In the framework of quantum chromodynamics (QCD), parton distribution functions (PDFs) quantify how the momentum and spin of a hadron are divided among its quark and gluon constituents. Two main ...approaches exist to determine PDFs. The first approach, based on QCD factorization theorems, realizes a QCD analysis of a suitable set of hard-scattering measurements, often using a variety of hadronic observables. The second approach, based on first-principle operator definitions of PDFs, uses lattice QCD to compute directly some PDF-related quantities, such as their moments. Motivated by recent progress in both approaches, in this document we present an overview of lattice-QCD and global-analysis techniques used to determine unpolarized and polarized proton PDFs and their moments. We provide benchmark numbers to validate present and future lattice-QCD calculations and we illustrate how they could be used to reduce the PDF uncertainties in current unpolarized and polarized global analyses. This document represents a first step towards establishing a common language between the two communities, to foster dialogue and to further improve our knowledge of PDFs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In a follow-up to a 1-year study involving patients who had a TIA or minor stroke, the rate of cardiovascular events including stroke was 6.4% in the first year and 6.4% in the second through fifth ...years.
Failure modes of spot friction welds made by a concave tool in lap-shear specimens of aluminum 6111-T4 sheets are first investigated based on experimental observations. Optical and scanning electron ...micrographs of the welds before and after failure under quasi-static and cyclic loading conditions are examined. The micrographs show that the failure modes of the welds under quasi-static and cyclic loading conditions are quite different. Under quasi-static loading conditions, the failure mainly starts from the necking of the upper sheet outside the weld. Under cyclic loading conditions, the experimental observations indicate two types of fatigue cracks. One type initiates and grows into the lower sheet outside the stir zone and another type initiates from the bend surface of the upper sheet outside the weld. The dominant fatigue cracks for the final failures of the welds are the kinked fatigue cracks growing in the lower sheet outside the stir zone. Based on the experimental observations of the paths of the dominant kinked fatigue cracks, a fatigue crack growth model is then adopted to estimate the fatigue lives of the spot friction welds. The global stress intensity factors and the local stress intensity factors for kinked cracks based on the recent published works for resistance spot welds and the Paris law for crack propagation are used in the fatigue crack growth model. The fatigue life estimations based on the fatigue crack growth model with the global and local stress intensity factors as functions of the kink length and the experimentally determined kink angles agree well with the experimental results.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
White matter (WM) injury in carbon monoxide (CO) intoxication is thought to be related to delayed cognitive sequelae. To determine if microstructural changes in WM are responsible for the delayed ...onset of cognitive symptoms, we performed diffusion tensor imaging (DTI) in patients with CO intoxication.
DTI was performed in 14 patients with delayed sequelae after CO intoxication and in 16 sex- and age-matched healthy volunteers. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of several WM regions were measured. We also determined the correlation between FA of the selected WM and neuropsychological rating scores for the CO intoxication group.
FA of patients with CO intoxication decreased in the corpus callosum, orbitofrontal WM, high frontal WM, parietal WM, and temporal lobes in comparison with the corresponding regions of healthy controls. FA of the WM in the occipital lobe and internal capsule of patients was not significantly different from that in controls. ADCs of all measured WM increased significantly in patients exposed to CO. High correlations were found between the FA of all selected WM and the Mini-Mental State Examination score (gamma = 0.631, P = .016) and the digit span backward task (gamma = 0.759, P = .001).
CO intoxication may cause FA decline in associated cortical areas. This observation indicates microstructural WM pathology in CO intoxication, which is related to delayed cognitive encephalopathy.
Objectives
To assess the prognostic performance of a new N classification that incorporates the log odds of positive lymph nodes (LODDS) into the routinely used pathological N classification for oral ...squamous cell carcinoma (OSCC) patients.
Design
Retrospective cohort study utilising LODDS into pN category was performed, and the AJCC TNM stage and T‐New N‐M stage were compared with respect to 5‐year disease‐specific survival (DSS) rates. The discriminability was evaluated from the linear trend chi‐square test, Akaike information criterion (AIC) and Harrell's c‐statistic.
