Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the envi...Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.展开更多
Shrimps of the genus Synalpheus(Caridea)are commonly found in subtropical and tropical marine habitats around the world.The present work aims to provide the first description of the reproductive system of this genus u...Shrimps of the genus Synalpheus(Caridea)are commonly found in subtropical and tropical marine habitats around the world.The present work aims to provide the first description of the reproductive system of this genus using histological,histochemical,and morphological perspectives to elucidate the gonochoric or hermaphrodite sexual system in this genus.Males have a slender and very translucent reproductive system that is challenging to observe.The entire cephalothorax was histologically sectioned to ensure that all regions of the reproductive system could be identified.This non-gambarelloides group shows a gonochoric condition.The caridean pattern of the reproductive system was observed where the male has a pair of testes and a pair of very thin vasa deferentia,ending at the opening of the gonopore.Spermatophore structure is absent,without any layers surrounding the spermatozoa that are aggregated in a sperm mass.In females,the reproductive system consists of a pair of ovaries that extend to the end of the pleon.The extension of the ovary has a particular pattern compared to other caridean shrimps.Here,we hypothesize that males invest energy on somatic morphological structures to protect the host and female,using the larger pistol-like cheliped,while females invest energy in reproduction since all the members of this group are typical"pair-bond"examples.The observed pattern of the reproductive male morphology could also be evidence of a possible synapomorphy for this genus within theinfraorder.展开更多
A purpose of dietary assessment is to evaluate the dietary intake of a group or a population. In Brazil few studies have been carried out to identify dietary intake of older people population. Then, the aim of this wo...A purpose of dietary assessment is to evaluate the dietary intake of a group or a population. In Brazil few studies have been carried out to identify dietary intake of older people population. Then, the aim of this work is to estimate the distribution as well as estimate the prevalence of inadequacy of the usual intake in a representative sample of older population from Botucatu city, S?o Paulo, applying the NCI method. A sample of 365 older was used and some instruments to evaluate quality of life, activities of daily living and instrumental of daily living were applied as well as three 24-hour recalls. Data from the recalls were transformed in consumption of macro and micronutrients using NDSR software and were analyzed using NCI method in order to estimate the inadequacy prevalence. The energy and macronutrients intake of the studied population agree with their needs, however, the consumption of minerals and vitamins were below the recommendation even after including the covariates. This can reflects a monotone intake that is characteristic of this age and this inadequateness can be a serious public health problem that can carry on development of chronic diseases. Also, it is important to highlight that NCI method provides a good estimate of the usual intake.展开更多
Theβ-glucosidase gene from Aspergillus nidulans FGSC A4 was cloned and overexpressed in the A.nidulans A773.The resulting purifiedβ-glucosidase,named AnGH3,is a monomeric enzyme with a molecular weight of approximat...Theβ-glucosidase gene from Aspergillus nidulans FGSC A4 was cloned and overexpressed in the A.nidulans A773.The resulting purifiedβ-glucosidase,named AnGH3,is a monomeric enzyme with a molecular weight of approximately 80 kDa,as confirmed by SDS-PAGE.Circular dichroism further validated its unique canonical barrel fold(β/α),a feature also observed in the 3D homology model of AnGH3.The most striking aspect of this recombinant enzyme is its robustness,as it retained 100%activity after 24 h of incubation at 45 and 50ºC and pH 6.0.Even at 55°C,it maintained 72%of its enzymatic activity after 6 h of incubation at the same pH.The kinetic parameters Vmax,KM,and Kcat/KM forρ-nitrophenyl-β-D-glucopyranoside(ρNPG)and cellobiose were also determined.UsingρNPG,the enzyme demonstrated a Vmax of 212 U mg−1,KM of 0.0607 mmol L−1,and Kcat/KM of 4521 mmol L−1 s−1 when incubated at pH 6.0 and 65°C.The KM,Vmax,and Kcat/KM using cellobiose were 2.7 mmol L−1,57 U mg−1,and 27 mmol-1 s−1,respectively.AnGH3 activity was significantly enhanced by xylose and ethanol at concentrations up to 1.5 mol L−1 and 25%,respectively.Even in challenging conditions,at 65°C and pH 6.0,the enzyme maintained its activity,retaining 100%and 70%of its initial activity in the presence of 200 mmol L−1 furfural and 5-hydroxymethylfurfural(HMF),respectively.The potential of this enzyme was further demonstrated by its application in the saccharification of the forage grass Panicum maximum,where it led to a 48%increase in glucose release after 24 h.These unique characteristics,including high catalytic performance,good thermal stability in hydrolysis temperature,and tolerance to elevated concentrations of ethanol,D-xylose,furfural,and HMF,position this recombinant enzyme as a promising tool in the hydrolysis of lignocellulosic biomass as part of an efficient multi-enzyme cocktail,thereby opening new avenues in the field of biotechnology and enzymology.展开更多
Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limi...Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limited to management of the symptoms. The concept of a dysregulated gut-brain axis has been adopted as a suitable model for the disorder. The gut microbiome may play an important role in the onset and exacerbation of symptoms in the disorder and has been extensively studied in this context. Although a causal role cannot yet be inferred from the clinical studies which have attempted to characterise the gut microbiota in IBS, they do confirm alterations in both community stability and diversity. Moreover, it has been reliably demonstrated that manipulation of the microbiota can influence the key symptoms, including abdominal pain and bowel habit, and other prominent features of IBS. A variety of strategies have been taken to study these interactions, including probiotics, antibiotics, faecal transplantations and the use of germ-free animals. There are clear mechanisms through which the microbiota can produce these effects, both humoral and neural. Taken together, these findings firmly establish the microbiota as a critical node in the gut-brain axis and one which is amenable to therapeutic interventions.展开更多
