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181.
Kihoon Kim Jong Yoon Lee Hyun Kim Jaiho Shin Yongwon Shin Young Tai Yoo Hwi-Yool Kim 《Fibers and Polymers》2017,18(2):231-239
In recent decades, tremendous research has focused on the production of nanoscale fibers using synthetic polymers, with the goal of fabricating nanofibrous scaffolds for wound healing. However, the hydrophobicity of such polymers typically hinders attachment and proliferation of the cells. In this study, we combined poly-d,l-lactide-co-glycolide (PLGA) and small intestine submucosa (SIS) to fabricate blended nanofibers for wound healing by electrospinning. PLGA and SIS were dissolved in 1,1,1,3,3,3-hexafluoro isopropanol to produce different weight ratios of PLGA/SIS-blended nanofibrous membranes (NFM). Physicochemical characterization of the electrospun NFM was performed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle analysis, degradation test and tensile testing. The PLGA/SIS-blended NFM showed improved hydrophilicity and tensile strength. Better infiltration, attachment and proliferation of rat granulation fibroblasts of PLGA/SIS-blended NFMs compared to PLGA NFMs were identified by morphological differences determined by SEM and a water-soluble tetrazolium salt assay kit. Based on our results, the PLGA/SIS blended NFMs were found to be suitable for use as a potential material for wound dressing. 相似文献
182.
Wang Shi-fa Zhang Ai-jun 《中国林学(英文版)》2007,9(1):57-62
The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290°C during 8 min (the conditions were similar to those employed on an industrial scale). The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry (GC-MS). The analytical r... 相似文献
183.
Echinochloa crus-galli (L.) P. Beauv. (barnyardgrass) is an annual weed that is native to Asia and found throughout the world. The broad ecological
tolerance and competitive ability of E. crus-galli makes it the most important weed species in rice. Genetic studies of plants are becoming increasingly common because reliable
information is necessary to better understand population dynamics, occurrence of herbicide resistance, and demographic data.
Echinochloa crus-galli populations from 34 different locations in Turkey were compared with respect to morphological differences and genetic variation.
For morphological variation, five seeds of each population were sown in pots and grown in a screenhouse using a randomized
block design. Morphological parameters such as germination speed, flowering time, leaf area, plant height, spikelet length,
above-ground biomass, root dry weight and number of seeds were measured. Distinct differences among populations with respect
to hierarchical cluster analysis were observed. Genetic variations among populations were performed using random amplified
polymorphic DNA (RAPD) markers. The seven RAPD primers amplified 55 bands whose molecular weight varied between 200 and 4000 bp.
The percentage of polymorphic bands was 74.54%. Results showed high morphological and genetic variability among individual
genotypes within geographic locations. Phenotypic and genetic variability among E. crus-galli populations would be influenced by agricultural practices, crop characteristics, geographic location and herbicide pressure.
Differences between weed populations may affect response to chemical or biological control. 相似文献
184.
Esakky Ramachandran Suchit Ashish John Gerard Abraham Partha Sarathi Bhattacharya 《Journal of Crop Science and Biotechnology》2011,14(4):275-279
The PTM3 (MADS-box) gene characterized from flower of Aspen was ectopically expressed in cotton and was found to result in desirable
agronomic traits. Among several transgenic lines, the PTM3 cotton event-10 was found to flower significantly earlier than
the control and yield better [Ramachandran et al. (2011)]. We report our findings on performance based on greenhouse evaluation
and inheritance of PTM3 cotton event-10. The T1 progeny of event-10 were grown in pots under RBD design. The progeny were confirmed by kanamycin imbibition test, PCR, and
GUS assay which showed the segregation of transgene at about 3:1 ratio. GUS assay was performed with pollen from all transgenic
plants; plants that expressed gus in all pollen versus those that showed segregation for expression were found to be at a
ratio of 1:2. Similar to observations made in the T0 generation of event-10, the agronomic evaluation of T1 progeny exhibited, on an average, earliness of 13 days in flowering, 13.5 days in crop maturity, and 22% of yield enhancement.
The T2 progeny of homozygous lines were grown on field soil in the greenhouse under strip trial design to see the effect as observed
from potted plants of T1 progeny. Inheritance of transgene cassette to T2 progeny was confirmed by the same tests used to analyze T1 progeny. As exhibited by T0 and T1 progenies, the T2 progeny also showed earliness of 8 days in flowering, 12 days in crop maturity, and 17% of yield enhancement. The data generated
from the progeny over two generations confirms that the PTM3 cotton event-10 is superior in agronomic characters as compared
to non-transgenic cotton and is of interest for breeding shorter duration varieties with improved yield. 相似文献
185.
