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1.
Prediction of Fiber Composition and Silicification for Rice Straw with Near Infrared Reflectance Spectroscopy (NIRS) Technique 总被引:1,自引:0,他引:1
SHEN Heng-sheng CHEN Jun-chen ZHAO Wu-shan Ni De-bin TANG Bao-sha Valdes E V 《中国农业科学(英文版)》2002,1(10):1111-1115
The silicification of rice straw is a factor that affects the grain production and straw nutritive quality. The procedure of chemical analysis for silicon in straw is, however, time and labor consuming, and slightly poor in accuracy. The study has attempted to apply near infrared reflectance spectroscopy (NIRS)technique as an advanced alternative to predict the fiber composition and silicification in rice straw. Ninetytwo samples from different seasons and varieties were collected over the Fujian Province. Their chemical analyses were carried on the aspects of hemicellulose, cellulose, lignin, extractable and non-extractable silicon,and the results were used as a database for NIRS analyses. The prediction model was developed through modified partial least square regression (MPLS) for a calibration program. The factors that may affect the calibration, cross-validation and the prediction for the application of NIRS on rice straw were also discussed. 相似文献
2.
A study was undertaken in five draught horses of 648±33 kg body weight to find the effects of continuously pulling loads on their cardiovascular, respiratory and metabolic responses. A cart equipped with an odometer, for measuring distance, and a hydraulic dynamometer, for measuring draught force, was used. Heart and respiration rates and rectal temperatures were recorded. Blood samples for measuring arterial and venous pH and blood gases, haemoglobin, glucose and lactic acid concentrations and the serum activity of the enzymes creatine phosphokinase (CK), lactate dehydrogenase, aspartate aminotransferase and alkaline phosphatase were taken before exercise and immediately after each journey (morning and afternoon) of the daily work.Draught exercise, with loads which generated forces of between 0.57 and 0.59 kN, at speeds of 1.60 to 2.11 m/s, for 8 h daily for five consecutive days, with resting intervals of 10 min each hour, was well tolerated. Exercise tolerance was evaluated from the recovery from the changes observed in the biochemical and physiological parameters induced by the work. The analysis of these showed that, when the horses were subjected to prolonged periods of resting, their loss of fitness for work was shown by significant increases in the serum activity of muscle-derived enzymes and in blood lactate concentrations during the first day of work. However, over the following days the horses adapted to the work, so that the decreases in serum enzyme activities and blood lactate concentrations were reduced. Since similar observations have been described for racehorses, the determination of blood lactate concentrations and the serum activities of muscle-derived enzymes, specifically CK, seem to be good indicators of fitness in draught horses. 相似文献
3.
Seedling growth and ectomycorrhizal colonization of Pinus radiata and P. patula seedlings growing in nursery containers with two application rates of spores of 3 different ectomycorrhizal fungi, Helvella lacunosa, Russula brevipes and Lycoperdon perlatum, was evaluated at 5 and 12 months. At 5 months of growth P. patula was less susceptible than P. radiata to colonization by fungi and percentage of ectomycorrhizal feeder roots was lower in all treatments. Growth response (either volume or top dry weight) to treatments was different among pines species. A significant seedling growth response was observed after 5 months in both pine species with the double rate of spores of either H. lacunosa or L. perlatum; this response was sustained in P. patula at 12 months with Helvella only. P. radiata seedlings inoculated with the double rate of spores of R. brevipes showed a significant growth response at 12 months.
Resumen Se estudió en dos intervalos del crecimiento de Pinus patula y P. radiata, en envases de vivero, la inoculación con dos dosis de esporas de los hongos ectomicorrícicos Helvella lacunosa, Russula brevipes y Lycoperdon perlatum. P. patula se mostró, en la temprana edad (5 meses) menos susceptible a la colonización radicular por bongos; la proporción de sus raicillas micorrizadas es, en todos los tratamientos, mas baja que la del otro pino. La respuesta a la inoculación (volumen o peso seco) es diferente en las dos especies de pinos; a los 5 meses se observa en ambos un respuesta significativa a la doble dosis de esporas tanto de Helvella como de Lycoperdon. Esta respuesta es consistente a los 12 meses solo en P.patula inoculado con esporas de Helvella; en esta misma etapa, las plantulas de P.radiata inoculadas con la doble dosis de esporas de Russula mostraron una respuesta significativa en su crecimiento.相似文献
4.
