Miracle-dz/UniFAR-FTUs huggingface dataset:
Calibrating and Simulating Copula Functions in Financial Applications

Copula functions can be utilized in financial applications to determine the dependence structure of the financial asset returns in the portfolio. Empirical evidence has proved the inadequacy of the multi-normal distribution, traditionally adopted to model the financial asset returns distribution. Copula functions can be employed in a flexible way for building efficient algorithms and to simulate a more adequate distribution of the financial assets. This paper aims to describe some simple statistical procedures currently employed to calibrate the copula functions to the financial market data. Furthermore, we present some useful methods for choosing which copula function better fits the real financial data. Also, some algorithms to simulate random variates from certain types of copula functions are illustrated. Finally, for illustration purposes, the previous procedures described are applied to two Italian equities. In particular, we show how to generate efficient Monte Carlo scenarios of equity log-returns in the bivariate case using different types of copula functions.
Time dependence of negative and positive photoconductivity for Si δ-doped AlGaAs/InGaAs/AlGaAs quantum well under various temperatures and various incident photon energies and intensities

Si δ-doped AlGaAs/InGaAs/AlGaAs quantum well (QW) structure is commonly adopted as one of the core elements in modern electric and optoelectronic devices. Here, the time dependent photoconductivity spectra along the active InGaAs QW channel in a dual and symmetric Si δ-doped AlGaAs/InGaAs/AlGaAs QW structure are systematically studied under various temperatures (T = 80–300 K) and various incident photon energies (E in = 1.10–1.88 eV) and intensities. In addition to positive photoconductivity, negative photoconductivity (NPC) was observed and attributed to two origins. For T = 180–240 K with E in = 1.51–1.61 eV, the trapping of the photo-excited electrons by the interface states located inside the conduction band of InGaAs QW layer is one of the origins for NPC curves. For T = 80–120 K with E in = 1.10–1.63 eV, the photoexcitation of the excess ‘supersaturated’ electrons within the active InGaAs QW caused by the short cooling process is another origin.
Maternal haemoglobin levels in pregnancy and child DNA methylation: a study in the pregnancy and childhood epigenetics consortium

ABSTRACT Altered maternal haemoglobin levels during pregnancy are associated with pre-clinical and clinical conditions affecting the fetus. Evidence from animal models suggests that these associations may be partially explained by differential DNA methylation in the newborn with possible long-term consequences. To test this in humans, we meta-analyzed the epigenome-wide associations of maternal haemoglobin levels during pregnancy with offspring DNA methylation in 3,967 newborn cord blood and 1,534 children and 1,962 adolescent whole-blood samples derived from 10 cohorts. DNA methylation was measured using Illumina Infinium Methylation 450K or MethylationEPIC arrays covering 450,000 and 850,000 methylation sites, respectively. There was no statistical support for the association of maternal haemoglobin levels with offspring DNA methylation either at individual methylation sites or clustered in regions. For most participants, maternal haemoglobin levels were within the normal range in the current study, whereas adverse perinatal outcomes often arise at the extremes. Thus, this study does not rule out the possibility that associations with offspring DNA methylation might be seen in studies with more extreme maternal haemoglobin levels.
Fecal pellets of giant clams as a route for transporting Symbiodiniaceae to corals

Because more than 80% of species of gamete-spawning corals, including most Acroporidae species, do not inherit Symbiodiniaceae from their parents, they must acquire symbiont cells from sources in their environment. To determine whether photosynthetically competent Symbiodiniaceae expelled as fecal pellets from giant clams are capable of colonizing corals, we conducted laboratory experiments in which planula larvae of Acropora tenuis were inoculated with the cells in fecal pellets obtained from Tridacna crocea. T. crocea fecal pellets were administered once a day, and three days later, cells of Symbiodiniaceae from the fecal pellets had been taken up by the coral larvae. T. crocea fecal pellets were not supplied from the 4th day until the 8th day, and the cell densities in the larvae increased until the 8th day, which indicated the successful colonization by Symbiodiniaceae. The control group exhibited the highest mean percentage of larvae (100%) that were successfully colonized by culture strains of Symbiodiniaceae, and larvae inoculated with fecal pellets reached a colonization percentage of 66.7 ~ 96.7% on the 8th day. The highest colonization rate was achieved with the fecal pellets containing cells with high photosynthetic competency (Fv/Fm). Interestingly, the genetic composition of Symbiodiniaceae in the larvae retrieved on the 8th day differed from that in the fecal pellets and showed exclusive domination of the genus Symbiodinium. A minor but significant population of the genus Cladocopium in the fecal pellets was not inherited by the larvae. These experiments provided the first demonstration that the Symbiodiniaceae from tridacnine clams provided via fecal pellets can colonize and even proliferate in coral larvae.
Spatio-temporal sublittoral macrobenthic distribution and dominant species in Guanabara Bay, Rio de Janeiro, Brazil.

