ABSTRACT
We report the observation of new properties of primary iron (Fe) cosmic rays in the rigidity range 2.65 GV to 3.0 TV with 0.62×10^{6} iron nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. Above 80.5 GV the rigidity dependence of the cosmic ray Fe flux is identical to the rigidity dependence of the primary cosmic ray He, C, and O fluxes, with the Fe/O flux ratio being constant at 0.155±0.006. This shows that unexpectedly Fe and He, C, and O belong to the same class of primary cosmic rays which is different from the primary cosmic rays Ne, Mg, and Si class.
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BACKGROUND & AIMS: Chronic liver disease is a major health burden that produces significant liver-related morbidity and mortality. We aimed to evaluate liver-related outcomes of patients with different causes of chronic liver disease in Australia. METHODS: We collected data from 10,933 patients with chronic liver disease assessed by Hepascore (a serum fibrosis model) in Western Australia from 2004 through 2015. We obtained records of liver-related death, transplantation, decompensation, and hepatocellular carcinoma from WA Data Linkage Unit databases. Competing risk analysis was used to calculate the cumulative risk of each clinical endpoint, and risks for clinical endpoints were compared among all causes of chronic liver disease. RESULTS: In our final cohort for analysis, 5566 patients had hepatitis C virus (HCV) infection, 1989 had HBV infection, 119 were infected with HBV and HCV, 955 had alcohol-associated liver disease, 1597 had non-alcoholic fatty liver disease (NAFLD), 123 had alcohol-associated liver disease and metabolic risk factors, 561 had autoimmune liver disease without overlap syndrome, and 23 autoimmune overlap syndrome. Significant differences among chronic liver diseases were observed in risk of all-cause death (P < .001), liver-related death (P < .001), liver transplantation (P < .001), and decompensation (P < .001) but not hepatocellular carcinoma (P=.095). Patients with alcohol-associated liver disease had the highest 5-year cumulative risk of liver-related death (17.1%) and the second-highest 5-year cumulative risk of decompensation (29.2%). Multivariate analysis found patients with alcohol-associated liver disease had significantly higher risks of liver-related death and decompensation than patients with HCV infection with hazard ratios (HRs) of 2.39 (95% CI, 1.88-3.03) and 3.42 (95% CI, 2.74-4.27), respectively. Patients with NAFLD had a significantly lower risk of liver related death and decompensation than patients with HCV infection, with HRs of 0.67 (95% CI, 0.48-0.95) and 0.70 (95% CI, 0.52-0.94) respectively. CONCLUSIONS: In an analysis of patients in Western Australia, we found patients with alcohol-associated liver disease to have significantly higher risk of decompensation and liver-related death than patients with HCV infection, whereas patients with NAFLD have significantly lower risks of either outcome.
Subject(s)
Carcinoma, Hepatocellular , Hepatitis C, Chronic , Liver Neoplasms , Liver Transplantation , Carcinoma, Hepatocellular/epidemiology , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/epidemiology , Humans , Liver Cirrhosis , Liver Neoplasms/epidemiologyABSTRACT
We report the observation of new properties of primary cosmic rays, neon (Ne), magnesium (Mg), and silicon (Si), measured in the rigidity range 2.15 GV to 3.0 TV with 1.8×10^{6} Ne, 2.2×10^{6} Mg, and 1.6×10^{6} Si nuclei collected by the Alpha Magnetic Spectrometer experiment on the International Space Station. The Ne and Mg spectra have identical rigidity dependence above 3.65 GV. The three spectra have identical rigidity dependence above 86.5 GV, deviate from a single power law above 200 GV, and harden in an identical way. Unexpectedly, above 86.5 GV the rigidity dependence of primary cosmic rays Ne, Mg, and Si spectra is different from the rigidity dependence of primary cosmic rays He, C, and O. This shows that the Ne, Mg, and Si and He, C, and O are two different classes of primary cosmic rays.
