Observation of Strong Nuclear Suppression in Exclusive J/ψ Photoproduction in Au+Au Ultraperipheral Collisions at RHIC.

We report a measurement of exclusive J/ψ and ψ(2s) photoproduction in Au+Au ultraperipheral collisions at sqrt[s_{NN}]=200 GeV using the STAR detector. For the first time, (i) the ψ(2s) photoproduction in midrapidity at the Relativistic Heavy-Ion Collider has been experimentally measured; (ii) nuclear suppression factors are measured for both the coherent and incoherent J/ψ production. At average photon-nucleon center-of-mass energy of 25.0 GeV, the coherent and incoherent J/ψ cross sections of Au nuclei are found to be 71±10% and 36±7%, respectively, of that of free protons. The stronger suppression observed in the incoherent production provides a new experimental handle to study the initial-state parton density in heavy nuclei. Data are compared with theoretical models quantitatively.

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.

Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central

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}

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}

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.

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.

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.

Controllable formation of nanoscale patterns on TiO2 by conductive-AFM nanolithography.

We report on the nanopatterning of double-bond-terminated silane (5-hexenyltrichlorosilane, HTCS) molecules on titania (TiO2) using conductive atomic force microscopy (AFM). The influences of tip electrostatic potential and scanning velocity, relative humidity and of the repeated application of voltage on the topographic height, width, and hydrophilic and hydrophobic contrast of the resultant patterns were investigated. Tip voltage and tip velocity ( v) were applied between -10 V

Isolated intraspinal germinoma in a child with congenital adrenal hyperplasia.

STUDY DESIGN: Case report. OBJECTIVE: To report an intramedullary germinoma associated with congenital adrenal hyperplasia (CAH). METHOD: We report a 14-year-old white male with CAH who was found to have an intramedullary germinoma of the conus medullaris. Presentation and evaluation were for progressive urinary incontinence. A brief review of relevant literature was presented. RESULTS: Cases where germinomas have occurred simultaneously with CAH have been identified intracranially, but to our knowledge, this is the first case of CAH and intramedullary spinal cord germinoma occurring simultaneously. CONCLUSION: Although rare, primary intramedullary germinomas do occur. The association between CAH and spinal cord germinoma should be considered by clinicians.

Case report: liver glycogen synthase deficiency--a cause of ketotic hypoglycemia.

Glycogen synthase deficiency is a rare inborn error of metabolism, characterized by fasting hypoglycemia, hypoglycemic seizures, and ketonuria. Only 7 families with 14 affected children have been reported. Here, we report an additional patient with this deficiency. Findings in this patient were clinically and biochemically consistent with those reported in patients with ketotic hypoglycemia and may alert the clinician to consider glycogen synthase deficiency.

Roadmap to physical medicine and rehabilitation: answers to medical students' questions about the field.

Medical specialty training has undergone dramatic changes in the last 5 yr. This article was prepared by the Undergraduate Education Committee of the Association of Academic Physiatrists in an attempt to help guide medical students who are considering a career in physical medicine and rehabilitation. This report is an update of two previous articles addressing medical students' questions to assist them in making educated decisions about residency training and medical practice.

Manipulation efficacy: Upper body.

Manipulation, or manual medicine, is a highly utilized form of treatment for many types of musculoskeletal disorders, but there are many questions about the efficacy and safety of this form of treatment. This review of published trials for treatment of the upper body (cervical, thoracic, and upper limb) describes the patient groups that have been studied and may benefit from manual treatment, their outcomes, and their limitations. Cervical manipulation in particular has historically received criticism regarding safety, and the incidence of side effects, severe complications, and contraindications are discussed. The number of studies published for the upper body is small compared to the lumbar spine, and the lack of uniformity of the information still leaves the individual practitioner to decide if and when manipulation fits into his or her treatment algorithms for this region of the body.

The use of controlled subatmospheric pressure to promote wound healing in preparation for split-thickness skin grafting in a fourth degree burn.

