ALBERT

Notes: Abstract Rhodococcus ruber NCIMB 40126 synthesizes copolyesters (polyhydroxyalkanoates) of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV), containing primarily 3HV monomer units, from a variety of single, chemically unrelated substrates. The 3HV content of the polymer is dependent on the choice of substrate and succinic acid yields high values, e.g., 92–95 mol%. The 13C-NMR spectrum of copolymer produced from [2,3-13C]succinate displayed similar enrichment of signals representing C-1, C-2, C-4 and C-5 of the 3HV component, whereas the C-3 signal showed negligible enrichment. Label from [1,4-13C]succinate was incorporated into the C-3 position of the 3HV monomer unit. The key enzymes of polyhydroxybutyrate (PHB) synthesis (3-ketothiolase, acetoacetyl-CoA reductase and PHB synthase) are present, have been studied and their specificities shown to permit the synthesis of poly(3HB-co-3HV). Attempts to detect putative enzymes of succinate metabolism leading to propionyl-CoA formation have so far proved incoclusive. The organism can readily utilise as nitrogen source the amino acids valine and isoleucine, which yield propionyl-CoA in their metabolism. Under sulphate-limited conditions the copolymer accumulated from valine possesses an enhanced 3HV content relative to glucose as substrate. The weight-average molecula mass (Mr) of PHB accumulated by Methylobacterium extorquens can be considerably higher (1.7 × 106) than previously reported and is dependent on the choice of carbon source, methanol yielding lower values (up to 6 × 105) than succinate (up to 1.7 × 106). The Mr of the PHB accumulated by both Alcaligenes eutrophus and M. extorquens is affected significantly by the concentration of the carbon source supplied, having lower values and higher polydispersities at higher substrate concentrations. During batch fermentation the Mr of PHB in A. eutrophus decreases gradually with time whereas the converse is true for M. extorquens.

Notes: This paper focuses on two factors that influence the acceptability of the expected value criterion as a method of handling risk or uncertainty in decision-making where damages from unusual physical occurrences such as hurricanes or floods must be considered. These are the length of time of project existence and the problem of obtaining accurate estimates of the probability of occurrence for different sizes of natural disasters. The problem of estimating accurate probabilities of occurrence for different sizes of natural disasters is not as great as it might appear and in most situations will not defeat the usefulness of the method. The time span during which the project is expected to exist has greater implications for the usefulness of the expected value approach appears highly applicable. However, it becomes less applicable for projects that are short-term in nature. The basis for distinguishing between short- and long-term projects is presented.

Notes: Fifty-two British and 29 Greek idiopathic membranous nephropathy (IMN) patients were analysed for DRB, DQA1, DQB1 and DPB1 gene polymorphism using second exon amplification and sequence-specific oligonucleotides (SSO). In addition 100 British and 92 Greek controls were analysed.A highly significant increased frequency of the DRB 1*0301 allele was found in IMN patients from Britain (80%), when compared to controls (27%, OR 10.6, P= 0.000004). A lower frequency of DRB 1 *0301 was observed in Greek IMN patients (33%), but this was just significant before correction, when compared to Greek controls (15%, OR 3, P= 0.02). The DRB3 allele most often associated with DRB 1 *0301 was DRB3*0101 (OR 4.2, P= 0.00025) in British patients and DRB3*0201/2 (OR 11, P=0.006) in Greek patients. In Greek IMN patients a decrease in DR16 was found (OR 0.08, P=0.004), and the overall incidence of DR2 was significantly lowered when both sets of IMN patients were combined (OR 0.21, χ2 17.6, P= 0.00013).The incidence of DQA1 *0501 was raised in both Greek (96%vs. 66%, OR 9.7, χ2 6.9, P= 0.009) and British IMN (85%vs. 45%, OR 7.4, χ2 20, P= 0.00007) patients. This gives some support to a proposal for a major role for this allele in IMN. However, DQB1 *0201 was also raised in both Greek (50%vs. 21%, OR 3.6, χ2 8.1, P= 0.005) and British (90%vs. 44%, OR 10, χ2 21.7, P=0.00004) IMN patients. The DQA1*0102 allele was significantly lowered in Greek IMN patients (15%vs. 32%, OR 0.05, 12.2, P=0.0008), probably reflecting a lowering in the DR16 haplotype. No significant difference was observed in the frequencies of DPB alleles in patients and controls.It is concluded that DRB 1*0301 has the strongest association with British Caucasoid IMN. The Greek Caucasoid IMN association with DRB 1*0301 is weaker, and a role for other alleles has not been eliminated.

