The isotopic composition of methane in the stratosphere : high-altitude balloon sample measurements

The isotopic composition of stratospheric methane has been determined on a large suite of air samples from stratospheric balloon flights covering subtropical to polar latitudes and a time period of 16 yr. 154 samples were analyzed for δC and 119 samples for δD, increasing the previously published dataset for balloon borne samples by an order of magnitude, and more than doubling the total available stratospheric data (including aircraft samples) published to date. The samples also cover a large range in mixing ratio from tropospheric values near 1800 ppb down to only 250 ppb, and the strong isotope fractionation processes accordingly increase the isotopic composition up to δ13C=−14‰ and δD= +190‰, the largest enrichments observed for atmospheric CH4 so far. When analyzing and comparing kinetic isotope effects (KIEs) derived from single balloon profiles, it is necessary to take into account the residence time in the stratosphere in combination with the observed mixing ratio and isotope trends in the troposphere, and the range of isotope values covered by the individual profile. Temporal isotope trends can also be determined in the stratosphere and compare reasonably well with the tropospheric trends. The effects of chemical and dynamical processes on the isotopic composition of CH4 in the stratosphere are discussed in detail. Different ways to interpret the data in terms of the relative fractions of the three important sink mechanisms (reaction with OH, O(1D)) and Cl, respectively), and their limitations, are investigated. The classical approach of using global mean KIE values can be strongly biased when profiles with different minimum mixing ratios are compared. Approaches for more local KIE investigations are suggested. It is shown that any approach for a formal sink partitioning from the measured data severely underestimates the fraction removed by OH, which is likely due to the insensitivity of the measurements to the kinetic fractionation in the lower stratosphere. Attempts can be made to correct for the lower stratospheric sink bias, but full quantitative interpretation of the CH4 isotope data in terms of the three sink reactions requires a global model

Trust in the Sharing Economy: An Experimental Framework

Peer-to-peer platforms in the realm of the sharing economy, such as Airbnb or BlaBlaCar, have heavily rattled the electronic commerce landscape and are expected to further impact consumer behavior in the future. While trust between the parties involved is of utmost importance in such platform economies, experimental research on this aspect is scarce. In this conceptual paper, we first present an experimental framework for targeting trust in the sharing economy based on experimental economics and the trust game in particular. In doing so, we sketch out a path to complement existing Information Systems research on the sharing economy by experimental methods. Second, we apply the framework to a specific use case, by developing a research model and experimental design to explore the role of user representation for trust on sharing economy platforms. We therefore set the stage for controlled (laboratory) experiments to enrich research on trust in the sharing economy

Динамика фрикционных процессов при трении нержавеющей стали аустенитного класса 12Х18Н10Т с ультрамелкозернистой структурой

В работе рассматривается экспериментальное исследование динамики фрикционных процессов при трении объемных ультрамелкозернистых материалов. В качестве модельных образцов использовалась нержавеющая сталь аустенитного класса 12Х18Н10Т с ультрамелкозернистой структурой, сформированной методами ABC прессования и прокатки. В процессе сухого трения скольжения осуществлялась регистрация сигналов виброускорений и акустической эмиссии

Estimation of field production profiles in case of asphaltene deposition

In this work, we aimed to predict possible field production scenarios in case of asphaltene deposition based on field data as well as recommend remediation and stimulation measures to mitigate the risks of asphaltene deposition in the reservoir. We considered the influence of asphaltene formation in the near-wellbore of producers on the production data without reservoir pressure maintenance system in one of the oil fields. The asphaltene envelope in the reservoir oil was obtained, and the operating conditions of the field were evaluated under the possibility of asphaltene deposition. According to the results of dynamic modeling, the pressure map was plotted and the low-pressure areas in the near-wellbore were shown, which contributes to the aggravation of the problem associated with the asphaltene envelope. Based on the geometrical features of the low-pressure area, the dependence of the permeability reduction in the near-wellbore of the production well on the operating time was obtained using the asphaltene deposition model proposed by Wang and Civan. Based on the Buckley-Leverett theory, the field production profiles were calculated with and without asphaltene deposition. A decrease in the oil rate and consequently, the decrease in cumulative oil production in the field is expected due to the damage formation by solids. Maintenance of the production level will be facilitated by treating the nearwellbore with aromatic solvents and maintaining the reservoir pressure above the asphaltene onset pressure

Комплекс мероприятий по повышению противопожарной безопасности в образовательных учреждениях

В статье рассматривается весь комплекс организационных и планирующих мероприятий по проведению пожарной защиты в образовательных учреждениях России. порядок работы руководителей образовательных организаций по обеспечению безопасной жизнедеятельности учащихся и персонала.The article considers the whole complex of organizational and planning measures for conducting fire protection in educational institutions of Russia. the order of work of heads of educational organizations to ensure the safe functioning of students and staff

