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Background: Extracellular electron transfers (EETs) are mainly involved in anaerobic respiration of quinone-respiring strains, which is applicable in many fields, such as microbiological fuel cell, bio-hydrogen production, anoxic denitrification, and bio-reduction of azo dyes. However, this kind of instinctive function of microbes was nonspecific and low efficient, which needed to be improved by addition of exogenous redox mediators (RMs). In this work, vanillin, syringaldehyde and p-hydroxybenzaldehyde, as the precursors of lignin, were functionally modified to RMs in effort to accelerate the bio-reduction azo dyes.Results: The results showed that the decolorization efficiency of MO motivated by modified vanillin were increased from 20% to 95% in less than 12 h. And the modified syringaldehyde was increased to 85% in 24h. According to GC-MS, the modified products of vanillin and syringaldehyde were mainly kinds of phenols, ketones and quinones. The RMs exhibited better electrochemical performances by CV measurement and the •OH radicals were found according to EPR. Under saline condition, the strain, in the presence of RMs, still exhibited a high and stable removal efficiency to MO.Conclusions: The novel RMs of biodegradation to azo dyes were prepared from lignin monomers. The RMs based on bio-materials are environment-friendly and have a remarkable effect in biodegradation of azo dyes. This work may provide a new route for the functional utilization of lignin-resource and a theoretical guidance for efficient biodegradation of azo dye wastewater.

The treatment of breast cancer mainly relies on chemotherapy drugs, which present significant side effects. The most typical example is the cardiotoxicity and bone marrow suppression associated with doxorubicin (DOX). Therefore, this drug is not the first choice in clinical treatment. We designed ATN-FFPFF-ATN, a new targeted antitumor drug carrier, polymerized from phenylalanine dipeptide (FF), ATN-161 peptide, and Pluronic® F-127. The peptide and Pluronic® F-127 are linked with acetal and are, therefore, acid-sensitive. As cancer can reduce pH through complex mechanisms and subsequently maintain acid ambience, our vehicle can smartly unravel at a peculiar position, through which the drug can specifically accumulate inside the tumor. ATN-161 is a protein ligand of integrin α5β1, which is highly expressed on the surface of some breast cancer cells. This targeting peptide sequence can play a role in the selective delivery of DOX to tumor cells. The DOX-carrying vector was able to significantly inhibit cell proliferation and promote cell apoptosis in MDA-MB-231 cells. Based on these results, ATN-FFPFF-ATN with pH response is a promising vehicle for DOX delivery.

Yield mapping for citrus fruit is a challenging task due to factors such as varying illumination conditions, clustering, and occlusions. Mapping the yield for immature citrus fruit presents an additional challenge that is the colours of fruit and leaves are almost identical. Commonly used machine vision techniques using colour cameras become less effective for immature citrus fruit detection. This study explores a novel active thermal imaging method to tackle the problem of colour similarity between immature citrus fruit and leaves. In this study, a thermal camera was combined with a water spray system that applied water mist to citrus trees. The water mist caused temperatures of both the fruit and leaf surfaces to change but at different rates. Multiple parameters of the spray system were experimented with the goal to induce as much temperature differences as possible between fruit and leaf surfaces. The combined system was tested in a citrus grove for fruit detections. Deep learning models were built based on the active thermal imaging system and tracking and fruit counting algorithms were created to count fruit in thermal videos. A mean average precision of 87.2% was achieved by the models and an accuracy of 96% was achieved when comparing the number of fruit counted by the algorithms with the true number of fruit counted manually in the field.

After the treatment of liquid radioactive waste, there is a certain amount of Cs in the waste resin, and these Cs-doped resins are prone to volatilize during the thermal treatment process and cause radionuclide leakage. The molten salt oxidation (MSO) can effectively prevent the volatilization of toxic metal, especially the volatilization of Cs. Under nitrogen and air conditions, it is found that the oxidation behavior between Cs-doped and clean cation exchange resins (CERs) is quite different. In the presence of oxygen and molten carbonate salt, Cs

A novel dual-phase PHSS consisting of lath martensite plus allotriomorphic δ ferrite (ALF) with nanoprecipitates was characterized by high-resolution field emission transmission electron microscopy for quenched, solid-solution-treated, and aged stainless steel. The effects of aging at various durations prior to H2O or liquid N2 quenching were investigated. Cu-rich nanoprecipitates evolve from body-centered cubic clusters to 9R Cu under quenching to 3R Cu and subsequently to face-centered cubic ε-Cu at various aging durations. Maximum hardness was observed after aging at 600 °C for 1 h. However, after this aging, both reversed austenite and Cu-rich nanoprecipitates coexisted in the martensite matrix. The segregation and diffusion of austenite-stabilizing elements promoted the nucleation of reversed austenite.

