The bioactivity of humic acids (HA) is mainly due to the presence of auxin analogs. In turn, nitric oxide (NO) production in plants affects root growth and may result from endogenous auxin production or the applicatio...The bioactivity of humic acids (HA) is mainly due to the presence of auxin analogs. In turn, nitric oxide (NO) production in plants affects root growth and may result from endogenous auxin production or the application of synthetic auxin analogs or HA. Nitric oxide signaling may be related to the bioactivity of the HA. Although the auxin, NO, and ROS-mediated activity of HA has been studied, no studies exist on their effects in Ocimum basilicum L., commonly known as basil. A study under controlled in vitro conditions was performed using hairy roots (hairy roots) of basil grown in medium with N-NO3- (0.5 or 5.0 mM) and subjected to treatments with HA (3 mMC·L-1) or sodium nitroprusside (SNP;100 μM), an NO donor, either without or with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO;200 μM), an NO scavenger. The addition of HA and SNP resulted in significant increases in the root growth, associated with increased NO and reactive oxygen species (ROS) contents. The application of the NO scavenger cPTIO with the SNP and HA decreased the effects of both substances on the root growth and endogenous levels of the NO and ROS. The increased root growth promoted by the NO donor (SNP) and HA was also associated with increased proton pump and catalase activity for both N-NO3- levels tested. The results showed that the effects of HA are dependent on NO and ROS, which act as messengers, inducing root growth.展开更多
The fodder radish is an important alternative late summer crop in central-western Brazil. The fodder radish has a short growing cycle, is highly productive and possesses qualities that enhance its cultivation potentia...The fodder radish is an important alternative late summer crop in central-western Brazil. The fodder radish has a short growing cycle, is highly productive and possesses qualities that enhance its cultivation potential as an alternative in Brazil’s Biodiesel Program. However, drift of herbicides, such as glyphosate, may hinder the development of fodder radishes. Studies of chlorophyll fluorescence can provide measurements that help assess the effect of herbicide, being good indicator of the damage to photosynthetic apparatus promoted by herbicide. This study was carried out to analyze the effects of glyphosate by measuring chlorophyll a fluorescence, cellular membrane stability and chloroplast pigment contents in fodder radish plants. This experiment used a randomized block design in which the treatments consisted of the following 6 different doses: control, 0, 150, 300, 450, 600, 750 and 900 g i.a. ha-1 of the recommended 480 g·L-1 dose of glyphosate acid equivalent. The plants were sprayed 30 days after emergence and were assessed every 48 hours. The characteristics evaluated, including chlorophyll a fluorescence, chloroplast pigments and the rate of electrolyte leakage, indicated that radish plants are sensitive to glyphosate because the treatments resulted in reduced levels of photosynthetic efficiency and increased damage to cellular membranes, which led to a reduction in the chloroplast pigment content.展开更多
The production of mushrooms enriched with essential elements, e.g. selenium, for human health is an interesting strategy to improve the functional foods supply. The selenium is an essential mineral and makes part of s...The production of mushrooms enriched with essential elements, e.g. selenium, for human health is an interesting strategy to improve the functional foods supply. The selenium is an essential mineral and makes part of structure of enzymes involved in the oxidative metabolism. However, the selenium effect on the activity of respiratory and lignocellulolytic enzymes has not been considered. The understanding of this effect is important to determine the selenium concentration that increases the mushroom productivity and the degradation rate of the substrate. In this study, it was observed reduction of the respiratory activity of Lentinula edodes (Berk.) Pegler, the shiitake mushroom, in function of the increasing of the sodium selenite concentration in the substrate (p < 0.05). Selenium did not inhibit the activity of the hydrolytic enzymes (cellulase and xylanase), but it increased the activity of the oxidative enzyme (laccase). Respiratory activity of L. edodes has a negative correlation with sodium selenite concentration added in substrate. Thus is important to define the ideal dose of selenium to be added to the substrate for increasing lignocellulosic residues degradation and, consequently, guarantee a higher production of Se-enriched mushrooms.展开更多
Short-wavelength near infrared spectroscopy (SW-NIR) is a very rapid, versatile and precise technique, which can be used in many different situations and for very types of products and chemical compounds. Extended mul...Short-wavelength near infrared spectroscopy (SW-NIR) is a very rapid, versatile and precise technique, which can be used in many different situations and for very types of products and chemical compounds. Extended multiplicative signal correction (EMSC) is a modification of the standard MSC pre-processing method that allows the separation of physical light scattering effects from chemical (vibrational) light absorbance effects in spectra. In this paper, the EMSC is applied and compared with first derivate, second derivate, MSC and SNV in combination of PLSR to obtain robust models in terms of accuracy and predict ability with a reduced calibration data set using SW-NIR spectra of moisture in marzipan. The Extended Multiplicative Signal Correction—EMSC and combination methods provide the best results in terms of prediction ability and calibration SW-NIR spectra of moisture in marzipan. The best classification results were obtained by Extended Multiplicative Signal Correction followed by second derivates.展开更多
