Noise, sampling, and the number of projections in cone-beam CT with a flat-panel detector

PURPOSE

To investigate the effect of the number of projection views on image noise in cone-beam CT (CBCT) with a flat-panel detector.

METHODS

This fairly fundamental consideration in CBCT system design and operation was addressed experimentally (using a phantom presenting a uniform medium as well as statistically motivated "clutter") and theoretically (using a cascaded systems model describing CBCT noise) to elucidate the contributing factors of quantum noise (σ(Q)), electronic noise (σ(E)), and view aliasing (σ(view)). Analysis included investigation of the noise, noise-power spectrum, and modulation transfer function as a function of the number of projections (N(proj)), dose (D(tot)), and voxel size (b(vox)).

RESULTS

The results reveal a nonmonotonic relationship between image noise and N(proj) at fixed total dose: for the CBCT system considered, noise decreased with increasing N(proj) due to reduction of view sampling effects in the regime N(proj) <~200, above which noise increased with N(proj) due to increased electronic noise. View sampling effects were shown to depend on the heterogeneity of the object in a direct analytical relationship to power-law anatomical clutter of the form κ/f(β)--and a general model of individual noise components (σ(Q), σ(E), and σ(view)) demonstrated agreement with measurements over a broad range in N(proj), D(tot), and b(vox).

CONCLUSIONS

The work elucidates fairly basic elements of CBCT noise in a manner that demonstrates the role of distinct noise components (viz., quantum, electronic, and view sampling noise). For configurations fairly typical of CBCT with a flat-panel detector (FPD), the analysis reveals a "sweet spot" (i.e., minimum noise) in the range N(proj) ~ 250-350, nearly an order of magnitude lower in N(proj) than typical of multidetector CT, owing to the relatively high electronic noise in FPDs. The analysis explicitly relates view aliasing and quantum noise in a manner that includes aspects of the object ("clutter") and imaging chain (including nonidealities of detector blur and electronic noise) to provide a more rigorous basis for commonly held intuition and heurism in CBCT system design and operation.

Healthcare resource utilization and costs in working-age patients with high-risk atherosclerotic cardiovascular disease: findings from a multi-employer claims database

OBJECTIVE

Patients with coronary artery disease with diabetes, a history of acute coronary syndromes, cerebrovascular atherosclerotic disease, or peripheral arterial disease are at particularly high risk for a cardiovascular (CV) event and can be defined as having high-risk atherosclerotic cardiovascular disease (ASCVD). The objective of this study is to examine healthcare resource utilization (HRU) and total healthcare costs (THC) for patients with ASCVD in a commercially insured population.

METHODS

A retrospective cohort study was conducted using a large, US employer-based, claims database. Patients with an ASCVD diagnosis between October 1, 2008 to September 30, 2009 who met eligibility requirements were included. All-cause and ASCVD-related HRU and THC for the first and second year of follow-up were examined for all patients and by the number of arterial beds affected. Adjusted THC were compared across groups with and without polyvascular disease.

RESULTS

The analysis included 152,290 patients with ASCVD. Use of CV-related medications, hospitalizations, and office visits were highest among patients with three arterial beds affected. Mean all-cause THC for patients with ASCVD were ∼$19,000 per patient in Year 1 or Year 2, with medical costs as the main driver. ASCVD-related THC were also similar for Year 1 ($8699) and Year 2 ($7925) across all patients. Adjusted all-cause and ASCVD-related THC for both years were greatest for patients with three affected arterial beds compared with one or two affected beds (p < 0.001 for each comparison).

CONCLUSIONS

This is the first study in a managed care setting to systematically estimate all-cause and ASCVD-related THC for an aggregated population of ASCVD patients at high risk for a CV event. The economic burden of ASCVD in working-age patients in the US is substantial. Significantly higher HRU and costs were found in patients with polyvascular disease compared with those with only one affected bed.