A new organic crystal, [BzTPP][PIC](1) ([BzTPP]+ = benzyl triphenylphosphinium, [PIC]- = picrate), has been grown by slow evaporation solution growth technique. Single crystal XRD reveals that it belongs to monoclinic system with P21/c. The two neighboring [BzTPP]+ cations from a dimer through C-H···π interaction while anions stack into a columnar structure through N⋯O, O⋯O and π···π interaction. The anions and cations form a column structure alternately in ···AC-AC-AC-AC··· sequence through C-H⋯O hydrogen bonds. The experimental vibrational bands (IR and Raman) have been discussed and assigned based on DFT calculations. The HOMO-LUMO energy gap explains the charge transfer interactions in the molecule. The thermal stability of the hybrid crystal was analyzed by TG-TDA-MS technique and revealed that the title crystal was stable up to 290 °C. The fluorescence spectra reveal three main emission peaks at 295, 388 and 543 nm upon excitation at 250 nm in solid state at room temperature. The energy of weak interactions in the molecule and nonlinear optical properties were studies using DFT calculations.

Heparin, a highly sulfated glycosaminoglycan, has been used as a clinical anticoagulant over 80 years. However, heparin-induced thrombocytopenia and thrombosis (HITT) is a serious side effect of heparin therapy, resulting in relatively high risk of amputation and even death. HITT is caused by forming of complexes between heparin and platelet factor 4 (PF4). Enoxaparin, one of the most commonly used low molecular weight heparin (LMWH), were developed in 1980's. The lower molecular weight of enoxaparin reduces the risk of HITT by binding to less PF4. To detect the binding capacity between enoxaparin and PF4 could be an effect way to control this risk before it goes to patients. In this work, a size exclusion chromatography (SEC) method was developed to analyze the patterns of complexes formed between PF4 and enoxaparin. The chromatographic condition was optimized to separate PF4, enoxaparin, ultra-large complexes and small complexes. The linearity and stability of this method were confirmed. The impacts of PF4/enoxaparin mixture ratios and incubation time on the forming complexes were investigated. Four enoxaparin samples were analyzed with this method to verify its practicability. It is a robust, accurate and practicable method, and provides an easy way to monitor the capacity of enoxaparin forming complexes with PF4, suggesting the HITT related quality of enoxaparin.

A new high performance two-element V2X antenna array is presented, which is interspersed between two LTE antennas and designed in shark-fin environment. By using the specific designed lines and the closely EM coupling features, the desired current distributions in the element are achieved. Its high performance, with 10dB impedance bandwidth of 5% (5.7-6.0GHz), port isolation of 23 dB under the gain of 5.8dBi in elevation plane and the variation less than 5dBi in azimuthal plane, are finally verified by simulations and measurements, showing the great potential applications in automobile wireless communications.

A simple method for modeling the circular array and calculating its radiation pattern from a unit antenna’s spherical near-field data is presented. This method utilizes near-field data to calculate the transformation coefficient of spherical wave expansion (SWE) and thus performs a near-field to far-field transformation to obtain the radiation field. Then, the circular-ring antenna array’s radiation field is obtained by using a modified array factor. Comparison between full-wave simulations and presented method demonstrates the accuracy and efficiency of our method.

