The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid o...The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid our atmosphere of the main anthropogenic gas while allowing for the continuous use of the fossil fuels which still power today’s world.Underground storage of CO2 involves the injection of CO2 into suitable geological formations and the monitoring of the injected plume over time,to ensure containment.Over the last two or three decades,attention has been paid to technology developments of carbon capture and sequestration.Therefore,it is high time to look at the research done so far.In this regard,a high-level review article is required to provide an overview of the status of carbon capture and sequestration research.This article presents a review of CO2 storage technologies which includes a background of essential concepts in storage,the physical processes involved,modeling procedures and simulators used,capacity estimation,measuring monitoring and verification techniques,risks and challenges involved and field-/pilot-scale projects.It is expected that the present review paper will help the researchers to gain a quick knowledge of CO2 sequestration for future research in this field.展开更多
Background:Lentinan(LNT)may regulate many important physiological functions of human and animals.This study aimed to verify whether LNT administration could relieve diarrhea via improving gut immunity in rotavirus(RV)...Background:Lentinan(LNT)may regulate many important physiological functions of human and animals.This study aimed to verify whether LNT administration could relieve diarrhea via improving gut immunity in rotavirus(RV)-challenged weaned pigs.Methods:Twenty-eight weaned pigs were randomly fed 2 diets containing 0 or 84 mg/kg LNT product for 19 d(n=14).RV infection was executed on d 15.After extracting polysaccharides from LNT product,its major monosaccharides were analyzed.Then,LNT polysaccharide was used to administrate RV-infected IPEC-J2 cells.Results:Dietary LNT supplementation supported normal function of piglets even when infected with RV,as reflected by reduced growth performance loss and diarrhea prevalence,and maintained gut immunity(P<0.05).The polysaccharide was isolated from LNT product,which molecular weight was 5303 Da,and major monosaccharides included glucose,arabinose and galactose.In RV-infected IPEC-J2 cells,this polysaccharide significantly increased cell viability(P<0.05),and significantly increased anti-virus immunity via regulating pattern recognition receptors and host defense peptides(P<0.05).Conclusion:Those results suggest that LNT administration increases the piglets’resistance to RV-induced stress,likely by supporting intestinal immunity.展开更多
Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices.The use of RGB images taken from UAVs may replace the traditional vi...Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices.The use of RGB images taken from UAVs may replace the traditional visual counting in fields with improved throughput,accuracy,and access to plant localization.However,high-resolution images are required to detect the small plants present at the early stages.This study explores the impact of image ground sampling distance(GSD)on the performances of maize plant detection at three-to-five leaves stage using Faster-RCNN object detection algorithm.Data collected at high resolution(GSD≈0:3 cm)over six contrasted sites were used for model training.Two additional sites with images acquired both at high and low(GSD≈0:6 cm)resolutions were used to evaluate the model performances.Results show that Faster-RCNN achieved very good plant detection and counting(rRMSE=0:08)performances when native high-resolution images are used both for training and validation.Similarly,good performances were observed(rRMSE=0:11)when the model is trained over synthetic low-resolution images obtained by downsampling the native training high-resolution images and applied to the synthetic low-resolution validation images.Conversely,poor performances are obtained when the model is trained on a given spatial resolution and applied to another spatial resolution.Training on a mix of high-and low-resolution images allows to get very good performances on the native high-resolution(rRMSE=0:06)and synthetic low-resolution(rRMSE=0:10)images.However,very low performances are still observed over the native low-resolution images(rRMSE=0:48),mainly due to the poor quality of the native low-resolution images.Finally,an advanced super resolution method based on GAN(generative adversarial network)that introduces additional textural information derived from the native high-resolution images was applied to the native low-resolution validation images.Results show some significant improvement(rRMSE=0:22)compared to bi展开更多
The Global Wheat Head Detection(GWHD)dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4700 RGB images acquired from various acquisition platforms and 7 countries/institutions.With an ass...The Global Wheat Head Detection(GWHD)dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4700 RGB images acquired from various acquisition platforms and 7 countries/institutions.With an associated competition hosted in Kaggle,GWHD_2020 has successfully attracted attention from both the computer vision and agricultural science communities.From this first experience,a few avenues for improvements have been identified regarding data size,head diversity,and label reliability.To address these issues,the 2020 dataset has been reexamined,relabeled,and complemented by adding 1722 images from 5 additional countries,allowing for 81,553 additional wheat heads.We now release in 2021 a new version of the Global Wheat Head Detection dataset,which is bigger,more diverse,and less noisy than the GWHD_2020 version.展开更多
The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mit...The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.展开更多
Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides.Hemicelluloses are main components of cell walls of cereal grains.Moreover,hemicelluloses are considered as potential sources of mono-and oli...Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides.Hemicelluloses are main components of cell walls of cereal grains.Moreover,hemicelluloses are considered as potential sources of mono-and oligosaccharides.In this study,influence of xylanase on the physicochemical properties and sensory qualities of the whole wheat bread during storage was investigated.Studies of whole wheat bread on microstructure,texture,thermotics,Scanning Electron Microscopic(SEM),X-Ray Diffraction(XRD)were conducted at ambient temperature of 25 and 4◦C respectively.During storage at different temperatures,bread containing xylanase exhibited less firmness but larger volume with whiter crumb color and longer shelf life as compared to control bread.Results of firmness,enthalpy,Fourier Transformation Infra Red(FTIR)and X-Ray Diffraction(XRD)studies suggested a lower staling rate of bread containing xylanase as compared to control one.Bread containing xylanase showed a smoother surface and more uniform pore size than the control.Significant differences in microstructure of control and bread containing xylanase were observed which might be attributed due to the change in water starch gluten interaction.These differences were also found to be interrelated to the textural properties of bread.Better sensory features were achieved in bread containing xylanase.展开更多
Undoped nickel-based catalysts supported on depleted uranium oxide allow one to carry out CO_(2)methanation process under extremely low reaction temperature under atmospheric pressure and powered by a contactless indu...Undoped nickel-based catalysts supported on depleted uranium oxide allow one to carry out CO_(2)methanation process under extremely low reaction temperature under atmospheric pressure and powered by a contactless induction heating.By adjusting the reaction conditions,the catalyst is able to perform CO_(2)methanation reaction under autothermal process operated inside a non-adiabatic reactor,without any external energy supply.Such autothermal process is possible thanks to the high apparent density of the UO_x which allows one to confine the reaction heat in a small catalyst volume in order to confine the exothermicity of the reaction inside the catalyst and to operate the reaction at equilibrium heat in-heat out.Such autothermal operation mode allows one to significantly reduce the complexity of the process compared to that operated using adiabatic reactor,where complete insulation is required to prevent heat disequilibrium,in order to reduce as much as possible,the heat exchange with the external medium.The catalyst displays an extremely high stability as a function of time on stream as no apparent deactivation.It is expected that such new catalyst with unprecedented catalytic performance could open new era in the field of heterogeneous catalysis where traditional supports show their limitations to operate catalytic processes under severe reaction conditions.展开更多
Cottonseed protein concentrate is a sustainable fishmeal alternative in aquafeed.A 10-week experiment was conducted to investigate the effects of a cottonseed protein concentrate-based diet with and without multi-stra...Cottonseed protein concentrate is a sustainable fishmeal alternative in aquafeed.A 10-week experiment was conducted to investigate the effects of a cottonseed protein concentrate-based diet with and without multi-strain yeast fractions(MsYF)on growth,bile acid metabolism,and health in largemouth bass.Four hundred fish(54.0±0.0 g)were casually distributed into 16 tanks(4 replicates/diet).Fish were fed with 4 iso-nitrogen and iso-energetic diets 3 times daily,including a fishmeal diet(FM),a soy protein concentrate-based diet(SPC;replacing 81%fishmeal protein),a cottonseed protein concentrate-based diet(CPC;replacing 81%fishmeal protein),and a CPC diet supplemented with 800 mg/kg MsYF(CPCY).Results showed that the survival of SPC was the lowest,i.e.,48%,with no apparent diet effect among other treatments;we omitted the SPC in additional analyses.Fish fed cottonseed protein concentrate-based diets showed lower growth than FM(P<0.05).Fish fed CPC showed the highest nuclear dense hepatic phenotypes ratio(50%),followed by CPCY(33%)and FM(17%).Further,dietary CPC increased hepatic total cholesterol and triglyceride levels with concurrently increased cholesterol syn-thesis but decreased triglyceride synthesis-associated transcription levels(P<0.05).Furthermore,di-etary CPC increased bile acid synthesis but decreased bile acid transport-associated transcription levels(P<0.05),and then induced an increment of plasma cholic acid and hepatic chenodeoxycholic acid content and the decrement of genus Romboustia(P<0.05).Regarding the effect of MsYF,fish fed CPCY reduced hepatic lipid accumulation and total plasma bile acid content(P<0.05)compared to CPC,suggesting an improvement in liver health.Also,dietary MsYF could reverse the microbiota community structure showing a similar gut microbial composition to FM.In conclusion,81%of fishmeal protein replaced by cottonseed protein concentrate suppressed growth and liver health,while dietary MsYF might mitigate the negative impact of a high cottonseed protein concentrate level diet on展开更多
This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of know...This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.展开更多
