Background:Hemodialysis(HD) per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the...Background:Hemodialysis(HD) per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model.The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this molecule.Methods:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of <15 mL/min/1.73 m2).The RE+BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning specialist.Results:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD vintage.Furthermore,RE+BFR significantly increases D-dimer after 4 h.Patients with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.展开更多
Ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural regeneration.Variation in oxygen concentration among diverse tissues necessita...Ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural regeneration.Variation in oxygen concentration among diverse tissues necessitates the precise recreation of tissue-specific oxygen levels in imprinted constructs to support the survival of targeted cells.Although oxygen-releasing biomaterials,such as oxygen-generating microparticles(OMPs),have shown promise for enhancing the oxygen supply of microenvironments in injured tissues,whether this approach is scalable for large tissues and whether tissue-specific bioinks with varying OMP concentrations remain printable remain unknown.This study addresses this critical gap by introducing an innovative class of engineered oxygenated bioinks that combine colloidal-based microgels with OMPs.We report that incorporating nanosized calcium peroxide(nCaO_(2))and manganese oxide nanosheets(nMnO_(2))into hydrophobic polymeric microparticles enables precise modulation of oxygen release while controlling hydrogen peroxide release.Moreover,the fabrication of oxygenating and cytocompatible colloidal gels is achieved using an aqueous two-phase system.This study thoroughly evaluates the fundamental characteristics of the resulting bioink,including its rheological behaviors,printability,shape fidelity,mechanical properties,and oxygen release properties.Moreover,this study demonstrates the macroscopic scalability and cytocompatibility of printed constructs produced via cell-laden oxygenating colloidal bioinks.By showcasing the effectiveness of extrusion-based bioprinting,this study underscores how it can be used to fabricate biomimetic tissues,indicating its potential for new applications.The findings presented here advance the bioprinting field by achieving scalability with both high cell viability and the possibility of mimicking specifically oxygenated tissues.This work thereby offers a promising avenue for the development of functional tissues with enhanced physiological relevance.展开更多
Dear editor:We sincerely thank Matthew J.Clarkson for his insightful commentary1 on our recent publication in the Journal of Sport and Health Science.2 Clarkson's pioneering work in the development and application...Dear editor:We sincerely thank Matthew J.Clarkson for his insightful commentary1 on our recent publication in the Journal of Sport and Health Science.2 Clarkson's pioneering work in the development and application of blood flow restriction (BFR) exercise protocols has undeniably laid the groundwork for subsequent investigations in this field,including our own.(3-6)His commentary not only highlights the relevance and timeliness of our study but also offers valuable perspectives on refining safety considerations for intradialytic BFR exercise among hemodialysis patients.展开更多
Soymilk is one of the most available beverages, an alternative to dairy milk and is recognized for its nutritional value. The nutritional quality, the presence of anti-nutritional factors, isoflavones and sensory acce...Soymilk is one of the most available beverages, an alternative to dairy milk and is recognized for its nutritional value. The nutritional quality, the presence of anti-nutritional factors, isoflavones and sensory acceptability of soymilk depended on the soybean variety as well as the processing conditions. The soymilks from conventional and specialty Brazilian soybean cultivars were compared regarding the composition and consumer acceptance. There were significant differences on the protein, oil, sugars, isoflavones, presence of anti-nutritional factors (phytate and trypsin inhibitor activity) and NSI (nitrogen solubility index) among cultivars and soymilks and for sensory acceptance of soymilks. The preference mapping and cluster analysis identified three different segments of consumers. The soymilk from the conventional cultivar BRS284 achieved higher and similar acceptance score for the three consumer’s segments while the lipoxygenase free cultivars (BRS213 and BRS257) and specialty cultivar BRS216 showed higher score for two segments of consumers. The sensory evaluation of soymilk from different soybean cultivars could improve consumer uptake.展开更多
Coffee is highly appreciated as stimulant. Brazil is the first producer and second consumer in the world. Flower evocation triggered by environmental signals is essential for adaptability and productivity, and despite...Coffee is highly appreciated as stimulant. Brazil is the first producer and second consumer in the world. Flower evocation triggered by environmental signals is essential for adaptability and productivity, and despite that it is neglected and barely considered as a part of the reproductive cycle. Aiming to review molecular mechanisms producing phenological responses observed in the fields, orthologs to A. thaliana CO, FLC/FLM, FLT, SOC and VRN genes were identified in silico for C. arabica and its ancestors C. canephora and C. eugenioides. Protein structures and conserved domains, regulatory elements in promoters, and the related literature in both genera were accessed and compared. Hypotheses regarding Coffea spp. orthologs responsiveness to light and temperature signals at the tropics are proposed. Preliminary analysis of phenological data taken from early, intermediary and late C. arabica plants are included to illustrate the diversity regarding flower bud emission, which quite certainly is defined during flower evocation.展开更多
