3,817 research outputs found
In Situ Resistance Measurements of Strained Carbon Nanotubes
We investigate the response of multi-walled carbon nanotubes to mechanical
strain applied with an Atomic Force Microscope (AFM) probe. We find that in
some samples, changes in the contact resistance dominate the measured
resistance change. In others, strain large enough to fracture the tube can be
applied without a significant change in the contact resistance. In this case we
observe that enough force is applied to break the tube without any change in
resistance until the tube fails. We have also manipulated the ends of the
broken tube back in contact with each other, re-establishing a finite
resistance. We observe that in this broken configuration the resistance of the
sample is tunable to values 15-350 kW greater than prior to breaking.Comment: Submitted to Applied Physics Letter
Optical and Infrared Photometry of the Unusual Type Ia Supernova 2000cx
We present optical and infrared photometry of the unusual Type Ia supernova
2000cx. With the data of Li et al. (2001) and Jha (2002), this comprises the
largest dataset ever assembled for a Type Ia SN, more than 600 points in
UBVRIJHK. We confirm the finding of Li et al. regarding the unusually blue B-V
colors as SN 2000cx entered the nebular phase. Its I-band secondary hump was
extremely weak given its B-band decline rate. The V minus near infrared colors
likewise do not match loci based on other slowly declining Type Ia SNe, though
V-K is the least ``abnormal''. In several ways SN 2000cx resembles other slow
decliners, given its B-band decline rate (Delta m_15(B) = 0.93), the appearance
of Fe III lines and weakness of Si II in its pre-maximum spectrum, the V-K
colors and post-maximum V-H colors. If the distance modulus derived from
Surface Brightness Fluctuations of the host galaxy is correct, we find that the
rate of light increase prior to maximum, the characteristics of the bolometric
light curve, and the implied absolute magnitude at maximum are all consistent
with a sub-luminous object with Delta m_15(B) ~ 1.6-1.7 having a higher than
normal kinetic energy.Comment: 46 pages, 17 figures, to be published in Publications of the
Astronomical Society of the Pacifi
NEOADJUVANT WEEKLY NAB-PACLITAXEL PLUS CARBOPLATIN FOLLOWED BY DOXORUBICIN PLUS CYCLOPHOSPHAMIDE WITH BEVACIZUMAB ADDED CONCURRENTLY TO CHEMOTHERAPY FOR OPERABLE TRIPLE-NEGATIVE INVASIVE BREAST CANCER
Purpose: This phase II neoadjuvant study investigated whether nab paclitaxel, carboplatin and bevacizumab given before neoadjuvant doxorubicin/cyclophosphamide (AC) produced higher pathologic complete response (pCR) rates in triple- negative breast cancer (TNBC) compared with historical results achieved with standard anthracycline/taxane regimens. Patients and Methods: Eligible patients with operable TNBC ≥2 cm received four cycles of carboplatin (area under the curve 6, day 1) plus nab-paclitaxel (100 mg/m2, days 1, 8 and 15) every 28 days, followed by four 14-day cycles of AC neoadjuvantly, with bevacizumab 10 mg/kg every 14 days for the rst 6 cycles of neoadjuvant chemotherapy, resuming postoperatively to complete 1 year of antibody treatment. In breast pCR and pCR (breast + nodes) were primary and secondary endpoints, respectively. Results: Due to slow accrual, the study was closed after enrollment of 42 of 60 planned patients. Of the 38 patients who underwent surgery (ef cacy population), 22 (58%) achieved an in-breast pCR and 19 (50%) achieved a pCR (breast + nodes). Neutropenia was the most common Grade 3/4 adverse event (57% Grade 3 and 31% Grade 4), but only 1 patient required hospitalisation and IV antibiotics for neutropenic fever. Other Grade 3/4 events included anaemia (24%), thrombocytopenia (29%) and peripheral neuropathy (Grade 3, 5%). Conclusion: Our results demonstrate a substantially higher pCR rate, both in-breast and breast + nodes, with the combination of nab paclitaxel plus carboplatin followed by AC, with concurrent bevacizumab, versus historic pCR rates with anthracycline-taxane regimens alone, supporting further investigation of this regimen, preferably in molecularly driven subsets, for the neoadjuvant treatment of patients with TNBC. Key words: Bevacizumab, breast cancer, carboplatin, nab-paclitaxel, neoadjuvant, triple-negative
SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications
Ground-based observations have insufficient spatial coverage to assess long-term human exposure to fine particulate matter (PM2.5) at the global scale. Satellite remote sensing offers a promising approach to provide information on both short-and long-term exposure to PM2.5 at local-to-global scales, but there are limitations and outstanding questions about the accuracy and precision with which ground-level aerosol mass concentrations can be inferred from satellite remote sensing alone. A key source of uncertainty is the global distribution of the relationship between annual average PM2.5 and discontinuous satellite observations of columnar aerosol optical depth (AOD). We have initiated a global network of ground-level monitoring stations designed to evaluate and enhance satellite remote sensing estimates for application in health-effects research