Improving dryland maize productivity and water efficiency with heterotrophic ammonia-oxidizing bacteria via nitrification and cytokinin activity

A two-year field experiment conducted under dryland conditions in semi-humid and drought-prone regions of China aimed to assess the effect of ammonia-oxidizing bacterial on maize water use efficiency and yield.A heterotrophic ammonia-oxidizing bacteria(HAOB)strain S2_8_1 was used.Six treatments were applied:(1)no irrigation+HAOB strain(DI),(2)no irrigation+blank culture medium(DM),(3)no irrigation control(DCK),(4)irrigation+HAOB(WI),(5)irrigation+blank culture medium(WM),and(6)irrigation control(WCK).Results revealed that HAOB treatment increased maize growth,yield,and water use efficiency over controls,regardless of whether the year was wet or dry.This improvement was attributed to the accelerated nitrification in the rhizosphere soil due to HAOB inoculation,which subsequently led to increased levels of leaf cytokinins.Overall,these findings suggest that HAOB inoculation holds promise as a strategy to boost water use efficiency and maize productivity in dryland agriculture.

Dendritic spine degeneration:a primary mechanism in the aging process

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

Effects of Transgenic DREB Soybean Dongnong 50 on the Diversity of Soil Ammonia-oxidizing Bacteria

ObjectiveThe aim was to understand the effects of transgenic DREB soybean on the ammonia-oxidizing bacteria. MethodThe diversity of the cto gene in pot-planted transgenic soybean and near-isogenic non-transgenic soybean under normal water condition and drought stress was analyzed by PCR-DGGE and sequence analysis. ResultRhizosphere community diversity of ammonia-oxidizing bacteria showed no difference between the treatments of transgenic soybean and its non-transgenic isolines, moreover transgenic soybean under normal water condition and drought stress improved the diversity of the ammonia-oxidizing bacteria in the harvest time. The phylogenetic analysis revealed that all the sequences of excised DGGE bands were closely related to members of the genus Nitrosovibrio and Nitrosospira of the β-subclass Proteobacteria. ConclusionTransgenic DREB soybean has no adverse impact on soil ammonia-oxidizing bacteria.

基于Arduino与Processing的心率检测计设计研究

随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的突发致命疾病之一,本文介绍的是一款基于Arduino【是基于易用硬件和软件的原型开源平台,包由可编程的电路板(简称微控制器),以及集成开发环境(称为Arduino IDE)的现成软件组成】Processing(开源编程语言,包括编辑器、编译器、展示器)的简易心率检测计系统,其功能实用、操作简单,可以测量心率,当超出正常心率范围时及时预警,是一款便携的实时心率测试仪。

Community analysis of ammonia-oxidizing bacteria in activated sludge of eight wastewater treatment systems

We investigated the communities of ammonia-oxidizing bacteria （AOB） in activated sludge collected from eight wastewater treatment systems using polymerase chain reaction （PCR） followed by terminal restriction fragment length polymorphism （T-RFLP）, cloning, and sequencing of the α-subunit of the ammonia monooxygenase gene （amoA）. The T-RFLP fingerprint analyses showed that different wastewater treatment systems harbored distinct AOB communities. However, there was no remarkable difference among the AOB T- RFLP profiles from different parts of the same system. The T-RFLP fingerprints showed that a full-scale wastewater treatment plant （WWTP） contained a larger number of dominant AOB species than a pilot-scale reactor. The source of influent affected the AOB community, and the WWTPs treating domestic wastewater contained a higher AOB diversity than those receiving mixed domestic and industrial wastewater. However, the AOB community structure was little affected by the treatment process in this study. Phylogenetic analysis of the cloned amoA genes clearly indicated that all the dominant AOB in the systems was closely related to Nitrosomonas spp. not to Nitrosospira spp. Members of the Nitrosomonas oligotropha and Nitrosomonas communis clusters were found in all samples, while members of Nitrosomonas europaea cluster occurred in some systems.

Impact of acetochlor on ammonia-oxidizing bacteria in microcosm soils

Acetochlor is an increasingly used herbicide on corn in North China. Currently, the effect of acetochlor on soil ammonia-oxidizing bacteria (AOB) communities is not well documented. Here, we studied the diversity and community composition of AOB in soil amended with three concentrations of acetochlor (50, 150, 250 mg/kg) and the control (0 mg acetochlor/kg soil) in a microcosm experiment by PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis) and the phylogenetic analysis of excised ...