A rapid chromatographic method for the determination of six phenolic acids (chlorogenic, ferulic, gallic, p-coumaric, protocatechuic and vanillic acids) by ultra performance liquid chromatography (UPLC), was developed...A rapid chromatographic method for the determination of six phenolic acids (chlorogenic, ferulic, gallic, p-coumaric, protocatechuic and vanillic acids) by ultra performance liquid chromatography (UPLC), was developed and applied for Brazilian tropical fruits mangaba (Hancornia speciosa Gomes) and umbu (Spondias tuberosa Arruda Camara). A multivariate statistical experimental design was employed to optimize analytical conditions (solvent A, solvent B concentrations and flow rates). Samples were cleaned-up by solid-phase extraction (SPE) with different solvents (methanol and acetone) employing SPE cartridges (amine and octadecyl-silane). The method using dihydrogen potassium phosphate 5 mmoL as solvent A and 8% acetonitrile as solvent B presented limits of detection varying from 14 to 94 ng.mL, limits of quantification from 39 to 277 ng.mL-1 with 2 μL of injection volume while total run time for all six compounds was only 9.6 minutes. Higher recovery was obtained by extraction with methanol-acetone of 69.51% to 72.59% for protocatechuic acid and 69.58% to 126.31% for the chlorogenic acid. The concentrations of chlorogenic, p-coumaric and ferulic acids in mangaba extracts were 113.4, 32.1 and 1.5 μg.g-1, respectively while concentrations of chlorogenic, protocatechuic, gallic, vanillic, ferulic and p-coumaric acids present in umbu fruit were 118.9, 141.3, 3.5, 2.5, 2.2 and 1.8 μg.g-1, respectively.展开更多
This study aimed at evaluating the quality of melon Pele de Sapo “Mabel” and Yellow melon “UFERSA-05” minimally processed preserved in different packages. The fruits were harvested at Mossoró-RN and transport...This study aimed at evaluating the quality of melon Pele de Sapo “Mabel” and Yellow melon “UFERSA-05” minimally processed preserved in different packages. The fruits were harvested at Mossoró-RN and transported to Serra Talhada-PE. In the first study, melon fruit Piel de Sapo “Mabel” was selected, washed, weighed, cooled, peeled, cut into cube shape, sanitized in chlorine solution, drained, packaged in rigid polypropylene tray, sealed with polypropylene film or polypropylene rigid cap and kept for 8 days at 8℃. In the second study, fruits of yellow melon “UFERSA-05” and Pele de Sapo “Mabel” were minimally processed and kept in rigid polypropylene tray, sealed with polypropylene film and stored for 8 days at 8℃. There was no significant interaction between packaging (sealed with film and polypropylene cover) and period of conservation, for pH, total titratable acidity (TTA), total soluble solids (TSS) and Loss of fresh mass (LFM) for Melon “Mabel”. While there was significant interaction between types of melon (“UFERSA-05” and “Mabel”) and storage period (0, 2, 4, 6, and 8 days) for pH, TTA and TSS. In sensory evaluation were noticeable changes in appearance, flavor, aroma and flesh firmness, characterized by translucency, alcoholic aroma and softening in “Mabel” melon kept in tray with lid. Melon “UFERSA-05” showed lower pH, total soluble solids, total soluble sugars, PME activity, lack of translucency high flesh firmness compared to “Mabel” melon during storage. The high levels of sugars in melon “Mabel” may be related to the incidence of translucency, which was not observed in “UFERSA-05” melon, with a strong potential to minimal processing.展开更多
The objective of this work is to develop a low-cost data acquisition system, which aims to optimize the anaerobic biodigestion process in an Indian model biodigester prototype, by monitoring the main parameters of the...The objective of this work is to develop a low-cost data acquisition system, which aims to optimize the anaerobic biodigestion process in an Indian model biodigester prototype, by monitoring the main parameters of the process. In this development, we decided to create a system from scratch, including the entire measure-process-show procedure using hardware tools and free software as means of reducing costs. This platform must be capable of obtaining analog data from the sensors arranged in the biodigester in long periods for the creation of more accurate reports. The system must be able to send this information to a Web server, so these values can be continuously tracked anywhere with access to the internet. The monitoring must be done in a hybrid application for An-droid, iOS and web browser.展开更多
The objective of this work was to evaluate the progress of the areolate mildew of cotton under different soil cover and spacing conditions. The experiment was carried out using randomized blocks and a 2 × 3 facto...The objective of this work was to evaluate the progress of the areolate mildew of cotton under different soil cover and spacing conditions. The experiment was carried out using randomized blocks and a 2 × 3 factorial design, with two spacings (0.45 m and 0.90 m) and three soil covers (no cover, Pennisetum glaucum and Crotalaria spectabilis) with four replications. The plants were inoculated with R. areola, sixty DAS. A total of 14 evaluations of disease severity were performed. At the lower, middle and upper thirds of plants, a diagram scale with nine levels of severity was used and the resulting data were converted into the AUDPC. Gompertz, logistic, and monomolecular mathematical models were tested in the disease severity curves for each third. Agronomics characteristics were evaluated as well. Significant differences of AUDPC were found for the cotton plants thirds, and the middle third was the highest AUDPC. Significant difference for the lower and upper thirds, whose AUDPC were highest on 0.90 m spacing, was observed too. The disease progress curves of the thirds did not fit the tested models. Significant results to the both covers situations, where the treatments grown on crotalária cover and without cover had highest AUDPC, were evidenced. The treatments with C. spectabilis cover were taller than other treatments. Significant data were observed for the cover crops used and in the treatments grown at 0.90 m spacing, to residual cover and crop yield, respectively.展开更多
Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmen...Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmental stages.We investigated leaf nutritional status,and photosynthetic and growth characteristics during the initial establishment of Handroanthus impetiginosus(Mart.Ex Dc.)Mattos,a secondary tree species distributed in the Brazilian Cerrado.Our goal was to understand leaf-level traits related to diff erent aluminum concentrations.H.impetiginosus plants were cultivated in four diff erent aluminum sulfate concentrations:0,1,2,and 4 mM Al,for 40 days.We performed analyses of growth,leaf gas exchange,chloroplast pigment content,and leaf mineral nutrients.We observed a linear increase of Al leaf content as a function of Al concentration in the nutrient solution.Plants grown in 1 mM Al showed a remarkable increase of K leaf content,net photosynthesis,stomatal conductance,and transpiration,while in 4 mM Al there were reductions of N,P,and K contents,gas exchange characteristics,and height.H.impetiginosus did not have mechanisms of avoidance,compartmentalization,or resistance to high Al concentrations.Indeed,this species showed a hormetic response,with low Al concentrations stimulating and high Al concentrations inhibiting plant responses.展开更多
Almost 110 years after the first studies by Dr. Carlos Chagas describing an infectious disease that was named for him, Chagas disease remains a neglected illness and a death sentence for infected people in poor countr...Almost 110 years after the first studies by Dr. Carlos Chagas describing an infectious disease that was named for him, Chagas disease remains a neglected illness and a death sentence for infected people in poor countries. This short review highlights the enormous need for new studies aimed at the development of novel and more specific drugs to treat chagasic patients. The primary tool for facing this challenge is deep knowledge about the similarities and differences between the parasite and its human host.展开更多
The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and t...The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and to evaluate the allelopathic effect of these metabolites on forage legumes for intercropping. Phytochemical prospecting analyses, 1H NMR and capillary electrophoresis were performed on extracts of U. humidicola. Allelopathic activity was evaluated in germination of Stylosanthes, Macrotyloma axillare and Lactuca sativa L. (standard) in the presence of crude extracts, isolated saponins, flavonoids and trans-cinnamic acid. The metabolite classes present in the extracts could be determined by the combined use of the tested analytical techniques, but their use alone was usually not sufficient to chemically characterize the species. Capillary electrophoresis was effective in detecting phenolic compounds. Macrotyloma axillare was tolerant to crude extracts of U. humidicola. Saponins and trans-cinnamic acid, but not the flavonoids, reduced germination of the target plants.展开更多
One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In genera...One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In general, gold refractory ores occurs in various types of deposits associated with a range of minerals. Among the refractory ores, the sulfide type is the most common. The methodology employed in the mining process depends on the mode of occurrence of the ore and on the particle size, shape and degree of purity of the auriferous species. We have undertaken a mineralogical investigation of a representative sample of a complex gold mining ore collected in the municipality of Princesa Isabel, Paraiba, Brazil, using X-ray fluorescence spectrometry, X-ray diffractometry, infrared spectroscopy, inductively coupled plasma-atomic emission spectrometry and the Fire Assay. The results showed that the arsenic content of the ore was closely related to the gold content, and that the occurrence of “invisible gold” was associated primarily with pyrite and secondarily with arsenopyrite. The sulfur content of the ore was directly related to its refractoriness. It is concluded that gold mineralization in the study area is mainly of the gold-quartz-sulfide veins (lode gold), while the gold found in the mini-fractures of the deposits is probably associated with the hydrothermal processes that occurred in the region.展开更多
Currently, the collaboration in scientific communities has been studied in order to explain, among other things, the knowledge diffusion. The quality of Graduate Programmes is often associated with the scientific coll...Currently, the collaboration in scientific communities has been studied in order to explain, among other things, the knowledge diffusion. The quality of Graduate Programmes is often associated with the scientific collaboration. This paper discusses how scientific collaboration processes can be identified and characterized through social and complex networks. For this purpose, collaboration networks of bibliographic production, research projects, and committees of PhD theses and Masters’ dissertations by researchers from a graduate program in computational modeling were studied. The data were obtained from CAPES’ reports of the period from 2001 to 2009. Among the studied indices, centrality indices indicate the presence of prominent researchers who influence others and promptly interact with other researchers in the network. The indices of complex networks reveal the presence of the small-world (i.e. these networks are favorable to increase coordination between researchers) phenomenon and indicate a behavior of scale-free degree distribution (i.e. some researchers promote clustering more than others) for one of the studied networks.展开更多
The genus Physalis belongs to the family Solanaceae,Physalis peruviana L.being the most cultivated species.As a newly explored crop in Brazil,little is known about its germination ecology and emergence under local con...The genus Physalis belongs to the family Solanaceae,Physalis peruviana L.being the most cultivated species.As a newly explored crop in Brazil,little is known about its germination ecology and emergence under local conditions.The aim of the present study was to determine the effect of temperature,photoperiod,planting depth and seed dormancy on the establishment of Physalis seedlings.Tests were conducted on two Physalis biotypes from Sert?o(Rio Grande do Sul state―RS)and Capelinha(Minas Gerais state).Seeds incubated at 27°C and 32°C exhibited high germination percentages of 98%and 96%,respectively.Germination declined when seeds were incubated at 12,17,22 and 37°C.Photoperiods longer than 8 h are sufficient for seed germination,while the absence of light significantly reduces the germination percentage.Seeds should be planted at a depth of 1-2 cm to ensure better seedling emergence.After 18 months of field work,81%of seeds had germinated and/or been predated prior to assessment,indicating low seed dormancy.As such,ideal conditions for Physalis seedling establishment are planting depth between 1 cm and 2 cm,temperatures ranging from 27°C to 32°C and a photoperiod longer than 8 h,with a postharvest seed shelf life of 12 months.展开更多