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Precision results on cosmic-ray electrons are presented in the energy range from 0.5 GeV to 1.4 TeV based on 28.1×10^{6} electrons collected by the Alpha Magnetic Spectrometer on the International Space Station. In the entire energy range the electron and positron spectra have distinctly different magnitudes and energy dependences. The electron flux exhibits a significant excess starting from 42.1_{-5.2}^{+5.4} GeV compared to the lower energy trends, but the nature of this excess is different from the positron flux excess above 25.2±1.8 GeV. Contrary to the positron flux, which has an exponential energy cutoff of 810_{-180}^{+310} GeV, at the 5σ level the electron flux does not have an energy cutoff below 1.9 TeV. In the entire energy range the electron flux is well described by the sum of two power law components. The different behavior of the cosmic-ray electrons and positrons measured by the Alpha Magnetic Spectrometer is clear evidence that most high energy electrons originate from different sources than high energy positrons.
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Precision measurements of cosmic ray positrons are presented up to 1 TeV based on 1.9 million positrons collected by the Alpha Magnetic Spectrometer on the International Space Station. The positron flux exhibits complex energy dependence. Its distinctive properties are (a) a significant excess starting from 25.2±1.8 GeV compared to the lower-energy, power-law trend, (b) a sharp dropoff above 284_{-64}^{+91} GeV, (c) in the entire energy range the positron flux is well described by the sum of a term associated with the positrons produced in the collision of cosmic rays, which dominates at low energies, and a new source term of positrons, which dominates at high energies, and (d) a finite energy cutoff of the source term of E_{s}=810_{-180}^{+310} GeV is established with a significance of more than 4σ. These experimental data on cosmic ray positrons show that, at high energies, they predominantly originate either from dark matter annihilation or from other astrophysical sources.
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Precision measurements by the Alpha Magnetic Spectrometer (AMS) on the International Space Station of ^{3}He and ^{4}He fluxes are presented. The measurements are based on 100 million ^{4}He nuclei in the rigidity range from 2.1 to 21 GV and 18 million ^{3}He from 1.9 to 15 GV collected from May 2011 to November 2017. We observed that the ^{3}He and ^{4}He fluxes exhibit nearly identical variations with time. The relative magnitude of the variations decreases with increasing rigidity. The rigidity dependence of the ^{3}He/^{4}He flux ratio is measured for the first time. Below 4 GV, the ^{3}He/^{4}He flux ratio was found to have a significant long-term time dependence. Above 4 GV, the ^{3}He/^{4}He flux ratio was found to be time independent, and its rigidity dependence is well described by a single power law âR^{Δ} with Δ=-0.294±0.004. Unexpectedly, this value is in agreement with the B/O and B/C spectral indices at high energies.
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We present the precision measurement from May 2011 to May 2017 (79 Bartels rotations) of the proton fluxes at rigidities from 1 to 60 GV and the helium fluxes from 1.9 to 60 GV based on a total of 1×10^{9} events collected with the Alpha Magnetic Spectrometer aboard the International Space Station. This measurement is in solar cycle 24, which has the solar maximum in April 2014. We observed that, below 40 GV, the proton flux and the helium flux show nearly identical fine structures in both time and relative amplitude. The amplitudes of the flux structures decrease with increasing rigidity and vanish above 40 GV. The amplitudes of the structures are reduced during the time period, which started one year after solar maximum, when the proton and helium fluxes steadily increase. Above â¼3 GV the p/He flux ratio is time independent. We observed that below â¼3 GV the ratio has a long-term decrease coinciding with the period during which the fluxes start to rise.
