RSM and ANN approaches for modeling and optimizing of electrospun polyurethane nanofibers morphology

This paper focused on using response surface methodology (RSM) and artificial neural network (ANN) to analyze polyurethane (PU) nanofibers morphology synthesized by electrospinning. The process was characterized in detail by using experimental design to determine the parameters that may affect the nanofibers morphology such as polymer concentration, a tip to collector distance and applied voltage. It was concluded that solution concentration plays an important role (relative importance of 79.85 %) against nanofibers diameter and its standard deviation. Based on the results, applied voltage has a different effect on the nanofiber diameter at low and high solution concentrations. Moreover, the tip to collector distance parameter has no significant impact on the average nanofiber diameter. The finest PU nanofiber (201 nm) was obtained from experimental under conditions of: 9 w/v% polymer concentrations, 12 cm tip to collector distance and 16 kV applied voltage. The results show a very good agreement between the experimental and modeled data. It was demonstrated that both models (specially, in case of neural network) are excellent for predicting diameter of PU nanofibers. Furthermore, numerical optimization has been performed by considering desirability function to access the region in design space that introduces minimum average diameter.     

Fabrication and characterization study of electrospun quantum dot — poly vinyl alcohol composite nanofiber for novel engineering applications

CdTe quantum dot/PVA (poly vinyl alcohol) composite nanofiber was successfully fabricated by eletrospinning process. CdTe quantum dots were uniformly dispersed and stabilized into solid nanofiber structure. Spectrofluorometer analysis revealed whenever Q.D??s enter to the PVA solution, due to the aggregation of Q.D??s red shift happens; however, when blend Q.D-PVA solution changes to nanofiber form via electrospining, this shift phenomenon offsets and original fluorescence properties of Q.D??s does not degraded due to excellent individual dispersion of Q.D in the nanofibers structure. It is also turned out that the proportion of Q.D??s incorporated in the composite solution of electrospining has strong influence on the nanofiber morphology. Addition of Q.D??s to PVA solution causes remarkable changes in the conductivity and solution viscosity, therefore different nanofiber morphologies can be obtained as evidenced by scanning electron microscopy. Furthermore, differential scanning calorimetric (DSC) revealed addition of small amount of Q.D??s to the electrospining solution causes strenuous improvement in crystalinity and heat of nanofiber fusion. Fluorescence and transmission electron microscopy (TEM) measurements confirmed the evenly dispersion of the Q.D??s into nanofibers structures.     

Phylogenetic relationships of <Emphasis Type="Italic">Scomberomorus commerson</Emphasis> using sequence analysis of the mtDNA D-loop region in the Persian Gulf,Oman Sea and Arabian Sea

Narrow-barred Spanish mackerel, Scomberomorus commerson, is an epipelagic and migratory species of family Scombridae which have a significant role in terms of ecology and fishery. 100 samples were collected from the Persian Gulf, Oman Sea and Arabian Sea. Part of their dorsal fins was snipped and transferred to micro-tubes containing ethanol; then, DNAs were extracted and HRM-Real Time PCR was performed to designate representative specimens for sequencing. Phylogenetic relationships of S. commerson from Persian Gulf, Oman Sea and Arabian Sea were investigated using sequence data of mitochondrial DNA D-loop region. None clustered Neighbor Joining tree indicated the proximity amid S. commerson in four sites. As numbers demonstrated in sequence analyses of mitochondrial DNA D-Loop region a sublimely high degree of genetic similarity among S. commerson from the Persian Gulf and Oman Sea were perceived, thereafter, having one stock structure of S. commerson in four regions were proved, and this approximation can be merely justified by their migration process along the coasts of Oman Sea and Persian Gulf. Therefore, the assessment of distribution patterns of 20 haplotypes in the constructed phylogenetic tree using mtDNA D-Loop sequences ascertained that no significant clustering according to the sampling sites was concluded.     

