bluuebunny/crossref_metadata_2025 huggingface dataset:
Attainment of puberty and reproductive performance in Clun Forest ewe lambs
Authors: Dýrmundsson Ó. R. , Lees J. L.
Published: March 2009

Certain aspects of puberal development and reproductive performance in Clun Forest ewe lambs with a wide range of birth dates were investigated during the two seasons 1969–71. Of 33 ewe lambs born in the spring of 1969, 26 exhibited their first oestrus at a mean date of 8 November 1969 ± 2·5 days, the mean age being 228·3 ± 2·4 days and the mean body weight 36·3 ± 0·9 kg. The lambs which failed to breed in their first year, together with lambs born in the autumn of 1969, attained puberty during the autumn of 1970. Twenty-three ewe lambs carried foetuses to term in the spring of 1970 and had a mean lambing rate of 113·0 ± 7%. Of 84 ewe lambs born in the spring of 1970, 73 attained puberty in the first year of life at a mean date of 11 November 1970 ± 2·7 days, the mean age being 223·7 ± 3·0 days and the mean body weight 32·2 ± 0·5 kg. Cyclic activity of ewe lambs born in 1970 was recorded throughout their first breeding season. They experienced their last oestrus of the season at a mean date of 24 January 1971 ± 2·2 days, the mean age being 296·9 ±3·9 days and the mean body weight 32·4 ± 0·6 kg. The mid-breeding season was 18 December 1970, coinciding with the shortest days, and the mean number of heats exhibited throughout the season was 5·15 ± 0·24 per lamb.

Marked individual variation existed in age and body weight at puberty and in breeding activity, largely due to differences in date of birth and growth rate during rearing. Ewe lambs born early tended to experience their first oestrus earlier in the season than late born lambs but they did so at a higher age and heavier body weight. Fast growth rate and earliness of puberty were associated with extended duration and enhanced regularity of cyclic activity. Time of birth was clearly of fundamental importance in relation to the onset and duration of breeding activity in the ewe lambs included in the present study.

Adult rams of three breeds were found to vary consistently in the proportion of ewe lambs which they detected in oestrus, rams of the lambs' own breed being most efficient.
Errors associated with expressing pasture intake as dry rather than organic matter at high stocking intensities
Authors: O'Donovan P. B.
Published: March 2009

Following both a low and high plane of winter feeding two groups of 18 bullocks each were stocked at 2·5 (low), 4·3 (medium) and 6·2 (high) bullocks per hectare. The Hereford × Shorthorn bullocks averaging 350 kg live weight were rotationally grazed on ten plots, seven of which contained a H.I. white clover mixture and the remaining three contained permanent pasture. Pasture digestibility and intake were determined for 16 weekly periods between early April and late September. In vitro digestibility was determined on samples obtained by means of two rumen-fistulated bullocks. A gelatin capsule containing 10 g of chromic oxide was administered daily to each bullock to estimate faecal output. Digestibility, faecal output and intake were expressed on both a dry and organic-matter basis. Increasing the stocking rate resulted in a corresponding decrease in organic matter (OM) percentage of the faeces but the magnitude of the differences varied throughout the growing season. The average decline (all 16 periods) was linear, the OM percentage of faeces being 80·9, 76·8 and 72·6 for low, medium and high stocking rates, respectively. Faecal ash content of rectal samples and those taken from the pasture differed significantly only in a few instances, indicating that pasture faecal contamination may not be serious if careful sampling is practised. Higher ash intakes at high stocking intensities are reflected in herbage intake errors when results are expressed as dry matter instead of organic matter.
An experiment begun in 1958 measuring effects of N, P and K fertilizers on yield and N, P and K contents of grass:2. Residual effects on arable crops, 1968–76
Authors: Penny A. , Widdowson F. V.
Published: March 2009

An experiment at Rothamsted during 1958–67 measured effects on yield, on K uptake and on soil K of applying all combinations of 38, 75 and 113 kg N and 0, 31 and 62 kg K/ha per cut to grass leys, which were cut and removed. Soil K was depleted most where most N and least K were given. Annual applications of 0, 33 and 66 kg P/ha were also tested; soil P was not depleted. The grass was then ploughed.

In 1968, residual effects were measured by spring wheat. In 1969 and in 1970 104 kg/ha of fresh K was applied on half of each plot; potatoes (1969) and spring wheat (1970) valued residual and fresh effects of K.

In 1971 potatoes tested 0, 104 and 208 kg/ha of fresh K, cumulatively with the three amounts given to the grass and also extra K (104 kg/ha) on half-plots, cumulatively with that given in 1969 and 1970. In 1972 winter wheat, and in 1974 and 1975 spring barley, measured residues of all treatments previously applied (the site was fallowed in 1973).

Finally, in 1976, potatoes tested 0, 156 and 312 kg/ha of fresh K on whole plots, cumulatively with the previous dressings of K, and also 156 kg/ha of extra K on half-plots, again cumulatively. All these test crops were given basal N.

Yields and K contents of wheat at ear emergence and yields of wheat grain were largest after grass given 38 kg N and 62 kg K/ha per cut, because here soil K depletion was least. Wheat grain yields benefited consistently from fresh K. K content of the wheat at ear emergence was a good indicator of the need for K, but K content of grain was not, because it was unaltered by K fertilizer. Barley was a poor test crop for K, because yields of grain were little affected by previous treatments.

