How much is the workload of surgeons in Scandinavia?

According to figures presented at the Bianniul General Meeting of the Scandinavian Surgical Society, the mean number of operations performed per surgeon at some clinics of different sizes in Denmark, Finland, Iceland, Norway and Sweden ranged from 90 to 240 in 1996. This corresponds to 2.6 to 8.5 hours actual operating time, though figures are misleading since time spent assisting at operations, or on endoscopies, minor diagnostics and outpatient procedures, and essential pre- and post-operative tasks is not included. This level of operative activity is considered barely sufficient for training surgeons or for maintaining surgical skills. Surgeons could devote more time to surgery if a greater proportion of their non-surgical workload was taken over by other hospital staff, which would also reduce the number of surgeons required.     

Intrasectoral homogeneity and the accuracy of multisectoral models

In regional science, there is a class of linear, multisectoral models whose solutions were first found as the summation of a power expansion series. Regional input-output models, Garin-Lowry models and Markov chain models represent familiar examples. Each begins with a partitioning of system state space into discrete sectors. Each generates sector-specific multipliers. Accurate estimation of multipliers depends, in part, upon the degree of homogeneity within system state space sectors. This paper's first objective is to explore the effects intrasectoral heterogeneity on multipliers used in a Markov model of residential vacancy chains. Its second objective is to develop a method for defining internally homogeneous sectors. Our data is a linked 1975-'80-'85 file on housing and population in Gävle, Sweden. It is used to calibrate vacancy chain models with crude and refined sectoral definitions. Matrix algebra is used to find the effects of sectoral definitions on vacancy chain lengths. Long-linear analysis is used to measure the contribution of sectoral refinements to overall data variation. A two-stage, nested clustering strategy is used to define homogeneous sectors for two time periods. Finally questions are advanced about the stability of sectoral definitions, multisectoral relationships, and the dynamics of sectoral formation.     

Freeze–thaw stability of mayonnaise type oil-in-water emulsions

In this paper, the freeze–thaw stability of mayonnaise type oil-in-water emulsions is studied. The emphasis of the experiments have been on the properties of the dispersed oil phase as only small, or no effects, were observed from initial experiments on changing the properties of the aqueous phase within the investigated ranges. Different vegetable oils are investigated in order to relate the composition of the oil phase to the stability of the corresponding emulsion. The crystallization behaviour of the oils is studied with differential scanning calorimetry (DSC) and by freeze–thaw experiments in bulk systems. The amounts of triacylglycerides in the oils that theoretically crystallize at different temperatures are also calculated. Moreover, the impact of the freezing rate on the stability of emulsions is investigated. Large differences in freeze–thaw stability of emulsion prepared with different oils are observed. By principal component analysis (PCA) the stability of the emulsion could be correlated with the composition and crystallization behaviour of the oils. Small/no effects of the addition of different substances (for example polyglycerol esters and trehalose) to both oil and water phase are observed. Moreover, the experiments on the freezing conditions show that alteration of the freezing rate have a large impact on the freeze–thaw stability.     

Thermal and Irradiation Creep Behavior of a Titanium Aluminide in Advanced Nuclear Plant Environments

Titanium aluminides are well-accepted elevated temperature materials. In conventional applications, their poor oxidation resistance limits the maximum operating temperature. Advanced reactors operate in nonoxidizing environments. This could enlarge the applicability of these materials to higher temperatures. The behavior of a cast gamma-alpha-2 TiAl was investigated under thermal and irradiation conditions. Irradiation creep was studied in beam using helium implantation. Dog-bone samples of dimensions 10 × 2 × 0.2 mm³ were investigated in a temperature range of 300 °C to 500 °C under irradiation, and significant creep strains were detected. At temperatures above 500 °C, thermal creep becomes the predominant mechanism. Thermal creep was investigated at temperatures up to 900 °C without irradiation with samples of the same geometry. The results are compared with other materials considered for advanced fission applications. These are a ferritic oxide-dispersion-strengthened material (PM2000) and the nickel-base superalloy IN617. A better thermal creep behavior than IN617 was found in the entire temperature range. Up to 900 °C, the expected 10⁴ hour stress rupture properties exceeded even those of the ODS alloy. The irradiation creep performance of the titanium aluminide was comparable with the ODS steels. For IN617, no irradiation creep experiments were performed due to the expected low irradiation resistance (swelling, helium embrittlement) of nickel-base alloys.     

