Modeling and prediction of surgical procedure times

Accurate prediction of medical operation times is of crucial importance for cost efficient operation room planning in hospitals. This paper investigates the possible dependence of procedure times on surgeon factors like age, experience, gender, and team composition. The effect of these factors is estimated for over 30 different types of medical operations in two hospitals, by means of ANOVA models for logarithmic case durations. The estimation data set contains about 30,000 observations from 2005 till 2008. The relevance of surgeon factors depends on the type of operation. The factors found most often to be significant are team composition, experience, and daytime. Contrary to widespread opinions among surgeons, gender has nearly never a significant effect. By incorporating surgeon factors, the accuracy of out-of-sample prediction of case durations of about 1,250 surgical operations in 2009 is improved by up to more than 15 percent as compared to current planning procedures.planning;ANOVA model;European hospital;current procedure terminology (CPT);health care management;lognormal distribution;operation room;surgeon factors

Night temperature and number of nodes and flowering of the main stem of glasshouse cucumber (Cucumis sativus L.).

Plants of the cucumber cv. Farbio (all-female) were planted on 13 or 27 December, 10 or 24 January and grown at 3 minimum night temperatures, 12, 16 or 20 deg C from planting until 1 April. Node number/stem increased as the night temperature fell. Internodes were longer with later planting and on plants on inner rather than outer rows; these responses could not be related to light intensity alone. The number of flowers/stem was determined by the number of nodes bearing flowers and the number of flowers/node. More flowers/node occurred towards the top of the plant and late planting increased flowering at all nodes; the night temperature had little effect on numbers but these were highest at 16 deg . Earliness to flower of the first flowers/axil and the intensity of flowering both rose with temperature. Flowering was delayed only slightly by later planting. (Abstract retrieved from CAB Abstracts by CABI’s permission

Night temperature and flower abortion of glasshouse cucumber (Cucumis sativus L.).

Plants of the gynaecious cucumber cv. Farbio were planted under glass, about 30 days after sowing, on 13 and 27 December and on 10 and 24 January. Night temperatures of 12, 16 and 20 deg C were compared until 1 April, the day temperature being 21-27 deg . Only 835 of 3600 flowers aborted shortly after opening. The later planted crops showed less abortion than earlier planted ones and the lower the night temperature the higher was the level of abortion. Abortion of the second and third flowers in an axil accounted for 60% of the total, regardless of night temperature. Fruits were picked every 5 days; those with the longest hanging time (i.e. slowest growth) were found primarily in axils just below axils in which all flowers had aborted. Such fruits are known to have a reduced shelf life [see HcA 50, 7105] and quality could thus be controlled to some extent by selective thinning of fruit in these axils. (Abstract retrieved from CAB Abstracts by CABI’s permission

Night temperature and fruiting of glasshouse cucumber (Cucumis sativus L.).

Cucumber seedlings, cv. Farbio, planted in the greenhouse on 13 or 27 December or 10 or 24 January, were grown at 21-27 deg C day temperature and 12, 16 or 20 deg night temperatures until 1 April. Later planting produced more fruit than early planting. Night temperature had only a slight effect on fruit numbers/stem, but there was an optimum near 16 deg . The rate of fruit production between 12 and 20 deg was similar, but increased slightly with later planting. Production started earlier with higher night temperature and later planting. Fruit growth was not affected markedly by night temperature and fruit weight at harvest increased with season but was not dependent on the treatments. Fruit length was also independent of night temperature or planting date. (Abstract retrieved from CAB Abstracts by CABI’s permission

Pointing and voicing in deictic expressions

Contains fulltext : 5651.pdf (publisher's version ) (Open Access

Enten van paprikaplanten ; resultaten van proeven uit 1994 en 1995

Sinds vele decennia worden glasgroentegewassen geënt op onderstammen, die een bepaalde resistentie tegen bodemziekten hebben. Als geënt wordt op een gedomesticeerd ras van dezelfde plantensoort kan extra groeikracht en productie verkregen worden. In een verkennend onderzoek zijn in 1994 en 1995 ervaringen met het enten van paprikaplanten opgedaan, waarin tevens de productie en de kwaliteit van de vruchten bepaald is. Dit rapport geeft een beknopt overzicht van de resultaten van de verrichte proeven