The contamination of soils by polycyclic aromatic hydrocarbons （PAHs） is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bi...The contamination of soils by polycyclic aromatic hydrocarbons （PAHs） is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bioremediation systems may be constrained by low contaminant bioavailability due to limited aqueous solubility or a large magnitude of sorption. The objective of this research was to evaluate the effect of methyl-β-cyclodextrin （MCD） on bioaugmentation by Paracoccus sp. strain HPD-2 of an aged PAH-contaminated soil. When 10% （W/W） MCD amendment was combined with bioaugmentation by the PAH-degrading bacterium Paracoccus sp. strain HPD-2, the percentage degradation of total PAHs was significantly enhanced up to 34.8%. Higher counts of culturable PAH- degrading bacteria and higher soil dehydrogenase and soil polyphenol oxidase activities were observed in 10% （W/W） MCD-assisted bioaugmentation soil. This MCD-assisted bioaugmentation strategy showed significant increases （p 〈 0.05） in the average well color development （AWCD） obtained by the BIOLOG Eco plate assay, Shannon-Weaver index （H） and Simpson index （λ） compared with the controls, implying that this strategy at least partially restored the microbiological functioning of the PAH-contaminated soil. The results suggest that MCD-aided bioaugmentation by Paracoccus sp. strain HPD-2 may be a promising practical bioremediation strategy for aged PAH-contaminated soils.展开更多
Spinal cord injury(SCI) research is a very complex field lending to why reviews of SCI literatures can be beneficial to current and future researchers. This review focuses on recent articles regarding potential modali...Spinal cord injury(SCI) research is a very complex field lending to why reviews of SCI literatures can be beneficial to current and future researchers. This review focuses on recent articles regarding potential modalities for the treatment and management of SCI. The modalities were broken down into four categories: neuroprotectionpharmacologic, neuroprotection-non-pharmacologic, neuroregeneration-pharmacologic, neuroregeneration-non-pharmacologic. Peer-reviewed articles were found using Pub Med with search terms: "spinal cord injury", "spinal cord injury neuroregeneration", "olfactory ensheathing cells spinal cord injury", "rho-rock inhibitors spinal cord injury", "neural stem cell", "scaffold", "neural stem cell transplantation", "exosomes and SCI", "epidural stimulation SCI", "brain-computer interfaces and SCI". Most recent articles spanning two years were chosen for their relevance to the categories of SCI management and treatment. There has been a plethora of pre-clinical studies completed with their results being difficult to replicate in clinical studies. Therefore, scientists should focus on understanding and applying the results of previous research to develop more efficacious preclinical studies and clinical trials.展开更多
Neuroprotection and neuroregeneration are two of the most promising disease-modifying ther- apies for the incurable and widespread Parkinson＇s disease. In Parkinson＇s disease, progressive degeneration of nigrostriat...Neuroprotection and neuroregeneration are two of the most promising disease-modifying ther- apies for the incurable and widespread Parkinson＇s disease. In Parkinson＇s disease, progressive degeneration of nigrostriatal dopaminergic neurons causes debilitating motor symptoms. Neurotrophic factors play important regulatory roles in the development, survival and maintenance of specific neuronal populations. These factors have the potential to slow down, halt or reverse the loss of nigrostriatal dopaminergic neurons in Parkinsoffs disease. Several neurotrophic fac- tors have been investigated in this regard. This review article discusses the neurodevelopmental roles and therapeutic potential of three dopaminergic neurotrophic factors： glial cell line-derived neurotrophic factor, neurturin and growth/differentiation factor 5.展开更多
Single phytotoxicity of two representative phthalate esters(PAEs),di-n-butyl phthalate(DnBP)and bis(2-ethylhexyl)phthalate(DEHP),was tested in mung bean(Vigna radiata)seedlings germinated for 72 h in soils spiked with...Single phytotoxicity of two representative phthalate esters(PAEs),di-n-butyl phthalate(DnBP)and bis(2-ethylhexyl)phthalate(DEHP),was tested in mung bean(Vigna radiata)seedlings germinated for 72 h in soils spiked with varying concentrations(0-500 mg kg^(-1)soil)of DnBP or DEHP.PAEs added at up to 500 mg kg^(-1)soil exerted no significant effect on germination but both pollutants significantly inhibited root elongation(P<0.01),DEHP inhibited shoot elongation(P<0.01)and DnBP depressed biomass on a fresh weight basis(P<0.05).Seedling shoot and root malondialdehyde(MDA)contents tended to be stimulated by DnBP but inhibited by DEHP.However,increases in superoxide dismutase,peroxidase,ascorbate peroxidase and polyphenol oxidase activities,as well as glutathione(GSH)content,were induced at higher concentrations(e.g.,20 mg kg^(-1))of both compounds.Accumulation of proline in both roots and shoots and the storage compounds,such as free amino acids and total soluble sugars,in whole plant was induced under the stress exerted by both PAEs.The general responses of mung bean seedlings indicated higher toxicity of DnBP than DEHP on primary growth,during which root elongation was a more responsive index.MDA and GSH were more sensitive parameters in the roots than in the shoots and they might be recommended as physiologically sensitive parameters to assess the toxicity of PAE compounds in soils in future long-term studies.展开更多
Diphenylarsinic acid （DPAA） is formed during the leakage of aromatic arsenic chemical weapons in soils, is persistent in nature, and results in arsenic contamination in the field. The adsorption and desorption chara...Diphenylarsinic acid （DPAA） is formed during the leakage of aromatic arsenic chemical weapons in soils, is persistent in nature, and results in arsenic contamination in the field. The adsorption and desorption characteristics of DPAA were investigated in two typical Chinese soils, an Acrisol （a variable-charge soil） and a Phaeozem （a constant-charge soil）. Their thermodynamics and some of the factors influencing them （i.e., initial pH value, ionic strength and phosphate） were also evaluated using the batch method in order to understand the environmental fate of DPAA in soils. The results indicate that Acrisol had a stronger adsorption capacity for DPAA than Phaeozem. Soil DPAA adsorption was a spontaneous and endothermic process and the amount of DPAA adsorbed was affected significantly by variation in soil pH and phosphate. In contrast, soil organic matter and ionic strength had no significant effect on adsorption. This suggests that DPAA adsorption may be due to specific adsorption on soil mineral surfaces. Therefore, monitoring the fate of DPAA in soils is recommended in areas contaminated by leakage from chemical weapons.展开更多
Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.frag...Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.展开更多
Excessive amounts of nitrate have accumulated in many soils on the North China Plain due to the large amounts of chemical N fertilizers or manures used in combination with low carbon inputs. We investigated the potent...Excessive amounts of nitrate have accumulated in many soils on the North China Plain due to the large amounts of chemical N fertilizers or manures used in combination with low carbon inputs. We investigated the potential of different carbon substrates added to transform soil nitrate into soil organic N （SON）. A 56-d laboratory incubation experiment using the 15N tracer （K15NO3） technique was carried out to elucidate the proportion of SON derived from accumulated soil nitrate following amendment with glucose or maize straw at controlled soil temperature and moisture. The dynamics and isotopic abundance of mineral N （NO3 and NH4＋） and SON and greenhouse gas （N20 and CO2） emissions during the incubation were investigated. Although carbon amendments markedly stimulated transformation of nitrate to newly formed SON, this was only a substitution effect of the newly formed SON with native SON because SON at the end of the incubation period was not significantly different （P 〉 0.05） from that in control soil without added C. At the end of the incubation period, amendment with glucose, a readily available C source, increased nitrate immobilization by 2.65 times and total N20-N emission by 33.7 times, as compared with maize straw amendment. Moreover, the differences in SON and total N20-N emission between the treatments with glucose and maize straw were significant （P 〈 0.05）. However, the total N20-N emission in the straw treatment was not significantly （P ~ 0.05） greater than that in the control. Straw amendment may be a potential option in agricultural practice for transformation of nitrate N to SON and minimization of N20 emitted as well as restriction of NO3-N leaching.展开更多
Although the effect of animal and diet factors on enteric methane （CH4） emissions from confined cattle has been extensively examined, less data is available regarding CH4 emissions from grazing young cattle. A study...Although the effect of animal and diet factors on enteric methane （CH4） emissions from confined cattle has been extensively examined, less data is available regarding CH4 emissions from grazing young cattle. A study was undertaken to evaluate the effect of the physiological state of Holstein-Friesian heifers on their enteric CH4 emissions while grazing a perennial ryegrass sward. Two experiments were conducted： Experiment 1 ran from May 2011 for 11 weeks and Experiment 2 ran from August 2011 for 10 weeks. In each experiment, Holstein-Friesian heifers were divided into three treatment groups （12 animals/group） consisting of calves, yearling heifers, and in-calf heifers （average ages： 8.5, 14.5, and 20.5 months, respectively）. Methane emissions were estimated for each animal in the final week of each experiment using the sulfur hexafluoride tracer technique. Dry matter （DM） intake was estimated using the calculated metabolizable energy （ME） requirement divided by the ME concentration in the grazed grass. As expected, live weight increased with increasing animal age （P 〈 0.001）; however, there was no difference in live weight gain among the three groups in Experiment 1, although in Experiment 2, this variable decreased with increasing animal age （P 〈 0.001 ）. In Experiment 1, yearling heifers had the highest CH4 emissions （g·d^-1） and in-calf heifers produced more than calves （P 〈 0.001 ）. When expressed as CH4 emissions per unit of live weight, DM intake, and gross energy （GE） intake, yearling heifers had higher emission rates than calves and in-calf heifers （P 〈 0.001）. However, the effects on CH4 emissions were different in Experiment 2, in which CH, emissions （g·d^-1） increased linearly with increasing animal age （P 〈 0.001）, although the difference between yearling and in-calf heifers was not significant. The CH4/live weight ratio was lower in in-calf heifers than in the other two groups （P 〈 0.001 ）, while CH4 energy output as a proportion of GE intake was lower in calves than in yearling and in-calf heifers （P 〈 0.05）. All data were then pooled and used to develop prediction equations for CH4 emissions. All relationships are significant （P 〈 0.001）, with R2 values ranging from 0.630 to 0.682. These models indicate that CH4 emissions could be increased by 0.252 g.d-1 with an increase of I kg live weight or by 14.9 g·d^-1 with an increase of 1 kg·d^-1 of DM intake; or, the CH4 energy output could be increased by 0.046 MJ·d^-1 with an increase of 1 MJ·d^-1 of GE intake. These results provide an alternative approach for estimating CH4 emissions from grazine dairy heifers when actual CH, emission data are not available.展开更多
Atmospheric nitrogen (N) deposition has been poorly documented in northern China, an intensive agricultural and industrial region with large emissions of NHx and NOy. To quantify N deposition, total airborne N deposit...Atmospheric nitrogen (N) deposition has been poorly documented in northern China, an intensive agricultural and industrial region with large emissions of NHx and NOy. To quantify N deposition, total airborne N deposition was determined at three agricultural sites using a manual integrated total nitrogen input (ITNI) system during growth of winter wheat (Triticum aestivum L.) and Italian ryegrass (Lolium multiflorum Lam.) from September 2005 to May 2006. Total estimated N deposition averaged 54.9 and 43.2 kg N/hm2 across the three sites when wheat was grown to flowering and maturing, respectively. The average value was 50.2 kg N/hm2 when ryegrass was the indicator plant. Both indicator species gave similar total airborne N input results. The intermediate level of N supplied resulted in the highest N deposition, and the ratio of N acquired from deposition to total N content of the whole system decreased with increasing N supply to the roots. The contribution of atmospheric N to the total N content of the wheat and ryegrass sand culture systems ranged from 10% to 24%.展开更多
