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In order to discover new leading compounds with high antifungal and antibacterial activities, in this study, fifteen novel pyrimidine derivatives with glycoside scaffolds were synthesized using d-glucose as a starting material by five-step reactions. All of the newly synthesized compounds were screened for their in vitro antifungal activities against Phytophthora infestans, Gibberella zeae, Botryosphaeria dothidea, Phompsis sp., Thanatephorus cucumeris, and antibacterial activities against Xanthomonas oryzae pv. oryzae and Xanthomonas citri subsp. citri. Bioassay results indicated that compounds 4l, 4m, and 4o showed better in vitro antifungal activity against P. infestans, with the EC50 values of 3.42, 3.99, and 2.73 μg/mL, respectively, than that of dimethomorph (4.49 μg/mL).

Large curvature aspheric optical elements are widely used in visual system. But its morphological detection is very difficult because its accuracy requirement is very high. When we use the self-developed multi-beam angle sensor (MBAS) to detect large curvature aspheric optical elements, the accuracy will be reduced due to spot distortion. Therefore, we propose a scheme combining distorted spot correction neural network (DSCNet) and gaussian fitting method to improve the detection accuracy of distorted spot center. We develop a spot discrimination method to determine spot region in multi-spot images. The spot discrimination threshold is obtained by the quantitative distribution of pixels in the connected domain. We design a DSCNet, which corrects the distorted spot to Gaussian spot, to extract the central information of distorted spot images by multiple pooling. The experimental results demonstrate that the DSCNet can effectively correct the distorted spot, and the spot center can be extracted to sub-pixel level, which improves the measurement accuracy of the MBAS. The standard deviations of plano-convex lenses with curvature radii of 500 mm, 700 mm and 1000 mm measured with the proposed method are respectively 0.0112 um, 0.0086 um and 0.0074 um.

In this study, 14 novel S-β-D-glucopyranosides of 1,2,4-triazole derivatives were synthesized and characterized by 1H NMR, 13C NMR, and HRMS. Then their antifungal activities against Gibberella zeae (G. zeae), Botryosphaeria dothidea (B. dothidea), Phompsis sp., Phytophthora infestans (P. infestans), Thanatephorus cucumeris (T. cucumeris) and antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas citri subsp. citri (Xcc) were evaluated. Bioassay results indicated that most of the title compounds exhibited good antifungal activities. Among them, compounds 4g, 4k, 4m, and 4n showed better antifungal activities against P. infestans with EC50 values of 4.98, 4.09, 3.85, and 4.90 μg/mL, respectively compared with Dimethomorph (6.06 μg/mL).

To solve limited efficiency and reliability issues caused by current manual quality control processes in optical lens (OL) production environments, we propose an automatic micro vision-based inspection system named MVIS used to capture the surface defect images and make the OL dataset and predictive inference. Because of low resolution and recognition, OL defects are weak, due to their ambiguous morphology and micro size, making a poor detection effect for the existing method. A deep-learning algorithm for a weak micro-defect detector named ISE-YOLO is proposed, making the best for deep layers, utilizing the ISE attention mechanism module in the neck, and introducing a novel class loss function to extract richer semantics from convolution layers and learning more information. Experimental results on the OL dataset show that ISE-YOLO demonstrates a better performance, with the mean average precision, recall, and F1 score increasing by 3.62%, 6.12% and 3.07% respectively, compared to the YOLOv5. In addition, compared with YOLOv7, which is the latest version of YOLO serials, the mean average precision of ISE-YOLO is improved by 2.58%, the weight size is decreased by more than 30% and the speed is increased by 16%.

To investigate the application of the multi-beam angle sensor (MBAS) to high-precision optical aspheric and freeform surfaces, which are critical components in optical systems, we present a method of using an MBAS to reconstruct an aspheric surface from angle data. The MBAS is based on a multi-autocollimator system with a microlens array, which can split the beam into several spots and can convert centroid detection of the light intensity into an angle measurement. The MBAS is designed to address the curvature-range problem via a circumferential scan better than other methods and automatically eliminates the tilt error caused by rotation of a workpiece. Using a tracking technique, the MBAS can automatically determine focal spot positions from the centroid measurement of the light intensity. This is directly related to the accuracy of the angular difference measurement. The experimental results confirm the feasibility of using an MBAS for 3D surface profile measurements of cylindrical surfaces.

