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Hemoglobin (Hb)-based oxygen carriers (HBOCs) have been investigated intensively. Enhancing the loading content of Hb in a red-blood-cell (RBC) like structure and seeking effective method to evaluate their oxygen-carrying capability have been the significant challenges. Here, we present unique biconcave Hb-Ca(OH)2 microcapsules of around 6.5 μm with high oxygen affinity using a facile and controllable method. Dextran introduced in the co-precipitation process can not only adjust the morphology of Ca(OH)2 particles but also improve the biocompatibility of the obtained microcapsules. The Hb entrapment efficiency in the microcapsules corresponded to 68% of the Hb content in one native RBC. The dynamic process of carrying-releasing oxygen of Hb-Ca(OH)2 microcapsules was investigated using electrochemical techniques. Hb in microcapsules on the surface of electrode maintained its naturally biological activity and exhibited a high ability to carry oxygen reversibly. The oxygen releasing of oxyHb-Ca(OH)2 microcapsules can be retained during at least 2400 s. The results demonstrate that Hb-Ca(OH)2 microcapsules with highly loaded content possessed excellent function of oxygen-binding and releasing, which make it promising for applications in artificial oxygen carriers and other biomedical fields.

The authors demonstrate a multivalent recognition and triple signal amplification strategy for amperometric cytosensing and dynamic evaluation of cell surface sialic acid (SA). The strategy is based on the use of (a) graphene oxide functionalized with 3-aminophenylboronic acid (APBA-CG) for cell capture, and (b) of Sambucus nigra agglutinin and thionine conjugated to gold nanoparticles (SNA-AuNP-Th) acting as a nanoprobe. The use of APBA-CG accelerates electron transfer and warrant a large surface area for cell capture. The AuNPs, in turn, nanoprobe provide an effective matrix for mass loading of thionine molecules and thus dramatically improve sensitivity. The results obtained with the biosensor demonstrate that sialic acid is strongly expressed levels in cancer cells compared to normal ones. The cytosensor was applied to the detection of HepG2 cells. Best operated at a working voltage of typically 0.42 V vs. Ag/AgCl, it displays a wide linear range (that extends from 1.0 × 102 to 1.0 × 107 cells per mL and a low detection limit (50 cells per mL)). The method was successfully applied dynamic monitoring of the changes in cell surface SA expression in response to the addition of the enzyme sialidase. In our perception, the SNA-based biosensor represents a viable tool to study SA-related biological processes and for diagnosis and treatment of early stages of cancer.

Core-shell Au@Ag nanorods (Ag@GNRs) were synthesized and utilized to construct a voltammetric biosensor for trichloroacetic acid (TCA). The biosensor was prepared by immobilizing hemoglobin (Hb) on a glassy carbon electrode (GCE) that was modified with the Ag@GNRs. Cyclic voltammetry revealed a pair of symmetric redox peaks, indicating that direct electron transfer occurs at the Hb on the Ag@GNR-film. The electron transfer rate constant is as high as 2.32 s−1. The good electrocatalytic capability and large surface area of the Ag@GNR-film is beneficial in terms of electron transfer between Hb and the underlying electrode. The modified GCE, best operated at −0.4 V (vs. SCE), exhibits electrocatalytic activity toward TCA in the 0.16 μM to 1.7 μM concentration range, with a 0.12 μM detection limit (at an S/N ratio of 3).

This study describes an amperometric sensor for hydrogen peroxide (H2O2) that uses an ITO glass electrode which was modified with a nanocomposite consisting of electrochemically reduced graphene oxide and gold nanoclusters (AuNCs). The sensor was used to quantify extracellular H2O2 released from human neuroblastoma cells of type SH-SY5Y. The calibration plot, established best at a working voltage of −0.4 V (vs. Ag/AgCl) is linear in the 40 nmol⋅L−1 to 2 μmol⋅L−1 concentration range, and the detection limit is 20 nmol⋅L−1 (at a signal-to-noise ratio of 3). The method was further applied to study bupivacaine-induced cell damage and the protective effects of α-lipoic acid. The study indicated that pretreatment of the cells with lipoic acid retards cell damage induced by bupivacaine. The sensor can be easily fabricated, is disposable and highly sensitive. The sensor is perceived to represent an alternative for studying the interactions of drugs with cells, and as an effective tool to quantify cell-secreted H2O2.

