Lignin engineering in forest trees: From gene discovery to field trials

Wood is an abundant and renewable feedstock for the production of pulp,fuels,and biobased materials.However,wood is recalcitrant toward deconstruction into cellulose and simple sugars,mainly because of the presence of lignin,an aromatic polymer that shields cell-wall polysaccharides.Hence,numerous research efforts have focused on engineering lignin amount and composition to improve wood processability.Here,we focus on results that have been obtained by engineering the lignin biosynthesis and branching pathways in forest trees to reduce cell-wall recalcitrance,including the introduction of exotic lignin monomers.In addition,we draw general conclusions from over 20 years of field trial research with trees engineered to produce less or altered lignin.We discuss possible causes and solutions for the yield penalty that is often associated with lignin engineering in trees.Finally,we discuss how conventional and new breeding strategies can be combined to develop elite clones with desired lignin properties.We conclude this review with priorities for the development of commercially relevant lignin-engineered trees.

Field Transmission of 100G and Beyond:Multiple Baud Rates and Mixed Line Rates Using Nyquist-WDM Technology

In this paper, we describe successful joint experiments with Deutsche Telecom on long-haul transmission of 100G and beyond over standard single mode fiber （SSMF） and with in-line EDFA-only amplification. The transmission link consists of 8 nodes and 950 km installed SSMF in DT＇ s optical infrastructure. Laboratory SSMF was added for extended optical reach. The first field experiment involved transmission of 8 x 216.8 Gbit/s Nyquist-WDM signals over 1750 km with 21.6 dB average loss per span. Each channel, modulated by a 54.2 Gbaud PDM-CSRZ-QPSK signal, is on a 50 GHz grid, which produces a net spectral efficiency （SE） of 4 bit/s/Hz. We also describe mixed-data-rate transmission coexisting with 1T, 400G, and 100G channels. The 400G channel uses four independent subcarriers modulated by 28 Gbaud PDM-QPSK signals. This yields a net SE of 4 bit/s/Hz, and 13 optically generated subcarriers from a single optical source are used in the 1T channel with 25 Gbaud PDM-QPSK modulation. The 100G signal uses real-time coherent PDM-QPSK transponder with 15% overhead of soft-decision forward-error correction （SD-FEC）. The digital post filter and 1 -bit maximum-likelihood sequence estimation （MLSE） are introduced at the receiver DSP to suppress noise, linear crosstalk, and filtering effects. Our results show that future 400G and 1T channels that use Nyquist WDM can transmit over long-haul distances with higher SE and using the same QPSK format.

The Field Efficacy Trial of Several Fungicides for Controlling Rice Sheath Blight Disease (Rhizoctonia solani)

[Objective]The paper was to study the field fficacy of several fumgicide against rice sheath bligh(Rhicoetonia solm).[Method]Field efficacy trial was performed with three novel fungicides,75%tebuconazole.azxytrobin WG,75%tifloxystrobion-tebuconazole WG and 24%6 thi-fluzamide sC,while 30%difenoconazole-propiconazole EC and 10%jingangmyein AS,which had been Long circulated in production,were uwsed as contrl agents.[Result]The three novel fungicides had better control ffe on sheath blight than the control agents;75%tebuconazole.azoxys-trobin WG at the dase of 20 g/667 m2 received the best contrl efect,and the control efect was still 87.72%at 20 d post administration,and the yield increase efect was remarkable.The control efects of 75%tiloxystrobin-tebuconazole wG and 24%thifluzamide SC were 85.67%and 87.36%,repectively.[Conclusion]75%tebuconazole.azxoxystrobin wG,75%tifloxystrobin tebuconazole WC and 24%thiluamide SC could be promted as rotation fungicides to control rice sheath blight.

Effect of non-aflatoxigenic strains of Aspergillus flavus on aflatoxin contamination of pre-harvest peanuts in fields in China

Aflatoxin contamination of peanuts is one of the most concerns in peanut production in China.Applying nonaflatoxigenic Aspergillus flavus strains,based on competitive exclusion,has been proved to be a promising strategy to reduce aflatoxin contamination in pre-harvest peanuts.Two non-aflatoxigenic A.flavus strains collected in China,which have been proved effectively reducing aflatoxin in the laboratory,were mixed with high aflatoxin producer to the soil in peanut growing season.The two non-aflatoxigenic strains significantly(P<0.05)reduced aflatoxin contamination in peanut kernels under both normal and drought stresses in two fields.Compared to control,the total aflatoxin(sum of aflatoxin B1 and B2)was reduced 26.7–99.12%in field 1,and 84.96–99.33%in field 2.The aflatoxin was reduced 84.96–99.33%under drought stress in two fields.The present study indicated the non-aflatoxigenic A.flavus strains could be potential biocontrol agents for reducing aflatoxin contamination under field condition.