Percentage K in potato leaves (in July in 1969 and 1971, in August in 1976) and yield of tubers were well correlated. Largest yields in 1969, 1971 and 1976 came where the leaves contained 3·43, 3·76 and 2·82% K, respectively, i.e. from soil containing most exchangeable K, plus most fresh K. There was no indication that maximum yields had been obtained, so the largest amounts (kg/ha) of fresh K tested (104 in 1969, 312 in 1971 and 468 in 1976) were insufficient to counteract depletion of soil K by the grass. Because the grass did not deplete soil P, the test crops benefited only little from either residual or fresh P.
Environmental effects on seed oil percentage and fatty acid composition in white lupin (Lupinus albus)
Authors: Williams Watkin , McGibbon R.
Published: March 2009

The effects of temperature, light intensity and nitrogen supply on the amount and fatty acid composition of the seed oil in Lupinus albus has been investigated. The percentage seed oil was reduced and its degree of saturation increased at higher temperatures. High temperatures during the dark period caused a reduction in percentage oil only when combined with day temperature of 20 °C, indicating a highly specific interaction between day and night temperatures. Shading reduced oil content, an effect which may determine response to population density and the optimal phenotype for high-oil cultivars.
The dam-break problem for viscous fluids in the high-capillary-number limit
Authors: ANCEY C. , COCHARD S. , ANDREINI N.
Published: March 2009

Experiments were undertaken to investigate dam-break flows where a finite volume of highly viscous fluid (glucose with viscosity μ ≈ 350 Pa s) maintained behind a lock gate was released into a horizontal or inclined flume. The resulting sequence of flow-depth profiles was tracked using a three-dimensional visualization system. In the low-Reynolds-number and high-capillary-number limits, analytical solutions can be obtained from the Navier–Stokes equations using lubrication theory and matched asymptotic expansions. At shallow slopes, similarity solutions can also be worked out. While the variation in the front position scaled with time as predicted by theory for both horizontal and sloping flumes, there was a systematic delay in the front position observed. Moreover, taking a closer look at the experimental flow-depth profiles shows that they were similar, but they noticeably deviated from the theoretical similarity form for horizontal planes. For sloping beds, the flow-depth profile is correctly predicted provided that different scalings are used at shallow and large slopes.
Microvolt T-wave alternans and the selective use of implantable cardioverter defibrillators for primary prevention: A cost-effectiveness study
Authors: Filion Kristian B. , Xie Xuanqian , van der Avoort Charlotte J. , Dendukuri Nandini , Brophy James M.
Published: March 2009

Objectives:Implantable cardioverter defibrillators (ICDs) are an effective but expensive treatment for the prevention of sudden cardiac deaths in patients with severe left-ventricular dysfunction. Recent studies suggest that microvolt T-wave alternans (MTWA) predicts mortality and severe arrhythmic events in this population. However, the impact of MTWA on ICD cost-effectiveness is unknown.

Methods:A Markov decision-analysis model evaluated three treatment strategies for primary prevention in patients with severe left-ventricular dysfunction: (i) medical therapy for all; (ii) ICD therapy for all; and (iii) selective ICD therapy based on non-negative (positive or indeterminate) MTWA test results. Incremental cost-effectiveness ratios (ICER) were calculated from the perspective of a third party payer using a 10-year time horizon. Sensitivity analyses examined the robustness of the estimates.

Results:A treatment strategy involving ICD therapy in all patients was associated with an ICER of $121,800/quality-adjusted life-year (QALY) compared with medical therapy, whereas a treatment strategy involving the selective use of ICDs based on MTWA test results was associated with an ICER of $108,900/QALY compared with medical therapy. Sensitivity analyses suggest that, under most scenarios, the selective use of ICDs based on MTWA results does not decrease the ICER to below $100,000/QALY.

Conclusion:MTWA only marginally improves the cost-effectiveness of ICDs for primary prevention in patients with severe left-ventricular dysfunction. There remains a need for improved means to effectively identify which patients will derive the greatest benefit from ICD implantation.
Modeling the cost-effectiveness of treatment of rheumatoid arthritis with rituximab using registry data from Southern Sweden
Authors: Lindgren Peter , Geborek Pierre , Kobelt Gisela
Published: March 2009

Objectives:The aim of this study was to estimate the cost-effectiveness of rituximab in patients not responding adequately to the first tumor necrosis factor (TNF) inhibitor using a model constructed to predict resource consumption and health outcomes in a population-based registry of biological treatments in Southern Sweden (SSATG).

Methods:The model was developed as a discrete event simulation model, using SSATG data for the years 1999–2007. The data set included 1,903 patients with complete data on treatments (up to three treatment lines), functional capacity (HAQ), disease activity (DAS28), and utility (EQ-5D). Resource consumption was based on a regular population-based survey of patients in Southern Sweden. Rituximab was incorporated as second line treatment, using effectiveness data for the active group (N= 311) in a clinical trial comparing rituximab to placebo (REFLEX). It is thus compared to the mix of second line biologics used in SSATG. The analysis starts after failure of the first TNF inhibitor. Results are reported as costs (€2008) per quality-adjusted life-year (QALY; both discounted 3 percent), for the societal perspective in Sweden.