“Pinhão”, the seed of Araucaria angustifolia, is an important food, being part of the eating habits of Indigenous communities. In this study, we evaluated the oligosaccharide content, resistant starch and the g...“Pinhão”, the seed of Araucaria angustifolia, is an important food, being part of the eating habits of Indigenous communities. In this study, we evaluated the oligosaccharide content, resistant starch and the growth of probiotic bacteria. GF4 (1-fructofuranosylnystose) was the main fructo-oligosaccharides found, in higher contents compared to other food sources. Maltooligosaccharides (MOS) represented the main part of the oligosaccharides profile of Brazilian pine seeds. In descending order of importance was maltoheptaose (G7), maltohexose (G6) and maltotriose (G3). The starches from the variety Sanct josephi presented the highest amount of resistant starch that could stimulate probiotic strains, mainly B. breve and L. plantarum, and may have a prebiotic effect, potentially promoting health benefits. This study advances the understanding of the chemical composition of the main portion of the “pinhão” enhancing awareness of its potential as a healthy food source, contributing to different uses and indirectly with the species preservation.展开更多
Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grow...Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on P.taeda were analyzed for various elements and properties.All soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple elements.YNC symptoms started at needle tips,then extended toward the needle base with time.First flush needles had longer portions with YNC than second flush needles did.Needles from the lower crown also had more symptoms along their length than those higher in the canopy.Symptoms were similar to those reported for Mg.In chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of P.taeda in various parent soils in Brazil.展开更多
Selective logging is well-recognized as an effective practice in sustainable forest management.However,the ecological efficiency or resilience of the residual stand is often in doubt.Recovery time depends on operation...Selective logging is well-recognized as an effective practice in sustainable forest management.However,the ecological efficiency or resilience of the residual stand is often in doubt.Recovery time depends on operational variables,diversity,and forest structure.Selective logging is excellent but is open to changes.This may be resolved by mathematical programming and this study integrates the economic-ecological aspects in multi-objective function by applying two evolutionary algorithms.The function maximizes remaining stand diversity,merchantable logs,and the inverse of distance between trees for harvesting and log landings points.The Brazilian rainforest database(566 trees)was used to simulate our 216-ha model.The log landing design has a maximum volume limit of 500 m3.The nondominated sorting genetic algorithm was applied to solve the main optimization problem.In parallel,a sub-problem(p-facility allocation)was solved for landing allocation by a genetic algorithm.Pareto frontier analysis was applied to distinguish the gradientsα-economic,β-ecological,andγ-equilibrium.As expected,the solutions have high diameter changes in the residual stand(average removal of approximately 16 m^(3) ha^(-1)).All solutions showed a grouping of trees selected for harvesting,although there was no formation of large clearings(percentage of canopy removal<7%,with an average of 2.5 ind ha^(-1)).There were no differences in floristic composition by preferentially selecting species with greater frequency in the initial stand for harvesting.This implies a lower impact on the demographic rates of the remaining stand.The methodology should support projects of reduced impact logging by using spatial-diversity information to guide better practices in tropical forests.展开更多
Eucalyptus harvest residues are attractive energy production resources for the forestry industry.However,their removal can have adverse impacts on soil quality and forest productivity,especially in sandy soils.In this...Eucalyptus harvest residues are attractive energy production resources for the forestry industry.However,their removal can have adverse impacts on soil quality and forest productivity,especially in sandy soils.In this study,we assessed the effects of Eucalyptus harvest residue managements with variable intensity on forest productivity and on physical,chemical,and biological indicators of the soil quality.The experiment was conducted in a Quartzipsamment(33 g kg-1clay)planted with Eucalyptus saligna in Barra do Ribeiro in southern Brazil.Before the Eucalyptus was planted,residues from the previous rotation were subjected to five different management treatments:(1)FRM,in which all forest residues(bark,branches,leaves,and litter)were allowed to remain on the soil and only trunk wood was removed;(2)FRMB,in which was identical to FRM except that bark was also removed;(3)FRMBr,in which only trunk wood and branches were removed;(4)FRR,which involved removing all types of residues(bark,branches,leaves,and litter);and,(5)FRRs,in which all forest residues from the previous rotation were removed,and leaves and branches from the new plantation were prevented from falling onto the soil surface using a shade net.Six years after planting,soil samples were collected at four different depths(0-2.5,2.5-5,5-10,and 10-20 cm)to determine 17 soil chemical,physical,and biological indicators.The results were combined into a soil quality index(SQI)using the principal component analysis approach.The SQI reduced by 30%,in the 0-20 cm layer,due to removal of harvest residues from the previous rotation,and collection of litter before it falls on the ground.The main drivers of SQI reduction were the principal components associated with soil organic matter and biological activity.Furthermore,the SQI was positively linearly related to tree height at P<0.01 and to tree diameter at breast height at P=0.07.The adverse impact on soil quality and forest productivity in our study indicates that removal of Eucalyptus harvest residues from sandy soils should be avoided.展开更多
