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Slifer K, Amarian M, Auerbach L, Averett T, Berthot J, Bertin P, Bertozzi B, Black T, Brash E, Brown D, Burtin E, Calarco J, Cates G, Chai Z, Chen JP, Choi S, Chudakov E, Ciofi Degli Atti C, Cisbani E, de Jager CW, Deur A, DiSalvo R, Dieterich S, Djawotho P, Finn M, Fissum K, Fonvieille H, Frullani S, Gao H, Gao J, Garibaldi F, Gasparian A, Gilad S, Gilman R, Glamazdin A, Glashausser C, Glöckle W, Golak J, Goldberg E, Gomez J, Gorbenko V, Hansen JO, Hersman B, Holmes R, Huber GM, Hughes E, Humensky B, Incerti S, Iodice M, Jensen S, Jiang X, Jones C, Jones G, Jones M, Jutier C, Kamada H, Ketikyan A, Kominis I, Korsch W, Kramer K, Kumar K, Kumbartzki G, Kuss M, Lakuriqi E, Laveissiere G, Lerose JJ, Liang M, Liyanage N, Lolos G, Malov S, Marroncle J, McCormick K, McKeown RD, Meziani ZE, Michaels R, Mitchell J, Nogga A, Pace E, Papandreou Z, Pavlin T, Petratos GG, Pripstein D, Prout D, Ransome R, Roblin Y, Rowntree D, Rvachev M, Sabatié F, Saha A, Salmè G, Scopetta S, Skibiński R, Souder P, Saito T, Strauch S, Suleiman R, Takahashi K, Teijiro S, Todor L, Tsubota H, Ueno H, Urciuoli G, Van der Meer R, Vernin P, Voskanian H, Witała H, Wojtsekhowski B, Xiong F, Xu W, Yang JC, Zhang B, Zolnierczuk P. 3He spin-dependent cross sections and sum rules. PHYSICAL REVIEW LETTERS 2008; 101:022303. [PMID: 18764175 DOI: 10.1103/physrevlett.101.022303] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Indexed: 05/26/2023]
Abstract
We present a measurement of the spin-dependent cross sections for the 3He over -->(e over -->,e')X reaction in the quasielastic and resonance regions at a four-momentum transfer 0.1< or =Q2< or =0.9 GeV2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Chetluru V, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Harnarine I, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Richardson E, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Szostak A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Willhelm D, Wolfs FLH, Wosiek B, Woźniak K, Wyngaardt S, Wysłouch B. System size, energy, pseudorapidity, and centrality dependence of elliptic flow. PHYSICAL REVIEW LETTERS 2007; 98:242302. [PMID: 17677957 DOI: 10.1103/physrevlett.98.242302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Indexed: 05/16/2023]
Abstract
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.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Budzanowski A, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Hauer M, Heintzelman GA, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Katzy J, Khan N, Kucewicz W, Kulinich P, Kuo CM, Lin WT, Manly S, McLeod D, Mignerey AC, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Remsberg LP, Reuter M, Roland C, Roland G, Rosenberg L, Sagerer J, Sarin P, Sawicki P, Seals H, Sedykh I, Skulski W, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tang JL, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wuosmaa AH, Wysłouch B. Energy dependence of directed flow over a wide range of pseudorapidity in Au + Au collisions at the BNL Relativistic Heavy Ion Collider. PHYSICAL REVIEW LETTERS 2006; 97:012301. [PMID: 16907368 DOI: 10.1103/physrevlett.97.012301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Indexed: 05/11/2023]
Abstract
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.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bindel R, Busza W, Chai Z, Chetluru V, García E, Gburek T, Gulbrandsen K, Hamblen J, Harnarine I, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Kane JL, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Richardson E, Roland C, Roland G, Sagerer J, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Szostak A, Tonjes MB, Trzupek A, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Willhelm D, Wolfs FLH, Wosiek B, Woźniak K, Wyngaardt S, Wysłouch B. System size and centrality dependence of charged hadron transverse momentum spectra in Au + Au and Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. PHYSICAL REVIEW LETTERS 2006; 96:212301. [PMID: 16803231 DOI: 10.1103/physrevlett.96.212301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Indexed: 05/10/2023]
Abstract
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.