and risk assessment. This Surface PARTiculate mAtter Network (SPARTAN) includes a global federation of ground-level monitors of hourly PM2.5 situated primarily in highly populated regions and collocated with existing ground-based sun photometers that measure AOD. The instruments, a three-wavelength nephelometer and impaction filter sampler for both PM2.5 and PM10, are highly autonomous. Hourly PM2.5 concentrations are inferred from the combination of weighed filters and nephelometer data. Data from existing networks were used to develop and evaluate network sampling characteristics. SPARTAN filters are analyzed for mass, black carbon, water-soluble ions, and metals. These measurements provide, in a variety of regions around the world, the key data required to evaluate and enhance satellite-based PM2.5 estimates used for assessing the health effects of aerosols. Mean PM2.5 concentrations across sites vary by more than 1 order of magnitude. Our initial measurements indicate that the ratio of AOD to ground-level PM2.5 is driven temporally and spatially by the vertical profile in aerosol scattering. Spatially this ratio is also strongly influenced by the mass scattering efficiency.Fil: Snider, G.. Dalhousie University Halifax; CanadáFil: Weagle, C. L.. Dalhousie University Halifax; CanadáFil: Martin, R. V.. Dalhousie University Halifax; Canadá. University of Cambridge; Reino UnidoFil: van Donkelaar, A.. Dalhousie University Halifax; CanadáFil: Conrad, K.. Dalhousie University Halifax; CanadáFil: Cunningham, D.. Dalhousie University Halifax; CanadáFil: Gordon, C.. Dalhousie University Halifax; CanadáFil: Zwicker, M.. Dalhousie University Halifax; CanadáFil: Akoshile, C.. University of Ilorin; NigeriaFil: Artaxo, P.. Governo Do Estado de Sao Paulo; BrasilFil: Anh, N. X.. Vietnam Academy of Science and Technology. Institute of Geophysics; VietnamFil: Brook, J.. University of Toronto; CanadáFil: Dong, J.. Tsinghua University; ChinaFil: Garland, R. M.. North-West University; SudáfricaFil: Greenwald, R.. Rollins School of Public Health; Estados UnidosFil: Griffith, D.. Council for Scientific and Industrial Research; SudáfricaFil: He, K.. Tsinghua University; ChinaFil: Holben, B. N.. NASA Goddard Space Flight Center; Estados UnidosFil: Kahn, R.. NASA Goddard Space Flight Center; Estados UnidosFil: Koren, I.. Weizmann Institute Of Science Israel; IsraelFil: Lagrosas, N.. Manila Observatory, Ateneo de Manila University campus; FilipinasFil: Lestari, P.. Institut Teknologi Bandung; IndonesiaFil: Ma, Z.. Rollins School of Public Health; Estados UnidosFil: Vanderlei Martins, J.. University of Maryland; Estados UnidosFil: Quel, Eduardo Jaime. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rudich, Y.. Weizmann Institute Of Science Israel; IsraelFil: Salam, A.. University Of Dhaka; BangladeshFil: Tripathi, S. N.. Indian Institute Of Technology, Kanpur; IndiaFil: Yu, C.. Rollins School of Public Health; Estados UnidosFil: Zhang, Q.. Tsinghua University; ChinaFil: Zhang, Y.. Tsinghua University; ChinaFil: Brauer, M.. University of British Columbia; CanadáFil: Cohen, A.. Health Effects Institute; Estados UnidosFil: Gibson, M. D.. Dalhousie University Halifax; CanadáFil: Liu, Y.. Rollins School of Public Health; Estados Unido
Motivating Questions and Partial Answers:A Response to Prosecuting Domestic Violence by Michelle Madden Dempse
The Role of Ellis‐Van Creveld 2(EVC2) in Mice During Cranial Bone Development
EvC syndrome is a type of autosomal‐recessive chondrodysplasia. Previous case studies in patients suggest abnormal craniofacial development, in addition to dwarfism and tooth abnormalities. To investigate how craniofacial development is affected in EvC patients, surface models were generated from micro‐CT scans of control mice, Evc2 global mutant mice and Evc2 neural crest‐specific mutant mice. The anatomic landmarks were placed on the surface model to assess the morphological abnormalities in the Evc2 mutants. Through analyzing the linear and angular measurements between landmarks, we identified a smaller overall skull, shorter nasal bone, shorter frontal bone, and shorter cranial base in the Evc2 global mutants. By comparing neural crest‐specific Evc2 mutants with control mice, we demonstrated that the abnormalities within the mid‐facial regions are not accounted for by the Evc2 mutation within these regions. Additionally, we also identified disproportionate length to width ratios in the Evc2 mutants at all levels from anterior to posterior of the skull. Overall, this study demonstrates a more comprehensive analysis on the craniofacial morphological abnormalities in EvC syndrome and provides the developmental insight to appreciate the impact of Evc2 mutation within the neural crest cells on multiple aspects of skull deformities. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:46–55, 2018. © 2017 Wiley Periodicals, Inc.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141635/1/ar23692_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141635/2/ar23692.pd
The source ambiguity problem: Distinguishing the effects of grammar and processing on acceptability judgments
