Optimal solution of the fractional order breast cancer competition model.

In this article, a fractional order breast cancer competition model (F-BCCM) under the Caputo fractional derivative is analyzed. A new set of basis functions, namely the generalized shifted Legendre polynomials, is proposed to deal with the solutions of F-BCCM. The F-BCCM describes the dynamics involving a variety of cancer factors, such as the stem, tumor and healthy cells, as well as the effects of excess estrogen and the body's natural immune response on the cell populations. After combining the operational matrices with the Lagrange multipliers technique we obtain an optimization method for solving the F-BCCM whose convergence is investigated. Several examples show that a few number of basis functions lead to the satisfactory results. In fact, numerical experiments not only confirm the accuracy but also the practicability and computational efficiency of the devised technique.

Variation of crack intensity factor in three compacted clay liners exposed to annual cycle of atmospheric conditions with and without geotextile cover.

Performance of compacted clay liners commonly used as landfill barrier systems can be subject to decline in terms of hydraulic conductivity if left exposed to atmospheric conditions for an extended period of time prior to placement of overlaying layers. The resulting desiccation cracking can lead to increased hydraulic conductivity. Desiccation crack intensity was studied for three clayey soils commonly used for construction of landfill barrier system in a relatively large scale test setup exposed to real time atmospheric conditions over a complete annual cycle. A white separator geotextile cover was presumed to be capable of reducing the intensity of desiccation cracking through absorbing and maintaining higher amounts of moisture and reducing the temperature of the soil surface in comparison to a directly exposed soil surface. Desiccation cracking was monitored using a digital imaging technique for three compacted clay liners in two sets, one open to air and the second covered with the white geotextile. Crack intensity factor approached a relatively stable phase after certain cycles corresponding to atmospheric dry wet cycles. The results indicated that the white separator geotextile was capable of reducing the crack intensity factor by 37.4-45.9% throughout the experiment including the cyclic phase of desiccation cracking. During the stable phase, the maximum reduction in crack intensity factor of 90.4% as a result of applying geotextile cover was observed for the soil with the lowest plastic index and clay content and therefore the lowest magnitude of crack intensity factor. The other two soils with similar clay content but different plastic index showed 23.6% and 52.2% reductions in crack intensity factor after cyclic phase when covered with geotextile.

Lamb survival in Australian Merino sheep: a genetic analysis.

Direct and maternal components of variance for lamb survival to birth, 7 d, and weaning (110 d) were estimated by REML procedures in a flock of Australian Merino sheep. A total of 14,142 lambs, the progeny of 421 sires and 3,666 dams, born between 1975 and 1983 were available for analysis. The study has produced some of the most precise estimates of genetic parameters for lamb survival in the Australian Merino. Very low heritabilities for lamb viability (0.03) and the performance of the dam or ewe rearing ability (0.07) suggest that genetic solutions to lamb survival are unlikely to be significant. But, despite the low heritabilities, there is still potential for improvement through selective breeding. The estimated repeatability of at least 0.10 shows that multiple records on the rearing ability of a ewe over its lifetime can increase selection accuracy. More importantly, such repeatabilities indicate that current generation improvement can be achieved by culling ewes from the breeding flock with poor rearing ability. Despite maternal bond score and lamb birth weight being highly repeatable and moderately heritable traits, correlations with lamb survival were essentially zero. These traits therefore have no value as indirect selection criteria for Merino lamb survival.

Phenotypic aspects of lamb survival in Australian Merino sheep.

