693 research outputs found
High-resolution correlation of coastal cliff sections in the Lagos- Portimao Formation (Lower - Middle Miocene, central Algarve, Portugal)
This paper describes a high-resolution stratigraphic correlation scheme for the early to middle Miocene Lagos-Portimão
Formation of central Algarve, southern Portugal.
The Lagos Portimão-Formation of central Algarve is a 60 m thick package of horizontally bedded siliciclastics and carbonates. The bryozoan and mollusc dominated biofacies is typical of a shallow marine, warm-temperate climatic environment. We define four stratigraphic marker beds based on biofacies, lithology, and gamma-ray signatures. Marker bed 1 is a reddish shell bed composed predominantly of bivalve shells in various stages of fragmentation. Marker bed 2 is a fossiliferous sandstone / sandy rudstone characterized by bryozoan masses. Marker bed 3 is also a fossiliferous sandstone with abundant larger foraminifers and foliate bryozoans. Marker bed 4 is composed of three distinct layers; two fossiliferous sandstones with an intercalated shell bed. The upper sandstone unit displays thickets of the bryozoan Celleporaria palmate associated with the coral Culizia parasitica.
This stratigraphic framework allows to correlate isolated outcrops within the stratigraphic context of the Lagos-Portimão
Formation and to establish high resolution chronostratigraphic Sr-isotopic dating
Gaussian excitations model for glass-former dynamics and thermodynamics
We describe a model for the thermodynamics and dynamics of glass-forming
liquids in terms of excitations from an ideal glass state to a Gaussian
manifold of configurationally excited states. The quantitative fit of this
three parameter model to the experimental data on excess entropy and heat
capacity shows that ``fragile'' behavior, indicated by a sharply rising excess
heat capacity as the glass transition is approached from above, occurs in
anticipation of a first-order transition -- usually hidden below the glass
transition -- to a ``strong'' liquid state of low excess entropy. The dynamic
model relates relaxation to a hierarchical sequence of excitation events each
involving the probability of accumulating sufficient kinetic energy on a
separate excitable unit. Super-Arrhenius behavior of the relaxation rates, and
the known correlation of kinetic with thermodynamic fragility, both follow from
the way the rugged landscape induces fluctuations in the partitioning of energy
between vibrational and configurational manifolds. A relation is derived in
which the configurational heat capacity, rather than the configurational
entropy of the Adam Gibbs equation, controls the temperature dependence of the
relaxation times, and this gives a comparable account of the experimental
observations.Comment: 21 pp., 17 fig
Bottlenecks to vibrational energy flow in OCS: Structures and mechanisms
Finding the causes for the nonstatistical vibrational energy relaxation in
the planar carbonyl sulfide (OCS) molecule is a longstanding problem in
chemical physics: Not only is the relaxation incomplete long past the predicted
statistical relaxation time, but it also consists of a sequence of abrupt
transitions between long-lived regions of localized energy modes. We report on
the phase space bottlenecks responsible for this slow and uneven vibrational
energy flow in this Hamiltonian system with three degrees of freedom. They
belong to a particular class of two-dimensional invariant tori which are
organized around elliptic periodic orbits. We relate the trapping and
transition mechanisms with the linear stability of these structures.Comment: 13 pages, 13 figure
Adaptive walks on time-dependent fitness landscapes
The idea of adaptive walks on fitness landscapes as a means of studying
evolutionary processes on large time scales is extended to fitness landscapes
that are slowly changing over time. The influence of ruggedness and of the
amount of static fitness contributions are investigated for model landscapes
derived from Kauffman's landscapes. Depending on the amount of static
fitness contributions in the landscape, the evolutionary dynamics can be
divided into a percolating and a non-percolating phase. In the percolating
phase, the walker performs a random walk over the regions of the landscape with
high fitness.Comment: 7 pages, 6 eps-figures, RevTeX, submitted to Phys. Rev.
Electron attachment to SF6 and lifetimes of SF6- negative ions
We study the process of low-energy electron capture by the SF6 molecule. Our
approach is based on the model of Gauyacq and Herzenberg [J. Phys. B 17, 1155
(1984)] in which the electron motion is coupled to the fully symmetric
vibrational mode through a weakly bound or virtual s state. By tuning the two
free parameters of the model, we achieve an accurate description of the
measured electron attachment cross section and good agreement with vibrational
excitation cross sections of the fully symmetric mode. An extension of the
model provides a limit on the characteristic time of intramolecular vibrational
relaxation in highly-excited SF6-. By evaluating the total vibrational spectrum
density of SF6-, we estimate the widths of the vibrational Feshbach resonances
of the long-lived negative ion. We also analyse the possible distribution of
the widths and its effect on the lifetime measurements, and investigate
nonexponential decay features in metastable SF6-.Comment: 22 pages, 10 figures, submitted to Phys. Rev.
