Background complexity can mitigate poor camouflage

Avoiding detection through camouflage is often key to survival. However, an animal's appearance is not the only factor affecting conspicuousness: background complexity also alters detectability. This has been experimentally demonstrated for both artificially patterned backgrounds in the lab and natural backgrounds in the wild, but only for targets that already match the background well. Do habitats of high visual complexity provide concealment to even relatively poorly-camouflaged animals? Using artificial prey which differed in their degrees of background matching to tree bark, we were able to determine their survival, under bird predation, with respect to the natural complexity of the background. The latter was quantified using low-level vision metrics of feature congestion (or 'visual clutter') adapted for bird vision. Higher background orientation clutter (edges with varying orientation) reduced the detectability of all but the poorest background-matching camouflaged treatments; higher background luminance clutter (varying achromatic lightness) reduced average mortality for all treatments. Our results suggest that poorer camouflage can be mitigated by more complex backgrounds, with implications for both camouflage evolution and habitat preferences.Data file is: Rowe_at_al_data.txt Format: tab-delimited text Created: 24/03/2021 Description of variables (columns) Block "Experimental block (different part of study site on different dates): factor with 27 levels, 1 to 27." Treatment "Experimental treatment (varied average luminance): factor with 9 levels (1 = darkest, 9 = lightest)." Replicate "Replicate number, factor with 10 levels, nested within Block and Treatment." Censored "Binary code: 1 = bird predation, 0 = disappearance for any other reason (e.g. invertebrate predation) or survival to the end of the trial." Day "Day of disappearance: numeric, taking values 0 to 5. 0 indicates the replicate was lost before deployment (n=3)." Notes Plain text description of fate of target. contrast.fc Luminance contrast metric of feature congestion. colour.fc Colour contrast metric of feature congestion. orientation.fc Edge orientation metric of feature congestion. Funding provided by: Biotechnology & Biological Sciences Research Council, UKCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100000268Award Number: BB/S00873X/

Exploring the experience of sleep and fatigue in male and female adults over the 2 years following traumatic brain injury: a qualitative descriptive study

To explore the experience of fatigue and sleep difficulties over the first 2 years after traumatic brain injury (TBI). Longitudinal qualitative descriptive analysis of interviews completed as part of a larger longitudinal study of recovery following TBI. Data relating to the experience of fatigue and/or sleep were extracted and coded by two independent researchers. Community-based study in the Hamilton and Auckland regions of New Zealand. 30 adult participants who had experienced mild, moderate or severe brain injury within the past 6 months (>16 years of age). 15 participants also nominated significant others to take part. Interviews were completed at 6, 12 and 24 months postinjury. Participants described feeling unprepared for the intensity, impact and persistent nature of fatigue and sleep difficulties after injury. They struggled to learn how to manage their difficulties by themselves and to adapt strategies in response to changing circumstances over time. Four themes were identified: (1) Making sense of fatigue and sleep after TBI; (2) accepting the need for rest; (3) learning how to rest and; (4) need for rest impacts on ability to engage in life. Targeted support to understand, accept and manage the sleep and fatigue difficulties experienced may be crucial to improve recovery and facilitate engagement in everyday life. Advice needs to be timely and revised for relevance over the course of recovery

Judicious heteroatom doping produces high performance deep blue/near UV multiresonant thermally activated delayed fluorescence OLEDs

Funding: Horizon 2020 Framework Programme - 838885; Leverhulme Trust - RPG-2016-047; Engineering and Physical Sciences Research Council - EP/L017008, EP/P010482/1; Fonds de la Recherche Scientifiques de Belgique - 2.5020.11; Walloon Region - n1117545; Fonds De La Recherche Scientifique - FNRS - F.4534.21.Two multiresonant thermally activated delayed fluorescence (MR-TADF) emitters are presented and it is shown how further borylation of a deep-blue MR-TADF emitter, DIDOBNA-N, both blueshifts and narrows the emission producing a new near-UV MR-TADF emitter, MesB-DIDOBNA-N, are shown. DIDOBNA-N emits bright blue light (ΦPL = 444 nm, FWHM = 64 nm, ΦPL = 81%, τd = 23 ms, 1.5 wt% in TSPO1). The deep-blue organic light-emitting diode (OLED) based on this twisted MR-TADF compound shows a very high maximum external quantum efficiency (EQEmax) of 15.3% for a device with CIEy of 0.073. The fused planar MR-TADF emitter, MesB-DIDOBNA-N shows efficient and narrowband near-UV emission (λPL = 402 nm, FWHM = 19 nm, ΦPL = 74.7%, τd = 133 ms, 1.5 wt% in TSPO1). The best OLED with MesB-DIDOBNA-N, doped in a co-host, shows the highest efficiency reported for a near-UV OLED at 16.2%. With a CIEy coordinate of 0.049, this device also shows the bluest EL reported for a MR-TADF OLED to date.Publisher PDFPeer reviewe

The Transit Ingress and the Tilted Orbit of the Extraordinarily Eccentric Exoplanet HD 80606b

