The study of microbial hydrocarbons removal is of great importance for the development of future bioremediation strategies.In this study,we evaluated the removal of a gaseous mixture containing toluene,m-xylene,ethylb...The study of microbial hydrocarbons removal is of great importance for the development of future bioremediation strategies.In this study,we evaluated the removal of a gaseous mixture containing toluene,m-xylene,ethylbenzene,cyclohexane,butane,pentane,hexane and heptane in aerated stirred bioreactors inoculated with Rhodococcus erythropolis and operated under non-sterile conditions.For the real-time measurement of hydrocarbons,a novel systematic approachwas implemented using Selected-Ion Flow TubeMass Spectrometry(SIFTMS).The effect of the carbon source(~9.5 ppmv)on(i)the bioreactors’performance(BR1:dosed with only cyclohexane as a single hydrocarbon versus BR2:dosed with a mixture of the 8 hydrocarbons)and(ii)the evolution of microbial communities over time were investigated.The results showed that cyclohexane reached a maximum removal efficiency(RE)of 53%±4%in BR1.In BR2,almost complete removal of toluene,m-xylene and ethylbenzene,being the most water-soluble and easy-to-degrade carbon sources,was observed.REs below 32%were obtained for the remaining compounds.By exposing the microbial consortium to only the five most recalcitrant hydrocarbons,REs between 45%±5%and 98%±1%were reached.In addition,we observed that airborne microorganisms populated the bioreactors and that the type of carbon source influenced the microbial communities developed.The abundance of species belonging to the genus Rhodococcus was below 10%in all bioreactors at the end of the experiments.This work provides fundamental insights to understand the complex behavior of gaseous hydrocarbon mixtures in bioreactors,along with a systematic approach for the development of SIFT-MS methods.展开更多
Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have con...Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses.展开更多
Background:Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes.The effect on markers of health and disease,such as offspring telomere length...Background:Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes.The effect on markers of health and disease,such as offspring telomere length(TL)and mitochondrial DNA content(mtDNAc)is unknown.Objectives:We assessed the efficacy of maternal multiple micronutrient(MMN)-fortified balanced-energy protein(BEP)and iron-folic acid(IFA)supplementation on newborn TL as a secondary outcome and mtDNAc as a non-declared outcome.Design:We conducted a randomized controlled trial in rural Burkina Faso,among pregnant females(15-40 years old)enrolled at<21 weeks of gestation.Mothers received either MMN-fortified BEP and IFA(intervention)or IFA only(control)throughout pregnancy.Whole arterial blood samples were collected from the umbilical cord of 104 control and 90 intervention group infants,respectively.Average relative TL and mtDNAc were measured using quantitative polymerase chain reaction.Linear regression models were fitted to assess TL and mtDNAc differences across trial arms.Results:We found that a combined daily MMN-fortified BEP supplement and IFA tablet did not affect newborn TL[β=-0.010(95%CI:-0.057,0.036);P=0.662]or mtDNAc[β=0.065(95%CI:-0.203,0.073);P=0.354],as compared to an IFA tablet alone.These findings were confirmed(P>0.05)by adjusting the regression models for potential prognostic factors of study outcomes at enrollment.Exploratory analyses indicated higher,but non-significantly different mtDNAc among children born either small-for-gestational age,low birthweight,or preterm.Conclusion:Newborns from mothers who received daily nutritional supplements across gestation did not have different relative TL or mtDNAc.展开更多
Chemical engineers rely on models for design,research,and daily decision-making,often with potentially large financial and safety implications.Previous efforts a few decades ago to combine artificial intelligence and ...Chemical engineers rely on models for design,research,and daily decision-making,often with potentially large financial and safety implications.Previous efforts a few decades ago to combine artificial intelligence and chemical engineering for modeling were unable to fulfill the expectations.In the last five years,the increasing availability of data and computational resources has led to a resurgence in machine learning-based research.Many recent efforts have facilitated the roll-out of machine learning techniques in the research field by developing large databases,benchmarks,and representations for chemical applications and new machine learning frameworks.Machine learning has significant advantages over traditional modeling techniques,including flexibility,accuracy,and execution speed.These strengths also come with weaknesses,such as the lack of interpretability of these black-box models.The greatest opportunities involve using machine learning in time-limited applications such as real-time optimization and planning that require high accuracy and that can build on models with a self-learning ability to recognize patterns,learn from data,and become more intelligent over time.The greatest threat in artificial intelligence research today is inappropriate use because most chemical engineers have had limited training in computer science and data analysis.Nevertheless,machine learning will definitely become a trustworthy element in the modeling toolbox of chemical engineers.展开更多
Background: Weaning is known to result in barrier dysfunction and villus atrophy in the immediate post-weaning phase, and the magnitude of these responses is hypothesized to correlate with changes in the glutathione(G...Background: Weaning is known to result in barrier dysfunction and villus atrophy in the immediate post-weaning phase, and the magnitude of these responses is hypothesized to correlate with changes in the glutathione(GSH)redox system. Therefore, these parameters were simultaneously measured throughout the weaning phase, in piglets differing in birth weight category and weaning age, as these pre-weaning factors are important determinants for the weaning transition. Low birth weight(LBW) and normal birth weight(NBW) littermates were assigned to one of three weaning treatments;i.e. weaning at 3 weeks of age(3 w), weaning at 4 weeks of age(4 w) and removal from the sow at 3 d of age and fed a milk replacer until weaning at 3 weeks of age(3 d3 w). For each of these treatments, six LBW and six NBW piglets were euthanized at 0, 2, 5, 12 or 28 d post-weaning piglets, adding up 180 piglets.Results: Weaning increased the glutathione peroxidase activity on d 5 post-weaning in plasma, and duodenal and jejunal mucosa. Small intestinal glutathione-S-transferase activity gradually increased until d 12 post-weaning, and this was combined with a progressive rise of mucosal GSH up till d 12 post-weaning. Oxidation of the GSH redox status(GSH/GSSG Eh) was only observed in the small intestinal mucosa of 3 d3 w weaned piglets at d 5 postweaning. These piglets also demonstrated increased fluorescein isothiocyanate dextran(FD4) and horseradish peroxidase fluxes in the duodenum and distal jejunum during the experiment, and specifically demonstrated increased FD4 fluxes at d 2 to d 5 post-weaning. On the other hand, profound villus atrophy was observed during the weaning transition for all weaning treatments. Finally, LBW and NBW piglets did not demonstrate notable differences in GSH redox status, small intestinal barrier function and histo-morphology throughout the experiment.Conclusion: Although moderate changes in the GSH redox system were observed upon weaning, the GSH redox status remained at a steady state level in 3 w and 4 w weaned piglets and was therefore not associated with weaning induced villus atrophy. Conversely, 3 d3 w weaned piglets demonstrated GSH redox imbalance in the small intestinal mucosa, and this co-occurred with a temporal malfunction of their intestinal barrier function.展开更多
