Effect of the Gamma Radiation Dose Rate on Psychrotrophic Bacteria, Thiobarbituric Acid Reactive Substances, and Sensory Characteristics of Mechanically Deboned Chicken Meat

Frozen samples of mechanically deboned chicken meat (MDCM) with skin were irradiated with gamma radiation doses of 0.0 kGy (control) and 3 kGy at 2 different radiation dose rates: 0.32 kGy/h (3 kGy) and 4.04 kGy/h (3 kGy). Batches of irradiated and control samples were evaluated during 11 d of refrigerated (2 +/- 1 degrees C) storage for the following parameters: total psychrotrophic bacteria count, thiobarbituric acid reactive substances (TBARS), evaluation of objective color (L*, a*, and b*) and a sensory evaluation (irradiated odor, oxidized odor, pink and brown colors). No statistical difference (P > 0.05) was found amongst the TBARS values obtained for the MDCM samples irradiated with dose rates of 0.32 and 4.04 kGy/h. There was a significant increase (P < 0.05) in the psychrotrophic bacterial count as from the 7th day of refrigerated storage, for the MDCM samples irradiated at the dose rate of 4.04 kGy/h. With respect to the attribute of oxidized odor, the samples irradiated with a dose rate of 0.32 kGy/h showed a stronger intensity and were significantly different (P < 0.05) from the sample irradiated with a dose rate of 4.04 kGy/h on days 0 and 2 of refrigerated storage. Irradiation with a dose rate of 4.04 kGy/h (3 kGy) was shown to be the best condition for the processing of MDCM according to the evaluation of all the variables, under the conditions of this study. Practical Application The results obtained for the application of different dose rates of ionizing radiation to mechanically deboned chicken meat will provide the food industry with information concerning the definition of the best processing conditions to maximize the sensory and food quality.

A new polymorphism in the Growth and Differentiation Factor 9 (GDF9) gene is associated with increased ovulation rate and prolificacy in homozygous sheep

P>Brazilian Santa Ines (SI) sheep are very well-adapted to the tropical conditions of Brazil and are an important source of animal protein. A high rate of twin births was reported in some SI flocks. Growth and Differentiation Factor 9 (GDF9) and Bone Morphogenetic Protein 15 (BMP15) are the first two genes expressed by the oocyte to be associated with an increased ovulation rate in sheep. All GDF9 and BMP15 variants characterized, until now, present the same phenotype: the heterozygote ewes have an increased ovulation rate and the mutated homozygotes are sterile. In this study, we have found a new allele of GDF9, named FecGE (Embrapa), which leads to a substitution of a phenylalanine with a cysteine in a conservative position of the mature peptide. Homozygote ewes presenting the FecGE allele have shown an increase in their ovulation rate (82%) and prolificacy (58%). This new phenotype can be very useful in better understanding the genetic control of follicular development; the mechanisms involved in the control of ovulation rate in mammals; and for the improvement of sheep production.

MODIS NDVI time-series allow the monitoring of Eucalyptus plantation biomass

The use of remote sensing is necessary for monitoring forest carbon stocks at large scales. Optical remote sensing, although not the most suitable technique for the direct estimation of stand biomass, offers the advantage of providing large temporal and spatial datasets. In particular, information on canopy structure is encompassed in stand reflectance time series. This study focused on the example of Eucalyptus forest plantations, which have recently attracted much attention as a result of their high expansion rate in many tropical countries. Stand scale time-series of Normalized Difference Vegetation Index (NDVI) were obtained from MODIS satellite data after a procedure involving un-mixing and interpolation, on about 15,000 ha of plantations in southern Brazil. The comparison of the planting date of the current rotation (and therefore the age of the stands) estimated from these time series with real values provided by the company showed that the root mean square error was 35.5 days. Age alone explained more than 82% of stand wood volume variability and 87% of stand dominant height variability. Age variables were combined with other variables derived from the NDVI time series and simple bioclimatic data by means of linear (Stepwise) or nonlinear (Random Forest) regressions. The nonlinear regressions gave r-square values of 0.90 for volume and 0.92 for dominant height, and an accuracy of about 25 m(3)/ha for volume (15% of the volume average value) and about 1.6 m for dominant height (8% of the height average value). The improvement including NDVI and bioclimatic data comes from the fact that the cumulative NDVI since planting date integrates the interannual variability of leaf area index (LAI), light interception by the foliage and growth due for example to variations of seasonal water stress. The accuracy of biomass and height predictions was strongly improved by using the NDVI integrated over the two first years after planting, which are critical for stand establishment. These results open perspectives for cost-effective monitoring of biomass at large scales in intensively-managed plantation forests. (C) 2011 Elsevier Inc. All rights reserved.