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Kelly JJ, Roché RE, Chai Z, Jones MK, Gayou O, Sarty AJ, Frullani S, Aniol K, Beise EJ, Benmokhtar F, Bertozzi W, Boeglin WU, Botto T, Brash EJ, Breuer H, Brown E, Burtin E, Calarco JR, Cavata C, Chang CC, Chant NS, Chen JP, Coman M, Crovelli D, De Leo R, Dieterich S, Escoffier S, Fissum KG, Garde V, Garibaldi F, Georgakopoulus S, Gilad S, Gilman R, Glashausser C, Hansen JO, Higinbotham DW, Hotta A, Huber GM, Ibrahim H, Iodice M, de Jager CW, Jiang X, Klimenko A, Kozlov A, Kumbartzki G, Kuss M, Lagamba L, Laveissière G, Lerose JJ, Lindgren RA, Liyanage N, Lolos GJ, Lourie RW, Margaziotis DJ, Marie F, Markowitz P, McAleer S, Meekins D, Michaels R, Milbrath BD, Mitchell J, Nappa J, Neyret D, Perdrisat CF, Potokar M, Punjabi VA, Pussieux T, Ransome RD, Roos PG, Rvachev M, Saha A, Sirca S, Suleiman R, Strauch S, Templon JA, Todor L, Ulmer PE, Urciuoli GM, Weinstein LB, Wijesooriya K, Wojtsekhowski B, Zheng X, Zhu L. Recoil polarization for delta excitation in pion electroproduction. PHYSICAL REVIEW LETTERS 2005; 95:102001. [PMID: 16196919 DOI: 10.1103/physrevlett.95.102001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2005] [Indexed: 05/04/2023]
Abstract
We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W = 1.23 GeV at Q(2) = 1.0 (GeV/c)(2), obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interference products well, indicating the need for adjusting magnitudes and phases for nonresonant amplitudes. We performed a nearly model-independent multipole analysis and obtained values for Re (S(1+)/M(1+)) = -(6.84 +/- 0.15)% and Re (E(1+)/M(1+)) = -(2.91 +/- 0.19)% that are distinctly different from those from the traditional Legendre analysis based upon M1+ dominance and ll(pi) < or = 1 truncation.
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Rvachev MM, Benmokhtar F, Penel-Nottaris E, Aniol KA, Bertozzi W, Boeglin WU, Butaru F, Calarco JR, Chai Z, Chang CC, Chen JP, Chudakov E, Cisbani E, Cochran A, Cornejo J, Dieterich S, Djawotho P, Duran W, Epstein MB, Finn JM, Fissum KG, Frahi-Amroun A, Frullani S, Furget C, Garibaldi F, Gayou O, Gilad S, Gilman R, Glashausser C, Hansen JO, Higinbotham DW, Hotta A, Hu B, Iodice M, Iomni R, de Jager CW, Jiang X, Jones MK, Kelly JJ, Kox S, Kuss M, Laget JM, De Leo R, Lerose JJ, Liatard E, Lindgren R, Liyanage N, Lourie RW, Malov S, Margaziotis DJ, Markowitz P, Merchez F, Michaels R, Mitchell J, Mougey J, Perdrisat CF, Punjabi VA, Quéméner G, Ransome RD, Réal JS, Roché R, Sabatié F, Saha A, Simon D, Strauch S, Suleiman R, Tamae T, Templon JA, Tieulent R, Ueno H, Ulmer PE, Urciuoli GM, Voutier E, Wijesooriya K, Wojtsekhowski B. Quasielastic 3He(e,e'p)2H reaction at Q2 = 1.5 GeV2 for recoil momenta up to 1 GeV/c. PHYSICAL REVIEW LETTERS 2005; 94:192302. [PMID: 16090165 DOI: 10.1103/physrevlett.94.192302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Indexed: 05/03/2023]
Abstract
We have studied the quasielastic 3He(e,e(')p)2H reaction in perpendicular coplanar kinematics, with the energy and the momentum transferred by the electron fixed at 840 MeV and 1502 MeV/c, respectively. The 3He(e,e(')p)2H cross section was measured for missing momenta up to 1000 MeV/c, while the A(TL) asymmetry was extracted for missing momenta up to 660 MeV/c. For missing momenta up to 150 MeV/c, the cross section is described by variational calculations using modern 3He wave functions. For missing momenta from 150 to 750 MeV/c, strong final-state interaction effects are observed. Near 1000 MeV/c, the experimental cross section is more than an order of magnitude larger than predicted by available theories. The A(TL) asymmetry displays characteristic features of broken factorization with a structure that is similar to that generated by available models.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Budzanowski A, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Hauer M, Heintzelman GA, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Katzy J, Khan N, Kucewicz W, Kulinich P, Kuo CM, Lin WT, Manly S, McLeod D, Mignerey AC, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Remsberg LP, Reuter M, Roland C, Roland G, Rosenberg L, Sagerer J, Sarin P, Sawicki P, Seals H, Sedykh I, Skulski W, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tang JL, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wuosmaa AH, Wysłouch B. Energy dependence of elliptic flow over a large pseudorapidity range in Au+Au collisions at the BNL relativistic heavy ion collider. PHYSICAL REVIEW LETTERS 2005; 94:122303. [PMID: 15903910 DOI: 10.1103/physrevlett.94.122303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2004] [Indexed: 05/02/2023]
Abstract
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.
