Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at sqrt[s]=13  TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Δη|<1.8 and a transverse momentum of 1 Collapse

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First Measurement of the |t| Dependence of Incoherent J/ψ Photonuclear Production

The first measurement of the cross section for incoherent photonuclear production of J/ψ vector mesons as a function of the Mandelstam |t| variable is presented. The measurement was carried out with the ALICE detector at midrapidity, |y|<0.8, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. This rapidity interval corresponds to a Bjorken-x range (0.3-1.4)×10^{-3}. Cross sections are given in five |t| intervals in the range 0.04<|t|<1  GeV^{2} and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a |t| dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.

ψ(2S) Suppression in Pb-Pb Collisions at the LHC

The production of the ψ(2S) charmonium state was measured with ALICE in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity (2.5 Collapse

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Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13  TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30  GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

Quantitative mapping of strain and displacement fields over HR-TEM and HR-STEM images of crystals with reference to a virtual lattice

A method for the reciprocal space treatment of high-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning transmission electron microscopy (HR-STEM) images has been developed. Named "Absolute strain" (AbStrain), it allows for quantification and mapping of interplanar distances and angles, displacement fields and strain tensor components with reference to a user-defined Bravais lattice and with their corrections from the image distortions specific to HR-TEM and HR-STEM imaging. We provide the corresponding mathematical formalism. AbStrain goes beyond the restriction of the existing method known as geometric phase analysis by enabling direct analysis of the area of interest without the need for reference lattice fringes of a similar crystal structure on the same field of view. In addition, for the case of a crystal composed of two or more types of atoms, each with its own sub-structure constraint, we developed a method named "Relative displacement" for extracting sub-lattice fringes associated to one type of atom and measuring atomic columns displacements associated to each sub-structure with reference to a Bravais lattice or to another sub-structure. The successful application of AbStrain and Relative displacement to HR-STEM images of functional oxide ferroelectric heterostructures is demonstrated.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

Measurement of the J/ψ Polarization with Respect to the Event Plane in Pb-Pb Collisions at the LHC

We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in the rapidity region 2.5 Collapse

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First Measurement of Antideuteron Number Fluctuations at Energies Available at the Large Hadron Collider

The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|η|<0.8) as a function of collision centrality in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.

Enhanced Deuteron Coalescence Probability in Jets

The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13  TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5  GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the B_{2}^{Jet} is not reproduced by the models, which instead give a decreasing trend.

Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over →]+p[over →] Collisions

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510  GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510  GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02<x<0.08, with direct sensitivity to the sign of the gluon contribution.

Low global frontal brain activity is associated with non-planned or impulsive suicide attempts. A preliminary study

BACKGROUND

Suicide prevention is limited by the frequent non-planned or impulsive nature of suicidal behavior. For instance, 25-62 % of suicide attempts, occur within 30 min of the onset of suicidal ideation. We aimed to examine frontal brain activity in depressed patients following a suicide attempt and its relationship with the duration of the suicidal process.

METHODS

We recruited 35 adult patients within three days of a suicide attempt of at least moderate lethality. Duration of the suicidal process was recorded in a semi-structured interview, including suicide contemplation (time from onset of suicidal ideation to decision to kill oneself) and suicide action intervals (time from the decision to kill oneself to suicide attempt). Resting state EEG data from AF7, AF8, TP9 and TP10 leads was collected with a portable MUSE 2 headband system. The average frequency values throughout a 5-minute portable EEG recording were extracted for delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), and beta (13-30 Hz) waves.

RESULTS

Delta (r = 0.450, p = 0.021) and theta power (r = 0.395, p = 0.044) were positively correlated with the duration of the suicide action interval. There were no significant correlations of the suicide contemplation interval with clinical or EEG measures. Patients with suicide action interval shorter than 30 min showed lower delta power (U = 113, p = 0.049) compared with those with longer duration.

CONCLUSIONS

Lower theta and delta activity may reflect hindered cognitive control and inhibition in impulsive suicide attempters. Portable EEG may provide a valuable tool for clinical research and in the management of acutely suicidal patients.

Improved Blood Suppression of Motion-Sensitized Driven Equilibrium in High-Resolution Whole-Brain Vessel Wall Imaging: Comparison of Contrast-Enhanced 3D T1-Weighted FSE with Motion-Sensitized Driven Equilibrium and Delay Alternating with Nutation for Tailored Excitation

BACKGROUND AND PURPOSE

High-resolution vessel wall MR imaging is prone to slow-flow artifacts, particularly when gadolinium shortens the T1 relaxation time of blood. This study aimed to determine the optimal preparation pulses for contrast-enhanced high-resolution vessel wall MR imaging.

MATERIALS AND METHODS

Fifty patients who underwent both motion-sensitized driven equilibrium and delay alternating with nutation for tailored excitation (DANTE) preparation pulses with contrast-enhanced 3D-T1-FSE were retrospectively included. Qualitative analysis was performed using a 4-grade visual scoring system for black-blood performance in the small-sized intracranial vessels, overall image quality, severity of artifacts, and the degree of blood suppression in all cortical veins as well as transverse sinuses. Quantitative analysis of the M1 segment of the MCA was also performed.

RESULTS

The qualitative analysis revealed that motion-sensitized driven equilibrium demonstrated a significantly higher black-blood score than DANTE in contrast-enhanced 3D-T1-FSE of the A3 segment (3.90 versus 3.58, P < .001); M3 (3.72 versus 3.26, P = .004); P2 to P3 (3.86 versus 3.64, P = .017); the internal cerebral vein (3.72 versus 2.32, P < .001); and overall cortical veins (3.30 versus 2.74, P < .001); and transverse sinuses (2.82 versus 2.38, P < .001). SNR_lumen, contrast-to noise ratio_wall-lumen, and SNR_wall in the M1 vessel were not significantly different between the 2 preparation pulses (all, P > .05).

CONCLUSIONS

Motion-sensitized driven equilibrium demonstrated improved blood suppression on contrast-enhanced 3D-T1-FSE in the small intracranial arteries and veins compared with DANTE. Motion-sensitized driven equilibrium is a useful preparation pulse for high-resolution vessel wall MR imaging to decrease venous contamination and suppress slow-flow artifacts when using contrast enhancement.

In Vitro Analysis of the Efficacy of Endovascular Thrombectomy Techniques according to the Vascular Tortuosity Using 3D Printed Models

BACKGROUND AND PURPOSE

Achieving complete recanalization with the front-line endovascular thrombectomy device improves the outcome of acute stroke. The aim of this study was to evaluate whether various thrombectomy techniques including contact aspiration, stent retriever thrombectomy, and combination therapy differ in first-pass effect and distal emboli in acute large-vessel occlusion simulated using 3D printed nontortuous and tortuous cerebrovascular anatomy models.

