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A difusão de pacotes tecnológicos que preconizam o uso de altas dosagens de adubos químicos e o controle de pragas e doenças, como métodos para manter o potencial produtivo das lavouras, obriga o produtor a utilizar aplicações sistemáticas de fertilizantes inorgânicos e pesticidas, o que vem afetando a sustentabilidade do agroecossistema cafeeiro, gerando uma total dependência de insumos industrializados. O objetivo deste estudo foi relacionar as mudanças nas características químicas, físicas e microbiológicas de um Latossolo Vermelho distrófico (LVd), da região de Santo Antônio do Amparo (MG), sob agroecossistemas de produção de "café orgânico", "em conversão" e "convencional", em relação a um fragmento de mata nativa. Em duas fazendas sob influência de condições similares de clima e relevo, apresentando o mesmo cultivar (Acaiá IAC474-19) e idade da lavoura (cinco anos), foi realizado um levantamento de dados por um período de um ano. O solo foi amostrado na profundidade de 0-20 cm, em duas épocas (julho/1999 e dezembro/1999). A análise de componentes principais permitiu uma visualização conjunta das características que mais influíram no comportamento do solo dos diferentes sistemas estudados. De modo geral, as formas de manejo para produção de café orgânico, em conversão e convencional, proporcionaram aumentos na fertilidade do solo, quando comparados com a condição do solo do fragmento de mata nativa. No agroecossistema de produção de café orgânico, foram obtidas maiores alterações das características químicas em relação ao convencional; houve incrementos no pH e nos valores de Ca, Mg, K, P, Zn, B, CTC do solo, soma de bases, saturação por bases e diminuição do Al trocável.

Metabolic syndrome (MSy) is a risk factor for cardiovascular disease. The decrease in vagal activity has been related to the mechanism of MSy development. Recently, it has been proposed that the WBV exercise, as well as osteopathic manipulative treatment (OMT) stimulate cardiac autonomic modulation. The aim of this study is to evaluate the acute effects of whole body-vibration (WBV) exercise and OMT on heart rate variability (HRV) in individuals with MSy. Cross-sectional, randomized, cross-over study (one-week wash-out between interventions) and blinding analysis. Individuals with MSy will be randomized into 5 groups: 1) whole body-vibration exercise group (WBVG), 2) osteopathic manipulative treatment group (OMTG), 3) WBVG + OMTG, 4) OMTG + WBVG, 5) control group (CG). OMT will consist of suboccipital decompression technique, myofascial relaxation on cervical and diaphragm muscles. The HRV measurement will be done with the individual at rest, during the 2-min step test (2MST) and during interventions. After the treatment, the measurements will be repeated. The modulation of ANS is important in the management of MSy individuals. The investigation of intervention modalities to improve this modulation is necessary and it is expected that this protocol can promote this modulation and improve the HRV. [ABSTRACT FROM AUTHOR]

Concerns about the increasing impact of severe COVID-19 in younger individuals in Brazil came after a recent synchronised country-wide wave of cases in Brazil. This communication analyses how hospitalisations due to COVID-19 changed in the age groups 18–49 years and ≥70 years. Longitudinal study based on secondary data. Data from SIVEP-Gripe, a public and open-access database of Severe Acute Respiratory Illness records (including COVID-19 notifications), were used in this study. Statistical control charts examined changes in the magnitude and variation of younger (18–49 years) and older (≥70 years) adults who were hospitalised between 15th March 2020 and 19th June 2021. During the few first weeks of the pandemic in Brazil, the number of COVID-19 hospitalisations increased in older adults but decreased in younger adults. Subsequently, hospitalisations reached statistical control zones in epidemiological weeks (EW) 19–48 of 2020 (EW 19-48/2020) and EW 03-05/2021 (18–49 y, mean = 26.1%; ≥70 y, mean = 32.8%). Between EW 49/2020 and EW 02/2021, the number of hospitalisations of younger adults dropped to levels below the lower control limit. In contrast, the number of hospitalisations of older adults surpassed the upper limit of the corresponding statistical control zones. However, from EW 06/2021, numbers of hospitalisations changed from statistical control zones, with hospitalisations of younger adults increasing and reaching 44.9% in EW 24/2021 and hospitalisations of older adults decreasing until EW 19/2021 (14.1%) and reaching 17.3% in EW 24/2021. An increasing number of COVID-19 hospitalisations were observed in younger adults from EW 06/2021. This could be a result of the successful vaccination programme in older adults, who were initially prioritised, and possibly an increased exposure to highly transmissible variants of COVID-19 in younger adults who had to go to work in the absence of social protection (i.e. government financial support). Potential consequences of COVID-19 hospitalisations in younger adults could include a reduced life expectancy of the population and an increased number of people unable to perform daily activities due to post-COVID-19 conditions. [ABSTRACT FROM AUTHOR]

