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The design of quantum hardware that reduces and mitigates errors is essential for practical quantum error correction (QEC) and useful quantum computation. To this end, we introduce the circuit-Quantum Electrodynamics (QED) dual-rail qubit in which our physical qubit is encoded in the single-photon subspace, [Formula: see text], of two superconducting microwave cavities. The dominant photon loss errors can be detected and converted into erasure errors, which are in general much easier to correct. In contrast to linear optics, a circuit-QED implementation of the dual-rail code offers unique capabilities. Using just one additional transmon ancilla per dual-rail qubit, we describe how to perform a gate-based set of universal operations that includes state preparation, logical readout, and parametrizable single and two-qubit gates. Moreover, first-order hardware errors in the cavities and the transmon can be detected and converted to erasure errors in all operations, leaving background Pauli errors that are orders of magnitude smaller. Hence, the dual-rail cavity qubit exhibits a favorable hierarchy of error rates and is expected to perform well below the relevant QEC thresholds with today's coherence times.
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Listeria species prevalence has been investigated at nearly all stages of the fresh produce supply chain; however, it has not been examined in transportation and distribution center (DC) related environments. Between December 2019 and March 2021, 18 DCs handling fresh produce were environmentally sampled for Listeria. Swab samples were collected from a variety of surfaces (e.g., floors, pallets, forklifts) in several areas of each DC (e.g., cold storage, shipping and receiving docks). Impaction air samples, relative humidity, and temperature data were also collected. While no Listeria spp. were isolated from air samples (n = 170), they were isolated from 49 of 982 (ca. 5%) environmental samples. The proportion of Listeria spp. positive samples varied significantly across individual DCs (P < 0.01). Several facility characteristics were significantly associated with a Listeria spp. positive sample, such as zone, sampling site dryness, and cleaning regimen. A random forest model (sensitivity: 0.786, specificity: 0.874) identified geographical location and general sampling location (e.g., cold storage rooms, shipping docks) as the two most important variables associated with Listeria spp. detection. This study identified likely harborage sites (e.g., floors, cleaning equipment) of Listeria spp. in DCs across the US and emphasized the importance of sanitation operations in Listeria-prone areas.
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Listeria monocytogenes , Listeria , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Listeria/genética , PrevalênciaRESUMO
Superconducting qubits are a leading platform for scalable quantum computing and quantum error correction. One feature of this platform is the ability to perform projective measurements orders of magnitude more quickly than qubit decoherence times. Such measurements are enabled by the use of quantum-limited parametric amplifiers in conjunction with ferrite circulators-magnetic devices which provide isolation from noise and decoherence due to amplifier backaction. Because these nonreciprocal elements have limited performance and are not easily integrated on chip, it has been a long-standing goal to replace them with a scalable alternative. Here, we demonstrate a solution to this problem by using a superconducting switch to control the coupling between a qubit and amplifier. Doing so, we measure a transmon qubit using a single, chip-scale device to provide both parametric amplification and isolation from the bulk of amplifier backaction. This measurement is also fast, high fidelity, and has 70% efficiency, comparable to the best that has been reported in any superconducting qubit measurement. As such, this work constitutes a high-quality platform for the scalable measurement of superconducting qubits.
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We introduce a method for breaking Lorentz reciprocity based upon the noncommutation of frequency conversion and delay. The method requires no magnetic materials or resonant physics, allowing for the design of scalable and broadband nonreciprocal circuits. With this approach, two types of gyrators-universal building blocks for linear, nonreciprocal circuits-are constructed. Using one of these gyrators, we create a circulator with >15 dB of isolation across the 5-9 GHz band. Our designs may be readily extended to any platform with suitable frequency conversion elements, including semiconducting devices for telecommunication or an on-chip superconducting implementation for quantum information processing.
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Listeria monocytogenes is an increasing food safety concern throughout the produce supply chain as it has been linked to produce associated outbreaks and recalls. To our knowledge, this is the first systematic literature review to investigate Listeria species and L. monocytogenes prevalence, persistence, and diversity at each stage along the supply chain. This review identified 64 articles of 4863 candidate articles obtained from four Boolean search queries in six databases. Included studies examined naturally detected/isolated Listeria species and L. monocytogenes in fresh produce-related environments, and/or from past fresh produce associated outbreaks or from produce directly. Listeria species and L. monocytogenes were detected in each stage of the fresh produce supply chain. The greatest prevalence of Listeria species was observed in natural environments and outdoor production, with prevalence generally decreasing with each progression of the supply chain (e.g., packinghouse to distribution to retail). L. monocytogenes prevalence ranged from 61.1% to not detected (0.00%) across the entire supply chain for included studies. Listeria persistence and diversity were also investigated more in natural, production, and processing environments, compared to other supply chain environments (e.g., retail). Data gaps were identified for future produce safety research, for example, in the transportation and distribution center environment.
