999 resultados para BG Lure


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Here we fabricate and characterise bioactive composite scaffolds for bone tissue engineering applications. 45S5 Bioglass® (45S5) or strontium-substituted bioactive glass (SrBG) were incorporated into polycaprolactone (PCL) and fabricated into 3D bioactive composite scaffolds utilising additive manufacturing technology. We show that composite scaffolds (PCL/45S5 and PCL/SrBG) can be reproducibly manufactured with a scaffold morphology highly resembling that of PCL scaffolds. Additionally, micro-CT analysis reveals BG particles were homogeneously distributed throughout the scaffolds. Mechanical data suggested that PCL/45S5 and PCL/SrBG composite scaffolds have higher compressive Young’s modulus compared to PCL scaffolds at similar porosity (~75%). After 1 day in accelerated degradation conditions using 5M NaOH, PCL/SrBG, PCL/45S5 and PCL lost 48.6 ±3.8%, 12.1 ±1% and 1.6 ±1% of its original mass, respectively. In vitro studies were conducted using MC3T3 cells under normal and osteogenic conditions. All scaffolds were shown to be non-cytotoxic, and supported cell attachment and proliferation. Our results also indicate that the inclusion of bioactive glass (BG) promotes precipitation of calcium phosphate on the scaffold surfaces which leads to earlier cell differentiation and matrix mineralisation when compared to PCL scaffolds. However, as indicated by ALP activity, no significant difference in osteoblast differentiation was found between PCL/45S5 and PCL/SrBG scaffolds. These results suggest that PCL/45S5 and PCL/SrBG composite scaffold shows potential as a next generation bone scaffold.

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In male tephritid fruit flies of the genus Bactrocera, feeding on secondary plant compounds (sensu lato male lures = methyl eugenol, raspberry ketone and zingerone) increases male mating success. Ingested male lures alter the male pheromonal blend, normally making it more attractive to females and this is considered the primary mechanism for the enhanced mating success. However, the male lures raspberry ketone and zingerone are known, across a diverse range of other organisms, to be involved in increasing energy metabolism. If this also occurs in Bactrocera, then this may represent an additional benefit to males as courtship is metabolically expensive and lure feeding may increase a fly's short-term energy. We tested this hypothesis by performing comparative RNA-seq analysis between zingerone-fed and unfed males of Bactrocera tryoni. We also carried out behavioural assays with zingerone- and cuelure-fed males to test whether they became more active. RNA-seq analysis revealed, in zingerone-fed flies, up-regulation of 3183 genes with homologues transcripts to those known to regulate intermale aggression, pheromone synthesis, mating and accessory gland proteins, along with significant enrichment of several energy metabolic pathways and gene ontology terms. Behavioural assays show significant increases in locomotor activity, weight reduction and successful mating after mounting; all direct/indirect measures of increased activity. These results suggest that feeding on lures leads to complex physiological changes, which result in more competitive males. These results do not negate the pheromone effect, but do strongly suggest that the phytochemical-induced sexual selection is governed by both female preference and male competitive mechanisms.

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In Australian cinema since the mid-2000s, horror has become a popular and at times commercially viable genre for low-budget and emerging filmmakers targeting international markets. While the annual horror film output of Australia pales in comparison to that of other Anglophone nations like the United States, Great Britain, and Canada, it has produced several significant titles that have performed moderately well at the international box office, from Wolf Creek (Greg McLean, 2005) to Daybreakers (Michael and Peter Spierig, 2009). Yet as part of a broader tradition of Anglophone horror cinema, many Australian horror movies have been heavily influenced by US and to a lesser extent British horror films. Furthermore, Australian horror film production is largely an internationally-oriented sector that relies on its relationships with overseas distributors and often investors. Consequently, the content and style of Australian horror movies have regularly been tailored for international markets. As a direct consequence some filmmakers have sought to trade on the “Australianness” of their product, others have attempted to pass off their films as faux-American, while others still have attempted to develop placeless films effaced of national reference points. This chapter examines local production as part of a broader tradition of Anglophone horror cinema, the influence of US horror movies, and the limitations of the domestic marketplace. The article concludes with an analysis of how the lure of the US market influences Australian filmmakers’ textual strategies.

