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11.
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Digestion of sucrose, fructose and glucose was studied in pigs with reentrant cannulas in the distal ileum or intact pigs fed diets formulated with sucrose, fructose and glucose as the major energy source and torula yeast. Sucrose and glucose were completely digested in the small intestine (apparent digestibility, 98.3 and 98.3%, respectively but a fraction of the dietary fructose escaped to the large intestine (adjusted value, 11.7%). There was no carbohydrate in rectal contents of the pigs. There was no carbohydrate influence on the pre-caecal or total digestibility of nitrogen.  相似文献   
13.
The purpose of this study is to elucidate both the chemical and conformational structure of an unfractionated fucoidan extracted from brown seaweed Turbinaria ornata collected at Nha-trang bay, Vietnam. Electrospray ionization mass spectrometry (ESI-MS) was used for determining the chemical structure and small angle X-ray scattering (SAXS) provided conformational of the structure at the molecular level. The results showed that the fucoidan has a sulfate content of 25.6% and is mainly composed of fucose and galactose residues (Fuc:Gal ≈ 3:1). ESIMS analysis suggested that the fucoidan has a backbone of 3-linked α-l-Fucp residues with branches, →4)-Galp(1→ at C-4 of the fucan chain. Sulfate groups are attached mostly at C-2 and sometimes at C-4 of both fucose and galactose residues. A molecular model of the fucoidan was built based on obtained chemical structure and scattering curves estimated from molecular model and observed SAXS measurement were fitted. The results indicated that fucoidan under study has a rod-like bulky chain conformation.  相似文献   
14.

Fineroots (≤ 2 mm diameter) are dynamic components of the forest ecosystems and play important role in water and nutrient acquisition in forests. These roots are sensitive to forest fertilization and therefore, the response of fineroots to nutrient application would provide better understanding of the forest carbon and nutrient dynamics that will be helpful in sustainable forest management plans. Two fertilization treatments, including (1) F400: 400 g P2O5 (16.5%)/tree and (2) F600: 600 g P2O5 /tree, and F0: control (without fertilization), were applied in an Acacia mangium plantation with a planting density of 1100 trees/ha (3 m?×?3 m). The evaluation of fineroot growth across seasons showed that fertilization significantly increased production and subsequent mortality and decomposition. The total decomposition associated with F600 application was 7.95 tons ha?1 year?1, equaling 121% of F400 and 160% of the control. Mortality in F600 was 8.75 tons ha?1 year?1, equaling 111% of F400 and 198% of F0, while production in F600 was 10.40 tons ha?1 year?1, equaling 127% of F400 and 143% of F0. Fineroot production, mortality, and decomposition are seasonally dependent, with higher values measured in the rainy season than in the dry season. Stand basal area increment was significantly correlated with fineroot production (R2?=?0.75), mortality (R2?=?0.44), and decomposition (R2?=?0.48). This study showed that fertilization could facilitate fineroot production, which can then lead to a higher turnover of carbon and nutrients through the decomposition of the greater mass of the fineroots.

  相似文献   
15.
Asian turtles are overharvested for food, medicinal purposes and pets, and most species are now at risk of extinction (‘Asian turtle crisis’). As a result of high levels of trade, some species of Asian turtles are known to science mostly or only from animals found in trade. The Vietnamese box turtle (Cuora picturata) was described in 1998 and is known only from markets. This species is likely to be highly threatened, and identifying the origin of this “market species” is imperative if it is to be conserved. We used evidence from phylogeny, biogeography and trade patterns to focus field searches for this species, and in July 2010–January 2011 found it in the wild at three localities on the Langbian Plateau of southern Vietnam. This discovery provides the first opportunity to conserve the Vietnamese box turtle, and provides hope for determining the wild origin of other rare Asian turtles that remain known only from commercial trade.  相似文献   
16.
Two studies were conducted to determine the impact of supplementation of diets containing ensiled cassava leaves as the main protein source with synthetic amino acids, dl-methionine alone or with L-lysine. In study 1, a total of 40 pigs in five units, all cross-breds between Large White and Mong Cai, with an average initial body weight of 20.5 kg were randomly assigned to four treatments consisting of a basal diet containing 45% of dry matter (DM) from ensiled cassava leaves (ECL) and ensiled cassava root supplemented with 0%, 0.05%, 0.1% and 0.15% dl-methionine (as DM). Results showed a significantly improved performance and protein gain by extra methionine. This reduced the feed cost by 2.6%, 7.2% and 7.5%, respectively. In study 2, there were three units and in each unit eight cross-bred (Large White × Mong Cai) pigs with an initial body weight of 20.1 kg were randomly assigned to the four treatments. The four diets were as follows: a basal diet containing 15% ECL (as DM) supplemented with different amounts of amino acids l-lysine and dl-methionine to the control diet. The results showed that diets with 15% of DM as ECL with supplementation of 0.2% lysine +0.1% dl-methionine and 0.1% lysine +0.05% dl-methionine at the 20–50 kg and above 50 kg, respectively, resulted in the best performance, protein gain and lowest costs for cross-bred (Large White × Mong Cai) pigs. Ensiled cassava leaves can be used as a protein supplement for feeding pigs provided the diets contain additional amounts of synthetic lysine and methionine.  相似文献   
17.
