151 research outputs found
Relativistic k-fields with Massless Soliton Solutions in 3+1 Dimensions
In this work, the relativistic non-standard Lagrangian densities (k-fields)
with massless solutions are generally introduced. Such solutions are not
necessarily energetically stable. However, in 3+1 dimensions, we introduce a
new k-field model that results in a single non-topological massless solitary
wave solution. This special solution is energetically stable; that is, any
arbitrary deformation above its background leads to an increase in the total
energy. In other words, its energy is zero which is the least energy in all
solutions. Hence, it can be called a massless soliton solution
Effects of supplemental microbial phytase enzyme on performance and phytate phosphorus digestibility of a corn-wheat-soybean meal diet in broiler chicks
This experiment was conducted to investigate the effects of supplemental phytase in a corn-wheatsoybean meal basal diet on phosphorus (P) digestibility and performance of broiler chicks. 378 one-day old broiler chicks (Ross 308) were allocated to 3Ă—3 factorial arrangements with three levels of phytase enzyme (0, 500 and 1000 FTU/kg) and three levels of non-phytate P (100, 80 and 60% of NRC requirements). Broiler chicks received experimental diets from 7 to 49 days of age. Phytase significantly (P < 0.05) improved body weight gain and feed intake. Tibial ash and P contents increased significantly by phytase supplementation. Ileal P digestibility increased and P excretion reduced by added phytase. The greatest response due to supplemental phytase regarding P digestibility and utilization was obtained at the lowest dietary non-phytate P (NPP) level (60% of NRC requirements). Difference between various levels of added phytase (500 and 1000 FTU/kg) regarding P excretion and utilization was not significant. The interactions between supplemental phytase and dietary NPP for P utilization, tibial ash and P contents were significant (P < 0.05). The results indicate that, supplemental microbial phytase (500 FTU/kg of diet) added to diet containing NPP lower than NRC requirements (60%) can improve growth performance, tibial ash and phytate P utilization in broiler chickens.Key words: Broiler, phytase, phosphorus digestibility, growth performance, tibia
Performance, immunity, serum biochemical and hematological parameters in broiler chicks fed dietary thyme as alternative for an antibiotic growth promoter
A research study was conducted to investigate the effect of dietary inclusion of thyme powder as an antibiotic growth promoter substitution on performance, immune responses, hematological and biochemical parameters in broiler chicks. In this study, 192 day old chicks (Ross 308) were allocated to four treatments with four replicates based on a completely randomized design. Dietary treatments included control, antibiotic (flavophospholipol), and 5 and 10 g/kg thyme powder. Supplementing the diet with antibiotic and 5 g/kg thyme resulted in a significant increase in body weight (P<0.05). Feed intake of broilers was not markedly influenced by treatments but birds fed diets containing antibiotic had the lowest FCR (P<0.05). None of the immune related parameters tested differed significantly among experimental treatments (P>0.05). Thyme powder at 10 g/kg level significantly (P<0.05) increased HDL-cholesterol concentration but protein, albumin, triglyceride, total and LDL cholesterol concentrations were not influenced. Treatments also failed to induce any statistical impacts on hematological parameters of broilers including red and white blood cell count, hemoglobin and hematocrit values. The obtained results suggest that supplementing broilers’ diet with 5 g/kg thyme can indicate favorable influences of antibiotic growth promoter on performance without any detrimental impacts on immune responses and blood parameters.Key words: Broiler, thyme, growth performance, immunity, serum biochemistry, hematology
Effect of frozen storage on texture and color of fish burgers produced from Sarm surimi
Surimi is a high quality myofibrillar protein concentrate that is obtained from cheap and underutilized fish species. In this research, surimi burger was prepared from Sarm (Scomberiodes commersonnianus) surimi (60%) and other ingredients. Some quality attributes of surimi burger were investigated during 3 months of frozen storage at -20°C. Fat value was determined in fresh raw surimi and surimi burger. Physical properties such as color stability (L, a and b values) and textural hardness before and after cooking were determined for surimi burgers during frozen storage at -20°C. Results showed that the hardness of surimi burgers and cooked samples were 768gf and 204gf, respectively at-the beginning of storage, and it was increased at the end of storage (921gf for surimi burger and 462gf for the cooked sample). Hardness showed significant difference through storage (P0.05)