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In tephritid fruit flies of the genus Bactrocera Macquart, a group of plant derived compounds (sensu amplo ‘male lures') enhance the mating success of males that have consumed them. For flies responding to the male lure methyl eugenol, this is due to the accumulation of chemicals derived from the male lure in the male rectal gland (site of pheromone synthesis) and the subsequent release of an attractive pheromone. Cuelure, raspberry ketone and zingerone are a second, related group of male lures to which many Bactrocera species respond. Raspberry ketone and cuelure are both known to accumulate in the rectal gland of males as raspberry ketone, but it is not known if the emitted male pheromone is subsequently altered in complexity or is more attractive to females. Using Bactrocera tryoni as our test insect, and cuelure and zingerone as our test chemicals, we assess: (i) lure accumulation in the rectal gland; (ii) if the lures are released exclusively in association with the male pheromone; and (iii) if the pheromone of lure-fed males is more attractive to females than the pheromone of lure-unfed males. As previously documented, we found cuelure was stored in its hydroxyl form of raspberry ketone, while zingerone was stored largely in an unaltered state. Small but consistent amounts of raspberry ketone and β-(4-hydroxy-3-methoxyphenyl)-propionic acid were also detected in zingerone-fed flies. Males released the ingested lures or their analogues, along with endogenous pheromone chemicals, only during the dusk courtship period. More females responded to squashed rectal glands extracted from flies fed on cuelure than to glands from control flies, while more females responded to the pheromone of calling cuelure-fed males than to control males. The response to zingerone treatments in both cases was not different from the control. The results show that male B. tryoni release ingested lures as part of their pheromone blend and, at least for cuelure, this attracts more females.

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Phytochemical lures such as methyl eugenol (ME) and cue-lure are used in the management of Bactrocera fruit flies for monitoring and control. These lures are not just attractants, but also trigger physiological changes in males that lead to enhanced mating success. Additionally, in the cue-lure-responsive Bactrocera tryoni, females mated with lure-fed males exhibit changes in fecundity, remating receptivity and longevity. While the lures show current generation effects, no research has been carried out on possible multigenerational effects, although such effects have been hypothesized within a ‘sexy-son’ sexual selection model. In this study, we test for indirect, cross-generational effects of lure exposure in F1offspring of B. tryoni females mated with cue-lure-fed, zingerone-fed and lure-unfed (=control) males. The F1 attributes we recorded were immature development time, immature survival, adult survival and adult male lure foraging. No significant differences were found between treatments for any of the three life-history measurements, except that the offspring sired by zingerone-fed males had a longer egg development time than cue-lure and control offspring. However, indirect exposure to lures significantly enhanced the lure-foraging ability of F1 adult males. More offspring of cue-lure-fed males arrived at a lure source in both large flight cages and small laboratory cages over a 2-h period than did control males. The offspring of zingerone-fed males were generally intermediate between cue-lure and control offspring. This study provides the first evidence of a next generation effect of fruit fly male lures. While the results of this study support a ‘sexy-son’ sexual selection mechanism for the evolution of lure response in Bactrocera fruit flies, our discussion urges caution in interpreting our results in this way.

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Online dating and romance scams continue to lure in Australians with figures this week showing people have lost more than A$23 million this year alone, with average individual losses at A$21,000 – three times higher than other types of fraud. The Australian Competition and Consumer Commission (ACCC) set up the Scam Disruption Project in August to help target those it believes have been caught in such scams. Over three months it sent 1,500 letters to potential victims in New South Wales and the Australian Capital Territory. The figures released this week show that 50 people have been scammed, losing a total A$1.7 million – that’s an average of A$34,000 per victim. Almost three quarters of the scams were dating and romance related, which saw it evolve into the number one category of fraud victimisation. Romance scams continue to pose a problem – despite the efforts of the police and ACCC – so why is it that people continue to fall for them?

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Poisoned protein baits comprise a recognized method for controlling tephritid fruit flies in the form of a ‘lure-and-kill’ technique. However, little is known about how a fly's internal protein and carbohydrate levels (i.e. nutritional status) might influence the efficacy of this control. In the present study, the relationships between the internal levels of protein (as measured by total body nitrogen) and carbohydrate (as measured by total body carbon) of the fruit fly Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) are investigated, as well as its foraging behaviours in response to protein, fruit and cue-lure (a male-specific attractant) baits. Small cage behavioural experiments are conducted using flies from cultures of different nutritional status and wild flies sampled from the field during the fruiting cycle of a guava crop. For female flies, increasing total body nitrogen is correlated with decreased protein foraging and increased oviposition activity; increasing total body carbon levels generate the same behavioural changes except that the oviposition response is not significant. For males, there are no significant correlations between changes in total body nitrogen and total body carbon and protein or cue-lure foraging. For wild flies from the guava orchard, almost all of them are sexually mature when entering the crop and, over the entire season, total body nitrogen and total body carbon levels are such that protein hunger is unlikely for most flies. The results infer strongly that the requirements of wild, sexually mature flies for protein are minimal and that flies can readily gain sufficient nutrients from wild sources for their physiological needs. The results offer a mechanistic explanation for the poor response of male and mature female fruit flies to protein bait spray.