Results:Total costs in the rituximab strategy are estimated at €401,100 compared with €403,000 in the TNF-inhibitor arm. Total QALYs are 5.98 and 5.78, respectively. The findings were found to be robust in extensive sensitivity analysis.

Conclusions:In our model, a strategy where rituximab is used as second line treatment after failure of the first TNF inhibitor provides a small saving (essentially due to the lower price of rituximab) and a QALY gain (due to better effect than the mix of second line TNF inhibitors).
Economic evaluation of drug-eluting stents compared to bare metal stents using a large prospective study in Ontario
Authors: Goeree Ron , Bowen James M. , Blackhouse Gord , Lazzam Charles , Cohen Eric , Chiu Maria , Hopkins Rob , Tarride Jean-Eric , Tu Jack V.
Published: March 2009

Objectives:To determine the cost-effectiveness (CE) and cost-utility (CU) of drug-eluting stents (DES) compared to bare metal stents (BMS) in Ontario using a large prospective “real-world” cohort study and determine the extent to which results vary by patient risk subgroups.

Methods:A field evaluation was conducted based on all stent procedures in the province of Ontario between December 1, 2003, and March 31, 2005, with a minimum subject follow-up of 1 year. Effectiveness data from the study using a propensity-score matched cohort were combined with resource utilization and cost data and quality of life (QOL) data from the published literature in a decision analytic modeling framework to determine 2-year cost-effectiveness (cost per revascularization avoided) and cost-utility (cost per quality-adjusted life-year ([QALY] gained). Stochastic model parameter uncertainty was expressed using probability distributions and analyzed using a probabilistic model. Modeling assumptions were assessed using traditional deterministic sensitivity analysis.

Results:Significant differences in revascularization rates were found for patients with two or more high risk factors. Despite these differences, the CE and CU of DES remained high (e.g., $419,000 per QALY gained in the most favorable patient risk subgroup). In sensitivity analysis, the difference in cost between DES and BMS had an impact on the CE and CU results. For example, at a price differential of $500, the CU of DES was $20,000/QALY for one patient subgroup and DES was dominant (i.e., less costly and more effective) in another.

Conclusions:At current prices, the CE/CU of DES compared with BMS is high even in patient high risk subgroups. As the relative price of DES decrease, the value for money attractiveness of DES increases, especially for selected high risk patients.
Clinical decision rules for the use of liquor diagnostics in hospitalized neurology patients reduced costs without affecting clinical outcomes
Authors: Haschke-Becher Elisabeth , Totzke Uwe , Afazel Shahrzad , Johansson Tim , Schwarz Markus , Ladurner Gunther , Wild Claudia
Published: March 2009

Objectives:Excessive use of laboratory diagnostics has been common. This study aimed to evaluate whether clinical decision rules for the use of liquor diagnostics would enable cost containment without affecting medical care.

Methods:This was a single-center, retrospective, cost-minimization study based on the records of all 16,319 patients hospitalized and discharged at a Neurology Clinic in Austria between 2004 and 2006. Cost of liquor diagnostics, discharge diagnosis, duration of hospital stay, and mortality were compared along the line before, during, and after implementation of decision rules in mid-2005.

Results:There were no significant changes in patient characteristics over time, not in the diagnoses at discharge, nor in the percentage of patients undergoing liquor diagnostics. The average number of tests per patient significantly decreased. Standard tests largely replaced serological tests for infections, regardless of diagnosis. Annual costs for liquor diagnostics decreased by 32.9 percent. Overall, the duration of hospital stay and mortality significantly decreased as well; however, differences were not significant for any single diagnosis-related group.

Conclusions:Diagnostic algorithms may allow cost containment without affecting medical care.
In search of the evidentiary foundation of published Canadian economic evaluations (2001–06)
Authors: Tarride Jean-Eric , Lim Morgan E. , Bowen James M. , McCarron Catherine Elizabeth , Blackhouse Gord , Hopkins Robert , O'Reilly Daria , Xie Feng , Goeree Ron
Published: March 2009

Objectives:The aim of this study was to present a review of economic evaluations conducted from a Canadian perspective and to characterize sources of evidence and statistical methods to analyze effectiveness measures, resource utilization, and uncertainty.

Methods:A search strategy was developed to identify Canadian economic evaluations published between January 2001 and June 2006. A standardized abstraction form was used to extract key data (e.g., study design, data sources, statistical methods).

Results:A total of 153 unique studies were included for review, of which 75 were evaluations of drug therapies and less than half were funded by industry. Cost-effectiveness analysis was the most common type of economic evaluation and 80 percent of the studies used modeling techniques. A single source of evidence for effectiveness measures was used in half of the studies. Statistical methods were commonly reported to compare effectiveness measures when the economic evaluation was conducted alongside a clinical trial but less commonly when determining effectiveness input parameters in model-based economic evaluations, or to analyze resource utilization data. Authors relied mostly on univariate sensitivity analyses to explore uncertainty.

