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1.
Phys Rev Lett ; 104(14): 142301, 2010 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-20481933

RESUMO

This Letter presents the first measurement of event-by-event fluctuations of the elliptic flow parameter v(2) in Au+Au collisions at square root(s(NN))=200 GeV as a function of collision centrality. The relative nonstatistical fluctuations of the v(2) parameter are found to be approximately 40%. The results, including contributions from event-by-event elliptic flow fluctuations and from azimuthal correlations that are unrelated to the reaction plane (nonflow correlations), establish an upper limit on the magnitude of underlying elliptic flow fluctuations. This limit is consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. These results provide important constraints on models of the initial state and hydrodynamic evolution of relativistic heavy ion collisions.

2.
Phys Rev Lett ; 104(6): 062301, 2010 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-20366815

RESUMO

A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary collisions is observed at all Delta eta. As in p+p collisions, the near side is characterized by a peak of correlated partners at small angle relative to the trigger particle. However, in central Au+Au collisions an additional correlation extended in Delta eta and known as the "ridge" is found to reach at least |Delta eta| approximately = 4. The ridge yield is largely independent of Delta eta over the measured range, and it decreases towards more peripheral collisions. For the chosen (p(T)(trig) cut, the ridge yield is consistent with zero for events with less than roughly 100 participating nucleons.

3.
Org Lett ; 3(7): 1081-4, 2001 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-11277800

RESUMO

[structure: see text]. A new strategy for the synthesis of substituted azulenes is reported, based on the reaction of beta'-bromo-alpha-diazo ketones with rhodium carboxylates. The key transformation involves intramolecular addition of a rhodium carbenoid to an arene pi-bond, electrocyclic ring opening, beta-elimination, tautomerization, and trapping to produce 1-hydroxyazulene derivatives. The synthetic utility of the method is enhanced by the ability of the triflate derivatives to participate in Suzuki coupling reactions, as illustrated in a synthesis of the antiulcer drug egualen sodium (KT1-32).


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Antiulcerosos/síntese química , Cicloeptanos/síntese química , Ródio/química , Sesquiterpenos/síntese química , Azulenos , Benzeno/química , Humanos , Cetonas/química , Estrutura Molecular
4.
Obstet Gynecol ; 56(1): 119-21, 1980 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6446052

RESUMO

A prospective randomly controlled study was conducted on 200 women undergoing sterilization by application of clips to the fallopian tubes. Laparotomy or laparoscopy was used, and the patients' response to the procedure was evaluated. There were few surgical complications. Postoperative pain and discomfort were experienced for a mean of 2.7 and 2.4 days in the those undergoing minilaparotomy and laparoscopy, respectively. The patients' response indicates a marginal benefit from the laparoscopic approach to application of clips to the fallopian tubes.


Assuntos
Laparoscopia , Laparotomia , Esterilização Tubária/métodos , Feminino , Febre , Humanos , Dor Pós-Operatória , Complicações Pós-Operatórias , Gravidez , Succinilcolina/efeitos adversos , Fatores de Tempo
5.
Fertil Steril ; 42(6): 843-8, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6500077

RESUMO

This study investigates the prevalence of Chlamydia trachomatis antibodies in 164 infertile women who underwent diagnostic laparoscopy and dye insufflation as part of routine infertility investigations. C. trachomatis antibodies were found in 36 (22%) of 164 infertile women, which was significantly more than the prevalence of antibodies in a control group (22 of 200, 11%). C. trachomatis antibodies were found in 25 (35.7%) of 70 infertile women who had laparoscopically verified peripheral tubal disease. This was significantly more than the prevalence of C. trachomatis antibodies in infertile women with normal fallopian tubes (6 of 52, 11.5%). The prevalence of C. trachomatis antibodies in infertile patients with laparoscopically verified cornual disease was similar to those without cornual disease. C. trachomatis was not isolated from any of the patients studied. This study confirms that past chlamydial salpingitis is associated with the development of peripheral fallopian tube obstruction with resultant infertility.


Assuntos
Infecções por Chlamydia/complicações , Doenças das Tubas Uterinas/complicações , Infertilidade Feminina/etiologia , Adulto , Anticorpos Antibacterianos/análise , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Doenças das Tubas Uterinas/etiologia , Feminino , Humanos , Gravidez , Salpingite/complicações , Salpingite/etiologia
6.
Phys Rev Lett ; 102(14): 142301, 2009 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-19392428

RESUMO

We present the first measurements of the pseudorapidity distribution of primary charged particles in Cu+Cu collisions as a function of collision centrality and energy, sqrt[s_{NN}]=22.4, 62.4, and 200 GeV, over a wide range of pseudorapidity, using the PHOBOS detector. A comparison of Cu+Cu and Au+Au results shows that the total number of produced charged particles and the rough shape (height and width) of the pseudorapidity distributions are determined by the number of nucleon participants. More detailed studies reveal that a more precise matching of the shape of the Cu+Cu and Au+Au pseudorapidity distributions over the full range of pseudorapidity occurs for the same N{part}/2A rather than the same N_{part}. In other words, it is the collision geometry rather than just the number of nucleon participants that drives the detailed shape of the pseudorapidity distribution and its centrality dependence at RHIC energies.

