| 1. |
- Schael, S, et al.
(författare)
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Precision electroweak measurements on the Z resonance
- 2006
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Ingår i: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Forskningsöversikt (refereegranskat)abstract
- We report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. The data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLID experiment using a polarised beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarised asymmetries. The mass and width of the Z boson, m(Z) and Gamma(Z), and its couplings to fermions, for example the p parameter and the effective electroweak mixing angle for leptons, are precisely measured: m(Z) = 91.1875 +/- 0.0021 GeV, Gamma(Z) = 2.4952 +/- 0.0023 GeV, rho(l) = 1.0050 +/- 0.0010, sin(2)theta(eff)(lept) = 0.23153 +/- 0.00016. The number of light neutrino species is determined to be 2.9840 +/- 0.0082, in agreement with the three observed generations of fundamental fermions. The results are compared to the predictions of the Standard Model (SM). At the Z-pole, electroweak radiative corrections beyond the running of the QED and QCD coupling constants are observed with a significance of five standard deviations, and in agreement with the Standard Model. Of the many Z-pole measurements, the forward-backward asymmetry in b-quark production shows the largest difference with respect to its SM expectation, at the level of 2.8 standard deviations. Through radiative corrections evaluated in the framework of the Standard Model, the Z-pole data are also used to predict the mass of the top quark, m(t) = 173(+10)(+13) GeV, and the mass of the W boson, m(W) = 80.363 +/- 0.032 GeV. These indirect constraints are compared to the direct measurements, providing a stringent test of the SM. Using in addition the direct measurements of m(t) and m(W), the mass of the as yet unobserved SM Higgs boson is predicted with a relative uncertainty of about 50% and found to be less than 285 GeV at 95% confidence level. (c) 2006 Elsevier B.V. All rights reserved.
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| 2. |
- Aamodt, K., et al.
(författare)
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The ALICE experiment at the CERN LHC
- 2008
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Ingår i: Journal of Instrumentation. - 1748-0221. ; 3:S08002
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Forskningsöversikt (refereegranskat)abstract
- ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC which focuses on QCD, the strong-interaction sector of the Standard Model. It is designed to address the physics of strongly interacting matter and the quark-gluon plasma at extreme values of energy density and temperature in nucleus-nucleus collisions. Besides running with Pb ions, the physics programme includes collisions with lighter ions, lower energy running and dedicated proton-nucleus runs. ALICE will also take data with proton beams at the top LHC energy to collect reference data for the heavy-ion programme and to address several QCD topics for which ALICE is complementary to the other LHC detectors. The ALICE detector has been built by a collaboration including currently over 1000 physicists and engineers from 105 Institutes in 30 countries, Its overall dimensions are 16 x 16 x 26 m(3) with a total weight of approximately 10 000 t. The experiment consists of 18 different detector systems each with its own specific technology choice and design constraints, driven both by the physics requirements and the experimental conditions expected at LHC. The most stringent design constraint is to cope with the extreme particle multiplicity anticipated in central Pb-Pb collisions. The different subsystems were optimized to provide high-momentum resolution as well as excellent Particle Identification (PID) over a broad range in momentum, up to the highest multiplicities predicted for LHC. This will allow for comprehensive studies of hadrons, electrons, muons, and photons produced in the collision of heavy nuclei. Most detector systems are scheduled to be installed and ready for data taking by mid-2008 when the LHC is scheduled to start operation, with the exception of parts of the Photon Spectrometer (PHOS), Transition Radiation Detector (TRD) and Electro Magnetic Calorimeter (EMCal). These detectors will be completed for the high-luminosity ion run expected in 2010. This paper describes in detail the detector components as installed for the first data taking in the summer of 2008.
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| 3. |
- Abazov, V. M., et al.
(författare)
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The upgraded DO detector
- 2006
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 565:2, s. 463-537
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Tidskriftsartikel (refereegranskat)abstract
- The DO experiment enjoyed a very successful data-collection run at the Fermilab Tevatron collider between 1992 and 1996. Since then, the detector has been upgraded to take advantage of improvements to the Tevatron and to enhance its physics capabilities. We describe the new elements of the detector, including the silicon microstrip tracker, central fiber tracker, solenoidal magnet, preshower detectors, forward muon detector, and forward proton detector. The uranium/liquid -argon calorimeters and central muon detector, remaining from Run 1, are discussed briefly. We also present the associated electronics, triggering, and data acquisition systems, along with the design and implementation of software specific to DO.
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| 4. |
- Ablikim, M., et al.