The effects of dietary vitamin C on mucosal immune responses and growth performance in Caspian roach (Rutilus rutilus caspicus) fry

This study was conducted to investigate the effects of different levels of dietary vitamin C on some skin mucus immune parameters, mucus antimicrobial activity and growth performance of Caspian roach (Rutilus rutilus caspicus) fry. Six hundred sixty Caspian roach (1.4 ± 0.02 g) fry were allocated to 12 tanks (55 fish per tank), and triplicate groups were fed diets containing 0, 1,000, 1,500 and 2,000 mg kg^?1 vitamin C for 60 days. At the end of the trial, the epidermal mucus protein level, alkaline phosphatase and antimicrobial activity against two gram-positive bacteria (Streptococcus faecium and Micrococcus luteus) and gram-negative bacteria (Escherichia coli and Serratia marcescens) as well as growth performance were measured. The results demonstrated that feeding on vitamin C significantly elevated skin mucus alkaline phosphatase and protein levels compared to the control group (P < 0.05). However, lysozyme activity was undetectable in both the vitamin C-fed roach fry and the control group. Skin mucus antimicrobial activity was increased following vitamin C administration, and the bacterial growth inhibition zones were significantly elevated in vitamin C-fed roach (P < 0.05). Similar results were obtained in case of the minimum inhibitory concentration of skin mucus. Also fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). These results revealed that dietary vitamin C beneficially affects the skin mucus immune parameters and growth performance of Caspian roach fry.     

Evaluation of Neurogenic Potential of Human Umbilical Cord Mesenchymal Cells; a Time- and Concentration-Dependent Manner

Background:

Retinoic acid as one of the most important regulators for cell differentiation was examined in this study for differentiation of human umbilical mesenchymal cells (hUCM).

Methods:

After isolation, hUCM were evaluated for mesenchymal stem cell properties by flow cytometry and alkaline phosphatase assay. Also, doubling time of the cells and their differentiation potential into adipogenic and osteogenic cells were tested. hUCM were then cultured with different concentrations of retinoic acid, and on days 1, 7, and 12, the percentage of differentiated cells was determined by immunostaining for nestin, anti-microtubule associated protein 2 (MAP₂), glutamic acid decarboxylase (GAD), and gamma-aminobutyric acid (GABA) markers.

Results:

The isolated cells were negative for the hematopoietic markers and positive for the mesenchymal markers. They showed the population doubling time 60 ± 3 hours and differentiated into osteogenic and adipogenic cells. A descending trend in nestin and an ascending trend in MAP₂, GAD, and GABA expression were observed from the first day until the last day between different concentrations of retinoic acid.

Conclusion:

hUCM cells may have the potential to differentiate into neural cells in the presence of different incubation period and concentration of retinoic acid.Key Words: Cell differentiation, Neural stem cells, Retinoic acid     

Large-scale high throughput screening of sugar beet germplasm using a nanobiosensor and its comparison with ELISA method for resistance to Polymyxabetae

Identification of resistance resources of sugar beet germplasm against Polymyxa betae has always been a critical concern among sugar beet breeders. In the present study, two different methods including the DAS-enzyme-linked immunosorbent assay (ELISA) test and a nanobiosensor method based on florescent resonance transfer energy (FRET) were compared in order to achieve resistant germplasm. More specifically, 58 sugar beet germplasm as well as two negative and two positive controls were cultivated in infested soil under greenhouse conditions. The contamination level or in another words sensitivity and specificity observed based on the ELISA readings was inaccurately lower in comparison with the investigated nanobiosensor. Moreover, the nanobiosensor was 70 folds less time consuming compared to the ELISA method, for the immuno-reaction was much faster and no sample treatment steps were required. As a result, the quantum dots-FRET-based nanobiosensor investigated herein could well suit the task of everyday screening of resistance resource and could be efficiently used in breeding programs.     