The nanocomposites with highly synergistic effect show important potential application as nanozymes. Herein, the chain-like Au/carbon dots (CDs) (GCDs) nanocomposites were prepared by self-assembly method. The negatively charged Au nanoparticles (NPs) and positively charged CDs were connected by the electrostatic interaction. Then, the electron transfer between Au and CDs induces the strong catalytic effect of GCDs nanocomposites. The cross-linking reaction occurred between amino groups and carboxyl groups on the surface of CDs, which led to form the chain-like Au aggregation surrounded by carbon shells. By FDTD simulation, the aggregation of Au NPs may enhance the electromagnetic field so that the surface-enhanced Raman scattering (SERS) signal can be increased based on GCDs nanocomposites as substrate. Otherwise, the GCDs nanocomposites can also be used to catalyze the oxidation of colourless3,3',5,5'-tetramethylbenzidine (TMB) to blue oxTMB in the presence of H2O2, which displays the enhanced peroxidase-like activity compared with alone Au NPs or CDs. The obvious oxidation process of TMB molecules may be monitored by the change of SERS signal during the catalytic reaction. On this basis, GCDs nanocomposites can be further used for detection of glucose. The detection level of glucose is obtained as low as 5 × 10-7 M. Therefore, this provides a method to detect the glucose based on GCDs nanocomposites as an enzyme mimic.

An organic–inorganic hybrid crystal, [Bz-4-NH2Py]2[CdBr4](1) (Bz-4-NH2Py = 1-benzyl-4′-aminopyridinium), was grown successfully by slow evaporation solution growth method at room temperature and characterized. In tetrachlorocadmate(II) dianion, the CdII ion is coordinated by four Br atoms in a close to tetrahedral geometry. The crystal packing is stabilized by C H⋯Br hydrogen bonds between [Bz-4-NH2Py]+ cations and [CdBr4]2− anion forming a three-dimensional network. Powder XRD diffraction study confirms the crystalline nature of the title compound. Thermal stability and the gaseous products of decomposition at 362 °C were examined by TG-DTA-MS technique. The Fourier transform infrared (FT-IR) and Raman spectra were recorded and analyzed with the aid of DFT calculations in order to make a suitable assignment of the observed bands. UV–Vis spectral analysis was used to determine the band gap energy, and the nonlinear optical (NLO) effect of the compound was predicted using DFT. Further, the title compound exhibits strong fluorescence emission at 394, 329 and 467 nm in the solid at room temperature.

For early yield estimation and harvest management, the recognition of blueberry fruit and their maturity is essential since blueberries do not ripen at the same time. This study was conducted to recognise visible blueberry fruit with different maturity using outdoor colour images acquired from a commercial field. The maturity of blueberry was divided into three different growth stages: mature, intermediate and young. The following stepwise algorithm was developed to identify the blueberry fruit: (1) A fruit training set was constructed using 1374 patches cropped from the original colour images. (2) HOG (Histogram Oriented Gradients) feature vectors were calculated from these patches, and a linear SVM (Support Vector Machine) classifier was trained to detect fruit-like regions rapidly. (3) Using a* and b* features in the L*a*b* colour space to discard non-fruit regions as well as categorise three fruit groups on those fruit-like regions. The KNN (K-nearest Neighbour) and a newly developed TMWE (Template Matching with Weighted Euclidean Distance) classifiers were applied to identify the fruit of different maturity. The performance of the method was evaluated using average detection accuracy on the testing images, missed rate, and incorrect detection rate of false positives. KNN classifier yielded the best average accuracy of 86.0%, 94.2% and 96.0% for young fruit, intermediate fruit and mature fruit, respectively. The proposed TMWE classifier gave a relatively high accuracy at lower computation cost. The results indicated that the method of this study is efficient in recognising blueberry fruit with different maturity using colour images in outdoor scenes.

In precision agriculture, estimating crop yield using remote sensing techniques is an active research field. To achieve high accuracies, researchers frequently combined different imaging sources, such as colour (Red, Green, Blue [RGB]) images, thermal images, and near-infrared images. However, fusing information from those images has been a difficult task. Therefore, accurate image registration methods are necessary. This study aimed to develop a thermal-colour camera system which will register thermal images with colour images of tree canopies in preparation of information fusion and fruit detection. The registration method created in this study was based on photogrammetry. In preparation of registration, a camera system was built, consisting of a thermal camera and two colour cameras. Camera calibration, image intersection, and space resection were combined in a single step named ‘stereo-calibration’, to compute cameras' parameters and poses. Speeded-up robust features (SURF) were used to find points of interest from colour images. Random sample consensus (RANSAC) was utilised to search for optimal homography transforms between thermal and colour images. In addition, this study created a procedure for accurate registrations of regions of interest in thermal-colour image pairs, utilising structural similarity (SSIM) index. The proposed method offered pixel-level registration accuracy and achieved an average accuracy of 3 pixels in 640 × 480 – pixel citrus canopy images.

