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81.
Rhana Amanda Ribeiro Teodoro Regiane Victória de Barros Fernandes Diego Alvarenga Botrel Soraia Vilela Borges Amanda Umbelina de Souza 《Food and Bioprocess Technology》2014,7(9):2560-2569
This study aimed to characterize rosemary essential oil particles obtained by spray-drying and to evaluate their antimicrobial activity. Measurements of mycelial growth of Penicillium and Aspergillus fungi, isolated from fresh dough, were made applying oil concentrations of 1.0, 5.0, 10.0, 20.0, and 50.0 μL/mL. Fungi and yeast counts in the fresh dough submitted to the control (no oil), pure oil, and microencapsulated oil treatments were also conducted. The microcapsules showed 50 % oil retention after drying, and the major oil components identified were 1,8-cineole (29.0 %), camphor (26.6 %), and α-pinene (10.6 %). The analysis of the particles revealed surfaces without fissures, with a mean particle size of 12.2 μm and presenting an amorphous structure. The growth inhibiting effect of Penicillium sp. fungus, compared to the control, was verified at concentrations of 1.0, 5.0, and 10.0 μL/mL rosemary essential oil, which did not differ among them. For Aspergillus sp., the application of 10.0 μL/mL oil provided greater inhibition compared to 1.0 and 5.0 μL/mL. Complete inhibition occurred with the application of 50.0 μL/mL for both fungal genera tested. At 8 days of dough storage at 25 °C, a decrease of at least 0.7 and 1.5 log cycles of fungal growth was observed in the dough with pure oil and that with microencapsulated oil, respectively, relative to the control. The microencapsulation process retained the antimicrobial property of rosemary essential oil and provided further extension of this activity over time when applied to fresh dough. 相似文献
82.
Elaina M. Tuttle Peter J. Sebastian Amanda L. Posto Helena A. Soini Milos V. Novotny Rusty A. Gonser 《Journal of chemical ecology》2014,40(9):1025-1038
Evidence for the the ability of birds to detect olfactory signals is now well documented, yet it remains unclear whether birds secrete chemicals that can be used as social cues. A potential source of chemical cues in birds is the secretion from the uropygial gland, or preen gland, which is thought to waterproof, maintain, and protect feathers from ectoparasites. However, it is possible that preen oil also may be used for individual recognition, mate choice, and signalling social/sexual status. If preen oil secretions can be used as socio-olfactory signals, we should be able to identify the volatile components that could make the secretions more detectable, determine the seasonality of these secretions, and determine whether olfactory signals differ among relevant social groups. We examined the seasonal differences in volatile compounds of the preen oil of captive white-throated sparrows, Zonotrichia albicollis. This species is polymorphic and has genetically determined morphs that occur in both sexes. Mating is almost exclusively disassortative with respect to morph, suggesting strong mate choice. By sampling the preen oil from captive birds in breeding and non-breeding conditions, we identified candidate chemical signals that varied according to season, sex, morph, and species. Linear alcohols with a 10–18 carbon chains, as well as methyl ketones and carboxylic acids, were the most abundant volatile compounds. Both the variety and abundances of some of these compounds were different between the sexes and morphs, with one morph secreting more volatile compounds in the non-breeding season than the other. In addition, 12 compounds were seasonally elevated in amount, and were secreted in high amounts in males. Finally, we found that preen oil signatures tended to be species-specific, with white-throated sparrows differing from the closely related Junco in the abundances and/or prevalence of at least three compounds. Our data suggest roles for preen oil secretions and avian olfaction in both non-social as well as social interactions. 相似文献
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85.
This paper uses narrative accounts of private gardens in Britain from the Mass-Observation Archive (MO) to explore ideas of landscape, privacy and attachment that emerge from daily practices and routines in these ordinary domestic spaces. We argue for the domestic garden as a vernacular or ordinary landscape that displays tensions between the private and the public nature of home within ambivalent emotional responses. Extended personal narratives offer privileged access to a site of intense engagement and carefully guarded privacy, yet with varying levels of attachment. The garden is a space well described in Britain in its public form but less well known as a private, everyday landscape. In this way a cultural landscape study becomes a contemporary critical geography of an ordinary space. 相似文献
86.