Setting
Medical centrer in Taiwan.
Participants
A total of 463 patients received primary surgery and neck dissection between 2004 and 2013 for OSCC.
Main outcome measures
The discriminability for 5‐year DSS rates.
Results
The median follow‐up period was 54 months, the mean patient age was 54 ± 11 years and 428 patients (92.4%) were male. The patients with higher LODDS had worse 5‐year DSS rates. Incorporation of LODDS into the prognostic model based on the seventh edition of the TNM classification significantly improved discriminative performance for 5‐year DSS with a lower AIC (1883 versus 1897), and higher prediction accuracy (Harrell's c‐statistic: 0.768 versus 0.764).
Conclusions
By utilising a merger of the LODDS and pN classifications to create a new N classification has better discriminatory and predictive ability than pathological TNM staging and could help identify high‐risk patients for intense adjuvant therapy.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
This descriptive study aimed to explore the physiological factors that determine tolerance to exertion during high-intensity interval effort. Forty-seven young women (15-28 years old) were enrolled: ...23 athletes from Taiwan national or national reserve teams and 24 moderately active females. Each participant underwent a maximal incremental INC (modified Bruce protocol) cardiopulmonary exercise test on the first day and high-intensity interval testing (HIIT) on the second day, both performed on a treadmill. The HIIT protocol involved alternation between 1-min effort at 120% of the maximal speed, at the same slope reached at the end of the INC, and 1-min rest until volitional exhaustion. Gas exchange, heart rate (HR), and muscle oxygenation at the right vastus lateralis, measured by near-infrared spectroscopy, were continuously recorded. The number of repetitions completed (Rlim) by each participant was considered the HIIT tolerance index. The results showed a large difference in the Rlim (range, 2.6-12.0 repetitions) among the participants. Stepwise linear regression revealed that the variance in the Rlim within the cohort was related to the recovery rates of oxygen consumption (Formula: see text), HR at the second minute after INC, and muscle tissue saturation index at exhaustion (R = 0.644). In addition, age was linearly correlated with Rlim (adjusted R = -0.518, p < 0.0001). In conclusion, the recovery rates for Formula: see text and HR after the incremental test, and muscle saturation index at exhaustion, were the major physiological factors related to HIIT performance. These findings provide insights into the role of the recovery phase after maximal INC exercise testing. Future research investigating a combination of INC and HIIT testing to determine training-induced performance improvement is warranted.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Failure modes of spot friction welds made by a flat tool in lap-shear specimens of aluminum 6111-T4 sheets are investigated based on the approach presented in Part 1. Optical and scanning electron ...micrographs of the welds before and after failure under quasi-static and cyclic loading conditions are examined. The micrographs show that the microstructure, geometry, and the failure modes of the welds made by the flat tool are quite different from those of the welds made by a concave tool. Under quasi-static loading conditions, the failure mainly starts from cracking near the boundary of the stir zone close to the upper sheet surface inside the weld. Under cyclic loading conditions, the experimental results indicate three types of fatigue cracks. The first type initiates and grows near the boundary of the stir zone close to the upper sheet surface inside the weld as that under quasi-static loading conditions. The second type initiates and grows into the lower sheet outside the stir zone. The third type initiates from the bend surface of the upper sheet outside the weld. Under low-cycle loading conditions, the dominant kinked fatigue cracks are the first type growing near the boundary of the stir zone. Under high-cycle loading conditions, the dominant kinked fatigue cracks are the second type growing in the lower sheet outside the stir zone. Based on the experimental observations of the paths of the dominant kinked fatigue cracks, the fatigue crack growth model presented in Part 1 is then adopted to estimate the fatigue lives of the spot friction welds made by the flat tool. The fatigue life estimations based on the fatigue crack growth model with the global and local stress intensity factors as functions of the kink length and the experimentally determined kink angles agree well with the experimental results. A comparison of the