Citrus fruit detection is one of the most important and challenging steps in citrus yield mapping. The distinct color differences between the ripe fruit and leaves allowed previously-described imaging-based methods to achieve good results. However, immature green citrus fruit detection, which aims to provide valuable information for citrus yield mapping at earlier stages is much more difficult because the fruit and leaf colors are very similar. This study combines color and thermal images for immature green fruit detections. Experiments identified optimal conditions for thermal imaging. A multimodal imaging platform was built to integrate color and thermal cameras. A novel image registration method was developed for combining color and thermal images and matching fruit in both images which achieved pixel-level accuracy. A new Color-Thermal Combined Probability (CTCP) algorithm was created to effectively fuse information from the color and thermal images to classify potential image regions into fruit and non-fruit classes. Algorithms were also developed to integrate image registration, information fusion and fruit classification and detection into a single step for real-time processing. An increase in recall rate from 78.1% when using only color images to 90.4% after fusing the color and thermal images was obtained at similar precision rates, and an increase in precision rate from 86.6% to 95.5% was obtained at similar recall rates. The fusion of the color and thermal images effectively improved immature green citrus fruit detection.

Detecting immature fruit in groves provides a promising benefit for growers to plan application of nutrients and estimate their yield and profit prior to harvesting. The goal of this study was to develop a robust algorithm to detect and count immature citrus fruit in images of the tree canopy. Images were all taken in low natural light conditions with a flashlight, and the green component of the colour images was used for further analysis. Local intensity maxima were detected and local binary pattern (LBP) features around them were extracted as an input of an ensemble classifier-RUSBoost. The positive predictions were considered as candidates and the hierarchical contour maps around them were extracted and fitted with Circular Hough Transform. The fitted circles were predicted as fruit targets if its radius were in a predetermined range. The algorithm was evaluated with a test set of 25 images, achieved 80.4% true positive rate and 82.3% precision rate, and F-measure was 81.3%. The good performance of occlusion tolerance of the proposed method was mainly coming from the robust LBP texture descriptor and hierarchical contour analysis (HCA) which used the pattern of light intensity distribution on fruit surface. This study proposed an innovative method to detect green fruit in images of trees only by using texture and intensity distribution.

The original version of this article unfortunately contained a mistake. The affiliation “China West Normal University” should be removed from the author Dr. Chenglin Wang. The correct affiliation details are given below.

Autonomous agricultural robots will be important for future smart farms. Autonomous navigation as one of the robots’ abilities, could save labors for driving vehicles and provide accurate and consistent localizations to perform farm operations. The goal of this study was to develop a navigation system that could guide a field robot to travel from a farm station to a citrus grove and visit each tree autonomously with obstacle avoidance ability. The system was developed with consideration of the concept of future smart farms, in which internet of things and big data analysis would be implemented.

An ultrafine-grained Al-Zn-Mg-0.1Sc-0.1Zr alloy was obtained by warm equal channel angular pressing (ECAP) and cold rolling. The microstructure evolution of the alloy during deformation and after subsequent aging was investigated by transmission electron microscopy. The results showed that the alloy grains were remarkably refined and that the dislocation density considerably increased after serve deformation. Tensile tests revealed that the yield strength (YS), ultimate tensile strength (UTS) and elongation of the cold-rolled Al-Zn-Mg-Sc-Zr alloy were ~ 456 MPa, ~ 469 MPa and 16.7%, respectively. After 16 ECAP passes, higher strength (YS: ~ 526 MPa, UTS: ~ 589 MPa) was achieved, with the elongation decreasing to ~ 11.7%. After optimal aging, the YS and UTS of the sample subjected to 16 ECAP passes increased to ~ 594 MPa and ~ 606 MPa, respectively, maintaining an appropriate elongation of ~ 10%. The main strengthening mechanisms and microstructure evolution during ECAP and subsequent aging was discussed.

