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1.
Cellulose nanocrystals (CNC) obtained by acidic hydrolysis from microcrystalline cellulose were dispersed in a biopolyurethane matrix to prepare composite films. The polyurethane was prepared from a hydroxylated soybean oil (SO‐OH) and a polymeric diphenyldiisocyanate (pMDI), using a organotin compound as the catalyst. The composite films contained different concentrations of nanocelullose, without any macroscopic aggregates in all cases. Thermal, tensile and dynamic mechanical properties of the films were determined for all the samples. In particular, it was observed that the glass transition temperature of the nanocomposites slightly increased with the concentration of the cellulose nanocrystals. The nanocomposite with 1 wt% of nanocellulose showed the highest tensile strength of the series. POLYM. ENG. SCI., 58:125–132, 2018. © 2017 Society of Plastics Engineers  相似文献   
2.
Genomic selection has been widely implemented in many livestock breeding programs, but it remains incipient in buffalo. Therefore, this study aimed to (1) estimate variance components incorporating genomic information in Murrah buffalo; (2) evaluate the performance of genomic prediction for milk-related traits using single- and multitrait random regression models (RRM) and the single-step genomic best linear unbiased prediction approach; and (3) estimate longitudinal SNP effects and candidate genes potentially associated with time-dependent variation in milk, fat, and protein yields, as well as somatic cell score (SCS) in multiple parities. The data used to estimate the genetic parameters consisted of a total of 323,140 test-day records. The average daily heritability estimates were moderate (0.35 ± 0.02 for milk yield, 0.22 ± 0.03 for fat yield, 0.42 ± 0.03 for protein yield, and 0.16 ± 0.03 for SCS). The highest heritability estimates, considering all traits studied, were observed between 20 and 280 d in milk (DIM). The genetic correlation estimates at different DIM among the evaluated traits ranged from ?0.10 (156 to 185 DIM for SCS) to 0.61 (36 to 65 DIM for fat yield). In general, direct selection for any of the traits evaluated is expected to result in indirect genetic gains for milk yield, fat yield, and protein yield but also increase SCS at certain lactation stages, which is undesirable. The predicted RRM coefficients were used to derive the genomic estimated breeding values (GEBV) for each time point (from 5 to 305 DIM). In general, the tuning parameters evaluated when constructing the hybrid genomic relationship matrices had a small effect on the GEBV accuracy and a greater effect on the bias estimates. The SNP solutions were back-solved from the GEBV predicted from the Legendre random regression coefficients, which were then used to estimate the longitudinal SNP effects (from 5 to 305 DIM). The daily SNP effect for 3 different lactation stages were performed considering 3 different lactation stages for each trait and parity: from 5 to 70, from 71 to 150, and from 151 to 305 DIM. Important genomic regions related to the analyzed traits and parities that explain more than 0.50% of the total additive genetic variance were selected for further analyses of candidate genes. In general, similar potential candidate genes were found between traits, but our results suggest evidence of differential sets of candidate genes underlying the phenotypic expression of the traits across parities. These results contribute to a better understanding of the genetic architecture of milk production traits in dairy buffalo and reinforce the relevance of incorporating genomic information to genetically evaluate longitudinal traits in dairy buffalo. Furthermore, the candidate genes identified can be used as target genes in future functional genomics studies.  相似文献   
3.

Objective

Among other neuroimaging techniques, functional magnetic resonance imaging (fMRI) can be useful for studying the development of motor fatigue. The aim of this study was to identify differences in cortical neuronal activation in nine subjects on three motor tasks: right-hand movement with minimum, maximum, and post-fatigue maximum finger flexion.

Materials and methods

fMRI activation maps for each subject and during each condition were obtained by estimating the optimal model of the hemodynamic response function (HRF) out of four standard HRF models and an individual-based HRF model (ibHRF).

Results

ibHRF was selected as the optimal model in six out of nine subjects for minimum movement, in five out of nine for maximum movement, and in eight out of nine for post-fatigue maximum movement. As compared to maximum movement, a large reduction in the total number of active voxels (primary sensorimotor area, supplementary motor area and cerebellum) was observed in post-fatigue maximum movement.

Conclusion

This is the first approach to the evaluation of long-lasting contraction effort in healthy subjects by means of the fMRI paradigm with the use of an individual-based hemodynamic response. The results may be relevant for defining a baseline in future studies on central fatigue in patients with neuropathological disorders.  相似文献   
4.

Objective

We demonstrate the potential clinical utility of a 4D non-gadolinium dynamic angiography technique based on arterial spin-labeling called contrast inherent inflow enhanced multi-phase angiography (CINEMA) in pediatric patients.

