1,097 research outputs found
Emergent Phenomena Induced by Spin-Orbit Coupling at Surfaces and Interfaces
Spin-orbit coupling (SOC) describes the relativistic interaction between the
spin and momentum degrees of freedom of electrons, and is central to the rich
phenomena observed in condensed matter systems. In recent years, new phases of
matter have emerged from the interplay between SOC and low dimensionality, such
as chiral spin textures and spin-polarized surface and interface states. These
low-dimensional SOC-based realizations are typically robust and can be
exploited at room temperature. Here we discuss SOC as a means of producing such
fundamentally new physical phenomena in thin films and heterostructures. We put
into context the technological promise of these material classes for developing
spin-based device applications at room temperature
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Biological, clinical and population relevance of 95 loci for blood lipids.
Plasma concentrations of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides are among the most important risk factors for coronary artery disease (CAD) and are targets for therapeutic intervention. We screened the genome for common variants associated with plasma lipids in >100,000 individuals of European ancestry. Here we report 95 significantly associated loci (P < 5 x 10(-8)), with 59 showing genome-wide significant association with lipid traits for the first time. The newly reported associations include single nucleotide polymorphisms (SNPs) near known lipid regulators (for example, CYP7A1, NPC1L1 and SCARB1) as well as in scores of loci not previously implicated in lipoprotein metabolism. The 95 loci contribute not only to normal variation in lipid traits but also to extreme lipid phenotypes and have an impact on lipid traits in three non-European populations (East Asians, South Asians and African Americans). Our results identify several novel loci associated with plasma lipids that are also associated with CAD. Finally, we validated three of the novel genes-GALNT2, PPP1R3B and TTC39B-with experiments in mouse models. Taken together, our findings provide the foundation to develop a broader biological understanding of lipoprotein metabolism and to identify new therapeutic opportunities for the prevention of CAD
Anyonic interferometry and protected memories in atomic spin lattices
Strongly correlated quantum systems can exhibit exotic behavior called
topological order which is characterized by non-local correlations that depend
on the system topology. Such systems can exhibit remarkable phenomena such as
quasi-particles with anyonic statistics and have been proposed as candidates
for naturally fault-tolerant quantum computation. Despite these remarkable
properties, anyons have never been observed in nature directly. Here we
describe how to unambiguously detect and characterize such states in recently
proposed spin lattice realizations using ultra-cold atoms or molecules trapped
in an optical lattice. We propose an experimentally feasible technique to
access non-local degrees of freedom by performing global operations on trapped
spins mediated by an optical cavity mode. We show how to reliably read and
write topologically protected quantum memory using an atomic or photonic qubit.
Furthermore, our technique can be used to probe statistics and dynamics of
anyonic excitations.Comment: 14 pages, 6 figure
Interleukin-17D and Nrf2 mediate initial innate immune cell recruitment and restrict MCMV infection.
Innate immune cells quickly infiltrate the site of pathogen entry and not only stave off infection but also initiate antigen presentation and promote adaptive immunity. The recruitment of innate leukocytes has been well studied in the context of extracellular bacterial and fungal infection but less during viral infections. We have recently shown that the understudied cytokine Interleukin (IL)-17D can mediate neutrophil, natural killer (NK) cell and monocyte infiltration in sterile inflammation and cancer. Herein, we show that early immune cell accumulation at the peritoneal site of infection by mouse cytomegalovirus (MCMV) is mediated by IL-17D. Mice deficient in IL-17D or the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), an inducer of IL-17D, featured an early decreased number of innate immune cells at the point of viral entry and were more susceptible to MCMV infection. Interestingly, we were able to artificially induce innate leukocyte infiltration by applying the Nrf2 activator tert-butylhydroquinone (tBHQ), which rendered mice less susceptible to MCMV infection. Our results implicate the Nrf2/IL-17D axis as a sensor of viral infection and suggest therapeutic benefit in boosting this pathway to promote innate antiviral responses
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Pharmacological Effects of Asiatic acid in Glioblastoma Cells under Hypoxia
Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumor in adults. Despite current treatment options including surgery followed by radiation and chemotherapy with temozolomide (TMZ) and cisplatin, the median survival rate remains low (<16 months). Combined with increasing drug resistance and the inability of some compounds to cross the blood brain barrier (BBB), novel compounds are being sought for the treatment of this disease. Here, we aimed to examine the pharmacological effect of Asiatic acid (AA) in glioblastoma under hypoxia.
To investigate the effects of AA on cell viability, proliferation, apoptosis and wound healing, SVG p12 fetal glia and U87-MG grade IV glioblastoma cells were cultured under normoxic (21% O2) and hypoxic (1% O2) conditions.
In normoxia, AA reduced cell viability in U87-MG cells in a time and concentration-dependent manner. A significant decrease in viability, compared to cisplatin, was observed following 2hrs of AA treatment with no significant changes in cell proliferation or cell cycle progression observed. Under hypoxia, a significantly greater number of cells underwent apoptosis in comparison to cisplatin. While cisplatin showed a reduction in wound healing in normoxia, a significantly greater reduction was observed following AA treatment. An overall reduction in wound healing was observed under hypoxia.
