Shear properties of metal-free wooden load-bearing walls using plywood jointed with a combination of adhesive tape and wood dowels

In this study, the potential of wood-only (metal-free) load-bearing walls was proposed and tested based on the idea of using the same type of material throughout wherever possible while improving basic properties such as strength, sound insulation, and heat insulation. Specifically, a technique was tested of combining pressure sensitive adhesive tape and wood dowels in place of nails for load-bearing structures with panel reinforcement represented by wood-frame construction. For this paper, its strength was evaluated by conducting in-plane shear tests, which revealed that the initial rigidity and maximum load of the proposed test specimens were greater than that of specimens using nails for jointing. However, the shear load factor, which is calculated based on some strength parameters and which forms the foundation of housing strength design, was slightly lower than that of the nail-jointed specimen. This was because there was a large decline in post-collapse resistance and a lower calculated absorbed energy caused by brittleness. The early detachment of panels was also revealed as a problem in the tests.     

超高效液相-串联四极杆质谱联用法同时测定并比较甘草各部位中8种成分含量

建立同时检测甘草中8种成分:22-羟基-甘草次酸、3-epi-甘草次酸、甘草次酸、甘草酸、甘草苷、芒柄花黄素、异甘草酚、甘草香豆素的超高效液相色谱-串联四极杆质谱联用法。选用胆酸作为三萜成分的内标,相思子素2"-O-β-芹菜糖苷作为酚类化合物的内标。甘草样品经粉碎用甲醇(含内标液)超声提取,采用安捷伦ZORBAX RRHD C18柱(50 mm×2.1 mm,1.8μm),以甲醇-0.1%甲酸溶液为流动相,梯度洗脱,以电喷雾电离源,采用超高效液相-串联四极杆质谱联用动态多反应监测模式测定。结果表明,8种成分检出限均小于0.048 8μg/mL,定量限均小于0.195 2μg/mL,在0.048 8~12.500 0、0.048 8~12.500 0、0.012 2~12.500 0、0.048 8~50.000 0、0.048 8~50.000 0、0.012 2~12.500 0、0.012 2~15.000 0、0.195 2~12.500 0μg/mL范围内,22-羟基-甘草次酸、3-epi-甘草次酸、甘草次酸、甘草酸、甘草苷、芒柄花黄素、异甘草酚、甘草香豆素的峰面积与质量浓度呈良好线性关系,相关系数均大于0.99;方法回收率为97.2%~113.0%间;其日内及日间精密度实验的相对标准偏差分别为2.63%~4.47%及1.75%~3.72%。该方法灵敏度高、稳定性强、操作简便、快捷、准确,可用于甘草各部位及其相关食品质量控制。     

Simultaneous Quantification of Secoisolariciresinol Diglucoside and Cyanogenic Glycosides in Flaxseed Products by Various Processing Methods

Two cyanogenic glycosides (linustatin and neolinustatin) and sucrose were isolated from defatted flaxseed, and their structures were determined by NMR spectral analysis and comparison with existing data. Using secoisolariciresinol diglucoside (SDG) and the cyanogenic glycosides as standards, we developed a method to quantify the three compounds simultaneously by ultrahigh-performance liquid chromatography (UHPLC)-MS in selected reaction monitoring (SRM) mode. Using this tool, flaxseed powder—processed by various methods—was analyzed with regard to the contents of the beneficial compound, SDG, and the toxic compounds, cyanogenic glycosides. The levels of SDG in samples treated with alkaline solution are much higher than in samples without treatment, and in general, the levels of linustatin and neolinustatin in flaxseed powder decreased progressively as heating time is prolonged after treatment with alkaline solutions.     

大豆脂肪氧化酶酶活性变化研究

采用分光光度法对大豆中三种脂肪氧化酶（同工酶）进行检测并测定脂肪氧化酶活性,研究表明：大豆粉碎后随着贮存时间的延长,脂肪氧化酶活性逐渐降低,大豆发芽后脂肪氧化酶活性降低了43%.     