Understanding the impact of biological activities on the soil phosphorus(P)distribution under long-term fertilizer application can facilitate better soil P fertility management.Therefore,the primary objectives of this...Understanding the impact of biological activities on the soil phosphorus(P)distribution under long-term fertilizer application can facilitate better soil P fertility management.Therefore,the primary objectives of this study were to investigate the effect of long-term(since 1981)fertilizer application on the soil P fractions and microbial community and to evaluate correlations between the microbial community structure and P distribution.The following treatments were implemented in a long-term field trial:no fertilization(CK),inorganic N and K(NK),inorganic P and K(PK),inorganic N,P and K(NPK)and manure+NPK(MNPK)fertilization.The study showed that the soil pH,soil organic carbon and total and available N and P concentrations were considerably higher in the MNPK treatment than in the CK treatment.The soil microbial biomass C,N and P concentrations were also significantly higher in the MNPK treatment than in the CK treatment.Among fertilization treatments,theβ-1,4-glucosidase,α-1,4-glucosidase,urease,acid phosphatase and phosphodiesterase activities were the highest in the MNPK treatment.Compared to inorganic fertilization,the MNPK treatment increased the labile soil P fractions and decreased the residual soil P concentration.Continuous fertilization significantly affected the soil microbial composition.The total phospholipid fatty acid(PLFA)concentrations in the NK,PK,NPK and MNPK treatments were 23.3,43.1,48.7 and 87.7%higher,respectively,than in the CK treatment.A significant correlation was observed between the microbial community and soil P fractions.Moreover,the aggregated boosted tree(ABT)model showed that among the various soil biochemical properties,the total PLFA concentration was the factor that most influenced the active P pool,accounting for 35.4%of the relative influence of all soil biochemical properties examined.These findings reveal that combined manure and inorganic fertilizer application is a better approach than applying inorganic fertilizer alone for sustaining long-term P fertility by mediating soil biological activity.展开更多
The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins ...The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.展开更多
Background： In this study the physiological implications of artificial rearing were investigated. Low（LBW） and normal birth weight（NBW） piglets were compared as they might react differently to stressors caused by...Background： In this study the physiological implications of artificial rearing were investigated. Low（LBW） and normal birth weight（NBW） piglets were compared as they might react differently to stressors caused by artificial rearing. In total, 42 pairs of LBW and NBW piglets from 16 litters suckled the sow until d19 of age or were artificially reared starting at d3 until d19 of age. Blood and tissue samples that were collected after euthanasia at 0, 3, 5, 8 and 19 d of age. Histology, ELISA, and Ussing chamber analysis were used to study proximal and distal small intestine histomorphology, proliferation, apoptosis, tight junction protein expression, and permeability. Furthermore, small intestine,liver and systemic redox parameters（GSH, GSSG, GSH-Px and MDA） were investigated using HPLC.Results： LBW and NBW artificially reared piglets weighed respectively 40 and 33% more than LBW and NBW sowreared piglets at d19（P 〈 0.01）. Transferring piglets to a nursery at d3 resulted in villus atrophy, increased intestinal FD-4 and HRP permeability and elevated GSSG/GSH ratio in the distal small intestine at d5（P 〈 0.05）. GSH concentrations in the proximal small intestine remained stable, while they decreased in the liver（P 〈 0.05）. From d5 until d19, villus width and crypt depth increased, whereas PCNA, caspase-3, occludin and claudin-3 protein expressions were reduced. GSH,GSSG and permeability recovered in artificially reared piglets（P 〈 0.05）.Conclusion： The results suggest that artificial rearing altered the morphology, permeability and redox state without compromising piglet performance. The observed effects were not depending on birth weight.展开更多
Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack...Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.展开更多
Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility ...Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal microbiota.This was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6.Furthermore,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration.In the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows.Nevertheless,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN cows.Consistent with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was increased.Nevertheless,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups.Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the animals.Conclusions:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial communities.Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum.Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy.展开更多
Background: The EU ban on antimicrobial growth promoters (AGP) has initiated a search for non-antibiotic alternatives. It has been demonstrated that certain antibiotics and non-antibiotic alternatives enhance growth b...Background: The EU ban on antimicrobial growth promoters (AGP) has initiated a search for non-antibiotic alternatives. It has been demonstrated that certain antibiotics and non-antibiotic alternatives enhance growth by inhibiting inflammatory cells, i.e. neutrophils and macrophages in the intestine. There is very little information on the effect of anti-inflammatory compounds on intestinal epithelial cells, which are known to play an important role in intestinal inflammatory responses. In order to establish this, a porcine intestinal epithelial cell line (IPEC J2) was incubated with an adherent enterotoxigenic E. coli (ETEC) to stimulate inflammation, using a non-pathogenic non-adherent E. coli (EC) as a control. The influence of the presence of the anti-inflammatory compounds Macleaya cordata extract (MCE) and acetylsalicylic acid (ASA) on inflammatory transcriptional responses was studied. Results: ETEC induced a strong inflammatory response as was most evident from the expression of IL-1β, IL-8 and TNF-α, whereas EC induced IL-1βonly. Co-incubation with MCE and ASA significantly reduced the responses of the pro-inflammatory cytokines, similarly for IL-1βand TNF-α, but ASA was more effective than MCE in reducing the IL8 response. Conclusions: The present results suggest that the in vivo anti-inflammatory growth promoting effects of AGP and effective alternatives to AGP such as MCE and ASA are not restricted to inflammatory cells and also involve the more abundant enterocytes. This suggests a major role for epithelial cells in growth promotion livestock, and it further supports the notion that effective alternatives to AGP should have anti-inflammatory activity.展开更多
