Tensor-network Study of Correlation-spreading Dynamics in the Two-dimensional Bose-Hubbard Model

Recent developments in analog quantum simulators based on cold atoms and trapped ions call for cross-validating the accuracy of quantum-simulation experiments with use of quantitative numerical methods; however, it is particularly challenging for dynamics of systems with more than one spatial dimension. Here we demonstrate that a tensor-network method running on classical computers is useful for this purpose. We specifically analyze real-time dynamics of the two-dimensional Bose-Hubbard model after a sudden quench starting from the Mott insulator by means of the infinite projected entangled pair state algorithm. Calculated single-particle correlation functions are found to be in good agreement with a recent experiment [Y. Takasu et al., Sci. Adv. 6, eaba9255 (2020)]. By estimating the phase and group velocities from the single-particle and density-density correlation functions, we predict how these velocities vary in the moderate interaction region, which serves as a quantitative benchmark for future experiments.

Liquid-Crystal Ordering and Microphase Separation in the Lamellar Phase of Rod-Coil-Rod Triblock Copolymers. Molecular Theory and Computer Simulations

A molecular model of the orientationally ordered lamellar phase exhibited by asymmetric rod-coil-rod triblock copolymers has been developed using the density-functional approach and generalizing the molecular-statistical theory of rod-coil diblock copolymers. An approximate expression for the free energy of the lamellar phase has been obtained in terms of the direct correlation functions of the system, the Flory-Huggins parameter and the Maier-Saupe orientational interaction potential between rods. A detailed derivation of several rod-rod and rod-coil density-density correlation functions required to evaluate the free energy is presented. The orientational and translational order parameters of rod and coil segments depending on the temperature and triblock asymmetry have been calculated numerically by direct minimization of the free energy. Different structure and ordering of the lamellar phase at high and low values of the triblock asymmetry is revealed and analyzed in detail. Asymmetric rod-coil-rod triblock copolymers have been simulated using the method of dissipative particle dynamics in the broad range of the Flory-Huggins parameter and for several values of the triblock asymmetry. It has been found that the lamellar phase appears to be the most stable one at strong segregation. The density distribution of the coil segments and the segments of the two different rods have been determined for different values of the segregation strength. The simulations confirm the existence of a weakly ordered lamellar phase predicted by the density-functional theory, in which the short rods separate from the long ones and are characterized by weak positional ordering.

COMPOSITION AND COMMUNITY STRUCTURE OF COPEPOD IN KAKAP RIVER ESTUARY, KUBU RAYA DISTRICT WEST BORNEO

The research of composition and community structure of copepods in Kakap river estuary, Kubu Raya District, West Borneo was conducted from October to December 2020. The purpose of this study is to determine the composition and the community structure of copepod in Kakap river estuary, Kubu Raya District, West Borneo. This study used a purposive sampling method at four stations. Copepod samples were taken using plankton net. During the research, the total number of copepods that have been identified from 4 stations are 11 species from 3 orders, 4 families and 8 genera. Copepoda that has been obtained has the composition, namly Cyclopoids 5 species, Harpacticoida 3 species, Calanoida 2 species. The copepod density in Kakap river estuary ranged from 7,9-103,3 Ind / l, the diversity index (H ') ranged from 0 to 1.9, the evenness index (E) ranged from 0 - 0,9 and the dominance index (C) ranged from 0,2 - 1. The result of copepod density correlation analysis is that negatively correlated with -1,000 current parameter and positively correlated with the DO parameter, which is 0,800. The research of composition and community structure of copepods in Kakap river estuary, Kubu Raya District, West Borneo was conducted from October to December 2020. The purpose of this study is to determine the composition and the community structure of copepod in Kakap river estuary, Kubu Raya District, West Borneo. This study used a purposive sampling method at four stations. Copepod samples were taken using plankton net. During the research, the total number of copepods that have been identified from 4 stations are 11 species from 3 orders, 4 families and 8 genera. Copepoda that has been obtained has the composition, namly Cyclopoids 5 species, Harpacticoida 3 species, Calanoida 2 species. The copepod density in Kakap river estuary ranged from 7,9-103,3 Ind / l, the diversity index (H ') ranged from 0 to 1.9, the evenness index (E) ranged from 0 - 0,9 and the dominance index (C) ranged from 0,2 - 1. The result of copepod density correlation analysis is that negatively correlated with -1,000 current parameter and positively correlated with the DO parameter, which is 0,800.

