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1.
Phys Rev Lett ; 121(4): 043401, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30095960

RESUMO

We establish a conceptual framework for the identification and the characterization of induced interactions in binary mixtures and reveal their intricate relation to entanglement between the components or species of the mixture. Exploiting an expansion in terms of the strength of the entanglement among the two species enables us to deduce an effective single-species description. In this way, we naturally incorporate the mutual feedback of the species and obtain induced interactions for both species which are effectively present among the particles of same type. Importantly, our approach incorporates few-body and inhomogeneous systems extending the scope of induced interactions where two particles interact via a bosonic bath-type environment. Employing the example of a one-dimensional ultracold Bose-Fermi mixture, we obtain induced Bose-Bose and Fermi-Fermi interactions with short-range attraction and long-range repulsion. With this, we show how beyond species mean-field physics visible in the two-body correlation functions can be understood via the induced interactions.

2.
Phys Rev Lett ; 119(6): 063001, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28949595

RESUMO

We present an in-depth many-body investigation of the so-called mesoscopic molecular ions that can buildup when an ion is immersed into an atomic Bose-Einstein condensate in one dimension. To this end, we employ the multilayer multiconfiguration time-dependent Hartree method for mixtures of ultracold bosonic species for solving the underlying many-body Schrödinger equation. This enables us to unravel the actual structure of such massive charged molecules from a microscopic perspective. Laying out their phase diagram with respect to atom number and interatomic interaction strength, we determine the maximal number of atoms bound to the ion and reveal spatial densities and molecular properties. Interestingly, we observe a strong interaction-induced localization, especially for the ion, that we explain by the generation of a large effective mass, similarly to ions in liquid Helium. Finally, we predict the dynamical response of the ion to small perturbations. Our results provide clear evidence for the importance of quantum correlations, as we demonstrate by benchmarking them with wave function ansatz classes employed in the literature.

3.
J Chem Phys ; 147(4): 044106, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28764383

RESUMO

We extent the recently developed Multi-Layer Multi-Configuration Time-Dependent Hartree method for Bosons for simulating the correlated quantum dynamics of bosonic mixtures to the fermionic sector and establish a unifying approach for the investigation of the correlated quantum dynamics of a mixture of indistinguishable particles, be it fermions or bosons. Relying on a multi-layer wave-function expansion, the resulting Multi-Layer Multi-Configuration Time-Dependent Hartree method for Mixtures (ML-MCTDHX) can be adapted to efficiently resolve system-specific intra- and inter-species correlations. The versatility and efficiency of ML-MCTDHX are demonstrated by applying it to the problem of colliding few-atom mixtures of both Bose-Fermi and Fermi-Fermi types. Thereby, we elucidate the role of correlations in the transmission and reflection properties of the collisional events. In particular, we present examples where the reflection (transmission) at the other atomic species is a correlation-dominated effect, i.e., it is suppressed in the mean-field approximation.

4.
Adv Parasitol ; 95: 315-493, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28131365

RESUMO

Alveolar echinococcosis (AE) and cystic echinococcosis (CE) are severe helminthic zoonoses. Echinococcus multilocularis (causative agent of AE) is widely distributed in the northern hemisphere where it is typically maintained in a wild animal cycle including canids as definitive hosts and rodents as intermediate hosts. The species Echinococcus granulosus, Echinococcus ortleppi, Echinococcus canadensis and Echinococcus intermedius are the causative agents of CE with a worldwide distribution and a highly variable human disease burden in the different endemic areas depending upon human behavioural risk factors, the diversity and ecology of animal host assemblages and the genetic diversity within Echinococcus species which differ in their zoonotic potential and pathogenicity. Both AE and CE are regarded as neglected zoonoses, with a higher overall burden of disease for CE due to its global distribution and high regional prevalence, but a higher pathogenicity and case fatality rate for AE, especially in Asia. Over the past two decades, numerous studies have addressed the epidemiology and distribution of these Echinococcus species worldwide, resulting in better-defined boundaries of the endemic areas. This chapter presents the global distribution of Echinococcus species and human AE and CE in maps and summarizes the global data on host assemblages, transmission, prevalence in animal definitive hosts, incidence in people and molecular epidemiology.


