Substantial variation in leaf senescence times among 1360 temperate woody plant species: implications for phenology and ecosystem processes

Background and Aims Autumn leaf senescence marks the end of the growing season in temperate ecosystems. Its timing influences a number of ecosystem processes, including carbon, water and nutrient cycling. Climate change is altering leaf senescence phenology and, as those changes continue, it will affect individual woody plants, species and ecosystems. In contrast to spring leaf out times, however, leaf senescence times remain relatively understudied. Variation in the phenology of leaf senescence among species and locations is still poorly understood.Methods Leaf senescence phenology of 1360 deciduous plant species at six temperate botanical gardens in Asia, North America and Europe was recorded in 2012 and 2013. This large data set was used to explore ecological and phylogenetic factors associated with variation in leaf senescence.Key Results Leaf senescence dates among species varied by 3 months on average across the six locations. Plant species tended to undergo leaf senescence in the same order in the autumns of both years at each location, but the order of senescence was only weakly correlated across sites. Leaf senescence times were not related to spring leaf out times, were not evolutionarily conserved and were only minimally influenced by growth habit, wood anatomy and percentage colour change or leaf drop. These weak patterns of leaf senescence timing contrast with much stronger leaf out patterns from a previous study.Conclusions The results suggest that, in contrast to the broader temperature effects that determine leaf out times, leaf senescence times are probably determined by a larger or different suite of local environmental effects, including temperature, soil moisture, frost and wind. Determining the importance of these factors for a wide range of species represents the next challenge for understanding how climate change is affecting the end of the growing season and associated ecosystem processes.     

Role of nucleoside transport in glucocorticoid-induced regression of mouse lymphoma P1798

Exposure of corticoid-sensitive P1798 lymphocytes to cortisol results in inhibition of uridine uptake and incorporation with no effect on 2-deoxyglucose transport. Nucleoside uptake by corticoid-resistant cells is not affected by the hormone. Inhibition of uridine transport may play a key role in tumor regression and does not depend on reduced availability of glucose.     

Impact of community-orientated psychiatry on marriage and fertility of psychotic women

A large representative sample of psychotic women of reproductive age was selected from patients admitted to a London mental hospital during 1955–63 and followed up during the years of developing community care. Before first admission the probability of marriage of schizophrenics was three-quarters of that of corresponding normal women, and after admission it was just over one-third of normal. Fertility of schizophrenics was slightly reduced both before and after illness, and much of this reduction remains due to their being in hospital. The probability of marriage and fertility of women suffering from severe affective disorders was very similar to that found in the corresponding general population. Despite a lessening of differentials between patients and normal women since the impact of community care the probability of marriage of schizophrenics with abnormal personalities is still significantly reduced.     

DUODENAL ULCER—Rationale and Results of Antrectomy and Subtotal Vagotomy

Results in a series of 107 cases indicated that antrectomy (hemigastrectomy) combined with subtotal vagotomy of both vagus nerves for duodenal ulcer is followed by better overall results than the more radical subtotal gastrectomy or vagotomy plus drainage procedures.Antrectomy combined with total vagotomy is followed by a slightly smaller incidence of marginal ulcer but is accompanied by more motility disturbances.