Pig and poultry production in China had experienced considerable changes from 1960 to 2010. The present study aimed to evaluate the effects of these changes on greenhouse gas emission inventeries （expressed as CO2 eq...Pig and poultry production in China had experienced considerable changes from 1960 to 2010. The present study aimed to evaluate the effects of these changes on greenhouse gas emission inventeries （expressed as CO2 equivalent） from these two sectors. The inventories included methane emissions from enteric fermentation, methane and nitrous oxide production from manure management. The greenhouse gas emissions from these sources in 2010 in pig sector were 17, 62 and 21%, respectively, and that in poultry sector （including chicken, duck, goose and others） were 1, 18 and 81%, respectively. Total CO2 equivalent increased from 1960 to 2010 in both pig （11 582 to 55564 Gg yr-1） and poultry （1 497 to 14 873 Gg yr-1） sectors. Within poultry sector, emissions from chicken, duck, goose and others accounted for 74, 15, 11 and 0.01% in 2010, respectively. However, during the last 50 years, these emissions continuously reduced when related to production of I kg of pork （8.01 to 1.14 kg kg-1）, poultry meat （1.19 to 0.37 kg kg-1） and egg （0.47 to 0.33 kg kg-1）, which is mainly associated with the continuous improvement in production efficiency in all management systems. These results provide benchmark information for Chinese authorities to develop appropriate policies and mitigation strategies to reduce greenhouse gas emissions from pig and poultry sectors.展开更多
Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to in...Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows.展开更多
Localized cell wall thickenings, so called papillae, are a common plant defense response to fungal attack at sites of penetration of the plant cell. The major constituent of papillae is callose, a (1,3)-β-glucan poly...Localized cell wall thickenings, so called papillae, are a common plant defense response to fungal attack at sites of penetration of the plant cell. The major constituent of papillae is callose, a (1,3)-β-glucan polymer, which contributes to slowing or blocking the invading fungal hyphae. In the model plant Arabidopsis thaliana, we could recently show that the overexpression of PMR4(POWDERY MILDEW RESITANT 4), which encodes a stress induced callose synthase, results in complete powdery mildew resistance. To evaluate if these findings are also transferable to monocot crops, we transiently expressed PMR4 under control of the 35S promoter in leaves of barley (Hordeum vulgare) seedlings, which were subsequently inoculated with the virulent powdery mildew Blumeria graminis f. sp. hordei. Fusion of the green fluorescent protein (GFP) to PMR4 allowed the identification of successfully transformed barley cells, which showed an increased penetration resistance to B. graminis compared to control cells that express only GFP.PMR4-GFP localized in a similar pattern at the site of attempted fungal penetration as observed inA. thaliana, which suggests that similar transport mechanisms of the callose synthase might exist in dicot and monocot plants.展开更多
We investigated 15N abundance （δ15N） of winter wheat （Triticum aestivum cv. Jinmai 1） plants and soil at different growth stages in a field with a 13-year fertilization history of urea and compost, to determine w...We investigated 15N abundance （δ15N） of winter wheat （Triticum aestivum cv. Jinmai 1） plants and soil at different growth stages in a field with a 13-year fertilization history of urea and compost, to determine whether or not the δ15N of plant parts can be used as an indicator of organic amendment with compost. Plant parts （roots, leaves, stems and grains） and soil were sampled at re-greening, jointing, grain filling and mature growth stages of winter wheat. There were significant differences between the urea and compost treatments in 815N of whole plants, plant parts and soil over the whole growing season. Determination of the δ15N of plant parts was more convenient than that of whole plant to distinguish between the application of organic amendment and synthetic N fertilizer.展开更多
Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly under...Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly understood.Using a 44-year grassland fertilization experiment,we investigated community shifts of active nitrifiers by DNA-based stable isotope probing(SIP)of field soils that received no fertilization(CK),high levels of organic cattle manure(HC),and chemical N fertilization(CF).Incubation of DNA-SIP microcosms showed significant nitrification activities in CF and HC soils,whereas no activity occurred in CK soils.The 44 years of inorganic N fertilization selected only 13C-ammonia-oxidizing bacteria(AOB),whereas cattle slurry applications created a niche in which both ammonia-oxidizing archaea(AOA)and AOB could be actively13C-labeled.Phylogenetic analysis indicated that Nitrosospira sp.62-like AOB dominated inorganically fertilized CF soils,while Nitrosospira sp.41-like AOB were abundant in organically fertilized HC soils.The 13C-AOA in HC soils were affiliated with the 29i4 lineage.The 13C-nitrite-oxidizing bacteria(NOB)were dominated by both Nitrospira-and Nitrobacter-like communities in CF soils,and the latter was overwhelmingly abundant in HC soils.The 13C-labeled nitrifying communities in SIP microcosms of CF and HC soils were largely similar to those predominant under field conditions.These results provide direct evidence for a strong selection of distinctly active nitrifiers after 44 years of different fertilization regimes in the field.Our findings imply that niche differentiation of nitrifying communities could be assessed as a net result of microbial adaption over 44 years to inorganic and organic N fertilization in the field,where distinct nitrifiers have been shaped by intensified anthropogenic N input.展开更多
基金funded by UK Research and Innovation(UKRI)doctoral training grant no:BB/T008776/1the Department of Agriculture,Environment and Rural Affairs(DAERA)by Trouw Nutrition and by John Thompsons and Sons Ltd.
文摘Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.
基金I.R.R.M.andA.L.C.were fundedby"Conselho Nacional de Desenvolvimento Cientifico e Tecnologico"(CNPQ grantPQ311034/2018-7)"Coordenacaode Aperfeicoamento deNivelSuperior-CAPES,Brazil(CAPES PRINT 88881.310767/2018-01,CAPES PROEX 23038.000802/2018-25)+2 种基金FJ.Z.would like to thank the laboratory support provided by the_Sao Paulo Research Foundation-FAPESP(JP#2005/04707-5 and Biota Intercrusta#2018/13685-5)CAPES-Ciencias do Mar II program(grant#1989/2014,23038.004309/2014-51)CNPq Research Scholarship(PQ2#309298-2020-2,PQ1D#308324/2023-4),and CNPq PPBio 2023/0723.