Lamb survival in Australian Merino sheep was investigated using survival records from 14,142 lambs born between 1975 and 1983. This data set included roll calls of live lambs at birth, 7 d, marking (30 d), and weaning (110 d), which allowed 4 binomial traits (alive or dead) to be recorded for each lamb at each time interval. The average survival to weaning was 72.4% with 23% of singles, 32% of twins, and 45% of multiple-born lambs not surviving to weaning. The timing of lamb loss was consistent across birth types; 6% died within 24 h of birth, a further 14% by 7 d, 3% between 7 and 30 d, and 8% between 30 and 110 d. Partitioning of phenotypic variation revealed that after the first postpartum week, mothering ability of Australian Merino ewes is not an important factor in lamb survival. Some ewes repeatedly lose lambs at birth and in the early postnatal period, but the intraclass correlation decreased by a factor of 10 for survival after 7 d of age (0.096 at birth and 0.100 at 7 d, falling to 0.009 at marking and 0.018 at weaning). This study examined the relationships of lamb survival with lamb birth weight and found varying relationships at each time period. Whereas birth weight had a highly significant curvilinear relationship with survival to weaning, the relationship was flatter for survival to 24 h with only small differences between average birth weights and the birth weight at which survival was optimized (-0.04, 0.28, and 0.54 kg for single-, twin-, and multiple-born lambs, respectively). This suggests that any management interventions to increase birth weight may increase the risk of death to both lamb and ewe during the lambing process due to dystocia. Among twin-born lambs there was a carryover effect of losses at birth on subsequent loss in the first week of life. Survival to 7 d of age was highly dependent on the survival of the littermate, favoring those whose littermate survived, but after the first week, this trend was reversed. Lamb birthcoat score had a small positive impact on survival only at birth.

Genetic parameters for carcass and meat quality traits and their relationships to liveweight and wool production in hogget Merino rams.

Genetic parameters for carcass and meat quality traits of about 18-month-old Merino rams (n = 5870), the progeny of 543 sires from three research resource flocks, were estimated. The estimates of heritability for hot carcass weight (HCW) and the various fat and muscle dimension measurements were moderate and ranged from 0.20 to 0.37. The brightness of meat (colour L*, 0.18 +/- 0.03 standard error) and meat pH (0.22 +/- 0.03) also had moderate estimates of heritability, although meat relative redness (colour a*, 0.10 +/- 0.03) and relative yellowness (colour b*, 0.10 +/- 0.03) were lower. Heritability estimates for live weights were moderate and ranged from 0.29 to 0.41 with significant permanent maternal environmental effects (0.13 to 0.10). The heritability estimates for the hogget wool traits were moderate to high and ranged from 0.27 to 0.60. The ultrasound measurements of fat depth (FATUS) and eye muscle depth (EMDUS) on live animals were highly genetically correlated with the corresponding carcass measurements (0.69 +/- 0.09 FATC and 0.77 +/- 0.07 EMD). Carcass tissue depth (FATGR) had moderate to low genetic correlations with carcass muscle measurements [0.18 +/- 0.10 EMD and 0.05 +/- 0.10 eye muscle area (EMA)], while those with FATC were negative. The genetic correlation between EMD and eye muscle width (EMW) was 0.41 +/- 0.08, while EMA was highly correlated with EMD (0.89 +/- 0.0) and EMW (0.78 +/- 0.04). The genetic correlations for muscle colour with muscle measurements were moderately negative, while those with fat measurements were close to zero. Meat pH was positively correlated with muscle measurements (0.14 to 0.17) and negatively correlated with fat measurements (-0.06 to -0.18). EMDUS also showed a similar pattern of correlations to EMD with meat quality indicator traits, although FATUS had positive correlations with these traits which were generally smaller than their standard error. The genetic correlations among the meat colour traits were high and positive while those with meat pH were high and negative, which were all in the favourable direction. Generally, phenotypic correlations were similar or slightly lower than the corresponding genetic correlations. There were generally small to moderate negative genetic correlations between clean fleece weight (CFW) and carcass fat traits while those with muscle traits were close to zero. As the Merino is already a relatively lean breed, this implies that particular attention should be given to this relationship in Merino breeding programmes to prevent the reduction of fat reserves as a correlated response to selection for increased fleece weight. The ultrasound scan traits generally showed a similar pattern to the corresponding carcass fat and muscle traits. There was a small unfavourable genetic correlation between CFW and meat pH (0.19 +/- 0.07).

Genetic correlations between ewe reproduction and carcass and meat quality traits in Merino sheep.