Projects for energy supply based on the exploitation of renewable energy have a very predictable cash flow. The initial costs are usually high, with the acquisition of technologically evolving equipment. However, main...Projects for energy supply based on the exploitation of renewable energy have a very predictable cash flow. The initial costs are usually high, with the acquisition of technologically evolving equipment. However, maintenance costs are relatively low and easily predictable. Likewise, operating costs are often very low as there is no need to buy inputs. Power storage devices are often short-lived and contribute to a relative cost increase. At the same time, these projects are often not approved because they are directly compared to projects based on non-renewable resources, with cash flows that may not be so easily predictable and with much lower start-up costs. Fossil fuels have hardly predictable costs, established by non-technical criteria and related to geopolitical issues. In addition, their operating costs are usually very high, precisely because of the need to purchase fossil fuels. This paper proposes the calculation of terminal value in cash flows of power generation projects and its application for feasibility analysis of projects based on renewable resources. The proposed method suggests the calculation of terminal value as the moving average calculated for five-year intervals with constant growth rate of 5%. This method also encourages the inclusion in the cash flow of annual values that add up to the end of the analysis period the sufficient value to renew the system components at the end of the usual analysis period of 20 - 25 years. The application of the proposed method to a diesel wind system simulated with the well-known Homer software indicates the modification of the results of the Homer with the preference for systems with greater wind penetration instead of the systems with greater consumption of fossil fuels.展开更多
This paper presents an overview of the state of the art about the late effects of ionizing radiation on skeletal muscle, helping new research and showing unexplored areas. For this, it was evaluated the interest repor...This paper presents an overview of the state of the art about the late effects of ionizing radiation on skeletal muscle, helping new research and showing unexplored areas. For this, it was evaluated the interest reported by the scientific literature regarding the late effects in skeletal muscle resulting from exposure to ionizing radiation. Original and experimental papers mainly containing the key expressions “ionizing radiation” and “effects on skeletal muscle” were searched in computerized databases, and published in any language. Only 33 papers matched the search criteria. Analyzing the investigated radioinduced biological effects in those contributions, four topics were identified as being of major interest: 1) alterations in cellular metabolism and protein degradation;2) repercussions on satellite cells;3) formation of fibrosis and muscle atrophy;4) tissue regeneration. It was verified that no study evaluated possible late effects related to either morphology or properties of skeletal muscles after an exposure to ionizing radiation. Several aspects do not make possible a successful replication;all experiments of eligible group of articles are discussed, such as, lack of raw data, use of no sound methodology and inappropriate statistical technique. Briefly, the subject of this review is an open field of research.展开更多
Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study...Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study was to develop and assess a competitive PCR method for the quantification of toxic and non-toxic Microcystis cells using the cpcBA and mcyB genes, which are respectively involved in the formation of phycocyanin and biosynthesis of microcystin. For the acquisition of competitor DNA, amplification sequences were carried out of the “cell DNA equivalent” of microcystin-producing (BCCUSP18) and non-microcystin-producing (BCCUSP03) strains of Microcystis spp. using primers described in the literature as well as others designed for the present study. The method was successfully developed, as competitor DNA was constructed and co-amplified with the target DNA. Competitive PCR proved to be useful in quantifying toxic and non-toxic cells of Microcystis spp. strains, representing a helpful methodology tool to study isolated toxin-producing cyanobacteria.展开更多
文摘The bioactivity of humic acids (HA) is mainly due to the presence of auxin analogs. In turn, nitric oxide (NO) production in plants affects root growth and may result from endogenous auxin production or the application of synthetic auxin analogs or HA. Nitric oxide signaling may be related to the bioactivity of the HA. Although the auxin, NO, and ROS-mediated activity of HA has been studied, no studies exist on their effects in Ocimum basilicum L., commonly known as basil. A study under controlled in vitro conditions was performed using hairy roots (hairy roots) of basil grown in medium with N-NO3- (0.5 or 5.0 mM) and subjected to treatments with HA (3 mMC·L-1) or sodium nitroprusside (SNP;100 μM), an NO donor, either without or with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO;200 μM), an NO scavenger. The addition of HA and SNP resulted in significant increases in the root growth, associated with increased NO and reactive oxygen species (ROS) contents. The application of the NO scavenger cPTIO with the SNP and HA decreased the effects of both substances on the root growth and endogenous levels of the NO and ROS. The increased root growth promoted by the NO donor (SNP) and HA was also associated with increased proton pump and catalase activity for both N-NO3- levels tested. The results showed that the effects of HA are dependent on NO and ROS, which act as messengers, inducing root growth.
