3,255 research outputs found

    Long-Term Evolution of Massive-Star Post-Common Envelope Circumbinary Disks and the Environments of Fast Luminous Transients

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    If the envelope of a massive star is not entirely removed during common envelope (CE) interaction with an orbiting compact (e.g., black hole [BH] or neutron star [NS]) companion, the residual bound material eventually cools, forming a centrifugally-supported disk around the binary containing the stripped He core. We present a time-dependent height-integrated model for the long-term evolution of post-CE circumbinary disks (CBD), accounting for mass and angular momentum exchange with the binary and irradiation heating by the He core and photoevaporation wind mass-loss. A large fraction of the CBD's mass is accreted prior to its outwards viscous spreading and wind-dispersal on a timescale ~10^{4}-10^{5} yr, driving significant changes in the binary separation, even for disks containing ~ 10% of the original envelope mass. Insofar that the CBD lifetime is comparable to the thermal (and, potentially, nuclear) timescale of the He core, over which a second mass-transfer episode onto the companion can occur, the presence of the CBD could impact the stability of this key phase. Disruption of the He core by the BH/NS would result in a jetted energetic explosion into the dense gaseous CBD (<~10^{15} cm) and its wind (>~ 10^{16} cm), consistent with the environments of luminous fast blue optical transients like AT2018cow. Evolved He cores which undergo core-collapse still embedded in their CBD could generate Type Ibn/Icn supernovae. Thousands of dusty wind-shrouded massive-star CBD may be detectable as extragalactic luminous infrared sources with the Roman Space Telescope; synchrotron radio nebulae powered by the CBD-fed BH/NS may accompany these systems.Comment: 26 pages, 11 figure

    The long-term effect of complex regional pain syndrome type 1 on disability and quality of life after foot injury

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    PURPOSE: To study the long-term evolution of patients with lower-limb Complex Regional Pain Syndrome (CRPS), focusing on functional and proprioceptive aspects and quality of life. METHODS: In 20 patients suffering from chronic distal lower-limb CRPS diagnosed using Budapest criteria, we assessed joint position sense and strength of the knee muscles at the CRPS and unaffected leg, functional exercise capacity, pain, CRPS severity score, quality of life and kinesiophobia. Similar assessments were performed in 20 age-matched controls. RESULTS: The joint position performance (at 45°) was significantly lower for the CRPS leg as compared to controls. The knee extensor strength of the CRPS leg was significantly reduced as compared to the unaffected leg (−27%) and controls (−42%). CRPS patients showed significantly reduced performance at the 6 min-walk test as compared to their age group predicted value and controls. Patients suffering from CRPS for 3.8 years in average still exhibit high pain, severity and kinesiophobia scores. CONCLUSIONS: Long-term deficits in strength and proprioceptive impairments are observed at the knee joint of the CRPS leg. This persistent functional disability has significant repercussions on the quality of life. We highlight the importance of including strength and proprioceptive exercises in the therapeutic approaches for CPRS patients

    Bronchopulmonary Dysplasia: A Five-Year Retrospective Cohort Study on Differences in Clinical Characteristics and Morbidities According to Severity Grading

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    Introduction: Bronchopulmonary dysplasia (BPD) is the most common complication associated with extreme prematurity. Although several criteria defining severity were developed over time, there are a few studies describing the differences in BPD phenotype and neonatal morbidities and complications between severity groups. We aimed to describe these differences in BPD patients of a neonatal intensive care unit (NICU). Methods: We conducted an observational retrospective cohort study through a medical record review over a five-year period. Participants were newborns admitted to an NICU who were diagnosed with BPD. We performed a descriptive statistical analysis of gestational complications and the use of antenatal corticosteroid therapy, birth-related data, and complications throughout the NICU stay, as well as the respiratory support used. We also compared different severity groups across these variables. The patients were divided into severe and non-severe BPD using the severity criteria of the 2001 NICHD/NHLBI/ORD consensus workshop. Results: A total of 101 newborns with BPD participated in the study and 73 had data on BPD severity. The median gestational age was 27 weeks, ranging from 23 to 32 weeks. Of these 73 newborns, 36 had mild BPD (49.3%), 10 had moderate BPD (13.7%), and 27 had severe BPD (37.0%). When comparing severe and non-severe BPD, we found that extreme prematurity, extremely low birth weight, and small size for gestational age were more frequent in the severe BPD group (p-value=0.012, p-value<0.001, and p-value=0.012, respectively). Infants with severe BPD had a longer duration of invasive ventilation than those with mild or moderate BPD (p-value<0.001). Late sepsis, necrotizing enterocolitis, severe brain injury, and retinopathy of prematurity were more frequent in severe BPD (p-value=0.017, p-value=0.045, p-value=0.033, p-value=0.003, respectively). Discussion: Previously published evidence describing causal links between BPD development and comorbidities exists but data on their impact on BPD severity are scarce. In our study, severe BPD seemed to be associated with a higher frequency of comorbidities and complications. Further studies are needed to ascertain the impact of each morbidity on the severity of BPD and if measures to prevent them could lead to potentially milder BPD disease.info:eu-repo/semantics/publishedVersio

