A combinatorial approach to angiosperm pollen morphology

Angiosperms (flowering plants) are strikingly diverse. This is clearly expressed in the morphology of their pollen grains, which are characterized by enormous variety in their shape and patterning. In this paper, I approach angiosperm pollen morphology from the perspective of enumerative combinatorics. This involves generating angiosperm pollen morphotypes by algorithmically combining character states and enumerating the results of these combinations. I use this approach to generate 3 643 200 pollen morphotypes, which I visualize using a parallel-coordinates plot. This represents a raw morphospace. To compare real-world and theoretical morphologies, I map the pollen of 1008 species of Neotropical angiosperms growing on Barro Colorado Island (BCI), Panama, onto this raw morphospace. This highlights that, in addition to their well-documented taxonomic diversity, Neotropical rainforests also represent an enormous reservoir of morphological diversity. Angiosperm pollen morphospace at BCI has been filled mostly by pollen morphotypes that are unique to single plant species. Repetition of pollen morphotypes among higher taxa at BCI reflects both constraint and convergence. This combinatorial approach to morphology addresses the complexity that results from large numbers of discrete character combinations and could be employed in any situation where organismal form can be captured by discrete morphological characters

Factors influencing the implementation of Global Polio Eradication Initiative in low- and middle-income countries : a qualitative evidence synthesis

Background The World Health Organization’s Global Polio Eradication Initiative (GPEI) has succeeded in reducing the cases of Polio by 99%. The persistence of the remaining 1% in Pakistan, Afghanistan and Nigeria has continued to pose threats to polio-free neighbouring countries. This systematic review aims to contribute to ongoing efforts to eradicate polio by exploring factors that influence the successful implementation of the GPEI in low- and middle-income countries. Methods We reviewed qualitative research or mixed methods study reports published between 2012-2018 from studies conducted in low- and middle-income countries. We extracted qualitative research data using a standardised data extraction form and assessed study quality using the Critical Appraisal Skills Programme (CASP) qualitative checklist. We then conducted best-fit framework synthesis to organise, and explore patterns in, the data relating to new and existing themes. We report data on factors influencing the implementation of polio eradication efforts organised by theme. Results We included 11 studies published between 2012 and 2017. Most of the studies were conducted in Pakistan and Nigeria with other countries (Ethiopia, Cameroon, Angola) also represented. The ten themes included structural factors (the development of capacity, through infrastructure and training) and attitudinal factors (including cultural and religious beliefs), were particularly important given the characteristics of included low- and middle-income countries. Common factors emerged across the included studies and generally these mapped well to the underpinning “best fit” framework. Conclusions This qualitative evidence synthesis offers a useful expanded framework by which policymakers can explore factors specific to their geographical and population-based context although it should be recognised that individual factors relating to personal values and belief systems may moderate any community response to a polio vaccination programme

Ligand binding to a hemoprotein lacking the distal histidine. The myoglobin from aplysia limacina (Val(E7)).

The time course of ligand recombination to the myoglobin from Aplysia limacina, which has Val(E7), was measured following photolysis by flashes of 35 ps to 300 ns with a time resolution of 10 ps or 1 ns. CO shows only biomolecular recombination. O2 has a small geminate reaction with a half-time of tens of picoseconds, but no nanosecond geminate reaction. NO has two picosecond relaxations with half-times of 70 ps (15%) and 1 ns (80%) and one nanosecond relaxation with a half-time of 4.6 ns. The biomolecular rates for O2 and NO are the same: 2 x 10(7) M-1 s-1. Methyl and ethyl isonitriles have a geminate reaction with a half-time of 35 ps. Ethyl isonitrile has, in addition, a nanosecond relaxation (25%) with a half-time of 100 ns. t-Butyl isonitrile has four geminate relaxations (10 ps, 35 ps, 1 ns, and 1 microseconds). Analysis of the results suggests much easier movement of ligand between the heme pocket and the exterior than in sperm whale myoglobin (His(E7]. The reactivity of the heme is little different, placing the effect of the differences from sperm whale myoglobin on the distal side of the heme

Variation for potassium and sodium accumulation in a family from a cross between grapevine rootstocks K 51-40 and 140 Ruggeri

The variation in potassium (K+) and sodium (Na+) accumulation was investigated between 60 hybrids within a family obtained by crossing grapevine rootstocks K 51-40 (Vitis champinii 'Dogridge' × V. riparia 'Gloire', seed parent) with 140 Ruggeri (V. cinerea var. helleri 'Resseguier #2' × V. rupestris'St. George', pollen parent), which are known to result in higher and lower concentrations of K+, respectively, but similar concentrations of Na+, in grape juice and resultant wine from scions grafted to them. The hybrids, their parents and two standard rootstocks, Ramsey (V. champinii 'Ramsey') and 1103 Paulsen (V. cinerea var. helleri 'Resseguier #2' x V. rupestris'St. George') were replicated by clonal propagation and grown under glasshouse conditions either in potting mix, drip-irrigated with a nutrient solution containing 50, 1.7 and 30 mM Cl-, K+ and Na+, respectively, or in aerated nutrient solution containing 25, 1.7 and 15 mM Cl-, K+ and Na+, respectively. In both pot and solution culture trials, there were significant (P < 0.001) differences between parents for mean K+ (but not Na+) concentrations, and between hybrids for mean K+ and Na+ concentrations in laminae. This variation between the hybrids was continuous, indicating multiple rather than single gene control for K+ and Na+ accumulation within the family. Differences among the hybrids for lamina K+ accumulation were not strongly associated with plant vigour. While the ranking of some hybrids for K+ and Na+ accumulation was consistent between the trials, others responded differently, suggesting the environment of the rootzone may affect the K+ and Na+ accumulation phenotype.