Even though the impact of COVID-19 in metropolitan areas has been extensively studied, the geographic spread to smaller cities is also of great concern. We conducted an ecological study aimed at identifying predictors of early introduction, incidence rates of COVID-19 and mortality (up to 8 May 2020) among 604 municipalities in inner São Paulo State, Brazil. Socio-demographic indexes, road distance to the state capital and a classification of regional relevance were included in predictive models for time to COVID-19 introduction (Cox regression), incidence and mortality rates (zero-inflated binomial negative regression). In multivariable analyses, greater demographic density and higher classification of regional relevance were associated with both early introduction and increased rates of COVID-19 incidence and mortality. Other predictive factors varied, but distance from the State Capital (São Paulo City) was negatively associated with time-to-introduction and with incidence rates of COVID-19. Our results reinforce the hypothesis of two patterns of geographical spread of SARS-Cov-2 infection: one that is spatial (from the metropolitan area into the inner state) and another which is hierarchical (from urban centres of regional relevance to smaller and less connected municipalities). Those findings may apply to other settings, especially in developing and highly heterogeneous countries, and point to a potential benefit from strengthening non-pharmaceutical control strategies in areas of greater risk. [ABSTRACT FROM AUTHOR]

FexCu100-x metastable alloys were prepared by pulsed electrodeposition for 550) are reminiscent of those observed in Fe–Cu alloys prepared by other methods. The Curie temperature decreases regularly with decreasing x. In the Fe-poor alloys (x≤30), the observed properties indicate that Fe-rich clusters form within a Cu-rich matrix. In the x=10 alloy, the Fe clusters are found to be superparamagnetic at room temperature, but a superferromagnetic order develops below a critical temperature of about 120 K. It is suggested that the intercluster coupling is mediated by Ruderman–Kittel–Kasuya–Yosida interactions which are predominantly positive due to the very short intercluster distances. [ABSTRACT FROM AUTHOR]

We present an investigation of the properties of the extended Ly α halo and the large-scale |${\rm H\, {\small I}}$| absorbing structures associated with five high-redshift radio galaxies at |$z$| > 2, using the Goodman long-slit spectrograph on the SOAR telescope, with the slit placed at large angles (>45°) to the radio axis, to study regions that are unlikely to be illuminated by the active nucleus. Spatially extended Ly α emission is detected with large line widths [full width at half-maximum (FWHM) = 1000–2500 km s−1], which although impacted by resonant scattering, is suggestive of turbulent motion. We find a correlation between higher blueshifts and higher FWHM, which is an indication that radial motion dominates the bulk gas dynamics perpendicular to the radio axis, although we are unable to distinguish between outflow and infall scenarios due to the resonant nature of the Ly α line. Extended, blueshifted Ly α absorption is detected in the direction perpendicular to the radio axis in three radio galaxies with minimum spatial extents ranging from ≳27 to ≳35 kpc, supporting the idea that the absorbing structure covers the entire Ly α halo, consistent with being part of a giant, expanding shell of gas enveloping the galaxy and its (detected) gaseous halo. [ABSTRACT FROM AUTHOR]

Deals with a study which used the Rutherford backscattering technique to determine the range parameters of Bi ions implanted into AZ111 photoresist film at energies from ten to 400 keV. Experimental procedure and data analysis; Results and discussion; Conclusions.

