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A global atmospheric electricity monitoring network for climate and geophysical research
The Global atmospheric Electric Circuit (GEC) is a fundamental coupling network of the climate system connecting electrically disturbed weather regions with fair weather regions across the planet. The GEC sustains the fair weather electric field (or potential gradient, PG) which is present globally and can be measured routinely at the surface using durable instrumentation such as modern electric field mills, which are now widely deployed internationally. In contrast to lightning or magnetic fields, fair weather PG cannot be measured remotely. Despite the existence of many PG datasets (both contemporary and historical), few attempts have been made to coordinate and integrate these fragmented surface measurements within a global framework. Such a synthesis is important elvinin order to fully study major influences on the GEC such as climate variations and space weather effects, as well as more local atmospheric electrical processes such as cloud electrification, lightning initiation, and dust and aerosol charging.
The GloCAEM (Global Coordination of Atmospheric Electricity Measurements) project has brought together experts in atmospheric electricity to make the first steps towards an effective global network for atmospheric electricity monitoring, which will provide data in near real time. Data from all sites are available in identically-formatted files, at both one second and one minute temporal resolution, along with meteorological data (wherever available) for ease of interpretation of electrical measurements. This work describes the details of the GloCAEM database and presents what is likely to be the largest single analysis of PG data performed from multiple datasets at geographically distinct locations. Analysis of the diurnal variation in PG from all 17 GloCAEM sites demonstrates that the majority of sites show two daily maxima, characteristic of local influences on the PG, such as the sunrise effect. Data analysis methods to minimise such effects are presented and recommendations provided on the most suitable GloCAEM sites for the study of various scientific phenomena. The use of the dataset for a further understanding of the GEC is also demonstrated, in particular for more detailed characterization of day-to-day global circuit variability. Such coordinated effort enables deeper insight into PG phenomenology which goes beyond single-location PG measurements, providing a simple measurement of global thunderstorm variability on a day-to-day timescale. The creation of the GloCAEM database is likely to enable much more effective study of atmospheric electricity variables than has ever been possible before, which will improve our understanding of the role of atmospheric electricity in the complex processes underlying weather and climate
Enhanced erythrocyte antioxidant status following an 8-week aerobic exercise training program in heavy drinkers
© 2017 Elsevier Inc. Alcohol-induced oxidative stress is involved in the development and progression of various pathological conditions and diseases. On the other hand, exercise training has been shown to improve redox status, thus attenuating oxidative stress-associated disease processes. The purpose of the present study was to evaluate the effect of an exercise training program that has been previously reported to decrease alcohol consumption on blood redox status in heavy drinkers. In a non-randomized within-subject design, 11 sedentary, heavily drinking men (age: 30.3 ± 3.5 years; BMI: 28.4 ± 0.86 kg/m2) participated first in a control condition for 4 weeks, and then in an intervention where they completed an 8-week supervised aerobic training program of moderate intensity (50–60% of the heart rate reserve). Blood samples were collected in the control condition (pre-, post-control) as well as before, during (week 4 of the training program), and after intervention (week 8 of the training program). Samples were analyzed for total antioxidant capacity (TAC), thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), uric acid (UA), bilirubin, reduced glutathione (GSH), and catalase activity. No significant change in indices of redox status in the pre- and post-control was observed. Catalase activity increased (p < 0.05) after 8 weeks of intervention compared to week 4. GSH increased (p < 0.05) after 8 weeks of intervention compared to the control condition and to week 4 of intervention. TAC, UA, bilirubin, TBARS, and PC did not significantly change at any time point. Moreover, concentrations of GSH, TBARS, and catalase activity negatively correlated with alcohol consumption. In conclusion, an 8-week aerobic training program enhanced erythrocyte antioxidant status in heavy drinkers, indicating that aerobic training may attenuate pathological processes caused by alcohol-induced oxidative stress.This study was co-financed by the European Union [European Social Fund (ESF)] and Greek national funds through the Operational Program ‘Education and Lifelong Learning’ of the National Strategic Reference Framework-Research Funding Program: THALES. Investing in knowledge society through the ESF.Published versio
