ESTIMATION OF WATER TEMPERATURE EXCEEDANCE PROBABILITIES USING THERMO-HYDRODYNAMIC MODELING1

ABSTRACT: A continuous simulation approach is proposed for estimating water temperature exceedance probabilities using thermo-hydrodynamic modeling. The approach uses (1) a deterministic unsteady flow and heat transport model, (2) continuous hydrological and meteorological data for a long historical period, and (3) synthetic records of tributary water temperatures and other model inputs. Representative historical records of streamflow, air temperatures, and other hydrometeorological variables are obtained from nearby gages. Stochastic modeling methods are used to construct synthetic records for other model inputs, including inflow water temperatures. An application of this deterministic-stochastic approach is presented for a complex waterway in northeastern Illinois with heat discharges from several power plants and wastewater treatment plants. Statistical results from the continuous simulations are compared to results obtained from traditional event simulations. The application illustrates the information that engineers and biologists can obtain for (1) evaluating compliance with water temperature standards, and (2) assessing the effect of water temperatures on aquatic habitat.     

Ontogeny of fetal liver glucose-6-phosphatase activity

A reliable and sensitive microassay for the measurement of liver glucose-6-phosphatase is described. Human fetal liver was assayed for glucose-6-phosphatase activity from 7.5 to 24 weeks of gestation and was found to have a mean activity of 2.11 nmol per min per mg of protein. This was approximately 30 per cent of the postnatal controls assayed by the same method, but there was no evidence of a change in activity during the gestational period examined. If fetal liver tissue can be reliably obtained, it may be possible to determine a deficiency of glucose-6-phosphatase in fetuses who are at risk.     

Polyandry in the genus Apis, particularly Apis andreniformis

Using four polymorphic microsatellite loci, we found that four Apis andreniformis queens collected in Thailand each mated at least 10–20 times, producing an average relatedness, g _ww, of workers of 0.30 ± 0.007, and an average effective number of matings of 9.1 ± 2.2. The degrees of polyandry and intra-colonial genetic relatedness in A. andreniformis are similar to those in A. mellifera, slightly more than in A. florea, and up to 6 times less than in A. dorsata. We argue that while presently favoured hypotheses for the evolution of polyandry in monogynous social insects may adequately explain the evolution of up to five or six matings, they are inadequate to explain the extreme polyandry (10–60 matings) observed in Apis. One alternative possibility is that colony fitness is a non-additive function of the fitness of individual subfamilies. Such behavioral over-dominance may mean that queen fitness is increased by high levels of polyandry, which increase the probability of desirable combinations of worker genotypes occurring in one colony. The special attributes of honey bees which may lead to behavioral over-dominance include colony aggregation (which may increase the incidence of disease), and frequent long-distance migration. Received: 8 May 1996/Accepted after revision: 9 August 1996     

Molecular systematic and phylogenetic assessment of 34 calanoid copepod species of the Calanidae and Clausocalanidae

DNA sequences for a 639 bp region of mitochondrial cytochrome oxidase I (mtCOI) were determined for 34 species of ten genera in two families of calanoid copepods, including: Calanoides, Cosmocalanus, Meoscalanus, Nannocalanus, Neocalanus, and Undinula (family Calanidae); and Clausocalanus, Ctenocalanus, Drepanopus, and Pseudocalanus (family Clausocalanidae). MtCOI gene sequences proved to be diagnostic molecular systematic characters for accurate identification and discrimination of the species. Levels of mtCOI variation within species (range: 1-4%) were significantly less than those between species (9-25%). Higher levels of intraspecific variation (>2%) usually resulted from comparisons between ecologically distinct or geographically isolated populations. MtCOI sequence variation resolved evolutionary relationships among species of Clausocalanus, Neocalanus, and Pseudocalanus, although there was evidence of saturation at some variable sites. Phylogenetic relationships among 11 copepod genera (adding Calanus to the list above) were reconstructed using a 660 bp region of nuclear small-subunit 18S rRNA, a slowly evolving gene that showed no variability within a species and differed by <1-6% among the genera. The 18S rRNA molecular phylogeny was consistent with the accepted limits of the Calanidae and Clausocalanidae and clearly resolved relationships among genera within each family. This molecular systematic and phylogenetic study was part of the ZooGene project, an international partnership to create a DNA sequence database as a tool for uniform, molecularly based species identification of planktonic calanoid copepods and euphausiids.     