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Benmokhtar F, Rvachev MM, Penel-Nottaris E, Aniol KA, Bertozzi W, Boeglin WU, Butaru F, Calarco JR, Chai Z, Chang CC, Chen JP, Chudakov E, Cisbani E, Cochran A, Cornejo J, Dieterich S, Djawotho P, Duran W, Epstein MB, Finn JM, Fissum KG, Frahi-Amroun A, Frullani S, Furget C, Garibaldi F, Gayou O, Gilad S, Gilman R, Glashausser C, Hansen JO, Higinbotham DW, Hotta A, Hu B, Iodice M, Iomni R, de Jager CW, Jiang X, Jones MK, Kelly JJ, Kox S, Kuss M, Laget JM, De Leo R, Lerose JJ, Liatard E, Lindgren R, Liyanage N, Lourie RW, Malov S, Margaziotis DJ, Markowitz P, Merchez F, Michaels R, Mitchell J, Mougey J, Perdrisat CF, Punjabi VA, Quéméner G, Ransome RD, Réal JS, Roché R, Sabatié F, Saha A, Simon D, Strauch S, Suleiman R, Tamae T, Templon JA, Tieulent R, Ueno H, Ulmer PE, Urciuoli GM, Voutier E, Wijesooriya K, Wojtsekhowski B. Measurement of the 3He(e,e'p)pn reaction at high missing energies and momenta. PHYSICAL REVIEW LETTERS 2005; 94:082305. [PMID: 15783882 DOI: 10.1103/physrevlett.94.082305] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Indexed: 05/24/2023]
Abstract
Results of the Jefferson Lab Hall A quasielastic 3He(e,e'p)pn measurements are presented. These measurements were performed at fixed transferred momentum and energy, q=1502 MeV/c and omega=840 MeV, respectively, for missing momenta p(m) up to 1 GeV/c and missing energies in the continuum region, up to pion threshold; this kinematic coverage is much more extensive than that of any previous experiment. The cross section data are presented along with the effective momentum density distribution and compared to theoretical models.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Lin WT, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wysłouch B. Centrality dependence of charged hadron transverse momentum spectra in Au+Au collisions from sqrt[s(NN)]=62.4 to 200 GeV. PHYSICAL REVIEW LETTERS 2005; 94:082304. [PMID: 15783881 DOI: 10.1103/physrevlett.94.082304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2004] [Indexed: 05/24/2023]
Abstract
We have measured transverse momentum distributions of charged hadrons produced in Au+Au collisions at sqrt[s(NN)]=62.4 GeV. The spectra are presented for transverse momenta 0.25<p(T)<4.5 GeV/c, in a pseudorapidity range of 0.2<eta<1.4. The nuclear modification factor R(AA) is calculated relative to p+p data at the same collision energy as a function of collision centrality. For 2<p(T)<4.5 GeV/c, R(AA) is found to be significantly larger than in Au+Au collisions at sqrt[s(NN)]= 130 and 200 GeV. In contrast to the large change in R(AA), we observe a very similar centrality evolution of the p(T) spectra at sqrt[s(NN)]=62.4 and 200 GeV. The dynamical origin of this surprising factorization of energy and centrality dependence of particle production in heavy-ion collisions remains to be understood.
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Amarian M, Auerbach L, Averett T, Berthot J, Bertin P, Bertozzi W, Black T, Brash E, Brown D, Burtin E, Calarco J, Cates G, Chai Z, Chen JP, Choi S, Chudakov E, Cisbani E, de Jager CW, Deur A, DiSalvo R, Dieterich S, Djawotho P, Finn JM, Fissum K, Fonvieille H, Frullani S, Gao H, Gao J, Garibaldi F, Gasparian A, Gilad S, Gilman R, Glamazdin A, Glashausser C, Goldberg E, Gomez J, Gorbenko V, Hansen JO, Hersman B, Holmes R, Huber GM, Hughes E, Humensky B, Incerti S, Iodice M, Jensen S, Jiang X, Jones C, Jones G, Jones M, Jutier C, Ketikyan A, Kominis I, Korsch W, Kramer K, Kumar K, Kumbartzki G, Kuss M, Lakuriqi E, Laveissiere G, Lerose J, Liang M, Liyanage N, Lolos G, Malov S, Marroncle J, McCormick K, McKeown R, Meziani ZE, Michaels R, Mitchell J, Papandreou Z, Pavlin T, Petratos GG, Pripstein D, Prout D, Ransome R, Roblin Y, Rowntree D, Rvachev M, Sabatie F, Saha A, Slifer K, Souder P, Saito T, Strauch S, Suleiman R, Takahashi K, Teijiro S, Todor L, Tsubota H, Ueno H, Urciuoli G, Van der Meer R, Vernin P, Voskanian H, Wojtsekhowski B, Xiong F, Xu W, Yang JC, Zhang B, Zołnierczuk PA. Measurement of the generalized forward spin polarizabilities of the neutron. PHYSICAL REVIEW LETTERS 2004; 93:152301. [PMID: 15524867 DOI: 10.1103/physrevlett.93.152301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Indexed: 05/24/2023]
Abstract
The generalized forward spin polarizabilities gamma(0) and delta(LT) of the neutron have been extracted for the first time in a Q2 range from 0.1 to 0.9 GeV2. Since gamma(0) is sensitive to nucleon resonances and delta(LT) is insensitive to the Delta resonance, it is expected that the pair of forward spin polarizabilities should provide benchmark tests of the current understanding of the chiral dynamics of QCD. The new results on delta(LT) show significant disagreement with chiral perturbation theory calculations, while the data for gamma(0) at low Q2 are in good agreement with a next-to-leading-order relativistic baryon chiral perturbation theory calculation. The data show good agreement with the phenomenological MAID model.
