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During the solar minimum, when the Sun is at its least active, the solar wind1,2 is observed at high latitudes as a predominantly fast (more than 500 kilometres per second), highly Alfvénic rarefied stream of plasma originating from deep within coronal holes. Closer to the ecliptic plane, the solar wind is interspersed with a more variable slow wind3 of less than 500 kilometres per second. The precise origins of the slow wind streams are less certain4; theories and observations suggest that they may originate at the tips of helmet streamers5,6, from interchange reconnection near coronal hole boundaries7,8, or within coronal holes with highly diverging magnetic fields9,10. The heating mechanism required to drive the solar wind is also unresolved, although candidate mechanisms include Alfvén-wave turbulence11,12, heating by reconnection in nanoflares13, ion cyclotron wave heating14 and acceleration by thermal gradients1. At a distance of one astronomical unit, the wind is mixed and evolved, and therefore much of the diagnostic structure of these sources and processes has been lost. Here we present observations from the Parker Solar Probe15 at 36 to 54 solar radii that show evidence of slow Alfvénic solar wind emerging from a small equatorial coronal hole. The measured magnetic field exhibits patches of large, intermittent reversals that are associated with jets of plasma and enhanced Poynting flux and that are interspersed in a smoother and less turbulent flow with a near-radial magnetic field. Furthermore, plasma-wave measurements suggest the existence of electron and ion velocity-space micro-instabilities10,16 that are associated with plasma heating and thermalization processes. Our measurements suggest that there is an impulsive mechanism associated with solar-wind energization and that micro-instabilities play a part in heating, and we provide evidence that low-latitude coronal holes are a key source of the slow solar wind.
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The J/ψ, ψ(3686)âΣ^{0}Σ[over ¯]^{0} processes and subsequent decays are studied using the world's largest J/ψ and ψ(3686) data samples collected with the BESIII detector. The parity-violating decay parameters of the decays Σ^{0}âΛγ and Σ[over ¯]^{0}âΛ[over ¯]γ, α_{Σ^{0}}=-0.0017±0.0021±0.0018 and α[over ¯]_{Σ^{0}}=0.0021±0.0020±0.0022, are measured for the first time. The strong CP symmetry is tested in the decays of the Σ^{0} hyperons for the first time by measuring the asymmetry A_{CP}^{Σ}=α_{Σ^{0}}+α[over ¯]_{Σ^{0}}=(0.4±2.9±1.3)×10^{-3}. The weak CP test is performed in the subsequent decays of their daughter particles Λ and Λ[over ¯]. Also for the first time, the transverse polarizations of the Σ^{0} hyperons in J/ψ and ψ(3686) decays are observed with opposite directions, and the ratios between the S-wave and D-wave contributions of the J/ψ, ψ(3686)âΣ^{0}Σ[over ¯]^{0} decays are obtained. These results are crucial to understand the decay dynamics of the charmonium states and the production mechanism of the Σ^{0}-Σ[over ¯]^{0} pairs.
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Using 7.33 fb^{-1} of e^{+}e^{-} collision data collected by the BESIII detector at center-of-mass energies in the range of sqrt[s]=4.128-4.226 GeV, we search for the rare decays D_{s}^{+}âh^{+}(h^{0})e^{+}e^{-}, where h represents a kaon or pion. By requiring the e^{+}e^{-} invariant mass to be consistent with a Ï(1020), 0.98
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Using (10.087±0.044)×10^{9} J/ψ events collected with the BESIII detector at the BEPCII storage ring, the processes ΛpâΛp and Λ[over ¯]pâΛ[over ¯]p are studied, where the Λ/Λ[over ¯] baryons are produced in the process J/ψâΛΛ[over ¯] and the protons are the hydrogen nuclei in the cooling oil of the beam pipe. Clear signals are observed for the two reactions. The cross sections in -0.9≤cosθ_{Λ/Λ[over ¯]}≤0.9 are measured to be σ(ΛpâΛp)=(12.2±1.6_{stat}±1.1_{syst}) and σ(Λ[over ¯]pâΛ[over ¯]p)=(17.5±2.1_{stat}±1.6_{syst}) mb at the Λ/Λ[over ¯] momentum of 1.074 GeV/c within a range of ±0.017 GeV/c, where the θ_{Λ/Λ[over ¯]} are the scattering angles of the Λ/Λ[over ¯] in the Λp/Λ[over ¯]p rest frames. Furthermore, the differential cross sections of the two reactions are also measured, where there is a slight tendency of forward scattering for ΛpâΛp, and a strong forward peak for Λ[over ¯]pâΛ[over ¯]p. We present an approach to extract the total elastic cross sections by extrapolation. The study of Λ[over ¯]pâΛ[over ¯]p represents the first study of antihyperon-nucleon scattering, and these new measurements will serve as important inputs for the theoretical understanding of the (anti)hyperon-nucleon interaction.
