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Several species of Mesozoic megaspores that are sculptured with globular, often gemmate elements are sufficiently distinct from most verrucate forms to warrant their inclusion in a genus other than Verrutriletes. Cabochonicus is erected to accommodate them with C. (al. Verrutriletes) carbunculus as the type species. The form of the gemmae, which have a glossy appearance, has been the subject of past debate with one interpretation being that they are the manifestation of fungal attack rather than sculpture. Evidence from ultrastructural studies suggests, however, that they are exinal excrescences. The spores are assumed to be the products of heterosporous lycopods and the structure of the wall layers may indicate selaginellalean affinities. The plants are more likely to have been terrestrial than aquatic or semi-aquatic.

A dichotomous key to the recognition of 86 Normapolles and morphologically similar pollen genera is presented. The key is accompanied by line drawings of each genus and an illustrated glossary of descriptive terms.

The remains of phytoplankton occur at many horizons in the Wealden succession of southern England. Some of these are dinocysts that are identical to known marine Early Cretaceous species but the sedimentological and palaeontological associations of others indicate fresh-water origins. Species of the cyst genera Australisphaera, Ripea and several new forms are among the members of this group. They commonly occur together with the chlorococcalean algae Pediastrum, Scenedesmus, Tetraedron and Tetrastrum . The last of these has not had a fossil record hitherto, and both Scenedesmus and Tetraedron have hardly ever been reported previously from pre-Quaternary deposits. These findings contradict the widely held opinion that dinoflagellates did not occupy freshwater habitats until the beginning of the Cenozoic Era.

The megasporesArcellites plicatus sp. nov. and A. yiminensis sp. nov. and adherent microspores Crybelosporites minor (Qian and Wang 1981) comb. nov. and C. astrictus sp. nov. are described and illustrated from the Damoguihe and Yimin Formations of the Jalainor Group of northeast Inner Mongolia. Transmission electron micrographs of thin-sectioned specimens reveal a close similarity between the wall structure of the megaspores and microspores, thus lending further support to previously recognised indications of a natural relationship between Arcellites and Crybelosporites. Comparison with the morphology, and consideration of the stratigraphic distribution of all known species of Arcellites suggest that the strata from which the new taxa were recorded range from Barremian to Aptian in age. Single specimens of Arcellites sp. cf. A. rugosus Singh 1964 and an unnamed species of the genus are also described, and Triletes fecheri Huckriede 1982 is reported to be a junior synonym of Arcellites pyriformis (Dijkstra) Potter 1963.

Pollen grains referable to the Normapolles group first appeared during the Cenomanian. They diversified rapidly through the remainder of the Cretaceous and during the early Palaeogene, but by the end of the Eocene they were virtually extinct. They were most numerous in a province which extended from what is now West Siberia across Europe to eastern North America. The Western Interior of North America and West Siberia are considered to delimit the longitudinal boundaries of this province. These areas were submerged during the Late Cretaceous and formed physical barriers to wider dispersal of many Normapolles-producing plants. The Normapolles that have been reported from further afield comprise only minor elements of palynofloras except locally in a few areas where they are apparently relatively abundant. Such records do not invalidate the Siberian and American longitudinal limits but they do require that the concept of the province be altered somewhat to indicate region within which Normapolles are more consistently abundant than elsewhere. Climate must have been as significant an influence on the evolution of the parent plants as it appears to have been in determining the northern and southern boundaries of the province, however vaguely defined these are at present. Palynological analyses of core and cuttings samples from the U.K. continental shelf have helped to refine the northern limit to some extent. Until recently, published maps have included both Svalbard and Greenland in the Normapolles Province. Whilst possibly correct for some of the early Tertiary, Late Cretaceous (Campanian-Maastrichtian) strata in the Northern North Sea and west of the Shetland Islands have yielded Aquilapollenites, Wodehouseia and other taxa typical of the Aquilapollenites Province. The transition between the flora of this boreal region and the European part of the Normapolles Province, which is known to extend as far north as southern Sweden, would thus appear to lie approximately on the latitude of the central North Sea.

