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With consumer concerns increasing over food quality and safety, the food industry has begun to pay much more attention to the development of rapid and reliable food-evaluation systems over the years. As a result, there is a great need for manufacturers and retailers to operate effective real-time assessments for food quality and safety during food production and processing. Computer vision, comprising a nondestructive assessment approach, has the aptitude to estimate the characteristics of food products with its advantages of fast speed, ease of use, and minimal sample preparation. Specifically, computer vision systems are feasible for classifying food products into specific grades, detecting defects, and estimating properties such as color, shape, size, surface defects, and contamination. Therefore, in order to track the latest research developments of this technology in the agri-food industry, this review aims to present the fundamentals and instrumentation of computer vision systems with details of applications in quality assessment of agri-food products from 2007 to 2013 and also discuss its future trends in combination with spectroscopy. [ABSTRACT FROM PUBLISHER]

Objective: To investigate the inhibitory effect of bone marrow mesenchymal stem cells (BMSCs) on E coliinduced prostatitis in rats., Methods: BMSCs were isolated, cultured and amplified by the attached choice method. Fifty SD rats were randomized into five groups of equal number: normal control, acute bacterial prostatitis (ABP) , chronic bacterial prostatitis (CBP), ABP + BMSCs, and CBP + BMSCs, and the animals in the latter four groups were injected with E. coli into both sides of the prostate under ultrasound guidance for 1 - 14 days to induce ABP and for 4 - 12 weeks to induce CBP. The control rats were injected with the same amount of PBS. Two weeks after injection of BMSCs into the prostates, pathomorphological changes in the prostate were observed under the light microscope and the mRNA and protein levels of IL-1β and TNF-α determined by RT-PCR and ELISA, respectively, followed by statistical analysis with SPSS 18.0., Results: Histopathological evaluation showed typical pathological inflammatory changes in the prostates of the rats in the ABP and CBP groups, including glandular structural changes, interstitial edema, inflammatory cell infiltration, and fibrous hyperplasia, which were all remarkably relieved after treated with BMSCs. The mRNA and protein levels of IL-β ([0.829 ± 0.121] and [271.75 ± 90.59] pg/ml) and TNF-α ([0.913 ± 0. 094] and [105.78 ± 19. 05] pg/ml) in the ABP and those of IL-1β ([0. 975 ± 0. 114] and [265. 31 ± 71. 34] pg/ml) and TNF-α ([0. 886 ± 0. 084] and [107. 45 ± 26. 11 ] pg/ml) in the CBP groups were significantly higher than those in the control rats ([0. 342 ± 0.087] and [45.76 17. 99] pg/ml, P <0. 05); ([0.247 ± 0.054] and ([19.42 ± 7. 75] pg/ml, P <0. 01) as well as than those in the ABP + BMSCs ([0. 433 ± 0. 072] and [51. 34 ± 22. 13] pg/ml, P < 0. 05 ) ; ( [0. 313 ± 0. 076] and [28. 38 ± 8. 78] pg/ml, P < 0. 01) and the CBP + BMSCs group ([0.396 ± 0.064] and [56.37 ± 21.22] pg/ml, P <0.05); ([0.417 ± 0.068] and [29.21 ± 10.22] pg/ml, P <0.01)., Conclusion: Injection of BMSCs can reduce E coli-induced prostatic inflammation reaction, which.may be associated with its reduction of inflammatory cell infiltration and the expressions of IL-1β and TNF-α in the prostate tissue.

Speckle suppression has been the research focus in laser display technology. In the present paper, the relation between multiple scattering and the size of speckle grains is established by analyzing the properties of speckle generated by the laser beam through SiO2 suspension. Combined with dynamic light scattering theory, laser speckle suppression due to dynamic multiple scattering scheme introduced by oblique incidence is proposed. A speckle suppression element consists of a static diffuser and a light pipe containing the water suspension of SiO2 microspheres with a diameter of 300 nm and a molar concentration of 3.0 x 10(-4) μm3, which is integrated with the laser display system. The laser beam with different incident angles into the SiO2 suspension affecting the contrast of the speckle images is analyzed by the experiments. The results demonstrate that the contrast of the speckle image can be reduced to 0.067 from 0.43 when the beam with the incident angle of approximately 8 degrees illuminates into the SiO2 suspension. The spatial average of speckle granules and the temporal average of speckle images were achieved by the proposed method, which improved the effect of speckle suppression. The proposed element for speckle suppression improved the reliability and reduced the cost of laser projection system, since no mechanical vibration is needed and it is convenient to integrate the element with the existing projection system.