In this work, an origami paper-based analytical device for glucose biosensor by employing fully-drawn pencil electrodes has been reported. The three-electrode system was prepared on paper directly by drawing with nothing more than pencils. By simple printing, two separated zones on paper were designed for the immobilization of the mediator and glucose oxidase (GOx), respectively. The used paper provides a favorable and biocompatible support for maintaining the bioactivities of GOx. With a sandwich-type scheme, the origami biosensor exhibited great analytical performance for glucose sensing including acceptable reproducibility and favorable selectivity against common interferents in physiological fluids. The limit of detection and linear range achieved with the approach was 0.05 mM and 1–12 mM, respectively. Its analytical performance was also demonstrated in the analysis of human blood samples. Such fully-drawn paper-based device is cheap, flexible, portable, disposable, and environmentally friendly, affording great convenience for practical use under resource-limited conditions. We therefore envision that this approach can be extended to generate other functional paper-based devices.

In this paper, a facile and low-cost “pencil-drawing” method is exploited for writing electrodes on filter paper to fabricate an electrochemical paper-based analytical device. Unlike other techniques using inks or pastes, the three-electrode system can be prepared directly by drawing with nothing more than pencils and paper. The optimization using ferricyanide as the redox probe showed that the device fully drawn with 6B grade pencil possesses excellent electrochemical properties and sensor-to-sensor reproducibility in spite of its truly simple fabrication process. Experimental results demonstrated that the proposed device could be utilized for quantification of dopamine with high sensitivity and no interference from ascorbic acid and uric acid, which are normally present in biological fluids. Human urine and blood serum samples were analyzed using the proposed device as proof of concept. Such fully-drawn sensors are flexible, portable and disposable, represent a cheap and environmentally friendly approach that can be rapidly and easily fabricated without any specialized materials, affording great convenience for practical use in resource-limited or emergency situations.

Polydopamine-hemoglobin (PDA-Hb) microcapsules as suitable oxygen carriers are fabricated easily by templating decomposable MnCO3 particles in collaboration with self-polymerization of dopamine on pure Hb spheres. The PDA-Hb microcapsules possess a high oxygen affinity and are able to bind and release oxygen reversibly as demonstrated by electrochemical methods.

The paper established a differential equation of a new vibration screen which with a monaxial vibration motor was set transversely. Based on Particle Swarm Optimization(PSO), the equation was analysed, and the motion equation and the tracing equation were obtained. The discussed of these equations indicated the swing of the sifter body was around its centroid, and the motion trajectory of any point on the sifter body was ellipse. Then, the theoretical research on vibration screen was carried on, and the connections of displacement with parameters were gained.

The research on real time fruit quality detection with machine vision is an attractive and prospective subject for improving marketing competition and post harvesting value-added processing technology of fruit products. However, the farm products with different varieties and different quality have caused tremendous losses in economy due to lacking the post-harvest inspecting standards and measures in China. In view of the existing situations of fruit quality detection and the broad application prospect of machine vision in quality evaluation of agricultural products in China, the methods to detect the external quality of pear by machine vision were researched in this work. It aims at solving the problems, such as fast processing the large amount of image information, processing capability and increasing precision of detection, etc. The research is supported by the software of Lab Windows/CVI of NI Company. The system can be used for fruit grading by the external qualities of size, shape, color and surface defects. Some fundamental theories of machine vision based on virtual instrumentation were investigated and developed in this work. It is testified that machine vision is an alternative to unreliable manual sorting of fruits.

The super-resolution (SR) method is a method which used a sequence of low-resolution images (LR)to restore a frame or a sequence of good high resolution images (HR). Based on the characteristic of the micro-displacement between a sequence of low resolution images, to deduce the gray iterative expressions. Two improved methods are arisen from the method; it makes the restored images better. And in the course of improving, a new image quality evaluation method based on texture analysis is presented. After this method comparing with Mean squared error (MSE), it is known that this new method was better than MSE. So in the two kinds of improved SR methods, the new image quality evaluation method is as aim function to get parameters for best SR restored image. Finally, experimental results show that the method properly retrieves details of images, and subjective visual effect of the restored images is improved significantly.

