Hyperon Polarization along the Beam Direction Relative to the Second and Third Harmonic Event Planes in Isobar Collisions at sqrt[s_{NN}]=200 GeV

The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200  GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.

Erratum: Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV [Phys. Rev. Lett. 126, 162301 (2021)]

This corrects the article DOI: 10.1103/PhysRevLett.126.162301.

Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central ^{3}He+Au, d+Au and p+Au Collisions at sqrt[s_{NN}]=200 GeV

The elliptic (v_{2}) and triangular (v_{3}) azimuthal anisotropy coefficients in central ^{3}He+Au, d+Au, and p+Au collisions at sqrt[s_{NN}]=200  GeV are measured as a function of transverse momentum (p_{T}) at midrapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v_{2}(p_{T}) values depend on the colliding systems, the v_{3}(p_{T}) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.

Observation of Directed Flow of Hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in sqrt[s_{NN}]=3 GeV Au+Au Collisions at RHIC

We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3  GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.

Beam Energy Dependence of Triton Production and Yield Ratio (N_{t}×N_{p}/N_{d}^{2}) in Au+Au Collisions at RHIC

We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrt[s_{NN}]=7.7-200  GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.

Measurement of Sequential ϒ Suppression in Au+Au Collisions at sqrt[s_{NN}]=200 GeV with the STAR Experiment

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200  GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

Beam Energy Dependence of Fifth- and Sixth-Order Net-Proton Number Fluctuations in Au+Au Collisions at RHIC

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, μ_{B}≤110  MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, μ_{B}∼750  MeV at sqrt[s_{NN}]=3  GeV is starkly different from those at vanishing μ_{B}∼24  MeV at sqrt[s_{NN}]=200  GeV and higher collision energies.

Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations

Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193  GeV, Cu+Au at sqrt[s_{NN}]=200  GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200  GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point

We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0  GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0  GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.

Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0  GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0  GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst)  ps for _{Λ}^{3}H and 218±6(stat)±13(syst)  ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

Probing the Gluonic Structure of the Deuteron with J/ψ Photoproduction in d+Au Ultraperipheral Collisions

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200  GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.

Search for the Chiral Magnetic Effect via Charge-Dependent Azimuthal Correlations Relative to Spectator and Participant Planes in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

The chiral magnetic effect (CME) refers to charge separation along a strong magnetic field due to imbalanced chirality of quarks in local parity and charge-parity violating domains in quantum chromodynamics. The experimental measurement of the charge separation is made difficult by the presence of a major background from elliptic azimuthal anisotropy. This background and the CME signal have different sensitivities to the spectator and participant planes, and could thus be determined by measurements with respect to these planes. We report such measurements in Au+Au collisions at a nucleon-nucleon center-of-mass energy of 200 GeV at the Relativistic Heavy-Ion Collider. It is found that the charge separation, with the flow background removed, is consistent with zero in peripheral (large impact parameter) collisions. Some indication of finite CME signals is seen in midcentral (intermediate impact parameter) collisions. Significant residual background effects may, however, still be present.

Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

Observation of D_{s}^{±}/D^{0} Enhancement in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of charm-strange meson D_{s}^{±} production at midrapidity in Au+Au collisions at sqrt[s_{NN}]=200  GeV from the STAR experiment. The yield ratio between strange (D_{s}^{±}) and nonstrange (D^{0}) open-charm mesons is presented and compared to model calculations. A significant enhancement, relative to a pythia simulation of p+p collisions, is observed in the D_{s}^{±}/D^{0} yield ratio in Au+Au collisions over a large range of collision centralities. Model calculations incorporating abundant strange-quark production in the quark-gluon plasma and coalescence hadronization qualitatively reproduce the data. The transverse-momentum integrated yield ratio of D_{s}^{±}/D^{0} at midrapidity is consistent with a prediction from a statistical hadronization model with the parameters constrained by the yields of light and strange hadrons measured at the same collision energy. These results suggest that the coalescence of charm quarks with strange quarks in the quark-gluon plasma plays an important role in D_{s}^{±}-meson production in heavy-ion collisions.

Measurement of e^{+}e^{-} Momentum and Angular Distributions from Linearly Polarized Photon Collisions

The Breit-Wheeler process which produces matter and antimatter from photon collisions is experimentally investigated through the observation of 6085 exclusive electron-positron pairs in ultraperipheral Au+Au collisions at sqrt[s_{NN}]=200  GeV. The measurements reveal a large fourth-order angular modulation of cos4Δϕ=(16.8±2.5)% and smooth invariant mass distribution absent of vector mesons (ϕ, ω, and ρ) at the experimental limit of ≤0.2% of the observed yields. The differential cross section as a function of e^{+}e^{-} pair transverse momentum P_{⊥} peaks at low value with sqrt[⟨P_{⊥}^{2}⟩]=38.1±0.9  MeV and displays a significant centrality dependence. These features are consistent with QED calculations for the collision of linearly polarized photons quantized from the extremely strong electromagnetic fields generated by the highly charged Au nuclei at ultrarelativistic speed. The experimental results have implications for vacuum birefringence and for mapping the magnetic field which is important for emergent QCD phenomena.

Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

Global polarization of Ξ and Ω hyperons has been measured for the first time in Au+Au collisions at sqrt[s_{NN}]=200  GeV. The measurements of the Ξ^{-} and Ξ[over ¯]^{+} hyperon polarization have been performed by two independent methods, via analysis of the angular distribution of the daughter particles in the parity violating weak decay Ξ→Λ+π, as well as by measuring the polarization of the daughter Λ hyperon, polarized via polarization transfer from its parent. The polarization, obtained by combining the results from the two methods and averaged over Ξ^{-} and Ξ[over ¯]^{+}, is measured to be ⟨P_{Ξ}⟩=0.47±0.10(stat)±0.23(syst)% for the collision centrality 20%-80%. The ⟨P_{Ξ}⟩ is found to be slightly larger than the inclusive Λ polarization and in reasonable agreement with a multiphase transport model. The ⟨P_{Ξ}⟩ is found to follow the centrality dependence of the vorticity predicted in the model, increasing toward more peripheral collisions. The global polarization of Ω, ⟨P_{Ω}⟩=1.11±0.87(stat)±1.97(syst)% was obtained by measuring the polarization of daughter Λ in the decay Ω→Λ+K, assuming the polarization transfer factor C_{ΩΛ}=1.

Nonmonotonic Energy Dependence of Net-Proton Number Fluctuations

Nonmonotonic variation with collision energy (sqrt[s_{NN}]) of the moments of the net-baryon number distribution in heavy-ion collisions, related to the correlation length and the susceptibilities of the system, is suggested as a signature for the quantum chromodynamics critical point. We report the first evidence of a nonmonotonic variation in the kurtosis times variance of the net-proton number (proxy for net-baryon number) distribution as a function of sqrt[s_{NN}] with 3.1  σ significance for head-on (central) gold-on-gold (Au+Au) collisions measured solenoidal tracker at Relativistic Heavy Ion Collider. Data in noncentral Au+Au collisions and models of heavy-ion collisions without a critical point show a monotonic variation as a function of sqrt[s_{NN}].

First Measurement of Λ_{c} Baryon Production in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the first measurement of the charmed baryon Λ_{c}^{±} production at midrapidity (|y|<1) in Au+Au collisions at sqrt[s_{NN}]=200  GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider. The Λ_{c}/D^{0} [denoting (Λ_{c}^{+}+Λ_{c}^{-})/(D^{0}+D[over ¯]^{0})] yield ratio is measured to be 1.08±0.16  (stat)±0.26  (sys) in the 0%-20% most central Au+Au collisions for the transverse momentum (p_{T}) range 3<p_{T}<6  GeV/c. This is significantly larger than the pythia model calculations for p+p collisions. The measured Λ_{c}/D^{0} ratio, as a function of p_{T} and collision centrality, is comparable to the baryon-to-meson ratios for light and strange hadrons in Au+Au collisions. Model calculations including coalescence hadronization for charmed baryon and meson formation reproduce the features of our measured Λ_{c}/D^{0} ratio.

Morphological and molecular evidence support the intertidal barnacle Octomeris intermedia Nilsson-Cantell, 1921 (Thoracica, Chthamalidae) as a valid species in Indo-Pacific waters

Octomeris is a chthamalid intertidal barnacle with eight shell plates. There are currently two species of such barnacles: O. brunnea Darwin, 1854 (type locality in the Philippines), common in the Indo-Pacific region, and O. angulosa Sowerby, 1825, only recorded in South Africa. Octomeris intermedia Nilsson-Cantell, 1921, identified from the Mergui Archipelago in Myanmar, was considered to be conspecific with O. brunnea by Hiro (1939) based on samples collected in Taiwan. The morphological differences in shell and opercular plates between O. brunnea and O. intermedia are believed to be intra-specific variations due to different degrees of shell erosion. In the present study, the genetic and morphological differentiations of Octomeris in the Indo-Pacific region were examined. This study found two molecular clades (with inter-specific differences) based on the divergence in the COI genes, and the species also have distinct geographical distributions. The Octomeris brunnea clade covers samples collected from the Philippines and Taiwan waters and the other clade, which we argue is O. intermedia, is distributed in Phuket and Krabi, Thailand and Langkawi, Malaysia. Phuket and Krabi are located approximately 300 km south of the Mergui Archipelago, the type locality of O. intermedia. The morphology of samples collected from Thailand fits the type description of O. intermedia in Nilsson-Cantell (1921). Our study concludes that O. intermedia is a valid species based on morphological and molecular evidence.

First Observation of the Directed Flow of D^{0} and D^{0}[over ¯] in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

We report the first measurement of rapidity-odd directed flow (v_{1}) for D^{0} and D^{0}[over ¯] mesons at midrapidity (|y|<0.8) in Au+Au collisions at sqrt[s_{NN}]=200  GeV using the STAR detector at the Relativistic Heavy Ion Collider. In 10-80% Au+Au collisions, the slope of the v_{1} rapidity dependence (dv_{1}/dy), averaged over D^{0} and D^{0}[over ¯] mesons, is -0.080±0.017(stat)±0.016(syst) for transverse momentum p_{T} above 1.5  GeV/c. The absolute value of D^{0} meson dv_{1}/dy is about 25 times larger than that for charged kaons, with 3.4σ significance. These data give a unique insight into the initial tilt of the produced matter, and offer constraints on the geometric and transport parameters of the hot QCD medium created in relativistic heavy-ion collisions.

Polarization of Λ (Λ[over ¯]) Hyperons along the Beam Direction in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

The Λ (Λ[over ¯]) hyperon polarization along the beam direction has been measured in Au+Au collisions at sqrt[s_{NN}]=200  GeV, for the first time in heavy-ion collisions. The polarization dependence on the hyperons' emission angle relative to the elliptic flow plane exhibits a second harmonic sine modulation, indicating a quadrupole pattern of the vorticity component along the beam direction, expected due to elliptic flow. The polarization is found to increase in more peripheral collisions, and shows no strong transverse momentum (p_{T}) dependence at p_{T} greater than 1  GeV/c. The magnitude of the signal is about 5 times smaller than those predicted by hydrodynamic and multiphase transport models; the observed phase of the emission angle dependence is also opposite to these model predictions. In contrast, the kinematic vorticity calculations in the blast-wave model tuned to reproduce particle spectra, elliptic flow, and the azimuthal dependence of the Gaussian source radii measured with the Hanbury Brown-Twiss intensity interferometry technique reproduce well the modulation phase measured in the data and capture the centrality and transverse momentum dependence of the polarization signal.