Outcrossing rate in sweet passion fruit based on molecular markers

P>Yellow and sweet passion fruit are insect-pollinated species native to the tropics. Fruits are used commercially for human consumption worldwide. The yellow passion fruit is an outcrossing species with self-incompatible flowers. However, the reproductive system of the sweet passion fruit (Passiflora alata) has not been well elucidated. The objective of this work was to characterize aspects of the mating system in the sweet passion fruit using random amplified polymorphic DNA (RAPD) and microsatellite markers, particularly the rate of outcrossing in P. alata progenies. A multilocus outcrossing rate of t(m) = 0.994 was determined from RAPD and t(m) = 0.940 from microsatellites, supporting P. alata as an outcrossing species. The fixation indices of the maternal generation (F(m)) were -0.200 and 0.071 with RAPD and microsatellite loci, respectively, indicating the absence of inbreeding in the maternal generation. The paternity correlation (r(p)) varied from -0.008 with RAPD markers to 0.208 with microsatellite markers, suggesting a low probability of finding full sibs within the progenies. The results demonstrated that all progenies assessed in this study were derived from outcrossing.

Test procedure for variable rate fertilizer on coffee

The objective was to develop and test a procedure for applying variable rates of fertilizers and evaluate yield response in coffee (Coffea arabica L.) with regard to the application of phosphorus and potassium. The work was conducted during the 2004 season in a 6.4 ha field located in central Sao Paulo state. Two treatments were applied with alternating strips of fixed and variable rates during the whole season: one following the fertilizing procedures recommended locally, and the other based on a grid soil sampling. A prototype pneumatic fertilizer applicator was used, carrying two conveyor belts, one for each row. Harvesting was done with a commercial harvester equipped with a customized volumetric yield monitor, separating the two treatments. Data were analyzed based on geostatistics, correlations and regressions. The procedure showed to be feasible and effective. The area that received fertilizer applications at a variable rate showed a 34% yield increase compared to the area that received a fixed rate. The variable rate fertilizer resulted in a savings of 23% in phosphate fertilizer and a 13% increase in potassium fertilizer, when compared to fixed rate fertilizer. Yield in 2005, the year after the variable rate treatments, still presented residual effect from treatments carried out during the previous cycle.

Influence of storage temperature on cooling intensity of topical emulsions containing encapsulated menthol

The cooling intensity of topical emulsions added with encapsulated or free menthol was evaluated by a screened and trained panel recruited based on the American Society for Testing and Materials method. A sensory panel composed of 10 trained judges performed the evaluation of samples stored at 22 +/- 2C for 24 h and, after 28 days of storage, at 37.0 +/- 0.5C. The obtained data were analyzed by analysis of variance and Tukey`s test. The results showed an increase of cooling intensity as a function of encapsulated menthol concentration. The opposite was observed in samples added with free menthol, which may have caused sensory fatigue. Storage at 37 +/- 0.5C for 28 days had no impact on the cooling intensity of emulsions containing encapsulated menthol, demonstrating high stability and suggesting its application in cooling skin care products. In contrast, emulsions added with free menthol showed a drastic decrease of cooling intensity at 37 +/- 0.5C..

Effects of light intensity and dilution rate on the semicontinuous cultivation of Arthrospira (Spirulina) platensis. A kinetic Monod-type approach

Semicontinuous cultures were carried out at different dilution rates (D) and light intensities (I) to determine the maximum productivity of Arthrospira platensis cultivated in helicoidal photobioreactor up to the achievement of pseudo-steady-state conditions. At I = 108 mu mol photons m(-2) s(-1), the semicontinuous regime ensured the highest values of maximum cell concentration (X(m) = 5772 +/- 113 mg L(-1)) and productivity (P(XS) = 1319 +/- 25 mg L(-1) d(-1)) at the lowest (D = 0.1 day(-1)) and the highest (D = 0.3 day(-1)) dilution rates, respectively. A kinetic model derived from that of Monod was proposed to determine the relationship between the product of light intensity to dilution rate (ID) and the cell productivity, which were shown to exert a combined influence on this parameter. This result put into evidence that pseudosteady-state conditions could be modified according to circumstances, conveniently varying one or other of the two independent variables. (C) 2010 Elsevier Ltd. All rights reserved.

