On the basic theorems in linear elastostatics for bodies containing edge cracks

We prove the work and energy theorem for an elastic body containing an edge crack. As a consequence, we get the reciprocal theorem and uniqueness for some boundary-value problems. Moreover, we obtain some uniqueness theorems for the displacement boundary-value problem.     

On the principle of minimum potential energy in asymmetric elastostatics

The authors prove that the classical principle of minimum potential energy of linear elastostatics may be stated in the case where the medium is a micropolar elastic body occupying an unbounded region of the space.     

Ultrastructural study of apoptotic U937 [corrected] cells treated with different pro-apoptotic substances

Human monocytic leukemia U937 cells readily undergo apoptosis when exposed to various stimuli, including inhibition of protein synthesis, oxidative stress, antitumoral agents, etc. The sequential, step-by-step morphological changes in U937 cells that occur during the apoptotic program are largely determined by the activation of a specific class of proteases, the caspases. The action of these proteases were followed at the ultrastructural level. From our observations 1) no unique morphological feature exists during apoptosis, even in the same cell type; 2) the extent of the morphological modifications are inducer- and dose-dependent; 3) double or triple treatments amplify the morphological modifications with a single inducer, but not the rate of apoptosis; and 4) in the case of double treatment the second inducer has to have a cytoplasmatic target because damage to the cytoplasm occurs before nuclear modifications become visible. These data should facilitate a more objective evaluation of apoptosis in conditions where antiproliferative drugs, like antiblastic or immunosuppressive molecules, are used to monitor the efficiency of treatment.     

Comparative performance of a UASB reactor and an anaerobic packed-bed reactor when treating potato waste leachate

The results presented in this paper are from studies on a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and an anaerobic packed-bed (APB) reactor treating potato leachate at increasing organic loading rates from 1.5 to 7.0 g COD/1/day. The hydraulic retention times ranged from 13.2 to 2.8 days for both reactors during the 100 days of the experiment. The maximum organic loading rates possible in the laboratory-scale UASB and APB reactors for stable operation were approximately 6.1 and 4.7 g COD/l day, respectively. The COD removal efficiencies of both reactors were greater than 90% based on the total COD of the effluent. The methane yield increased with increasing organic loading rate up to 0.23 l CH₄/g COD_degraded in the UASB reactor and 0.161 CH₄/g COD_degraded in the APB reactor. The UASB could be run at a higher organic loading rate than the APB reactor and achieved a higher methane yield. Signs of reactor instability were decreasing partial alkalinity and pH and increasing amounts of volatile fatty acids. The study demonstrated the suitability of the UASB and a packed-bed reactor for treating leachate from potato waste.     

Comparison of analytical methods for measuring proanthocyanidins in wines and their relationship with perceived astringency

The concentration of proanthocyanidins from twenty red wines from cv. Cabernet Sauvignon, five rosé wines from cv. Cabernet Sauvignon and five white wines from cv. Sauvignon Blanc was quantified using four analytical methodologies, and their relationship with the perceived astringency was investigated. Proanthocyanidin concentrations were determined by a methylcellulose precipitation assay, a protein precipitation assay and two colourimetric methods (Bate‐Smith and vanillin assay). The four methodologies showed high repeatability but differed widely in proanthocyanidin concentrations. The methylcellulose and protein precipitation assays could not quantify proanthocyanidins in rosé and white wines. The protein precipitation assay gave the lowest concentration of proanthocyanidins in all of the red wines. The methylcellulose precipitation assay (r = 0.7725; r² = 0.59) and the protein precipitation assay (r = 0.6828; r² = 0.47) showed a strong correlation with the perceived astringency compared with the colourimetric methods. The strong correlation of the methylcellulose precipitation method with the perceived astringency could be a useful tool to estimate red wine astringency.     

Identification of the Pseudomonas fluorescens group as being responsible for blue pigment on fresh cheese

New cases of blue cheese discoloration has led to recent research to identify the causal agent and factors that favor blue pigment appearing. Nonetheless, very few reports have described the source of contamination and the measurements to eradicate the microbiological source on cheese farms by determining the relation between blue discoloration on fresh cheese and the Pseudomonas fluorescens group. Thus, 60 samples from a cheese farm (cheese, equipment surfaces, tap water, and raw and pasteurized milk) were analyzed by phenotypical, MALDI-TOF, 16S rRNA sequencing and pulsed-field gel electrophoresis tests to determine the causal agent. The results obtained by pulsed-field gel electrophoresis with restriction enzymes XbaI and SpeI confirmed tap water as the initial contaminated source. The above-mentioned result was essential to avoid Pseudomonas contamination due to the most residual microorganisms being inactivated through a new disinfection program.     

选择合适的环境光传感器来优化OLED性能

有机发光二极管有很多优点,诸如固有亮度、低功耗、最小厚度、短响应时间、高对比度、宽可视角和逼真的色彩.毫无疑问,它们将成为手持设备中显示技术的首选.     

On some classical theorems in micropolar elasticity

By means of suitable a priori estimates, some classical theorems for the system of micropolar elasticity are proved in arbitrary domains. No assumptions are made upon the behaviour of solutions at infinity and the coefficients of the equations may suitably grow at large spatial distance.