A female specimen of Phaeotabanus litigiosus (Diptera: Tabanidae) collected on Marambaia Island was found with a tumor in the abdominal integument. Histopathological examination revealed an epithelial dysplasia with anisokariosis and hyperchromasia. This is the first record of a neoplasm found in tabanid collected from natural environment. [ABSTRACT FROM AUTHOR]

Zooarchaeological collections from shell mounds in Rio de Janeiro (2,470-4,632 cal BP) contain a high prevalence of swollen fish bones belonging to the Atlantic spadefish ( Chaetodipterus faber), crevalle jack ( Caranx hippos) and fat snook ( Centropomus parallelus). Given the lack of knowledge of the bone degenerative process in senile fishes, this study analysed hyperostotic bone in zooarchaeological and modern specimens to obtain high-resolution morphology and microstructure reconstruction. We used micro CT as well as X-ray diffraction to characterize the crystallographic changes associated with fish senility. Our results showed that trabecular microstructures in hyperostotic bones were consistent with estimated values of the per cent bone volume-to-total volume ratio ( BV/ TV) and were greater than 60% in cortical bone. Hyperostotic bones indicated a high radiograph density, and X-ray diffractograms showed a decrease in hydroxyapatite [Ca10( PO4)6( OH)2] and calcite (Ca CO3) neocrystallization. These crystalline and density changes revealed an advanced stage of fish senile and indicate the vulnerability of ageing fish populations. [ABSTRACT FROM AUTHOR]

Biodiversity is commonly referred to as species diversity but in forest ecosystems variability in structural and functional characteristics can also be treated as measures of biodiversity. Small unmanned aerial vehicles (UAVs) provide a means for characterizing forest ecosystem with high spatial resolution, permitting measuring physical characteristics of a forest ecosystem from a viewpoint of biodiversity. The objective of this study is to examine the applicability of photogrammetric point clouds and hyperspectral imaging acquired with a small UAV helicopter in mapping biodiversity indicators, such as structural complexity as well as the amount of deciduous and dead trees at plot level in southern boreal forests. Standard deviation of tree heights within a sample plot, used as a proxy for structural complexity, was the most accurately derived biodiversity indicator resulting in a mean error of 0.5 m, with a standard deviation of 0.9 m. The volume predictions for deciduous and dead trees were underestimated by 32.4 m3/ha and 1.7 m3/ha, respectively, with standard deviation of 50.2 m3/ha for deciduous and 3.2 m3/ha for dead trees. The spectral features describing brightness (i.e. higher reflectance values) were prevailing in feature selection but several wavelengths were represented. Thus, it can be concluded that structural complexity can be predicted reliably but at the same time can be expected to be underestimated with photogrammetric point clouds obtained with a small UAV. Additionally, plot-level volume of dead trees can be predicted with small mean error whereas identifying deciduous species was more challenging at plot level. [ABSTRACT FROM AUTHOR]

This work focused on fracture toughness studies of WC–10 wt% Co hardmetal fabricated through the high pressure/high-temperature technique. A powder mixture of WC–10 wt% Co was sintered at 1500–1900°C under a pressure of 7.7 GPa for 2 and 3 min. Vickers hardness test at two different loads of 15 and 30 kgf was done and fracture toughness of the sintered bodies was measured using the indentation method to obtain the effect of sintering parameters. Structural analyses were also performed via X-ray diffraction to investigate structure-related properties. Full density was achieved for high sintering temperature along with abnormal grain growth that reduced hardness. High hardness was observed ranging from 1200 to 1670 HV and fracture toughness increased with increasing sintering temperature up to the highest value of 17.85 MPa/m1/2. [ABSTRACT FROM AUTHOR]

Presents information on a study that compared the profiles of bismuth, xenon, tin, krypton, gallium, iron, potassium, argon, phosphorus, sodium and fluorine implanted into the AZ111 photoresist with theoretical predictions. Experimental procedure; Results and discussion.

Presents information on a study which determined the depth distribution of ion-implanted [sup10]boron in AZ111 photoresist in the 30-150 kiloelectrovolts energy range. Aspects of ion-implanted and irradiated polymers; Experimental procedure; Results and discussion; Conclusions.

Copyright of Caderno Brasileiro de Ensino de Física is the property of Caderno Brasileiro de Ensino de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During oil refining, equipments are constantly exposed to the action of compounds such as salts, leading corrosion problems and to decrease in equipment service life. Soon, the growing search for productivity increasingly demand more strategies to monitor the processes and minimize costs. This article contributes to the methodology development to study the chlorides released during the oil distillation, in a similar process that occurs in refineries, enabling predict and minimize damage. Oils were evaluated with respect to chloride release during each stage of oil heating. Salinity mass balance were obtained as well as their respective chloride release percentage to each oil. [ABSTRACT FROM AUTHOR]