Conclusions:This review identifies the need to improve the conduct and reporting of statistical methods for economic evaluations to improve confidence in the results.
Thin current sheet in the substorm late growth phase: Modeling of THEMIS observations
Authors: Zhou X.‐Z. , Angelopoulos V. , Runov A. , Sitnov M. I. , Coroniti F. , Pritchett P. , Pu Z. Y. , Zong Q.‐G. , McFadden J. P. , Larson D. , Glassmeier K.‐H.
Published: March 2009

The structure of a thin current sheet prior to the expansion onset of a substorm event that occurred on 26 February 2008 is studied in the near‐Earth magnetotail on the basis of Time History of Events and Macroscale Interactions During Substorms (THEMIS) observations. During this time interval, the ion distribution showed mushroom‐shaped structures with clear nongyrotropic features, indicating that the warmer component of the ions was unmagnetized, which becomes possible only if the gyroradii of these ions are comparable with the current sheet thickness. By comparing the observations with the model proposed by Sitnov et al. (2003), which is a modification of the Harris (1962) model by considering the effect of the meandering ions in thin current sheets, we reconstruct the current sheet structure in the late growth phase of the substorm. Warmer ions, mostly following meandering orbits across the neutral sheet, are found to remarkably alter the current sheet profiles and therefore play an important role in the formation of the thin current sheet.
A probabilistic approach to the effect of hydrogen bonding on the hydrophobic attraction
Authors: Djikaev Y. S. , Ruckenstein Eli
Published: March 2009

Water molecules, belonging to the first hydration shell around a hydrophobic particle, form fewer hydrogen bonds than bulk molecules. On the other hand, the former (boundary) bonds may be slightly stronger than the latter. When two hydrophobic particles are sufficiently close to each other, the disruption of water-water hydrogen bonds in their first hydration layers can give rise to an additional contribution to their overall interaction potential. Here we present a probabilistic approach to studying this phenomenon. The proposed method allows one to determine the average number of hydrogen bonds per water molecule in the first hydration shell. Numerical evaluations show that in the interplay between a decrease in the number of boundary bonds per water molecule and the enhancement of such a bond the former effect is clearly predominant. As a result, the disruption of boundary hydrogen bonds, which occurs when the first two hydration shells of two particles overlap, leads to an attractive contribution to the overall particle interaction. This contribution is naturally short range, appearing only when the separation between the two particles becomes smaller than four lengths of a hydrogen bond. It is greater than the overall van der Waals interaction potential of the same hydrophobic particles (with typical Hamaker constants) by at least an order of magnitude.
Neural origin of cognitive shifting in young children
Authors: Moriguchi Yusuke , Hiraki Kazuo
Published: March 2009

Cognitive shifting is the ability to adapt to changes in the environment. Extensive research has revealed that the prefrontal cortex plays an important role in cognitive shifting. Adult neuroimaging studies have shown that the inferior prefrontal cortex is activated during cognitive shifting tasks. Developmental studies have shown that cognitive shifting changes significantly during preschool years. It is known that 3-year-old children often perseverate to previous mental sets, whereas 5-year-old children do not. Developmental psychologists assume that maturation of the prefrontal cortex plays an essential role in the development of shifting; however, direct supporting evidence is lacking. We used near-infrared spectroscopy and showed that inferior prefrontal activation is associated with successful shifting in young children. We also showed that even preschool children display adult-like inferior prefrontal activation during a simple cognitive shifting task. This report demonstrates the neural origins of cognitive shifting in young children. These results have the potential to contribute to our understanding of cognitive and brain development in both typically and atypically developed children.
Alkyl hydroperoxide reductase has a role in oxidative stress resistance and in modulating changes in cell-surface properties in Azospirillum brasilense Sp245
Authors: Wasim Mariam , Bible Amber N. , Xie Zhihong , Alexandre Gladys
Published: March 2009

AnahpCmutant derivative ofAzospirillum brasilenseSp245 (strain SK586) that encodes an alkyl hydroperoxide reductase was found to be more sensitive to oxidative stress caused by organic hydroperoxides compared with the wild-type. In addition, theahpCmutant strain had multiple defects in a large array of cellular functions that were consistent with alteration of cell-surface properties, such as cell morphology in stationary phase, Calcofluor White-, Congo Red- and lectin-binding abilities, as well as cell-to-cell aggregation and flocculation. All phenotypes of theahpCmutant were complemented byin transexpression of AhpC, and overexpression of AhpC in the wild-type strain was found to affect the same set of phenotypes, suggesting that the pleiotropic effects were caused by theahpCmutation. SK586 was also found to be fully motile, but it lost motility at a higher rate than the wild-type during growth, such that most SK586 cells were non-motile in stationary phase. Despite these defects, the mutant did not differ from the wild-type in short-term colonization of sterile wheat roots when inoculated alone, and in competition with the wild-type strain; this implied that AhpC activity may not endow the cells with a competitive advantage in colonization under these conditions. Although the exact function of AhpC in affecting these phenotypes remains to be determined, changes in cell morphology, surface properties, cell-to-cell aggregation and flocculation are common adaptive responses to various stresses in bacteria, and the data obtained here suggest that AhpC contributes to modulating such stress responses inA. brasilense.
Activation of the eis gene in a W-Beijing strain of Mycobacterium tuberculosis correlates with increased SigA levels and enhanced intracellular growth
Authors: Wu Shiping , Barnes Peter F. , Samten Buka , Pang Xiuhua , Rodrigue Sébastien , Ghanny Saleena , Soteropoulos Patricia , Gaudreau Luc , Howard Susan T.
Published: March 2009

