Local in time master equations with memory effects: Applicability and interpretation

Non-Markovian local in time master equations give a relatively simple way to describe the dynamics of open quantum systems with memory effects. Despite their simple form, there are still many misunderstandings related to the physical applicability and interpretation of these equations. Here we clarify these issues both in the case of quantum and classical master equations. We further introduce the concept of a classical non-Markov chain signified through negative jump rates in the chain configuration.Comment: Special issue on loss of coherence and memory effects in quantum dynamics, J. Phys. B., to appea

Confronting the vicinity of the surface water and sea shore in a shallow glaciogenic aquifer in southern Finland

The groundwater in a shallow, unconfined, low-lying coastal aquifer in Santala, southern Finland, was chemically characterised by integrating multivariate statistical approaches, principal component analysis (PCA) and hierarchical cluster analysis (HCA), based on the stable isotopes delta H-2 and delta O-18, hydrogeochemistry and field monitoring data. PCA and HCA yielded similar results and classified groundwater samples into six distinct groups that revealed the factors controlling temporal and spatial variations in the groundwater geochemistry, such as the geology, anthropogenic sources from human activities, climate and surface water. High temporal variation in groundwater chemistry directly corresponded to precipitation. With an increase in precipitation, KMnO4 consumption, EC, alkalinity and Ca concentrations also increased in most wells, while Fe, Al, Mn and SO4 were occasionally increased during spring after the snowmelt under specific geological conditions. The continued increase in NO3 and metal concentrations in groundwater indicates the potential contamination risk to the aquifer. Stable isotopes of delta O-18 and delta H-2 indicate groundwater recharge directly from meteoric water, with an insignificant contribution from lake water, and no seawater intrusion into the aquifer. Groundwater geochemistry suggests that local seawater intrusion is temporarily able to take place in the sulfate reduction zone along the freshwater and seawater mixed zone in the low-lying coastal area, but the contribution of seawater was found to be very low. The influence of lake water could be observed from higher levels of KMnO4 consumption in wells near the lake. The integration of PCA and HCA with conventional classification of groundwater types, as well as with the hydrogeochemical data, provided useful tools to identify the vulnerable groundwater areas representing the impacts of both natural and human activities on water quality and the understanding of complex groundwater flow system for the aquifer vulnerability assessment and groundwater management in the future.Peer reviewe

Evaluating the effects of bilingual traffic signs on driver performance and safety

Variable Message Signs (VMS) can provide immediate and relevant information to road users and bilingual VMS can provide great flexibility in countries where a significant proportion of the population speak an alternative language to the majority. The study reported here evaluates the effect of various bilingual VMS configurations on driver behaviour and safety. The aim of the study was to determine whether or not the visual distraction associated with bilingual VMS signs of different configurations (length, complexity) impacted on driving performance. A driving simulator was used to allow full control over the scenarios, road environment and sign configuration and both longitudinal and lateral driver performance was assessed. Drivers were able to read one and two-line monolingual signs and two-line bilingual signs without disruption to their driving behaviour. However, drivers significantly reduced their speed in order to read four-line monolingual and four-line bilingual signs, accompanied by an increase in headway to the vehicle in front. This implies that drivers are possibly reading the irrelevant text on the bilingual sign and various methods for reducing this effect are discussed

Nuorten avomuotoinen OPI-mielenterveyskuntoutus : Koettu hyöty ja vaikuttavuus sekä kuntoutusmallin soveltuvuus

OPI-hankkeen tarkoituksena oli kehittää avomuotoista kuntoutusmallia ammatillisessa koulutuksessa oleville 16–25-vuotiaille opiskelijoille, joilla oli diagnosoitu masennus- ja/tai ahdistuneisuushäiriö. Kuntoutusmallilla pyrittiin tukemaan nuoria elämänhallinnassa ja opiskelussa, vahvistamaan nuoren toimintakykyä ja hyvinvointia sekä vähentämään mielenterveysongelmiin liittyviä haittoja. Vuosina 2011–2013 toteutettiin yhteensä kahdeksan avomuotoista ryhmäkuntoutuskurssia, joihin kuului myös yksilökäyntejä sekä verkostotapaamisia. Kurssit kestivät seurantoineen noin 1,5 vuotta ja ne toteutettiin lukukausien aikana. OPI-hankkeen yhteydessä toteutettiin arviointitutkimus, jonka tavoite oli selvittää kuntoutusmallin koettua hyötyä ja vaikuttavuutta, sidosryhmäyhteistyötä sekä kuntoutusmallin soveltuvuutta vakiintuneeksi toiminnaksi. Tutkimukseen osallistui 70 kuntoutujaa. Aineistoa kerättiin kyselylomakkeilla sekä eri tahojen haastatteluilla (kuntoutujat, projektiryhmät). Kuntoutuksen ja opiskelujen yhteen nivominen onnistui enimmäkseen hyvin. Ryhmässä saatu vertaistuki koettiin kuntoutuksen suurimmaksi anniksi. Seuranta-aikana nuorten masennusoireet vähenivät, elämänlaatu, itse arvioitu terveydentila sekä opiskelukyky ja kognitiivinen toimintakyky kohentuivat. Nuoret olisivat kuitenkin tarvinneet kuntoutusta jo varhaisemmassa vaiheessa. Noin kolme nuorta neljästä arvioi, että oli saavuttanut kuntoutukselle asettamansa tavoitteet vähintään melko hyvin. Tavoitteiden saavuttaminen ja kuntoutuksen koettu vaikuttavuus olivat yhteydessä kuntoutuksen oikea-aikaisuuteen, yhteistyöhön hoitavan tahon sekä opiskeluterveydenhuollon kanssa sekä vuorovaikutuksen onnistumiseen ohjaajan ja nuoren välillä. Tutkimuksen tulokset antavat varsin rohkaisevan kuvan oppilaitoksen kanssa yhteistyössä toimivan ja opintojen kanssa yhteen sovitetun kuntoutuksen mahdollisuuksista nuorten syrjäytymisen ehkäisemisessä

