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Virgin
Terms modified by Virgin Selected AbstractsSACRED VIRGINS by Lasse HodneART HISTORY, Issue 1 2009Aislinn Loconte No abstract is available for this article. [source] Hunting for the Virgin: Meat, Money, and Memory in Tetiz, YucatánCULTURAL ANTHROPOLOGY, Issue 3 2002Paul K. Eiss First page of article [source] Behavioral evidence for a female-produced sex attractant in Diaphorina citriENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2008Erik J. Wenninger Abstract Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus. It vectors three phloem-restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening disease). Studies were conducted to examine the behavioral responses of male and female D. citri to conspecifics of the same and opposite sex, with and without associated citrus host plants, in both open-air arena choice assays and Y-tube olfactometer assays. Virgin and mated male D. citri colonized citrus plants that were currently or had been previously colonized by virgin or mated female D. citri in greater numbers than control plants without females. However, males or females did not accumulate more on plants colonized by conspecifics of the same sex compared to uninfested plants, and females showed no preference for plants pre-infested with males compared with uninfested controls. In complementary Y-tube olfactometer assays, virgin and mated males chose arms with odor sources from mated females compared with blank controls in the absence of associated citrus host plant volatiles. In both behavioral assays, mated female D. citri appeared more attractive than virgin females. The vibrational calling behavior of male D. citri was reduced when males were challenged by the odors of conspecific mated females relative to when males were challenged by the odor of other males. Collectively, our results provide behavioral evidence for a female-produced volatile sex attractant pheromone in D. citri. Future identification and synthesis of a sex attractant pheromone will be an important contribution to current monitoring and management practices for D. citri. [source] "Shaking Out the Mat": Schism and Organizational Transformation at a Mexican Ark of the VirginJOURNAL FOR THE SCIENTIFIC STUDY OF RELIGION, Issue 2 2003Miguel C. Leatham The apocalyptic Marian colony of Nueva Jerusalén, Mexico suffered a violent schism in 1982, marking a turning point in the history of the sect. The rift resulted in a major organizational transformation and helped to establish the centralized system of authority now observable in the colony. This article examines the ideological and structural factors that promoted the schism. A succession crisis, caused by the death of a Marian apparition seer, precipitated schismatic activity as dissidents struggled to block the charismatic leader's attempts to revise the sect's authority structure and identity. At the same time, the prophet escalated tensions by reframing the conflict as a commitment test. Wallis's theory of structural opportunity for schism is used to show how the conflict grew out of long-standing interest groups and ambiguous authority arrangements in the colony. [source] Thermomechanical properties of virgin and recycled polypropylene impact copolymer/CaCO3 nanocompositesPOLYMER ENGINEERING & SCIENCE, Issue 10 2010A. Elloumi The effect of successive injection moldings on the thermal, rheological, and mechanical properties of a polypropylene impact copolymer (PP) was investigated. The crystal content decreased as the molecular weight decreased due to chain scission with repeated injection molding. The Young modulus and the yield stress remained constant, despite a drop in the strain to break. Virgin and recycled PP matrix were filled with nanosized calcium carbonate (CaCO3) particles. The effect of morphology on the thermal and mechanical properties of nanocomposites of virgin and recycled PP filled with nanosized CaCO3 particles was also studied. The mechanical properties of the nanocomposites were strongly influenced by the intrinsic toughness of the matrix and the concentration and dispersion of the filler. The yield strength and strain of virgin PP decreased gradually, while its Young's modulus increased slightly with increasing CaCO3 loading. These phenomena were less pronounced for the recycled matrix. Incorporation of nanoparticles to virgin matrix produced an increase in tensile stiffness and ductility, when good dispersion of the filler was achieved. However, the impact strength dropped dramatically for high filler contents. A significant increase in impact strength was observed for the recycled PP. POLYM. ENG. SCI., 50:1904,1913, 2010. © 2010 Society of Plastics Engineers [source] Globalization and Its Discontents: Or, What Happens When Two English Misses Meet the