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Using data samples collected with the BESIII detector operating at the BEPCII storage ring, the cross section of the inclusive process e^{+}e^{-}âη+X, normalized by the total cross section of e^{+}e^{-}âhadrons, is measured at eight center-of-mass energy points from 2.0000 to 3.6710 GeV. These are the first measurements with momentum dependence in this energy region. Our measurement shows a significant discrepancy compared to the existing fragmentation functions. To address this discrepancy, a new QCD analysis is performed at the next-to-next-to-leading order with hadron mass corrections and higher twist effects, which can explain both the established high-energy data and our measurements reasonably well.
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Objective: To investigate the clinical efficacy of letrozole combined with gonadotropin-releasing hormone antagonists (GnRH-ant) in patients at high risk of ovarian hyperstimulation syndrome (OHSS) who underwent total embryo freezing after oocyte retrieval. Methods: A retrospective analysis was conducted on 348 female patients who underwent in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) at the Reproductive and Genetic Hospital of the First Affiliated Hospital of Zhengzhou University between January and July 2023. Due to their high risk of OHSS, these patients canceled fresh embryo transfer and opted for total embryo freezing. Based on patients' preferences, those who received GnRH-ant and letrozole after oocyte retrieval were categorized as the intervention group (164 cases), while those who did not receive these medications were categorized as the control group (184 cases). The first luteal phase after oocyte retrieval, OHSS grading, ovarian volume, and estradiol (E2) levels were evaluated in both groups. A multivariate logistic regression model was used to analyze factors related to moderate-to-severe OHSS among patients at high risk of OHSS who underwent total embryo freezing after oocyte retrieval. Results: The age of the intervention and control groups was (29.3±3.8) and (29.4±4.1) years, respectively (P=0.821). The duration of the first luteal phase post-oocyte retrieval was shorter in the intervention group [(7.16±1.39) days] compared to that in the control group [(13.88±2.11) days] (P<0.001). The incidences of mild, moderate, and severe OHSS in the intervention group were 75.0% (123 cases), 23.8% (39 cases), and 1.2% (2 cases), respectively, whereas in the control group they were 12.5% (23 cases), 60.9% (112 cases), and 26.6% (49 cases) (P<0.001). E2 levels on the 2nd and 6th days after oocyte retrieval [M(Q1,Q3)] in the intervention group were 1 520.0 (1 213.8, 1 884.8) and 108.5 (45.6, 218.0) ng/L, respectively, which were statistically significantly lower than those in the control group [1 666.0 (508.8, 1 702.0) ng/L] and [1 761.0 (826.0, 2 546.5) ng/L] (P<0.001). The abdominal cavity effusion in the intervention group [M(Q1,Q3)] were 19.5 (0, 30) and 0 mm, statistically significantly less than those in the control group [46.0 (0, 61.0) mm] and [54.5 (0, 69.5) mm] (P<0.001). On the 6th day after oocyte retrieval, the bilateral ovarian volumes in the intervention group were smaller than those in the control group (P<0.001). Multivariate logistic regression analysis indicated that no combined treatment with letrozole and GnRH-ant was a risk factor of moderate to severe OHSS. The risk of developing moderate to severe OHSS in the control group was 35.312 times higher than that in the intervention group (OR=35.312, 95%CI: 17.488-71.300). Conclusions: The administration of letrozole combined with GnRH-ant post-oocyte retrieval in patients at high risk of OHSS can prevent the occurrence of moderate-to-severe OHSS, shorten the first luteal phase, accelerate the reduction of serum E2 levels, and promote the recovery of ovarian volume and absorption of abdominal fluid.
