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1.
S Afr Med J ; 114(2): e1538, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38525575

RESUMO

Determining the death burden for prioritising public health interventions necessitates detailed data on the causal pathways to death. Postmortem minimally invasive tissue sampling (MITS), incorporating histology, molecular and microbial culture diagnostics, enhances cause-of-death attribution, particularly for infectious deaths. MITS proves a valid alternative to full diagnostic autopsies, especially in low- and middle-income countries. In Soweto, South Africa (SA), the Child Health and Mortality Prevention Surveillance (CHAMPS) programme has delineated over 1 000 child and stillbirth deaths since 2017. This SA CHAMPS site supports advocating for the use of postmortem MITS as routine practice, for more granular insights into under-5 mortality causes. This knowledge is crucial for SA's pursuit of Sustainable Development Goal 3.2, targeting reduced neonatal and under-5 mortality rates. This commentary explores the public health advantages and ethicolegal considerations surrounding implementing MITS as standard of care for stillbirths, neonatal and paediatric deaths in SA. Furthermore, based on the data from CHAMPS, we present three pragmatic algorithmic approaches to the wide array of testing options for cost-effectiveness and scalability of postmortem MITS in South African state facilities.


Assuntos
Mortalidade da Criança , Padrão de Cuidado , Criança , Recém-Nascido , Gravidez , Feminino , Humanos , África do Sul , Causas de Morte , Natimorto , Autopsia
2.
Schweiz Arch Tierheilkd ; 164(10): 733-739, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36193783

RESUMO

INTRODUCTION: Outbreaks of equine coronavirus (ECoV) infections have been described in different parts of the world including Europe. The aim of this report was to describe clinical signs, diagnostic work-up and outcome of the first documented outbreak of ECoV in Switzerland in order to raise the awareness for the disease and its various clinical presentations. The outbreak occurred on a farm with 26 horses. Of these, seven horses developed clinical disease ranging from mild signs such as fever and anorexia to severe signs of acute colitis. One horse died due to severe endotoxemia and circulatory shock secondary to severe acute necrotizing enteritis and colitis. Out of the 26 horses, five horses tested positive for ECoV, including two ponies without any clinical signs of infection. The low number of positive cases should nevertheless be interpreted with caution as testing was only performed on one occasion, over a month after the onset of clinical signs in the first suspected case. This report highlights the importance of diagnostic testing and early implementation of biosecurity measures on a farm with an ECoV outbreak. It should furthermore raise the awareness for unspecific and mild clinical signs such as fever and anorexia in affected animals that are potentially able to spread the disease.


INTRODUCTION: Des foyers d'infection à coronavirus équin (ECoV) ont été décrits dans différentes parties du monde, y compris en Europe. L'objectif de ce rapport est de décrire les signes cliniques, le diagnostic et les conséquences du premier foyer d'ECoV documenté en Suisse, afin de sensibiliser le public à cette maladie et à ses différents aspects cliniques. L'épidémie s'est produite dans une écurie comptant 26 chevaux. Parmi ceux-ci, sept chevaux ont développé une forme clinique allant de signes légers tels que la fièvre et l'anorexie à des signes sévères de colite aiguë. Un cheval est mort en raison d'une endotoxémie sévère et d>un choc circulatoire secondaire à une entérite nécrosante aiguë sévère et à une colite. Sur les 26 chevaux, cinq ont été testés positifs à l>ECoV, dont deux poneys sans aucun signe clinique d'infection. Le faible nombre de cas positifs doit néanmoins être interprété avec prudence car les tests n'ont été effectués qu'à une seule occasion, plus d'un mois après l'apparition des signes cliniques chez le premier cas suspect. Ce rapport souligne l'importance des tests de diagnostic et de la mise en œuvre rapide de mesures de biosécurité dans une exploitation où un foyer d'ECoV est détecté. Il devrait en outre sensibiliser à la présence de signes cliniques peu spécifiques et bénins tels que la fièvre et l'anorexie chez les animaux atteints qui sont potentiellement capables de propager la maladie.