There is growing evidence that strains ofMycobacterium tuberculosisdiffer in pathogenicity and transmissibility, but little is understood about the contributory factors. We have previously shown that increased expression of the principal sigma factor, SigA, mediates the capacity ofM. tuberculosisstrain 210 to grow more rapidly in human monocytes, compared with other strains. Strain 210 is part of the widespread W-Beijing family ofM. tuberculosisstrains and includes clinical isolate TB294. To identify genes that respond to changes in SigA levels and that might enhance intracellular growth, we examined RNA and protein expression patterns in TB294-pSigA, a recombinant strain of TB294 that overexpressessigAfrom a multicopy plasmid. Lysates from broth-grown cultures of TB294-pSigA contained high levels of Eis, a protein known to modulate host–pathogen interactions. DNA microarray analysis indicated that theeisgene, Rv2416c, was expressed at levels in TB294-pSigA 40-fold higher than in the vector control strain TB294-pCV, during growth in the human monocyte cell line MonoMac6. Other genes with elevated expression in TB294-pSigA showed much smaller changes from TB294-pCV, and the majority of genes with expression differences between the two strains had reduced expression in TB294-pSigA, including an unexpected number of genes associated with the DNA-damage response. Real-time PCR analyses confirmed thateiswas expressed at very high levels in TB294-pSigA in monocytes as well as in broth culture, and further revealed that, likesigA,eiswas also more highly expressed in wild-type TB294 than in the laboratory strain H37Rv, during growth in monocytes. These findings suggested an association between increased SigA levels andeisactivation, and results of chromatin immunoprecipitation confirmed that SigA binds theeispromoter in live TB294 cells. Deletion ofeisreduced growth of TB294 in monocytes, and complementation ofeisreversed this effect. We conclude that SigA regulateseis, that there is a direct correlation between upregulation of SigA and high expression levels ofeis, and thateiscontributes to the enhanced capacity of a clinical isolate ofM. tuberculosisstrain 210 to grow in monocytes.
Comparative expression of syndecan‐1 and Ki‐67 in peripheral and desmoplastic ameloblastomas and ameloblastic carcinoma
Authors: Bologna‐Molina Ronell , Mosqueda‐Taylor Adalberto , Lopez‐Corella Eduardo , De Almeida Oslei Paes , Carrasco‐Daza Daniel , Farfán‐Morales José E. , Molina‐Frechero Nelly , Damián‐Matsumura Pablo
Published: March 2009

The aims of the present study were to examine whether the pattern of syndecan‐1 expression correlates with cellular proliferation index in desmoplastic ameloblastomas (DA), peripheral ameloblastomas (PA) and ameloblastic carcinomas (AC), and to compare with that previously reported for solid (SA) and unicystic (UA) variants of ameloblastoma. Immunohistochemistry was performed for syndecan‐1 and Ki‐67 in seven ameloblastomas (four DA and three PA) and three AC. Expression of syndecan‐1 was related to the histological subtype of tumors and, in the case of malignancy, to lower expression levels observed in AC (22.5%) than in PA (47.5%) or DA (77.5%) (P < 0.05). Syndecan‐1 expression correlated inversely with Ki‐67 proliferative index: the expression was lower in both types of ameloblastomas (1.5% in DA and 6.4% in PA) than in AC (41.2%; P < 0.05). The present results suggest that the decrease in syndecan‐1 expression and increase in the Ki‐67 index observed in AC is in accordance with its higher aggressiveness as compared to the rare DA and PA. Interestingly, DA had a lower proliferation index as well as the highest levels of syndecan‐1 expression. These data suggest that DA differ from the other types of intraosseous ameloblastomas but more studies are necessary to better understand the role of this protein as a marker in the biological behavior of the epithelial odontogenic neoplasms.
Intralesional recombinant α‐interferon for localized prostate cancer: a pilot study with follow‐up of >10 years
Authors: Emerson Laurel , Morales Alvaro
Published: March 2009

OBJECTIVE

To report the long‐term results of the intralesional administration of an immune modifier, interferon‐α (IFN‐α) in men with localized prostate cancer, providing a method for drug delivery within the gland under ultrasonographic control.

PATIENTS AND METHODS

Ten men with localized prostate cancer participated in a study involving the intraprostatic injection of IFN‐α, weekly for 5 weeks. Prostate biopsies were taken and prostate‐specific antigen (PSA) levels were measured bi‐annually or until the men had an alternative treatment.

RESULTS

The pretreatment mean Gleason score was 7 and the mean PSA level 11 ng/mL. Biopsies after treatment were negative in three patients. Of the remaining seven, six chose to continue watchful waiting. With time, five went on to alternative treatment; one had radical prostatectomy (at 3 months), two had external beam radiotherapy (at 3 and 6 months), and two had androgen suppression (at 3 and 24 months). Of the three men with initial negative biopsies, one died from unrelated causes 13 years later, with an undetectable PSA level; the second remains asymptomatic 13 years later but has an elevated PSA level. The last patient has a low (<4 ng/mL) PSA level, negative biopsies and had ‘no cancer’ in a resection specimen, 64 months after treatment. These two men remain under active surveillance with no intervention.

