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Delacour Jean. Le Tangara de Paradis (Tangara chilensis). In: La Terre et La Vie, Revue d'Histoire naturelle, tome 2, n°1, 1948. pp. 4-8.

The plasticity of a synapse in the molluscan peripheral nervous system was examined under a variety of experimental, physiological, and pharmacological conditions. These studies employed the isolated salivary glands and attached buccal ganglia of the freshwater snail Helisoma. Action potentials evoked in buccal neuron 4 normally evoke a large excitatory postsynaptic potential (EPSP) which drives an action potential in gland secretory cells. In order to measure modulation of the EPSP, action potential generation in gland cells was prevented by bathing the preparation in low calcium, high magnesium salines. The relationship between the gland EPSP amplitude and specific physiological properties of neuron 4 was analyzed. In common with some central molluscan synapses, the EPSP was found to be strongly influenced by the membrane potential of neuron 4. Specifically, its amplitude was reduced by hyperpolarization of the neuron 4 soma. The relationship between EPSP amplitude and somatic potential of neuron 4 was linear in the range from resting potential (-47 +/- 6mV) to -100 mV. Furthermore, the EPSP amplitude was directly proportional to the action potential half-width of neuron 4. In order to evaluate the possible physiological role of this action potential/EPSP relationship, we examined whether gland EPSPs are modulated during the spike broadening that occurs in both spontaneous burst activity and imposed impulse trains. The preceding action potential/EPSP relationship was maintained under both of these conditions, i.e., EPSP magnitude increased as spikes broadened during bursts or trains. The peptidergic modulation of neuroglandular transmission was also examined. The molluscan peptide SCPB was found to depolarize neuron 4 and an increase in EPSP amplitude was concomitantly observed.(ABSTRACT TRUNCATED AT 250 WORDS)

AbstractThis paper considers the discrete-time risk model with insurance risk and financial risk in some dependence structures. Under assumptions that the insurance risks are heavy tailed (belong to the intersection of the long-tailed class and the dominatedly varying-tailed class) and the financial risks satisfy some moment conditions, the asymptotic and uniformly asymptotic relations for the finite-time and ultimate ruin probabilities are derived.

International audience; Although the problem of computing frequent queries in relational databases is known to be intractable, it has been argued in our previous work that using functional and inclusion dependencies, computing frequent conjunctive queries becomes feasible for databases operating over a star schema. However, the implementation considered in this previous work showed severe limitations for large fact tables. The main contribution of this paper is to overcome these limitations using appropriate auxiliary tables. We thus introduce a novel algorithm, called Frequent Query Finder (FQF), and we report on experiments showing that our algorithm allows for an effective and efficient computation of frequent queries.

Nanoparticles and nanostructured materials represent an active area of research for their impact in many application fields [...]

A temporal model describes processes as a sequence of observable events characterised by distinguishable actions in time. Conformance checking allows these models to determine whether any sequence of temporally ordered and fully-observable events complies with their prescriptions. The latter aspect leads to Explainable and Trustworthy AI, as we can immediately assess the flaws in the recorded behaviours while suggesting any possible way to amend the wrongdoings. Recent findings on conformance checking and temporal learning lead to an interest in temporal models beyond the usual business process management community, thus including other domain areas such as Cyber Security, Industry 4.0, and e-Health. As current technologies for accessing this are purely formal and not ready for the real world returning large data volumes, the need to improve existing conformance checking and temporal model mining algorithms to make Explainable and Trustworthy AI more efficient and competitive is increasingly pressing. To effectively meet such demands, this paper offers KnoBAB, a novel business process management system for efficient Conformance Checking computations performed on top of a customised relational model. This architecture was implemented from scratch after following common practices in the design of relational database management systems. After defining our proposed temporal algebra for temporal queries (xtLTLf), we show that this can express existing temporal languages over finite and non-empty traces such as LTLf. This paper also proposes a parallelisation strategy for such queries, thus reducing conformance checking into an embarrassingly parallel problem leading to super-linear speed up. This paper also presents how a single xtLTLf operator (or even entire sub-expressions) might be efficiently implemented via different algorithms, thus paving the way to future algorithmic improvements. Finally, our benchmarks highlight that our proposed implementation of xtLTLf (KnoBAB) outperforms state-of-the-art conformance checking software running on LTLf logic.

