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The conductivity of single layer and bilayer graphene ribbons 0.5–4 μm in width fabricated by oxygen plasma etching is studied experimentally. The dependence of the electron concentration in graphene on the ribbon width is revealed. This effect is explained by the edge doping of graphene due to defects arranged in SiO2 near the ribbon edges. The method of the formation of abrupt p–n junctions in graphene and structures with a constant electron concentration gradient in the graphene plane with the help of edge doping is proposed.

Aging is a factor associated with poor prognosis in glioblastoma (GBM). It is therefore important to understand the molecular features of aging contributing to GBM morbidity. TP73-AS1 is a long noncoding RNA (lncRNA) over expressed in GBM tumors shown to promote resistance to the chemotherapeutic temozolomide (TMZ), and tumor aggressiveness. How the expression of TP73-AS1 is regulated is not known, nor is it known if its expression is associated with aging. By analyzing transcriptional data obtained from natural and pathological aging brain, we found that the expression of TP73-AS1 is high in pathological and naturally aging brains. YY1 physically associates with the promoter of TP73-AS1 and we found that along with TP73-AS1, YY1 is induced by TMZ. We found that the TP73-AS1 promoter is activated by TMZ, and by YY1 over expression. Using CRISPRi to deplete YY1, we found that YY1 promotes up regulation of TP73-AS1 and the activation of its promoter during TMZ treatment. In addition, we identified two putative YY1 binding sites within the TP73-AS1 promoter, and used mutagenesis to find that they are essential for TMZ mediated promoter activation. Together, our data positions YY1 as an important TP73-AS1 regulator, demonstrating that TP73-AS1 is expressed in the natural and pathological aging brain, including during neurodegeneration and cancer. Our findings advance our understanding of TP73-AS1 expression, bringing forth a new link between TMZ resistance and aging, both of which contribute to GBM morbidity.

We present STAR measurements of strange hadron (KS0, Λ, Λ¯, Ξ−, Ξ¯+, Ω−, Ω¯+, and ϕ) production at midrapidity (|y

Scikit-HEP is a community-driven and community-oriented project with the goal of providing an ecosystem for particle physics data analysis in Python. Scikit-HEP is a toolset of approximately twenty packages and a few "affiliated" packages. It expands the typical Python data analysis tools for particle physicists. Each package focuses on a particular topic, and interacts with other packages in the toolset, where appropriate. Most of the packages are easy to install in many environments; much work has been done this year to provide binary "wheels" on PyPI and conda-forge packages. The Scikit-HEP project has been gaining interest and momentum, by building a user and developer community engaging collaboration across experiments. Some of the packages are being used by other communities, including the astroparticle physics community. An overview of the overall project and toolset will be presented, as well as a vision for development and sustainability., Comment: 6 pages, 3 figures, Proceedings of the 24th International Conference on Computing in High Energy and Nuclear Physics (CHEP 2019), Adelaide, Australia, 4-8 November 2019

We report new STAR measurements of the single-spin asymmetries $A_L$ for $W^+$ and $W^-$ bosons produced in polarized proton--proton collisions at $\sqrt{s}$ = 510 GeV as a function of the decay-positron and decay-electron pseudorapidity. The data were obtained in 2013 and correspond to an integrated luminosity of 250 pb$^{-1}$. The results are combined with previous results obtained with 86 pb$^{-1}$. A comparison with theoretical expectations based on polarized lepton-nucleon deep-inelastic scattering and prior polarized proton--proton data suggests a difference between the $\bar{u}$ and $\bar{d}$ quark helicity distributions for $0.05 < x < 0.25$. In addition, we report new results for the double-spin asymmetries $A_{LL}$ for $W^\pm$, as well as $A_L$ for $Z/\gamma^*$ production and subsequent decay into electron--positron pairs.