Modulation of antioxidant defense and immune response in zebra fish (<Emphasis Type="Italic">Danio rerio</Emphasis>) using dietary sodium propionate

The present study explores the effect of dietary sodium propionate on mucosal immune response and expression of antioxidant enzyme genes in zebra fish (Danio rerio). Six hundred healthy zebra fish (0.42 ± 0.06 g) supplied, randomly stocked in 12 aquariums and fed on basal diets supplemented with different levels of sodium propionate [0 (control), 5, 10 and 20 g kg^?1] for 8 weeks. At the end of the feeding trial, mucosal immune parameters (TNF-α, IL-1β, Lyz), antioxidant enzyme (SOD, CAT) as well as heat shock protein 70 (HSP70) gene expression were measured. The results revealed feeding on sodium propionate significantly up-regulated inflammatory response genes (TNF-α, IL-1β, Lyz) in a dose-dependent manner (P < 0.05). However, antioxidant enzyme genes significantly down-regulated in the treated group compared with control (P < 0.05). Also, HSP70 gene expression was higher in the liver of fish fed the basal diet and deceased with elevation of sodium propionate levels in the diet. These results showed beneficial effects of dietary sodium propionate on mucosal immune response as well as the antioxidant defense of zebra fish.     

Mapping of Lr56 translocation recombinants in wheat

In an attempt to transfer the Lr56/Yr38 resistance loci from Aegilops sharonensis to wheat, a 6A‐6S^sh chromosome translocation was produced. It involves essentially the entire chromosome 6S^sh with a small terminal segment of 6AL. Induced homoeologous recombination of the translocated chromosome with 6A produced numerous recombinants including three recombined chromosomes carrying Lr56 that could not be precisely mapped for lack of suitable markers. This study aimed to determine the chromosomal locations of the translocation breakpoints in these three recombinants using various DNA markers as well as physical and genetic mapping. The three recombinants Lr56‐39, ‐157 and ‐175 carry small segments of Ae. sharonensis chromatin distally to the Xgpw4329 and IWA5416 loci near the 6AS telomere. The Ae. sharonensis chromatin that remains in each line includes a homoeolocus of the wheat marker locus Xdupw217 (on 6BS) and its characteristic amplification product can be used as a dominant marker for the presence of Lr56. Of the three recombined chromosomes, Lr56‐157 retained the least alien chromatin and appears to be the best candidate for use in wheat breeding.     

特色饮料“生命营养液”内源菌株CICC10822的鉴定及生物学特性

[目的]鉴定特色饮料"生命营养液"内源菌株CICC 10822并了解其生物学特性。[方法]采用传统微生物学分离培养方法对30℃条件下分离得到的新疆埃杜升"生命营养液"细菌CICC 10822进行多相分类鉴定。[结果]菌株CICC 10822接触酶反应阴性,硝酸盐还原阴性,淀粉水解阴性,精氨酸双水解酶阴性;能利用葡萄糖、果糖、核糖和半乳糖,不能利用麦芽糖、木糖、甘油、乳糖、甘露糖、山梨醇、纤维二糖、鼠李糖、阿拉伯糖,不液化明胶。利用基于形态学观察、生理生化特征分析及16S r DNA和phe S基因序列系统发育分析的微生物多相分类鉴定技术,将菌株CICC 10822鉴定为酸鱼乳杆菌(Lactobacillus acidipiscis)。[结论]试验结果为今后开展针对该菌的生物学功能研究奠定了基础。     

Cadmium (Cd) and Lead (Pb) Induced Changes in Growth,Some Biochemical Attributes,and Mineral Accumulation in Two Cultivars of Mung Bean [Vigna radiata (L.) Wilczek]

Addition of cadmium, lead, and cadmium + lead (Cd, Pb, and Cd+Pb) to growth medium leads to a reduction in seed germination, length, fresh and dry biomass of shoots and roots, total chlorophyll, chlorophyll a, chlorophyll b, and soluble proteins in plants. This study was undertaken on two mungbean cultivars (MN-92 and MN-98). Application of these metals in the growth medium reduced the bioabsorption of calcium (Ca), magnesium (Mg), and potassium (K). Concentrations of all the metals were greater in the roots than in the shoots except for K, which was greater in the shoots. Mungbean cultivar NM-98 performed better than NM-92 in response to heavy-metal toxicity. Overall, the metal-induced physiobiochemical changes resulted in reduced growth of both mungbean cultivars.