Ineffective solid waste management constitutes a major environmental problem in the major cities in Nigeria. This is as a result of lacking adequate plans in education and enforcement on environmental discipline, basic infrastructures for an efficient and sustainable management of municipal solid waste which poses health risk to the Nigerian people. In bid to achieve a sustainable and aesthetic environment, the study aims to promote the optimization of geospatial technology as a supportive tool in municipal solid waste management and sanitation monitoring in Nigeria using a conceptualized framework. The study also identifies the stakeholders in environmental management and sanitation to collaborate with the National Space Research and Development Agency (NARSDA) towards attaining a sustainable solid waste management program in Nigeria. The approach employed the use of Geographic information systems (GIS) and Remote sensing (RS), building a geodatabase in municipal solid waste management as baseline data for the nation, Radio frequency Identification (RFID), GPS and GPRS/GSM and other ancillary data in solid waste management and monitoring. The incorporation of geospatial technology using the Nigerian earth observation satellites (NigeriaSat-2 and NigeriaSat-X) and integrated communication technologies in municipal solid waste management and monitoring in Nigeria will enhance budget planning for contingency plan to assist decision makers build a sustainable platform in the solid waste sector. The study promotes synergy, commitment and information sharing among stakeholders in municipal solid waste (MSW) management in Nigeria. [ABSTRACT FROM AUTHOR]

Background and purpose Machado−Joseph disease ( MJD/ SCA3) is the most frequent spinocerebellar ataxia, characterized by brainstem, basal ganglia and cerebellar damage. Few magnetic resonance imaging based studies have investigated damage in the cerebral cortex. The objective was to determine whether patients with MJD/ SCA3 have cerebral cortex atrophy, to identify regions more susceptible to damage and to look for the clinical and neuropsychological correlates of such lesions. Methods Forty-nine patients with MJD/ SCA3 (mean age 47.7 ± 13.0 years, 27 men) and 49 matched healthy controls were enrolled. All subjects underwent magnetic resonance imaging scans in a 3 T device, and three-dimensional T1 images were used for volumetric analyses. Measurement of cortical thickness and volume was performed using the FreeSurfer software. Groups were compared using ancova with age, gender and estimated intracranial volume as covariates, and a general linear model was used to assess correlations between atrophy and clinical variables. Results Mean CAG expansion, Scale for Assessment and Rating of Ataxia ( SARA) score and age at onset were 72.1 ± 4.2, 14.7 ± 7.3 and 37.5 ± 12.5 years, respectively. The main findings were (i) bilateral paracentral cortex atrophy, as well as the caudal middle frontal gyrus, superior and transverse temporal gyri, and lateral occipital cortex in the left hemisphere and supramarginal gyrus in the right hemisphere; (ii) volumetric reduction of basal ganglia and hippocampi; (iii) a significant correlation between SARA and brainstem and precentral gyrus atrophy. Furthermore, some of the affected cortical regions showed significant correlations with neuropsychological data. Conclusions Patients with MJD/ SCA3 have widespread cortical and subcortical atrophy. These structural findings correlate with clinical manifestations of the disease, which support the concept that cognitive/motor impairment and cerebral damage are related in disease. [ABSTRACT FROM AUTHOR]

Copyright of Motricidade is the property of Silabas Didaticas LDA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Motricidade is the property of Silabas Didaticas LDA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report on the dynamical behavior of defects of strength s = ±1/2 in a lyotropic liquid crystal during the annihilation process. By following their positions using time-resolved polarizing microscopy technique, we present statistically significant evidence that the relative velocity between defect pairs is Gaussian distributed, antipersistent, and long-range correlated. We further show that simulations of the Lebwohl-Lasher model reproduce quite well our experimental findings. [ABSTRACT FROM AUTHOR]

Spade methods to visually evaluate soil structural quality (Sq) are simple, quick, cheap and can be used by farmers, gardeners, consultants and the scientific community. However, European and Brazilian users of one such method, viz. visual evaluation of soil structure (VESS) which is a development of the Peerlkamp test, have been concerned about its subjectivity. The method of soil slice break-up and operator influence on scores have been questioned. Thus, our aim was to make soil scoring by the VESS technique more objective and thus to revise the scoring guide. We compared scoring with normal breaking up of the soil slice by hand with scoring after breaking up the slice by dropping (drop shatter) to make the soil break-up more operator independent. After slice break-up, aggregates were split by hand and their internal porosity was evaluated to develop the use of visible porosity as an aid to scoring. This proved inconclusive on its own, so a method of reducing larger aggregates to 1.5-2.0 cm core fragments and describing their shape and porosity was developed to score soil Sq. Breaking up a spadeful of soil by hand or by dropping resulted in the same Sq score. The method of reducing aggregates and evaluation of their shape improved VESS, particularly in the middle range of soil quality and the revised chart is shown. VESS was sensitive to changes in Sq in layers within the profile and its use for diagnosing Sq in different layers allows targeted soil improvement by tillage. [ABSTRACT FROM AUTHOR]