An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To se...An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To select soil quality indicator variables in sugarcane (Saccharum officinarum L.) production areas that fulfill the criteria of sensitivity to management practices and between-season consistency in the management discrimination, ten composite soil samples (0–10 cm) were collected in July 2005 (rainy season) and again in March 2006 (dry season) from areas under cultivation of organic sugarcane (OS), green sugarcane (GS), burned sugarcane (BS) and from an adjacent native forest (NF) area at Usina Triunfo, Boca da Mata, Alagoas, Brazil. Microbial biomass-C (MBC), total organic C (TOC), soil enzyme activity expressed as the rate of fluorescein diacetate (FDA) hydrolysis, mean weight diameter of water-stable soil aggregates (MWD), and percentage of water-stable macroaggregates (PWSA) were analyzed. Although MBC and TOC were higher in NF than in the cultivated areas, no differences were observed in these C pools between the three sugarcane systems. The response of FDA to the site management was dependent on the sampling time. In the rainy period, the activity followed the order: NF > OS > GS > BS, whereas in the dry season, only NF differed from the other treatments. Irrespective of the sampling time, MWD and PWSA decreased in the order NF > OS = GS > BS. The variables MWD and PWSA are quite sensitive for discriminating between site management histories regardless the sampling season.展开更多
Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determ...Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops(cultivated in the offseason) in the soybean-upland rice rotation(cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4 × 2 with six replications. Treatments were composed by four cover crops: fallow, millet(Pennisetum glaucum) + Crotalaria ochroleuca, millet + pigeon pea(Cajanus cajans), and millet + pigeon pea + Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice(Oryza sativa)or soybean(Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced p H, Al and H + Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet + pigeon pea and millet + pigeon pea + U. ruziziensis improved soil physical properties in relation to fallow,especially in the 0–0.10 m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover crops.Soybean grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops.展开更多
Legume nodulation by rhizobia can supply crops with nitrogen and reduce environmental impacts caused by chemical fertilization. The soybean crop in Brazil is an impressive example of how biological N2 fixation can be ...Legume nodulation by rhizobia can supply crops with nitrogen and reduce environmental impacts caused by chemical fertilization. The soybean crop in Brazil is an impressive example of how biological N2 fixation can be employed with a plant species of high economic value. However, the development of more productive cultivars, along with the increasing global climatic changes demand agricultural practices to become more productive and yet more environmentally friendly. Plant growth-promoting rhizobacteria (PGPR) are highly beneficial to agriculture worldwide, acting in plant nutrition, protection, and growth stimulation. Azospirillum is, certainly, the most employed PGPR in the world, but little is known about its interaction with rhizobia, when both are applied to legume seeds. We have evaluated the co-inoculation of bradyrhizobia and azospirilla on soybean seeds under different soil and climate conditions in Brazil. Our results demonstrated that co-inoculation is efficient and beneficial to the crop, and promotes yield increases without adding any chemical N fertilizers even in soils where established populations of soybean bradyrhizobia exist. The strategy of co-inoculation thus represents a new biotechnological tool to improve soybean yield without adding any chemical N fertilizers, thus contributing to current practices of sustainability in agriculture.展开更多
The Dof(DNA-binding with one finger)protein family spans a group of plant transcription factors involved in the regulation of several functions,such as plant responses to stress,hormones and light,phytochrome signalin...The Dof(DNA-binding with one finger)protein family spans a group of plant transcription factors involved in the regulation of several functions,such as plant responses to stress,hormones and light,phytochrome signaling and seed germination.Here we describe the Dof-like gene family in grapevine(Vitis vinifera L.),which consists of 25 genes coding for Dof.An extensive in silico characterization of the VviDofL gene family was performed.Additionally,the expression of the entire gene family was assessed in 54 grapevine tissues and organs using an integrated approach with microarray(cv Corvina)and real-time PCR(cv Pinot Noir)analyses.The phylogenetic analysis comparing grapevine sequences with those of Arabidopsis,tomato,poplar and already described Dof genes in other species allowed us to identify several duplicated genes.The diversification of grapevine DofL genes during evolution likely resulted in a broader range of biological roles.Furthermore,distinct expression patterns were identified between samples analyzed,corroborating such hypothesis.Our expression results indicate that several VviDofL genes perform their functional roles mainly during flower,berry and seed development,highlighting their importance for grapevine growth and production.The identification of similar expression profiles between both approaches strongly suggests that these genes have important regulatory roles that are evolutionally conserved between grapevine cvs Corvina and Pinot Noir.展开更多
