Rapid and standardized methods for detection of foodborne pathogens and mycotoxins on fresh produce

Due to the increase in consumption of fresh produce regarding to the health demand in the last decades, a considerable portion of foodborne outbreaks has been trackbacked to contaminated fresh produce, which have appeared as highly possible vehicles for foodborne outbreaks nowadays. Delays in detection of pathogens and mycotoxins on fresh produce hindered the trace-back investigations in finding the source and revealed the urgent need of rapid and reliable methods. In the frame of this review, we summarized available fast, reliable and standardized methods (conventional, molecular, rapid and recently developed methods) used for detection of the most common foodborne pathogens and mycotoxins which are the most likely causative agents of outbreaks caused by contaminated fresh produce.     

基于FPGA的激光探测自适应电路设计

激光以其方向性好、亮度高、单色性好等优点使得其应用越来越广泛，但是，因其受环境条件的影响较大，特别是在沙尘、雨雪、雾霾等不同天气情况下，激光探测性能受到很大干扰，该文针对这种状况，基于 FPGA 设计了激光探测自适应电路，表明随着传感信号输入的变化，则相应的阈值门限也随之变化，使得不同阈值对噪声的抑制能力达到最佳，从而达到一个自动调节、动态平衡的效果。     

Mapping and mining interictal pathological gamma (30-100 Hz) oscillations with clinical intracranial EEG in patients with epilepsy

Localizing an epileptic network is essential for guiding neurosurgery and antiepileptic medical devices as well as elucidating mechanisms that may explain seizure-generation and epilepsy. There is increasing evidence that pathological oscillations may be specific to diseased networks in patients with epilepsy and that these oscillations may be a key biomarker for generating and indentifying epileptic networks. We present a semi-automated method that detects, maps, and mines pathological gamma (30-100 Hz) oscillations (PGOs) in human epileptic brain to possibly localize epileptic networks. We apply the method to standard clinical iEEG (<100 Hz) with interictal PGOs and seizures from six patients with medically refractory epilepsy. We demonstrate that electrodes with consistent PGO discharges do not always coincide with clinically determined seizure onset zone (SOZ) electrodes but at times PGO-dense electrodes include secondary seizure-areas (SS) or even areas without seizures (NS). In 4/5 patients with epilepsy surgery, we observe poor (Engel Class 4) postsurgical outcomes and identify more PGO-activity in SS or NS than in SOZ. Additional studies are needed to further clarify the role of PGOs in epileptic brain.     

Auto-microfluidic thin-film chip for genetically modified maize detection

As a thin-film chip method, reverse dot blot hybridization (RDBH) has been employed to detect hazardous substances, but an automatic RDBH instrument with low workload, high accuracy and stability is still urgently needed. This paper presents our newly-developed auto-microfluidic thin-film chip (AMTC) method for multiplex screening of genetically modified (GM) maize. With specific DNA probes for genetically modified (GM) maize being immobilized on a square nylon thin-film, it was placed into a micro-reaction cell of the AMTC device. Then biotin-labeled PCR products with target DNA fragments for template amplification were added to the micro-reaction cell using a microfluidic system. When the PCR products passed the square nylon thin-film, the target DNA fragments were captured by the complementary action of DNA, where the signal was visualized with streptavidin link-coupled alkaline phosphatase color development kit. The sensitivity of GM maize detection reached 0.1% quality percentage and its stability and consistency could satisfy the requirements for practical applications. Performance advantages of the ATMC are manifold, being embodied in aspects such as easy and straightforward operation, low costs and less workload.     

提高螺旋焊管超声波检测准确率的方法探讨

针对压力管道元件（螺旋焊管）制造单位存在超声波检测时缺陷检出率较低,导致生产的螺旋焊管质量不满足制造标准要求但却出厂的问题,通过对探头K值的研究,确定进行缺陷准确定位的探头选取原则以及对发现的缺陷进行定位的方法,为产品检验及监检人员审查螺旋焊管超声波检测报告的准确性和真实性提供了依据,减少了不合格产品出厂的几率。     

纯电动汽车动力电池性能测试方法研究

随着全球能源危机及环境污染日益严重,电动汽车已逐步成为汽车未来发展方向之一。针对电动汽车核心部分动力电池组,建立相关的动力电池性能测试方法,通过此测试方法可获得汽车在实际运行工况下动力电池的真实性能状态,提高对动力电池性能参数的检测精度,为以后建立完整的电动汽车性能测试提供一定的参考依据。     

遥感-岩石力学在矿山应用的试验研究

遥感-岩石力学的试验研究表明,岩石在受力与灾变过程中存在特征性的红外辐射变化,利用红外手段可以监测岩石应力与灾变问题。在过去遥感-岩石力学试验研究的基础上,针对矿山与岩石破裂失稳有关的安全隐患问题,利用红外热像仪对河北省峪耳崖金矿和辽宁省齐大山铁矿进行了现场检测,结果表明,利用热像仪可以检测井下高矿压部位、冒落和片帮等危险性的部位、渗水部位以及露天矿中断层和滑坡危险区,这些区域在热像中呈现不同于周围正常岩石的温度色调。如果结合长时间动态观测,可以对这些矿山灾害进行预测预警。研究结果为矿山安全及防灾减灾提供了新的监测预警手段。     

基于帧差法的矿用皮带机运动检测

 对于矿用皮带机的运动检测,要求计算快速、实时处理。但由于井下环境复杂,可辨信息量少,采集到的视频图像有明显的光照和噪声干扰,在检测时会造成一定的误差。针对上述问题,本文提出了一种基于帧差法的皮带运动检测方法,在满足检测需求的同时,结合了井下视频图像的特点,对图像的进行分割,排除干扰区域,从而可以准确、快速地判断皮带的运动情况。     

过老巷安全技术探讨

小煤窑老巷破坏区内的积水及聚积的瓦斯是整合矿井巷道掘进过程中的主要威胁,本文以山西泽州天泰坤达煤业有限公司整合矿井为背景,通过对小煤窑老巷破坏区地质条件分析得知,废弃老巷内有大量积水及瓦斯积聚,对巷道掘进造成极大的安全隐患。为了保障待掘巷道能够安全快速地通过老巷破坏区,提出了安全通过老巷破坏区的探放水措施及老巷瓦斯治理措施。     

Specific detection of viable Listeria monocytogenes in Spanish wastewater treatment plants by Fluorescent In Situ Hybridization and PCR

Listeria monocytogenes detection in wastewater can be difficult because of the large amount of background microbiota and the presence of viable but non-culturable forms in this environment. The aim of this study was to evaluate a Fluorescent In Situ Hybridization (FISH) assay combined with Direct Viable Count (DVC) method for detecting viable L. monocytogenes in wastewater samples, as an alternative to conventional culture methods. 16S rRNA sequence data were used to design a specific oligonucleotide probe. In order to assess the suitability of the method, the assays were performed on naturally (n = 87) and artificially (n = 14) contaminated samples and results were compared to those obtained with the isolation of cells on selective media and with a PCR method. The detection limit of FISH and PCR assays was 10⁴ cells/mL without enrichment and 10 cells/mL after enrichment. A total of 47 samples, including 3 samples from effluent sites, yielded FISH positive results for L. monocytogenes. Using DVC-FISH technique, the presence of viable L. monocytogenes cells was detected in 23 out of these 47 FISH positive wastewater samples. PCR and culture methods yielded 27 and 23 positive results, respectively. According to these results, FISH technique has the potential to be used as a sensitive method for the detection and enumeration of L. monocytogenes in environmental wastewater samples.