This paper has developed a new-type groundwater dynamic auto-monitoring system based on Smart Device. The system adopted Smart Device as host computer of data acquisition, used Windows Mobile which was prevalent operation system of Smart Device now, software development environment Visual Studio.NET 2003, and C# as the developing language based on .NET framework. It adopted serial port RS232 as the communication interface between Smart Device and monitor host machine and utilized multi-threading design to achieve serial port communication. It adopted the standardized and textual XML to store the data. And this system implemented the function of data acquiring, file managing, and analysing and displaying. In virtue of fully considerations in characteristic of Smart Device, this system had the succinct window interface, simply operation, powerful function, and was very convenient to carry. Moreover it has already made very good use result in practice.

At present, image processing technology is more commonly applied to such fields as virtual reality and biological medicine, and permeates rapidly through agricultural scientific research. The image measuring method makes dairy cow type linear appraisal , which not only reduces workload but also gets rid of the shortcoming of the manual appraisal standard changing with human and time and the disadvantage of lacking impersonal impartiality. This paper describes a linear appraisal system for analyzing dairy cow types based on image processing, which consists of hardware design, software design, realization of characters click points operating and the interactive measurement of type character parameter for dairy cow. We use NI IMAQ Vision and NI Lab Windows/CVI 6.0 to develop the system software. The central purpose of image preconditioning is to clear up noise, and we use median filtering to eliminate noise in this approach.

The paper designed a new groundwater-monitoring instrument based on the technology of wireless-sensor net. The new instrument monitors groundwater table and temperature through a sensor. An embedded singlechip processes the monitoring data and TC35, a GSM data module transfers the data wirelessly. Above mentioned compose the whole intelligent sensor net. The intelligent network sensor has the function of self-recognition and self-adjustment, meanwhile realizes the non-linearity compensating of sensor by using software technology. The wireless transmission module takes the low power loss AT89C51 chip as a core and has realized bidirectional communication between central node and sensor. The wireless sensor net adopts star topology and its central node may communicate with any ordinary nodes. The system has self-diagnosis function, once appears fault, the monitor system can receive the fault alarm and report automatically. This paper takes GSM public net as data transmission net and provides the convenience for system expansion and maintenance.

This paper describes an approach to digit recognition for the serial numbers on the Chinese currency banknotes. The approach consists of a number of components including image preprocessing, image binarisation, morphological filtering, segmentation, feature extraction and digit recognition. The approach was examined and tested on 5000 banknotes with 4000 digits and the approach achieved s single digit recognition rate of more than 99.60%, a serial number recognition rate of 99.50%, and a recognition time of 157 ms. The results show that this approach is effective and efficient and can clearly meet the system requirements.

This paper describes an approach to online simplification of evolved programs in genetic programming (GP). Rather than manually simplifying genetic programs after evolution for interpretation purposes only, this approach automatically simplifies programs during evolution. In this approach, algebraic simplification rules, algebraic equivalence and prime techniques are used to simplify genetic programs. The simplification based GP system is examined and compared to a standard GP system on a regression problem and a classification problem. The results suggest that, at certain frequencies or proportions, this system can not only achieve superior performance to the standard system on these problems, but also significantly reduce the sizes of evolved programs.

The mathematics model of environment temperature is established based on the fuzzy arithmetic theory. It deals with the problems of traditional animal building, such as outdated management, high cost, low-level automation, etc. The system measures the environment parameters based on PCI-DAQ virtual instrument data acquisition system, transmits the data by 32 bits parallel bus, and adjusts the rotate speed by frequency conversion devices. It is used to run in real environment, the original environment temperature is 30., and the given value is 27..The precision is within ±0.5.. And it also monitors and controls the temperature parameter real-timely based on fuzzy control technology. Compared with the traditional PID control system, it can increase the stability of system, avoid the subjectivity and random of manual operation, and improve precision and efficiency of the whole system. The system has high practical value and prospect of using since it meets the request of scientific producing and automatic management of animal building.