Soft-bottom macrobenthic invertebrates are sensitive to natural or anthropogenic changes in aquatic ecosystems. The distribution patterns of sublittoral macrobenthic species in Guanabara Bay were studied from 2005 to 2007. Samples were collected at ten stations during six surveys throughout the rainfall regime (dry, early and late rainy). Ten replicates were collected at each station by Gravity corer or skin diving. Van Dorn bottles (bottom water) and by Ekman sediment sampler (granulometry) provided material for abiotic data. Stations were grouped into sectors (Entrance, Intermediary and Inner) based on abiotic data and location. The Redundancy Analysis (RDA) and Parsimonious RDA for all years and each annual cycle showed indicator taxa with high dominance in each sector. PERMANOVA indicated a regular seasonality between the surveys for the first annual cycle (p <0.05), and an atypical pattern for the second (p> 0.05), possibly due the low rainfall observed during this period. The mosaic of soft-bottom substrates infers structural variables, and patterns of temporal distribution were basically influenced by parameters those indicating pollution and the SACW (South Atlantic Central Water) intrusion, as well as ecological attributes among species, such as: predation, competition. The Ervilia concentrica and Cypridinidae could be used as indicators for anthropic and natural impacts in the Guanabara Bay for the Entrance sector, while Cyprideis salebrosa and Cyprideis sp. for the Intermediary sector and Heleobia australis for the Inner sector.
Challenges and Opportunities for the Veterinary Pathologist in Biomedical Research

Animal models have critical roles in biomedical research in promoting understanding of human disease and facilitating development of new therapies and diagnostic techniques to improve human and animal health. In the study of myriad human conditions, each model requires in-depth characterization of its assets and limitations in order for it to be used to greatest advantage. Veterinary pathology expertise is critical in understanding the relevance and translational validity of animal models to conditions under study, assessing morbidity and mortality, and validating outcomes as relevant or not to the study interventions. Clear communication with investigators and education of research personnel on the use and interpretation of pathology endpoints in animal models are critical to the success of any research program. The veterinary pathologist is underutilized in biomedical research due to many factors including misconceptions about high fiscal costs, lack of perceived value, limited recognition of their expertise, and the generally low number of veterinary pathologists currently employed in biomedical research. As members of the multidisciplinary research team, veterinary pathologists have an important role to educate scientists, ensure accurate interpretation of pathology data, maximize rigor, and ensure reproducibility to provide the most reliable data for animal models in biomedical research.
Robots as intelligent assistants to face COVID-19 pandemic

Abstract Motivation The epidemic at the beginning of this year, due to a new virus in the coronavirus family, is causing many deaths and is bringing the world economy to its knees. Moreover, situations of this kind are historically cyclical. The symptoms and treatment of infected patients are, for better or worse even for new viruses, always the same: more or less severe flu symptoms, isolation and full hygiene. By now man has learned how to manage epidemic situations, but deaths and negative effects continue to occur. What about technology? What effect has the actual technological progress we have achieved? In this review, we wonder about the role of robotics in the fight against COVID. It presents the analysis of scientific articles, industrial initiatives and project calls for applications from March to now highlighting how much robotics was ready to face this situation, what is expected from robots and what remains to do. Results The analysis was made by focusing on what research groups offer as a means of support for therapies and prevention actions. We then reported some remarks on what we think is the state of maturity of robotics in dealing with situations like COVID-19.
Changes in endothelial glycocalyx layer protective ability after inflammatory stimulus.