A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grand& plantations in the semiarid region ( 15...A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grand& plantations in the semiarid region ( 15° 09′ S 43° 49′ W) in the north of the State of Minas Gerais in Brazil. Results show that the total above-ground biomass (dry matter) was 33.6 Mg.ha^-1 for E. camaldulensis and 53.1 Mg·ha^-1 for E. grandis. The biomass of the stem wood, leaves, branches, and stein bark for E. camaldulens accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively (Table 2); meanwhile a similar partition of the total above-ground biomass was also found for E. grand&. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%, 0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk (bark and wood), nutrient accumulation in general was lower. Nutrient content of E. grand& presented little variation compared with that orE. camaJd^llensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of nutrients, especially in E. grand&. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this semi-arid region. The two species showed mycotrophy.展开更多
Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still ...Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still use seeds instead of clones as initial explants.This work aimed to develop a genetic transformation protocol,based on a highly efficient in vitro organogenesis protocol,for an Eucalyptus urophylla clone selected in our breeding program.Plant growth regulators were evaluated for indirect organogenesis and rooting.In a two-step protocol,the combination of callus induction media supplemented with 0.5 μM thidiazuron+0.5 μM naphthaleneacetic acid(NAA)and shoot induction media supplemented with 5.0 μM benzylaminopurine+1.0 lM NAA allowed up to 85.6%shoot formation with more shoots per explants when compared with other concentrations.Transgenic plants expressing the uidA gene were obtained using Agrobacterium tumefaciens and selected for kanamycin resistance.A RAPD analysis was used to check for somaclonal variation.In tests using 11 RAPD primers,we did not observe somaclonal variation in the in vitro stages evaluated.展开更多
A longer stem elongation phase (from the terminal spikelet-TS to the anthesis-ANT phases) increases grain production due to an increase in spikelet fertility. However, the mechanism behind the greater number of fertil...A longer stem elongation phase (from the terminal spikelet-TS to the anthesis-ANT phases) increases grain production due to an increase in spikelet fertility. However, the mechanism behind the greater number of fertile flowers that occur when the duration of stem elongation is modified by photoperiod and vernalization is not fully understood. The goal of this study was to investigate the effect of combinations of photoperiod and vernalization on the duration of stem elongation and spikelet fertility in wheat. Thus, a greenhouse experiment was performed by subjecting 13 wheat genotypes to two vernalization regimes (V0—non-vernalized plants and V40—plants with 40 vernalization days) and to two photoperiod regimes (NP—natural and NP + 6—photoperiod extended by six hours), during the stem elongation phase. The natural photoperiod increased the spikelet fertility of eight cultivars without a corresponding increased duration of the TS-ANT phase, suggesting the existence of a direct effect of photoperiod on increased spikelet fertility. Vernalization increased the duration of the TS-ANT phase, without influencing spikelet fertility. There was genetic variability in the responses to photoperiod and vernalization.展开更多
The conversion of sugarcane lignocellulosic biomass into fuels,chemicals and high-value materials using the biochemical pathway is considered the most sustainable alternative for the implementation of future biorefine...The conversion of sugarcane lignocellulosic biomass into fuels,chemicals and high-value materials using the biochemical pathway is considered the most sustainable alternative for the implementation of future biorefineries.Actually,the first large-scale cellulosic ethanol plants that have started operating worldwide apply the enzymatic hydrolysis process to convert biomass into simple sugars that are fermented to ethanol by yeasts.However,several technological challenges still need to be addressed in order to obtain commercially competitive products.This review describes current challenges and perspectives regarding the enzymatic hydrolysis step for processing sugarcane lignocellulosic biomass within the biorefinery.Recent developments in terms of process configuration strategies and opportunities for the implementation of a sugarcane biorefinery,in which the production of ethanol is integrated into the production of high-value products such as enzymes and nanocellulose,are discussed in view of the demands of the current bioeconomy.展开更多
基金supported by a grant provided by the Coordenacao de Aperfeicoamento de Pessoal de Nível Superior-Brazil-Finance Code 001 and National Council for Scientific and Technological Developmentfinanced in part by the Conselho Nacional de Desenvolvimento Científico e Tecnológico and Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-Brasil--Finance Code 001funded by the Fundacao de Apoio à Pesquisa do Distrito Federal with grants from demanda espontanea-Edital 09/2022
文摘Background:Hemodialysis(HD) per se is a risk factor for thrombosis.Considering the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model.The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this molecule.Methods:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of <15 mL/min/1.73 m2).The RE+BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD(intradialytic exercise).RE repetitions included concentric and eccentric lifting phases(each lasting 2 s) and were supervised by a strength and conditioning specialist.Results:Several variables were associated with elevated levels of D-dimer,including higher blood glucose,citrate use,recent cardiovascular events,recent intercurrents,higher inflammatory status,catheter as vascular access,older patients(>70 years old),and HD vintage.Furthermore,RE+BFR significantly increases D-dimer after 4 h.Patients with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.