Ligurian Peasantry in Annie Hawes's Extra VirginTHE JOURNAL OF POPULAR CULTURE, Issue 2 2007GRACE RUSSO BULLARO First page of article [source] The Many Faces of the VirginANTHROPOLOGY & HUMANISM, Issue 1 2006Douglas Monroy Mary, Mother and Warrior: The Virgin in Spain and the Americas By Linda B. Hall. Austin: The University of Texas Press, 2004. [source] Mexican Conservatives, Clericals, and Soldiers: the ,Traitor' Tomás Mejía through Reform and Empire, 1855,1867BULLETIN OF LATIN AMERICAN RESEARCH, Issue 2 2001Brian Hamnett General Tomás Mejía (1820,67) became a leading Mexican opponent of the Liberal Reform Movement in the mid-nineteenth century. Originating from the Querétaro Sierra Gorda, where for twenty years he had a strong power base, he took his stand in defence of the Catholic religion. A devotee of the local cult of the Virgin of the Pueblito, Mejía cooperated first with the Conservative Party and subsequently with the Second Mexican Empire (1862,67). Beween 1864 and 1866, he became the Empire's principal military commander. Juárez had him shot, along with Maximilian, when the Empire fell. Triumphant Liberals blotted out his name from the history of the nineteenth century. Mejía defended an alternative, Catholic vision of Mexico to the Liberal secular state and its Revolutionary successor. [source] Aemilia Lanyer and the Virgin's Swoon: Theology and Iconography in: Salve Deus Rex JudaeorumENGLISH LITERARY RENAISSANCE, Issue 1 2007Gary Kuchar First page of article [source] Virtually Virgins: Sexual Strategies and Cervical Cancer in Recife, BrazilAMERICAN ANTHROPOLOGIST, Issue 3 2005TELMA CAMARGO DA SILVA No abstract is available for this article. [source] Circadian clock and cell cycle gene expression in mouse mammary epithelial cells and in the developing mouse mammary glandDEVELOPMENTAL DYNAMICS, Issue 1 2006Richard P. Metz Abstract Mouse mammary epithelial cells (HC-11) and mammary tissues were analyzed for developmental changes in circadian clock, cellular proliferation, and differentiation marker genes. Expression of the clock genes Per1 and Bmal1 were elevated in differentiated HC-11 cells, whereas Per2 mRNA levels were higher in undifferentiated cells. This differentiation-dependent profile of clock gene expression was consistent with that observed in mouse mammary glands, as Per1 and Bmal1 mRNA levels were elevated in late pregnant and lactating mammary tissues, whereas Per2 expression was higher in proliferating virgin and early pregnant glands. In both HC-11 cells and mammary glands, elevated Per2 expression was positively correlated with c-Myc and Cyclin D1 mRNA levels, whereas Per1 and Bmal1 expression changed in conjunction with ,- casein mRNA levels. Interestingly, developmental stage had differential effects on rhythms of clock gene expression in the mammary gland. These data suggest that circadian clock genes may play a role in mouse mammary gland development and differentiation. Developmental Dynamics 235:263,271, 2006. © 2005 Wiley-Liss, Inc. [source] Functional morphology of the postpharyngeal gland of queens and workers of the ant Monomorium pharaonis (L.)ACTA ZOOLOGICA, Issue 2 2006Dieter Eelen Abstract Eelen D., Børgesen L.W. and Billen J. 2006. Functional morphology of the postpharyngeal gland of queens and workers of the ant Monomorium pharaonis (L.). ,Acta Zoologica (Stockholm) 87: 101,111 The postpharyngeal gland (PPG) is unique to ants and is the largest exocrine gland in their head. In queens of the pharaoh's ant, Monomorium pharaonis, the gland contains approximately 15 finger-like epithelial extensions on each side and opens dorsolaterally in the posterior pharynx. In these ants the PPG morphology varies considerably according to age and mating status. The epithelial thickness increases with age and reaches a maximum at 3 weeks in both virgin and mated queens. A considerable expansion of the lumen diameter occurs in both groups between 4 and 7 days. Virgin queens release their secretion into the gland lumen from an age of 7 days, whereas mated queens accumulate large amounts of secretion in their epithelium. The increasing epithelial thickness, together with the increasing lumen diameter, the presence of numerous inclusions in the epithelium and the release of secretion, are indicative for increasing gland activity. The gland ultrastructure indicates involvement in lipid metabolism and de novo synthesis of lipids. The PPG of workers consists of 12 finger-like tubes at each side. There is a significant difference in epithelial thickness between nurses and repletes and between nurses and foragers. We suggest the PPG serves different purposes in pharaoh's ants: it is likely that the PPG of workers and virgin queens is used to feed larvae. In mated queens the gland probably plays a role in providing the queen with nutritious oils for