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ABSTRACT: Cross-contamination of raw food to other surfaces, hands, and foods is a serious issue in food service. With individuals eating more meals away from home, contracting a foodborne illness from a food service establishment is an increasing concern. However, most studies have concentrated on hands or food contact surfaces and neglected atypical and unusual surfaces (surfaces that are not typically identified as a source of cross-contamination) and venues. This review was conducted to identify atypically cross-contaminated surfaces and atypical venues where cross-contamination could occur that have not been examined thoroughly in the literature. Most surfaces that could be at risk for cross-contamination are frequently touched, are rarely cleaned and sanitized, and can support the persistence and/or growth of foodborne pathogens. These surfaces include menus, spice and condiment containers, aprons and coveralls, mobile devices and tablets, and money. Venues that are explored, such as temporary events, mobile vendors, and markets, are usually limited in space or infrastructure, have low compliance with proper hand washing, and provide the opportunity for raw and ready-to-eat foods to come into contact with one another. These factors create an environment in which cross-contamination can occur and potentially impact food safety. A more comprehensive cleaning and sanitizing regime encompassing these surfaces and venues could help mitigate cross-contamination. This review highlights key surfaces and venues that have the potential to be cross-contaminated and have been underestimated or not fully investigated. These knowledge gaps indicate where further work is needed to fully understand the role of these surfaces and venues in cross-contamination and how it can be prevented.
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Serviços de Alimentação , Doenças Transmitidas por Alimentos , Contaminação de Alimentos/análise , Manipulação de Alimentos , Microbiologia de Alimentos , Inocuidade dos Alimentos , Mãos , Desinfecção das Mãos , HumanosRESUMO
Published research on outbreaks of gastrointestinal illness has focused primarily on the results of epidemiological and clinical data collected postoutbreak; little research has been done on actual preventative practices during an outbreak. In this study, the authors observed student compliance with hand hygiene recommendations at the height of a suspected norovirus outbreak in a university residence in Ontario, Canada. Data on observed practices was compared to postoutbreak self-report surveys administered to students to examine their beliefs and perceptions about hand hygiene. Observed compliance with prescribed hand hygiene recommendations occurred 17.4% of the time. Despite knowledge of hand hygiene protocols and low compliance, 83.0% of students indicated that they practiced correct hand hygiene during the outbreak. To proactively prepare for future outbreaks, a current and thorough crisis communications and management strategy, targeted at a university student audience and supplemented with proper hand washing tools, should be enacted by residence administration.
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Controle de Doenças Transmissíveis/métodos , Transmissão de Doença Infecciosa/prevenção & controle , Gastroenterite/prevenção & controle , Desinfecção das Mãos , Higiene , Estudantes/psicologia , Adolescente , Adulto , Surtos de Doenças , Feminino , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos Epidemiológicos , Humanos , Masculino , Ontário , Características de Residência , Percepção Social , Estudantes/estatística & dados numéricos , Universidades , Adulto JovemRESUMO
In May 2016, labeling of certain nonintact mechanically tenderized beef (MTB) products was mandated in the United States. MTB products should be handled differently by the consumer because pathogens can be transferred from the exterior to the interior of the meat during the tenderization process. Without labeling, it is difficult to visually distinguish between some intact beef and MTB products, which is a concern because MTB products require higher internal cooking temperatures for safety. An exploratory study was conducted to understand consumer understanding of MTB products and consumer responses to the new label. Thirteen focus groups were convened in rural and urban settings across Virginia and North Carolina between December 2015 and May 2016. Sessions were audiorecorded, transcribed verbatim, and analyzed through constant-comparison thematic analysis. Although MTB products were commonly bought, prepared, and consumed, consumer awareness of MTB products and the MTB process was limited. Generally, the label confused participants, and they did not understand the message. Specifically, terminology such as "blade tenderized" and "mechanically tenderized" were preferred over the term "needle tenderized" on labels. Once explained, many individuals wanted more information and better messaging. Through a multiprong approach, other messaging methods (e.g., in stores, through technology, and with certifications) were highly valued by consumers and may result in increased message clarity. Ultimately, the intrinsic and extrinsic properties of the beef rather than the MTB product continued to be the primary guide for purchasing and preparation. This study is the first to be conducted regarding American perceptions of MTB products. An understanding of consumer awareness of MTB products and labels is needed to develop targeted risk messaging communication tools.