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Amarian M, Auerbach L, Averett T, Berthot J, Bertin P, Bertozzi B, Black T, Brash E, Brown D, Burtin E, Calarco J, Cates G, Chai Z, Chen JP, Choi S, Chudakov E, Cisbani E, De Jager CW, Deur A, DiSalvo R, Dieterich S, Djawotho P, Finn M, Fissum K, Fonvieille H, Frullani S, Gao H, Gao J, Garibaldi F, Gasparian A, Gilad S, Gilman R, Glamazdin A, Glashausser C, Goldberg E, Gomez J, Gorbenko V, Hansen JO, Hersman B, Holmes R, Huber GM, Hughes E, Humensky B, Incerti S, Iodice M, Jensen S, Jiang X, Jones C, Jones G, Jones M, Jutier C, Ketikyan A, Kominis I, Korsch W, Kramer K, Kumar K, Kumbartzki G, Kuss M, Lakuriqi E, Laveissiere G, Lerose J, Liang M, Liyanage N, Lolos G, Malov S, Marroncle J, McCormick K, McKeown R, Meziani ZE, Michaels R, Mitchell J, Papandreou Z, Pavlin T, Petratos GG, Pripstein D, Prout D, Ransome R, Roblin Y, Rowntree D, Rvachev M, Sabatie F, Saha A, Slifer K, Souder P, Saito T, Strauch S, Suleiman R, Takahashi K, Teijiro S, Todor L, Tsubota H, Ueno H, Urciuoli G, Van Der Meer R, Vernin P, Voskanian H, Wojtsekhowski B, Xiong F, Xu W, Yang JC, Zhang B, Zolnierczuk P. Q2 evolution of the neutron spin structure moments using a 3He target. PHYSICAL REVIEW LETTERS 2004; 92:022301. [PMID: 14753931 DOI: 10.1103/physrevlett.92.022301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Indexed: 05/24/2023]
Abstract
We have measured the spin structure functions g(1) and g(2) of 3He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.058 GeV off a polarized 3He target at a 15.5 degrees scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the Q2 evolution of Gamma(1)(Q2)= integral (1)(0)g(1)(x,Q2)dx, Gamma(2)(Q2)= integral (1)(0)g(2)(x,Q2)dx, and d(2)(Q2)= integral (1)(0)x(2)[2g(1)(x,Q2)+3g(2)(x,Q2)]dx for the neutron in the range 0.1< or =Q2< or =0.9 GeV2 with good precision. Gamma(1)(Q2) displays a smooth variation from high to low Q2. The Burkhardt-Cottingham sum rule holds within uncertainties and d(2) is nonzero over the measured range.
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Zheng X, Aniol K, Armstrong DS, Averett TD, Bertozzi W, Binet S, Burtin E, Busato E, Butuceanu C, Calarco J, Camsonne A, Cates GD, Chai Z, Chen JP, Choi S, Chudakov E, Cusanno F, Leo RD, Deur A, Dieterich S, Dutta D, Finn JM, Frullani S, Gao H, Gao J, Garibaldi F, Gilad S, Gilman R, Gomez J, Hansen JO, Higinbotham DW, Hinton W, Horn T, De Jager CW, Jiang X, Kaufman L, Kelly J, Korsch W, Kramer K, LeRose J, Lhuillier D, Liyanage N, Margaziotis DJ, Marie F, Markowitz P, McCormick K, Meziani ZE, Michaels R, Moffit B, Nanda S, Neyret D, Phillips SK, Powell A, Pussieux T, Reitz B, Roche J, Roche R, Roedelbronn M, Ron G, Rvachev M, Saha A, Savvinov N, Singh J, Sirca S, Slifer K, Solvignon P, Souder P, Steiner DJ, Strauch S, Sulkosky V, Tobias A, Urciuoli G, Vacheret A, Wojtsekhowski B, Xiang H, Xiao Y, Xiong F, Zhang B, Zhu L, Zhu X, Zołnierczuk PA. Precision measurement of the neutron spin asymmetryA(n)(1) and spin-flavor decomposition in the valence quark region. PHYSICAL REVIEW LETTERS 2004; 92:012004. [PMID: 14753984 DOI: 10.1103/physrevlett.92.012004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2003] [Indexed: 05/24/2023]
Abstract
We have measured the neutron spin asymmetry A(n)(1) with high precision at three kinematics in the deep inelastic region at x=0.33, 0.47, and 0.60, and Q(2)=2.7, 3.5, and 4.8 (GeV/c)(2), respectively. Our results unambiguously show, for the first time, that A(n)(1) crosses zero around x=0.47 and becomes significantly positive at x=0.60. Combined with the world proton data, polarized quark distributions were extracted. Our results, in general, agree with relativistic constituent quark models and with perturbative quantum chromodynamics (PQCD) analyses based on the earlier data. However they deviate from PQCD predictions based on hadron helicity conservation.