Observation of Excess J/ψ Yield at Very Low Transverse Momenta in Au+Au Collisions at sqrt[s_{NN}]=200 GeV and U+U Collisions at sqrt[s_{NN}]=193 GeV

We report on the first measurements of J/ψ production at very low transverse momentum (p_{T}<0.2  GeV/c) in hadronic Au+Au collisions at sqrt[s_{NN}]=200  GeV and U+U collisions at sqrt[s_{NN}]=193  GeV. Remarkably, the inferred nuclear modification factor of J/ψ at midrapidity in Au+Au (U+U) collisions reaches about 24 (52) for p_{T}<0.05  GeV/c in the 60%-80% collision centrality class. This noteworthy enhancement cannot be explained by hadronic production accompanied by cold and hot medium effects. In addition, the dN/dt distribution of J/ψ for the very low p_{T} range is presented for the first time. The distribution is consistent with that expected from the Au nucleus and shows a hint of interference. Comparison of the measurements to theoretical calculations of coherent production shows that the excess yield can be described reasonably well and reveals a partial disruption of coherent production in semicentral collisions, perhaps due to the violent hadronic interactions. Incorporating theoretical calculations, the results strongly suggest that the dramatic enhancement of J/ψ yield observed at extremely low p_{T} originates from coherent photon-nucleus interactions. In particular, coherently produced J/ψ's in violent hadronic collisions may provide a novel probe of the quark-gluon plasma.

A new species of Synagoga (Crustacea, Thecostraca, Ascothoracida) parasitic in an antipatharian from Green Island, Taiwan, with notes on its morphology

A new ascothoracidan species has been discovered off Taiwan in the north part of the west Pacific at SCUBA depths. Twelve specimens including both sexes of the new species, described herein as Synagoga arabesque sp. nov., were collected from colonies of the antipatharian Myriopathes cf. japonica Brook, 1889. Three previously described species of Synagoga, morphologically the least specialized ascothoracidan genus, have been found as ectoparasites of antipatharians and an alcyonarian, whereas all other records of this genus have been based on specimens collected from the marine plankton. This is the second study of a new form of Synagoga to be based on more than a few mature specimens of a single sex or on a single juvenile. Furthermore, it is the second in which SEM has been used to document the fine-scale external morphology. The position of terminal pores in the anterior pairs of the lattice organs is different in Synagoga arabesque sp. nov. than those in S. grygieri Kolbasov & Newman, 2018 and S. millipalus Grygier & Ohtsuka, 1995. Species of Synagoga are small, host-specific predators or ectoparasites of antipatharians. This genus exhibits a major Tethyan reliction pattern.

Towards a barnacle tree of life: integrating diverse phylogenetic efforts into a comprehensive hypothesis of thecostracan evolution

Barnacles and their allies (Thecostraca) are a biologically diverse, monophyletic crustacean group, which includes both intensely studied taxa, such as the acorn and stalked barnacles, as well as cryptic taxa, for example, Facetotecta. Recent efforts have clarified phylogenetic relationships in many different parts of the barnacle tree, but the outcomes of these phylogenetic studies have not yet been combined into a single hypothesis for all barnacles. In the present study, we applied a new "synthesis" tree approach to estimate the first working Barnacle Tree of Life. Using this approach, we integrated phylogenetic hypotheses from 27 studies, which did not necessarily include the same taxa or used the same characters, with hierarchical taxonomic information for all recognized species. This first synthesis tree contains 2,070 barnacle species and subspecies, including 239 barnacle species with phylogenetic information and 198 undescribed or unidentified species. The tree had 442 bifurcating nodes, indicating that 79.3% of all nodes are still unresolved. We found that the acorn and stalked barnacles, the Thoracica, and the parasitic Rhizocephala have the largest amount of published phylogenetic information. About half of the thecostracan families for which phylogenetic information was available were polyphyletic. We queried publicly available geographic occurrence databases for the group, gaining a sense of geographic gaps and hotspots in our phylogenetic knowledge. Phylogenetic information is especially lacking for deep sea and Arctic taxa, but even coastal species are not fully incorporated into phylogenetic studies.

Azimuthal Harmonics in Small and Large Collision Systems at RHIC Top Energies

The first (v_{1}^{fluc}), second (v_{2}), and third (v_{3}) harmonic coefficients of the azimuthal particle distribution at midrapidity are extracted for charged hadrons and studied as a function of transverse momentum (p_{T}) and mean charged particle multiplicity density ⟨N_{ch}⟩ in U+U (sqrt[s_{NN}]=193  GeV), Au+Au, Cu+Au, Cu+Cu, d+Au, and p+Au collisions at sqrt[s_{NN}]=200  GeV with the STAR detector. For the same ⟨N_{ch}⟩, the v_{1}^{fluc} and v_{3} coefficients are observed to be independent of the collision system, while v_{2} exhibits such a scaling only when normalized by the initial-state eccentricity (ϵ_{2}). The data also show that ln(v_{2}/ϵ_{2}) scales linearly with ⟨N_{ch}⟩^{-1/3}. These measurements provide insight into initial-geometry fluctuations and the role of viscous hydrodynamic attenuation on v_{n} from small to large collision systems.