Assuntos
Equinococose/epidemiologia , Echinococcus/fisiologia , Saúde Global , Animais , Equinococose/parasitologia , Equinococose/transmissão , Equinococose Hepática/epidemiologia , Equinococose Hepática/parasitologia , Equinococose Hepática/transmissão , Humanos , Incidência , Epidemiologia Molecular , Prevalência , Zoonoses
5.
One Health ; 2: 166-174, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28616494

RESUMO

The One Health (OH) concept provides an integrated framework for observing and improving health issues involving human, animal, and environmental factors, and has been applied in particular to zoonotic disease problems. We conducted a systematic review of English and Chinese language peer-reviewed and grey literature databases to identify zoonotic endoparasite research utilizing an OH approach in community-based settings. Our review identified 32 articles where specimens collected simultaneously from all three OH domains (people, animals, and the environment) were assessed for endoparasite infection or exposure. Study sites spanned 23 countries, and research teams brought together an average of seven authors from two countries. Surveillance of blood-borne and gastrointestinal protozoa were most frequently reported (19 of 32; 59%), followed by trematodes, nematodes, and cestodes. Laboratory techniques varied greatly between studies, and only 16 identified parasites using Polymerase Chain Reaction (PCR) in all three OH domains. Our review identified important gaps in parasitology research operating under an OH framework. We recommend that investigators working in the realm of zoonotic disease strive to evaluate all three OH domains by integrating modern molecular tools as well as techniques provided by economists and social scientists.

6.
Zoonoses Public Health ; 62(6): 445-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25439233

RESUMO

Free-roaming dog populations are a global concern for animal and human health including transmission of infectious disease (e.g. rabies, distemper and parasites), dog bite injuries/mortalities, animal welfare and adverse effects on wildlife. In Saskatchewan (SK), Canada, veterinary care is difficult to access in the remote and sparsely inhabited northern half of the province, where the population is predominately Indigenous. Even where veterinary clinics are readily available, there are important barriers such as cost, lack of transportation, unique cultural perspectives on dog husbandry and perceived need for veterinary care. We report the effects of introducing a community action plan designed to improve animal and human health, increase animal health literacy and benefit community well-being in two Indigenous communities where a dog-related child fatality recently occurred. Initial door-to-door dog demographic surveys indicated that most dogs were sexually intact (92% of 382 dogs), and few had ever been vaccinated (6%) or dewormed (6%). Approximately three animal-related injuries requiring medical care were reported in the communities per 1000 persons per year (95% CL: 1.6-6.6), and approximately 86% of 145 environmentally collected dog faecal samples contained parasites, far above levels reported in other urban or rural settings in SK. Following two subsidized spay/neuter clinics and active rehoming of dogs, parasite levels in dog faeces decreased significantly (P < 0.001), and important changes were observed in the dog demographic profile. This project demonstrates the importance of engaging people using familiar, local resources and taking a community specific approach. As well, it highlights the value of integrated, cross-jurisdictional cooperation, utilizing the resources of university researchers, veterinary personnel, public health, environmental health and community-based advocates to work together to solve complex issues in One Health. On-going surveillance on dog bites, parasite levels and dog demographics are needed to measure the long-term sustainability of benefits to dog, human and wildlife health.


Assuntos
Bem-Estar do Animal , Controle de Doenças Transmissíveis/métodos , Doenças do Cão/prevenção & controle , Prática de Saúde Pública , Adolescente , Adulto , Animais , Comportamento Animal , Mordeduras e Picadas/epidemiologia , Castração/veterinária , Criança , Pesquisa Participativa Baseada na Comunidade , Demografia/estatística & dados numéricos , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Fezes/parasitologia , Feminino , Inquéritos Epidemiológicos , Humanos , Indígenas Norte-Americanos , Masculino , Reação em Cadeia da Polimerase , Saúde da População Rural , População Rural , Saskatchewan , Vacinação/estatística & dados numéricos , Vacinação/veterinária , Adulto Jovem
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