Utility of Geochemical Analysis of Trace Fossils: Case Studies Using Phycosiphon incertum from the Lower Jurassic Shallow-Marine (Higashinagano Formation,Southwest Japan) and Pliocene Deep-Marine Deposits (Shiramazu Formation,Central Japan)

Elemental and mineralogical analyses of Phycosiphon incertum from the Lower Jurassic Higashinagano Formation and Pliocene Shiramazu Formation revealed that the core and mantle have significantly different compositions; the Al₂O₃/SiO₂ ratio, a general proxy for phyllosilicates to tectosilicates, showed a significantly (P < 0.01) higher value in the core than in the mantle. The obtained data strongly suggest that clay minerals are certainly concentrated in the core while coarse grains (i.e., quartz, feldspar) are enriched in the mantle. This is in agreement with the commonly believed interpretation of the Phycosiphon-producer; namely, it selectively ingested and excreted the clay-sized sediment grains and sorted out coarse grains. Difference in the degree of particle selection was also recognized; the tracemaker of the Higashinagano P. incertum showed greater degree of selectivity. This may be due to the differences in optimal foraging deposit-feeding activities affected by clay mineralogy of the host sediments, or in mechanistic consequences of particle selection induced by organic matter content, or in the number of other ichnotaxa recognized from each formation.     

Amino acid sequencing by gas chromatography-mass spectrometry using trifluoro-dideuteroalkylated peptide derivatives: C. The primary structure of the carboxypeptidase inhibitor from potatoes

The carboxypeptidase inhibitor from potatoes has been used to demonstrate the utility of gas chromatography-mass spectrometry for the determination of the primary structure of such large polypeptides. Two mixtures of oligopeptide fragments, obtained by limited acid hydrolysis and enzymatic digestion of this polypeptide, were transformed into the corresponding mixtures of O-trimethyl-silylated trifluoro-dideuteroethyl polyamino alcohols which were then analyzed by gas chromatography-mass spectrometry. The resulting mass spectral and retention index data allowed the identification of 61 oligopeptide fragments which were assembled by the computer by positioning all 39 amino acid residues in a unique sequence (with the exception of the assignment of the primary amide groups of Asn and Gln).     

Cortical arousal and social intimacy in the human female under different conditions of eye contact

The EEG was monitored from pairs of female subjects while they engaged in varied eye contact under experimenter instruction (direct gaze, smile, averted gaze). The nine conditions of gaze were related monotonically to EEG abundance (9.5–20.0 Hz). It is suggested that the gradient of arousal or activation so obtained is evidence of a physiological substrate of social intimacy.     

Growth and development of root systems of winter cereals grown after different tillage methods including direct drilling

Summary A method is described for rapidly estimating the depth of penetration and density of roots of cereal crops under field conditions. Counts of living roots, traversing horizontal faces of soil cores, were made for winter wheat growing on direct-drilled and ploughed land.The rate of penetration of roots of winter wheat in a clay and a sandy loam soil averaged 5 mm per day throughout winters without extremes of cold or wet. Death of roots near the soil surface occurred wilst others continued downward penetration. The rate of root elongation was slower during prolonged periods when the soil was wet and faster,i.e. to greater depths, during dry conditions.Damage sustained to roots during adverse winter conditions ofter varied between direct drilling and ploughing. More roots at depth were consistently recorded on direct-drilled than on ploughed land when measured in spring after a soil water deficit had developed during the preceding month. After prolonged wet soil conditions during the winter on a soil with a large clay fraction and low hydraulic conductivity, root growth and penetration in spring, before the development of a soil water deficit, was more restricted on direct-drilled than on ploughed land.     

Plant traits enabling survival in Mediterranean badlands in northeastern Spain suffering from soil erosion

Question: This study analysed the effect of severe soil erosion on species composition of plant communities by favouring species showing certain growth forms, root‐sprouting and clonal growth abilities. Location: The study area was located between the middle Ebro Valley and the Pre‐Pyrenees (northeastern Spain). Methods: Root‐sprouting and shoot‐rooting abilities, clonal reproduction and growth form were assessed for the 123 most common plant species from eroded lands in the study area. We obtained 260 vegetation relevés in three different substrata (gypsum outcrops, Miocene clays and Eocene marls) on areas with different degrees of soil erosion. The frequency of every plant trait in each relevé was estimated according to species presence. The effect of soil erosion on the frequency of plant attributes was assessed by correlation analyses. Results: Bipolar, non‐clonal plants and annual species decreased their frequency with increasing soil erosion in the three substrata analyzed, whereas root‐sprouters and woody plants (mostly sub‐shrubs) increased their frequency in most of the substrata analysed. Conclusions: Woody sub‐shrubs, root‐sprouters and clonal species are favoured in eroded lands in NE Spain. Bipolar species and annual plants might not be plastic enough to survive the high stress and frequent disturbances prevailing in such eroded areas.