A method for absolute distance measurement is developed here that uses a Fizeau-type spectroscopic interferometer with a Fabry−Perot etalon and a rotating diffraction grating. The integral multiple of the free spectral range (FSR) can be measured using a fiber-type etalon. When the range of length is greater than half of the FSR, the absolute distance can be determined with arbitrary ranges. Moreover, the limited position can be measured over a long distance. Instead of calibrating the wavelength, we use the Fabry−Perot etalon as a standard to determine the absolute position and calibrate the system. Two diffraction gratings increase the spectroscopic resolution to considerably extend the effective range of measurement. Experiments to test the proposed method indicate that it can be used to measure absolute distance with arbitrary ranges of length of up to 120 mm, with repeatability between 0.23 μm (0.0272%) and 0.77 μm (0.0619%), and can measure distances up to 1200 mm.

Detection of heavy metal ions (HMIs) in water is an important topic in the field of analytical chemistry and environmental science. Fluorescence spectroscopy is one of the most promising strategies due to its simple instrument, low investment, rapid and convenient operation. However, current fluorescence probes for detecting HMIs are typically selective for certain ions. Herein we reported the development of a novel strategy that determined the total content of HMIs in water by fluorescence spectroscopy. A novel fluorescent nitrogen, sulfur co-doped carbon quantum dots (N, S-CQDs) was prepared via graphene oxide-assisted synthesis method. The results showed that, with the fluorescence quenching strategy, N, S-CQDs exhibited a wide linear response to a series of water-soluble metal ions. The fluorescence of N, S-CQDs is stable in a wide range of pH 4-11. The detection mechanism was proved that the integration, caused by coordination interaction between S element in N, S-CQDs and the d-orbital of associated metal ions, was the main reason for fluorescence quenching. In practice, the N, S-CQDs were applied to determine total content of HMIs in water successfully. Interestingly, further experiment proved that the N, S-CQDs could effectively remove HMIs in water after centrifuging and filtering thoroughly. It was shown that the fluorescence of N, S-CQDs was obviously quenched by the multiple-ions-involved water and scavenging effect of N, S-CQDs on HMIs with centrifugal in which the concentration of individuals meets the Chinese National Standard. This indicates that the N, S-CQDs are of a wide application prospect in water quality analysis.

In this work, a novel flexible electrically resistive-type MXene/Thermoplastic polyurethanes(TPU) based strain sensors was developed by a composite process of electrospinning (ES) and electrostatic spray deposition (ESD). Compared with other deposition processes, the sensing layer prepared by ESD has better adhesion to the ES TPU nanofiber membrane and is not easy to crack during the stretching process, thereby greatly improving the working range of the strain sensor. Furthermore, we obtained the sandwich structure easily by ES on the surface of the sensing layer again. This will help make the stress distribution more uniform during the stretching process and further increase the strain sensing range. The ESD-ES strain sensors were attached on skin to monitor various human motions. The results demonstrate that our ESD-ES strain sensors have wide application prospects in smart wearable device.

