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81.
Bozena Jemiolo David J. Gubernick M. Catherine Yoder Milos Novotny 《Journal of chemical ecology》1994,20(10):2489-2500
The urinary profiles of adult female and male California mice were examined to determine the volatile compounds that may affect reproduction. The urinary volatiles identified by gas chromatography-mass spectrometry (GC-MS) include ketones, pyrazines, alkanes, nitrile, and aldehyde. None of volatile compounds was specific to males or females. The concentration of urinary volatiles in pregnant and lactating females was significantly higher than in virgin females. Male urinary volatile concentrations were similar to those of pregnant and lactating females. The GC profiles of both sexes were distinguished by a high percentage (36%) of pyrazine derivatives that were also in unusually high concentrations. These compounds may play a wide-ranging role in the control of reproduction in the California mouse. 相似文献
82.
Julia Jezierska Henryk Kozlowski Bozena N. Kolarz Andrzej Trochimczuk 《Polymer Bulletin》1991,26(2):231-235
Summary E. p. r. and absorption spectra were used to indicate the formation of the complexes between copper (II) ions and acrylic resins containing oligoamines bound via amide bonds to acrylate units. The number of bound nitrogen atoms depends on the length of the amine chain attached to acrylamide unit. 相似文献
83.
Multiple fault analog circuit testing by sensitivity analysis 总被引:1,自引:0,他引:1
Analog circuit testing is considered to be a very difficult task. This difficulty is mainly due to the lack of fault models and accessibility to internal nodes. To overcome this problem, an approach is presented for analog circuit modeling and testing. The circuit modeling is based on first-order sensitivity computation. The testability of the circuit is analyzed by the multiple-fault model and by functional testing. Component deviations are deduced by measuring a number of output parameters, and through sensitivity analysis and tolerance computation. Using this approach, adequate tests are identified for testing catastrophic and soft faults. Some experimental results are presented for simple models as well as multiple-fault models. 相似文献
84.
Understanding the dynamical response to the applied electric and heat field is crucial in pyroelectric applications of polymers, although their heterogeneity on molecular and crystalline level and the nonuniform distribution of electric charge make it complex. We studied the effect of dielectric heterogeneity induced during electric polarization in uniaxially and biaxially oriented PVDF films. Both pyroelectric and dielectric response of PVDF poled in low dc field and corona-charged was measured over a wide frequency range. We find that heterogeneity on the crystalline level is responsible for the piling up of the field-induced electric charges which causes an increase in the relaxation time ascribed to the relaxation process in the MHz range. It is also concluded that the dielectric heterogeneity in is important only in the case when the front electrode of the pyroelectric sensor is that which was grounded during dc poling 相似文献
85.
Michal Lech Bozena Kostek Andrzej Czyzewski 《Journal of Intelligent Information Systems》2016,46(3):531-562
Ranking of search results and ads has traditionally been studied separately. The probability ranking principle is commonly used to rank the search results while the ranking based on expected profits is commonly used for paid placement of ads. These rankings try to maximize the expected utilities based on the user click models. Recent empirical analysis on search engine logs suggests unified click models for both ranked ads and search results (documents). These new models consider parameters of (i) probability of the user abandoning browsing results (ii) perceived relevance of result snippets. However, current document and ad ranking methods do not consider these parameters. In this paper we propose a generalized ranking function—namely Click Efficiency (CE)—for documents and ads based on empirically proven user click models. The ranking considers parameters (i) and (ii) above, optimal and has the same time complexity as sorting. Furthermore, the CE ranking exploits the commonality of click models, hence is applicable for both documents and ads. We examine the reduced forms of CE ranking based upon different underlying assumptions, enumerating a hierarchy of ranking functions. Interestingly, some of the rankings in the hierarchy are currently used ad and document ranking functions; while others suggest new rankings. Thus, this hierarchy illustrates the relationships between different rankings, and clarifies the underlying assumptions. While optimality of ranking is sufficient for document ranking, applying CE ranking to ad auctions requires an appropriate pricing mechanism. We incorporate a second price based mechanism with the proposed ranking. Our analysis proves several desirable properties including revenue dominance over Vickrey Clarke Groves (VCG) for the same bid vector and existence of a Nash equilibrium in pure strategies. The equilibrium is socially optimal, and revenue equivalent to the truthful VCG equilibrium. As a result of its generality, the auction mechanism and the equilibrium reduces to the current mechanisms including Generalized Second Price Auction (GSP) and corresponding equilibria. Furthermore, we relax the independence assumption in CE ranking and analyze the diversity ranking problem. We show that optimal diversity ranking is NP-Hard in general, and a constant time approximation algorithm is not likely. Finally our simulations to quantify the amount of increase in different utility functions conform to the results, and suggest potentially significant increase in utilities. 相似文献
86.
The aim of this article is to investigate whether separating music tracks at the pre-processing phase and extending feature vector by parameters related to the specific musical instruments that are characteristic for the given musical genre allow for efficient automatic musical genre classification in case of database containing thousands of music excerpts and a dozen of genres. Results of extensive experiments show that the approach proposed for music genre classification is promising. Overall, conglomerating parameters derived from both an original audio and a mixture of separated tracks improve classification effectiveness measures, demonstrating that the proposed feature vector and the Support Vector Machine (SVM) with Co-training mechanism are applicable to a large dataset. 相似文献
87.
