric Research Program) Atlantic Tropical Experiment]. Combining these observations, it is found that the zonal pressure gradient over the central Atlantic at the surface and at 50 dbar, relative to 500 dbar, increased from 3.2 to 7.3 and 2.2 to 5.3 × 10-5 dynes/g respectively between June/July and August and then held close to the high values in September...

Automated Non-Sterile Pharmacy Compounding: A Multi-Site Study in European Hospital and Community Pharmacies with Pediatric Immediate Release Propranolol Hydrochloride Tablets.

Pharmacy compounding, the art and science of preparing customized medications to meet individual patient needs, is on the verge of transformation. Traditional methods of compounding often involve manual and time-consuming processes, presenting challenges in terms of consistency, dosage accuracy, quality control, contamination, and scalability. However, the emergence of cutting-edge technologies has paved a way for a new era for pharmacy compounding, promising to redefine the way medications are prepared and delivered as pharmacy-tailored personalized medicines. In this multi-site study, more than 30 hospitals and community pharmacies from eight countries in Europe utilized a novel automated dosing approach inspired by 3D printing for the compounding of non-sterile propranolol hydrochloride tablets. CuraBlend <sup>®</sup> excipient base, a GMP-manufactured excipient base (pharma-ink) intended for automated compounding applications, was used. A standardized study protocol to test the automated dosing of tablets with variable weights was performed in all participating pharmacies in four different iterative phases. Integrated quality control was performed with an in-process scale and NIR spectroscopy supported by HPLC content uniformity measurements. In total, 6088 propranolol tablets were produced at different locations during this study. It was shown that the dosing accuracy of the process increased from about 90% to 100% from Phase 1 to Phase 4 by making improvements to the formulation and the hardware solutions. The results indicate that through this automated and quality controlled compounding approach, extemporaneous pharmacy manufacturing can take a giant leap forward towards automation and digital manufacture of dosage forms in hospital pharmacies and compounding pharmacies

The lipid droplet coat protein perilipin 5 also localizes to muscle mitochondria

Perilipin 5 (PLIN5/OXPAT) is a lipid droplet (LD) coat protein mainly present in tissues with a high fat-oxidative capacity, suggesting a role for PLIN5 in facilitating fatty acid oxidation. Here, we investigated the role of PLIN5 in fat oxidation in skeletal muscle. In human skeletal muscle, we observed that PLIN5 (but not PLIN2) protein content correlated tightly with OXPHOS content and in rat muscle PLIN5 content correlated with mitochondrial respiration rates on a lipid-derived substrate. This prompted us to examine PLIN5 protein expression in skeletal muscle mitochondria by means of immunogold electron microscopy and Western blots in isolated mitochondria. These data show that PLIN5, in contrast to PLIN2, not only localizes to LD but also to mitochondria, possibly facilitating fatty acid oxidation. Unilateral overexpression of PLIN5 in rat anterior tibialis muscle augmented myocellular fat storage without increasing mitochondrial density as indicated by the lack of change in protein content of five components of the OXPHOS system. Mitochondria isolated from PLIN5 overexpressing muscles did not possess increased fatty acid respiration. Interestingly though, 14C-palmitate oxidation assays in muscle homogenates from PLIN5 overexpressing muscles revealed a 44.8% (P = 0.05) increase in complete fatty acid oxidation. Thus, in mitochondrial isolations devoid of LD, PLIN5 does not augment fat oxidation, while in homogenates containing PLIN5-coated LD, fat oxidation is higher upon PLIN5 overexpression. The presence of PLIN5 in mitochondria helps to understand why PLIN5, in contrast to PLIN2, is of specific importance in fat oxidative tissues. Our data suggests involvement of PLIN5 in directing fatty acids from the LD to mitochondrial fatty acid oxidation

The South Atlantic Anticyclone as a key player for the representation of the tropical Atlantic climate in coupled climate models

The key role of the South Atlantic Anticyclone (SAA) on the seasonal cycle of the tropical Atlantic is investigated with a regionally coupled atmosphere–ocean model for two different coupled domains. Both domains include the equatorial Atlantic and a large portion of the northern tropical Atlantic, but one extends southward, and the other northwestward. The SAA is simulated as internal model variability in the former, and is prescribed as external forcing in the latter. In the first case, the model shows significant warm biases in sea surface temperature (SST) in the Angola-Benguela front zone. If the SAA is externally prescribed, these biases are substantially reduced. The biases are both of oceanic and atmospheric origin, and are influenced by ocean–atmosphere interactions in coupled runs. The strong SST austral summer biases are associated with a weaker SAA, which weakens the winds over the southeastern tropical Atlantic, deepens the thermocline and prevents the local coastal upwelling of colder water. The biases in the basins interior in this season could be related to the advection and eddy transport of the coastal warm anomalies. In winter, the deeper thermocline and atmospheric fluxes are probably the main biases sources. Biases in incoming solar radiation and thus cloudiness seem to be a secondary effect only observed in austral winter. We conclude that the external prescription of the SAA south of 20°S improves the simulation of the seasonal cycle over the tropical Atlantic, revealing the fundamental role of this anticyclone in shaping the climate over this region