Leukocyte adhesion to the endothelium is an important early step in the initiation and progression of sepsis. The endothelial glycocalyx layer (EGL) has been implicated in neutrophil adhesion and barrier dysfunction, but studies in this area are few. In this report we examine the hypothesis that damage to the structure of the EGL caused by inflammation leads to increased leukocyte adhesion and endothelial barrier dysfunction. We used human umbilical vein endothelial cells (HUVECs) enzymatically treated to remove the EGL components hyaluronic acid (HA) and heparan sulfate (HS) as a model for EGL damage. Using atomic force microscopy, we show reductions in EGL thickness after removal of either HA or HS individually, but the largest decrease, comparable to TNF-a treatment, was observed when both HA and HS were removed. Interestingly, removal of HS or HA individually did not affect neutrophil adhesion significantly, but removal of both constituents resulted in increased neutrophil adhesion. To test EGL contributions to endothelial barrier properties, we measured trans-endothelial electrical resistance (TEER) and diffusion of fluorescently labeled dextran (10 kDa MW) across the monolayer. Removal of EGL components decreased TEER, but had an insignificant effect on dextran diffusion rates. The reduction in TEER suggests that disruption of the EGL may predispose endothelial cells to increased rates of fluid leakage. These data support the view that damage to the EGL during inflammation has significant effects on the accessibility of adhesion molecules, likely facilitates leukocyte adhesion, and may also contribute to increased rates of fluid transport into tissues.
Water and lipid suppression techniques for advanced 1H MRS and MRSI of the human brain: Experts' consensus recommendations

The neurochemical information provided by proton magnetic resonance spectroscopy (MRS) or MR spectroscopic imaging (MRSI) can be severely compromised if strong signals originating from brain water and extracranial lipids are not properly suppressed. The authors of this paper present an overview of advanced water/lipid‐suppression techniques and describe their advantages and disadvantages. Moreover, they provide recommendations for choosing the most appropriate techniques for proper use. Methods of water signal handling are primarily focused on the VAPOR technique and on MRS without water suppression (metabolite cycling). The section on lipid‐suppression methods in MRSI is divided into three parts. First, lipid‐suppression techniques that can be implemented on most clinical MR scanners (volume preselection, outer‐volume suppression, selective lipid suppression) are described. Second, lipid‐suppression techniques utilizing the combination of k‐space filtering, high spatial resolutions and lipid regularization are presented. Finally, three promising new lipid‐suppression techniques, which require special hardware (a multi‐channel transmit system for dynamic B1+ shimming, a dedicated second‐order gradient system or an outer volume crusher coil) are introduced.
Pathogenesis of Thai duck Tembusu virus in BALB/c mice: descending infection and neuroinvasive virulence.

Duck Tembusu virus (DTMUV) is an emerging flavivirus that causes systemic disease in an avian host. The predominant cluster of DTMUV circulating in Thailand was recently classified as cluster 2.1. The pathogenesis of this virus has been extensively studied in avian hosts but not in mammalian hosts. Six-week-old BALB/c mice were intracerebrally or subcutaneously inoculated with Thai DTMUV to examine clinical signs, pathological changes, viral load, and virus distribution. Results demonstrated that the virus caused disease in BALB/c mice by the intracerebral inoculation route. Infected mice demonstrated both systemic and neurological symptoms. Pathological changes and virus distribution were observed in all tested organs. Viral load in the brain was significantly higher than in other organs (p<0.05), and the virus caused acute death in BALB/c mice. The virus was disseminated in all parts of the body, but no virus shedding was recorded in saliva and feces. Findings highlighted the potential of Thai DTMUV to transmit disease in mammalian hosts.
Wavelength stabilized ns-MOPA diode laser system with 16 W peak power and a spectral line width below 10 pm