文摘Shrimps of the genus Synalpheus(Caridea)are commonly found in subtropical and tropical marine habitats around the world.The present work aims to provide the first description of the reproductive system of this genus using histological,histochemical,and morphological perspectives to elucidate the gonochoric or hermaphrodite sexual system in this genus.Males have a slender and very translucent reproductive system that is challenging to observe.The entire cephalothorax was histologically sectioned to ensure that all regions of the reproductive system could be identified.This non-gambarelloides group shows a gonochoric condition.The caridean pattern of the reproductive system was observed where the male has a pair of testes and a pair of very thin vasa deferentia,ending at the opening of the gonopore.Spermatophore structure is absent,without any layers surrounding the spermatozoa that are aggregated in a sperm mass.In females,the reproductive system consists of a pair of ovaries that extend to the end of the pleon.The extension of the ovary has a particular pattern compared to other caridean shrimps.Here,we hypothesize that males invest energy on somatic morphological structures to protect the host and female,using the larger pistol-like cheliped,while females invest energy in reproduction since all the members of this group are typical"pair-bond"examples.The observed pattern of the reproductive male morphology could also be evidence of a possible synapomorphy for this genus within theinfraorder.
基金thank to Sao Paulo Foundation Research(FAPESP-Process no.2008/10261-8)Na-tional Counsel of Technological and Scientific Devel-opment(CNPq Process no.301197/2011-3)for the fi-nancial support.
文摘A purpose of dietary assessment is to evaluate the dietary intake of a group or a population. In Brazil few studies have been carried out to identify dietary intake of older people population. Then, the aim of this work is to estimate the distribution as well as estimate the prevalence of inadequacy of the usual intake in a representative sample of older population from Botucatu city, S?o Paulo, applying the NCI method. A sample of 365 older was used and some instruments to evaluate quality of life, activities of daily living and instrumental of daily living were applied as well as three 24-hour recalls. Data from the recalls were transformed in consumption of macro and micronutrients using NDSR software and were analyzed using NCI method in order to estimate the inadequacy prevalence. The energy and macronutrients intake of the studied population agree with their needs, however, the consumption of minerals and vitamins were below the recommendation even after including the covariates. This can reflects a monotone intake that is characteristic of this age and this inadequateness can be a serious public health problem that can carry on development of chronic diseases. Also, it is important to highlight that NCI method provides a good estimate of the usual intake.
基金gratefully acknowledge the São Paulo Research Foundation(FAPESP)(Grant no:2018/07522-6,2021/06679-1,2022/00539-6,and 2023/01547-5FCT(POCI-01-0145-FEDER-032206)-transnational cooperation project EcoTech,Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq)(310340/2021-7)+6 种基金National Institute of Science and Technology of Bioethanol(INCT)(CNPq 465319/2014-9/FAPESP no:2014/50884-5)for financial supportResearch scholarships were granted to RCA by CNPq(Grant no:151187/2023-1)by FAPESP(Grant no:2023/09627-8)to DA by FAPESP(Grant no:2020/15510-8 and 2023/01338-7)to JCSS by CNPq(Grant no:384465/2023-4)FAPESP(Grant no:2019/21989-7)GSA by CAPES(Coordenação de Aperfeiçoamento de Pessoal de Nível Superior,Finance Code 001).
文摘Theβ-glucosidase gene from Aspergillus nidulans FGSC A4 was cloned and overexpressed in the A.nidulans A773.The resulting purifiedβ-glucosidase,named AnGH3,is a monomeric enzyme with a molecular weight of approximately 80 kDa,as confirmed by SDS-PAGE.Circular dichroism further validated its unique canonical barrel fold(β/α),a feature also observed in the 3D homology model of AnGH3.The most striking aspect of this recombinant enzyme is its robustness,as it retained 100%activity after 24 h of incubation at 45 and 50ºC and pH 6.0.Even at 55°C,it maintained 72%of its enzymatic activity after 6 h of incubation at the same pH.The kinetic parameters Vmax,KM,and Kcat/KM forρ-nitrophenyl-β-D-glucopyranoside(ρNPG)and cellobiose were also determined.UsingρNPG,the enzyme demonstrated a Vmax of 212 U mg−1,KM of 0.0607 mmol L−1,and Kcat/KM of 4521 mmol L−1 s−1 when incubated at pH 6.0 and 65°C.The KM,Vmax,and Kcat/KM using cellobiose were 2.7 mmol L−1,57 U mg−1,and 27 mmol-1 s−1,respectively.AnGH3 activity was significantly enhanced by xylose and ethanol at concentrations up to 1.5 mol L−1 and 25%,respectively.Even in challenging conditions,at 65°C and pH 6.0,the enzyme maintained its activity,retaining 100%and 70%of its initial activity in the presence of 200 mmol L−1 furfural and 5-hydroxymethylfurfural(HMF),respectively.The potential of this enzyme was further demonstrated by its application in the saccharification of the forage grass Panicum maximum,where it led to a 48%increase in glucose release after 24 h.These unique characteristics,including high catalytic performance,good thermal stability in hydrolysis temperature,and tolerance to elevated concentrations of ethanol,D-xylose,furfural,and HMF,position this recombinant enzyme as a promising tool in the hydrolysis of lignocellulosic biomass as part of an efficient multi-enzyme cocktail,thereby opening new avenues in the field of biotechnology and enzymology.
基金Supported by Science Foundation Ireland,No.SFI/12/RC/2272,No.02/CE/B124,No.07/CE/B1368Health Research Board No.HRA_POR/2011/23Brain and Behaviour Research Foundation No.20771
文摘Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limited to management of the symptoms. The concept of a dysregulated gut-brain axis has been adopted as a suitable model for the disorder. The gut microbiome may play an important role in the onset and exacerbation of symptoms in the disorder and has been extensively studied in this context. Although a causal role cannot yet be inferred from the clinical studies which have attempted to characterise the gut microbiota in IBS, they do confirm alterations in both community stability and diversity. Moreover, it has been reliably demonstrated that manipulation of the microbiota can influence the key symptoms, including abdominal pain and bowel habit, and other prominent features of IBS. A variety of strategies have been taken to study these interactions, including probiotics, antibiotics, faecal transplantations and the use of germ-free animals. There are clear mechanisms through which the microbiota can produce these effects, both humoral and neural. Taken together, these findings firmly establish the microbiota as a critical node in the gut-brain axis and one which is amenable to therapeutic interventions.
