Blue, white, and red ocean planets - Simulations of orbital variations in flux and polarization colors

An exoplanet's habitability will depend strongly on the presence of liquid water. Flux and/or polarization measurements of starlight that is reflected by exoplanets could help to identify exo-oceans. We investigate which broadband spectral features in flux and polarization phase functions of reflected starlight uniquely identify exo-oceans. We compute total fluxes F and polarized fluxes Q of starlight reflected by cloud-free and (partly) cloudy exoplanets, for wavelengths from 350 to 865 nm. The ocean surface has waves composed of Fresnel reflecting wave facets and whitecaps, and scattering within the water body is included. Total flux F, polarized flux Q, and degree of polarization P of ocean planets change color from blue, through white, to red at phase angles alpha ranging from 134-108 deg for F, and from 123-157 deg for Q, with cloud coverage fraction fc increasing from 0.0 to 1.0 for F, and to 0.98 for Q. The color change in P only occurs for fc ranging from 0.03-0.98, with the color crossing angle alpha ranging from 88-161 deg. The total flux F of a cloudy, zero surface albedo planet can also change color, and for fc=0.0, an ocean planet's F will not change color for surface pressures ps > 8 bars. Polarized flux Q of a zero surface albedo planet does not change color for any fc. The color change of P of starlight reflected by an exoplanet, from blue, through white, to red with increasing alpha above 88 deg, appears to identify a (partly) cloudy exo-ocean. The color change of polarized flux Q with increasing alpha above 123 deg appears to uniquely identify an exo-ocean, independent of surface pressure or cloud fraction. At the color changing phase angle, the angular distance between a star and its planet is much larger than at the phase angle where the glint appears in reflected light. The color change in polarization thus offers better prospects for detecting exo-oceans.Comment: Accepted for publication in Astron. Astrophys; multicolumn versio

CGIAR Research Program on Forests, Trees and Agroforestry - Plan of Work and Budget 2020

There were no significant changes in 2019 to FTA’s theory of change1. FTA plans all its work on the basis of its operational priorities. These, in turn, focusresearch towards major development demands and knowledge gaps, orienting FTA towards the implementation of the SDGs and other global commitments. Three operational priorities were added in 2020 (see list in Appendix 1) to better delineate pre-existing research areas addressing development bottlenecks needing dedicated investment and visibility: smallholder tree-crop commodities, tree seeds and seedlings delivery systems, and foresight. FTA organized in 2019, at the request of its ISC, a joint ISC-FTA workshop on impact assessment methods for the program. Based on the outcomes of this workshop FTA will, inter alia, revisit in 2020 its impact pathways and end of programme outcomes, and if need be, corresponding adjustments to the ToC of FTA and/or of its FPs will be made

Biooptical variability in the Greenland Sea observed with the Multispectral Airborne Radiometer System (MARS)

A site-specific ocean color remote sensing algorithm was developed and used to convert Multispectral Airborne Radiometer System (MARS) spectral radiance measurements to chlorophyll-a concentration profiles along aircraft tracklines in the Greenland Sea. The analysis is described and the results given in graphical or tabular form. Section 2 describes the salient characteristics and history of development of the MARS instrument. Section 3 describes the analyses of MARS flight segments over consolidated sea ice, resulting in a set of altitude dependent ratios used (over water) to estimate radiance reflected by the surface and atmosphere from total radiance measured. Section 4 presents optically weighted pigment concentrations calculated from profile data, and spectral reflectances measured in situ from the top meter of the water column; this data was analyzed to develop an algorithm relating chlorophyll-a concentrations to the ratio of radiance reflectances at 441 and 550 nm (with a selection of coefficients dependent upon whether significant gelvin presence is implied by a low ratio of reflectances at 410 and 550 nm). Section 5 describes the scaling adjustments which were derived to reconcile the MARS upwelled radiance ratios at 410:550 nm and 441:550 nm to in situ reflectance ratios measured simultaneously on the surface. Section 6 graphically presents the locations of MARS data tracklines and positions of the surface monitoring R/V. Section 7 presents stick-plots of MARS tracklines selected to illustrate two-dimensional spatial variability within the box covered by each day's flight. Section 8 presents curves of chlorophyll-a concentration profiles derived from MARS data along survey tracklines. Significant results are summarized in Section 1