Mo-containing high-level nuclear waste borosilicate glasses were investigated as part of an effort to improve Mo loading while avoiding yellow phase crystallization. Previous work showed that additions of vanadium decrease yellow phase formation and increases Mo solubility. X-ray absorption spectroscopy (XAS) and Raman spectroscopy were used to characterize Mo environments in HLW borosilicate glasses and to investigate possible structural relationships between Mo and V. Mo XAS spectra for the glasses indicate isolated tetrahedral Mo6+O4 with Mo-O distances near 1.75 A. V XANES indicate tetrahedral V5+O4 as the dominant species. Raman spectra show composition dependent trends, where Mo-O symmetrical stretch mode frequencies (ν1) are sensitive to the mix of alkali and alkaline earth cations, decreasing by up to 10 cm−1 for glasses that change from Li+ to Na+ as the dominant network-modifying species. This indicates that MoO4 tetrahedra are isolated from the borosilicate network and are surrounded, at least partly, by Na+ and Li+. Secondary ν1 frequency effects, with changes up to 7 cm−1, were also observed with increasing V2O5 and MoO3 content. These secondary trends may indicate MoO4-MoO4 and MoO4-VO4 clustering, suggesting that V additions may stabilize Mo in the matrix with respect to yellow phase formation.

This paper introduces a typical corrosion phenomenon of the Integrated Circuits. A three-terminal adjustable shunt regulator outputted abnormal voltage on a PCBA because its Vref pin was open. Bonding pad corrosion was confirmed by SEM&EDX analysis. The pad was electrical open to the surrounding schematic. After a whole investigation, several lots of wafers were confirmed to be contaminated by silicone oil which was introduced during the demolding process. Delamination occurred between the molding compound and die. Plating solution which contained chlorine and sulphur percolated into package during Tin Plating.Supplier of the regulator was recommended to improve the demolding process. Besides, routine reliability monitoring(such as C-SAM, HAST) can be executed in quality control process to eliminate this failure mode in customer’s application.

Current approaches to topdressing and weeding operations for rice cultivation present several disadvantages, such as poor precision, low efficiency, serious environmental pollution, and so on. This paper presents a row-controlled fertilizing–weeding machine to improve the precision of fertilizing and weeding operations and to reduce the heavy pollution associated with rice cultivation. A proportional–integral–derivative algorithm was adopted to realize accurate fertilization control, and an automatic driving system for agricultural machinery based on BeiDou navigation was used for accurate row-controlled operation. Accuracy testing and field experiments were carried out. The results show that the fertilization control system can stabilize the speed to within 0.55 s of the desired speed with a standard deviation of around 0.32 r·min−1. The row-controlled operation ensures the lateral deviation is within ± 5 cm at operating speeds below 5 km·h−1. The high uniformity and accuracy of fertilization meet agronomic requirements and rice cultivation standards, and the weeding performance is acceptable at working speeds below 5 km·h−1.

Fondaparinux, a synthetic pentasaccharide anticoagulant based on heparin antithrombin-binding domain, is derived from a chemical synthesis with more than 50 steps. Herein, we identified nine analogues separated from commercially available crude fondaparinux sodium, and tested their anticoagulant activity in vitro. Based on the activity results, the most active derivative Rrt1.17 was chemically synthesized. Biological properties in vitro and in vivo indicated that the well-defined derivative Rrt1.17 was a more efficient anticoagulant candidate compared with fondaparinux.

Being superior to natural enzymes, nanoenzymes are drawing a great deal of attention in the field of biosensing. Herein, we developed an ultrasensitive, stable and selective colorimetric assay having dual functionalities of Au-tipped Pt nanorods (NRs). The optical and catalytic properties of Au-tipped Pt NRs were monitored using a spectrophotometer and the chromogenic substrate 3, 3&prime, 5, 5&prime, tetramethylbenzidine (TMB) in the presence of H2O2, respectively. We found that Au-tipped Pt NRs exhibited excellent peroxidase-like activity, which decomposed hydrogen peroxide (H2O2) into oxygen (O2). The produced O2 oxidized the chromogenic substrate into a blue color product. The oxidation rate of the chromogenic substrate could be monitored using a spectrophotometer at 652 nm. Notably, the peroxidase-like activity of Au-tipped Pt NRs decreased in the presence of ascorbic acid (AA). The produced O2 preferentially reacted with AA, generating ascorbyl radicals (AA&middot, ) instead of oxidizing TMB, and thereby decreased the oxidation rate of TMB. Based on this inhibitory property, a selective colorimetric assay was developed using Au-tipped Pt NRs for the detection of AA. This work offers a novel detection method for AA.