Sammy Ramirez DVM MS Jamie Williams MS DVM Thomas L. Seahorn DVM MS Uriel Blas-Machado DVM Beth Paugh Partington DVM MS Miguel Valdes DVM MS J. Raymond McClure DVM MS 《Veterinary radiology & ultrasound》1998,39(2):143-146
A 3-month-old foal was presented for correction of bilateral angular limb deformities. Azotemia was detected as an incidental finding. Small, misshapened, hyperechoic kidneys with decreased corticomedullary demarcation were noted with ultrasonography. Additionally, the internal renal architecture was abnormal in that the intrarenal vessels and distant collecting system were not clearly seen in either kidney. Ultrasound-guided renal biopsy was suggestive of congenital renal dysplasia, which was later confirmed at necropsy. Clinical, sonographic, and pathologic features of equine renal dysplasia are discussed. 相似文献
5.
近红外漫反射光谱法(NIRS)分析稻草纤维及硅化物组成 总被引:7,自引:1,他引:7
水稻稻草硅质化是影响稻谷生产与稻草营养品质的主要因素之一 ,对水稻稻草硅化特点的化学分析费时、耗资、准确度较低。利用近红外漫反射光谱法 (NIRS)具有分析速度快、精度高、结果稳定的优点。对同年采自福建省不同种植地、不同季节、不同品种的稻草及稻叶、叶鞘、茎秆共 92份样品进行半纤维素、纤维素、木质素、可溶及不可溶性硅化物成分的近红外光谱分析。研究利用改进最小偏差 (改进最小二乘法回归技术 )回归法 (ModifiedPLS)进行定标建模 ,并进行交叉验证 (cross validation) ,探讨了用近红外漫反射光谱技术建立稻草纤维及硅化物组成快速预测模型的可行性 ,以及影响NIRS技术在建模应用中的主要因素。 相似文献
6.
Graciela Pineda‐Valdes Dojin Ryu David S. Jackson Lloyd B. Bullerman 《Cereal Chemistry》2002,79(6):779-782
The incidence of moniliformin (MON) producing Fusarium spp. in selected corn (Zea mays L.) samples from Mexico and the United States and the effects of alkaline cooking and the tortilla manufacturing processes on the reduction of MON were determined. The percentage of infected kernels with Fusarium spp. ranged from 0 to 22% in eight foodgrade corn samples, including six from Mexico and two from the United States. Complete (100%) reduction of MON was observed when a naturally contaminated corn sample containing 1.4 μg of MON/g of corn was used in a pilot‐scale alkaline cooking and tortilla manufacturing process. In a companion laboratory‐scale study, using a cultured corn sample containing 17.6 μg of MON/g of corn, a 71% reduction of the toxin was observed during the process. Alkaline cooking appeared to be an effective method for reduction of MON in corn. 相似文献
7.
An ideal surface for implantable glucose sensors would be able to evade the events leading to chronic inflammation and fibrosis, thereby extending its utility in an in vivo environment. Nafion?, a perfluorinated ionomer, is the membrane material preferred for in situ glucose sensors. Unfortunately, the surface properties of Nafion? promote random protein adsorption and eventual foreign body encapsulation, thus leading to loss of glucose signal over time. Details of the techniques to render Nafion? nonprotein fouling are given in a previous article [T. I. Valdes et al., Biomaterials 29, 1356 (2008)]. Once random protein adsorption is prevented, a biologically active peptide can be covalently bonded to the treated Nafion? to induce cellular adhesion. Cellular responses to these novel decorated Nafion? surfaces are detailed here, including cell viability, cell spreading, and type I collagen synthesis. Normal human dermal fibroblasts (NHDFs) were cultured on control and modified Nafion? surfaces. Findings indicate that Nafion? modified with 10% 2-hydroxyethyl methacrylate and 90% tetraglyme created a nonfouling surface that was subsequently decorated with the YRGDS peptide. NHDFs were shown to have exhibited decreased type I collagen production in comparison to NHDF cells on unmodified Nafion? surfaces. Here, the authors report evidence that proves that optimizing conditions to prevent protein adsorption and enhance cellular adhesion may eliminate fibrous encapsulation of an implant. 相似文献
8.