Recently, near infrared reflectance （NIR） and mid-infrared （MIR） spectroscopy techniques are increasingly introduced as convenient and simple non-destructive techniques for quantifying several soil properties. Thi...Recently, near infrared reflectance （NIR） and mid-infrared （MIR） spectroscopy techniques are increasingly introduced as convenient and simple non-destructive techniques for quantifying several soil properties. This study uses MIR method to predict pH, soil organic C, total N, AI, Ca, Mg and K, CEC and soil texture for soil samples collected in Sud-Kivu, Congo. A total of 536 composite soil samples were taken from two locations （Burhale and Luhihi） at two depths （0-20 cm and 20-40 cm） using a spatially-stratified random sampling design within an area of 200 km2. Differences in characteristics were evaluated between the two locations, land use （cultivated vs. non-cultivated land） with soil depths. A random subset of the samples （10%） were analyzed using standard wet chemistry methods, and calibration models developed by MIR data to estimate soil properties for the full soil sample set. Partial least squares regression （PLS） method gave acceptable coefficients of determination between 0.71 and 0.93 for all parameters. Soil organic matter levels were higher in cultivated plots in Luhihi （3.9% C） than in Burhale （3.0% C）, suggesting lower levels of soil fertility in the later area. This indicates high levels of acidity, which are likely to limit crop production in the area. Phosphorus deficiency is acute in Burhale （2.4 mg P/kg） but less in Luhihi （5.4 mg P/kg）. In both locations, low levels of Ca and Mg indicate that soils may be susceptible to deficiencies in both elements.These findings provide new opportunities for monitoring soil quality in the region which can benefit multiple actors and scientists involved in the agricultural and environmental sectors.展开更多
Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after in...Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after independence has resulted into erosion of its communities’ conservation behaviour and attitude. Although many studies assess environmental attitudes, those focussing on African regions or countries using New Environmental Paradigm (NEP) scale are very limited. Such studies in the African context using NEP scale are very important, simply because many people depend on the environment for their livelihood, and in the process they destroy the world’s valued ecosystems including wetlands. This study is meant to fill in the gap using Kilombero valley wetlands in Tanzania as a case. The study used Structural Equation Modelling (SEM) to predict the behaviour of the users based on attitudes, environmental knowledge and awareness. The findings indicate that users of the Kilombero wetlands have a generally positive attitude towards the environment, despite a great degree of variability among the study participants. The study shows also that a certain level of environmental awareness is needed in order to increase people’s knowledge about environmental issues and change their environmental attitudes. The NEP scale does not fully fit into the Tanzanian context, thus suggesting that further research into the adaptation of the scale is needed.展开更多
Phytoextraction has been introduced as a new technology to clean up soils contaminated with heavy metals as the use of conventional methods to clean up the soil is very expensive and destructive to the ecosystem. Howe...Phytoextraction has been introduced as a new technology to clean up soils contaminated with heavy metals as the use of conventional methods to clean up the soil is very expensive and destructive to the ecosystem. However, using plants to clean up contaminated soils takes a considerable period before the contaminants are removed from the soil by the plants. This has necessitated the use of amendments to enhance phytoextraction in order to shorten the period of contaminants removal by plants. In view of this, a pot experiment was conducted to study the effect of various aminopolycarboxylic acids (EDTA, EDDS, NTA dry and NTA liquid) and two commercial fertilizers which are Hortrilon? and Fetrilon? on their ability to solubilize Cd and Zn in contaminated soils. It was observed that the inducing effect of EDTA on the solubility of Cd and Zn persisted throughout the experimental period. Initially, EDDS enhanced the solubility Cd and Zn, however, its effect dissipated with time. The application of both NTA dry (powder) and NTA liquid had a significant effect on the solubility of Zn as a result of the formation of Zn-NTA soluble complexes. Hortrilon? and Fetrilon? solubilized significant concentrations of both Cd and Zn with Hortrilon? having the greatest inducing effect on the solubility of Cd and Zn.展开更多
Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical fores...Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree species.However,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in detail.Terrestrial laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented way.Therefore,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest structure.These plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition levels.We generated vertical plant profiles from the TLS data and derived six stand structural variables.Linear mixed models were used to test the effect of species richness on structural variables.Employing a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural variables.Our results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height diversity.Species identity on the other hand exhibited a significant impact on vertical forest structure across all sites.Species interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these interactions.Overall,our results highlighted the importance of considering both species identity and interaction effects in choosing suitable species combinations for forest management practices aimed at enhancing vertical forest structure.展开更多