We designed this retrospective study with aims to investigate the incidence and risk factors associated with surgical site infection (SSI) following posterior lumbar interbody fusion (PLIF) and instrumentation in patients with lumbar degenerative disease. Eligible patients treated between January 2016 and June 2019 were included. Electronic medical records were inquired for data extraction and collection. Patients with SSI and without SSI were compared using the univariate analyses, and the association between variables and risk of SSI was investigated using multivariate logistics regression analyses. Among 1269 patients, 43 were found to have SSI, indicating a rate of 3.4%. Microbiological culture tests showed 88.4% patients had a positive result. Four SSIs were caused by mixed bacterial, and the remaining 34 by single bacteria. Multiple drug‐resistant strains were detected in 25 (65.8%) SSIs, with meticillin‐resistant coagulase‐negative staphylococcus (MRCNS) predominating (12, 48.0%). ASA III and above (odd ratio (OR), 1.67; 95% confidence interval (CI), 1.11 to 3.07), preoperative stay (OR, 1.13; 95% CI, 1.04 to 1.23), heart disease (OR, 2.88; 95% CI, 1.24 to 6.71), diabetes mellitus (OR, 3.28; 95% CI, 1.66 to 6.47) and renal insufficiency (OR, 4.23; 95% CI, 1.26 to 10.21), prolonged prophylactic antibiotics use (OR, 4.43; 95% CI, 2.30 to 8.54), and the reduced lymphocyte count (OR, 2.11; 95% CI, 1.03 to 4.33) were identified as independent risk factors associated with SSI. These factors, although most not modifiable, should be kept in mind, optimised for surgical conditions, or readily adjusted in the future postoperative management of antibiotics, to reduce postoperative SSIs.

Surface treatment with phenols can be a new controllable anticorrosion strategy for modulating the degradation rate of magnesium implants. In our previous work, the gallic acid (GA) and the hexamethylenediamine (HD) were used to fabricate the GAHD film on the surface of magnesium and exhibited good corrosion resistance. In this work, the mechanism of anticorrosion and controllability of the GAHD film was deeply investigated. The results of SEM, EDX and XPS show that large number of magnesium was chelated into the GAHD film by GA. And the higher content the GA was, the more magnesium was chelated. Furthermore, the results of electrochemical measures and immersion tests show that the GAHD film with higher GA content possessed stronger corrosion resistance. According to these results above, we found the GAHD film deposited on the magnesium was a kind of chemical conversion coating. In the body fluid environment, massive chelated magnesium would transform into insoluble magnesium hydroxide, which are known as a natural corrosion protection substance of magnesium and perform the effect of corrosion protection. And it could easily control the corrosion resistance of the GAHD conversion coating through regulating the content of GA in the coating.

In this study, a coating of ionic Zr integrated in 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) metalorganic-like complexes was applied on Mg for corrosion control. HEDP was first immobilized on alkaline pretreated Mg followed by an alternating dip-coating process of Zr ions and HEDP to build a complex coating on Mg. This coating was demonstrated to be homogeneous, compact and with a metalorganic-like framework firmly anchored on Mg. This coating led to reduced corrosion current densities and remarkably suppressed long-term in vitro degradation of Mg in phosphate buffer saline (PBS). This complex coating showed promise for surface modification of Mg in biodegradable applications.

This paper presents a novel algorithm for partial reconstruction of the phase of an interference pattern. In multi-pulse train interferometers, the exact determination of the zero crossing position of the phase of interference fringes is important. The proposed algorithm is based on the chirp Z-transform instead of discrete Fourier transform and avoids the estimation of the whole wrapped phase of the interference pattern. In addition, to the best of our knowledge, this is the first reported method for partial reconstruction of the wrapped phase for interference fringe analysis in a pulse-train interferometer.

A new method for spectroscopic interferometry using rotating diffraction grating was developed for industrial measurements. Two diffraction gratings increase the spectroscopic resolution, and the effective measuring range can be extended considerably. Instead of calibrating the wavelength, we used the Fabry-Perot Etalon (standard) to calibrate the system and determine the absolute position. The rotation diffraction gratings may also be used as a spectroscopic element over extensive ranges for low-cost and high-speed measurement. Our experiments indicate a length range of approximately 4.00 mm with repeatability of 0.17μm (0.0167%) for the narrow range and 3.84 μm (0.0955%) for the wide range.

We propose a compressive Hadamard computational ghost imaging (CGI) method to restore clear images of objects in the underwater environment. We construct an underwater CGI system model and develop a total variation regularization prior-based compressed-sensing algorithm for the CGI image reconstruction. We design a wavelet enhancement algorithm to further denoise and enhance the quality of the CGI image. We build an experimental setup and implement a series of experiments. The effectiveness and advantages of the proposed method are experimentally investigated. The results show that the proposed method can achieve clear imaging for underwater objects with a sub-Nyquist sampling ratio. The proposed method is helpful for improving the image quality of the underwater CGI.