Assuntos
Betacoronavirus 1 , Colite , Infecções por Coronavirus , Doenças dos Cavalos , Animais , Anorexia/veterinária , Colite/epidemiologia , Colite/veterinária , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Surtos de Doenças/veterinária , Fezes , Doenças dos Cavalos/diagnóstico , Cavalos , Suíça/epidemiologia
3.
Phys Rev Lett ; 127(16): 162001, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34723614

RESUMO

Studying spin-momentum correlations in hadronic collisions offers a glimpse into a three-dimensional picture of proton structure. The transverse single-spin asymmetry for midrapidity isolated direct photons in p^{↑}+p collisions at sqrt[s]=200 GeV is measured with the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). Because direct photons in particular are produced from the hard scattering and do not interact via the strong force, this measurement is a clean probe of initial-state spin-momentum correlations inside the proton and is in particular sensitive to gluon interference effects within the proton. This is the first time direct photons have been used as a probe of spin-momentum correlations at RHIC. The uncertainties on the results are a 50-fold improvement with respect to those of the one prior measurement for the same observable, from the Fermilab E704 experiment. These results constrain gluon spin-momentum correlations in transversely polarized protons.

5.
Phys Rev Lett ; 123(12): 122001, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31633981

RESUMO

We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively charged hadrons in polarized p^{↑}+p, p^{↑}+Al, and p^{↑}+Au collisions at sqrt[s_{NN}]=200 GeV. The measurements have been performed at forward rapidity (1.4<η<2.4) over the range of transverse momentum (1.8

6.
Phys Rev Lett ; 121(22): 222301, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547634

RESUMO

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.

7.
Phys Rev Lett ; 120(6): 062302, 2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29481251

RESUMO

Recently, multiparticle-correlation measurements of relativistic p/d/^{3}He+Au, p+Pb, and even p+p collisions show surprising collective signatures. Here, we present beam-energy-scan measurements of two-, four-, and six-particle angular correlations in d+Au collisions at sqrt[s_{NN}]=200, 62.4, 39, and 19.6 GeV. We also present measurements of two- and four-particle angular correlations in p+Au collisions at sqrt[s_{NN}]=200 GeV. We find the four-particle cumulant to be real valued for d+Au collisions at all four energies. We also find that the four-particle cumulant in p+Au has the opposite sign as that in d+Au. Further, we find that the six-particle cumulant agrees with the four-particle cumulant in d+Au collisions at 200 GeV, indicating that nonflow effects are subdominant. These observations provide strong evidence that the correlations originate from the initial geometric configuration, which is then translated into the momentum distribution for all particles, commonly referred to as collectivity.

8.
Phys Rev Lett ; 120(2): 022001, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376675

RESUMO

During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polarized p+p collisions at RHIC, and the existing theoretical framework that was successful in describing the single-spin asymmetry in p+p collisions predicts only a moderate atomic-mass-number (A) dependence. In contrast, the asymmetries observed at RHIC in p+A collisions showed a surprisingly strong A dependence in inclusive forward neutron production. The observed asymmetry in p+Al collisions is much smaller, while the asymmetry in p+Au collisions is a factor of 3 larger in absolute value and of opposite sign. The interplay of different neutron production mechanisms is discussed as a possible explanation of the observed A dependence.