The morphological resemblance between the sheaths of modern Gloeotrichia and Early Cretaceous Celyphus rallus Batten strongly suggests that the latter is a Mesozoic relative of extant blue-green algal species belonging to the family Rivulariaceae. The fossils are typically encountered in argillaceous sediments that were deposited in non-marine environments. When living, they could have been planktonic, but because all the colonies recovered to date are compressed, the possibility that they formed hemispherical rather than spherical masses and grew attached to a substrate cannot be entirely excluded. In common with many blue-greens, C. rallus may have been a pioneering species, perhaps at the transition from brackish to fresh water deposition. Local abundances might well reflect “blooms” in neutral or slightly alkaline conditions at this juncture, but could also be connected with seasonal changes and fixing nitrogen from the atmosphere in nitrogen-poor environments.

This paper presents data on the stratigraphic ranges of all known Mesozoic and Tertiary megaspores from around the world and demonstrates the potential of these palynomorphs for dating and correlating sedimentary sequences. Forms referable to more “natural”; genera such as Ariadnaesporites and Paxillitriletes, as opposed to those that are based solely on sculptural morphology, are particularly important because not only are they among the most reliable of biostratigraphic indicators but they also have the greatest value to biologists concerned with the evolution of heterosporous plants. There is, however, much work to be done before megaspores can be used on a regular basis for solving geological problems.

A number of dinoflagellate cysts occur in Wealden deposits that are considered to have accumulated in fresh to slightly brackish water conditions. Most of the forms that have been encountered in the Weald Clay Group (Hauterivian-Barremian) of southeast England and the Wessex and Vectis Formations on the Isle of Wight are described and/or illustrated in this paper. Of these, the following are new: Australisphaera longicornis sp. nov., Cassiculosphaeridia parvula sp. nov., Microdinium? fibratum sp. nov., Kallosphaeridium? inornatum sp. nov., K.? spongiosum sp. nov., Pannosiella perforata gen. et sp. nov., Vectensia varians gen. et sp. nov., Corculodinium uniconicum gen. et sp. nov., Lobionella hirsuta gen. et sp. nov. and Spicadinium akidoton gen. et sp. nov. Commonly associated with several of the cysts are chlorococcalean algae referable to the genera Botryococcus, Tetraedron, Pediastrum, Scenedesmus and Tetrastrum . Four of these are also newly diagnosed, namely Tetraedron paraincus, Scenedesmus bifidus, Tetrastrum ciliatum and T. multifilorum .

The preparation of the unsaturated hydroperoxides (3,4,5,6 and 7) by the sensitized photooxidation of the 1,4-diene(1) and the 1,5-diene(2) is described, together with the attempted free-radical cyclisation of these.

The condensed-phase thermal decomposition of aliphatic nitrate ester explosives is generally autocatalytic. The object of this article is to show that the agent of the autocatalysis is not the product NO2, as is generally believed, but to suggest that it may be the product formaldehyde.

Megaspores are recorded from several localities in the Thanet and Reading Beds (upper Palaeocene) of southern England. Evidence from their taxonomic affinity, colour, compression and state of preservation indicates three separate groups: two reworked from lower Westphalian Coal Measures and Lower Cretaceous sequences, respectively, and one of contemporaneous forms. Mesozoic megaspores redeposited in the British Tertiary have not previously been recorded. Isolated Carboniferous forms have been found before but their possible value in provenance studies has not been fully explored. The new material includes a diverse assemblage of numerous Westphalian and Lower Cretaceous forms from a single horizon in the Thanet Beds. Of possible source areas it seems most likely that these spores were reworked from the Moray Firth Basin, and elsewhere near the present eastern coast of Scotland, by means of longshore drift following a roughly N–S palaeocoastline. Evidence from other studies of heavy mineral assemblages and palaeogeography also indicates derivation of Thanet Beds sediments by this means. The Cenozoic megaspores include an Azolla (water fern) and two distinct lycopsid forms, one probably of selaginellalean and one of isoetalean affinity. These latter provide the first clear evidence of lycopsids in British Tertiary floras and expand our knowledge of freshwater macrophytes of that time. The assemblages of Minerisporites show morphological trends which may prove to be of biostratigraphic value.

