.
The present status of fusion reactions involving light (
A
< 20) radioactive projectiles at energies around the Coulomb barrier (
E
< 10 MeV per nucleon) is reviewed, emphasizing measurements made ...within the last decade. Data on elastic scattering (providing total reaction cross section information) and breakup channels for the involved systems, demonstrating the relationship between these and the fusion channel, are also reviewed. Similarities and differences in the behavior of fusion and total reaction cross section data concerning halo nuclei, weakly-bound but less exotic projectiles, and strongly-bound systems are discussed. One difference in the behavior of fusion excitation functions near the Coulomb barrier seems to emerge between neutron-halo and proton-halo systems. The role of charge has been investigated by comparing the fusion excitation functions, properly scaled, for different neutron- and proton-rich systems. Possible physical explanations for the observed differences are also reviewed.
In this review paper we present a detailed account of the extraction and the calculation of the total reaction cross section of strongly bound and weakly bound, stable and unstable, exotic, nuclei. ...We discuss the optical model and the more general coupled channels model of direct reactions, and how from fits to the data on elastic scattering supplies the elastic element of (partial wave) S-matrix and correspondingly the differential cross section and the total reaction cross section. The effect of long-range absorption due to the coupling to excited states in the target and to the breakup continuum in the projectile is also discussed. The semiclassical method is then analyzed and the Hill–Wheeler expression of the tunneling probability and the Wong formula for the fusion and the total reaction cross sections are discussed in details. The generalized optical theorem for charged particle scattering and the resulting sum-of differences method is then discussed. Also, the strong absorption model in its sharp cutoff form and its generalization, the smooth cutoff, is discussed. The so-called “quarter-point recipe” is discussed next, and the quarter-point angle is introduced as a simple and rapid mean to obtain the total reaction cross section. The last topic discussed is the reduction of the total reaction cross section that would allow a large body of data to sit on a single universal function. Such a universal function exists in the case of the fusion data, and the aim of this last topic of the review is to extend the fusion case to the total reaction, by adding the direct reaction contribution. Also discussed is the inclusive breakup cross section and how it can be used to extract the total reaction cross section of the interacting fragment with the target. This method is also known as the Surrogate method and represents a case of hybrid reactions. The sum of the integrated inclusive breakup cross section with the complete fusion cross section supplies the total fusion cross section. A review of the experimental methods and techniques used to measure elastic scattering and breakup reactions is also presented. Emphasis is given to recent experiments and new techniques developed to deal with reactions induced by unstable beams. We discuss also the experimental challenges in these measurements and highlight the new techniques being developed to optimize measurements with radioactive ion beams.
An optical model analysis of the available data for A = 8 (
8
He,
8
Li and
8
B) projectiles on different targets with light, medium and heavy mass has been performed. A systematic potential set based ...on a Woods–Saxon Potential shape was obtained. This potential describes the elastic scattering angular distributions quite well. A more physical model within the framework of a semi-microscopic approach, where the nuclear matter density distributions of the
8
B,
8
Li and
8
He projectiles have been calculated by using a microscopic self-consistent relativistic mean field (RMF) theory, was also considered. The agreement of the calculated angular distributions with the data was reasonable. An improvement of the agreement could be achieved by changing the imaginary diffuseness parameter, which is a sensitive parameter in these calculations.
Plant-galling insect interactions Cintra, Fernanda C. F.; de Araújo, Walter S.; Maia, Valéria C. ...
Ecology (Durham),
11/2020, Letnik:
101, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Recent decades have seen increased research interest in the processes and mechanisms related to insect gall richness and host plants. The data set provided here includes 968 records of interactions ...between galling insects and host plants for the Cerrado biome. The data set comprises 505 species of 222 genera and 67 families of host plants. The botanical families most represented in the data set are Asteraceae, Fabaceae, Myrtaceae, Malpighiaceae, and Melastomataceae, which account for ~48.5% of all records and 52% of the total number of species. The gall-inducing insects listed in the data set include 48 species of Cecidomyiidae and one species of Tephritidae. This data set is the first to compile inventories of plant-galling insect communities and information about the diversity and distribution of insect galls and their host plants in the Cerrado. The data set reveals knowledge gaps and opportunities for future research on patterns of diversity and distribution, and provides a basis for generating and testing new ecological hypotheses. Please cite this data paper when using the current data in publications and let us know how the data are used in the publications. There are no copyright restrictions.