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Lithium silicophosphate glasses have been prepared by a sol-gel route over a wide range of compositions. Their structural and electrical properties have been investigated. Infrared spectroscopic studies show the presence of hydroxyl groups attached to Si and P. MAS NMR investigations provide evidence for the presence of different phosphatic units in the structure. The variations of de conductivities at 423 K and activation energies have been studied as a function of composition, and both exhibit an increasing trend with the ratio of nonbridging oxygen to bridging oxygen in the structure. Ac conductivity behavior shows that the power law exponent, s, is temperature dependent and exhibits a minimum. Relaxation behavior has been examined in detail using an electrical modulus formalism, and modulus data were fitted to Kohlraush-William-Watts stretched exponential function. A structural model has been proposed and the unusual properties exhibited by this unique system of glasses have been rationalized using this model. Ion transport in these glasses appears to be confined to unidimensional conduits defined by modified phosphate chains and interspersed with unmodified silica units.

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We studied the microstructural evolution of multiple layers of elastically stiff films embedded in an elastically soft matrix using a phase field model. The coherent and planar film/matrix interfaces are rendered unstable by the elastic stresses due to a lattice parameter mismatch between the film and matrix phases, resulting in the break-up of the films into particles. With an increasing volume fraction of the stiff phase, the elastic interactions between neighbouring layers lead to: (i) interlayer correlations from an early stage; (ii) a longer wavelength for the maximally growing wave; and therefore (iii) a delayed break-LIP. Further, they promote a crossover in the mode of instability from a predominantly anti-symmetric (in phase) one to a symmetric (out of phase) one. We have computed a stability diagram for the most probable mode of break-up in terms of elastic modulus Mismatch and Volume fraction. We rationalize our results in terms of the initial driving force for destabilization, and corroborate our conclusions using simulations in elastically anisotropic systems.

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Russian Karelians were one of the small peasant nations of the Russian Empire that began to identify themselves as nations during the late imperial period. At that historical moment Russian Karelia fell between an economically undeveloped empire and the rapidly modernizing borderland of Finland. The economic and cultural lure of Finland drew Karelians into the Finnish camp. This attraction was seen as a challenge to Russia and influenced the straggle between Russia and Finland for the Karelians. This struggle was waged from 1905 to 1917. This work is focused on the beginning stage of the struggle, its various phases, and their results. The confrontation extended into different dimensions (economic, political, ideological, church and cultural politics) and occurred on two levels: central and regional. Countermeasures against local nationalisms developed much earlier both in Russia and in other empires for use were also used in the Russian Karelian case. Economic policies were deployed to try to make relations with Russia more alluring for Karelians and to improve their economic condition. However, these efforts produced only minimal results due to the economic weakness of the empire and a lack of finances. Fear of the economic integration of the Karelians and Finns, which would have stimulated the economy of the Karelia, also hindered these attempts. The further development of the Orthodox Church, the schools and the zemstvos in Karelia yielded fewer results than expected due to the economic underdevelopment of the region and the avoidance of the Finnish language. Policizing measures were the most successfull, as all activities in Russian Karelia by the Finns were entirely halted in practice. However, the aspiration of Russian Karelians to integrate their home districts with Finland remained a latent force that just waited for an opportunity to push to the surface again. Such a chance materialized with the Russian revolution. The Karelian question was also a part of Russian domestic political confrontation. At the and of the 1800s, the Russian nationalist right had grown strong and increasingly gained the favor of the autocracy. The right political forces exploited the Karelian question in its anti-Finnish ideology and in its general resistance to the national emancipation of the minority peoples of Russia. A separate ideology was developed, focusing on the closeness of Karelians to the "great Russian people." Simultaneously, this concept found a place in the ultramonarchist myth of the particularly close connection between the people and tsar that was prominent in the era of Nicholas II. This myth assigned the Karelians a place amongst the "simple people" faithful to the tsar.

