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BackgroundDistichiasis, an ocular disorder in which aberrant cilia (eyelashes) grow from the opening of the Meibomian glands of the eyelid, has been reported in Friesian horses. These misplaced cilia can cause discomfort, chronic keratitis, and corneal ulceration, potentially impacting vision due to corneal fibrosis, or, if secondary infection occurs, may lead to loss of the eye. Friesian horses represent the vast majority of reported cases of equine distichiasis, and as the breed is known to be affected with inherited monogenic disorders, this condition was hypothesized to be a simply inherited Mendelian trait.ResultsA genome wide association study (GWAS) was performed using the Axiom 670 k Equine Genotyping array (MNEc670k) utilizing 14 cases and 38 controls phenotyped for distichiasis. An additive single locus mixed linear model (EMMAX) approach identified a 1.83 Mb locus on ECA5 and a 1.34 Mb locus on ECA13 that reached genome-wide significance (pcorrected = 0.016 and 0.032, respectively). Only the locus on ECA13 withstood replication testing (p = 1.6 × 10- 5, cases: n = 5 and controls: n = 37). A 371 kb run of homozygosity (ROH) on ECA13 was found in 13 of the 14 cases, providing evidence for a recessive mode of inheritance. Haplotype analysis (hapQTL) narrowed the region of association on ECA13 to 163 kb. Whole-genome sequencing data from 3 cases and 2 controls identified a 16 kb deletion within the ECA13 associated haplotype (ECA13:g.178714_195130del). Functional annotation data supports a tissue-specific regulatory role of this locus. This deletion was associated with distichiasis, as 18 of the 19 cases were homozygous (p = 4.8 × 10- 13). Genotyping the deletion in 955 horses from 54 different breeds identified the deletion in only 11 non-Friesians, all of which were carriers, suggesting that this could be causal for this Friesian disorder.ConclusionsThis study identified a 16 kb deletion on ECA13 in an intergenic region that was associated with distichiasis in Friesian horses. Further functional analysis in relevant tissues from cases and controls will help to clarify the precise role of this deletion in normal and abnormal eyelash development and investigate the hypothesis of incomplete penetrance.

Previous research conducted by the Construction Industry Institute (CII) and others has demonstrated the value of front-end planning as it impacts project success. A recently completed research project funded by CII, described in this paper, examines ways to improve information flow through the front-end planning process. This paper focuses on one specific objective of this research project, namely to isolate and closely examine the information critical activities within the front-end planning process. The front-end planning process was carefully diagrammed as consisting of 33 distinct activities, each with its own information flow entities and interactions. Fifty-one questionnaire survey forms were analyzed to obtain data for the 33 activities that included activity duration, resources expended, and the extent to which information was available to perform the activity. The 51 projects were then grouped according to survey respondents' perceptions as to whether the front-end planning process was executed more or less effectively. An analysis of the data concluded with a degree of statistical significance that seven of the 33 activities have some impact on achieving project success. In addition, statistically significant differences were uncovered with respect to the extent that information was available for selected activities, and survey respondent perceptions with respect to how efficiently the activity was performed. These seven activities are involved in planning the following areas: Public relations, start up, quality and safety, the project execution plan, and project scope definition. Other activities for which information was frequently not available and/or for which considerable resources were expended relate to preliminary cost estimating and the development of a funding plan. A second survey form was forwarded to the original survey participants to obtain more specific information with respect to the information categories and interfaces associated with the critical activities that were identified in the original survey. This survey indicated problem areas including inadequate scope definition, risk identification and mitigation, minimal resource allocation for task execution, unclear definitions of roles and responsibilities, and ineffective external communication mechanisms. DOI: 10.1061/(ASCE)0742-597X(2008)24:2(66) CE Database subject headings: Planning; Construction Industry; Information management; Project management.

This study presents a new methodology for evaluating at-completion project performance status. This new procedure uses the concept of stochastic S curves (SS curves) to determine forecasted project estimates as an alternative to using deterministic S curves and traditional forecasting methods. A simulation approach is used for generating the stochastic S curves, and it is based on the defined variability in duration and cost of the individual activities within the process. Stochastic S curves provide probability distributions for the budget and time values required to complete the project at every selected point of intermediate completion. Final project performance is determined by comparing the planned budget and project duration, with the expected forecasted final cost and elapsed time, respectively. The SS-curve methodology permits objective evaluation of project performance without the limitations inherent in a deterministic approach. The probabilistic characteristics of this approach enable users to more accurately determine at-completion cost and duration variations and evaluate the performance improvement of proposed corrective actions. CE Database subject headings: Project management; Scheduling; Monte Carlo method; Simulation; Cost control; Forecasting; Performance evaluation.