基金funded by the National Insti-tutes of Health(No.R01 AR074234)AHA collaborative award(No.944227)the Gillian Reny Stepping Strong Center for Trauma Inno-vation at Brigham and Women's Hospital.
文摘Ensuring a sufficient oxygen supply is pivotal for the success of bioprinting applications since it fosters tissue integration and natural regeneration.Variation in oxygen concentration among diverse tissues necessitates the precise recreation of tissue-specific oxygen levels in imprinted constructs to support the survival of targeted cells.Although oxygen-releasing biomaterials,such as oxygen-generating microparticles(OMPs),have shown promise for enhancing the oxygen supply of microenvironments in injured tissues,whether this approach is scalable for large tissues and whether tissue-specific bioinks with varying OMP concentrations remain printable remain unknown.This study addresses this critical gap by introducing an innovative class of engineered oxygenated bioinks that combine colloidal-based microgels with OMPs.We report that incorporating nanosized calcium peroxide(nCaO_(2))and manganese oxide nanosheets(nMnO_(2))into hydrophobic polymeric microparticles enables precise modulation of oxygen release while controlling hydrogen peroxide release.Moreover,the fabrication of oxygenating and cytocompatible colloidal gels is achieved using an aqueous two-phase system.This study thoroughly evaluates the fundamental characteristics of the resulting bioink,including its rheological behaviors,printability,shape fidelity,mechanical properties,and oxygen release properties.Moreover,this study demonstrates the macroscopic scalability and cytocompatibility of printed constructs produced via cell-laden oxygenating colloidal bioinks.By showcasing the effectiveness of extrusion-based bioprinting,this study underscores how it can be used to fabricate biomimetic tissues,indicating its potential for new applications.The findings presented here advance the bioprinting field by achieving scalability with both high cell viability and the possibility of mimicking specifically oxygenated tissues.This work thereby offers a promising avenue for the development of functional tissues with enhanced physiological relevance.
文摘Dear editor:We sincerely thank Matthew J.Clarkson for his insightful commentary1 on our recent publication in the Journal of Sport and Health Science.2 Clarkson's pioneering work in the development and application of blood flow restriction (BFR) exercise protocols has undeniably laid the groundwork for subsequent investigations in this field,including our own.(3-6)His commentary not only highlights the relevance and timeliness of our study but also offers valuable perspectives on refining safety considerations for intradialytic BFR exercise among hemodialysis patients.
文摘Soymilk is one of the most available beverages, an alternative to dairy milk and is recognized for its nutritional value. The nutritional quality, the presence of anti-nutritional factors, isoflavones and sensory acceptability of soymilk depended on the soybean variety as well as the processing conditions. The soymilks from conventional and specialty Brazilian soybean cultivars were compared regarding the composition and consumer acceptance. There were significant differences on the protein, oil, sugars, isoflavones, presence of anti-nutritional factors (phytate and trypsin inhibitor activity) and NSI (nitrogen solubility index) among cultivars and soymilks and for sensory acceptance of soymilks. The preference mapping and cluster analysis identified three different segments of consumers. The soymilk from the conventional cultivar BRS284 achieved higher and similar acceptance score for the three consumer’s segments while the lipoxygenase free cultivars (BRS213 and BRS257) and specialty cultivar BRS216 showed higher score for two segments of consumers. The sensory evaluation of soymilk from different soybean cultivars could improve consumer uptake.
文摘Coffee is highly appreciated as stimulant. Brazil is the first producer and second consumer in the world. Flower evocation triggered by environmental signals is essential for adaptability and productivity, and despite that it is neglected and barely considered as a part of the reproductive cycle. Aiming to review molecular mechanisms producing phenological responses observed in the fields, orthologs to A. thaliana CO, FLC/FLM, FLT, SOC and VRN genes were identified in silico for C. arabica and its ancestors C. canephora and C. eugenioides. Protein structures and conserved domains, regulatory elements in promoters, and the related literature in both genera were accessed and compared. Hypotheses regarding Coffea spp. orthologs responsiveness to light and temperature signals at the tropics are proposed. Preliminary analysis of phenological data taken from early, intermediary and late C. arabica plants are included to illustrate the diversity regarding flower bud emission, which quite certainly is defined during flower evocation.
