516 research outputs found

    Decoherence of Einstein-Podolsky-Rosen steering

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    We consider two systems A and B that share Einstein-Podolsky-Rosen (EPR) steering correlations and study how these correlations will decay, when each of the systems are independently coupled to a reservoir. EPR steering is a directional form of entanglement, and the measure of steering can change depending on whether the system A is steered by B, or vice versa. First, we examine the decay of the steering correlations of the two-mode squeezed state. We find that if the system B is coupled to a reservoir, then the decoherence of the steering of A by B is particularly marked, to the extent that there is a sudden death of steering after a finite time. We find a different directional effect, if the reservoirs are thermally excited. Second, we study the decoherence of the steering of a Schr\"odinger cat state, modeled as the entangled state of a spin and harmonic oscillator, when the macroscopic system (the cat) is coupled to a reservoir

    Impact of NOx vehicle emission standards failure on Air Quality in Europe

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    Vehicle exhaust emission standards have been tightened in the EU for several decades now, in order to protect health and the environment. This has led to a substantial decrease in total pollutant emissions, despite the growing volumes of passenger and freight transport. However, national emissions, particularly of NOx, exceed the ceilings accorded under the Gothenburg Protocol of the UNECE's Convention on Long-Range Transboundary Air Pollution (LRTAP) (EEA 2012) in twelve EU Member States. The main reasons for such exceedances are that more diesel cars have been sold than originally predicted when fixing the targets, and that diesel cars emit much more than expected under real-world driving conditions. The latter appears as a consequence of the effort to achieve high fuel efficiency. While this has largely helped to control CO2 emissions, it was to the detriment of NOx. In this study we estimate what the impact of the different vehicle emission standards has been so far and to predict what the impact of upcoming emission standards will be in the future, using the best current knowledge on road transport activity statistics and emission factors in Europe. We present several sensitivity calculations to reflect the considerable uncertainty about the real-driving NOx emissions of diesel light duty vehicles. The results of this work can be useful in designing both limits for upcoming standards but also in assessing the impact of deviating from such limits. This is necessary in both deciding on the next steps of emission control policy and to relevant air quality prediction models

    MatricS—A novel tool for monitoring professional role development in surgical disciplines

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    Introduction: Mentoring is an effective method for human resource development. Monitoring the process is important for individual mentee/mentor pairs as well as for program directors. Due to individual personality differences of both mentees and mentors and their respective interactions, it is challenging to monitor the individual development process of mentees in a structured manner. This study investigates to what extent a novel instrument, the mentee-based assessment tool for role development of interpersonal competencies in surgical professions (MatricS) can adequately monitor the professional role development process of residents during an established mentoring program. Material and methods: In a prospective longitudinal study, the competence development of 31 mentees in two subsequent cohorts was assessed by a modified role matrix based on Canadian Medical Education Directives for Specialists. The evaluation focused on three defined roles (D, developer; N, networker; M, multiplicator) at three levels (private, employer-related, national/international) with four stages of development. For validation of mentee self-assessments, the assessments of the respective mentors were recorded alongside. For correlation analyses, Pearson coefficients were calculated, pre-post-comparisons were done by paired t-tests; significance was assumed at p < 0.05, respectively. Results: Mentee self-assessments overall correlated well with the objective mentor assessments (Pearson's r 0.8, p 75% of all roles and levels. Conclusion: The role development process during mentoring can be reliably monitored by using MatricS. MatricS scores highly correlate between mentees and mentors, indicating that mentee self-assessments are suitable and sufficient for monitoring. These findings help to lessen the work burden on senior surgeons and thus can help to increase the acceptance of mentoring programs in surgical disciplines

    Urban versus rural health impacts attributable to PM2.5 and O3 in northern India

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    Ambient air pollution in India contributes to negative health impacts and early death. Ground-based monitors often used to quantify health impacts are located in urban regions, yet approximately 70% of India's population lives in rural communities. We simulate high-resolution concentrations of fine particulate matter (PM) and ozone from the regional Community Multi-scale Air Quality model over northern India, including updated estimates of anthropogenic emissions for transportation, residential combustion and location-based industrial and electrical generating emissions in a new anthropogenic emissions inventory. These simulations inform seasonal air quality and health impacts due to anthropogenic emissions, contrasting urban versus rural regions. For our northern India domain, we estimate 463 200 (95% confidence interval: 444 600–482 600) adults die prematurely each year from PM2.5 and that 37 800 (28 500–48 100) adults die prematurely each year from O3. This translates to 5.8 deaths per 10 000 attributable to air pollution out of an annual rate of 72 deaths per 10 000 (8.1% of deaths) using 2010 estimates. We estimate that the majority of premature deaths resulting from PM2.5 and O3 are in rural (383 600) as opposed to urban (117 200) regions, where we define urban as cities and towns with populations of at least 100 000 people. These findings indicate the need for rural monitoring and appropriate health studies to understand and mitigate the effects of ambient air pollution on this population in addition to supporting model evaluation