We report on the magnetic,magnetocaloric,thermal,and electrical transport properties of Tb_(4)Coln alloy,which crystallizes in two phases,Tb_6Co_(2.1)In_(0.8)(space group Immm)and Tb_(2)In_(0.9)Co_(0.1)(space group P6...We report on the magnetic,magnetocaloric,thermal,and electrical transport properties of Tb_(4)Coln alloy,which crystallizes in two phases,Tb_6Co_(2.1)In_(0.8)(space group Immm)and Tb_(2)In_(0.9)Co_(0.1)(space group P6_(3)/mmc),respectively.The alloy reveals three successive magnetic transitions around T_(1)(163 K),T_(2)(50 K),and T_(3)(29 K),respectively,associated with paramagnetic to ferromagnetic transition and two sequential antiferromagnetic transitions.The low-temperature transition T_(3) follows the first-order magnetic behavior and exhibits the field-induced magnetic transition.Meanwhile,T_(2) and T_(1) are found to be second-order in nature which opens a possibility for hysteresis-free magnetocaloric application.The magnetocaloric properties are determined using different magnetocaloric figures of merits such as-ΔS_(M),ΔT_(ad).RCP,and TEC(10).Additionally,the universal curve behavior in the isothermal entropy change unveils the variation in critical exponents around T_(1) and T_(2) due to the magnetic inhomogeneity in the alloy.Besides,the electrical transport properties of the metallic alloy denote the maximum magnetoresistance of-10%around T_(1).展开更多
Magnesium alloys are important materials for application in the automotive and aviation industries. During the last few years, the number of possible applications as biodegradable implants in medicine has grown. Mg-RE...Magnesium alloys are important materials for application in the automotive and aviation industries. During the last few years, the number of possible applications as biodegradable implants in medicine has grown. Mg-RE（rare earth） alloys belong to the most advanced group of products, offering the best combination of mechanical properties and corrosion resistance. Among these materials, WE43（Mg-Y-Nd）is a very well-known commercial alloy that has been extensively studied for applications at increased temperatures and also in organisms. Although this material has been described, there are still possibilities to improve its properties and subsequently expand its applicability. Powder metallurgy has already been used for the preparation of magnesium alloys with superior mechanical properties and occasionally superior corrosion properties. Therefore, the present paper is oriented toward the preparation of Mg-4Y-3RE-Zr（WE43） alloy by the powder metallurgy technique（WE43-PM） and comparison of the final properties with the product of extrusion of as-cast ingot（WE43-IM）. Our processing leads to a partial improvement in the mechanical properties and superior corrosion resistance of WE43-PM. The texture strength of WE43-PM was low, and therefore, anisotropy of mechanical properties was suppressed.展开更多
Pixel segmentation of high-resolution RGB images into chlorophyll-active or nonactive vegetation classes is a first step often required before estimating key traits of interest.We have developed the SegVeg approach fo...Pixel segmentation of high-resolution RGB images into chlorophyll-active or nonactive vegetation classes is a first step often required before estimating key traits of interest.We have developed the SegVeg approach for semantic segmentation of RGB images into three classes(background,green,and senescent vegetation).This is achieved in two steps:A U-net model is first trained on a very large dataset to separate whole vegetation from background.The green and senescent vegetation pixels are then separated using SVM,a shallow machine learning technique,trained over a selection of pixels extracted from images.The performances of the SegVeg approach is then compared to a 3-class U-net model trained using weak supervision over RGB images segmented with SegVeg as groundtruth masks.Results show that the SegVeg approach allows to segment accurately the three classes.However,some confusion is observed mainly between the background and senescent vegetation,particularly over the dark and bright regions of the images.The U-net model achieves similar performances,with slight degradation over the green vegetation:the SVM pixel-based approach provides more precise delineation of the green and senescent patches as compared to the convolutional nature of U-net.The use of the components of several color spaces allows to better classify the vegetation pixels into green and senescent.Finally,the models are used to predict the fraction of three classes over whole images or regularly spaced grid-pixels.Results show that green fraction is very well estimated(R^(2)=0.94)by the SegVeg model,while the senescent and background fractions show slightly degraded performances(R^(2)=0.70 and 0.73,respectively)with a mean 95%confidence error interval of 2.7%and 2.1%for the senescent vegetation and background,versus 1%for green vegetation.We have made SegVeg publicly available as a ready-to-use script and model,along with the entire annotated grid-pixels dataset.We thus hope to render segmentation accessible to a broad audience by requiring neither展开更多
The deterioration of recycled fibers especially unbleached kraft with high wet strength resin content due to the irreversible structural changes caused by drying and added chemicals makes the raw material difficult to...The deterioration of recycled fibers especially unbleached kraft with high wet strength resin content due to the irreversible structural changes caused by drying and added chemicals makes the raw material difficult to repulp.The mechanical effect in the pulper over time with chemical treatment has a negative impact on the recycled fibers.At lab scale,different compositions of enzymatic treatment C022L were under investigation to select the most efficient laccase Lacc1,Lacc2 or Lacc3 and to observe the impact of lipases during repulping at low and high consistencies.Pulp disintegration at different times was evaluated to define the level of rejects and to analyze the morphology of fibers after treatments.These results were more significant for Lacc2,by increasing the pulp consistency to 15%in the pulper.Combining lipases with CELODASE 022L appeared to decrease the efficiency of enzymes.The results showed a high reduction of energy power with the enzymatic treatment and a significant reduction of fines level in fibers’suspension.The most efficient version of C022L was used at industrial scale to compare directly with the standard conditions used in a paper mill.展开更多