文摘“Pinhão”, the seed of Araucaria angustifolia, is an important food, being part of the eating habits of Indigenous communities. In this study, we evaluated the oligosaccharide content, resistant starch and the growth of probiotic bacteria. GF4 (1-fructofuranosylnystose) was the main fructo-oligosaccharides found, in higher contents compared to other food sources. Maltooligosaccharides (MOS) represented the main part of the oligosaccharides profile of Brazilian pine seeds. In descending order of importance was maltoheptaose (G7), maltohexose (G6) and maltotriose (G3). The starches from the variety Sanct josephi presented the highest amount of resistant starch that could stimulate probiotic strains, mainly B. breve and L. plantarum, and may have a prebiotic effect, potentially promoting health benefits. This study advances the understanding of the chemical composition of the main portion of the “pinhão” enhancing awareness of its potential as a healthy food source, contributing to different uses and indirectly with the species preservation.
基金the National council for scientific and technological development(CNPq)and Higher Education Personnel Improvement Coordination(CAPES)。
文摘Needle chlorosis(NC)in Pinus taeda L.systems in Brazil becomes more frequent after second and third harvest rotation cycles.In a study to identify factors contributing to yellowing needle chorosis(YNC),trees were grown in soils originating from contrasting parent materials,and soils and needles(whole,green and chlorotic portions)from 1-and 2-year-old branches and the first and second needle flush release at four sites with YNC on P.taeda were analyzed for various elements and properties.All soils had very low base levels(Ca^(2+),Mg^(2+)and K^(+))and P,suggesting a possible lack of multiple elements.YNC symptoms started at needle tips,then extended toward the needle base with time.First flush needles had longer portions with YNC than second flush needles did.Needles from the lower crown also had more symptoms along their length than those higher in the canopy.Symptoms were similar to those reported for Mg.In chlorotic portions,Mg and Ca concentrations were well below critical values;in particular,Mg levels were only one third of the critical value of 0.3 g kg^(-1).Collectively,results suggest that Mg deficiency is the primary reason for NC of P.taeda in various parent soils in Brazil.
基金supported by the Coordenacao de Aperfeicoamento de Pessoal de Nível Superior–Brasil (CAPES)–Finance Code 001the Postgraduate Programme in Forest Engineering of the Federal University of Lavras (PPGEF/UFLA)and Group of Optimization and Planning (GOPLAN/UFLA/LEMAF-Forest Management Research Lab)。
文摘Selective logging is well-recognized as an effective practice in sustainable forest management.However,the ecological efficiency or resilience of the residual stand is often in doubt.Recovery time depends on operational variables,diversity,and forest structure.Selective logging is excellent but is open to changes.This may be resolved by mathematical programming and this study integrates the economic-ecological aspects in multi-objective function by applying two evolutionary algorithms.The function maximizes remaining stand diversity,merchantable logs,and the inverse of distance between trees for harvesting and log landings points.The Brazilian rainforest database(566 trees)was used to simulate our 216-ha model.The log landing design has a maximum volume limit of 500 m3.The nondominated sorting genetic algorithm was applied to solve the main optimization problem.In parallel,a sub-problem(p-facility allocation)was solved for landing allocation by a genetic algorithm.Pareto frontier analysis was applied to distinguish the gradientsα-economic,β-ecological,andγ-equilibrium.As expected,the solutions have high diameter changes in the residual stand(average removal of approximately 16 m^(3) ha^(-1)).All solutions showed a grouping of trees selected for harvesting,although there was no formation of large clearings(percentage of canopy removal<7%,with an average of 2.5 ind ha^(-1)).There were no differences in floristic composition by preferentially selecting species with greater frequency in the initial stand for harvesting.This implies a lower impact on the demographic rates of the remaining stand.The methodology should support projects of reduced impact logging by using spatial-diversity information to guide better practices in tropical forests.
基金CMPC,Fapergs(Innovation and Technology Network of Low Carbon Agriculture and adapted to Climate Change in Rio Grande do Sul State)CNPq+3 种基金RCGI(Research Centre for Greenhouse Gas Innovation—USP)FAPESPShell BrasilANP。
文摘Eucalyptus harvest residues are attractive energy production resources for the forestry industry.However,their removal can have adverse impacts on soil quality and forest productivity,especially in sandy soils.In this study,we assessed the effects of Eucalyptus harvest residue managements with variable intensity on forest productivity and on physical,chemical,and biological indicators of the soil quality.The experiment was conducted in a Quartzipsamment(33 g kg-1clay)planted with Eucalyptus saligna in Barra do Ribeiro in southern Brazil.Before the Eucalyptus was planted,residues from the previous rotation were subjected to five different management treatments:(1)FRM,in which all forest residues(bark,branches,leaves,and litter)were allowed to remain on the soil and only trunk wood was removed;(2)FRMB,in which was identical to FRM except that bark was also removed;(3)FRMBr,in which only trunk wood and branches were removed;(4)FRR,which involved removing all types of residues(bark,branches,leaves,and litter);and,(5)FRRs,in which all forest residues from the previous rotation were removed,and leaves and branches from the new plantation were prevented from falling onto the soil surface using a shade net.Six years after planting,soil samples were collected at four different depths(0-2.5,2.5-5,5-10,and 10-20 cm)to determine 17 soil chemical,physical,and biological indicators.The results were combined into a soil quality index(SQI)using the principal component analysis approach.The SQI reduced by 30%,in the 0-20 cm layer,due to removal of harvest residues from the previous rotation,and collection of litter before it falls on the ground.The main drivers of SQI reduction were the principal components associated with soil organic matter and biological activity.Furthermore,the SQI was positively linearly related to tree height at P<0.01 and to tree diameter at breast height at P=0.07.The adverse impact on soil quality and forest productivity in our study indicates that removal of Eucalyptus harvest residues from sandy soils should be avoided.