Report from the CVOT Summit 2020: new cardiovascular and renal outcomes
The 6th Cardiovascular Outcome Trial (CVOT) Summit “Cardiovascular and Renal Outcomes 2020” was the first to be held virtually on October 29–30, 2020. As in previous years, this summit served as reference meeting for in-depth discussions on the topic of recently completed and presented major outcome trials. This year, focus was placed on the outcomes of VERTIS-CV, EMPEROR-Reduced, DAPA-CKD, and FIDELIO-DKD. Trial implications for diabetes management and the impact on new treatment algorithms were highlighted for diabetologists, cardiologists, endocrinologists, nephrologists, and general practitioners. Discussion evolved from major outcome trials using SGLT-2 inhibitors for treatment and prevention of heart failure and chronic kidney disease in people with and without diabetes, to additional therapy options for chronic kidney disease with a novel mineralocorticoid receptor antagonist. Furthermore, challenges in diabetes management like COVID-19 and obesity, as well as novel treatment strategies and guidelines, were discussed. The 7th Cardiovascular Outcome Trial Summit will be held virtually on November, 18–19, 2021 (http://www.cvot.org)
Secretion of beta-human chorionic gonadotropin by non-small cell lung cancer: a case report
<p>Abstract</p> <p>Introduction</p> <p>We describe a case of non-small cell lung cancer that was found to stain positive for beta-human chorionic gonadotropin on immunohistochemistry. Only a few case reports have described lung cancers that secrete beta-human chorionic gonadotropin.</p> <p>Case presentation</p> <p>A 68-year-old Caucasian man presented with symptoms of weakness, fatigue and weight loss for the past two months. On examination, he was found to have generalized lymphadenopathy, and radiologic workup revealed numerous metastases in the lungs, liver and kidneys. Biopsy of the supraclavicular lymph node revealed metastatic large cell lung cancer with beta-human chorionic gonadotropin hormone positivity. The serum beta-human chorionic gonadotropin level was 11,286 mIU/ml (upper limit of normal, 0.5 mIU/ml in non-pregnant females). He was diagnosed with stage 4 lung non-small cell lung cancer. The patient refused chemotherapy. He was discharged home with hospice care.</p> <p>Conclusion</p> <p>The markedly elevated serum values of beta-human chorionic gonadotropin initially prompted the medical team to investigate germinal tumors. In the presence of a negative testicular ultrasound, workup was performed to find an extratesticular source of the tumor. Finally, the diagnosis was made with a tissue biopsy. This case illustrates that atypical markers can be seen in many cancers, emphasizing the role of immunohistochemistry and tissue biopsy in establishing the diagnosis.</p
Star Architecture as Socio-Material Assemblage
Taking inspiration from new materialism and assemblage, the chapter deals with star architects and iconic buildings as socio-material network effects that do not pre-exist action, but are enacted in practice, in the materiality of design crafting and city building. Star architects are here conceptualized as part of broader assemblages of actors and practices ‘making star architecture’ a reality, and the buildings they design are considered not just as unique and iconic objects, but dis-articulated as complex crafts mobilizing skills, technologies, materials, and forms of knowledge not necessarily ascribable to architecture. Overcoming narrow criticism focusing on the symbolic order of icons as unique creations and alienated repetitions of capitalist development, the chapter’s main aim is to widen the scope of critique by bridging culture and economy, symbolism and practicality, making star architecture available to a broad, fragmented arena of (potential) critics, unevenly equipped with critical tools and differentiated experiences
Prevention, diagnosis, therapy and follow-up care of sepsis: 1st revision of S-2k guidelines of the German Sepsis Society (Deutsche Sepsis-Gesellschaft e.V. (DSG)) and the German Interdisciplinary Association of Intensive Care and Emergency Medicine (Deutsche Interdisziplinäre Vereinigung für Intensiv- und Notfallmedizin (DIVI))
Practice guidelines are systematically developed statements and recommendations that assist the physicians and patients in making decisions about appropriate health care measures for specific clinical circumstances taking into account specific national health care structures. The 1st revision of the S-2k guideline of the German Sepsis Society in collaboration with 17 German medical scientific societies and one self-help group provides state-of-the-art information (results of controlled clinical trials and expert knowledge) on the effective and appropriate medical care (prevention, diagnosis, therapy and follow-up care) of critically ill patients with severe sepsis or septic shock. The guideline had been developed according to the “German Instrument for Methodological Guideline Appraisal” of the Association of the Scientific Medical Societies (AWMF). In view of the inevitable advancements in scientific knowledge and technical expertise, revisions, updates and amendments must be periodically initiated. The guideline recommendations may not be applied under all circumstances. It rests with the clinician to decide whether a certain recommendation should be adopted or not, taking into consideration the unique set of clinical facts presented in connection with each individual patient as well as the available resources
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