Genetic correlations between reproduction traits in ewes and carcass and meat quality traits in Merino rams were obtained using restricted maximum likelihood procedures. The carcass data were from 5870 Merino rams slaughtered at approximately 18 months of age that were the progeny of 543 sires from three research resource flocks over 7 years. The carcass traits included ultrasound scan fat and eye muscle depth (EMDUS) measured on live animals, dressing percentage and carcass tissue depth (at the GR site FATGR and C site FATC), eye muscle depth, width and area and the meat quality indicator traits of muscle final pH and colour (L*, a*, b*). The reproduction data consisted of 13 464 ewe joining records for number of lambs born and weaned and 9015 records for LS. The genetic correlations between reproduction and fat measurements were negative (range -0.06 +/- 0.12 to -0.37 +/- 0.12), with smaller correlations for live measurement than carcass traits. There were small favourable genetic correlations between reproduction traits and muscle depth in live rams (EMDUS, 0.10 +/- 0.12 to 0.20 +/- 0.12), although those with carcass muscle traits were close to zero. The reproduction traits were independent of meat colour L* (relative brightness), but tended to be favourably correlated with meat colour a* (relative redness, 0.12 +/- 0.17 to 0.19 +/- 0.16). There was a tendency for meat final pH to have small negative favourable genetic correlations with reproduction traits (0.05 +/- 0.11 to -0.17 +/- 0.12). This study indicates that there is no antagonism between reproduction traits and carcass and meat quality indicator traits, with scope for joint improvement of reproduction, carcass and meat quality traits in Merino sheep.

Genetic correlations among and between wool, growth and reproduction traits in Merino sheep.

Data from seven research resource flocks across Australia were combined to provide accurate estimates of genetic correlations among production traits in Merino sheep. The flocks represented contemporary Australian Merino fine, medium and broad wool strains over the past 30 years. Over 110,000 records were available for analysis for each of the major wool traits, and 50,000 records for reproduction and growth traits with over 2700 sires and 25,000 dams. Individual models developed from the single trait analyses were extended to the various combinations of two-trait models to obtain genetic correlations among six wool traits [clean fleece weight (CFW), greasy fleece weight, fibre diameter (FD), yield, coefficient of variation of fibre diameter and standard deviation of fibre diameter], four growth traits [birth weight, weaning weight, yearling weight (YWT), and hogget weight] and four reproduction traits [fertility, litter size, lambs born per ewe joined, lambs weaned per ewe joined (LW/EJ)]. This study has provided for the first time a comprehensive matrix of genetic correlations among these 14 wool, growth and reproduction traits. The large size of the data set has also provided estimates with very low standard errors. A moderate positive genetic correlation was observed between CFW and FD (0.29 +/- 0.02). YWT was positively correlated with CFW (0.23 +/- 0.04), FD (0.17 +/- 0.04) and LWEJ (0.58 +/- 0.06), while LW/EJ was negatively correlated with CFW (-0.26 +/- 0.05) and positively correlated with FD (0.06 +/- 0.04) and LS (0.68 +/- 0.04). These genetic correlations, together with the estimates of heritability and other parameters provide the basis for more accurate prediction of outcomes in complex sheep-breeding programmes designed to improve several traits.

Impact of Cre1, Cre8 and Cre3 genes on cereal cyst nematode resistance in wheat.

The cereal cyst nematode (CCN; Heterodera avenae), a root disease of cereal crops, is a major economic constraint in many wheat (Triticum aestivum)-growing areas of the world. The objective of this study was to assess the impact of the Cre1, Cre8 and Cre3 genes on CCN resistance. A population of 92 doubled-haploid (DH) lines derived from a cross between wheat cvs. Frame and Silverstar as well as 1,851 wheat breeding lines were screened for CCN resistance at the Primary Industries Research Victoria (PIRVic). A second population of 9,470 wheat breeding lines was screened at the South Australian Research and Development Institute (SARDI). Cre3 had the largest impact on reducing the number of female cysts, followed by Cre1 and Cre8. There was no significant difference in number of cysts between DH lines with or without the Cre8 marker, suggesting that the marker is not perfectly linked to Cre8. The estimated heritabilities were 0.32 in the DH population, 0.48 in the PIRVic data set and 0.32 in the SARDI data set, which confirm that this is a trait of low heritability. The repeatability of CCN resistance improved with an increase in the number of plants assessed per line-up to ten. However, 85-88% of the improvement was achieved with the assessments of the first five plants.

Video image analysis in the Australian meat industry - precision and accuracy of predicting lean meat yield in lamb carcasses.