MATERIALS AND METHODS

3D printed flow models were manufactured using angiographic data of nontortuous and acutely angulated tortuous vascular anatomy from real patients. Three thrombectomy techniques, contact aspiration, stent retriever, and combined methods, were tested under proximal protection with the balloon-guiding catheter. The first-pass effect and distal emboli rates were analyzed in addition to the thrombectomy-failure mechanisms of the respective techniques.

RESULTS

A total of 30 thrombectomy experiments were performed. The overall incidence of first-pass effect in the nontortuous and tortuous anatomy was 80.0% versus 46.7%. The overall incidence of distal emboli in the nontortuous and tortuous anatomy was 26.7% versus 46.7%. The contact aspiration technique showed better first-pass effect (80.0%) and distal emboli rates (20%) in the tortuous model compared with other techniques. The combined technique did not show remarkable superiority of the first-pass effect and distal emboli in either the nontortuous or tortuous anatomy. Shearing off of the thrombus was the main mechanism of thrombectomy failure in the combined group.

CONCLUSIONS

The tortuous vascular anatomy may worsen the first-pass effect and distal emboli rates. The combined techniques failed to show improvement in outcome due to the shearing-off phenomenon of the thrombus during retrieval.

The Experience of Pain is Strongly Associated With Poor Sleep Quality and Increased Risk for Suicide

OBJECTIVE

Effective suicide prevention is hindered by a limited understanding of the neurobiology leading to suicide. We aimed to examine the association between changes in the experience of pain and disturbances in sleep quantity and quality in patients with elevated risk for suicide.

METHODS

Three groups of adult depressed individuals, including patients following a recent suicide attempt (n = 79), patients experiencing current suicidal ideation (n = 131), and patients experiencing depression but no suicidal ideation or behavior in at least 6 months (n = 51), were examined in a case-control study for sleep quantity and quality, physical and psychological pain, pressure pain threshold, suicidal ideation, and recent suicidal behavior.

RESULTS

Sleep quality, physical and psychological pain were positively associated with suicidal ideation severity. In both cases in which sleep quality was added to a model with either physical or psychological pain, physical or psychological pain became more significantly associated with suicidal ideation severity. Pressure pain threshold was elevated in patients suffering from any type of insomnia. There was no significant association between pressure pain threshold and suicidal ideation severity.

CONCLUSIONS

The impact of these findings lies in the identification of both psychological and physical pain, and sleep quality as potential biological mechanisms underlying suicidal risk. HIGHLIGHTSWe assessed the association between pain and sleep quality in suicidal patients.Sleep quality, physical and psychological pain were associated with suicide risk.Pain perception may mediate the progression to suicidal behavior.

Hypertriton Production in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of _{Λ}^{3}H in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV is presented in this Letter. Its production yield measured in the rapidity interval -1<y<0 for the 40% highest-multiplicity p-Pb collisions is dN/dy=[6.3±1.8(stat)±1.2(syst)]×10^{-7}. The measurement is compared with the expectations of statistical hadronization and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in charged particle multiplicity environments relevant to small collision systems such as p-Pb, and therefore the measurement of dN/dy is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6.9σ of some configurations of the statistical hadronization model, thus constraining the theory behind the production of loosely bound states at hadron colliders.

Polarization of Λ and Λ[over ¯] Hyperons along the Beam Direction in Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV

The polarization of the Λ and Λ[over ¯] hyperons along the beam (z) direction, P_{z}, has been measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded with ALICE at the Large Hadron Collider (LHC). The main contribution to P_{z} comes from elliptic flow-induced vorticity and can be characterized by the second Fourier sine coefficient P_{z,s2}=⟨P_{z}sin(2φ-2Ψ_{2})⟩, where φ is the hyperon azimuthal emission angle and Ψ_{2} is the elliptic flow plane angle. We report the measurement of P_{z,s2} for different collision centralities and in the 30%-50% centrality interval as a function of the hyperon transverse momentum and rapidity. The P_{z,s2} is positive similarly as measured by the STAR Collaboration in Au-Au collisions at sqrt[s_{NN}]=200  GeV, with somewhat smaller amplitude in the semicentral collisions. This is the first experimental evidence of a nonzero hyperon P_{z} in Pb-Pb collisions at the LHC. The comparison of the measured P_{z,s2} with the hydrodynamic model calculations shows sensitivity to the competing contributions from thermal and the recently found shear-induced vorticity, as well as to whether the polarization is acquired at the quark-gluon plasma or the hadronic phase.

Synergistic effect of chronic pain and nonsuicidal self-harm on pain sensitivity

Abnormalities in pain processing have been observed in patients with chronic pain conditions and in individuals who engage in self-harm, specifically nonsuicidal self-injurious behaviors (NSSI). Both increased and decreased pain sensitivity have been described in chronic pain patients, while decreased pain sensitivity is consistently observed in individuals with NSSI. The objective of the study was to identify the differential effects of chronic pain and NSSI on experimental pain sensitivity, specifically pressure pain threshold, in depressed patients. Moreover, the role that hopelessness may play between depression severity and pain sensitivity was also examined. Depressed patients with and without chronic pain, and with and without lifetime self-harm behaviors were analyzed into four groups. Group 1 (N = 42) included depressed patients with both Chronic pain ( +) and Self-harm ( +), Group 2 (N = 53) included depressed patients with Chronic pain ( +) but no Self-harm (-), Group 3 (N = 64) included depressed patients without Chronic pain (-), but Self-harm ( +), and Group 4 (N = 81) included depressed patients with neither Chronic pain (-) nor Self-harm (-). Healthy controls (N = 45) were also recruited from the community. Depressed patients with both Chronic pain ( +) and Self-harm ( +) reported higher pressure pain threshold measures when compared with the other groups. Mediation analysis indicated that hopelessness mediates the relationship between depression severity and pressure pain threshold. Our findings suggest that a multiprong approach including adequate mental health services and pain control for depressed patients with comorbid chronic pain and nonsuicidal self-harm is needed to yield effective outcomes.

Measurement of the Groomed Jet Radius and Momentum Splitting Fraction in pp and Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

This article presents groomed jet substructure measurements in pp and Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector. The soft drop grooming algorithm provides access to the hard parton splittings inside a jet by removing soft wide-angle radiation. We report the groomed jet momentum splitting fraction, z_{g}, and the (scaled) groomed jet radius, θ_{g}. Charged-particle jets are reconstructed at midrapidity using the anti-k_{T} algorithm with resolution parameters R=0.2 and R=0.4. In heavy-ion collisions, the large underlying event poses a challenge for the reconstruction of groomed jet observables, since fluctuations in the background can cause groomed parton splittings to be misidentified. By using strong grooming conditions to reduce this background, we report these observables fully corrected for detector effects and background fluctuations for the first time. A narrowing of the θ_{g} distribution in Pb-Pb collisions compared to pp collisions is seen, which provides direct evidence of the modification of the angular structure of jets in the quark-gluon plasma. No significant modification of the z_{g} distribution in Pb-Pb collisions compared to pp collisions is observed. These results are compared with a variety of theoretical models of jet quenching, and provide constraints on jet energy-loss mechanisms and coherence effects in the quark-gluon plasma.