Effects of carbon dioxide feeding rate and light intensity on the fed-batch pulse-feeding cultivation of Spirulina platensis in helical photobioreactor

The behavior of S. platensis was investigated in this study through fed-batch pulse-feeding cultures performed at different carbon dioxide feeding rates (F = 0.44-1.03 g L-1 d(-1)) and photosynthetic photon flux density (PPFD = 80-250 mu mol photons m(-2) s(-1)) in a bench-scale helical photobioreactor. To achieve this purpose, an inorganic medium lacking the carbon source was enriched by gaseous carbon dioxide from a cylinder. The maximum cell concentration achieved was 12.8 g L-1 at PPFD = 166 mu mol photons m(-2) s(-1) and F= 0.44 g L-1 d(-1) of CO2. At PPFD = 80 and 125 mu mol photons m(-2) s(-1), the carbon utilization efficiency (CUE) reached maximum values of 50 and 69%, respectively, after about 20 days, and then it decreased, thus highlighting a photolimitation effect. At PPFD = 166 mu mol photons m(-2) s(-1), CUE was >= 90% between 20 and 50 days. The photosynthetic efficiency reached its maximum value (9.4%) at PPFD = 125 mu mol photons m(-2) s(-1). The photoinhibition threshold appeared to strongly depend on the feeding rate: at high PPFD, an increase in the amount of fed CO2 delayed the inhibitory effect on biomass growth, whereas at low PPFD, excess CO2 addition caused the microalga to stop growing. (c) 2007 Elsevier B.V. All rights reserved.

UV-Derivative Spectrophotometric and Stability-Indicating High-Performance Liquid Chromatographic Methods for Determination of Simvastatin in Tablets

A stability-indicating high-performance liquid chromatographic (HPLC) and a second-order derivative spectrophotometric (UVDS) analytical methods were validated and compared for determination of simvastatin in tablets. The HPLC method was performed with isocratic elution using a C18 column and a mobile phase composed of methanol:acetonitrile:water (60:20:20, v/v/v) at a flow rate of 1.0 ml/min. The detection was made at 239 nm. In UVDS method, methanol and water were used in first dilution and distilled water was used in consecutive dilutions and as background. The second-order derivative signal measurement was taken at 255 nm. Analytical curves showed correlation coefficients > 0.999 for both methods. The quantitation limits (QL) were 2.41 mu g/ml for HPLC and 0.45 mu g/ml for UVDS, respectively. Intra and inter-day relative standard deviations were < 2.0 %. Statistical analysis with t- and F-tests are not exceeding their critical values demonstrating that there is no significant difference between the two methods at 95 % confidence level.

BLOCKING CENTRAL LEUKOTRIENES SYNTHESIS AFFECTS VASOPRESSIN RELEASE DURING SEPSIS

Recent studies revealed that vasopressinergic neurons have a high content of cys-leukotriene C(4) (LTC(4)) synthase, a critical enzyme in cys-leukotriene synthesis that may play a role in regulating vasopressin secretion. This study investigates the role of this enzyme in arginine vasopressin (AVP) release during experimentally induced sepsis. Male Wistar rats received an i.c.v. injection of 3-[1-(p-chlorobenzyl)-5-(isopropyl)-3-tert-butylthioindol-2-yl]-2, 2-dimethylpropanoic acid (MK-886) (1.0 mu g/kg), a leukotrienes (LTs) synthesis inhibitor, or vehicle, 1 h before cecal ligation and puncture (CLP) or sham operation. In one group of animals the survival rate was monitored for 3 days. In another group, the animals were decapitated at 0, 4, 6, 18 and 24 h after CLP or sham operation, and blood was collected for hematocrit, serum sodium and nitrate, plasma osmolality, protein and AVP determination. A third group was used for blood pressure measurements. The neurohypophysis was removed for quantification of AVP content, and the hypothalamus was dissected for LTC4 synthase analysis by Western blot. Mortality after CLP was reduced by the central administration of MK-886. The increase in plasma AVP levels and hypothalamus LTC4 synthase content in the initial phase of sepsis was blocked, whereas the decrease in neurohypophyseal AVP content was partially reversed. Also the blood pressure drop was abolished in this phase. The increase of serum nitric oxide and hematocrit was reduced, and the decrease in plasma protein and osmolality was not affected by the LTs blocker. In the final phase of sepsis, the plasma AVID level and the hypothalamic LTC4 synthase content were at basal levels. The central administration of MK-886 increased the hypothalamic LTC4 synthase content but did not alter the plasma and neurohypophysis AVID levels observed, or the blood pressure during this phase. These results suggest that the central LTs are involved in the vasopressin release observed during sepsis. (C) 2009 IBRO. Published by Elsevier Ltd. All rights reserved.