The azimuthal anisotropic flow of identified and unidentified charged particles has been systematically studied in Cu+Au collisions at sNN=200 GeV for harmonics n=1–4 in the pseudorapidity range |η

Infection is the most common cause of mortality in early life, and immunization is the most promising biomedical intervention to reduce this burden. However, newborns fail to respond optimally to most vaccines. Adjuvantation is a key approach to enhancing vaccine immunogenicity, but responses of human newborn leukocytes to most candidate adjuvants, including most TLR agonists, are functionally distinct. Herein, we demonstrate that 3M-052 is a locally acting lipidated imidazoquinoline TLR7/8 agonist adjuvant in mice, which, when properly formulated, can induce robust Th1 cytokine production by human newborn leukocytes in vitro, both alone and in synergy with the alum-adjuvanted pneumococcal conjugate vaccine 13 (PCV13). When admixed with PCV13 and administered i.m. on the first day of life to rhesus macaques, 3M-052 dramatically enhanced generation of Th1 CRM-197-specific neonatal CD4+ cells, activation of newborn and infant Streptococcus pneumoniae polysaccharide-specific (PnPS-specific) B cells as well as serotype-specific antibody titers, and opsonophagocytic killing. Remarkably, a single dose at birth of PCV13 plus 0.1 mg/kg 3M-052 induced PnPS-specific IgG responses that were approximately 10-100 times greater than a single birth dose of PCV13 alone, rapidly exceeding the serologic correlate of protection, as early as 28 days of life. This potent immunization strategy, potentially effective with one birth dose, could represent a new paradigm in early life vaccine development.

We report a nonsaturating linear magnetoresistance in charge-compensated bilayer graphene in a temperature range from 1.5 to 150 K. The observed linear magnetoresistance disappears away from charge neutrality, ruling out the traditional explanation of the effect in terms of the classical random resistor network model. We show that experimental results qualitatively agree with a phenomenological two-fluid model taking into account electron-hole recombination and finite-size sample geometry. © 2016 American Physical Society.

A primary goal of the high luminosity era at RHIC will be the study of heavy quark behavior in Quark Gluon Plasma. The integration of high precision silicon-based tracking in the form of the Heavy Flavor Tracker for the STAR Experiment should enable the reconstruction and identification of charmed hadron decays, working in concert with STAR’s Time Projection Chamber to determine momenta and displacement of decay daughters from the primary collision vertex. To reach the precision demands, the new detectors must be calibrated and sufficiently accounted in tracking to observe charmed hadrons with high signal-to-noise. In this paper we will review the STAR Collaboration’s developments and achievements in this critical effort.

Rationale: Edema fluid resorption is critical for gas exchange and requires active epithelial ion transport by Na,K-ATPase and other ion transport proteins. Objectives: In this study, we sought to determine if alveolar fluid clearance (AFC) is stimulated by 3,3′,5 triiodo-l-thyronine (T3). Methods: AFC was measured in in situ ventilated lungs and ex vivo isolated lungs by instilling isosmolar 5% bovine serum albumin solution with fluorescein-labeled albumin tracer and measuring the change in fluorescein isothiocyanate–albumin concentration over time. Measurements and Main Results: Systemic treatment with intraperitoneal injections of T3 for 3 consecutive days increased AFC by 52.7% compared with phosphate-buffered saline-injected control rats. Membranes prepared from alveolar epithelial cells from T3-treated rats had higher Na,K-ATPase hydrolytic activity. T3 (10−6 M), but not reverse T3 (3,3′,5′ triiodo-l-thyronine), applied to the alveolar space increased AFC by 31.8% within 1.5 hours. A 61.5% increase in AFC also occurred by airspace instillation of T3 in ex vivo isolated lungs, suggesting a direct effect of T3 on the alveolar epithelium. Exposure of rats to an oxygen concentration of greater than 95% for 60 hours increased wet-to-dry lung weights and decreased AFC, whereas the expression of thyroid receptor was not markedly changed. Airspace T3 rapidly restored the AFC in rat lungs with hyperoxia-induced lung injury. Conclusions: Airspace T3 rapidly stimulates AFC by direct effects on the alveolar epithelium in rat lungs with and without lung injury.

