ALBERT

Notes: In a few homoiothermic host species, Eimeria spp. in a schizogonic stage, a gamogonic stage, or as resting sporozoites infect nonepithelial tissues. However, epithelium serves as a critical site in the cycle of these and all other species known from warm-blooded hosts. Eimeria funduli, infecting at least four different killifishes, undergoes both schizogony and gamogony in non-epithelial hepatic and pancreatic cells and requires an invertebrate host to complete its cycle. Oocysts are not released from the living fish into the environment. The cycle for this species, or aspects of it, may exemplify those found in several piscine species infecting nonepithelial (and possibly epithelial) cells. Eimeriu funduli differs from most species of Eimeria infecting homoiotherms in other respects, some of which may also characterize traits for piscine and other poikilotherm eimerians in general. Endogenous development is affected by temperature and host-age, sporogony occurs in the host, and infections occur in several related fishes. The presence of an intermediate host in at least E. funduli and the presence of sporozoites in macrophages of several eimerians of homoiotherms, as well as other features, suggest a closer relationship between eimeriids and Lankesterella, Schellackia, and even the Haemosporina than previously assumed.

Notes: An assessment is given of the present state of the art in chemotherapy of protozoal infections with suggestions as to improved results in the future, especially by rendering available drugs more effective. Selective targeting of chemotherapeutic agents through enhancement of lysosomotropic character has been demonstrated, particularly through the use of liposome-encapsulated drugs.

Notes: Phytomonas davidi (Trypanosomatidae) possesses typical trypanosomatid organelles: subpellicular microtubules, kinetoplast-mitochondrial complex, K-DNA, and four subflagellar pocket microtubules. A greater concentration of subpellicular microtubules was observed in the latex forms than in those found in the salivary glands of its insect vector. Only in the latex flagellates (the stage with postnuclear torsion) were subpellicular microtubules interconnected by crossbridges observed. Morphology and development of mitochondrial aristae varied according to the source of the flagellates. Organisms taken from culture medium had extensively developed plate-like cristae; sparse tubular cristae were observed in the latex forms; and highly developed tubular cristae were seen in flagellates from the lumen of the vector's salivary glands, though organisms in the salivary gland channels had few or none.

Notes: In contrast with isosporoid species of coccidia that have established extraintestinal phases of development, the eimeriids, except for a few species, generally have been considered inhabitants of the intestinal tract. Eimeria infection in sandhill cranes (Grus canadensis) and whooping cranes (G. americana) may result in disseminated visceral coccidiosis. Nodules were observed in the oral cavity of 33% (n = 95) of the G. canadensis at the Patuxent Wildlife Research Center (PWRC) in Laurel, MD. Necropsy of six of the afflicted cranes revealed granulomatous nodules in many tissues and organs. Histologic studies disclosed protozoan organisms morphologically resembling schizonts in the granulomas, and endogenous stages of coccidia were present in the intestines of four birds. Fecalysis of three of four sandhill cranes yielded oocysts of E. reichenowi and E. gruis. Only E. reichenowi-type oocysts were recovered from a dead whooping crane sample. Domestic broiler chicks each intubated with about 1 times 106 pooled sporulated oocysts of E. reichenowi and E. gruis were not infected. Exposure of six incubator-hatched and hand-reared sandhill crane chicks to oocysts artificially (two chicks) and naturally (four chicks) resulted in typical infection of intestinal epithelium with invasion of subepithelial tissues extending to the muscular layer and widespread extraintestinal development. Asexual and sexual stages occurred primarily in macrophages in the liver, spleen, heart, and lung. In the lung, oocysts were found in bronchial exudate and epithelial lining cells. Six of ten G. canadensis chicks, one adult G. americana, and three of five G. americana chicks that died naturally at PWRC had disseminated visceral coccidiosis.

Notes: The somatic cortex of Spathidium spathula is described ultrastructurally. The pellicle consists of an outer membrane and an underlying alveolar system. Numerous membrane-bound mucocysts and spherical electron-opaque bodies have similar circular sites of attachment to the outer membrane. Below these are a microfibrillar zone and an underlying region of rough ER. Mitochondria are lined up under the rough ER in longitudinal cortical ridges. Parasomal sacs are found near the basal bodies and are associated with cytoplasmic membranous sacs. Various microtubular and fiber systems are associated with single basal bodies: (1) a short kinetodesmal fiber; (2) two transverse microtubular ribbons and a transverse fiber; (3) a postciliary microtubular ribbon, initially sandwiched by two fibers, which gives rise to longitudinal subpellicular microtubules extending posteriorly for a distance of some four or five basal bodies; and (4) a system of overlapping subkinetal microtubules. A three-dimensional reconstruction is included. The somatic cortex of S spathula is similar to that reported for other Haptorida of the ciliate subclass Gymnostomata.

Notes: The species-specific lethal factor obtained from Amoeba indica, a freeliving mononucleate amoeba, can be partially purified by differential centrifugation, gel exclusion chromatography, and elution from Cibacron blue-agarose. The factor is unstable in the partially purified form, but activity is correlated with a heat-labile protein having an apparent molecular weight of 186,000. The factor causes inhibition of division and death when injected into A. proteus. Purification of the lethal factor indicates that aggregation of the factor with amoebal proteins is not a hindrance to further investigation. The natural role of the factor is discussed.

Notes: Triplet conjugants of Paramecium multimicronucleatum, in each of which the third cell unites by its anterior and to a posterior part of one of the conjugating pair, are induced by conjugation inducing chemicals, KCl and acriflavine in a Ca11-poor condition. If the triplets are prematurely transferred to medium free of such chemicals, the third cells usually separate and no macronuclear fragmentation occurs in them. But in third cells of long lasting triplets, macromuclear fragmentation regularly begings at ∼12 In after chemical treatment Staluhzaton of cell union and determmation of macronuclear fragmentation occured between ∼100 and ∼130 min after initiation of chemical treatment. Electron-microscopic observation of the stabilized third cell revealed that the two cell membranes at the uniting region were partially fused to form cytoplasmic bridges. Chemically treated cells began to cases feeding before the cell union and fully ceased such activity at ∼130 min after the treatment.

Notes: In its amoeboid stage, Protacanthamoeba caledonica n. g., n. sp. closely resembles the genus Acanthamoeba, on both light- and electron-microscopical levels, including possession of a centrosphere with a plaque-shaped centriole-like body. The cyst wall differs from that of Acanthamoeba in lack of preformed exit pores and in fine structure; the occasional apparent division into exocyst and endocyst is due to irregular splitting. The strain isolated from a Scottish estuary did not grow at 37°C and did not grow normally on agar made with 25% sea water, but cysts remained viable after a week in full-strength sea water. Protacanthamoeba n. g. is distinguished from Acanthamoeba on the basis of cyst structure, but it is assigned to the family Acanthamoebidae.