We present the results of a transcontinental campaign to observe the 2009 June 5 transit of the exoplanet HD 80606b. We report the first detection of the transit ingress, revealing the transit duration to be 11.64 +/- 0.25 hr and allowing more robust determinations of the system parameters. Keck spectra obtained at midtransit exhibit an anomalous blueshift, giving definitive evidence that the stellar spin axis and planetary orbital axis are misaligned. The Keck data show that the projected spin-orbit angle is between 32-87 deg with 68.3% confidence and between 14-142 deg with 99.73% confidence. Thus the orbit of this planet is not only highly eccentric (e=0.93), but is also tilted away from the equatorial plane of its parent star. A large tilt had been predicted, based on the idea that the planet's eccentric orbit was caused by the Kozai mechanism. Independently of the theory, it is noteworthy that all 3 exoplanetary systems with known spin-orbit misalignments have massive planets on eccentric orbits, suggesting that those systems migrate differently than lower-mass planets on circular orbits.Comment: ApJ, in press [13 pg

Genome-wide analyses implicate 33 loci in heritable dog osteosarcoma, including regulatory variants near CDKN2A/B

Background: Canine osteosarcoma is clinically nearly identical to the human disease, but is common and highly heritable, making genetic dissection feasible. Results: Through genome-wide association analyses in three breeds (greyhounds, Rottweilers, and Irish wolfhounds), we identify 33 inherited risk loci explaining 55% to 85% of phenotype variance in each breed. The greyhound locus exhibiting the strongest association, located 150 kilobases upstream of the genes CDKN2A/B, is also the most rearranged locus in canine osteosarcoma tumors. The top germline candidate variant is found at a >90% frequency in Rottweilers and Irish wolfhounds, and alters an evolutionarily constrained element that we show has strong enhancer activity in human osteosarcoma cells. In all three breeds, osteosarcoma-associated loci and regions of reduced heterozygosity are enriched for genes in pathways connected to bone differentiation and growth. Several pathways, including one of genes regulated by miR124, are also enriched for somatic copy-number changes in tumors. Conclusions: Mapping a complex cancer in multiple dog breeds reveals a polygenic spectrum of germline risk factors pointing to specific pathways as drivers of disease

Survey of Period Variations of Superhumps in SU UMa-Type Dwarf Novae

We systematically surveyed period variations of superhumps in SU UMa-type dwarf novae based on newly obtained data and past publications. In many systems, the evolution of superhump period are found to be composed of three distinct stages: early evolutionary stage with a longer superhump period, middle stage with systematically varying periods, final stage with a shorter, stable superhump period. During the middle stage, many systems with superhump periods less than 0.08 d show positive period derivatives. Contrary to the earlier claim, we found no clear evidence for variation of period derivatives between superoutburst of the same object. We present an interpretation that the lengthening of the superhump period is a result of outward propagation of the eccentricity wave and is limited by the radius near the tidal truncation. We interpret that late stage superhumps are rejuvenized excitation of 3:1 resonance when the superhumps in the outer disk is effectively quenched. Many of WZ Sge-type dwarf novae showed long-enduring superhumps during the post-superoutburst stage having periods longer than those during the main superoutburst. The period derivatives in WZ Sge-type dwarf novae are found to be strongly correlated with the fractional superhump excess, or consequently, mass ratio. WZ Sge-type dwarf novae with a long-lasting rebrightening or with multiple rebrightenings tend to have smaller period derivatives and are excellent candidate for the systems around or after the period minimum of evolution of cataclysmic variables (abridged).Comment: 239 pages, 225 figures, PASJ accepte

Kinematics of experimentally produced deformation bands in stibnite

Using videotape techniques, we have observed the kinematic development of a variety of microstructures during experimental deformation of single crystals of stibnite (Sb2S3). The crystals were deformed by flexure or uniaxial compression at room P-T conditions in a small strain device attached to the stage of a reflecting microscope. In more than 50 experimental runs, the primary microstructures produced in stibnite were deformation bands, not deformation twins as often reported in the literature. Translation gliding along (010) [001] results in visible slipbands and produces two basic types of deformation bands, each with a variety of subtypes. Kink bands form with [phi] (angle of internal rotation) [approximate, equal]70[deg] and perpendicular bands develop with [phi][approximate, equal] 90[deg]. Other optical deformation features seen forming were: breccia fragments, bent and opened cleavages, and microfolds.Four stages could be seen in the kinematic development of deformation bands. During initiation, bands form by nearly instantaneous propagation of a narrow bent zone across the crystal. During later migration, the bands widen at a rate invariably slower than the rate of initiation. Termination of bands occurs when growth is impeded by intersections with grain boundaries or other deformation features. During late modification, previously formed bands with straight boundaries are sheared, bent, and compressed. Unconfined crystals tend to form kinks, whereas the perpendicular bands formed in samples confined in relatively rigid plastic. Naturally deformed stibnites show the same features. Television photomicroscopy has great potential for studying microstructures during deformation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23215/1/0000144.pd