Heat-moisture treatment of high-amylose corn starch increases dietary fiber content and lowers plasma cholesterol in ovariectomized rats

ABSTRACT:  The effect of dietary high-amylose corn starch (HACS) of varying dietary fiber (DF) content on plasma cholesterol was examined in ovariectomized (OVX) rats. Gelatinized normal corn starch (G-CS) was used as a reference. OVX rats were fed a fiber-free purified diet containing G-CS, HACS, gelatinized high-amylose corn starch (G-HACS), or heat-moisture treated HACS (HM-HACS) at 400 g starch/kg diet for 21 d. The DF content of G-CS, HACS, G-HACS, and HM-HACS measured by the AOAC method was 0.1, 19.3, 2.4, and 64.5 g/100 g, respectively. The dry weight of cecal contents, cecal wall weight, the amount of short chain fatty acids in cecal contents, the amount of bile acids in small intestinal contents, and fecal excretion of neutral sterols increased logarithmically with increasing DF, while total plasma cholesterol concentration decreased. On the other hand, hepatic CYP7A1 activity, fecal dry weight, and fecal excretion of bile acids increased linearly with increasing DF, while body weight gain decreased. The hypocholesterolemic effect of HACS in OVX-rats appeared to be more effective by heat-moisture treatment.     

Moisture profiles of wheat noodles containing hydroxypropylated tapioca starch

Wheat noodles were prepared using flour to which hydroxypropylated tapioca starch was added, and the effect of this addition on the moisture distribution within the noodles during cooking was examined using a digital image processing technique. The addition of the modified starch slightly increased the moisture content and narrowed the flat distribution near the noodle surface. The distribution features reflected the changes in the water absorption behaviour caused by the properties of the modified starch and the reduction in the gluten content. Addition of the modified starch lowered Young's modulus and the energy for 99% strain of the noodles in the texture analysis to, at maximum 35% and 65%, and decreased the breakability of the noodles. These changes in the moisture distribution and textural properties have been ascribed to changes in both the state of the starch granules near the surface and the structure of the gluten network.     

Improvement and induction property of radiation-responsive promoter through DNA shuffling of 5′-flanking regions of the human p21 gene

A promoter that augments gene expression in response to stimulation of ionizing radiation would be a desired tool for radiogenetic therapy, a combination of radiotherapy and gene therapy. Although various promoters occurring naturally or artificially have been used for researches, one showing higher reactivity to ionizing radiation is desirable. In the present study, we attempted to improve a radiation-responsive promoter of the p21 through a technique called DNA shuffling. A library of DNA fragments was constructed by re-ligation of randomly digested promoter fragments and improved promoters were chosen out of the library. We repeated this process twice to obtain a promoter showing 2.6-fold better reactivity to ionizing radiation compared with its parent, p21 promoter after 10 Gy γ-ray irradiation. Nucleotide sequence analyses revealed that the obtained promoter was densely packed with some of the cis-acting elements including binding sites for p53, NF-κB, NRF-2, AP-1 and NF-Y more than p21 promoter. In addition, it was shown that its induction by ionizing radiation was dependent upon p53 status of a cell line, suggesting that the promoter retained properties of the p21 promoter. This technique is simple and efficient to improve a promoter responsive to other stimulus of interest besides IR.     

Contrasting diurnal variations in fossil and nonfossil secondary organic aerosol in urban outflow, Japan

Diurnal variations of fossil secondary organic carbon (SOC) and nonfossil SOC were determined for the first time using a combination of several carbonaceous aerosol measurement techniques, including radiocarbon (1?C) determinations by accelerator mass spectrometry, and a receptor model (chemical mass balance, CMB) at a site downwind of Tokyo during the summer of 2007. Fossil SOC showed distinct diurnal variation with a maximum during daytime, whereas diurnal variation of nonfossil SOC was relatively small. This behavior was reproduced by a chemical transport model (CTM). However, the CTM underestimated the concentration of anthropogenic secondary organic aerosol (ASOA) by a factor of 4-7, suggesting that ASOA enhancement during daytime is not explained by production from volatile organic compounds that are traditionally considered major ASOA precursors. This result suggests that unidentified semivolatile organic compounds or multiphase chemistry may contribute largely to ASOA production. As our knowledge of production pathways of secondary organic aerosol (SOA) is still limited, diurnal variations of fossil and nonfossil SOC in our estimate give an important experimental constraint for future development of SOA models.