Micro-CT-Based Quantification of Extracted Thrombus Burden Characteristics and Association With Angiographic Outcomes in Patients With ST-Elevation Myocardial Infarction: The QUEST-STEMI Study

Background: Angiographic detection of thrombus in STEMI is associated with adverse outcomes. However, routine thrombus aspiration failed to demonstrate the anticipated benefit. Hence, management of high coronary thrombus burden remains challenging. We sought to assess for the first time extracted thrombotic material characteristics utilizing micro-computed tomography (micro-CT).Methods: One hundred thirteen STEMI patients undergoing thrombus aspiration were enrolled. Micro-CT was undertaken to quantify retrieved thrombus volume, surface, and density. Correlation of these indices with angiographic and electrocardiographic outcomes was performed.Results: Mean aspirated thrombus volume, surface, and density (±standard deviation) were 15.71 ± 20.10 mm3, 302.89 ± 692.54 mm2, and 3139.04 ± 901.88 Hounsfield units, respectively. Aspirated volume and surface were significantly higher (p < 0.001) in patients with higher angiographic thrombus burden. After multivariable analysis, independent predictors for thrombus volume were reference vessel diameter (RVD) (p = 0.011), right coronary artery (RCA) (p = 0.039), and smoking (p = 0.027), whereas RVD (p = 0.018) and RCA (p = 0.019) were predictive for thrombus surface. Thrombus volume and surface were independently associated with distal embolization (p = 0.007 and p = 0.028, respectively), no-reflow phenomenon (p = 0.002 and p = 0.006, respectively), and angiographically evident residual thrombus (p = 0.007 and p = 0.002, respectively). Higher thrombus density was correlated with worse pre-procedural TIMI flow (p < 0.001). Patients with higher aspirated volume and surface developed less ST resolution (p = 0.042 and p = 0.023, respectively).Conclusions: Angiographic outcomes linked with worse prognosis were more frequent among patients with larger extracted thrombus. Despite retrieving larger thrombus load in these patients, current thrombectomy devices fail to deal with thrombotic material adequately. Further studies of novel thrombus aspiration technologies are warranted to improve patient outcomes.Clinical Trial Registration: QUEST-STEMI trial ClinicalTrials.gov number: NCT03429608 Date of registration: February 12, 2018. The study was prospectively registered.

Correlation of Demographics, Healthcare Availability, and COVID-19 Outcome: Indonesian Ecological Study

Objective: To analyze the correlation between demographic and healthcare availability indicators with COVID-19 outcome among Indonesian provinces.Methods: We employed an ecological study design to study the correlation between demographics, healthcare availability, and COVID-19 indicators. Demographic and healthcare indicators were obtained from the Indonesian Health Profile of 2019 by the Ministry of Health while COVID-19 indicators were obtained from the Indonesian COVID-19 website in August 31st 2020. Non-parametric correlation and multivariate regression analyses were conducted with IBM SPSS 23.0.Results: We found the number of confirmed cases and case growth to be significantly correlated with demographic indicators, especially with distribution of age groups. Confirmed cases and case growth was significantly correlated (p < 0.05) with population density (correlation coefficient of 0.461 and 0.491) and proportion of young people (−0.377; −0.394). Incidence and incidence growth were correlated with ratios of GPs (0.426; 0.534), hospitals (0.376; 0.431), primary care clinics (0.423; 0.424), and hospital beds (0.472; 0.599) per capita. For mortality, case fatality rate (CFR) was correlated with population density (0.390) whereas mortality rate was correlated with ratio of hospital beds (0.387). Multivariate analyses found confirmed case independently associated with population density (β of 0.638) and demographic structure (−0.289). Case growth was independently associated with density (0.763). Incidence growth was independently associated with hospital bed ratio (0.486).Conclusion: Pre-existing inequality of healthcare availability correlates with current reported incidence and mortality rate of COVID-19. Lack of healthcare availability in some provinces may have resulted in artificially low numbers of cases being diagnosed, lower demands for COVID-19 tests, and eventually lower case-findings.