A series of experiments was carried out in 2012–2014 in Pailin province, Cambodia, to determine the potential and agronomic requirements for a dry season sunflower crop. The research showed that the six high-oleic sunflower hybrids evaluated were similar for phenological development and yield but two varieties had <50% emergence and poor hybrid seed quality was seen as a constraint to planting under rainfed conditions. Sunflower receiving a basal application of 20:20:15 (N:P2O5:K2O) at 200 kg ha?1 produced achene yield of 2423 kg?1, while side-dressing with urea had no effect on yield. Application of s-metolachlor post-sowing pre-emergence was the most effective weed control treatment and significantly increased sunflower achene yield. Post-emergence weed control was not adequate to prevent yield loss from weed competition. The study showed that sunflower can be grown successfully as a dry season crop in North-West Cambodia when planted no-tillage on residual soil water remaining after maize harvest in October and November. The critical requirements for success are related to preservation and effective use of residual soil water and include minimal soil disturbance, adequate application of fertiliser at sowing, and pre-emergence control of weeds, especially grasses.  相似文献   
18.
Three different fucoidan fractions were isolated and purified from the brown alga, Sargassum mcclurei. The SmF1 and SmF2 fucoidans are sulfated heteropolysaccharides that contain fucose, galactose, mannose, xylose and glucose. The SmF3 fucoidan is highly sulfated (35%) galactofucan, and the main chain of the polysaccharide contains a →3)-α-l-Fucp(2,4SO3)-(1→3)-α-l-Fucp(2,4SO3)-(1→ motif with 1,4-linked 3-sulfated α-l-Fucp inserts and 6-linked galactose on reducing end. Possible branching points include the 1,2,6- or 1,3,6-linked galactose and/or 1,3,4-linked fucose residues that could be glycosylated with terminal β-d-Galp residues or chains of alternating sulfated 1,3-linked α-l-Fucp and 1,4-linked β-d-Galp residues, which have been identified in galactofucans for the first time. Both α-l-Fucp and β-d-Galp residues are sulfated at C-2 and/or C-4 (and some C-6 of β-d-Galp) and potentially the C-3 of terminal β-d-Galp, 1,4-linked β-d-Galp and 1,4-linked α-l-Fucp residues. All fucoidans fractions were less cytotoxic and displayed colony formation inhibition in colon cancer DLD-1 cells. Therefore, these fucoidan fractions are potential antitumor agents.  相似文献   
19.
In order to purify rotor orbit,the characteristics of suppressing the phenomenon of mode mixing and filtering in ensemble empirical mode decomposition (EEMD) are studied,and a method of rotor orbit purification is presented. Ensemble empirical mode decomposition decomposes a complicated signal into a collection of intrinsic mode functions (IMFs). Then,according to prior knowledge of rotor system,choose intrinsic mode function components and reconstruct the signal,and,the purification of rotor orbit is obtained. The effectiveness of the method is proved by the successful purification of rotor orbit coming from the test-bed. And,the results of comparing the performances of the proposed method to the harmonic-based and the EMD-based purification of axis orbit method show the advantage of the de-noising method. The method provides a new way for fault diagnosis of rotating machinery.  相似文献   
20.
Ligularia fischeri (Ledeb.) Turcz, a commercial leafy vegetable, contains caffeoylquinic acid derivatives (CQAs) as major phenolic constituents. The HPLC chromatograms of leaf extracts collected from different areas in Korea showed a significant variation in CQA amount, and two tri-O-caffeoylquinic acids (triCQAs) were purified and structurally identified by NMR and MS from this plant. Radical scavenging activities among CQAs were found to be increased in proportion to the number of caffeoyl groups. Since this plant prefers damp and shady growth conditions, the effects of sunlight were investigated by growing plantlets in sunlight and shade for four weeks. Greater leaf thickness and higher phenolic contents were found for leaves grown in sunlight than in shade. Four major CQAs-5-mono-O-caffeoylquinic acid (5-monoCQA), and 3,4-, 3,5-, and 4,5-di-O-caffeoylquinic acid (diCQA)-were induced by solar irradiation, whereas the content of these compounds decreased steadily in shade leaves. The leaves of L. fischeri clearly showed adaptation responses to sunlight, and these characteristics can be exploited for cultivation of this plant for potential use as a nutraceutical and functional food.  相似文献   
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