egg production. The PPG may also function in signalling species nestmate and caste identity, as well as in the reproductive capacity of the queens. [source] Pseudo-dynamic seismic response of reinforced concrete frames infilled with non-structural brick masonryEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2005F. Colangelo Abstract This paper presents pseudo-dynamic test results on the in-plane seismic behaviour of infilled frames. Thirteen single-storey, single-bay, half-size-scale, reinforced concrete-frame specimens, most of which infilled with non-structural masonry made of perforated bricks and cement mortar are tested. The infills are in contact with frames, without any connector; openings are not covered. The frames are different in their strength and details, reinforcement grade, and aspect ratio. Seismic input is the 1976 Tolmezzo (Friuli, Italy) ground acceleration, to which specimens are subjected two times: virgin and damaged by the previous test. The global seismic response of initially virgin infilled specimens considerably differs from that of bare specimens. This follows a dramatic change of properties: compared to a bare frame, the initial stiffness increases by one order of magnitude, and the peak strength more than doubles. The peak drift lessens; however, the displacement ductility demand does not. The energy demand is greater. Nevertheless, the influence of infill decreases as damage proceeds. Displacement time histories of damaged specimens are quite similar. At the local level, infill causes asymmetry and concentration of the frame deformation. Copyright © 2005 John Wiley & Sons, Ltd. [source] Does constrained oviposition influence offspring sex ratio in the solitary parasitoid wasp Venturia canescens?ECOLOGICAL ENTOMOLOGY, Issue 2 2008MARIE METZGER Abstract 1.,In haplodiploid organisms, virgin or sperm-depleted females can reproduce but are constrained to produce only male progeny. According to Godfray's constrained model, when p, the proportion of females constrained to produce only male progeny, is not null in a panmictic population, unconstrained females should bias their sex allocation towards females to compensate for the excess of males. These unconstrained females should be able to adjust the sex ratio in response to local variation of p. 2.,In this paper an experimental approach is used to test the hypotheses of this model in the solitary endoparasitoid Venturia canescens under both field and laboratory conditions. Specifically, it is tested whether unconstrained females use their encounters with conspecifics (either male or female) to estimate p and then adjust their sex ratio accordingly. 3.,As assumed by Godfray's model, constrained females actively search for host patches in the field and under laboratory conditions produce the same number of offspring during their lifetime as unconstrained females. As predicted by the model, unconstrained females produce a sex ratio biased towards females both in the laboratory and in the field. 4.,The results show that this bias is not a response to encounters with conspecifics previous to oviposition. The hypothesis that the bias is due to differential mortality between sexes during ontogeny is also rejected. The proportions of constrained ovipositions estimated in two natural populations explain only a small fraction of the sex ratio bias observed in V. canescens. [source] Britomart's Armor in Spenser's Faerie Queene: Reopening Cultural Matters of Gender and FigurationENGLISH LITERARY RENAISSANCE, Issue 1 2009Judith H. Anderson In the early cantos of The Faerie Queene, Book III, Britomart is the figure of a young woman vested in armor that forms and masks, expresses and veils, protects and contains her, and she is further invested in finding Artegall, himself a figure vested in various armors. By the beginning of Book IV, Britomart, the armed but nubile virgin, not only Venus-Virgo but also Venus within Mars, has become a complex cultural signifier implicated in cultural conceptions of gender. Her figure indicates that a binaristic conception of gender is inadequate: there are four terms in play or at least two in each of the major amatory players of the books featuring Britomart. Venus-Virgo does not sufficiently represent this doubled perception. Unless seen as a cultural inflection of the composite Venus-Mars, Venus-Virgo conceals the truly Martian, martial, masculine nature of Britomart's figure and elides the hard questions that her armor presents, those involving combinations of nubility and firm resistance, incorporation and active agency, the kinds of questions involving what the early modern period typically perceived as masculinity. My essay explores how a doubled perception of Britomart's gender develops through a process of figuration in allegorical narrative: Britomart is