Impact of Commercial Organic Ameliorants on Nitrogen and Phosphorus Concentrations of Maize Biomass at Ninth Leaf and Silking Growth Stages

The response of grain yield, biomass yield and harvest index of maize to the application of commercial organic ameliorants was inconsistent and poor. Hence it was hypothesized that the supply of N and P to maize plants was inadequate during vegetative growth, resulting in low concentrations of the two nutrients in maize biomass. The effects of nine ameliorants on the N and P concentrations of maize plants at ninth leaf (V9) and silking (R1) stages of maize were studied over three years at Bothaville (8% clay), Ottosdal (12% clay) and Potchefstroom (34% clay). All ameliorants were applied as prescribed by manufacturers. The N and P concentrations in maize biomass of the ameliorants at V9 and R1 were lower, comparable or higher, showing that the inconsistent and poor response of yield parameters can not be ascribed to inadequate uptake of N and P. A matter of concern that justifies thorough investigation, is the prescribed use of Crop care and Growmor with partial and of Montys and Promis with no NPK fertilization, an unsustainable practice over the long term. Characterization of the active ingredient(s) of the ameliorants is deemed also of importance for better insight.

A Revisit to the Swedish Wet Compaction Method—A Case Study of the Burvattnet Dam Reconstruction

The Swedish Wet compaction method allows soil compaction at higher water content than conventional Dry compaction methods and can be used to advantage when difficulties arise in keeping to a certain Dry compaction water content. Wet compaction was frequently applied for dam core soils of glacial till (moraine) up until late 1970s, and despite several advantages it is since no longer used in engineering practice. During the reconstruction of Burvattnet Main Dam in Sweden, the lack of dry core soil together with severe weather conditions made Dry compaction almost impossible. On the basis of laboratory compaction tests performed in compliance with the standard from the 1950s, and field compaction trials on site, this paper describes the steps taken to revisit the Wet compaction method, which made it possible to continue the filling works in keeping with the timeline of the project.

Stability Analysis of Hybrid-Driven Underwater Glider

Hybrid-driven underwater glider is a new type of tmmanned underwater vehicle, which combines the advantages of autonomous underwater vehicles and traditional underwater gliders. The autonomous underwater vehicles have good maneuverability and can travel with a high speed, while the traditional underwater gliders are highlighted by low power consumption, long voyage, long endurance and good stealth characteristics. The hybrid-driven underwater gliders can realize variable motion profiles by their own buoyancy-driven and propeller propulsion systems. Stability of the mechanical system determines the performance of the system. In this paper, the Petrel-II hybrid-driven underwater glider developed by Tianjin University is selected as the research object and the stability of hybrid-driven underwater glider unitedly controlled by buoyancy and propeller has been targeted and evidenced. The dimensionless equations of the hybrid-driven underwater glider are obtained when the propeller is working. Then, the steady speed and steady glide path angle under steady-state motion have also been achieved. The steady-state operating conditions can be calculated when the hybrid-driven underwater glider reaches the desired steady-state motion. And the steady- state operating conditions are relatively conservative at the lower bound of the velocity range compared with the range of the velocity derived from the method of the composite Lyapunov function. By calculating the hydrodynamic coefficients of the Petrel-II hybrid-driven underwater glider, the simulation analysis has been conducted. In addition, the results of the field trials conducted in the South China Sea and the Danjiangkou Reservoir of China have been presented to illustrate the validity of the analysis and simulations.and to show the feasibility of the method of the composite Lyapunov function which verifies the stability of the Petrel-II hybrid-driven underwater glider.

Removal of metals by sorghum plants from contaminated land

The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carded out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum （Sorghum biocolor L.）, a high biomass energy plant. Ethylene diamine tetraacetate （EDTA）, ammonium nitrate （NH4NO3） and ammonium sulphate （（NH4）2SO4） were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils.