This study presents the multifunctional characteristics of multi-walled carbon nanotube(MWCNT)/polypropylene random copolymer(PPR) composites enabled via fused filament fabrication(FFF) under monotonic and quasi-stati...This study presents the multifunctional characteristics of multi-walled carbon nanotube(MWCNT)/polypropylene random copolymer(PPR) composites enabled via fused filament fabrication(FFF) under monotonic and quasi-static cyclic compression. Utilizing in-house MWCNT-engineered PPR filament feedstocks, both bulk and cellular composites were realized. The morphological features of nanocomposites were examined via scanning electron microscopy, which reveals that MWCNTs are uniformly dispersed. The uniformly dispersed MWCNTs forms an electrically conductive network within the PPR matrix, and the resulting nanocomposite shows good electrical conductivity(~10^(-1)S/cm), improved mechanical performance(modulus increases by 125% and compressive strength increases by 25% for 8 wt% MWCNT loading) and pronounced piezoresistive response(gauge factor of 27.9-8.5 for bulk samples)under compression. The influence of strain rate on the piezoresistive response of bulk samples(4 wt% of MWCNT) under compression was also measured. Under repeated cyclic compression(2% constant strain amplitude), the nanocomposite exhibited stable piezoresistive performance up to 100 cycles. The piezoresistive response under repeated cyclic loading with increasing strain amplitude of was also assessed.The gauge factor of BCC and FCC cellular composites(4 wt% of MWCNT) with a relative density of 30%was observed to be 46.4 and 30.2 respectively, under compression. The higher sensitivity of the BCC plate-lattice could be attributed to its higher degree of stretching-dominated deformation behavior than the FCC plate-lattice, which exhibits bending-dominated behavior. The 3D printed cellular PPR/MWCNT composites structures were found to show excellent piezoresistive self-sensing characteristics and open new avenues for in situ structural health monitoring in various applications.展开更多
The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine...The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine(Met)sources DL-methionine(DL-Met)and DL-2-hydroxy-4-(methylthio)butanoic acid(HMTBa).The difference in the chemical structures of HMTBa and DL-Met indicates that these molecules are absorbed and metabolized differently in animals.This review explores the methodologies used to describe the 2-step enzymatic conversion of the 3 enantiomers(D-HMTBa,L-HMTBa and D-Met)to L-Met,as well as the site of conversion at the organ and tissue levels.Extensive work was published documenting the conversion of HMTBa and D-Met into L-Met and,consequently,the incorporation into protein using a variety of in vitro techniques,such as tissue homogenates,cell lines,primary cell lines,and everted gut sacs of individual tissues.These studies illustrated the role of the liver,kidney,and intestine in the con-version of Met precursors into L-Met.A combination of in vivo studies using stable isotopes and infusions provided evidence of the wide conversion of HMTBa to L-Met by all tissues and how some tissues are net users of HMTBa,whereas others are net secreters of L-Met derived from HMTBa.Conversion of D-Met to L-Met in organs other than the liver and kidney is poorly documented.The methodology cited in the literature to determine conversion efficiency ranged from measurements of urinary,fecal,and respiratory excretion to plasma concentration and tissue incorporation of isotopes after intraperitoneal and oral in-fusions.Differences observed between these methodologies reflect differences in the metabolism of Met sources rather than differences in conversion efficiency.The factors affecting conversion efficiency are explored in this paper and are mostly associated with extreme dietary conditions,such as noncommercial crystalline diets that are very deficient in total sulfur amino acids with respect to requirements.Impli-cations 展开更多
基金support provided by the Department of Petroleum Engineering,Khalifa University of Science and Technology,Sas Al Nakhl Campus,Abu Dhabi,UAE
文摘The merits of CO2 capture and storage to the environmental stability of our world should not be underestimated as emissions of greenhouse gases cause serious problems.It represents the only technology that might rid our atmosphere of the main anthropogenic gas while allowing for the continuous use of the fossil fuels which still power today’s world.Underground storage of CO2 involves the injection of CO2 into suitable geological formations and the monitoring of the injected plume over time,to ensure containment.Over the last two or three decades,attention has been paid to technology developments of carbon capture and sequestration.Therefore,it is high time to look at the research done so far.In this regard,a high-level review article is required to provide an overview of the status of carbon capture and sequestration research.This article presents a review of CO2 storage technologies which includes a background of essential concepts in storage,the physical processes involved,modeling procedures and simulators used,capacity estimation,measuring monitoring and verification techniques,risks and challenges involved and field-/pilot-scale projects.It is expected that the present review paper will help the researchers to gain a quick knowledge of CO2 sequestration for future research in this field.