(författare)
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Measurements of (XcJ)-> K+K-K+K- decays
- 2006
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 642:3, s. 197-202
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Tidskriftsartikel (refereegranskat)abstract
- Using 14M psi(2S) events taken with the BESII detector, chi(cJ) -> 2(K+K-) decays are studied. For the four-kaon final state, the branching fractions are B(chi(c0,1,2) ->.2(K+K-)) = (3.48 +/- 0.23 +/- 0.47) x 10(-3), (0.70 +/- 0.13 +/- 0.10) x 10(-3), and (2.17 +/- 0.20 +/- 0.31) x 10(-3). For the phi K+K- final state, the branching fractions, which are measured for the first time, are B(chi(c0,1,2) -> phi K+K-) = (1.03 +/- 0.22 +/- 0.15) x 10(-3), (0.46 +/- 0.16 +/- 0.06) x 10(-3), and (1.67 +/- 0.26 +/- 0.24) x 10(-4). For the phi phi final state, B(chi(c0,2) -> phi phi) = (0.94 +/- 0.21 +/- 0.13) x 10(-3) and (1.70 +/- 0.30 +/- 0.25) x 10(-3).
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| 5. |
- Lu, R, et al.
(författare)
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Genetic associations of LYN with systemic lupus erythematosus
- 2009
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Ingår i: Genes and Immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 10:5, s. 397-403
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Tidskriftsartikel (refereegranskat)abstract
- We targeted LYN, a src-tyosine kinase involved in B-cell activation, in case-control association studies using populations of European-American, African-American and Korean subjects. Our combined European-derived population, consisting of 2463 independent cases and 3131 unrelated controls, shows significant association with rs6983130 in a female-only analysis with 2254 cases and 2228 controls (P=1.1 x 10(-4), odds ratio (OR)=0.81 (95% confidence interval: 0.73-0.90)). This single nucleotide polymorphism (SNP) is located in the 5' untranslated region within the first intron near the transcription initiation site of LYN. In addition, SNPs upstream of the first exon also show weak and sporadic association in subsets of the total European-American population. Multivariate logistic regression analysis implicates rs6983130 as a protective factor for systemic lupus erythematosus (SLE) susceptibility when anti-dsDNA, anti-chromatin, anti-52 kDa Ro or anti-Sm autoantibody status were used as covariates. Subset analysis of the European-American female cases by American College of Rheumatology classification criteria shows a reduction in the risk of hematological disorder with rs6983130 compared with cases without hematological disorders (P=1.5 x 10(-3), OR=0.75 (95% CI: 0.62-0.89)). None of the 90 SNPs tested show significant association with SLE in the African American or Korean populations. These results support an association of LYN with European-derived individuals with SLE, especially within autoantibody or clinical subsets.
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| 6. |
- McMahon, J J, et al.
(författare)
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CMP compatibility of partially cured benzocyclobutene (BCB) for a via-first 3D IC process
- 2005
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Ingår i: Chemical-Mechanical Planarization-Integration, Technology and Reliability. - WARRENDALE, PA : MATERIALS RESEARCH SOCIETY. - 1558998209 ; , s. 63-68
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Konferensbidrag (refereegranskat)abstract
- Wafer-level three dimensional (3D) IC technology offers the promise of decreasing RC delays by reducing long interconnect lines in high performance ICs. This paper focuses on a via-first 3D IC platform, which utilizes a back-end-of-line (BEOL) compatible damascene-patterned layer of copper and Benzocyclobutene (BCB). This damascene-patterned copper/BCB serves as a redistribution layer between two fully fabricated wafer sets of ICs and offers the potential of high bonding strength and low contact resistance for inter-wafer interconnects between the wafer pair. The process would thus combine the electrical advantages of 3D technology using Cu-to-Cu bonding with the mechanical advantages of 3D technology using BCB-to-BCB bonding. In this work, partially cured BCB has been evaluated for copper damascene patterning using commercially available CMP slurries as a key process step for a via-first 3D process flow. BCB is spin-cast on 200 mm wafers and cured at temperatures ranging from 190 degrees C to 250 degrees C, providing a wide range of crosslink percentage. These films are evaluated for CMP removal rate, surface damage (surface scratching and embedded abrasives), and planarity with commercially available copper CMP slurries. Under baseline process parameters, erosion, and roughness changes are presented for single-level damascene test patterns. After wafers are bonded under controlled temperature and pressure, the bonding interface is inspected optically using glass-to-silicon bonded wafers, and the bond strength is evaluated by a razor blade test.
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| 7. |
- McMahon, J J, et al.