Subatmospheric pressure application to acute and chronic wounds has been shown to increase local wound blood flow, increase the rate of formation of granulation tissue, and enhance bacterial clearance. The mechanical forces applied to the wound enhance the rate of granulation tissue formation by the increase intracellular messengers regulating protein production and turnover. This method of wound care is particularly useful for larger wounds that could not be readily closed by local methods, but may also be useful for chronic wounds in debilitated patients who may not be ideal surgical candidates. Further basic scientific research is needed to discern the exact mechanisms of action of subatmospheric pressure, and more clinical experience is needed to establish guidelines for its application. Further clinical studies with larger subject populations in a randomized prospective study would lend support to the utility of this wound management protocol.

Childhood hypoglycemia in an urban emergency department: epidemiology and a diagnostic approach to the problem.

OBJECTIVE: To 1) determine the prevalence of hypoglycemia in childhood in a pediatric emergency department (ED), 2) determine epidemiology of idiopathic ketotic hypoglycemia (IKH), 3) determine diagnostic yield of the workup of hypoglycemia, and 4) review a diagnostic approach to hypoglycemia. SETTING: Urban pediatric ED of a tertiary level children's hospital. METHODS: Retrospective review of all medical records with a primary or secondary diagnosis of hypoglycemia (ICD-9 code 251.2) seen at the ED between 1/92 and 8/95. RESULTS: Thirty-one patients were identified. Mean blood glucose was 34.2 mg/dl. Prevalence of hypoglycemia among population seeking care in our ED was 6.54/100,000 visits. Eighteen patients were diagnosed with IKH for a prevalence of 3.9/100,000. IKH demographics were: mean age 27.7 months; 12 males, 6 females; 8 white, 9 black, and 1 not available. The weights of five patients were < 25th percentile. Fourteen of the 18 IKH patients had hormone studies done insulin [cost $40], growth hormone [$69], cortisol [$54]. All 14 had appropriately suppressed insulin levels (< 5microU/ml) and high cortisol levels > 22 microg/ml. Thirteen of the 14 had normal or high growth hormone (GH) levels (0.7-6 ng/ml). Four IKH patients had urine drug screens ($280); all were negative. Although no IKH patient was febrile, six had sepsis workups ($380); all were negative. Urine ketones were positive in 15 of the 18 tested (> 3+ in eight patients). Mean anion gap was 20 (range: 16-30). Eight of the 18 IKH patients were discharged from the ED after return to normal status. CONCLUSIONS: IKH is the most common cause of hypoglycemia in children beyond the infancy period. In its typical presentation (previously healthy one- to five-year-old, with normal growth and development, who presents with a first episode of symptomatic fasting hypoglycemia and appropriate degree of ketonuria, without hepatomegaly, and with resolution of symptoms on administration of glucose), an extensive and overzealous workup for endocrinopathy or inborn error of metabolism is not necessary.

Insulin management and metabolic control of type 1 diabetes mellitus in childhood and adolescence in 18 countries. Hvidøre Study Group on Childhood Diabetes.

Insulin regimens and metabolic control in children and adolescents with Type 1 diabetes mellitus were evaluated in a cross-sectional, non-population-based investigation, involving 22 paediatric departments, from 18 countries in Europe, Japan, and North America. Blood samples and information were collected from 2873 children from March to August 1995. HbA1c was determined once and analysed centrally (normal range 4.4-6.3%, mean 5.4%). Year of birth, sex, duration of diabetes, height, body weight, number of daily insulin injections, types and doses of insulin were recorded. Average HbA1c in children under 11 years was 8.3 +/- 1.3% (mean +/- SD) compared with 8.9 +/- 1.8% in those aged 12-18 years. The average insulin dose per kg body weight was almost constant (0.65 U kg(-1) 24 h(-1)) in children aged 2-9 years for both sexes, but there was a sharp increase during the pubertal years, particularly in girls. The increase in BMI of children with diabetes was much faster during adolescence compared to healthy children, especially in females. Sixty per cent of the children (n = 1707) used two daily insulin injections while 37% (n = 1071) used three or more. Of those on two or three injections daily, 37% used pre-mixed insulins, either alone or in combination with short- and intermediate-acting insulin. Pre-adolescent children on pre-mixed insulin showed similar HbA1c levels to those on a combination of short- and long-acting insulins, whereas in adolescents significantly better HbA1c values were achieved with individual combinations. Very young children were treated with a higher proportion of long-acting insulin. Among adolescent boys, lower HbA1c was related to use of more short-acting insulin. This association was not found in girls. We conclude that numerous insulin injection regimens are currently used in paediatric diabetes centres around the world, with an increasing tendency towards intensive diabetes management, particularly in older adolescents. Nevertheless, the goal of near normoglycaemia is achieved in only a few.

