Most massive stars end their lives as red supergiants (RSGs), a short-lived evolutionary phase when they are known to pulsate with varying amplitudes. The RSG period-luminosity (PL) relation has been ...measured in the Milky Way, the Magellanic Clouds and M33 for about 120 stars in total. Using over 1500 epochs of R-band monitoring from the Palomar Transient Factory survey over a five-year period, we study the variability of 255 spectroscopically cataloged RSGs in M31. We find that all RGSs brighter than MK −10 mag (log(L/L ) > 4.8) are variable at ΔmR > 0.05 mag. Our period analysis finds 63 with significant pulsation periods. Using the periods found and the known values of MK for these stars, we derive the RSG PL relation in M31 and show that it is consistent with those derived earlier in other galaxies of different metallicities. We also detect, for the first time, a sequence of likely first-overtone pulsations. Comparison to stellar evolution models from MESA confirms the first-overtone hypothesis and indicates that the variable stars in this sample have 12 M < M < 24 M . As these RSGs are the immediate progenitors to Type II-P core-collapse supernovae (SNe), we also explore the implication of their variability in the initial-mass estimates for SN progenitors based on archival images of the progenitors. We find that this effect is small compared to the present measurement errors.
A mild, iron-based catalyst system is presented that selectively oxidizes secondary alcohols to the corresponding hydroxy ketones in the presence of primary alcohols within 15 minutes at room ...temperature, utilizing H2O2 as the oxidant.
Patients with end-stage bladder disease can be treated with cystoplasty using gastrointestinal segments. The presence of such segments in the urinary tract has been associated with many ...complications. We explored an alternative approach using autologous engineered bladder tissues for reconstruction.
Seven patients with myelomeningocele, aged 4–19 years, with high-pressure or poorly compliant bladders, were identified as candidates for cystoplasty. A bladder biopsy was obtained from each patient. Urothelial and muscle cells were grown in culture, and seeded on a biodegradable bladder-shaped scaffold made of collagen, or a composite of collagen and polyglycolic acid. About 7 weeks after the biopsy, the autologous engineered bladder constructs were used for reconstruction and implanted either with or without an omental wrap. Serial urodynamics, cystograms, ultrasounds, bladder biopsies, and serum analyses were done.
Follow-up range was 22–61 months (mean 46 months). Post-operatively, the mean bladder leak point pressure decrease at capacity, and the volume and compliance increase was greatest in the composite engineered bladders with an omental wrap (56%, 1·58-fold, and 2·79-fold, respectively). Bowel function returned promptly after surgery. No metabolic consequences were noted, urinary calculi did not form, mucus production was normal, and renal function was preserved. The engineered bladder biopsies showed an adequate structural architecture and phenotype.
Engineered bladder tissues, created with autologous cells seeded on collagen-polyglycolic acid scaffolds, and wrapped in omentum after implantation, can be used in patients who need cystoplasty.
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DOBA, GEOZS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SIK, UILJ, UKNU, UL, UM, UPCLJ, UPUK, VSZLJ
The applicability of pressure-induced starch gelatinisation as a pressure time temperature indicator (PTTI) was investigated by examining the impact of pressure, temperature and treatment time on ...starches of A-type, B-type and C-type crystallinity. Pressure-induced starch gelatinisation was highly sensitive to changes of temperature, pressure and treatment time. At constant temperature and treatment time, the degree of gelatinisation increased with increasing pressure. The higher the temperature, the lower was the pressure of complete gelatinisation at the temperatures investigated. At constant temperature and pressure, the degree of gelatinisation increased with increasing treatment time. However, the degree of gelatinisation of potato starch suspensions remained unchanged after treatments above 60 min. The velocity rate of gelatinisation increased, the higher the constant pressure, indicating that pressure-induced gelatinisation is a time-dependant process. Hence, an application of starches as PTTIs seems possible. However, the starches have to be carefully selected regarding maximum gelatinisation at the temperature and treatment time applied in the high hydrostatic pressure process that reflects the pressure range desirable for processing.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We present the discovery of the second binary with a Roche lobe-filling hot subdwarf transferring mass to a white dwarf (WD) companion. This 56 minute binary was discovered using data from the Zwicky ...Transient Facility. Spectroscopic observations reveal an He-sdOB star with an effective temperature of Teff = 33,700 1000 K and a surface gravity of log(g) = 5.54 0.11. The GTC+HiPERCAM light curve is dominated by the ellipsoidal deformation of the He-sdOB star and shows an eclipse of the He-sdOB by an accretion disk as well as a weak eclipse of the WD. We infer a He-sdOB mass of MsdOB = 0.41 0.04 M and a WD mass of MWD = 0.68 0.05 M . The weak eclipses imply a WD blackbody temperature of 63,000 10,000 K and a radius RWD = 0.0148 0.0020 R as expected for a WD of such high temperature. The He-sdOB star is likely undergoing hydrogen shell burning and will continue transferring mass for 1 Myr at a rate of 10−9 M yr−1, which is consistent with the high WD temperature. The hot subdwarf will then turn into a WD and the system will merge in 30 Myr. We suggest that Galactic reddening could bias discoveries toward preferentially finding Roche lobe-filling systems during the short-lived shell-burning phase. Studies using reddening-corrected samples should reveal a large population of helium core-burning hot subdwarfs with Teff 25,000 K in binaries of 60-90 minutes with WDs. Though not yet in contact, these binaries would eventually come into contact through gravitational-wave emission and explode as a subluminous thermonuclear supernova or evolve into a massive single WD.