Notes: Blastocrithidia triatomae, a species very resistant to cultivation in conventional media, was successfully grown in association with cultured lepidopteran cells. The cultured flagellates were identical to those in the insect host, including the presence of characteristic cysts on the flagellum. Growth rate was better for cultures in the Heliothis zea medium than in IPL-45 medium or modified McConnell's medium.

Notes: Leptomonas lactosovorans n. sp. is described from the gut of the reduviid hemipteran Zelurus martinsi. It can be grown in a defined medium. The requirements for amino acids, vitamins, purine, and heme were similar to those established for Crithida fasciculata. Growth is stimulated by aeration. Generation time is longer than for any other insect trypanosomatid described; its utilization of lactose as a carbon source is a unique feature among trypanosomatids.

Notes: Anti-malarial gamete antibodies prevent the fertilization of gametes in the mosquito midgut and prevent transmission of malaria. Recently, hybridoma cell lines secreting monoclonal antibodies (10G3 and 11C7) against gametes of the malarial parasite have been developed. These antibodies act synergistically to mediate 80–90% suppression of the infectivity of gametocytes, although neither monoclonal antibody alone has a significant effect on gametocyte infectivity. We performed immuno-electron microscopy to characterize the interactions of these monoclonal antibodies with gametes of Plasmodium gallinaceum. Male gametes exposed to either 10G3 or 11C7 agglutinated into loose clusters, while those exposed to a mixture of 10G3 and 11C7 agglutinated into long, rope-like bundles. This difference appears to be related to the distribution of the antibodies on the surface of the gametes. When 10G3 or 11C7 labeled with a ferritin-conjugated anti-mouse Ig were used singly, the ferritin particles were distributed in focal areas over the surface of the parasites. By contrast, when the male gametes were exposed to a mixture of 10G3 and 11C7, the ferritin particles were distributed over their entire surface. Female gametes reacted similarly to these antibodies. These observations indicate that combinations of antibody specificities that reduce fertilization efficiency coat the entire surface of the gametes. On the other hand, focal interactions resulting from a single antibody are unable to block fertilization.

Notes: Inhibition of cell division in Euglena gracilis by visible light is pH-dependent, being most severe in the pH range 3.5–5.0. Transfer of phototrophic cells from pH 6.8 to pH 4.2 can lead to cell death at modest light intensities (500 ft-cd) and inhibition of division at lower intensities (300 ft-cd). Inhibition is preceded by a large influx of phosphate, most of which remains in the cold PCA pool. It is suggested that light may act to reduce control over phosphate entry at these intermediate pH levels, and excess phosphate leads to inhibition of cell division or death.

Notes: Le mode de contamination par Aggregata a étéétudié expérimentalement in vivo chez le Crabe, in vitro sur cultures cellulaires de Mollusques, puis suivi en microscopie électronique. Quelques heures après le repas infestant, les spores s'ouvrent dans l'estomac du Crabe et les sporozoïtes gagnent l'intestin moyen. Là ils traversent l'épithélium dans les espaces intercellulaires. La perforation de l'epaisse basale est liée à l'apparition d'une substance dense, de nature probablement enzymatique. Les lésions causées aux tissus du Crabe sont minimes. Les mérozoïtes sont capables de pénétrer en culture dans des cellules provenant de divers Mollusques; la membrane de la cellule-hǒte n'est pas rompue. Un debut de développement est observé avec l'apparition d'un nucléole dans le noyau.

Notes: A virulent strain of Babesia bovis (“L” strain) was rendered avirulent by irradiation with 35 krads with a γ source. Another virulent strain of B. bovis (“C” strain) was made avirulent by rapid blood passage through 12 splenectomised calves. Both the parent virulent and their respective avirulent strains were injected into susceptible cattle. A nonfatal disease was observed in those intact cattle that had avirulent parasites; however, a fatal disease was produced in those animals that had received virulent parasites and in splenectomised calves that had received avirulent parasites. Blood kinin levels rose and plasma kininogen levels fell significantly in those animals infected with both virulent strains. Nonsignificant changes occurred with these parameters in animals infected with avirulent parasites. Preparations of disrupted parasites were obtained from the four parasite populations. Both virulent strains contained high levels of protease. The avirulent forms contained insignificant amounts. As parasite doubling times and maximum parasitaemias were the same for all four parasite populations, we conclude that these enzymes are not obligatory for parasite multiplication in the vertebrate host. Their role in producing pathological changes in the host is discussed.

Notes: The United Nations' newly completed study of purchasing power parities covering 34 countries varied in region, income level, and form of economic organization shows the systematic differences between the usual view of the structure of the world economy arising out of international comparisons based upon foreign exchange rate conversions and the structure one sees when actual prices are available.The real per capita GDP of developing countries is understated relative to developed countries when exchange rates are used in converting countries' national income accounts to a common currency, with the degree of understatement for any two countries being inversely related to the per capita income difference between them. The reason for this is that relative prices in the non-traded goods sector are lower relative to traded goods prices in low income countries. The systematic pattern observed in the 1975 data of the 34 countries has been extrapolated over time and space to get estimates of GDP for other years and countries.In the absence of detailed price data, the real shares of final expenditures devoted to particular components of the total can only be estimated as the proportion of own currency total expenditure devoted to the components. The observed differences in the pattern of prices of poor countries relative to rich for different components makes this clearly wrong for international comparisons, and in systematic ways. For example, (i) the relative price of services compared with commodities in poor countries is lower than in rich; so the apparent tendency of the share of services to rise as a country's income rises disappears when real quantities are considered; similarly, (ii) the relative price of capital goods is greater in poor countries compared with rich ones, so the difference in investment ratios out of GDP between rich and poor countries is understated.

Notes: The change in goods and services available in a national economy brought about by the shifting of external price relationships is referred to as the terms of trade effects. This paper reviews the various methods which have been devised since the war to define and quantify such effects on the Gross National Product. The statistical annex shows that, as far as OECD countries are concerned, the differences between the various measures are not significant. Whereas the effects from terms of trade represented, on average, less than one half of one percent of the GNP of OECD countries during the 1960's the percentage has increased substantially since 1973, due most importantly to the increase in the oil price; by 1977 (on a 1970 price basis), it had reached 5 percent of GNP in Japan and up to 6 percent in Italy. On the other hand, the extreme case of Saudi Arabia where various formulas generate effects amounting to between one half and the whole of GNP, indicates that the measurement of terms of trade effects by various methods may give different results.

Notes: The concern with income distribution has always mainly existed because of a concern with individuals' economic welfare. In recent years, the question has arisen whether the distribution of annual income—the distribution most often studied—is the best proxy for the distribution of economic welfare. Other measures, such as lifetime income, have been proposed instead.The paper starts with a discussion of how to define and measure the distribution of lifetime income. By using a simulation model, which partly consists of estimated functions and partly of tax functions taken directly from tax laws, distributions of lifetime income, variously defined, are then constructed. These distributions are compared with each other, and with distributions of annual income. The simulations indicate that the distribution of lifetime income is considerably less unequal than the distribution of annual income. Whether inheritances are included or not seems to be of no importance for the inequality of lifetime income. If, on the other hand, we include the value of leisure time in lifetime income, inequality increases by about 10–15 percent. Distributions of income after tax have Gini coefficients which are approximately 25 percent less than the Ginis for the before-tax distributions. We thus find that the picture of inequality we get is very much dependent on which income concept we use.