A computer-generated hologram (CGH) is the core component for an aspheric surface test. According to fabrication demands, it is necessary to convert the designed CGH phase compensation function into the processed pattern, that is, the fringe discretization process. In this paper, we propose a new discretization method for a CGH in a test of the freeform surface, and realized the encoding of processed fringes by MATLAB software. Furthermore, we designed the experiment to verify the accuracy of the new discretization method and compared the calculation efficiency between the new algorithm and the reported algorithm. Finally, based on the testing requirement of a freeform mirror in a camera optical system, we completed the design, encoding, and fabrication of the CGH sample, and analyzed the influence of various errors on wavefront accuracy of the CGH.

The stem sap flow rate of Haloxylon ammodendron plantation in the Minqin oasis-desert ectone was measured by the thermal dissipation probe (TDP). A cross-correlation analysis was used to estimate the time lag between the stem sap flow and the environmental factors influencing transpiration, including photosynthetically active radiation (PAR) and water vapor pressure deficit (VPD). The results showed that the stem sap flow rate of H. ammodendron had substantial seasonal variation, with the monthly average sap flow being the highest in June and the lowest in August. There was an obvious time lag between the stem sap flow of H. ammodendron and PAR and VPD. The stem sap flow was lagged behind PAR for 80 min but it was ahead of VPD for 114 min. Additionally, the time lag exhibited significant difference among different months during the growth season from May to September. The sap flow of H. ammodendron was more dependent on the variation of PAR on the daily scale than VPD, but it was more closely related to VPD during the day time. The time lag between the stem sap flow and PAR/VPD had no significant correlation with the tree factors (including plant height, ground diameter, diameter at 50 cm height, under branch height, canopy size) and the nocturnal sap flow.应用Granier热扩散探针测定民勤绿洲荒漠过渡带梭梭人工林的树干液流,将液流与饱和水汽压差(VPD)和光合有效辐射(PAR)数据分别进行逐行错位分析,探讨树干液流与环境因子之间的时滞效应.结果表明: 梭梭日液流速率呈现明显的季节变化,6月平均液流速率最大,8月平均液流速率最小.生长季(5—9月)梭梭树干液流与光合有效辐射、饱和水汽压差存在明显的时滞,树干液流滞后于PAR 80 min,提前于VPD 114 min,且不同月份的时滞长短存在差异.尽管梭梭树干液流在日尺度上更加依赖于PAR的变化,但在白天,树干液流与饱和水汽压差间有更紧密的关系.梭梭生长季树干液流与VPD或PAR之间的时滞与树形因子(株高、地径、50 cm处直径、枝下高、冠幅)及夜间液流量的相关性均不显著.

Low molecular weight heparins (LMWHs), derived from unfractionated heparin (UFH) by chemical or enzymatic degradation, have lower side effects than that of heparin. Enoxaparin, nadroparin, and dalteparin are the most widely used LMWHs. Nadroparin and dalteparin are prepared through nitrous acid degradation followed by a subsequent reduction process, in which specific residue, 2,5-anhydro- d -mannitol (An-Man), is formed at the reducing terminals of generated sugar chains. However, few practicable analytical method was available to analyze An-Man qualitatively and quantitatively. In this work, a HPAEC-PAD-MS method was developed to analyze monosaccharides in heparin and LMWHs, especially An-Man. An ion suppressor is set up between HPAEC and MS to remove the nonvolatile salts from HPAEC and make the elute compatible to MS. Various monosaccharides were separated well with HPAEC. Online MS and MS/MS confirmed all sugar residues in the hydrolysates of heparin samples. The specific residue, An-Man, was only observed in the hydrolysates of LMWHs prepared with nitrous acid degradation and reduction. In addition, major glucosamine and minor arabinose/galactose were observed in all heparin samples. The amounts of these sugar residues were quantitated with PAD, simultaneously. The ratio of glucosamine to An-Man could be used to calculate the molecular weight of LMWHs. The calculated values are comparable to the value measured with size-exclusion chromatography-multiple angle laser scattering detection. Higher the ratio of glucosamine to An-Man higher the molecular weight. The HPAEC-PAD-MS platform is an accurate, precise and efficient way to identify LMWHs by determination of An-Man. It is also an alternative method to detect the MWs of LMWHs having An-Man for quality control purposes.