基金CAPES(Coordenacao de Aperfeicoamento de Pessoal de Nível Superior),CNPq(Conselho Nacional de Desenvolvimento Cientifico e Tecnologico),FINEP(Financiadora de Estudos e Projetos),and the Instituto Federal Goiano—Campus Rio Verde,for their financial support.
文摘The fodder radish is an important alternative late summer crop in central-western Brazil. The fodder radish has a short growing cycle, is highly productive and possesses qualities that enhance its cultivation potential as an alternative in Brazil’s Biodiesel Program. However, drift of herbicides, such as glyphosate, may hinder the development of fodder radishes. Studies of chlorophyll fluorescence can provide measurements that help assess the effect of herbicide, being good indicator of the damage to photosynthetic apparatus promoted by herbicide. This study was carried out to analyze the effects of glyphosate by measuring chlorophyll a fluorescence, cellular membrane stability and chloroplast pigment contents in fodder radish plants. This experiment used a randomized block design in which the treatments consisted of the following 6 different doses: control, 0, 150, 300, 450, 600, 750 and 900 g i.a. ha-1 of the recommended 480 g·L-1 dose of glyphosate acid equivalent. The plants were sprayed 30 days after emergence and were assessed every 48 hours. The characteristics evaluated, including chlorophyll a fluorescence, chloroplast pigments and the rate of electrolyte leakage, indicated that radish plants are sensitive to glyphosate because the treatments resulted in reduced levels of photosynthetic efficiency and increased damage to cellular membranes, which led to a reduction in the chloroplast pigment content.
文摘The production of mushrooms enriched with essential elements, e.g. selenium, for human health is an interesting strategy to improve the functional foods supply. The selenium is an essential mineral and makes part of structure of enzymes involved in the oxidative metabolism. However, the selenium effect on the activity of respiratory and lignocellulolytic enzymes has not been considered. The understanding of this effect is important to determine the selenium concentration that increases the mushroom productivity and the degradation rate of the substrate. In this study, it was observed reduction of the respiratory activity of Lentinula edodes (Berk.) Pegler, the shiitake mushroom, in function of the increasing of the sodium selenite concentration in the substrate (p < 0.05). Selenium did not inhibit the activity of the hydrolytic enzymes (cellulase and xylanase), but it increased the activity of the oxidative enzyme (laccase). Respiratory activity of L. edodes has a negative correlation with sodium selenite concentration added in substrate. Thus is important to define the ideal dose of selenium to be added to the substrate for increasing lignocellulosic residues degradation and, consequently, guarantee a higher production of Se-enriched mushrooms.
文摘Short-wavelength near infrared spectroscopy (SW-NIR) is a very rapid, versatile and precise technique, which can be used in many different situations and for very types of products and chemical compounds. Extended multiplicative signal correction (EMSC) is a modification of the standard MSC pre-processing method that allows the separation of physical light scattering effects from chemical (vibrational) light absorbance effects in spectra. In this paper, the EMSC is applied and compared with first derivate, second derivate, MSC and SNV in combination of PLSR to obtain robust models in terms of accuracy and predict ability with a reduced calibration data set using SW-NIR spectra of moisture in marzipan. The Extended Multiplicative Signal Correction—EMSC and combination methods provide the best results in terms of prediction ability and calibration SW-NIR spectra of moisture in marzipan. The best classification results were obtained by Extended Multiplicative Signal Correction followed by second derivates.
基金All authors thank the financial support provided from the project,National Institute of Science and Technology(INCT)for Tropical Fruits from CNPq,Brazil offered for promoting research work undertaken in this studyThe co-authors(Edelvio and Rita)thank CAPES(Ministry of Education,Brazil)for providing fellowship to them.