Notes: This paper discusses the history of the French development of satellite accounts during the late 1960s and 1970s, noting the circumstances that led to the initiation of work in this area and describing the types of problem encountered. It then goes on to draw, on the basis of the French experiment, more general conclusions and to present a proposed accounting framework. The final section considers the concept of social expenditure, but concludes that, at least for the present, it is not possible to construct a useful global concept.

Notes: The economy of Liberia is one in which, in spite of past satisfactory growth performance, a high level of income inequality persists. In 1977, for instance, a mere 2 percent of the people accounted for some 33 percent of nation-wide wage income. These people live disproportionately in Montserrado County in which the capital city is located. While each of the other counties are largely rural and poor, each has far lower intra-county inequality than wealthy Montserrado.Intersectoral location of the income-earner, average income levels and the extent of access to human capital formation opportunities are some characteristics of the economy that have been found to explain significant portions of intercounty variations in the levels of household income concentration. Income inequality is reduced with increases in the extent of agricultural activity as the share of the top income group falls and that of the bottom group rises. The reverse happens with growing urban-area activity. Higher income concentration occurs with rising per capita incomes as the top group's income share rises and the bottom income group's share falls. While this appears to be an instance of the Kuznet U-shaped hypothesis, here there are no definite signs of a possible reversal any time soon. The levels of access to educational facilities move inversely with the level of inequality, with expanding elementary facilities benefiting the poorer people at the expense of the wealthy while the reverse happens in the case of expanding secondary educational facilities.

Notes: This article describes what happens to income distribution during intensive changes in gross domestic product due to external market conditions. It deals specifically with an open market petroleum-based economy, Trinidad and Tobago, and reviews changes in national product and income levels and the income distribution pattern over the twenty year period 1957–76.The paper argues that during the period characterized by subperiods of steady growth and rapid growth in GDP (the latter associated with the petroleum price rise), income inequality increased between 1957 and 1972 and then decreased in the post petroleum-price-rise period of rapid growth 1973–76. While the effect of intensive changes in national product did trickle down to the lower income groups, income inequality in 1975–76 was greater than that existing in 1957–58. An examination of the spatial, occupational and temporal aspect of the distribution pattern points towards the elimination of structural dualism in the economy as the surest path towards greater income equality in Trinidad and Tobago.

Notes: The debate on how to deal with changes of relative prices in national accounts has, so far, remained inconclusive, especially with regard to the question of how to measure gains from changes of terms of trade. Keeping the experiences of the 1970s in mind (i.e. substantial changes of relative prices sparked off by increased oil prices), this state of affairs is not considered tenable.On this background, the paper takes up the old debate on how to deflate figures of domestic product, total as well as by industries. It tries to argue that deflated figures should be presented not only as real product figures by industries (using the double deflation method), but also as real income figures, obtained by deflating the current-prices figures of a certain year by the same general price index. When this is done according to procedures spelled out in detail, gains/losses from changes of the terms of trade in foreign trade will show up as an integral part of the framework.In the paper, special attention is given to the concept of industry terms of trade. On the basis of simplifying assumptions (which are, however, relaxed in the final part of the paper), it is shown how the ratio of real income divided by real product of a certain industry will be proportionate to the terms of trade of the industry concerned, when the latter concept is defined in the appropriate way. Furthermore, the sum of the industry gains/losses from changes of their terms of trade will be equal to the gain/loss of the economy taken as a whole from changes of the terms of trade in foreign trade.

Notes: In this paper, I investigate the validity of the Modigliani-Brumberg (M-B) model as an explanation of the variation of wealth holdings among households. The model as such, even with the inclusion of estimates of household lifetime earnings, explains only a minute portion of the variation in household wealth. Indeed, for certain groups such as non-white, rural residents, and the low educated, the coefficients of the regression model are insignificant. Moreover, when the top wealth holders are removed from the sample and when non-cash financial and business assets are eliminated from the household portfolios, the explanatory power of the M-B model increases markedly. Essentially, the validity of life-cycle wealth accumulation models must be restricted to the white, urban, educated middle classes and their accumulation of housing, durables, and cash. The rich have very different motives for saving and very different sources of saving, while the poor do not earn sufficient income over their lifetime to accumulate any non-negligible wealth.

Notes: This paper presents an analysis of the distributive impact of government expenditures in the United States. The analysis uses a household-level microdata file drawn from the 1970 U.S. Census of Population, with additional income and tax variables drawn from the Internal Revenue Service 1969—70 Tax File.The results are presented at both federal and local levels and include analyses of the distribution of individual benefits, as well as of overall taxes and net benefits. Since a microdata file was used, distributional effects are examined with respect not only to the “traditional” variables of income class and household size, but also with regard to the number of earners in the household and the sex and race of the household head.In a further paper in a subsequent issue of this review we will present the results of a similar analysis for the United Kingdom, and compare the results for the two countries.

Notes: In an important recent book dealing with the measurement of income inequality with particular reference to poverty,1 Prof. N. Kakwani derives several poverty indices, investigates the effect of negative income tax schemes with the help of those indices and gives a numerical illustration based on Malaysian data.The aim of this note is to point out some logical flaws in his argument. Some of the ideas expressed in the part of his book we are concerned with have been disseminated for some time now2 and referred to in subsequent literature;3 yet their shortcomings do not seem to have attracted anyone's attention. The introductory section gives a concise presentation of the relevant part of Kakwani's contribution. The next two sections deal with some problems with his approach.

Notes: The conceptual framework of the system specifies that societal resources are limited by two basic factors: the amount of available human time, and the stock of wealth inherited from the past. Wealth is defined very broadly to cover not only the conventional tangible capital assets familiar to economists, but also intangible human and other capital assets, stocks of organizational capital reflected by networks of social support systems (the family, the neighbourhood), stocks of environmental assets (the sun and air), and stocks of socio-political assets (security, freedom of choice). Human time covers market work, household production, leisure, and biological maintenance.Human time and capital stocks are used within households to produce a variety of tangible and intangible outputs, and these outputs in turn are used to produce a variety of satisfactions (utilities) or to augment stocks of capital, or both.The basic sources of well-being in the system are ultimately of two types: well-being is produced as a consequence of the intrinsic benefits from all activities engaged in by individuals, which is to say that people have preferences over the way they spend their time; secondly, people derive utilities from the existence of various stocks or states of society, and these satisfactions are independent of the way in which time is used. The satisfactions associated with flows of goods are subsumed by satisfactions derived from activities associated with those goods.The system contains a set of linkages among the various parts:inputs of goods and time are used to produce tangible household output, using the familiar notions of household production functions and constrained optimization; tangible household products, which are intermediate in the system, are used in conjunction with human time to produce direct satisfactions or to augment household capital stocks; both household (micro) and societal (macro) capital stocks are linked directly to psychological well-being; household activities are linked directly to flows of satisfactions, termed process benefits in the system; household preferences and values relating to policy variables are linked to public policies of various sorts, and policies modify the constraints and opportunities relevant for household decisions.The system also has dynamic linkages. Modifications of household or public stocks produce impacts on future flows of well-being; satisfactions from activities may adapt to the existence of constraints, hence changes in constraints can modify preferences and subsequently modify activities; and household behavior has a life-cycle dimension which is inherently dynamic.

