| 1. |
- Aad, G, et al.
(author)
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- 2015
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swepub:Mat__t
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| 2. |
- Schael, S., et al.
(author)
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Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
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Research review (peer-reviewed)abstract
- Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
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| 3. |
- Schael, S, et al.
(author)
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Precision electroweak measurements on the Z resonance
- 2006
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In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 427:5-6, s. 257-454
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Research review (peer-reviewed)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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| 4. |
- Cung, T. -T., et al.
(author)
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Cyclosporine before PCI in Patients with Acute Myocardial Infarction
- 2015
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In: New England Journal of Medicine. - 0028-4793. ; 373:11, s. 1021-1031
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Journal article (peer-reviewed)abstract
- BACKGROUND Experimental and clinical evidence suggests that cyclosporine may attenuate reperfusion injury and reduce myocardial infarct size. We aimed to test whether cyclosporine would improve clinical outcomes and prevent adverse left ventricular remodeling. METHODS In a multicenter, double-blind, randomized trial, we assigned 970 patients with an acute anterior ST-segment elevation myocardial infarction (STEMI) who were undergoing percutaneous coronary intervention (PCI) within 12 hours after symptom onset and who had complete occlusion of the culprit coronary artery to receive a bolus injection of cyclosporine (administered intravenously at a dose of 2.5 mg per kilogram of body weight) or matching placebo before coronary recanalization. The primary outcome was a composite of death from any cause, worsening of heart failure during the initial hospitalization, rehospitalization for heart failure, or adverse left ventricular remodeling at 1 year. Adverse left ventricular remodeling was defined as an increase of 15% or more in the left ventricular end-diastolic volume. RESULTS A total of 395 patients in the cyclosporine group and 396 in the placebo group received the assigned study drug and had data that could be evaluated for the primary outcome at 1 year. The rate of the primary outcome was 59.0% in the cyclosporine group and 58.1% in the control group (odds ratio, 1.04; 95% confidence interval, 0.78 to 1.39; P = 0.77). Cyclosporine did not reduce the incidence of the separate clinical components of the primary outcome or other events, including recurrent infarction, unstable angina, and stroke. No significant difference in the safety profile was observed between the two treatment groups. CONCLUSIONS In patients with anterior STEMI who had been referred for primary PCI, intravenous cyclosporine did not result in better clinical outcomes than those with placebo and did not prevent adverse left ventricular remodeling at 1 year. (Funded by the French Ministry of Health and NeuroVive Pharmaceutical; CIRCUS ClinicalTrials.gov number, NCT01502774; EudraCT number, 2009-013713-99.)
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| 5. |
- Andreoni, I., et al.
(author)
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Follow Up of GW170817 and Its Electromagnetic Counterpart by Australian-Led Observing Programmes
- 2017
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In: Publications Astronomical Society of Australia. - : Cambridge University Press (CUP). - 1323-3580 .- 1448-6083. ; 34
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Research review (peer-reviewed)abstract
- The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (similar to 2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
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| 6. |
- Adami, C., et al.
(author)
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The XXL Survey: XX. The 365 cluster catalogue
- 2018
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In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 620
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Journal article (peer-reviewed)abstract
- Context. In the currently debated context of using clusters of galaxies as cosmological probes, the need for well-defined cluster samples is critical. Aims. The XXL Survey has been specifically designed to provide a well characterised sample of some 500 X-ray detected clusters suitable for cosmological studies. The main goal of present article is to make public and describe the properties of the cluster catalogue in its present state, as well as of associated catalogues of more specific objects such as super-clusters and fossil groups. Methods. Following from the publication of the hundred brightest XXL clusters, we now release a sample containing 365 clusters in total, down to a flux of a few 10-15 erg s-1 cm-2 in the [0.5-2] keV band and in a 1′ aperture. This release contains the complete subset of clusters for which the selection function is well determined plus all X-ray clusters which are, to date, spectroscopically confirmed. In this paper, we give the details of the follow-up observations and explain the procedure adopted to validate the cluster spectroscopic redshifts. Considering the whole XXL cluster sample, we have provided two types of selection, both complete in a particular sense: one based on flux-morphology criteria, and an alternative based on the [0.5-2] keV flux within 1 arcmin of the cluster centre. We have also provided X-ray temperature measurements for 80% of the clusters having a flux larger than 9 × 10-15 erg s-1 cm-2. Results. Our cluster sample extends from z ∼ 0 to z ∼ 1.2, with one cluster at z ∼ 2. Clusters were identified through a mean number of six spectroscopically confirmed cluster members. The largest number of confirmed spectroscopic members in a cluster is 41. Our updated luminosity function and luminosity-temperature relation are compatible with our previous determinations based on the 100 brightest clusters, but show smaller uncertainties. We also present an enlarged list of super-clusters and a sample of 18 possible fossil groups. Conclusions. This intermediate publication is the last before the final release of the complete XXL cluster catalogue when the ongoing C2 cluster spectroscopic follow-up is complete. It provides a unique inventory of medium-mass clusters over a 50 deg2 area out to z ∼ 1.
