Moments of nonclassicality quasiprobabilities

A method is introduced for the verification of nonclassicality in terms of moments of nonclassicality quasiprobability distributions. The latter are easily obtained from experimental data and will be denoted as nonclassicality moments. Their relation to normally-ordered moments is derived, which enables us to verify nonclassicality by using well established criteria. Alternatively, nonclassicality criteria are directly formulated in terms of nonclassicality moments. The latter converge in proper limits to the usually used criteria, as is illustrated for squeezing and sub-Poissonian photon statistics. Our theory also yields expectation values of any observable in terms of nonclassicality moments.Comment: 6 pages, 3 figure

Das "System Putin" - Die Schwächen des starken Staates

Russland steht vor tiefgreifenden Veränderungen. Positive makroökonomische Daten können nicht darüber hinwegtäuschen, dass Wirtschaft und Gesellschaft mit schwer zu lösenden Problemen konfrontiert sind. Der Erfolg wird abhängen vom Willen und der Fähigkeit der Führung, dem Bekenntnis zu einer marktwirtschaftlich-demokratischen Ordnung dauerhaft die notwendigen Taten folgen zu lassen

Das "System Putin" - Die Schwächen des starken Staates

Russland steht vor tiefgreifenden Veränderungen. Positive makroökonomische Daten können nicht darüber hinwegtäuschen, dass Wirtschaft und Gesellschaft mit schwer zu lösenden Problemen konfrontiert sind. Der Erfolg wird abhängen vom Willen und der Fähigkeit der Führung, dem Bekenntnis zu einer marktwirtschaftlich-demokratischen Ordnung dauerhaft die notwendigen Taten folgen zu lassen

Cross-Linguistic Twitter Analysis of Discussion Themes before, during and after Ramadan

© 2019 IEEE. This study represents the first comprehensive analysis of Twitter data for the United Arab Emirates using both Arabic and English texts. Particular attention is given to the impact of the holy period of Ramadan on the thematic content of Twitter discourse. We examine users\u27 tweet frequency, tweet length and tweet content for different languages (English/Arabic) using statistical methods and topic modeling. The results indicate that Arabic language tweets, during the Ramadan period, included more religious themes than did English tweets. Also, relative to English, Arabic tweets showed greater consistency of content during the three months of the study (before, during and after Ramadan). English content varied significantly over the three months with notable fluctuations in the frequency of content centering on the music, shopping, and health categories. These results suggest that such analytic methods applied to social media data can provide a useful indicator of societal discussion themes. Further research is merited with larger datasets over longer timeframes

Tibiofemoral and patellofemoral joint 3D-kinematics in patients with posterior cruciate ligament deficiency compared to healthy volunteers

Background: The posterior cruciate ligament (PCL) plays an important role in maintaining physiological kinematics and function of the knee joint. To date mainly in-vitro models or combined magnetic resonance and fluoroscopic systems have been used for quantifying the importance of the PCL. We hypothesized, that both tibiofemoral and patellofemoral kinematic patterns are changed in PCL-deficient knees, which is increased by isometric muscle flexion. Therefore the aim of this study was to simultaneously investigate tibiofemoral and patellofemoral 3D kinematics in patients suffering from PCL deficiency during different knee flexion angles and under neuromuscular activation. Methods: We enrolled 12 patients with isolated PCL-insufficiency as well as 20 healthy volunteers. Sagittal MR-images of the knee joint were acquired in different positions of the knee joint (0[degree sign], 30[degree sign], 90[degree sign] flexion, with and without flexing isometric muscle activity) on a 0.2 Tesla open MR-scanner. After segmentation of the patella, femur and tibia local coordinate systems were established to define the spatial position of these structures in relation to each other. Results: At full extension and 30[degree sign] flexion no significant difference was observed in PCL-deficient knee joints neither for tibiofemoral nor for patellofemoral kinematics. At 90[degree sign] flexion the femur of PCL-deficient patients was positioned significantly more anteriorly in relation to the tibia and both, the patellar tilt and the patellar shift to the lateral side, significantly increased compared to healthy knee joints. While no significant effect of isometric flexing muscle activity was observed in healthy individuals, in PCL-deficient knee joints an increased paradoxical anterior translation of the femur was observed at 90[degree sign] flexion compared to the status of muscle relaxation. Conclusions: Significant changes in tibiofemoral and patellofemoral joint kinematics occur in patients with isolated PCL-insufficiency above 30 degrees of flexion compared to healthy volunteers. Since this could be one reasonable mechanism in the development of OA our results might help to understand the long-term development of tibiofemoral and/or patellofemoral osteoarthritis in PCL-insufficient knee joints

"AI enhances our performance, I have no doubt this one will do the same": The Placebo effect is robust to negative descriptions of AI

Heightened AI expectations facilitate performance in human-AI interactions through placebo effects. While lowering expectations to control for placebo effects is advisable, overly negative expectations could induce nocebo effects. In a letter discrimination task, we informed participants that an AI would either increase or decrease their performance by adapting the interface, but in reality, no AI was present in any condition. A Bayesian analysis showed that participants had high expectations and performed descriptively better irrespective of the AI description when a sham-AI was present. Using cognitive modeling, we could trace this advantage back to participants gathering more information. A replication study verified that negative AI descriptions do not alter expectations, suggesting that performance expectations with AI are biased and robust to negative verbal descriptions. We discuss the impact of user expectations on AI interactions and evaluation and provide a behavioral placebo marker for human-AI interactio

Strengthening Uganda's policy environment for investing in university development

