Distribution of the number of particles in the final state of hadron-nucleus collisions

Recently, Liou, Mueller and Munier have argued that proton-nucleus collisions at the LHC may give access to the full statistics of the event-by-event fluctuations of the gluon density in the proton. Indeed, the number of particles produced in an event in rapidity slices in the fragmentation region of the proton may, under some well-defined assumptions, be directly related to the number of gluons which have a transverse momentum larger than the nuclear saturation scale present in the proton at the time of the interaction with the nucleus. A first calculation of the probability distribution of the number of gluons in a hadron was performed, using the color dipole model. In this talk, we review this proposal, and present preliminary numerical calculations which support the analytical results obtained so far.Comment: 6 pages, 2 figures. Talk presented at DIS 201

Momentum average approximation for models with electron-phonon coupling dependent on the phonon momentum

We generalize the momentum average (MA) approximation to study the properties of models with momentum-dependent electron-phonon coupling. As in the case of the application of the original MA to the Holstein model, the results are analytical, numerically trivial to evaluate, exact for both zero bandwidth and for zero electron-phonon coupling, and are accurate everywhere in parameter space. Comparison with available numerical data confirms this accuracy. We then show that further improvements can be obtained based on variational considerations, using the one-dimensional breathing-mode Hamiltonian as a specific example. For example, by using this variational MA, we obtain ground state energies within at most 0.3% error of the numerical data.Comment: 15 pages, 10 figure

Mining for Signals of Future Consumer Expenditure on Twitter and Google Trends

Consumer expenditure constitutes the largest component of Gross Domestic Product in developed countries, and forecasts of consumer spending are therefore an important tool that governments and central bank use in their policy-making. In this paper we examine methods to forecast consumer spending from user-generated content, such as search engine queries and social media data, which hold the promise to produce forecasts much more efficiently than traditional surveys. Specifically, the aim of the paper is to study the relative utility of evidence about purchase intentions found in Google Trends versus those found in Twitter posts, for the problem of forecasting consumer expenditure. Our main findings are that, firstly, the Google Trends indicators and indicators extracted from Twitter are both beneficial for the forecasts: adding them as exogenous variables into regression model produces improvements on the pure AR baseline, consistently across all the forecast horizons. Secondly, we find that the Google Trends variables seem to be more useful predictors than the semantic variables extracted from Twitter posts, the differences in performance are significant, but not very large

Purchase Intentions on Social Media as Predictors of Consumer Spending

The paper addresses the problem of forecasting consumer expenditure from social media data. Previous research of the topic exploited the intuition that search engine traffic reflects purchase intentions and constructed predictive models of consumer behaviour from search query volumes. In contrast, we derive predictors from explicit expressions of purchase intentions found in social media posts. Two types of predictors created from these expressions are explored: those based on word embeddings and those based on topical word clusters. We introduce a new clustering method, which takes into account temporal co-occurrence of words, in addition to their semantic similarity, in order to create predictors relevant to the forecasting problem. The predictors are evaluated against baselines that use only macroeconomic variables, and against models trained on search traffic data. Conducting experiments with three different regression methods on Facebook and Twitter data, we find that both word embeddings and word clusters help to reduce forecasting errors in comparison to purely macroeconomic models. In most experimental settings, the error reduction is statistically significant, and is comparable to error reduction achieved with search traffic variables

Припиняючі способи цивільно - правового захисту прав на засоби індивідуалізації від недобросовісної конкуренції: цивільно-правове обґрунтування

The article presents an analysis of the concept and methods of civil protection of rights to the means of individualization. The study provided grounds to identify common features of liability and protection measures: aimed at their impact on the offender; aim to protect the rights and interests of the victim; can be implemented both voluntarily and compulsorily; directly enshrined in law; have a retrospective character; can be used alone or in combination. Distinctive features are also available. The following criteria are defined: the first criterion is the presence of non-equivalent property deprivations in civil liability; the second criterion: invariability of protection measures and variability of liability measures; the third criterion is the temporal (temporal) criterion; the fourth criterion for distinguishing between liability and protection measures are the forms of their implementation. Thus, the study provides grounds to identify common features of liability and protection measures: aimed at their impact on the offender; aimed at protecting the rights and interests of the victim. The study provided grounds to identify common features of liability and protection measures: aimed at their impact on the offender; aim to protect the rights and interests of the victim; can be implemented both voluntarily and compulsorily; directly enshrined in law; have a retrospective character; can be used alone or in combination. Distinctive features are also available. The following criteria are defined: the first criterion is the presence of non-equivalent property deprivation in civil liability; the second criterion: invariability of protection measures and variability of liability measures; the third criterion is the temporal (temporal) criterion; the fourth criterion for distinguishing between liability and protection measures are the forms of their implementation. Thus, the study provides grounds to identify common features of liability and protection measures: aimed at their impact on the offender; aimed at protecting the rights and interests of the victim.Key words: civil - legal protection of rights; means of individualization; intellectual property; unfair competition; measures of responsibility and protection.У статті представлено аналіз поняття і способи цивільно - правового захисту прав на засоби індивідуалізації. Проведене дослідження дало підстави виділити спільні риси заходів відповідальності і заходів захисту: спрямовані за своїм впливом на правопорушника; мають на меті захист прав та інтересів потерпілого; можуть бути реалізовані як в добровільному порядку, так і примусовому; прямо закріплені в законодавстві; мають ретроспективний характер; можуть використовуватися як поодинці, так і у сукупності. Відмінні риси також наявні. Визначено наступні критерії: першим критерієм є наявність при цивільно-правовій відповідальності позаеквівалентних майнових позбавлень; другий критерій: незмінюваність заходів захисту і змінюваність заходів відповідальності; третій критерієм є часовий (темпоральний) критерій; четвертим критерієм для розмежування заходів відповідальності і заходів захисту є форми їх реалізації. Отже, проведене дослідження дає підстави виділити спільні риси заходів відповідальності і заходів захисту: спрямовані за своїм впливом на правопорушника; мають на меті захист прав та інтересів потерпілого.Ключові слова: цивільно - правовий захист прав; засоби індивідуалізації; інтелектуальна власніть; недобросовісна конкуренція; заходи відповідальності і захисту.