Changes in the quality of eggs during storage relate to their shelf life and economic value.factors such as temperature,relative humidity,the operation of cleaning and microorganisms have been shown to play a role in ...Changes in the quality of eggs during storage relate to their shelf life and economic value.factors such as temperature,relative humidity,the operation of cleaning and microorganisms have been shown to play a role in the storage quality of eggs.This study thus aimed at investigating the effect of hen age on the storage quality of egg,and predicting egg shelf life using back propagation artificial neural network(bP-aNN)based models.Eggs laid by Jingfen No.1(27 and 58 weeks of age)and Jingfen No.6(26 and 57 weeks of age)hens were stored under ambient conditions and evaluated by physicochemical properties.it was found that the shelf life of the lower age group was significantly longer than that of the higher age group.a novel hybrid model combining bP-aNN,cuckoo search and adaptive boosting(Cs-bP-adaboost)was proposed for predicting the remaining egg shelf life,with the input being Haugh unit,yolk index,air cell depth,albumen pH,hen age and breed.The tuning process of hyperparameters such as learning rate,training function,and transfer function was presented in detail.results show that Cs-bP-adaboost had satisfactory performance on the test set with root mean square error(rMsE)and coefficient of determination(R^(2))of 0.68 and 0.97,respectively.and it outperformed bP-aNN by reducing rMsE by 0.39 and improving R^(2) by 0.05.The model used solved the problem that the traditional bP-aNN tends to fall into local minima.The removal of hen age from the input parameters caused a decrease in prediction accuracy(R2=0.95,rMsE=1.00),suggesting an important role of hen age in shelf life prediction.This study demonstrates the great potential of applying combinatorial modeling approaches to predict egg shelf life and the crucial impact of hen age on egg shelf life prediction.展开更多
Gold(Au)nanostructures(NSs)have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials,while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-f...Gold(Au)nanostructures(NSs)have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials,while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-fuel conversion efficiency is still lacking.In this review,the recently developed strategies for elevating the overall photocatalytic performance of Au-based catalysts and the deep physical chemistry mechanisms are highlighted.Firstly,the synthetic approaches of Au NSs are summarized,followed by an elaboration on their multiple functions in improving photoactivity.Afterward,modification strategies of Au NSs used to enhance the photocatalytic efficiency of Au-semiconductor composites,including controlling the Au NSs morphology,size,crystal phase,defect engineering,alloying with different metals,modulating interfacial interaction,and introducing an external field,are summarized and discussed independently.Additionally,advanced characterization techniques that can provide insights into the charge dynamics of the photocatalysts are introduced.Finally,we share our opinion on the challenges and outline potentially promising opportunities and directions for efficient Au-based photocatalysis research moving forward.We sincerely look forward to this review can deliver insightful views to design efficient Au-based photocatalysts and spur certain innovations to other metal-based catalysts.展开更多
Concern for individual perception is essential to enhance greenspace management.Various landscape elements are key factors affecting visitors’perception engaging in greenspaces.Targeting Belgian public greenspaces,we...Concern for individual perception is essential to enhance greenspace management.Various landscape elements are key factors affecting visitors’perception engaging in greenspaces.Targeting Belgian public greenspaces,we develop a comprehensive approach to quantify visitors’perceptions from multiple dimensions.Applying user-generated data and unsupervised machine learning approach,we identified the landscape elements and classified the greenspaces to extract perception rates and detect dominant elements.The satisfaction of every landscape element was then analyzed by the natural language process approach and standardized major axis regression to discover their contributions to overall satisfaction.Furthermore,we calculated and visualized the positive and negative interactions between elements through network analysis.Integrating the perception rates and contributions,inconsistency was observed between the dominant element and the most contributing element.The perception rate of the human element was in an overwhelmingly dominant position,with 2.46.Despite the variations among the 5 greenspace groups,multiple natural elements highly contributed to overall satisfaction,especially animal and vegetation,which achieved contributions higher than 1.2 in most of the groups.Regarding the interactions,stronger negative interactions appeared generally,reaching up to 0.496.The coexistence of natural and artificial elements has a stronger collective effect on greenspace perception,regardless of positive or negative interaction.By providing an understanding of the landscape elements,our findings can assist greenspace planners in identifying key factors of different greenspace categories from various perspectives and support explicit and effective greenspace management.展开更多
基金supported by Ghent University through a special research grant(No.BOFSTG2019005701)The assistance provided by Ann Dirckx in the microbiology lab was greatly appreciated.Allan A.Alvarado-Alvarado thanks the European Commission under the Erasmus+EMJMD Program for funding his research at Ghent University(No.2017-1957/001-001-EMJMD).
文摘The study of microbial hydrocarbons removal is of great importance for the development of future bioremediation strategies.In this study,we evaluated the removal of a gaseous mixture containing toluene,m-xylene,ethylbenzene,cyclohexane,butane,pentane,hexane and heptane in aerated stirred bioreactors inoculated with Rhodococcus erythropolis and operated under non-sterile conditions.For the real-time measurement of hydrocarbons,a novel systematic approachwas implemented using Selected-Ion Flow TubeMass Spectrometry(SIFTMS).The effect of the carbon source(~9.5 ppmv)on(i)the bioreactors’performance(BR1:dosed with only cyclohexane as a single hydrocarbon versus BR2:dosed with a mixture of the 8 hydrocarbons)and(ii)the evolution of microbial communities over time were investigated.The results showed that cyclohexane reached a maximum removal efficiency(RE)of 53%±4%in BR1.In BR2,almost complete removal of toluene,m-xylene and ethylbenzene,being the most water-soluble and easy-to-degrade carbon sources,was observed.REs below 32%were obtained for the remaining compounds.By exposing the microbial consortium to only the five most recalcitrant hydrocarbons,REs between 45%±5%and 98%±1%were reached.In addition,we observed that airborne microorganisms populated the bioreactors and that the type of carbon source influenced the microbial communities developed.The abundance of species belonging to the genus Rhodococcus was below 10%in all bioreactors at the end of the experiments.This work provides fundamental insights to understand the complex behavior of gaseous hydrocarbon mixtures in bioreactors,along with a systematic approach for the development of SIFT-MS methods.