The authors examine the policy environment for investment in university development in Uganda, with special attention to the needs of Makerere University. They present data on the structure and financing of higher education, which gets a high priority in government educational spending. A second public university and new private universities have been established since 1986, but Makerere accounts for most university enrollment and government spending on higher education and it trains most of the country's high-level professional and technical manpower. Its revitalization after many years of neglect is central to government and donor plans for investment in human resource development. The authors emphasize how continuing austerity affects staff retention and staff engagement in academic work, as well as the quality of programs Makerere offers. They present a strategy for university development that involves establishing policy structures to: guide and coordinate investments in higher education as a whole; facilitate the expansion of higher education and the development of diploma-granting institutions to accommodate increasing social demand; and promote cost-saving and revenue-generating activities in the public universities - which would require giving them more autonomy in matters affecting their cost structure and budgeting. Among specific actions they recommend: making better use of public university assets by developing night courses, part-time degree and non-degree programs, and contract training and other income-generating activities; investigating possibilities for better use of university farms and other properties; making more use of existing capacity in public institutions and increasing the capacity of the newly established private universities; strengthening secondary education in science subjects and encouraging more women to study science and technology; coordinating future donor investments so they address the broad needs of Makerere and other universities; and raising incomes of academic and nonacademic university staff members.Teaching and Learning,Curriculum&Instruction,Gender and Education,Tertiary Education,Primary Education

Molecular Seesaw: How Increased Hydrogen Bonding Can Hinder Excited-State Proton Transfer

A previously unexplained effect in the relative rate of excited-state intramolecular proton transfer (ESIPT) in related indole derivatives is investigated using both theory and experiment. Ultrafast spectroscopy [J. Phys. Chem. A, 2015, 119, 5618–5625] found that although the diol 1,3-bis(2-pyridylimino)-4,7-dihydroxyisoindole exhibits two equivalent intramolecular hydrogen bonds, the ESIPT rate associated with tautomerization of either hydrogen bond is a factor of 2 slower than that of the single intramolecular hydrogen bond in the ethoxy-ol 1,3-bis(2-pyridylimino)-4-ethoxy-7-hydroxyisoindole. Excited-state electronic structure calculations suggest a resolution to this puzzle by revealing a seesaw effect in which the two hydrogen bonds of the diol are both longer than the single hydrogen bond in the ethoxy-ol. Semiclassical rate theory recovers the previously unexplained trends and leads to clear predictions regarding the relative H/D kinetic isotope effect (KIE) for ESIPT in the two systems. The theoretical KIE predictions are tested using ultrafast spectroscopy, confirming the seesaw effect

Arabia Felix 2.0: a cross-linguistic Twitter analysis of happiness patterns in the United Arab Emirates

© 2019, The Author(s). The global popularity of social media platforms has given rise to unprecedented amounts of data, much of which reflects the thoughts, opinions and affective states of individual users. Systematic explorations of these large datasets can yield valuable information about a variety of psychological and sociocultural variables. The global nature of these platforms makes it important to extend this type of exploration across cultures and languages as each situation is likely to present unique methodological challenges and yield findings particular to the specific sociocultural context. To date, very few studies exploring large social media datasets have focused on the Arab world. This study examined social media use in Arabic and English across the United Arab Emirates (UAE), looking specifically at indicators of subjective wellbeing (happiness) across both languages. A large social media dataset, spanning 2013 to 2017, was extracted from Twitter. More than 17 million Twitter messages (tweets), written in Arabic and English and posted by users based in the UAE, were analyzed. Numerous differences were observed between individuals posting messages (tweeting) in English compared with those posting in Arabic. These differences included significant variations in the mean number of tweets posted, and the mean size of users networks (e.g. the number of followers). Additionally, using lexicon-based sentiment analytic tools (Hedonometer and Valence Shift Word Graphs), temporal patterns of happiness (expressions of positive sentiment) were explored in both languages across all seven regions (Emirates) of the UAE. Findings indicate that 7:00 am was the happiest hour, and Friday was the happiest day for both languages (the least happy day varied by language). The happiest months differed based on language, and there were also significant variations in sentiment patterns, peaks and troughs in happiness, associated with events of sociopolitical and religio-cultural significance for the UAE

Non-equilibrium dynamics from RPMD and CMD

We investigate the calculation of approximate non-equilibrium quantum time correlation functions (TCFs) using two popular path-integral-based molecular dynamics methods, ring-polymer molecular dynamics (RPMD) and centroid molecular dynamics (CMD). It is shown that for the cases of a sudden vertical excitation and an initial momentum impulse, both RPMD and CMD yield non-equilibrium TCFs for linear operators that are exact for high temperatures, in the t = 0 limit, and for harmonic potentials; the subset of these conditions that are preserved for non-equilibrium TCFs of non-linear operators is also discussed. Furthermore, it is shown that for these non-equilibrium initial conditions, both methods retain the connection to Matsubara dynamics that has previously been established for equilibrium initial conditions. Comparison of non-equilibrium TCFs from RPMD and CMD to Matsubara dynamics at short times reveals the orders in time to which the methods agree. Specifically, for the position-autocorrelation function associated with sudden vertical excitation, RPMD and CMD agree with Matsubara dynamics up to O(t^4) and O(t^1), respectively; for the position-autocorrelation function associated with an initial momentum impulse, RPMD and CMD agree with Matsubara dynamics up to O(t^5) and O(t^2), respectively. Numerical tests using model potentials for a wide range of non-equilibrium initial conditions show that RPMD and CMD yield non-equilibrium TCFs with an accuracy that is comparable to that for equilibrium TCFs. RPMD is also used to investigate excited-state proton transfer in a system-bath model, and it is compared to numerically exact calculations performed using a recently developed version of the Liouville space hierarchical equation of motion approach; again, similar accuracy is observed for non-equilibrium and equilibrium initial conditions