On-line scheme for computing rotation factors

An integrated radix-2 on-line algorithm for computing rotation factors for matrix transformations is presented. The inputs are in sign-and-magnitude, floating-point representation and the outputs can be used in on-line signed-digit or in parallel form. The exponents are computed using conventional arithmetic while the significands are processed using on-line algorithms. The conventional result is obtained by using an on-the-fly conversion scheme. The rotation factors are computed in 10 + n clock cycles for n-bit significands. The clock period is kept small by the use of redundant adder schemes and low-precision estimates. The implementation and performance of the algorithm are discussed and compared with other approaches.     

Reduction of mutagenicity of the fumes from cooking oil by degumming treatment

The fume of cooking oil has been reported to increase the risk of respiratory tract cancer. The influence of a degumming treatment of peanut oil on the contents of mutagenic compounds in fumes from heated peanut oil was investigated. The results indicate that the peanut oil prepared from roasted peanut kernels which underwent degumming treatment had a lower free fatty acid (FFA) content and a higher smoke point, was more clear in color, and produced less fumes when heated at smoke point. Moreover, when compared to untreated peanut oil, the mutagenicity of oil fumes of degummed peanut oil toward Salmonella typhimurium TA98 and TA100 was reduced to 81% and 73% (p<0.05), respectively. The degummed peanut oil which was obtained by adding 3% water and heating at 60°C for 20 min produced the least amount of mutagenic fume. The contents of four mutagenic compounds, trans-trans-2,4-decadienal (t-t-2,4-DDE), trans-trans-2,4-nonadienal (t-t-2,4-NDE), trans-2-decenal (t-2-DCA), and trans-2-undecenal (t-2-UDA) in oil fumes of degummed peanut oils were drastically decreased (p<0.05), especially the t-t-2,4-DDE. The results also indicate that the FFA content had a high linear correlation with mutagenicity (r²=0.9978) and content of t-t-2,4-DDE (r²=0.7685). Moreover, there was a correlation (r²=0.7816) between the content and the mutagenicity of t-t-2,4-DDE. The decrease of FFA by degumming might explain the reduction of mutagenic alkenal compounds and mutagenicity of fumes from heated peanut oil.     

米糠不溶性膳食纤维对慢性镉暴露小鼠的保护作用

该研究探讨了米糠不溶性膳食纤维（rice bran insoluble dietary fiber,RBIDF）对慢性镉暴露小鼠的保护作用。对大肠埃希菌进行体外培养,观察镉对细菌生长的影响以及RBIDF对镉的吸附作用;将小鼠分为阴性对照组、阳性对照组及RBIDF处理组,喂养8周后检测其组织、血液和粪便中镉的含量以及粪便中短链脂肪酸（short chain fatty acids,SCFAs）的含量,并提取粪便中肠道菌群DNA进行高通量测序和荧光定量PCR检测。结果显示,RBIDF可以吸附镉,保护大肠埃希菌的生长;与阳性对照组相比,RBIDF处理组小鼠血液中镉含量下降了66.67%、肝脏中下降了57.67%、小肠中下降了27.15%、粪便中增加了60.64%,粪便中三种SCFAs含量分别增加到1.30倍、2.25倍、2.75倍,并且肠道细菌总量增加到1.40倍。此外,在门水平上,RBIDF处理组肠道菌群结构与阴性对照组相似,以拟杆菌门（68.75%）、厚壁菌门（23.67%）和变形菌门（6.82%）为主,而阳性对照组以拟杆菌门（55.71%）、厚壁菌门（33.25%）、疣微菌门（5.62%）为主。这些结果表明,RBIDF可以吸附镉,降低小鼠组织血液中的镉浓度,促进小鼠肠道菌群恢复,对慢性镉暴露小鼠具有保护作用。     

