Discrete-time quantum walks on one-dimensional lattices

In this paper, we study discrete-time quantum walks on one-dimensional lattices. We find that the coherent dynamics depends on the initial states and coin parameters. For infinite size of lattice, we derive an explicit expression for the return probability, which shows scaling behavior $P(0,t)\sim t^{-1}$ and does not depends on the initial states of the walk. In the long-time limit, the probability distribution shows various patterns, depending on the initial states, coin parameters and the lattice size. The average mixing time $M_{\epsilon}$ closes to the limiting probability in linear $N$ (size of the lattice) for large values of thresholds $\epsilon$. Finally, we introduce another kind of quantum walk on infinite or even-numbered size of lattices, and show that the walk is equivalent to the traditional quantum walk with symmetrical initial state and coin parameter.Comment: 17 pages research not

Organisational determinants of Employer Image: A case of the Tourism Industry in Poland

Growing recognition of the importance of the customer-employee interaction in the tourism service delivery has led to the need to increase efforts to attract and retain qualified and committed personnel. The objective of the paper is to analyze the dimensions of the company employment image in the tourism industry and to identify organizational factors which influence the perception of the tourism organization attractiveness as a workplace by potential employees. The study was conducted on the group of 351 undergraduates and graduates enrolled in tourism and hospitality studies in Poznan. Research revealed that students do not believe that careers in tourism will offer them values they expect. It was also found that tourism company employment image is affected by company size, level of internationalization, chain affiliation, ownership type, and type of services offered

Prevalence and abundance of Cryptosporidium parvum and Giardia spp. in wild rural rodents from the Mazury Lake District region of Poland

Prevalence and abundance of Cryptosporodium parvum and Giardia spp. were studied in 3 species of rodents from forests and abandoned agricultural fields in N.E. Poland (Clethrionomys glareolus n=459; Microtus arvalis n=274; Apodemus flavicollis n=209). Overall prevalence was consistently higher in the voles compared with A. flavicollis (70±6, 73±0 and 27±8% respectively for C. parvum and 93±9, 96±3 and 48±3% respectively for Giardia spp.). Prevalence and abundance of infection also varied markedly across 3 years with 1998 being a year of higher prevalence and abundance with both species. Fewer older animals (especially C. glareolus and M. arvalis) carried infection with C. parvum and infections in these animals were relatively milder. Although seasonal differences were significant, no consistent pattern of changes was apparent. Host sex did not influence prevalence or abundance of infection with C. parvum, but made a small contribution to a 4-way interaction (in 5-way ANOVA) with other factors in the case of Giardia spp. The 2 species co-occurred significantly and in animals carrying both parasites there was a highly signficant positive correlation between abundance of infection with each, even with between-year, seasonal, host age, sex and species differences taken into account. Quantitative associations were confined to the 2 vole species in the study. These results are discussed in relation to the importance of wild rodents as reservoir hosts and sources of infection for local human communities

Controlling discrete quantum walks: coins and intitial states

In discrete time, coined quantum walks, the coin degrees of freedom offer the potential for a wider range of controls over the evolution of the walk than are available in the continuous time quantum walk. This paper explores some of the possibilities on regular graphs, and also reports periodic behaviour on small cyclic graphs.Comment: 10 (+epsilon) pages, 10 embedded eps figures, typos corrected, references added and updated, corresponds to published version (except figs 5-9 optimised for b&w printing here

Long-term spatiotemporal stability and dynamic changes in helminth infracommunities of bank voles (Myodes glareolus) in NE Poland

Parasites are considered to be an important selective force in host evolution but ecological studies of host-parasite systems are usually short-term providing only snap-shots of what may be dynamic systems. We have conducted four surveys of helminths of bank voles at three ecologically similar woodland sites in NE Poland, spaced over a period of 11 years, to assess the relative importance of temporal and spatial effects on helminth infracommunities. Some measures of infracom- munity structure maintained relative stability: the rank order of prevalence and abundance of Heligmosomum mixtum, Heligmosomoides glareoli and Mastophorus muris changed little between the four surveys. Other measures changed markedly: dynamic changes were evident in Syphacia petrusewiczi which declined to local extinction, while the capillariid Aonchotheca annulosa first appeared in 2002 and then increased in prevalence and abundance over the remaining three surveys. Some species are therefore dynamic and both introductions and extinctions can be expected in ecological time. At higher taxonomic levels and for derived measures, year and host-age effects and their interactions with site are import- ant. Our surveys emphasize that the site of capture is the major determinant of the species contributing to helminth community structure, providing some predictability in these systems