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A precision measurement of the nitrogen flux with rigidity (momentum per unit charge) from 2.2 GV to 3.3 TV based on 2.2×10^{6} events is presented. The detailed rigidity dependence of the nitrogen flux spectral index is presented for the first time. The spectral index rapidly hardens at high rigidities and becomes identical to the spectral indices of primary He, C, and O cosmic rays above â¼700 GV. We observed that the nitrogen flux Φ_{N} can be presented as the sum of its primary component Φ_{N}^{P} and secondary component Φ_{N}^{S}, Φ_{N}=Φ_{N}^{P}+Φ_{N}^{S}, and we found Φ_{N} is well described by the weighted sum of the oxygen flux Φ_{O} (primary cosmic rays) and the boron flux Φ_{B} (secondary cosmic rays), with Φ_{N}^{P}=(0.090±0.002)×Φ_{O} and Φ_{N}^{S}=(0.62±0.02)×Φ_{B} over the entire rigidity range. This corresponds to a change of the contribution of the secondary cosmic ray component in the nitrogen flux from 70% at a few GV to <30% above 1 TV.
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We present high-statistics, precision measurements of the detailed time and energy dependence of the primary cosmic-ray electron flux and positron flux over 79 Bartels rotations from May 2011 to May 2017 in the energy range from 1 to 50 GeV. For the first time, the charge-sign dependent modulation during solar maximum has been investigated in detail by leptons alone. Based on 23.5×10^{6} events, we report the observation of short-term structures on the timescale of months coincident in both the electron flux and the positron flux. These structures are not visible in the e^{+}/e^{-} flux ratio. The precision measurements across the solar polarity reversal show that the ratio exhibits a smooth transition over 830±30 days from one value to another. The midpoint of the transition shows an energy dependent delay relative to the reversal and changes by 260±30 days from 1 to 6 GeV.
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We report on the observation of new properties of secondary cosmic rays Li, Be, and B measured in the rigidity (momentum per unit charge) range 1.9 GV to 3.3 TV with a total of 5.4×10^{6} nuclei collected by AMS during the first five years of operation aboard the International Space Station. The Li and B fluxes have an identical rigidity dependence above 7 GV and all three fluxes have an identical rigidity dependence above 30 GV with the Li/Be flux ratio of 2.0±0.1. The three fluxes deviate from a single power law above 200 GV in an identical way. This behavior of secondary cosmic rays has also been observed in the AMS measurement of primary cosmic rays He, C, and O but the rigidity dependences of primary cosmic rays and of secondary cosmic rays are distinctly different. In particular, above 200 GV, the secondary cosmic rays harden more than the primary cosmic rays.
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We report the observation of new properties of primary cosmic rays He, C, and O measured in the rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, and 7.0×10^{6} oxygen nuclei collected by the Alpha Magnetic Spectrometer (AMS) during the first five years of operation. Above 60 GV, these three spectra have identical rigidity dependence. They all deviate from a single power law above 200 GV and harden in an identical way.
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INTRODUCTION: Children growing up with haemophilia are at greater risk for psychosocial problems than their healthy peers. Providing psychosocial care to children with haemophilia and their families is indispensable, since psychosocial factors can have a significant impact on health and health-related quality of life (HRQOL). AIMS: Our aim was to give a description of psychosocial care provided by the multidisciplinary team of the Hemophilia Comprehensive Care Centre (HCCC) at the Emma Children's Hospital in Amsterdam, the Netherlands. With this overview, other caregivers and hospitals can benefit in organizing their psychosocial care for children with haemophilia. METHODS: The focus of the psychosocial care provided by the multidisciplinary team is on preventing psychosocial problems and medical-related stress, and supporting and equipping the child with haemophilia and its parents with as many skills as possible to lead an independent life with a high HRQOL. RESULTS: Core elements of the psychosocial care are therefore monitoring and screening of HRQOL (e.g. in daily clinical practice via www.hetklikt.nu), psychoeducation (haemophilia camp, haemophilia school, disease-specific activities, meetings for girls, parent meetings), practical help (Emma at Work, an employment agency for adolescents and young adults; Educational Facility and school visits), psychosocial interventions (the On Track group intervention and the Haemophilia Coping and Perception Test) and individual care (psychological counselling and referrals). CONCLUSION: By providing this overview of psychosocial support offered and by sharing this knowledge, psychosocial care can become more structured and consistent between HCCCs around the world. Potentially, processes and outcomes of care can be improved.