The results of this study show that AA has cytotoxic effects on glioma cell lines and has the potential to become an alternative treatment for glioblastoma
64Cu-ATSM Hypoxia Positron Emission Tomography for Detection of Conduit Ischemia in an Experimental Rat Esophagectomy Model.
BACKGROUND: We designed a hypoxia-imaging modality to detect ischemia of the gastric conduit after esophagectomy.
MATERIALS AND METHODS: A rat esophagectomy model was created using 12-16-week-old, 300-350 g male Sprague-Dawley rats. In the operation group (n=6), partial gastric devascularization was performed by ligating the left gastric artery and the short gastric arteries and an esophagogastric anastomosis was performed. In the control group (n=6), the esophageal-gastric junction was incised and suturing was performed without gastric devascularization. Positron emission tomography (PET) images were taken using a microPET rodent model scanner, 24 h after the initial operation, after injection of 200 μCi 64Cu-diacetyl-bis (N4-methylsemicarbazone) (64Cu-ATSM) and pimonidazole 120 mg/kg. After microPET imaging, autoradiography and immunohistochemistry were performed.
RESULTS: The PET image revealed 64Cu-ATSM uptake at the fundus in the operation group 3 h after 64Cu-ATSM injection. The maximum percentage of the injected dose per gram of tissue was higher in the operation group (0.047±0.015 vs. 0.026±0.006, p=0.021). The fundus/liver ratio was also higher in the operation group (0.541±0.126 vs. 0.278±0.049, p=0.002). Upon autoradiography, 64Cu-ATSM uptake was observed in the fundus in the operation group, and was well-correlated to that observed on the PET image. Upon immunohistochemistry, expression of hypoxia-inducible factor 1a and pimonidazole were significantly increased at the fundus and lesser curvature compared to the greater curvature in the operation group.
CONCLUSION: Hypoxia PET imaging with 64Cu-ATSM can detect ischemia in a rat esophagectomy model. Further clinical studies are needed to verify whether hypoxia imaging may be useful in humans
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Relationship between Environmental Phthalate Exposure and the Intelligence of School-Age Children
BACKGROUND: Concern over phthalates has emerged because of their potential toxicity to humans. OBJECTIVE: We investigated the relationship between the urinary concentrations of phthalate metabolites and children`s intellectual functioning. METHODS: This study enrolled 667 children at nine elementary schools in five South Korean cities. A cross-sectional examination of urine phthalate concentrations was performed, and scores on neuro-psychological tests were obtained from both the children and their mothers. RESULTS: We measured mono-2-ethylhexyl phthalate (MEHP) and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), both metabolites of di(2-ethylhexyl)phthalate (DEHP), and mono-n-butyl phthalate (MBP), a metabolite of dibutyl phthalate (DBP), in urine samples. The geometric mean (ln) concentrations of MEHP, MEOHP, and MBP were 21.3 mu g/L [geometric SD (GSD) = 2.2 mu g/L; range, 0.5-445.4], 18.0 mu g/L (GSD = 2.4; range, 0.07-291.1), and 48.9 mu g/L (GSD = 2.2; range, 2.1-1645.5), respectively. After adjusting for demographic and developmental covariates, the Full Scale IQ and Verbal IQ scores were negatively associated with DEHP metabolites but not with DBP metabolites. We also found a significant negative relationship between the urine concentrations of the metabolites of DEHP and DBP and children`s vocabulary subscores. After controlling for maternal IQ, a significant inverse relationship between DEHP metabolites and vocabulary subscale score remained. Among boys, we found a negative association between increasing MEHP phthalate concentrations and the sum of DEHP metabolite concentrations and Wechsler Intelligence Scale for Children vocabulary score; however, among girls, we found no significant association between these variables. CONCLUSION: Controlling