基金This study was financially supported by the grant from the earmarked fund for the China Agriculture Research System(CARS-35)the fund from the Project of SAU-Adisseo Centre of Research on Nutrition and Healththe fund from Agricultural Science and Technology Achievement Transformation Fund Project of Sichuan Province(2016NYZ0052 and 20NZZH0057).
文摘Background:Lentinan(LNT)may regulate many important physiological functions of human and animals.This study aimed to verify whether LNT administration could relieve diarrhea via improving gut immunity in rotavirus(RV)-challenged weaned pigs.Methods:Twenty-eight weaned pigs were randomly fed 2 diets containing 0 or 84 mg/kg LNT product for 19 d(n=14).RV infection was executed on d 15.After extracting polysaccharides from LNT product,its major monosaccharides were analyzed.Then,LNT polysaccharide was used to administrate RV-infected IPEC-J2 cells.Results:Dietary LNT supplementation supported normal function of piglets even when infected with RV,as reflected by reduced growth performance loss and diarrhea prevalence,and maintained gut immunity(P<0.05).The polysaccharide was isolated from LNT product,which molecular weight was 5303 Da,and major monosaccharides included glucose,arabinose and galactose.In RV-infected IPEC-J2 cells,this polysaccharide significantly increased cell viability(P<0.05),and significantly increased anti-virus immunity via regulating pattern recognition receptors and host defense peptides(P<0.05).Conclusion:Those results suggest that LNT administration increases the piglets’resistance to RV-induced stress,likely by supporting intestinal immunity.
文摘Early-stage plant density is an essential trait that determines the fate of a genotype under given environmental conditions and management practices.The use of RGB images taken from UAVs may replace the traditional visual counting in fields with improved throughput,accuracy,and access to plant localization.However,high-resolution images are required to detect the small plants present at the early stages.This study explores the impact of image ground sampling distance(GSD)on the performances of maize plant detection at three-to-five leaves stage using Faster-RCNN object detection algorithm.Data collected at high resolution(GSD≈0:3 cm)over six contrasted sites were used for model training.Two additional sites with images acquired both at high and low(GSD≈0:6 cm)resolutions were used to evaluate the model performances.Results show that Faster-RCNN achieved very good plant detection and counting(rRMSE=0:08)performances when native high-resolution images are used both for training and validation.Similarly,good performances were observed(rRMSE=0:11)when the model is trained over synthetic low-resolution images obtained by downsampling the native training high-resolution images and applied to the synthetic low-resolution validation images.Conversely,poor performances are obtained when the model is trained on a given spatial resolution and applied to another spatial resolution.Training on a mix of high-and low-resolution images allows to get very good performances on the native high-resolution(rRMSE=0:06)and synthetic low-resolution(rRMSE=0:10)images.However,very low performances are still observed over the native low-resolution images(rRMSE=0:48),mainly due to the poor quality of the native low-resolution images.Finally,an advanced super resolution method based on GAN(generative adversarial network)that introduces additional textural information derived from the native high-resolution images was applied to the native low-resolution validation images.Results show some significant improvement(rRMSE=0:22)compared to bi
基金the French National Research Agency under the Investments for the Future Program,referred as ANR-16-CONV-0004 PIA#Digitag.Institut Convergences Agriculture Numérique,Hiphen supported the organization of the competition.Japan:Kubota supported the organization of the competi-tion.Australia:Grains Research and Development Corpora-tion(UOQ2002-008RTX machine learning applied to high-throughput feature extraction from imagery to map spatial variability and UOQ2003-011RTX INVITA-a technology and analytics platform for improving variety selection)sup-ported competition.
文摘The Global Wheat Head Detection(GWHD)dataset was created in 2020 and has assembled 193,634 labelled wheat heads from 4700 RGB images acquired from various acquisition platforms and 7 countries/institutions.With an associated competition hosted in Kaggle,GWHD_2020 has successfully attracted attention from both the computer vision and agricultural science communities.From this first experience,a few avenues for improvements have been identified regarding data size,head diversity,and label reliability.To address these issues,the 2020 dataset has been reexamined,relabeled,and complemented by adding 1722 images from 5 additional countries,allowing for 81,553 additional wheat heads.We now release in 2021 a new version of the Global Wheat Head Detection dataset,which is bigger,more diverse,and less noisy than the GWHD_2020 version.
基金support by University of Orleans,la Region Centre(HabitAsthmeN8201200073535)and Conseil General45 to F.M.as PhD fellowship.