Subject(s)
Hemophilia A/psychology , Parents/psychology , Patient Care/methods , Patient Care/psychology , Child , Humans , Netherlands , Quality of LifeABSTRACT
A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range â¼60 to â¼500 GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From â¼60 to â¼500 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.
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Knowledge of the rigidity dependence of the boron to carbon flux ratio (B/C) is important in understanding the propagation of cosmic rays. The precise measurement of the B/C ratio from 1.9 GV to 2.6 TV, based on 2.3 million boron and 8.3 million carbon nuclei collected by AMS during the first 5 years of operation, is presented. The detailed variation with rigidity of the B/C spectral index is reported for the first time. The B/C ratio does not show any significant structures in contrast to many cosmic ray models that require such structures at high rigidities. Remarkably, above 65 GV, the B/C ratio is well described by a single power law R^{Δ} with index Δ=-0.333±0.014(fit)±0.005(syst), in good agreement with the Kolmogorov theory of turbulence which predicts Δ=-1/3 asymptotically.
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The dilution effect, that high host species diversity can reduce disease risk, has attracted much attention in the context of global biodiversity decline and increasing disease emergence. Recent studies have criticized the generality of the dilution effect and argued that it only occurs under certain circumstances. Nevertheless, evidence for the existence of a dilution effect was reported in about 80% of the studies that addressed the diversity-disease relationship, and a recent meta-analysis found that the dilution effect is widespread. We here review supporting and critical studies, point out the causes underlying the current disputes. The dilution is expected to be strong when the competent host species tend to remain when species diversity declines, characterized as a negative relationship between species' reservoir competence and local extinction risk. We here conclude that most studies support a negative competence-extinction relationship. We then synthesize the current knowledge on how the diversity-disease relationship can be modified by particular species in community, by the scales of analyses, and by the disease risk measures. We also highlight the complex role of habitat fragmentation in the diversity-disease relationship from epidemiological, evolutionary and ecological perspectives, and construct a synthetic framework integrating these three perspectives. We suggest that future studies should test the diversity-disease relationship across different scales and consider the multiple effects of landscape fragmentation.
Subject(s)
Biodiversity , Ecosystem , Host-Pathogen Interactions/physiology , Infections/epidemiology , Animals , Disease Vectors , Extinction, Biological , Humans , Infections/transmission , Risk FactorsABSTRACT
Decomposition of wood is an important component of global carbon cycling. Most wood decomposition models are based on tree characteristics and environmental conditions; however, they do not include community dynamics of fungi that are the major wood decomposers. We examined the factors explaining variation in sapwood decay in oak tree stumps two and five years after cutting. Wood moisture content was significantly correlated with sapwood decay in younger stumps, whereas ITS-based composition and species richness of the fungal community were the best predictors for mass loss in the older stumps. Co-occurrence analysis showed that, in freshly cut trees and in younger stumps, fungal communities were nonrandomly structured, whereas fungal communities in old stumps could not be separated from a randomly assembled community. These results indicate that the most important factors explaining variation in wood decay rates can change over time and that the strength of competitive interactions between fungi in decaying tree stumps may level off with increased wood decay. Our field analysis further suggests that ascomycetes may have a prominent role in wood decay, but their wood-degrading abilities need to be further tested under controlled conditions. The next challenging step will be to integrate fungal community assembly processes in wood decay models to improve carbon sequestration estimates of forests.
Subject(s)
Fungi , Microbial Consortia , Quercus/microbiology , Soil Microbiology , Wood/microbiologyABSTRACT
A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.
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Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.