Notes: In the United States, the life-cycle relationship between initial Social Security contributions and subsequent benefits causes the effect of Social Security on income distribution to be overestimated in a single-period analytical framework. By separating the annuity from the redistributive aspects of Social Security we provide a life-cycle framework for measuring its net effect on redistribution. To this point in its history, we find all income classes have received positive net life-cycle income transfers and, in an absolute sense, upper-income groups have done at least as well as lower-income groups. This suggests a reason for the near-universal support of Social Security by past generations, as well as the controversy which now surrounds it. As it becomes apparent to younger cohorts of taxpayers that many of them will be net losers, it is inevitable that Social Security will be subject to the same controversy as other welfare programs which attempt to redistribute income.

Notes: Using data from the 1973 National Survey of Family Growth, the present study analyzes, for blacks and whites separately, the impact of female market activity on the inequality of the income distribution among households. The family life cycle is divided into three stages, according to the presence and age of children: (1) the interval between marriage and the birth of the first child, (2) the child-rearing interval, and (3) a final period which begins when all the children have reached school age. Using the coefficient of variation as an indicator of inequality, the empirical results show that in period 1, the contribution of white working wives has a large equalizing impact, while that of their black counterparts results in a slight increase in dispersion. In the child-rearing and post child-rearing stages, the labor supply of mothers decreases family income inequality by a small amount for both black and white households. A decomposition of the squared coefficient of variation of family income is presented to aid in the interpretation of these findings.

Notes: Although national and sector balance sheets have long been regarded as part of the national accounting framework, for a variety of reasons their compilation by official statisticians has been the exception rather than the rule. A programme of balance sheet work in the United Kingdom Central Statistical Office has recently been completed and the results published. The theoretical and practical problems arising in the course of this work are described and discussed. Summary results are given together with an interpretation of the main changes in the sectoral composition of national wealth between 1957 and 1975.

Notes: This paper presents an analysis of the distributive impact of public expenditures and taxes in the United Kingdom. The analysis uses household level microdata from the 1971 Family Expenditure Survey, with tax and expenditure aggregates drawn from the national accounts.The analysis is the first to allocate all taxes and public expenditures for the United Kingdom, and the results are compared to those from the more restricted analyses carried out by the U.K. Central Statistical Office. Results are presented for individual taxes and benefits as well as for overall net benefits and they describe distributional effects with respect to income class, household size, number of earners and housing tenure.A final section of the paper compares the results to those from a similar analysis for the United States which were reported in the previous issue of this review.

Notes: This paper considers the impact upon measures of corporate income of a number of concepts of the maintenance of the existing capital of an incorporated trading enterprise. A main distinction is drawn between the maintenance of all the assets employed in trading and the maintenance of the net assets attributable to the owners. Measures of income and of rates of return to capital depend on whether all the assets, or only the net assets attributable to the owners, are being considered. There are three sections of the paper after an introduction. Section 2 is conceptual and section 3 illustrates the concepts, with figures for U.K. manufacturing industry in 1975 to 1977, in which the figures in company balance sheets are adjusted from book values to estimated replacement cost, and estimates are made of depreciation at replacement cost and of the consumption of stock (inventories) at replacement cost. These figures follow the concept of maintaining physical assests. I have added calculations which extend the concept of capital maintenance to all operating or trading assets, including monetary working capital; and which then calculate the amounts necessary to maintain the assets attributable to the owners of a business. The three main methods are: to apply a gearing adjustment to abate the additional capital maintenance provisions for operating assets (which are realized revaluations by reference to their original cost); to take into income additionally the geared (or debt financed) portion of unrealized revaluations; and-what is conceptually much the same thing-to count as the charge for debt only real interest (which may be negative) rather than nominal interest. Section 4 considers some problems of aggregation, particularly the derivation of aggregates for the sectors of the economy, when based on figures for individual enterprises using the various approaches to capital maintenance.

Notes: Expanded measures of government output include imputed values of the services of government capital, uncompensated factor services of military draftees and jurors, and net revaluations, as well as the usually included compensation of employees. The government output is allocated to consumption, capital formation and product intermediate to other sectors, on the basis of its classification in ten broad functions: defense, space research, education, health, sanitation, transportation, parks and recreation, natural resources, welfare, and general administration. Final government product in 1976, including $116 billion in defense and $125 billion in education, amounted to $450.5 billion, which was 26.5 percent of the 1976 GNP. This final government product corresponded to the BEA measure of $191.6 billion.Total capital formation related to government is defined to include both government product which enters into capital formation in other sectors and government expenditures for its own capital accumulation. After a more rapid rate of growth in previous years, this total government capital formation in the United States in 1976 is found to exceed gross private domestic investment. A significant but only minor portion was found to be constituted by government expenditures for capital goods and change in government inventories. Investment in research and development, health and, particularly, education and training, were dominant components in capital formation related to government.

Notes: This paper focuses on the use of statistical matching in the estimation and analysis of the size distribution of family unit personal income. The paper begins with a brief discussion of data on the size distribution of income in the U.S. and their limitations. Several methods of improving or augmenting those data are described, and earlier examples of statistical matching for that purpose are mentioned. A brief summary of the types of statistical matching methods which have been used is also presented. Then a recent example of statistical matching carried out at the Office of Research and Statistics, Social Security Administration, is described, and the effects on the size distribution of adjusting and augmenting the initial data using the statistically matched data from that example are shown. Material relating to the accuracy of that statistical match is presented in the appendix.

Notes: This article presents the results of the first French efforts to assemble information on the assets and liabilities of the different economic agents. The estimates cover the five-year period 1972–76, with complete balance sheets for the end of 1971, 1972, and 1976. The experimental efforts showed that estimation was feasible. It was possible to bring together the varied, often dispersed, and rarely consistent existing information into an integrated body of aggregates adapted to macroeconomic analysis. The report stresses the importance of articulating the wealth accounts logically with the flow accounts, into a complete, closed, and consistent whole in which the theoretical objectives are well specified. It also points out the limitations of the approach, stemming primarily from the state of the basic statistics relating to wealth.