Denis RD, Staerz S, Stahlman J, Stamen R, Stamm S, Stanecka E, Stanek RW, Stanescu C, Stanescu-Bellu M, Stanitzki MM, Stapnes S, Starchenko EA, Stark J, Staroba P, Starovoitov P, Staszewski R, Stavina P, Steinberg P, Stelzer B, Stelzer HJ, Stelzer-Chilton O, Stenzel H, Stern S, Stewart GA, Stillings JA, Stockton MC, Stoebe M, Stoicea G, Stolte P, Stonjek S, Stradling AR, Straessner A, Stramaglia ME, Strandberg J, Strandberg S, Strandlie A, Strauss E, Strauss M, Strizenec P, Ströhmer R, Strom DM, Stroynowski R, Stucci SA, Stugu B, Styles NA, Su D, Su J, Subramaniam R, Succurro A, Sugaya Y, Suhr C, Suk M, Sulin VV, Sultansoy S, Sumida T, Sun S, Sun X, Sundermann JE, Suruliz K, Susinno G, Sutton MR, Suzuki Y, Svatos M, Swedish S, Swiatlowski M, Sykora I, Sykora T, Ta D, Taccini C, Tackmann K, Taenzer J, Taffard A, Tafirout R, Taiblum N, Takai H, Takashima R, Takeda H, Takeshita T, Takubo Y, Talby M, Talyshev AA, Tam JYC, Tan KG, Tanaka J, Tanaka R, Tanaka S, Tanaka S, Tanasijczuk AJ, Tannenwald BB, Tannoury N, Tapprogge S, Tarem S, Tarrade F, Tartarelli GF, Tas P, Tasevsky M, Tashiro T, Tassi E, Tavares Delgado A, Tayalati Y, Taylor FE, Taylor GN, Taylor W, Teischinger FA, Teixeira Dias Castanheira M, Teixeira-Dias P, Temming KK, Ten Kate H, Teng PK, Teoh JJ, Terada S, Terashi K, Terron J, Terzo S, Testa M, Teuscher RJ, Therhaag J, Theveneaux-Pelzer T, Thomas JP, Thomas-Wilsker J, Thompson EN, Thompson PD, Thompson PD, Thompson RJ, Thompson AS, Thomsen LA, Thomson E, Thomson M, Thong WM, Thun RP, Tian F, Tibbetts MJ, Tikhomirov VO, Tikhonov YA, Timoshenko S, Tiouchichine E, Tipton P, Tisserant S, Todorov T, Todorova-Nova S, Toggerson B, Tojo J, Tokár S, Tokushuku K, Tollefson K, Tomlinson L, Tomoto M, Tompkins L, Toms K, Topilin ND, Torrence E, Torres H, Torró Pastor E, Toth J, Touchard F, Tovey DR, Tran HL, Trefzger T, Tremblet L, Tricoli A, Trigger IM, Trincaz-Duvoid S, Tripiana MF, Trischuk W, Trocmé B, Troncon C, Trottier-McDonald M, Trovatelli M, True P, Trzebinski M, Trzupek A, Tsarouchas C, Tseng JCL, Tsiareshka PV, Tsionou D, Tsipolitis G, Tsirintanis N, Tsiskaridze S, Tsiskaridze V, Tskhadadze EG, Tsukerman II, Tsulaia V, Tsuno S, Tsybychev D, Tudorache A, Tudorache V, Tuna AN, Tupputi SA, Turchikhin S, Turecek D, Turk Cakir I, Turra R, Tuts PM, Tykhonov A, Tylmad M, Tyndel M, Uchida K, Ueda I, Ueno R, Ughetto M, Ugland M, Uhlenbrock M, Ukegawa F, Unal G, Undrus A, Unel G, Ungaro FC, Unno Y, Unverdorben C, Urbaniec D, Urquijo P, Usai G, Usanova A, Vacavant L, Vacek V, Vachon B, Valencic N, Valentinetti S, Valero A, Valery L, Valkar S, Valladolid Gallego E, Vallecorsa S, Valls Ferrer JA, Van Den Wollenberg W, Van Der Deijl PC, van der Geer R, van der Graaf H, Van Der Leeuw R, van der Ster D, van Eldik N, van Gemmeren P, Van Nieuwkoop J, van Vulpen I, van Woerden MC, Vanadia M, Vandelli W, Vanguri R, Vaniachine A, Vankov P, Vannucci F, Vardanyan G, Vari R, Varnes EW, Varol T, Varouchas