Distribution of ammonia-oxidizing Betaproteobacteria community in surface sediment off the Changjiang River Estuary in summer

The spatial distribution of ammonia-oxidizing Betaproteobacteria （βAOB） was investigated by FISH （fluorescence in situ hybridization） and DGGE （denaturing gradient get electrophoresis） techniques in the sediment off the Changjiang River Estuary. Sediment samples were collected from eight stations in June before the formation of hypoxia zone in 2006. The abundance of βAOB ranged from 1.87× 10^5 to 3.53×10^5 cells/g of sediment. βAOB abundance did not present a negative correlation with salinity, whereas salinity was implicated as the primary factor affecting nitrification rates. The DGGE profiles of PCR-amplified amoA gene fragments revealed that the βAOB community structure of sample S2 separated from other samples at the level of 40% similarity. The variations in composition ofβAOB were significantly correlated with the salinity, temperature, absorption ability of sediments and TOC. The statistical analysis indicates that theβAOB abundance was a main factor to influence nitrification rates with an influence ratio of 87.7% at the level of 40% biodiversity similarity. Considering the good correlation between βAOB abundance and nitrification estimates, the abundance and diversity of βAOB community could be expected as an indirect index of nitrification activity at the study sea area in summer.

Seasonal and spatial distribution of ammonia-oxidizing microorganism communities in surface sediments from the East China Sea

Ammonia oxidation plays a significant role in the nitrogen cycle in marine sediments. Seasonal and spatial distribution of ammonia-oxidizing archaea （AOA） and betaproteobacteria （13-AOB） in surface sediments from the East China Sea （ECS） were investigated using ammonia monooxygenase ct subunit （amoA） gene. In order to characterize the community of AOA and 13-AOB, real-time quantitative polymerase chain reaction （qPCR） was carried out in this study, along with environmental parameters. The abundance of 13-AOB amoA gene （2.17x 10^6-4.54x10^7 copy numbers per gram wet weight sediment） was always greater than that ofAOA amoA gene （2.18x 105-9.89x 10^6 copy numbers per gram wet weight sediment） in all sampling stations. The qPCR results were correlated with environmental parameters. AOA amoA gene copy numbers in April were positively related to temperature and nitrite concentration （p〈0.05）. 13-AOB amoA gene copy numbers in August correlated negatively with salinity （p〈0.01）, and correlated positively with ammonium concentration （p〈0.05）. With the increase of salinity, the amoA gene copy ratio of AOB to AOA had a tendency to decrease, which suggested 13-AOB dominated in the area of high level ammonium and AOA preferred high salinity area.

Nitrification intensity and ammonia-oxidizing bacteria and archaea in different wetland plant rhizosphere soils

In order to explore the nitrogen removal process in constructed wetlands(CW s),the moisture,ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3"-N)and nitrification intensity in three wetland plant rhizosphere soils(Acorns calamus,Typha orientalis,Iris pseudacorus)were investigated at a relatively normal temperature range of15to25The relative abundance of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)were also achieved using fluorescence in situ hybridization(FISH).It is found that T.orientalis achieves the highest nitrification intensity of2.03m g(h?kg)while the second is I.pseudacorrs(1.74m g/(h?kg)),and followed by A.calamus(1.65m g/(h?kg))throughout the experiment.FISH reveals that the abundance of bacteria(1010g_1wet soil)is higher than that of archaea(109g_1wet soil),and AOBare the dominant bacteria in the ammonia oxidation process.The abundance of AOB in te rhizosphere soils from high to low T.orientalis(1.88x1010g"1),I pseudacorus(1.23x1010g1),A.calamus(5.07x109g"1)while the abundance of AOA from high to low ae I.pseudacorus(4.00x109g1),A.calamus(3.52x109g"1),T.orientalis(3.48x109g"1).The study provides valuable evidence of plant selection for nitrogen removal in CWs.

Response of ammonia-oxidizing betaproteobacteria to short- term fertilization in a salt marsh in China

This study examines the impacts of short-term(6 months) fertilization on the community structure and abundance of ammonia-oxidizing betaproteobacteria(β-AOB) and the potential nitrification rate in sediment colonized by S uaeda heteroptera in a saltmarsh located in Shuangtai estuary, China. The sediment samples were collected from plots treated with different amounts of an N fertilizer(urea supplied at 0.1, 0.2, 0.4, and 0.8 g/kg(nitrogen content in dry sediment)), and with different forms of N fertilizers(urea,(NH4) 2 SO 4, and NH_4NO_3, each supplied at 0.2 g/kg). The fertilizers were applied 1–4 times during the plant-growing season in May, July, August and September of 2013. Untreated plots were included as a control. As revealed in denaturing gradient gel electrophoresis of the 16 S r RNA gene, the β-AOB community responded to both the amount and form of N. Real-time quantitative PCR indicated that both abundance and potential nitrification rate of β-AOB increased after N addition, regardless of concentration and form(except NH_4NO_3). These results provide evidence that short-term N application influences the sediment β-AOB community, β-AOB abundance and potential nitrification rate in a saltmarsh ecosystem.