Materials and Methods

CINEMA was qualitatively compared to conventional time-of-flight (TOF) angiography in a cohort of 31 pediatric patients at 3 Tesla.

Results

CINEMA data were successfully acquired and reconstructed in all patients with no image artifacts. There were no cases where CINEMA was rated inferior to TOF in depicting intracranial vessel conspicuity. In 19 cases, CINEMA was rated equivalent to TOF and in the 12 remaining cases CINEMA was rated superior to TOF.

Conclusion

There is a steadily rising concern in adults and children over the potential effects of intracranial deposition of gadolinium. CINEMA is therefore a viable alternative in dynamic neurovascular imaging.
  相似文献   
5.
Fungal strains were screened for lipase producing activities and 10 strains were classified as good producers. Aspergillus sp., Fusarium sp., and Penicillium sp. exhibited the highest activities when fermented in wheat bran (WB) and soybean bran (SB). No fungal growth was observed using sugarcane bagasse (CB). An experimental design was applied to incorporate CB into the fermentation process for lipase production by Aspergillus sp. and Penicillium sp., and to evaluate the best moisture content for the substrate. Strains studied achieved maximum lipase activities with 25% CB combined with 75% WB or SB at 40% moisture content. The highest lipase activities were observed for WB and SB, and for SB combined with CB using Aspergillus sp. Fermentation of 96 h was the optimum period for enzyme production.  相似文献   
6.
Metallurgical and Materials Transactions B - The determination of the Magnesium level in a Titanium reduction retort by inductive methods is often hampered by the formation of Titanium sponge rings...  相似文献   
7.
This paper reveals new contributions to the analysis and development of devices for harmonic distortion mitigation. Considering the sequential distribution of harmonic currents, zero-sequence components could be diminished using electromagnetic devices, particularly the eZSB (electromagnetic zero-sequence blocking). One important characteristic of this device, which has received particular attention on this research, is its robustness and low cost of construction. Theoretical and experimental results related to the behavior of the electromagnetic blocking devices are presented. The results illustrate the consistence of the theoretical aspects related with the model in the frequency domain, as well as the performance of the blocking devices, reducing zero-sequence harmonic currents, mainly by the conjunct action of the eZSF (electromagnetic zero-sequence harmonic filter), working as a impedance coupler. In this context, aiming the evaluation of the reliability of the results obtained through mathematical modeling, experimental tests have been carried out using a low-power prototype, highlighting particular aspects related to its function as a zero-sequence harmonic blocker.  相似文献   
8.
The aim of the present study was to upgrade the bonding quality and water resistance of medium-density particleboards based on rice husks (RH) as a wood substitute and soybean protein concentrate (SPC) as the binder via chemical modification of SPC. Alkali (A), citric acid (CA) and boric acid (BA) were used to modify proteins and the carbohydrate complex in SPC. The effect of chemical treatment performed on SPC was followed by Fourier transform infrared, differential scanning calorimetry, thermo-gravimetric analysis and initial apparent viscosity measurements. Board properties were evaluated in terms of internal bond (IB) and physical properties. Results revealed that boards bonded with SPC treated with boric acid, exhibited the highest IB and the lowest water absorption and thickness swelling at 2 and 24 h, due to cross-linking reactions with exposed OH-groups in the amorphous region of cellulose of RH. Results demonstrate that boric acid-modified–SPC-bonded boards met the requirements of IB recommended by the US Standard ANSI A208.1-2009 for M1, MS, M2 and M3-grade medium-density particleboards but failed to pass the thickness swelling required. This issue of BSPC-RH boards is compensated for by the benefit of being formaldehyde-free which makes them suitable for indoor applications.  相似文献   
9.
10.
The freeze-dried sprouts’ juice of Raphanus sativus (L.) cv. Sango was prepared and analysed for the first time. HPLC analysis of total isothiocyanates, after protein displacement, resulted in 77.8 ± 3.0 μmol/g of dry juice while GC–MS analysis of hexane and acetone extracts showed E- and Z-raphasatin (8.9 and 0.11 μmol/g, respectively) and sulforaphene (11.7 μmol/g), summing up to 20.7 ± 1.7 μmol/g of free isothiocyanates. Sprouts’ juice contained an unprecedented wealth of anthocyanins and a new fractionation methodology allowed us to isolate 34 mg/g of acylated anthocyanins (28.3 ± 1.9 μmol/g), belonging selectively to the cyanidin family. Analysis was performed by HPLC–PDA–ESI–MSn and extended to deacylated anthocyanins and aglycones, obtained, respectively, by alkaline and acid hydrolysis. This study identified 70 anthocyanins, 19 of which have never been described before and 32 of which are reported here in R. sativus for the first time. Sango radish sprouts are exceptional dietary sources of heath-promoting micronutrients.  相似文献   
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