Joint assessment of density correlations and fluctuations for analysing spatial tree patterns

Inferring the processes underlying the emergence of observed patterns is a key challenge in theoretical ecology. Much effort has been made in the past decades to collect extensive and detailed information about the spatial distribution of tropical rainforests, as demonstrated, e.g. in the 50 ha tropical forest plot on Barro Colorado Island, Panama. These kinds of plots have been crucial to shed light on diverse qualitative features, emerging both at the single-species or the community level, like the spatial aggregation or clustering at short scales. Here, we build on the progress made in the study of the density correlation functions applied to biological systems, focusing on the importance of accurately defining the borders of the set of trees, and removing the induced biases. We also pinpoint the importance of combining the study of correlations with the scale dependence of fluctuations in density, which are linked to the well-known empirical Taylor’s power law. Density correlations and fluctuations, in conjunction, provide a unique opportunity to interpret the behaviours and, possibly, to allow comparisons between data and models. We also study such quantities in models of spatial patterns and, in particular, we find that a spatially explicit neutral model generates patterns with many qualitative features in common with the empirical ones.

Change of nitrogen regime of gray forest large-sawn-light-ber-soil soil under the influence at different systems fertilizer and chemical land-reclamation

The results of research in a stationary study, based in 1992 on gray forest coarse-grained loamy soil, on the impact of long-term chemical reclamation and0,0 various supply systems (mineral, organic, organo-mineral) on the nitrogen regime. Nitrogen is extremely important in agriculture, as all processes, photosynthesis, volume of substances and distribution of the level of yield and its quality are impossible without this element. In the total coverage of the country, the share of soils of forest origin exceeds 33 %, and among agricultural lands – 25 %. Given the content of humus and its total reserves, the integrated indicator of soil formation and the most important characteristic that determines the overall habit of the soil, in the articles above, change it from the above factors. It can also be shown that the content of gross nitrogen reflects the humus content, which is determined and differs from the humus content of the residual. There is a high density correlation between these indicators for all different studies (r = 0,991). The obtained data indicate that only with the use of greens and by-products of precursors and measured doses of mineral fertilizers with the use of liming achieved by the size of the total nitrogen to the initial level. The growth of the composition is 0,36 – 0,45 t / ha and in this case we can state the expansion of its reproduction. Only after mineralization nitrogen of organic compounds becomes available to plants. The form of nitrogen, which is easily hydrolyzed, is a fairly reliable indicator of the provision of this element. To classify the test content with the content of mobile compounds 81,2 – 103 mg / kg belong to the user groups with a very high degree of supply, but the degree hydrolyzes organic substances in high quantities (9,6 – 10,2 %). With the combined use of green manures, non-marketable plant products, single doses of mineral fertilizers in a combination of lime achieved growth of 27,5 % on the restoration to control of this form of nitrogen. For the above complex of nutrients at an increased content of 16,5 mg/kg to control the amount of N-NO3- + N-NH4 +, as well as 7,4 mg / kg of nitrifying capacity of the soil. The studied gray forest soils belong to the group of soils with low humus content and its total reserves, which are inherited from the original pedogenesis and modern soil formation processes. Under the influence of a set of agronomic measures for a long time the type of humus does not change, which indicates the invariability of the direction of soil formation

Эффекты микрофазового разделения и корреляции типа плотность-плотность в аморфных полимерных пленках

The topology of density fluctuations on the surface of amorphous films obtained from solutions of some flexible-chain polymers has been studied using electron microscopy data in the submicron and micron scale ranges. It is shown that as the initial concentration of solutions increases, the effects of microphase separation in films increase due to the self-organization of aggregates (clusters) of macromolecules: anisotropy, long-range order, and correlation length of density fluctuations increase. Self-organization ends with the formation of an infinite cluster of particles, periodically-inhomogeneous in density and occupying ~ 30% of the surface of the films. The density – density correlation function of such a cluster on the ~ ξ scale has a universal form that does not depend on the composition and molecular weight of the polymer.