Measurement of Prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) Production in Proton-Proton Collisions at sqrt[s]=13 TeV

The p_{T}-differential production cross sections of prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) charmed hadrons are measured at midrapidity (|y|<0.5) in pp collisions at sqrt[s]=13  TeV. This is the first measurement of Σ_{c}^{0,++} production in hadronic collisions. Assuming the same production yield for the three Σ_{c}^{0,+,++} isospin states, the baryon-to-meson cross section ratios Σ_{c}^{0,+,++}/D^{0} and Λ_{c}^{+}/D^{0} are calculated in the transverse momentum (p_{T}) intervals 2<p_{T}<12 and 1<p_{T}<24  GeV/c. Values significantly larger than in e^{+}e^{-} collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the Σ_{c}. The feed-down contribution to Λ_{c}^{+} production from Σ_{c}^{0,+,++} is also reported and is found to be larger than in e^{+}e^{-} collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.

Measurement of the Cross Sections of Ξ_{c}^{0} and Ξ_{c}^{+} Baryons and of the Branching-Fraction Ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+}) in pp Collisions at sqrt[s]=13 TeV

The p_{T}-differential cross sections of prompt charm-strange baryons Ξ_{c}^{0} and Ξ_{c}^{+} were measured at midrapidity (|y|<0.5) in proton-proton (pp) collisions at a center-of-mass energy sqrt[s]=13  TeV with the ALICE detector at the LHC. The Ξ_{c}^{0} baryon was reconstructed via both the semileptonic decay (Ξ^{-}e^{+}ν_{e}) and the hadronic decay (Ξ^{-}π^{+}) channels. The Ξ_{c}^{+} baryon was reconstructed via the hadronic decay (Ξ^{-}π^{+}π^{+}) channel. The branching-fraction ratio BR(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/BR(Ξ_{c}^{0}→Ξ^{-}π^{+})=1.38±0.14(stat)±0.22(syst) was measured with a total uncertainty reduced by a factor of about 3 with respect to the current world average reported by the Particle Data Group. The transverse momentum (p_{T}) dependence of the Ξ_{c}^{0}- and Ξ_{c}^{+}-baryon production relative to the D^{0} meson and to the Σ_{c}^{0,+,++}- and Λ_{c}^{+}-baryon production are reported. The baryon-to-meson ratio increases toward low p_{T} up to a value of approximately 0.3. The measurements are compared with various models that take different hadronization mechanisms into consideration. The results provide stringent constraints to these theoretical calculations and additional evidence that different processes are involved in charm hadronization in electron-positron (e^{+}e^{-}) and hadronic collisions.

Altered physical pain processing in different psychiatric conditions

Several reports indicate either increased or decreased pain sensitivity associated with psychiatric disorders. Chronic pain is highly prevalent in many of these conditions. We reviewed the literature regarding experimental pain sensitivity in patients with major depression, bipolar disorder, posttraumatic stress disorder (PTSD), generalized anxiety disorder, panic disorder, obsessive-compulsive disorder and schizophrenia. Electronic searches were performed to identify studies comparing experimental pain in patients with these conditions and controls. Across 31 depression studies, reduced pain threshold was noted except for ischemic stimuli, where increased pain tolerance and elevated sensitivity to ischemic pain was observed. A more pervasive pattern of low pain sensitivity was found across 20 schizophrenia studies. The majority of PTSD studies (n = 20) showed no significant differences compared with controls. The limited number of bipolar disorder (n = 4) and anxiety (n = 9) studies precluded identification of clear trends. Wide data variability was observed. Awareness of psychiatric patients' pain perception abnormalities is needed for active screening and addressing physical comorbidities, in order to enhance quality of life, life expectancy and mental health.

Λ_{c}^{+} Production and Baryon-to-Meson Ratios in pp and p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV at the LHC

The prompt production of the charm baryon Λ_{c}^{+} and the Λ_{c}^{+}/D^{0} production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. These new measurements show a clear decrease of the Λ_{c}^{+}/D^{0} ratio with increasing transverse momentum (p_{T}) in both collision systems in the range 2<p_{T}<12  GeV/c, exhibiting similarities with the light-flavor baryon-to-meson ratios p/π and Λ/K_{S}^{0}. At low p_{T}, predictions that include additional color-reconnection mechanisms beyond the leading-color approximation, assume the existence of additional higher-mass charm-baryon states, or include hadronization via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in e^{+}e^{-} and e^{-}p collisions significantly underestimate the data. The results presented in this Letter provide significant evidence that the established assumption of universality (colliding-system independence) of parton-to-hadron fragmentation is not sufficient to describe charm-baryon production in hadronic collisions at LHC energies.

Experimental Evidence for an Attractive p-ϕ Interaction

This Letter presents the first experimental evidence of the attractive strong interaction between a proton and a ϕ meson. The result is obtained from two-particle correlations of combined p-ϕ⊕ p[over ¯]-ϕ pairs measured in high-multiplicity pp collisions at sqrt[s]=13  TeV by the ALICE Collaboration. The spin-averaged scattering length and effective range of the p-ϕ interaction are extracted from the fully corrected correlation function employing the Lednický-Lyuboshits approach. In particular, the imaginary part of the scattering length vanishes within uncertainties, indicating that inelastic processes do not play a prominent role for the p-ϕ interaction. These data demonstrate that the interaction is dominated by elastic p-ϕ scattering. Furthermore, an analysis employing phenomenological Gaussian- and Yukawa-type potentials is conducted. Under the assumption of the latter, the N-ϕ coupling constant is found to be g_{N-ϕ}=0.14±0.03(stat)±0.02(syst). This work provides valuable experimental input to accomplish a self-consistent description of the N-ϕ interaction, which is particularly relevant for the more fundamental studies on partial restoration of chiral symmetry in nuclear medium.

Temporal change in the diagnosis and treatment rates of osteoporosis: results from the Korea National Health and Nutrition Examination Survey

To compare the diagnosis andtreatment rates of osteoporosis and diabetes in Korea, a nationwide database was used. The results showed that although osteoporosis management is improving, it is still lower compared with that of diabetes; thus, further efforts are needed in this regard.

INTRODUCTION

This study aimed to re-evaluate the diagnosis and treatment of osteoporosis from the KNHANES 2016-2017 and compare the temporal change of the rate with those of diabetes as another prevalent chronic disease in South Korea.

METHODS

The prevalence of osteoporosis in 2016 was estimated using the previous data classified by age groups (50-59,60-69, and ≥70years) and the 2016 Korean census data. The physician diagnosis and treatment rates of osteoporosis in adults aged ≥50years were estimated using the 2016-2017 KNHANES data. The physician diagnosis and treatment rates of diabetes were evaluated using the KNHANES 2008-2009 and 2016-2017 data.

