Roof Collapse, Magic Mart Store, Bolivar, Tennessee

This paper summarizes an investigation of the July 2, 1983, roof collapse of the Magic Mart store in Bolivar, Tennessee. The building was a onestory retail store of steel‐framed roof construction. The collapse occurred during a severe thunderstorm with intense rainfall. The investigation includes review of background information and eyewitness accounts of the collapse, review of design and construction documents, site investigation and sample collection, laboratory testing of samples of the collapse debris, and structural analyses. The initiating mode of failure was instability of one of the beam‐column connections of the roof framing, triggered by ponded roof water. The principal cause of the failure was inadequate buckling resistance of the unbraced and unstiffened beam‐column connections, due to major deviations in the construction from the design documents. Also contributing to the failure were ponding rain water caused by improper slope and drainage of the roof and the increased weight of roofing materials added during the 10‐year life of the building. The paper concludes with a summary of the results of a personal injury law suit resulting from the collapse, and with recommendations for improvement in design and construction practices based on the lessons learned from this failure.     

Short communication: Absorption of 2-hydroxy-4-methylthiobutanoate in dairy cows

The objective of this study was to measure net portal absorption of 2-hydroxy-4-methylthiobutanoate (HMTBA) in dairy cows. Four multicatheterized lactating cows were used in a cross-over design with 7-d experimental periods. They were fed every other hour a total mixed ration and received, in addition, twice a day, 12.5 or 25 g/meal of HMTBA. On the last day of treatment, net portal absorption of HMTBA was numerically greater after the 25-g compared with the 12.5-g bolus meal of HMTBA, and the amount absorbed relative to the dose ingested was unchanged between treatments averaging 11.2 ± 4.7% of the dose. This represents a minimum value of HMTBA availability because it does not take into account any HMTBA metabolized to Met by gut tissues (in sheep this amounted to another 5% of the dose). A rapid method to estimate net portal absorption based on temporal variations of the peripheral plasma HMTBA concentrations following the HMTBA meal is also presented. Based on the good relationship (concordance correlation coefficient = 0.97) observed between direct measurements and estimations, this simplified approach offers a reasonable approach to assess HMTBA absorption under different feeding situations.     

彩色阶调印刷网版及Capillex CP毛细感光膜片

在过去几年中，采用UV油墨网印高质量的四色印刷品取得了巨大进展。此后有关溶剂基油墨释放VOC的环境法规一直在加强，同时印刷用户对多色印刷机的快速干燥以及对彩色图像印刷的需求也在不断增长。然而像生活中的大多数情况一样，没有一样东西是绝对完美的。尽管UV油墨给印刷厂     

Effect of calcium chloride on mechanical properties and microbiological characteristics of cv. Conservolea naturally black olives fermented at different sodium chloride levels

The effect of calcium chloride (CaCl₂)(5 gL^?1) and sodium chloride (NaCl) concentration (40, 60 and 8 gL^?1) on the microbiological and mechanical properties of naturally black olives of cv. Conservolea in brines was studied. In 40 and 60 g L^?1 brines the growth of lactic acid bacteria was favoured over that of yeasts, resulting in rather complete lactic acid fermentation as indicated by high free acidity (9.8–11.5 g lactic acid L^?1) and low pH (3.7–3.8). At 80 g L^?1 brine, yeasts were the dominant members of the microflora, rendering a product with lower acidity (8 g lactic acid L^?1) and higher pH (4.3–4.5). In the presence of CaCl₂ there was a consistent increase in the depth of the peripheral region in which cell wall breakage occurred. When cells separated, perforated walls were observed at sites associated with plasmodesmata. The flesh was strongest and stiffest when CaCl₂ was added to olives treated with 40 g L^?1 brine, consistent with cell wall breakage being the predominant mode of failure. The only observed effect on the mechanical properties of the skin was a stiffening at 60 g L^?1 brine on addition of CaCl₂. Copyright © 2007 Society of Chemical Industry     

Punch-through protection of SSDs in beam accidents

We have tested the effectiveness of punch-through protection (PTP) structures on n-on-p AC-coupled Silicon strip detectors using pulses from an 1064 nm IR laser, which simulate beam accidents. The voltages on the strips are measured as a function of the bias voltage and compared with the results of DC I-V measurements, which are commonly used to characterize the PTP structures. We find that the PTP structures are only effective at very large currents (several mA), and clamp the strips to much larger voltages than assumed from the DC measurements. We also find that the finite resistance of the strip implant compromises the effectiveness of the PTP structures.     

Attrition of porous glass particles in a fluidised bed

Fluidisation is frequently accompanied by unwanted attrition of the bed material. This paper focuses on the mechanical aspects of fines creation by attrition in fluidised beds supported by multi-orifice distributor plates. The attrition rates of low-density porous glass particles were measured; these particles show abrasive wear behaviour rather than breakage. Positron emission particle tracking (PEPT) was used to follow particle motion in three dimensions within the fluidised bed. For a single orifice distributor with background fluidisation, the attrition rate increased exponentially with increasing orifice gas velocity. For a multi-orifice distributor, however, attrition rates were roughly proportional to excess gas velocity, except near to a critical ratio of particle to orifice diameter; as this ratio approached 2, attrition was observed to increase by an order of magnitude. A method is proposed for estimating attrition rates from a combination of small-scale experimental results and theoretical calculations of distributor jet entrainment rates.     

Low pH enhances the transfer of carotene from carrot juice to olive oil

A current model for carotenoid transport and absorption in the gut proposes an initial solubilization in the oil phase of dietary emulsions followed by incorporation of the carotenoids in mixed bile salt micelles. To assess the relevance of the first stage of this model to what is observed in vivo we have examined the transfer of carotene from carrot juice to olive oil. Increased acidity enhanced the transfer from both whole juice and carotene crystals isolated from both whole juice and carotene crystals isolated from carrot chromoplasts. The transfer was significantly slower from whole juice. By using exogenous β-carotene and measuring its transfer to oil in the presence and absence of carrot juice we have demonstrated that the inhibition of the transfer in juice arises, at least in part, from soluble juice factors. The inhibition is relieved by a fall in pH, which leads to lowering of the electric potential at the oil/aqueous phase interface and aggregation of carrot tissue including crystalline carotene. Under conditions of low pH, oil droplets adhere to the tissue aggregates, allowing carotene to pass into the oil. Our results provide an explanation for why carotene absorption in vivo is depressed by conditions of low gastric acidity.     

Calculating thermal radiation hazards in large fires

The author has developed, and discusses here, a method for assessing the thermal radiation hazards to objects from fires. A comparison of the calculations to an actual fire experience seems to indicate that the method is reasonably accurate, though somewhat conservative.     

A Guide to Selecting and Implementing Security Controls

ABSTRACT

The purpose of this article is to inform and educate the Information Security (IS) professional about some of the key/fundamental tenets of Sarbanes-Oxley (SOX), especially in the context of Confidentiality, Integrity and Availability of information, the three cornerstones of every security initiative. The focus is on such Sections of the Act as 404 (Internal Controls), 302 (Management Certifications), 806 (Whistleblower Protections), 409 (Real Time Disclosures), 802 (Alteration of Documents), amongst others. The purpose is to develop an appreciation and understanding of IS requirements and implications of SOX, and likewise to better understand how SOX can provide a basic roadmap for IS that every professional, department and organization may be able to use.