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11.
Large amounts of seagrass, Posidonia australis, wash onto beaches in South Australia each year, causing substantial environmental problems. It was of interest to assess the potential for an economic use of this seagrass-such as for animal nutrition. Structural constituents of P. australis (green, freshly deposited, and both washed and unwashed samples from dried deposits on the beach) were examined and compared. Glucose, galactose, and mannose were the dominant sugars (>10 g kg-1 of dry matter) in the soluble fraction of nonstarch polysaccharides in all seagrass forms. The content of the insoluble constituents of the nonstarch polysaccharides was significantly higher than soluble nonstarch polysaccharide constituents (P < 0.01). Data showed that the major constituents of the Posidonia cell wall are cellulose and lignin (190-209 and 145-154 g kg-1, respectively). The crude protein content of Posidonia ranged from 54 to 61 g kg-1. Results showed no biologically significant compositional differences between the four different forms of seagrass tested. Dry, unwashed seagrass, which is readily available in large quantities and easily harvested, may have potential as a foodstuff for ruminant animals.  相似文献   
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In this study, average weight, colour, soluble solids content and titratable acidity were determined as quality parameters of strawberry fruits while ascorbic acid, total anthocyanins, total phenolics, total flavonoids, minerals and trace elements content as nutritional parameters. All these attributes along with the DPPH radical scavenging activity were screened in two strawberry genotypes grown on the same site at the ripe stage. Also, the phenolic profiles of the strawberry fruits were obtained by HPLC. Except colour, results showed no significant differences between cultivars in quality parameters. Ascorbic acid found for ‘Premial’ cv. (81.62?mg/100?g) was twice the amount found in ‘Magic’ cv. (42.15?mg/100?g), total phenolics varied from 207.95 (cv. ‘Premial’) to 249.98 (cv. ‘Magic’) mg GAE/100?g while total flavonoid content in fruits of ‘Magic’ cultivar (79.56?mg/100?g) was 2?fold higher than the one of the ‘Premial’ cv. The quercetin content ranged from 2.72 to 4.66?mg/100?g, whereas free ellagic acid ranged from 6.79 to 9.03?mg/100?g. The pale shiny fruits of ‘Premial’ cv. (higher L*, ho and chroma index) had a lower total anthocyanin content (19.07?mg CG/100?g) than the bluish fruits of the ‘Magic’ cv. (23.96?mg CG/100?g). An inverse relationship between the levels of ascorbic acid and anthocyanin contents was also noticed in strawberry samples. Significant differences were found also in minerals and trace elements content of the two strawberry cultivars. The results revealed the importance of genetic background for the content of antioxidant compounds in strawberry fruits.  相似文献   
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Hatchery culture of mud crabs has not yet achieved commercial viability despite decades of research efforts. Further research is therefore needed to better understand larval culture requirements of the crab. Based on anecdotal observations, an experiment was carried out to test whether the background colour of the culture vessel affected larval culture success. Newly hatched larvae of Scylla serrata were reared in culture vessels of five colours, i.e., black, dark green, maroon, sky blue and white. Larval survival and development were monitored daily until all of them either moulted to the first crab stage or died. The results showed clear effects of background colour on larval survival. A general tendency of higher larval survival in darker‐coloured backgrounds was evident. In particular, overall zoeal survival for larvae reared in black vessels was significantly higher than those reared in white ones. Background colour also appeared to affect larval development. Larvae reared in darker backgrounds generally had shorter development times and more synchronized moulting. A significant delay in zoeal development was observed in larvae reared in white vessels. Dark backgrounds possibly facilitated more efficient feeding, reduced settlement of larvae at the bottom of the vessels as well as minimized stress. This result appears to be the first to demonstrate that background colour can significantly affect larval survival and development of a crustacean species.  相似文献   
14.
The constituents of the red seaweedLaurencia papillosa were investigated in different seasons. Protein and galactan comprised the major components of the algal material. Acid hydrolysis of the alga afforded galactose, glucose, xylose, ribose and glucuronic acid. The alga was shown to contain cholesterol, -sitosterol and lanosterol. Free amino acids as well as the amino acid composition of the isolated proteins were also investigated. The algal components showed different seasonal variations.
Zusammenfassung Der rote SeetangLaurencia papillosa wurde zu verschiedenen Jahreszeiten auf seine Bestandteile hin untersucht. Protein und Galactan bilden die Hauptbestandteile des Algenmaterials. Säurehydrolyse der Alge ergibt Galactose, Glucose, Xylose, Ribose und Glucuronsäure. Die Alge enthält ferner Cholesterol, -Sitosterol und Lanosterol. Die freien Aminosäuren wurden ebenso untersucht wie die Aminosäuren-Zusammensetzung der isolierten Proteine. Die Bestandteile der Alge zeigten unterschiedliche jahreszeitliche Schwankungen.

