2,384 research outputs found
Unveiling operator growth in SYK quench dynamics
We study non-equilibrium dynamics induced by a sudden quench of strongly
correlated Hamiltonians with all-to-all interactions. By relying on a
Sachdev-Ye-Kitaev (SYK) based quench protocol, we show that the time evolution
of simple spin-spin correlation functions is highly sensitive to the degree of
locality of the corresponding operators, once an appropriate set of fundamental
fields is identified. By tracking the time-evolution of specific spin-spin
correlation functions and their decay, we argue that it is possible to
distinguish between operator hopping and operator growth dynamics; the latter
being a hallmark of quantum chaos in many-body quantum systems. Such
observation, in turn, could constitute a promising tool to probe the emergence
of chaotic behavior, rather accessible in state-of-the-art quench setups.Comment: v2: Fixed broken Unicode characters; REVTeX4-1, 13 pages, 14 figure
Bibliography of Balkan demography: the contribution of Italian studies
The working paper presents a selected bibliography on Balkan demography on featuring books and chapter from books, scientific articles, conference proceedings and conference papers, reports and other grey materials. The bibliography includes Italian authors who published both in Italian and a language other than Italian as well as foreign authors who published their works in Italian and/or in Italian journal
Granulocytes of sea anemone Actinia equina (Linnaeus, 1758) body fluid contain and release cytolysins forming plaques of lysis
The Cnidaria phylum includes organisms that are among the most poisonous animals. The exact composition of cnidarian bioactive molecules is not known in detail, but little is known on the cells that produce the toxins. Here we have shown that the presence of cytolysins is not exclusive of nematocysts. A plaque-forming assay was carried out with cell populations extracted from the percoled body fluid showed for the first time that anthozoan granulocytes are able to form plaque of lysis. We have partitioned the total population of free cells into three distinct discrete bands by discontinuous Percoll gradient, and we have identified six small different types cells: morular granulocytes; cells with large or small peripherical granules, granulocytes with irregular shape containing blue and red granules, cells showing one fine red granule of uniform size and, finally, cells with elongated shape and small dispersed granules. Cell lysate of each cellular band resulted cytolytic toward different erythrocytes types. SDS page analysis of the lysate cell fraction showed a predominant of 20 kDa that corresponds to the weight of the cytolytic equinatoxin. The nature of equinatoxins-related activity was demonstrated by inhibition experiments using bovine sphingomyelin
Family Visiting Restrictions and Postoperative Clinical Outcomes: A Retrospective Analysis
In the last two years, all hospitals have adopted restricted visitation policies due to the coronavirus disease 2019. The objective of this study was to assess the consequences of hospital visitation restrictions on the most common outcome measures on adult patients who underwent surgery. A retrospective study design was conducted according to the STrengthening the Reporting of OBservational studies in Epidemiology statements in 2021. Forty patients exposed to a no-visitors policy and forty unexposed patients (1:1) were enrolled. Patients who were not allowed to receive family visits were more likely to report disorientation/agitation episodes (n = 25, 62.5% vs. n = 12, 30.0%; p < 0.01), spend more sleepless nights (n = 10, 25.0% vs. n = 1, 2.5%; p < 0.01), be restrained (n = 8, 20.0% vs. n = 1, 2.5%; p = 0.02), incur device-removal incidents (n = 14, 35.0% vs. n = 5, 12.5%; p = 0.01) compared to unexposed patients. Conversely, pain episodes were significantly more frequent in the unexposed group (n = 7.1, SD = 7.9 vs. n = 2.4, SD = 2.8; p < 0.01), and there was lower clinical deterioration risk (NEWS of 0–4 average 19.5, SD = 12.2 evaluations vs. 12.3, SD = 8.6; p < 0.01) compared to exposed patients. According to the results, family visiting restrictions should be measured against their possible advantages in order to prevent negative outcomes for surgical patients and to improve the quality of care
Homodyne estimation of Gaussian quantum discord
We address the experimental estimation of Gaussian quantum discord for
two-mode squeezed thermal state, and demonstrate a measurement scheme based on
a pair of homodyne detectors assisted by Bayesian analysis which provides
nearly optimal estimation for small value of discord. Besides, though homodyne
detection is not optimal for Gaussian discord, the noise ratio to the ultimate
quantum limit, as dictacted by the quantum Cramer-Rao bound, is limited to
about 10 dB.Comment: 5+3 pages, 3 figures, published versio
Non-Gaussianity of quantum states: an experimental test on single-photon added coherent states
Non Gaussian states and processes are useful resources in quantum information
with continuous variables. An experimentally accessible criterion has been
proposed to measure the degree of non Gaussianity of quantum states, based on
the conditional entropy of the state with a Gaussian reference. Here we adopt
such criterion to characterise an important class of non classical states,
single-photon added coherent states. Our studies demonstrate the reliability
and sensitivity of this measure, and use it to quantify how detrimental is the
role of experimental imperfections in our realisation
Comprehensive Evaluation of the Volatomic Fingerprint of Saffron from Campania towards Its Authenticity and Quality
The volatile profiles of eight saffron samples (seven cultivated and one spontaneous) grown
in different geographical districts within the Campania region (southern Italy) were compared. Using
headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry (HS SPME/GC-MS), overall, 80 volatiles were identified in the eight landraces. Among them, safranal
and its isomers and other related compounds such as isophorones, which are not only key odorants
but also pharmacologically active metabolites, have been detected in all the investigated samples.