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Strauch S, Dieterich S, Aniol KA, Annand JRM, Baker OK, Bertozzi W, Boswell M, Brash EJ, Chai Z, Chen JP, Christy ME, Chudakov E, Cochran A, De Leo R, Ent R, Epstein MB, Finn JM, Fissum KG, Forest TA, Frullani S, Garibaldi F, Gasparian A, Gayou O, Gilad S, Gilman R, Glashausser C, Gomez J, Gorbenko V, Gueye PLJ, Hansen JO, Higinbotham DW, Hu B, Hyde-Wright CE, Ireland DG, Jackson C, de Jager CW, Jiang X, Jones C, Jones MK, Kellie JD, Kelly JJ, Keppel CE, Kumbartzki G, Kuss M, LeRose JJ, Livingston K, Liyanage N, Malov S, Margaziotis DJ, Meekins D, Michaels R, Mitchell JH, Nanda SK, Nappa J, Perdrisat CF, Punjabi VA, Ransome RD, Roché R, Rosner G, Rvachev M, Sabatie F, Saha A, Sarty A, Udias JM, Ulmer PE, Urciuoli GM, van den Brand JFJ, Vignote JR, Watts DP, Weinstein LB, Wijesooriya K, Wojtsekhowski B. Polarization transfer in the 4He(e-->,e'p-->)3H reaction up to Q2=2.6 (GeV/c)2. PHYSICAL REVIEW LETTERS 2003; 91:052301. [PMID: 12906589 DOI: 10.1103/physrevlett.91.052301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2002] [Revised: 05/05/2003] [Indexed: 05/24/2023]
Abstract
We have measured the proton recoil polarization in the 4He(e-->,e(')p-->)4H reaction at Q(2)=0.5, 1.0, 1.6, and 2.6 (GeV/c)(2). The measured ratio of polarization transfer coefficients differs from a fully relativistic calculation, favoring the inclusion of a medium modification of the proton form factors predicted by a quark-meson coupling model. In addition, the measured induced polarizations agree reasonably well with the fully relativistic calculation indicating that the treatment of final-state interactions is under control.
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Amarian M, Auerbach L, Averett T, Berthot J, Bertin P, Bertozzi W, Black T, Brash E, Brown D, Burtin E, Calarco JR, Cates GD, Chai Z, Chen JP, Choi S, Chudakov E, Cisbani E, De Jager CW, Deur A, DiSalvo R, Dieterich S, Djawotho P, Finn M, Fissum K, Fonvieille H, Frullani S, Gao H, Gao J, Garibaldi F, Gasparian A, Gilad S, Gilman R, Glamazdin A, Glashausser C, Goldberg E, Gomez J, Gorbenko V, Hansen JO, Hersman FW, Holmes R, Huber GM, Hughes EW, Humensky TB, Incerti S, Iodice M, Jensen S, Jiang X, Jones C, Jones GM, Jones M, Jutier C, Ketikyan A, Kominis I, Korsch W, Kramer K, Kumar KS, Kumbartzki G, Kuss M, Lakuriqi E, Laveissiere G, Lerose J, Liang M, Liyanage N, Lolos G, Malov S, Marroncle J, McCormick K, McKeown R, Meziani ZE, Michaels R, Mitchell J, Papandreou Z, Pavlin T, Petratos GG, Pripstein D, Prout D, Ransome R, Roblin Y, Rowntree D, Rvachev M, Sabatie F, Saha A, Slifer K, Souder PA, Saito T, Strauch S, Suleiman R, Takahashi K, Teijiro S, Todor L, Tsubota H, Ueno H, Urciuoli G, Van Der Meer R, Vernin P, Voskanian H, Wojtsekhowski B, Xiong F, Xu W, Yang JC, Zhang B, Zolnierczuk P. Q2 evolution of the generalized Gerasimov-Drell-Hearn integral for the neutron using a 3He target. PHYSICAL REVIEW LETTERS 2002; 89:242301. [PMID: 12484938 DOI: 10.1103/physrevlett.89.242301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2002] [Indexed: 05/24/2023]
Abstract
We present data on the inclusive scattering of polarized electrons from a polarized 3He target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5 degrees. Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference sigma(1/2)-sigma(3/2). We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q2 of 0.1-0.9 GeV2.
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Cai X, Chai Z, Jing Z, Wang P, Luo X, Chen J, Dou Y, Feng S, Su C, Jin J. Studies on the development of DNA vaccine against Cysticercus cellulosae infection and its efficacy. THE SOUTHEAST ASIAN JOURNAL OF TROPICAL MEDICINE AND PUBLIC HEALTH 2002; 32 Suppl 2:105-10. [PMID: 12041570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
DNA vaccine against Cysticercus cellulosae infection was developed and its efficacy was tested. A pair of primers specific to antigen B gene of C. cellulosae was designed which amplified the gene successfully with RT-PCR. The gene was ligated to PV93 vector, and the recombinant of antigen B gene and PV93 was transformed to JM83 cells. The transformed JM83 cells were cultured in a large scale and the plasmid purified. Based on the recombinant plasmid. a DNA vaccine was developed and used to vaccinate two groups of experimental pigs. In each group, there was a routine vaccine, an enhanced vaccine and a control group. Groups 1 and 2 were challenged at 4 months and at 14 days post vaccination respectively with eggs of Taenia solium. The antibody response was also tested with ELISA. The results suggested that all animals vaccinated AgB gene DNA vaccine, no matter by routine or enhanced vaccine, their antibodies reached maximum peak 23 days post vaccination and decreased gradually. When the animals were challenged 4 months after vaccination, they had strong immunity and the parasites decrease rates were 91.2% and 93.1% respectively. When pigs vaccinated with AgB gene DNA vaccine were challenged 14 days post vaccination with 18,000 eggs/pig. The animals showed strong immunity and the parasite decrease rates were 99.5% and 84.9% respectively. However at that time, the antibodies did not reach the peak. While in the control group, the number of C. cellulosae was as many as 2,500. It was concluded that the pigs vaccinated with DNA vaccine had strong immunity against infection of eggs of T. solium.