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Comportamento do Consumidor , Grupos Focais , Manipulação de Alimentos , Rotulagem de Alimentos , Microbiologia de Alimentos , Carne Vermelha , Animais , Bovinos , Contagem de Colônia Microbiana , Comportamento do Consumidor/estatística & dados numéricos , Grupos Focais/estatística & dados numéricos , Manipulação de Alimentos/métodos , Rotulagem de Alimentos/estatística & dados numéricos , Humanos , North Carolina , Carne Vermelha/microbiologia , Estados Unidos , VirginiaRESUMO
Consumers are increasingly interested in the attributes of the food they consume. This includes what is in the food and how it was raised; and at least some consumers are willing to pay a premium for products with specific attributes. However, the current plethora of labels on the market does not adequately address this issue; rather than providing actionable information, most labels add to the consumer confusion. In addition, there is a tendency toward "absence labels" that can contribute to a negative consumer perception of conventional products that may or may not include the attribute in question. Communication with consumers about the complex and highly technical issue of antimicrobial resistance (AMR) is challenging, and experiences from communication efforts about food safety-related issues demonstrate exactly how challenging this is to communicate clearly. General lessons learned from the science of risk communication can help guide efforts to communicate about the challenging issue of AMR. There are efforts underway to chart out a new approach. A new labeled animal production certification program is under development to provide choice for consumers, while reducing consumer confusion, which mandates antibiotic stewardship practices.
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Infecções Bacterianas/transmissão , Comportamento do Consumidor , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Inocuidade dos Alimentos , Animais , Antibacterianos/administração & dosagem , Infecções Bacterianas/microbiologia , Rotulagem de Alimentos , Fatores de RiscoRESUMO
This article covers the current published literature related to the use of social media in food safety and infectious disease communication. The aim was to analyze literature recommendations and draw conclusions about how best to utilize social media for food safety risk communication going forward. A systematic literature review was conducted, and 24 articles were included for analysis. The inclusion criteria were (i) original peer-reviewed articles and (ii) primary focus on communication through social media about food safety and/or infectious diseases. Studies were coded for themes about social media applications, benefits, limitations, and best practices. Trust and personal beliefs were important drivers of social media use. The wide reach, immediacy, and information gathering capacities of social media were frequently cited benefits. Suggestions for social media best practices were inconsistent among studies, and study designs were highly variable. More evidence-based suggestions are needed to better establish guidelines for social media use in food safety and infectious disease risk communication. The information gleaned from this review can be used to create effective messages for shaping food safety behaviors.
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Qualidade de Produtos para o Consumidor , Comunicação em Saúde , Mídias Sociais , Inocuidade dos Alimentos , Humanos , RiscoRESUMO
Folklorama in Winnipeg, Manitoba, Canada, is a 14-day temporary food service event that explores the many different cultural realms of food, food preparation, and entertainment. In 2010, the Russian pavilion at Folklorama was implicated in a foodborne outbreak of Escherichia coli O157 that caused 37 illnesses and 18 hospitalizations. The ethnic nature and diversity of foods prepared within each pavilion presents a unique problem for food inspectors, as each culture prepares food in their own very unique way. The Manitoba Department of Health and Folklorama Board of Directors realized a need to implement a food safety information delivery program that would be more effective than a 2-h food safety course delivered via PowerPoint slides. The food operators and event coordinators of five randomly chosen pavilions selling potentially hazardous food were trained on-site, in their work environment, focusing on critical control points specific to their menu. A control group (five pavilions) did not receive on-site food safety training and were assessed concurrently. Public health inspections for all 10 pavilions were performed by Certified Public Health Inspectors employed with Manitoba Health. Critical infractions were assessed by means of standardized food protection inspection reports. The results suggest no statistically significant difference in food inspection scores between the trained and control groups. However, it was found that inspection report results increased for both the control and trained groups from the first inspection to the second, implying that public health inspections are necessary in correcting unsafe food safety practices. The results further show that in this case, the 2-h food safety course delivered via slides was sufficient to pass public health inspections. Further evaluations of alternative food safety training approaches are warranted.