experimental results suggests that the failure strengths of spot friction welds under quasi-static loading condition can cautiously be used as references to select a tool and the corresponding processing parameters. However, fatigue tests must be performed to validate the performance of spot friction welds under cyclic loading conditions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PSR J2021+4026 is a radio-quiet gamma-ray pulsar and the first pulsar that shows state change of the gamma-ray emission and spindown rate. The state change of PSR J2021+4026 was first observed at ...2011 October, at which the pulsar changes the state from high gamma-ray flux/low spindown rate state to low gamma-ray flux/high spindown rate state. In 2014 December, PSR J2021+4026 recovered the state before the 2011 state change over a timescale of a few months. We report that the long-term evolution of the gamma-ray flux and timing behavior suggests that PSR J2021+4026 changed the state near 2018 February 1 and entered a new low gamma-ray flux/high spindown rate state. At the 2018 state change, the averaged flux dropped from (1.29 0.01) × 10−6 cts cm−2 s−1 to (1.12 0.01) × 10−6 cts cm−2 s−1, which is behavior similar to that of the 2011 event. The spindown rate has increased by ∼3% in the new state since the 2018 state change. The shapes of pulse profile and spectrum in GeV bands also changed at the 2018 event, and they are consistent with behavior at the 2011 state change. Our results probably suggest that PSR J2021+4026 is switching between different states with a timescale of several years, like some radio pulsars (e.g., PSR B1828-11). PSR J2021+4026 will provide a unique opportunity to study the mechanism of the state switching.
Metabolic reprogramming by oncogenic signals promotes cancer initiation and progression. The oncogene KRAS and tumour suppressor STK11, which encodes the kinase LKB1, regulate metabolism and are ...frequently mutated in non-small-cell lung cancer (NSCLC). Concurrent occurrence of oncogenic KRAS and loss of LKB1 (KL) in cells specifies aggressive oncological behaviour. Here we show that human KL cells and tumours share metabolomic signatures of perturbed nitrogen handling. KL cells express the urea cycle enzyme carbamoyl phosphate synthetase-1 (CPS1), which produces carbamoyl phosphate in the mitochondria from ammonia and bicarbonate, initiating nitrogen disposal. Transcription of CPS1 is suppressed by LKB1 through AMPK, and CPS1 expression correlates inversely with LKB1 in human NSCLC. Silencing CPS1 in KL cells induces cell death and reduces tumour growth. Notably, cell death results from pyrimidine depletion rather than ammonia toxicity, as CPS1 enables an unconventional pathway of nitrogen flow from ammonia into pyrimidines. CPS1 loss reduces the pyrimidine to purine ratio, compromises S-phase progression and induces DNA-polymerase stalling and DNA damage. Exogenous pyrimidines reverse DNA damage and rescue growth. The data indicate that the KL oncological genotype imposes a metabolic vulnerability related to a dependence on a cross-compartmental pathway of pyrimidine metabolism in an aggressive subset of NSCLC.
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IJS, KISLJ, NUK, SBMB, UL, UM, UPUK
The etiology of systemic lupus erythematosus (SLE) involves a complex interaction of genetic and environmental factors. Investigations have shown that environmentally driven epigenetic changes ...contribute to the etiology of SLE. Here, we hypothesize that aberrant DNA methylation may contribute to the activation of the immune machinery and trigger lupus disease activity. A whole genome methylation array was applied to investigate the DNA methylation changes between 12 pairs of active SLE patients and healthy controls. The results were further confirmed in 66 SLE patients, 102 healthy controls. The methylation statuses of the IL10 and IL1R2 genes were significantly reduced in the SLE patient samples relative to the healthy controls (age-adjusted odds ratios, 64.2 and 16.9, respectively, P<0.0001). There was a trend toward SLE patients having hypomethylated IL10 and IL1R2 genes accompanied by greater disease activity. We observed that the methylation degree of IL10 and IL1R2 genes were reduced in the rheumatoid arthritis (RA) patients as well but the hypomethylation change was more significant in IL1R2 genes than in the IL10 genes in RA patients. This study demonstrated that DNA hypomethylation might be associated with SLE. Hypomethylated IL10 and IL1R2 genes may provide potential epigenetic markers as clinical predictors for autoimmune diseases.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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