A commercial platinum (Pt) catalyst with 0.15% platinum ingredient (referred to as Pt-O) was investigated for activity in the combustion of chlororganic compounds, for resistance to poisoning, and for potential application to control gas emissions. Investigations were also carried out on six other catalysts. These were platinum catalysts with platinum contents varying from 0.05% to 0.15% and platinum catalysts with palladium or manganese as active ingredients. The catalysts were tested in the oxidation of a chlorobenzene-xylene mixture to determine their poisoning resistance. The presence of manganese was found to have a disadvantageous influence on the combustion of chlororganics. 相似文献
88.
Schulz Richard; Czaja Sara J.; Lustig Amy; Zdaniuk Bozena; Martire Lynn M.; Perdomo Dolores 《Canadian Metallurgical Quarterly》2009,54(1):1
Objective: To assess the efficacy of two psychosocial interventions for caregivers of older persons with spinal cord injury (SCI). Design: A multisite, three-group, randomized controlled trial comparing two active intervention conditions with each other and to an information-only control group. One hundred seventy-three caregiver and care-recipient dyads were randomly assigned to one of three conditions: a caregiver-only treatment condition in which caregivers received a multicomponent intervention based on their risk profile; a dual-target condition in which the caregiver intervention was complemented by a treatment targeting the care recipient, designed to address both caregiver and care recipient risk factors; and an information-only control condition in which the caregiver received standard printed information about caregiving, SCI, and aging. Outcome Measures: A multivariate outcome comprised of six indicators linked to the goals of the interventions was the primary outcome of the study. The multivariate outcome included measures of depressive symptoms, burden, social support and integration, self-care problems, and physical health symptoms. Results: At 12 months, caregivers in the dual-target condition had improved quality of life as measured by our multivariate outcome when compared to the control condition. Using the dyad as the unit of analysis, the dual-target condition was superior to both the control condition and the caregiver-only condition in our multivariate outcomes analysis. Dyads enrolled in the dual-target condition had significantly fewer health symptoms than control condition and caregiver-only condition participants and were less depressed when compared to participants in the caregiver-only condition. In follow-up analyses we found that a higher proportion of caregivers in the dual-target condition had clinically significant improvements in depression, burden, and health symptoms when compared with the caregiver-only condition. Conclusion: Caregivers are in need of and can benefit from interventions that help them manage the medical and functional limitations of the care recipient. Intervention strategies that target both the caregiver and care recipient are particularly promising strategies for improving the quality of life of caregivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
Ewa Schab‐Balcerzak Mariola Siwy Bozena Jarzabek Anna Kozanecka‐Szmigiel Krzysztof Switkowski Bronisław Pura 《应用聚合物科学杂志》2011,120(2):631-643
This paper reports novel photoresponsive, processable poly(esterimide)s functionalized with the azobenzene and tricyanovinylene groups. Post and prepolymerization strategies were utilized for preparation of the new photochromic polymers with imide rings. The postpolymerization method of azopolymer synthesis included a functionalization of precursor poly(esterimide) containing dialkylaminophenyl groups with diazonium salt of aniline. The precursor poly(esterimide) was obtained from synthesized 2,2′[N‐phenylethyloaniline‐di(4‐estro‐1,2‐dicarboxylic)]anhydride and 4,4′‐methylene bis(2,6‐dimethylaniline). The prepolymerization strategy based on polycondesation of 2,4‐diaminoazobenzene with two dianhydrides, that is, with or without the azobenzene group. The new dianhydride with azobenzene unit was obtained. The reaction of post‐tricyanovinylation was carried out for substitution of prepared polymers with tricyanovinylene groups. The synthesized polymers were characterized and evaluated by FTIR, 1H NMR, X‐ray, UV‐Vis spectroscopies, and DSC. The polymers exhibited glass transition temperatures in the range of 119–208°C and good solubilities in common organic solvents, providing optical‐quality films. Thermal stability of the polymers films was investigated by UV‐Vis spectroscopy. Preliminary investigations of the optical anisotropy in chosen poly(esterimide)s were carried out by photoinduced birefringence measurements. Relatively high photoinduced birefringence (Δn = 0.01) was measured for polyimide with covalently bonded azobenzene substituted with strong acceptor group. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
90.
Magdalena Senderowicz Teresa Nowak Hanna Weiss-Schneeweiss Laszlo Papp Bozena Kolano 《International journal of molecular sciences》2022,23(7)
Although Crepis was the first model plant group in which chromosomal changes were considered to play an important role in speciation, their chromosome structure and evolution have been barely investigated using molecular cytogenetic methods. The aim of the study was to provide a better understanding of the patterns and directions of Crepis chromosome evolution, using comparative analyses of rDNA loci number and localisation. The chromosome base number and chromosomal organisation of 5S and 35S rDNA loci were analysed in the phylogenetic background for 39 species of Crepis, which represent the evolutionary lineages of Crepis sensu stricto and Lagoseris, including Lapsana communis. The phylogenetic relationships among all the species were inferred from nrITS and newly obtained 5S rDNA NTS sequences. Despite high variations in rDNA loci chromosomal organisation, most species had a chromosome with both rDNA loci within the same (usually short) chromosomal arm. The comparative analyses revealed several independent rDNA loci number gains and loci repositioning that accompanied diversification and speciation in Crepis. Some of the changes in rDNA loci patterns were reconstructed for the same evolutionary lineages as descending dysploidy. 相似文献