for maternal IQ and other covariates, the results show an inverse relationship between phthalate metabolites and IQ scores; however, given the limitations in cross-sectional epidemiology, prospective studies are needed to fully explore these associations.This work was funded by the Eco-Technopia 21 project of Korea Institute of Environmental Science and Technology (091-081-059).Cho SC, 2010, J CHILD PSYCHOL PSYC, V51, P1050, DOI 10.1111/j.1469-7610.2010.02250.xKim BN, 2009, BIOL PSYCHIAT, V66, P958, DOI 10.1016/j.biopsych.2009.07.034Tanida T, 2009, TOXICOL LETT, V189, P40, DOI 10.1016/j.toxlet.2009.04.005Ghisari M, 2009, TOXICOL LETT, V189, P67, DOI 10.1016/j.toxlet.2009.05.004Barnett JH, 2009, AM J PSYCHIAT, V166, P909, DOI 10.1176/appi.ajp.2009.08081251Kim Y, 2009, NEUROTOXICOLOGY, V30, P564, DOI 10.1016/j.neuro.2009.03.012Engel SM, 2009, NEUROTOXICOLOGY, V30, P522, DOI 10.1016/j.neuro.2009.04.001Kamrin MA, 2009, J TOXICOL ENV HEAL B, V12, P157, DOI 10.1080/10937400902729226Brown JS, 2009, SCHIZOPHRENIA BULL, V35, P256, DOI 10.1093/schbul/sbm147Bellinger DC, 2008, NEUROTOXICOLOGY, V29, P828, DOI 10.1016/j.neuro.2008.04.005Wolff MS, 2008, ENVIRON HEALTH PERSP, V116, P1092, DOI 10.1289/ehp.11007van Neerven S, 2008, PROG NEUROBIOL, V85, P433, DOI 10.1016/j.pneurobio.2008.04.006Hatch EE, 2008, ENVIRON HEALTH-GLOB, V7, DOI 10.1186/1476-069X-7-27Zevalkink J, 2008, J GENET PSYCHOL, V169, P72Kolarik B, 2008, ENVIRON HEALTH PERSP, V116, P98, DOI 10.1289/ehp.10498SATHYANARAYANA S, 2008, CURR PROBL PEDIAT AD, V38, P34KHO YL, 2008, J ENV HLTH SCI, V34, P271Huang PC, 2007, HUM REPROD, V22, P2715, DOI 10.1093/humrep/dem205Janjua NR, 2007, ENVIRON SCI TECHNOL, V41, P5564, DOI 10.1021/es0628755Meeker JD, 2007, ENVIRON HEALTH PERSP, V115, P1029, DOI 10.1289/ehp.9852Fromme H, 2007, INT J HYG ENVIR HEAL, V210, P21, DOI 10.1016/j.ijheh.2006.09.005Xu Y, 2007, ARCH TOXICOL, V81, P57, DOI 10.1007/s00204-006-0143-8Pereira C, 2007, ACTA HISTOCHEM, V109, P29, DOI 10.1016/j.acthis.2006.09.008Hauser R, 2006, EPIDEMIOLOGY, V17, P682, DOI 10.1097/01.ede.0000235996.89953.d7Zhu DF, 2006, BRAIN, V129, P2923, DOI 10.1093/brain/awl215Andrade AJM, 2006, TOXICOLOGY, V227, P185, DOI 10.1016/j.tox.2006.07.022Lottrup G, 2006, INT J ANDROL, V29, P172, DOI 10.1111/j.1365-2605.2005.00642.xBreous E, 2005, MOL CELL ENDOCRINOL, V244, P75, DOI 10.1016/j.mce.2005.06.009Wenzel A, 2005, MOL CELL ENDOCRINOL, V244, P63, DOI 10.1016/j.mce.2005.02.008Kato K, 2005, ANAL CHEM, V77, P2985, DOI 10.1021/ac0481248Tanaka T, 2005, FOOD CHEM TOXICOL, V43, P581, DOI 10.1016/j.fct.2005.01.001Duty SM, 2005, HUM REPROD, V20, P604, DOI 10.1093/humrep/deh656Kota BP, 2005, PHARMACOL RES, V51, P85, DOI 10.1016/j.phrs.2004.07.012Hays T, 2005, CARCINOGENESIS, V26, P219, DOI 10.1093/carcin/bgh285Hauser R, 2004, ENVIRON HEALTH PERSP, V112, P1734, DOI 10.1289/ehp.7212Bornehag CG, 2004, ENVIRON HEALTH PERSP, V112, P1393, DOI 10.1289/ehp.7187Ishido M, 2004, J NEUROCHEM, V91, P69, DOI 10.1111/j.1471-4159.2004.02696.xMink PJ, 2004, EPIDEMIOLOGY, V15, P385, DOI 10.1097/01.ede.0000128402.86336.7eBellinger DC, 2004, EPIDEMIOLOGY, V15, P383, DOI 10.1097/01.ede.0000129525.15064.a4Shea KM, 2003, PEDIATRICS, V111, P1467Tanaka T, 2002, FOOD CHEM TOXICOL, V40, P1499, DOI 10.1016/S0278-6915(02)00073-XHoppin JA, 2002, ENVIRON HEALTH PERSP, V110, P515SATTLER JM, 2001, ASSESSMENT CHILDRENRice D, 2000, ENVIRON HEALTH PERSP, V108, P511Bellinger DC, 2000, NEUROTOXICOL TERATOL, V22, P133LIM YR, 2000, KOR J CLIN PSYCHOL, V19, P563Braissant O, 1998, ENDOCRINOLOGY, V139, P2748Peters JM, 1997, CARCINOGENESIS, V18, P2029Baldini IM, 1997, PROG NEURO-PSYCHOPH, V21, P925Roberts RA, 1997, FUND APPL TOXICOL, V38, P107PARK KS, 1996, DEV KEDI WISC INDIVIMONZANI F, 1993, CLIN INVESTIGATOR, V71, P367SILVERSTEIN AB, 1990, J CLIN PSYCHOL, V46, P333HINTON RH, 1986, ENVIRON HEALTH PERSP, V70, P195KIM MK, 1986, SEOUL J PSYCHIAT, V11, P194KAUFMAN AS, 1976, CONTEMP EDUC PSYCHOL, V1, P1801
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