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| 7. |
- Needham, E. J., et al.
(author)
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Brain injury in COVID-19 is associated with dysregulated innate and adaptive immune responses
- 2022
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In: Brain. - : Oxford University Press (OUP). - 0006-8950 .- 1460-2156. ; 145:11, s. 4097-4107
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Journal article (peer-reviewed)abstract
- COVID-19 is associated with neurological complications including stroke, delirium and encephalitis. Furthermore, a post-viral syndrome dominated by neuropsychiatric symptoms is common, and is seemingly unrelated to COVID-19 severity. The true frequency and underlying mechanisms of neurological injury are unknown, but exaggerated host inflammatory responses appear to be a key driver of COVID-19 severity. We investigated the dynamics of, and relationship between, serum markers of brain injury [neurofilament light (NfL), glial fibrillary acidic protein (GFAP) and total tau] and markers of dysregulated host response (autoantibody production and cytokine profiles) in 175 patients admitted with COVID-19 and 45 patients with influenza. During hospitalization, sera from patients with COVID-19 demonstrated elevations of NfL and GFAP in a severity-dependent manner, with evidence of ongoing active brain injury at follow-up 4 months later. These biomarkers were associated with elevations of pro-inflammatory cytokines and the presence of autoantibodies to a large number of different antigens. Autoantibodies were commonly seen against lung surfactant proteins but also brain proteins such as myelin associated glycoprotein. Commensurate findings were seen in the influenza cohort. A distinct process characterized by elevation of serum total tau was seen in patients at follow-up, which appeared to be independent of initial disease severity and was not associated with dysregulated immune responses unlike NfL and GFAP. These results demonstrate that brain injury is a common consequence of both COVID-19 and influenza, and is therefore likely to be a feature of severe viral infection more broadly. The brain injury occurs in the context of dysregulation of both innate and adaptive immune responses, with no single pathogenic mechanism clearly responsible. Needham et al. reveal elevations in blood biomarkers of brain injury in patients hospitalised with COVID-19. The changes, which were severity-dependent, were associated with dysregulated immune responses including increases in pro-inflammatory cytokines and autoantibodies. Ongoing active brain injury could still be seen months after infection.
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| 8. |
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| 9. |
- Uchino, H, et al.
(author)
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Amelioration by cyclosporin A of brain damage in transient forebrain ischemia in the rat
- 1998
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In: Brain Research. - 1872-6240. ; 812:1-2, s. 216-226
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Journal article (peer-reviewed)abstract
- The immunosuppressant drug cyclosporin A (CsA) is considered to be inherently protective in conditions of ischemia, e.g. in hepatic and cardiac tissue. However, investigations of effects of CsA on neuronal tissue have been contradictory, probably because the blood-brain barrier (BBB) is virtually impermeable to CsA. In the present study, we exploited the finding that the insertion of a syringe needle into brain parenchyma obviously disrupts the BBB and allows influx of CsA, and explored whether CsA, given as intraperitoneal injections daily for 1 week before and 1 week after forebrain ischemia of 7 or 10 min duration, ameliorates the damage incurred to the hippocampal CA 1 sector. In other experiments, the needle insertion and the first i.p. injection of CsA were made 30 min after the start of recirculation, with continued daily administration of CsA during the postinsult week. In animals which were injected with CsA in daily doses of 10 mg kg-1, but in which no needle was inserted, the drug failed to ameliorate CA1 damage, whether the ischemia had a duration of 7 or 10 min. Likewise, needle insertion had no effect on CA1 damage if CsA was not administered. In contrast, when CsA was given to animals with a needle insertion, CA1 damage was dramatically ameliorated, whether treatment was initiated 1 week before ischemia, or 30 min after the start of recirculation. The effect of CsA seemed larger than that of any other drug proposed to have an anti-ischemic effect in forebrain/global ischemia. Injection of tritiated CsA in one animal with BBB disruption lead to detectable radioactivity throughout the ventricular system, suggesting a generalised increase of the entry of CsA across the BBB. The results demonstrate that immunosuppressants of the type represented by CsA markedly ameliorate delayed neuronal damage after transient forebrain ischemia, provided that they can pass the BBB. It is discussed whether the effect of the drug is one involving calcineurin, a protein phosphatase, or if CsA counteracts a permeability transition of the inner mitochondrial membrane, assumed to occur in response to adverse conditions, e.g. gradual accumulation of Ca2+ in the mitochondria in the postischemic period.