A master oscillator power amplifier system for the generation of ns-pulses with high peak power, stabilized wavelength and narrow spectral line width will be presented. The master oscillator is a distributed feedback (DFB) ridge waveguide (RW) laser. The tapered amplifier consists of three RW sections and one flared gain-guided section. The DFB laser is operated in continuous wave mode and emits at 1064 nm with a spectral line width below 10 pm. One RW section of the amplifier acts as an optical gate for pulse selection. The tapered section amplifies the generated optical pulse. By adjusting the delay time between the current pulses injected into the picker and into the tapered section, respectively, the power of the amplified spontaneous emission was reduced below 1% of the average laser power. For an optical pulse length of 2 ns, a peak power of 16 W was obtained. A side mode suppression ratio better than 46 dB was observed.
Impact of Serum Uric Acid Lowering and Contemporary Uric Acid-Lowering Therapies on Cardiovascular Outcomes: A Systematic Review and Meta-Analysis

Objective: This study aimed to evaluate the potential association between uric acid (UA) lowering and cardiovascular risk reduction among UA-lowering therapies in adults. Methods: A systematic search for randomized controlled trials (RCTs) was conducted according to the protocol pre-registered in PROSPERO (No. CRD42020199259). We search for RCTs in PubMed, Embase, Web of Science, the Cochrane Library, and ClinicalTrials.gov up to July 1, 2020. A meta-analysis was performed using a fixed- or random-effects model. Results: In total, 30 studies involving 18,585 hyperuricaemic patients were included. Xanthine oxidase inhibitor (XOI) therapy produced a 6.0% reduction in relative risk (RR) for major adverse cardiovascular events (MACEs). The use of febuxostat was associated with a higher risk of cardiovascular events (CVEs) (RR: 1.09, 95% CI 0.998–1.19, I2 = 0.0%), but the difference was not statistically significant. Allopurinol treatment was associated with a lower CVE risk (RR: 0.61, 95% CI 0.46–0.80, I2 = 21.0%). Among the UA-lowering therapies, the drug treatments were associated with all-cause mortality (RR: 1.20, 95% CI 1.02–1.41, I2 = 0.0%). The subgroup with a UA endpoint <7 mg/dl was not associated with a higher CVE risk (RR: 0.57, 95% CI 0.35–0.92, I2 = 0.0%), and in the subgroup with a UA endpoint <5 mg/dl group, a lower risk of CVEs was not observed (RR: 0.99, 95% CI 0.69–1.44, I2 = 0.0%). Conclusions: UA reduction caused by XOIs reduced the incidence of MACEs. UA-lowering medicines were associated with changes in all-cause mortality but not cardiovascular outcomes. The lower UA endpoint was not associated with reduced cardiovascular risk.
Within-person associations among self-perceptions of memory, depressive symptoms, and activity participation in older adults.

BACKGROUND AND OBJECTIVES Self-perceptions of memory problems may impact older adults' mood as well as their activity participation, thereby negatively affecting health and well-being. We examined within-person associations among self-reported memory, depressive symptoms, as well as physical, social, and cognitive activity participation in older adults without cognitive impairment. RESEARCH DESIGN AND METHODS Samples were drawn from the Einstein Aging Study (EAS), National Health and Aging Trends Study (NHATS), Rush Memory and Aging Project (MAP), and Minority Aging Research Study (MARS), with over 8,000 participants (65+ years) included across datasets. In a series of coordinated analyses, multilevel structural equation modeling was used to examine within-person relationships over periods of up to 20 years. RESULTS Across EAS, NHATS, and MAP/MARS samples, we found that older adults' self-perceptions of memory did not directly co-vary with activity participation over time. However, we did find an indirect association in NHATS such that within-person changes in depressive symptoms were associated with changes in self-reported memory, and these contributed to lower physical as well as social activity participation. DISCUSSION AND IMPLICATIONS Older adults' activity participation is important for health, but maximizing engagement requires understanding potentially impeding factors. We found some evidence that as self-perceptions of memory change over time, associated depressive symptoms may contribute to lower activity participation. Inconsistent findings across data sets, however, suggest future research is needed to understand individual characteristics that may influence these relationships.
The Effect of Drying Technique on Tablets Formed from Extrusion-spheronization Granules