9.
Phys Rev Lett ; 116(12): 122301, 2016 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-27058071

RESUMO

Jet production rates are measured in p+p and d+Au collisions at sqrt[s_{NN}]=200 GeV recorded in 2008 with the PHENIX detector at the Relativistic Heavy Ion Collider. Jets are reconstructed using the R=0.3 anti-k_{t} algorithm from energy deposits in the electromagnetic calorimeter and charged tracks in multiwire proportional chambers, and the jet transverse momentum (p_{T}) spectra are corrected for the detector response. Spectra are reported for jets with 12

10.
Phys Rev Lett ; 114(19): 192301, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024164

RESUMO

We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sqrt[s_{NN}]=200 GeV. The charged hadron is measured at midrapidity |η|<0.35, and the energy is measured at large rapidity (-3.7<η<-3.1, Au-going direction). An enhanced near-side angular correlation across |Δη|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v_{2} for inclusive charged hadrons at midrapidity up to p_{T}=4.5 GeV/c. We also present the measurement of v_{2} for identified π^{±} and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sqrt[s_{NN}]=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

11.
Am J Transplant ; 14(11): 2633-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25250717

RESUMO

We describe two cases of donor-derived methicillin-resistant Staphylococcus aureus (MRSA) bacteremia that developed after transplantation of organs from a common donor who died from acute MRSA endocarditis. Both recipients developed recurrent MRSA infection despite appropriate antibiotic therapy, and required prolonged hospitalization and hospital readmission. Comparison of S. aureus whole genome sequence of DNA extracted from fixed donor tissue and recipients' isolates confirmed donor-derived transmission. Current guidelines emphasize the risk posed by donors with bacteremia from multidrug-resistant organisms. This investigation suggests that, particularly in the setting of donor endocarditis, even a standard course of prophylactic antibiotics may not be sufficient to prevent donor-derived infection.


Assuntos
Genoma Bacteriano , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Transplante de Órgãos/efeitos adversos , Análise de Sequência de DNA , Infecções Estafilocócicas/transmissão , Doadores de Tecidos , DNA Bacteriano/genética , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Polimorfismo de Nucleotídeo Único , Infecções Estafilocócicas/microbiologia
12.
Phys Rev Lett ; 112(25): 252301, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-25014805

RESUMO

The PHENIX experiment has measured open heavy-flavor production via semileptonic decay over the transverse momentum range 1 < p(T) < 6 GeV/c at forward and backward rapidity (1.4 < |y| < 2.0) in d+Au and p + p collisions at √sNN = 200 GeV. In central d+Au collisions, relative to the yield in p + p collisions scaled by the number of binary nucleon-nucleon collisions, a suppression is observed at forward rapidity (in the d-going direction) and an enhancement at backward rapidity (in the Au-going direction). Predictions using nuclear-modified-parton-distribution functions, even with additional nuclear-p(T) broadening, cannot simultaneously reproduce the data at both rapidity ranges, which implies that these models are incomplete and suggests the possible importance of final-state interactions in the asymmetric d + Au collision system. These results can be used to probe cold-nuclear-matter effects, which may significantly affect heavy-quark production, in addition to helping constrain the magnitude of charmonia-breakup effects in nuclear matter.

13.
Phys Rev Lett ; 111(20): 202301, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24289677

RESUMO

We present results for three charmonia states (ψ', χc, and J/ψ) in d+Au collisions at |y|<0.35 and sqrt[s(NN)]=200 GeV. We find that the modification of the ψ' yield relative to that of the J/ψ scales approximately with charged particle multiplicity at midrapidity across p+A, d+Au, and A+A results from the Super Proton Synchrotron and the Relativistic Heavy Ion Collider. In large-impact-parameter collisions we observe a similar suppression for the ψ' and J/ψ, while in small-impact-parameter collisions the more weakly bound ψ' is more strongly suppressed. Owing to the short time spent traversing the Au nucleus, the larger ψ' suppression in central events is not explained by an increase of the nuclear absorption owing to meson formation time effects.

