1,240 research outputs found

    SN~1991T: Reflections of Past Glory

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    We have obtained photometry and spectra of SN~1991T which extend more than 1000 days past maximum light, by far the longest a SN~Ia has been followed. Although SN~1991T exhibited nearly normal photometric behavior in the first 400 days following maximum, by 600 days its decline had slowed, and by 950~days the supernova brightness was consistent with a constant apparent magnitude of mB=21.30m_B=21.30. Spectra near maximum showed minor variations on the SN~Ia theme which grew less conspicuous during the exponential decline. At 270 days the nebular spectrum was composed of Fe and Co lines common to SNe~Ia. However, by 750 days past maximum light, these lines had shifted in wavelength, and were superimposed on a strong blue continuum. The luminosity of SN~1991T at 950 days is more than 9.0×1038(D/13 Mpc)29.0\times10^{38}(D/13~{\rm Mpc})^2~ergs~s−1^{-1} with a rate of decline of less than 0.040.04 mags/100~days. We show that this emission is likely to be light that was emitted by SN~1991T near maximum light which has reflected from foreground dust, much like the light echos observed around SN~1987A.Comment: 15 pages (includes figures and tables) uuencoded compressed postscript, CfA Preprint - To Appear in ApJ

    Abridged bibliography of photographic interpretation : selected with emphasis upon keys, techniques, and research

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    This bibliography, PIC Report No. 102A/50, is a literature review of the applications of aerial photography. It is a classified list covering applications for archaeology, engineering, forestry, geography, geology, soil science, and the study of vegetation. The copy used to create this digital document was borrowed from the Maury Oceanographic Library, Stennis Space Center, MS

    Aminopyralid + Metsulfuron-Methyl for Cost-Effective Control of Hard to Kill Pasture Weeds

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    This paper summarises research trials conducted from 2010 to 2013 to determine speed of brownout and efficacy of an aminopyralid + metsulfuron-methyl herbicide product in pastures compared to metsulfuron alone and current commercial standards

    Author Correction: Cancer Testis Antigen Promotes Triple Negative Breast Cancer Metastasis and is Traceable in the Circulating Extracellular Vesicles (Scientific Reports, (2019), 9, 1, (11632), 10.1038/s41598-019-48064-w)

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    Triple negative breast cancer (TNBC) has poor survival, exhibits rapid metastases, lacks targeted therapies and reliable prognostic markers. Here, we examined metastasis promoting role of cancer testis antigen SPANXB1 in TNBC and its utility as a therapeutic target and prognostic biomarker. Expression pattern of SPANXB1 was determined using matched primary cancer, lymph node metastatic tissues and circulating small extracellular vesicles (sEVs). cDNA microarray analysis of TNBC cells stably integrated with a metastasis suppressor SH3GL2 identified SPANXB1 as a potential target gene. TNBC cells overexpressing SH3GL2 exhibited decreased levels of both SPANXB1 mRNA and protein. Silencing of SPANXB1 reduced migration, invasion and reactive oxygen species production of TNBC cells. SPANXB1 depletion augmented SH3GL2 expression and decreased RAC-1, FAK, A-Actinin and Vinculin expression. Phenotypic and molecular changes were reversed upon SPANXB1 re-expression. SPANXB1 overexpressing breast cancer cells with an enhanced SPANXB1:SH3GL2 ratio achieved pulmonary metastasis within 5 weeks, whereas controls cells failed to do so. Altered expression of SPANXB1 was detected in the sEVs of SPANXB1 transduced cells. Exclusive expression of SPANXB1 was traceable in circulating sEVs, which was associated with TNBC progression. SPANXB1 represents a novel and ideal therapeutic target for blocking TNBC metastases due to its unique expression pattern and may function as an EV based prognostic marker to improve TNBC survival. Uniquely restricted expression of SPANXB1 in TNBCs, makes it an ideal candidate for targeted therapeutics and prognostication

    Variable strength of forest stand attributes and weather conditions on the questing activity of Ixodes ricinus ticks over years in managed forests

