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991.
Soini HA Linville SU Wiesler D Posto AL Williams DR Novotny MV 《Journal of chemical ecology》2012,38(2):145-156
We investigated head- and cheek-rubbing behavior in four species of large felines, lions (Leo panther), leopards (Panthera pardus), tigers (Panthera tigris), and cougars (Puma concolor), in captivity. Preliminary behavioral observations found that lions and tigers, but not leopards and cougars, showed behavioral
responses to cardboard rubbing samples from head and cheek areas from conspecific felines, compared to the blank cardboard
controls. In this context, surface samples on the facial areas of each species were collected to analyze volatile organic
compounds that could be involved in the facial marking of felines. Previously developed stir bar surface sampling methodology
was used. From all cheek and forehead samples, 100 volatile organic compounds were identified or tentatively identified. Among
these, 41 have been previously reported to be present in feline urine and marking secretions. Several new compounds were identified
on facial surfaces. Some of the compounds showed substantial quantitative differences among the species. One compound, that
has not been reported previously in mammals, 3-acetamidofuran, was found in all investigated species. It was synthesized and
tested for behavioral responses. No responses were elicited in a preliminary test. Future research will test other potential
signaling compounds and their mixtures for ability to elicit behavioral responses. 相似文献
992.
Mozar Naing Dallas Webster Nolan Blue Rick Hudgens Zahir Parkar Sumeer Bhatara Pankaj Gupta Donald Y. C. Lie 《Journal of Electronic Testing》2012,28(5):723-731
High volume production environments create great challenges for production testing and verification of Radio Frequency (RF) devices. In this environment, much emphasis is put on parallel testing, or the ability to test multiple devices at the same time using a single tester. In order for this parallelism to become a reality, there is a need for production RF tests to be simplified and reduced to requiring only the simplest test stimulus and analysis. In this paper, we present a new method of measuring the performance of a Frequency Modulation (FM) receiver that requires only a continuous wave signal input in order to eliminate the more costly Signal-to-Noise Ratio test. Using this new technique we will then demonstrate how simplifying this test and adding frequency diversity enables testing of up to 8 devices in parallel using a single tester. 相似文献
993.
PurposeTo examine the role of elevated corneal temperature in the development of rubbing/massage-related corneal deformation and the possibility that warm compresses in the management of meibomian gland dysfunction or chalazion could contribute to such adverse responses.MethodsWith reference to reports of corneal deformation associated with meibomian gland dysfunction, chalazion, dacryocystoceles and post-trabeculectomy, the mechanisms for increased corneal temperature due to ocular massage, especially when combined with warm compresses are examined.ResultsSeveral mechanisms for rubbing/massage to elevate corneal temperature have been described, apart from the application of warm compresses or other forms of heat.ConclusionsRaised corneal temperature helps to explain corneal deformation which develops in association with rubbing or massage in conditions such as keratoconus, chalazion, post-trabeculectomy, post-laser assisted in situ keratomileusis, post-graft and dacryocystoceles. When combined with warm compresses or other methods of heat delivery to the eye, the elevation of corneal temperature appears to explain how meibomian gland dysfunction treatment involving warm compresses and massage could induce rubbing-related deformation. Patients whose management involves iatrogenic ocular massage appear to require screening for risk of corneal deformation. Risk may be increased for patients with a concurrent habit of rubbing their eyes abnormally in response to allergic itch for example. It appears to be possible to modify ocular massage techniques to reduce the risk of corneal deformation. Careful tutoring and follow-up using corneal topography appears to be required when massage is prescribed, especially when used in conjunction with heat application. 相似文献
994.
Barry Stidder Jean‐Pierre Alcaraz Lavinia Liguori Nawel Khalef Aziz Bakri Erik B. Watkins Philippe Cinquin Donald K. Martin 《Advanced functional materials》2012,22(20):4259-4267
A simple way to form an interpenetrating hydrogel (IPH) by combining a layer‐by‐layer polyelectrolyte membrane with agarose is reported. The formed IPH membrane is more robust and easily manipulated compared to a polyelectrolyte membrane with the same number of layers. The IPH has good diffusion characteristics and retains the advantageous surface charge from the polyectrolyte composition that facilitates the adsorption of a stable lipid bilayer. The stable adsorption of a lipid bilayer on the IPH creates a biomimetic membrane system that is optimized for utilization in a diffusion chamber. 相似文献
995.
Mattick K Durham K Domingue G Jørgensen F Sen M Schaffner DW Humphrey T 《International journal of food microbiology》2003,85(3):213-226
In this study, the survival of Salmonella, Campylobacter and Escherichia coli O157: H7, when exposed to a range of constant temperatures (47-60 degrees C), in hard or soft water, in the presence/absence of detergent (0-0.3%) and organic matter, and during drying, was investigated. Further experiments used a washing-up process simulation, where soiled dishes contaminated with bacteria were washed in a bowl of warm water containing detergent. In addition, this study considered the risk of bacterial transfer onto (1) sterile dishes and sponges via contaminated water, (2) kitchen surfaces wiped with a contaminated sponge, (3) items placed in direct contact with a contaminated kitchen surface, (4) food placed on a contaminated dish or (5) dishes from contaminated food. A proportion of dishes remained contaminated with all pathogen types after a typical washing-up. Water hardness did not appear to affect survival. E. coli, and to a lesser extent Salmonella, survived towel- or air-drying on dishes and after towel-drying the cloth became contaminated on every occasion, regardless of the test organism. A proportion of sterile dishes washed after contaminated dishes became contaminated with pathogens but transfer from dishes onto food was rare. Washing-up sponges frequently became contaminated with pathogens. The results of this study highlight the potential for survival and cross contamination of food borne pathogens in the kitchen environment. 相似文献
996.