14.
Phys Rev Lett ; 111(21): 212301, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24313481

RESUMO

The PHENIX collaboration at the Relativistic Heavy Ion Collider (RHIC) reports measurements of azimuthal dihadron correlations near midrapidity in d+Au collisions at √(s(NN))=200 GeV. These measurements complement recent analyses by experiments at the Large Hadron Collider (LHC) involving central p+Pb collisions at √(s(NN))=5.02 TeV, which have indicated strong anisotropic long-range correlations in angular distributions of hadron pairs. The origin of these anisotropies is currently unknown. Various competing explanations include parton saturation and hydrodynamic flow. We observe qualitatively similar, but larger, anisotropies in d+Au collisions at RHIC compared to those seen in p+Pb collisions at the LHC. The larger extracted v2 values in d+Au are consistent with expectations from hydrodynamic calculations owing to the larger expected initial-state eccentricity compared with that from p+Pb collisions. When both are divided by an estimate of the initial-state eccentricity the scaled anisotropies follow a common trend with multiplicity that may extend to heavy ion data at RHIC and the LHC, where the anisotropies are widely thought to arise from hydrodynamic flow.

15.
Phys Rev Lett ; 111(3): 032301, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23909311

RESUMO

The jet fragmentation function is measured with direct photon-hadron correlations in p+p and Au+Au collisions at √[s(NN)]=200 GeV. The p(T) of the photon is an excellent approximation to the initial p(T) of the jet and the ratio z(T)=p(T)(h)/p(T)(γ) is used as a proxy for the jet fragmentation function. A statistical subtraction is used to extract the direct photon-hadron yields in Au+Au collisions while a photon isolation cut is applied in p+p. I(AA), the ratio of hadron yield opposite the photon in Au+Au to that in p+p, indicates modification of the jet fragmentation function. Suppression, most likely due to energy loss in the medium, is seen at high z(T). The associated hadron yield at low z(T) is enhanced at large angles. Such a trend is expected from redistribution of the lost energy into increased production of low-momentum particles.

17.
Phys Rev Lett ; 109(24): 242301, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23368311

RESUMO

The PHENIX experiment has measured electrons and positrons at midrapidity from the decays of hadrons containing charm and bottom quarks produced in d+Au and p+p collisions at sqrt[S(NN)]=200 GeV in the transverse-momentum range 0.85 ≤ p(T)(e) ≤ 8.5 GeV/c. In central d+Au collisions, the nuclear modification factor R(dA) at 1.5

18.
Phys Rev Lett ; 107(14): 142301, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-22107186

RESUMO

We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200 GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2

19.
Phys Rev Lett ; 107(17): 172301, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22107509

RESUMO

Back-to-back hadron pair yields in d+Au and p+p collisions at √s(NN)=200 GeV were measured with the PHENIX detector at the Relativistic Heavy Ion Collider. Rapidity separated hadron pairs were detected with the trigger hadron at pseudorapidity |η|<0.35 and the associated hadron at forward rapidity (deuteron direction, 3.0<η<3.8). Pairs were also detected with both hadrons measured at forward rapidity; in this case, the yield of back-to-back hadron pairs in d+Au collisions with small impact parameters is observed to be suppressed by a factor of 10 relative to p+p collisions. The kinematics of these pairs is expected to probe partons in the Au nucleus with a low fraction x of the nucleon momenta, where the gluon densities rise sharply. The observed suppression as a function of nuclear thickness, p(T), and η points to cold nuclear matter effects arising at high parton densities.

20.
Phys Rev Lett ; 106(6): 062001, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21405459

RESUMO

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = -0.86(-0.14) (+0.30) and A(L)(e-) = 0.88(-0.71) (+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p+p collisions at a center-of-mass energy of sqrt[s] = 500 GeV with the PHENIX detector at RHIC. These e± come mainly from the decay of W± and Z0 bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W± to the light quarks. The observed electron and positron yields were used to estimate W± boson production cross sections for the e± channels of σ(pp → W+ X) × BR(W+ → e+ ν(e)) = 144.1 ± 21.2(stat)(-10.3) (+3.4) (syst) ± 21.6(norm) pb, and σ(pp → W- X) × BR(W- → e- ν[over ¯](e)) = 31.7 ± 12.1(stat)(-8.2) (+10.1) (syst) ± 4.8(norm) pb.

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