To address insufficient corrosion control of polymer-coated magnesium, we apply a hydrophobic stearic acid (SA) thin layer underlying the poly (lactic acid) (PLA) and poly (e-caprolactone) (PCL) coatings on Mg. The SA imbedded polymer-coated Mg showed apparently smaller corrosion current density than the direct-coated counterparts. More importantly, they exhibited manifestly slower and more stable long-term in vitro immersion degradation than the direct polymer-coated Mg up to 21 days. Moreover, the scratch testing disclosed their undercutting corrosion was suppressed evidently. The strengthened corrosion control by the imbedded layer is attributed to its kinetic barrier, hydrophobic nature as well as shielding effect.

The corrosion behavior of Zn was compared with those of Fe and Mg in a long-term course of immersing in phosphate buffered saline (PBS) as biodegradable metal for bio-implants application. The comparison focused on corrosion rate, mode, products and surface characteristics along the immersion degradation up to 21 days. For transient assays, the open circuit potential and corrosion rate placed Zn between Fe and Mg. However, in a long-term course the corrosion rate of Zinc developed faster than Fe and Mg. This was ascribed to its unique localized corrosion and corrosion products changing in contrast to Fe and Mg.

A highly sensitive and compact multi-beam angle sensor (MBAS), which utilizes the principle of operation of an autocollimator, was developed to detect the differential of the local slope components (angle difference) of a point on the mirror surface and using Fourier series, we can obtain the profile data from the angle difference. In order to investigate the application of the MBAS for high precision aspheric surface measurements, two types of calibration methods using plane mirror and cylindrical plano-convex lens has been proposed to measure the sensitivity of the MBAS. The calibration data analysis results using plane mirror agree well with the measurement results of the cylindrical plano-convex lens data. Comparison of the two methods confirms that the second method (using cylindrical plano-convex lens) is more adapted for measurement with ultra high level of uncertainty. Further, the second method is simple, corresponding to a direct calculate in the sensitive parameters aiming to minimize the cost.

Flatness tolerance of mirror is usually determined for a particular manufactured product based on the user’s requirement. To help meet this requirement, we here propose a high-accuracy microscale flatness-measuring machine (micro-FMM) that consists of a multi-beam angle sensor (MBAS). We review the techniques and the sensors predominantly used in the industry to quantify flatness. Compared with other methods, the MBAS can eliminate zero-difference error by circumferential scan and automatically eliminates the tilt error caused by the rotation of a workpiece. Our optical probe uses the principle of an autocollimator, and the flatness measurement of the mirror comprises two steps. First, the MBAS is designed to rotate around a circle with a given radius. The workpiece surface profile along this trajectory is then measured by the micro-FMM. Experimental results, confirming the suitability of the MBAS for measuring flatness are also presented.

An ultrathin bisphosphonate film, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), was deposited on magnesium for biodegradable implant applications. The small, bioactive HEDP molecule is supposed to be not only bio-safe, but also favorable for creating a highly protective layer for the control of the corrosion/degradation of Mg. In an in situ chemical sequence, the HEDP molecules were covalently surface-immobilized on the alkaline pretreated Mg and then spontaneously deposited by participation in a chelating reaction with Mg ions. An organometallic-like compound layer was thus formed, which was ascertained to be within the nanoscale and complied well with the substrate. The tape test showed that the HEDP film provides excellent adhesion strength. Electrochemical corrosion and in vitro immersion degradation investigations demonstrated that the HEDP coated Mg exhibited significantly slower corrosion rate than untreated Mg in phosphate buffered saline (PBS) solution. Of particular significance is the observation that HEDP coated Mg presented a remarkably suppressed localized corrosion mode. The meliorated corrosion/degradation behavior is credited to both the nature of the organometallic-like HEDP derivative layer, as well as the high quality of the film, with respect to compactness and homogeneity. Our HEDP modified Mg may bode well for application in biodegradable implants.