Bessel beam illumination reduces random and systematic errors in quantitative functional studies using light-sheet microscopy
Light-sheet microscopy (LSM), in combination with intrinsically transparent zebrafish larvae, is a choice method to observe brain function with high frame rates at cellular resolution. Inherently to LSM, however, residual opaque objects cause stripe artifacts, which obscure features of interest and, during functional imaging, modulate fluorescence variations related to neuronal activity. Here, we report how Bessel beams reduce streaking artifacts and produce high-fidelity quantitative data demonstrating a fivefold increase in sensitivity to calcium transients and a 20 fold increase in accuracy in the detection of activity correlations in functional imaging. Furthermore, using principal component analysis, we show that measurements obtained with Bessel beams are clean enough to reveal in one-shot experiments correlations that can not be averaged over trials after stimuli as is the case when studying spontaneous activity. Our results not only demonstrate the contamination of data by systematic and random errors through conventional Gaussian illumination and but,furthermore, quantify the increase in fidelity of such data when using Bessel beams
The Effect of Different Cooking Methods on Lead and Cadmium Contents of Shrimp and Lobster
ABSTRACT: Regular consumption of seafood has been widely recommended by the authorities. However, some species especially benthic crustaceans accumulate heavy metals. In addition, the health risks associated to the consumption of such seafood might increase if the consumers use cooking methods that enhance the concentration of heavy metals. In this study, the effects of different cooking methods (boiling, steaming and frying) on the concentrations of lead (Pb) and cadmium (Cd) in shrimp and lobster were studied. Samples were prepared by wet digestion and the contents of heavy metals were measured by graphite furnace atomic absorption spectrophotometer. Mean concentrations of lead and cadmium for raw samples of shrimp and lobster were 75.67±15.31 and 26.00±8.00 6g/kg and 316.67±66.58 and 195.33±131.46 6g/kg respectively. The findings indicated that the highest contents of lead and cadmium were observed in the fried samples (p<0.05), however the differences were not significant for cadmium. According to the results, boiling and steaming are suggested as the best cooking method to provide healthful seafood
A combined convolutional and recurrent neural network for enhanced glaucoma detection.
Glaucoma, a leading cause of blindness, is a multifaceted disease with several patho-physiological features manifesting in single fundus images (e.g., optic nerve cupping) as well as fundus videos (e.g., vascular pulsatility index). Current convolutional neural networks (CNNs) developed to detect glaucoma are all based on spatial features embedded in an image. We developed a combined CNN and recurrent neural network (RNN) that not only extracts the spatial features in a fundus image but also the temporal features embedded in a fundus video (i.e., sequential images). A total of 1810 fundus images and 295 fundus videos were used to train a CNN and a combined CNN and Long Short-Term Memory RNN. The combined CNN/RNN model reached an average F-measure of 96.2% in separating glaucoma from healthy eyes. In contrast, the base CNN model reached an average F-measure of only 79.2%. This proof-of-concept study demonstrates that extracting spatial and temporal features from fundus videos using a combined CNN and RNN, can markedly enhance the accuracy of glaucoma detection
Additive manufacturing of metal-ceramic metamaterials for RF communications
Additive manufacturing of metal-ceramic metamaterials for RF communication
Analysis of microRNA signatures using size-coded ligation-mediated PCR
The expression pattern and regulatory functions of microRNAs (miRNAs) are intensively investigated in various tissues, cell types and disorders. Differential miRNA expression signatures have been revealed in healthy and unhealthy tissues using high-throughput profiling methods. For further analyses of miRNA signatures in biological samples, we describe here a simple and efficient method to detect multiple miRNAs simultaneously in total RNA. The size-coded ligation-mediated polymerase chain reaction (SL-PCR) method is based on size-coded DNA probe hybridization in solution, followed-by ligation, PCR amplification and gel fractionation. The new method shows quantitative and specific detection of miRNAs. We profiled miRNAs of the let-7 family in a number of organisms, tissues and cell types and the results correspond with their incidence in the genome and reported expression levels. Finally, SL-PCR detected let-7 expression changes in human embryonic stem cells as they differentiate to neuron and also in young and aged mice brain and bone marrow. We conclude that the method can efficiently reveal miRNA signatures in a range of biological samples
- …