494 research outputs found

    Collapsing granular suspensions

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    A 2D contact dynamics model is proposed as a microscopic description of a collapsing suspension/soil to capture the essential physical processes underlying the dynamics of generation and collapse of the system. Our physical model is compared with real data obtained from in situ measurements performed with a natural collapsing/suspension soil. We show that the shear strength behavior of our collapsing suspension/soil model is very similar to the behavior of this collapsing suspension soil, for both the unperturbed and the perturbed phases of the material.Comment: 7 pages, 5 figures, accepted for publication in EPJ

    Subtyping sub-Saharan esophageal squamous cell carcinoma by comprehensive molecular analysis

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    Esophageal squamous cell carcinoma (ESCC) is endemic in regions of sub-Saharan Africa (SSA), where it is the third most common cancer. Here, we describe whole-exome tumor/normal sequencing and RNA transcriptomic analysis of 59 patients with ESCC in Malawi. We observed similar genetic aberrations as reported in Asian and North American cohorts, including mutations of TP53, CDKN2A, NFE2L2, CHEK2, NOTCH1, FAT1, and FBXW7. Analyses for nonhuman sequences did not reveal evidence for infection with HPV or other occult pathogens. Mutational signature analysis revealed common signatures associated with aging, cytidine deaminase activity (APOBEC), and a third signature of unknown origin, but signatures of inhaled tobacco use, aflatoxin and mismatch repair were notably absent. Based on RNA expression analysis, ESCC could be divided into 3 distinct subtypes, which were distinguished by their expression of cell cycle and neural transcripts. This study demonstrates discrete subtypes of ESCC in SSA, and suggests that the endemic nature of this disease reflects exposure to a carcinogen other than tobacco and oncogenic viruses

    Meniscus treatment and age associated with narrower radiographic joint space width 2–3 years after ACL reconstruction: data from the MOON onsite cohort

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    SummaryObjectiveTo identify risk factors for radiographic signs of post-traumatic osteoarthritis (OA) 2–3 years after anterior cruciate ligament (ACL) reconstruction through multivariable analysis of minimum joint space width (mJSW) differences in a specially designed nested cohort.MethodsA nested cohort within the Multicenter Orthopaedic Outcomes Network (MOON) cohort included 262 patients (148 females, average age 20) injured in sport who underwent ACL reconstruction in a previously uninjured knee, were 35 or younger, and did not have ACL revision or contralateral knee surgery. mJSW on semi-flexed radiographs was measured in the medial compartment using a validated computerized method. A multivariable generalized linear model was constructed to assess mJSW difference between the ACL reconstructed and contralateral control knees while adjusting for potential confounding factors.ResultsUnexpectedly, we found the mean mJSW was 0.35 mm wider in ACL reconstructed than in control knees (5.06 mm (95% CI 4.96–5.15 mm) vs 4.71 mm (95% CI 4.62–4.80 mm), P < 0.001). However, ACL reconstructed knees with meniscectomy had narrower mJSW compared to contralateral normal knees by 0.64 mm (95% C.I. 0.38–0.90 mm) (P < 0.001). Age (P < 0.001) and meniscus repair (P = 0.001) were also significantly associated with mJSW difference.ConclusionSemi-flexed radiographs can detect differences in mJSW between ACL reconstructed and contralateral normal knees 2–3 years following ACL reconstruction, and the unexpected wider mJSW in ACL reconstructed knees may represent the earliest manifestation of post-traumatic osteoarthritis and warrants further study

    Fungi Associated with the Hemlock Woolly Adelgid, Adelges tsugae, and Assessment of Entomopathogenic Isolates for Management

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    Fungi associated with the hemlock wooly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), were collected throughout the eastern USA and southern China. Twenty fungal genera were identified, as were 79 entomopathogenic isolates, including: Lecanicillium lecanii (Zimmermann) (Hypocreales: Insertae sedis), Isaria farinosa (Holm: Fries.) (Cordycipitaceae), Beauveria bassiana (Balasamo) (Hyphomycetes), and Fusarium spp (Nectriaceae). The remaining fungal genera associated with insect cadavers were similar for both the USA and China collections, although the abundance of Acremonium (Hypocreaceae) was greater in China. The entomopathogenic isolates were assayed for efficacy against Myzus persicae (Sulzer) (Homoptera: Aphididae) and yielded mortality ranging from 3 to 92%. Ten isolates demonstrating the highest efficacy were further assessed for efficacy against field-collected A. tsugae under laboratory conditions. Overall, two B. bassiana, one L. lecanii, and a strain of Metarhizium anisopliae (Metchnikoff) (Hypocreales: Clavicipitaceae), demonstrated significantly higher efficacy against A. tsugae than the others. Isolates were further evaluated for conidial production, germination rate and colony growth at four temperatures representative of field conditions. All isolates were determined to be mesophiles with optimal temperature between 25–30° C. In general, conidial production increased with temperature, though two I. farinosa produced significantly more conidia at cooler temperatures. When efficacy values were compared with conidial production and temperature tolerances, Agricultural Research Service Collection of Entomopathogenic Fungi (ARSEF) 1080, 5170, and 5798 had characteristics comparable to the industrial B. bassiana strain GHA