Abstract The effect of age (22, 30, 38, and 46 days) on Beijing duck breast myosin gels was investigated. The results showed that the water holding capacity (WHC) and gel strength were markedly improved at the age of 30 days. Differential scanning calorimetry suggested that the myosin thermal ability increased at the age of 30 and 38 days (p<0.05). A compact myosin gel network with thin cross-linked strands and small regular cavities formed at the age of 30 days, which was resulted from the higher content of hydrophobic interactions and disulfide bonds. Moreover, the surface hydrophobicity of myosin extracted from a 30-day-old duck breast decreased significantly under temperature higher than 80°C (p<0.05). This study illustrated that myosin extracted from a 30-day-old duck’s breast enhanced and stabilized the WHC, thermal stability and molecular forces within the gel system. It concluded that age is an essential influencing factor on the myosin thermal stability and gel quality of Beijing duck due to the transformation of fibrils with different myosin character.

AbstractThe Jahn–Teller (JT) effect, through geometric deformation of molecules or local ionic lattices, lowers the overall energy of the system by removing electron degeneracy from partially occupied orbitals. Crystal symmetry lowered by JT distortion inevitably creates multiple variants of elastic and orbital-anisotropic states. Visualization and control of the domain/wall textures create a cornerstone to understand various correlated phenomena and explore wall properties. Here, we report the real-space observation of JT phonon and orbiton-related domains in a LaMnO3 thin film using confocal Raman spectromicroscopy. The characteristic symmetries of the JT-originated Raman modes allow us to detect and visualize the local population and orientation of the JT planes. Combined with a crystal structural analysis, we find that the formation of ferroelastic domains with W or W’ walls provides the basic framework for understanding JT domain textures. Furthermore, we demonstrate the JT domains can be manipulated by applying local external stress. Our findings provide a useful pathway for mechanically-tunable orbitronic applications.

Introduction and aims: The complement system may play a part in the pathogenesis of amyloid disorders. The primary aim of the study was to analyse the relationship between transthyretin renal amyloidosis (ATTR) and the complement system. The secondary aim was to find potential clinical and morphologic features in ATTR amyloidosis associated with complement activation. Methods: We performed a retrospective cohort observational study in patients with renal amyloidosis submitted to kidney biopsy and complement measurements from January 2005 to June 2016. We compared clinical and laboratory results in different types of amyloidosis using the Kruskal-Wallis or Fisher's exact test. We performed a subgroup analysis in ATTR amyloidosis patients, comparing patients with normal and low complement serum levels in terms of clinical, laboratory, and morphologic characteristics, using the Mann-Whitney test or Fisher's exact test. Results: We included 42 patients in the analysis: 15 patients had ATTR amyloid deposits, 16 AA amyloid deposits and 11 AL amyloid deposits (all AL λ). A total of ten patients presented low C3 (6 ATTR; 3 AL; 1 AA). None of the patients had low C4 serum levels. Of the 15 Caucasian patients with renal ATTR amyloidosis, 6 (40%) presented low C3. Those patients had a higher sclerotic glomeruli number and 5 out of 6 had C3 deposits in immunofluorescence. Discussion: In our study, 40% of patients with renal ATTR amyloidosis showed complement consumption or activation, which led us to suspect that ATTR deposits can lead to systemic activation of the alternative complement pathway. It remains to be elucidated if this activation injures peripheral nerves and the kidney. Conclusions: C3 determinations can prove to be a useful tool for predicting renal involvement and glomerulosclerosis in TTR amyloidosis patients.

Why are the epidemic patterns of COVID-19 so different among different cities or countries which are similar in their populations, medical infrastructures, and people's behavior? Why are forecasts or predictions made by so-called experts often grossly wrong, concerning the numbers of people who get infected or die? The purpose of this study is to better understand the stochastic nature of an epidemic disease, and answer the above questions. Much of the work on infectious diseases has been based on "SIR deterministic models," (Kermack and McKendrick:1927.) We will explore stochastic models that can capture the essence of the seemingly erratic behavior of an infectious disease. A stochastic model, in its formulation, takes into account the random nature of an infectious disease. The stochastic model we study here is based on the "birth-and-death process with immigration" (BDI for short), which was proposed in the study of population growth or extinction of some biological species. The BDI process model ,however, has not been investigated by the epidemiology community. The BDI process is one of a few birth-and-death processes, which we can solve analytically. Its time-dependent probability distribution function is a "negative binomial distribution" with its parameter $r$ less than $1$. The "coefficient of variation" of the process is larger than $\sqrt{1/r} > 1$. Furthermore, it has a long tail like the zeta distribution. These properties explain why infection patterns exhibit enormously large variations. The number of infected predicted by a deterministic model is much greater than the median of the distribution. This explains why any forecast based on a deterministic model will fail more often than not. 28 pages, 14 figures