Quantum nanostructures in strongly spin-orbit coupled two-dimensional systems

Recent progress in experimental studies of low-dimensional systems with strong spin-orbit coupling poses a question on the effect of this coupling on the energy spectrum of electrons in semiconductor nanostructures. It is shown in the paper that this effect is profound in the strong coupling limit. In circular quantum dots a soft mode develops, in strongly elongated dots electron spin becomes protected from the effects of the environment, and the lower branch of the energy spectrum of quantum wires becomes nearly flat in a wide region of the momentum space.Comment: 5 pages, 1 figur

Weak and strong coupling limits of the two-dimensional Fr\"ohlich polaron with spin-orbit Rashba interaction

The continuous progress in fabricating low-dimensional systems with large spin-orbit couplings has reached a point in which nowadays materials may display spin-orbit splitting energies ranging from a few to hundreds of meV. This situation calls for a better understanding of the interplay between the spin-orbit coupling and other interactions ubiquitously present in solids, in particular when the spin-orbit splitting is comparable in magnitude with characteristic energy scales such as the Fermi energy and the phonon frequency. In this article, the two-dimensional Fr\"ohlich electron-phonon problem is reformulated by introducing the coupling to a spin-orbit Rashba potential, allowing for a description of the spin-orbit effects on the electron-phonon interaction. The ground state of the resulting Fr\"ohlich-Rashba polaron is studied in the weak and strong coupling limits of the electron-phonon interaction for arbitrary values of the spin-orbit splitting. The weak coupling case is studied within the Rayleigh-Schr\"odinger perturbation theory, while the strong-coupling electron-phonon regime is investigated by means of variational polaron wave functions in the adiabatic limit. It is found that, for both weak and strong coupling polarons, the ground state energy is systematically lowered by the spin-orbit interaction, indicating that the polaronic character is strengthened by the Rashba coupling. It is also shown that, consistently with the lowering of the ground state, the polaron effective mass is enhanced compared to the zero spin-orbit limit. Finally, it is argued that the crossover between weakly and strongly coupled polarons can be shifted by the spin-orbit interaction.Comment: 11 pages, 5 figure

The use of pictures and videos showing dermal and mucosal symptoms by patients in medical practice

Introduction. Diagnostic imaging is an extremely important step towards making the final diagnosis of many diseases. Among the criteria of numerous diseases are cutaneous or mucosal changes, which occur paroxysmal and persist for a short time. Currently, patients are increasingly using technological progress and they document such changes with the help of mobile phone cameras. Purpose of work. The aim of the study was to determine whether patients turn to doctors with photographs or videos documenting their symptoms and whether it is useful in making the final diagnosis. Material and methods. The research method was a questionnaire constructed by authors of the article, which was answered by 107 doctors employees of the Medical University of Lublin and the Medical University of Bialystok. Participation in the study was voluntary and anonymous. Results. 75 (70%) of the respondents admitted that the patients brought them photos and videos documenting their symptoms. 73 (68%) of respondents considered them useful in making final diagnosis of diseases. Pictures and videos of head were shown to the doctors by 39 (36%) patients, pictures of neck by 30 (28%), pictures of upper limb by 37 (34%), pictures of lower limb by 39 (36%), pictures of chest by 38 (35%), pictures of stomach by 26 (24%) patients , pictures of pelvis by 26 (24%) patients, pictures of the back by 12 (11%), pictures of nails by 7 (6.5%), pictures of hair by 5 (4.6%) and pictures of eyes by 7 (6.5%) patients. Conclusions. Documenting short lasting dermal and mucosal symptoms by patients in the form of self photographs or films is a new tool that can help doctors in finding the right diagnosis

Phosphoproteomic studies of smooth muscle contraction: investigation of differential phosphorylation in relaxed/contracted rat aortic smooth muscle tissue using MALDI-TOF MS

Many human disorders are associated with the malfunction of smooth muscle tissue, or are related to the capabilities of its proper function—asthma, glaucoma, renal inefficiency, hypertension, and cardiovascular disease. Dysfunctional proteins are frequently implicated as the source of such disorders. As the second highest cause of death in the United States, the epidemic of cardiovascular disease makes the study of smooth muscle of utmost concern. The capabilities of proteomics and mass spectrometry allow the entire proteome complement of a cell or tissue type to be analyzed at once. This investigation employs such techniques in an effort to better understand the mechanisms of signal transduction for the contraction of smooth muscle tissue. The differential phosphorylation of proteins between resting and contracted tissue was targeted, specifically, because phosphorylation is the primary means of communication and activity modification of proteins. Much of what is known about the regulation of signal transduction in smooth muscle contraction is conducted through the activation of myosin light chain kinase (MLCK) and/or myosin light chain phosphatase (MLCP). Protocols of analysis using phosphoproteomic techniques and MALDI-TOF MS were developed for the purposes of this investigation. The localization of the more abundant proteins actin, myosin heavy chain (MHC), and tropomyosin was determined on a 2D gel. Tropomyosin was found to be phosphorylated in phorbol-contracted tissue, indicating that this protein may play a larger role in contractile regulation than originally thought. The function of such thin-filament associated proteins should be investigated more thoroughly. A thorough understanding of contraction in normal tissue will provide the base for which dysfunctions can be compared. Continued improvements in methodology will aid the advancement of this research