According to the requirements of infrared gas sensor for the light source, a broad wavelength, high modulation frequency, low power consumption and small size MEMS infrared light source is chosen as the radiation source, whose performance meets the requirements of infrared sensing system for the light source greatly. However, the infrared light source with the lamberation radiation characteristics is a surface light source, which is still with a large numerical aperture after shaping. It is difficult to increase the detection sensitivity by using a traditional long optical gas cell in a MEMS infrared light source detection system. Based on the dual-wavelength single beam differential detection method, an integrating sphere as the gas cell for long optical path is designed, which is able to realize long optical path for high sensitivity gas detection. The physical dimension is deduced for the equivalent optical path according to the flux conservation principle in the process of light transmission, solving the calculation problem of equivalent optical path of the integrating sphere cell. Using FPGA control chip, the MEMS infrared light source is droved at high frequency modulation and the detector output signal is processed, which makes the external circuit design much simple and flexible. It turns out that 166.7 cm equivalent optical path and the minimum concentration of methane of 0.001 x 10(-6) are achieved by the use of a 5 cm diameter integrating sphere in the research, improving the sensitivity of infrared detection system greatly.

Objective: To explore the feasibility of disrupting tumor microcirculation by the cavitation of microbubbles enhanced ultrasound (US) and analyze its pathological mechanism., Methods: Twenty-four SD male rats with subcutaneously transplanted Walker-256 tumor were divided into 3 groups, i.e. ultrasound plus microbubbles group (US + MB), US group and sham group. Pulsed US was delivered to tumor for 3 minutes during an intravenous infusion of microbubbles at 0.2 ml/kg in the US + MB group. The control groups received only the US exposure or the MB injection. Tumor perfusion was visualized with contrast enhanced ultrasound before and 0 min after treatment. Finally the pathological examination was performed., Results: The contrast perfusion of Walker-256 tumors vanished immediately after treatment in the US + MB group and the gray scale value (GSV) decreased from 121 ± 12 (pre-treatment) to 81 ± 9 (post-treatment, P < 0.01). There was no significant difference of GSV before and after treatment in two control groups (P > 0.05). The GSV values were 112 ± 14 and 111 ± 12 pre-treatment and 113 ± 14 and 103 ± 13 post-treatment in the sham and US groups. The pathological examination showed remarkable hemorrhage, endothelial injuries, increased intercellular edema and in situ thrombosis., Conclusion: Microbubble-enhanced ultrasound can significantly disrupt tumor vasculature and block its circulation. And it may become a novel physical anti-angiogenetic therapy for tumor.

Objective: To identify the association strength of the prevalence of HBeAg, covalently closed circular DNA (cccDNA) and 1762/1764 nucleotide mutations of hepatitis B virus (HBV) with the occurrence of hepatocellular carcinoma (HCC) in Qidong high risk male cohort., Methods: A cohort of 377 middle aged HBV infected men in Qidong was followed from January 1989 to December 2002. Incident HCC cases were carefully registered. A matched case-controlled study was conducted on 32 pairs of inherent HCC cases with their matched non-HCC controls. Serum HBeAg was measured by ELISA. cccDNA was detected by primer selected PCR. 1762/1764 nucleotide mutations of HBV was identified by PCR of X gene segment spanning the mutation region. Standard statistical comparison between the prevalence of each HBV marker in HCC versus in control group provided the odds ratio with P value to evaluate its association strength with HCC occurrence., Results: Serum HBeAg prevalence was 53.1% (17/32) in HCC group versus and 15.6% (5/32) in controls (OR = 6.12, P < 0.01). Prevalence of serum cccDNA was detected in 62.5% (21/32) of HCC cases but in 25.0% (8/32) of controls (OR = 5.73, P < 0.01). Sequence of detected cccDNA was repeatedly found to be over 90% homologous with HBV. However, the mutation rate of nucleotide 1762/1764 was not found to be statistically higher in the HCC group versus its controls (OR = 1.54, P = 0.425)., Conclusions: The Qidong male case-controlled cohort had shown that serum HBeAg and cccDNA prevalence were tightly associated with hepatocellular carcinoma occurrence in HBV infected men. These biomarkers may have predictive value in earlier diagnosis and therapeutic effect monitoring.

Background: Hepatocellular carcinoma (HCC) is the second most common cancer in China. Hepatitis B and C viruses (HBV and HCV) and aflatoxins are known risk factors for HCC, but the etiological status of these factors in HCC development is not clear. This study was undertaken to define the absolute importance of HBV in hepatocarcinogenesis of North China., Methods: A consecutive series of 119 patients with pathologically proven HCC were collected from North China during January 1998 to December 2000 by the Cancer Hospital of the Chinese Academy of Medical Sciences, Beijing. Serum HBsAg, anti-HBc and anti-HCV were negative HBV sero-markers. The HBV X gene was analyzed for its expression by PCR, DNA sequencing, and immunohistochemistry., Results: In the 119 HCC patients, 82.4% (98/119) were HBsAg seropositive. When a comprehensive set of HBV markers were detected, the HBV infection rate in these HCC patients was 99.2% (118/119). Of the patients, 11.8%(14/119) were found to be anti-HCV positive. But all the anti-HCV positive HCC patients were co-infected with HBV., Conclusions: HBV infection is virtually ubiquitous in HCC patients in North China. The tight association of HBV with HCC strongly suggests the dominant role of HBV infection in causing hepatocellular carcinoma. About 11.8% of HCC patients being HCV-related are co-infected with HBV.