CONCLUSIONS

After delivery of IFN‐α directly into the prostate gland, and a long follow‐up, it appears that there was some antitumour activity in some patients. The doses used were small and the schedule of administration short. Further evaluation of this, and other agents alone and in combination, might be worthwhile.
Bladder cancer survivals in New South Wales, Australia: why do women have poorer survival than men?
Authors: Tracey Elizabeth , Roder David , Luke Colin , Bishop James
Published: March 2009

OBJECTIVE

To investigate factors that most influenced survival from bladder cancer in New South Wales, Australia (NSW) and to consider the impact of changes in coding practices on the reporting the of bladder cancer outcomes.

PATIENTS AND METHODS

All NSW cases of bladder cancer diagnosed between 1980 and 2003 were followed to the end of 2004 (17 923 cases). Survival analysis was undertaken using Kaplan–Meier unadjusted disease‐specific survival and adjusted disease‐specific survival using Cox proportional hazards regression modelling. This analysis was unique in that it modelled the effect of sex, age, country of birth, socio‐economic status (SES), histological type, extent of disease and period of diagnosis on survival from bladder cancer in NSW.

RESULTS

After adjusting for sex, age, extent of disease, SES, period of diagnosis and histological type, the likelihood of death was 11% (95% confidence interval, CI 5–18%) higher in females than in males, with case fatality most influenced by age at diagnosis, extent of disease, and histological type. When the analysis was repeated for cases with a method 6 (i.e. coding undertaken in the registry after examination of the pathology report, which would enhance accuracy), the likelihood of death was 13% (95% CI 5–21%) higher in females than in males.

CONCLUSIONS

The NSW analysis controls for variability in coding, extent of disease at diagnosis and histological type of cancer. The analysis shows significantly lower survival from bladder cancer in NSW women compared with men, with no improvement in survival from 1980 to 2003. Possible reasons for the lower survivals in women, the lack of improvement in survival and coding differences in jurisdictions are discussed.
Relationship between special abilities and autistic‐like traits in a large population‐based sample of 8‐year‐olds
Authors: Vital Pedro M. , Ronald Angelica , Wallace Gregory L. , Happé Francesca
Published: March 2009

Background:  The raised incidence of special abilities or ‘savant skills’ among individuals with autism spectrum disorders (ASD) relative to other developmental disorders suggests an association between the traits characteristic of ASD and special abilities. The purpose of this study was to investigate the association between special abilities and ASD‐like traits.

Methods:  This study compared the scores of 6,426 8‐year‐olds with and without parent‐reported special abilities on a screening questionnaire for ASD‐like traits in three areas: social interaction, communication, and restricted and repetitive behaviours and interests. Measures of IQ, sex, and socioeconomic status (SES) were also compared.

Results:  From parent report, children with special abilities showed significantly more ASD‐like traits than those without such abilities. General intelligence did not mediate this relationship: IQ was found to be positively associated with ability, but negatively associated with ASD‐like traits. Special abilities were more strongly associated with restricted/repetitive characteristics than with social or communication traits.

Conclusions:  Results support the association between special abilities and ASD‐like traits, and expand it to traits in the general population. The type of nonsocial traits most strongly associated with parental reports of special abilities suggests a link to a featural information processing style, or ‘weak central coherence’.
Digestive system of larval black flies (Diptera: Simuliidae): structure and phylogeny
Authors: Kim Sam‐Kyu , Adler Peter H.
Published: March 2009

Abstract. Larval gut characters of 45 species of black flies, representing 17 subgenera and 15 genera, were studied for their utility in taxon diagnosis and phylogenetic inference. Phase‐contrast and scanning electron microscopy revealed a wealth of new characters in the esophageal armature of the foregut. Larval gut morphology, particularly characters of the esophageal armature, varied significantly among taxa, permitting generic diagnoses. A cladogram inferred from 13 gut characters supported a sister‐group relationship between Parasimulium and the remaining simuliids, but did not show a strong phylogenetic signal for the current, well‐supported concept of tribal level monophyly.
Commensalism used by freshwater crayfish species to survive drying in seasonal habitats
Authors: Johnston Kerrylyn , Robson Belinda J.
Published: March 2009

Abstract. Gramastacus insolitus is a very small non‐burrowing Australian freshwater crayfish with a restricted distribution, occurring almost exclusively in seasonal habitats throughout its range. It is listed as a threatened species but its strategy for surviving dry periods was unknown. Eight seasonal surveys of crayfish distribution showed that members of G. insolitus were never found at sites that were outside the distribution of two larger burrowing freshwater crayfish species, Geocharax falcata and Cherax destructor. Excavation of 80 burrows of members of G. falcata and C. destructor in three different seasonal habitats in the Grampians National Park, Victoria, Australia, revealed that individuals of G. insolitus found refuge from drying by estivating in cracks and shallow depressions at the side of the main burrow tunnels constructed by larger species. Members of G. insolitus were not found estivating at the surface, such as under fallen wood, nor was it usually found in crayfish burrows unoccupied by the host crayfish. This study indicates that members of G. insolitus are commensal upon larger crayfish species, using their burrows to survive the seasonal drying of their habitat. Conservation strategies for populations of G. insolitus will need to consider co‐existing species of burrowing crayfish.
High Self‐Reported Prevalence of Diabetes Mellitus, Heart Disease, and Stroke in 11 Counties of Rural Appalachian Ohio
Authors: Schwartz Frank , Ruhil Anirundth , Denham Sharon , Shubrook Jay , Simpson Chris , Boyd Sara L.
Published: March 2009