(författare)
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Unit processes for Cu/BCB redistribution layer bonding for 3D ICs
- 2006
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Ingår i: Advanced Metallization Conference 2005 (AMC 2005). - WARRENDALE : MATERIALS RESEARCH SOCIETY. - 1558998659 ; , s. 179-183
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Konferensbidrag (refereegranskat)abstract
- A novel via-first, back-end-of-the-line (BEOL) compatible, monolithic wafer-level three-dimensional (3D) interconnect technology platform is presented. This platform employs wafer bonding of damascene-patterned metal/adhesive redistribution layers on two wafers to provide both high density of inter-wafer electrical interconnects and strong adhesive bond of two wafers in a single unit processing step. Two key steps for this approach are 1) fabrication of a metal/adhesive redistribution layer on the BEOLprocessed wafers by damascene patterning and 2) face-to-face alignment and bonding of two wafers utilizing copper/tantalum (Cu/Ta) and benzocyclobutene (BCB) redistribution layers. A baseline process and two modified processes are investigated toward evaluation of 1) acceptable wafer-scale nonplanarity, removal rate, and surface damage after CMP and 2) seamless bonding at all three possible interfaces with sufficiently strong BCB-to-BCB critical adhesion energy and Cu-to-Cu contact resistance. Migration of voids in the sputtered copper during bonding and etch profiles for different etch processes are discussed.
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| 8. |
- Niklaus, Frank, et al.
(författare)
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Adhesive wafer bonding using partially cured benzocyclobutene for three-dimensional integration
- 2006
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Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 153:4, s. G291-G295
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Tidskriftsartikel (refereegranskat)abstract
- Wafer-level three-dimensional integration (3D) is an emerging technology to increase the performance and functionality of integrated circuits (ICs), with adhesive wafer bonding a key step in one of the attractive technology platforms. In such an application, the dielectric adhesive layer needs to be very uniform, and precise wafer-to-wafer alignment accuracy (similar to 1 mu m) of the bonded wafers is required. In this paper we present a new adhesive wafer bonding process that involves partially curing (cross-linking) of the benzocyclobutene (BCB) coatings prior to bonding. The partially cured BCB layer essentially does not reflow during bonding, minimizing the impact of inhomogeneities in BCB reflow under compression and/or any shear forces at the bonding interface. The resultant nonuniformity of the BCB layer thickness after wafer bonding is less than 1% of the average layer thickness, and the wafers shift relative to each other during the wafer bonding process less than 1 mu m (average) for 200 mm diameter wafers. When bonding two silicon wafers using partially cured BCB, the critical adhesion energy is sufficiently high (>= 14 J/m(2)) for subsequent IC processing.
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| 9. |
- Niklaus, Frank, et al.
(författare)
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Effects of bonding process parameters on wafer-to-wafer alignment accuracy in benzocyclobutene (BCB) dielectric wafer bonding
- 2005
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Ingår i: Materials, Technology and Reliability of Advanced Interconnects-2005. - WARRENDALE, PA : MATERIALS RESEARCH SOCIETY. - 1558998160 ; , s. 393-398
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Konferensbidrag (refereegranskat)abstract
- Wafer-level three-dimensional (3D) integration is an emerging technology to increase the performance and functionality of integrated circuits (ICs). Aligned wafer-to-wafer bonding with dielectric polymer layers (e.g., benzocyclobutene (BCB)) is a promising approach for manufacturing of 3D ICs, with minimum bonding impact on the wafer-to-wafer alignment accuracy essential. In this paper we investigate the effects of thermal and mechanical bonding parameters on the achievable post-bonding wafer-to-wafer alignment accuracy for polymer wafer bonding with 200 trim diameter wafers. Our baseline wafer bonding process with soft-baked BCB (similar to 35% cross-linked) has been modified to use partially cured (similar to 43% crosslinked) BCB. The partially cured BCB layer does not reflow during bonding, minimizing the impact of inhomogeneities in BCB reflow under compression and/or slight shear forces at the bonding interface. As a result, the non-uniformity of the BCB layer thickness after wafer bonding is less than 0.5% of the nominal layer thickness and the wafer shift relative to each other during the wafer bonding process is less than 1 mu m (average) for 200 mm diameter wafers. The critical adhesion energy of a bonded wafer pair with the partially cured BCB wafer bonding process is similar to that with soft-baked BCB.
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| 10. |
- Niklaus, Frank, et al.