Совершенствование системы мотивации персонала на примере Общества с ограниченной ответственностью "Томторг" г. Томск

Объектом исследования является (ются)- предприятие малого бизнеса ООО "ТомТорг" Цель работы – рассмотреть систему мотивации персонала в ООО "ТомТорг" г.Томск и предложить рекомендации по ее совершенствованию. В процессе исследования проводились опрос и анкетирование. В результате исследования были разработаны несколько рекомендаций и мероприятий для совершенствования системы мотивации. Степень внедрения: Разработанные мероприятия внедрены и используются в деятельности ООО "ТомТорг" Область применения: разработанные мероприятия для мотивации персонала могут быть использованы на предприятии, в организации, фирме любой отрасли. Экономическая эффективность/значимость работы: эффективности и обоснованность разработанных рекомендаций экономически подтверждена.The object of the study is (are) - small business enterprise of LLC TomTorg The purpose of the work is to consider the system of staff motivation in TomTorg LLC in Tomsk and offer recommendations for its improvement. During the survey, a survey and questionnaire were conducted. As a result of the research, several recommendations and activities were developed to improve the motivation system. Degree of implementation: The developed measures are implemented and used in the activities of LLC TomTorg Scope: the developed measures for the motivation of personnel can be used at the enterprise, in the organization, in the firm of any industry. Economic efficiency / significance of the work: effectiveness and validity of the developed recommendations are economically confirmed

Impact of age and comorbidities on health-related quality of life for patients with prostate cancer: evaluation before a curative treatment

<p>Abstract</p> <p>Background</p> <p>Interpretation of comparative health-related quality of life (HRQOL) studies following different prostate cancer treatments is often difficult due to differing patient ages. Furthermore, age-related changes can hardly be discriminated from therapy-related changes. The evaluation of age-and comorbidity-related changes was in focus of this study.</p> <p>Methods</p> <p>HRQOL of 528 prostate cancer patients was analysed using a validated questionnaire (Expanded Prostate Cancer Index Composite) before a curative treatment. Patients were divided into age groups ≤65, 6670, 7175 and >75 years. The impact of specific comorbidities and the Charlson Comorbidity Index (CCI) were evaluated. The questionnaire comprises 50 items concerning the urinary, bowel, sexual and hormonal domains for function and bother. For assessment of sexual and hormonal domains, only patients without prior hormonal treatment were included (n = 336).</p> <p>Results</p> <p>Urinary incontinence was observed increasingly with higher age (mean function scores of 92/88/85/87 for patients ≤65, 6670, 7175 and >75 years) complete urinary control in 78%/72%/64%/58% (p < 0.01). Sexual function scores decreased particularly (48/43/35/30), with erections sufficient for intercourse in 68%/50%/36%/32% (p < 0.01) a decrease of more than a third comparing patients ≤65 vs. 6670 (36%) and 6670 vs. 7175 years (39%). The percentage of patients with comorbidities was lowest in the youngest group (48% vs. 66%/68%/63% for ages 6670/7175/>75 years; p < 0.05). A multivariate analysis revealed an independent influence of both age and comorbidities on urinary incontinence, specifically diabetes on urinary bother, and both age and diabetes on sexual function/bother. Rectal domain scores were not significantly influenced by age or comorbidities. A CCI>5 particularly predisposed for lower urinary and sexual HRQOL scores.</p> <p>Conclusion</p> <p>Urinary continence and sexual function are the crucial HRQOL domains with age-related and independently comorbidity-related decreasing scores. The results need to be considered for the interpretation of comparative studies or longitudinal changes after a curative treatment.</p

Geological calibration of spallation production rates in the CRONUS-Earth project

Models of the production of cosmogenic nuclides typically incorporate an adjustable production rate parameter that is scaled for variations in production with latitude and altitude. In practice, this production rate parameter is set by calibration of the model using cosmogenic nuclide data from sites with independent age constraints. In this paper, we describe a calibration procedure developed during the Cosmic-Ray Produced Nuclide Systematics on Earth (CRONUS-Earth) project and its application to an extensive data set that included both new CRONUS-Earth samples and samples from previously published studies. We considered seven frameworks for elevation and latitude scaling and five commonly used cosmogenic nuclides, 3He, 10Be, 14C, 26Al, and 36Cl. In general, the results show that the calibrated production rates fail statistical tests of goodness-of-fit. One conclusion from the calibration results is that two newly developed scaling frameworks and the widely used Lal scaling framework provide qualitatively similar fits to the data, while neutron-monitor based scaling frameworks have much poorer fit to the data. To further test the fitted models, we computed site ages for a number of secondary sites not included in the primary calibration data set. The root-mean-square percent differences between the median computed ages for these secondary sites and independent ages range from 7.1% to 27.1%, differences that are much larger than the typical uncertainties in the site ages. The results indicate that there are substantial unresolved difficulties in modeling cosmogenic nuclide production and the calibration of production rates