Enrichment of Retroviral Sequences in Brain Tissue from Patients with Severe Demyelinating Diseases

Background

Our group has used deep sequencing to identify viral RNA signatures in human brain specimens. We have previously used this method to detect HSV1, GBV-C, and measles virus sequence in brain tissue from deceased donors. Deep sequencing was performed on brain specimens from a cohort of patients who died with progressive forms of MS, revealing evidence of increased expression of some human endogenous retrovirus (HERV) domains.

Objectives

Identify RNA sequences and new antigens involved in the pathogenesis of MS

Methods

Deep sequencing was performed on RNA extracted from 12 progressive MS, 2 neuromyelitis optica (MS/NMO = demyelination group), 14 normal control, and 7 other neurologic disease (OND) control frozen brain specimens. The resulting single-ended 50 bp sequences (reads) were compared to a non redundant viral database representing (NRVDB) all 1.2 M viral records in GenBank. A retroviral gene catalog (RVGC) was prepared by identifying human genetic loci (GRCh37.p13) homologous to domains contained in the Gypsy 2.0 retro element database. Reads were aligned to the RVGC and human transcriptome with Bowtie2. The resulting viral hit rates (VHRs) were normalized by the number of high quality reads. The expression of human genes, including HERVs, was determined using Cufflinks. Comparisons between the groups were performed using the false discovery rate.

Results

Fifty to 131 million high quality reads per specimen were obtained. Comparison of the reads to the NRVDB suggested that the demyelination and OND specimens had higher VHRs against some retroviral sequences compared with the controls. This was confirmed by retroviral domain averaging. Gene expression analysis showed differential expression among some HERV sequences. Single read mapping revealed one envelope and one reverse transcriptase sequence record that were significantly enriched among the demyelination samples compared to the normal controls. Less restrictive (comprehensive) read mapping showed that 2 integrase, 2 core, 2 envelope, and 3 KRAB sequences that were overexpressed in the demyelination group.

Conclusions

These data demonstrate that some endogenous retroviral sequences are significantly overexpressed in these demyelination brain tissue specimens, but the magnitude of this overexpression is small. This is consistent with the concept of HERV activation as a part of the innate immune response.

Metamorphosis in balanomorphan, pedunculated, and parasitic barnacles: a video-based analysis

Cypris metamorphosis was followed using video microscopy in four species of cirripeds representing the suspension-feeding pedunculated and sessile Thoracica and the parasitic Rhizocephala. Cirripede metamorphosis involves one or more highly complex molts that mark the change from a free cypris larva to an attached suspension feeder (Thoracica) or an endoparasite (Rhizocephala). The cyprids and juveniles are so different in morphology that they are functionally incompatible. The drastic reorganization of the body implicated in the process can therefore only commence after the cyprid has irreversibly cemented itself to a substratum. In both Megabalanus rosa and Lepas, the settled cyprid first passes through a quiescent period of tissue reorganization, in which the body is raised into a position vertical to the substratum. In Lepas, this is followed by extension of the peduncle. In both Lepas and M. rosa, the juvenile must free itself from the cypris cuticle by an active process before it can extend the cirri for suspension feeding. In M. rosa, the juvenile performs intensely pulsating movements that result in shedding of the cypris carapace ~8 h after settlement. Lepas sp. sheds the cypris cuticle ~2 days after settlement due to contractile movements of the peduncle. In Lepas anserifera, the juvenile actively breaks through the cypris carapace, which can thereafter remain for several days without impeding cirral feeding. Formation of the shell plates begins after 1-2 days under the cyprid carapace in Lepas. In M. rosa, the free juvenile retains its very thin cuticle and flexible shape for some time, and shell plates do not appear until sometime after shedding of the cypris cuticles. In Sacculina carcini, the cypris settles at the base of a seta on the host crab and remains quiescent and aligned at an angle of ~60° to the crab's cuticle. The metamorphosis involves two molts, resulting in the formation of an elongated kentrogon stage with a hollow injection stylet. Due to the orientation of the cyprid, the stylet points directly towards the base of the crab's seta. Approximately 60 h after settlement the stylet penetrates down one of the cyprid antennules and into the crab. Almost immediately afterwards the unsegmented vermigon stage, preformed in the kentrogon, passes down through the hollow stylet and into the crab's hemocoel in a process lasting only 30 s. In S. carcini, the carapace can remain around the metamorphosing individual without impeding the process.

Genetic and morphological differentiation of the Indo-West Pacific intertidal barnacle Chthamalus malayensis

Chthamalus malayensis is a common intertidal acorn barnacle widely distributed in the Indo-West Pacific. Analysis of sequences of mitochondrial cytochrome c oxidase subunit I reveals four genetically differentiated clades with almost allopatric distribution in this region. The four clades exhibit morphological differences in arthropodal characters, including the number of conical spines and number of setules of the basal guard setae on the cirri. These characters are, however, highly variable within each clade; such that the absolute range of the number of conical spines and setules overlaps between clades, and therefore, these are not diagnostic characters for taxonomic identification. The geographic distribution of the four clades displays a strong relationship between surface temperatures of the sea and ocean-current realms. The Indo-Malay (IM) clade is widespread in the tropical, equatorial region, including the Indian Ocean, Malay Peninsula, and North Borneo. The South China (SC) and Taiwan (TW) clades are found in tropical to subtropical regions, with the former distributed along the coasts of southern China, Vietnam, Thailand, and the western Philippines under the influence of the South China Warm Current. The TW clade is endemic to Taiwan, while the Christmas Island (CI) clade is confined to CI. There was weak or no population subdivision observed within these clades, suggesting high gene flow within the range of the clades. The clades demonstrate clear signatures of recent demographic expansion that predated the Last Glacial Maximum (LGM), but they have maintained a relatively stable effective population in the past 100,000 years. The persistence of intertidal fauna through the LGM may, therefore, be a common biogeographic pattern. The lack of genetic subdivision in the IM clade across the Indian and Pacific Oceans may be attributed to recent expansion of ranges and the fact that a mutation-drift equilibrium has not been reached, or the relaxed habitat requirements of C. malayensis that facilitates high concurrent gene flow. Further studies are needed to determine between these alternative hypotheses.