Reactive Oxygen Species Production by Forward and Reverse Electron Fluxes in the Mitochondrial Respiratory Chain

Reactive oxygen species (ROS) produced in the mitochondrial respiratory chain (RC) are primary signals that modulate cellular adaptation to environment, and are also destructive factors that damage cells under the conditions of hypoxia/reoxygenation relevant for various systemic diseases or transplantation. The important role of ROS in cell survival requires detailed investigation of mechanism and determinants of ROS production. To perform such an investigation we extended our rule-based model of complex III in order to account for electron transport in the whole RC coupled to proton translocation, transmembrane electrochemical potential generation, TCA cycle reactions, and substrate transport to mitochondria. It fits respiratory electron fluxes measured in rat brain mitochondria fueled by succinate or pyruvate and malate, and the dynamics of NAD+ reduction by reverse electron transport from succinate through complex I. The fitting of measured characteristics gave an insight into the mechanism of underlying processes governing the formation of free radicals that can transfer an unpaired electron to oxygen-producing superoxide and thus can initiate the generation of ROS. Our analysis revealed an association of ROS production with levels of specific radicals of individual electron transporters and their combinations in species of complexes I and III. It was found that the phenomenon of bistability, revealed previously as a property of complex III, remains valid for the whole RC. The conditions for switching to a state with a high content of free radicals in complex III were predicted based on theoretical analysis and were confirmed experimentally. These findings provide a new insight into the mechanisms of ROS production in RC

Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates

NOTICE: This is the peer reviewed version of the following book chapter: Varela J. A., González-Rodríguez C., Saá C. (2014). Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates. In: Dixneuf P., Bruneau C. (eds) Ruthenium in Catalysis. Topics in Organometallic Chemistry, vol 48, pp. 237-287. Springer, Cham. [doi: 10.1007/3418_2014_81]. This article may be used for non-commercial purposes in accordance with Springer Verlag Terms and Conditions for self-archiving.Vinylidenes are high-energy tautomers of terminal alkynes and they can be stabilized by coordination with transition metals. The resulting metal-vinylidene species have interesting chemical properties that make their reactivity different to that of the free and metal π-coordinated alkynes: the carbon α to the metal is electrophilic whereas the β carbon is nucleophilic. Ruthenium is one of the most commonly used transition metals to stabilize vinylidenes and the resulting species can undergo a range of useful transformations. The most remarkable transformations are the regioselective anti-Markovnikov addition of different nucleophiles to catalytic ruthenium vinylidenes and the participation of the π system of catalytic ruthenium vinylidenes in pericyclic reactions. Ruthenium vinylidenes have also been employed as precatalysts in ring closing metathesis (RCM) or ring opening metathesis polymerization (ROMP). Allenylidenes could be considered as divalent radicals derived from allenes. In a similar way to vinylidenes, allenylidenes can be stabilized by coordination with transition metals and again ruthenium is one of the most widely used metals. Metalallenylidene complexes can be easily obtained from terminal propargylic alcohols by dehydration of the initially formed metal-hydroxyvinylidenes, in which the reactivity of these metal complexes is based on the electrophilic nature of Cα and Cγ, while Cβ is nucleophilic. Catalytic processes based on nucleophilic additions and pericyclic reactions involving the π system of ruthenium allenylidenes afford interesting new structures with high selectivity and atom economy

Status of Biodiversity in the Baltic Sea

The brackish Baltic Sea hosts species of various origins and environmental tolerances. These immigrated to the sea 10,000 to 15,000 years ago or have been introduced to the area over the relatively recent history of the system. The Baltic Sea has only one known endemic species. While information on some abiotic parameters extends back as long as five centuries and first quantitative snapshot data on biota (on exploited fish populations) originate generally from the same time, international coordination of research began in the early twentieth century. Continuous, annual Baltic Sea-wide long-term datasets on several organism groups (plankton, benthos, fish) are generally available since the mid-1950s. Based on a variety of available data sources (published papers, reports, grey literature, unpublished data), the Baltic Sea, incl. Kattegat, hosts altogether at least 6,065 species, including at least 1,700 phytoplankton, 442 phytobenthos, at least 1,199 zooplankton, at least 569 meiozoobenthos, 1,476 macrozoobenthos, at least 380 vertebrate parasites, about 200 fish, 3 seal, and 83 bird species. In general, but not in all organism groups, high sub-regional total species richness is associated with elevated salinity. Although in comparison with fully marine areas the Baltic Sea supports fewer species, several facets of the system's diversity remain underexplored to this day, such as micro-organisms, foraminiferans, meiobenthos and parasites. In the future, climate change and its interactions with multiple anthropogenic forcings are likely to have major impacts on the Baltic biodiversity