Notes: This paper is concerned with the distribution of wealth in Sweden in 1975 and its development during the period 1920–75. The paper is based on a large study on wealth undertaken for the Swedish Commission on Wage-Earners and Capital Formation. The first report from this study was presented in 1979 as a book in Swedish: Roland Spånt, Den svenska förmögenhetsfördelningens utveckling (The Development of the Distribution of Wealth in Sweden), SOU 1979:9. That first report will also be published in English. Prior to that the main results can be found in this paper.During 1980–81 we intend to publish specific reports on the distribution of shareholding, the effects of inflation, the development of the distribution of wealth 1975–78, the importance of pension rights etc.

Notes: Present national accounting conventions regarding the treatment of flows and stocks in the petroleum sector are considered to be unsatisfactory. But changes in reporting requirements for oil and gas producers open up possibilities for a more satisfactory treatment.In this article some aspects of the newly adopted requirements are presented and the possible uses of the additional information available for improving social accounts are discussed.

Notes: Book reviewed in this article:Cedric Sandford et al, Costs and Benefits of VAT

Notes: Dipole-dipole induced polarization (IP) data are displayed typically as multi-level profiles, or as contours on vertical sectional plots referred to as pseudo-sections. The dipole-dipole array tends to yield IP anomalies in which the most anomalous values are displaced laterally from the source body. The data patterns are fairly interpretable on pseudo-sections or on multi-level profiles but are sufficiently complex to discourage the contouring of the data in plan.A method was developed for the presentation of dipole-dipole IP data on a contour map. The method consists of a simple averaging of data which can be performed manually if desired. It yields a single output value per station which reflects all levels of the pseudo-section, and is suitable for contouring in plan. The advantage of the technique is that it provides a quantitative picture of IP anomalies in their background or regional setting.

Notes: Constant offset sections can be mapped to a fixed offset and compared in order to provide a method of velocity analysis. The direct mapping to zero offset prior to stack might provide an alternative processing procedure to NMO and stack. The main advantage of such a procedure would lie in the correct treatment of cross-dips, but interpretational advantages might also follow from the performance of partial stacks biased to either high or low offset information.

Notes: Induced polarization and resistivity model studies over thin dykes for varying resistivity contrasts, depth of burial, and dip angles show striking parallelism of the surface apparent resistivity contours with the boundary of the body. This effect may be utilized for the estimation of strike length of the body. Results show that intermediate values of the electrode spacing is satisfactory for detection under widely varying conditions of resistivity contrast and depth. The percentage frequency effect (P.F.E.) and the metal factor (M.F.) responses are found to be more sensitive to the variation in the depth of burial than the resistivity responses. Pseudosections for P.F.E. and M.F. are concentrated much closer to the body than the resistivity pseudo-sections.

Notes: A direct interpretation scheme is developed which is capable of determining most of the geological features of a ground which can be assumed to be two dimensional in structure. This scheme extends the earlier work of Pekeris (1940) and Koefoed (1968) to the case where the basal layer of a ground is undulating. It also has a limited use for finding the parameters of a dipping dyke in the lower medium. Though the top and dip of the dyke can be determined, this is not true for the thickness.

Notes: Laboratory studies of absorption-frequency behavior in rocks often use spectral ratios of digitally recorded ultrasonic signals which have been transmitted through a rock sample and a reference sample of very low absorption, respectively. It is proposed to treat the digitally recorded signals as an autoregressive-moving average (ARMA) process which, using recursive filter concepts, can be represented as a ratio of two polynomials in the z-transform variable z. The numerator polynomial contains only that part of the signal that is modified by anelastic effects, whereas the denominator contains the elastic effects of the physical apparatus such as reverberations. Examples are given which show that this separation of the recorded signal greatly facilitates the laboratory investigation of loss mechanisms and absorption-frequency behavior based on spectral ratios.

Notes: The generalized integral equation for the electric potential governed by a quasi-harmonic equation can be derived via a variational formulation. For surface current distributions it is not always a Fredholm integral equation of the second kind. Numerical solutions of the general heterogeneous problem can be obtained with the “reciprocal averaging technique”, where the solution is obtained a second time after exchange of source and field points.

Notes: A method to calculate the resistivity transform of Schlumberger VES curves has been developed. It consists in approximating the field apparent resistivity data by utilizing a linear combination of simple functions, which must satisfy the following requirements: (i) they must be suitable for fitting the resistivity data; (ii) once the fitting function has been obtained they allow the kernel to be determined in an analytic way.The fitting operation is carried out by the least mean squares method, which also accomplishes a useful smoothing of the field curve (and therefore a partial noise filtering). It gives the possibility of assigning different weights to the apparent resistivity values to be approximated according to their different reliability.For several examples (theoretical resistivity curves in order to estimate the precision of the method and with field data to verify the practicality) yield good results with short execution time independent of shape the apparent resistivity curve.

Notes: A method is given for solving the dc electric field problem of a point current source in an anisotropic 2 1/2-dimensional structural model. The surface integral equation of the field strength is given. Parallel to the strike the field strength is represented by a Fourier series. On the plane perpendicular to the strike each term of the field strength series is solved by means of the method of sub-sections, where linear behaviour of field strength over the sub-sections is assumed. Some numerical examples for different galvanic effects are given.

Notes: It is proposed that the vertical resolving power of a seismic signal is controlled by three aspects: the width of the central lobe, the side lobe ratio, and the side-tail oscillations. A comparative study of zero-phase signals covering the same frequency range shows that improvement of any one of these aspects inevitably leads to deterioration of one of the other aspects.An analytical simulation model is proposed of zero-phase signals free from side-tail oscillations, in which both the width of the central lobe and the side lobe ratio are adjustable. Analysis of the spectra of this model shows that, while the high frequency content of the spectrum is essential for obtaining a small width of the central lobe, the low frequency content of the spectrum plays an essential part in causing a low value of the side lobe ratio.

Notes: The objective of this study is to generate the separation-distance-domain (r-domain) transformation of the theoretically calculated wave number domain (m-domain) electromagnetic induction field component Bz(m, ω) of a stratified medium and to search for interpretive information which has been absent in the previously achieved numerical solutions of the problem.The r-domain kernel R̃(r, ω) function defining the induction field appears to adequately reflect the layering and electrical properties of the medium if it is expressed as a function of the frequency if the source-receiver separation r is small with respect to the thickness of the first layer. However, exact values of the conductivity cannot be distinguished from those of the neighboring values unless a resistive basement layer is present. This feature is the result of the truncation in series representation of the kernel function R̃(m, ω). However, this truncation is regarded as significant in the case of a conductive first layer. In m-domain static-zone studies, a conductive first layer slightly influences its r-domain correspondent.Although the computational cost of obtaining the kernel B(r, ω) by evaluation of the convolution in a cylindrical coordinate system is high, this semi-analytic solution is still superior to those based on the asymptotic assumptions.