Nanostrucured europium oxide and hydroxide films were obtained by pulsed Nd:YAG (532 nm) laser ablation of a europium metallic target, in the presence of a 1 mbar helium buffer atmosphere. Both the produced film and the ambient plasma were characterized. The plasma was monitored by an electrostatic probe, for plume expansion in vacuum or in the presence of the buffer atmosphere. The time evolution of the ion saturation current was obtained for several probe to substrate distances. The results show the splitting of the plume into two velocity groups, being the lower velocity profile associated with metal cluster formation within the plume. The films were obtained in the presence of helium atmosphere, for several target-to-substrate distances. They were analyzed by Rutherford backscattering spectrometry, x-ray diffraction, and atomic force microscopy, for as-deposited and 600 °C treated-in-air samples. The results show that the as-deposited samples are amorphous and have chemical composition compatible with europium hydroxide. The thermally treated samples show x-ray diffraction peaks of Eu2O3, with chemical composition showing excess oxygen. Film nanostructuring was shown to be strongly correlated with cluster formation, as shown by velocity splitting in probe current versus time plots. [ABSTRACT FROM AUTHOR]

In recent years, the Lyman- α forest in quasar spectra has been used, together with N-body simulations, to determine the underlying matter distribution in the intergalactic medium (IGM). One of the key parameters to be known in order to compare observations and numerical simulations is the mean HI absorption in the IGM. To derive the latter, one has first to fit the quasar continuum. We have observed 20 high redshift and highly luminous QSOs ( m ≤ 17.5 and 2.40 ≤ z ≤ 3.91) at intermediate spectral resolution, with either EMMI (ESO Multi-Mode Instrument) on the ESO-NTT telescope or CARELEC at the OHP (Observatoire de Haute-Provence), and applied different methods of determining the QSO continuum to this QSO sample. We have measured the amount of absorption, known as the flux decrement, DA, in the Lyman- α forest for these different methods and compared the results. In addition, we have compared DA values measured along the same lines of sight observed at high and intermediate spectral resolutions. We discuss the systematics resulting from the use of automatic continuum fitting methods. [ABSTRACT FROM AUTHOR]

The phenomenon of frequency upconversion (UC) is observed in Er3+:Yb3+:SrAl2O4 powders prepared by combustion synthesis. Strong UC emission at the green (bands peaked at 521, 538, 547, and 562 nm) and weak UC emission at the red (bands peaked at 659 and 682 nm) corresponding to 4f–4f transitions of Er3+ were observed when the samples were irradiated with near-infrared laser excitation at ∼980 nm. Saturation of UC emission is observed for concentrations of 1.5 wt.% of Er3+ and 1.5 wt.% of Yb3+. The green-to-red intensity ratio, on the other hand, increases linearly with Er3+ concentration (Er3+ concentration varying from 0.5 to 1.5 wt.%) while keeping Yb3+ concentration fixed (at 1.5 wt.%). The green UC decay time was measured and Er3+–Er3+ interaction was suggested as a possible mechanism to explain the luminescence quenching effect observed. [ABSTRACT FROM AUTHOR]

The phenomenon of frequency upconversion (UC) is observed in Er3+:Yb3+:SrAl2O4 powders prepared by combustion synthesis. Strong UC emission at the green (bands peaked at 521, 538, 547, and 562 nm) and weak UC emission at the red (bands peaked at 659 and 682 nm) corresponding to 4f–4f transitions of Er3+ were observed when the samples were irradiated with near-infrared laser excitation at ∼980 nm. Saturation of UC emission is observed for concentrations of 1.5 wt.% of Er3+ and 1.5 wt.% of Yb3+. The green-to-red intensity ratio, on the other hand, increases linearly with Er3+ concentration (Er3+ concentration varying from 0.5 to 1.5 wt.%) while keeping Yb3+ concentration fixed (at 1.5 wt.%). The green UC decay time was measured and Er3+–Er3+ interaction was suggested as a possible mechanism to explain the luminescence quenching effect observed. [ABSTRACT FROM AUTHOR]