Exercise for the Treatment of Knee Osteoarthritis

Regular exercise reduces osteoarthritic knee pain and improves functioning. (Strength of Recommendation: A, based on systematic reviews.) Aerobic and strength-training exercises, including land- and water-based exercises, are effective for treating knee osteoarthritis. (Strength of Recommendation: A, based on a randomized controlled trial [RCT].

Associative Retrieval Processes in Episodic Memory

Association and context constitute two of the central ideas in the history of episodic memory research. Following a brief discussion of the history of these ideas, we review data that demonstrate the complementary roles of temporal contiguity and semantic relatedness in determining the order in which subjects recall lists of items and the timing of their successive recalls. These analyses reveal that temporal contiguity effects persist over very long time scales, a result that challenges traditional psychological and neuroscientific models of association. The form of the temporal contiguity effect is conserved across all of the major recall tasks and even appears in item recognition when subjects respond with high confidence. The nearuniversal form of the contiguity effect and its appearance at diverse time scales is shown to place tight constraints on the major theories of association

Detection of Coronal Mass Ejections in V471 Tauri with the Hubble Space Telescope

V471 Tauri, an eclipsing system consisting of a hot DA white dwarf (WD) and a dK2 companion in a 12.5-hour orbit, is the prototype of the pre-cataclysmic binaries. The late-type component is magnetically active, due to its being constrained to rotate synchronously with the short orbital period. During a program of UV spectroscopy of V471 Tau, carried out with the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope, we serendipitously detected two episodes in which transient absorptions in the Si III 1206 A resonance line appeared suddenly, on a timescale of <2 min. The observations were taken in a narrow spectral region around Ly-alpha, and were all obtained near the two quadratures of the binary orbit, i.e., at maximum projected separation (~3.3 Rsun) of the WD and K star. We suggest that these transient features arise when coronal mass ejections (CME's) from the K2 dwarf pass across the line of sight to the WD. Estimates of the velocities, densities, and masses of the events in V471 Tau are generally consistent with the properties of solar CME's. Given our detection of 2 events during 6.8 hr of GHRS observing, along with a consideration of the restricted range of latitudes and longitudes on the K star's surface that can give rise to trajectories passing in front of the WD as seen from Earth, we estimate that the active V471 Tau dK star emits some 100-500 CME's per day, as compared to 1-3 per day for the Sun. The K dwarf's mass-loss rate associated with CME's is at least (5-25) x 10^{-14} Msun/yr, but it may well be orders of magnitude higher if most of the silicon is in ionization states other than Si III.Comment: 24 pages AASTeX, 4 figures. Accepted by Astrophysical Journa

CKS VIII: Eccentricities of Kepler Planets and Tentative Evidence of a High Metallicity Preference for Small Eccentric Planets

Characterizing the dependence of the orbital architectures and formation environments on the eccentricity distribution of planets is vital for understanding planet formation. In this work, we perform statistical eccentricity studies of transiting exoplanets using transit durations measured via Kepler combined with precise and accurate stellar radii from the California-Kepler Survey and Gaia. Compared to previous works that characterized the eccentricity distribution from transit durations, our analysis benefits from both high precision stellar radii ($\sim$3%) and a large sample of $\sim$1000 planets. We observe that that systems with only a single observed transiting planet have a higher mean eccentricity ($\bar{e} \sim 0.21$) than systems with multiple transiting planets ($\bar{e} \sim 0.05$), in agreement with previous studies. We confirm the preference for high and low eccentricity subpopulations among the singly transiting systems. Finally, we show suggestive new evidence that high $e$ planets in the Kepler sample are preferentially found around high metallicity ([Fe/H] $>0$) stars. We conclude by discussing the implications on planetary formation theories

PrimPol bypasses UV photoproducts during eukaryotic chromosomal DNA replication

DNA damage can stall the DNA replication machinery, leading to genomic instability. Thus, numerous mechanisms exist to complete genome duplication in the absence of a pristine DNA template, but identification of the enzymes involved remains incomplete. Here, we establish that Primase-Polymerase (PrimPol; CCDC111), an archaeal-eukaryotic primase (AEP) in eukaryotic cells, is involved in chromosomal DNA replication. PrimPol is required for replication fork progression on ultraviolet (UV) lightdamaged DNA templates, possibly mediated by its ability to catalyze translesion synthesis (TLS) of these lesions. This PrimPol UV lesion bypass pathway is not epistatic with the Pol h-dependent pathway and, as a consequence, protects xeroderma pigmentosum variant (XP-V) patient cells from UV-induced cytotoxicity. In addition, we establish that PrimPol is also required for efficient replication fork progression during an unperturbed S phase. These and other findings indicate that PrimPol is an important player in replication fork progression in eukaryotic cells

Levels of house dust mite allergen in cars [Razine alergena prašinskih grinja u automobilima]