RESULTS

The estimated physician diagnosisrate of osteoporosis increased from 29.9% in females and 5.8% in males in 2008-2009 to 62.8% in females and 22.8% in males in 2016-2017. The treatment rate for the estimated total number of patients with osteoporosis increased from 14.4% in females and 3.8% in males in 2008-2009 to 32.2% in females and 9.0% in males in 2016-2017. An increasing trend in the estimated treatment rateof physician-diagnosed osteoporosis patients was not observed (48.3% [2008-2009] vs 51.5% [2016-2017] in females; 42.6% [2008-2009] vs 42.2% [2016-2017] in males). The physician diagnosis and treatment rates of diabetes were considerably better and more stable than those of osteoporosis.

CONCLUSION

Osteoporosis management in South Korea is improving but is insufficient compared with diabetes management. More extensive efforts are needed to improve the diagnosis and treatment rates of osteoporosis.

Multiharmonic Correlations of Different Flow Amplitudes in Pb-Pb Collisions at sqrt[s_{NN}]=2.76 TeV

The event-by-event correlations between three flow amplitudes are measured for the first time in Pb-Pb collisions, using higher-order symmetric cumulants. We find that different three-harmonic correlations develop during the collective evolution of the medium when compared to correlations that exist in the initial state. These new results cannot be interpreted in terms of previous lower-order flow measurements since contributions from two-harmonic correlations are explicitly removed in the new observables. A comparison to Monte Carlo simulations provides new and independent constraints for the initial conditions and system properties of nuclear matter created in heavy-ion collisions.

Soft-Dielectron Excess in Proton-Proton Collisions at sqrt[s]=13 TeV

A measurement of dielectron production in proton-proton (pp) collisions at sqrt[s]=13  TeV, recorded with the ALICE detector at the CERN LHC, is presented in this Letter. The data set was recorded with a reduced magnetic solenoid field. This enables the investigation of a kinematic domain at low dielectron (ee) invariant mass m_{ee} and pair transverse momentum p_{T,ee} that was previously inaccessible at the LHC. The cross section for dielectron production is studied as a function of m_{ee}, p_{T,ee}, and event multiplicity dN_{ch}/dη. The expected dielectron rate from hadron decays, called hadronic cocktail, utilizes a parametrization of the measured η/π^{0} ratio in pp and proton-nucleus collisions, assuming that this ratio shows no strong dependence on collision energy at low transverse momentum. Comparison of the measured dielectron yield to the hadronic cocktail at 0.15<m_{ee}<0.6  GeV/c^{2} and for p_{T,ee}<0.4  GeV/c indicates an enhancement of soft dielectrons, reminiscent of the "anomalous" soft-photon and soft-dilepton excess in hadron-hadron collisions reported by several experiments under different experimental conditions. The enhancement factor over the hadronic cocktail amounts to 1.61±0.13(stat)±0.17(syst,data)±0.34(syst,cocktail) in the ALICE acceptance. Acceptance-corrected excess spectra in m_{ee} and p_{T,ee} are extracted and compared with calculations of dielectron production from hadronic bremsstrahlung and thermal radiation within a hadronic many-body approach.

Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The elliptic flow of electrons from beauty hadron decays at midrapidity (|y|<0.8) is measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The azimuthal distribution of the particles produced in the collisions can be parametrized with a Fourier expansion, in which the second harmonic coefficient represents the elliptic flow, v_{2}. The v_{2} coefficient of electrons from beauty hadron decays is measured for the first time in the transverse momentum (p_{T}) range 1.3-6  GeV/c in the centrality class 30%-50%. The measurement of electrons from beauty-hadron decays exploits their larger mean proper decay length cτ≈500  μm compared to that of charm hadrons and most of the other background sources. The v_{2} of electrons from beauty hadron decays at midrapidity is found to be positive with a significance of 3.75  σ. The results provide insights into the degree of thermalization of beauty quarks in the medium. A model assuming full thermalization of beauty quarks is strongly disfavored by the measurement at high p_{T}, but is in agreement with the results at low p_{T}. Transport models including substantial interactions of beauty quarks with an expanding strongly interacting medium describe the measurement within uncertainties.

Examination of physician factors influencing psychiatric assessment of acutely suicidal patients

Suicide risk assessment is a subjective process and remains a clinical challenge in psychiatry. We aimed to examine physicians' characteristics that influence management of acutely suicidal patients. In a cross-sectional design, we performed an anonymous internet survey of psychiatry residents and attendings from four academic centers. Gender, years of experience, practice setting, prior patient suicide, and personal exposure to suicide were characterized. Participants were presented with three clinical vignettes and asked to rate suicide risk and clinical disposition. The relationship between responses to the vignettes and physician characteristics were examined with generalized linear models. Fifty-four residents and 49 attendings completed the survey. Four (7%) residents and 24 (49%) attendings had patients die by suicide, whereas 32 (59%) and 36 (74%), respectively, knew somebody outside their practice who died by suicide. Among residents, lower rating of acute suicide risk was associated with prior exposure to non-patient suicide. Less hospitalization chosen by attendings was associated with greater perceived difficulty of suicide risk assessment. In the combined resident and attending sample, less proneness to hospitalize was associated with number of previous patients die by suicide and with outpatient practice. Our results suggest that previous exposure to suicide is associated with more risk-averse management.

Aberrant Brain Signal Variability and COMT Genotype in Chronic TMD Patients

The analysis of brain signal variability is a promising approach to understand pathological brain function related to chronic pain. This study investigates whether blood-oxygen-level-dependent signal variability (BOLD_SV) in specific frequency bands is altered in temporomandibular disorder (TMD) and correlated to its clinical features. Twelve patients with chronic myofascial TMD and 24 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging. The BOLD_SV was measured as the standard deviation of the BOLD time series at each voxel and compared between groups. We also examined the potential relationship between the BOLD_SV and the catechol-O-methyltransferase (COMT) Val¹⁵⁸Met polymorphism. We assessed sensory-discriminative pain in the craniofacial region, pain sensitivity to sustained masseteric pain challenge, and TMD pain frequency for clinical correlation. Patients displayed reduced BOLD_SV in the dorsolateral prefrontal cortex (dlPFC) as compared with HC in all frequency bands. In the slow-3 band, patients also showed reduced BOLD_SV in the medial dorsal thalamus, primary motor cortex (M1), and primary somatosensory cortex (S1) and heightened BOLD_SV in the temporal pole. Notably, we found a significant correlation between lower BOLD_SV (slow-3) in the orofacial M1/S1 regions and higher clinical pain (intensity/area) and higher sensitivity of the masseter muscle pain. Moreover, lower BOLD_SV (slow-3) in the dlPFC and ventrolateral PFC was associated with a higher TMD pain frequency. Participants who had the COMT ¹⁵⁸Met substitution exhibited lower BOLD_SV in the dlPFC and higher BOLD_SV in the temporal pole as compared with participants without the COMT ¹⁵⁸Met substitution. An increasing number of Met alleles was associated with lower dlPFC and greater temporal pole BOLD_SV in both HC and TMD groups. Together, we demonstrated that chronic TMD patients exhibit aberrant BOLD_SV in the top-down pain modulatory and sensorimotor circuits associated with their pain frequency and severity. COMT Val¹⁵⁸Met polymorphism might affect clinical symptoms in association with regional brain signal variability, specifically involved in cognitive and emotional regulation of pain.

