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The aim of this study was to investigate the effect of pre-slaughter fasting time, sex and feeding regime on the development of energy metabolism and pH in M. longissimusdorsi (LD) post-mortem in pigs. Two hundred and seventy pigs of the commercial Norwegian crossbreed Noroc (LYLD) were used involving two sexes (gilts and castrates), two feeding regimes (restricted and ad libitum) and four different fasting treatments: (F4) 4h fasting, (F175) 17.5h fasting on the farm, (FO175) 17.5h fasting overnight at the abattoir, and (FO265) 26.5h fasting overnight at the abattoir. Additionally the pigs experienced two different abattoir lairage times as fasting treatment F4 and F175 had a lairage time of 1.5h, while fasting treatment FO175 and FO265 had a lairage time of 23.0 h. A short fasting time of 4 h led to a delayed degradation of glycogen, slow decline in pH and a lower ultimate pH(45 h) post-mortem (pHu) in the LD compared with a fasting time of 26.5 h which resulted in a rapid breakdown of glycogen and pH decline early post-mortem and a high pHu. Proglycogen was degraded in favour of macroglycogen under anaerobic conditions post-mortem. Feeding the animals in the morning before delivery if slaughtered the same day, results in low pH reduction rate and a low pHu compared with pigs fasted overnight either on farm or at the abattoir. Aiming a higher pHu in LD it should be recommended not to feed the pigs in the morning at the day of slaughter.

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The aim of this study was to investigate the effect of pre-slaughter fasting time, sex and feeding regime on water-holding capacity (WHC), colour and sensory properties and their relationship with pH in M. longissimusdorsi (LD) in pigs. 270 pigs of the commercial Norwegian crossbreed Noroc (Norwegian Landrace×Yorkshire sow and Norwegian Landrace×Duroc boar) were used involving two sexes (gilts and castrates), two feeding regimes (restricted and ad libitum) and four fasting treatments: (F4) 4h fasting (control), (F175) 17.5h fasting on the farm, (FO175) 17.5h fasting overnight at the abattoir, and (FO265) 26.5h fasting overnight at the abattoir. Additionally, the pigs experienced two abattoir lairage times as fasting treatments F4 and F175had a lairage time of 1.5 h, while fasting treatments FO175 and FO265 had a lairage time of 23.0h. A short fasting time of 4h led to a delayed decline in pH post-mortem and a lower ultimate pH (pHu) in the LD compared with a fasting time of 26.5h which resulted in a rapid pH decline early post-mortem and a high pHu. Prolonged fasting reduced drip loss, resulted in a darker colour and tended to improve tenderness of the LD. Castrates showed lower drip loss, higher lightness and improved tenderness and juiciness compared with gilts, while ad libitum feeding improved tenderness compared to restricted feeding. There are obvious negative relationships between pHu and drip loss, lightness and tenderness of LD.

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OBJECTIVE: To analyse the topographical distribution of choroidal naevi and to visualise their location in the ocular fundus. METHODS: Data on the size and location of 210 choroidal naevi were converted into a database of two-dimensional retinal charts by means of computer-drawing software. The geometric centre of each lesion was entered into corresponding sectors of the retinal chart. The location of the naevi was computationally visualised by merging the fundus drawings and displaying the number of overlapping lesions on colour-coded contour maps. RESULTS: Five naevi were located exactly between two fundus sectors, and were therefore excluded from the distribution analysis. Ten naevi (5%) were located anterior and 195 (95%) posterior to the equator. A total of 104 naevi (51%) were located in the temporal and 101 (49%) in the nasal hemisphere, and the distribution between the superior and inferior hemisphere was 104 (51%) and 101 (49%), respectively. The distribution did not differ significantly between genders, age groups, or between right and left eyes. More naevi with a diameter of >3 mm were located in the temporal hemisphere (P=0.0004) and anterior to the equator (P=0.006) compared with those with a diameter of

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AIMS: To analyse the distribution of posterior uveal melanoma origin sites and to visualise the patterns of tumour extent in the ocular fundus. METHODS: Data on the size and location of 110 posterior uveal melanomas were converted into a database of two-dimensional retinal charts by means of computer-drawing software. The initiation sites (geometric tumour centres) were entered into corresponding sectors of the retinal chart. The extent of the tumours was visualised by merging the charts and displaying the number of overlapping tumours on colour-coded contour maps. RESULTS: Seventy-one initiation sites (65%) were located in the temporal and 39 (35%) in the nasal hemisphere (p = 0.002). Seventy-six initiation sites (69%) were located posterior and 34 (31%) anterior to the equator. More initiation sites anterior to the equator were observed in large versus small/medium tumours (p = 0.0003), in tumours with a largest basal diameter/height ratio <2 versus > or =2 (p = 0.002), in tumours with a ruptured versus intact Bruch membrane (p = 0.03), in tumours with a mixed/epithelioid versus spindle cell type (p = 0.02) and in tumours leading to metastatic disease (p = 0.003). CONCLUSION: The temporal hemisphere posterior to the equator is the preferential area of melanoma occurrence and growth. For larger and more aggressive tumours, there is a shift towards more peripherally located initiation sites.