D, Vartapetian A, Varvell KE, Vazeille F, Vazquez Schroeder T, Veatch J, Veloso F, Veneziano S, Ventura A, Ventura D, Venturi M, Venturi N, Venturini A, Vercesi V, Verducci M, Verkerke W, Vermeulen JC, Vest A, Vetterli MC, Viazlo O, Vichou I, Vickey T, Vickey Boeriu OE, Viehhauser GHA, Viel S, Vigne R, Villa M, Villaplana Perez M, Vilucchi E, Vincter MG, Vinogradov VB, Virzi J, Vivarelli I, Vives Vaque F, Vlachos S, Vladoiu D, Vlasak M, Vogel A, Vogel M, Vokac P, Volpi G, Volpi M, von der Schmitt H, von Radziewski H, von Toerne E, Vorobel V, Vorobev K, Vos M, Voss R, Vossebeld JH, Vranjes N, Vranjes Milosavljevic M, Vrba V, Vreeswijk M, Vu Anh T, Vuillermet R, Vukotic I, Vykydal Z, Wagner P, Wagner W, Wahlberg H, Wahrmund S, Wakabayashi J, Walder J, Walker R, Walkowiak W, Wall R, Waller P, Walsh B, Wang C, Wang C, Wang F, Wang H, Wang H, Wang J, Wang J, Wang K, Wang R, Wang SM, Wang T, Wang X, Wanotayaroj C, Warburton A, Ward CP, Wardrope DR, Warsinsky M, Washbrook A, Wasicki C, Watkins PM, Watson AT, Watson IJ, Watson MF, Watts G, Watts S, Waugh BM, Webb S, Weber MS, Weber SW, Webster JS, Weidberg AR, Weigell P, Weinert B, Weingarten J, Weiser C, Weits H, Wells PS, Wenaus T, Wendland D, Weng Z, Wengler T, Wenig S, Wermes N, Werner M, Werner P, Wessels M, Wetter J, Whalen K, White A, White MJ, White R, White S, Whiteson D, Wicke D, Wickens FJ, Wiedenmann W, Wielers M, Wienemann P, Wiglesworth C, Wiik-Fuchs LAM, Wijeratne PA, Wildauer A, Wildt MA, Wilkens HG, Will JZ, Williams HH, Williams S, Willis C, Willocq S, Wilson A, Wilson JA, Wingerter-Seez I, Winklmeier F, Winter BT, Wittgen M, Wittig T, Wittkowski J, Wollstadt SJ, Wolter MW, Wolters H, Wosiek BK, Wotschack J, Woudstra MJ, Wozniak KW, Wright M, Wu M, Wu SL, Wu X, Wu Y, Wulf E, Wyatt TR, Wynne BM, Xella S, Xiao M, Xu D, Xu L, Yabsley B, Yacoob S, Yakabe R, Yamada M, Yamaguchi H, Yamaguchi Y, Yamamoto A, Yamamoto K, Yamamoto S, Yamamura T, Yamanaka T, Yamauchi K, Yamazaki Y, Yan Z, Yang H, Yang H, Yang UK, Yang Y, Yanush S, Yao L, Yao WM, Yasu Y, Yatsenko E, Yau Wong KH, Ye J, Ye S, Yeletskikh I, Yen AL, Yildirim E, Yilmaz M, Yoosoofmiya R, Yorita K, Yoshida R, Yoshihara K, Young C, Young CJS, Youssef S, Yu DR, Yu J, Yu JM, Yu J, Yuan L, Yurkewicz A, Yusuff I, Zabinski B, Zaidan R, Zaitsev AM, Zaman A, Zambito S, Zanello L, Zanzi D, Zeitnitz C, Zeman M, Zemla A, Zengel K, Zenin O, Ženiš T, Zerwas D, Zevi della Porta G, Zhang D, Zhang F, Zhang H, Zhang J, Zhang L, Zhang X, Zhang Z, Zhao Z, Zhemchugov A, Zhong J, Zhou B, Zhou L, Zhou N, Zhu CG, Zhu H, Zhu J, Zhu Y, Zhuang X, Zhukov K, Zibell A, Zieminska D, Zimine NI, Zimmermann C, Zimmermann R, Zimmermann S, Zimmermann S, Zinonos Z, Ziolkowski M, Zobernig G, Zoccoli A, zur Nedden M, Zurzolo G, Zutshi V, Zwalinski L. Search for contact interactions and large extra dimensions in the dilepton channel using proton-proton collisions at [Formula: see text] 8 TeV with the ATLAS detector