Clot Meniscus Sign: An Angiographic Clue for Choosing between Stent Retriever and Contact Aspiration in Acute Basilar Artery Occlusion

BACKGROUND AND PURPOSE

The efficacy of mechanical thrombectomy methods may differ depending on the characteristics of the occlusion. The purpose of this study was to compare the recanalization efficacy and treatment outcome of a stent retriever versus contact aspiration in patients with acute basilar artery occlusion according to the angiographic characteristics of the occlusion.

MATERIALS AND METHODS

One hundred sixty-one patients with acute basilar artery occlusion who underwent mechanical thrombectomy were retrospectively analyzed. A stent retriever was compared with contact aspiration thrombectomy according to the clot meniscus sign, defined as a meniscoid/tram-track-like sidewall contrast opacification of the thrombus. A propensity score matching analysis was performed. Clinical/angiographic characteristics and treatment and clinical outcomes were compared.

RESULTS

Overall, a stent retriever (n = 118) and contact aspiration (n = 43) did not show significant differences in the successful recanalization (82.2% versus 86.0%) and good clinical outcome rates (32.2% versus 39.5%). In patients with the positive meniscus sign, contact aspiration was associated with shorter procedural time (44 versus 26 minutes, P = .018), a lower number of passes (2 versus 1, P = .041), a higher complete recanalization rate (58.8% versus 85.7%, P = .021), and a higher rate of first-pass effect (27.9% versus 53.6%, P = .031) compared with a stent retriever. After propensity score matching, contact aspiration was associated with higher complete recanalization rates (59.3% versus 85.7%, P = .033). No significant differences in the outcomes were noted between a stent retriever and contact aspiration in patients negative for the meniscus sign.

CONCLUSIONS

The efficacy of the mechanical thrombectomy techniques may differ according to the angiographic characteristics of occlusion in patients with basilar artery occlusion. Contact aspiration may be more effective in terms of recanalization compared with a stent retriever in patients with the clot meniscus sign.

Examination of structural brain changes in recent suicidal behavior

We aimed to identify brain structural changes in cortical and subcortical regions linked to recent suicidal behavior. We performed secondary analyses of structural MRI data of two independent studies, namely the Establishing Moderators/Biosignatures of Antidepressant Response - Clinical Care (EMBARC) study and a Little Rock study on acute suicidal behavior. Study 1 (EMBARC, N = 187), compared individuals with remote suicide attempts (Remote-SA), individuals with lifetime suicide ideation but no attempts (Lifetime-SI only), and depressed individuals without lifetime suicide ideation or attempts (non-suicidal depressed). Study 2 (Little Rock data, N = 34) included patients recently hospitalized for suicide ideation or attempt constituted by: patients who recently attempted suicide (Recent-SA), individuals with remote suicide attempts (Remote-SA), and Lifetime-SI only. Study 3 combined the EMBARC and Little Rock datasets including Recent-SA, Remote-SA, Lifetime-SI only and non-suicidal depressed individuals. In Study 1 and Study 2, no significant differences were observed between groups. In Study 3, significantly lower middle temporal gyrus thickness, insular surface area, and thalamic volume and higher volume in the nucleus accumbens were observed in Recent-SA. This pattern of structural abnormalities may underlie pain and emotion dysregulation, which have been linked to the transition from suicidal thoughts to action.

Measurement of the Low-Energy Antideuteron Inelastic Cross Section

In this Letter, we report the first measurement of the inelastic cross section for antideuteron-nucleus interactions at low particle momenta, covering a range of 0.3≤p<4  GeV/c. The measurement is carried out using p-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of sqrt[s_{NN}]=5.02  TeV, recorded with the ALICE detector at the CERN LHC and utilizing the detector material as an absorber for antideuterons and antiprotons. The extracted raw primary antiparticle-to-particle ratios are compared to the results from detailed ALICE simulations based on the geant4 toolkit for the propagation of (anti)particles through the detector material. The analysis of the raw primary (anti)proton spectra serves as a benchmark for this study, since their hadronic interaction cross sections are well constrained experimentally. The first measurement of the inelastic cross section for antideuteron-nucleus interactions averaged over the ALICE detector material with atomic mass numbers ⟨A⟩=17.4 and 31.8 is obtained. The measured inelastic cross section points to a possible excess with respect to the Glauber model parametrization used in geant4 in the lowest momentum interval of 0.3≤p<0.47  GeV/c up to a factor 2.1. This result is relevant for the understanding of antimatter propagation and the contributions to antinuclei production from cosmic ray interactions within the interstellar medium. In addition, the momentum range covered by this measurement is of particular importance to evaluate signal predictions for indirect dark-matter searches.

Hyperattenuating lesions after mechanical thrombectomy in acute ischaemic stroke: factors predicting symptomatic haemorrhage and clinical outcomes

AIM

To evaluate the clinical significance of hyperattenuating lesions on CT after mechanical thrombectomy for acute ischaemic stroke, and to identify imaging factors that predict symptomatic haemorrhage and unfavourable outcomes.

MATERIALS AND METHODS

Seventy-eight patients with acute ischaemic stroke in the anterior circulation who underwent mechanical thrombectomy were evaluated. All patients underwent post-interventional unenhanced computed tomography (CT) within 24 h and follow-up CT or magnetic resonance imaging (MRI) within 7 days. Baseline characteristics and clinical outcomes were compared between patients with and without hyperattenuating lesions. In patients with hyperattenuating lesions, clinical and imaging factors that predict symptomatic haemorrhage and unfavourable outcomes were determined.

RESULTS

Fifty-six of 78 patients (71.8%) demonstrated hyperattenuating lesions on post-interventional CT. Patients with hyperattenuating lesions showed lower Alberta Stroke Program Early CT score (ASPECTS), persistent/symptomatic haemorrhage, and unfavourable outcomes than those without. In patients with hyperattenuating lesions, larger hyperattenuating lesion volume (>21.3 ml; OR, 55.60, p<0.001) and perilesional oedema (OR, 46.04, p=0.015) were independent factors predicting symptomatic haemorrhage. Older age (OR, 1.2, p=0.006) and lower ASPECTS (OR, 0.45, p=0.046) were independent factors predicting unfavourable outcomes in patients with hyperattenuating lesions. Adding the volume of the hyperattenuating lesion to age and ASPECTS increased the predictive performance of unfavourable outcomes (area under the curve 0.874 versus 0.934, p=0.043).

CONCLUSIONS

Hyperattenuating lesions on post-interventional CT are associated with increased risk of symptomatic haemorrhage and unfavourable outcomes. Larger hyperattenuating lesion volume is an independent factor of symptomatic haemorrhage and it has added predictive value for unfavourable outcomes.