Notes: The way the Water Resources Council proposes to measure the beneficial effects of national economic development and recreation is questioned and alternatives suggested. In measuring the former, the assumptions specified by the Council are questioned because they do not hold true in the market place. In addition, the Council's method of simulating a price per recreation day implies that an arbitrary price be selected from a range and multiplied times the number of days at no charge for use of the facilities. It is contended that these procedures would over state the economic benefits which in the real market would be measured by the selected price times the quantity demanded at that price.

Notes: The aim of this study was to locate all ferruginous discharges within the Welsh coalfield areas and to assess their impact upon receiving watercourses. The project was undertaken in two stages. In the first stage, visual assessments were carried out on an area of river bed affected by iron hydroxide deposition. Chemical samples of the discharges and the receiving watercourse were analysed for a suite of physico-chemical determinands. Ninety discharges were located impacting upon 59.4 km of river, and an area of 22 ha was affected by iron hydroxide deposits.A ranking method, incorporating the physical/chemical determinands, was developed to assess the comparative impact which discharges were having on receiving watercourses. A total of 33 of the top ranked discharges- (20 to classified watercourses and 13 to unclassified watercourses) having the highest environmental impact were selected; chemical, biological and fisheries impact assessments were then carried out on these discharges in the second stage of the project. The sites were then ranked on the basis of biological and fisheries impact. A list of the highest impacted sites was produced, and some of these were further investigated for remediation options and associated costs.

Notes: : The 26-mile man-made beach bordering part of Mississippi's Gulf Coast and the contiguous Mississippi Sound waters provide an important recreational and tourist attraction for that area. Being the tourist nucleus for the State, announcements in September 1973 by the Mississippi Air and Water Pollution Control Commission and the State Board of Health that Sound waters had reached a level of pollution that made them potentially dangerous for body contact was met with a myriad of responses. The resulting multi-governmental, multi-agency interface that resulted in trying to deal with the situation highlighted the type of problems that can arise when social, economic, political, and legal forces come to bear on a sensitive area. Questions of jurisdictional and legal authority to act, tourist industry economic pressures, and water quality testing and monitoring procedures were representative of the type of problems that arose during this period. A retrospective analysis of this problem served to isolate the type of articulation that is essential between federal, state, and local agencies vested with responsibilities such as monitoring water quality, protecting public health, etc. This paper develops some of the interface complexities that emerged in dealing with this problem and makes selected recommendations for other areas that may potentially face similar situations.

Notes: Abstract. An interview survey of farmers' assessment of the overall capacity of land, as well as its suitability for specific uses is compared with the judgement of the Soil Survey of England and Wales. The results are interpreted as showing that in a general evaluation the farmers are accurately aware of the quality of their land, but they are less well informed as to its true suitability for specific uses. The comparison shows the potential importance of land suitability analysis to the farmers, especially at a time of changing economic pressures.