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| 10. |
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| 11. |
- Elmer, R, et al.
(author)
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K+ emission in symmetric heavy ion reactions at subthreshold energies
- 1996
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In: PHYSICAL REVIEW LETTERS. - : AMER INST PHYSICS. ; 77:24, s. 4884-4886
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Journal article (peer-reviewed)abstract
- Subthreshold K+ production cross sections have been measured in symmetric Ne + NaF, Ni + Ni, and Au + Au collisions at 1.0A GeV. The mass dependence is strong, close to A(2). The angular distributions are nonisotropic in the center-of-mass system. Introdu
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| 12. |
- Elmer, Steven, et al.
(author)
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Improvements in multi-joint leg function following chronic eccentric exercise
- 2012
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In: Scandinavian Journal of Medicine and Science in Sports. - : Wiley. - 0905-7188 .- 1600-0838. ; 22:5, s. 653-661
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Journal article (peer-reviewed)abstract
- Previous authors have reported that chronic eccentric cycling facilitates greater changes in multi-joint leg function (hopping frequency, maximum jumping height) compared with concentric cycling. Our purpose was to evaluate changes in leg spring stiffness and maximum power following eccentric and concentric cycling training. Twelve individuals performed either eccentric (n=6) or concentric (n=6) cycling for 7 weeks (3 sessions/week) while training duration progressively increased. Participants performed trials of submaximal hopping, maximal counter movement jumps, and maximal concentric cycling to evaluate leg spring stiffness, maximum jumping power, and maximum concentric cycling power respectively, before and 1 week following training. Total work during training did not differ between eccentric and concentric cycling (126 ± 15–728 ± 91 kJ vs 125 ± 10–787 ± 76 kJ). Following training, eccentric cycling exhibited greater changes in kleg and jumping Pmax compared with CONcyc (10 ± 3% vs −2 ± 4% and 7 ± 2% vs −2 ± 3%, respectively, P=0.05). Alterations in CONcycPmax did not differ between ECCcyc (1035 ± 142 vs 1030 ± 133 W) and CONcyc (1072 ± 98 vs 1081 ± 85 W). These data demonstrate that eccentric cycling is an effective method for improving leg spring stiffness and maximum power during multi-joint tasks that include stretch-shortening cycles. Improvements in leg spring stiffness and maximum power would be beneficial for both aging and athletic populations.
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| 13. |
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| 14. |
- Junker, Alex, et al.
(author)
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Human studies of mitochondrial biology demonstrate an overall lack of binary sex differences : A multivariate meta-analysis
- 2022
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In: FASEB Journal. - 0892-6638. ; 36:2
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Journal article (peer-reviewed)abstract
- Mitochondria are maternally inherited organelles that play critical tissue-specific roles, including hormone synthesis and energy production, that influence human development, health, and aging. However, whether mitochondria from women and men exhibit consistent biological differences remains unclear, representing a major gap in knowledge. This meta-analysis systematically examined four domains and six subdomains of mitochondrial biology (total 39 measures), including mitochondrial content, respiratory capacity, reactive oxygen species (ROS) production, morphometry, and mitochondrial DNA copy number. Standardized effect sizes (Hedge's g) of sex differences were computed for each measure using data in 2258 participants (51.5% women) from 50 studies. Only two measures demonstrated aggregate binary sex differences: higher mitochondrial content in women's WAT and isolated leukocyte subpopulations (g = 0.20, χ2 p =.01), and higher ROS production in men's skeletal muscle (g = 0.49, χ2 p <.0001). Sex differences showed weak to no correlation with age or BMI. Studies with small sample sizes tended to overestimate effect sizes (r = −.17, p <.001), and sex differences varied by tissue examined. Our findings point to a wide variability of findings in the literature concerning possible binary sex differences in mitochondrial biology. Studies specifically designed to capture sex- and gender-related differences in mitochondrial biology are needed, including detailed considerations of physical activity and sex hormones.