Exercise training has an important role in the prevention and treatment of hypertension, but its effects on the early metabolic and hemodynamic abnormalities observed in normotensive offspring of ...hypertensive parents (FH+) have not been studied. We compared high-intensity interval (aerobic interval training, AIT) and moderate-intensity continuous exercise training (CMT) with regard to hemodynamic, metabolic and hormonal variables in FH+ subjects. Forty-four healthy FH+ women (25.0+/-4.4 years) randomized to control (ConFH+) or to a three times per week equal-volume AIT (80-90% of VO(2MAX)) or CMT (50-60% of VO(2MAX)) regimen, and 15 healthy women with normotensive parents (ConFH-; 25.3+/-3.1 years) had their hemodynamic, metabolic and hormonal variables analyzed at baseline and after 16 weeks of follow-up. Ambulatorial blood pressure (ABP), glucose and cholesterol levels were similar among all groups, but the FH+ groups showed higher insulin, insulin sensitivity, carotid-femoral pulse wave velocity (PWV), norepinephrine and endothelin-1 (ET-1) levels and lower nitrite/nitrate (NOx) levels than ConFH- subjects. AIT and CMT were equally effective in improving ABP (P<0.05), insulin and insulin sensitivity (P<0.001); however, AIT was superior in improving cardiorespiratory fitness (15 vs. 8%; P<0.05), PWV (P<0.01), and BP, norepinephrine, ET-1 and NOx response to exercise (P<0.05). Exercise intensity was an important factor in improving cardiorespiratory fitness and reversing hemodynamic, metabolic and hormonal alterations involved in the pathophysiology of hypertension. These findings may have important implications for the exercise training programs used for the prevention of inherited hypertensive disorder.
Aims
We evaluated the effect of
Azospirillum brasilense
strain HM053 inoculation on maize seeds, a spontaneous mutant that excrete ammonium and fix nitrogen constitutively.
Methods
Maize was grown ...with different nitrogen (urea) concentration and inoculated with
A. brasilense
Ab-V5 (Brazilian commercial strain) or HM053 strain in four field experiments, in three regions of Parana State, Southern Brazil. We evaluated yield components, nutrient content on leaves and grains and productivity during the crop cycle.
Results
Inoculation with
A. brasilense
strain Ab-V5 and HM053 associated with base fertilization (30 kg ha
−1
N) improved crop yield in all trials. Ab-V5 increased production between 2.2 to 10.4%, or 178.0 to 759.9 kg ha
−1
, respectively. HM053, by itself, increased production between 4.7 to 29%, or 460.5 to 1769.3 kg ha
−1
, respectively.
Conclusion
The new strain HM053 showed to be a great biofertilizer for maize seeds and a new alternative for a more sustainable agriculture.
Cognitive impairment is a critical aspect of our aging society. Yet, it receives inadequate intervention due to delayed or missed detection. Dual-task gait analysis is currently considered a solution ...to improve the early detection of cognitive impairment in clinical settings. Recently, our group proposed a new approach for the gait analysis resorting to inertial sensors placed on the shoes. This pilot study aimed to investigate the potential of this system to capture and differentiate gait performance in the presence of cognitive impairment based on single- and dual-task gait assessments.
We analyzed demographic and medical data, cognitive tests scores, physical tests scores, and gait metrics acquired from 29 older adults with mobility limitations. Gait metrics were extracted using the newly developed gait analysis approach and recorded in single- and dual-task conditions. Participants were stratified into two groups based on their Montreal Cognitive Assessment (MoCA) global cognitive scores. Statistical analysis was performed to assess differences between groups, discrimination ability, and association of gait metrics with cognitive performance.
The addition of the cognitive task influenced gait performance of both groups, but the effect was higher in the group with cognitive impairment. Multiple dual-task costs, dual-task variability, and dual-task asymmetry metrics presented significant differences between groups. Also, several of these metrics provided acceptable discrimination ability and had a significant association with MoCA scores. The dual-task effect on gait speed explained the highest percentage of the variance in MoCA scores. None of the single-task gait metrics presented significant differences between groups.
Our preliminary results show that the newly developed gait analysis solution based on foot-worn inertial sensors is a pertinent tool to evaluate gait metrics affected by the cognitive status of older adults relying on single- and dual-task gait assessments. Further evaluation with a larger and more diverse group is required to establish system feasibility and reliability in clinical practice.
ClinicalTrials.gov (identifier: NCT04587895).