an evolving figure, and her armor conspicuously participates in,figures,the development of her integrity and its loss. [source] Methoprene modulates the effect of diet on male melon fly, Bactrocera cucurbitae, performance at mating aggregationsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2010Ihsan ul Haq Abstract The effect of access to dietary protein (P) (hydrolyzed yeast) and/or treatment with a juvenile hormone analogue, methoprene (M), (in addition to sugar and water) on male aggregation (lekking) behaviour and mating success was studied in a laboratory strain of the melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). Six-day-old males were treated with (1) protein and methoprene (M+P+), (2) only protein (M,P+), or (3) only methoprene (M+P,), and compared with 14-day-old sexually mature untreated males (M,P,). The lekking behaviour of the four groups of males when competing for virgin sexually mature females (14,,16 days old) was observed in field cages. The following parameters were measured at male aggregations: lek initiation, lek participation, males calling, male,male interaction, female acceptance index, and mating success. For all these parameters, the M+P+ males significantly outperformed the other males. Moreover, for all parameters, there was a similar trend with M+P+ > M,P+ > M,P, > M+P,. More M+P+ males called and initiated and participated in lek activities than all other types of male, which resulted in higher mating success. They had also fewer unsuccessful copulation attempts than their counterparts. Whereas treatment with methoprene alone had a negative effect in young males with only access to sugar, access to dietary protein alone significantly improved young male sexual performance; moreover, the provision of methoprene together with protein had a synergistic effect, improving further male performance at leks. The results are of great relevance for enhancing the application of the sterile insect technique (SIT) against this pest species. The fact that access to dietary protein and treatment of sterile males with methoprene improves mating success means that SIT cost-effectiveness is increased, as more released males survive to sexual maturity. [source] Behavioral evidence for a female-produced sex attractant in Diaphorina citriENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2008Erik J. Wenninger Abstract Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus. It vectors three phloem-restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening disease). Studies were conducted to examine the behavioral responses of male and female D. citri to conspecifics of the same and opposite sex, with and without associated citrus host plants, in both open-air arena choice assays and Y-tube olfactometer assays. Virgin and mated male D. citri colonized citrus plants that were currently or had been previously colonized by virgin or mated female D. citri in greater numbers than control plants without females. However, males or females did not accumulate more on plants colonized by conspecifics of the same sex compared to uninfested plants, and females showed no preference for plants pre-infested with males compared with uninfested controls. In complementary Y-tube olfactometer assays, virgin and mated males chose arms with odor sources from mated females compared with blank controls in the absence of associated citrus host plant volatiles. In both behavioral assays, mated female D. citri appeared more attractive than virgin females. The vibrational calling behavior of male D. citri was reduced when males were challenged by the odors of conspecific mated females relative to when males were challenged by the odor of other males. Collectively, our results provide behavioral evidence for a female-produced volatile sex attractant pheromone in D. citri. Future identification and synthesis of a sex attractant pheromone will be an important contribution to current monitoring and management practices for D. citri. [source] Factors influencing the effectiveness of an attracticide formulation against the Oriental fruit moth, Grapholita molestaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2004Maya L. Evenden Abstract An attracticide formulation, LastCallÔOFM, was tested against the Oriental fruit moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae) in replicated small plot field trials in apple, Malus domestica (Borkhausen), orchards in South-eastern Pennsylvania, USA. Attracticide treatments were applied using a calibrated hand pump, and treated plots were compared to similar untreated plots. Male moth activity was monitored using virgin female-baited traps, and the potential for reduction in mating activity was assessed using sentinel virgin females. A comparison of application rates showed that 1500 droplets per ha of the