A manatee's primary modality to detect a vessel on a possible collision course is hearing as underwater visibility is limited in many manatee habitats and their visual acuity is poor. We estimate a ...Florida manatee's ability to detect the sound of an approaching boat and vocalizations in four different soundscapes in Sarasota Bay, FL. Background noise samples were collected every 5 minutes for a two-week period during winter and summer at each location (2019 or 2020). Sound levels in third octave bands (0.5, 1, 2, 4, and 8 kHz) were measured and compared to manatee auditory hearing thresholds and to sound levels of an approaching boat traveling at a slow, medium, or fast speed. Background sound levels in a wider band (1-20 kHz) were calculated to model vocal communication space at each location. We found that a manatee's estimated ability to detect an approaching boat differs greatly among locations, with time of day, and by season, and that fast boats are predicted to be detected later than slow boats. Latency of boat noise detection is estimated to sharply increase when considering unusually loud background noise levels. We suggest that such uncommonly loud conditions (e.g. 95th percentile sound level), not just typical conditions (median sound level), are important to consider for understanding the problem of manatee-boat collisions. Additionally, background noise impacts estimated vocal communication space and may limit the ability of vocal-mediated mother-calf cohesion. Altogether, a manatee's ability to detect acoustic signals of interest is expected to vary greatly spatially and temporally.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Social play involves a dynamic combination of competition and cooperation, yet few studies have systematically evaluated the cooperative side of play. We studied dyadic play in domestic dogs to ...investigate factors influencing variation in cooperative play strategies like self-handicapping and role reversal. Dyadic play bouts were videotaped and coded for asymmetric behaviours. We predicted that variation in play style would reflect salient aspects of the canine social system, including dominance relationships and age and size differences, but not sex differences. Our results refute the 50:50 rule proposed by some researchers, which asserts that participants must equalize their behaviour to maintain a playful atmosphere. We observed divergence from 50:50 symmetry to varying degrees across dyads. This variability was especially linked to dominance and age advantages, such that higher-ranking and/or older dogs generally showed higher proportions of attacks and pursuits and lower proportions of self-handicapping than their disadvantaged play partners. These results contradict the notion that more advantaged individuals consistently relinquish their advantage to facilitate play. Role reversals did occur, but certain social conventions apparently dictated which behaviours could be used during role reversals. For example, role reversals occurred during chases and tackles, but never during mounts, muzzle bites or muzzle licks, suggesting that these latter behaviours may be invariant indicators of formal dominance during play in domestic dogs. Play signalling was linked to self-handicapping behaviour but not to attack/pursuit behaviour, indicating that perhaps self-handicapping and play signalling work together to communicate playful intent and reinforce existing roles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Temporal and spatial changes in wind speed, wind direction, and moisture content are ubiquitous across sandy coastal beaches. Often these factors interact in unknown ways to create complexity that ...confounds our ability to model sediment transport at any point across the beach as well as our capacity to predict sediment delivery into the adjacent foredunes. This study was designed to measure wind flow and sediment transport over a beach and foredune at Greenwich Dunes, Prince Edward Island National Park, with the express purpose of addressing these complex interactions.
Detailed measurements are reported for one stormy day, October 11, 2004, during which meteorological conditions were highly variable. Wind speed ranged from 4 ms
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, wind direction was highly oblique varying between 60° and 85° from shore perpendicular, and moisture content of the sand surface ranged from a minimum of about 3% (by mass) to complete saturation depending on precipitation, tidal excursion, and storm surge that progressively inundated the beach. The data indicate that short-term variations (i.e., minutes to hours) in sediment transport across this beach arise predominantly because of short-term changes in wind speed, as is expected, but also because of variations in wind direction, precipitation intensity, and tide level. Even slight increases in wind speed are capable of driving more intense saltation events, but this relationship is mediated by other factors on this characteristically narrow beach. As the angle of wind approach becomes more oblique, the fetch distance increases and allows greater opportunity for the saltation system to evolve toward an equilibrium transport state before reaching the foredunes. Whether the theoretically-predicted maximum rate of transport is ever achieved depends on the character of the sand surface (e.g., grain size, slope, roughness, vegetation, moisture content) and on various attributes of the wind field (e.g., average wind speed, unsteadiness, approach angle, flow compression, boundary layer development).