7.
Phys Rev Lett ; 98(24): 242302, 2007 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-17677957

RESUMO

This Letter presents measurements of the elliptic flow of charged particles as a function of pseudorapidity and centrality from Cu-Cu collisions at 62.4 and 200 GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider. The elliptic flow in Cu-Cu collisions is found to be significant even for the most central events. For comparison with the Au-Au results, it is found that the detailed way in which the collision geometry (eccentricity) is estimated is of critical importance when scaling out system-size effects. A new form of eccentricity, called the participant eccentricity, is introduced which yields a scaled elliptic flow in the Cu-Cu system that has the same relative magnitude and qualitative features as that in the Au-Au system.

8.
Phys Rev Lett ; 97(1): 012301, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16907368

RESUMO

We report on measurements of directed flow as a function of pseudorapidity in Au + Au collisions at energies of square root of SNN = 19.6, 62.4, 130 and 200 GeV as measured by the PHOBOS detector at the BNL Relativistic Heavy Ion Collider. These results are particularly valuable because of the extensive, continuous pseudorapidity coverage of the PHOBOS detector. There is no significant indication of structure near midrapidity and the data surprisingly exhibit extended longitudinal scaling similar to that seen for elliptic flow and charged particle pseudorapidity density.

9.
Phys Rev Lett ; 96(21): 212301, 2006 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-16803231

RESUMO

We present transverse momentum distributions of charged hadrons produced in Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. The spectra are measured for transverse momenta of 0.25 < pT < 5.0 GeV/c at square root of SNN = 62.4 GeV and 0.25 < pT < 7.0 GeV/c at square root of SNN = 200 GeV, in a pseudorapidity range of 0.2 < eta < 1.4. The nuclear modification factor R(AA) is calculated relative to p + p data at both collision energies as a function of collision centrality. At a given collision energy and fractional cross section, R(AA) is observed to be systematically larger in Cu + Cu collisions compared to Au + Au. However, for the same number of participating nucleons, R(AA) is essentially the same in both systems over the measured range of pT, in spite of the significantly different geometries of the Cu + Cu and Au + Au systems.

11.
Phys Rev Lett ; 94(12): 122303, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15903910

RESUMO

This Letter describes the measurement of the energy dependence of elliptic flow for charged particles in Au+Au collisions using the PHOBOS detector at the Relativistic Heavy Ion Collider. Data taken at collision energies of square root of s(NN)=19.6, 62.4, 130, and 200 GeV are shown over a wide range in pseudorapidity. These results, when plotted as a function of eta(')=|eta|-y(beam), scale with approximate linearity throughout eta('), implying no sharp changes in the dynamics of particle production as a function of pseudorapidity or increasing beam energy.

12.
Genitourin Med ; 61(5): 311-8, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2931347

RESUMO

The inoculation of feline keratoconjunctivitis agent (Chlamydia psittaci) directly into the oviducts of eight cats produced an acute disease that was characterised by hyperaemia of the tissue and pronounced polymorphonuclear leucocyte infiltration of the epithelium and subepithelial stroma. The lumens of the tubes contained exudates of desquamated epithelial cells and polymorphonuclear leucocytes. After about 30 days the disease subsided leaving chronic inflammation with the tissue infiltrated with both polymorphonuclear and mononuclear cells. Fimbrial scarring and formation of adhesions were apparent by 40 to 50 days after inoculation. Chlamydiae were isolated in McCoy cell cultures from most cats, in one for as long as 51 days after inoculation. Inclusions were seen in histological sections or smears of cells from the fimbriae of four of the eight cats. Six of the eight cats developed antibodies to feline keratoconjunctivitis agent, which were detectable as early as 12 days after inoculation. To facilitate repeated examinations of the cats' fallopian tubes, techniques for laparoscopy in cats and for the collection of specimens while under laparoscopic examination were developed. The latter technique has since been applied successfully in man.