Afatinib versus erlotinib as second-line treatment of patients with advanced squamous cell carcinoma of the lung: Final analysis of the randomised phase 3 LUX-Lung 8 trial
Background: LUX-Lung 8 was a randomised, controlled, phase 3 study comparing afatinib and erlotinib as second-line treatment of patients with advanced squamous cell carcinoma (SCC) of the lung. We report the final overall survival (OS) and safety analyses of LUX-Lung 8 and investigate the characteristics of patients who achieved long-term benefit (≥12 months’ treatment). Methods: LUX-Lung 8 (NCT01523587) enroled patients between March 2012 and January 2014 in 183 cancer centres located in 23 countries worldwide and this final analysis had a data cut-off of March 2018. Eligible patients had stage IIIB or IV lung SCC and had progressed after at least four cycles of platinum-based chemotherapy. Patients were randomly assigned (1:1) to receive afatinib (40 mg per day) or erlotinib (150 mg per day) until disease progression. Endpoints included OS and safety; a post-hoc analysis of patients with long-term benefit (≥12 months on treatment) was also conducted. Findings: 795 eligible patients were randomly assigned (398 to afatinib, 397 to erlotinib). OS was significantly prolonged with afatinib compared with erlotinib (median 7·8 months vs 6·8 months; hazard ratio 0·84; 95% CI 0·73–0·97; p = 0·0193). These findings were consistent with those of the primary analysis and were consistent across subgroups. Adverse events (AEs) were manageable with dose interruption and reduction, with similar AEs being experienced between both groups. Twenty-one (5·3%) patients receiving afatinib and 13 (3·3%) patients receiving erlotinib achieved long-term benefit; median OS was 34·6 months and 20·1 months, respectively. Amongst 132 afatinib-treated patients who underwent tumour genetic analysis, ERBB family mutations were more common in patients with long-term benefit than in the overall population (50% vs 21%). Interpretation: Afatinib is a treatment option for patients with SCC of the lung progressing on chemotherapy who are ineligible for immunotherapy, particularly those with ERBB family genetic aberrations. Afatinib has a predictable and manageable tolerability profile, and long-term treatment may be well tolerated
Second-line treatment with irinotecan plus cisplatin vs cisplatin of patients with advanced non-small-cell lung cancer pretreated with taxanes and gemcitabine: a multicenter randomised phase II study
The aim of this study was to compare the irinotecan/cisplatin regimen with cisplatin as second-line chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) pretreated with a taxane/gemcitabine regimen. Patients (n=147) with stage IV NSCLC pretreated with a taxane/gemcitabine regimen were randomly assigned to receive either irinotecan (110 mg m−2, day 1 and 100 mg m−2, day 8) and cisplatin (80 mg m−2, day 8) (IC; n=74) or CDDP (80 mg m−2, day 1) (C; n=73) every 3 weeks. Patients treated with IC and C had a median survival of 7.8 and 8.8 months, respectively (P=0.933). The 1-year survival rate was 34.3% for IC-treated patients and 31.7% for C-treated patients. Cox's regression analysis revealed that response to treatment (hazard ratio (HR)=2.787; 95% confidence interval (CI): 1.1578–4.922) and performance status (HR=1.865; 95% CI: 1.199–2.872) was independent prognostic factors for survival. Overall response rate was 22.5% (95% CI: 12.8–32.2%) for IC-treated patients and 7.0% (95% CI: 1.15–13.6%) for C-treated patients (P=0.012); tumour growth control (partial remission (PR)+stable disease (SD)) was observed in 26 (38%) IC and 25 (36%) C patients (P=0.878). There was no difference in terms of quality of life between the two chemotherapy arms. The incidence of febrile neutropenia, grade 3 and 4 neutropenia and grade 3 and 4 diarrhoea was significantly higher in the IC- than the C-treated patients. Other toxicities were mild. There were no treatment-related deaths in either arm. The IC regimen did not confer a survival benefit compared with C as second-line treatment of patients with advanced NSCLC pretreated with a taxane/gemcitabine regimen, despite its better efficacy in terms of response rate
Secular trends of antimicrobial resistance of blood isolates in a newly founded Greek hospital
BACKGROUND: Antimicrobial resistance is one of the most challenging issues in modern medicine. METHODS: We evaluated the secular trends of the relative frequency of blood isolates and of the pattern of their in vitro antimicrobial susceptibility in our hospital during the last four and a half years. RESULTS: Overall, the data regarding the relative frequency of blood isolates in our newly founded hospital do not differ significantly from those of hospitals that are functioning for a much longer period of time. A noteworthy emerging problem is the increasing antimicrobial resistance of Gram-negative bacteria, mainly Acinetobacter baumannii and Klebsiella pneumoniae to various classes of antibiotics. Acinetobacter baumannii isolates showed an increase of resistance to amikacin (p = 0.019), ciprofloxacin (p = 0.001), imipenem (p < 0.001), and piperacillin/tazobactam (p = 0.01) between the first and second period of the study. CONCLUSION: An alarming increase of the antimicrobial resistance of Acinetobacter baumannii isolates has been noted during our study