AGPT and HA tests were employed for rapid diagnosis of PPRV infection in sheep and goats in Sudan. Forty lymph nodes and spleen
samples from suspected cases of PPR in both sheep and goats were examined by AGPT and HA tests for detection of PPRV antigen.
Viral antigen was detected from (77.5%) of the samples tested by AGPT and (92.5%) tested by HA test. The results of both tests
revealed that HA test was more sensitive than AGPT for detection of PPRV antigen (Kappa statistics 0.4366). Another advantage
of the HA test over AGPT was that it can differentiate PPRV from RPV. Thus the HA test represents a quick, easy, simple, cheap
and reliable confirmatory test for the diagnosis of PPR and differential diagnosis of PPRV and RPV. The HA test was carried
out using chicken, goat and pig RBCs. Chicken RBCs were found to be the most sensitive for detection of PPRV antigen, followed
by goat then pig RBCs. The HA time when using chicken RBCs was 20–25 minutes, using goat RBCs was 25–30 minutes and using
pig RBCs was 40–45 minutes. The distribution of PPR infection in four different regions of Sudan was investigated. 相似文献
186.
Improvement of both the tensile and impact strength of the same polymeric material has always been a great challenge for the plastic industry. The study focuses on the effect of incorporation of calcium carbonate nanoparticles (0.3 wt% to 15 wt%) into three polypropylene (PP) based matrices viz. PP homopolymer, propylene-ethylene (PP-PE) copolymer and the blend of PP:PP-PE (30:70) to improve their impact behavior without hampering the tensile strength much. A loss in both the tensile and impact properties was observed in PP based nanocomposite. However, PP-PE based nanocomposites showed a significant improvement in impact strength (47 %) at 10 wt% loading with a loss of tensile strength by 22 %. To minimize this loss a blend of PP:PP-PE (30:70) was explored as a matrix. At 10 wt% loading, this matrix showed an improvement of 30 % in impact strength whereas the tensile loss was minimized to 10 %. Further, silane coupling agent which promoted good interfacial adhesion was used for best compositions. The variation of crystalline morphology of the nanocomposites with various formulations was analyzed using differential scanning calorimetry and X-ray diffraction. 相似文献
187.
Sung Ok Sohn So Min Lee Yun Mi Kim Jeong Hyun Yeum Jin Hyun Choi Han Do Ghim 《Fibers and Polymers》2007,8(2):163-167
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender
oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist
the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing
LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics
was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde
(MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET
fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing,
PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative
release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent
for durable aroma finishing of PET fabrics. 相似文献
188.
Background, Aim and Scope
Contamination of soils does not only occur on their surface over large areas, but also in depth. Therefore a characterization
of soil state after pollution demands a three-dimensional soil sampling, by what a large number of samples has to be analyzed.
Analytical results could be evaluated by multivariate statistical methods, which have already been used for the evaluation
of data sets containing results from soil sampling of two dimensions like areas or single profiles. In this case study, multivariate
statistical methods were applied to investigate structure and interactions between features in a data set containing results
of three-dimensional soil sampling. The investigated soil profiles were contaminated by emissions of a former cement and phosphate
fertilizer plant. The aim of this study was to determine the remaining extent of contamination and to analyze whether pollutants
are mobilized and vertically transported within the profiles.
Materials and Methods:
Three soil profiles were sampled in the surroundings of the plant. Grain size, organic and carbonatic bonded carbon, pH value,
and the total contents of Ca, Cd, Co, Cu, F, Fe, K, Mn, Mg, Na, Ni, P, Pb, and Zn were determined. The resulting data set
was evaluated by cluster analysis, linear discriminant analysis, and principal components analysis. The sequential extraction
procedure according to Zeien and Brümmer was applied to analyze the binding properties of Ca, Cd, Cu, Na, Pb, and Zn from
selected samples.
Results:
Cd was identified as contaminant of the top soils. The pH values of the bottom soils were determined to be in alkaline range,
which is unnaturally high. Variables were clustered according to enrichment of variables in top soils. The samples were classified
regarding their pollution state and their substrate by cluster analysis, which was confirmed by linear discriminant analysis.