Seeding Performance Simulations and Experiments for a Spoon- Wheel Type Precision Cottonseed-Metering Device Based on EDEM

To study the effects of seed metering on seeding performance under different motion parameters,a simulation model for a spoonwheel type seeder was established.A seed meter was tested by using EDEM(Engineering Discrete Element Method)software to simulate its working process at different speeds and tilt angles.The trajectories of individual cottonseeds in the seed-metering device were obtained,concurrently,the stress trend in the grain group was determined as a function of time.The simulation results suggest that at larger speeds,the metering index of the seed meter gradually decreases,while the index and the missing index gradually increase.As the tilt angle increased,the multiples index and missing index gradually decreased,while the multiples index gradually increased.When the seed meter speed reached 50 r/min and the tilt angle was 15°,the seed meter had a relatively good working performance with a seed spacing acceptance index of 92.59%,a multiples index of 1.85%,and a missing rate index of 5.56%.The seed meter was tested on a bench by using a JPS-12 performance-tester bench.At the aforementioned speed and angle,the coefficient of variation for the cottonseed spacing was 2.1%.The field trial results indicated that the multiples and the missing rates were higher than those for the tester bench but still met a passing rate of more than 90%.The coefficient of variation for the seed spacing was less than 10%,suggesting that the design could be used for field sowing.The resulting seeding uniformity was higher under these conditions,which indicates that the seed meter has a better working performance and the bench has a good seeding effect.

Detection of biosignatures in Terrestrial analogs of Martian regions:Strategical and technical assessments

For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant planning and scientific implementation. Clearly, in order to detect potential life signals beyond Earth, fundamental questions, such as how to define such terms as “life” and “biosignature”, have been given considerable attention. Due to the high costs of direct exploration of Mars, Mars-like regions on Earth have been invaluable targets for astrobiological research, places where scientists could practice the search for “biosignatures” and refine ways to detect them. This review summarizes scientific instrumental techniques that have resulted from this work. Instruments must necessarily be our “eyes” and “hands” as we attempt to identify and quantify biosignatures on Mars.Scientific devices that can be applied in astrobiology include mass spectrometers and electromagnetic-spectrum-based spectrometers,redox potential indicators, circular dichroism polarimeters, in situ nucleic acid sequencers, life isolation/cultivation systems, and imagers.These devices and how to interpret the data they collect have been tested in Mars-analog extreme environments on Earth to validate their practicality on Mars. To anticipate the challenges of instrumental detection of biosignatures through the full evolutionary history of Mars, Terrestrial Mars analogs are divided into four major categories according to their similarities to different Martian geological periods(the Early-Middle Noachian Period, the Late Noachian-Early Hesperian Period, the Late Hesperian-Early Amazonian Period, and the Middle-Late Amazonian Period). Future missions are suggested that would focus more intensively on Mars’ Southern Hemisphere, once landing issues there are solved by advances in spacecraft engineering, since exploration of these early terrains will permit investigations covering a wider continuum of the shifting habitability of Mars through its geological history. Finally, this paper reviews practical applications of the range of scientific instruments listed above, based on the four categories of Mars analogs here on Earth. We review the selection of instruments suitable for autonomous robotic rover tests in these Mars analogs. From considerations of engineering efficiency,a Mars rover ought to be equipped with as few instrument assemblies as possible. Therefore, once candidate landing regions on Mars are defined, portable suites of instruments should be smartly devised on the basis of the known geological, geochemical, geomorphological,and chronological characteristics of each Martian landing region. Of course, if Mars sample-return missions are successful, such samples will allow experiments in laboratories on Earth that can be far more comprehensive and affordable than is likely to be practicable on Mars.To exclude false positive and false negative conclusions in the search for extraterrestrial life, multiple diverse and complementary analytical techniques must be combined, replicated, and carefully interpreted. The question of whether signatures of life can be detected on Mars is of the greatest importance. Answering that question is extremely challenging but appears to have become manageable.

NATIONAL FIELD TRIAL OF THE CHINESE CLASSIFICATION AND DIAGNOSTIC CRITERIA OF MENTAL DISORDERS: COMPREHENSIBILITY, ACCEPTABILITY AND APPLICABILITY

The Chinese Neurology and Psychiatry Association conducted a national field trial of its Chinese Classification and Diagnostic Criteria of Mental Disorders (CCMD-2) involov-ing 26 provinces and municipalities, 80 psychiatric institutes, and 224 professionals. The results were as follows: (1)95.2% of researchers considered the comprehensibility of the CCMD-2 diagnstic criteria good. Within the ten major categories, comprehensibility ranged from 85.7% to 100%. (2) Of those surveyed concerning the acceptibility of the CCCMD-2 diagnostic criteria, 85.9% considered them acceptable. In individual classifications, the rate ranged from 74.1% to 95.2%. (3) 1498 cases were tested. The overall applicability rate which indicated the consistency between the CCMD-2 result and the actual clinical diagnoses was found to be 87.6%, (averaging Kappa = 0.82,P<0.01), better than those obtained from non-Chinese systems of diagnosis.