Real exchange rate and elasticity of labour supply in a balance-of-payments-constrained macrodynamics

A macrodynamic model is proposed in which the real exchange rate and the elasticity of labour supply interact defining different trajectories of growth and income distribution in a developing economy. Growth depends on imports of capital goods which are paid with exports (there are no capital flows) and hence is constrained by equilibrium in current account. The role of the elasticity of labour supply is to prevent the real exchange rate from appreciating as the economy grows, thereby sustaining international competitiveness. The model allows for endogenous technological change and considers the impact of migration from the subsistence to the modern sector on the cumulative (Kaldor-Verdoorn) process of learning.

Revisiting the interest rate puzzle

This article makes a connection between Lucas` (1978) asset pricing model and the macroeconomic dynamics for some selected countries. Both the relative risk aversion and the impatience for postponing consumption by synthesizing the investor behaviour can help to understand some key macroeconomic issues across countries, such as the savings decision and the real interest rate. I find that the government consumption makes worse the so-called `equity premium-interest rate puzzle`. The first root of the quadratic function for explaining the real interest rate can produce this puzzle, but not the second root. Thus, Mehra and Prescott (1985) identified only one possible solution.

Interaction of 10-(octyloxy) decyl-2-(trimethylammonium) ethyl phosphate with mimetic membranes and cytotoxic effect on leukemic cells

10-(Octyloxy) decyl-2-(trimethylammonium) ethyl phosphate (ODPC) is an alkylphospholipid that can interact with cell membranes because of its amphiphilic character. We describe here the interaction of ODPC with liposomes and its toxicity to leukemic cells with an ED-50 of 5.4, 5.6 and 2.9 pM for 72 h of treatment for inhibition of proliferation of NB4, U937 and K562 cell lines, respectively, and lack of toxicity to normal hematopoietic progenitor cells at concentrations up to 25 pM. The ED-50 for the non-malignant HEK-293 and primary human umbilical vein endothelial cells (HUVEC) was 63.4 and 60.7 mu M, respectively. The critical micellar concentration (CMC) of ODPC was 200 mu M. Dynamic light scattering indicated that dipalmitoylphosphatidylcholine (DPPC) liposome size was affected only above the CMC of ODPC. Differential calorimetric scanning (DCS) of liposomes indicated a critical transition temperature (T(c)) of 41.5 degrees C and an enthalpy (Delta H) variation of 7.3 kcal mol(-1). The presence of 25 mu M ODPC decreased T(c) and Delta H to 393 degrees C and 4.7 kcal mol(-1), respectively. ODPC at 250 mu M destabilized the liposomes (36.3 degrees C. 0.46 kcal mol(-1)). Kinetics of 5(6)-carboxyfluorescein (CF) leakage from different liposome systems indicated that the rate and extent of CF release depended on liposome composition and ODPC concentration and that above the CMC it was instantaneous. Overall, the data indicate that ODPC acts on in vitro membrane systems and leukemia cell lines at concentrations below its CMC, suggesting that it does not act as a detergent and that this effect is dependent on membrane composition. (C) 2010 Elsevier B.V. All rights reserved.

Coronary Calcification Is Associated With Lower Bone Formation Rate in CKD Patients Not Yet in Dialysis Treatment

Vascular calcification is a strong prognostic marker of mortality in hemodialysis patients and has been associated with bone metabolism disorders in this population. In earlier stages of chronic kidney disease (CKD), vascular calcification also has been documented. This study evaluated the association between coronary artery calcification (CAC) and bone histomorphometric parameters in CKD predialysis patients assessed by multislice coronary tomography and by undecalcified bone biopsy. CAC was detected in 33 (66%) patients, and their median calcium score was 89.7 (0.4-2299.3 AU). The most frequent bone histologic alterations observed included low trabecular bone volume, increased eroded and osteoclast surfaces, and low bone-formation rate (BFR/BS). Multiple logistic regression analysis, adjusted for age, sex, and diabetes, showed that BFR/BS was independently associated with the presence of coronary calcification [p=.009; odd ratio (OR) = 0.15; 95% confidence interval (Cl) 0.036-0.619] This study showed a high prevalence of CAC in asymptomatic predialysis CKD patients. Also, there was an independent association of low bone formation and CAC in this population. In conclusion, our results provide evidence that low bone-formation rate constitutes another nontraditional risk factor for cardiovascular disease in CKD patients. 2010 American Society for Bone and Mineral Research.