Volatile compounds from the mite Acarus siro L. in food

The headspace above two strains of Acarus siro maintained on wheat germ/bran has been shown to contain the hydrocarbons, decane, undecane and tridecane together with the furanoid terpene, perillen. When the bodies of the separated mites were extracted with diethyl ether a new compound was found in addition to those in the headspace. This compound has been identified as 2-hydroxy-6-methyl benzaldehyde. None of these compounds appears to be responsible for the ‘minty’ smell reportedly related to mite infestation.     

Validity, predictive efficiency, and practical significance of selection tests.

The acceptance of validity coefficients at face value as measures of practical significance is evaluated by examining each functional relationship between 3 indexes of predictive efficiency r, r2, and E and 3 measures of practical significance the increase of the criterion mean, the expected proportion "satisfactory," and the expected proportion in 10 criterion categories. The validity coefficient, r is a linear function of the increase of the criterion mean and very nearly a linear function of the other 2 measures of practical significance; r2 and E are related to these 3 measures in a more curvilinear manner. A table is presented that gives the proportion expected in each of 18 criterion categories as a function of r and the selection ratio. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Survey of shell egg processing plant sanitation programs: effects on non-egg-contact surfaces

To successfully implement a hazard analysis critical control point plan, prerequisite programs are essential. Sanitation standard operating procedures are an important part of such a plan and can reduce contamination levels so that food safety and quality are not adversely affected. Noncontact surfaces in the shell egg processing plants can serve as a reservoir of cross-contamination. The objective of this study was to assess the efficacy of sanitation programs used in a variety of shell egg processing facilities (in-line, off-line, and mixed operations). Fourteen different noncontact surfaces were sampled in nine commercial facilities across the southeastern United States. Non-egg-contact surfaces were defined as those where the shell egg does not come into direct contact with the surface or with the fluid from that surface. Gauze pads soaked in sterile phosphate-buffered saline were used for sampling at the end of a processing day (POST) and again the next morning prior to operations (PRE). Aerobic plate counts (APCs) and numbers of Enterobacteriaceae were determined. No significant differences (P > 0.05) were found between POST and PRE counts for either population recovered from the 14 sampling sites. Only samples from the floor under the farm belts, nest-run loader, washers, and packer heads were reduced by 1 log CFU/ml of rinsate for APCs or Enterobacteriaceae counts. APCs of more than 10(4) CFU/ml of rinsate were recovered from many samples. Highest APCs were found on the floor under the farm belt and on shelves of the nest-run carts. High APCs were found on the wheel surface for off-line carts and on the loading dock floor. Highest Enterobacteriaceae counts were found in samples from the floor, drain, and nest-run egg cart shelves. A lack of significant difference between POST and PRE counts indicates that current sanitation programs could be improved. These data suggest that traffic patterns for the movement of eggs and materials through the plant should be reevaluated so that cross-contamination is reduced.     

Effectiveness of a laboratory-scale vertical tower static chamber steam pasteurization unit against Escherichia coli O157:H7, Salmonella typhimurium, and Listeria innocua on prerigor beef tissue

A laboratory-scale vertical tower steam pasteurization unit was evaluated to determine the antimicrobial effectiveness of different exposure times (0, 3, 6, 12, and 15 s) and steam chamber temperatures (82.2, 87.8, 93.3, and 98.9 degrees C) against pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria innocua) inoculated onto prerigor beef tissue. Samples were collected and microbiologically analyzed immediately before and after steam treatment to quantify the effectiveness of each time-temperature combination. The 0-s exposure at all chamber temperatures (cold water spray only, no steam treatment) was the experimental control and provided < or = 0.3 log CFU/cm2 reductions. Chamber temperatures of 82.2 and 87.8 degrees C were ineffective (P > 0.05) at all exposure times. At 93.3 degrees C, significant reductions (> 1.0 log CFU/cm2) were observed at exposure times of > or = 6 s, with 15 s providing approximately 1 log cycle greater reductions than 12 s of exposure. The 98.9 degrees C treatment was consistently the most effective, with exposure times of > or = 9 s resulting in >3.5 log CFU/cm2 reductions for all pathogens.     

First- and second-order information in natural images: a filter-based approach to image statistics

Previous analyses of natural image statistics have dealt mainly with their Fourier power spectra. Here we explore image statistics by examining responses to biologically motivated filters that are spatially localized and respond to first-order (luminance-defined) and second-order (contrast- or texture-defined) characteristics. We compare the distribution of natural image responses across filter parameters for first- and second-order information. We find that second-order information in natural scenes shows the same self-similarity previously described for first-order information but has substantially less orientational anisotropy. The magnitudes of the two kinds of information, as well as their mutual unsigned correlation, are much stronger for particular combinations of filter parameters in natural images but not in unstructured fractal images having the same power spectra.     

Tutorial on the biology of nanotopography

The aims of this short tutorial are fourfold: 1) to introduce readers unfamiliar with the field to major concepts in the field; 2) to inform the reader of major unresolved questions; 3) to inform readers of a few major sources of relevant literature; and 4) to place the subject in relation to its relevance to other areas of science and practical application.     

Grip force vectors for varying handle diameters and hand sizes

Grip force was measured along two orthogonal axes and vector summed. Sixty-one participants recruited from a manufacturing facility (29 men and 32 women) grasped instrumented cylinders (2.54, 3.81, 5.08, 6.35, and 7.62 cm diameter) using a maximal voluntary power grip. Two orthogonal force measurements relative to the third metacarpal were resolved into a magnitude and corresponding angle. On average, magnitude increased 34.8 N as handle diameter increased from 2.54 cm to 3.81 cm, and then monotonically declined 103.8 N as the handle diameter increased to 7.62 cm. The average direction monotonically decreased from 59.2 degrees to 37.7 degrees as handle diameter decreased from the largest to the smallest. When the diameter was smallest, the greatest force component, Fx (168.6 N), was in the direction where the fingertips opposed the palm. Conversely, when the diameter was largest, the smallest component, Fx (77.7 N), was in the same direction. These values are averaged for the left and right hand. The angle for the largest diameter increased with increasing hand size. These relationships should be useful for the design of handles that require gripping in specific directions, such as for hand tools and controls. Actual or potential applications of this research include the design of handles that require gripping in specific directions, such as for hand tools and controls, that reduce effort, and that prevent fatigue and overexertion.     

Fetal MEG redistribution by projection operators

The fetal magnetoencephalogram (fMEG) is measured in the presence of large interference from the maternal and fetal magnetocardiograms. This interference can be efficiently attenuated by orthogonal projection of the corresponding spatial vectors. However, the projection operators redistribute the fMEG signal among sensors. Although redistribution can be readily accounted for in the forward solution, visual interpretation of the fMEG signal topography is made difficult. We have devised a general, model-independent method for correction of the redistribution effect that utilizes the assumption that we know in which channels the fMEG should be negligible (such channels are distant from the known fetal head position). In a simplified case where the fMEG can be explained by equivalent current dipoles, the correction can also be obtained from fitting the dipoles to the fMEG signal. The corrected fMEG signal topography then corresponds to the dipole forward solution, but without orthogonal projection. We illustrate the redistribution correction on an example of experimentally measured flash evoked fMEG.