    Oligocarbonate Molecular Transporters: Oligomerization-Based Syntheses and Cell-Penetrating Studies

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    A new family of guanidinium-rich molecular transporters featuring a novel oligocarbonate backbone with 1,7-side chain spacing is described. Conjugates can be rapidly assembled irrespective of length in a one-step oligomerization strategy that can proceed with concomitant introduction of probes (or by analogy drugs). The new transporters exhibit excellent cellular entry as determined by flow cytometry and fluorescence microscopy, and the functionality of their drug delivery capabilities was confirmed by the delivery of the bioluminescent small molecule probe luciferin and turnover by its intracellular target enzyme

    Development of individual competencies and team performance in interprofessional ward rounds: results of a study with multimodal observations at the Heidelberg Interprofessional Training Ward.

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    INTRODUCTION Interprofessional training wards (IPTW) aim to improve undergraduates' interprofessional collaborative practice of care. Little is known about the effects of the different team tasks on IPTW as measured by external assessment. In Heidelberg, Germany, four nursing and four medical undergraduates (= one cohort) care for up to six patients undergoing general surgery during a four-week placement. They learn both professionally and interprofessionally, working largely on their own responsibility under the supervision of the medical and nursing learning facilitators. Interprofessional ward rounds are a central component of developing individual competencies and team performance. The aim of this study was to evaluate individual competencies and team performance shown in ward rounds. METHODS Observations took place in four cohorts of four nursing and four medical undergraduates each. Undergraduates in one cohort were divided into two teams, which rotated in morning and afternoon shifts. Team 1 was on morning shift during the first (t0) and third (t1) weeks of the IPTW placement, and Team 2 was on morning shift during the second (t0) and fourth (t1) weeks. Within each team, a tandem of one nursing and one medical undergraduate cared for a patient room with three patients. Ward round observations took place with each team and tandem at t0 and t1 using the IP-VITA instrument for individual competencies (16 items) and team performance (11 items). Four hypotheses were formulated for statistical testing with linear mixed models and correlations. RESULTS A total of 16 nursing and medical undergraduates each were included. There were significant changes in mean values between t0 and t1 in individual competencies (Hypothesis 1). They were statistically significant for all three sum scores: "Roles and Responsibilities", Patient-Centeredness", and "Leadership". In terms of team performance (Hypothesis 2), there was a statistically significant change in mean values in the sum score "Roles and Responsibilities" and positive trends in the sum scores "Patient-Centeredness" and "Decision-Making/Collaborative Clinical Reasoning". Analysis of differences in the development of individual competencies in the groups of nursing and medical undergraduates (Hypothesis 3) showed more significant differences in the mean values of the two groups in t0 than in t1. There were significant correlations between individual competencies and team performance at both t0 and t1 (Hypothesis 4). DISCUSSION The study has limitations due to the small sample and some sources of bias related to the external assessment by means of observation. Nevertheless, this study offers insights into interprofessional tasks on the IPTW from an external assessment. Results from quantitative and qualitative analysis of learners self-assessment are confirmed in terms of roles and responsibilities and patient-centeredness. It has been observed that medical undergraduates acquired and applied skills in collaborative clinic reasoning and decision-making, whereas nursing undergraduates acquired leadership skills. Within the study sample, only a small group of tandems remained constant over time. In team performance, the group of constant tandems tended to perform better than the group of random tandems. The aim of IPTW should be to prepare healthcare team members for the challenge of changing teams. Therefore, implications for IPTW implementation could be to develop learning support approaches that allow medical and nursing undergraduates to bring interprofessional competencies to team performance, independent of the tandem partner or team

    Designed Guanidinium-Rich Amphipathic Oligocarbonate Molecular Transporters Complex, Deliver and Release siRNA in Cells

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    The polyanionic nature of oligonucleotides and their enzymatic degradation present challenges for the use of siRNA in research and therapy; among the most notable of these is clinically relevant delivery into cells. To address this problem, we designed and synthesized the first members of a new class of guanidinium-rich amphipathic oligocarbonates that noncovalently complex, deliver, and release siRNA in cells, resulting in robust knockdown of target protein synthesis in vitro as determined using a dual-reporter system. The organocatalytic oligomerization used to synthesize these co-oligomers is step-economical and broadly tunable, affording an exceptionally quick strategy to explore chemical space for optimal siRNA delivery in varied applications. The speed and versatility of this approach and the biodegradability of the designed agents make this an attractive strategy for biological tool development, imaging, diagnostics, and therapeutic applications