文摘A rapid chromatographic method for the determination of six phenolic acids (chlorogenic, ferulic, gallic, p-coumaric, protocatechuic and vanillic acids) by ultra performance liquid chromatography (UPLC), was developed and applied for Brazilian tropical fruits mangaba (Hancornia speciosa Gomes) and umbu (Spondias tuberosa Arruda Camara). A multivariate statistical experimental design was employed to optimize analytical conditions (solvent A, solvent B concentrations and flow rates). Samples were cleaned-up by solid-phase extraction (SPE) with different solvents (methanol and acetone) employing SPE cartridges (amine and octadecyl-silane). The method using dihydrogen potassium phosphate 5 mmoL as solvent A and 8% acetonitrile as solvent B presented limits of detection varying from 14 to 94 ng.mL, limits of quantification from 39 to 277 ng.mL-1 with 2 μL of injection volume while total run time for all six compounds was only 9.6 minutes. Higher recovery was obtained by extraction with methanol-acetone of 69.51% to 72.59% for protocatechuic acid and 69.58% to 126.31% for the chlorogenic acid. The concentrations of chlorogenic, p-coumaric and ferulic acids in mangaba extracts were 113.4, 32.1 and 1.5 μg.g-1, respectively while concentrations of chlorogenic, protocatechuic, gallic, vanillic, ferulic and p-coumaric acids present in umbu fruit were 118.9, 141.3, 3.5, 2.5, 2.2 and 1.8 μg.g-1, respectively.
基金The authors thank the Universidade Federal Rural do Pernambuco,the Universidade Federal Rural do Semiárido,CNPq,FACEPE and CAPES for the financial support.
文摘This study aimed at evaluating the quality of melon Pele de Sapo “Mabel” and Yellow melon “UFERSA-05” minimally processed preserved in different packages. The fruits were harvested at Mossoró-RN and transported to Serra Talhada-PE. In the first study, melon fruit Piel de Sapo “Mabel” was selected, washed, weighed, cooled, peeled, cut into cube shape, sanitized in chlorine solution, drained, packaged in rigid polypropylene tray, sealed with polypropylene film or polypropylene rigid cap and kept for 8 days at 8℃. In the second study, fruits of yellow melon “UFERSA-05” and Pele de Sapo “Mabel” were minimally processed and kept in rigid polypropylene tray, sealed with polypropylene film and stored for 8 days at 8℃. There was no significant interaction between packaging (sealed with film and polypropylene cover) and period of conservation, for pH, total titratable acidity (TTA), total soluble solids (TSS) and Loss of fresh mass (LFM) for Melon “Mabel”. While there was significant interaction between types of melon (“UFERSA-05” and “Mabel”) and storage period (0, 2, 4, 6, and 8 days) for pH, TTA and TSS. In sensory evaluation were noticeable changes in appearance, flavor, aroma and flesh firmness, characterized by translucency, alcoholic aroma and softening in “Mabel” melon kept in tray with lid. Melon “UFERSA-05” showed lower pH, total soluble solids, total soluble sugars, PME activity, lack of translucency high flesh firmness compared to “Mabel” melon during storage. The high levels of sugars in melon “Mabel” may be related to the incidence of translucency, which was not observed in “UFERSA-05” melon, with a strong potential to minimal processing.
文摘The objective of this work is to develop a low-cost data acquisition system, which aims to optimize the anaerobic biodigestion process in an Indian model biodigester prototype, by monitoring the main parameters of the process. In this development, we decided to create a system from scratch, including the entire measure-process-show procedure using hardware tools and free software as means of reducing costs. This platform must be capable of obtaining analog data from the sensors arranged in the biodigester in long periods for the creation of more accurate reports. The system must be able to send this information to a Web server, so these values can be continuously tracked anywhere with access to the internet. The monitoring must be done in a hybrid application for An-droid, iOS and web browser.
基金thank the Coordination for the Improvement of Higher Education Personnel(CAPES),for the grant given to the first authorto the Graduate Environment and Agricultural Production Systems Program(PPGAT)and all faculty members for the support and assistance given during the study period.
文摘The objective of this work was to evaluate the progress of the areolate mildew of cotton under different soil cover and spacing conditions. The experiment was carried out using randomized blocks and a 2 × 3 factorial design, with two spacings (0.45 m and 0.90 m) and three soil covers (no cover, Pennisetum glaucum and Crotalaria spectabilis) with four replications. The plants were inoculated with R. areola, sixty DAS. A total of 14 evaluations of disease severity were performed. At the lower, middle and upper thirds of plants, a diagram scale with nine levels of severity was used and the resulting data were converted into the AUDPC. Gompertz, logistic, and monomolecular mathematical models were tested in the disease severity curves for each third. Agronomics characteristics were evaluated as well. Significant differences of AUDPC were found for the cotton plants thirds, and the middle third was the highest AUDPC. Significant difference for the lower and upper thirds, whose AUDPC were highest on 0.90 m spacing, was observed too. The disease progress curves of the thirds did not fit the tested models. Significant results to the both covers situations, where the treatments grown on crotalária cover and without cover had highest AUDPC, were evidenced. The treatments with C. spectabilis cover were taller than other treatments. Significant data were observed for the cover crops used and in the treatments grown at 0.90 m spacing, to residual cover and crop yield, respectively.