Arthroscopic subacromial decompression for stage-II impingement

PURPOSE

To evaluate outcomes of arthroscopic subacromial decompression for stage-II impingement.

METHODS

Records of 42 consecutive patients with stage-II impingement treated by arthroscopic subacromial decompression from January 2000 to February 2002 were reviewed. Clinical outcomes were measured using the UCLA shoulder rating scale, and radiological outcomes using anteroposterior and supraspinatus outlet shoulder radiographs.

RESULTS

The mean follow-up period was 14.6 (range, 12-30) months. Using the UCLA scale, 14 (33%) patients had an excellent result, 21 (50%) had a good result, 4 (10%) had a fair result, and 3 (7%) had a poor result. Mean component scores for the UCLA scale were: 8.0 for pain, 8.8 for function, 4.5 for forward flexion, and 4.5 for strength. The mean extent of resection was 2.9 mm in the anteroposterior and 2.0 mm in the supraspinatus outlet radiographs. There was no correlation between the extent of acromial resection and the UCLA shoulder rating scores.

CONCLUSION

Short-term results of arthroscopic subacromial decompression for stage-II impingement are favourable.

Informational factors influencing patient's childbirth preferences after prior cesarean

OBJECTIVE

A recent National Institutes of Health conference on cesarean concluded that the literature is lacking with regard to patients' childbirth preferences. The goal of this study was to examine how information patients received in pregnancy affects childbirth preferences and satisfaction.

STUDY DESIGN

In this cross-sectional study, questionnaires were issued to English- or Spanish-speaking women with prior cesarean, delivering by either vaginal birth after cesarean or repeat cesarean, at a large U.S. university hospital postpartum unit. Questions evaluated the adequacy of and satisfaction with information provided in counseling with regard to mode of delivery.

RESULTS

Eighty of 92 women approached completed the survey. The majority reported receiving no or too little information about forceps or vacuum delivery, future problems with urine or stool, fetal death, and injury.

CONCLUSION

Information that patients receive in pregnancy influences their childbirth preferences and satisfaction. Women wanted more information; particularly about urinary and fecal incontinence.

Condensing osteitis of the medial clavicle--an intermediate-term follow-up

INTRODUCTION

Condensing osteitis of the clavicle is a benign idiopathic condition affecting the medial end of the clavicle, and is characterised by sclerosis and expansion of the clavicular head.

MATERIALS AND METHODS

Nine cases of condensing osteitis were reviewed. Their mean age was 37 years (range, 22 to 65 years). All patients presented with pain and swelling localised to the sternoclavicular region. The mean length of follow-up was 38 months (range, 9 to 77 months).

RESULTS

At latest follow-up, all patients had subjective improvement in their pain symptoms, but none had any subjective decrease in the swelling around the medial clavicle. Follow-up computerised tomography (CT) scans were available for analysis in 5 patients.

CONCLUSION

The results of this study show that in the intermediate term at least, the severity of the pain appears to improve with time, although the clinical swelling over the medial clavicle does not resolve significantly. Longer follow-up will further define the long-term natural history of this rare condition.

Surgical fixation of intra-articular fractures of the distal humerus in adults

We reviewed 15 adult patients with intra-articular fractures of the distal humerus treated over a period of 2 years. All patients underwent primary open reduction and internal fixation, which included 11 double plating procedures. The fractures were classified according to the AO/ASIF system. Patient outcome was assessed subjectively by scoring the patients' residual symptom of pain and their overall satisfaction of the treatment received. Objective assessment was performed using the Mayo Elbow Performance Index (range of motion, assessment of functional status, pain and stability of the joint). At a mean follow-up of 12.3 months, 7 patients were rated as excellent; 6, as good; one, as fair; and one, as poor. These cases had an average arc of flexion of 109.7 degrees. The sub-group of type C fractures without revision surgery had a mean flexion arc of 110.7 degrees (95-140 degrees ), with 100% Good to Excellent scores. Complications included two post-operative ulnar nerve neuropraxia, one wound infection, and one fracture fibrous non-union. Three patients required revision surgery which included a total elbow arthroplasty for implant failure, whilst four patients (including the patient with the subsequent arthroplasty) required joint mobilisation procedures for residual stiffness.

Fixation of distal radius fractures using AO titanium volar distal radius plate

This study is to assess the effectiveness and outcome of the AO titanium volar distal radius plate (Synthes) in the treatment of peri-articular volar rim fractures of the distal radius. It was conducted on 22 patients with distal radius fractures who underwent open reduction, internal fixation using the AO titanium volar distal radius plate between July 1998 and December 1999 at the Changi General Hospital. The radiographs of the patients were analysed upon fracture union and assessment of wrist function was done using Gartland and Werley criteria. There were four extra-articular AO Type A2(1) and A3(3): the remaining 18 intra-articular fractures consisted of AO B3(2), AO C1(11), AO C2(2) and AO C3(3). The average follow-up period was 12.6 months (range 7-23). Radiological review showed bone healing in 21 patients (95.5%) and good articular congruity for all intra-articular fractures with less than 2 mm step-off. Three patients defaulted follow-up. Complications were few with one wound infection, one tendon rupture and three neuropraxia of the superficial radial nerve. Wrist function was excellent in three patients, good in 12 and fair in four. The AO titanium plate with its distal buttressing ability is an effective treatment modality in patients with distal radius fractures involving the peri-articular volar rim.

