Effect of mash maceration and ripening stage of apples on phenolic compounds and antioxidant power of cloudy juices: A study using chemometrics

The effects of different enzymatic preparations on total phenolic content, phenolic profile (HPLC), and ferric reducing antioxidant power (FRAP) of cloudy juices from Lis Gala and Fuji Suprema apples varieties, at three ripening stages (unripe, ripe and senescent) were investigated using Principal Component Analysis and Hierarchical Cluster Analysis. The commercial preparations enzymatic (Ultrazym^® AFPL; Pectinex^® Ultra Clear; Pectinex^® SMASH XXL; Panzym^® YieldMASH) increased the total phenolic compounds and ferric reducing capacity of the cloudy juice from unripe and ripe Lis Gala (respectively by 67 and 49% for unripe apples, and 28 and 33% for ripe apples) and unripe Fuji Suprema apples (23 and 55%), while for the ripe Fuji Suprema apples only Pectinex^® Ultra Clear and Panzym^® YieldMASH had this effect. No significant (p > 0.05) was observed on senescent stage, whatever the enzymatic preparation. Enzymatic preparations could increase phenolic compounds concentration and antioxidant capacity of cloudy apple juice, but this effect depended on the maturity of the apples.     

Effect of internal curing by using superabsorbent polymers (SAP) on autogenous shrinkage and other properties of a high-performance fine-grained concrete: results of a RILEM round-robin test

The article presents the results of a round-robin test performed by 13 international research groups (representing fifteen institutions) in the framework of the activities of the RILEM Technical Committee 225-SAP “Applications of Superabsorbent Polymers in Concrete Construction”. Two commercially available SAP materials were used for internal curing of a high-performance, fine-grained concrete in combination with the addition of extra water. The concrete had the same mix composition in all laboratories involved but was composed of local materials. All found a considerable decrease in autogenous shrinkage attributable to internal curing. Also, with regard to the shrinkage-mitigating effect of both particular SAP materials, the results were consistent. This demonstrates that internal curing using SAP is a robust approach, working independently of some variations in the concretes’ raw materials, production process, or measuring technique. Furthermore, the effects of internal curing on other properties of concrete in its fresh and hardened states were investigated. These are consistent as well and expand considerably the existing data basis on properties of concrete materials containing SAP.     

Strain and thermal expansion coefficients of various cement pastes during hydration at early ages

Cement pastes undergo elevated temperature histories due to hydration heat liberation at early ages. Thermal expansion coefficients of cement paste and concrete change with age, showing a decrease after mixing, a subsequent minimum and then a gradual increase. These changes contribute to thermal strain. In this study, effects of water–cement ratio and cement type on volume changes in early-age cement pastes were experimentally examined using a newly developed apparatus capable of simultaneously determining both thermal expansion coefficient and total strain of cement pastes. The dependence of the thermal expansion coefficient on hydration was affected by water–cement ratio, cement type, elevated temperature history and particularly by the free water content of the cement pastes, while the relationship between thermal expansion coefficient and free water content varied with water–cement ratio. A notable increase in thermal expansion coefficient at early ages was observed when water–cement ratio was low and alite content in cement was high. At a water–cement ratio of 0.30, low-heat Portland cement paste resulted in a small total strain while moderate-heat and ordinary Portland cement pastes showed larger strains. Because no particular difference was observed in the thermal strains, shrinkage in the low-heat Portland cement paste was attributed to autogenous strain. At a water–cement ratio of 0.40, self-desiccation had a significant influence upon autogenous shrinkage and dependence of thermal expansion coefficient on hydration, and the effect of the mineral composition of cements was notable. However, for cement pastes with a water cement ratio of 0.55, no significant effects of self-desiccation were observed, probably because considerable excess water was present.     

Commissioning and performance of the variable line spacing plane grating monochromator beamline at the Canadian Light Source

The variable line spacing plane grating monochromator beamline at the Canadian Light Source (CLS) employs three grazing incidence variable line spacing gratings to cover a photon energy range of 5-250 eV. It uses a 185 mm period length planar permanent magnet insertion device as the photon source, sharing a straight section with another soft x-ray beamline at the CLS. The commissioning and performance of the beamline is reported. The high resolution photoabsorption spectra of Ar and PF(5) gases are reported. A resolving power of over 40,000 for photons in the low energy region and >10,000 for a wider energy range (8-200 eV) can be achieved. A photon flux of up to 2 x 10(12) photons/s per 100 mA with slit settings of 50 microm has been measured.     

A cryostat and temperature control system optimized for measuring relaxations of glass-forming liquids

An experimental setup, including a cryostat and a temperature control system, has been constructed to meet the demands of measuring linear and nonlinear macroscopic relaxation properties of glass-forming liquids in the extremely viscous state approaching the glass transition. In order to be able to measure such frequency-dependent response functions accurately (including dielectric permittivity, specific heat, thermal expansivity, and shear and bulk moduli), as well as nonlinear relaxations following a temperature jump, one must have the ability to hold temperatures of liquids steady over the span of several days or even several weeks. To maximize temperature stability, special care is taken to thermally isolate the sample chamber of the cryostat. The main temperature control system is capable of maintaining temperatures within a few millikelvins. If liquid is deposited into a special transducer assembly that includes a subcryostat unit, the temperature of liquids can be maintained even more precisely, within a few tenths of a millikelvin. This subcryostat unit is more responsive to temperature changes because (i) it is equipped with a Peltier element that provides secondary heating and cooling, (ii) the transducer contains a layer of liquid that is only 50 micfom thick, and (iii) feedback proportional-integral-derivative temperature control is implemented by a fully analog circuit. The subcryostat permits us to change and stabilize temperatures quickly; it takes only 10 s to stabilize the temperature within tenths of a millikelvin after a jump of 1 K, for example, a capability that is highly advantageous for accurately observing relaxation processes following a temperature step.     