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    Given the ever-increasing human impact through land use and climate change on the environment, we crucially need to achieve a better understanding of those factors that influence the questing activity of ixodid ticks, a major disease-transmitting vector in temperate forests. We investigated variation in the relative questing nymph densities of Ixodes ricinus in differently managed forest types for three years (2008–2010) in SW Germany by drag sampling. We used a hierarchical Bayesian modeling approach to examine the relative effects of habitat and weather and to consider possible nested structures of habitat and climate forces. The questing activity of nymphs was considerably larger in young forest successional stages of thicket compared with pole wood and timber stages. Questing nymph density increased markedly with milder winter temperatures. Generally, the relative strength of the various environmental forces on questing nymph density differed across years. In particular, winter temperature had a negative effect on tick activity across sites in 2008 in contrast to the overall effect of temperature across years. Our results suggest that forest management practices have important impacts on questing nymph density. Variable weather conditions, however, might override the effects of forest management practices on the fluctuations and dynamics of tick populations and activity over years, in particular, the preceding winter temperatures. Therefore, robust predictions and the detection of possible interactions and nested structures of habitat and climate forces can only be quantified through the collection of long-term data. Such data are particularly important with regard to future scenarios of forest management and climate warming

    The importance of deep venous reflux velocity as a determinant of outcome in patients with combined superficial and deep venous reflux treated with endovenous saphenous ablation

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    INTRODUCTION: Twenty to thirty percent of patients with symptomatic chronic venous insufficiency (CVI) are found to have combined superficial and deep venous reflux on duplex testing. It is currently unclear whether endovenous ablation (EVA) of the saphenous vein will result in correction of CVI without addressing the deep venous reflux. In this study, we examined deep venous reflux velocities to determine whether these would predict outcome after endovenous ablation. METHODS: Patients with symptomatic CVI and both saphenous and deep venous reflux were identified using duplex ultrasonography. Reflux times and maximal reflux velocity (MRV) in each examined vein segment were determined. In each limb, the venous filling index (VFI) and the venous clinical severity score (VCSS) were obtained both before and after laser ablation of the great and/or small saphenous veins. Preoperative venous reflux velocities were correlated with improvement in VFI and VCSS after ablation. RESULTS: 75 limbs with both deep and superficial venous reflux were identified. Seventy-five percent of limbs were CEAP clinical class 3 or 4 and the other 25% were class 5 or 6. Forty limbs demonstrated deep venous reflux in the femoral and/or popliteal vein. After EVA, significant improvements in VFI and VCSS were seen, but this depended on MRV in the deep vein. When MRV in the popliteal or femoral vein was 10 cm/sec as measured by both VFI (P = .01) and VCSS (P = .03). In 35 limbs, deep venous reflux was identified only in the CFV. In this group, the average pre-procedure VFI (6.54 +/- 3.9 cc/sec) decreased significantly to 2.2 +/- 1.9 cc/sec (P < .001) and the VCSS improved markedly from 7.0 +/- 2.8 to 1.3 +/- 1.4 (P < .001). CONCLUSIONS: EVA of the saphenous veins can be performed in patients with concomitant deep venous insufficiency with hemodynamic and clinical improvement in most cases. Patients with popliteal or femoral reflux velocities lower than 10 cm/sec usually experience marked improvement in both the VFI and the VCSS. Patients with femoral or popliteal reflux velocities greater than 10 cm/sec have a high incidence of persistent symptoms after EVA

    Genome-wide scan identifies novel genetic loci regulating salivary metabolite levels.