Notes: A novel hybrid stubble turnip, Appin, bred by the Scottish Plant Breeding Station (Brassica campestris ssp. rapifera cv. Tigra ×B. campestris ssp. nipposinica cv. Mizuna) was compared in small-plot cutting trials with stubble turnip (B. campestris ssp. rapifera cv. Ponda), forage rape (B. napus ssp. biennis cv. Canard) and fodder radish (Raphinus sativus cv. Neris) for 3 years, 1975–77, samples being taken from October to December or January each year to cover the likely period of utilization by grazing lambs. Except for the first year, Appin proved to yield less DM than Ponda, and be inferior in digestibility and metabolizable energy (ME) content, though N contents were on occasion higher. Canard had the highest overall ME content. In dry conditions in autumn 1977, Ponda proved the more reliable crop, suffering less depression in yield than other species. Anti-metabolite contents were determined in freeze-dried samples taken in winter 1976-77 and showed Canard to have the most brassica anaemia factor (S-methyl cysteine sulphoxide): contents of thiocyanate were generally similar between crops.As the degree of utilization of such forages when grazed can outweigh differences in recorded above-ground DM yields from cutting trials, it was considered that claims of better root anchorage and hence better utilization for Appin warranted evaluation in a grazing trial.

Notes: Two grass silages made from perennial ryegrass, and with D-values of 0·216 and 0·255, were offered ad libitum to 18 Ayrshire cows in two feeding experiments. On the control treatment the silages were supplemented with soybean meal only, and on the other two treatments with equal weights of DM from either barley or dried molassed sugar-beet pulp plus the same weight of soya as on the control treatment. The daily intakes of silage DM were not significantly different on the barley and beet-pulp treatments, and, on average, the intake of silage DM was reduced by 0·24 and 0·20 kg by feeding 1 kg barley and beet pulp DM respectively.The daily milk yields were not significantly different on the barley and beet-pulp treatments with mean values of 19·2 and 19·2 kg per cow respectively compared with 17·2 kg on the control treatment. On the barley and beet-pulp treatments the fat, SNF, CP and lactose concentrations in the milk and the live weights of the cows were not significantly different. It is concluded that the barley and beet pulp had similar feeding values and replacement rates when used as supplements with grass silage, and that the two feeds were interchangeable on an equal DM basis.

Notes: An experiment examining the relationship of daily herbage disappearance (DHD) and daily herbage allowance (DHA) is described. Cows with calves were grazed at three stocking rates on Kleingrass and Coastal Bermudagrass pastures. DHD and DHA were monitored at 14-d intervals. A significant positive linear relationship was noted between DHD and DHA (P〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:01425242:GFS9:les" location="les.gif"/〉0·25). Equations derived for Coastal Bermudagrass and Kleingrass were not significantly different and resulted in a combined equation Ŷ= 0·275X + 0·209 with an r2 vaiue of 0·27. As DHA exceeded 6–9 kg DM per 100 kg live weight, efficiency of defoliation by the cows and calves declined.

Notes: The effects of five herbicides on seed yield and viability of perennial ryegrass cv. S24 were tested at two sites. Benzoylprop-ethyl, chlorfenpropmethyl, difenzoquat, ethofumesate and flam-prop-isopropyl were safe to use at doses recommended for use in other crops. When applied at three times the recommended dose, only difenzoquat reduced the yield and germination of seed and benzoylprop-ethyl reduced seed germination. The recommended doses of difenzoquat and ethofumesate were safe when applied on cv. Barlenna at different growth stages. Difenzoquat reduced seed yield only after three times the recommended dose was applied to tillered plants. Ethofumesate, even at three times the recommended dose, did not affect seed yield but plant numbers were reduced by early treatment. The results suggest that the herbicides tested may be safe to use in perennial ryegrass seed crops at the recommended doses but more work is needed on the safety of difenzoquat in relation to crop growth stage.

Notes: Les différentes sources d'erreurs de la mesure gravimétrique sont examinées. Leur connaissance a une importance particulière dans les prospections de surface, dites “microgravimétriques”.Les auteurs démontrent, expériences à l'appui, que toutes précautions prises, la source la plus fréquente d'erreurs de mesure en microgravimétrie est une mauvaise estimation de la dérive.Les auteurs exposent alors un processus de mesure et d'interprétation dont le but est une meilleure estimation de la dérive. La justification théorique et expérimentale du processus est donnée. La méthode implique une prise de mesure suivant une répartition spatiale aléatoire ou semi-aléatoire. Un cas réel est décrit.

Notes: A number of time-domain IP traverses were carried out across two parallel mineralized sheets in the Lower Pillow Lavas, near Mitsero, Cyprus with Huntec Mark III equipment using the pole-dipole array. In one sheet the mineralization was disseminated (2%S), and in the other it was massive (30%S). The transients were recorded at separation n= 2 at a number of points to give the complete shape of the curves. The normalized time integrals were anomalous over the two sheets, but were not significantly different; the highest values being observed over the disseminated sheet. Both sheets were also associated with high electromagnetic components of the decay curve. The chargeability and resistivity values obtained over the disseminated body were considerably higher. The metal factor was also of value in discriminating between massive ore, disseminated mineralization, and barren rock. The values of P2 and P3 for the two bodies were also compared (P2 and P3 are defined by〈displayedItem type="mathematics" xml:id="mu1" numbered="no"〉〈mediaResource alt="image" href="urn:x-wiley:00168025:GPR906:GPR_906_mu1"/〉where M1 to M4 are the amplitudes of the decay curve at 55, 130, 280 and 580 ms respectively). For the massive ore, P was inversely related to M, but for the disseminated ore P was independent of M. Four simple parameters from the decay curves show that indices of curve shape offer the best prospect of grade discrimination.

Notes: Large gravity platforms are often used as alternatives to the more conventional pilesupported structures in hydrocarbon exploitation. A gravity structure, as opposed to the piled structure, is sitting on the sea floor by virtue of its weight and base width; as such it poses considerable problems for the site investigation engineer. One such problem is the calculation of the settlement of the structure and its time history; these depend upon the permeability and compressibility of the soil and its drainage conditions. The required data are usually obtained by sampling for subsequent laboratory testing. The collection of an undisturbed sample is beset by problems so that the consolidation behavior of the foundation material can only be inadequately assessed by laboratory testing. However, a series of laboratory consolidation experiments during which seismic velocities have been measured on the sample as consolidation proceeds shows that it is possible to reconstruct the stress-strain and time-dependent curves from the seismic data, once the initial void ratio and permeability of the soil are known. This leads the way to an in situ technique for predicting settlement using a combination of geophysical techniques (electrical resistivity and seismic velocities) to obtain the required engineering properties.

Notes: An underground gravity study was carried out under extreme conditions of the Alpine regions. The lead–zinc mine Bleiberg, Carinthia, was selected as an example to show the possibilities and limitations of the subsurface gravity method. For in situ density determinations, gravity measurements were made in two vertical mine shafts passing through Triassic sedimentary rocks of the Bleiberg Unit. The main prblem in gravity data reduction in extremely rugged topography is the accurate calculation of the terrain effect on underground stations. A general discussion of the various corrections required for the gravity measurements in the mine is presented. The mean interval densities in the two shafts, in limestone, dolomite, and schists formations, were determined as 2.76 and 2.77 g/cm3, respectively, with an accuracy of better than 0.01 g/cm3 for a depth interval of 50 m. The interval densities provide valuable information about the lithological and structural changes in the shaft surroundings and also agree well with the representative hand sample densities.In the second part, the applications of subsurface horizontal gravity surveys in exploration are discussed. Since the influence of topography is less underground because of the greater distance to the surface, subsurface surveys have definite advantages over surface surveys and can be very helpful in locating anomalous density zones in the mines. An example of gravity survey with a station spacing of 10 m at a depth of about 540 m is presented.