The poorly consolidated clastic sediments of Late Cretaceous age in the vicinity of Asen, southern Sweden (Scania) are noted for the variety of fossil flowers and Normapolles pollen grains they have yielded. Megaspores have also been recovered from a number of horizons. Comments on, and illustrations of all but a few indeterminate remains of these are provided in this paper, and four new species, Bacutriletes ferulus, B. majorinus, Erlan‐sonisporites scanicus and E. septus, are erected. Comparison of the total recovery with the relatively small number of Late Cretaceous assemblages that have been described from elsewhere reveals only a few taxa in common. As a result, it is not possible to improve on the late Santonian‐early Campanian age determination that has already been established for the Asen deposits. It is reasonable to infer from the wall structure of the majority of the spores that they were shed by plants of either selaginellalean or isoetalean affinity. Their distribution within the A...

Rationalization of the taxonomy of pollen grains referable to Papillopollis has been necessary so that the majority of specimens encountered in the Senonian succession of Portugal can be identified. Revised diagnoses are provided for P. aradaensis Kedves & Pittau, P. aveiroensis Kedves & Pittau, P. minimalis Pacltova & Krutzsch, P. rugulatus Kedves & Pittau and P. santonius Pacltova & Krutzsch; one new species, P. barbosae, is erected. The degree of morphological variation allowed for these species is greater than in previous descriptions of forms of Papillopollis and enables the removal of seventeen other taxa which lack reliable distinguishing characters by placing them in synonymy. The sculpture of the pollen grains described ranges from essentially granulate to minutely papillate. The sexine at the poles is typically fissured or reduced to small granular or papillate masses or bodies, but can be absent altogether. These areas of modified exine may have had a harmomegathic function. Thin secti...

We describe here the general operation of the Oxford Radiocarbon Accelerator Laboratory which has now been dating routinely for 18 months.

The auxin transport inhibitors 2, 3, 5-triiodobenzoic acid (TIBA) and naphthylphthalamic acid (NPA) inhibited adventitious root formation (ARF) induced by indol-3-butyric acid (IBA) on cuttings from etiolated mung-bean seedlings floated on solutions of the growth regulators. The concentrations of TIBA and NPA required for a 25 per cent reduction in ARF with 10 μM IBA were estimated by linear interpolation to be 11.3 μm and 0.42 μM respectively. NPA is a particularly potent inhibitor of IBA-induced ARF. The inhibitory effect of either compound was reversible by higher concentrations of IBA. NPA had no effect when applied after the auxin treatment. The inhibitory effects of TIBA or NPA could not be explained by effects on the uptake or metabolism of [2-14C]IAA. Considering this and other evidence, it is suggested that NPA and possibly TIBA are acting as specific antagonists of auxin in the induction of ARF.

Spores of ferns and allied plants, and micro-algae frequently occur in abundance in Quaternary deposits, but their palaeoenvironmental significance is seldom evaluated. This paper presents morphological descriptions of spores of Selaginella sinensis (Desv.) Spring, 1843 (Selaginellaceae) and Ceratopteris cf. thalictroides (L.) Brongniart, 1821 (Parkeriaceae) and the algae Pediastrum boryanum (Turpin) Meneghini, 1840, P. simplex Meyen, 1829, P. integrum Nageli, 1849 (all Hydrodictyaceae), Spiniferites Mantell, 1850, emend. Sarjeant, 1970 (Spiniferitaceae) and Concentricystes Rossignal, 1962, emend. Jiabo, 1978 (systematic position unclear), and discusses their occurrence in mostly Quaternary sedimentary successions. All are closely associated with aquatic habitats. Extant Selaginella sinensis often colonizes fairly wet hillsides and gaps between rocks, and shady sides of ravines and slopes; it is also found within thickets of trees and shrubs (boscages) and in forests with calcareous soils. Ceratopteris thalictroides, Pediastrum and Concentricystes inhabit freshwater lakes and both natural and artificial wetlands, such as paddy fields and ditches. Spiniferites is a salt-water genus and usually associated with the marine realm. Fossil and subfossil representatives of all of these taxa can be useful proxies of biodiversity and, therefore, also important for determining environmental conditions during the Quaternary period.