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PURPOSE: Accurate monitoring of RF (radio frequency) power and phase is a key part of quality assurance (QA) for phased-array hyperthermia systems. In order to assess the steering capability of the BSD 2000 3D facility, an independent measurement system has been implemented, using a vector voltmeter (VVM) as the measuring device. METHODS: This paper describes the calibration of the RF signal paths from each of the 12 BSD Dodek amplifier outputs to the VVM instrument readout. Periodical network analyser measurements show that the uncertainty of the measured power using the VVM system is <4% for all channels, while the uncertainty of the phase measurements is <0.3 degrees. The values are comparable to those reported for similar monitoring systems and are considered adequate for monitoring of the BSD Dodek steering parameters. RESULTS: Using the VVM system to investigate the accuracy of the BSD Dodek amplifier power and phase control, systematic differences were observed between the requested and the measured power for all channels: At a requested power level of 25 W per channel, the measured power level was on average 15% lower than nominal, whereas at 100 W it was nearly 20% higher. It was also observed that the absolute phase values are nearly 30 degree higher at 25W per channel than at power levels > or = 50W per channel. Under certain circumstances, these issues may reduce target steering accuracy for the BSD 2000 3D system; on the other hand, the Dodek power and phase control stability is found to be acceptable. CONCLUSIONS: The results emphasize the need for accurate, independent online power and phase QA during regional hyperthermia treatments using phased array systems.

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Since December 2001, the Department of Oncology and Medical Physics, Haukeland University Hospital, Norway has been conducting whole body hyperthermia (WBH) studies, treating patients with either ovarian carcinoma or non-Hodgkin lymphomas. Accurate and reliable thermometry instrumentation is important in all types of hyperthermia procedures, particularly in WBH, where the target patient body temperature is 41.8 degrees C. Reliable documentation of side-effects in clinical studies is also dependent on precise temperature monitoring, since in this temperature range even small, but systematic, inaccuracies (0.1-0.2 degrees C) in the temperature monitoring is expected to affect the amount of side effects. Readily available heating and temperature data from previous treatment sessions of the same patient is also valuable for precise temperature control in future treatment sessions. The WBH thermometry system implemented at Haukeland University Hospital is described. It is based on commercially available components, including standard medical thermistor probes, and includes a temperature calibration and verification facility. The thermometry system is accurate, reliable, easy to use, comfortable for the patient and relatively inexpensive. By implementing the Steinhart-Hart polynomial fit to standard medical thermistor probe data, it is shown that the WBH treatment thermometers used can measure the patient body temperatures with a short- and long-term accuracy of +/- 0.01 degrees C.

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Sides of 31 non-stimulated carcasses of young bulls were subjected to the muscle stretching methods Tenderstretch (TS) by pelvic bone suspension or Tendercut (TC) with two skeletal cuts or served as controls by traditional Achilles tendon suspension. The sides were chilled at fast and medium rates, resulting in temperatures of 4-5 and 9°C in the m. longissimus dorsi (LD) at 10 h post mortem. The LDs were examined for sarcomere length, Warner-Bratzler peak shear force and sensory properties after 8 days of ageing at 4°C. At the fast chilling rate, TS and TC increased sarcomere lengths, reduced shear force and improved sensory tenderness of the LDs compared to the controls (P<0.05). At the medium chilling rate, sarcomere lengths increased (P<0.05), but no significant differences were found in shear force or sensory tenderness (P>0.05) of the muscles due to stretching. However, the medium chilling rate was efficient in producing tender LDs without applying muscle stretching methods. TS and TC are feasible alternatives for improving overall tenderness and reducing variation in tenderness of beef LD at cold shortening chilling conditions.

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The single and combined effects of low voltage electrical stimulation (LVES), chilling rate after slaughter, and freezing/thawing during ageing on the tenderness of bovine M. longissimus dorsi were studied. Of 27 young bulls, 14 were exposed to LVES (90 V, 32 s, 15 Hz) immediately after stunning. Four different treatments regarding chilling rate and freezing/thawing were randomly assigned to each of the 27 young bulls. Samples were aged for 7 days at 4°C and analyzed after freezing and thawing. The experimental design allowed direct comparison of different treatment effects and an assessment whether these were additive or not. As expected chilling rate after slaughter had highly significant effects on final tenderness, based on results from a trained sensory panel and Warner Bratzler (WB) shear press analysis. The effect of LVES on final tenderness was not statistically significant. The introduction of a freezing/thawing step during ageing did not significantly affect tenderness. The effects of individual treatments depended on the tenderness level and were relatively larger at high WB shear press values (7-8 kg/cm(2)) than at low values (4-5 kg/cm(2)). The results indicate that the treatment effects were not additive, but that the treatments are alternatives to tenderize beef.

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