基金The research that yielded these results,was funded by the Belgian Federal Public Service of Health,Food Chain Safety and Environment through the contract RF 17/6314 LactoPigHealthMatthias Dierick is supported by the Flemish fund for scientific research(FWO3S036319).
文摘Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses.
基金supported by the Bill&Melinda Gates Foundation(OPP1175213)supported by the Research Foundation Flanders(12X9620N and 12X9623N)the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(946192,HUMYCO)。
文摘Background:Evidence regarding the effectiveness of prenatal nutritional supplements has mainly considered anthropometric pregnancy outcomes.The effect on markers of health and disease,such as offspring telomere length(TL)and mitochondrial DNA content(mtDNAc)is unknown.Objectives:We assessed the efficacy of maternal multiple micronutrient(MMN)-fortified balanced-energy protein(BEP)and iron-folic acid(IFA)supplementation on newborn TL as a secondary outcome and mtDNAc as a non-declared outcome.Design:We conducted a randomized controlled trial in rural Burkina Faso,among pregnant females(15-40 years old)enrolled at<21 weeks of gestation.Mothers received either MMN-fortified BEP and IFA(intervention)or IFA only(control)throughout pregnancy.Whole arterial blood samples were collected from the umbilical cord of 104 control and 90 intervention group infants,respectively.Average relative TL and mtDNAc were measured using quantitative polymerase chain reaction.Linear regression models were fitted to assess TL and mtDNAc differences across trial arms.Results:We found that a combined daily MMN-fortified BEP supplement and IFA tablet did not affect newborn TL[β=-0.010(95%CI:-0.057,0.036);P=0.662]or mtDNAc[β=0.065(95%CI:-0.203,0.073);P=0.354],as compared to an IFA tablet alone.These findings were confirmed(P>0.05)by adjusting the regression models for potential prognostic factors of study outcomes at enrollment.Exploratory analyses indicated higher,but non-significantly different mtDNAc among children born either small-for-gestational age,low birthweight,or preterm.Conclusion:Newborns from mothers who received daily nutritional supplements across gestation did not have different relative TL or mtDNAc.
基金The authors acknowledge funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation(818607)Pieter P.Plehiers and Ruben Van de Vijver acknowledge financial support,respectively,from a doctoral(1150817N)a postdoctoral(3E013419)fellowship from the Research Foundation-Flanders(FWO).
文摘Chemical engineers rely on models for design,research,and daily decision-making,often with potentially large financial and safety implications.Previous efforts a few decades ago to combine artificial intelligence and chemical engineering for modeling were unable to fulfill the expectations.In the last five years,the increasing availability of data and computational resources has led to a resurgence in machine learning-based research.Many recent efforts have facilitated the roll-out of machine learning techniques in the research field by developing large databases,benchmarks,and representations for chemical applications and new machine learning frameworks.Machine learning has significant advantages over traditional modeling techniques,including flexibility,accuracy,and execution speed.These strengths also come with weaknesses,such as the lack of interpretability of these black-box models.The greatest opportunities involve using machine learning in time-limited applications such as real-time optimization and planning that require high accuracy and that can build on models with a self-learning ability to recognize patterns,learn from data,and become more intelligent over time.The greatest threat in artificial intelligence research today is inappropriate use because most chemical engineers have had limited training in computer science and data analysis.Nevertheless,machine learning will definitely become a trustworthy element in the modeling toolbox of chemical engineers.
基金supported by a grant from the government agency for Innovation by Science and Technology (IWT-LO 100856)。
文摘Background: Weaning is known to result in barrier dysfunction and villus atrophy in the immediate post-weaning phase, and the magnitude of these responses is hypothesized to correlate with changes in the glutathione(GSH)redox system. Therefore, these parameters were simultaneously measured throughout the weaning phase, in piglets differing in birth weight category and weaning age, as these pre-weaning factors are important determinants for the weaning transition. Low birth weight(LBW) and normal birth weight(NBW) littermates were assigned to one of three weaning treatments;i.e. weaning at 3 weeks of age(3 w), weaning at 4 weeks of age(4 w) and removal from the sow at 3 d of age and fed a milk replacer until weaning at 3 weeks of age(3 d3 w). For each of these treatments, six LBW and six NBW piglets were euthanized at 0, 2, 5, 12 or 28 d post-weaning piglets, adding up 180 piglets.Results: Weaning increased the glutathione peroxidase activity on d 5 post-weaning in plasma, and duodenal and jejunal mucosa. Small intestinal glutathione-S-transferase activity gradually increased until d 12 post-weaning, and this was combined with a progressive rise of mucosal GSH up till d 12 post-weaning. Oxidation of the GSH redox status(GSH/GSSG Eh) was only observed in the small intestinal mucosa of 3 d3 w weaned piglets at d 5 postweaning. These piglets also demonstrated increased fluorescein isothiocyanate dextran(FD4) and horseradish peroxidase fluxes in the duodenum and distal jejunum during the experiment, and specifically demonstrated increased FD4 fluxes at d 2 to d 5 post-weaning. On the other hand, profound villus atrophy was observed during the weaning transition for all weaning treatments. Finally, LBW and NBW piglets did not demonstrate notable differences in GSH redox status, small intestinal barrier function and histo-morphology throughout the experiment.Conclusion: Although moderate changes in the GSH redox system were observed upon weaning, the GSH redox status remained at a steady state level in 3 w and 4 w weaned piglets and was therefore not associated with weaning induced villus atrophy. Conversely, 3 d3 w weaned piglets demonstrated GSH redox imbalance in the small intestinal mucosa, and this co-occurred with a temporal malfunction of their intestinal barrier function.