Six boys with fragmentation of the proximal pole of the patella are reported; the condition was bilateral in one. Four of the six presented with symptoms of Osgood-Schlatter's disease or Larsen-Johansson disease of the same or of the contralateral knee, but they had no symptoms or signs relating to the proximal pole of the patella; one also had features suggesting minimal chondromalacia patellae. Two boys had no objective abnormality in either knee. It is suggested that the fragmentation may be a further form of traction osteochondritis of the attachments of the quadriceps mechanism. Attention is drawn to its characteristic radiographic appearance, its association with other forms of juvenile traction osteochondritis (which are commonly symptomatic), and to its occurrence in boys aged 10 or 11 years.

The Kap Washington Group of post-Palaeozoic explosive volcanic rocks was discovered in 1969 on the north coast of Greenland. Although there have been uncertainties regarding their age and chemical character, they have featured prominently in geotectonic reconstructions of the Arctic regions-in recent interpretations as products of the Yermak hot spot, generated on the Nansen spreading axis during the opening of the Eurasia Basin. We present here new evidence which confirms the volcanicity as end-Cretaceous in age and of peralkaline type. We show that a direct connection with the Yermak hot spot is improbable and infer that the volcanic rocks were generated in a continental extensional rift environment before the break-up of the Laurasian plate in the Arctic. Their age helps to constrain the timing of this poorly understood event.

Patients with fulminant hepatic failure have a bleak prognosis. As a result there has been continued research for the development of artificial liver support devices (Brunner and Schmidt, 1981). However, the assessment of any liver support system is difficult because of uncertainties regarding the aetiology, pathogenesis and outcome of hepatic coma. The design and timing of the use of these systems have thus been largely empirical.

Valproic acid is a very commonly used anti-epileptic drug which requires regular monitoring. The authors consider the assay of this drug by means of 2 techniques: Syva's homogeneous phase immuno-enzymatic technique adapted by Du Pont de Nemours for his automatic clinical analyser and high performance liquid chromatography (HPLC). The precision of the immuno-enzymatic technique is insufficient for concentrations of valproic acid of between 70 and 35 mumol/l (coefficient of variation: 27.0 and 22.0 per cent respectively). The precision of this method for concentrations of valproic acid of 45 and 205 mumol/l is good (coefficient of variation: 8.5 and 8.2 per cent respectively). For concentrations of valproic acid of between 347 and 867 mumol/l, the precision of the immunoenzymological is very good and comparable to that of high performance liquid chromatography (coefficient of variation: 5.9 and 3.8 per cent). For all of the above concentrations of valproic acid, the coefficients of variation obtained with high performance liquid chromatography were less than 5 per cent. Comparison by means of the t test for paired series demonstrated a significant difference between the results of the 2 techniques, with a risk of error of p less than 0.01. The coefficient of correlation between the 2 techniques was 0.96. However, Eksborg's representation shows a difference between the 2 assay methods for concentrations of valproic acid of less than 200 mumol/l, with higher values with HPLC.

Photochemical reaction of the trans-fused bicyclic ketone (1) in solution gave the unsaturated aldehyde (4), whereas irradiation of the cis-fused isomer (2) in methanol led to inefficient photoreduction.