A search is conducted for non-resonant new phenomena in dielectron and dimuon final states, originating from either contact interactions or large extra spatial dimensions. The LHC 2012 proton-proton collision dataset recorded by the ATLAS detector is used, corresponding to 20 fb[Formula: see text] at [Formula: see text] = 8 TeV. The dilepton invariant mass spectrum is a discriminating variable in both searches, with the contact interaction search additionally utilizing the dilepton forward-backward asymmetry. No significant deviations from the Standard Model expectation are observed. Lower limits are set on the [Formula: see text] contact interaction scale [Formula: see text] between 15.4 TeV and 26.3 TeV, at the 95 % credibility level. For large extra spatial dimensions, lower limits are set on the string scale [Formula: see text] between 3.2 TeV to 5.0 TeV.

Measurement of distributions sensitive to the underlying event in inclusive Z-boson production in [Formula: see text] collisions at [Formula: see text] TeV with the ATLAS detector

A measurement of charged-particle distributions sensitive to the properties of the underlying event is presented for an inclusive sample of events containing a [Formula: see text]-boson, decaying to an electron or muon pair. The measurement is based on data collected using the ATLAS detector at the LHC in proton-proton collisions at a centre-of-mass energy of [Formula: see text] TeV with an integrated luminosity of [Formula: see text] fb[Formula: see text]. Distributions of the charged particle multiplicity and of the charged particle transverse momentum are measured in regions of azimuthal angle defined with respect to the [Formula: see text]-boson direction. The measured distributions are compared to similar distributions measured in jet events, and to the predictions of various Monte Carlo generators implementing different underlying event models.

A measurement of the ratio of the production cross sections for [Formula: see text] and [Formula: see text] bosons in association with jets with the ATLAS detector

The ratio of the production cross sections for [Formula: see text] and [Formula: see text] bosons in association with jets has been measured in proton-proton collisions at [Formula: see text] with the ATLAS experiment at the Large Hadron Collider. The measurement is based on the entire 2011 dataset, corresponding to an integrated luminosity of [Formula: see text]. Inclusive and differential cross-section ratios for massive vector bosons decaying to electrons and muons are measured in association with jets with transverse momentum [Formula: see text] and jet rapidity [Formula: see text]. The measurements are compared to next-to-leading-order perturbative QCD calculations and to predictions from different Monte Carlo generators implementing leading-order matrix elements supplemented by parton showers.

Ultrahigh Brilliance Multi-MeV γ-Ray Beams from Nonlinear Relativistic Thomson Scattering

We report on the generation of a narrow divergence (θ_{γ}<2.5  mrad), multi-MeV (E_{max}≈18  MeV) and ultrahigh peak brilliance (>1.8×10^{20}  photons s^{-1} mm^{-2}  mrad^{-2} 0.1% BW) γ-ray beam from the scattering of an ultrarelativistic laser-wakefield accelerated electron beam in the field of a relativistically intense laser (dimensionless amplitude a_{0}≈2). The spectrum of the generated γ-ray beam is measured, with MeV resolution, seamlessly from 6 to 18 MeV, giving clear evidence of the onset of nonlinear relativistic Thomson scattering. To the best of our knowledge, this photon source has the highest peak brilliance in the multi-MeV regime ever reported in the literature.