基金supported by the Natural Science Foundation of Jiangsu Province (No. BK2009016)the Chinese National Environmental Protection Special Funds for Scientific Research on Public Causes (No. 2010467016)the National High Technology Research and Development Program (863) of China (No. 2007AA061101)
文摘The contamination of soils by polycyclic aromatic hydrocarbons （PAHs） is a widespread environmental problem and the remediation of PAHs from these areas has been a major concern. The effectiveness of many in situ bioremediation systems may be constrained by low contaminant bioavailability due to limited aqueous solubility or a large magnitude of sorption. The objective of this research was to evaluate the effect of methyl-β-cyclodextrin （MCD） on bioaugmentation by Paracoccus sp. strain HPD-2 of an aged PAH-contaminated soil. When 10% （W/W） MCD amendment was combined with bioaugmentation by the PAH-degrading bacterium Paracoccus sp. strain HPD-2, the percentage degradation of total PAHs was significantly enhanced up to 34.8%. Higher counts of culturable PAH- degrading bacteria and higher soil dehydrogenase and soil polyphenol oxidase activities were observed in 10% （W/W） MCD-assisted bioaugmentation soil. This MCD-assisted bioaugmentation strategy showed significant increases （p 〈 0.05） in the average well color development （AWCD） obtained by the BIOLOG Eco plate assay, Shannon-Weaver index （H） and Simpson index （λ） compared with the controls, implying that this strategy at least partially restored the microbiological functioning of the PAH-contaminated soil. The results suggest that MCD-aided bioaugmentation by Paracoccus sp. strain HPD-2 may be a promising practical bioremediation strategy for aged PAH-contaminated soils.
文摘Spinal cord injury(SCI) research is a very complex field lending to why reviews of SCI literatures can be beneficial to current and future researchers. This review focuses on recent articles regarding potential modalities for the treatment and management of SCI. The modalities were broken down into four categories: neuroprotectionpharmacologic, neuroprotection-non-pharmacologic, neuroregeneration-pharmacologic, neuroregeneration-non-pharmacologic. Peer-reviewed articles were found using Pub Med with search terms: "spinal cord injury", "spinal cord injury neuroregeneration", "olfactory ensheathing cells spinal cord injury", "rho-rock inhibitors spinal cord injury", "neural stem cell", "scaffold", "neural stem cell transplantation", "exosomes and SCI", "epidural stimulation SCI", "brain-computer interfaces and SCI". Most recent articles spanning two years were chosen for their relevance to the categories of SCI management and treatment. There has been a plethora of pre-clinical studies completed with their results being difficult to replicate in clinical studies. Therefore, scientists should focus on understanding and applying the results of previous research to develop more efficacious preclinical studies and clinical trials.
基金supported by grants from the Irish Research Council(R13702 and R15897SVH/AS/G’OK)+3 种基金the Health Research Board of Ireland(HRA/2009/127GO’K/AS)Science Foundation Ireland(10/RFP/NES2786GO’K)
文摘Neuroprotection and neuroregeneration are two of the most promising disease-modifying ther- apies for the incurable and widespread Parkinson＇s disease. In Parkinson＇s disease, progressive degeneration of nigrostriatal dopaminergic neurons causes debilitating motor symptoms. Neurotrophic factors play important regulatory roles in the development, survival and maintenance of specific neuronal populations. These factors have the potential to slow down, halt or reverse the loss of nigrostriatal dopaminergic neurons in Parkinsoffs disease. Several neurotrophic fac- tors have been investigated in this regard. This review article discusses the neurodevelopmental roles and therapeutic potential of three dopaminergic neurotrophic factors： glial cell line-derived neurotrophic factor, neurturin and growth/differentiation factor 5.
基金Supported by the National Environmental Protection Special Fund for Scientific Research on Public Causes of China(Nos.201109018and 2010467016)
文摘Single phytotoxicity of two representative phthalate esters(PAEs),di-n-butyl phthalate(DnBP)and bis(2-ethylhexyl)phthalate(DEHP),was tested in mung bean(Vigna radiata)seedlings germinated for 72 h in soils spiked with varying concentrations(0-500 mg kg^(-1)soil)of DnBP or DEHP.PAEs added at up to 500 mg kg^(-1)soil exerted no significant effect on germination but both pollutants significantly inhibited root elongation(P<0.01),DEHP inhibited shoot elongation(P<0.01)and DnBP depressed biomass on a fresh weight basis(P<0.05).Seedling shoot and root malondialdehyde(MDA)contents tended to be stimulated by DnBP but inhibited by DEHP.However,increases in superoxide dismutase,peroxidase,ascorbate peroxidase and polyphenol oxidase activities,as well as glutathione(GSH)content,were induced at higher concentrations(e.g.,20 mg kg^(-1))of both compounds.Accumulation of proline in both roots and shoots and the storage compounds,such as free amino acids and total soluble sugars,in whole plant was induced under the stress exerted by both PAEs.The general responses of mung bean seedlings indicated higher toxicity of DnBP than DEHP on primary growth,during which root elongation was a more responsive index.MDA and GSH were more sensitive parameters in the roots than in the shoots and they might be recommended as physiologically sensitive parameters to assess the toxicity of PAE compounds in soils in future long-term studies.