Geogenic and anthropogenic sources of variables as well as relationships between variables like the binding of heavy metals
at organic matter were detected by using principal components analysis. The binding of heavy metals at organic matter in the
top soils was confirmed by the results of the applied sequential extraction. A vertically altered distribution of Na binding
was determined.
Discussion:
According to the current soil conditions, the uptake of heavy metals had probably occurred by the over ground part of plants
during the deposition. The distribution of Na should likely result from the vertical transport of Na, which would also explain
the high pH values of the bottom soils by ion exchange. Altogether, the main amount of deposited Ca, F, Na, P, and heavy metals
is likely nearly insoluble bound in the top soils.
Conclusions:
Ten years after the end of production, the pollution of top soils in the surroundings of the former plant is still high. However,
regarding the ecotoxicological relevance the now explored interactions between several soil features and elements strongly
indicate that there is no short-term to medium-term risk of a mobilization of the deposited elements with the exception of
Na.
Recommendations and Perspectives:
The results of this case study prove that multivariate statistical methods are powerful tools to explore interactions of variables
and relationships in a data set derived from three dimensional soil sampling. The methods applied in this work can be highly
recommended for evaluations of large data sets resulting from two- or three-dimensional samplings. Multivariate statistical
methods enable the characterization of soils and their pollution state in a simple and economic way. 相似文献
189.
Rocío Toraya-Avilés Maira Segura-Campos Luis Chel-Guerrero David Betancur-Ancona 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):149-155
Cassava (Manihot esculenta Crantz) native starch was treated with pyroconversion and enzymatic hydrolysis to produce a pyrodextrin and an enzyme-resistant maltodextrin. Some nutritional characteristics were quantified for both compounds. Pyroconversion was done using a 160:1 (p/v) starch:HCl ratio, 90 °C temperature and 3 h reaction time. The resulting pyrodextrin contained 46.21% indigestible starch and 78.86% dietary fiber. Thermostable α-amylase (0.01%) was used to hydrolyze the pyrodextrin at 95 °C for 5 min. The resulting resistant maltodextrin contained 24.45% dextrose equivalents, 56.06% indigestible starch and 86.62% dietary fiber. Compared to the cassava native starch, the pyrodextrin exhibited 56% solubility at room temperature and the resistant maltodextrin 100%. The glycemic index value for the resistant maltodextrin was 59% in healthy persons. Its high indigestible starch and dietary fiber contents, as well as its complete solubility, make the resistant maltodextrin a promising ingredient for raising dietary fiber content in a wide range of foods, especially in drinks, dairy products, creams and soups. 相似文献
190.
Sarah Figueiredo Martins Bonilha Renata Helena Branco Maria Eugênia Zerlotti Mercadante Joslaine Noely dos Santos Gonçalves Cyrillo Fábio Morato Monteiro Enilson Geraldo Ribeiro 《Tropical animal health and production》2017,49(3):529-535
Understanding the reasons why animals of similar performances have different feed requirements is important to increase profits for cattle producers and to decrease the environmental footprint of beef cattle production. This study was carried out aiming to identify the associations between residual feed intake (RFI) and animal performance, nutrient digestibility, and blood metabolites related to energy balance of young Nellore bulls during the finishing period. Animals previously classified as low (n?=?13) and high RFI (n?=?12), with average initial body weight of 398 kg and age of 503 days were used. Cattle were fed a high energy diet and were slaughtered when rib fat thickness measured by ultrasound between the 12th and 13th ribs reached the minimum of 4 mm. A completely randomized design was adopted, being data analyzed with a mixed model that included the random effect of slaughter group, the fixed effect of RFI class, and linear effect of the covariate feedlot time. No differences were found (p?>?0.10) between RFI classes for performance, dry matter, and nutrients intake. However, dry (p?=?0.0911) and organic matter (p?=?0.0876) digestibility tended to be lower, and digestibility of neutral detergent fiber corrected for ash and protein (p?=?0.0017), and total digestible nutrients (p?=?0.0657) were lower for high RFI animals, indicating lesser capacity of food utilization. Difference between low and high RFI animals was also found for blood cortisol at the end of the trial (p?=?0.0044), having low RFI animals lower cortisol concentrations. Differences in the ability to digest food can affect the efficiency of transforming feed into meat by Nellore cattle. 相似文献