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An ultrafast x-ray detector system is under development at Lawrence Berkeley National Laboratory (LBNL) for application primarily to studyies of ultrafast magnetization dynamics. The system consists of a fs laser, an x-ray streak camera and an ellipitically polarization undulator (EPU) beamline. Polarized x-rays from an EPU can be used to measure x-ray magnetic circular dichroism (XMCD) of a sample. XMCD has the unique ability to independently measure orbit and spin magnetization with sub-monolayer sensitivity and element specificity. The streak camera has simultaneously a sub-picosecond temporal resolution and a high spatial resolution. The combination of the streak camera and EPU allows us to study the transfer of angular momentum from spin to orbit to the lattice in the sample on an ultrafast time scale. We describe here the performance of the ultrafast detector, the laser and the x-ray synchronization system. The observation of the demagnetization process of different samples demonstrates the ability of the apparatus.

An x-ray streak camera with high resolution in both temporal and spatial dimensions has been developed. It is achieved by using extraction-mesh acceleration and a large opening aperture magnetic solenoid lens design. High resolutions in the temporal and spatial dimensions can be retained in a wide 53 ps time window. A temporal resolution of 233 fs and a spatial resolution of 10 m have been demonstrated using an Au photocathode.

BACKGROUND: Limited research has been conducted on the association between intake of fruits and vegetables and hypertriglyceridemia, especially in Asian populations. This study aimed to investigate the association between total fruit and vegetable intake, as well as subgroups of fruit and vegetable intake, with hypertriglyceridemia among Korean adults. METHODS: We conducted a cross-sectional study of 7934 adults aged 19-64 years from the fourth Korean Health and Nutrition Examination Survey. Fruit and vegetable intake was estimated from a food frequency questionnaire. Subgroups of fruits and vegetables included citrus, non-citrus and carotene-rich fruits and cruciferous, green leafy and carotene-rich vegetables. Hypertriglyceridemia (plasma triglyceride [greater than or equal to] 150 mg/dl) was diagnosed using a blood sample drawn after 12+ hours of fasting. RESULTS: There were 2001 (25.2%) cases of hypertriglyceridemia among the participants. Total fruit intake was significantly inversely associated with the prevalence of hypertriglyceridemia; the multivariate odds ratios (95% confidence intervals) of hypertriglyceridemia across increasing quintiles were 1.00 (ref), 0.76 (0.62, 0.92), 0.72 (0.58, 0.90), 0.68 (0.54, 0.85) and 0.64 (0.49, 0.82; [P.sub.trend] = 0.001) after controlling for survey year, body mass index, waist circumference, smoking, alcohol drinking, physical activity, education and income. Similar inverse associations were found for all fruit subgroups. However, we found no significant association between intakes of total or subgroups of vegetable and hypertriglyceridemia; the odds ratio for top vs bottom quintile was 1.00 (0.81-1.24) for total vegetable intake. CONCLUSIONS: Our findings support a potential beneficial role of fruit consumption to reduce blood triglyceride levels in Asian populations. European Journal of Clinical Nutrition (2015) 69, 1193-1199;doi:10.1038/ejcn.2015.77;published online 27 May 2015, INTRODUCTION Hypertriglyceridemia (elevated plasma triglyceride levels) is a strong risk factor for cardiovascular disease (1) and is frequently accompanied by other lipid abnormalities, obesity and the metabolic syndrome, which are [...]

This paper presents a parallel machine scheduling problem with rework probabilities, due-dates and sequence-dependent setup times. It is assumed that rework probability for each job on a machine can be given through historical data acquisition. Since the problem is NP-hard in the strong sense, a heuristic algorithm is presented, which finds good solutions. The dispatching algorithm named MRPD (minimum rework probability with due-dates) is proposed in this paper focusing on the rework processes. The performance of MRPD is measured by the six diagnostic indicators: total tardiness, maximum lateness, mean flow-time, mean lateness, the number of reworks and the number of tardy jobs. A large number of test problems are randomly generated to evaluate the performance of the proposed algorithm. Computational results show that the proposed algorithm is significantly superior to existing dispatching algorithms for the test problems. Journal of the Operational Research Society (2010) 61, 144-155. doi:10.1057/jors.2008.148 Published online 7 January 2009 Keywords: rework probability; parallel machines; dispatching algorithm; sequence-dependent setup times

The electronic structures of Ag[Ni.sub.1-x][Co.sub.x][O.sub.2] (0 [less than or equal to] x [less than or equal to] 1) delafossite oxides have been investigated by employing photoemission spectroscopy (PES) and X-ray absorption spectroscopy (XAS) in the soft X-ray regime of synchrotron radiation. The Ag 3d core-level PES spectra shift toward the higher binding energy with increasing x, in agreement with the metallic nature for low values of x and the insulating nature for high values of x in Ag[Ni.sub.1-x][Co.sub.x][O.sub.2]. Further, the Ag 3d core-level PES spectra become more asymmetric with decreasing x, which reflects the larger number of electron-hole pairs in the Ni-rich regime. Valence-band PES spectra reveal that the band width of the occupied Ni 3d states is broader than that of the Co 3d states, implying the larger Ni 3d-O 2p hybridization than the Co 3d-O 2p hybridization. The Co and Ni 2p XAS spectra show that Co ions are in the low-spin [Co.sup.3+] states for all x, while Ni ions are in the [Ni.sup.2+] - [Ni.sup.3+] mixed-valent states. The [Ni.sup.3+] component increases with x. Index Terms--Delafossite, electronic structure, PES, synchrotron radiation, XAS.

The valence states and electronic structures of transition-metal ions in spinel [Fe.sub.1-x][Cu.sub.x] [Cr.sub.2] [S.sub.4] (0.1 [less than or equal to] x [less than or equal to] 0.5) have been investigated by using scanning photoelectron microscopy (SPEM), photoemission spectroscopy (PES), soft-X-ray absorption spectroscopy (XAS), and soft X-ray magnetic circular dichroism (XMCD). The experimental data have been compared to the calculated density of states (DOS). It is found that the valence states of Cr and Cu ions are nearly trivalent ([Cr.sup.3+]) and monovalent ([Cu.sup.+]), respectively. The Fe 2p XAS spectra of [Fe.sub.1-x][Cu.sub.2][Cr.sub.2] [S.sub.4] are very similar to that of Fe metal, indicating that Fe 3d states are strongly hybridized to S 3p states. The XMCD measurements for Fe, Cr, and Cu 2p states show evidence that the magnetic moments of Cr ions are antiparallel to those of Fe ions and that Cu ions are weakly polarized parallel to Fe ions. Valence-band PES reveals that Cr 3d states are located at ~ -1.5 eV, while Fe 3d states are very broad, in agreement with the calculated DOS. This study indicates that the minority-spin [e.sub.g] states of Fe 3d electrons are located very close to EF, suggesting that the hybridized Fe [e.sub.g]-S 3p states near EF play an important role in determining the transport properties of [Fe.sub.1]-x [Cu.sub.x[Cr.sub.2][S.sub.4] for x [less than oe equal to] 0.5. Index Terms--Fe[Cr.sub.2][S.sub.4], [Fe.sub.0.5][Cu.sub.0.5][Cr.sub.2] [S.sub.4], photoemission spectroscopy (PES), scanning photoelectron microscopy (SPEM), spinel, X-ray absorption spectroscopy (XAS), X-ray magnetic circular dichroism (XMCD).