Notes: 〈list xml:id="l1" style="custom"〉1The vertical distribution of the benthic fauna of the Speed River, Ontario, was studied over a 13-month period from October 1970 to October 1971. Various physical and chemical parameters of this interstitial environment were also measured.2Several new techniques for sampling the interstitial environment of rivers wert devised. These methods and their relative efficiencies are considered.3The validity of the terms ‘hyporheal’ and ‘hyporheic’ are discussed and the term ‘hyporheos’ is offered to replace the former.4A brief resume of interstitial sampling methods is given with comments on their limitations for sampling deep heterogeneous substrates.5Chemical parameters are thought to be more important in the control and distribution ofthe fauna than physical parameters.6It is suggested that many larvae of stream-dwelling chironomids have over-wintering stages when they penetrate deep into the substrate to: (a) actively feed on the trapped organic detritus; (b) follow an optimum temperature for development.7It is suggested that the shape of an organism determines its success as a hypo-rheic form and examples are given.8The numbers of animals oecurring in the sub-benthic populations are shown to be very large indeed. For the Speed River, estimates of between 184,760 and 797,960 animals/m^ are made for different times of the year. Dry weight biomass is estimated o t vary between 30 9 g and 253-2 g/m^ throughout the year.9Sub-benthic or hyporheic populations are shown to exist in at least three other Canadian rivers. Some ofthe animals found are shown to be common to two or more of these rivers.10The inefficiencies of many conventional benthic samplers in sampling the total biomass of certain streams with hyporheic populations is discussed.

Notes: 1. The life history of the small herbivorous stonefly Nemoura trispinosa Claassen was studied in a variety of small springs in southern Ontario, Canada. Nymphs generally were able to tolerate a wide range of environmental conditions and were found in 78% of habitats sampled, although population densities differed markedly.2. Life-cycle patterns varied from a univoltine, slow seasonal type to a univoltine, fast seasonal type with extended egg development. In one, highly stable, spring the life cycle was semivoltine. Inter-year variation was studied for 5 years in one spring and was found to be low relative to among-spring variation.3. Differences in the life history traits of N. trispinosa populations from our spring series were most probably an expression of phenotypic plasticity rather than of genetic differentiation.4. Maximum annual water temperature was the factor most influential on nymphal growth rate (non-linear relationship), whereas range in generation time was related to the degree of habitat permanence.

Notes: SUMMARY. 1. Reactions of individual predatory stoneflies to contact by individual mayfly prey, and vice versa, were studied in the laboratory using two sets of species, one from a stream in southern Ontario. Canada, and the other from a stream in North Wales.2. Based largely on information received via their antennae, the stoneflies were capable of distinguishing between conspecifics and mayfly prey and between prey species. A clear preference for certain prey species was evident but less preferred species were made more attractive when damaged or when the stoneflies were very hungry. Detection of conspecifics by stoneflies was confused in the presence of prey or the local smell of prey body fluids and this led to interference during hunting and feeding at high predator densities.3. Some mayfly species were capable of distinguishing between conspecifics. other mayflies and predators. The cerci were important in intra- and interspecific contact encounters between mayflies and were used in a fencing fashion to establish a minimum distance between nymphs. However, the cerci did not appear to play an anti-predation role as stoneflies captured and ate mayflies with and without cerci in equal numbers.4. Reactions to conspecifics by the Palaearetie mayflies Rhithrogena semicolorata (Curt.) and Baetis rhodani (Pictet) were similar to those of the ecologically-equivalent Nearctic species Stenonema vicarium (Walker) and Baetis vagans McDunnough.5. In encounters between mayflies, intra- and interspecific responses were similar. However, the responses of some mayfly species to conspeeifics were modified in the physical presence of a predator or the water from its holding tank. Different mayfly species made specific responses to predaeeous stoneflies. Responses to a herbivorous stonefly were either similar to conspeeific encounters or were intermediate between them and encounters with predators.6. Experiments to reveal the exact nature of the stonefly stimulus detected by the mayfly nymphs strongly suggested that there were two components to the stimulus. One was physical contact by the predator's antennae, the other was chemical in nature and could be detected only over short distances (up to a few mm). Independently each could elicit a response, but combined their effect appeared to be synergistic.7. Different mayfly species responded differently to the stonefly Phasganophora capitata (Pictet) and this sequence of sensitivity was mirrored by the predator's choice of prey species—the most sensitive to the predator being the favoured prey and the less sensitive the least favoured. The significance of these findings to optimal foraging theory, as applied to tactile predators, is discussed.