Matthew J. Bauer Catherine S. Snyder Christopher C. Bowland Amanda M. Uhl Maeve A. K. Budi Maria Villancio‐Wolter Henry A. Sodano Jennifer S. Andrew 《Journal of the American Ceramic Society》2016,99(12):3902-3908
Barium titanate nanofibers were uniaxially aligned by electrospinning onto a rotating copper wire drum and alignment was maintained during calcination of the fibers. Two methods for maintaining alignment during calcination were tested, by either using carbon tape or a peeling off method to remove the aligned fibers from the mandrel followed by calcination. The carbon tape removal method led to the formation of shorter aligned nanowires while the peeling off method resulted in longer nanofibers. Additionally, the effects of calcination temperature and time on crystal structure were also examined. The degree of tetragonality in the barium titanate nanofibers increased at higher calcination temperatures and times. Piezoelectricity was confirmed in the nanofibers calcined using piezoeresponse force microscopy, yielding a d33 value of 15.5 pm/V. Using the methods presented here, large quantities of aligned piezoelectric barium titanate and other ceramic fibers or wires can be produced to fulfill their demand in novel microelectronics. 相似文献
87.
Amanda J. Cox Hillary N. Bengtson Dr. Yulia V. Gerasimova Dr. Kyle H. Rohde Dr. Dmitry M. Kolpashchikov 《Chembiochem : a European journal of chemical biology》2016,17(21):2038-2041
Some natural enzymes increase the rate of diffusion‐limited reactions by facilitating substrate flow to their active sites. Inspired by this natural phenomenon, we developed a strategy for efficient substrate delivery to a deoxyribozyme (DZ) catalytic sensor. This resulted in a three‐ to fourfold increase in sensitivity and up to a ninefold improvement in the detection limit. The reported strategy can be used to enhance catalytic efficiency of diffusion‐limited enzymes and to improve sensitivity of enzyme‐based biosensors. 相似文献
88.
Cover Picture: DNA Antenna Tile‐Associated Deoxyribozyme Sensor with Improved Sensitivity (ChemBioChem 21/2016) 下载免费PDF全文
89.
Mallory Batty Rachel Pugh Ilampirai Rathinam Joshua Simmonds Edwin Walker Amanda Forbes Shailendra Anoopkumar-Dukie Catherine M. McDermott Briohny Spencer David Christie Russ Chess-Williams 《International journal of molecular sciences》2016,17(8)
This review evaluates the role of α-adrenoceptor antagonists as a potential treatment of prostate cancer (PCa). Cochrane, Google Scholar and Pubmed were accessed to retrieve sixty-two articles for analysis. In vitro studies demonstrate that doxazosin, prazosin and terazosin (quinazoline α-antagonists) induce apoptosis, decrease cell growth, and proliferation in PC-3, LNCaP and DU-145 cell lines. Similarly, the piperazine based naftopidil induced cell cycle arrest and death in LNCaP-E9 cell lines. In contrast, sulphonamide based tamsulosin did not exhibit these effects. In vivo data was consistent with in vitro findings as the quinazoline based α-antagonists prevented angiogenesis and decreased tumour mass in mice models of PCa. Mechanistically the cytotoxic and antitumor effects of the α-antagonists appear largely independent of α 1-blockade. The proposed targets include: VEGF, EGFR, HER2/Neu, caspase 8/3, topoisomerase 1 and other mitochondrial apoptotic inducing factors. These cytotoxic effects could not be evaluated in human studies as prospective trial data is lacking. However, retrospective studies show a decreased incidence of PCa in males exposed to α-antagonists. As human data evaluating the use of α-antagonists as treatments are lacking; well designed, prospective clinical trials are needed to conclusively demonstrate the anticancer properties of quinazoline based α-antagonists in PCa and other cancers. 相似文献
90.
Governments use incentive programmes to attract new businesses. Due to limited resources, there are questions about which incentives are most effective. Using establishment data from California, and data on the location of disbursements through two federal programmes, we consider the effectiveness of different programmes in attracting new businesses. We find that the amount of funding through the New Markets Tax Credit programme has a significant impact on business activity but find no evidence of an effect from the Community Development Financial Institutions programme. Our results suggest that the effectiveness of these programmes depends on how they provide assistance. 相似文献