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Precipitating auroral and radiation belt electrons are considered to play an important part in the natural forcing of the middle atmosphere with a possible impact on the climate system. Recent studies suggest that this forcing is underestimated in current chemistry-climate models. The HEPPA III intercomparison experiment is a collective effort to address this point. In this study, we apply electron ionization rates from three data-sets in four chemistry-climate models during a geomagnetically active period in April 2010. Results are evaluated by comparison with observations of nitric oxide (NO) in the mesosphere and lower thermosphere. Differences between the ionization rate data-sets have been assessed in a companion study. In the lower thermosphere, NO densities differ by up to one order of magnitude between models using the same ionization rate data-sets due to differences in the treatment of NO formation, model climatology, and model top height. However, a good agreement in the spatial and temporal variability of NO with observations lends confidence that the electron ionization is represented well above 80 km. In the mesosphere, the averages of model results from all chemistry-climate models differ consistently with the differences in the ionization-rate data-sets, but are within the spread of the observations, so no clear assessment on their comparative validity can be provided. However, observed enhanced amounts of NO in the mid-mesosphere below 70 km suggest a relevant contribution of the high-energy tail of the electron distribution to the hemispheric NO budget during and after the geomagnetic storm on April 6. © 2021 The Authors.

Precipitating auroral and radiation belt electrons are considered to play an important part in the natural forcing of the middle atmosphere with a possible impact on the climate system. Recent studies suggest that this forcing is underestimated in current chemistry-climate models. The HEPPA III intercomparison experiment is a collective effort to address this point. In this study, we apply electron ionization rates from three data-sets in four chemistry-climate models during a geomagnetically active period in April 2010. Results are evaluated by comparison with observations of nitric oxide (NO) in the mesosphere and lower thermosphere. Differences between the ionization rate data-sets have been assessed in a companion study. In the lower thermosphere, NO densities differ by up to one order of magnitude between models using the same ionization rate data-sets due to differences in the treatment of NO formation, model climatology, and model top height. However, a good agreement in the spatial and temporal variability of NO with observations lends confidence that the electron ionization is represented well above 80 km. In the mesosphere, the averages of model results from all chemistry-climate models differ consistently with the differences in the ionization-rate data-sets, but are within the spread of the observations, so no clear assessment on their comparative validity can be provided. However, observed enhanced amounts of NO in the mid-mesosphere below 70 km suggest a relevant contribution of the high-energy tail of the electron distribution to the hemispheric NO budget during and after the geomagnetic storm on April 6.

The primary tumor side is emerging as a prognostic factor for patients with liver metastatic colorectal cancer (mCRC). In a combined analysis of data from 2 randomized studies, the addition of selective internal radiation therapy to first-line chemotherapy in patients with mCRC was associated with statistically and clinically significant overall survival gains for patients with a right-sided primary tumor. Background(s): The primary tumor side is emerging as a major prognostic factor for patients with metastatic colorectal cancer (mCRC). We examined the survival data from 2 randomized studies to determine whether the outcomes differ between patients with mCRC with right-sided primary (RSP) tumors and those with left-sided primary (LSP) tumors after selective internal radiation therapy (SIRT) plus mFOLFOX6 (folinic acid [leucovorin], 5-fluorouracil, oxaliplatin) chemotherapy, versus chemotherapy alone. Patients and Methods: Separate and combined analyses were performed on the data from the SIRFLOX and FOXFIRE global trials, which compared chemotherapy plus SIRT with chemotherapy alone for patients with mCRC liver metastases. The primary tumor side data were prospectively collected. The principal outcome measure was overall survival (OS) stratified by treatment and primary tumor side. Result(s): In the combined analysis of all 739 patients enrolled, SIRT had no effect on OS (median OS, 24.3 vs. 24.6 months; hazard ratio [HR], 1.021; P =.810). For the 179 patients (24.2%) with a RSP tumor, OS was improved with the addition of SIRT (median, 22.0 vs. 17.1 months HR, 0.641; P =.008). The addition of SIRT was not associated with a significant difference in OS among the 540 patients with a LSP tumor (median, 24.6 vs. 26.6 months; HR, 1.120; P =.264). A test of treatment interaction by primary tumor side was statistically significant for RSP and SIRT (P =.002). Conclusion(s): The addition of SIRT for patients with RSP tumors, but not for those with LSP tumors, was associated