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Fertilização in vitro , Hormônio Liberador de Gonadotropina , Letrozol , Síndrome de Hiperestimulação Ovariana , Humanos , Feminino , Estudos Retrospectivos , Adulto , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/análogos & derivados , Criopreservação , Gravidez , Indução da Ovulação/métodos , Recuperação de Oócitos , Injeções de Esperma Intracitoplásmicas , Taxa de Gravidez , Transferência Embrionária , Antagonistas de Hormônios/uso terapêuticoRESUMO
We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over â]+p[over â] 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 0.02Assuntos
Alimentos
, Fótons
, Movimento (Física)
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Using data samples with an integrated luminosity of 5.85 fb^{-1} collected at center-of-mass energies from 4.61 to 4.95 GeV with the BESIII detector operating at the BEPCII storage ring, we measure the cross section for the process e^{+}e^{-}âK^{+}K^{-}J/ψ. A new resonance with a mass of M=4708_{-15}^{+17}±21 MeV/c^{2} and a width of Γ=126_{-23}^{+27}±30 MeV is observed in the energy-dependent line shape of the e^{+}e^{-}âK^{+}K^{-}J/ψ cross section with a significance over 5σ. The K^{+}J/ψ system is also investigated to search for charged charmoniumlike states, but no significant Z_{cs}^{+} states are observed. Upper limits on the Born cross sections for e^{+}e^{-}âK^{-}Z_{cs}(3985)^{+}/K^{-}Z_{cs}(4000)^{+}+c.c. with Z_{cs}(3985)^{±}/Z_{cs}(4000)^{±}âK^{±}J/ψ are reported at 90% confidence levels. The ratio of branching fractions {[B(Z_{cs}(3985)^{+}âK^{+}J/ψ)]/B[Z_{cs}(3985)^{+}â(D[over ¯]^{0}D_{s}^{*+}+D[over ¯]^{*0}D_{s}^{+})]} is measured to be less than 0.03 at 90% confidence level.
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In the present study, the participation of protein kinase C (PKC) signalling in prothoracicotropic hormone (PTTH)-stimulated ecdysteroidogenesis in Bombyx prothoracic glands (PGs) is demonstrated and characterized. PTTH stimulated phosphorylation of a 37-kDa protein in Bombyx PGs both in vitro and in vivo, as recognized by a PKC substrate antibody. Treatment with either A23187 or thapsigargin also stimulated this 37-kDa protein phosphorylation. PTTH-stimulated phosphorylation of the 37-kDa protein was markedly attenuated in the absence of Ca2+ . The phospholipase C (PLC) inhibitor, U73122, greatly inhibited PTTH-stimulated phosphorylation of this protein, indicating the involvement of Ca2+ and PLC. A mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor (U0126), a phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) and a chemical activator of adenosine 5'-monophosphate-activated protein kinase (AMPK) (5-aminoimidazole-4-carboxamide-1-ß-d-ribofuranoside) did not affect PTTH-stimulated phosphorylation of the 37-kDa protein, implying that ERK and PI3K/AMPK are not the upstream signalling pathways for PKC-dependent protein phosphorylation. The mitochondrial oxidative phosphorylation inhibitors (the uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone and diphenylene iodonium) inhibited PTTH-stimulated phosphorylation of the 37-kDa protein, indicating its redox regulation. Treatment with PKC inhibitors (either calphostin C, chelerythrine C or rottlerin) reduced PTTH-stimulated phosphorylation of the 37-kDa protein. PTTH-stimulated ecdysteroidogenesis was also inhibited by treatment with rottlerin, thus further confirming participation of PKC-dependent phosphorylation in PTTH signalling. From these results, we demonstrated that redox-regulated PTTH-stimulated PKC signalling is involved in ecdysteroid secretion in Bombyx PGs.
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Bombyx , Hormônios de Inseto , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Bombyx/metabolismo , Ecdisteroides/metabolismo , Hormônios de Inseto/metabolismo , Larva/metabolismo , Fosfatidilinositol 3-Quinases , Inibidores de Fosfoinositídeo-3 Quinase , Proteína Quinase C/metabolismoRESUMO
It is well known that phosphorylation of extracellular signal-regulated kinase (ERK) is involved in prothoracicotropic hormone (PTTH)-stimulated ecdysteroidogenesis in insect prothoracic glands (PGs). In the present study, we further investigated the downstream signalling pathways. Our results showed that PTTH stimulated p90 ribosomal S6 kinase (RSK) phosphorylation at Thr573 in Bombyx mori PGs both in vitro and in vivo. The in vitro PTTH stimulation was stage- and dose-dependent. The absence of Ca2+ reduced PTTH-stimulated RSK phosphorylation. Stimulation of RSK phosphorylation was also observed after treatment with either A23187 or thapsigargin. A phospholipase C (PLC) inhibitor, U73122, blocked PTTH-stimulated RSK phosphorylation. These results indicate the involvement of Ca2+ and PLC. Treatment with diphenylene iodonium (DPI), a mitochondrial oxidative phosphorylation inhibitor, blocked PTTH-regulated RSK phosphorylation, indicating its redox regulation. A mitogen-activated protein kinase (MAPK)/ERK kinase (MEK) inhibitor, U0126, but not a phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002, decreased PTTH-stimulated RSK phosphorylation, indicating that ERK is an upstream signalling. A protein kinase C (PKC) inhibitor, chelerythrine C, inhibited PTTH-stimulated RSK phosphorylation, and a PKC activator, phorbol 12-myristate acetate (PMA) stimulated RSK phosphorylation, indicating the involvement of PKC. BI-D1870, a specific RSK inhibitor, partly prevented PTTH-stimulated RSK phosphorylation and significantly inhibited PTTH-stimulated ecdysteroid secretion, indicating that PTTH-stimulated RSK phosphorylation is involved in ecdysteroidogenesis. Taken together, these data indicate that PTTH activates RSK phosphorylation which plays important roles in PTTH-stimulated ecdysteroidogenesis.