(författare)
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Wafer-Level 3D Integration Technology Platforms for ICs and MEMS
- 2005
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Ingår i: TWENTY SECOND INTERNATIONAL VLSI MULTILEVEL INTERCONNECTION (VMIC). ; , s. 486-493
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Wafer-level three-dimensional (3D) integration is an emerging technology to increase theperformance and functionality of integrated circuits (ICs) and microelectromechanical systems(MEMS). In ICs, wafer-level 3D integration based on wafer bonding offers the potential for a highdensity of micron-sized through-die vias necessary for highest performance memory stacks,microprocessors with large L2 caches and ASICs with large embedded memories. In MEMS devices,wafer-level 3D integration based on wafer bonding offers the potential for integrating highperformance transducer materials such as various monocrystalline semiconductor materials withelectronic circuits for arrayed, highly integrated sensor and actuator components. This invited paperpresents an overview of current wafer-level 3D integration platforms that use wafer bonding withpolymer adhesives for ICs and MEMS applications.
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| 11. |
- Gutmann, R.J., et al.
(författare)
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Wafer-Level Via-First 3D Integration with Hybrid-Bonding of Cu/BCB Redistribution Layers
- 2005
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Three-dimensional (3D) integration with through-die viasoffer improved electrical performance compared to edgeconnectedwire bonds in stacked-die assemblies for wirelessapplications. Monolithic wafer-level 3D integration offersthe potential for a high density of micron-sized through-dievias necessary for highest performance memory stacks,microprocessors with large L2 caches and ASICs with largeembedded memories. In addition, such wafer-leveltechnologies offer the potential of lowest cost in largemanufacturing volume of any heterogeneous integrationplatform, incorporating the inherent low cost of monolithicIC interconnectivity. After a brief summary of current wafer-level 3D integrationplatforms, a recently introduced platform that offers theprocess integration advantage of copper-to-copper (Cu-to-Cu) bonding with the increased adhesion strength andenvironmental robustness of dielectric adhesive bondingusing benzocyclobutene (BCB) is discussed. Criticalprocessing challenges of the new platform include BCBpartial curing compatible with damascene patterning, postdamascene-patterning cleaning and surface activation,bonding process parameters, and wafer-level planarizationrequirements. The inherent incorporation of a redistributionlayer into the bonding layer process further reduces theprocess flow and is compatible with wafer-level packaging(WLP) technologies.
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| 12. |
- Lee, Sang Hwui, et al.
(författare)
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Fine keyed alignment and bonding for wafer-level 3D ICs
- 2006
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Ingår i: MATERIALS RESEARCH SOCIETY SYMPOSIUM PROCEEDINGS. - WARRENDALE, PA : MATERIALS RESEARCH SOCIETY. ; , s. 433-438
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Konferensbidrag (refereegranskat)abstract
- Precise wafer-to-wafer alignment accuracy is crucial to interconnecting circuits on different wafers in three dimensional integrated circuits. We discuss the use of fabricated structures on wafer surfaces to mechanically achieve higher alignment accuracy than can be achieved with our existing (baseline) alignment protocol. The keyed alignment structures rely on structures with tapered side-walls that can slide into each after two wafers are "pre-aligned" using our baseline alignment protocol. Results indicate that alignment accuracy is about a quarter micron, well below the one micron alignment accuracy obtained in our baseline alignment procedure using commercial state-of-the-art wafer alignment equipment. In addition to improving alignment, the alignment structures also hinder undesirable bonding-induced misalignment. The keyed alignment structures are also promising for nano-imprint lithography.
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| 13. |
- Hu, Q.M., et al.
(författare)
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Effect of Zr on the properties of (TiZr)Ni alloys from first-principles calculations
- 2007
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Ingår i: Physical Review B. - 0163-1829. ; 76:22, s. 224201-
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Tidskriftsartikel (refereegranskat)abstract
- The effect of Zr on the martensitic transformation (MT) behavior and mechanical properties of (Ti(0.5-x)Zr(x))Ni(0.5) alloys is investigated by calculating the elastic constants and elastic moduli in the B2 phase as a function of x for 0 <= x <= 0.2. The calculations are performed using the coherent potential approximation implemented within the framework of the exact muffin-tin orbitals method. We find that the theoretical elastic properties correlate well with the behavior of the MT. With increasing Zr concentration, the anisotropy of the alloy decreases, indicating that the nonbasal plane shear on which the modulus C(44) plays an important role, dominates and, therefore, a monoclinic martensitic phase should result. The experimental Zr content dependence of the MT temperature is paralleled with the calculated C(44) versus Zr content. The theoretical elastic moduli demonstrate that the (TiZr)Ni alloys, with Zr distributed randomly on the Ti sublattice, are intrinsically ductile, which suggests that the poor ductility of these alloys may be ascribed to some other factors, for example, impurities, precipitation, and grain boundaries.
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| 14. |
- Niklaus, Frank, et al.