A wide selection of lamb types of mixed sex (ewes and wethers) were slaughtered at a commercial abattoir and during this process images of 360 carcasses were obtained online using the VIAScan® system developed by Meat and Livestock Australia. Soft tissue depth at the GR site (thickness of tissue over the 12th rib 110 mm from the midline) was measured by an abattoir employee using the AUS-MEAT sheep probe (PGR). Another measure of this thickness was taken in the chiller using a GR knife (NGR). Each carcass was subsequently broken down to a range of trimmed boneless retail cuts and the lean meat yield determined. The current industry model for predicting meat yield uses hot carcass weight (HCW) and tissue depth at the GR site. A low level of accuracy and precision was found when HCW and PGR were used to predict lean meat yield (R(2)=0.19, r.s.d.=2.80%), which could be improved markedly when PGR was replaced by NGR (R(2)=0.41, r.s.d.=2.39%). If the GR measures were replaced by 8 VIAScan® measures then greater prediction accuracy could be achieved (R(2)=0.52, r.s.d.=2.17%). A similar result was achieved when the model was based on principal components (PCs) computed from the 8 VIAScan® measures (R(2)=0.52, r.s.d.=2.17%). The use of PCs also improved the stability of the model compared to a regression model based on HCW and NGR. The transportability of the models was tested by randomly dividing the data set and comparing coefficients and the level of accuracy and precision. Those models based on PCs were superior to those based on regression. It is demonstrated that with the appropriate modeling the VIAScan® system offers a workable method for predicting lean meat yield automatically.

A national audit of retail lamb loin quality in Australia.

A retail audit of lamb loin tenderness was conducted over a 12-month period to determine the variation in tenderness of Australian lamb. Tenderness was objectively measured using Warner-Bratzler (WB) shear force. Muscle pH and cooking loss were determined on all samples and colour was measured on a sub-sample of loins. A total of 909 midloins from retail butcher shops and supermarkets located in four Australian capital cities (Sydney, Canberra, Melbourne, and Perth) were evaluated at four sampling times (December 1997 and March, June, and October 1998). Overall, 20.3% of all midloins purchased had a WB shear force value above the threshold level of 5 kg. Generic samples from Melbourne butcher shops were similar for WB shear force on average to the generic samples from Canberra and Sydney, whereas those from Melbourne supermarkets had significantly (P<0.001) higher WB shear force and were in line with generic samples from Perth. In both Canberra and Perth, alliance (branded) lamb had a greater WB shear force (P<0.05) than generic lamb. No relationship was found between price per kg and shear force (r=0.02) for loins purchased in Sydney (n=220). Price per kg differed between months (P<0.001) and suburbs (P<0.001), but not between retail butcher shops and supermarkets. Of the midloins tested, 10.3% had a pH above the critical point of 5.8. Midloins from the December 1997 sampling had a lower pH (P<0.01) than those sampled at other months. Those sampled in Melbourne and Perth had a similar mean pH, which were lower (P<0.001) than Canberra and Sydney samples. The findings from this quality audit suggest that there is room to improve the tenderness of Australian lamb sold in the domestic market. A lamb eating quality assurance system, based on set protocols, is one approach that is currently being investigated in Australia to ensure the supply of consistently high eating quality lamb to consumers.

Diverse lamb genotypes. 3. Eating quality and the relationship between its objective measurement and sensory assessment.

The effect of genotype on eating quality was evaluated on m. Longissimus thoracis et lumborum (LTL) muscle of 60 lambs. The lambs were sired by a selection of Texel (T), Poll Dorset (PD), Border Leicester (BL) and Merino (M) rams, crossed with Border Leicester x Merino (BLM) and Merino (M) ewes giving six genotypes (TxBLM, PDxBLM, TxM, PDxM, BLxM and MxM). The relationships between sensory panel assessment of eating quality attributes and pH, cooking loss and shear force were also investigated. No significant differences were observed between genotypes for panel assessment of tenderness, juiciness, aroma liking, aroma strength, flavour liking, overall acceptability and rating. MxM lambs had a significantly (P<0.05) higher flavour strength than BLxM lambs. pH was a poor indicator of any eating quality attributes, except aroma strength (r=0.3, P<0.05). Warner Bratzler shear force value (WB) and tenderness showed a significant (P<0.001) negative correlation (-0.7). Tenderness, flavour and juiciness were the most important sensory attributes, explaining 86.5% of the total variation in overall acceptability.

Diverse lamb genotypes 4. Predicting the yield of saleable meat and high value trimmed cuts from carcass measurements.