基金Project supported by the Brazilian Corporation for Agricultural Research (No.02.03.01.01.04) the Usina Triunfo(Alagoas State), Brazil.
文摘An important factor for the sustainability of soils highly susceptible to degradation is the use of monitoring tools that promptly and realistically reflect changes imposed on soil by different cropping systems. To select soil quality indicator variables in sugarcane (Saccharum officinarum L.) production areas that fulfill the criteria of sensitivity to management practices and between-season consistency in the management discrimination, ten composite soil samples (0–10 cm) were collected in July 2005 (rainy season) and again in March 2006 (dry season) from areas under cultivation of organic sugarcane (OS), green sugarcane (GS), burned sugarcane (BS) and from an adjacent native forest (NF) area at Usina Triunfo, Boca da Mata, Alagoas, Brazil. Microbial biomass-C (MBC), total organic C (TOC), soil enzyme activity expressed as the rate of fluorescein diacetate (FDA) hydrolysis, mean weight diameter of water-stable soil aggregates (MWD), and percentage of water-stable macroaggregates (PWSA) were analyzed. Although MBC and TOC were higher in NF than in the cultivated areas, no differences were observed in these C pools between the three sugarcane systems. The response of FDA to the site management was dependent on the sampling time. In the rainy period, the activity followed the order: NF > OS > GS > BS, whereas in the dry season, only NF differed from the other treatments. Irrespective of the sampling time, MWD and PWSA decreased in the order NF > OS = GS > BS. The variables MWD and PWSA are quite sensitive for discriminating between site management histories regardless the sampling season.
基金the National Council for Scientific and Technological Development (CNPq)Foundation for Research Support of the State of Goiás for their support
文摘Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops(cultivated in the offseason) in the soybean-upland rice rotation(cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4 × 2 with six replications. Treatments were composed by four cover crops: fallow, millet(Pennisetum glaucum) + Crotalaria ochroleuca, millet + pigeon pea(Cajanus cajans), and millet + pigeon pea + Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice(Oryza sativa)or soybean(Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced p H, Al and H + Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet + pigeon pea and millet + pigeon pea + U. ruziziensis improved soil physical properties in relation to fallow,especially in the 0–0.10 m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover crops.Soybean grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops.
文摘Legume nodulation by rhizobia can supply crops with nitrogen and reduce environmental impacts caused by chemical fertilization. The soybean crop in Brazil is an impressive example of how biological N2 fixation can be employed with a plant species of high economic value. However, the development of more productive cultivars, along with the increasing global climatic changes demand agricultural practices to become more productive and yet more environmentally friendly. Plant growth-promoting rhizobacteria (PGPR) are highly beneficial to agriculture worldwide, acting in plant nutrition, protection, and growth stimulation. Azospirillum is, certainly, the most employed PGPR in the world, but little is known about its interaction with rhizobia, when both are applied to legume seeds. We have evaluated the co-inoculation of bradyrhizobia and azospirilla on soybean seeds under different soil and climate conditions in Brazil. Our results demonstrated that co-inoculation is efficient and beneficial to the crop, and promotes yield increases without adding any chemical N fertilizers even in soils where established populations of soybean bradyrhizobia exist. The strategy of co-inoculation thus represents a new biotechnological tool to improve soybean yield without adding any chemical N fertilizers, thus contributing to current practices of sustainability in agriculture.
基金This work was supported by‘Coordenação de Aperfeiçoamento de Pessoal de Nível Superior’(CAPES,Brazil),‘Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq,Brazil,Proc.475440/2004-8,GP research fellowship 311361/2009-9),‘Fundação de AmparoàPesquisa do Estado do Rio Grande do Sul’(FAPERGS,Brazil,Proc.04/1184.6)and Embrapa(Brazil).
