Boar taint in very small organic entire male pigs - preliminary results

Very small entire male pigs can be part of a new concept of organic seasonal production of pigs. The concept includes outdoor production of small entire male pigs, very large female pigs and sows slaughtered after first litter. The entire males and the sows are slaughtered in the summer and the female pigs gilts in December. The purpose of the very small entire male pigs is to avoid castration and boar taint at the same time. In order to make the concept special regarding product quality and image, different crossbreeds are considered including a traditional Danish breed. Two seasons (2007 and 2008) are planned. Results of the 2007 season are presented

Higher-harmonic adaptation and the detection of squarewave gratings

Adaptation to a high contrast sinewave grating of 1 c/deg spatial frequency causes a large increase in the contrast threshold for a 1 c/deg test grating, but fails to raise the threshold for a squarewave grating of 0.33 c/deg, although the sensitivity of the “channel” tuned to both the third and fifth harmonic components of the squarewave test grating should be thoroughly suppressed. Following sequential adaptation to sinewave gratings of 1 and 3 c/deg spatial frequency, detection of squarewave gratings at 0.33 c/deg likewise remains unaffected. In contrast, after adaptation to a 0.33 c/deg squarewave grating with missing fundamental the contrast threshold for a squarewave test grating of the same frequency is increased by 0.25 log unit, although the higher harmonic component frequencies are less affected than by sequential sinewave adaptation. The results suggest that independent spatial frequency channels detecting harmonic components are not alone sufficient to account for the visibility of low frequency squarewaves

Capacity limitations of visual memory in two-interval comparison of Gabor arrays

The capacity of short-term visual memory (VSTM) was assessed in a two-interval spatial frequency (SF) discrimination task. The cued Gabor target in a multi-element array either increased or decreased in SF across a 2s interstimulus interval (ISI). Distracters as well as target were made to change across ISI so that memory of the individual SF of Gabor elements was required to solve the discrimination. The dynamics of the information loss from visual memory were analysed by manipulating the timing of spatial cues and masks. Cueing the target position before the first display gave thresholds comparable with those for a single Gabor patch. Cues placed after the first display gave higher thresholds indicating some loss of information. Within the ISI there was little increase in threshold or set size effect with cue delay. However there was a sharp rise in thresholds for cue positions after the second display. Gabor masks placed before a mid-ISI cue were more effective than noise masks or Gabor masks placed after the cue. With a cue placed late in the ISI, preceded by a Gabor mask, the masking effect decreased with increasing delay of the mask after the first display. This suggests a selective, dynamic but increasingly durable representation of the initial stimulus is built up in memory, and there is a graded form of “overwriting” of this representation by new stimuli

Economies of scope in Norwegian hospital production - A DEA analysis

From 2002 the Norwegian hospital sector is to be transferred from county to state ownership, organised through regional semiautonomous companies. A major motivation for the reform is to allow for more specialised hospital production. If there are economies or diseconomies of scope, the production of hospital services in a region could become more efficient by exploiting any cost savings that may stem from an optimal division of service production between units. While the theory of economics of scope is well developed, applications have chiefly been concerned with testing for natural monopoly, and few studies of hospital production have been concerned with scope. This paper estimates a multiple output cost function from data on Norwegian hospitals using the non-parametric Data Envelopment Analysis (DEA) method. The cost function is specified with total running costs as the only input, but with seven different outputs to focus on the properties of the output transformation frontier. To overcome the methodological assumption of convexity inherent in DEA, the sample is split into relative specialised and differentiated hospitals, before comparing costs. This partitioning is achieved through grouping as specialised the first and fifth quintiles of the hospitals ranked by the share of the relevant output, since in fact no hospital is fully specialised by producing only one output, or nothing of an output. Exploring scope economies of the best practice cost frontier along three different dimensions, strong economies are found for surgical and medical services, intermediate for inpatient and outpatient production, while elective and emergency care cases have only week economies of scope, which may not be statistically significant. Results for the output mix of individual observations, reveal both economies and diseconomies in the last of these three dimensions. Contrary to these results, average efficiencies are found to be lower for differentiated than specialised hospitals, in all of the dimensions mentioned, although the differences are not very large. Since the DEA method measures hospitals with the largest production of each output as efficient by default, the results for average efficiency may be due to the methods employed.Hospital performance; DEA; Economies of Scope

Testing DEA Models of Efficiency in Norwegian Psychiatric Outpatient Clinics

While measures of output in mental health care are even harder to find than in other health care activities, some indicators are available. In modelling productive efficiency the problem is to select the output variables that best reflect the use of resources, in the sense that these variables have a significant impact on measures of efficiency. The paper analyses cross-sectional data on the psychiatric outpatient clinics of Norway using the Data Envelopment Analysis (DEA) non-parametric efficiency measurement method, and tests the variable specification using statistical tools recently introduced in the literature. In addition to outputs, the importance of different profession or educational groups on efficiency is examined, and results are compared for separate samples of clinics for children and youths (BUP) with clinics for adults (VP).Mental health care; efficiency; psychiatric outpatient clinics; DEA; Norway

Effect of organic pig production systems on performance and meat quality

The present study was carried out to establish knowledge of consequence for setting up guidelines of importance for production of competitive organic pork of high quality. Performance and meat quality characteristics were compared between three organic pig production systems based on indoor housing with access to an outdoor area and a Danish conventional indoor system including 100% concentrate during the finishing feeding stage. The three organic systems used the following three feeding regimes: 100% organic concentrate according to Danish recommendations, 70% organic concentrate (restricted) plus ad libitum organic barley/pea silage and 70% organic concentrate (restricted) plus ad libitum organic clover grass silage, respectively. With exception of a slightly lower daily gain in organic pigs fed 100% concentrate, no significant difference was found in performance and meat quality characteristics compared with results obtained in the conventional system. In contrast and independent of roughage used, organic pigs raised on 70% concentrate had a significant reduction in daily gain (P < 0.001) compared with pigs raised on 100% concentrate, despite the fact that no difference in feed conversion rate was seen between the tested production systems. However, the percentage of leanness increased significantly in meat from organic pigs raised on 70% concentrate plus roughage compared with meat from pigs given 100% concentrate. This was reflected in higher yield (weight) of lean cuts and lower yield of cuts with high fat content from pigs fed 70% concentrate plus roughage. In general, organic feeding resulted in a significantly higher content of polyunsaturated fatty acids in the back fat (1.8%), which increased further when restricted feeding plus roughage (4%) was used. Restricted concentrate feeding gave rise to a decrease in tenderness compared with pork from pigs fed 100% concentrate

Stimulus-specific mechanisms of visual short-term memory

The retention of spatial information in visual short-term memory was assessed by measuring spatial frequency discrimination thresholds with a two-interval forced-choice task varying the time interval between the two gratings to be compared. The memory of spatial frequency information was perfect across 10-sec interstimulus intervals. Presentation of a “memory masker” grating during the interstimulus interval may interfere with short-term memory. This interference depends on the relative spatial frequency of the test and masker gratings, with maximum interference at spatial frequency differences of 1–1.5 octaves and beyond. This range of interference with short-term memory is comparable to the bandwidth of sensory masking or adaptation. A change of the relative orientation of test and masker gratings does not produce interference with spatial frequency discrimination thresholds. These results suggest stimulus-specific interactions at higher-level representations of visual form