基金This study was financed in part by the Coordenacao de Aperfeicamento de Pessoal de Nível Superior-Brazil(CAPES)-Financial Code 001 and the Conselho Nacional de Desenvolvimento Científicoe Tecnológico-Brazil(CNPq)by providing scholarship for the authors.
文摘Cerrado soils are acidic and nutrient-poor,with high content of solubilized Al 3+.Plants growing in these conditions may display adaptations to cope with high aluminum concentrations especially during early developmental stages.We investigated leaf nutritional status,and photosynthetic and growth characteristics during the initial establishment of Handroanthus impetiginosus(Mart.Ex Dc.)Mattos,a secondary tree species distributed in the Brazilian Cerrado.Our goal was to understand leaf-level traits related to diff erent aluminum concentrations.H.impetiginosus plants were cultivated in four diff erent aluminum sulfate concentrations:0,1,2,and 4 mM Al,for 40 days.We performed analyses of growth,leaf gas exchange,chloroplast pigment content,and leaf mineral nutrients.We observed a linear increase of Al leaf content as a function of Al concentration in the nutrient solution.Plants grown in 1 mM Al showed a remarkable increase of K leaf content,net photosynthesis,stomatal conductance,and transpiration,while in 4 mM Al there were reductions of N,P,and K contents,gas exchange characteristics,and height.H.impetiginosus did not have mechanisms of avoidance,compartmentalization,or resistance to high Al concentrations.Indeed,this species showed a hormetic response,with low Al concentrations stimulating and high Al concentrations inhibiting plant responses.
文摘Almost 110 years after the first studies by Dr. Carlos Chagas describing an infectious disease that was named for him, Chagas disease remains a neglected illness and a death sentence for infected people in poor countries. This short review highlights the enormous need for new studies aimed at the development of novel and more specific drugs to treat chagasic patients. The primary tool for facing this challenge is deep knowledge about the similarities and differences between the parasite and its human host.
文摘The aim of this study was to identify the main classes of secondary metabolites present in the root and shoot crude extracts and fractions from the forage grass Urochloa humidicola (Rendle) Morrone & Zuloaga and to evaluate the allelopathic effect of these metabolites on forage legumes for intercropping. Phytochemical prospecting analyses, 1H NMR and capillary electrophoresis were performed on extracts of U. humidicola. Allelopathic activity was evaluated in germination of Stylosanthes, Macrotyloma axillare and Lactuca sativa L. (standard) in the presence of crude extracts, isolated saponins, flavonoids and trans-cinnamic acid. The metabolite classes present in the extracts could be determined by the combined use of the tested analytical techniques, but their use alone was usually not sufficient to chemically characterize the species. Capillary electrophoresis was effective in detecting phenolic compounds. Macrotyloma axillare was tolerant to crude extracts of U. humidicola. Saponins and trans-cinnamic acid, but not the flavonoids, reduced germination of the target plants.
基金the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico(CNPq,grant no.550261/2010-9)for financial support
文摘One of the most important problems facing the gold industry is that the placer and free milling gold ores are almost terminating. Hence, the use of refractory ores has been increased during the recent years. In general, gold refractory ores occurs in various types of deposits associated with a range of minerals. Among the refractory ores, the sulfide type is the most common. The methodology employed in the mining process depends on the mode of occurrence of the ore and on the particle size, shape and degree of purity of the auriferous species. We have undertaken a mineralogical investigation of a representative sample of a complex gold mining ore collected in the municipality of Princesa Isabel, Paraiba, Brazil, using X-ray fluorescence spectrometry, X-ray diffractometry, infrared spectroscopy, inductively coupled plasma-atomic emission spectrometry and the Fire Assay. The results showed that the arsenic content of the ore was closely related to the gold content, and that the occurrence of “invisible gold” was associated primarily with pyrite and secondarily with arsenopyrite. The sulfur content of the ore was directly related to its refractoriness. It is concluded that gold mineralization in the study area is mainly of the gold-quartz-sulfide veins (lode gold), while the gold found in the mini-fractures of the deposits is probably associated with the hydrothermal processes that occurred in the region.
基金financial support from CNPq(the Brazilian federal grant agency).
文摘Currently, the collaboration in scientific communities has been studied in order to explain, among other things, the knowledge diffusion. The quality of Graduate Programmes is often associated with the scientific collaboration. This paper discusses how scientific collaboration processes can be identified and characterized through social and complex networks. For this purpose, collaboration networks of bibliographic production, research projects, and committees of PhD theses and Masters’ dissertations by researchers from a graduate program in computational modeling were studied. The data were obtained from CAPES’ reports of the period from 2001 to 2009. Among the studied indices, centrality indices indicate the presence of prominent researchers who influence others and promptly interact with other researchers in the network. The indices of complex networks reveal the presence of the small-world (i.e. these networks are favorable to increase coordination between researchers) phenomenon and indicate a behavior of scale-free degree distribution (i.e. some researchers promote clustering more than others) for one of the studied networks.