Conservative treatment of redisplaced Colles' fractures in elderly patients older than 60 years old - anatomical and functional outcome

A retrospective study was carried out to compare the functional outcome in two groups of patients who were 60 years old or older. One group had Colles' fractures, which had been reduced and did not redisplace. The other group's fractures redisplaced and were treated conservatively. Of the 11 patients in the first group, 82% had excellent or good functional outcome, which was not significantly different when compared with the second group of 25 patients with 68% having excellent or good functional outcome.

Telemedicine for the Medicare population: pediatric, obstetric, and clinician-indirect home interventions

BACKGROUND

This report is a supplement to an earlier evidence report, Telemedicine for the Medicare Population, which was intended to help policymakers weigh the evidence relevant to coverage of telemedicine services under Medicare. That report focused on telemedicine programs and clinical settings that had been used with or were likely to be applied to Medicare beneficiaries. While we prepared that report, it became apparent that there are also telemedicine studies among non-Medicare beneficiaries--e.g., children and pregnant women--that could inform policymakers and provide more comprehensive evidence of the state of the science regarding telemedicine applications. In addition, the first evidence report only partially included a class of telemedicine applications (called self-monitoring/testing telemedicine) in which the beneficiary used a home computer or modern-driven telephone system to either report information or access information and support from Internet resources and indirectly interact with a clinician. Self-monitoring/testing applications in the first report required direct interaction with a clinician. The goal of this report is to systematically review the evidence in the clinical areas of pediatric and obstetric telemedicine as well as home-based telemedicine where there is indirect involvement of the health care professional. (In this report, we will refer to the latter as clinician-indirect home telemedicine.) Specifically, the report summarizes scientific evidence on the diagnostic accuracy, access, clinical outcomes, satisfaction, and cost-effectiveness of services provided by telemedicine technologies for these patient groups. It also identifies gaps in the evidence and makes recommendations for evaluating telemedicine services for these populations in the future. The evidence is clustered according to three categories of telemedicine service defined in our original report: store-and-forward, self-monitoring/testing, and clinician-interactive services. The three clinical practice areas reviewed in this report are defined as follows. The term pediatric applies to any telemedicine study in which the sample consisted wholly or partially of persons aged 18 or younger, including studies with neonatal samples. The term obstetric applies to any telemedicine study in which the sample consisted entirely of women seeking pregnancy-related care. The term clinician-indirect home telemedicine applies to home-based telemedicine (called self-monitoring/testing in our original report) where a telemedicine application used in the home has only indirect involvement by the health care professional. Interactive home telemedicine was applied in this report to all patient populations.

KEY QUESTIONS

The key questions that served as a guide for reviewing the literature in the evaluation of pediatric, obstetric, and clinician-indirect home telemedicine applications were derived by consensus among the evidence-review team based on the analytic framework established for the original evidence report. For the current report, the questions were applied to studies in all three practice areas as a whole group within each of the three categories of telemedicine services: store-and-forward; self-monitoring/testing; and clinician-interactive. The specific key questions were: 1. Does telemedicine result in comparable diagnosis and appropriateness of recommendations for management? 2. Does the availability of telemedicine provide comparable access to care? 3. Does telemedicine result in comparable health outcomes? 4. Does telemedicine result in comparable patient or clinician satisfaction with care? 5. Does telemedicine result in comparable costs of care and/or cost-effectiveness?

METHODS

We searched for peer-reviewed literature using several bibliographic databases. In addition, we conducted hand searches of leading telemedicine journals and identified key papers from the reference lists of journal articles. For our original evidence report on telemedicine for the Medicare population, we designed a search to find any publications about telemedicine and used it to search the MEDLINE, CINAHL, and HealthSTAR databases for all years the databases were available. Through this process, we captured studies of pediatric, obstetric, and clinician-indirect home telemedicine; however, they were excluded from the original report since they were outside its scope. For this supplemental report, we reviewed our original search results and identified studies relevant to this report. We identified additional studies from the reference lists of included papers and from hand searching two peer-reviewed telemedicine publications, the Journal of Telemedicine and Telecare and Telemedicine Journal. We critically appraised the included studies for each study area and key question and discussed the strengths and limitations of the most important studies at weekly meetings of the research team. We also developed recommendations for research to address telemedicine knowledge gaps. To match these gaps with the capabilities of specific research methods, we classified the telemedicine services according to the type of evidence that would be needed to determine whether the specific goals of covering such services had been met. We emphasized the relationship between the type and level of evidence found in the systematic review of effectiveness and the types of studies that might be funded to address the gaps in knowledge in this growing field of research.