Compositional Shifts in Ammonia-Oxidizing Microorganism Communities of Eight Geographically Different Paddy Soils —Biogeographical Distribution of Ammonia-Oxidizing Microorganisms

Soil nitrification is mediated by ammonia-oxidizing archaea (AOA) and bacteria (AOB), which occupy different specialized ecological niches. However, little is known about the diversification of AOA and AOB communities in a large geographical scale. Here, eight paddy soils collected from different geographic regions in China were selected to investigate the spatial distribution of AOA and AOB, and their potential nitrification activity (PNA). The result showed that the abundance of AOA was predominant over AOB, indicating that the rice fields favor the growth of AOA. PNA highly varied from 0.43 to 3.57 μg NOX-N·g·dry·soil·h-1, and was positively related with soil NH3 content, the abundance of AOA community, and negatively related with the diversity of AOB community (P amoA genes revealed remarkable differences in the compositions of AOA and AOB community. Phylogenetic analyses of amoA genes showed that Nitrosospiracluster-3-like and Nitrosomonas cluster 7-like AOB extensively dominated the AOB communities, and 54d9-like AOA within the soil group 1.1b predominated in AOA communities in paddy soils. Redundancy analysis suggested that the spatial variations of AOA community structure were influenced by soil TN content (P < 0.01), while no significant correlation between AOB community structure and soil properties was found. Findings highlight that ammonia oxidizers exhibit spatial variations in complex paddy fields due to the joint influence of soil variables associated with N availability.

Characterization of Bacterial Community,Ammonia-Oxidizing Bacteria,and Nitrospira During the Operation of a Commercial-Scale Recirculating Aquaculture System for Culturing Pufferfish Takifugu rubripes

We investigated the changes in communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira during the operation of a pufferfish Takifugu rubripes recirculating aquaculture system by using high-throughput DNA sequencing.Differences in bacterial communities were observed at days 1-32,47-62 and 78-93 of biofilm development by using 16S rRNA gene pyrosequencing.The relative abundance of Proteobacteria(Gammaproteobacteria)increased,while that of Bacteroidetes(Flavobacteria)decreased.The proportions of Nitrosomonas and Nitrospina ranged from 0.02%to 0.30%and from 0.02%to 0.83%,respectively.Ammonia monooxygenase gene pyrosequencing revealed that the top three operational taxonomic units were related to Nitrosomonas aestuarii(17.5%-61.1%),uncultured beta proteobacterium clone B67S-54(1.9%-45.2%),and uncultured bacterium clone AZPa8(3.6%-24.7%).Nitrite oxidoreductase gene pyrosequencing revealed that the relative abundance of the dominant strain Nitrospira sp.Ecomares 2.1 increased,but that of the abundant species Nitrospira marina decreased.Our results demonstrated that the communities of bacteria,ammonia-oxidizing bacteria,and Nitrospira were changing during the operation of the pufferfish recirculating aquaculture system.

Distribution characteristics of ammonia-oxidizing bacteria in the Typha latifolia constructed wetlands using fluorescent in situ hybridization(FISH)

A molecular biology method, fluorescent in situ hybridization（FISH）, in which the pre-treatment was improved in allusion to the media of the constructed wetlands（CW）, e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria（AOB） quantity and the relation with oxidation-reduction potential（ORP） in the Typha latifolia constructed wetlands under three different Ioadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage.

Variation of Potential Nitrification and Ammonia-Oxidizing Bacterial Community with Plant-Growing Period in Apple Orchard Soil

In this study, we investigated the potential nitrification and community structure of soil-based ammonia-oxidizing bacteria （AOB） in apple orchard soil during different growth periods and explored the effects of environmental factors on nitrification activity and AOB community composition in the soil of a Hanfu apple orchard, using a culture-dependent technique and denaturing gradient gel electrophoresis （DGGE）. We observed that nitrification activity and AOB abundance were the highest in November, lower in May, and the lowest in July. The results of statistical analysis indicated that total nitrogen （N） content, NH4＋-N content, NO3-N content, and pH showed significant correlations with AOB abundance and nitrification activity in soil. The Shannon-Winner diversity, as well as species richness and evenness indices （determined by PCR-DGGE banding patterns） in soil samples were the highest in September, but the lowest in July, when compared to additional sampled dates. The DGGE fingerprints of soil-based 16S rRNA genes in November were apparently distinct from those observed in May, July, and September, possessing the lowest species richness indices and the highest dominance indices among all four growth periods. Fourteen DGGE bands were excised for sequencing. The resulting analysis indicated that all AOB communities belonged to the 13-Proteobacteria phylum, with the dominant AOB showing high similarity to the Nitrosospira genus. Therefore, soil-based environmental factors, such as pH variation and content of NHa＋-N and NO3--N, can substantially influence the abundance of AOB communities in soil, and play a critical role in soil-based nitrification kinetics.