Moisture content is widely acknowledged as an important factor in controlling release of sediment from the beach surface. All other things being equal, the rate of sediment transport over a wet surface is lesser than over a dry surface. On this beach, the moisture effect has two important influences: (a) in a temporal sense, the rate of sediment transport typically decreases in association with rainfall and increases when surface drying takes place; and (b) in a spatio-temporal sense, shoreline excursions associated with nearshore processes (such as wave run-up, storm surge, and tidal excursions) have the effect of constraining the fetch geometry of the beach—i.e., narrowing the width of the beach. Because saturated sand surfaces, such as found in the swash zone, will only reluctantly yield sediments to aeolian entrainment, the available beach surface across which aeolian transport can occur becomes narrower as the sea progressively inundates the beach. Under these constrained conditions, the transport system begins to shut down unless wind angle becomes highly oblique (thereby increasing fetch distance). In this study, maximum sediment transport was usually measured on the mid-beach rather than the upper beach (i.e., closer to the foredunes). This unusual finding is likely because of internal boundary layer development across the beach, which yields a decrease in near-surface wind speed (and hence, transport capacity) in the landward direction. Although widely recognized in the fluid mechanics literature, this decrease in near-surface shear stress as a by-product of a developing boundary layer in the downwind direction has not been adequately investigated in the context of coastal aeolian geomorphology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Ulnar claw hand usually occurs when the ulnar nerve is damaged distally. Claw hand deformity is characterized by metacarpophalangeal hyperextension and interphalangeal flexion, making it impossible ...to oppose the fingers and thumb. Bouvier’s test is used to guide the procedure. Palliative surgery requires prior preparation of paralytic hands. In case of a positive Bouvier’s test, Zancolli’s lasso technique is preferred because of its effectiveness. Capsuloplasty with anteroposterior transosseous fixation is used if the bone is strong enough and when flexor digitorum profondus muscle is inactive and does not allow flexor digitorum superficialis tendon transfer. In case of a negative Bouvier’s test with interphalangeal extension deficit of 45° of less, direct interossei muscle restoration techniques by active transfers are performed. If the interphalangeal extension deficit is more than 45°, proximal interphalangeal arthrodesis is indicated.
Wartenberg first described actively irreducible abduction of the little finger. Wartenberg’s sign is seen when ulnar paralysis occurs, and during ulnar nerve regeneration. Treatment of isolated Wartenberg's sign consists of re-routing the extensor digiti minimi. Among the other techniques, Belmahi’s “tie lasso” is preferred when flexible claw hand is associated with Wartenberg’s sign.
La griffe ulnaire survient généralement lors d’une atteinte distale du nerf ulnaire. La déformation en griffe est caractérisée par une hyperextension métacarpo-phalangienne et une flexion interphalangienne, rendant impossible les prises pollici-digitales. Le test décrit par Bouvier permet de faire le bilan de l’atteinte et d’orienter la prise en charge. La chirurgie palliative nécessite une préparation préalable des mains paralytiques. En cas de positivité du test de Bouvier, la technique du lasso de Zancolli a notre préférence pour sa simplicité, sa rapidité et la facilité des suites opératoires. La capsuloplastie à fixation transosseuse antéropostérieure est utilisée si la qualité de l’os le permet, lorsque le flexor digitorum profondus est inactif, et ne permet pas le prélèvement d’un flexor digitorum superficialis. En cas de négativité du test de Bouvier avec déficit d’extension interphalangien inférieur ou égal à 45 degrés, les techniques de réanimation directe des muscles interossei par des transferts actifs sont utilisées. Si le déficit d’extension interphalangien est supérieur à 45 degrés, une arthrodèse interphalangienne proximale est indiquée.
La description de l’abduction irréductible activement du 5e doigt est due à Wartenberg. On peut observer un signe de Wartenberg lors de la survenue de la paralysie ulnaire et lors de la phase de régénération nerveuse. Le traitement du signe de Wartenberg isolé est dominé par le reroutage de l'extensor digiti minimi. Parmi les autres techniques, celle du "lasso en cravate" de Belmahi a notre préférence dans le cas d’une griffe souple accompagnant un signe de Wartenberg.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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