Measurement of the muon reconstruction performance of the ATLAS detector using 2011 and 2012 LHC proton-proton collision data

This paper presents the performance of the ATLAS muon reconstruction during the LHC run with [Formula: see text] collisions at [Formula: see text]-8 TeV in 2011-2012, focusing mainly on data collected in 2012. Measurements of the reconstruction efficiency and of the momentum scale and resolution, based on large reference samples of [Formula: see text], [Formula: see text] and [Formula: see text] decays, are presented and compared to Monte Carlo simulations. Corrections to the simulation, to be used in physics analysis, are provided. Over most of the covered phase space (muon [Formula: see text] and [Formula: see text] GeV) the efficiency is above [Formula: see text] and is measured with per-mille precision. The momentum resolution ranges from [Formula: see text] at central rapidity and for transverse momentum [Formula: see text] GeV, to [Formula: see text] at large rapidity and [Formula: see text] GeV. The momentum scale is known with an uncertainty of [Formula: see text] to [Formula: see text] depending on rapidity. A method for the recovery of final state radiation from the muons is also presented.

Denis RD, Staerz S, Stahlman J, Stamen R, Stamm S, Stanecka E, Stanek RW, Stanescu C, Stanescu-Bellu M, Stanitzki MM, Stapnes S, Starchenko EA, Stark J, Staroba P, Starovoitov P, Staszewski R, Stavina P, Steinberg P, Stelzer B, Stelzer HJ, Stelzer-Chilton O, Stenzel H, Stern S, Stewart GA, Stillings JA, Stockton MC, Stoebe M, Stoicea G, Stolte P, Stonjek S, Stradling AR, Straessner A, Stramaglia ME, Strandberg J, Strandberg S, Strandlie A, Strauss E, Strauss M, Strizenec P, Ströhmer R, Strom DM, Stroynowski R, Stucci SA, Stugu B, Styles NA, Su D, Su J, Subramaniam R, Succurro A, Sugaya Y, Suhr C, Suk M, Sulin VV, Sultansoy S, Sumida T, Sun S, Sun X, Sundermann JE, Suruliz K, Susinno G, Sutton MR, Suzuki Y, Svatos M, Swedish S, Swiatlowski M, Sykora I, Sykora T, Ta D, Taccini C, Tackmann K, Taenzer J, Taffard A, Tafirout R, Taiblum N, Takai H, Takashima R, Takeda H, Takeshita T, Takubo Y, Talby M, Talyshev AA, Tam JYC, Tan KG, Tanaka J, Tanaka R, Tanaka S, Tanaka S, Tanasijczuk AJ, Tannenwald BB, Tannoury N, Tapprogge S, Tarem S, Tarrade F, Tartarelli GF, Tas P, Tasevsky M, Tashiro T, Tassi E, Tavares Delgado A, Tayalati Y, Taylor FE, Taylor GN, Taylor W, Teischinger FA, Teixeira Dias Castanheira M, Teixeira-Dias P, Temming KK, Ten Kate H, Teng PK, Teoh JJ, Terada S, Terashi K, Terron J, Terzo S, Testa M, Teuscher RJ, Therhaag J, Theveneaux-Pelzer T, Thomas JP, Thomas-Wilsker J, Thompson EN, Thompson PD, Thompson PD, Thompson RJ, Thompson AS, Thomsen LA, Thomson E, Thomson M, Thong WM, Thun RP, Tian F, Tibbetts MJ, Tikhomirov VO, Tikhonov YA, Timoshenko S, Tiouchichine E, Tipton P, Tisserant S, Todorov T, Todorova-Nova S, Toggerson B, Tojo J, Tokár S, Tokushuku K, Tollefson K, Tomlinson L, Tomoto M, Tompkins L, Toms K, Topilin ND, Torrence E, Torres H, Torró Pastor E, Toth J, Touchard F, Tovey DR, Tran HL, Trefzger T, Tremblet L, Tricoli A, Trigger IM, Trincaz-Duvoid S, Tripiana MF, Trischuk W, Trocmé B, Troncon C, Trottier-McDonald M, Trovatelli M, True P, Trzebinski M, Trzupek A, Tsarouchas C, Tseng JCL, Tsiareshka PV, Tsionou D, Tsipolitis G, Tsirintanis N, Tsiskaridze S, Tsiskaridze V, Tskhadadze EG, Tsukerman II, Tsulaia V, Tsuno S, Tsybychev D, Tudorache A, Tudorache V, Tuna AN, Tupputi SA, Turchikhin S, Turecek D, Turk Cakir I, Turra R, Tuts PM, Tykhonov