Natriuretic peptide receptor A (NPR-A) and natriuretic peptide receptor B (NPR-B) are transmembrane guanylyl cyclases that catalyze the synthesis of cGMP in response to natriuretic peptides. Phosphorylation and dephosphorylation regulate these receptors and have been traditionally studied by (32)PO(4) labeling of transfected cells. However, this approach cannot be used to determine the phosphorylation state of receptors isolated from unlabeled sources. Here, we use Pro-Q Diamond and SYPRO Ruby dyes to quantify the phosphorylation status and protein levels, respectively, of natriuretic peptide receptors from tissues and cells. Strong Pro-Q Diamond signals for NPR-A and NPR-B were obtained when receptors were isolated from lung tissue, liver tissue and overexpressing cells. The level of NPR-A Pro-Q staining was also high in kidney but was much lower in heart tissue. In contrast, the SYPRO Ruby protein signal was weaker and more variable. In a direct comparison, Pro-Q Diamond staining was as sensitive as but more specific than the (32)PO(4) labeling method. The two approaches were highly correlated (R(2) = 0.98). We exploited these techniques to measure the effect of cGMP-dependent protein kinase Ialpha on the phosphate content and guanylyl cyclase activity of NPR-A. Neither value was significantly affected in cells overexpressing cGK-Ialpha or in tissues from mice lacking cGK-I. We conclude that cGK-I does not regulate the cyclase activity or phosphorylation state of NPR-A. Furthermore, we find that Pro-Q Diamond staining is a sensitive method for measuring the phosphate levels of natriuretic peptide receptors, but protein levels are best detected by Western blot analysis, not SYPRO Ruby staining.

The electronic properties of bilayer graphene strongly depend on relative orientation of the two atomic lattices. Whereas Bernal-stacked graphene is most commonly studied, a rotational mismatch between layers opens up a whole new field of rich physics, especially at small interlayer twist. Here we report on magnetotransport measurements on twisted graphene bilayers, prepared by folding of single layers. These reveal a strong dependence on the twist angle, which can be estimated by means of sample geometry. At small rotation, superlattices with a wavelength in the order of 10 nm arise and are observed by friction atomic force microscopy. Magnetotransport measurements in this small-angle regime show the formation of satellite Landau fans. These are attributed to additional Dirac singularities in the band structure and discussed with respect to the wide range of interlayer coupling models., The properties of bilayer graphene can be tuned by twisting the layers relative to one another. Schmidt et al. now demonstrate the twist angle dependence of magnetotransport in this material system and uncover the formation of satellite Landau fans in the small-angle regime because of superlattice formation

C-type natriuretic peptide (CNP) activation of the guanylyl cyclase-linked natriuretic peptide receptor-B (NPR-B) stimulates vasorelaxation and bone growth. Hormones and phorbol esters (PMA) inhibit NPR-B in calcium and protein kinase c-dependent manners, respectively. Here, we characterize the kinetic properties of NPR-B in membranes from cells exposed to PMA, the calcium ionophore, ionomycin, or sphingosine-1-phosphate (S1P). PMA and ionomycin primarily increased the K(m) and decreased the V(max) of NPR-B for GTP, respectively, whereas S1P caused modest changes in both parameters. PMA and S1P treatment increased the EC50 for CNP activation by eight- and three-fold, whereas ionomycin was ineffective. All three agents caused NPR-B dephosphorylation, but the basis for the loss of phosphate differed between treatments. In vitro phosphorylation of NPR-B in membranes was markedly diminished by prior whole cell PMA or S1P exposure, whereas ionomycin pretreatment had no effect. The involvement of the known phosphorylated residues in each process was tested with a mutant receptor containing glutamates substituted for these sites. While the effect of PMA was lost on this receptor, the effects of S1P and ionomycin were only partially blocked. Our data suggest that the molecular bases for PMA- and calcium-dependent inhibition of NPR-B are unique. The former results from reduced phosphorylation of a known site and primarily affects the affinity of NPR-B for CNP and GTP. The latter is associated with reductions in maximal velocities by a mechanism that does not involve inhibition of NPR-B phosphorylation and requires a process in addition to the dephosphorylation of the known sites.