Perceived job satisfaction factors of nursing assistants employed in Midwest nursing homes.

The purpose of this study was to determine the perceptions of nursing assistants employed in Midwest nursing homes in relation to job satisfaction. The study population included 283 nursing assistants employed in 24 nursing homes. An analysis of frequencies using chi square at the .05 level of significance was used to examine the significance of the responses. Study results indicated the nursing assistants were most concerned with the security of their jobs, the potential within their jobs for growth and development, socialization, and challenge in their work.

Adolescents' health attitudes and adherence to treatment for insulin-dependent diabetes mellitus.

Adolescents' health attitudes and adherence to treatment for insulin-dependent diabetes mellitus (IDDM) were evaluated using the protection motivation theory (PMT). We expected cognitive appraisals of adherence (self-efficacy for treatment management, response efficacy of treatment, response costs of adherence) to be more influential for adherence than appraisals of nonadherence (rewards of nonadherence, perceptions of the risks of nonadherence, perceived severity of the risks). Adolescents (N = 101) with IDDM completed self-report measures of treatment adherence and of the PMT variables. Hierarchical regression analyses revealed that cognitions concerning adherence explained a statistically significant proportion of the variance in treatment adherence (sr2 = .17). Response costs of adherence produced the strongest correlations with overall adherence and with three of the four individual components of IDDM treatment (insulin injections, blood glucose monitoring, diet). The findings suggest that persuasive health communications might focus on appraisals of adherence rather than on risks of nonadherence.

Manipulation for the treatment of occupational low back pain.

Manual medicine techniques are performed to correct abnormal structural findings of tenderness, asymmetry, restricted range of motion, and tissue texture changes. Nonthrusting methods include articulatory, muscle energy, functional, counter-strain, and soft tissue manipulations.

Hiccups associated with lateral medullary syndrome. A case report.

We present a case of persistent hiccups (singultus) after a lateral medullary cerebrovascular accident. The patient presented with a two-day history of nausea and vomiting. Clinically, the patient had a loss of pain and temperature on the left side of the face, a loss of pain and temperature on the right side of the trunk, a mild left hemiparesis, and a left-sided ataxia. Nystagmus, diplopia, and hiccups were also evident. A left lateral medullary syndrome in the vascular distribution of the posterior inferior cerebellar artery was diagnosed. Work-up included a magnetic resonance imaging angiogram, which revealed an occlusion v high-grade stenosis of the basilar artery. The patient reported that the most distressing symptom was the chronic hiccups (25/min), which interfered with nutrition, sleep, and activity. While in the acute care hospital, the patient was treated with prochlorperazine, promethazine, and chlorpromazine. Each of these medications was unsuccessful in stopping the hiccups. After a search of the European literature revealed that baclofen was recommended as the drug of choice for stopping persistent hiccups, the patient was given 5 mg of baclofen by mouth three times per day, and the hiccups abated within 48 hours. The baclofen was discontinued after one week of therapy, and the hiccups did not return. We recommend consideration of baclofen for the treatment of persistent hiccups after lateral medullary syndrome because of its desirable side effects and reported success rate compared with other drugs used to treat chronic hiccups.