attracticide formulation was as effective as 3000 droplets per ha, and both application rates reduced captures in synthetic pheromone-baited traps for prolonged periods. Droplets placed either at high or low positions within the canopy significantly reduced trap capture and mating with sentinel females. In addition, the only sentinel females that mated in the treated plots were located in the untreated portion of the tree canopy. Mate finding behaviour was equally disrupted by formulations with and without insecticide. Therefore, under the test conditions, the mechanism by which the attracticide formulation worked was by disruption of male orientation, and not by the removal of males due to insecticide poisoning. Two field cage experiments tested the impact of population density on the competitiveness of the attracticide formulation compared to virgin females. A significant proportion of males were captured in female-baited traps at the highest female-to-droplet ratio tested. Equal proportions of males were captured in attracticide-baited traps at male moth densities of 10, 20, 40, and 80 males per cage. These results clarify some of the factors influencing the effectiveness and possible mechanisms of an attracticide management tactic against the Oriental fruit moth. [source] Investment in Mate Guarding May Compensate for Constraints on Ejaculate Production in the Cricket Gryllodes sigillatusETHOLOGY, Issue 12 2001Philip W. Bateman Although there is a corpus of evidence that females of many taxa are choosy about males, there is less information on how males may react to females of different ,quality' (i.e. potential fecundity). The cricket Gryllodes sigillatus shows distinct mate guarding behaviour. We examined how long males mate guard females of different sizes (reflecting egg load and potential fecundity). We also examined the sperm number in ampullae donated to females of different sizes to see if males make a concomitant difference in investment in ejaculate. We also examined mate-guarding behaviour and ejaculate size of males mated to virgin and nonvirgin females of the same size to see if males equate size with increased age and increased likelihood of mating (increased sperm competition). The results showed that males mate guard larger females for longer but make no difference in ejaculate investment between sizes of female. Males make no significant difference in mate guarding investment or ejaculate investment between virgins and nonvirgins of the same size. There is evidence that other species of crickets do alter their ejaculate depending on the female size and mating history, but have less distinct guarding behaviour. We suggest that mate-guarding investment in G. sigillatus may serve a similar function to that of ejaculate investment in other crickets. [source] SEXUAL SELECTION WHEN FERTILIZATION IS NOT GUARANTEEDEVOLUTION, Issue 9 2005Hanna Kokko Abstract Much of the theory of sexual selection assumes that females do not generally experience difficulties getting their eggs fertilized, yet sperm limitation is occasionally documented. How often does male limitation form a selection for female traits that improve their mating rate? The question is difficult to test, because if such traits evolve to be efficient, sperm limitation will no longer appear to be a problem to females. Here, we suggest that changes in choosiness between populations, and in particular between virgin and mated females, offer an efficient way to test this hypothesis. We model the "wallflower effect," that is, changes in female preferences due to time and mortality costs of remaining unmated (for at least some time). We show that these costs cause adaptive reductions of female choice, even if mate encounter rates appear high and females only rarely end their lives unfertilized. We also consider the population consequences of plastic or fixed mate preferences at different mate encounter rates. If mate choice is plastic, we confirm earlier verbal models that virgins should mate relatively indiscriminately, but plastic increase of choosiness in later matings can compensate and intensify sexual selection on the male trait, particularly if there is last male sperm precedence. Plastic populations will cope well with unusual conditions: eagerness of virgins leads to high reproductive output and a relaxation of sexual selection at low population densities. If females lack such plasticity, however, population-wide reproductive output may be severely reduced, whereas sexual selection on male traits remains strong. [source] Temperature-Induced Hydrogels Through Self-Assembly of Cholesterol-Substituted Star PEG- b -PLLA Copolymers: An Injectable Scaffold for Tissue Engineering,ADVANCED FUNCTIONAL MATERIALS, Issue 8 2008Koji Nagahama Abstract Partially cholesterol-substituted 8-arm poly(ethylene