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Shi F, Ye H, Chai Z. Clinicopathological study on phyllodes tumor of the breast. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2002; 31:208-12. [PMID: 12475436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the relationship between pathological features and classification criteria of the breast Phyllodes tumor. METHODS 203 cases of breast phyllodes tumor diagnosed in 22 hospitals since 1956 were analyzed and reappraised by a retrospective study. RESULTS 133 cases were benign, 42 cases were borderline and 28 were malignant. The follow-up (6 to 372 months) showed that 28/133 benign, 19/42 borderline and 18/28 malignant cases recurred, and 17 patients (2 borderline and 15 malignant) died. The statistic cluster analysis demonstrated that stromal cellar atypia, margin involvement, mitotic activity and tumor necrosis were retained in the variable group, and no error distinguish were showed. CONCLUSIONS The breast phyllodes tumor can be classified as the following three types: benign, borderline and malignant. It is important to diagnose and classify the breast phyllodes tumor according to the involvement of tumor margin, stromal cellar atypia, mitotic activity, stromal overgrowth and tumor necrosis. There are significant differences of 5 years survival rates, recurrent rates and death rates between the benign, borderline and malignant breast phyllodes tumor. With wide excision the recurrence of the tumor decreased suggesting that broad excision is preferred for the benign phyllodes tumor and mastectomy is indicated for recurred borderline and malignant tumors.
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Gayou O, Aniol KA, Averett T, Benmokhtar F, Bertozzi W, Bimbot L, Brash EJ, Calarco JR, Cavata C, Chai Z, Chang CC, Chang T, Chen JP, Chudakov E, De Leo R, Dieterich S, Endres R, Epstein MB, Escoffier S, Fissum KG, Fonvieille H, Frullani S, Gao J, Garibaldi F, Gilad S, Gilman R, Glamazdin A, Glashausser C, Gomez J, Gorbenko V, Hansen JO, Higinbotham DW, Huber GM, Iodice M, de Jager CW, Jiang X, Jones MK, Kelly JJ, Khandaker M, Kozlov A, Kramer KM, Kumbartzki G, LeRose JJ, Lhuillier D, Lindgren RA, Liyanage N, Lolos GJ, Margaziotis DJ, Marie F, Markowitz P, McCormick K, Michaels R, Milbrath BD, Nanda SK, Neyret D, Papandreou Z, Pentchev L, Perdrisat CF, Piskunov NM, Punjabi V, Pussieux T, Quéméner G, Ransome RD, Raue BA, Roché R, Rvachev M, Saha A, Salgado C, Sirca S, Sitnik I, Strauch S, Todor L, Tomasi-Gustafsson E, Urciuoli GM, Voskanyan H, Wijesooriya K, Wojtsekhowski BB, Zheng X, Zhu L. Measurement of G(E(p))/G(M(p)) in e(-->)p---> e(-->)p to Q(2) = 5.6 GeV(2). PHYSICAL REVIEW LETTERS 2002; 88:092301. [PMID: 11863996 DOI: 10.1103/physrevlett.88.092301] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2001] [Indexed: 05/23/2023]
Abstract
The ratio of the electric and magnetic form factors of the proton G(E(p))/G(M(p)), which is an image of its charge and magnetization distributions, was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the recoil polarization technique. The ratio of the form factors is directly proportional to the ratio of the transverse to longitudinal components of the polarization of the recoil proton in the elastic e(-->)p---> e(-->)p reaction. The new data presented span the range 3.5< Q(2)< 5.6 GeV(2) and are well described by a linear Q(2) fit. Also, the ratio sqrt[Q(2)] F(2(p))/F(1(p)) reaches a constant value above Q(2) = 2 GeV(2).
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Feng W, Qian Q, Ding W, Chai Z. Tissue contents and subcellular distribution of chromium and other trace metals in experimental diabetic rats after intravenous injection of Cr 50-enriched stable isotopic tracer solution. Metabolism 2001; 50:1168-74. [PMID: 11586488 DOI: 10.1053/meta.2001.26760] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In order to study the metabolism of essential trace elements in diabetics, we studied alloxan-diabetic rats for the distribution patterns of chromium (Cr), cobalt (Co), iron (Fe), selenium (Se), and zinc (Zn) in the liver, kidney, pancreas, and testes, as well as in the organ subcellular fractions. Normal rats were used as controls. Cr 50-enriched stable isotopic tracer solution was given by intravenous injection to avoid the difficulties of estimation of Cr status. Our data show that the concentrations of Zn in liver and kidney, of Co, Fe, and Zn in pancreas, and of Fe and Zn in testes of the diabetic rats were significantly higher than in the control rats. Nevertheless, the concentrations of Cr in pancreas, Fe in kidney, and Cr and Se in testes of the diabetic rats were significantly lower than in the controls. Furthermore, we observed significant alterations of element concentrations in subcellular fractions of various organs in the diabetic rats. These results suggest that changing hormone levels may interfere with the accumulation of some trace elements both in the organs and in the subcellular fractions of rats.