The Second Violin Sonata for violin and piano (1968), subtided Quasi una Sonata, is one of Alfred Schnittke's most popular works, and it is one of my personal favourites among his pieces (alongside his First Symphony, First String Quartet, First Hymn, Second and Third Violin Concerti, Three Madrigals, etc). I discovered Schnittke's music in April 1969 at an underground concert given in the Gnessin Institute in Moscow by Alexei Lyubimov (piano), Boris Berman (piano), Lev Mikhailov (clarinet) and a few string players. This half-forbidden concert, organized by Alexander Ivashkin, was all that remained of a whole festival, which had been cancelled at the last moment by the authorities. The concert was split into three parts, the first two of them dedicated to the music of the Soviet avant-garde, with compositions by the likes of Edison Denisov, Tigran Mansurian, Valentin Silvestrov, Viktor Ekimovsky and Kuldar Sink etc. At the end of the second part there was a perfonnance of Schnittke's Serenade for five musicians. This very cheerful and fanny piece, entangled with hundreds of short quotations, sounded very different from the rest of the program. The final part of the concert contained works of Schoenberg, Berg and Webern, played for the first time in Brezhnev's Soviet Union.

The reconstruction and identification of charmed hadron decays provides an important tool for the study of heavy quark behavior in the Quark Gluon Plasma. Such measurements require high resolution to topologically identify decay daughters at vertices displaced < 100 microns from the primary collision vertex, placing stringent demands on track reconstruction software. To enable these measurements at RHIC, the STAR experiment has designed and employed the Heavy Flavor Tracker (HFT). It is composed of silicon-based tracking detectors, providing four layers of high-precision position measurements which are used in combination with hits from the Time Projection Chamber (TPC) to reconstruct track candidates. The STAR integrated tracking software (Sti) has delivered a decade of world-class physics. It was designed to leverage the discrete azimuthal symmetry of the detector and its simple radial ordering of components, permitting a flat representation of the detector geometry in terms of concentric cylinders and planes, and an approximate track propagation code. These design choices reflected a careful balancing of competing priorities, trading precision for speed in track reconstruction. To simplify the task of integrating new detectors, tools were developed to automatically generate the Sti geometry model, tying both reconstruction and simulation to the single source AgML geometry model. The increased precision and complexity of the HFT detector required a careful reassessment of this single geometry path and implementation choices. In this paper we will discuss the test suite and regression tools developed to improve reconstruction with the HFT, our lessons learned in tracking with high precision detectors and the tradeoffs between precision, speed and ease of use which were required.

Twisted Bilayer Graphene may be viewed as very first representative of the now booming class of artificially layered 2D materials. Consisting of two sheets from the same structure and atomic composition, its decisive degree of freedom lies in the rotation between crystallographic axes in the individual graphene monolayers. Geometrical consideration finds angle-dependent Moire patterns as well as commensurate superlattices of opposite sublattice exchange symmetry. Beyond the approach of rigidly interposed lattices, this review takes focus on the evolving topic of lattice corrugation and distortion in response to spatially varying lattice registry. The experimental approach to twisted bilayers requires a basic control over preparation techniques; important methods are summarized and extended on in the case of bilayers folded from monolayer graphene via AFM nanomachining. Central morphological parameters to the twisted bilayer, rotational mismatch and interlayer separation are studied in a broader base of samples. Finally, experimental evidence for a number of theoretically predicted, controversial electronic scenarios are reviewed; magnetotransport signatures are discussed in terms of Fermi velocity, van Hove singularities and Berry phase and assessed with respect to the underlying experimental conditions, thereby referring back to the initially considered variations in relaxed lattice structure.

