Time for a plant structural economics spectrum

We argue that tree and crown structural diversity can and should be integrated in the whole-plant economics spectrum. Ecologists have found that certain functional trait combinations have been more viable than others during evolution, generating a trait trade-off continuum which can be summarized along a few axes of variation, such as the "worldwide leaf economics spectrum" and the "wood economics spectrum." However, for woody plants the crown structural diversity should be included as well in the recently introduced "global spectrum of plant form and function," which now merely focusses on plant height as structural factor. The recent revolution in terrestrial laser scanning (TLS) unlocks the possibility to describe the three dimensional structure of trees quantitatively with unprecedented detail. We demonstrate that based on TLS data, a multidimensional structural trait space can be constructed, which can be decomposed into a few descriptive axes or spectra. We conclude that the time has come to develop a "structural economics spectrum" for woody plants based on structural trait data across the globe. We make suggestions as to what structural features might lie on this spectrum and how these might help improve our understanding of tree form-function relationships

A computer simulation of a rail network

AbstractA computer simulation of a rail segment is presented. The goal is to provide a capability for scheduling and routing with respect to predetermined objectives. The simulation is founded on a decomposition of the given line segment into fundamental units representing node to node subsegments with each node being an interlocking of the real system. A decision subroutine is activated every time a train reaches a node; all feasible options are then examined with respect to the current configuration of the system. Ultimately, it is hoped the simulation will have on-line monitoring capabilities

Feasibility of Recommended Cognitive Screening Tools for Older Adults in Carehomes

No abstract available

Long term cognitive outcomes of early term (37-38 weeks) and late preterm (34-36 weeks) births: a systematic review

Background: There is a paucity of evidence regarding long-term outcomes of late preterm (34-36 weeks) and early term (37-38 weeks) delivery.  The objective of this systematic review was to assess long-term cognitive outcomes of children born at these gestations. Methods: Four electronic databases (Medline, Embase, clinicaltrials.gov and PsycINFO) were searched.  Last search was 5 th August 2016.  Studies were included if they reported gestational age, IQ measure and the ages assessed.  The protocol was registered with the International prospective register of systematic reviews (PROSPERO Record CRD42015015472).  Two independent reviewers assessed the studies.  Data were abstracted and critical appraisal performed of eligible papers. Results: Of 11,905 potential articles, seven studies reporting on 41,344 children were included.  For early term births, four studies (n = 35,711) consistently showed an increase in cognitive scores for infants born at full term (39-41 weeks) compared to those born at early term (37-38 weeks) with increases for each week of term (difference between 37 and 40 weeks of around 3 IQ points), despite differences in age of testing and method of IQ/cognitive testing.  Four studies (n = 5644) reporting childhood cognitive outcomes of late preterm births (34 - 36 weeks) also differed in study design (cohort and case control); age of testing; and method of IQ testing, and found no differences in outcomes between late preterm and term births, although risk of bias was high in included studies. Conclusion:  Children born at 39-41 weeks have higher cognitive outcome scores compared to those born at early term (37-38 weeks).  This should be considered when discussing timing of delivery.  For children born late preterm, the data is scarce and when compared to full term (37-42 weeks) did not show any difference in IQ scores

Homopolymer-rich regions in mammalian DNA

The presence of deoxyadenylate-rich (dA-rich) and deoxyguanylate-rich (dG-rich) regions in mammalian DNA has been demonstrated by hybridisation with [5H] poly(U) and [5H] poly(C). For BHK-21/CI3 cells, the maximum levels of these homopolymer-rich regions, as detected by the hybridisation technique, are about 0.41% of the DNA for dA-rich, and 0.1% of the DNA for dG-rich regions. Since the hybrids are largely sensitive to digestion with RNase, it is probable that the majority of hybrid molecules contain mismatched base-pairs. 0.13% of the DNA consists of dA-rich regions ranging in size from 25-130 nucleotides long and containing about 2-6% of bases other than adenine. On the other hand, dG-rich regions less than 40 nucleotides long comprise 0.07% of the DNA and contain 10-30% of bases other than guanine. Exhaustive RNase digestion of the hybrids enables detection of pure deoxyhomopolymeric regions in the DNA. Pure sequences of poly(dA) of average size about 31 nucleotides long account for 0.008% of BHK-21/C13 DNA, whereas poly(dG) sequences about 17 nucleotides long comprise 0.0016% of the-DNA. The organisation of these sequences within the genome has been investigated. Both dA-rich and dG-rich regions are present within DNA sequences of widely varying base composition. Extensive shearing of the DNA is required to produce some enrichment for dA-rich sequences in the A + T rich fraction, although dG-rich sequences are slightly enriched in the (3- + C rich fraction of even unsheared DNA. The buoyant density of hybrid molecules was found to be significantly greater than that of the unhybridised DNA only when highly sheared. DNA was used. Furthermore, dA- rich and dG-rich regions were shown to be associated with rapidly, intermediately, and slowly renaturing DNA sequences. These findings all suggest that the dA-rich and dA-rich regions have a widespread distribution throughout DNA molecules. The pure poly(dA) and poly(dG) sequences also appear to be scattered throughout DNA molecules. In situ hybridisation studies with C5H] poly(U) further suggest that the dA~rich regions are not localised to any particular chromosome or to any specific region of the chromosomes. Analysis of DNA from a number of different species has shown that, in general, the dA-rich and dG-rich regions are present to a much higher level in mammalian DNA than in bacterial, bacteriophage, and mammalian viral DNAs. Evidence for the existence of A-rich, U-rich and G-rich RNA species in BHK-21/015 cells has also been obtained. The characteristics of the homopolymer-rich regions in DNA suggest that the dA-rich and pure poly(dA) sequences are more likely to have a significant role than dG-rich and poly(dG) sequences. The possible functions of these unusual deoxynucleotide sequences are reviewed