With recent development in advanced manufacturing, demand for nanometric accuracy in dimensional metrology has increased dramatically. To satisfy these requirements, we propose a high-accuracy micro-roundness measuring machine (micro-RMM) using a multi-beam angle sensor (MBAS). The micro-RMM includes three main parts: the MBAS, a rotary unit, and a bearing system. The MBAS has been designed and established in order to improve motion accuracy of the micro-RMM. The dimensions of the MBAS are 125( L ) mm × 130( W ) mm × 90( H ) mm. Compared with other methods, an MBAS is less susceptible to spindle error (stage-independence) when detecting angles, can maintain high sensitivity with miniaturized size, and can be used conveniently at the factory level. The optical probe, reported in this paper, is based on the principle of an autocollimator, and the stability is improved when using the MBAS. Unlike multi-probe methods, the micro-RMM is constructed to realize roundness measurement by using only one probe, which is less susceptible to instrumental errors. Experimental results confirming the feasibility of the multi-beam angle sensor for roundness measurement are also presented.

Spinal cannabinoid receptor 1 (CB

We propose a computational ghost imaging (CGI) scheme based on a rearranged Hadamard matrix (HCGI). A decomposition method is first introduced to construct a speckle pattern sequence that can be displayed on the digital micromirror device. Then a speckle pattern sequence rearrangement method is proposed, which makes the large intensity fluctuation values concentrate on the front part of the intensity fluctuation sequence. Finally, a HCGI model is established and a series of numerical experiments are conducted. The influence of intensity fluctuations on HCGI is studied and analyzed by comparing the numerical results which are respectively recovered by the proposed method and fast Walsh–Hadamard transform. The results demonstrate that large intensity fluctuation values play the key role in HCGI and provide maximum contribution to high quality imaging. The proposed method provides a way to improve the imaging quality and speed of CGI from the perspective of intensity fluctuations.

Reported in this paper is an investigation of the process parameter effects on surface roughness and subsurface damage (SSD) in CMP of single crystalline Silicon. For the given experiments, the appropriate method to examine the SSD can be obtained. The surface roughness and figure accuracy were measured with an atomic force microscope (AFM) and Taylor-Hobson profilometer. The experiments results indicate proper process parameter for the best surface roughness, which can be divided into two stages. It should use longer time in the finish polishing stage, while shorter time and reduce the ratio of polishing pads and head in the ultra-finish polishing stage. Generally speaking, the isotropic etching of single crystalline Silicon, anisotropic etching of single crystalline Silicon and hand burnishing are mostly used to find the SSD and it is found that the last method is the best one to see the SSD by SEM.

Magnesium metal as degradable metallic material is one of the most researched areas, but its rapid degradation rate restricts its development. The current anticorrosion surface modification methods require expensive equipment and complicated operation processes and cannot continue to introduce biofunction on modified surface. In this study, the GAHD conversion coatings were fabricated on the surface of magnesium alloys (MZM) by incubating in the mixture solution of gallic acid (GA) and hexamethylenediamine (HD) to decrease the corrosion rate and provide primary amines (-NH2), carboxyl (-COOH), and quinone groups, which is supposed to introduce biomolecules on MZM. Chemical structures of the MZM-GAHD and MZM-HEP-GAHD were explored by analyzing the results of FTIR and XPS comprehensively. Furthermore, it was proved that the heparin (HEP) molecules were successfully immobilized on MZM-GAHD surface through carbodiimide method. The evaluation of platelet adhesion and clotting time test showed that MZM-HEP-GAHD had higher anticoagulation than MZM-GAHD. Through electrochemical detection (polarization curves and electrochemical impedance spectroscopy Nyquist spectrum) and immersion test (Mg(2+) concentration and weight loss), it was proved that compared to MZM, both the MZM-GAHD and MZM-HEP-GAHD significantly improved the corrosion resistance. Finally, in vivo experimentation indicated that mass loss had no significant difference between MZM-1:1, MZM-HEP-1:1, and MZM. However, the trend still suggested that MZM-1:1 and MZM-HEP-1:1 possessed corrosion resistance property.