glycol)- block -poly(L -lactide) (8-arm PEG- b -PLLA-cholesterol) has been prepared as a novel star-shaped, biodegradable copolymer derivative. The amphiphilic 8-arm PEG- b -PLLA-cholesterol aqueous solution (polymer concentration, above 3,wt%) exhibits instantaneous temperature-induced gelation at 34,°C, but the virgin 8-arm PEG- b -PLLA does not, irrespective of concentration. Moreover, an extracellular matrix (ECM)-like micrometer-scale network structure has been created with favorable porosity for three-dimensional proliferation of cells inside the hydrogel. This network structure is mainly attributed to specific self-assembly between cholesterol groups. The 10 and 20,wt% hydrogels are eroded gradually in phosphate buffered saline at 37,°C over the course of a month, and after that the gel becomes completely dissociated. Moreover, L929 cells encapsulated into the hydrogel are viable and proliferate three-dimensionally inside the hydrogels. Thus, in-vitro cell culture studies demonstrate that 8-arm PEG- b -PLLA-cholesterol is a promising candidate as a novel injectable cellular scaffold. [source] Development in modeling cyclic loading of sands based on kinematic hardeningINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2009Mohammad Maleki Abstract In this paper, there is presented an elastoplastic constitutive model to predict sandy soils behavior under monotonic and cyclic loadings. This model is based on an existing model (Cambou-Jafari-Sidoroff) that takes into account deviatoric and isotropic mechanisms of plasticity. The flow rule used in the deviatoric mechanism is non-associated and a mixed hardening law controls the evolution of the yield surface. In this research the critical state surface and history surface, which separates the virgin and cyclic states in stress space, are defined. Kinematic hardening modulus and stress,dilatancy law for monotonic and cyclic loadings are effectively modified. With taking hardening modulus as a function of deviatoric and volumetric plastic strain and with defining the history surface and stress reversal, the model has the ability to predict the sandy soils' behavior. All of the model parameters have clear physical meanings and can be determined from usual laboratory tests. In order to validate the model, the results of homogeneous tests on Hostun and Toyoura sands are used. The results of validation show a good capability of the proposed model. Copyright © 2009 John Wiley & Sons, Ltd. [source] The structure of the bursa copulatrix in virgin and mated snails, Helisoma duryi (Mollusca): role of acid phosphatase in reproductionINVERTEBRATE BIOLOGY, Issue 1 2001Eric Clelland Abstract. The fine structure of the bursa copulatrix of the virgin snails has been compared with that of mated snails. One of the noticeable changes after mating is an increase in the number of the Golgi and the secretory vesicles. Since some of the vesicles react positively for acid phosphatase it is suggested that this enzyme activity increases following mating. The bursa lumen of the virgin snail contains gel-like materials devoid of spermatozoa, however, following mating, the lumen is full of semen containing live spermatozoa and bacteria. The source of bacteria in the lumen is not known. Acid phosphatase activity is significantly higher in the luminal content of mated snails than in the virgin snails. The activity is higher in the lumen than in the epithelial cells, suggesting that the enzyme is secreted into the lumen where it is utilized for extracellular degradation of spermatozoa. Following mating, the spermatozoa are motile in the lumen of the bursa for ,3,7 d, but become immobile and finally undergo extracellular digestion so that intact spermatozoa are not recognizable by day 10. The use of castrated snails in mating experiments suggest that individuals of Helisoma duryi reproduce by cross fertilization and that the bursa may act as the holding organ from where the spermatozoa are periodically transported to the carrefour over ,7 d. At day 10 following mating, however, autosperms appear in the hermaphroditic duct awaiting the next mating. [source] Religiosity, Self-Control, and Virginity Status in College Students from the "Bible Belt": A Research NoteJOURNAL FOR THE SCIENTIFIC STUDY OF RELIGION, Issue 3 2010Alexander T. Vazsonyi Using a sample of college students (N,= 904) from the "Bible Belt," this study examines the effect of religiosity and self-control on late adolescents' delay in initiating sexual intercourse or oral sex. Findings from logistic regressions provide evidence that for each one unit increase in self-control, the odds of a male remaining a virgin or of delaying oral sex increased by a factor of 1.82 and 2.84, respectively, while for females, the odds of not engaging in oral sex increased by a factor of 1.67. In addition