Short communication: effect of alley floor cleanliness on free-stall and udder hygiene

The objective was to evaluate the effect of alley floor cleanliness on the hygiene of the free-stalls and udder and teats of cows. Mechanical scrapers were used on rubber-slatted floors to improve the cleanliness of the alley floor. Two sections containing 21 cows each were evaluated once weekly for a period of 3 wk. One section had scrapers on the rubber-slatted floor in the alleys and the other section did not. The scrapers ran 12 and 7 times/d in the free-stall alley and feed alley, respectively. Manure accumulation in the alleys at approximately 2 h after the scrapers had run was less in the section with the scraper than in that without the scraper. Differences between sections with and without scrapers were found in the sites close to the wall in the feed alley, and immediately behind the free-stalls in the free-stall alley. In the section without scrapers, manure accumulation was greater in the free-stall alley than in the feed alley. Manure contamination of the area in the free-stalls where the udder normally comes in contact with the free-stall floor was significantly reduced from 29.1 to 17.9 ± 2.4 g of dry matter when the alley floor was kept clean by the use of scrapers. The hygiene scores of the dirtiness of udders were reduced from 25.8 ± 1.7 to 18.9 ± 1.6, and those of the teats from 37.9 ± 2.3 to 24.2 ± 2.3 in the section with scrapers and cleaner alley floor compared with the section without scrapers. The scrapers greatly improved the hygiene on the rubber-slatted alley floor. The cleaner alley floor had a positive effect on the cleanliness of the free-stalls and the udder and teats of the cows.     

Learning to detect misaligned point clouds

Matching and merging overlapping point clouds is a common procedure in many applications, including mobile robotics, three‐dimensional mapping, and object visualization. However, fully automatic point‐cloud matching, without manual verification, is still not possible because no matching algorithms exist today that can provide any certain methods for detecting misaligned point clouds. In this article, we make a comparative evaluation of geometric consistency methods for classifying aligned and nonaligned point‐cloud pairs. We also propose a method that combines the results of the evaluated methods to further improve the classification of the point clouds. We compare a range of methods on two data sets from different environments related to mobile robotics and mapping. The results show that methods based on a Normal Distributions Transform representation of the point clouds perform best under the circumstances presented herein.     

An attributional analysis of reactions to stigmas.

In two experiments, we examined the perceived controllability and stability of the causes of 10 stigmas. Guided by attribution theory, we also ascertained the affective reactions of pity and anger, helping judgments, and the efficacy of five intervention techniques. In the first study we found that physically based stigmas were perceived as onset-uncontrollable, and elicited pity, no anger, and judgments to help. On the other hand, mental-behavioral stigmas were perceived as onset-controllable, and elicited little pity, much anger, and judgments to neglect. In addition, physically based stigmas were perceived as stable, or irreversible, whereas mental-behavioral stigmas were generally considered unstable, or reversible. The perceived efficacy of disparate interventions was guided in part by beliefs about stigma stability. In the second study we manipulated perceptions of causal controllability. Attributional shifts resulted in changes in affective responses and behavioral judgments. However, attributional alteration was not equally possible for all the stigmas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synthesis of some divalent O- and S-glycosides of galabiose and globotriose

Derivatives of galabiose (alpha-D-Galp-(1-->4)-D-Galp) and globotriose (a-D-Galp-(1-->4)-beta-D-Galp-(1-->4)-D-Glcp) were coupled to various 1,2- and 1,3-dihydroxymethyl- and dimercapto-methylbenzenes to give the corresponding divalent glycosides, potentially useful as inhibitors of bacterial adhesion.     

Filter-response line shapes of resonant waveguide gratings

The line shape symmetry properties of planar dielectric resonant waveguide-grating filters are theoretically characterized for both TE and TM polarization. Classical antireflection theory is applied to the design of guided-mode resonance filters and it is shown that the symmetry of the line-shape response is determined by the location of the resonance relative to the minimum of the antireflection band. The conditions that allow a single dielectric layer to simultaneously function as both a waveguide grating and as an antireflection thin film are presented. Single-layer antireflection waveguide gratings are shown to yield highly symmetrical filter-response line shapes with suppressed sideband reflectivity and 100% reflectivity at the resonance wavelength. The parametric locations of the symmetrical line-shape responses are predicted approximately by solving the resonance-location equation with the grating thickness set equal to a multiple of a half-resonance-wavelength. Graphical representations of these solutions are provided. Symmetric waveguide-grating filters are shown to yield symmetrical line shapes with near-zero sideband reflectivity, whereas asymmetric filters produce symmetrical line shapes but suffer from increased sideband reflectance that increases as the asymmetry of the filter grows. Numerous calculated examples are presented to demonstrate that ideal reflection filters can be designed by combining thin-film antireflection effects and resonance effects in a single dielectric layer