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BACKGROUND AND AIMS: Rates of long-term clinical outcomes of chronic hepatitis C in patients with none, mild or severe liver fibrosis are required to determine benefits of anti-viral therapies. This study evaluated long-term outcomes for chronic hepatitis C stratified by all Metavir fibrosis stages. METHODS: Clinical outcomes were determined using population-based data linkage methodology for 880 hepatitis C patients who had a liver biopsy performed from 1992 to 2012. RESULTS: During 9386 person-years of follow up, 28 patients developed hepatocellular carcinoma, 58 developed liver decompensation and 122 died or underwent liver transplantation. There was no significant difference in liver-related death for those with F0-F2 with an 18-year survival probability >94%. Hazard ratio of liver-related death for F3 compared with F0-F2 was 4.24 (P = 0.003), with no significant difference in the first 13-year follow up. The 15-year decompensation-free survival for F0, F1 and F2 was 100%, 96% and 94% respectively and for hepatocellular carcinoma-free survival was 100%, 99% and 98%. Hazard ratio of liver complication (hepatocellular carcinoma or decompensation)-free survival for F3 compared with F0-F2 was 3.22 (P = 0.001), with no significant difference during the first 7-year follow up. F4 had significantly higher risk of liver-related death, decompensation and hepatocellular carcinoma than F3 (P < 0.001). CONCLUSIONS: Chronic hepatitis C patients with F2 or less had few liver complications after 15 years. For F3 patients, the significant increase in liver-related death occurred after 13 years and for liver complications after 7 years.
Subject(s)
Carcinoma, Hepatocellular/etiology , Hepatitis C, Chronic/complications , Hospitals/statistics & numerical data , Liver Cirrhosis/etiology , Liver Neoplasms/etiology , Liver Transplantation/statistics & numerical data , Adult , Aged , Aged, 80 and over , Biopsy , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/epidemiology , Disease Progression , Female , Follow-Up Studies , Hepatitis C, Chronic/diagnosis , Hepatitis C, Chronic/surgery , Humans , Incidence , Liver/pathology , Liver Cirrhosis/diagnosis , Liver Cirrhosis/epidemiology , Liver Neoplasms/diagnosis , Liver Neoplasms/epidemiology , Male , Middle Aged , Retrospective Studies , Survival Rate/trends , Western Australia/epidemiologyABSTRACT
BACKGROUND & AIMS: Histopathological scoring of liver fibrosis mainly measures architectural abnormalities and requires a minimum biopsy size (⩾ 10 mm). Liver collagen quantification may allow use of small size biopsies and improve the prediction of clinical outcomes. This study evaluated the ability of the collagen proportional area (CPA) measurement to predict clinical outcomes. METHODS: Clinical outcomes were determined using population based data-linkage for chronic hepatitis C (CHC) patients from 1992 to 2012. Quantitative digital image analysis of liver biopsies was used for CPA measurement. RESULTS: 533 patients with a biopsy size ⩾ 5 mm were included. Median follow up was 10.5 years. 26 developed hepatocellular carcinoma (HCC), 39 developed liver decompensation and 33 had liver related death. 453 had Metavir F0-F2 and 80 had F3-F4. CPA ranged from 1.3% to 44.6%. CPA and Metavir stage were independently associated with liver related death. Metavir stage, CPA stage and age were independently associated with HCC. CPA stage (C1: 0%-5%, C2: 5%-10%, C3: 10%-20%, C4: >20%) stratified risk and a significant difference in outcomes was present between all CPA stages for HCC and between C2-C3 and C3-C4 for decompensation and liver related death. The 15 year composite endpoint-free survival was 97% for C1, 89% for C2, 60% for C3, 7% for C4. C4 had significantly worse survival than ⩽ C3 (p<0.001) in cirrhotic patients. CONCLUSIONS: CPA stage gave additional information regarding risk stratification for adverse clinical outcomes independent of Metavir stage.