文摘The Dof(DNA-binding with one finger)protein family spans a group of plant transcription factors involved in the regulation of several functions,such as plant responses to stress,hormones and light,phytochrome signaling and seed germination.Here we describe the Dof-like gene family in grapevine(Vitis vinifera L.),which consists of 25 genes coding for Dof.An extensive in silico characterization of the VviDofL gene family was performed.Additionally,the expression of the entire gene family was assessed in 54 grapevine tissues and organs using an integrated approach with microarray(cv Corvina)and real-time PCR(cv Pinot Noir)analyses.The phylogenetic analysis comparing grapevine sequences with those of Arabidopsis,tomato,poplar and already described Dof genes in other species allowed us to identify several duplicated genes.The diversification of grapevine DofL genes during evolution likely resulted in a broader range of biological roles.Furthermore,distinct expression patterns were identified between samples analyzed,corroborating such hypothesis.Our expression results indicate that several VviDofL genes perform their functional roles mainly during flower,berry and seed development,highlighting their importance for grapevine growth and production.The identification of similar expression profiles between both approaches strongly suggests that these genes have important regulatory roles that are evolutionally conserved between grapevine cvs Corvina and Pinot Noir.
基金financed by CAPES (Coordenao de Aperfeioamento de Pessoal de Nível Superior)
文摘A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grand& plantations in the semiarid region ( 15° 09′ S 43° 49′ W) in the north of the State of Minas Gerais in Brazil. Results show that the total above-ground biomass (dry matter) was 33.6 Mg.ha^-1 for E. camaldulensis and 53.1 Mg·ha^-1 for E. grandis. The biomass of the stem wood, leaves, branches, and stein bark for E. camaldulens accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively (Table 2); meanwhile a similar partition of the total above-ground biomass was also found for E. grand&. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%, 0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk (bark and wood), nutrient accumulation in general was lower. Nutrient content of E. grand& presented little variation compared with that orE. camaJd^llensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of nutrients, especially in E. grand&. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this semi-arid region. The two species showed mycotrophy.
文摘Genetic transformation is becoming routine for engineering specific traits in important clones of recalcitrant species such as Eucalyptus;however,the efficiency is still low for most species,so many researchers still use seeds instead of clones as initial explants.This work aimed to develop a genetic transformation protocol,based on a highly efficient in vitro organogenesis protocol,for an Eucalyptus urophylla clone selected in our breeding program.Plant growth regulators were evaluated for indirect organogenesis and rooting.In a two-step protocol,the combination of callus induction media supplemented with 0.5 μM thidiazuron+0.5 μM naphthaleneacetic acid(NAA)and shoot induction media supplemented with 5.0 μM benzylaminopurine+1.0 lM NAA allowed up to 85.6%shoot formation with more shoots per explants when compared with other concentrations.Transgenic plants expressing the uidA gene were obtained using Agrobacterium tumefaciens and selected for kanamycin resistance.A RAPD analysis was used to check for somaclonal variation.In tests using 11 RAPD primers,we did not observe somaclonal variation in the in vitro stages evaluated.
文摘A longer stem elongation phase (from the terminal spikelet-TS to the anthesis-ANT phases) increases grain production due to an increase in spikelet fertility. However, the mechanism behind the greater number of fertile flowers that occur when the duration of stem elongation is modified by photoperiod and vernalization is not fully understood. The goal of this study was to investigate the effect of combinations of photoperiod and vernalization on the duration of stem elongation and spikelet fertility in wheat. Thus, a greenhouse experiment was performed by subjecting 13 wheat genotypes to two vernalization regimes (V0—non-vernalized plants and V40—plants with 40 vernalization days) and to two photoperiod regimes (NP—natural and NP + 6—photoperiod extended by six hours), during the stem elongation phase. The natural photoperiod increased the spikelet fertility of eight cultivars without a corresponding increased duration of the TS-ANT phase, suggesting the existence of a direct effect of photoperiod on increased spikelet fertility. Vernalization increased the duration of the TS-ANT phase, without influencing spikelet fertility. There was genetic variability in the responses to photoperiod and vernalization.
文摘The conversion of sugarcane lignocellulosic biomass into fuels,chemicals and high-value materials using the biochemical pathway is considered the most sustainable alternative for the implementation of future biorefineries.Actually,the first large-scale cellulosic ethanol plants that have started operating worldwide apply the enzymatic hydrolysis process to convert biomass into simple sugars that are fermented to ethanol by yeasts.However,several technological challenges still need to be addressed in order to obtain commercially competitive products.This review describes current challenges and perspectives regarding the enzymatic hydrolysis step for processing sugarcane lignocellulosic biomass within the biorefinery.Recent developments in terms of process configuration strategies and opportunities for the implementation of a sugarcane biorefinery,in which the production of ethanol is integrated into the production of high-value products such as enzymes and nanocellulose,are discussed in view of the demands of the current bioeconomy.