    Koncentracije serumskog prokalcitonina i C-reaktivnog proteina u pasa s degenerativnom bolešću mitralnog zaliska i infektivnim endokarditisom

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    This study aimed to investigate the clinical significance of serum C-reactive protein (CRP) and procalcitonin (PCT) concentrations in dogs with degenerative mitral valve disease (DMVD) and infective endocarditis. It also aimed to evaluate whether there is a relationship between the degree of disease and serum PCT and CRP concentrations. A total of 100 dogs with MVD were prospectively recruited into the study. According to clinical/laboratory signs and echocardiography, the dogs were divided into infective and degenerative groups. The degenerative group was also classified into four stages based on the American College of Veterinary Internal Medicine (ACVIM) guidelines (Stages A-D). Serum PCT and CRP concentrations were determined with dog-specific commercial test kits. The serum CRP (P<0.05) and PCT (P<0.001) concentrations in the infective group were significantly higher than the degenerative group. In the degenerative group, the serum CRP concentration of stage D dogs was significantly higher than the other stages (P<0.001), and the degree of disease correlated significantly positively with serum CRP concentration (r=0.531 P=0.000). In conclusion, serum CRP and PCT concentrations may aid traditional diagnostic techniques to differentiate infective and degenerative mitral valve disease. This study also demonstrated that serum CRP concentrations were elevated in Stage D dogs, and that there is a positive correlation between the degree of disease and serum CRP concentration. This can be useful in determining the severity of the inflammatory state in dogs with DMVD.Cilj rada bio je istražiti kliničku važnost serumskih koncentracija C-reaktivnog proteina (CRP) i prokalcitonina (PCT) u pasa s degenerativnom bolešću mitralnog zaliska (DMVD) i infektivnim endokarditisom. Također, cilj je bio i procijeniti postoji li povezanost između stupnja bolesti i serumskih koncentracija PCT-a i CRP-a. U prospektivno istraživanje uključeno je ukupno je 100 pasa s MVD-om. Prema kliničko laboratorijskim znakovima i ehokardiografiji psi su podijeljeni u skupinu s infektivnom i skupinu s degenerativnom bolešću. Psi s degenerativnom bolešću razvrstani su u četiri stadija (A-D) prema smjernicama American College of Veterinary Internal Medicine (ACVIM). Koncentracije serumskog PCT-a i CRP-a određene su komercijalnim testnim setovima specifičnima za pse. Koncentracije serumskog CRP-a i PCT-a u skupini pasa s infektivnom bolešću bile su znakovito više (P<0,05 i P<0,001) nego one u skupini pasa s degenerativnom bolešću. U skupini s degenerativnom bolešću serumske koncentracije CRP-a u pasa sa stadijem D bile su znakovito više nego u pasa s ostalim stadijima (P<0,001). Stupanj bolesti bio je u znakovitoj pozitivnoj korelaciji sa serumskim koncentracijama CRP-a (r = 0,531, P=0,000). Zaključno, serumske koncentracije CRP-a i PCT-a mogu pomoći tradicionalnim dijagnostičkim metodama u razlikovanju infektivne i degenerativne bolesti mitralnog zaliska. Istraživanje je pokazalo i povišene serumske koncentracije CRP-a u pasa sa stadijem D te pozitivnu korelaciju između stupnja bolesti i koncentracije CRP-a. Navedeno može biti korisno pri procjeni težine upalnog stanja u pasa s DMVD-om

    Metatarsophalangeal joint pain in psoriatic arthritis: a cross-sectional study

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    Methods. Thirty-four consecutive patients with PsA (mean age 45.3 years, 65% female, mean disease duration 9.9 years) and 22 control participants (mean age 37.9 years, 64% female) underwent clinical and US examination to determine the presence of pain, swelling, synovitis, erosions, effusions and submetatarsal bursae at the MTP joints. Mean barefoot peak plantar pressures were determined at each MTP joint. Levels of pain, US-determined pathology and peak pressures were compared between groups. Binary logistic regression was used to identify demographic, clinical examination-derived, US-derived and plantar pressure predictors of pain at the MTP joints in the PsA group. Results. The presence of pain, deformity, synovitis, erosions (P &amp;lt; 0.001) and submetatarsal bursae and peak plantar pressure at MTP 3 (P &amp;lt; 0.05) were significantly higher in the PsA group. MTP joint pain in PsA was independently predicted by high BMI, female gender and the presence of joint subluxation, synovitis and erosion. Conclusion. These results suggest local inflammatory and structural factors, together with systemic factors (gender, BMI), are predominantly responsible for painful MTP joints in PsA, with no clear role for plantar pressure characteristics

    Conical-Intersection Topographies Suggest That Ribose Exhibits Enhanced UV Photostability