Erratum: Evolution of π^{0} Suppression in Au+Au Collisions from sqrt[s_{NN}]=39 to 200 GeV [Phys. Rev. Lett. 109, 152301 (2012)]

This corrects the article DOI: 10.1103/PhysRevLett.109.152301.

Probing the Effects of Strong Electromagnetic Fields with Charge-Dependent Directed Flow in Pb-Pb Collisions at the LHC

The first measurement at the LHC of charge-dependent directed flow (v_{1}) relative to the spectator plane is presented for Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. Results are reported for charged hadrons and D^{0} mesons for the transverse momentum intervals p_{T}>0.2  GeV/c and 3<p_{T}<6  GeV/c in the 5%-40% and 10%-40% centrality classes, respectively. The difference between the positively and negatively charged hadron v_{1} has a positive slope as a function of pseudorapidity η, dΔv_{1}/dη=[1.68±0.49(stat)±0.41(syst)]×10^{-4}. The same measurement for D^{0} and D[over ¯]^{0} mesons yields a positive value dΔv_{1}/dη=[4.9±1.7(stat)±0.6(syst)]×10^{-1}, which is about 3 orders of magnitude larger than the one of the charged hadrons. These measurements can provide new insights into the effects of the strong electromagnetic field and the initial tilt of matter created in noncentral heavy ion collisions on the dynamics of light (u, d, and s) and heavy (c) quarks. The large difference between the observed Δv_{1} of charged hadrons and D^{0} mesons may reflect different sensitivity of the charm and light quarks to the early time dynamics of a heavy ion collision. These observations challenge some recent theoretical calculations, which predicted a negative and an order of magnitude smaller value of dΔv_{1}/dη for both light flavor and charmed hadrons.

Evidence of Spin-Orbital Angular Momentum Interactions in Relativistic Heavy-Ion Collisions

The first evidence of spin alignment of vector mesons (K^{*0} and ϕ) in heavy-ion collisions at the Large Hadron Collider (LHC) is reported. The spin density matrix element ρ_{00} is measured at midrapidity (|y|<0.5) in Pb-Pb collisions at a center-of-mass energy (sqrt[s_{NN}]) of 2.76 TeV with the ALICE detector. ρ_{00} values are found to be less than 1/3 (1/3 implies no spin alignment) at low transverse momentum (p_{T}<2  GeV/c) for K^{*0} and ϕ at a level of 3σ and 2σ, respectively. No significant spin alignment is observed for the K_{S}^{0} meson (spin=0) in Pb-Pb collisions and for the vector mesons in pp collisions. The measured spin alignment is unexpectedly large but qualitatively consistent with the expectation from models which attribute it to a polarization of quarks in the presence of angular momentum in heavy-ion collisions and a subsequent hadronization by the process of recombination.

Efficacy and Safety of Flow-Diverter Therapy for Recurrent Aneurysms after Stent-Assisted Coiling

BACKGROUND AND PURPOSE

Flow-diverter treatment for previously stented aneurysms has been reported to be less effective and prone to complications. In this study, we evaluated the effectiveness and safety of flow diverters for recurrent aneurysms after stent-assisted coiling.

MATERIALS AND METHODS

Patients who underwent flow-diverter placement for recurrent aneurysms after stent-assisted coiling between March 2015 and March 2019 were recruited. Clinical and radiographic characteristics and clinical and angiographic outcomes were retrospectively evaluated.

RESULTS

Among 133 patients who underwent flow-diverter insertion, 17 (male/female ratio = 5:12; mean age, 53.8 years) were treated for recurrent aneurysms after stent placement with (n = 16) or without (n = 1) coiling. Eight patients initially presented with subarachnoid hemorrhage; 7, with headache; and 2, with visual field defects. Angiographic morphology included large/giant saccular in 12 patients, dissecting in 2, fusiform in 1, traumatic pseudoaneurysm in 1, and ruptured blood blister-like aneurysm in 1. The duration between the first treatment and flow-diverter placement ranged from 2 weeks to 15 months (median, 6 months). Flow-diverter placement was successful in all cases without any complications. All patients had favorable outcomes (mRS, 0-2), without any newly appearing symptoms. Aneurysms were followed up with conventional angiography at least once in 6-18 months. Sixteen aneurysms showed complete occlusion, and 1 aneurysm was enlarged.

CONCLUSIONS

Results from this case series investigating flow-diverter placement for recurrent aneurysms after stent-assisted coiling suggested that the procedure is safe and effective. Further study in a larger population may be warranted.

Scattering Studies with Low-Energy Kaon-Proton Femtoscopy in Proton-Proton Collisions at the LHC

The study of the strength and behavior of the antikaon-nucleon (K[over ¯]N) interaction constitutes one of the key focuses of the strangeness sector in low-energy quantum chromodynamics (QCD). In this Letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K^{+}p⊕K^{-}p[over ¯]) and (K^{-}p⊕K^{+}p[over ¯]) pairs measured in pp collisions at sqrt[s]=5, 7, and 13 TeV are reported. A structure observed around a relative momentum of 58  MeV/c in the measured correlation function of (K^{-}p⊕K^{+}p[over ¯]) with a significance of 4.4σ constitutes the first experimental evidence for the opening of the (K[over ¯]^{0}n⊕K^{0}n[over ¯]) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to Jülich and Kyoto models in addition to the Coulomb potential. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K[over ¯]N threshold for low-energy QCD chiral models.

Migrant status and identification as ultra-high risk for psychosis and transitioning to a psychotic disorder

BACKGROUND

Certain migrant groups are more likely to develop a psychotic disorder compared to the native-born populations, and a younger age at migration is associated with greater risk. However, it is not known at which stage migration has an effect on the development of psychotic disorders. We examined whether migrants were more likely to be identified as ultra-high risk for psychosis (UHR) compared to native-born young people and whether migrant status was associated with the risk of transition to a full-threshold psychotic disorder.

METHODS

The cohort included all young people aged 15-24 who were identified as UHR at a specialist clinic over a five-year period (2012-16). Australian census data were used to obtain the at-risk population. Poisson regression was used to calculate rate ratios and Cox regression analysis determined hazard ratios.

RESULTS

467 young people were identified as UHR, of which 13.5% (n = 63) were born overseas. First-generation migrants were 2.6-fold less likely to be identified as UHR compared to Australian-born young people (IRR = 0.39, 95% CI [0.30, 0.51], P < 0.001). There was no difference between migrant and native-born young people in their risk of transitioning to a psychotic disorder (HR = 0.90, 95% CI [0.39, 2.08], P = 0.81).

CONCLUSIONS

UHR first-generation migrants may be under-accessing mental health services.

Examination of pain threshold and neuropeptides in patients with acute suicide risk

INTRODUCTION

One of the main challenges in suicide prevention is the limited understanding of the biological mechanisms underlying suicide. Recent findings suggest impairments in pain processing in acutely suicidal patients. However, little is known about the biological factors that may drive these discrete physiological abnormalities. In this study, we examined plasma peptides involved in analgesic and inflammatory responses and physical pain threshold in acutely suicidal patients.