Field Trial of 40 Gbit/s ETDM Prototype System over 219 km of Installed Single Mode Fiber

Transmission of 40Gbit/s NRZ signal was successfully demonstrated over 219km of installed SMF in KT's Daejeon area network. After transmission, the measured power penalty was 0.5dB for all the tributary channels.

Geo-Coordinated Parallel Coordinates (GCPC): Field trial studies of environmental data analysis

The large number of environmental problems faced by society in recent years has driven researchers to collect and study massive amounts of data in order to understand the complex relations that exist between people and the environment in which we live.Such datasets are often high dimensional and heterogeneous in nature,with complex geospatial relations.Analysing such data can be challenging,especially when there is a need to maintain spatial awareness as the non-spatial attributes are studied.Geo-Coordinated Parallel Coordinates(GCPC)is a geovisual analytics approach designed to support exploration and analysis within complex geospatial environmental data.Parallel coordinates are tightly coupled with a geospatial representation and an investigative scatterplot,all of which can be used to show,reorganize,filter,and highlight the high dimensional,heterogeneous,and geospatial aspects of the data.Two sets of field trials were conducted with expert data analysts to validate the real-world benefits of the approach for studying environmental data.The results of these evaluations were positive,providing real-world evidence and new insights regarding the value of using GCPC to explore among environmental datasets when there is a need to remain aware of the geospatial aspects of the data as the non-spatial elements are studied.

Narrowing Down the Targets： Towards Successful Genetic Engineering of Drought-Tolerant Crops

Drought is the most important environmental stress affecting agriculture worldwide. Exploiting yield potential and maintaining yield stability of crops in water-limited environments are urgent tasks that must be undertaken in order to guarantee food supply for the increasing world population. Tremendous efforts have been devoted to identifying key regulators in plant drought response through genetic, molecular, and biochemical studies using, in most cases, the model species Arabidopsis thaliana. However, only a small portion of these regulators have been explored as potential candidate genes for their application in the improvement of drought tolerance in crops. Based on biological functions, these genes can be classified into the following three categories： （1） stress-responsive transcriptional regulation （e.g. DREB1, AREB, NF-YB）; （2） post-transcriptional RNA or protein modifications such as phosphorylation/dephosphorylation （e.g. SnRK2, ABI1） and farnesylation （e.g. ERA1）; and （3） osomoprotectant metabolism or molecular chaperones （e.g. CspB）. While continuing down the path to discovery of new target genes, serious efforts are also focused on fine-tuning the expression of the known candidate genes for stress tolerance in specific temporal and spatial patterns to avoid negative effects in plant growth and development. These efforts are starting to bear fruit by showing yield improvements in several crops under a variety of water-deprivation conditions. As most such evaluations have been performed under controlled growth environments, a gap still remains between early success in the laboratory and the application of these techniques to the elite cultivars of staple crops in the field. Nevertheless, significant progress has been made in the identification of signaling pathways and master regulators for drought tolerance. The knowledge acquired will facilitate the genetic engineering of single or multiple targets and quantitative trait loci in key crops to create commercialrade cultivars with high-yielding potential under both optimal and suboptimal conditions.

A metallic anti-biofouling surface with a hierarchical topography containing nanostructures on curved micro-riblets

Metallic surface finishes have been used in the anti-biofouling,but it is very difficult to produce surfaces with hierarchically ordered structures.In the present study,anti-biofouling metallic surfaces with nanostructures superimposed on curved micro-riblets were produced via top-down fabrication.According to the attachment theory,these surfaces feature few attachment points for organisms,the nanostructures prevent the attachment of bacteria and algal zoospores,while the micro-riblets prohibit the settlement of macrofoulers.Anodic oxidation was performed to induce superhydrophilicity.It forms a hydration layer on the surface,which physically blocks foulant adsorption along with the anti-biofouling topography.We characterized the surfaces via scanning electron and atomic force microscopy,contact-angle measurement,and wear-resistance testing.The contact angle of the hierarchical structures was less than 1°.Laboratory settlement assays verified that bacterial attachment was dramatically reduced by the nanostructures and/or the hydration layer,attributable to superhydrophilicity.The micro-riblets prohibited the settlement of macrofoulers.Over 77 days of static immersion in the sea during summer,the metallic surface showed significantly less biofouling compared to a surface painted with an anticorrosive coating.