Constraints on Characteristics and Distribution of Gas Hydrate and Free Gas Using Broad-Band Processing of Three-Dimensional Seismic Data

Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3D)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing sediments.Several geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas hydrate.The inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing layers.However,the gas hydrate saturation value at the adjacent canyon is 70%,with 30-m-thick patches and linear features.The lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing layer.Moreover,the BSR depths based on broad-band reprocessed 3D seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin.

Design and optimization of a greener sinomenine hydrochloride preparation process considering variations among different batches of the medicinal herb

The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 points.To solve these problems,a new process using anisole as the extractant was proposed.Anisole exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing steps.After alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried out.The process was modeled and optimized.The design space was constructed.The recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid concentration.The new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer rate.The sinomenine transfer rate was about 20%higher than that of industrial processes.The greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry.

Investigation on taste characteristics and sensory perception of soft-boiled chicken during oral processing based on electronic tongue and electronic nose

The sensory perception of food is a dynamic process,which is closely related to the release of flavor substances during oral processing.It’s not only affected by the food material,but also subjected to the individual oral environment.To explore the oral processing characteristics of soft-boiled chicken,the sensory properties,texture,particle size,viscosity,characteristic values of electronic nose and tongue of different chicken samples were investigated.The correlation analysis showed that the physical characteristics especially the cohesiveness,springiness,resilience of the sample determined oral processing behavior.The addition of chicken skin played a role in lubrication during oral processing.The particle size of the bolus was heightened at the early stage,and the fluidity was enhanced in the end,which reduced the chewing time to the swallowing point and raised the aromatic compounds signal of electronic nose.But the effect of chicken skin on chicken thigh with relatively high fat content,was opposite in electronic nose,which had a certain masking effect on the perception of umami and sweet taste.In conclusion,fat played a critical role in chicken oral processing and chicken thigh had obvious advantages in comprehensive evaluation of soft-boiled chicken,which was more popular among people.

Toluene Processed All-Polymer Solar Cells with 18%Efficiency and Enhanced Stability Enabled by Solid Additive:Comparison Between Sequential-Processing and Blend-Casting

The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials development,so that a majority of the PSMAs have not fulfilled their potentials.Furthermore,most high-performance all-PSCs rely on the use of chloroform as the processing solvent.For instance,the recent highperformance PSMA,named PJ1-γ,with high LUMO,and HOMO levels,could only achieve a PCE of 16.1%with a high-energy-level donor(JD40)using chloroform.Herein,we present a methodology combining sequential processing(SqP)with the addition of 0.5%wt PC_(71)BM as a solid additive(SA)to achieve an impressive efficiency of 18.0%for all-PSCs processed from toluene,an aromatic hydrocarbon solvent.Compared to the conventional blend-casting(BC)method whose best efficiency(16.7%)could only be achieved using chloroform,the SqP method significantly boosted the device efficiency using toluene as the processing solvent.In addition,the donor we employ is the classic PM6 that has deeper energy levels than JD40,which provides low energy loss for the device.We compare the results with another PSMA(PYF-T-o)with the same method.Finally,an improved photostability of the SqP devices with the incorporation of SA is demonstrated.

Effects of friction stir processing and nano-hydroxyapatite on the microstructure,hardness,degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications

Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinement of microstructure,as well as reinforcement particles can significantly improve the degradation rate.In this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were studied.The subsequent FSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three passes.This resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,respectively.It is found that increasing FSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation rate.The corrosion rate of the FSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n HA.Additionally,the growing Ca-P and Mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation rate.The wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base metal.Also,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n HA composite after three passes.These results raise that the grain refinement by FSP and introduction of n HA particles significantly improved the degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications.

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing

A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this work.The structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was investigated.Moreover,a quantitative relationship between the microstructure and tensile yield strength was established.The results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were broken.In IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute atoms.The severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO phase.After MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% respectively.Grain refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP sample.In particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in IZ.This result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate.