Search Results - (Author, Cooperation:J. A. Jackson)

2014-06-21

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

2018-03-23

American Society of Hematology (ASH)

0006-4971

1528-0020

Biology

Medicine

Immunobiology and Immunotherapy, Transplantation, Free Research Articles, Myeloid Neoplasia

2018-12-08

American Association for the Advancement of Science (AAAS)

2375-2548

Natural Sciences in General

1471-4159

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract: Previous studies have shown that Ro 5–4864 is a potent convulsant and increases the firing rate of substantia nigra zona reticulata neurons. The pharmacologic profile of compounds that antagonize these actions suggested that the effects of Ro 5–4864 were not mediated by “brain-type”benzodiazepine receptors. We examined a number of compounds that are structurally related to Ro 5–4864 for their capacities to displace [3H]Ro 5–4864 from “peripheral-type”binding sites and their potencies as convulsants (or as antagonists of Ro 5-4864-induced convulsions). It was observed that compounds such as KW 3600 (the N-desmethyl analog of Ro 5–4864), which have very low affinities for “peripheral-type”sites, are convulsants with a potency nearly equal to that of Ro 5–4864. In contrast, compounds such as Ro 5–6900 and PK 11195, which bind with very high affinities to “peripheral-type”binding sites, are neither convulsants nor do they antagonize the convulsant actions of Ro 5–4864. Within a series of compounds that are structurally related to Ro 5–4864 there is a good correlation (r = 0.93; p 〈 0.01) between their potencies as convulsants and their capacities to displace [35S]t-butylbicyclophosphorothionate from sites that may be associated with the chloride ionophore. Thus, it appears that occupation of “peripheral-type”binding sites by high-affinity ligands may not be directly involved in the convulsant actions of Ro 5–4864 and related compounds.

Electronic Resource

1365-2214

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Psychology

Longitudinal recording of O2 saturation during night-time sleep of 82 infants show significantly more falls below 93% in females and infants of mothers who smoke. Implications are discussed.

Electronic Resource

1365-2214

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Psychology

Longitudinal day-to-day recordings of symptoms in the siblings of Sudden Infant Death Syndrome (SIDS) infant show a wide variety of symptoms varying with season and days of years. Implications are discussed.

Electronic Resource

1365-2214

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Psychology

Twins show differences in physiological maturity within and between twin sets; where one infant is 5-weeks later than its sibling; while one pair may both be slow but develop together. Zygosity, birth weight and sex may be contributory but not causative factors. How vulnerability to illness may be affected, is discussed.

Electronic Resource

1365-246X

Blackwell Publishing Journal Backfiles 1879-2005

Geosciences

We examined the seismicity of central Greece between 1890 and 1988, using macroseismic and instrumental data, to ask two questions: (1) does the seismicity of this period reveal all the major tectonic structures that are known to be active?; and (2) what are the likely strains associated with the seismicity over this period? Many known active structures have been effectively aseismic for the last hundred years, and even the inclusion of all known large events earlier than 1890 reveals no activity associated with the NE coast of Evia, Gulf of Argos, or graben NE of Mt Parnassos. It is clear that even 100 years’ data are inadequate for either a reasonable assessment of seismic risk or for a confident estimation of maximum magnitude. However, we are aware of no earthquakes in central Greece during the last 200 yr that were larger than Ms 7.0. It is probable that the maximum magnitude is restricted by the maximum length of fault segments, which appears to be around 15-20 km. The earthquakes of Ms≥ 5.8 during 1890-1988 can account for a N-S displacement of around 45-70 cm (with maximum and minimum estimates a factor of two greater and smaller than this) across part of a 1890-1900 triangulation network in central Greece that was resurveyed in 1988. The contribution of smaller events may increase this displacement by about 50 per cent. This cumulative seismic displacement is similar to that estimated from the geodetic work (about 100 cm), but a detailed comparison of the two sets of observations will be reported elsewhere. A re-evaluation of all the important earthquakes of 1890–1988 in central Greece is presented in the Appendix, which summarizes information of use to both earth scientists and engineers.

Electronic Resource

0047-2441

General, Interdisciplinary

REVIEW NOTICES

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] During the early evolution of some fold mountain belts old listric normal faults in a stretched and thinned basement beneath the sedimentary column may become reactivated as thrust faults. The reversal of motion on these faults allows considerable shortening to occur without subduction or excessive ...

Electronic Resource

1399-3054

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The induction and reversal of habituation for auxin or cytokinin have been brought about by exposure of callus tissue to low or high concentrations of the growth substance in question. Since the growth rate of the tissues must be measured in the presence or absence of the growth substance being tested, habituation can be demonstrated only in callus. However some developmental processes in the intact plant seem to imply the possible involvement of habituation-like processes in normal development. Evidence for this, and the implications for the action of growth substances in plant development are considered.

Electronic Resource

0041-0020

Architecture, Civil Engineering, Surveying

Sociology

BOOKS RECEIVED

0041-0020

Architecture, Civil Engineering, Surveying

Sociology

BOOK REVIEWS

0041-0020

Architecture, Civil Engineering, Surveying

Sociology

BOOK REVIEWS

1432-1793

Springer Online Journal Archives 1860-2000

Biology

Abstract Alternate dense and less-dense skeletal bands in massive corals have been used for many years to record the history of growth in species such as Porites lutea and Montastrea annularis, based on the assumption that one dense band and one less-dense band is equivalent to a year's growth. This report demonstrates that specimens of Porites lutea Edwards and Haime (collected from the same neighbourhood in Phuket, Thailand, from November 1983 through November 1984) produce skeletal bands asynchronously and that one year's growth in corals from certain sites may regularly consist of four bands of varying density. The annual banding pattern observed at all sites includes the deposition of a dense band in response to high sedimentation loads and, probably, reduced light levels.

Electronic Resource

1432-203X

Springer Online Journal Archives 1860-2000

Biology

Abstract Tiller-derived callus ofLolium multiflorum L. gave rise to 65 regenerants displaying variation in height, flowering time, chromosome number and alteration to the banding pattern of the isoenzyme superoxide dismutase. Plants were also regenerated from callus cultures initiated from immature embryos of the related inbreeding speciesLolium temulentum L. Progeny of the regenerated plants from this species displayed variation in height, flowering date, ear length and chlorophyll content.

Electronic Resource

1435-1536

Springer Online Journal Archives 1860-2000

Chemistry and Pharmacology

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Electronic Resource

1573-5192

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract The embryonic development of haptoral sclerites is described forGyrdicotylus gallieni, a viviparous gyrodactylid occurring in the oral cavity ofXenopus laevis laevis. Due to the protogynous life-history ofG. gallieni, two age classes of adult fluke can be distinguished by the presence or absence of a penis. Highly significant differences in the length of hamulus roots between younger and older worms indicated that some post-birth growth occurs. Dorsal and ventral root lengths also showed greater variability than other hamulus characters and were highly correlated, probably as a result of their late, simultaneous development. The allometric exponent of dorsal on ventral root length in worms without a penis was estimated to be 1.00, suggesting hamulus roots show isometric growth in youngerG. gallieni. However, in older worms with a developed penis (estimated allometric exponent = 1.29) the dorsal root increases in proportion to the ventral root (which may stop growing). Hamulus point length was significantly correlated with host body length, but there was no significant association between any hamulus character and infrapopulation size or time post-infection. Variability in haptoral sclerite measurements betweenG. gallieni from the Cape, South Africa raised on different host taxa (X. l. laevis, X. l. victorianus andX. gilli) was small, while limited data suggested that increasing environmental temperature (14, 20 and 25°C) did not produce any trend in morphometric variation. There was little qualitative variability in the morphology of sclerites from worms exposed to different hosts and temperatures, or from two distinct lineages ofG. gallieni maintained at 20°C onX. l. laevis (these also showed negligible morphometric differences). Present results indicate that environmentally-induced variability is relatively minor and that haptoral sclerite characters (with the exception of hamulus root lengths, which show considerable ontogenetic variability) should provide unambiguous information for studies of speciation inGyrdicotylus.