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| 15. |
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| 16. |
- Mewton, Nathan, et al.
(author)
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Rationale and design of the Cyclosporine to ImpRove Clinical oUtcome in ST-elevation myocardial infarction patients (the CIRCUS trial)
- 2015
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In: American Heart Journal. - : Elsevier BV. - 1097-6744 .- 0002-8703. ; 169:6, s. 6-766
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Journal article (peer-reviewed)abstract
- Background Both acute myocardial ischemia and reperfusion contribute to cardiomyocyte death in ST-elevation myocardial infarction (STEMI). The final infarct size is the principal determinant of subsequent clinical outcome in STEMI patients. In a proof-of-concept phase II trial, the administration of cyclosporine prior to primary percutaneous coronary intervention (PPCI) has been associated with a reduction of infarct size in STEMI patients. Methods CIRCUS is an international, prospective, multicenter, randomized, double-blinded, placebo-controlled trial. The study is designed to compare the efficacy and safety of cyclosporine versus placebo, in addition to revascularization by PPCI, in patients presenting with acute anterior myocardial infarction within 12 hours of symptoms onset and initial TIMI flow <= 1 in the culprit left anterior descending coronary artery. Patients are randomized in a 1: 1 fashion to 2.5 mg/kg intravenous infusion of cyclosporine or matching placebo performed in theminutes preceding PCI. The primary efficacy end point of CIRCUS is a composite of 1-year all-cause mortality, rehospitalization for heart failure or heart failure worsening during initial hospitalization, and left ventricular adverse remodeling as determined by sequential transthoracic echochardiography. Secondary outcomes will be tested using a hierarchical sequence of left ventricular (LV) ejection fraction and absolute measurements of LV volumes. The composite of death and rehospitalization for heart failure or heart failure worsening during initial hospitalization will be further assessed at three years after the initial infarction. Results Recruitment lasted from April 2011 to February 2014. The CIRCUS trial has recruited 975 patients with acute anterior myocardial infarction. The 12-months results are expected to be available in 2015. Conclusions The CIRCUS trial is testing the hypothesis that cyclosporine in addition to early revascularization with PPCI compared to placebo in patients with acute anterior myocardial infarction reduces the incidence of death, heart failure and adverse LV remodeling at one-year follow-up.
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| 17. |
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| 18. |
- Munch Elmér, Anette, et al.
(author)
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Ion Conductive Electrolyte Membranes Based on Co-Continuous Polymer Blends
- 2003
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In: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 1364-5501. ; 13:9, s. 2168-2176
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Journal article (peer-reviewed)abstract
- Solid electrolyte membranes based on comb-shaped poly(ethylene glycol) (PEG) doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt in blends with poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) have been studied. Membranes containing between 70 and 100 wt% PEG were prepared by a convenient two-step process where films containing a mixture of mono- and dimethacrylate-terminated PEG macromonomers, PVDF-HFP, LiTFSI, and a photoactivator were cast from acetone solutions, followed by UV-initiated polymerization of the macromonomers. Microscopy of the membranes revealed a phase separated morphology with a microporous PVDF-HFP network embedded in comb-shaped PEG. The membranes were thermally stable at temperatures below the melting point of PVDF-HFP at 140 °C. Dynamic mechanical analysis (DMA) in the tension mode showed that the mechanical properties of the membranes were greatly improved both by the addition of PVDF-HFP and of dimethacrylate-terminated PEG macromonomer. For example, the storage modulus at 25 °C and 1 Hz showed a three-fold increase after increasing the percentage of dimethacrylate-terminated PEG from 0 to 10 wt% in the macromonomer mixture. A broad shoulder on tan as a function of temperature indicated the existence of a PVDF-HFP rich amorphous interphase. At room temperature, the membranes containing more than 80 wt% PEG reached ionic conductivities exceeding 10–5 S cm–1.
