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161.
The objective of the present study was to evaluate the interrelationship between the cuticular and postpharyngeal glands' hydrocarbons, both in the individual ant and during its interaction with nestmates. In vivo radiochemical assays were employed to monitor the de novo hydrocarbon biosynthesis from acetate in the ant's body. The newly synthesized hydrocarbons appeared first internally and after 24 hr they accumulated in the postpharyngeal gland and on the cuticular surface. Blocking the possibility of external transfer of hydrocarbons between cuticle and postpharyngeal gland led to a significant decrease of labeled hydrocarbons in the postpharyngeal gland. In addition, during encounters between labeled and unlabeled ants, newly synthesized hydrocarbons were transferred, mainly via trophallaxis, but also by allo-grooming and physical contact. In view of these results, we propose as a model for their dynamics that hydrocarbons are synthesized in tissues associated with the integument. Through self-grooming, there is a constant exchange of hydrocarbons between the cuticular surface and the postpharyngeal gland. Furthermore, in encounters between nestmates, hydrocarbons are exchanged among them mostly by trophallaxis, with the mediation of the postpharyngeal gland. Thus, this gland acts as a pool for mixing colonial hydrocarbons and may serve to attain a unified colony odor. 相似文献
162.
M. Ángeles Pozo-Bayón Inmaculada Andújar-Ortiz M. Victoria Moreno-Arribas 《Food research international (Ottawa, Ont.)》2009,42(7):754-761
In recent years the use of inactive dry yeast (IDY) preparations such as inactive yeast, yeast autolysates, yeast extracts and yeast hulls or walls have been widely used within the oenological industry to improve either technological processes or the sensory characteristics of wines. Some of these preparations have very specific applications and there are currently many of these products in the market under different brands that promise different ways of improving wine characteristics. Nevertheless, scientific information about the chemistry beyond their use and their action mode is still scarce.The objective of this review is to revise the different applications of specific IDY preparations in winemaking, on the basis of their action mechanisms taking into consideration the scientific information available, underlining the necessity of more scientific work in order to better characterize their chemical composition, their action mechanisms, and the establishment of better criteria for their oenological use. 相似文献
163.
Victoria Fernández Azahara Díaz Álvaro Blanco Jesús Val 《Journal of the science of food and agriculture》2009,89(13):2323-2330
BACKGROUND: A strategy to supply Ca directly to fruits as a tool for improving peach quality has been devised and tested under field conditions. Since peaches in the area of study (Calanda, Spain) are routinely bagged shortly after thinning, a method based on the application of Ca gels to the fruit surface was introduced. The effect of surface treatments was assessed in terms of quality, nutrient balance and surface deposition. RESULTS: Application of Ca‐containing formulations increased mesocarp and exocarp Ca concentrations, providing evidence for the penetration of Ca through the peach skin. Surface Ca treatments had a particular mode of deposition and in some instances improved the shelf life of fruits without affecting their quality. CONCLUSION: Surface treatment with Ca‐containing gels appears to be a viable approach to increase fruit Ca, quality and storability of bagged peach cultivars and should be optimised in future studies. Copyright © 2009 Society of Chemical Industry 相似文献
164.
165.
Juraj Doupovec Ilja Thurzo Drahoslav Barančok Victoria P. Shilo 《Materials Research Bulletin》1977,12(2):119-125
When cooling a melt the cooling rate in different layers varies due to differences in heat transfer. These changes in cooling rate were determined experimentally for the As2S3 melt in a quartz ampoule with diameter of 17 mm. The cooling rate at air quenching varies from 1.36 K/s in the bulk middle to 2.11 K/s in the border layers, and from 3.54 to 38.80 K/s for water quenching, respectively. Further, the corresponding changes in the density, microhardness, glass-transition temperature and electrical conductivity in dependence on the choice of the measured sample from various parts of the bulk were found. The anomalous behaviour of these parameters in dependence on the cooling rate corresponds to the polymeric structure of the glass. 相似文献
166.
Carver Charles S.; Pozo Christina; Harris Suzanne D.; Noriega Victoria; Scheier Michael F.; Robinson David S.; Ketcham Alfred S.; Moffat Frederick L. Jr.; Clark Kimberley C. 《Canadian Metallurgical Quarterly》1993,65(2):375
At diagnosis, 59 breast cancer patients reported on their overall optimism about life; 1 day presurgery, 10 days postsurgery, and at 3-, 6-, and 12-mo follow-ups, they reported their recent coping responses and distress levels. Optimism related inversely to distress at each point, even controlling for prior distress. Acceptance, positive reframing, and use of religion were the most common coping reactions; denial and behavioral disengagement were the least common reactions. Acceptance and the use of humor prospectively predicted lower distress; denial and disengagement predicted more distress. Path analyses suggested that several coping reactions played mediating roles in the effect of optimism on distress. Discussion centers on the role of various coping reactions in the process of adjustment, the mechanisms by which dispositional optimism vs pessimism appears to operate, third variable issues, and applied implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
167.
G Acciari J C Eckroad L F Fajardo R Mu?oz R de Mercado A Pradilla G Quintero B de Ramíez F Victoria D H Wilson 《Archivos latinoamericanos de nutrición》1977,27(3):359-375
The main objective of this work is to determine what anthropometric method to use under field conditions, given the kind of mainutrition to be detected. In the first part of the work some criteria and procedures are given by which to compare the field perfomance characteristics (i.e. transportability, facility of use, etc.), of the most commonly used instruments. Then we extrapolate these characteristics to the respective methods like weight for age, weight for height, height for age, etc. In the second part we present a correlation matrix among the various methods and analyze it in order to associate with each method a specific typology of malnutrition. 相似文献
168.
Examined imitative recall for sentences conforming to the grammatical rules of standard English vs those suggested for nonstandard (black) English. Ss were a total of 87 black and 51 white low- and middle-income children in Grades 3 and 4. Low-income blacks showed better recall than middle-income whites for nonstandard sentences and poorer recall for standard sentences. School integration influenced the performance of low-income blacks: Those who had attended an integrated school were both better on standard and poorer on nonstandard sentences than those who had attended a segregated school. For middle-income Ss, both black and white, there were no evident linguistic effects of integration. Although dialect clearly affected recall, results do not support a conception of black dialect as a separate linguistic system with totally consistent rules. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
169.
A national survey of 1,000 psychologists, to which 223 responded, assessed professionals' clinical practices and beliefs about the treatment of adult survivors of childhood sexual abuse (CSA), personal CSA history, and the phenomenon of clients remembering CSA in therapy. Results indicated that over 25% of therapists reported using guided imagery, dream interpretation, bibliotherapy regarding sexual abuse, referral to sexual abuse survivors' group, and free association of childhood memories as memory retrieval techniques with clients who had no specific memory of CSA. However, the majority of therapists reported that they had not seen any cases of adult clients entering therapy with no memory of CSA and subsequently recalling abuse in the course of therapy. A personal history of CSA was not associated with most clinical practices related to treating sexual abuse survivors. The implications for training and establishing scientific standards of psychological practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
170.
Stoddard Victoria M.; Tsushima William T.; Heiby Elaine 《Canadian Metallurgical Quarterly》1988,25(3):370
Studied data from 194 adult outpatients in a private medical center to determine whether the Minnesota Multiphasic Personality Inventory (MMPI) or a utilization prediction scale (UPS) predicted decrease in outpatient medical utilization following psychotherapy. Although none of the 13 MMPI scales discriminated differences, a UPS cutoff score correctly categorized 75% of the original sample. When the UPS was applied to a cross-validation sample, two-thirds were correctly identified. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献