Abstract The impact of granule drying technique (oven and freeze) on tablet strength and dissolution characteristics was investigated for a range of propyl gallate (PG)/microcrystalline cellulose (MCC)/water granules generated via extrusion-spheronization. The tablet compaction data indicated that the granule yield point (GYP) was significantly lower for the freeze-dried granular material. As a consequence, for tablets compacted to the same final applied stress, the tablet surface was visibly smoother than that of the oven-dried counterparts. Granules with a lower GYP produced tablets of increased strength. Dissolution profiles were similar for both the oven- and freeze-dried samples with the exception of one formulation, where the freeze-dried material displayed a maximum dissolution rate nearly two-fold that of the oven-dried analogue. The degree of tablet break-up during dissolution dominated the mass transfer of PG.
Interdomain Flexibility of Chikungunya Virus nsP2 Helicase-Protease Differentially Influences Viral RNA Replication and Infectivity

CHIKV nsP2 plays multiple roles in viral RNA replication and virus-host interactions. The helicase and protease regions of nsP2 are connected through a short linker. ABSTRACT Chikungunya virus (CHIKV) is a mosquito-borne alphavirus responsible for chikungunya fever. Nonstructural protein 2 (nsP2), a multifunctional protein essential for viral replication, has an N-terminal helicase region (nsP2h), which has both nucleotide triphosphatase and RNA triphosphatase activities, as well as a C-terminal cysteine protease region (nsP2p), which is responsible for nonstructural polyprotein processing. The two functional units are connected through a linker of 14 residues. Although crystal structures of the helicase and protease regions of CHIKV nsP2 have been solved separately, the conformational arrangement of the full-length nsP2 and the biological role of the linker remain elusive. Using the small-angle X-ray scattering (SAXS) method, we demonstrated that the full-length nsP2 is elongated and partially folded in solution. The reconstructed model of the structure of nsP2 contains a flexible interdomain linker, and there is no direct interaction between the two structured regions. To examine the function of the interdomain linker, we constructed and characterized a set of CHIKV mutants. The deletion of three or five amino acid residues in the linker region resulted in a modest defect in viral RNA replication and transcription but completely abolished viral infectivity. In contrast, increasing the flexibility of nsP2 by lengthening the interdomain linker increased both genomic RNA replication and viral infectivity. The enzymatic activities of the corresponding mutant proteins were largely unaffected. This work suggests that increasing the interdomain flexibility of nsP2 could facilitate the assembly of the replication complex (RC) with increased efficiency and promote virus production. IMPORTANCE CHIKV nsP2 plays multiple roles in viral RNA replication and virus-host interactions. The helicase and protease regions of nsP2 are connected through a short linker. Here, we determined that the conformation of full-length CHIKV nsP2 is elongated and that the protein is flexible in solution. We also highlight the importance of the flexibility of the interdomain of nsP2 on viral RNA synthesis and infectivity. CHIKV mutants harboring shortened linkers fail to produce infectious virus particles despite showing only relatively mild defects in genomic and subgenomic RNA synthesis. Mutations increasing the length of the interdomain linker have only mild and generally beneficial impacts on virus replication. Thus, our findings link interdomain flexibility with the regulation of viral RNA replication and infectivity of the viral genome.
Mass Spectrometric Imaging of Plasma Membrane Lipid Alteration Correlated with Amperometrically Measured Activity-Dependent Plasticity in Exocytosis

The mechanism of synaptic plasticity and its link to memory formation are of interest, yet relatively obscure, especially the initial chemical change in the cell membrane following transmitter release. To understand the chemical mechanism of plasticity, we studied how repetitive stimuli regulate certain membrane lipid species to enhance exocytotic release using mass spectrometric imaging. We found that increasing high-curvature lipid species and decreasing low-curvature lipids in the cell membrane favor the formation of a longer-lasting exocytotic fusion pore, resulting in higher release fraction for individual exocytotic events. The lipid changes observed following repetitive stimuli are similar to those after exposure to the cognitive enhancing drug, methylphenidate, examined in a previous study, and offer an interesting point of view regarding the link between plasticity and memory and cognition.