A, Tylmad M, Tyndel M, Uchida K, Ueda I, Ueno R, Ughetto M, Ugland M, Uhlenbrock M, Ukegawa F, Unal G, Undrus A, Unel G, Ungaro FC, Unno Y, Unverdorben C, Urbaniec D, Urquijo P, Usai G, Usanova A, Vacavant L, Vacek V, Vachon B, Valencic N, Valentinetti S, Valero A, Valery L, Valkar S, Valladolid Gallego E, Vallecorsa S, Valls Ferrer JA, Van Den Wollenberg W, Van Der Deijl PC, van der Geer R, van der Graaf H, Van Der Leeuw R, van der Ster D, van Eldik N, van Gemmeren P, Van Nieuwkoop J, van Vulpen I, van Woerden MC, Vanadia M, Vandelli W, Vanguri R, Vaniachine A, Vankov P, Vannucci F, Vardanyan G, Vari R, Varnes EW, Varol T, Varouchas D, Vartapetian A, Varvell KE, Vazeille F, Vazquez Schroeder T, Veatch J, Veloso F, Veneziano S, Ventura A, Ventura D, Venturi M, Venturi N, Venturini A, Vercesi V, Verducci M, Verkerke W, Vermeulen JC, Vest A, Vetterli MC, Viazlo O, Vichou I, Vickey T, Vickey Boeriu OE, Viehhauser GHA, Viel S, Vigne R, Villa M, Villaplana Perez M, Vilucchi E, Vincter MG, Vinogradov VB, Virzi J, Vivarelli I, Vives Vaque F, Vlachos S, Vladoiu D, Vlasak M, Vogel A, Vogel M, Vokac P, Volpi G, Volpi M, von der Schmitt H, von Radziewski H, von Toerne E, Vorobel V, Vorobev K, Vos M, Voss R, Vossebeld JH, Vranjes N, Vranjes Milosavljevic M, Vrba V, Vreeswijk M, Vu Anh T, Vuillermet R, Vukotic I, Vykydal Z, Wagner P, Wagner W, Wahlberg H, Wahrmund S, Wakabayashi J, Walder J, Walker R, Walkowiak W, Wall R, Waller P, Walsh B, Wang C, Wang C, Wang F, Wang H, Wang H, Wang J, Wang J, Wang K, Wang R, Wang SM, Wang T, Wang X, Wanotayaroj C, Warburton A, Ward CP, Wardrope DR, Warsinsky M, Washbrook A, Wasicki C, Watkins PM, Watson AT, Watson IJ, Watson MF, Watts G, Watts S, Waugh BM, Webb S, Weber MS, Weber SW, Webster JS, Weidberg AR, Weigell P, Weinert B, Weingarten J, Weiser C, Weits H, Wells PS, Wenaus T, Wendland D, Weng Z, Wengler T, Wenig S, Wermes N, Werner M, Werner P, Wessels M, Wetter J, Whalen K, White A, White MJ, White R, White S, Whiteson D, Wicke D, Wickens FJ, Wiedenmann W, Wielers M, Wienemann P, Wiglesworth C, Wiik-Fuchs LAM, Wijeratne PA, Wildauer A, Wildt MA, Wilkens HG, Will JZ, Williams HH, Williams S, Willis C, Willocq S, Wilson A, Wilson JA, Wingerter-Seez I, Winklmeier F, Winter BT, Wittgen M, Wittig T, Wittkowski J, Wollstadt SJ, Wolter MW, Wolters H, Wosiek BK, Wotschack J, Woudstra MJ, Wozniak KW, Wright M, Wu M, Wu SL, Wu X, Wu Y, Wulf E, Wyatt TR, Wynne BM, Xella S, Xiao M, Xu D, Xu L, Yabsley B, Yacoob S, Yakabe R, Yamada M, Yamaguchi H, Yamaguchi Y, Yamamoto A, Yamamoto K, Yamamoto S, Yamamura T, Yamanaka T, Yamauchi K, Yamazaki Y, Yan Z, Yang H, Yang H, Yang UK, Yang Y, Yanush S, Yao L, Yao WM, Yasu Y, Yatsenko E, Yau Wong KH, Ye J, Ye S, Yeletskikh I, Yen AL, Yildirim E, Yilmaz M, Yoosoofmiya R, Yorita K, Yoshida R, Yoshihara K, Young C, Young CJS, Youssef S, Yu DR, Yu J, Yu JM, Yu J, Yuan L, Yurkewicz A, Yusuff I, Zabinski B, Zaidan R, Zaitsev AM, Zaman A, Zambito S, Zanello L, Zanzi D, Zeitnitz C, Zeman M, Zemla A, Zengel K, Zenin O, Ženiš T, Zerwas D, Zevi della Porta G, Zhang D, Zhang F, Zhang H, Zhang J, Zhang L, Zhang X, Zhang Z, Zhao Z, Zhemchugov A, Zhong J, Zhou B, Zhou L, Zhou N, Zhu CG, Zhu H, Zhu J, Zhu Y, Zhuang X, Zhukov K, Zibell A, Zieminska D, Zimine NI, Zimmermann C, Zimmermann R, Zimmermann S, Zimmermann S, Zinonos Z, Ziolkowski M, Zobernig G, Zoccoli A, zur Nedden M, Zurzolo G, Zutshi V, Zwalinski L. Measurement of flow harmonics with multi-particle cumulants in Pb+Pb collisions at [Formula: see text] TeV with the ATLAS detector