Assuntos
Infecções por Chlamydia/microbiologia , Modelos Animais de Doenças , Doença Inflamatória Pélvica/microbiologia , Animais , Gatos , Infecções por Chlamydia/patologia , Chlamydophila psittaci , Tubas Uterinas/microbiologia , Tubas Uterinas/patologia , Feminino , Laparoscopia/métodos , Doença Inflamatória Pélvica/patologia
13.
J Clin Microbiol ; 6(2): 132-5, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-197116

RESUMO

Plasma samples from 245 regular plasma donors for Plasma Alliance, Inc. (Knoxville, Tenn.) were tested for the presence of antibody to hepatitis A antigen. Antibody was detected at an immune adherence hemagglutination titer of 1:10 or greater in 37% (91 of 245) of the donors. A statistically significant difference in the frequency of anti-hepatitis A was found between the 18- to 29-year-old group (30%) and the 30- to 49-year-old group (57%). No significant differences between whites and blacks or males afemales were observed. Eighty percent of the donors were in the age range of 18 to 29 years, whereas 48% of the higher-titered plasmas (1:1,000 or greater) were in the 30 to 49 age group. By preselection of donors, it would be possible to produce an immune serum globulin with a specific anti-hepatitis A titer.


Assuntos
Anticorpos Antivirais/análise , Doadores de Sangue , Hepatovirus/imunologia , Adolescente , Adulto , Fatores Etários , Antígenos da Hepatite B , Humanos , Pessoa de Meia-Idade , Grupos Raciais , Fatores Sexuais
14.
FASEB J ; 9(5): 434-40, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7896016

RESUMO

To obtain a database of accurate anatomical images onto which dosimetry data of electromagnetic fields could be mapped, a healthy Sprague-Dawley rat, rhesus monkey, and pigmy goat were scanned using magnetic resonance imaging (MRI). Axial sections throughout the length of the animals were collected. Sections were 3 mm thick for the rat and 5 mm thick for the monkey and goat. Sagittal sections (2 mm thick) of the rat head were also scanned. Images were recorded on magnetic tape and transferred to computer disk for image enhancement and network distribution. Images are available in 16 bit Big Endian signed or 8 bit TIFF formats. This is the first database of contiguous MRI axial scans of rat, monkey, and goat available for distribution via magnetic tape (4 mm DDS) or Internet file transfer protocol. Digital transfer of the data was selected to preserve the integrity of each image, circumventing the need for the user to scan the images back into a digital format for use with their software. These images should be useful to physiologists, neuroscientists, veterinarians, anatomists, and teachers. Reconstructing these 2-dimensional images into 3-dimensional structures is an effective media for conveying spatial anatomical information in a quick and comprehensive manner.


Assuntos
Bases de Dados Factuais , Imageamento por Ressonância Magnética , Animais , Cabras , Macaca mulatta , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie
15.
Phys Rev Lett ; 93(8): 082301, 2004 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-15447175

RESUMO

The measured pseudorapidity distribution of primary charged particles in minimum-bias d+Au collisions at sqrt[s(NN)]=200 GeV is presented for the first time. This distribution falls off less rapidly in the gold direction as compared to the deuteron direction. The average value of the charged particle pseudorapidity density at midrapidity is |eta|< or =0.6)=9.4+/-0.7(syst) and the integrated primary charged particle multiplicity in the measured region is 82+/-6(syst). Estimates of the total charged particle production, based on extrapolations outside the measured pseudorapidity region, are also presented. The pseudorapidity distribution, normalized to the number of participants in d+Au collisions, is compared to those of Au+Au and p+(-)p systems at the same energy. The d+Au distribution is also compared to the predictions of the parton saturation model, as well as microscopic models.

17.
Phys Rev Lett ; 87(10): 102303, 2001 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11531476

RESUMO

The charged-particle pseudorapidity density dN(ch)/d eta has been measured for Au+Au collisions at sqrt[s(NN)] = 130 GeV at RHIC, using the PHOBOS apparatus. The total number of charged particles produced for the 3% most-central Au+Au collisions for /eta/

18.
Phys Rev Lett ; 91(5): 052303, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12906591

RESUMO

We present measurements of the pseudorapidity distribution of primary charged particles produced in Au+Au collisions at three energies, sqrt[s(NN)]=19.6, 130, and 200 GeV, for a range of collision centrali-ties. The distribution narrows for more central collisions and excess particles are produced at high pseudorapidity in peripheral collisions. For a given centrality, however, the distributions are found to scale with energy according to the "limiting fragmentation" hypothesis. The universal fragmentation region described by this scaling grows in pseudorapidity with increasing collision energy, extending well away from the beam rapidity and covering more than half of the pseudorapidity range over which particles are produced. This approach to a universal limiting curve appears to be a dominant feature of the pseudorapidity distribution and therefore of the total particle production in these collisions.

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