The integrability of Lie-invariant geometric objects generated by ideals in the Grassmann algebra

We investigate closed ideals in the Grassmann algebra serving as bases of Lie-invariant geometric objects studied before by E. Cartan. Especially, the E. Cartan theory is enlarged for Lax integrable nonlinear dynamical systems to be treated in the frame work of the Wahlquist Estabrook prolongation structures on jet-manifolds and Cartan-Ehresmann connection theory on fibered spaces. General structure of integrable one-forms augmenting the two-forms associated with a closed ideal in the Grassmann algebra is studied in great detail. An effective Maurer-Cartan one-forms construction is suggested that is very useful for applications. As an example of application the developed Lie-invariant geometric object theory for the Burgers nonlinear dynamical system is considered having given rise to finding an explicit form of the associated Lax type representation

Progesterone and 17 α-Hydroxyprogesterone: Novel Stimulators of Calcium Influx in Human Sperm

Progesterone and 17 alpha-hydroxyprogesterone (but not other steroids such as testosterone, corticosterone, beta-estradiol, estrone, dehydroepiandrosterone, 20 alpha-hydroxypregnen-3-one, androstenedione, and pregnenolone) were shown to cause an immediate increase, in free cytosolic calcium ([Ca2+]i) in both capacitated and noncapacitated human sperm, using the fluorescent indicator fura 2. Significant increases in [Ca2+]i were observed with 10 ng/ml progesterone, while maximum effects were seen with 1 microgram/ml progesterone. Two other steroids 11 beta-hydroxyprogesterone and 5 alpha-pregnane-3,20-dione exhibited significant activity to increase [Ca2+]i. This increase in [Ca2+]i elicited by progesterone was entirely due to Ca2+ influx from the extracellular medium since the increase in [Ca2+]i was blocked by the Ca2+ chelator EGTA (2.5 mM) and the Ca2+ channel antagonist La3+ (0.25 mM) when added to the medium containing 2.5 mM Ca2+. Progesterone also stimulated the uptake of Mn2+ into sperm as measured by the quenching of fura 2 fluorescence. Progesterone has been found in human follicular fluid at levels capable of stimulating increases in [Ca2+]i. The similarities in responses induced by human follicular fluid and progesterone an increase in [Ca2+]i, and hence the acrosome reaction, is progesterone and/or 17 alpha-hydroxyprogesterone. Progesterone (1 microgram/ml) did not increase [Ca2+]i in somatic cells such as adipocytes, hepatocytes, Balb/c 3T3 cells, normal rat kidney, or DDT1 MF-2 cells. The effects of these progestins to increase [Ca2+]i, by activating a receptor-operated calcium channel, is the first report of such an activity in sperm. This phenomena possibly opens up a new field of steroid action in the area of sterility, fertility, and contraception at the level of the sperm

A Memetic Analysis of a Phrase by Beethoven: Calvinian Perspectives on Similarity and Lexicon-Abstraction

This article discusses some general issues arising from the study of similarity in music, both human-conducted and computer-aided, and then progresses to a consideration of similarity relationships between patterns in a phrase by Beethoven, from the first movement of the Piano Sonata in A flat major op. 110 (1821), and various potential memetic precursors. This analysis is followed by a consideration of how the kinds of similarity identified in the Beethoven phrase might be understood in psychological/conceptual and then neurobiological terms, the latter by means of William Calvin’s Hexagonal Cloning Theory. This theory offers a mechanism for the operation of David Cope’s concept of the lexicon, conceived here as a museme allele-class. I conclude by attempting to correlate and map the various spaces within which memetic replication occurs

Two Optimal One-Error-Correcting Codes of Length 13 That Are Not Doubly Shortened Perfect Codes

The doubly shortened perfect codes of length 13 are classified utilizing the classification of perfect codes in [P.R.J. \"Osterg{\aa}rd and O. Pottonen, The perfect binary one-error-correcting codes of length 15: Part I - Classification, IEEE Trans. Inform. Theory, to appear]; there are 117821 such (13,512,3) codes. By applying a switching operation to those codes, two more (13,512,3) codes are obtained, which are then not doubly shortened perfect codes.Comment: v2: a correction concerning shortened codes of length 1