Electronic Resource

1573-5192

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract The great majority of the Procamallaninae occur in teleosts from tropical regions; however, representatives of this group are also frequent parasites of aquatic clawed toads (Xenopus spp.) in Africa. The taxonomic status of procamallanines from different Xenopus spp. and their geographical distribution is reviewed. Batrachocamallanus n. g. is created to include forms from amphibians with large numbers of mucrons on the female tail and relatively small body size. B. occidentalis n. sp. and B. siluranae n. sp. are described, while Procamallanus brevis Kung, 1948, originally recorded from an unidentified African amphibian, is considered a synonym of B. slomei (Southwell & Kirshner, 1937) n. comb. Due to the presence of spiral thickenings on its buccal capsule, B. xenopodis (Baylis, 1929) n. comb. has previously been placed in the genus Spirocamallanus Olsen, 1952. However, this species shares the apomorphic presence of numerous mucrons on the female tail, and almost identical cephalic morphology, male caudal structures and female reproductive system with other procamallanines from clawed toads. This suggests that they represent a monophyletic grouping. There is also only limited morphometric differentiation between B. xenopodis and the other proposed representatives of Batrachocamallanus (supported by a multivariate analysis of male and female specimens), which further indicates a close relationship between them. Great variability in the presence and type of buccal capsule thickenings occurs within Batrachocamallanus. Members of this genus most closely resemble the African species Procamallanus laeviconchus (Wedl, 1862), which exhibits a smooth buccal capsule similar to that of B. siluranae. Buccal capsule thickenings of the remaining Batrachocamallanus spp. probably arose independently from those described in other procamallanines. Such characters may be evolutionarily unstable and an unsuitable basis for generic classification in this subfamily. Although B. siluranae is the only Batrachocamallanus species to occur in X. tropicalis-like hosts (which represent a separate lineage from other clawed toads), its distribution, and that of its congeners, may be determined more by host-independent ecological or biogeographical factors than by an association with host phylogeny. Thus, B siluranae occurs in Xenopus spp. from tropical rain forest (including those from other host lineages) while the other forms are typically found in savanna or montane forest, and in the cases of B. slomei and B. xenopodis at least, do not show narrow host specificity to particular clawed toad taxa. Although more than one Batrachocamallanus spp. were found in X. laevis, X. muelleri and X. fraseri-like clawed toads, co-existence at the same locality never occurred, perhaps indicating a high degree of interspecific ecological segregation.

Electronic Resource

1573-5192

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract The taxonomy, host range and geographical distribution ofOligolecithus Vercammen-Grandjean, 1960, a genus of telorchiid digeneans fromXenopus spp. in Africa, is reviewed.O. jonkershoekensis Pritchard, 1964 is established as a junior synonym ofO. elianae Vercammen-Grandjean, 1960, andO. siluranae n. sp. is described fromX. tropicalis in Ghana. These two species are differentiated by variations in body length, testicular arrangement and ventral sucker width in proportion to body size.O. elianae occurs inX. laevis laevis from South Africa and Zimbabwe (new locality record),X. l. poweri from Zaire,X. l. victorianus from Zaire, Uganda and Rwanda (new locality record),X. l. bunyoniensis (new host record) from Uganda andX. l. sudanensis from Sudan (new host and locality record). It is also found inX. wittei from Uganda and Zaire andX. vestitus (new host record) from Uganda. The host ofO. siluranae belongs to a separate species group within the genusXenopus from the hosts ofO. elianae; this “tropicalis” group is phylogenetically isolated, but it also occurs in a different biotype, lowland tropical rain forest, ecologically distinct from the other known host species.

Electronic Resource