Principal Component Analysis performed on the volatiles’ compounds revealed that the spontaneous
sample turned out to be an outlier. In particular, the volatile organic compounds (VOCs) profile
of the spontaneous saffron presented four lilac aldehydes and four lilac alcohol isomers, which,
to the authors’ knowledge, have never been identified in the volatile signature of this spice. The
multivariate statistical analysis allowed the discrimination of the seven cultivate saffron ecotypes in
four well-separated clusters according to variety. Moreover, 20 VOCs, able to differentiate the clusters
in terms of single volatile metabolite, were discovered. Altogether, these results could contribute to
identifying possible volatile signature metabolites (biomarkers) or patterns that discriminate saffron
samples grown in Campania region on a molecular basis, encouraging future biodiversity programs
to preserve saffron landraces revealing valuable genetic resources.info:eu-repo/semantics/publishedVersio
Trichoderma: a multipurpose, plant-beneficial microorganism for eco-sustainable agriculture
Trichoderma is a cosmopolitan and opportunistic ascomycete fungal genus including species that are of interest to agriculture as direct biological control agents of phytopathogens. Trichoderma utilizes direct antagonism and competition, particularly in the rhizosphere, where it modulates the composition of and interactions with other microorganisms. In its colonization of plants, on the roots or as an endophyte, Trichoderma has evolved the capacity to communicate with the plant and produce numerous multifaceted benefits to its host. The intricacy of this plant-microorganism association has stimulated a marked interest in research on Trichoderma, ranging from its capacity as a plant growth promoter to its ability to prime local and systemic defence responses against biotic and abiotic stresses and to activate transcriptional memory affecting plant responses to future stresses. This Review discusses the ecophysiology and diversity of Trichoderma and the complexity of its relationships in the agroecosystem, highlighting its potential as a direct and indirect biological control agent, biostimulant and biofertilizer, which are useful multipurpose properties for agricultural applications. We also highlight how the present legislative framework might accommodate the demonstrated evidence of Trichoderma proficiency as a plant-beneficial microorganism contributing towards eco-sustainable agriculture
Normal traces and applications to continuity equations on bounded domains
In this work, we study several properties of the normal Lebesgue trace of vector fields introduced by the second and third author in [18] in the context of the energy conservation for the Euler equations in Onsager-critical classes. Among several properties, we prove that the normal Lebesgue trace satisfies the Gauss-Green identity and, by providing explicit counterexamples, that it is a notion sitting strictly between the distributional one for measure-divergence vector fields and the strong one for functions. These results are then applied to the study of the uniqueness of weak solutions for continuity equations on bounded domains, allowing to remove the assumption in [15] of global regularity up to the boundary, at least around the portion of the boundary where the characteristics exit the domain or are tangent. The proof relies on an explicit renormalization formula completely characterized by the boundary datum and the positive part of the normal Lebesgue trace. In the case when the characteristics enter the domain, a counterexample shows that achieving the normal trace in the Lebesgue sense is not enough to prevent non-uniqueness, and thus a assumption seems to be necessary for the uniqueness of weak solutions
Finite element micro-modelling for the characterization of inclined head joints archaeological masonry: the case of Villa Diomede in Pompeii
Villa Diomede is a great roman building located on the western corner of the modern archaeological site of Pompeii, built during III century BC and discovered between 1771 and 1774 during archaeological excavations. The system is composed by three levels: the road level, the garden level, which hosts the portico structure, and the underground level. The building includes diverse types of masonry with a wide range of unit shapes, dimensions and materials (i.e. tuff, limestone, volcanic stone, clay brick etc.). Besides, an unconventional tuff masonry type was observed on some structures of the garden; it reveals inclined head joints, whose structural function is still unknown.
The paper reports the numerical micro-modeling of this particular texture of masonry, where the constitutive materials (tuff units and mortar) are discretized. The main goal of the work is the assessment of inclined masonry joints as an aseismic detail compared with widespread traditional tuff running bond masonry.
Micro models of masonry wallettes were created assigning a non-linear constitutive behavior, i.e. total strain crack model (with a parabolic behavior in compression and an exponential softening behavior in tension, whereas damage due to tensile cracking was modeled adopting a rotating crack model). Moreover, brittle 2D interfaces were modeled between mortar and units at inclined joints surfaces. The paper focuses on numerical prediction of compressive response of masonry models subjected to uniaxial compressive tests.Postprint (published version
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