The role of mammalian bone marrow in generating surface IgM (sIgM)-bearing B lymphocytes is reviewed. Precursor cells in the marrow give rise to large, rapidly dividing cells bearing free cytoplasmic mu chains (c mu). The progeny of the large c mu+ cells form a population of small, nondividing c mu+ cells that mature into small lymphocytes, progressively expressing sIgM and other B-cell surface membrane components. Newly formed sIgM+ cells soon migrate through the bloodstream to the spleen and other lymphoid tissues, where they may die after a short lifespan or be activated to produce antibody molecules. The large-scale lymphocytopoiesis in the bone marrow thus maintains a population of rapidly renewed virgin B lymphocytes in the peripheral lymphoid tissues. This process continuously creates and selects B cell clones with the wide range of antibody specificities necessary to mediate primary humoral immune responses through postnatal life. A technique for perfusing radiolabeled anti-IgM antibodies in young mice has now permitted sIgM+ cells to be detected radioautographically in histological preparations of bone marrow under the electron microscope. Small sIgM+ lymphocytes are situated either singly or in small groups throughout the extravascular hemopoietic compartment of the bone marrow, often near sinusoid walls adjacent to late erythroblasts and reticular cells. Some regional concentrations of sIgM+ cells are apparent. sIgM+ cells also appear in transit through the sinusoidal endothelium and are markedly concentrated in the lumen of some sinusoids. Intrasinusoidal sIgM+ small lymphocytes have high densities of sIgM and long microvilli, on which sIgM molecules are concentrated. These studies reveal the localization and cell associations of specifically identified sIgM+ small lymphocytes in the extravascular marrow compartment and suggest that these cells may also undergo a transient intravascular storage and maturation phase. Use of this in vivo immunolabeling technique to detect other cell-surface markers may further elucidate the microenvironmental basis of B lymphocyte genesis in the bone marrow.

Rooting responses and ethylene production by hypocotyl cuttings from etiolated mung-bean seedlings treated with the auxins α-naphthaleneacetic acid, γ-(indole-3)-n-butyric acid (IBA) and 2,4,5-trichloro-phenoxypropionic acid were determined. There was no relationship between the abilities of the auxins to induce root formation and their capacities for inducing ethylene production. Studies with mixtures of 3-indoleacetic acid, a poor stimulator of rooting but an effective inducer of ethylene production, and IBA, an effective rooting stimulator but a poor inducer of ethylene production, exposure of cuttings to ethylene or (2-chloroethyl) phosphonic acid (Ethephon), hypobaric storage (150 mb) of treated cuttings, and exposure of auxin-treated cuttings to 7% CO2 also indicated that ethylene is not directly involved in initiation of adventitious roots in this plant material.

Many associations between components of palynological preparations and lithofacies in the Purbeck Beds and Wealden (uppermost Jurassic-Lower Cretaceous) of southern England have been recognised and are progressively being employed to aid the identification of depositional environments. Detailed sampling has led, in particular, to the recovery of numerous assemblages of phytoplankton. All are taxonomically restricted and none has a fully marine aspect. Both numerical and compositional variations suggest near-marine to perhaps only slightly brackish and freshwater conditions of deposition. Selected aspects of these and other palynofacies studies are discussed and illustrated.

This paper presents for the first time the annual suicide incidence rates of residents from four Oregon state institutions for a 5-year (1983-1987) period of time. The suicide rate for inmate-patients of the Forensic Psychiatric Program (for the care and treatment of individuals who have been found guilty of serious crime and to be mentally ill) is 820/100,000. This represents a suicide rate 51 times higher than the rate for Marion County or the state of Oregon. This is also one of the highest annual suicide rates ever reported. The suicide rate for patients of the Oregon State Hospital is 289/100,000, which is similar to other reported suicide rates in hospitalized mentally ill populations. This rate is approximately 18 times higher than the rate for Marion County or the state of Oregon. The suicide rate for inmates of Oregon's four correctional institutions is approximately 29/100,000, which is similar to other reported rates for prisoners. This rate is approximately 1.8 times higher than the rate for Marion County or the state of Oregon. The suicide rate for residents of the Fairview Training Center (for care of the mentally retarded and developmentally disabled) is zero. Language: en