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| 19. |
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| 20. |
- Rytter, Anna, et al.
(author)
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The temperature dependence and involvement of mitochondria permeability transition and caspase activation in damage to organotypic hippocampal slices following in vitro ischemia.
- 2005
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In: Journal of Neurochemistry. - : Wiley. - 1471-4159 .- 0022-3042. ; 95:4, s. 1108-1117
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Journal article (peer-reviewed)abstract
- The aggravating effect of hyperglycemia on ischemic brain injury can be mimicked in a model of in vitro ischemia (IVI) using murine hippocampal slice cultures. Using this model, we found that the damage in the CA1 region following IVI in the absence or presence of 40 mM glucose (hyperglycemia) is highly temperature dependent. Decreasing the temperature from 35 to 31 degrees C during IVI prevented cell death, whereas increasing the temperature by 2 degrees C markedly aggravated damage. As blockade of the mitochondrial permeability transition (MPT) is equally effective as hypothermia in preventing ischemic cell death in vivo, we investigated whether inhibition of MPT or of caspases was protective following IVI. In the absence of glucose, the MPT blockers cyclosporin A and MeIle(4)-CsA but not the immunosuppressive compound FK506 diminished cell death. In contrast, following hyperglycemic IVI, MPT blockade was ineffective. Also, the pan-caspase inhibitor Boc-Asp(OMe)fluoromethyl ketone did not decrease cell death in the CA1 region following IVI or hyperglycemic IVI. We conclude that cell death in the CA1 region of organotypic murine hippocampal slices following IVI is highly temperature dependent and involves MPT. In contrast, cell death following hyperglycemic IVI, although completely prevented by hypothermia, is not mediated by mechanisms that involve MPT or caspase activation
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| 21. |
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| 22. |
- Smirnova, Oxana, et al.
(author)
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The end of HEP-specific computing as we know it?
- 2014
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In: 20th International Conference on Computing in High Energy and Nuclear Physics (Chep2013), Parts 1-6. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 513, s. 052033-052033
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Conference paper (peer-reviewed)abstract
- CHEP Conferences are dedicated to a quite specific scientific computing domain, and deal with rather specialised software, developed for the needs of the High Energy Physics community. The sheer size of this community created an environment which until recently has been to a large extent isolated from the mainstream computing. There is however an emerging trend for the computing solutions to spill outside the traditional laboratory boundaries, benefiting from becoming less domain-specific. This paper summarises the panel discussion held at the CHEP'13 conference with the goal to answer the questions, why the mainstream software approaches are not always suitable for the High Energy Physics community, and why its own solutions so far enjoyed little popularity in other domains?
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| 23. |
- Wirfält, Elisabet, et al.
(author)
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Comparison of food frequency questionnaires: the reduced Block and Willett questionnaires differ in ranking on nutrient intakes
- 1998
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In: American Journal of Epidemiology. - 0002-9262. ; 148:12, s. 1148-1156
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Journal article (peer-reviewed)abstract
- Food frequency questionnaires, major tools in epidemiologic studies, are often criticized for biased and imprecise intake estimates. The aim of this study was to compare the performance of two widely used food frequency questionnaires, a reduced 60-item Block questionnaire and a 153-item Willett food frequency questionnaire, relative to three 24-hour recalls administered by telephone. The dietary data were collected in 1991 from a group of healthy women age 25-49 years (n=101) during the baseline period of a weight-loss intervention study in Minneapolis, Minnesota. Total energy and macro- and micronutrient intakes were compared across methods by using four analytic approaches: comparison of means and correlation coefficients, regression analysis, and estimation of percent agreement between each questionnaire and recalls. The Block instrument showed an overall underestimation bias, but was more successful in categorizing individuals on percent energy from fat and carbohydrate intakes than was the Willett instrument. The Willett instrument showed no overall underestimation bias and was more successful in classifying individuals on vitamin A and calcium intakes. Diverging performance characteristics of diet assessment methods have an implication for the design of studies, interpretation of results, and comparison of findings across studies.
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