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Bombyx , Ecdisona/metabolismo , Hormônios de Inseto/farmacologia , Proteínas Quinases S6 Ribossômicas 90-kDa/química , Animais , Bombyx/metabolismo , Ecdisteroides/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Larva/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , FosforilaçãoRESUMO
The high temperatures and strong magnetic fields of the solar corona form streams of solar wind that expand through the Solar System into interstellar space. At 09:33 UT on 28 April 2021 Parker Solar Probe entered the magnetized atmosphere of the Sun 13 million km above the photosphere, crossing below the Alfvén critical surface for five hours into plasma in casual contact with the Sun with an Alfvén Mach number of 0.79 and magnetic pressure dominating both ion and electron pressure. The spectrum of turbulence below the Alfvén critical surface is reported. Magnetic mapping suggests the region was a steady flow emerging on rapidly expanding coronal magnetic field lines lying above a pseudostreamer. The sub-Alfvénic nature of the flow may be due to suppressed magnetic reconnection at the base of the pseudostreamer, as evidenced by unusually low densities in this region and the magnetic mapping.
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ANITA's fourth long-duration balloon flight in 2016 detected 29 cosmic-ray (CR)-like events on a background of 0.37_{-0.17}^{+0.27} anthropogenic events. CRs are mainly seen in reflection off the Antarctic ice sheets, creating a phase-inverted waveform polarity. However, four of the below-horizon CR-like events show anomalous noninverted polarity, a p=5.3×10^{-4} chance if due to background. All anomalous events are from locations near the horizon; ANITA-IV observed no steeply upcoming anomalous events similar to the two such events seen in prior flights.
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Pain management is an important issue which impacts the prognosis of neonates in neonatal intensive care units. Evidence has shown that professionals' knowledge and attitudes regarding pain management can impact the quality of their practice. The purpose of this study was to evaluate the knowledge, attitudes, and practices of neonatal professionals regarding neonatal pain management. A cross-sectional study was performed involving neonatal physicians and nurses, using a research questionnaire to investigate the knowledge and attitudes of professionals as well as to assess their practice of pain management. Research found an apparent discrepancy between the knowledge levels of neonatologists and nurses regarding pain assessment and management, with nurses displaying weaker professional knowledge and more negative attitudes toward pain management than did neonatologists. Additionally, research revealed a lack of knowledge and negative attitudes among participants regarding the provision of sufficient opioid analgesics to sick infants during invasive procedures and even for dying neonates. There is an urgent need for continuing education regarding neonatal pain management with the goal of empowering neonatal professionals; further research is needed into the question of how to translate education into more reliable practice.Conclusion: This research provides useful information regarding the knowledge, attitudes, and clinical practice of neonatal pain management among neonatologists and nurses and points out some differences in the knowledge levels of these two groups. What is Known: â¢Neonates can perceive and respond to pain stimuli by showing their biological signals similarly to children and adults. â¢Untreated or insufficient pain management for high-risk neonates has short-term. negative effects and may also induce long-term negative effects. What is New: â¢The level of knowledge, the attitudes, and the practices regarding neonatal pain in intensive care are different among neonatal professionals. â¢There is an urgent need to provide interdisciplinary continuing education to improve the knowledge of neonatal professionals and encourage them to more highly prioritize neonatal pain management.
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Conhecimentos, Atitudes e Prática em Saúde , Manejo da Dor , Adulto , Atitude do Pessoal de Saúde , Criança , Estudos Transversais , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Neonatologistas , Inquéritos e QuestionáriosRESUMO
Taiwan had been using many important public health management strategies to beat Coronavirus disease 2019 (COVID-19) without a lockdown. Mask wearing by the general public was thought to be the major factor for the success of Taiwan to stop the spread of COVID-19. We share our experience in Taiwan as an example for other countries to safely reopen from a lockdown.