Single-index models are popular regression models that are more flexible than linear models and still maintain more structure than purely nonparametric models. We consider the problem of estimating the regression parameters under a monotonicity constraint on the unknown link function. In contrast to the standard approach of using smoothing techniques, we review different "non-smooth" estimators that avoid the difficult smoothing parameter selection. For about 30 years, one has had the conjecture that the profile least squares estimator is an n-consistent estimator of the regression parameter, but the only non-smooth argmin/argmax estimators that are actually known to achieve this n-rate are not based on the nonparametric least squares estimator of the link function. However, solving a score equation corresponding to the least squares approach results in n-consistent estimators. We illustrate the good behavior of the score approach via simulations. The connection with the binary choice and current status linear regression models is also discussed., Statistics

We construct n-consistent and asymptotically normal estimates for the finite dimensional regression parameter in the current status linear regression model, which do not require any smoothing device and are based on maximum likelihood estimates (MLEs) of the infinite dimensional parameter. We also construct estimates, again only based on these MLEs, which are arbitrarily close to efficient estimates, if the generalized Fisher information is finite. This type of efficiency is also derived under minimal conditions for estimates based on smooth nonmonotone plug-in estimates of the distribution function. Algorithms for computing the estimates and for selecting the bandwidth of the smooth estimates with a bootstrap method are provided. The connection with results in the econometric literature is also pointed out., Statistics

Nitric oxide (NO) produced in the polar middle and upper atmosphere by energetic particle precipitation depletes ozone in the mesosphere and, following vertical transport in the winter polar vortex, in the stratosphere. Medium energy electron (MEE) ionization by 30–1000 keV electrons during geomagnetic storms may have a significant role in mesospheric NO production. However, questions remain about the relative importance of direct NO production by MEE at altitudes ~60–90 km versus indirect NO originating from auroral ionization above 90 km. We investigate potential drivers of NO variability in the southern‐hemisphere mesosphere and lower thermosphere during 2013–14. Contrasting geomagnetic activity occurred during the two austral winters, with more numerous moderate storms in the 2013 winter. Ground‐based millimeter‐wave observations of NO from Halley, Antarctica are compared with measurements by the Solar Occultation For Ice Experiment (SOFIE) space‐borne spectrometer. NO partial columns over the altitude range 65–140 km from the two observational datasets show large day to day variability and significant disagreement, with Halley values on average 49% higher than the corresponding SOFIE data. SOFIE NO number densities, zonally averaged over geomagnetic latitudes ‐59°to ‐65°, are up to 3×108 cm‐3 higher in the winter of 2013 compared to 2014. Comparisons with a new version of the Whole Atmosphere Community Climate Model, which includes detailed D‐region ion chemistry (WACCM‐SIC) and MEE ionization rates, show that the model underestimates NO in the winter lower mesosphere whereas thermospheric abundances are too high. This indicates the need to further improve and verify WACCM‐SIC with respect to MEE ionization, thermospheric NO chemistry, and vertical transport.

It has been proved that direct bootstrapping of the nonparametric maximum likelihood estimator (MLE) of the distribution function in the current status model leads to inconsistent confidence intervals. We show that bootstrapping of functionals of the MLE can however be used to produce valid intervals. To this end, we prove that the bootstrapped MLE converges at the right rate in the L p Lp -distance. We also discuss applications of this result to the current status regression model., Statistics

This article explores the merits of foregrounding the dichotomy of politicization vs de-politicization for our understanding of bio-objects in order to study their production,circulation, and governance in European societies.By asking how bio-objects are configured in science, policy, public,and media discourses and practices,we focus on the role ofsocio-technical configurations in generating political relations. The bio-object thereby serves as an entry point to approach and conceptualize>the political>in an innovative way.Drawing from our previous work, which uses the concepts of de-politicization and (re-)politicization, this paper puts forward a research agenda for studying the political relations generated by specific socio-technical configurations of bio-objects.

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