Shoot-Specific Down-Regulation of Protein Farnesyltransferase （α-Subunit） for Yield Protection against Drought in Canola

Canola （Brassica napus L.） is one of the most important oilseed crops in the world and its seed yield and quality are significantly affected by drought stress. As an innate and adaptive response to water deficit, land plants avoid potential damage by rapid biosynthesis of the phytohormone abscisic acid （ABA）, which triggers stomatal closure to reduce transpirational water loss. The ABA-mediated stomatal response is a dosage-dependent process; thus, one genetic engineering approach for achieving drought avoidance could be to sensitize the guard cell＇s responsiveness to this hormone. Recent genetic studies have pinpointed protein farnesyltransferase as a key negative regulator controlling ABA sensitivity in the guard cells. We have previously shown that down-regulation of the gene encoding Arabidopsis β-subunit of farnesyltransferase （ERA1） enhances the plant＇s sensitivity to ABA and drought tolerance. Although the β-subunit of famesyltransferase （AtFTA） is also implicated in ABA sensing, the effectiveness of using such a gene target for improving drought tolerance in a crop plant has not been validated. Here, we report the identification and characterization of the promoter of Arabidopsis hydroxypyruvate reductase （AtHPR1）, which expresses specifically in the shoot and not in non-photosynthetic tissues such as root. The promoter region of AtHPR1 contains the core motif of the well characterized dehydration-responsive cis-acting element and we have confirmed thatAtHPR1 expression is inducible by drought stress. Conditional and specific down-regulation of FTA in canola using the AtHPR1 promoter driving an RNAi construct resulted in yield protection against drought stress in the field. Using this molecular strategy, we have made significant progress in engineering drought tolerance in this important crop species.

Nitrification inhibitor nitrapyrin does not affect yield-scaled nitrous oxide emissions in a tropical grassland

Urea is the most common nitrogen(N)fertilizer used in the tropics but it has the risk of high gaseous nitrogen(N)losses.Use of nitrification inhibitor has been suggested as a potential mitigation measure for gaseous N losses in N fertilizer-applied fields.In a field trial on a tropical Andosol pastureland in Costa Rica,gaseous emissions of ammonia(NH_(3))and nitrous oxide(N_(2)O)and grass yield were quantified from plots treated with urea(U;41.7 kg N ha^(-1)application^(-1))and urea plus the nitrification inhibitor nitrapyrin(U+NI;41.7 kg N ha^(-1)application^(-1)and 350 g of nitrapyrin for each 100 kg of N applied)and control plots(without U and NI)over a six-month period(rainy season).Volatilization of NH_(3)(August to November)in U(7.4%±1.3%of N applied)and U+NI(8.1%±0.9%of N applied)were not significantly different(P>0.05).Emissions of N_(2)O in U and U+NI from June to November were significantly different(P<0.05)only in October,when N_(2)O emission in U+NI was higher than that in U.Yield and crude protein production of grass were significantly higher(P<0.05)in U and U+NI than in the control plots,but they were not significantly different between U and U+NI.There was no significant difference in yield-scaled N_(2)O emission between U(0.31±0.10 g N kg^(-1)dry matter)and U+NI(0.47±0.10 g N kg^(-1)dry matter).The results suggest that nitrapyrin is not a viable mitigation option for gaseous N losses under typical N fertilizer application practices of pasturelands at the study site.

Volatile organic compound emission and biochemical properties of degraded Ultisols ameliorated by no tillage and liming

TTie Ultisols in the Rana de Canamero area in Southwest Spain showed aluminum(Al)phytotoxicity,and the clearance of natural vegetation and decades of intensive conventional agriculture caused the deplation of soil organic matter(SOM).Therefore,we studied the long-term effects of no tillage and liming using sugar beet foam(SF)and red gypsum(RG),alone or in combination,on the restoration of Ultisols affected by acidification,Al phytotoxicity,and SOM depletion.We measured the main soil chemical properties,soil microbial biomass,soil enzyme activities involved in carbon,nitrogen,phosphorus,and sulfur mineralization,and the emission of volatile organic compounds(VOCs).The results indicated that liming effectively neutralized the soil acidity in the long term and,in combination with no tillage,significantly increased soil microbial biomass and enzyme activities.Twenty-three VOCs were detected using the proton transfer reaction-time of flight(PTR-ToF)technique,and both liming and tillage changed the VOC emission patterns.The greatest difference in VOC emission pattern was observed between no-tilled un-amended soils and tilled lime-amended soils,suggesting the activation of different metabolic pathways within the microbial communities of soils under different management.Differences in VOC emission patterns could be attributed to the decomposition of carbohydrates,which were also sustained by the higher enzyme activities in the lime-amended soils.