ABSTRACT: 
Context/Purpose: There is an epidemic of obesity and diabetes in the United States, especially in economically at‐risk populations such as rural Appalachia. This survey determined the self‐reported prevalence of obesity, diabetes mellitus, and associated macrovascular complications in 11 rural counties of Appalachian Ohio. The impacts of lifestyle, cardiovascular risk factors, income, and access to medical care were also determined. Methods: A telephone survey identical to the 2004 Behavioral Risk Factor Surveillance System (BRFSS) survey was conducted. Surveys were collected from 3,927 randomly selected residents 18 years of age and older in 11 counties of Appalachian Ohio and compared to published aggregate Ohio and national 2004 BRFSS data. Findings: The self‐reported prevalence of diabetes (11.3%) was markedly higher in Appalachian Ohio counties surveyed compared to aggregate Ohio (7.8%) or national (7.2%) 2004 BRFSS data (P < .044). The prevalence of heart disease (7.6%) and stroke (4.1%) in these counties was slightly higher than aggregate Ohio or national 2004 BRFSS data. In persons with diabetes, the prevalence of heart disease was 2‐fold higher (20.0%) and stroke 3‐fold higher (11.4%) than among nondiabetics (P < .042) in the region and higher than aggregate Ohio and National 2004 BRFSS data. Lower‐income levels and decreased access to medications and glucose monitoring supplies correlated with the increased risk for cardiovascular complications in this rural population (P < .042). Conclusion: The self‐reported prevalence of diabetes mellitus and its associated macrovascular complications are much higher in rural Appalachian Ohio compared to aggregate Ohio and National 2004 BRFSS data.
Specification of Spatial Relationships in Directed Graphs of Cell Signaling Networks
Authors: Lipshtat Azi , Neves Susana R. , Iyengar Ravi
Published: March 2009

Graph theory provides a useful and powerful tool for the analysis of cellular signaling networks. Intracellular components such as cytoplasmic signaling proteins, transcription factors, and genes are connected by links, representing various types of chemical interactions that result in functional consequences. However, these graphs lack important information regarding the spatial distribution of cellular components. The ability of two cellular components to interact depends not only on their mutual chemical affinity but also on colocalization to the same subcellular region. Localization of components is often used as a regulatory mechanism to achieve specific effects in response to different receptor signals. Here we describe an approach for incorporating spatial distribution into graphs and for the development of mixed graphs where links are specified by mutual chemical affinity as well as colocalization. We suggest that such mixed graphs will provide more accurate descriptions of functional cellular networks and their regulatory capabilities and aid in the development of large‐scale predictive models of cellular behavior.
INTEGRATED PRODUCTION AND THE INVESTMENT–UNCERTAINTY RELATIONSHIP
Authors: Tsai Yingyi , Wu Ching‐tang
Published: March 2009

This paper studies the role of production mode in determining the effects of an increase in uncertainty on the choice of investment outlay. In a continuous‐time model of optimal capital investment with innovative R&D under demand uncertainty, we show that investments in both capital and innovative research decrease with an increase in uncertainty, and that such investments rise with the level of primary demand. Our result sheds light on the mode of production as a source of the negative investment–uncertainty relationship.
Switching between transient and sustained signalling at the rod bipolar‐AII amacrine cell synapse of the mouse retina
Authors: Snellman Josefin , Zenisek David , Nawy Scott
Published: March 2009

At conventional synapses, invasion of an action potential into the presynaptic terminal produces a rapid Ca2+ influx and ultimately the release of synaptic vesicles. However, retinal rod bipolar cells (RBCs) generally do not produce action potentials, and the rate of depolarization of the axon terminal is instead governed by the rate of rise of the light response, which can be quite slow. Using paired whole‐cell recordings, we measured the behaviour of the RBC‐AII amacrine cell synapse while simulating light‐induced depolarizations either by slowly ramping the RBC voltage or by depolarizing the RBC with the mGluR6 receptor antagonist (R,S)‐α‐cyclopropyl‐4‐phosphonophenylglycine (CPPG). Both voltage ramps and CPPG evoked slow activation of presynaptic Ca2+ currents and severely attenuated the early, transient component of the AII EPSC compared with voltage steps. We also found that the duration of the transient component was limited in time, and this limitation could not be explained by vesicle depletion, inhibitory feedback, or proton inhibition. Limiting the duration of the fast transient insures the availability of readily releasable vesicles to support a second, sustained component of release. The mGluR6 pathway modulator cGMP sped the rate of RBC depolarization in response to puffs of CPPG and consequently potentiated the transient component of the EPSC at the expense of the sustained component. We conclude that the rod bipolar cell is capable of both transient and sustained signalling, and modulation of the mGluR6 pathway by cGMP allows the RBC to switch between these two time courses of transmitter release.
Vortex-Induced Vibration and Coincident Current Velocity Profiles for a Deepwater Drilling Riser
Authors: Srivilairit T. , Manuel L.
Published: March 2009