ATLAS measurements of the azimuthal anisotropy in lead-lead collisions at [Formula: see text] TeV are shown using a dataset of approximately 7 [Formula: see text]b[Formula: see text] collected at the LHC in 2010. The measurements are performed for charged particles with transverse momenta [Formula: see text] GeV and in the pseudorapidity range [Formula: see text]. The anisotropy is characterized by the Fourier coefficients, [Formula: see text], of the charged-particle azimuthal angle distribution for [Formula: see text]-4. The Fourier coefficients are evaluated using multi-particle cumulants calculated with the generating function method. Results on the transverse momentum, pseudorapidity and centrality dependence of the [Formula: see text] coefficients are presented. The elliptic flow, [Formula: see text], is obtained from the two-, four-, six- and eight-particle cumulants while higher-order coefficients, [Formula: see text] and [Formula: see text], are determined with two- and four-particle cumulants. Flow harmonics [Formula: see text] measured with four-particle cumulants are significantly reduced compared to the measurement involving two-particle cumulants. A comparison to [Formula: see text] measurements obtained using different analysis methods and previously reported by the LHC experiments is also shown. Results of measurements of flow fluctuations evaluated with multi-particle cumulants are shown as a function of transverse momentum and the collision centrality. Models of the initial spatial geometry and its fluctuations fail to describe the flow fluctuations measurements.