δ-Opioid receptor (DOR) promoter exhibited a cell-type–specific expression pattern. Protein-DNA interactions in this promoter were identified by dimethyl sulfate in vivo footprinting analysis of NG108-15 cells, expressing endogenous DOR. Complete protection of the putative Sp1 cis -element and partial protection of the sequence defined as X- Not I in the basal promoter were observed only in the G/G1 phase of the cell cycle. No protection was detected in Neuro2A cells that do not express DOR. In vivo formaldehyde cross-linking confirmed Sp1 factor binding to its cis -acting element during the G/G1 phase. The functional significance of these Sp1 and X- Not I sites was evaluated by transient transfection analysis. Northern blot analysis and nuclear run-off assays revealed maximum DOR mRNA level and transcription rate, respectively, during the G/G1 phase of NG108-15 cells. In summary, the protein-DNA interactions at the Sp1 and X- Not I sites are necessary for cell cycle-dependent and cell-type–specific up-regulated DOR gene expression.

Previously, we reported the presence of dual promoters, referred to as distal (DP) and proximal, with a negative regulatory element between them in the mouse mu-opioid receptor (mor) gene. Here we have identified a positive regulatory element influencing mor DP transcription, which contains multiple consensus binding motifs for Sox factors (sex-determining Sry-like high mobility group box-containing genes). In gel supershift assays, the Sox family member Sox18 bound directly to the multiple Sox consensus binding motifs of the mor DP enhancer. Overexpression of Sox18 cDNA increased luciferase activity regulated by the mor DP, and did so in a Sox18 concentration-dependent manner. In contrast, overexpression of another Sox member, Sox5, triggered no such trans-activation of mor DP-driven luciferase activity or DNA-protein binding activity. These results suggest that Sox18 directly and specifically stimulates mor gene expression, by trans-activating the mor DP enhancer.

An Atomic Force Microscope is used to locally manipulate a single layer graphene sheet. Transport measurements in this region as well as in the unmanipulated part reveal different charge carrier densities while mobilities stay in the order of 10000 cm^2/(Vs). With a global backgate, the system is tuned from a unipolar n-n' or p-p' junction with different densities to a bipolar p-n junction. Magnetotransport across this junction verifies its nature, showing the expected quantized resistance values as well as the switching with the polarity of the magnetic field. The mixing of edge states at the p-n junction is shown to be supressed at high magnetic fields., 4 pages, 3 figures

The electronic dispersion of a graphene bilayer is highly dependent on rotational mismatch between layers and can be further manipulated by electrical gating. This allows for an unprecedented control over electronic properties and opens up the possibility of flexible band structure engineering. Here we present novel magnetotransport data in a twisted bilayer, crossing the energetic border between decoupled monolayers and coupled bilayer. In addition a transition in Berry phase between pi and 2pi is observed at intermediate magnetic fields. Analysis of Fermi velocities and gate induced charge carrier densities suggests an important role of strong layer asymmetry for the observed phenomena., Comment: 20 pages main paper + 10 pages supporting information

Aharonov-Bohm oscillations are observed in a graphene quantum ring with a top gate covering one arm of the ring. As graphene is a gapless semiconductor this geometry allows to study not only the quantum interference of electrons with electrons or holes with holes but also the unique situation of quantum interference between electrons and holes. The period and amplitude of the observed Aharonov-Bohm oscillations are independent of the sign of the applied gate voltage showing the equivalence between unipolar and dipolar interference., Comment: 4 pages, 3 figures

Thymine starvation results in a terminal cellular condition known as thymineless death (TLD), which is the basis of action for several common antibiotics and anticancer drugs. We characterized the onset and progression of TLD in Escherichia coli and found that DNA damage is the only salient property that distinguishes cells irreversibly senesced under thymine starvation from cells reversibly arrested by the nucleotide limitation. The damage is manifested as the relative loss of genetic material spreading outward from the replication origin: the extent of TLD correlates with the progression of damage. The reduced lethality in mutants deficient in the RecFOR/JQ repair pathway also correlates with the extent of damage, which explains most of the observed variance in cell killing. We propose that such spatially localized and persistent DNA damage is the consequence of transcription-dependent initiation of replication in the thymine-starved cells and may be the underlying cause of TLD.