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    Carbohydrates are essential building blocks of life that assume a multitude of biological functions in all living organisms found on Earth. It was recently reported that ribose was identified in UV-irradiated interstellar ice analogs, which suggests that it can be found on comets and that it may have been transported to Earth via the impact of comets. Herein, we present computational results obtained with multiconfigurational ab initio quantum-chemical methods showing that various photochemical processes for radiationless deactivation are available for photoexcited ribose. These processes are driven by nσ* states and involve either O–H- or endocyclic or exocyclic C–O-bond elongation whereby a conical intersection with the electronic ground state becomes accessible. The local topography of the potential-energy surfaces around these conical intersections suggests that these intersections mediate efficient radiationless deactivation and favor regeneration of the initially photoexcited ground-state reactant. These findings indicate that ribose found in interstellar space can be expected to be highly photostable upon irradiation with UV starlight, which could be of relevance in the field of astrobiology

    Short-Term Pain and Long-Term Gain: Using Phased-In Minimum Size Limits to Rebuild Stocks-the Pacific Bluefin Tuna Example

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    Like many stocks, the Pacific Bluefin Tuna Thunnus orientalis has been considerably depleted. High exploitation rates on very young fish have reduced the spawning stock biomass (SSB) to 2.6% of the unexploited level. We provide a framework for exploring potential benefits of minimum size regulations as a mechanism for rebuilding stocks, and we illustrate the approach using simulations patterned after Pacific Bluefin Tuna dynamics. We attempt to mitigate short-term losses in yield by considering a phased-in management strategy. With this approach, the minimum size limit (MSL) is gradually increased as biomass rebuilds, giving fishing communities time to adjust to new restrictions. We estimated short- and long-term effects of different MSLs on yield and biomass by using data from the 2016 assessment. A variety of scenarios was considered for growth compensation, discard mortality, and interest rates. The long-term value of the fishery was maximized by setting an MSL of 92 cm FL, which resulted in a 70% loss in yield during the first year (short-term pain). By implementing the MSL in two phases (64 cm FL in year 1; 92 cm FL in subsequent years), the long-term value of the fishery was maintained, and the short-term pain was reduced to a maximum 46% loss in yield during any 1 year. Under a three-phase implementation (55 cm FL in year 1; 77 cm FL in year 2; and 92 cm FL in subsequent years), the short-term pain was further reduced to a maximum loss of 30% during any 1 year. With no discard mortality, long-term yield increased by 165% and SSB increased 13-fold (to 33% of virgin SSB), regardless of the number of phases used. Long-term benefits were quickly diminished with increasing discard mortality. This simulation approach is widely applicable to cases where minimum size changes are contemplated; for Pacific Bluefin Tuna, our simulations demonstrate that size limits should be considered

    Orchardgrass (Dactylis glomerata L.) EST and SSR marker development, annotation, and transferability.

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    Orchardgrass, or cocksfoot [Dactylis glomerata (L.)], has been naturalized on nearly every continent and is a commonly used species for forage and hay production. All major cultivated varieties of orchardgrass are autotetraploid, and few tools or information are available for functional and comparative genetic analyses and improvement of the species. To improve the genetic resources for orchardgrass, we have developed an EST library and SSR markers from salt, drought, and cold stressed tissues. The ESTs were bi-directionally sequenced from clones and combined into 17,373 unigenes. Unigenes were annotated based on putative orthology to genes from rice, Triticeae grasses, other Poaceae, Arabidopsis, and the non-redundant database of the NCBI. Of 1,162 SSR markers developed, approximately 80% showed amplification products across a set of orchardgrass germplasm, and 40% across related Festuca and Lolium species. When orchardgrass subspecies were genotyped using 33 SSR markers their within-accession similarity values ranged from 0.44 to 0.71, with Mediterranean accessions having a higher similarity. The total number of genotyped bands was greater for tetraploid accessions compared to diploid accessions. Clustering analysis indicated grouping of Mediterranean subspecies and central Asian subspecies, while the D. glomerata ssp. aschersoniana was closest related to three cultivated varieties

    Harnessing the extracellular bacterial production of nanoscale cobalt ferrite with exploitable magnetic properties

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    Nanoscale ferrimagnetic particles have a diverse range of uses from directed cancer therapy and drug delivery systems to magnetic recording media and transducers. Such applications require the production of monodisperse nanoparticles with well-controlled size, composition, and magnetic properties. To fabricate these materials purely using synthetic methods is costly in both environmental and economical terms. However, metal-reducing microorganisms offer an untapped resource to produce these materials. Here, the Fe(III)-reducing bacterium Geobacter sulfurreducens is used to synthesize magnetic iron oxide nanoparticles. A combination of electron microscopy, soft X-ray spectroscopy, and magnetometry techniques was employed to show that this method of biosynthesis results in high yields of crystalline nanoparticles with a narrow size distribution and magnetic properties equal to the best chemically synthesized materials. In particular, it is demonstrated here that cobalt ferrite (CoFe2O4) nanoparticles with low temperature coercivity approaching 8 kOe and an effective anisotropy constant of ∼106 erg cm−3 can be manufactured through this biotechnological route. The dramatic enhancement in the magnetic properties of the nanoparticles by the introduction of high quantities of Co into the spinel structure represents a significant advance over previous biomineralization studies in this area using magnetotactic bacteria. The successful production of nanoparticulate ferrites achieved in this study at high yields could open up the way for the scaled-up industrial manufacture of nanoparticles using environmentally benign methodologies
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