文摘The cysteine protease caspase-1(Casp-1)contributes to innate immunity through the assembly of NLRP3,NLRC4,AIM2,and NLRP6 inflammasomes.Here we ask whether caspase-1 activation plays a regulatory role in house dust mite(HDM)-induced experimental allergic airway inflammation.We report enhanced airway inflammation in caspase-1-deficient mice exposed toHDMwith a marked eosinophil recruitment,increased expression of IL-4,IL-5,IL-13,aswell as full-length and bioactive IL-33.Furthermore,mice deficient for NLRP3 failed to control eosinophil influx in the airways and displayed augmented Th2 cytokine and chemokine levels,suggesting that the NLPR3 inflammasome complex controls HDM-induced inflammation.IL-33 neutralization by administration of soluble ST2 receptor inhibited the enhanced allergic inflammation,while administration of recombinant IL-33 during challenge phase enhanced allergic inflammation in caspase-1-deficient mice.Therefore,we show that caspase-1,NLRP3,and ASC,but not NLRC4,contribute to the upregulation of allergic lung inflammation.Moreover,we cannot exclude an effect of caspase-11,because caspase-1-deficient mice are deficient for both caspases.Mechanistically,absence of caspase-1 is associated with increased expression of IL-33,uric acid,and spleen tyrosine kinase(Syk)production.This study highlights acritical role of caspase-1 activation andNLPR3/ASCinflammasomecomplex in the down-modulation of IL-33 in vivo and in vitro,thereby regulating Th2 response in HDM-induced allergic lung inflammation.
文摘Xylanase is a hemicellulase that can hydrolyses the complex polysaccharides.Hemicelluloses are main components of cell walls of cereal grains.Moreover,hemicelluloses are considered as potential sources of mono-and oligosaccharides.In this study,influence of xylanase on the physicochemical properties and sensory qualities of the whole wheat bread during storage was investigated.Studies of whole wheat bread on microstructure,texture,thermotics,Scanning Electron Microscopic(SEM),X-Ray Diffraction(XRD)were conducted at ambient temperature of 25 and 4◦C respectively.During storage at different temperatures,bread containing xylanase exhibited less firmness but larger volume with whiter crumb color and longer shelf life as compared to control bread.Results of firmness,enthalpy,Fourier Transformation Infra Red(FTIR)and X-Ray Diffraction(XRD)studies suggested a lower staling rate of bread containing xylanase as compared to control one.Bread containing xylanase showed a smoother surface and more uniform pore size than the control.Significant differences in microstructure of control and bread containing xylanase were observed which might be attributed due to the change in water starch gluten interaction.These differences were also found to be interrelated to the textural properties of bread.Better sensory features were achieved in bread containing xylanase.
基金ORANO Chimie-Enrichissement Co.for the financial support of this project。
文摘Undoped nickel-based catalysts supported on depleted uranium oxide allow one to carry out CO_(2)methanation process under extremely low reaction temperature under atmospheric pressure and powered by a contactless induction heating.By adjusting the reaction conditions,the catalyst is able to perform CO_(2)methanation reaction under autothermal process operated inside a non-adiabatic reactor,without any external energy supply.Such autothermal process is possible thanks to the high apparent density of the UO_x which allows one to confine the reaction heat in a small catalyst volume in order to confine the exothermicity of the reaction inside the catalyst and to operate the reaction at equilibrium heat in-heat out.Such autothermal operation mode allows one to significantly reduce the complexity of the process compared to that operated using adiabatic reactor,where complete insulation is required to prevent heat disequilibrium,in order to reduce as much as possible,the heat exchange with the external medium.The catalyst displays an extremely high stability as a function of time on stream as no apparent deactivation.It is expected that such new catalyst with unprecedented catalytic performance could open new era in the field of heterogeneous catalysis where traditional supports show their limitations to operate catalytic processes under severe reaction conditions.
基金supported by the National Key R&D Program of China(2022YFD1300600)Beijing Innovation Consortium of Agriculture Research System(BAIC07-2022).
文摘Cottonseed protein concentrate is a sustainable fishmeal alternative in aquafeed.A 10-week experiment was conducted to investigate the effects of a cottonseed protein concentrate-based diet with and without multi-strain yeast fractions(MsYF)on growth,bile acid metabolism,and health in largemouth bass.Four hundred fish(54.0±0.0 g)were casually distributed into 16 tanks(4 replicates/diet).Fish were fed with 4 iso-nitrogen and iso-energetic diets 3 times daily,including a fishmeal diet(FM),a soy protein concentrate-based diet(SPC;replacing 81%fishmeal protein),a cottonseed protein concentrate-based diet(CPC;replacing 81%fishmeal protein),and a CPC diet supplemented with 800 mg/kg MsYF(CPCY).Results showed that the survival of SPC was the lowest,i.e.,48%,with no apparent diet effect among other treatments;we omitted the SPC in additional analyses.Fish fed cottonseed protein concentrate-based diets showed lower growth than FM(P<0.05).Fish fed CPC showed the highest nuclear dense hepatic phenotypes ratio(50%),followed by CPCY(33%)and FM(17%).Further,dietary CPC increased hepatic total cholesterol and triglyceride levels with concurrently increased cholesterol syn-thesis but decreased triglyceride synthesis-associated transcription levels(P<0.05).Furthermore,di-etary CPC increased bile acid synthesis but decreased bile acid transport-associated transcription levels(P<0.05),and then induced an increment of plasma cholic acid and hepatic chenodeoxycholic acid content and the decrement of genus Romboustia(P<0.05).Regarding the effect of MsYF,fish fed CPCY reduced hepatic lipid accumulation and total plasma bile acid content(P<0.05)compared to CPC,suggesting an improvement in liver health.Also,dietary MsYF could reverse the microbiota community structure showing a similar gut microbial composition to FM.In conclusion,81%of fishmeal protein replaced by cottonseed protein concentrate suppressed growth and liver health,while dietary MsYF might mitigate the negative impact of a high cottonseed protein concentrate level diet on
文摘This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.