(författare)
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Adhesive wafer bonding
- 2006
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 99:3
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Forskningsöversikt (refereegranskat)abstract
- Wafer bonding with intermediate polymer adhesives is an important fabrication technique for advanced microelectronic and microelectromechanical systems, such as three-dimensional integrated circuits, advanced packaging, and microfluidics. In adhesive wafer bonding, the polymer adhesive bears the forces involved to hold the surfaces together. The main advantages of adhesive wafer bonding include the insensitivity to surface topography, the low bonding temperatures, the compatibility with standard integrated circuit wafer processing, and the ability to join different types of wafers. Compared to alternative wafer bonding techniques, adhesive wafer bonding is simple, robust, and low cost. This article reviews the state-of-the-art polymer adhesive wafer bonding technologies, materials, and applications.
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| 15. |
- Lu, Q, et al.
(författare)
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No difference in nitrogen balance between standard prescriptions of hemodialysis and peritoneal dialysis
- 2008
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Ingår i: Blood purification. - : S. Karger AG. - 1421-9735 .- 0253-5068. ; 26:6, s. 511-517
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Tidskriftsartikel (refereegranskat)abstract
- <i>Background:</i> It has been thought that peritoneal dialysis (PD) may not achieve adequate solute removal after the loss of residual renal function when compared to hemodialysis (HD). However, it should be noted that adequate solute removal depends not only on dialysis dose but also on dietary intake. Therefore, in the present study, we compared, both theoretically and clinically, the dietary protein intake and nitrogen removal between standard HD and PD as currently practiced in China. <i>Methods:</i> The nitrogen removal for both HD and PD was calculated theoretically with defined membrane permeability. For HD, the urea removal was based on a 2-compartment model. We compared the dietary protein intake and the amount of nitrogen removed at dialysis in 38 anuric well-nourished hemodialysis patients and 44 peritoneal dialysis patients. <i>Results:</i> With the theoretical calculation, setting the blood urea level at 21 or 26 mmol/l for both dialysis modalities, with the current practice pattern (4 exchanges of 2 liters of dialysis solution a day for PD and 4 h × 3 per week for HD), HD and PD removed almost identical amounts of nitrogen, and the allowable dietary protein intakes to achieve nitrogen balance for each modality were about 0.9 and 1.0 g/kg/day, respectively. In the 38 HD patients, the peak blood urea concentration was 26.44 ± 3.96 mmol/l, significantly higher than that of PD patients (20.85 ± 4.08 mmol/l). There was no significant difference in the dietary protein intake between the 2 modalities: 1.01 ± 0.29 and 0.91 ± 0.28 g/kg/day for HD patients and PD patients, respectively. <i>Conclusions:</i> Our study suggests that to achieve the same level of blood urea level, the protein intake and nitrogen removal is almost identical between HD and PD with the current practice pattern, indicating PD could provide similar dialysis adequacy to that of HD when patients lose their residual renal function.
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| 16. |
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| 17. |
- Qiu, X. Y., et al.
(författare)
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Room-temperature weak ferromagnetism of amorphous HfAlOx thin films deposited by pulsed laser deposition
- 2006
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Ingår i: Applied Physics Letters. - : American Institute of Physics (AIP). - 0003-6951 .- 1077-3118. ; 89:24, s. 242504-
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Tidskriftsartikel (refereegranskat)abstract
- The room-temperature weak ferromagnetism of amorphous HfAlOx thin films deposited by pulsed laser deposition on various substrates in oxygen-defective ambient is demonstrated. The magnetization is independent of film thickness, but depends on substrates and deposition temperatures. A magnetic moment of similar to 0.26 mu(B) per HfAlOx f.u. is recorded for HfAlOx films deposited under optimized conditions [deposited at 600 degrees C on (001) sapphire in high vacuum]. It is argued that interfacial defects are one of the possible sources of the weak ferromagnetism. (c) 2006 American Institute of Physics.
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| 18. |
- Zhao, Zhi, et al.
(författare)
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Experimental realization of optimal asymmetric cloning and telecloning via partial teleportation
- 2005
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Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 95:3, s. 030502-
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Tidskriftsartikel (refereegranskat)abstract
- We report an experimental realization of both optimal asymmetric cloning and telecloning of single photons by making use of partial teleportation of an unknown state. In the experiment, we demonstrate that, conditioned on the success of partial teleportation of single photons, not only the optimal asymmetric cloning can be accomplished, but also one of two outputs can be transferred to a distant location, realizing the telecloning. The experimental results represent a novel way to achieve quantum cloning and may have potential applications in the context of quantum communication.
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