METHODS

Thirty-seven depressed patients of both sexes hospitalized for severe suicidal ideation or a recent suicide attempt were characterized clinically including history of suicidal ideation and behavior. Psychological and physical pain, and pressure pain threshold was also measured. Plasma levels of β-endorphin, neurotensin, agouti-related protein (AgRP), C-reactive protein (CRP), adrenocorticotropic hormone (ACTH), and brain-derived neurotrophic factor (BDNF) were run in Milliplex multiplex assays.

RESULTS

The number of lifetime suicide attempts was positively correlated with β-endorphin (r = 0.702; p = 0.007), and neurotensin (r = 0.728, p = 0.007) plasma levels. Higher pain threshold was measured in the suicide attempt group as compared to the suicidal ideation group. Pain threshold was strongly and negatively associated with CRP plasma levels (r = -0.548; p < 0.001). In patients reporting chronic pain, lower AgRP levels and lower pain threshold were observed (t = 4.472; p = 0.001).

CONCLUSION

Our results suggest that abnormalities in the opioid and neurotensin systems may underlie the increase in pain threshold found in suicide attempters, and possibly risk for suicidal behavior. Targeting pain circuits and systems may provide therapeutic mechanisms for suicide prevention.

Measurement of ϒ(1S) Elliptic Flow at Forward Rapidity in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The first measurement of the ϒ(1S) elliptic flow coefficient (v_{2}) is performed at forward rapidity (2.5<y<4) in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The results are obtained with the scalar product method and are reported as a function of transverse momentum (p_{T}) up to 15  GeV/c in the 5%-60% centrality interval. The measured ϒ(1S)v_{2} is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v_{2} coefficient in 2<p_{T}<15  GeV/c is lower than that of inclusive J/ψ mesons in the same p_{T} interval by 2.6 standard deviations. These results, combined with earlier suppression measurements, are in agreement with a scenario in which the ϒ(1S) production in Pb-Pb collisions at LHC energies is dominated by dissociation limited to the early stage of the collision, whereas in the J/ψ case there is substantial experimental evidence of an additional regeneration component.

Investigations of Anisotropic Flow Using Multiparticle Azimuthal Correlations in pp, p-Pb, Xe-Xe, and Pb-Pb Collisions at the LHC

Measurements of anisotropic flow coefficients (v_{n}) and their cross-correlations using two- and multiparticle cumulant methods are reported in collisions of pp at sqrt[s]=13  TeV, p-Pb at a center-of-mass energy per nucleon pair sqrt[s_{NN}]=5.02  TeV, Xe-Xe at sqrt[s_{NN}]=5.44  TeV, and Pb-Pb at sqrt[s_{NN}]=5.02  TeV recorded with the ALICE detector. The multiplicity dependence of v_{n} is studied in a very wide range from 20 to 3000 particles produced in the midrapidity region |η|<0.8 for the transverse momentum range 0.2<p_{T}<3.0  GeV/c. An ordering of the coefficients v_{2}>v_{3}>v_{4} is found in pp and p-Pb collisions, similar to that seen in large collision systems, while a weak v_{2} multiplicity dependence is observed relative to nucleus-nucleus collisions in the same multiplicity range. Using a novel subevent method, v_{2} measured with four-particle cumulants is found to be compatible with that from six-particle cumulants in pp and p-Pb collisions. The magnitude of the correlation between v_{n}^{2} and v_{m}^{2}, evaluated with the symmetric cumulants SC(m,n) is observed to be positive at all multiplicities for v_{2} and v_{4}, while for v_{2} and v_{3} it is negative and changes sign for multiplicities below 100, which may indicate a different v_{n} fluctuation pattern in this multiplicity range. The observed long-range multiparticle azimuthal correlations in high multiplicity pp and p-Pb collisions can neither be described by pythia 8 nor by impact-parameter-Glasma, music, and ultrarelativistic quantum molecular dynamics model calculations, and hence, provide new insights into the understanding of collective effects in small collision systems.

First Observation of an Attractive Interaction between a Proton and a Cascade Baryon

This Letter presents the first experimental observation of the attractive strong interaction between a proton and a multistrange baryon (hyperon) Ξ^{-}. The result is extracted from two-particle correlations of combined p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} pairs measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC with ALICE. The measured correlation function is compared with the prediction obtained assuming only an attractive Coulomb interaction and a standard deviation in the range [3.6, 5.3] is found. Since the measured p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} correlation is significantly enhanced with respect to the Coulomb prediction, the presence of an additional, strong, attractive interaction is evident. The data are compatible with recent lattice calculations by the HAL-QCD Collaboration, with a standard deviation in the range [1.8, 3.7]. The lattice potential predicts a shallow repulsive Ξ^{-} interaction within pure neutron matter and this implies stiffer equations of state for neutron-rich matter including hyperons. Implications of the strong interaction for the modeling of neutron stars are discussed.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

Abstract 428: Phenotyping pancreatic cancer CTCs as biomarkers for RX-3117 clinical trials

Background:

RX-3117 is an oral, small molecule nucleoside analogue pro-drug being used in combination with nab-paclitaxel in a Ph2 clinical trial for pancreatic cancer. RX-3117 can be transported intracellularly by SLC29A1 (hENT1) and is converted to an active agent by the cancer-enriched enzyme, uridine-cytidine kinase 2 (UCK2) for incorporation into RNA and DNA. This leads to cancer cell apoptosis. We developed an approach to enumerate and phenotype CTCs from pancreatic cancer subjects by quantitative immunofluorescence (QIF) to assess whether CTC numbers, phenotypic features and/or early apoptotic responses to therapy predict or presage clinical response.

Methods:

QIF staining parameters were developed with cancer cell lines sensitive and resistant to RX-3117 utilizing monoclonal antibodies to hENT1 and UCK2. The staining methods were then applied to CTCs isolated from 10 ml anticoagulated blood by dielectrophoretic (DEP) properties that differentiate cancer cells and normal PBMCs using the ApoStream device (ApoCell, TX). In addition to the drug-related markers, CTCs were stained for a panel of either Epithelial or Mesenchymal markers, CD45 and nuclei (DAPI). Phenotyped CTCs were binned into 6 categories defined by whether they were EPI+/-, EMT+/- or CD45+/-. The percentage of cells in each category also positive for hENT1 or UCK2 was determined as was the mean fluorescence intensity of the marker+ sub-population. In addition, assessment of hENT1 and UCK2 expression was performed by qRT-PCR utilizing mRNA isolated from isolated CTCs, the buffy coat from spun blood and in plasma.