Отношение населения к экоотелям: пример Восточной Польши

Цель исследования - анализ отношения населения Восточной Польши (люблинское воеводство, Подкарпатское воеводство и Подляское воеводство) к отелям экологической направленности. Также в статье рассматривается, какие факторы влияют на платежеспособность респондентов при выборе места пребывания. Согласно выдвинутой гипотезе, на рынке услуг в Восточной Польше существуют группы туристов, которые при бронировании отеля обращают внимание на различные экологические аспекты, такие как наличие сертификата ISO 14001, экономное потребление энергии и использование безопасных способов утилизации отходов. Для достижения поставленной цели были проанализированы данные диагностического опроса с использованием оригинальной анкеты. Опрос проводился с мая по октябрь 2017 г. среди жителей Восточной Польши (0,02 % населения Люблинского воеводства, Подкарпатского воеводства и Подляского воеводства), пользующихся гостиничными услугами. Для статистических расчетов использовался анализ дискриминантных функций. Среди населения Восточной Польши в возрасте старше 60 лет был отмечен низкий интерес к выбору отелей, вовлеченных в экологическую деятельность. Кроме того, 25,89 % из них не имеют возможности платить более высокую цену за проживание в отеле, который инвестирует в охрану окружающей среды, в основном из-за низких доходов этой социальной группы. Что касается более молодых жителей Восточной Польши, чем они моложе, тем чаще головы доплачивать за проживание в отеле, заинтересованном в сохранении окружающей среды. Исследование показало, что восточные поляки в возрасте до 30 лет обладают высокой экологической сознательностью: 86,31 % из них готовы заплатить более высокую цену за проживание в подобных местах отдыха. В то же время эта часть населения формирует спрос на услуги экоотелей. Выявлены статистически значимые факторы, влияющие на выбор туристов из Восточной Польши: приготовление пищи из экологически чистых продуктов, экономное потребление энергии и наличие сертификата ISO 14001. Наиболее значимыми барьерами являются низкий доход жителей Восточной Польши, отсутствие знаний о проводимой в отеле экологической политике, недостаточное продвижение экоотелей, желание гостей забронировать самое дешевое жилье.The aim of the study is to analyse the attitudes of the society of Eastern Poland (Lublin voivodeship, Podkarpackie voivodeship and Podlaskie voivodeship) towards a range of hotels that declare the pro-ecological activities in their offer. Efforts have been made to identify barriers to higher prices for respondents from the surveyed regions as an increased cost of protecting the environment. The paper presents the hypothesis: on the market of accommodation services in Eastern Poland there are groups of tourists who, when booking an accommodation, pay attention to the environmental aspects of hotel operations, including the ISO 14001 certificate, an economical energy policy and a rational waste policy in the hotel. To achieve the intended purpose, the study used the method of a diagnostic survey with a research tool in the form of an original questionnaire that provided necessary data. The study was conducted from May to October 2017 among residents of Eastern Poland (0.02 % the population of residents in Lublin voivodeship, Podkarpackie voivodeship and Podlaskie voivodeship) using hotel accommodation services. The discriminant function analysis was used for statistical calculation. Among the population of Eastern Poland aged over 60, the interest in choosing a hotel that conducts pro-environmental activities is low. As many as 25.89 % of them are not able to pay a higher price for an accommodation in a hotel that conducts activities and investments in the field of environmental protection. This is mainly due to the low income of this social group. However, in groups of younger Poles from the Eastern Poland Region, the lower the age range, the fewer people would refuse to additionally pay for a service in a hotel that pursues pro-ecological policy. Eastern Poles up to 30 years old are more environmentally conscious. As many as 86.31 % of them are able to pay up higher price for a night in an eco-friendly hotel. At the same time, these people generate a greater demand for the services of ecological hotels. The significant statistical factors in choosing an eco-friendly hotel by guests from Eastern Poland were: the preparation of meals from organic products, running a cost-effective energy policy and having the ISO 14001 certificate. However, the statistically significant barriers were: low income related of consumers from Eastern Poland, lack of knowledge about environmental activities in hotels, no promotion of ecological hotels, to desire to purchase the cheapest accommodation by guests

A systematic review of the use of an expertise-based randomised controlled trial design

Acknowledgements JAC held a Medical Research Council UK methodology (G1002292) fellowship, which supported this research. The Health Services Research Unit, Institute of Applied Health Sciences (University of Aberdeen), is core-funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. Views express are those of the authors and do not necessarily reflect the views of the funders.Peer reviewedPublisher PD

Biodiversity surveys of grassland and coastal habitats in 2021 as a documentation of pre-war status in southern Ukraine

Background This paper presents two sampling-event datasets with occurrences of vascular plants, bryophytes and lichens collected in May-June 2021 in southern Ukraine. We aimed to collect high-quality biodiversity data in an understudied region and contribute it to international databases and networks. The study was carried out during the 15th Eurasian Dry Grassland Group (EDGG) Field Workshop in southern Ukraine and the Dark Diversity Network (DarkDivNet) sampling in the Kamianska Sich National Nature Park. By chance, these datasets were collected shortly before the major escalation of the Russian invasion in Ukraine. Surveyed areas in Kherson and Mykolaiv Regions, including established monitoring plots, were severely affected by military actions in 2022. Therefore, collected data are of significant value in the context of biodiversity documentation. The knowledge about the biodiversity of this area will help to assess the environmental impact of the war and plan restoration of the damaged or destroyed habitats. The first preliminary analysis of collected data demonstrates the biodiversity richness and conservation value of studied grassland habitats. New information We provide sampling-event datasets with 7467 occurrences, which represent 708 taxa (vascular plants, bryophytes and lichens) collected in 275 vegetation relevés. Amongst them, vascular plants are represented by 6665 occurrences (610 taxa), lichens - 420 (46) and bryophytes - 381 (51). Several new species were reported for the first time at the national or regional level. In particular, one vascular plant species (Torilis pseudonodosa) and two lichen species (Cladonia conista, Endocarpon loscosii) were new to Ukraine. One vascular plant (Stipa tirsa), two species of bryophytes (Rhynchostegium megapolitanum, Ptychostomum torquescens) and three species of lichens (Cladonia cervicornis, C. symphycarpa, Involucropyrenium breussi) were recorded for the first time for the Kherson Region. Additionally, these datasets contain occurrences of taxa with narrow distribution, specialists of rare habitat types and, therefore, represented by a low number of occurrences in relevant biodiversity databases and particularly in GBIF. This publication highlights the diversity of natural vegetation and its flora in southern Ukraine and raises conservation concerns