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Liu J, Zhang B, He X, Zhang P, Chai Z. Selection of a high-biomass, chromium-rich yeast strain and optimization of cultivation conditions. J Ind Microbiol Biotechnol 2001; 27:195-8. [PMID: 11687929 DOI: 10.1038/sj.jim.7000161] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2001] [Accepted: 06/11/2001] [Indexed: 11/09/2022]
Abstract
Saccharomyces cerevisiae LZ-53 was selected from 240 primary yeast strains from different genera and species, whose chromium (Cr) resistance and biomass were higher than others were. The highest biomass and Cr content of the strain was obtained in 30 h at 28 degrees C and 200 rpm, when 20 ml of the culture in 250-ml shake flasks was grown in wort containing 1200 microg/ml Cr. The initial pH was adjusted to 6.0. The optimal inoculum volume was 10% (v/v). The Cr content of the cells was determined by neutron activation analysis. Under the optimized cultivation conditions, the Cr content reached 3248 microg/g.
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Chai Z, Sarcevic B, Mawson A, Toh BH. SET-related cell division autoantigen-1 (CDA1) arrests cell growth. J Biol Chem 2001; 276:33665-74. [PMID: 11395479 DOI: 10.1074/jbc.m007681200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We used an autoimmune serum from a patient with discoid lupus erythematosus to clone a cDNA of 2808 base pairs. Its open reading frame of 2079 base pairs encodes a predicted polypeptide of 693 amino acids named CDA1 (cell division autoantigen-1). CDA1 has a predicted molecular mass of 79,430 Daltons and a pI of 4.26. The size of the cDNA is consistent with its estimated mRNA size. CDA1 comprises an N-terminal proline-rich domain, a central basic domain, and a C-terminal bipartite acidic domain. It has four putative nuclear localization signals and potential sites for phosphorylation by cAMP and cGMP-dependent kinases, protein kinase C, thymidine kinase, casein kinase II, and cyclin-dependent kinases (CDKs). CDA1 is phosphorylated in HeLa cells and by cyclin D1/CDK4, cyclin A/CDK2, and cyclin B/CDK1 in vitro. Its basic and acidic domains contain regions homologous to almost the entire human leukemia-associated SET protein. The same basic region is also homologous to nucleosome assembly proteins, testis TSPY protein, and an uncharacterized brain protein. CDA1 is present in the nuclear fraction of HeLa cells and localizes to the nucleus and nucleolus in HeLa cells transfected with CDA1 or its N terminus containing all four nuclear localization signals. Its acidic C terminus localizes mainly to the cytoplasm. CDA1 levels are low in serum-starved cells, increasing dramatically with serum stimulation. Expression of the CDA1 transgene, but not its N terminus, arrests HeLa cell growth, colony numbers, cell density, and bromodeoxyuridine uptake in a dose-dependent manner. The ability of CDA1 to arrest cell growth is abolished by mutation of the two CDK consensus phosphorylation sites. We propose that CDA1 is a negative regulator of cell growth and that its activity is regulated by its expression level and phosphorylation.
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MESH Headings
- Amino Acid Sequence
- Autoantigens/chemistry
- Autoantigens/physiology
- Base Sequence
- Binding Sites
- Blotting, Northern
- Bromodeoxyuridine/metabolism
- Cell Division
- Cell Membrane/metabolism
- Cell Nucleolus/metabolism
- Cell Nucleus/metabolism
- Chromosomal Proteins, Non-Histone
- Cloning, Molecular
- Cyclic AMP/metabolism
- Cyclic GMP/metabolism
- DNA/metabolism
- DNA, Complementary/metabolism
- DNA-Binding Proteins
- Doxycycline/pharmacology
- Fluorescent Antibody Technique, Indirect
- HeLa Cells
- Histone Chaperones
- Humans
- Immunoblotting
- Lupus Erythematosus, Discoid/genetics
- Lupus Erythematosus, Discoid/metabolism
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Mutation
- Nuclear Localization Signals
- Phosphorylation
- Precipitin Tests
- Protein Kinase C/metabolism
- Protein Structure, Tertiary
- Proteins/chemistry
- Sequence Homology, Amino Acid
- Thymidine Kinase/metabolism
- Transcription Factors
- Transfection
- Transgenes
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Wijesooriya K, Afanasev A, Amarian M, Aniol K, Becher S, Benslama K, Bimbot L, Bosted P, Brash E, Calarco J, Chai Z, Chang CC, Chang T, Chen JP, Choi S, Chudakov E, Churchwell S, Crovelli D, Dieterich S, Dumalski S, Dutta D, Epstein M, Fissum K, Fox B, Frullani S, Gao H, Gao J, Garibaldi F, Gayou O, Gilman R, Glamazdin S, Glashausser C, Gomez J, Gorbenko V, Hansen O, Holt RJ, Hovdebo J, Huber GM, de Jager CW, Jiang X, Jones C, Jones MK, Kelly J, Kinney E, Kooijman E, Kumbartzki G, Kuss M, LeRose J, Liang M, Lindgren R, Liyanage N, Malov S, Margaziotis DJ, Markowitz P, McCormick K, Meekins D, Meziani ZE, Michaels R, Mitchell J, Morand L, Perdrisat CF, Pomatsalyuk R, Punjabi V, Ransome RD, Roche R, Rvachev M, Saha A, Sarty A, Schulte EC, Simon D, Strauch S, Suleiman R, Todor L, Ulmer PE, Urciuoli GM, Wojtsekhowski B, Xiong F, Xu W. Polarization measurements in high-energy deuteron photodisintegration. PHYSICAL REVIEW LETTERS 2001; 86:2975-2979. [PMID: 11290086 DOI: 10.1103/physrevlett.86.2975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2000] [Revised: 12/19/2000] [Indexed: 05/23/2023]
Abstract
We present measurements of the recoil proton polarization for the d(gamma-->,p-->)n reaction at straight theta(c.m.) = 90 degrees for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization transfer with circularly polarized photons. The induced polarization p(y) vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(gamma,p)n cross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.