    Alpha scattering and capture reactions in the A = 7 system at low energies

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    Differential cross sections for 3^3He-α\alpha scattering were measured in the energy range up to 3 MeV. These data together with other available experimental results for 3^3He +α+ \alpha and 3^3H +α+ \alpha scattering were analyzed in the framework of the optical model using double-folded potentials. The optical potentials obtained were used to calculate the astrophysical S-factors of the capture reactions 3^3He(α,γ)7(\alpha,\gamma)^7Be and 3^3H(α,γ)7(\alpha,\gamma)^7Li, and the branching ratios for the transitions into the two final 7^7Be and 7^7Li bound states, respectively. For 3^3He(α,γ)7(\alpha,\gamma)^7Be excellent agreement between calculated and experimental data is obtained. For 3^3H(α,γ)7(\alpha,\gamma)^7Li a S(0)S(0) value has been found which is a factor of about 1.5 larger than the adopted value. For both capture reactions a similar branching ratio of R=σ(γ1)/σ(γ0)0.43R = \sigma(\gamma_1)/\sigma(\gamma_0) \approx 0.43 has been obtained.Comment: submitted to Phys.Rev.C, 34 pages, figures available from one of the authors, LaTeX with RevTeX, IK-TUW-Preprint 930540

    Fluorescent carbon dioxide indicators

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    Over the last decade, fluorescence has become the dominant tool in biotechnology and medical imaging. These exciting advances have been underpinned by the advances in time-resolved techniques and instrumentation, probe design, chemical / biochemical sensing, coupled with our furthered knowledge in biology. Complementary volumes 9 and 10, Advanced Concepts of Fluorescence Sensing: Small Molecule Sensing and Advanced Concepts of Fluorescence Sensing: Macromolecular Sensing, aim to summarize the current state of the art in fluorescent sensing. For this reason, Drs. Geddes and Lakowicz have invited chapters, encompassing a broad range of fluorescence sensing techniques. Some chapters deal with small molecule sensors, such as for anions, cations, and CO2, while others summarize recent advances in protein-based and macromolecular sensors. The Editors have, however, not included DNA or RNA based sensing in this volume, as this were reviewed in Volume 7 and is to be the subject of a more detailed volume in the near future

    Strength of the 18F(p, α)15O resonance at Ec.m. = 330 keV

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    The astrophysical rate of the 18F(p,α)15O reaction at nova temperatures is critical to understanding production of the radioisotope 18F, which may be used to constrain nova models via observations with the coming generation of satellite-based γ-ray telescopes. As such, a measurement is made of the strength of this resonance using a radioactive 18F beam at the HRIBF. As a result, it is indicated that the 18F(p,α)15O reaction rate is lower than previous estimates by a factor of ∼2

    The 22-Year Hale Cycle in cosmic ray flux: evidence for direct heliospheric modulation

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    The ability to predict times of greater galactic cosmic ray (GCR) fluxes is important for reducing the hazards caused by these particles to satellite communications, aviation, or astronauts. The 11-year solar-cycle variation in cosmic rays is highly correlated with the strength of the heliospheric magnetic field. Differences in GCR flux during alternate solar cycles yield a 22-year cycle, known as the Hale Cycle, which is thought to be due to different particle drift patterns when the northern solar pole has predominantly positive (denoted as qA>0 cycle) or negative (qA0 cycles than for qA0 and more sharply peaked for qA0 solar cycles, when the difference in GCR flux is most apparent. This suggests that particle drifts may not be the sole mechanism responsible for the Hale Cycle in GCR flux at Earth. However, we also demonstrate that these polarity-dependent heliospheric differences are evident during the space-age but are much less clear in earlier data: using geomagnetic reconstructions, we show that for the period of 1905 - 1965, alternate polarities do not give as significant a difference during the declining phase of the solar cycle. Thus we suggest that the 22-year cycle in cosmic-ray flux is at least partly the result of direct modulation by the heliospheric magnetic field and that this effect may be primarily limited to the grand solar maximum of the space-age

    Comparative analysis of the genes UL1 through UL7 of the duck enteritis virus and other herpesviruses of the subfamily Alphaherpesvirinae

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    The nucleotide sequences of eight open reading frames (ORFs) located at the 5' end of the unique long region of the duck enteritis virus (DEV) Clone-03 strain were determined. The genes identified were designated UL1, UL2, UL3, UL4, UL5, UL6 and UL7 homologues of the herpes simplex virus 1 (HSV-1). The DEV UL3.5 located between UL3 and UL4 had no homologue in the HSV-1. The arrangement and transcription orientation of the eight genes were collinear with their homologues in the HSV-1. Phylogenetic trees were constructed based on the alignments of the deduced amino acids of eight proteins with their homologues in 12 alpha-herpesviruses. In the UL1, UL3, UL3.5, UL5 and UL7 proteins trees, the branches were more closely related to the genus Mardivirus. However, the UL2, UL4, and UL6 proteins phylogenetic trees indicated a large distance from Mardivirus, indicating that the DEV evolved differently from other viruses in the subfamily Alphaherpesvirinae and formed a single branch within this subfamily
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