more or less clandestinely, becoming afocus of inspirationfor successive generations of Russian composers, including many who are now recognized as the leaders of contemporary music in the USSR. Among the closest to Herschkowitz was Dmitri Smimov, who has written a so-far unpublished book on his relations with this 'skeletonkeyfigure' in the history of modern Soviet music, and who wrote the Jollowing article at the special request ofTempo. For such an elusive person, the scattered references to Herschkowitz have rendered his name in a surprisingly large variety of spellings: the Editor of Tempo has seen it quoted as Hertzkovitch, Herskovits, Herscovici and Hercovic in addition to its invariable form in Russia, 'Gershkovich'. Although several of our contributors have used the forms Philip and Gershkovich in their original copy, we have decidedfor reasons of consistency to use the Austro-Germanform 'Herschkowitz'by which Webem undoubtedly knew him in Vienna, the city where lie died last year. Mr. Smirov's article has been translated and edited by Rosamund Bartlett.)

According to the Standard Model, the top quark decays to a W boson and a b quark virtually 100% of the time. The measurements of tt¯ production cross section depend strongly on that assumption. We test this hypothesis with a measurement of R = B(t → W b)/B(t → Wq), using a combination of event kinematics and b- tagging techniques. The measurement is carried out using a data sample produced in pp¯ collisions at 1.96 TeV and collected at the Collider Detector at Fermilab between March 2002 and September 2003 with an integrated luminosity of ∼ 162 pb−1. The branching ratio R is determined from the relative tt¯ tagging rates making the measurement independent of any assumption on the tt¯ cross section. Any two tagging rates are sufficient to determine the R but the problem is overconstrained if more than two tagged subsamples are used. The tt¯ events are classified by the number vii of leptons in the final state. In lepton-plus-jets channel only one of the W bosons decays leptonically, whereas in dilepton channel both W bosons decay leptonically. The measurement of R is performed in both lepton-plus-jets and dilepton samples. In the lepton-plus-jets channel the background is estimated using the artificial neural network (ANN) technique. The ANN approach allows us to measure the signal fraction in samples with any number of tags. By applying this method alone the branching ratio was measured to be R = 1.06+0.27(stat.) ± 0.16(syst.). Alternatively, the tagged background contamination in lepton-plus-jets channel is determined from a traditional a priori method using data driven and Monte Carlo based techniques. A similar approach is used to determine the tt¯ content in the dilepton sample. The combination of ANN background measurement in lepton-plus- jets data sample with the a priori lepton-plus-jets and dilepton estimations leads to improved sensitivity in the final value of R = 1.12+0.21(stat.)+0.17(syst.). −0.19 −0.13 Finally, we construct the confidence level bands based on the method proposed by Feldman and Cousins. From these bands and our final measurement of R we set the lower limit of R > 0.61 at 95% confidence level.

The influence of high magnetic fields on coherent transport is investigated. A monolayer graphene quantum ring is fabricated and the Aharonov-Bohm effect is observed. For increased magnitude of the magnetic field, higher harmonics appear. This phenomenon is attributed to an increase of the phase coherence length due to reduction of spin flip scattering. © 2014 AIP Publishing LLC.

Meeting abstracts TLR agonists have demonstrated anti-tumor activity in both animals and humans. Clinically, successful anti-tumor activity with TLR agonists was most often observed when the molecules were applied locally to dermatological cancers. This mode of administration was also associated

Background The TLR7/8 agonist 3M-052 and the TLR9 agonist CpG ODN both trigger innate immune responses that support the induction of tumor-specific immunity. Previous studies showed that these agonists used individually could improve the survival of mice challenged with small tumors but were of limited therapeutic benefit against large/advanced tumors. Methods Normal mice were challenged with syngeneic tumors. Once these tumors reached clinically detectable size (500–800 mm3) they were treated by intra-tumoral injection with 3M-052 and/or CpG ODN. Anti-tumor immunity and tumor growth were evaluated. Results The co-delivery of agonists targeting TLRs 7, 8 and 9 increased the number and tumoricidal activity of tumor infiltrating CTL and NK cells while reducing the frequency of immunosuppressive MDSC. The combination of 3M-052 plus CpG ODN (but not each agent alone) eradicated large primary tumors and established long-term protective immunity. Conclusion The combination of agonists targeting TLRs 7/8 and 9 represents a significant improvement in cancer immunotherapy.