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Yang Z, Li H, Chai Z, Fullerton MJ, Cao Y, Toh BH, Funder JW, Liu JP. Dynamin II regulates hormone secretion in neuroendocrine cells. J Biol Chem 2001; 276:4251-60. [PMID: 11032832 DOI: 10.1074/jbc.m006371200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The dynamin family of GTP-binding proteins has been implicated as playing an important role in endocytosis. In Drosophila shibire, mutations of the single dynamin gene cause blockade of endocytosis and neurotransmitter release, manifest as temperature-sensitive neuromuscular paralysis. Mammals express three dynamin genes: the neural specific dynamin I, ubiquitous dynamin II, and predominantly testicular dynamin III. Mutations of dynamin I result in a blockade of synaptic vesicle recycling and receptor-mediated endocytosis. Here, we show that dynamin II plays a key role in controlling constitutive and regulated hormone secretion from mouse pituitary corticotrope (AtT20) cells. Dynamin II is preferentially localized to the Golgi apparatus where it interacts with G-protein betagamma subunit and regulates secretory vesicle release. The presence of dynamin II at the Golgi apparatus and its interaction with the betagamma subunit are mediated by the pleckstrin homology domain of the GTPase. Overexpression of the pleckstrin homology domain, or a dynamin II mutant lacking the C-terminal SH3-binding domain, induces translocation of endogenous dynamin II from the Golgi apparatus to the plasma membrane and transformation of dynamin II from activity in the secretory pathway to receptor-mediated endocytosis. Thus, dynamin II regulates secretory vesicle formation from the Golgi apparatus and hormone release from mammalian neuroendocrine cells.
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Li W, Cai X, Wang J, Chen G, Chai Z. Early monitoring of P(ti)O(2), P(ti)CO(2), pH and brain temperature in patients with brain injuries and the clinical significance. Chin J Traumatol 2001; 4:20-4. [PMID: 11835703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To explore the regulation of early brain tissue metabolic changing after brain injuries and the clinical significance. METHODS There were 17 patients with brain injuries. Early dire ct monitoring of P(ti)O(2), P(ti)CO(2), pH and brain temperature, dynamic observation of the relation between various parameters and clinics after brain injuries were performed. RESULTS Early changes of P(ti)O(2), P(ti)CO(2) and pH were closely correlated with outcome. The death rate obviously increased when P(ti)O(2) was continuously lower than 9 mmHg within 24 hours after injuries. Secondary brain injury prolonged and aggravated brain tissue metabolic disturbance. When intracerebral pressure was over 30 mmHg P(ti)O(2) began to decrease. The brain temperature in brain death patients was evidently lower than axillary temperature. CONCLUSIONS The direct monitoring of P(ti)O(2), P(ti)CO(2), pH and brain temperature is safe and accurate and can find early anoxia da mage to brain tissue and provide reliable basis for clinical therapy. It ha s an instructive significance in selecting and studying a new treatment method in brain injuries. And it can be taken as a criterion in clinical judging brain deaths.
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50
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Tsukada Y, Ichikawa H, Chai Z, Lai FP, Dunster K, Sentry JW, Toh BH. Novel variant of p230 trans-Golgi network protein identified by serum from Sjögren's syndrome patient. Eur J Cell Biol 2000; 79:790-4. [PMID: 11139141 DOI: 10.1078/0171-9335-00114] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Trans-Golgi network (TGN) protein p230 is a peripheral membrane protein associated with the cytoplasmic face of the TGN. TGNp230 is an extensively coiled-coil protein with flexible amino- and carboxyl-terminal ends, associates with non-clathrin-coated vesicles arising from the TGN, and is implicated in vesicle biogenesis. Here we used an autoimmune serum from a patient with S ogren's syndrome to clone partial cDNAs from a human hepatoma HepG2 expression library. The partial cDNAs encoded a novel amino-terminal splice variant of TGNp230. Specific reactivity of the autoimmune serum for p230 is supported by immunofluorescene staining of the Golgi apparatus, immunoblotting of a > 200-kDa HeLa cell protein, and reactivity with a bacterially expressed GST-p230 fusion protein. The alternative splicing occurs within the first proline-rich domain of p230. It comprises a deletion of 30 bp followed immediately by an additional 66 bp absent in the published sequence. RT-PCR analysis indicated that the splicing occurs independently of previously reported carboxyl-terminal splicing, and that this novel splice variant is more frequent than the previously reported p230. The novel splice variant of p230 is also located at the TGN. We propose that p230 splice variants may be implicated in selection of cargo molecules for vesicles arising from the TGN.
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