This small study investigated house dust mite (HDM) allergen levels in cars and their owners’ homes in north-east Scotland. Dust samples from twelve households and cars were collected in a standardised manner. The dust samples were extracted and measured for the Dermatophagoides group 2 allergens (Der p 2 and Der f 2) and total soluble protein. Allergen levels at homes tended to be higher than in the cars, but not significantly. However, they significantly correlated with paired car dust samples expressed either per unit weight of dust or soluble protein (rho=0.657; p=0.02 and 0.769; p=0.003, respectively). This points to house-to-car allergen transfer, with the car allergen levels largely reflecting levels in the owner’s home. Car HDM allergen levels were lower than those reported in Brazil and the USA. Twenty-five percent of the houses and none of the cars had allergen levels in dust greater than 2000 ng g-1. This value is often quoted as a threshold for the risk of sensitisation, although a number of studies report increased risk of sensitisation at lower levels. This small study does not allow for characterisation of the distribution of HDM allergen in vehicles in this geographic area, or of the likely levels in other warmer and more humid areas of the UK. Cars and other vehicles are an under-investigated micro-environment for exposure to allergenic material. U ovome smo preliminarnom istraživanju izmjerili razine alergena prašinskih grinja u automobilima i domovima njihovih vlasnika u sjevernoistočnoj Škotskoj. Uzorci prašine uzeti su na standardizirani način iz dvanaest domova i dvanaest odgovarajućih automobila. Nakon ekstrakcije izmjerene su razine 2. skupine alergena grinja roda Dermatophagoides (Der p 2 i Der f 2) te njihove ukupne topljive bjelančevine. Razine alergena u kućama bile su mahom više nego u automobilima, ali ne značajno. Uočena je međutim značajna korelacija njihovih razina s razinama u automobilima, bez obzira na to jesu li iskazane udjelom težine po gramu prašine ili topljivim bjelančevinama (rho=0,657; p=0,02 odnosno 0,769; p=0,003). To upućuje na prijenos alergena iz kuće u auto tj. pokazuje da razine alergena u autima odražavaju razine u domovima njihovih vlasnika. Razine alergena kućnih prašinskih grinja u automobilima u Škotskoj bile su niže od onih izmjerenih u Brazilu i SAD-u. U 25 % domova razina alergena bila je viša od 2000 ng g-1, a ni u jednom uzorku nije izmjerena razina viša od te. Ta se vrijednost često smatra graničnom za rizik od senzitizacije, premda neka istraživanja govore o povišenom riziku od senzitizacije i pri nižim razinama alergena. Rezultati ovog istraživanja ne daju uvida u stvarnu prisutnost alergena kućnih prašinskih grinja u vozilima u sjeveroistočnoj Škotskoj niti upućuju na to kolike bi mogle biti njihove razine u toplijim i vlažnijim krajevima Ujedinjenog Kraljevstva. Automobili i ostala vozila zanemareni su kao izvori izloženosti alergenima

Network approaches for formalizing conceptual models in ecosystem-based management

Funding Intermodel comparisons were supported through funding from the NOAA Integrated Ecosystem Assessment Program. P.S. McDonald’s involvement was funded in part by a grant from Washington Sea Grant, University of Washington, pursuant to National Oceanic and Atmospheric Administration Award number NA14OAR4170078. Funding for RPW was supported by the National Marine Fisheries Service (NMFS)/Sea Grant Population and Ecosystem Dynamics Graduate Fellowship via federal award NA14OAR4170077. Acknowledgements We would like to acknowledge and thank the participants of the NOAA Integrated Ecosystem Assessment Program conceptual network modelling workshop at Baton Rouge, LA in July 2018. The discussions at this meeting formed some of the basis for the ideas presented in this manuscript. We also thank J. Moss and two anonymous reviewers for valuable comments on earlier manuscript drafts. The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the National Marine Fisheries Service, NOAA. Reference to trade names does not imply endorsement by the National Marine Fisheries Service, NOAA. This is NOAA Integrated Ecosystem Assessment Program contribution number 2021_3.Peer reviewedPostprin

Far-Infrared Hydrogen Lasers in the Peculiar Star MWC 349A

Far-infrared hydrogen recombination lines H15(alpha)(169.4 micrometers), H12(alpha)(88.8 micrometers), and H10(alpha)(52.5 micrometers) were detected in the peculiar luminous star MWC 349A from the Kuiper Airborne Observatory. Here it is shown that at least H15(alpha) is strongly amplified, with the probable amplification factor being greater than or about equal to 10(exp 3) and a brightness temperature that is greater than or about equal to 10(exp 7) kelvin. The other two lines also show signs of amplification, although to a lesser degree. Beyond H10(alpha) the amplification apparently vanishes. The newly detected amplified lines fall into the laser wavelength domain. These lasers, as well as the previously detected hydrogen masers may originate in the photoionized circumstellar disk of MWC 349A and constrain the disk's physics and structure