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31.
32.
Summary The problem of grading of fresh cacao beans for breeding and for taxonomic purpose is discussed. Seven grades are based on the color of transversal cutting of the cotyledons in fully mature beans, and the colors (plate) refer to color standards, namely:Grade 7 attributed to the true Criollos (two types and hybrid) as well as to Porcelain (with a short discussion on this cacao);Grade 6 to the Commerical Criollos (Almost-Criollos);Grade 5 to the Superior Forastero, chiefly Venezuelan Forastero;Grade 4 to the Average Forastero, typified with the Trinitarian Forastero;Grade 3 to the Low grade Forastero, probably corresponding to the Orinocan Forastero;Grade 2 attributed to the Almost Calabacillo (in part corresponding to the Amazonian Forastero);Grade 1 for true Calabacillo. Several examples of cacao grading for regions of Venezuela (and elsewere) and for the kind of cacao are selected, with an example of the yearly fluctuation of the grade in the same tree or cacao. The pod grade value (P.G.V.) as weighted average, is discussed.With one plate  相似文献   
33.

Background

Longitudinal tears in the lateral aspect of the deep digital flexor tendon are the most common causes of pain localised to the equine digital flexor tendon sheath. However conventional ultrasonographic techniques provide limited information about acute lesions. Ultrasonographic contrast agents are newly developed materials that have contributed to advancement in human diagnostic imaging. They are currently approved for intravenous use in human and animal models. In this study we described intrathecal use in the horse. This study was undertaken to evaluate the reliability of standard and angle contrast-enhanced ultrasonography to detect and characterize surgically-induced longitudinal lesions in the deep digital flexor tendons.In this pilot study surgically-induced lesions were created in the lateral aspect of the deep digital flexor tendon within the digital flexor tendon sheath in 10 isolated equine limbs to generate a replicable model for naturally occurring lesions. Another 10 specimens were sham operated. All the limbs were examined ultrasonographically before and shortly after the intrasynovial injection of an ultrasound contrast agent containing stabilised microbubbles. The images were blindly evaluated to detect the ability to identify surgically-created lesions. The deep digital flexor tendons were dissected and a series of slices were obtained. The depth of longitudinal defects identified with contrast-enhanced ultrasound scans was compared to the real extent of the lesions measured in the corresponding gross tendon sections.

Results

Contrast-enhanced ultrasonography with both angle and standard approach provided a significant higher proportion of correct diagnoses compared to standard and angle contrast ultrasonography (p < 0.01). Contrast-enhanced ultrasonography reliably estimated the depth of surgically-induced longitudinal lesions in the deep digital flexor tendons.