Listeria monocytogenes ATCC 19111 cultivated in nutrient-rich medium (brain heart infusion, BHI) or starved in minimal medium (10% filter sterilized pond water and 90% sterilized distilled water) were investigated for their initial attachment to austenitic stainless steel No. 4 with satin finish at 4 °C, 20 °C, 30 °C, 37 °C, or 42 °C. A droplet (10 μl) containing 107 CFU/ml of L. monocytogenes suspended in BHI or minimal medium was placed on the stainless steel surface. After holding in saturated humidity for 3 h at the desired temperature the surface was washed and prepared for scanning electron microscopy (SEM). Using SEM, attachment of L. monocytogenes was determined by counting cells remaining on the surface. When L. monocytogenes cultivated in BHI were used, with the exception of the number of attached cells being lower at 42 °C than at 37 °C and 30 °C, the number of attached cells increased with increasing temperature (P < 0.05). When L. monocytogenes starved in minimal medium were used, the number of attached cells also increased with increasing attachment temperature (P < 0.05), but the number of attached cells at 42 °C was lower than that at the other temperatures. The attachment of L. monocytogenes to stainless steel surface was greater when cultivated in rich medium of BHI vs starved in the minimal medium. 相似文献
997.
Iron(VI) and iron(V) oxidation of thiocyanate 总被引:1,自引:0,他引:1
Sharma VK Burnett CR O'Connor DB Cabelli D 《Environmental science & technology》2002,36(19):4182-4186
Thiocyanate (SCN-) is used in many industrial processes and is commonly found in industrial and mining waste-waters. The removal of SCN- is required because of its toxic effects. The oxidation of thiocyanate (SCN-) by environmentally friendly oxidants, Fe(VI) and Fe(V), has been studied anaerobically using stopped-flow and premix pulse radiolysis techniques. The stoichiometry with Fe(VI) was determined to be 4HFeO(4-) + SCN(-) + 5H2O-->4Fe(OH)3 + SO4(2-) + CNO(-) + O2 + 2OH-. The rate law for the oxidation of SCN- by Fe(VI) was found to be -d[Fe(VI)]/dt = k11([H+]/([H+] + Ka,HFeO4)) [Fe(VI)][SCN-] where k11 = 2.04 +/- 0.04 x 10(3) M-1 s-1 and pKa,HFeO4 = 7.33. A mechanism is proposed that agrees with the observed reaction stoichiometry and rate law. The rate of oxidation of SCN- by Fe(V) was approximately 3 orders of magnitude faster than Fe(VI). The higher reactivity of Fe(V) with SCN- indicates that oxidations by Fe(VI) may be enhanced in the presence of appropriate one-electron-reducing agents. The results suggest that the effective removal of SCN- can be achieved by Fe(VI) and Fe(V). 相似文献
998.
999.
A random-walk model of visual discrimination is described and applied to reaction time (RT) distributions from three discrete-trial experiments with pigeons. Experiment 1 was a two-choice hue discrimination task with multiple hues. Choice percentages changed with hue discriminability; RTs were shortest for the least and most discriminable stimuli. Experiments 2 and 3 used go/no-go hue discriminations. Blocks of sessions differed in reward probability associated with a variable red stimulus in Experiment 2 and with a constant green stimulus in Experiment 3. Changes in hue had a large effect on response percentage and a small effect on RT; changes in reward shifted RT distributions on the time axis. The “random-walk, pigeon” model applied to these data is closely related to Ratcliff's diffusion model (Ratcliff, 1978; Ratcliff & Rouder, 1998). Simulations showed that stimulus discriminability affected the speed with which evidence accumulated toward a response threshold, in line with comparable effects in human subjects. Reward probability affected bias, modeled as the amount of evidence needed to reach one threshold rather than the other. The effects of reward probability are novel, and their isolation from stimulus effects within the decision process can guide development of a broader model of discrimination. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
1000.
Lynam Donald R.; Gaughan Eric T.; Miller Joshua D.; Miller Drew J.; Mullins-Sweatt Stephanie; Widiger Thomas A. 《Canadian Metallurgical Quarterly》2011,23(1):108
A new self-report assessment of the basic traits of psychopathy was developed with a general trait model of personality (five-factor model [FFM]) as a framework. Scales were written to assess maladaptive variants of the 18 FFM traits that are robustly related to psychopathy across a variety of perspectives including empirical correlations, expert ratings, and translations of extant assessments. Across 3 independent undergraduate samples (N = 210–354), the Elemental Psychopathy Assessment (EPA) scales proved to be internally consistent and unidimensional, and were strongly related to the original FFM scales from which they were derived (mean convergent r = .66). The EPA scales also demonstrated substantial incremental validity in the prediction of existing psychopathy measures over their FFM counterparts. When summed to form a psychopathy total score, the EPA was substantially correlated with 3 commonly used psychopathy measures (mean r = .81). Finally, in a small male forensic sample (N = 70), the EPA was significantly correlated with scores on a widely used self-report psychopathy measure, disciplinary infractions, alcohol use, and antisocial behavior. The EPA provides an opportunity to examine psychopathy and its nomological network through smaller, more basic units of personality rather than by scales or factors that blend these elements. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献