Iron-doped bismuth sulphide (Bi
Fe
S₃) nanocrystals have been successfully synthesized in a glass matrix using the fusion method. Transmission electron microscopy images and energy dispersive ...spectroscopy data clearly show that nanocrystals are formed with an average diameter of 7-9 nm, depending on the thermic treatment time, and contain Fe in their chemical composition. Magnetic force microscopy measurements show magnetic phase contrast patterns, providing further evidence of Fe incorporation in the nanocrystal structure. The electron paramagnetic resonance spectra displayed Fe
typical characteristics, with spin of 5/2 in the 3d⁵ electronic state, thereby confirming the expected trivalent state of Fe ions in the Bi₂S₃ host structure. Results from the spin polarized density functional theory simulations, for the bulk Fe-doped Bi₂S₃ counterpart, corroborate the experimental fact that the volume of the unit cell decreases with Fe substitutionally doping at Bi1 and Bi2 sites. The Bader charge analysis indicated a pseudo valency charge of 1.322|
| on Fe
₁ and 1.306|
| on Fe
₂ ions, and a spin contribution for the magnetic moment of 5.0
per unit cell containing one Fe atom. Electronic band structures showed that the (indirect) band gap changes from 1.17 eV for Bi₂S₃ bulk to 0.71 eV (0.74 eV) for Bi₂S₃:Fe
(Bi₂S₃:Fe
). These results are compatible with the 3d⁵ high-spin state of Fe
, and are in agreement with the experimental results, within the density functional theory accuracy.
ABSTRACT Weeds have several mechanisms of dispersal and reproduction, resulting high spatial variability. The objective of this study was to assess the scale and spatial heterogeneity of weeds using ...multifractal analysis in a no-tillage system in the Pre-Amazon region. Sampling was conducted in a commercial soybean (Glycine max) production plot in the Mata Roma, Maranhão, Brazil, comprising 1,071 points marked on a 10 × 10 m grid. Data were analyzed using descriptive statistics and multifractal analysis through the box-counting method. Weeds showed varying degrees of multifractality, resulting in different scales and spatial heterogeneity in the study area. Euphorbia hirta and Turnera subulata exhibited asymmetry of branches to the left in the singularity spectrum, indicating dominance of high measurement values.
RESUMO As plantas-daninhas possuem diversos mecanismos de dispersão e reprodução descrevendo elevada variabilidade espacial. O objetivo deste estudo foi avaliar a heterogeneidade de escala e espacial de plantas-daninhas utilizando análise multifractal em sistema de semeadura direta na região Pré-Amazônia. A amostragem foi realizada em uma parcela de produção comercial cultivada com soja (Glycine max). Na área de estudo foram demarcados 1.071 pontos, em malha regular de 10 × 10 m, no município de Mata Roma (Maranhão, Brasil). Os dados foram analisados por meio da estatística descritiva e análise multifractal empregando o método box-counting. As plantas-daninhas apresentaram diferentes graus de multifractalidade, descrevendo maior ou menor heterogeneidade de escala e espacial na área de estudo. Euphorbia hirta e Turnera subulata apresentaram assimetria dos ramos do espectro de singularidade para a esquerda, indicando domínio de valores elevados de medidas.
The treatment of choice for chronic atrophic candidiasis (CAC), also known as denture stomatitis, is topical antifungal therapy. This study aimed to isolate, identify, and assess the antifungal ...susceptibility of Candida species from mucosal sites in denture wearers with a diagnosis of CAC and determine the prevalence of associated variables. The sample consisted of 44 patients wearing complete or partial dentures who had a clinical diagnosis of CAC. Using sterile cotton swabs, specimens were collected from the oral mucosa of all patients and grown at 30ºC for 48 h in CHROMagar Candida, as a means of isolating and screening the species. The complementary identification of the species was performed using the VITEK 2 automated system (BioMérieux), as well as the determination of their susceptibility to antifungal agents. Data were analyzed using the chi-square test. STATA 13.1 was used for statistical analysis (α = 5%). Of 44 patients with CAC, 33 (75%) had lesions classified as Newton type II. Yeasts were isolated in 38 cases. The most prevalent species was Candida albicans. None of the isolates were resistant to the antifungals tested. Our findings suggest that current indications for antifungal agents are appropriate. Also, antifungal susceptibility testing and proper fungal identification can help dentists to determine the optimal course of treatment for CAC.
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