Automated Verification of Functional Correctness of Race-Free GPU Programs

We study an automated verification method for functional correctness of parallel programs running on graphics processing units (GPUs). Our method is based on Kojima and Igarashi’s Hoare logic for GPU programs. Our algorithm generates verification conditions (VCs) from a program annotated by specifications and loop invariants, and passes them to off-the-shelf SMT solvers. It is often impossible, however, to solve naively generated VCs in reasonable time. A main difficulty stems from quantifiers over threads due to the parallel nature of GPU programs. To overcome this difficulty, we additionally apply several transformations to simplify VCs before calling SMT solvers. Our implementation successfully verifies correctness of several GPU programs, including matrix multiplication optimized by using shared memory. In contrast to many existing verification tools for GPU programs, our verifier succeeds in verifying fully parameterized programs: parameters such as the number of threads and the sizes of matrices are all symbolic. We empirically confirm that our simplification heuristics is highly effective for improving efficiency of the verification procedure.     

Protective effects of chlorogenic acid on paraquat-induced oxidative stress in rats

The protective effects of chlorogenic acid on paraquat-induced oxidative stress were examined in rats. The activities of erythrocytes and liver glutathione peroxidase, and of both liver catalase and glutathione reductase, which were increased by feeding paraquat, declined to the levels in the control rats by supplementing chlorogenic acid to the paraquat diet. The activity of superoxide dismutase was not changed by dietary paraquat or by supplementing chlorogenic acid to the paraquat diet. Paraquat in the diet markedly decreased the liver triacylglycerol and phospholipid concentrations, as well as the food intake and body weight gain, while chlorogenic acid protected against these decreases. These in vivo results and the in vitro superoxide anion scavenging activity of chlorogenic acid suggest that chlorogenic acid acted preventively against paraquat-induced oxidative stress.     

Fas antigen expression and apoptosis of lymphocytes in macaques infected with simian immunodeficiency virus strain mac

The surface of early Earth was exposed to both UVC radiation (< 280 nm) and higher doses of UVB (280-315 nm) compared with the surface of present day Earth. The degree to which this radiation environment acted as a selection pressure on organisms and biological systems has rarely been theoretically examined with respect to the biologically effective irradiances that ancient organisms would receive. Here action spectra for DNA inactivation and isolated chloroplast inhibition are used to estimate biologically effective irradiances on archean Earth. Comparisons are made with present day Earth. The theoretical estimations on the UV radiation screening required to protect DNA on archean Earth compare well with field and laboratory observations on protection strategies found in present day microbial communities. They suggest that many physical and biological methods may have been effective and would have allowed for the radiation of life even under the high UV radiation regimes of archean Earth. Such strategies would also have provided effective reduction of photoinhibition by UV radiation. The data also suggest that the UV regime on the surface of Mars is not a life limiting factor per se, although other environmental factors such as desiccation and low temperatures may contribute towards the apparent lack of a surface biota.     

Cre-loxP-mediated DNA flip-flop in mammalian cells leading to alternate expression of retrovirally transduced genes

Cultured mesangial cells constitutively express alpha-smooth muscle actin (alpha-SMA), a marker of cellular activation. We unexpectedly found that tyrosine kinase pp60v-src, a known activator for a wide range of signalling cascades, suppressed the alpha-SMA expression in mesangial cells. The present study was conducted to elucidate molecular events involved in this phenomenon. Transfection with a reporter plasmid revealed that the serum response element (SRE), the cis-element required for alpha-SMA expression, was constitutively active in mesangial cells. When mesangial cells were transfected with pp60v-src, activity of both SRE and the alpha-SMA promoter was down-regulated. This was associated with depressed levels of phosphorylated extracellular signal-regulated kinases (ERKs), but not c-Jun N-terminal kinase. Selective inhibition of ERKs by PD098059 abrogated constitutive SRE activity, leading to suppressed alpha-SMA expression. These results uncovered a novel potential of pp60v-src for suppression of alpha-SMA via intervention in the ERK-SRE signalling pathway.     

Autoimmune enteropathy with severe atrophic gastritis and colitis in an adult: proposal of a generalized autoimmune disorder of the alimentary tract

BACKGROUND: We describe the case of an adult with autoimmune enteropathy consistent with both severe atrophic gastritis accompanying antral stenosis and colitis. METHODS AND RESULTS: The patient, positive for anti-intrinsic factor antibody, had intractable diarrhea and protein-losing enteropathy. In the ileum inflammatory cells were observed infiltrating the lamina propria along with villus atrophy, and similar inflammation was also found in the lamina propria of the colon and stomach, with complete loss of specialized glands. The myenteric ganglion cells of the hypertrophied muscularis propria in the stenosed antrum showed degeneration with surrounding T-lymphocyte infiltration. There were more CD8+ than CD4 lymphocytes in the lamina propria of the stomach and colon. CONCLUSIONS: The CD8+ (suppressor-cytotoxic) T lymphocytes may have played an important role in the production of lesions in the stomach, small intestine, and colon, so we propose this case as an example of a generalized autoimmune disorder of the alimentary tract.