To determine how current predictors of carcass and cut yield perform in the Australian lamb industry a large study was undertaken using diverse genotypes. Carcass measurements and yield data were obtained for 591 lambs representing two sexes (cryptorchids, ewes). The lambs were sired by a selection of Texel (T), Poll Dorset (PD), Border Leicester (BL) and Merino (M) rams crossed with Border Leicester×Merino (BLM) and Merino (M) ewes giving six genotypes (T×BLM, PD×BLM, T×M, PD×M, BL×M, M×M). The percentage yield of saleable meat, hindquarter, loin and a range of trimmed cuts were predicted using models based on hot carcass weight, EUROP conformation score, m. longissimus thoracis et lumborum area (LL area) in combination with three different measures of carcass fatness: (1) the depth of muscle and fat tissue from the surface of the carcass to the lateral surface of 12th rib, 110 mm from the midline (GR); (2) fat depth over the LL at the deepest part of the muscle (FATC); and (3) fat depth at the 5th rib, 110 mm from the midline (FAT5). FAT5 was identified as the most accurate and robust (stable) fat measurement for the prediction of saleable meat yield in a production system based on diverse genotypes. Using GR as a fatness measurement led to overestimation of fatness level and underestimation of yield in T sired lambs. Conformation score after carcass weight and any of the fat measurements improved (P<0.01) the prediction of the yield of saleable meat, hindquarter, loin and all trimmed lamb cuts with the exception of the ribloin (rack). LL area added significantly (P<0.01) to the prediction of the yield of saleable meat, hindquarter and trimmed lamb cuts, but not for the midloin and neck fillet at a constant carcass weight and fatness. Large proportions of the variation in all yields were unaccounted for, even after the inclusion of either conformation or LL area. Predictions based on carcass weight and any of the three different fat measurements were not very accurate. Although the addition of LL area as a predictor significantly (P<0.01) increased the accuracy of the predictions the results suggest that the current description system for lamb carcases in Australia needs to be re-examined.

Abdominal tuberculosis: a presumptive diagnosis.

BACKGROUND: Abdominal tuberculosis (TB) is common. But the diagnosis of abdominal TB is fraught with difficulties as it is often not possible to get a microbiological confirmation of the infection. We therefore undertook this study to highlight those pertinent clinical and laboratory features which would enable one to make a provisional diagnosis of abdominal TB early, to pave way for a trial of anti-tuberculosis chemotherapy. METHOD: This is a retrospective study of 12 patients treated for abdominal TB in our department over a period of 2 years. FINDINGS: Seven of the patients suffered from chronic diarrhoea for periods ranging from 4 weeks to 12 months. Four patients had progressive abdominal distension (ascites). The last patient came in with multiple abdominal swellings. Seven patients had clinical and biochemical features of malabsorption. Another 9 patients also had persistent pyrexia. The ascitic fluid was exudative in the 4 patients mentioned earlier. A definitive diagnosis could not be established in any of these patients. The diagnosis of abdominal TB was thus one of exclusion in these patients who showed prompt response to anti-tuberculosis therapy. CONCLUSION: Our study justifies a trial of anti-TB chemotherapy in TB endemic areas in the following clinical situations: (a) patients with chronic diarrhoea of unknown aetiology and (b) patients with exudative ascitic fluid, after all other possible causes, have been excluded. A prompt response to anti-TB therapy should be accepted as sufficient ground for the diagnosis of abdominal TB even when histopathological or microbiological confirmation of the disease is not possible. Our study reflects the experience of other workers from Third World countries.

Effect of castration and cryptorchidism on fatty acid content of ovine adipose tissue.

Fatty acid analyses of perinephric and subcutaneous adipose tissue were made on 50 of Mehraban and Bakhriari breeds lambs to determine the effect of castration and cryptorchidism on ovine lipid composition. The level of stearic acid was significantly higher (p < 0·05) in cryptorchids than in wethers. Rams were also higher (p < 0·05) in the percentage of linoleic acid of the internal adipose tissue than wethers. The percentage of palmitic acid of subcutaneous tissue was higher (p < 0·05) in cryptorchid than rams. There was a tendency toward less saturated (palmitic and stearic) acids, but more unsaturated (oleic and linoleic) acids in rams than in wethers. The perinephric fat was more saturated than subcutaneous fat.