基金supported by the National Key Research and Development Program of China(2016YFD0300901)the Fundamental Research Funds for Central Nonprofit Scientific Institutions of China(1610132019035,1610132020023 and 1610132020024)the Natural Science Foundation of Jiangxi Province,China(20192BAB203022)。
文摘Understanding the impact of biological activities on the soil phosphorus(P)distribution under long-term fertilizer application can facilitate better soil P fertility management.Therefore,the primary objectives of this study were to investigate the effect of long-term(since 1981)fertilizer application on the soil P fractions and microbial community and to evaluate correlations between the microbial community structure and P distribution.The following treatments were implemented in a long-term field trial:no fertilization(CK),inorganic N and K(NK),inorganic P and K(PK),inorganic N,P and K(NPK)and manure+NPK(MNPK)fertilization.The study showed that the soil pH,soil organic carbon and total and available N and P concentrations were considerably higher in the MNPK treatment than in the CK treatment.The soil microbial biomass C,N and P concentrations were also significantly higher in the MNPK treatment than in the CK treatment.Among fertilization treatments,theβ-1,4-glucosidase,α-1,4-glucosidase,urease,acid phosphatase and phosphodiesterase activities were the highest in the MNPK treatment.Compared to inorganic fertilization,the MNPK treatment increased the labile soil P fractions and decreased the residual soil P concentration.Continuous fertilization significantly affected the soil microbial composition.The total phospholipid fatty acid(PLFA)concentrations in the NK,PK,NPK and MNPK treatments were 23.3,43.1,48.7 and 87.7%higher,respectively,than in the CK treatment.A significant correlation was observed between the microbial community and soil P fractions.Moreover,the aggregated boosted tree(ABT)model showed that among the various soil biochemical properties,the total PLFA concentration was the factor that most influenced the active P pool,accounting for 35.4%of the relative influence of all soil biochemical properties examined.These findings reveal that combined manure and inorganic fertilizer application is a better approach than applying inorganic fertilizer alone for sustaining long-term P fertility by mediating soil biological activity.
文摘The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.
基金supported by a grant from the government agency for Innovation by Science and Technology(IWT-LO 100856)
文摘Background： In this study the physiological implications of artificial rearing were investigated. Low（LBW） and normal birth weight（NBW） piglets were compared as they might react differently to stressors caused by artificial rearing. In total, 42 pairs of LBW and NBW piglets from 16 litters suckled the sow until d19 of age or were artificially reared starting at d3 until d19 of age. Blood and tissue samples that were collected after euthanasia at 0, 3, 5, 8 and 19 d of age. Histology, ELISA, and Ussing chamber analysis were used to study proximal and distal small intestine histomorphology, proliferation, apoptosis, tight junction protein expression, and permeability. Furthermore, small intestine,liver and systemic redox parameters（GSH, GSSG, GSH-Px and MDA） were investigated using HPLC.Results： LBW and NBW artificially reared piglets weighed respectively 40 and 33% more than LBW and NBW sowreared piglets at d19（P 〈 0.01）. Transferring piglets to a nursery at d3 resulted in villus atrophy, increased intestinal FD-4 and HRP permeability and elevated GSSG/GSH ratio in the distal small intestine at d5（P 〈 0.05）. GSH concentrations in the proximal small intestine remained stable, while they decreased in the liver（P 〈 0.05）. From d5 until d19, villus width and crypt depth increased, whereas PCNA, caspase-3, occludin and claudin-3 protein expressions were reduced. GSH,GSSG and permeability recovered in artificially reared piglets（P 〈 0.05）.Conclusion： The results suggest that artificial rearing altered the morphology, permeability and redox state without compromising piglet performance. The observed effects were not depending on birth weight.
基金supported by the European Commission under the Interreg IVb NWE Project Arbor(No.Interreg IVB 223G)the Environmental&Energy Technology Innovation Platform(MIP),Belgium+2 种基金the Natural Science and Engineering Research Council of Canada(NSERC)the Fonds de Recherche de Québec sur la Nature et les Technologies(FRQNT),CanadaPrimodal Inc.,Hamilton,Canada
文摘Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and CaCl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.
基金the financial support of Flanders Innovation&Entrepreneurship(VLAIOBelgium+3 种基金LA170830)the European Union’s Horizon 2020 research and innovation programme under grant agreement 101000213-Holo RuminantThe PhD research of Hong Yang and Xiaoping Jing was the Chinese Scholarship Council(CSC,China)the PhD research of Stijn Heirbaut was funded by a Ph D grant from the Special Research Fund of the Ghent University(Bijzonder Onderzoeksfonds,BOF,Belgium)。
文摘Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal microbiota.This was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6.Furthermore,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration.In the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows.Nevertheless,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN cows.Consistent with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was increased.Nevertheless,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups.Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the animals.Conclusions:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial communities.Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum.Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy.
文摘Background: The EU ban on antimicrobial growth promoters (AGP) has initiated a search for non-antibiotic alternatives. It has been demonstrated that certain antibiotics and non-antibiotic alternatives enhance growth by inhibiting inflammatory cells, i.e. neutrophils and macrophages in the intestine. There is very little information on the effect of anti-inflammatory compounds on intestinal epithelial cells, which are known to play an important role in intestinal inflammatory responses. In order to establish this, a porcine intestinal epithelial cell line (IPEC J2) was incubated with an adherent enterotoxigenic E. coli (ETEC) to stimulate inflammation, using a non-pathogenic non-adherent E. coli (EC) as a control. The influence of the presence of the anti-inflammatory compounds Macleaya cordata extract (MCE) and acetylsalicylic acid (ASA) on inflammatory transcriptional responses was studied. Results: ETEC induced a strong inflammatory response as was most evident from the expression of IL-1β, IL-8 and TNF-α, whereas EC induced IL-1βonly. Co-incubation with MCE and ASA significantly reduced the responses of the pro-inflammatory cytokines, similarly for IL-1βand TNF-α, but ASA was more effective than MCE in reducing the IL8 response. Conclusions: The present results suggest that the in vivo anti-inflammatory growth promoting effects of AGP and effective alternatives to AGP such as MCE and ASA are not restricted to inflammatory cells and also involve the more abundant enterocytes. This suggests a major role for epithelial cells in growth promotion livestock, and it further supports the notion that effective alternatives to AGP should have anti-inflammatory activity.
文摘Recently, near infrared reflectance （NIR） and mid-infrared （MIR） spectroscopy techniques are increasingly introduced as convenient and simple non-destructive techniques for quantifying several soil properties. This study uses MIR method to predict pH, soil organic C, total N, AI, Ca, Mg and K, CEC and soil texture for soil samples collected in Sud-Kivu, Congo. A total of 536 composite soil samples were taken from two locations （Burhale and Luhihi） at two depths （0-20 cm and 20-40 cm） using a spatially-stratified random sampling design within an area of 200 km2. Differences in characteristics were evaluated between the two locations, land use （cultivated vs. non-cultivated land） with soil depths. A random subset of the samples （10%） were analyzed using standard wet chemistry methods, and calibration models developed by MIR data to estimate soil properties for the full soil sample set. Partial least squares regression （PLS） method gave acceptable coefficients of determination between 0.71 and 0.93 for all parameters. Soil organic matter levels were higher in cultivated plots in Luhihi （3.9% C） than in Burhale （3.0% C）, suggesting lower levels of soil fertility in the later area. This indicates high levels of acidity, which are likely to limit crop production in the area. Phosphorus deficiency is acute in Burhale （2.4 mg P/kg） but less in Luhihi （5.4 mg P/kg）. In both locations, low levels of Ca and Mg indicate that soils may be susceptible to deficiencies in both elements.These findings provide new opportunities for monitoring soil quality in the region which can benefit multiple actors and scientists involved in the agricultural and environmental sectors.
文摘Development policies have for a long time made it more profitable for people to degrade than to conserve environment. The adoption of these economic wide policies by Africa especially during colonial time and after independence has resulted into erosion of its communities’ conservation behaviour and attitude. Although many studies assess environmental attitudes, those focussing on African regions or countries using New Environmental Paradigm (NEP) scale are very limited. Such studies in the African context using NEP scale are very important, simply because many people depend on the environment for their livelihood, and in the process they destroy the world’s valued ecosystems including wetlands. This study is meant to fill in the gap using Kilombero valley wetlands in Tanzania as a case. The study used Structural Equation Modelling (SEM) to predict the behaviour of the users based on attitudes, environmental knowledge and awareness. The findings indicate that users of the Kilombero wetlands have a generally positive attitude towards the environment, despite a great degree of variability among the study participants. The study shows also that a certain level of environmental awareness is needed in order to increase people’s knowledge about environmental issues and change their environmental attitudes. The NEP scale does not fully fit into the Tanzanian context, thus suggesting that further research into the adaptation of the scale is needed.
文摘Phytoextraction has been introduced as a new technology to clean up soils contaminated with heavy metals as the use of conventional methods to clean up the soil is very expensive and destructive to the ecosystem. However, using plants to clean up contaminated soils takes a considerable period before the contaminants are removed from the soil by the plants. This has necessitated the use of amendments to enhance phytoextraction in order to shorten the period of contaminants removal by plants. In view of this, a pot experiment was conducted to study the effect of various aminopolycarboxylic acids (EDTA, EDDS, NTA dry and NTA liquid) and two commercial fertilizers which are Hortrilon? and Fetrilon? on their ability to solubilize Cd and Zn in contaminated soils. It was observed that the inducing effect of EDTA on the solubility of Cd and Zn persisted throughout the experimental period. Initially, EDDS enhanced the solubility Cd and Zn, however, its effect dissipated with time. The application of both NTA dry (powder) and NTA liquid had a significant effect on the solubility of Zn as a result of the formation of Zn-NTA soluble complexes. Hortrilon? and Fetrilon? solubilized significant concentrations of both Cd and Zn with Hortrilon? having the greatest inducing effect on the solubility of Cd and Zn.