自来水中余氯和亚硝酸盐含量与加热条件的相关性研究

目的研究自来水在不同加热方式下余氯及亚硝酸盐含量的变化,为人们日常健康饮水提供理论依据。方法根据国家标准GB 5750.5-2006和GB 5750.11-2006,对管网末梢水在经过不同煮沸时间、不同煮沸次数、煮沸后不同放置时间以及自动开水器及家用电水煲烧开的水中的余氯和亚硝酸盐含量进行检测。结果市政自来水中余氯含量为0.25 mg/L,亚硝酸盐含量未检出。自来水在煮沸1 min之后余氯含量未检出,而用家用电水煲烧开的水中余氯为0.1 mg/L,煮沸1 h,含量达到3.80μg/L,在国家标准限值之下。开水放置24 h亚硝酸盐含量达2.37μg/L,继续加热1 min后,含量再次升高达2.76μg/L。自来水反复煮沸8次后,亚硝酸盐含量达3.38μg/L。自动开水器烧开的自来水中余氯上午偏高,早上和晚上则未检出;亚硝酸盐含量在上午和晚上偏低,在早上含量明显升高。结论市政自来水通过加热,较高的余氯迅速挥发减少,而亚硝酸盐含量则会增加。家用电水煲开水中余氯残留较多,在使用家用电水煲时,建议电水煲断电后再开盖烧1 min。取公共场所自动开水器的水时,尽量避免在用水高峰时取水。     

黄精水提物干预脂多糖诱导的巨噬细胞极化与自噬研究

目的 探讨黄精水提物(Polygonatum sibiricum aqueous extract, PSAE)对脂多糖(lipopolysaccharides, LPS)诱导的RAW264.7巨噬细胞M1极化与自噬的调节作用, 探究其抗炎机制。方法 实验分为对照组(无任何处理)、LPS组(100 ng/mL LPS刺激12 h)、PSAE低、中、高剂量组(50、100、200 μg/mL PSAE预处理细胞 4 h后, 再加入100 ng/mL LPS刺激12 h)。细胞计数(cell counting kit-8, CCK-8)法检测细胞活性; Griess法检测细胞NO分泌量; 实时荧光定量PCR检测细胞诱导型NO合酶(inducible nitric oxide synthase, iNOS)、白细胞介素-1β (interleukin-1β, IL-1β)、肿瘤坏死因子-α (tumor necrosis factor-α, TNF-α)及单核细胞趋化蛋白-1 (monocyte chemotactic protein-1, MCP-1)的mRNA水平; 蛋白质免疫印迹和免疫荧光法检测M1型极化标志物iNOS表达水平; 蛋白质免疫印迹检测微管相关蛋白1轻链3 (microtubule-associated protein 1 light chain 3, LC3)和螯合体1 (sequestosome 1, p62)表达水平。结果 与LPS组相比, PSAE可使RAW264.7细胞NO的分泌减少(P<0.05, P<0.01), PSAE也可降低M1极化相关炎症因子(iNOS、IL-1β、TNF-α、MCP-1) mRNA表达水平(P<0.05, P<0.01, P<0.001), 降低M1极化标志物iNOS蛋白表达水平(P<0.05, P<0.001), 同时, PSAE可降低LC3II/I值(P<0.01, P<0.001), 促进p62蛋白表达(P<0.01), 从而降低自噬水平。结论 PSAE能够抑制LPS诱导的RAW264.7细胞M1极化和自噬水平, 减轻细胞炎症反应。     

邻苯二甲酸二（2-乙基己基）酯在青春期小鼠体内的代谢动力学研究

研究邻苯二甲酸二（2-乙基己基）酯（di-（2-ethylhexyl）phthalate,DEHP）在青春期小鼠体内的代谢动力学,以300 mg/kg DEHP灌胃青春期小鼠,血清样品经固相萃取（solid phase extraction,SPE）提取和净化,气相色谱-质谱联用（gas chromatography-mass spectrometry,GC-MS）法测定不同时间点的血药质量浓度,以3p97软件拟合其动力学参数。DEHP在青春期小鼠体内的主要药物代谢动力学参数：药峰质量浓度ρmax为（0.476±0.028） μg/mL,达峰时间Tpeak为（2.539±0.424） h,药-时曲线下面积AUC（0-t）为（32.209±11.220） h•μg/mL,分布半衰期t1/2α为（1.886±0.480） h,消除半衰期t1/2β为（36.473±8.324） h。本方法简便快捷,其灵敏度和准确度均可满足青春期小鼠体内DEHP代谢动力学研究。DEHP在青春期小鼠体内药物代谢动力学过程符合一级吸收二室开放模型,其分布较快,代谢较慢。     