Judgments of linguistic unacceptability may theoretically arise from either grammatical deviance or significant processing difficulty. Acceptability data are thus naturally ambiguous in theories that explicitly distinguish formal and functional constraints. Here, we consider this source ambiguity problem in the context of Superiority effects: the dispreference for ordering a wh-phrase in front of a syntactically “superior” wh-phrase in multiple wh-questions, e.g., What did who buy? More specifically, we consider the acceptability contrast between such examples and so-called D-linked examples, e.g., Which toys did which parents buy? Evidence from acceptability and self-paced reading experiments demonstrates that (i) judgments and processing times for Superiority violations vary in parallel, as determined by the kind of wh-phrases they contain, (ii) judgments increase with exposure, while processing times decrease, (iii) reading times are highly predictive of acceptability judgments for the same items, and (iv) the effects of the complexity of the wh-phrases combine in both acceptability judgments and reading times. This evidence supports the conclusion that D-linking effects are likely reducible to independently motivated cognitive mechanisms whose effects emerge in a wide range of sentence contexts. This in turn suggests that Superiority effects, in general, may owe their character to differential processing difficulty
Digital play and the actualisation of the consumer imagination
In this article, the authors consider emerging consumer practices in digital virtual spaces. Building on constructions of consumer behavior as both a sense-making activity and a resource for the construction of daydreams, as well as anthropological readings of performance, the authors speculate that many performances during digital play are products of consumer fantasy. The authors develop an interpretation of the relationship between the real and the virtual that is better equipped to understand the movement between consumer daydreams and those practices actualized in the material and now also in digital virtual reality. The authors argue that digital virtual performances present opportunities for liminoid transformations through inversions, speculations, and playfulness acted out in aesthetic dramas. To illustrate, the authors consider specific examples of the theatrical productions available to consumers in digital spaces, highlighting the consumer imagination that feeds them, the performances they produce, and the potential for transformation in consumer-players
Quantized charge transport through a static quantum dot using a surface acoustic wave
We present a detailed study of the surface acoustic wave mediated quantized
transport of electrons through a split gate device containing an impurity
potential defined quantum dot within the split gate channel. A new regime of
quantized transport is observed at low RF powers where the surface acoustic
wave amplitude is comparable to the quantum dot charging energy. In this regime
resonant transport through the single-electron dot state occurs which we
interpret as turnstile-like operation in which the traveling wave amplitude
modulates the entrance and exit barriers of the quantum dot in a cyclic fashion
at GHz frequencies. For high RF powers, where the amplitude of the surface
acoustic wave is much larger than the quantum dot energies, the quantized
acoustoelectric current transport shows behavior consistent with previously
reported results. However, in this regime, the number of quantized current
plateaus observed and the plateau widths are determined by the properties of
the quantum dot, demonstrating that the microscopic detail of the potential
landscape in the split gate channel has a profound influence on the quantized
acoustoelectric current transport.Comment: 9 page
Amelioration of bleomycin-induced lung fibrosis in hamsters by dietary supplementation with taurine and niacin: biochemical mechanisms.
Interstitial pulmonary fibrosis induced by intratracheal instillation of bleomycin (BL) involves an excess production of reactive oxygen species, unavailability of adequate levels of NAD and ATP to repair the injured pulmonary epithelium, and an overexuberant lung collagen reactivity followed by deposition of highly cross-linked mature collagen fibrils resistant to enzymatic degradation. In the present study, we have demonstrated that dietary supplementation with taurine and niacin offered almost complete protection against the lung fibrosis in a multidose BL hamster model. The mechanisms for the protective effect of taurine and niacin are multifaceted. These include the ability of taurine to scavenge HOCl and stabilize the biomembrane; niacin's ability to replenish the BL-induced depletion of NAD and ATP; and the combined effect of taurine and niacin to suppress all aspects of BL-induced increases in the lung collagen reactivity, a hallmark of interstitial pulmonary fibrosis. It was concluded from the data presented at this Conference that the combined treatment with taurine and niacin, which offers a multipronged approach, will have great therapeutic potential in the intervention of the development of chemically induced interstitial lung fibrosis in animals and humans
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