Exciton spectra in vertical stacks of triple and quadruple quantum dots in an electric field

We study an electron-hole pair in a stack of multiple quantum dots in the presence of an external electric field using the configuration interaction approach. We find that the bright energy levels can be grouped into families which are associated with the hole localized in a specific dot of the stack. The exciton energy levels undergo avoided crossings as function of the external electric field with different pattern for each family. We show that the variation of the depths of the dots along the stack can be deduced from the exciton spectrum. In the strong confinement limit the families are mixed by a weak electric field due to hole tunneling. This results in a characteristic multiple avoided crossing of energy levels belonging to different families with an accompanying modulation of the recombination probabilities and an appearance of a single particularly bright state. We discuss the modification of the spectrum when dots are added to the stack.Comment: submitted to PR

End‑of‑life care for patients with advanced lung cancer and chronic obstructive pulmonary disease: Survey among Polish pulmonologists

Copyright by Medycyna Praktyczna, Kraków 2019 INTRODUCTION There is evidence that people with nonmalignant disease receive poorer end‑of‑life (EOL) care compared with people with cancer. OBJECTIVES The aim of the study was to assess the selected aspects of symptomatic treatment and communication between physicians and patients diagnosed with either advanced chronic obstructive pulmonary disease (COPD) or lung cancer. METHODS A questionnaire survey was conducted online among members of the Polish Respiratory Society. RESULTS Properly completed questionnaires were returned by 174 respondents (27.2% of those proved to be contacted by email). In COPD, 32% of respondents always or often used opioids in chronic breathlessness and 18.3% always or often referred patients to a palliative care (PC) specialist. Nearly 80% of the respondents claimed that bedside discussions on EOL issues with people with COPD are essential, although only 20% would always or often initiate them. In people with lung cancer, opioids were routinely used for relief of chronic breathlessness by 80% of physicians; 81.7% referred patients to a PC specialist. More than half of the respondents always or often discussed EOL issues only with the patient’s caregivers or relatives. Younger physicians, those at an earlier stage of their career, those caring for higher numbers of patients with lung cancer, and those who were better acquainted with Polish Respiratory Society recommendations for PC in chronic lung diseases seemed to provide better EOL care for COPD patients. CONCLUSIONS Patients with COPD, as compared with patients with lung cancer, were less frequently treated with opioids to relieve chronic breathlessness or referred for a PC consultation. Discussing the EOL issues with a patient was generally found challenging by physicians, and most often pursued with caregivers instead. The COPD recommendations on PC may prove helpful in providing better EOL care by pulmonologists

Measurement of the Fermi Constant by FAST

An initial measurement of the lifetime of the positive muon to a precision of 16 parts per million (ppm) has been performed with the FAST detector at the Paul Scherrer Institute. The result is tau_mu = 2.197083 (32) (15) microsec, where the first error is statistical and the second is systematic. The muon lifetime determines the Fermi constant, G_F = 1.166353 (9) x 10^-5 GeV^-2 (8 ppm).Comment: 15 pages, 6 figure

A mobile data acquisition system

A mobile data aquisition (MobiDAQ) was developed for the ATLAS central hadronic calorimeter (TileCal). MobiDAQ has been designed in order to test the functionalities of the TileCal front-end electronics and to acquire calibration data before the final back-end electronics were built and tested. MobiDAQ was also used to record the first cosmic ray events acquired by an ATLAS subdetector in the underground experimental area

Electroweak Physics, Experimental Aspects

Collider measurements on electroweak physics are summarised. Although the precision on some observables is very high, no deviation from the Standard Model of electroweak interactions is observed. The data allow to set stringent limits on some models for new physics.Comment: Plenary Talk at the UK Phenomenology Workshop on Collider Physics, Durham, 199

Improving Prediction of Real-Time Loneliness and Companionship Type Using Geosocial Features of Personal Smartphone Data

Loneliness is a widely affecting mental health symptom and can be mediated by and co-vary with patterns of social exposure. Using momentary survey and smartphone sensing data collected from 129 Android-using college student participants over three weeks, we (1) investigate and uncover the relations between momentary loneliness experience and companionship type and (2) propose and validate novel geosocial features of smartphone-based Bluetooth and GPS data for predicting loneliness and companionship type in real time. We base our features on intuitions characterizing the quantity and spatiotemporal predictability of an individual's Bluetooth encounters and GPS location clusters to capture personal significance of social exposure scenarios conditional on their temporal distribution and geographic patterns. We examine our features' statistical correlation with momentary loneliness through regression analyses and evaluate their predictive power using a sliding window prediction procedure. Our features achieved significant performance improvement compared to baseline for predicting both momentary loneliness and companionship type, with the effect stronger for the loneliness prediction task. As such we recommend incorporation and further evaluation of our geosocial features proposed in this study in future mental health sensing and context-aware computing applications.This work was supported by Whole Communities—Whole Health, a research grand challenge at the University of Texas at AustinOffice of the VP for Researc

Neutron recognition in the LAND detector for large neutron multiplicity

The performance of the LAND neutron detector is studied. Using an event-mixing technique based on one-neutron data obtained in the S107 experiment at the GSI laboratory, we test the efficiency of various analytic tools used to determine the multiplicity and kinematic properties of detected neutrons. A new algorithm developed recently for recognizing neutron showers from spectator decays in the ALADIN experiment S254 is described in detail. Its performance is assessed in comparison with other methods. The properties of the observed neutron events are used to estimate the detection efficiency of LAND in this experiment.Comment: 16 pages, 8 figure