FINDINGS

We identified a total of 28 eligible studies. In the new clinical areas, we found few studies in store-and-forward telemedicine. There is some evidence of comparable diagnosis and management decisions made using store-and-forward telemedicine from the areas of pediatric dental screening, pediatric ophthalmology, and neonatalogy. In self-monitoring/testing telemedicine for the areas of pediatrics, obstetrics, and clinician-indirect home telemedicine, there is evidence that access to care can be improved when patients and families have the opportunity to receive telehealth care at home rather than in-person care in a clinic or hospital. Access is particularly enhanced when the telehealth system enables timely communication between patients or families and care providers that allows self-management and necessary adjustments that may prevent hospitalization. There is some evidence that this form of telemedicine improves health outcomes, but the study sample sizes are usually small, and even when they are not, the treatment effects are small. There is also some evidence for the efficacy of clinician-interactive telemedicine, but the studies do not clearly define which technologies provide benefit or cost-efficiency. Some promising areas for diagnosis include emergency medicine, psychiatry, and cardiology. Most of the studies measuring access to care provide evidence that it is improved. Although none of these studies were randomized controlled trials, they provide some evidence of access improvement over prior conditions. Clinician-interactive telemedicine was the only area for which any cost studies were found. The three cost studies did not adequately demonstrate that telemedicine reduces costs of care (except comparing only selected costs). No study addressed cost-effectiveness.

CONCLUSIONS

This supplemental report covering the areas of pediatrics, obstetrics, and indirect-clinician home telemedicine echoes the findings of our initial report for the Medicare domain, which is that while the use of telemedicine is small but growing, the evidence for its efficacy is incomplete. Many of the studies are small and/or methodologically limited, so it cannot be determined whether telemedicine is efficacious. Future studies should focus on the use of telemedicine in conditions where burden of illness and/or barriers to access for care are significant. Use of recent innovations in the design of randomized controlled trials for emerging technologies would lead to higher quality studies. Journals publishing telemedicine evaluation studies must set high standards for methodologic quality so that evidence reports need not rely on studies with marginal methodologies.

Hormone replacement therapy and cognition: systematic review and meta-analysis

CONTEXT

Some observational data suggest that hormone replacement therapy (HRT) may reduce the risk of cognitive decline and dementia but results have been conflicting.

OBJECTIVE

To review and evaluate studies of HRT for preventing cognitive decline and dementia in healthy postmenopausal women.

DATA SOURCES

Studies with English-language abstracts identified in MEDLINE (1966-August 2000), HealthSTAR (1975-August 2000, PsychINFO (1984-August 2000); Cochrane Library databases; and articles listed in reference lists of key articles.

STUDY SELECTION

Randomized controlled trials and cohort studies were reviewed for the effects of HRT on cognitive decline; cohort and case-control studies were reviewed for dementia risk. No randomized controlled trials regarding dementia risk were identified.

DATA EXTRACTION

Twenty-nine studies met inclusion criteria and were rated. Two reviewers rated study quality independently and 100% agreement was reached on Jadad scores and 80% agreement was reached on US Preventive Services Task Force quality scores. A final score was reached through consensus if reviewers disagreed.

DATA SYNTHESIS

Studies of cognition were not combined quantitatively because of heterogeneous study design. Women symptomatic from menopause had improvements in verbal memory, vigilance, reasoning, and motor speed, but no enhancement of other cognitive functions. Generally, no benefits were observed in asymptomatic women. A meta-analysis of observational studies suggested that HRT was associated with a decreased risk of dementia (summary odds ratio, 0.66; 95% confidence interval, 0.53-0.82). However, possible biases and lack of control for potential confounders limit interpretation of these studies. Studies did not contain enough information to assess adequately the effects of progestin use, various estrogen preparations or doses, or duration of therapy.

CONCLUSIONS

In women with menopausal symptoms, HRT may have specific cognitive effects, and future studies should target these effects. The meta-analysis found a decreased risk of dementia in HRT users but most studies had important methodological limitations.

Metacarpal and proximal phalangeal fractures--fixation with multiple intramedullary Kirschner wires

The use of intramedullary wires for fixation of fractures of the metacarpal and proximal phalanx in our hospital was reviewed. Twenty-six patients with 26 metacarpal fractures and four proximal phalangeal fractures were treated using this technique from 1993 to 1998. After a minimal follow-up of nine months, all the patients were assessed clinically and radiologically. All fractures proceeded to bony union at an average of 5.7 weeks (range four to eight weeks). With this simple and minimally invasive technique, most of these patients required very short hospital stay and were able to start mobilisation relatively early. The general outcome was good hand function with few complications.

Put prevention into practice: a controlled evaluation

OBJECTIVES

The purpose of this study was to evaluate whether Put Prevention Into Practice (PPIP) materials affected the delivery of 8 clinical preventive services.

METHODS

Program materials were provided to a family medicine practice serving a diverse, low-income population. Appropriate use of clinical preventive services was assessed via medical record reviews at baseline, 6 months, 18 months, and 30 months at both intervention and control sites.

RESULTS

The delivery rates of 7 clinical preventive services were higher in the intervention site at 6 months. These rates had flattened or decreased by 30 months.

CONCLUSIONS

Use of PPIP materials modestly improved delivery of certain clinical preventive services. Sustained improvement will require substantial system changes and ongoing support.

A comparison of stereoscopic fluorescein angiography with indocyanine green videoangiography in age-related macular degeneration

PURPOSE

To correlate features of indocyanine green (ICG) videoangiography with stereo film fluorescein angiography (FA) in the analysis of age-related macular degeneration (AMD).

DESIGN

A retrospective study with concurrent comparison of two methods of assessment on one set of patients with AMD undergoing sequential FA-ICG videoangiography.

METHODS

One hundred four patients with AMD who had undergone immediately sequential FA-ICG videoangiography were selected in a consecutive fashion from the photographic files of the Casey Eye Institute. Three interpreters independently graded in an unbiased fashion the FA features of AMD. These were compared with ICG videoangiography features of hypocyanescence (ICG videoangiography hypofluorescence), moderate or intense hypercyanescence (ICG videoangiography hyperfluorescence), or absence of fluorescence over background (ICG videoangiography isocyanescence). We also assessed ICG videoangiography features in the opposite eye of those with choroidal neovascularization (CNV) by FA in one eye by examining an additional 96 FA-ICG videoangiography scans.