文摘The genus Physalis belongs to the family Solanaceae,Physalis peruviana L.being the most cultivated species.As a newly explored crop in Brazil,little is known about its germination ecology and emergence under local conditions.The aim of the present study was to determine the effect of temperature,photoperiod,planting depth and seed dormancy on the establishment of Physalis seedlings.Tests were conducted on two Physalis biotypes from Sert?o(Rio Grande do Sul state―RS)and Capelinha(Minas Gerais state).Seeds incubated at 27°C and 32°C exhibited high germination percentages of 98%and 96%,respectively.Germination declined when seeds were incubated at 12,17,22 and 37°C.Photoperiods longer than 8 h are sufficient for seed germination,while the absence of light significantly reduces the germination percentage.Seeds should be planted at a depth of 1-2 cm to ensure better seedling emergence.After 18 months of field work,81%of seeds had germinated and/or been predated prior to assessment,indicating low seed dormancy.As such,ideal conditions for Physalis seedling establishment are planting depth between 1 cm and 2 cm,temperatures ranging from 27°C to 32°C and a photoperiod longer than 8 h,with a postharvest seed shelf life of 12 months.
基金This work was developed as a part of research activities on renewable energy developed at the Instituto de Pesquisas Hidráulicas,Universidade Federal do Rio Grande do SulThe authors acknowledge the support received by the institutionThe second author acknowledges the financial support received from CNPq(proc.n.309021/2014-6)for his research work.
文摘Projects for energy supply based on the exploitation of renewable energy have a very predictable cash flow. The initial costs are usually high, with the acquisition of technologically evolving equipment. However, maintenance costs are relatively low and easily predictable. Likewise, operating costs are often very low as there is no need to buy inputs. Power storage devices are often short-lived and contribute to a relative cost increase. At the same time, these projects are often not approved because they are directly compared to projects based on non-renewable resources, with cash flows that may not be so easily predictable and with much lower start-up costs. Fossil fuels have hardly predictable costs, established by non-technical criteria and related to geopolitical issues. In addition, their operating costs are usually very high, precisely because of the need to purchase fossil fuels. This paper proposes the calculation of terminal value in cash flows of power generation projects and its application for feasibility analysis of projects based on renewable resources. The proposed method suggests the calculation of terminal value as the moving average calculated for five-year intervals with constant growth rate of 5%. This method also encourages the inclusion in the cash flow of annual values that add up to the end of the analysis period the sufficient value to renew the system components at the end of the usual analysis period of 20 - 25 years. The application of the proposed method to a diesel wind system simulated with the well-known Homer software indicates the modification of the results of the Homer with the preference for systems with greater wind penetration instead of the systems with greater consumption of fossil fuels.
文摘This paper presents an overview of the state of the art about the late effects of ionizing radiation on skeletal muscle, helping new research and showing unexplored areas. For this, it was evaluated the interest reported by the scientific literature regarding the late effects in skeletal muscle resulting from exposure to ionizing radiation. Original and experimental papers mainly containing the key expressions “ionizing radiation” and “effects on skeletal muscle” were searched in computerized databases, and published in any language. Only 33 papers matched the search criteria. Analyzing the investigated radioinduced biological effects in those contributions, four topics were identified as being of major interest: 1) alterations in cellular metabolism and protein degradation;2) repercussions on satellite cells;3) formation of fibrosis and muscle atrophy;4) tissue regeneration. It was verified that no study evaluated possible late effects related to either morphology or properties of skeletal muscles after an exposure to ionizing radiation. Several aspects do not make possible a successful replication;all experiments of eligible group of articles are discussed, such as, lack of raw data, use of no sound methodology and inappropriate statistical technique. Briefly, the subject of this review is an open field of research.
基金supported by grants from“Fundacao de Amparoa Pesquisa do Estado de Sao Paulo”(Proc.2007/57672-0)CNPq(Proc.301739/2011-0)-Brazilian agencies for the promotion of Science.
文摘Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study was to develop and assess a competitive PCR method for the quantification of toxic and non-toxic Microcystis cells using the cpcBA and mcyB genes, which are respectively involved in the formation of phycocyanin and biosynthesis of microcystin. For the acquisition of competitor DNA, amplification sequences were carried out of the “cell DNA equivalent” of microcystin-producing (BCCUSP18) and non-microcystin-producing (BCCUSP03) strains of Microcystis spp. using primers described in the literature as well as others designed for the present study. The method was successfully developed, as competitor DNA was constructed and co-amplified with the target DNA. Competitive PCR proved to be useful in quantifying toxic and non-toxic cells of Microcystis spp. strains, representing a helpful methodology tool to study isolated toxin-producing cyanobacteria.
