J/ψ\psi suppression at s=\sqrt{{\bf s}} = 200 GeV in the comovers interaction model

The yield of $J/\psi$ per binary nucleon-nucleon collision in $AuAu$ and $CuCu$ collisions at $\sqrt{s} = 200$ GeV is computed in the framework of the dual parton model, supplemented with final state interaction (comovers interaction). For the latter we use the same value of the cross-section, $\sigma_{co} = 0.65$ mb, which describes the anomalous $J/\psi$ suppression observed at CERN-SPS energies. Several possibilities for the value of the absorptive cross-section are considered. Shadowing is introduced in both the comovers and the $J/\psi$ yields. A comparison with the results at CERN-SPS, including a prediction for $InIn$ collisions, is also presented.Comment: 15 pages, 3 figure

Anomalous suppression of π0\pi^0 production at large transverse momentum in Au + Au and d + Au collisions at sNN=\sqrt{{\bf s}_{\bf NN}} = 200 GeV

We propose a model of suppression of large $p_T$-pions in heavy ion collisions based on the interaction of the large $p_T$ pion with the dense medium created in the collision. The model is practically the same as the one previously introduced to describe $J/\psi$ suppression. Both the $p_T$ and the centrality dependence of the data are reproduced. In deuteron-gold collisions, the effect of the final state interaction with the dense medium turns out to be negligibly small. Here the main features of the data are also reproduced both at mid and at forward rapidities.Comment: 20 pages, latex, 3 postscript figures. Last version, to be published in EJP

Analysis of HIV Diversity in HIV-Infected Black Men Who Have Sex with Men (HPTN 061)

Background HIV populations often diversify in response to selective pressures, such as the immune response and antiretroviral drug use. We analyzed HIV diversity in Black men who have sex with men who were enrolled in the HIV Prevention Trials Network 061 study. Methods A high resolution melting (HRM) diversity assay was used to measure diversity in six regions of the HIV genome: two in gag, one in pol, and three in env. HIV diversity was analyzed for 146 men who were HIV infected at study enrollment, including three with acute infection and 13 with recent infection (identified using a multi-assay algorithm), and for 21 men who seroconverted during the study. HIV diversification was analyzed in a paired analysis for 62 HIV-infected men using plasma samples from the enrollment and 12-month (end of study) visits. Results Men with acute or recent infection at enrollment and seroconverters had lower median HRM scores (lower HIV diversity) than men with non-recent infection in all six regions analyzed. In univariate analyses, younger age, higher CD4 cell count, and HIV drug resistance were associated with lower median HRM scores in multiple regions; ARV drug detection was marginally associated with lower diversity in the pol region. In multivariate analysis, acute or recent infection (all six regions) and HIV drug resistance (both gag regions) were associated with lower median HRM scores. Diversification in the pol region over 12 months was greater for men with acute or recent infection, higher CD4 cell count, and lower HIV viral load at study enrollment. Conclusions HIV diversity was significantly associated with duration of HIV infection, and lower gag diversity was observed in men who had HIV drug resistance. HIV pol diversification was more pronounced in men with acute or recent infection, higher CD4 cell count, and lower HIV viral load

Measurement of D+- and D0 production in deep inelastic scattering using a lifetime tag at HERA

The production of D-+/-- and D-0-mesons has been measured with the ZEUS detector at HERA using an integrated luminosity of 133.6 pb(-1). The measurements cover the kinematic range 5 < Q(2) < 1000 GeV2, 0.02 < y < 0.7, 1.5 < p(T)(D) < 15 GeV and |eta(D)| < 1.6. Combinatorial background to the D-meson signals is reduced by using the ZEUS microvertex detector to reconstruct displaced secondary vertices. Production cross sections are compared with the predictions of next-to-leading-order QCD, which is found to describe the data well. Measurements are extrapolated to the full kinematic phase space in order to obtain the open-charm contribution, F-2(c (c) over bar), to the proton structure function, F-2

Analysis of the Lambda p Final State Interaction in the Reaction p+p->K^+(Lambda p)

The missing mass spectrum measured in high resolution studies of the reaction pp -> K^+X is analyzed with respect to the strong final state interaction near the Lambda p production threshold. The observed spectrum can be described by factorizing the reaction amplitude in terms of a production amplitude and a final state scattering amplitude. Parametrizing the Lambda p final state interaction in terms of the inverse Jost function allows a direct extraction of the low-energy phase-equivalent potential parameters. Constraints on the singlet and triplet scattering lengths and effective ranges are deduced in a simultaneous fit of the Lambda p invariant mass spectrum and the total cross section data of the free Lambda p scattering using the effective range approximation.Comment: 9 pages,6 figures, 2 table

Telemedicine During COVID-19 and Beyond: A Practical Guide and Best Practices Multidisciplinary Approach for the Orthopedic and Neurologic Pain Physical Examination.