Notes: Lateral inhomogeneities generate fluctuations in the traveltime of seismic waves. By evaluation of these traveltime fluctuations from different source and receiver positions, lateral inhomogeneities can be located using a pseudo inverse matrix method (Aki, Christoffersson and Husebye 1977). The formulation of the problem is possible for transmitted waves as well as for reflected and refracted waves. In reflection seismics this method is of importance, if no reflections from the inhomogeneities themselves, but only reflections from lower boundaries can be observed.The basic assumptions for the mathematical formulation are (1) the average velocities and depths of the reflecting horizons are known already from standard processing methods, and (2) the traveltime residuals are due to lateral velocity changes between different reflectors or between reflectors and the surface. The area of the earth to be considered is divided into layers and the layers into rectangular blocks. The parallel displacement of a ray after passing a disturbed block is neglected, only the traveltime residual is taken into account.In this paper the method and its application to data obtained with two-dimensional models are described.

Notes: The electric and magnetic fields generated by horizontal electric and vertical magnetic dipoles lying on the surface of a conducting medium with horizontal anisotropy are investigated. Full expressions of their Fourier transforms are given, and the fields for a vertical magnetic dipole are calculated numerically. The radial and vertical magnetic components are found to be independent of the receiver-transmitter direction, whereas the other magnetic and electric components strongly vary with this direction. These results give useful criteria for defining the direction and amplitude of anisotropy from ground data; a ground experiment on fissured limestone was found to confirm the expected variations of the various field components. It is believed that this electromagnetic method can be used in order to provide information about the direction and amplitude of electric anisotropy.

Notes: On the basis of known relationships between various elastic moduli and porosity in a porous medium and of various parameters from well-logs, the reflection coefficient for normal incidence of P-waves is compared to that of S-waves. If pores contain gas, the reflection coefficient in S is much smaller than that of P but shows large differences for different gas concentration in one of the two layers while the reflection coefficient in P is insensitive to the gas concentration. It is found that the ratio of the two reflection coefficients provides a powerful tool for discriminating between layers of different degrees of gas concentration and for the extension of the sensitivity of the bright-spot technique to greater depths.

Notes: The laterites in Burundi, which are formed by weathering of ultrabasic rocks, show a complete profile with the following horizons: canga, the ferruginous crust capping, ferralite, consisting essentially of iron hydroxides, and saprolite, which contains a large quantity of hydrosilicate minerals. Nickel bearing minerals occur in the saprolite and the lower portion of ferralite.Resistivity well-logging and resistivity sounding indicated that the electrical properties of rocks depend upon their composition: Canga and ferralite showed high resistivities of 6,500 Ωm and 800 Ωm, respectively. The resistivity of saprolite was found to be much lower, between 10 Ωm and 20 Ωm. The laterite is underlain by resistive peridotite. The chargeability of saprolite was found to be lower than that of the upper horizons and the bedrock.Electrolytic conductivity of laterite, which depends on the geometry of the deposit, was found to be low, because the laterite contains moisture and ground water, which are highly resistive. The relatively high conductivity of saprolite is caused by nickeliferous hydrosilicates, which exhibit the electrical properties of clay minerals, with an apparent maximum conductivity of 0.25 S/m. The conductivity of saprolite corresponds to a concentration between 30% and 50% of conductive silicate minerals distributed in the pore space of deposit. A nickel enrichment of up to 6% was estimated from the resistivity of the saprolite.Prospecting for laterites by electrical sounding showed that the development of laterite horizons in a nickel deposit correlates with the surface morphology of weathered ultrabasic massif. Thus the method can be used in preliminary exploration of such deposits.

Notes: Thirty-eight gravity method estimates of the depth to the pre-Cenozoic surface under Yucca Flat are used to determine the statistical accuracy associated with the gravity method. Results indicate that the gravity method tends to overestimate the depth to the pre-Cenozoic surface, on the average, by 3.5 m with a standard deviation of 75.2 m. No significant change of this statistical estimate was observed with (1) depth, (2) location, or (3) date when the gravity-method estimate was made.

Notes: Since its development some thirty years ago, the airborne electromagnetic (AEM) method has been primarily used as a tool for mineral prospecting. However, advanced AEM systems are capable of other tasks, such as geological mapping and groundwater exploration. Excellent correlation between maps of apparent conductivity and geological maps was observed in several regions of Brazil where AEM surveys were performed. The degree of correlation seems to depend on the local climate. In humid and subhumid tropical regions, a weathered layer develops whose thickness and conductivity depend upon bedrock lithology. Therefore certain lithological types can be recognized from their conductivity signature; e.g., granites and Precambrian coarse clastic rocks are resistive, metavolcanic (particularly mafic) and volcanic rocks are conductive, Phanerozoic sediments are generally highly conductive.Two geophysical surveys are analyzed in the paper. The first was conducted with the time-domain, towed-bird AEM system in the Itapicuru greenstone belt in the state of Bahia. The apparent conductivity map correlated better with the local lithology than the magnetic map. Results of the AEM survey were successfully used to improve the regional geological map. A helicopter EM system was used in the second survey, which covered a portion of the Precambrian shield of Rio Grande do Sul. Also in this region ground checks confirmed the usefulness of conductivity surveys in geological mapping.The technique outlined in the paper holds great promise for countries of humid tropical climate, where few outcrops exist and access is often difficult. The tests performed in Brazil indicate that by executing AEM/aeromagnetic surveys during initial stages of mapping and exploration programs, time and expenditure required for geological field work can be considerably reduced. The resulting geological maps are more accurate and the inventory of mineral occurrences becomes more complete.

Notes: The examination of apparent resistivity space sections over two-dimensional targets requires the accumulation of large amounts of data, if the resistivity field is to be adequately described.Whilst such data may be obtained from an intensive sounding traverse in the field, it is desirable for interpretation purposes to be able to generate such space sections for a range of model variations.Within their limitations, tank analogs can be used to provide such interpretation material, but the collection of data can itself be time-consuming. In this paper, an account is given of the development of an automated tank analog, where an entire space section can be scanned and the output obtained in paper tape format for later processing on a digital computer. The resistance measurement accuracy attained is comparable with normal field measurement accuracy.A practical example of the use of this analog in investigating the problem of resolving and discriminating between two horizontal cylindrical tunnels is given. This problem is basic to an understanding of the minimum size and disposition of targets which can be observed on a space section. The square array has been used in this example because of its good resolution properties in general prospecting rather than its particular suitability for the targets investigated. The directional response of the array is also illustrated and discussed.