Gustavo Cabrera-Barjas Cristian Gonzlez Aleksandra Nesic Kelly P. Marrugo Oscar Gmez Cdric Delattre Oscar Valdes Heng Yin Gaston Bravo Juan Cea 《Marine drugs》2021,19(4)
β-chitin was isolated from marine waste, giant Humboldt squid Dosidicus gigas, and further converted to nanofibers by use of a collider machine under acidic conditions (pH 3). The FTIR, TGA, and NMR analysis confirmed the efficient extraction of β-chitin. The SEM, TEM, and XRD characterization results verified that β-chitin crystalline structure were maintained after mechanical treatment. The mean particle size of β-chitin nanofibers was in the range between 10 and 15 nm, according to the TEM analysis. In addition, the β-chitin nanofibers were converted into films by the simple solvent-casting and drying process at 60 °C. The obtained films had high lightness, which was evidenced by the CIELAB color test. Moreover, the films showed the medium swelling degree (250–290%) in aqueous solutions of different pH and good mechanical resistance in the range between 4 and 17 MPa, depending on film thickness. The results obtained in this work show that marine waste can be efficiently converted to biomaterial by use of mild extractive conditions and simple mechanical treatment, offering great potential for the future development of sustainable multifunctional materials for various industrial applications such as food packaging, agriculture, and/or wound dressing. 相似文献
9.
Daniel Robledo Leonardo Navarro‐Angulo David Valdes Lozano Yolanda Freile‐Pelegrín 《Aquaculture Research》2014,45(10):1648-1658
In this study, we have tested the effect of seaweed stocking density in an experimental seaweed biofilter using the economically important red seaweed Hydropuntia cornea integrated with the cultivation of the pink shrimp Farfantepenaeus brasiliensis. Nutrient removal efficiency was evaluated in relation to seaweed stocking density (2.5, 4, 6 and 8 g fw L?1). Total ammonia nitrogen (TAN) was the main nitrogen source excreted by F. brasiliensis, with concentrations ranging from 41.6 to 65 μM of NH4+‐N. H. cornea specific growth rates ranged from 0.8 ± 0.2 to 1.4 ± 0.5% day?1 with lowest growth rates at higher seaweed stocking density (8 g fw L?1). Nutrient removal was positively correlated with the cultivation densities in the system. TAN removal efficiency increased from 61 to 88.5% with increasing seaweed stocking density. Changes in the chemical composition of the seaweed were analysed and correlated with nutrient enrichment from shrimp effluent. The red seaweed H. cornea can be cultured and used to remove nutrients from shrimp effluents in an integrated multi‐trophic aquaculture system applied to a closed recirculation system. Recirculation through seaweed biofilters in land‐based intensive aquaculture farms can also be a tool to increase recirculation practices and establish full recirculation aquaculture systems (RAS) with all their known associated benefits. 相似文献
10.
Fabian A. Figueroa Roberto T. Abdala-Díaz Claudia Prez Virginia Casas-Arrojo Aleksandra Nesic Cecilia Tapia Carla Durn Oscar Valdes Carolina Parra Gastn Bravo-Arrepol Luis Soto Jos Becerra Gustavo Cabrera-Barjas 《Marine drugs》2022,20(7)
Codium bernabei is a green alga that grows on Chilean coasts. The composition of its structural polysaccharides is still unknown. Hence, the aim of this work is to isolate and characterize the hot water extracted polysaccharide fractions. For this purpose, the water extracts were further precipitated in alcohol (TPs) and acid media (APs), respectively. Both fractions were characterized using different physicochemical techniques such as GC-MS, GPC, FTIR, TGA, and SEM. It is confirmed that the extracted fractions are mainly made of sulfated galactan unit, with a degree of sulfation of 19.3% (TPs) and 17.4% (ATs) and a protein content of 3.5% in APs and 15.6% in TPs. Other neutral sugars such as xylose, glucose, galactose, fucose, mannose, and arabinose were found in a molar ratio (0.05:0.6:1.0:0.02:0.14:0.11) for TPs and (0.05:0.31:1.0:0.03:0.1:0.13) for ATs. The molecular weight of the polysaccharide samples was lower than 20 kDa. Both polysaccharides were thermally stable (Tonset > 190 °C) and showed antioxidant activity according to the ABTS•+ and DPPH tests, where TPs fractions had higher scavenging activity (35%) compared to the APs fractions. The PT and APTTS assays were used to measure the anticoagulant activity of the polysaccharide fractions. In general, the PT activity of the TPs and APs was not different from normal plasma values. The exception was the TPs treatment at 1000 µg mL−1 concentration. The APTTS test revealed that clotting time for both polysaccharides was prolonged regarding normal values at 1000 µg mL−1. Finally, the antitumor test in colorectal carcinoma (HTC-116) cell line, breast cancer (MCF-7) and human leukemia (HL-60) cell lines showed the cytotoxic effect of TPs and APs. Those results suggest the potential biotechnological application of sulfate galactan polysaccharides isolated from a Chilean marine resource. 相似文献