基金Mengxi Wang holds a doctoral scholarship from the China scholarship council(CSC:202003270025)。
文摘Vertical forest structure is closely linked to multiple ecosystem characteristics,such as biodiversity,habitat,and productivity.Mixing tree species in planted forests has the potential to create diverse vertical forest structures due to the different physiological and morphological traits of the composing tree species.However,the relative importance of species richness,species identity and species interactions for the variation in vertical forest structure remains unclear,mainly because traditional forest inventories do not observe vertical stand structure in detail.Terrestrial laser scanning(TLS),however,allows to study vertical forest structure in an unprecedented way.Therefore,we used TLS single scan data from 126 plots across three experimental planted forests of a largescale tree diversity experiment in Belgium to study the drivers of vertical forest structure.These plots were 9–11years old young pure and mixed forests,characterized by four levels of tree species richness ranging from monocultures to four-species mixtures,across twenty composition levels.We generated vertical plant profiles from the TLS data and derived six stand structural variables.Linear mixed models were used to test the effect of species richness on structural variables.Employing a hierarchical diversity interaction modelling framework,we further assessed species identity effect and various species interaction effects on the six stand structural variables.Our results showed that species richness did not significantly influence most of the stand structure variables,except for canopy height and foliage height diversity.Species identity on the other hand exhibited a significant impact on vertical forest structure across all sites.Species interaction effects were observed to be site-dependent due to varying site conditions and species pools,and rapidly growing tree species tend to dominate these interactions.Overall,our results highlighted the importance of considering both species identity and interaction effects in choosing suitable species combinations for forest management practices aimed at enhancing vertical forest structure.
基金supported by the Key scientific and Technological research Projects of Xinjiang Production and Construction Corps(2022ab001)the National Natural science foundation of China(32272252)+1 种基金Wens fifth five R&D Major Project(WENs-2020-1-ZDZX-007)China scholarship Council(CsC)for the scholarship under the Grant CsC No.202006150027.
文摘Changes in the quality of eggs during storage relate to their shelf life and economic value.factors such as temperature,relative humidity,the operation of cleaning and microorganisms have been shown to play a role in the storage quality of eggs.This study thus aimed at investigating the effect of hen age on the storage quality of egg,and predicting egg shelf life using back propagation artificial neural network(bP-aNN)based models.Eggs laid by Jingfen No.1(27 and 58 weeks of age)and Jingfen No.6(26 and 57 weeks of age)hens were stored under ambient conditions and evaluated by physicochemical properties.it was found that the shelf life of the lower age group was significantly longer than that of the higher age group.a novel hybrid model combining bP-aNN,cuckoo search and adaptive boosting(Cs-bP-adaboost)was proposed for predicting the remaining egg shelf life,with the input being Haugh unit,yolk index,air cell depth,albumen pH,hen age and breed.The tuning process of hyperparameters such as learning rate,training function,and transfer function was presented in detail.results show that Cs-bP-adaboost had satisfactory performance on the test set with root mean square error(rMsE)and coefficient of determination(R^(2))of 0.68 and 0.97,respectively.and it outperformed bP-aNN by reducing rMsE by 0.39 and improving R^(2) by 0.05.The model used solved the problem that the traditional bP-aNN tends to fall into local minima.The removal of hen age from the input parameters caused a decrease in prediction accuracy(R2=0.95,rMsE=1.00),suggesting an important role of hen age in shelf life prediction.This study demonstrates the great potential of applying combinatorial modeling approaches to predict egg shelf life and the crucial impact of hen age on egg shelf life prediction.
基金financially supported by the National Natural Science Foundation of China(21902132)the Research Foundation-Flanders(1280021N,1242922N,1298323N)。
文摘Gold(Au)nanostructures(NSs)have been widely employed as cocatalysts to improve the photoactivity of semiconductor materials,while a systematic summary of the engineering approaches of Au NSs to maximize the solar-to-fuel conversion efficiency is still lacking.In this review,the recently developed strategies for elevating the overall photocatalytic performance of Au-based catalysts and the deep physical chemistry mechanisms are highlighted.Firstly,the synthetic approaches of Au NSs are summarized,followed by an elaboration on their multiple functions in improving photoactivity.Afterward,modification strategies of Au NSs used to enhance the photocatalytic efficiency of Au-semiconductor composites,including controlling the Au NSs morphology,size,crystal phase,defect engineering,alloying with different metals,modulating interfacial interaction,and introducing an external field,are summarized and discussed independently.Additionally,advanced characterization techniques that can provide insights into the charge dynamics of the photocatalysts are introduced.Finally,we share our opinion on the challenges and outline potentially promising opportunities and directions for efficient Au-based photocatalysis research moving forward.We sincerely look forward to this review can deliver insightful views to design efficient Au-based photocatalysts and spur certain innovations to other metal-based catalysts.
基金funded by the China Scholarship Council(grant number:202004910422)
文摘Concern for individual perception is essential to enhance greenspace management.Various landscape elements are key factors affecting visitors’perception engaging in greenspaces.Targeting Belgian public greenspaces,we develop a comprehensive approach to quantify visitors’perceptions from multiple dimensions.Applying user-generated data and unsupervised machine learning approach,we identified the landscape elements and classified the greenspaces to extract perception rates and detect dominant elements.The satisfaction of every landscape element was then analyzed by the natural language process approach and standardized major axis regression to discover their contributions to overall satisfaction.Furthermore,we calculated and visualized the positive and negative interactions between elements through network analysis.Integrating the perception rates and contributions,inconsistency was observed between the dominant element and the most contributing element.The perception rate of the human element was in an overwhelmingly dominant position,with 2.46.Despite the variations among the 5 greenspace groups,multiple natural elements highly contributed to overall satisfaction,especially animal and vegetation,which achieved contributions higher than 1.2 in most of the groups.Regarding the interactions,stronger negative interactions appeared generally,reaching up to 0.496.The coexistence of natural and artificial elements has a stronger collective effect on greenspace perception,regardless of positive or negative interaction.By providing an understanding of the landscape elements,our findings can assist greenspace planners in identifying key factors of different greenspace categories from various perspectives and support explicit and effective greenspace management.