Alpha-fetoprotein and ultrasound scanning in the prenatal diagnosis of Turner's Syndrome

Based on data from 5 cases of fetal cystic hygroma (4 cases of Turner's Syndrome and one case of Trisomy 18) and one case of Down's Syndrome with severe subcutaneous oedema, it is concluded that amniotic fluid alpha-fetoprotein (AFP) is normal or only slightly elevated in such cases whereas AFP in fluid from the cystic structures is very high. Reported high values of ‘amniotic fluid’ AFP are therefore likely to have been obtained from fluids accidentally drawn from the cystic structures. Fluids from the two sources cannot be distinguished from each other visually. In support of this theory is that the maternal serum AFP was found to be normal in all cases where investigated. In the diagnosis of cystic hygromata detailed ultrasound scanning will reveal the correct diagnosis.     

Task specialization in a wild bee,Apis florea (Hymenoptera: Apidae), revealed by RFLP banding

Workers in a wild in situ colony of the dwarf honey bee, Apis florea, were observed undertaking the following behavior: liquid foraging, pollen foraging, guarding, stinging, fanning and wagging abdomen. Bees of each behavioral class were separately collected and frozen. Collections were made over a period of 10 days. Random samples of brood and workers were also collected. DNA was extracted from each bee and fingerprinted using a probe of unknown sequence obtained from an A. mellifera genomic library. Patterns of fingerprints (Fig. 1) were dissimilar among behavioral classes (Tables 1 and 2), strongly suggesting a genetic component to division of labor in this species. This result supports similar findings in A. mellifera in a species that is not troubled by many of the experimental difficulties inherent in A. mellifera. Correspondence to: B.P. Oldroyd     

Constitutive or induced defences - how does <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> defend itself from larval feeding?

Summary. Following herbivory, induced responses involving plant secondary metabolites have been reported in a number of tree species. Although a wide range of plant secondary metabolites appear to operate as constitutive plant defences in trees belonging to the Eucalyptus genus, no induced responses have as yet been reported following foliar-chewing insect damage. We empirically tested whether branch defoliation (artificial and larval) of 2-year-old Eucalyptus globulus Labill. trees altered the abundance of specific plant secondary metabolites immediately (3 months after initial larval feeding) and 8 months after the cessation of larval feeding. Metabolites assayed, included essential oils, polyphenolic groups and foliar wax compounds and in all cases their abundance was not significantly altered by defoliation. However, the level of foliar tannins after 3 months of larval feeding did display a trend that suggested elevated levels as the result of defoliation, though this trend was not evident 8 months later, indicating that, if real, the response was a rapid and not a delayed induced response. The level of foliar tannins was also negatively correlated to both average larval survival and average percentage branch defoliation, suggesting that foliar tannins may operate as toxins and/or anti-feedants to M. privata larval feeding.     

Effect of tidal submersion on lysozyme activity in Mytilus edulis and Tellina tenuis

Changes in mean style weight and in lysozyme activity of the style, digestive gland, gill and mantle of Mytilus edulis and Tellina tenuis from the Clyde Sea area, Scotland, were investigated over tidal cycles in March and August, 1981. For M. edulis, significant changes occurred in the style weight, style lysozyme activity and digestive gland lysozyme activity during a 22 h period. These appear to be related to a diurnal cycle rather than a tidal cycle. Changes in the weight of the style of M. edulis may be caused by dissolution during feeding, and style lysozyme may be secreted independently of the style matrix. The activity of lysozyme in T. tenuis is unaffected by the tide, suggesting that this intertidal bivalve can feed throughout the tidal cycle.     

An Urban Diffusion Simulation Model For Carbon Monoxide

A relatively simple Gaussian-type diffusion simulation model for calculating urban carbon monoxide (CO) concentrations as a function of local meteorology and the distribution of traffic is described. The model can be used in two ways: (1) in the synoptic mode, in which hourly concentrations at one or many receptor points are calculated from historical or forecast traffic and meteorological data; and (2) in the climatological mode, in which concentration frequency distributions are calculated on the basis of long-term sequences of input data. For model evaluation purposes, an extensive field study involving meteorological and air-quality measurements was conducted during November-December 1970 in San Jose, Calif., which has an automated network to provide traffic data throughout the central business district. Model refinements made on the basis of the data from this experimental program include the addition of a street-canyon submodel to compensate for the important aerodynamic effects of buildings on CO concentrations at streetside receptors. The magnitude of these effects was underscored by the concentrations measured on opposite sides of the street in San Jose, which frequently differed by a factor of two or more. Evaluation of the revised model has shown that calculated and observed concentration frequency distributions for street-canyon sites are in good agreement. Hour-average predictions are well correlated with observations (correlation coefficient of about 0.6 to 0.7), and about 80 percent of the calculated values are within 3 ppm of the observed hour-average concentrations, which ranged as high as 16 ppm.