    Mitigating ammonia emission from agriculture reduces PM2.5 pollution in the Hai River Basin in China

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    The Hai River Basin (HRB), one of the most populated areas in China, is experiencing high NH3 emissions, mostly from agricultural sources, and suffering from strongly enhanced PM2.5 concentrations in all urban areas. Further population growth and urbanization projected until 2030 may exacerbate this situation. Here, the NUFER (NUtrient flows in Food chains, Environment and Resources use) and GAINS (Greenhouse gas – Air pollution Interactions and Synergies) models have been coupled for the first time to understand possible changes of agricultural NH3 emission between 2012 and 2030 and their impacts on ambient PM2.5 concentrations, and to explore options to improve this situation. Results show that agricultural ammonia emissions in the HRB were 1179 kt NH3 in 2012, 45% of which was from the hotspots at or near conurbation areas, including Beijing-Tianjin, Tangshan-Qinhuangdao, Shijiazhuang-Baoding, Dezhou, Handan-Liaocheng, and Xinxiang. Without intervention, agricultural ammonia emissions will further increase by 33% by 2030. The impacts of several scenarios were tested with respect to air pollution. Compared to the business-as-usual scenario, a scenario of improved technology and management combined with human diet optimization could greatly reduce emission (by 60%), and lead to 22–43% and 9–24% decrease of the secondary inorganic aerosols and PM2.5 concentrations, respectively, in the hotspots of NH3 emissions. Our results further confirmed that ammonia control is needed for air pollution abatement strategies (SO2, NOx and primary PM reduction) to be effective in terms of PM2.5

    Air quality and health effects of a transition to ammonia–fueled shipping in Singapore

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    Ammonia has been proposed to replace heavy fuel oil (HFO) in the shipping industry by 2050. When produced with low-carbon electricity, ammonia can reduce greenhouse gas emissions. However, ammonia emissions also contribute to local air pollution via the formation of secondary particulate matter. We estimate the potential ammonia emissions from storage and bunkering operations for shipping in Singapore, a port that accounts for 20% of global bunker fuel sales, and their impacts on air quality and health. Fuel storage and bunkering can increase total gaseous ammonia emissions in Singapore by up to a factor of four and contribute to a 25%–50% increase in ambient PM2.5 concentration compared to a baseline scenario with HFO, leading to an estimated 210–460 premature mortalities in Singapore (30%–70% higher than the baseline). Proper abatement on storage and bunkering can reduce these emissions and even improve ambient PM2.5 concentrations compared to the baseline. Overall, while an energy transition from HFO to ammonia in the shipping industry could reduce global greenhouse gas and air pollutant burdens, local policies will be important to avoid negative impacts on the communities living near its supply chain

    Assessing the macroeconomic impacts of individual behavioral changes on carbon emissions

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    © 2019, The Author(s). In the last decade, instigated by the Paris agreement and United Nations Climate Change Conferences (COP22 and COP23), the efforts to limit temperature increase to 1.5 °C above pre-industrial levels are expanding. The required reductions in greenhouse gas emissions imply a massive decarbonization worldwide with much involvement of regions, cities, businesses, and individuals in addition to the commitments at the national levels. Improving end-use efficiency is emphasized in previous IPCC reports (IPCC 2014). Serving as the primary ‘agents of change’ in the transformative process towards green economies, households have a key role in global emission reduction. Individual actions, especially when amplified through social dynamics, shape green energy demand and affect investments in new energy technologies that collectively can curb regional and national emissions. However, most energy-economics models—usually based on equilibrium and optimization assumptions—have a very limited representation of household heterogeneity and treat households as purely rational economic actors. This paper illustrates how computational social science models can complement traditional models by addressing this limitation. We demonstrate the usefulness of behaviorally rich agent-based computational models by simulating various behavioral and climate scenarios for residential electricity demand and compare them with the business as usual (SSP2) scenario. Our results show that residential energy demand is strongly linked to personal and social norms. Empirical evidence from surveys reveals that social norms have an essential role in shaping personal norms. When assessing the cumulative impacts of these behavioral processes, we quantify individual and combined effects of social dynamics and of carbon pricing on individual energy efficiency and on the aggregated regional energy demand and emissions. The intensity of social interactions and learning plays an equally important role for the uptake of green technologies as economic considerations, and therefore in addition to carbon-price policies (top-down approach), implementing policies on education, social and cultural practices can significantly reduce residential carbon emissions
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