to the effect of self-control, a one unit increase in religiosity results in the odds of a male remaining a virgin by a factor of 3.86 and 3.30, respectively. For females the odds are increased by a factor of 4.13 and 2.60, respectively. Mediation tests also provided evidence that self-control mediated the effects by religiosity on both dependent measures. Thus, both religiosity and self-control independently and additively function as key social control mechanisms that promote late adolescent health. [source] Compatibility study of recycled poly(vinyl chloride)/styrene-acrylonitrile blendsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007David Garcia Abstract The aim of the present study is to analyze the compatibility between recycled Poly(vinyl chloride) (PVC) and styrene-acrylonitrile copolymer (SAN). With this objective recycled PVC coming from credit cards have been blended with both virgin and recycled SAN with the aim of increase the benefits of recycled PVC. The compatibility of the components will be crucial for the final properties of the material. Furthermore, the recycled nature of some of the components will determine the compatibilization capability of the blend. The degradation level in the recycled materials was determined using Fourier transform infrared spectroscopy (FTIR). The compatibility between the PVC and the SAN was studied using differential scanning calorimetry and dynamic mechanical analysis. A greater compatibility was observed in mixtures of PVC and virgin SAN than in mixtures of PVC and recycled SAN. Finally, a morphological study of the fracture surface under cryogenic conditions was carried out using scanning electron microscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source] DNA Extraction from Olive Oil and PCR Amplification of Microsatellite MarkersJOURNAL OF FOOD SCIENCE, Issue 1 2005Raffaele Testolin And ABSTRACT: DNA was extracted from single-cultivar of cold-pressed (virgin) unfiltered and cotton-filtered olive oils that were stored at 4 °C for up to a year using different DNA extraction kits and protocols. DNA was amplified using original and nested primers designed on 6 microsatellites loci of the UDO series. The most consistent results in terms of successful single sequence repeat amplifications were achieved using the Qiagen QIAamp DNA stool extraction kit, slightly modified and applied to oil sample amounts as small as 200 ,L without any pretreatment. The kit allowed getting polymerase chain reaction (PCR) amplicons visible on gel and scorable peaks at the automatic sequencer for all 6 markers analyzed. Less consistent results were achieved with other kits, such as the Promega Wizard Magnetic DNA Purification System for Food, the LB Link-Biotech ExtMan 50,100 Evolution, the Qiagen Plant Mini kit, and the standard cetyltrimethyl-ammonium bromide-based DNA extraction protocol. The integration in the protocols of further tools, such as the hexane-based phase separation, the addition of water or NaCl solutions to the oil, the precipitation and the use of the pellet, and others, did not result in any substantial use. PCR amplifications that gave low DNA yields were improved by adopting the nested PCR technique, which uses the product of the 1st PCR as a template for a 2nd PCR carried out by means of internal primers. Conclusions are drawn as to the applicability of the method to trace the identity of single-cultivar virgin olive oils. Further work is required to check the sensitivity of the method in determining the varietal composition of blended oils, especially in detecting alleles from cultivars present in only small amounts. [source] Effects of selective logging on tree diversity, composition and plant functional type patterns in a Bornean rain forestJOURNAL OF VEGETATION SCIENCE, Issue 1 2003René Verburg Sidiyasa et al. (1999); Anon. (1955,1994) Abstract. The effects of selective logging on tree diversity, changes in tree species composition and plant functional types were studied with the use of seven permanent plots in virgin and in logged forest. All plots were located in a lowland dipterocarp rain forest in East Kalimantan on the island of Borneo. Just after logging and during the following 20 yr tree diversity measured as Fishers', was not significantly affected in logged forest plots. Temporal shifts in tree species composition were analysed with Principal Component Analysis (PCA). Logged forest plots had much larger changes over time than virgin forest plots. In the smallest diameter class, some logged forest plots showed a distinct trajectory in PCA space compared to virgin forest plots, while in larger diameter classes movement of logged plots in PCA space was random. This suggests that there is no predetermined community to which logged forest plots tend to shift when recovering from logging. We