Blockade of the T cell immunoglobulin and mucin domain protein 3 pathway exacerbates sepsis-induced immune deviation and immunosuppression

Sepsis is a life-threatening condition, but the pathophysiological basis and biomarkers for the monitoring of sepsis and as targets for therapy remain to be determined. We have shown previously that T cell immunoglobulin and mucin domain protein 3 (Tim-3), a negative immune regulator, is involved in the physiopathology of sepsis, but the underlying mechanisms remain unclear. In the present study, we showed that Tim-3 signalling modulated the response patterns of both macrophages and T helper cells in sepsis. Blockade of the Tim-3 pathway exacerbated sepsis-induced proinflammatory macrophage responses and lymphocyte apoptosis during the early phase of sepsis, and enhanced the shift to anti-inflammatory responses for both macrophages and T helper cells during the late phase of sepsis. Tim-3 signalling was found to regulate CD80 and CD86 expression on macrophages both in vivo and in vitro. Co-culture of T cells with Tim-3 knock-down macrophages led to a biased T helper type 2 (Th2) response, partially explaining how Tim-3 signalling shapes inflammation patterns in vivo. Further studies on this pathway might shed new light on the pathogenesis of sepsis and suggest new approaches for intervention.

Observation of an excited Bc(±) meson state with the ATLAS detector

A search for excited states of the Bc(±) meson is performed using 4.9  fb(-1) of 7 TeV and 19.2  fb(-1) of 8 TeV pp collision data collected by the ATLAS experiment at the LHC. A new state is observed through its hadronic transition to the ground state, with the latter detected in the decay Bc(±)→J/ψπ(±). The state appears in the m(Bc(±)π(+)π(-))-m(Bc(±))-2m(π(±)) mass difference distribution with a significance of 5.2 standard deviations. The mass of the observed state is 6842±4±5  MeV, where the first error is statistical and the second is systematic. The mass and decay of this state are consistent with expectations for the second S-wave state of the Bc(±) meson, Bc(±)(2S).

Role of three commonly used scoring systems in prediction of pulmonary thromboembolism in Xining area

OBJECTIVE

To analyze the clinical values of three commonly used scoring systems including Wells score, revised Geneva score and Pisa score in predicting pulmonary thromboembolism (PTE) in Xining area.

PATIENTS AND METHODS

A total of 67 patients who had received CT pulmonary angiography (CTPA) in Qinghai Provincial People's Hospital from January 1, 2008 to July 31, 2010 due to suspected acute PTE were enrolled in this study. Among them 30 were confirmed to be with acute PTE and 37 were excluded. The risk of PTE was evaluated using the Wells score, the revised Geneva score, and Pisa score in all these patients. Clinical values of these scoring systems in diagnosis of PTE were compared using the receiver operating characteristic (ROC) curves; and CTPA values as the standard. The diagnostic accuracies were also compared.

RESULTS

The probability of PTE was 33.3% (14/42) when the Wells score was <2, 89.47% (17/19) when the Wells score was 2-6, and 100% (6/6) when the Wells score was above 6. The probability of PTE was 31.71% (13/40) when the revised Geneva score was 0-3, 85.0% (17/20) when the revised Geneva score was 4-10, and 100% (7/7) when the revised Geneva score was ≥11, suggesting that PTE might be associated with the revised Geneva score (p<0.001). When Pisa score was used, the probability of PTE was 20.59% (7/34), at ≥10%, 76.92% (10/13), at 10% to 90%, and 100% (20/20) at >90% score. The AUCs for all three scoring systems showed significant differences (p<0.05).

CONCLUSIONS

Thus, the Pisa score showed a relatively higher clinical value in Xining area to predict clinical probability of PTE in patients, with its overall sensitivity and specificity being higher than the Wells and revised Geneva score.

Optics design for J-TEXT ECE imaging with field curvature adjustment lens

Significant progress has been made in the imaging and visualization of magnetohydrodynamic and microturbulence phenomena in magnetic fusion plasmas. Of particular importance has been microwave electron cyclotron emission imaging (ECEI) for imaging Te fluctuations. Key to the success of ECEI is a large Gaussian optics system constituting a major portion of the focusing of the microwave radiation from the plasma to the detector array. Both the spatial resolution and observation range are dependent upon the imaging optics system performance. In particular, it is critical that the field curvature on the image plane is reduced to decrease crosstalk between vertical channels. The receiver optics systems for two ECEI on the J-TEXT device have been designed to ameliorate these problems and provide good performance with additional field curvature adjustment lenses with a meniscus shape to correct the aberrations from several spherical surfaces.