Results:

In a pilot study, blood was obtained from five subjects with Stage IV pancreatic cancer on various regimens. CTCs were isolated, enumerated and phenotyped. CTC numbers ranged from 100 – 20,000 per ml. The percentages of UCK2+ cells were higher in EPI+/EMT+ subsets than EPI-/EMT- subsets. The percentages of hENT1+ cells were generally low in all the subsets. hENT1 and UCK2 transcripts were observed at acceptable levels in the cell populations, and borderline, but consistent levels in plasma samples. CEACAM5 transcripts were observed only in one CTC and PBMC fraction from one subject. After normalization vs. housekeeping transcripts, a greater than 2-fold increase of UCK2 was observed in three CTC samples compared to PBMC samples. A greater than 2-fold increase of hENT1 was observed in two CTC samples.

Conclusion:

CTCs from patients with pancreatic cancer can be obtained in numbers suitable for multiparameter phenotyping to identify features that might serve as selective, predictive or prognostic biomarkers in clinical trials. Multiparameter phenotyping of several relevant markers is being performed by quantitative immunofluorescence on CTCs isolated from pancreatic cancer patients in an on-going Ph2 clinical trial of RX-3117 in combination with nab-paclitaxel.

Citation Format: Andrew Eisen, DJ Kim, Jie Yang, Weiguo Wu, Darren W. Davis. Phenotyping pancreatic cancer CTCs as biomarkers for RX-3117 clinical trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 428.

Impact of Balloon-Guiding Catheter Location on Recanalization in Patients with Acute Stroke Treated by Mechanical Thrombectomy

BACKGROUND AND PURPOSE

Mechanical thrombectomy with proximal flow control and forced aspiration may improve the outcome of endovascular revascularization therapy for patients with acute stroke. The purpose of this study was to compare the impact of balloon-guiding catheter locations in patients treated for anterior circulation acute ischemic stroke using mechanical thrombectomy.

MATERIALS AND METHODS

The influence of the balloon-guiding catheter location (proximal, balloon-guiding catheter tip proximal to C1 vertebral body; distal, between the skull base and the C1 vertebral body) was analyzed in patients with acute anterior circulation stroke treated with stent-retriever thrombectomy. The baseline angiographic/clinical characteristics, time intervals, recanalization rates, and clinical outcomes were compared.

RESULTS

The clinical analysis included 102 patients (mean age, 69.5 ± 12.8 years; male/female ratio = 52:50). The balloon-guiding catheter was located distally in 49 patients and proximally in 53 patients for flow control and forced aspiration during stent retrieval. The puncture-to-recanalization time was shorter in the distal group than in the proximal group (40 versus 56 minutes, P = .02). Successful and complete recanalizations were more frequently achieved in the distal group compared with the proximal group (98.0% versus 75.5%. P = .003; 67.3% versus 45.3%, P = .04, respectively). Multivariate analysis showed that the distal catheterization location was independently associated with successful recanalization (adjusted OR, 13.4; 95% CI, 2.4-254.8; P = .02).

CONCLUSIONS

Location of the balloon-guiding catheter has a significant impact on recanalization in patients with acute stroke. The balloon-guiding catheter should be positioned as distally as safely possible in the cervical ICA for maximally effective thrombectomy.

Clinical Impact of a Protocolized Kidney Donor Follow-up System

BACKGROUND

Adequate kidney donor management after donation is increasingly emphasized due to concerns of renal function impairment after nephrectomy with increasing life expectancy. In this study, the clinical impact of a protocolized kidney donor follow-up system by nephrologists was evaluated.

METHODS

A total of 427 living kidney donors underwent nephrectomy from January 2010 to December 2014 and were followed for at least 2 years at the Samsung Medical Center. Donors were followed-up by nephrologists after the establishment of a donor clinic with systemized protocols in January 2013. The primary outcomes were incidence of post-donation low estimated glomerular filtration rate (eGFR) and renal function adaptability. Secondary outcomes were changes in compliance and incidence of hyperuricemia and microalbuminuria.

RESULTS

The patients were divided into 2 groups according to the time of nephrectomy: the pre-donor clinic period (n = 182) and the donor clinic period (n = 172). Preoperative eGFR in patients in the pre-donor clinic period was higher than that in patients in the donor clinic period. After donation, poor renal adaptation was less frequent in the donor clinic period compared to the pre-donor clinic period. Low eGFR tended to be less common during the donor clinic period. Shorter mean outpatient clinic visit intervals with more visits within 6 months after donation and earlier detection of de novo hyperuricemia were found during the donor clinic period.

CONCLUSION

A protocolized donor clinic run by nephrologists may improve post-nephrectomy renal outcomes and compliance and facilitate better management of potential risk factors of chronic kidney disease in donors.

Azimuthal Anisotropy of Heavy-Flavor Decay Electrons in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Angular correlations between heavy-flavor decay electrons and charged particles at midrapidity (|η|<0.8) are measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. The analysis is carried out for the 0%-20% (high) and 60%-100% (low) multiplicity ranges. The jet contribution in the correlation distribution from high-multiplicity events is removed by subtracting the distribution from low-multiplicity events. An azimuthal modulation remains after removing the jet contribution, similar to previous observations in two-particle angular correlation measurements for light-flavor hadrons. A Fourier decomposition of the modulation results in a positive second-order coefficient (v_{2}) for heavy-flavor decay electrons in the transverse momentum interval 1.5<p_{T}<4  GeV/c in high-multiplicity events, with a significance larger than 5σ. The results are compared with those of charged particles at midrapidity and those of inclusive muons at forward rapidity. The v_{2} measurement of open heavy-flavor particles at midrapidity in small collision systems could provide crucial information to help interpret the anisotropies observed in such systems.

Clinical characteristics of diabetic ketoacidosis in users and non-users of SGLT2 inhibitors

AIM

This study investigated the clinical characteristics of diabetic ketoacidosis (DKA) and compared the DKA characteristics between patients treated with and without SGLT2 inhibitors.

METHODS

Data were collected from patients aged ≥ 18 years admitted for DKA at nine centres in Korea between September 2014 and April 2017. The electronic medical records of these subjects were retrospectively reviewed. Based on their history of medications taken before admission, subjects were classified as either users or non-users of SGLT2 inhibitors and their clinical characteristics of DKA were compared.

RESULTS

During the study, the main subtype of DKA episodes (n = 523) was identified as type 2 diabetes (51%). Average hospitalization duration was 11 days, and average intensive care unit (ICU) time was 2.5 days. The in-hospital mortality rate was 3%, but no users of SGLT2 inhibitors died during DKA treatment. In patients taking SGLT2 inhibitors (n = 15), DKA manifested at 124 days, on average, after starting the inhibitors (range: 7-380 days). Also, SGLT2 inhibitors users had significantly lower plasma glucose levels (413 mg/dL) compared with non-users (554 mg/dL), and longer ICU stays (4 vs. 2 days; P = 0.019).

CONCLUSION

In this report of recent data on the clinical features of DKA in Korea, patients using SGLT2 inhibitors needed longer treatment in ICUs compared with non-users and had lower levels of blood glucose, whereas DKA associated with SGLT2 inhibitors was rare.