基金Project supported by the University Science Park TECHNICOM for Innovation Applications supported by Knowledge Technology (313011D232)supported by the Research&Development Operational Programme funded by the ERDFVEGA1/0705/20,1/0404/21。
文摘We report on the magnetic,magnetocaloric,thermal,and electrical transport properties of Tb_(4)Coln alloy,which crystallizes in two phases,Tb_6Co_(2.1)In_(0.8)(space group Immm)and Tb_(2)In_(0.9)Co_(0.1)(space group P6_(3)/mmc),respectively.The alloy reveals three successive magnetic transitions around T_(1)(163 K),T_(2)(50 K),and T_(3)(29 K),respectively,associated with paramagnetic to ferromagnetic transition and two sequential antiferromagnetic transitions.The low-temperature transition T_(3) follows the first-order magnetic behavior and exhibits the field-induced magnetic transition.Meanwhile,T_(2) and T_(1) are found to be second-order in nature which opens a possibility for hysteresis-free magnetocaloric application.The magnetocaloric properties are determined using different magnetocaloric figures of merits such as-ΔS_(M),ΔT_(ad).RCP,and TEC(10).Additionally,the universal curve behavior in the isothermal entropy change unveils the variation in critical exponents around T_(1) and T_(2) due to the magnetic inhomogeneity in the alloy.Besides,the electrical transport properties of the metallic alloy denote the maximum magnetoresistance of-10%around T_(1).
基金financial support of this research by project No. GA16-08963S
文摘Magnesium alloys are important materials for application in the automotive and aviation industries. During the last few years, the number of possible applications as biodegradable implants in medicine has grown. Mg-RE（rare earth） alloys belong to the most advanced group of products, offering the best combination of mechanical properties and corrosion resistance. Among these materials, WE43（Mg-Y-Nd）is a very well-known commercial alloy that has been extensively studied for applications at increased temperatures and also in organisms. Although this material has been described, there are still possibilities to improve its properties and subsequently expand its applicability. Powder metallurgy has already been used for the preparation of magnesium alloys with superior mechanical properties and occasionally superior corrosion properties. Therefore, the present paper is oriented toward the preparation of Mg-4Y-3RE-Zr（WE43） alloy by the powder metallurgy technique（WE43-PM） and comparison of the final properties with the product of extrusion of as-cast ingot（WE43-IM）. Our processing leads to a partial improvement in the mechanical properties and superior corrosion resistance of WE43-PM. The texture strength of WE43-PM was low, and therefore, anisotropy of mechanical properties was suppressed.
基金The study was partly supported by several projects including ANR PHENOME(Programme d’investissement d’avenir),Digitag(PIA Institut Convergences Agriculture Numérique ANR-16-CONV-0004),CASDAR LITERAL,and P2S2 funded by CNES.