CGIAR Research Program on Forests, Trees and Agroforestry - Plan of Work and Budget 2020

There were no significant changes in 2019 to FTA’s theory of change1. FTA plans all its work on the basis of its operational priorities. These, in turn, focusresearch towards major development demands and knowledge gaps, orienting FTA towards the implementation of the SDGs and other global commitments. Three operational priorities were added in 2020 (see list in Appendix 1) to better delineate pre-existing research areas addressing development bottlenecks needing dedicated investment and visibility: smallholder tree-crop commodities, tree seeds and seedlings delivery systems, and foresight. FTA organized in 2019, at the request of its ISC, a joint ISC-FTA workshop on impact assessment methods for the program. Based on the outcomes of this workshop FTA will, inter alia, revisit in 2020 its impact pathways and end of programme outcomes, and if need be, corresponding adjustments to the ToC of FTA and/or of its FPs will be made

Synchronization in disordered Josephson junction arrays: Small-world connections and the Kuramoto model

We study synchronization in disordered arrays of Josephson junctions. In the first half of the paper, we consider the relation between the coupled resistively- and capacitively shunted junction (RCSJ) equations for such arrays and effective phase models of the Winfree type. We describe a multiple-time scale analysis of the RCSJ equations for a ladder array of junctions \textit{with non-negligible capacitance} in which we arrive at a second order phase model that captures well the synchronization physics of the RCSJ equations for that geometry. In the second half of the paper, motivated by recent work on small world networks, we study the effect on synchronization of random, long-range connections between pairs of junctions. We consider the effects of such shortcuts on ladder arrays, finding that the shortcuts make it easier for the array of junctions in the nonzero voltage state to synchronize. In 2D arrays we find that the additional shortcut junctions are only marginally effective at inducing synchronization of the active junctions. The differences in the effects of shortcut junctions in 1D and 2D can be partly understood in terms of an effective phase model.Comment: 31 pages, 21 figure

Fast nuclear staining of head hair roots as a screening method for successful STR analysis in forensics

The success rate of STR profiling of hairs found at a crime scene is quite low and negative results of hair analysis are frequently reported. To increase the success rate of DNA analysis of hairs in forensics, nuclei in hair roots can be counted after staining the hair root with DAPI. Two staining methods were tested: a longer method with two 1 h incubations in respectively a DAPI-and a wash-solution, and a fast, direct staining of the hair root on microscope slides. The two staining methods were not significantly different. The results of the STR analysis for both procedures showed that 20 nuclei are necessary to obtain at least partial STR profiles. When more than 50 nuclei were counted, full STR profiles were always obtained. In 96% of the cases where no nuclei were detected, no STR profile could be obtained. However, 4% of the DAPI-negative hair roots resulted in at least partial STR profiles. Therefore, each forensic case has to be evaluated separately in function of the importance of the evidential value of the found hair. The fast staining method was applied in 36 forensic cases on 279 hairs in total. A fast screening method using DAPI can be used to increase the success rate of hair analysis in forensics

Death as a threshold: Being with a person as they are dying

In The Art of Living and Dying, Osho writes that the West attempts to hide death. This is in spite of the increase in representations of death and dying in non-fiction and fiction writing, film and television entertainment, documentaries, news, sociology and psychology this century. There is however, limited writing about everyday, personal experiences of dying and death, perhaps because we find the personal too close to disclose, or language and grammar inadequate. This paper discusses aspects of what it means to be with, or alongside, someone who is dying from a personal perspective. It follows Kübler-Ross in suggesting that we need to speak and listen meaningfully about experiences of those who are dying and those with, or alongside, them. It draws on the experience of being with a friend and an uncle in the final weeks of their lives to suggest that society would benefit from confronting death productively, accepting that we all die and engaging positively in the process of dying with the person who is dying, those alongside them, family, friends and community. Writing and talking about death, requires taking account of bodies – those of the person who is dying, as well as those who are alongside them