Conclusion

Contrast-enhanced ultrasound of the digital flexor tendon sheath could be an effective tool to detect intrasynovial longitudinal tears of the deep digital flexor tendon, although an in vivo study is required to confirm these results for naturally occurring lesions.  相似文献   
34.
Rat optic and sciatic nerves were crushed, and 10 minutes to 3 days later nerve segments between the crushed site and the cell body were removed and assayed for posttranslational protein modification by amino acid addition. Protein modification was comparable in intact optic and sciatic nerves, but in sciatic nerves increased to 1.6 times control levels 10 minutes after crushing and reached a maximum of ten times control levels by 2 hours. In optic nerves activity was decreased throughout the time course studied. The results indicate that, in a nerve which is capable of regeneration (sciatic), protein modification by the addition of amino acids increases immediately after injury, but a nerve incapable of regeneration (optic) is incapable of activating the modification reaction. These findings may be important in understanding the reasons for the lack of a regenerative response after injury to central mammalian nerves.  相似文献   
35.
A route for producing semiconducting polymer blends is demonstrated in which a doped pi-conjugated polymer is forced into a three-dimensionally continuous minor phase by the self-assembly of colloidal particles and block copolymers. The resulting cellular morphology can be viewed as a high-internal phase polymeric emulsion. Compared with traditional blending procedures, this process reduces the percolation threshold for electrical conductivity by a factor of 10, increases the conductivity by several orders of magnitude, and simultaneously improves thermal stability. Following this route, new applications can be envisaged for semiconducting polymer blends that require only minimal concentrations of doped pi-conjugated polymer.  相似文献   
36.
37.
The study compares two product strategies—chips versus firewood—and two technological levels—manual versus mechanized—as applied to the thinning of walnut agroforestry plantations, established on ex-arable land. Such plantations are widespread all across Europe, and their establishment was subsidized under the provisions of EU Directive 2080/90, and of regional grant schemes. Field test data were used to build a simple deterministic model for estimating thinning productivity and cost under varying work and economic conditions. This model can assist prospective users when checking the profitability of an operation, or when assessing the competitiveness of alternative options. Removing nurse alder from young walnut plantations yields between 25 and 50 t of fresh biomass per hectare and is crucial to the good development of the stand. The study shows that the removal of nurse alder from walnut plantations is economically viable, and it can also offer some profits if stand and market conditions are favourable. As a rule, the average DBH of removal trees should not be smaller than 12 cm. Best results are obtained with mechanized harvesting, which does not seem to cause heavier stand and soil damage than manual harvesting. Manual harvesting is preferable only if the annual utilization of machinery is very low, and in this case it should be geared to firewood production. The manual whole-tree harvesting (WTH) method used in this study offers the lowest performance under all conditions, and should be replaced with some other manual alternative to WTH. Mechanized WTH offers a significant cost reduction over mechanized short-wood (SWS) harvesting, but this difference is still rather limited: hence, other parameters come into play when deciding what system to apply, and namely product price and mass output. In this respect, one also has to consider the cost of managing the harvesting residue, and that of fertilizing, if soil nutrient depletion is to be feared.  相似文献   
38.
OBJECTIVE: To evaluate the efficacy of tiludronate for the treatment of horses with signs of pain associated with lesions of the thoracolumbar vertebral column. ANIMALS: 29 horses with clinical manifestations of pain associated with lesions of the thoracolumbar vertebral column and abnormal radiographic findings indicative of osteoarthritis of the articular processes-synovial intervertebral joints. PROCEDURES: Horses were initially examined in accordance with a standardized protocol, which included radiographic, ultrasonographic, and scintigraphic examinations. Fifteen horses were randomly assigned to receive tiludronate (1 mg/kg, IV, as a slow-rate infusion), and 14 horses received a control substance (day 0). Horses were monitored for the subsequent 120 days. Clinical evaluations were performed on days 60 and 120. Horses that had no evidence of clinical improvement on day 60 were administered tiludronate. Statistical analyses were performed to compare efficacy at day 60, improvement of dorsal flexibility at day 120, and dorsal flexibility before and 60 days after administration of tiludronate. RESULTS: Horses treated with tiludronate had significant improvement in dorsal flexibility between days 0 and 60, compared with control horses. Clinical improvement in dorsal flexibility was still evident at day 120. The percentage of positive responses was higher in the tiludronate group at 60 days. CONCLUSIONS AND CLINICAL RELEVANCE: Tiludronate had efficacy in the treatment of horses with signs of pain induced by osteoarticular lesions of the thoracolumbar vertebral column, causing a significant improvement in dorsal flexibility. Tiludronate may offer a treatment option for the management of horses with intervertebral lesions and the associated pain.  相似文献   
39.
Starch enzymatic degradation caused by endogenous hydrolases is studied by in situ NMR spectroscopy on a set of hard and soft wheat flours. The results obtained by two different techniques (HR-MAS and (1)H NMR in solution) are analyzed in terms of a Michaelis-Menten kinetic phenomenological model taking into account the presence of endogenous enzymes and their eventual inactivation. The parameters resulting from the best fit of all experimental data to the kinetic model equations are submitted to a multivariate statistical analysis to assess the role of the oligosaccharides release in distinguishing between hard and soft wheats.  相似文献   
40.
Fusapyrone (1) and deoxyfusapyrone (2) are two 3-substituted-4-hydroxy-6-alkyl-2-pyrones isolated from Fusarium semitectum that have considerable antifungal activity against molds. Because of their low zootoxicity and selective action they are potentially utilizable along with biocontrol yeasts for control of postharvest crop diseases. Seven derivatives of 1 (3 and 5-10) and one derivative of 2 (4) were obtained by chemical modifications of the glycosyl residue, the 2-pyrone ring, the aliphatic chain, or a combination thereof, and a structure-activity correlation study was carried out with regard to their zootoxicity and antifungal activity. Derivatives 7-10, as well as 1, were slightly zootoxic in Artemia salina (brine shrimp) bioassays, whereas pentaacetylation of 1 into 3, 5, and 6 resulted in a strong increase in toxicity. Compound 4, the tetraacetyl derivative of 2, was as toxic as 2. Because the structural changes of 1 that resulted in an increase of biological activity in A. salina bioassay were those that affected mainly the water solubility of the molecule, it appears that toxicity is related to hydrophobicity. Compounds 1 and 2 showed strong antifungal activity toward Botrytis cinerea, Aspergillus parasiticus, and Penicilliun brevi-compactum (minimum inhibitory concentration at 24 h = 0.78-6.25 microg/mL). Among derivatives 3-10, only compounds 7, 9, and 10 retained some activity, limited to B. cinerea and at high concentration (25-50 microg/mL). None of the compounds 1-10 inhibited the growth of the biocontrol yeasts Pichia guilliermondii and Rhodotorula glutinis at the highest concentration tested (50 microg/mL).  相似文献   
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