BACKGROUND:The COVID pandemic has impacted almost every aspect of human interaction, causing global changes in financial, health care, and social environments for the foreseeable future. More than 1.3 million of the 4 million cases of COVID-19 confirmed globally as of May 2020 have been identified in the United States, testing the capacity and resilience of our hospitals and health care workers. The impacts of the ongoing pandemic, caused by a novel strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have far-reaching implications for the future of our health care system and how we deliver routine care to patients. The adoption of social distancing during this pandemic has demonstrated efficacy in controlling the spread of this virus and has been the only proven means of infection control thus far. Social distancing has prompted hospital closures and the reduction of all non-COVID clinical visits, causing widespread financial despair to many outpatient centers. However, the need to treat patients for non-COVID problems remains important despite this pandemic, as care must continue to be delivered to patients despite their ability or desire to report to outpatient centers for their general care. Our national health care system has realized this need and has incentivized providers to adopt distance-based care in the form of telemedicine and video medicine visits. Many institutions have since incorporated these into their practices without financial penalty because of Medicare\u27s 1135 waiver, which currently reimburses telemedicine at the same rate as evaluation and management codes (E/M Codes). Although the financial burden has been alleviated by this policy, the practitioner remains accountable for providing proper assessment with this new modality of health care delivery. This is a challenge for most physicians, so our team of national experts has created a reference guide for musculoskeletal and neurologic examination selection to retrofit into the telemedicine experience. OBJECTIVES:To describe and illustrate musculoskeletal and neurologic examination techniques that can be used effectively in telemedicine. STUDY DESIGN:Consensus-based multispecialty guidelines. SETTING:Tertiary care center. METHODS:Literature review of the neck, shoulder, elbow, wrist, hand, lumbar, hip, and knee physical examinations were performed. A multidisciplinary team comprised of physical medicine and rehabilitation, orthopedics, rheumatology, neurology, and anesthesia experts evaluated each examination and provided consensus opinion to select the examinations most appropriate for telemedicine evaluation. The team also provided consensus opinion on how to modify some examinations to incorporate into a nonhealth care office setting. RESULTS:Sixty-nine examinations were selected by the consensus team. Household objects were identified that modified standard and validated examinations, which could facilitate the examinations.The consensus review team did not believe that the modified tests altered the validity of the standardized tests. LIMITATIONS:Examinations selected are not validated for telemedicine. Qualitative and quantitative analyses were not performed. CONCLUSIONS:The physical examination is an essential component for sound clinical judgment and patient care planning. The physical examinations described in this manuscript provide a comprehensive framework for the musculoskeletal and neurologic examination, which has been vetted by a committee of national experts for incorporation into the telemedicine evaluation

Two-dimensional X-ray diffraction as a tool for the rapid, non-destructive detection of low calcite quantities in aragonitic corals

Paleoclimate reconstructions based on reef corals require precise detection of diagenetic alteration. Secondary calcite can significantly affect paleotemperature reconstructions at very low amounts of ~1%. X-ray powder diffraction is routinely used to detect diagenetic calcite in aragonitic corals. This procedure has its limitations as single powder samples might not represent the entire coral heterogeneity. A conventional and a 2-D X-ray diffractometer were calibrated with gravimetric powder standards of high and low magnesium calcite (0.3% to 25% calcite). Calcite contents <1% can be recognized with both diffractometer setups based on the peak area of the calcite [104] reflection. An advantage of 2-D-XRD over convenient 1-D-XRD methods is the nondestructive and rapid detection of calcite with relatively high spatial resolution directly on coral slabs. The calcite detection performance of the 2-D-XRD setup was tested on thin sections from fossil Porites sp. samples that, based on powder XRD measurements, showed <1% calcite. Quantification of calcite contents for these thin sections based on 2-D-XRD and digital image analysis showed very similar results. This enables spot measurements with diameters of ∼4 mm, as well as systematic line scans along potential tracks previous to geochemical proxy sampling. In this way, areas affected by diagenetic calcite can be avoided and alternative sampling tracks can be defined. Alternatively, individual sampling positions that show dubious proxy results can later be checked for the presence of calcite. The presented calibration and quantification method can be transferred to any 2-D X-ray diffractometer