Notes: The “Autorité des amenegements des valées des Voltas (AVV)” is establishing new rural settlements in the Volta valleys. First, a survey of available water supplies is performed. Economic aquifers in Precambrian terrains are deep (15–50 m) and usually occur in fractured zones accompanying faults. Such zones can be identified on aerial photographs, but their precise location on the ground is virtually impossible by visual means. Because of the small size of the aquifers, a location error of 5 m can make the difference between a productive well and a dry hole.Traditionally, resistivity profiling has been used as the means of locating the fractured zones in the field. Our studies suggest that the task can be performed faster, cheaper and more accurately by VLF and EM methods. Because of the limited choice of transmitting stations reccivable in Upper Volta, the VLF method is not sufficiently sensitive to detect conductors with a strike between 45° and 105°. The results obtained with a multifrequency, horizontal-loop EM (HLEM) system were satisfactory in all investigated areas. During the 1980 field season, 35 target areas were surveyed. Of the 24 holes drilled so far, 23 are productive.The weathered layer is a source of distinctive HLEM anomalies, which are characteristic of the underlying rocks. Therefore, different interpretational procedures had to be developed for granitic and volcano-sedimentary areas. Despite the high background level of in-phase and quadrature components, which varied with thickness and conductivity of the weathered layer, aquifers could be detected at a depth greater than 30 m. Attempts were made to interpret the HLEM results quantitatively using two models: a three-layer medium and a valley discontinuity. The latter model is more realistic, but more scale modelling will have to be performed to permit development of viable interpretational procedures. Meanwhile, phasor diagrams based on drilling and resistivity sounding data can be used to estimate the aquifer depth.

Notes: A type of iterative deconvolution that extracts the source waveform and reflectivity from a seismogram through the use of zero memory, non-linear estimators of reflection coefficient amplitnde is developed. Here, we present a theory for iterative deconvolution that is based upon the specification of a stochastic model describing reflectivity. The resulting parametric algorithm deconvolves the seismogram by forcing a filtered version of the seismogram to resemble an estimated reflection coefficient sequence. This latter time series is itself obtained from the filtered seismogram, and so a degree of iteration is required. Algorithms utilizing zero memory non-linearities (ZNLs) converge to a family of processes, which we call Bussgang, of which any colored Gaussian process and any independent process are members. The direction of convergence is controlled by the choice of ZNL used in the algorithm. Synthetic and real data show that, generally, five to ten iterations are required for acceptable deconvolutions.

Notes: The digestibility of herbage selected by dairy cows, milk-fed calves, weaned calves and wether sheep was examined on four occasions each day as they strip-grazed together a daily allocation of herbage. The average quality of the material selected by each group was similar. Organic matter digestibility of the herbage selected declined from 0·274 to 0·223 as the average height of the sward fell from 16 to 6 cm; this decline was slightly more rapid for the cows than for the other stock. A similar trend was also evident in samples cut from the sward to simulate the horizon removed prior to each sampling time.

Notes: Grass silage made in May from S24 perennial ryegrass had a DM concentration of 262 g kg-1 and an in vitro D-value of 0·698, and was given ad libitum to twelve Ayrshire cows in a 16-week feeding experiment. In addition supplements of hay with a mean in vitro D-value of 0·603 were offered in one of three forms—long, chopped (12·1 mm) or ground (0·80 modulus of fineness) and cubed—and of concentrates given at either 2 or 4 kg per 10 kg milk. Hay averaged 18·2% of total forage DM intake with mean daily intakes of 1·28, 1·22 and 2·26 kg DM per cow in the long, short and ground forms respectively. The highest daily intakes of forage, i.e. silage plus hay, occurred on the ground hay treatments, with values of 10·24 and 9·25 kg DM per cow on the 2 and 4 kg concentrate treatments respectively. The mean daily milk yields were 18·2,18·2 and 19·2 kg per cow on the long, short and ground hay treatments respectively but the increase in yield with the ground hay was only significant at the low level of concentrate intake. The hay treatments had small and non-significant effects on milk composition. It is concluded that ground hay was superior to either long or chopped hay as a supplement for silage, but the small advantages depended on the level of concentrate intake.

Notes: Book review in this article Energy from Biomass in Europe Edited by W. Palz and P.

Notes: The water loss from tall fescue cv. S170, perennial ryegrass cv. S24, Italian ryegrass cv. RvP and timothy cv. S352 when dried as a thin layer under controlled conditions at 20°C and r.h. 50% is described. Comparisons were made on six occasions between mid-April and mid-June. Tall fescue dried faster than the other species and the time to reach a water concentration of 0·2 g water per g dry matter varied little between the six harvests. In contrast, the drying time for the ryegrasses and timothy increased to maximal values in mid-May and then fell. Drying time was dependent on the initial water concentration of the grass, the ratio of leaf to stem and on the amount of true stem exposed to the drying environment. The practical implications in relation to haymaking are discussed.

Notes: The results are reported of an examination of detailed measurements on the ingestive behaviour of calves and lambs in response to variations in the surface characteristics of swards under strip-grazing and continuous stocking managements. It is shown that intake per bite and the short-term rate of herbage intake were both sensitive to the height of the surface horizon above ground level but, at least under strip-grazing management, not to variations in herbage density in the grazed horizon. The rate of biting was less sensitive to variations in sward conditions, particularly under strip-grazing.Both intake per bite and rate of intake were more sensitive to variations in grazing height under strip-grazing, where sward changes were rapid, than under continuous stocking, where they were slow. Under continuous stocking, ingestive behaviour was more sensitive to changes in sward conditions in lambs than in calves.

Notes: In an experiment of four years duration, the competitive relationships between three cultivars of white clover (Trifolium repens L.) and ten cultivars of perennial ryegrass (Lolium perenne L.) were studied under a N fertilizer regime of 200–240 kg ha-1 a-1. The clover cultivars were selected to embrace the various leaf sizes from medium large to small and the ryegrasses included early, mid-season and late cultivars with a known range of persistence.During the experiment there was a progressive decline in the contribution of clover, though the different characteristics of each of the clover and ryegrass cultivars produced substantial deviations from the average trend. The clover cultivar Kersey was significantly more aggressive towards the companion grass cultivars than either S100 or S184. It produced consistently greater clover contribution to total yield than the other two cultivars and significantly depressed the yields of some of the companion grass cultivars. There was evidence that compatibility of the ryegrass cultivars with clover was inversely related to persistence; the non-persistent ryegrass cultivars S321 and Presto consistently produced lower grass yields than the more persistent cultivars and consequently permitted greater clover contribution. In the second and third years yield substitution effects between clover and grass components substantially reduced differences in the total grass-clover yield.The interactions revealed in the experiment showed that both ryegrass and clover cultivars have the potential to influence each other when in association although, with minor exceptions, total annual yields were similar for all grass and clover mixtures at the moderately high level of N applied.