found a significant negative correlation between diameter increments and the species-specific wood densities of tree species. Species-specific wood density and potential tree height were used to assign species to five PFTs. As expected, logging increased the fraction of softwood stems in small diameter classes. In the largest diameter classes (, 50 cm DBH) a strong decrease of softwood emergent stems was found in logged forest plots. After more than 20 yr no recruitment was found of softwood emergent stems in selectively logged forest. [source] Effect of Organic Modification on the Compatibilization Efficiency of Clay in an Immiscible Polymer BlendMACROMOLECULAR RAPID COMMUNICATIONS, Issue 20 2005Suprakas Sinha Ray Abstract Summary: This communication describes the effect of organic modifier miscibility with the matrices, and the effect of the initial interlayer spacing of the organoclay, on the overall morphology and properties of an immiscible polycarbonate/poly(methyl methacrylate) blend. By varying the organic-modifier-specific interactions with the blend matrices at the same time as changing the initial interlayer spacing of the organoclay, different levels of compatibilization were revealed. The evidence for the interfacial compatibilization of the organoclay was assessed by scanning electron microscopy observations and was supported by differential scanning calorimetry analyses. The effect on the level of clay exfoliation was also examined. Differential scanning calorimetry scans of virgin, montmorillonite, and various organically modified montmorillonite-compatibilized 40PC/60PMMA blends [source] Behavioural evidence for a female sex pheromone in Cotesia flavipes (Hymenoptera: Braconidae)PHYSIOLOGICAL ENTOMOLOGY, Issue 2 2004Maria Do Rosário T. De Freitas Abstract., The mating behaviour of Cotesia flavipes Cameron, 1891 (Hymenoptera: Braconidae) was observed under laboratory conditions. The results demonstrate that chemical stimuli play an important role in bringing males and females together for mating. Females from this species release chemical compounds to attract males, which exhibit a distinct courtship behaviour divided into three main steps: (i) antennation, (ii) lateral bouncing and (iii) wing fluttering. Ethological tests using hexane extracts from two different parts of the female's body (head plus thorax and abdomen) demonstrate that males are more attracted and also display a courtship behaviour when a filter paper containing hexane extracts from the abdomen is presented to them, indicating that the abdomen is the source of the sex pheromone of this species. Naive males of this species respond to hexane extracts of this gland by displaying courtship behaviour. Furthermore, additional tests show that C. flavipes females mate only once, whereas virgin males do not show any preference for virgin or mated females, suggesting that mated females of this species continue to produce sex attractants after mating. [source] Effect of temperature on hygroscopic thickness swelling rate of composites from lignocellolusic fillers and HDPEPOLYMER COMPOSITES, Issue 11 2009Abdollah Najafi Effect of temperature on hygroscopic thickness swelling rate of lignocellolusic fillers/HDPE (high density polyethylene) composites was investigated. The composites were manufactured using a dry blend/hot press method. In this method, powder of plastic and dried powder of lignocellolusic material were mixed in high-speed mixer and then the mixed powder were pressed at 190°C. Lignocellolusic fillers/HDPE composites panels were made from virgin and recycled HDPE (as plastic) and wood sawdust and flour of rice hull (as filler) at 60% by weight filler loadings. Nominal density and dimensions of the panels were 1 g/cm3 and 35 × 35 × 1 cm3, respectively. Thickness swelling rate of manufactured wood plastic composites (WPCs) were evaluated by immersing them in water at 20, 40, and 60°C for reaching a certain value where no more thickness was swelled. A swelling model developed by Shi and Gardner [Compos. A, 37, 1276 (2006)] was used to study the thickness swelling process of WPCs, from which the parameter, swelling rate parameter, can be used to quantify the swelling rate. The results indicated that temperature has a significant effect on the swelling rate. The swelling rate increased as the temperature increased. The swelling model provided a good predictor of the hygroscopic swelling process of WPCs immersed in water at various temperatures. From the activation energy values calculated from the Arrhenius plots, the temperature had less effect on the thickness swelling rate for the composites including wood sawdust compared with the rice hull as filler and the composites including recycled compared with the virgin HDPE as plastic. 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