The objective of this study is to use full-scale field data on current velocities and riser motions to better understand the behavior of deepwater drilling risers. The data are comprised of riser accelerations and coincident current velocity profiles from the monitoring of vortex-induced vibration (VIV) of a drilling riser located at a 1000 m water depth site. Proper orthogonal decomposition (POD), an efficient numerical technique for characterizing the spatial coherence in a random field, is employed here to identify energetic current profiles. The accuracy resulting from the use of only a limited number of the most important POD modes is studied by comparing measured current velocity profiles with those reconstructed based on a reduced-order truncation. In addition to studying current velocity profiles, riser acceleration data from this deepwater drilling riser are also analyzed. In order to analyze the VIV response of this riser, in-line and cross-flow motions in different data segments are studied. Again, empirical POD procedures are employed—this time to derive energetic spatial vibration modes defining the riser motion. Importantly, these modes are identified without the need for either an analytical/computational model of the riser or any physical dimensions and material properties; instead, they are derived exclusively using the field data. Relationships between riser response and coincident current velocity profiles are investigated, especially for those data segments associated with observed lock-in response.
Comprehensive fluence model for absolute portal dose image prediction
Authors: Chytyk K. , McCurdy B. M. C.
Published: March 2009

Amorphous silicon electronic portal imaging devices (EPIDs) continue to be investigated as treatment verification tools, with a particular focus on intensity modulated radiation therapy (IMRT). This verification could be accomplished through a comparison of measured portal images to predicted portal dose images. A general fluence determination tailored to portal dose image prediction would be a great asset in order to model the complex modulation of IMRT. A proposed physics‐based parameter fluence model was commissioned by matching predicted EPID images to corresponding measured EPID images of multileaf collimator (MLC) defined fields. The two‐source fluence model was composed of a focal Gaussian and an extrafocal Gaussian‐like source. Specific aspects of the MLC and secondary collimators were also modeled (e.g., jaw and MLC transmission factors, MLC rounded leaf tips, tongue and groove effect, interleaf leakage, and leaf offsets). Several unique aspects of the model were developed based on the results of detailed Monte Carlo simulations of the linear accelerator including (1) use of a non‐Gaussian extrafocal fluence source function, (2) separate energy spectra used for focal and extrafocal fluence, and (3) different off‐axis energy spectra softening used for focal and extrafocal fluences. The predicted energy fluence was then convolved with Monte Carlo generated, EPID‐specific dose kernels to convert incident fluence to dose delivered to the EPID. Measured EPID data were obtained with an EPID for various MLC‐defined fields (from over a range of source‐to‐detector distances. These measured profiles were used to determine the fluence model parameters in a process analogous to the commissioning of a treatment planning system. The resulting model was tested on 20 clinical IMRT plans, including ten prostate and ten oropharyngeal cases. The model predicted the open‐field profiles within 2%, , while a mean of 96.6% of pixels over all IMRT fields was in agreement with the 2%, criteria. This model demonstrates accuracy commensurate to existing methods for IMRT pretreatment verification with portal dose image prediction of complex clinical examples (, ).
Characteristics of elliptical sources in BEAMnrc Monte Carlo system: Implementation and application
Authors: Kim Sangroh
Published: March 2009

Recently, several papers noticed that the electron focal spot of a linear accelerator (linac) could be elliptical which would cause dosimetric discrepancies between measurements and Monte Carlo simulations. To resolve the mismatch, two elliptical source models were developed in BEAMnrc code. The first was a parallel beam elliptical source with uniform distribution where the shape of the source was primarily considered. The other was a parallel beam elliptical source with Gaussian distribution whose source distribution follows the normal distribution. To validate the elliptical source models, uniform and Gaussian electron beams were impinged on a thin air target. Both models successfully reproduced the elliptical shapes and source distributions. Then, this study investigated the characteristics of the elliptical Gaussian source for a 6 MV photon beam in a Varian 21EX linac. The linac head model was implemented in the BEAMnrc/EGSnrc system and commissioned by comparing the lateral and depth dose profiles to the ion chamber measurements acquired from the annual quality assurance (QA). It was found that the circular Gaussian beam with 6 MeV/0.2 cm full width half maximum (FWHM) produces the best matches to the QA data. To explore the characteristics of the elliptical Gaussian source, this study employed an elliptical Gaussian electron source with 0.1 cm FWHM in the axis and 0.2 cm FWHM in the axis which was incident on the target of the linac head. Two circular Gaussian beams with 0.1 and 0.2 cm FWHM were employed to compare the differences between circular and elliptical sources. For all the sources, planar and energy fluences were acquired and analyzed. This study also compared the lateral and depth dose profiles in a water phantom by using a DOSXYZnrc user code. In results, a constricted shoulder effect was observed in both planar and energy fluence plots when the FWHM value was increased and the field size is larger than . The same effect was also noticed in the lateral dose profiles, while the depth dose profile did not vary much.