基金supported by the National Natural Science Foundation of China (No. 41171248,40810180)the Ministry of Environmental Protection Special Funds for Scientific Research on Public Causes (No. 2010467016)
文摘Diphenylarsinic acid （DPAA） is formed during the leakage of aromatic arsenic chemical weapons in soils, is persistent in nature, and results in arsenic contamination in the field. The adsorption and desorption characteristics of DPAA were investigated in two typical Chinese soils, an Acrisol （a variable-charge soil） and a Phaeozem （a constant-charge soil）. Their thermodynamics and some of the factors influencing them （i.e., initial pH value, ionic strength and phosphate） were also evaluated using the batch method in order to understand the environmental fate of DPAA in soils. The results indicate that Acrisol had a stronger adsorption capacity for DPAA than Phaeozem. Soil DPAA adsorption was a spontaneous and endothermic process and the amount of DPAA adsorbed was affected significantly by variation in soil pH and phosphate. In contrast, soil organic matter and ionic strength had no significant effect on adsorption. This suggests that DPAA adsorption may be due to specific adsorption on soil mineral surfaces. Therefore, monitoring the fate of DPAA in soils is recommended in areas contaminated by leakage from chemical weapons.
基金This work was supported by research grants provided by the National Natural Science Foundation(31870695 and 31601785)the Project of Key Research and Development Plan(Modern Agriculture)in Jiangsu(BE2017375)+1 种基金the Selection and Breeding of Excellent Tree Species and Effective Cultivation Techniques(CX(16)1005)the Project of Osmanthus National Germplasm Bank,and the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions.
文摘Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.
基金Project supported by the National Natural Science Foundation of China(NSFC)(Nos.31172033 and 41101277)the National Science Basic Research Program of China(No.2007CB109308)+2 种基金the Foundation of the Chinese Ministry of Education for Ph.D.Work(No.20100008110004)the German Research Foundation (DFG)(No.IRTG 1070)the Innovation Group Grant of the National Natural Science Foundation of China(No.31121062)
文摘Excessive amounts of nitrate have accumulated in many soils on the North China Plain due to the large amounts of chemical N fertilizers or manures used in combination with low carbon inputs. We investigated the potential of different carbon substrates added to transform soil nitrate into soil organic N （SON）. A 56-d laboratory incubation experiment using the 15N tracer （K15NO3） technique was carried out to elucidate the proportion of SON derived from accumulated soil nitrate following amendment with glucose or maize straw at controlled soil temperature and moisture. The dynamics and isotopic abundance of mineral N （NO3 and NH4＋） and SON and greenhouse gas （N20 and CO2） emissions during the incubation were investigated. Although carbon amendments markedly stimulated transformation of nitrate to newly formed SON, this was only a substitution effect of the newly formed SON with native SON because SON at the end of the incubation period was not significantly different （P 〉 0.05） from that in control soil without added C. At the end of the incubation period, amendment with glucose, a readily available C source, increased nitrate immobilization by 2.65 times and total N20-N emission by 33.7 times, as compared with maize straw amendment. Moreover, the differences in SON and total N20-N emission between the treatments with glucose and maize straw were significant （P 〈 0.05）. However, the total N20-N emission in the straw treatment was not significantly （P ~ 0.05） greater than that in the control. Straw amendment may be a potential option in agricultural practice for transformation of nitrate N to SON and minimization of N20 emitted as well as restriction of NO3-N leaching.
基金funded by the Department for Environment Food & Rural Affairsthe Scottish Government+2 种基金the Department of Agriculture and Rural Development for Northern Irelandthe Welsh Government as part of the UK’s Agricultural GHG Research Platform initiative
文摘Although the effect of animal and diet factors on enteric methane （CH4） emissions from confined cattle has been extensively examined, less data is available regarding CH4 emissions from grazing young cattle. A study was undertaken to evaluate the effect of the physiological state of Holstein-Friesian heifers on their enteric CH4 emissions while grazing a perennial ryegrass sward. Two experiments were conducted： Experiment 1 ran from May 2011 for 11 weeks and Experiment 2 ran from August 2011 for 10 weeks. In each experiment, Holstein-Friesian heifers were divided into three treatment groups （12 animals/group） consisting of calves, yearling heifers, and in-calf heifers （average ages： 8.5, 14.5, and 20.5 months, respectively）. Methane emissions were estimated for each animal in the final week of each experiment using the sulfur hexafluoride tracer technique. Dry matter （DM） intake was estimated using the calculated metabolizable energy （ME） requirement divided by the ME concentration in the grazed grass. As expected, live weight increased with increasing animal age （P 〈 0.001）; however, there was no difference in live weight gain among the three groups in Experiment 1, although in Experiment 2, this variable decreased with increasing animal age （P 〈 0.001 ）. In Experiment 1, yearling heifers had the highest CH4 emissions （g·d^-1） and in-calf heifers produced more than calves （P 〈 0.001 ）. When expressed as CH4 emissions per unit of live weight, DM intake, and gross energy （GE） intake, yearling heifers had higher emission rates than calves and in-calf heifers （P 〈 0.001）. However, the effects on CH4 emissions were different in Experiment 2, in which CH, emissions （g·d^-1） increased linearly with increasing animal age （P 〈 0.001）, although the difference between yearling and in-calf heifers was not significant. The CH4/live weight ratio was lower in in-calf heifers than in the other two groups （P 〈 0.001 ）, while CH4 energy output as a proportion of GE intake was lower in calves than in yearling and in-calf heifers （P 〈 0.05）. All data were then pooled and used to develop prediction equations for CH4 emissions. All relationships are significant （P 〈 0.001）, with R2 values ranging from 0.630 to 0.682. These models indicate that CH4 emissions could be increased by 0.252 g.d-1 with an increase of I kg live weight or by 14.9 g·d^-1 with an increase of 1 kg·d^-1 of DM intake; or, the CH4 energy output could be increased by 0.046 MJ·d^-1 with an increase of 1 MJ·d^-1 of GE intake. These results provide an alternative approach for estimating CH4 emissions from grazine dairy heifers when actual CH, emission data are not available.