文摘Pixel segmentation of high-resolution RGB images into chlorophyll-active or nonactive vegetation classes is a first step often required before estimating key traits of interest.We have developed the SegVeg approach for semantic segmentation of RGB images into three classes(background,green,and senescent vegetation).This is achieved in two steps:A U-net model is first trained on a very large dataset to separate whole vegetation from background.The green and senescent vegetation pixels are then separated using SVM,a shallow machine learning technique,trained over a selection of pixels extracted from images.The performances of the SegVeg approach is then compared to a 3-class U-net model trained using weak supervision over RGB images segmented with SegVeg as groundtruth masks.Results show that the SegVeg approach allows to segment accurately the three classes.However,some confusion is observed mainly between the background and senescent vegetation,particularly over the dark and bright regions of the images.The U-net model achieves similar performances,with slight degradation over the green vegetation:the SVM pixel-based approach provides more precise delineation of the green and senescent patches as compared to the convolutional nature of U-net.The use of the components of several color spaces allows to better classify the vegetation pixels into green and senescent.Finally,the models are used to predict the fraction of three classes over whole images or regularly spaced grid-pixels.Results show that green fraction is very well estimated(R^(2)=0.94)by the SegVeg model,while the senescent and background fractions show slightly degraded performances(R^(2)=0.70 and 0.73,respectively)with a mean 95%confidence error interval of 2.7%and 2.1%for the senescent vegetation and background,versus 1%for green vegetation.We have made SegVeg publicly available as a ready-to-use script and model,along with the entire annotated grid-pixels dataset.We thus hope to render segmentation accessible to a broad audience by requiring neither
文摘The deterioration of recycled fibers especially unbleached kraft with high wet strength resin content due to the irreversible structural changes caused by drying and added chemicals makes the raw material difficult to repulp.The mechanical effect in the pulper over time with chemical treatment has a negative impact on the recycled fibers.At lab scale,different compositions of enzymatic treatment C022L were under investigation to select the most efficient laccase Lacc1,Lacc2 or Lacc3 and to observe the impact of lipases during repulping at low and high consistencies.Pulp disintegration at different times was evaluated to define the level of rejects and to analyze the morphology of fibers after treatments.These results were more significant for Lacc2,by increasing the pulp consistency to 15%in the pulper.Combining lipases with CELODASE 022L appeared to decrease the efficiency of enzymes.The results showed a high reduction of energy power with the enzymatic treatment and a significant reduction of fines level in fibers’suspension.The most efficient version of C022L was used at industrial scale to compare directly with the standard conditions used in a paper mill.
基金financial support from the Abu Dhabi National Oil Company (ADNOC), United Arab Emirates under Award No: EX2016-000010。
文摘This study presents the multifunctional characteristics of multi-walled carbon nanotube(MWCNT)/polypropylene random copolymer(PPR) composites enabled via fused filament fabrication(FFF) under monotonic and quasi-static cyclic compression. Utilizing in-house MWCNT-engineered PPR filament feedstocks, both bulk and cellular composites were realized. The morphological features of nanocomposites were examined via scanning electron microscopy, which reveals that MWCNTs are uniformly dispersed. The uniformly dispersed MWCNTs forms an electrically conductive network within the PPR matrix, and the resulting nanocomposite shows good electrical conductivity(~10^(-1)S/cm), improved mechanical performance(modulus increases by 125% and compressive strength increases by 25% for 8 wt% MWCNT loading) and pronounced piezoresistive response(gauge factor of 27.9-8.5 for bulk samples)under compression. The influence of strain rate on the piezoresistive response of bulk samples(4 wt% of MWCNT) under compression was also measured. Under repeated cyclic compression(2% constant strain amplitude), the nanocomposite exhibited stable piezoresistive performance up to 100 cycles. The piezoresistive response under repeated cyclic loading with increasing strain amplitude of was also assessed.The gauge factor of BCC and FCC cellular composites(4 wt% of MWCNT) with a relative density of 30%was observed to be 46.4 and 30.2 respectively, under compression. The higher sensitivity of the BCC plate-lattice could be attributed to its higher degree of stretching-dominated deformation behavior than the FCC plate-lattice, which exhibits bending-dominated behavior. The 3D printed cellular PPR/MWCNT composites structures were found to show excellent piezoresistive self-sensing characteristics and open new avenues for in situ structural health monitoring in various applications.
文摘The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine(Met)sources DL-methionine(DL-Met)and DL-2-hydroxy-4-(methylthio)butanoic acid(HMTBa).The difference in the chemical structures of HMTBa and DL-Met indicates that these molecules are absorbed and metabolized differently in animals.This review explores the methodologies used to describe the 2-step enzymatic conversion of the 3 enantiomers(D-HMTBa,L-HMTBa and D-Met)to L-Met,as well as the site of conversion at the organ and tissue levels.Extensive work was published documenting the conversion of HMTBa and D-Met into L-Met and,consequently,the incorporation into protein using a variety of in vitro techniques,such as tissue homogenates,cell lines,primary cell lines,and everted gut sacs of individual tissues.These studies illustrated the role of the liver,kidney,and intestine in the con-version of Met precursors into L-Met.A combination of in vivo studies using stable isotopes and infusions provided evidence of the wide conversion of HMTBa to L-Met by all tissues and how some tissues are net users of HMTBa,whereas others are net secreters of L-Met derived from HMTBa.Conversion of D-Met to L-Met in organs other than the liver and kidney is poorly documented.The methodology cited in the literature to determine conversion efficiency ranged from measurements of urinary,fecal,and respiratory excretion to plasma concentration and tissue incorporation of isotopes after intraperitoneal and oral in-fusions.Differences observed between these methodologies reflect differences in the metabolism of Met sources rather than differences in conversion efficiency.The factors affecting conversion efficiency are explored in this paper and are mostly associated with extreme dietary conditions,such as noncommercial crystalline diets that are very deficient in total sulfur amino acids with respect to requirements.Impli-cations