In this paper, molecular dynamics (MD) model is explored to study single-crystal nickel micro-nanomachining mechanism. Accordingly, LAMMPS would implement the simulation of nanometric cutting process, and snapshots at different steps are obtained by VMD and OVITO. On this basis, a reasonable explanation is given to the forming mechanism of chip and surface machined in the machining process of single-crystal nickel. The result of work-piece temperature distribution shows that there is a temperature gradient around the machining zone, where chip part achieved the highest temperature. Moreover, a large number of dislocations are observed. Part of dislocation atoms move forward and generate the chips, taking a lot of heat. Another part of dislocation atoms combine with the work-piece surface atoms with elastic recovery, and form the machined surface.

D-Gluconhydroximo-1,5-lactam and its oxime-substituted derivatives were prepared and assessed for inhibition and pharmacological chaperone (PC) activities in Gaucher disease cell lines derived from N370S. The most active compound, O-(D-glucopyranosylidene) amino-Z-N-dodecylcarbamate (38), gave a nearly 2.0-fold increase in N370S β-GCase activity at 12.5 μM with no inhibition to other commercially available glucosidases. Docking studies of ligand–enzyme interactions have also been conducted to account for the results of enzyme activity increase. All these results demonstrate that compound 38 is a promising PC for the treatment of GD.

Inspired by the biosynthesis of heparan sulfate (HS), we present a direct epimerization approach to l-iduronic acid synthons (IdoA) from the corresponding C5 epimers, d-glucuronic acids (GlcA). With the best result, 95 % conversion was achieved. Weak intramolecular interactions dramatically affect the equilibrium constants of this thermodynamically governed process. Based on this approach, GlcA and IdoA donors required for the synthesis of fondaparinux were prepared in 14 steps, whereas over 20 steps were required previously.

Energycane is emerging as a candidate bioenergy crop, and it resembles sugarcane in stature and cultivation practices. Preliminary trials indicated that sugarcane billet harvesters have insufficient power to harvest energycane. This study quantified the power requirements of selected harvester components and field performance of harvesters for sugarcane and energycane. The elevator pour rate for energycane was lower (43.3 Mg h−1, wet weight) than for sugarcane (132.7 Mg h−1, wet weight). At the observed pour rates, power consumption of the basecutter, elevator, and the entire harvester was comparable for energycane and sugarcane. However, the power requirements of the chopper were 1.65 times higher for energycane than for sugarcane. Greater stem damage and higher stubble heights were observed for energycane compared to sugarcane. Overflowing of the elevator was observed for energycane because of lower bulk density of the biomass (billets and trash, 143.8 kg m−3) compared to sugarcane (predominantly billets, 349.4 kg m−3). The field capacity of the harvester for energycane (0.32 ha h−1) was lower than for sugarcane (0.61 ha h−1), and the harvesting cost for energycane (5.91 $ Mg−1) was considerably higher than for sugarcane (1.87 $ Mg−1). Design modifications to the existing sugarcane harvester models would be needed to adapt them to harvest energycane.

A 'look-ahead' stem-bending yield sensor was developed for napiergrass.Stem-bending sensor performed better than pressures of harvester hydraulic drives.Stem-bending yield sensor predicted yield with 85-90% accuracy.Stem-bending sensor showed potential to control harvester ground speed. Napiergrass, which resembles sugarcane in stature and cultivation practices, is emerging as a candidate bioenergy crop. However, limited studies investigating harvesting and yield sensing of napiergrass are available. This study investigated stem-bending force, and the hydraulic pressures of basecutter, chopper and elevator drives in a John Deere 3522 sugarcane billet harvester as indicators of napiergrass yield. The coefficients of determination (R2) between napiergrass yield and hydraulic pressures were 0.73, 0.88 and 0.81, respectively for the basecutter, chopper and elevator drives. The highest correlation (R2=0.92) was found between stem-bending force and napiergrass yield. The yield prediction errors were 4.9% and 8.6% for the calibration and validation plots with the stem-bending force yield sensor. Cross-validation, in which each harvested row was treated as a data point, showed that the average yield prediction errors were 10.9% and 11.8% for the calibration and validation data sets. Yield maps were also generated employing the stem-bending yield sensor. In addition, it was expected that the stem-bending yield sensor could be utilized to control harvester operation such as travel speed. Further studies would be needed to extend the stem-bending concept to other thick stemmed crops.