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Orchard experiments were conducted in southern New South Wales to evaluate the efficacy of multispecies pheromone lures in trapping two economically important species of Carpophilus. Captures of Carpophilus davidsoni Dobson and Carpophilus mutilatus Erichson in traps baited with aggregation pheromones of both species or a three-way lure that also included the pheromone of Carpophilus hemipterus (L.) were not significantly different from captures in traps baited with conspecific pheromones. Carpophilus davidsoni and C. mutilatus were cross-attracted to traps baited with the pheromone of the other species, but numbers were significantly reduced compared with traps baited with conspecific or heterospecific pheromones. Multispecies lures will improve prospects for the commercial use of synthetic aggregation pheromones in Carpophilus beetle management in stone-fruit orchards.

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Headspace analysis and solvent extraction of the pollenbearing flower spike of Spathiphyllum cannaefolium have been conducted by GC-MS, to determine the basis of the flower spike’s attractancy to certain fruit-fly species. The major components were benzyl acetate, methyleugenol, methylchavicol, p-methoxybenzyl acetate and fatty acids. Benzyl acetate is known to be attractive to D. cueurbitae, D. dorsalis and C. capitata (representing the three different ‘male-lure categories’) and methyleugenol (one of these male-lures) attracts D. cacuminatus, D. dorsalis and D. occipitalis. Thus the odoriferous flowerspike exhibits wide ranging attractancy and hence Spathiphyllum cannaefolium may have some application as a fruit-fly control measure for small orchards where ‘methyleugenol-attracted’ species (e.g. D. cacuminatus, D. dorsalis, D. occipitalis) are the dominant pests.

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My PhD-thesis The uneasy borders of desire Magnus Enckell's representations of masculinities and femininities and the question how to create the self concentrates on the works of Finnish fin-de-siècle artist Magnus Enckell (1870-1925). My thesis deals with representations of masculinities, femininities, sexualities and different identity-positions. My research is about questions concerning representational ways of melancholy, androgyny, narcissism, themes of Golden Age and Double in Enckell s ouvre. These themes are analyzed by contextualizing them with different, but intersecting, discourses of varied scientific, artistic and occult ideas in the fin-de-siècle. The main point is analyze how the subject is constructed in both Foucauldian and Freudian sense and what one has to know about oneself. My approaches are based on ideas expressed in different discourses as queer-theory, Michel Foucault s genealogical epistemology and knowledge-power theory, psychoanalysis, art history and visual culture studies. My starting point lays is Foucault s idea expressed in his The History of Sexuality that the constitution of homosexual or as well as heterosexual subject inaugurates possibilities for transgressive activities e.g. by giving own voice to the sexualized subject. My main thesis is to suggest that Enckell s works in their multiple and ambiguous ways construct a phantasmatic position for viewer who may identify oneself to different desires, may construct or deconstruct a sexual identity for oneself or try to define the truth about oneself. Enckell s works should be considered as a contradictory processes which both seduce person to construct an identity and as well as lure person to pursue for the deconstruction of specific and permanent identity by celebrating the ambiguousness and discontinuity in one s identity. I m suggesting that the gazing subject feels pleasure in finding one s identity but the one must face the exposure of the melancholic structure which forms the basis of sexual desire. The subject may try to resolve one s melancholy by creating a phantasy about the original and unisexual being where desires, sexualities, phantasies and identities haven t been diverged. This can be fantasized in terms of art which forms a double for the melancholic subject who is in this limited and imaginary way able to forget for a while one s existential solitude.

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There are several areas in the plywood industry where Operations Research techniques have greatly assisted in better decision-making. These have resulted in improved profits, reduction of wood losses and better utilization of resources. Realizing these, some of the plywood manufacturing firms in the developed countries have established separate Operations Research departments or divisions. In the face of limited raw-material resources, raising costs and a competitive environment, the benefits attributable to the use of these techniques are becoming more and more significant.

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Resistivity behaviour of PbO---PbX2 (X=F,Cl) glasses has been investigated as a function of pressure at laboratory temperature. All PbO---PbX2 glasses undergo crystallization under pressure and the resistivities of crystallized samples are lower than the corresponding glasses. Transitions in PbO---PbF2 glasses exhibit a first order behaviour while transitions in PbO---PbCl2 glasses possess features of a continuous transition. The differences in the pressure behaviour of the two glass systems have been attributed to the differences in the ionic sizes of F− and Cl− ions and also to pressure induced modifications of Pb---O bonding.