基金the One-hundred Talents Program of CAS,the Special Fund for Agricultural Profession (200803030)the Sino-German project (DFG Training Group,GK1070)
文摘Atmospheric nitrogen (N) deposition has been poorly documented in northern China, an intensive agricultural and industrial region with large emissions of NHx and NOy. To quantify N deposition, total airborne N deposition was determined at three agricultural sites using a manual integrated total nitrogen input (ITNI) system during growth of winter wheat (Triticum aestivum L.) and Italian ryegrass (Lolium multiflorum Lam.) from September 2005 to May 2006. Total estimated N deposition averaged 54.9 and 43.2 kg N/hm2 across the three sites when wheat was grown to flowering and maturing, respectively. The average value was 50.2 kg N/hm2 when ryegrass was the indicator plant. Both indicator species gave similar total airborne N input results. The intermediate level of N supplied resulted in the highest N deposition, and the ratio of N acquired from deposition to total N content of the whole system decreased with increasing N supply to the roots. The contribution of atmospheric N to the total N content of the wheat and ryegrass sand culture systems ranged from 10% to 24%.
基金the International Cooperation Project of Chinese Ministry of Sciences and Technology (2014DFA32860) for the financial support
文摘Pig and poultry production in China had experienced considerable changes from 1960 to 2010. The present study aimed to evaluate the effects of these changes on greenhouse gas emission inventeries （expressed as CO2 equivalent） from these two sectors. The inventories included methane emissions from enteric fermentation, methane and nitrous oxide production from manure management. The greenhouse gas emissions from these sources in 2010 in pig sector were 17, 62 and 21%, respectively, and that in poultry sector （including chicken, duck, goose and others） were 1, 18 and 81%, respectively. Total CO2 equivalent increased from 1960 to 2010 in both pig （11 582 to 55564 Gg yr-1） and poultry （1 497 to 14 873 Gg yr-1） sectors. Within poultry sector, emissions from chicken, duck, goose and others accounted for 74, 15, 11 and 0.01% in 2010, respectively. However, during the last 50 years, these emissions continuously reduced when related to production of I kg of pork （8.01 to 1.14 kg kg-1）, poultry meat （1.19 to 0.37 kg kg-1） and egg （0.47 to 0.33 kg kg-1）, which is mainly associated with the continuous improvement in production efficiency in all management systems. These results provide benchmark information for Chinese authorities to develop appropriate policies and mitigation strategies to reduce greenhouse gas emissions from pig and poultry sectors.
基金the Key Program for International S&T Cooperation Projects of China(2022YFE0130100)Central Public-interest Scientific Institution Basal Research Fund of Chinese Academy of Agricultural Sciences(Y2022GH12).
文摘Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows.
文摘Localized cell wall thickenings, so called papillae, are a common plant defense response to fungal attack at sites of penetration of the plant cell. The major constituent of papillae is callose, a (1,3)-β-glucan polymer, which contributes to slowing or blocking the invading fungal hyphae. In the model plant Arabidopsis thaliana, we could recently show that the overexpression of PMR4(POWDERY MILDEW RESITANT 4), which encodes a stress induced callose synthase, results in complete powdery mildew resistance. To evaluate if these findings are also transferable to monocot crops, we transiently expressed PMR4 under control of the 35S promoter in leaves of barley (Hordeum vulgare) seedlings, which were subsequently inoculated with the virulent powdery mildew Blumeria graminis f. sp. hordei. Fusion of the green fluorescent protein (GFP) to PMR4 allowed the identification of successfully transformed barley cells, which showed an increased penetration resistance to B. graminis compared to control cells that express only GFP.PMR4-GFP localized in a similar pattern at the site of attempted fungal penetration as observed inA. thaliana, which suggests that similar transport mechanisms of the callose synthase might exist in dicot and monocot plants.
基金Supported by the National Natural Science Foundation of China(Nos.30870456 and 30911130503)
文摘We investigated 15N abundance （δ15N） of winter wheat （Triticum aestivum cv. Jinmai 1） plants and soil at different growth stages in a field with a 13-year fertilization history of urea and compost, to determine whether or not the δ15N of plant parts can be used as an indicator of organic amendment with compost. Plant parts （roots, leaves, stems and grains） and soil were sampled at re-greening, jointing, grain filling and mature growth stages of winter wheat. There were significant differences between the urea and compost treatments in 815N of whole plants, plant parts and soil over the whole growing season. Determination of the δ15N of plant parts was more convenient than that of whole plant to distinguish between the application of organic amendment and synthetic N fertilizer.
基金the National Natural Science Foundation of China(Nos.41530857 and 41471208)the National Key Basic Research Program of China(No.2015CB150501)+2 种基金the Department of Agriculture,Environment,and Rural Affairs(DAERA)in Northern Ireland,UK(No.700141499)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB15040000)the Startup Foundation for Introducing Talent of the Nanjing University of Information Science and Technology(NUIST),China(No.S8113117001).
文摘Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly understood.Using a 44-year grassland fertilization experiment,we investigated community shifts of active nitrifiers by DNA-based stable isotope probing(SIP)of field soils that received no fertilization(CK),high levels of organic cattle manure(HC),and chemical N fertilization(CF).Incubation of DNA-SIP microcosms showed significant nitrification activities in CF and HC soils,whereas no activity occurred in CK soils.The 44 years of inorganic N fertilization selected only 13C-ammonia-oxidizing bacteria(AOB),whereas cattle slurry applications created a niche in which both ammonia-oxidizing archaea(AOA)and AOB could be actively13C-labeled.Phylogenetic analysis indicated that Nitrosospira sp.62-like AOB dominated inorganically fertilized CF soils,while Nitrosospira sp.41-like AOB were abundant in organically fertilized HC soils.The 13C-AOA in HC soils were affiliated with the 29i4 lineage.The 13C-nitrite-oxidizing bacteria(NOB)were dominated by both Nitrospira-and Nitrobacter-like communities in CF soils,and the latter was overwhelmingly abundant in HC soils.The 13C-labeled nitrifying communities in SIP microcosms of CF and HC soils were largely similar to those predominant under field conditions.These results provide direct evidence for a strong selection of distinctly active nitrifiers after 44 years of different fertilization regimes in the field.Our findings imply that niche differentiation of nitrifying communities could be assessed as a net result of microbial adaption over 44 years to inorganic and organic N fertilization in the field,where distinct nitrifiers have been shaped by intensified anthropogenic N input.