Résumé Les constituants du rouge algueLaurencia papillosa ont été examinés dans les differentes saisons. Protéines et galactane ont composé la majorité des contenants du materiel algual. L'acide hydrolysé d'algue a offré galactose, glucose, xylose, ribose et glucuronique acide. L'algue a été paru comprendre cholesterol, -sitosterol et lanosterol. Les libres amino acides comme l'amino acid composition du protéine isolé ont été encore examinés. Les contenants alguales ont manifesté des differentes variations saisonales.
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OBJECTIVE: To evaluate the effect of focused extracorporeal shock wave therapy (ESWT) and radial pressure wave therapy (RPWT) on immunohistochemical staining for substance P and calcitonin gene-related peptide (CGRP) in the skin and periosteum of sheep. ANIMALS: 36 sheep. PROCEDURES: All 4 limbs of 36 sheep were treated with ESWT, RPWT, or a sham treatment. For 14 days after treatment, at least 2 sheep were euthanized daily and tissue was harvested for histologic evaluation of nerves via staining for substance P and CGRP in the skin and periosteum. RESULTS: No effects of ESWT or RPWT were observed on the number of nerves with stain uptake for substance P or CGRP in the skin or periosteum. CONCLUSIONS AND CLINICAL RELEVANCE: Substance P- and CGRP-containing nerve fibers are not disrupted by EWST or RPWT. Further studies are needed to identify the mechanism of analgesia observed in association with these treatment modalities.  相似文献   
17.
Measurement of soil bulk density is important for understanding the physical, chemical, and biological properties of soil. Accurate and rapid soil bulk density measurement techniques play a significant role in agricultural experimental research. This review is a comprehensive summary of existing measurement methods and evaluates their advantages, disadvantages, potential sources of error, and directions for future development. These techniques can be broadly categorised as direct and indirect methods. Direct methods include core, clod, and excavation sampling, whereas indirect methods include the radiation and regression approaches. The core method is most widely used, but it is time consuming and difficult to use for sampling multiple soil depths. The size of the coring cylinder used, operator experience, sampling depth, and in-situ soil moisture content significantly affect its accuracy. The clod method is suitable for use with heavy clay soils, and its accuracy is dependent on equipment calibration, drying time, and operator experience, but the process is complicated and time consuming. Excavation techniques are most commonly used to evaluate the bulk density of forest soils, but have major limitations as they cannot be used in soils with large pores and their measurement accuracy is strongly influenced by soil texture and the type of analysis selected. The indirect methods appear to have greater accuracy than direct approaches, but have higher costs, are more complex, and require greater operator experience. One such approach uses gamma radiation, and its accuracy is strongly influenced by soil depth. Regression methods are economical as they can make indirect measurements, but these depend on good, quality data of soil texture and organic matter content and geographical and climatic properties. Also, like most of the other approaches, its accuracy decreases with sampling depth.  相似文献   
18.
A field study was conducted at Al-Mishkhab Rice Research Station (MRRS) during the summer season 2009 to evaluate irrigation water use efficiency (IWUE) using Anbar 33 variety with the System of Rice Intensification compared to traditional methods. During the growth phase, the number of leaves, stems, and roots, and the average plant height were measured every 15 days for the two sets of methods. At maturity, the depth and length of plant roots was assessed, along with leaf area index (LAI) of the flag leaf and plant height. The amount of irrigation water applied was measured by water meter for both methods. SRI principles for plant age, spacing, etc., were implemented in the SRI plots. The results indicated more vigorous growth of roots under SRI methods, reaching 13,004 cm plant−1 compared with non-SRI results of 4,722 cm plant−1. There was 42% increase in grain yield when SRI methods were used. These had water use efficiency (WUE) of 0.291 kg m−2 compared with WUE of 0.108 kg m−2 for non-SRI cultivation, almost a threefold difference. SRI practices reduced the need for irrigation water by 38.5%.  相似文献   
19.
In this study, cryopreservation feasibility of Persian sturgeon (Acipenser persicus) and the effect of different doses of 2‐hydroxypropyl‐beta‐cyclodextrin on thawed spermatozoa quality (motility duration and motility percentage) were investigated. For freezing, semen of seven male individuals was pooled in equal volumes and diluted with 4°C [Tris‐HCl (100 mM), pH = 8, DMSO 10%] extenders containing 0, 5, 10, 15 mM of HβCD in a ratio of 1:1(semen/extenders). Then semen was filled into 0.5‐mL straws, and was frozen with vapour of liquid nitrogen at 4‐cm above surface of liquid nitrogen. After 3 min, straws were plunged in to liquid nitrogen. Thawing was performed at 40°C water baths for 15 s. Motility duration of the 10 mM HβCD treated spermatozoa at days 14 (228.98 ± 16.39) and 56 (199.66 ±21.78) were longer than other treatments. In day 56, the motility percentage in treatment with 10 mM was significantly higher (16.14 ± 2.54) (P < 0.05) compared with 5 mM treatment (8.75 ± 2.47) (P < 0.05). Therefore, it is recommended that 10 mM of HβCD can be used as an additive cryoprotectant for increasing cryopreserved spermatozoa quality in this species.  相似文献   
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