安徽省《预包装食品标签通则》跟踪调查

目的了解安徽省生产企业、监管机构、检验机构、科研院所专家对GB 7718—2011《预包装食品标签通则》的执行能力、理解能力和依从性,为标准实施和修订建议提供依据。方法采用横断面调查法,2013年7~10月本研究组通过组织会议、电子邮件、传真等多种途径开展问卷调查。调查对象选取安徽省区域内的生产企业、监管机构、检验机构和科研院所的专家,收集标准执行过程中遇到的主要问题、对标准条款的理解以及意见和建议。结果生产企业、监管机构、检验机构和科研院所回收的有效问卷分别为35、25、28和12份,收集的反馈意见分别为46、28、22和17条;标准的知晓率为92.0%;不同部门均认为标准的整体合理程度较高(分别为87.8%、83.3%、91.3%、100%),可操作性较强(分别为87.9%、87.5%、86.9%、100%);生产企业和监管机构的人员使用标准的频率较高;针对具体条款直接向消费者提供的预包装食品标签标示内容致敏物质改为强制标示食品添加剂在配料表中的标示形式等反馈的意见较多。结论跟踪调查表明,GB 7718—2011的整体合理程度较高、可操作性强,但是部分具体条款还需要提高其科学性和实用性。建议要加大对中小生产企业、监管部门的标准培训力度和深度,推进标准的执行。     

Heat release during thermally-induced failure of a lithium ion battery: Impact of cathode composition

A novel experimental technique, Copper Slug Battery Calorimetry (CSBC), was employed for the measurement of the energetics and dynamics of the thermally-induced failure of 18650 form factor lithium ion batteries (LIBs) containing three different cathodes: lithium cobalt oxide (LCO), lithium nickel manganese cobalt oxide (NMC) and lithium iron phosphate (LFP). The heat capacity of these LIBs was evaluated to be 1.1±0.1 J g⁻¹ K⁻¹ for all three types. It was shown that the total heat generated inside the batteries increases with increasing amount of electrical energy stored. The maximum total internal heat generated by fully-charged LIBs was found to be 37.3±3.3, 34.0±1.8 and 13.7±0.4 kJ/cell for LCO, NMC and LFP LIBs, respectively. Detailed modeling of heat transfer in the CSBC experiments was carried out to evaluate thermal conductivities of the LIBs and demonstrate that the assumptions associated with the CSBC experiment analysis are valid. Additionally, experiments were carried out in which the CSBC technique was combined with cone calorimetry to measure the heat produced in flaming non-premixed combustion of vented battery materials. The released combustion heat varied between 35 and 63 kJ/cell for LCO LIBs, 27 and 81 kJ/cell for NMC LIBs, and 36 and 50 kJ/cell for LFP LIBs.     

Immune inspired Fault Detection and Diagnosis: A fuzzy-based approach of the negative selection algorithm and participatory clustering

This paper describes an immune-inspired system based on an alternate theory about the self–nonself distinction theory, which defines the negative selection process as a mechanism of a fuzzy system based on the affinity between antigen and T-cells. This theory may provide a decision making tool which improves the generation of detectors or even define new data monitoring in order to detect an extreme variation of the system behavior, which means anomalies occurrences. Through these algorithms, tests are performed to detect faults of a DC motor. Upon detection of faults, a participatory clustering algorithm is used to classify these faults and tested to obtain the best set of parameters to achieve the most accurate clustering for these tests in the application being discussed in the article.