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This corrects the article DOI: 10.1103/PhysRevLett.109.152301.
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This study investigates the incidences and predictors of hepatitis B virus (HBV) relapse after tenofovir disoproxil fumarate (TDF) therapy in hepatitis B e antigen (HBeAg)-positive and -negative patients. We retrospectively recruited 143 chronic hepatitis B (CHB) patients without cirrhosis (39 HBeAg-positive and 104 HBeAg-negative patients) who were previously treated with TDF and had post-treatment follow-up for at least 6 months (median: 55, IQR 36-85 weeks). All the patients fulfilled the stopping criteria of APASL 2012. The virological and clinical relapse rates at 104 weeks in HBeAg-positive patients were 66.6% and 59.1%, while they were 72.3% and 55.9%, respectively, in HBeAg-negative patients. Cox regression analysis revealed that the higher end-of-treatment HBsAg levels were an independent factor of virological relapse in HBeAg-positive and HBeAg-negative patients. The end-of-treatment HBsAg levels of 200 (area under the receiver operating characteristic (AUROC): 0.624) and 80 IU/mL (AUROC: 0.959) were the optimal values for predicting HBV relapse in HBeAg-positive and HBeAg-negative patients, respectively. The virological relapse rate at 78 weeks was 14.3% and 19.6% in HBeAg-positive and HBeAg-negative patients who achieved HBsAg ≤200 IU/mL and HBsAg ≤80 IU/mL, respectively. Two patients experienced hepatic decompensation upon hepatitis flares, and no patient died after timely retreatment. Seven patients experienced off-therapy HBsAg loss. The cumulative rates of HBsAg loss at 104 weeks were 45.5% and 59.3% in patients with end-of-treatment HBsAg ≤80 IU/mL and ≤50 IU/mL, respectively. In conclusions, the end-of-treatment HBsAg levels were a useful marker for predicting HBV relapse in HBeAg-positive and HBeAg-negative CHB patients.
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Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/epidemiologia , Tenofovir/uso terapêutico , Adulto , Idoso , Feminino , Seguimentos , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/patologia , Hepatite B Crônica/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Medição de RiscoRESUMO
Fracture liaison services (FLS) have been demonstrated to improve outcomes following osteoporotic fracture. The aim of this systematic literature review (SLR) was to determine the characteristics of an FLS that lead to improved patient outcomes. We conducted a SLR, including articles published between 2000 and February 2017, using global (Medline, EMBASE, PubMed and Cochrane Library) and local databases. Studies including patients aged ≥ 50 years with osteoporotic fractures enrolled in an FLS were assessed. Information extracted from each article included key person coordinating the FLS (physician, nurse or other healthcare professional), setting (hospital vs community), intensity (single vs multiple), duration (long vs short term), fracture type and gender. A meta-analysis of randomised controlled trials was conducted based on the key person coordinating the FLS. Out of 7236 articles, 57 were considered to be high quality and identified for further analysis. The SLR identified several components which contributed to FLS success, including multidisciplinary involvement, driven by a dedicated case manager, regular assessment and follow-up, multifaceted interventions and patient education. Meta-analytic data confirm the effectiveness of an FLS following an osteoporotic fracture: approximate 27% increase in the likelihood of BMD testing and up to 21% increase in the likelihood of treatment initiation compared with usual care. The balance of evidence indicates that the multifaceted FLS and dedicated coordination are important success factors that contribute to effective FLS interventions which reduce fracture-related morbidity and mortality.
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Prestação Integrada de Cuidados de Saúde/organização & administração , Fraturas por Osteoporose/prevenção & controle , Prevenção Secundária/organização & administração , Conservadores da Densidade Óssea/uso terapêutico , Humanos , Osteoporose/diagnóstico , Osteoporose/tratamento farmacológico , Indicadores de Qualidade em Assistência à SaúdeRESUMO
Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.
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We report on an upward traveling, radio-detected cosmic-ray-like impulsive event with characteristics closely matching an extensive air shower. This event, observed in the third flight of the Antarctic Impulsive Transient Antenna (ANITA), a NASA-sponsored long-duration balloon payload, is consistent with a similar event reported in a previous flight. These events could be produced by the atmospheric decay of an upward-propagating τ lepton produced by a ν_{τ} interaction, although their relatively steep arrival angles create tension with the standard model neutrino cross section. Each of the two events have a posteriori background estimates of â²10^{-2} events. If these are generated by τ-lepton decay, then either the charged-current ν_{τ} cross section is suppressed at EeV energies, or the events arise at moments when the peak flux of a transient neutrino source was much larger than the typical expected cosmogenic background neutrinos.