Spatial and seasonal variations of aerosols over China from two decades of multi-satellite observations – Part 1: ATSR (1995–2011) and MODIS C6.1 (2000–2017)
Aerosol optical
depth (AOD) patterns and interannual and seasonal variations over China are
discussed based on the AOD retrieved from the Along-Track Scanning Radiometer
(ATSR-2, 1995–2002), the Advanced ATSR (AATSR, 2002–2012) (together ATSR) and
the MODerate resolution Imaging Spectroradiometer (MODIS) aboard the Terra
satellite (2000–2017). The AOD products used were the ATSR Dual View (ADV)
v2.31 AOD and the MODIS/Terra Collection 6.1 (C6.1) merged dark target (DT) and
deep blue (DB) AOD product. Together these datasets provide an AOD time
series for 23 years, from 1995 to 2017. The difference between the AOD values
retrieved from ATSR-2 and AATSR is small, as shown by pixel-by-pixel and
monthly aggregate comparisons as well as validation results. This allows for
the combination of the ATSR-2 and AATSR AOD time series into one dataset without offset
correction.ADV and MODIS AOD validation results show similar high correlations with the
Aerosol Robotic Network (AERONET) AOD (0.88 and 0.92, respectively), while
the corresponding bias is positive for MODIS (0.06) and negative for ADV
(−0.07). Validation of the AOD products in similar conditions, when ATSR and
MODIS/Terra overpasses are within 90 min of each other and when both
ADV and MODIS retrieve AOD around AERONET locations, show that ADV performs
better than MODIS in autumn, while MODIS performs slightly better in spring
and summer. In winter, both ADV and MODIS underestimate the AERONET AOD.Similar AOD patterns are observed by ADV and MODIS in annual and seasonal
aggregates as well as in time series. ADV–MODIS difference maps show that
MODIS AOD is generally higher than that from ADV. Both ADV and MODIS show
similar seasonal AOD behavior. The AOD maxima shift from spring in the south to summer along the eastern coast further north.The agreement between sensors regarding year-to-year AOD changes is quite good.
During the period from 1995 to 2006 AOD increased in the southeast (SE) of China. Between
2006 and 2011 AOD did not change much, showing minor minima in 2008–2009.
From 2011 onward AOD decreased in the SE of China. Similar patterns
exist in year-to-year ADV and MODIS annual AOD tendencies in the overlapping
period. However, regional differences between the ATSR and MODIS AODs are
quite large. The consistency between ATSR and MODIS with regards to the AOD
tendencies in the overlapping period is rather strong in summer, autumn and
overall for the yearly average; however, in winter and spring, when there is a
difference in coverage between the two instruments, the agreement between
ATSR and MODIS is lower.AOD tendencies in China during the 1995–2017 period will be discussed in more
detail in Part 2 (a following paper: Sogacheva et al., 2018), where a method to combine AOD time series from ADV and
MODIS is introduced, and combined AOD time series are analyzed.</p
Gemcitabine and vinorelbine followed by docetaxel in patients with advanced non-small-cell lung cancer: a multi-institutional phase II trial of nonplatinum sequential triplet combination chemotherapy (JMTO LC00-02)
To evaluate the efficacy and toxicity of the sequential nonplatinum combination chemotherapy consisting of gemcitabine (GEM) and vinorelbine (VNR) followed by docetaxel (DOC) in patients with advanced non-small-cell lung cancer (NSCLC), we conducted the multiinstitutional phase II study. A total of 44 chemotherapy-naive patients with advanced NSCLC were treated with GEM 1000 mg m−2 and VNR 25 mg m−2 intravenously on days 1 and 8 every 3 weeks for three cycles. DOC 60 mg m−2 was then administrated intravenously at 3-week intervals for three cycles. Patients were evaluated for response and toxicity with each cycle of the treatment. The major objective response rate was 47.7% (95% confidence interval (CI), 33.8–62.1%). Median survival time (MST) was 15.7 months and 1-year survival rate was 59%. In the GEM/VNR cycle, grade 3/4 neutropenia occurred in 36.3%, grade 3/4 anaemia in two patients (4.5%) and grade 3 thrombocytopenia in one patient (2.3%). Grade 3 pneumonitis occurred in two patients (4.5%) in GEM/VNR cycles. In the DOC cycles, grade 3/4 neutropenia occurred in 39.4% but no patient experienced grade 3/4 anaemia or thrombocytopenia. Of the 44 eligible patients, 33 patients completed three cycles of GEM/VNR and 22 patients completed six cycles of planned chemotherapy (three cycles of GEM/VNR followed by three cycles of DOC). The sequential triplet nonplatinum chemotherapy consisted of GEM/VNR followed by DOC, and was very active and well tolerated. This study forms the basis for an ongoing phase III trial that compares this nonplatinum triplet and standard platinum doublet combination (carboplatin/paclitaxel)
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