MAIN OUTCOME MEASURES

Outcomes were the ICG videoangiography characteristics of classic and occult CNV, serous pigment epithelial detachments (SPEDs) both with and without CNV, macular hemorrhage, and the comparative size of these features.

RESULTS

There were 25 eyes that had significant macular hemorrhage by FA. Of these, the FA revealed CNV in its entirety under or near the hemorrhage in 11. The ICG examination revealed all 11 plus an additional 12 hypercyanescent features that were not visible by FA. Although 26 of 32 SPEDs had CNV by FA analysis, 31 of 32 had well-defined hypercyanescence under or at the SPED edge by ICG videoangiography. Eighty-seven percent of eyes with classic choroidal neovascular membranes (CCNV; 20 of 23) and 93% of eyes with fibrovascular pigment epithelial detachments (FVPED; 66 of 71) were hypercyanescent with distinct edges. Fifty percent of eyes with only late leakage of undetermined source (LLUS) were hypercyanescent, whereas 50% were isocyanescent on ICG videoangiography. There were four of 104 eyes in which ICG videoangiography revealed poorly defined hypercyanescent areas when, by FA, there were only drusen or elevated blocked fluorescence. Indocyanine green videoangiography revealed only three eyes with poorly defined hypercyanescence of 200 fellow eyes in patients with unilateral AMD.

CONCLUSIONS

Indocyanine green videoangiography correlated fairly well with stereoscopic FA for the presence of CCNV or FVPED, but correlated poorly when LLUS was present. In certain cases where CNV was associated with SPED or macular hemorrhage, ICG videoangiography demonstrated features not apparent on FA.

Bilateral avascular necrosis of the humeral trochleae after chemotherapy

We describe a patient who developed avascular necrosis of both humeral trochleae after combination chemotherapy for acute lymphoblastic leukaemia. This presented as progressive stiffness of both elbows with little pain. Radiography and MRI confirmed the presence of avascular necrosis at both sites. This region corresponds to a watershed between the medial and lateral vascular arcades which supply the distal humerus and may explain the susceptibility of this bony region to avascular necrosis. Treatment involved capsulectomy of the elbow and removal of osteophytes giving a good functional outcome on both sides.

Sociodemographic factors and the assignment of do-not-resuscitate orders in patients with acute myocardial infarctions

OBJECTIVES

This study examined the impact of sociodemographic and clinical factors, measured at the individual or ecological (zip code) level, on the assignment of do-not-resuscitate (DNR) orders.

DESIGN

This was a retrospective study (analysis of secondary data).

SUBJECTS

We used a probability sample of 974 patients admitted to 30 medium to large California hospitals with acute myocardial infarctions in 1990 to 1991; the sample was originally designed to validate risk adjustment with administrative data.

METHODS

Multivariate logistic regression was used to adjust DNR assignment for age, gender, race, probability of death, functional impairments, payment source, hospital teaching status, and ecological measures of educational attainment, home ownership, and income.

RESULTS

DNR assignment was inversely associated with black race and positively associated with age, probability of death, cognitive impairment, and poor nutritional status. When the probability of death was very low, DNR orders were assigned less frequently to men than to women (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2 to 0.7 at probability of death = 0.10). However, men were significantly more likely to receive a DNR order than women when the probability of death was very high (OR, 4.4; 95% CI, 1.2 to 16.3 at probability of death = 0.90).

CONCLUSIONS

Older, white, sicker, or functionally impaired patients receive DNR orders more often than younger, black, healthier, or functionally intact patients do. Adjusting for these factors, DNR assignment is associated with gender through an interaction involving the probability of death. Future studies should reexamine the impact of these factors on DNR assignment and explore the role of patient values and patient-physician communication barriers.

Colonic neoplasia in patients with nonspecific GI symptoms

BACKGROUND

The purpose of this study was to determine the prevalence rate of colonic polyps or masses 1 cm or greater in diameter in patients with nonspecific abdominal symptoms, from diverse practice settings, using a national endoscopic database.

METHODS

Consecutive patients undergoing colonoscopy were included based on procedure indication. Endoscopic data were generated with a computer database at each practice site, transmitted to a central data bank and merged with data from multiple sites for analysis. Group 1 patients had nonspecific abdominal symptoms, which were defined as pain, constipation and diarrhea. Group 2 patients had a positive fecal occult blood test. Group 3 patients were asymptomatic, undergoing screening colonoscopy. Serious colon pathology was defined as a polyp or mass greater than 9 mm in size.

RESULTS

Data were collected from 31 practice sites in 21 states during a period of 18 months. Of the 20,745 colonoscopy examinations, 9.2% were performed to evaluate patients with nonspecific abdominal symptoms, excluding other indications. Among patients with nonspecific symptoms 7.27% had polyp(s) 1 cm or greater in diameter compared with 17.05% of patients with positive fecal occult blood test (odds ratio 2.12: CI [1.73, 2.60]; p < 0.001). Patients with nonspecific symptoms had similar rates of large polyps as asymptomatic patients (7.27% vs. 6.45%, p = 0.32). Multivariate analysis identified several independent variables including increasing age, male gender and practice site at a Veterans Affairs Medical Center.

CONCLUSIONS

In diverse, practice-based settings, patients with nonspecific abdominal symptoms who are referred for colonoscopy do not have a higher risk of serious colonic pathology than asymptomatic patients.