Yield mapping is the first step for site-specific crop management. Many yield mapping systems have been developed for grain crops. However, it remains a difficult task for tree crops. In this study an autonomous yield mapping system for citrus crops was developed. The system was designed to detect fruit and create yield maps at early stages so that farmers could manage the grove site specifically based on the maps. It consisted of two major sub-systems, an autonomous navigation system and an imaging system. Robot Operating System (ROS) was used for developing the autonomous navigation system on top of an unmanned ground vehicle. An inertial measurement unit (IMU), wheel encoders and a GPS were integrated using an extended Kalman filter to provide reliable navigation solutions. In the imaging system, a high-resolution visible camera was carried by the vehicle for image acquisition. All the video frames were associated with latitude and longitude coordinates automatically. Detection of fruit from the video frames utilized a VGG16 model, which was trained with Faster-RCNN. Fruit detection was evaluated and an accuracy of 77% was achieved. The Lucas-Kanade optical flow method was used for tracking each detected fruit and counting the total number of fruit. The complete system was tested in a citrus grove in Florida.

High-level waste (HLW) glasses containing bismuth, phosphorus, and chromium were investigated using Raman and X-ray absorption spectroscopy (XAS). The novel and practically important occurrence of foaming on cooling of these melts is associated with P and Cr from the HLW. In response, glasses were synthesized where Bi 2 O 3 and P 2 O 5 contents were varied independently. Relationships between P and Cr were found, where as P 2 O 5 -content increases, chromate Cr–O stretch Raman modes diminish intensity, while Cr XAS shows that Cr reduces, from 50% Cr 6+ + 50% Cr 3+ to nearly 20% Cr 6+ + 80% Cr 3+ , explaining the chromate mode behavior. In the most P 2 O 5 -rich glass, the chromate Cr–O distance increases by approximately 0.10 A, which may indicate bonding between CrO 4 and PO 4 tetrahedra, similar to that in chromo-phosphates. The presence of chromo-phosphate domains in HLW melts can be linked to oxygen generation as a source of the foaming.

Strawberry growers in Florida suffer from a lack of efficient and accurate yield forecasts for strawberries, which would allow them to allocate optimal labor and equipment, as well as other resources for harvesting, transportation, and marketing. Accurate estimation of the number of strawberry flowers and their distribution in a strawberry field is, therefore, imperative for predicting the coming strawberry yield. Usually, the number of flowers and their distribution are estimated manually, which is time-consuming, labor-intensive, and subjective. In this paper, we develop an automatic strawberry flower detection system for yield prediction with minimal labor and time costs. The system used a small unmanned aerial vehicle (UAV) (DJI Technology Co., Ltd., Shenzhen, China) equipped with an RGB (red, green, blue) camera to capture near-ground images of two varieties (Sensation and Radiance) at two different heights (2 m and 3 m) and built orthoimages of a 402 m2 strawberry field. The orthoimages were automatically processed using the Pix4D software and split into sequential pieces for deep learning detection. A faster region-based convolutional neural network (R-CNN), a state-of-the-art deep neural network model, was chosen for the detection and counting of the number of flowers, mature strawberries, and immature strawberries. The mean average precision (mAP) was 0.83 for all detected objects at 2 m heights and 0.72 for all detected objects at 3 m heights. We adopted this model to count strawberry flowers in November and December from 2 m aerial images and compared the results with a manual count. The average deep learning counting accuracy was 84.1% with average occlusion of 13.5%. Using this system could provide accurate counts of strawberry flowers, which can be used to forecast future yields and build distribution maps to help farmers observe the growth cycle of strawberry fields.

With the development of modern agricultural science and technology, the phytotron, as a controlled environment laboratory, is applied widely in crop cultivation, breeding and other fields. Data acquisition and automatic control with high precision of microclimate parameters in phytotron becomes more and more important. In order to overcome the defects of conventional phytotron with complex layout and inconvenient maintenance, a new implementation scheme of monitoring system based on wireless sensor network for phytotron is presented in this paper. Different kinds of environmental parameters were collected by wireless node and sent to the monitoring center through wireless communication network, and then processed and controlled by the main controller collaborating with interactive interface equipment. Testing result shows that the monitoring system with friendly interface has advantages of high sensitivity, easy operation and flexible extension.