Measurement of the Total Active 8B Solar Neutrino Flux at the Sudbury Neutrino Observatory with Enhanced Neutral Current Sensitivity

The Sudbury Neutrino Observatory (SNO) has precisely determined the total active (nu_x) 8B solar neutrino flux without assumptions about the energy dependence of the nu_e survival probability. The measurements were made with dissolved NaCl in the heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27 (stat) +/- 0.38 (syst) x10^6 cm^{-2}s^{-1}, in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Delta m^{2} = 7.1^{+1.2}_{-0.6}x10^{-5} ev^2 and theta = 32.5^{+2.4}_{-2.3} degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.Comment: Submitted to Phys. Rev. Let

Development of a New Clusterization Method for the GEM-TPC Detector

The Facility for Antiproton and Ion Research FAIR, in Darmstadt Germany, will be one of the largest accelerator laboratories worldwide. The Superconducting FRagment Separator (Super-FRS)* is one of its main components. The Super-FRS can produce, separate and deliver high-energy radioactive beams with intensities up to 1e11 ions/s, covering projectiles from protons up to uranium and it can be used as an independent experimental device. The Gas Electron Multiplier-based Time Projection Chambers (GEM-TPC) in twin configuration is a newly developed beam tracking detector capable of providing spatial resolution of less than 1 mm with a tracking efficiency close to 100% at 1 MHz counting rate. The GEM-TPC (HGB4) was tested at the FRagment Separator (FRS), with 238U beam at 850 MeV/u. A new clusterization method was developed, for the first time and used for an analysis. This method allowed to access to waveforms of each strip signal within a single trigger in an event-by-event basis. The procedures involved in this method will be shown in details.Peer reviewe

Electron Antineutrino Search at the Sudbury Neutrino Observatory

Upper limits on the \nuebar flux at the Sudbury Neutrino Observatory have been set based on the \nuebar charged-current reaction on deuterium. The reaction produces a positron and two neutrons in coincidence. This distinctive signature allows a search with very low background for \nuebar's from the Sun and other potential sources. Both differential and integral limits on the \nuebar flux have been placed in the energy range from 4 -- 14.8 MeV. For an energy-independent \nu_e --> \nuebar conversion mechanism, the integral limit on the flux of solar \nuebar's in the energy range from 4 -- 14.8 MeV is found to be \Phi_\nuebar <= 3.4 x 10^4 cm^{-2} s^{-1} (90% C.L.), which corresponds to 0.81% of the standard solar model 8B \nu_e flux of 5.05 x 10^6 cm^{-2} s^{-1}, and is consistent with the more sensitive limit from KamLAND in the 8.3 -- 14.8 MeV range of 3.7 x 10^2 cm^{-2} s^{-1} (90% C.L.). In the energy range from 4 -- 8 MeV, a search for \nuebar's is conducted using coincidences in which only the two neutrons are detected. Assuming a \nuebar spectrum for the neutron induced fission of naturally occurring elements, a flux limit of Phi_\nuebar <= 2.0 x 10^6 cm^{-2} s^{-1}(90% C.L.) is obtained.Comment: submitted to Phys. Rev.

Women on boards and firm performance

This study investigates the financial performance of Dutch companies both with and without women on their boards. The analysis extends earlier methods used in research by Catalyst (The bottom line: corporate performance and women's representation on boards, 2007) and McKinsey (Women matter. Gender diversity, a corporate performance driver. McKinsey & Company, USA, 2007), two studies that are often cited in the literature, although, each has a number of methodological shortcomings. This article adds to the international debate, which is often normative, through examining 99 listed companies in the Dutch Female Board Index. Our results show that firms with women directors perform better than those without women on their boards

A Search for Neutrinos from the Solar hep Reaction and the Diffuse Supernova Neutrino Background with the Sudbury Neutrino Observatory

A search has been made for neutrinos from the hep reaction in the Sun and from the diffus