Biodegradable, a new revolutionary concept, is shaping the future design of biomedical implants that need to serve only as a temporary scaffold. Magnesium appears to be the most promising biodegradable metal, but challenges remain in its corrosion-controlling and uncertain biocompatibility. In this work, we employ chemical conversion and alternating dip-coating methods to anchor and deposit an Mg ion-integrated phytic acid (Mg-PA) coating on Mg, which is supposed to function both corrosion-controlling and osteo-compatible. It was ascertained that PA molecules were covalently immobilized on a chemically converted Mg(OH)2 base layer, and more PA molecules were deposited subsequently via chelating reactions with the help of additive Mg ions. The covalent immobilization and the Mg ion-supported chelating deposition contribute to a dense and homogeneous protective Mg-PA coating, which guarantees an improved corrosion resistance as well as a reduced degradation rate. Moreover, the Mg-PA coating performed osteo-compatible to promote not only bioactivity of bonelike apatite precipitation, but also induced osteoblast cells adhesion and proliferation. This is ascribed to its nature of PA molecule and the biocompatible Mg ion, both of which mimic partly the compositional structure of bone. Our magnesium ion-integrated PA-coated Mg might bode well for the future of biodegradable bone implant application.

Magnesium as well as its alloys appears increasingly as a revolutionary bio-metal for biodegradable implants application but the biggest challenges exist in its too fast bio-corrosion/degradation. Both corrosion-controllable and bio-compatible Mg-based bio-metal is highly desirable in clinic. In present work, hexamethylenediaminetetrakis (methylenephosphonic acid) [HDTMPA, (H2 O3 P-CH2 )2 -N-(CH2 )6 -N-(CH2 -PO3 H2 )2 ], as a natural and bioactive organic substance, was covalently immobilized and chelating-deposited onto Mg surface by means of chemical conversion process and dip-coating method, to fullfill dual-task performance of corrosion-protective and osteo-compatible functionalities. The chemical grafting of HDTMPA molecules, by participation of functional groups on pretreated Mg surface, ensured a firmly anchored base layer, and then sub-sequential chelating reactions of HDTMPA molecules guaranteed a homogenous and dense HDTMPA coating deposition on Mg substrate. Electrochemical corrosion and immersion degradation results reveal that the HDTMPA coated Mg provides a significantly better controlled bio-corrosion/degradation behavior in phosphate buffer saline solution as compared with untreated Mg from perspective of clinic requirement. Moreover, the HDTMPA coated Mg exhibits osteo-compatible in that it induces not only bioactivity of bone-like apatite precipitation but also promotes osteoblast cells adhesion and proliferation. Our well-controlled biodegradable and biocompatible HDTMPA modified Mg might bode well for next generation bone implant application.

Three Klebsiella pneumoniae isolates exhibiting high-level resistance to carbapenem were analysed by PCR, PFGE, gene mapping, plasmid conjugation and Southern blot hybridization using a bla KPC probe. In addition to the frequently reported bla KPC-2 and bla KPC-3 genes, a novel bla KPC-15 gene was identified in one of the isolates. The results of plasmid analysis and Southern blot hybridization revealed that the three bla KPC genes were located on transferable plasmids exhibiting three different patterns. The patterns A, B and C were observed in the genetic makeup of each individual plasmid, and all three structures contained ISKpn6-like and ISKpn8 transposons. The results of the gene mapping and hybridization experiments performed with the bla KPC probe demonstrated that the plasmids harboured the three genes at approximately the 85.0, 54.0 and 73.0 kb positions. The study concluded that carbapenem resistance in the three isolates was primarily due to the production of carbapenem-hydrolysing β-lactamase.

Conference Name:6th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies. Conference Address: Xiamen, China. Time:April 26, 2012 - April 29, 2012.