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    Saliva, as a biofluid, is inexpensive and non-invasive to obtain, and provides a vital tool to investigate oral health and its interaction with systemic health conditions. There is growing interest in salivary biomarkers for systemic diseases, notably cardiovascular disease. Whereas hundreds of genetic loci have been shown to be involved in the regulation of blood metabolites, leading to significant insights into the pathogenesis of complex human diseases, little is known about the impact of host genetics on salivary metabolites. Here we report the first genome-wide association study exploring 476 salivary metabolites in 1419 subjects from the TwinsUK cohort (discovery phase), followed by replication in the Study of Health in Pomerania (SHIP-2) cohort. A total of 14 distinct locus-metabolite associations were identified in the discovery phase, most of which were replicated in SHIP-2. While only a limited number of the loci that are known to regulate blood metabolites were also associated with salivary metabolites in our study, we identified several novel saliva-specific locus-metabolite associations, including associations for the AGMAT (with the metabolites 4-guanidinobutanoate and beta-guanidinopropanoate), ATP13A5 (with the metabolite creatinine) and DPYS (with the metabolites 3-ureidopropionate and 3-ureidoisobutyrate) loci. Our study suggests that there may be regulatory pathways of particular relevance to the salivary metabolome. In addition, some of our findings may have clinical significance, such as the utility of the pyrimidine (uracil) degradation metabolites in predicting 5-fluorouracil toxicity and the role of the agmatine pathway metabolites as biomarkers of oral health

    Measurement of laser intensities approaching 10 15 W/cm 2 with an accuracy of 1%

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    Accurate knowledge of the intensity of focused ultrashort laser pulses is crucial to the correct interpretation of experimental results in strong-field physics. We have developed a technique to measure laser intensities approaching 1015W/cm2 with an accu

    SN 1991T: Reflections of Past Glory

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    We have obtained photometry and spectra of SN 1991T which extend more than 1000 days past maximum light, by far the longest a SN Ia has been followed. Although SN 1991T exhibited nearly photometric behavior in the first 400 days following maximum, by 600 days its decline had slowed, and by 950 days the supernova brightness was consistent with a constant apparent magnitude of m_B_ = 21.30. Spectra near maximum showed minor variations on the SN Ia theme which grew less conspicuous during the exponential decline. At 270 days the nebular spectrum was composed of Fe and Co lines common to SN Ia. However, by 750 days past maximum light, these lines had shifted in wavelength, and were superposed on a strong blue continuum. The luminosity of SN 1991T at 950 days is more than 9.0 x 10^38^(D/13 Mpc)^2^ ergs s^-1^ with a rate of decline of less than 0.04 mag per 100 days. We show that this emission is likely to be light that was emitted by SN 1991T near maximum light which has reflected from foreground dust, much like the light echos observed around SN 1987A.This work is supported in part by NSF grants AST 92-18475 and AST 91-15174, as well as NASA grants NAG 5-841 and NGT-51002

    Self-directed learning of basic musculoskeletal ultrasound among rheumatologists in the United States

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    Objective Because musculoskeletal ultrasound (MSUS) is highly user dependent, we aimed to establish whether non-mentored learning of MSUS is sufficient to achieve the same level of diagnostic accuracy and scanning reliability as has been achieved by rheumatologists recognized as international experts in MSUS. Methods A group of 8 rheumatologists with more experience in MSUS and 8 rheumatologists with less experience in MSUS participated in an MSUS exercise to assess patients with musculoskeletal abnormalities commonly seen in a rheumatology practice. Patients' established diagnoses were obtained from chart review (gout, osteoarthritis, rotator cuff syndrome, rheumatoid arthritis, and seronegative arthritis). Two examining groups were formed, each composed of 4 less experienced and 4 more experienced examiners. Each group scanned 1 predefined body region (hand, wrist, elbow, shoulder, knee, or ankle) in each of 8 patients, blinded to medical history and physical examination. Structural abnormalities were noted with dichotomous answers, and an open-ended answer was used for the final diagnosis. Results Less experienced and more experienced examiners achieved the same diagnostic accuracy (US-established diagnosis versus chart review diagnosis). The interrater reliability for tissue pathology was slightly higher for more experienced versus less experienced examiners (Κ = 0.43 versus Κ = 0.34; P = 0.001). Conclusion Non-mentored training in MSUS can lead to the achievement of diagnostic accuracy in MSUS comparable to that achieved by highly experienced international experts. Reliability may increase slightly with additional experience. Further study is needed to determine the minimal training requirement to achieve proficiency in MSUS.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65036/1/20063_ftp.pd
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