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In this paper, we investigate a scenario in which protected and unprotected services coexist in an elastic optical network under dynamic traffic. In the investigated scenario, unprotected services can reuse the reserved idle bandwidth to provide protection to the protected services. Under this scenario, we propose a new heuristic algorithm that enables such reuse as well as define and introduce a new assignment problem in elastic optical networks, named a Transmission Spectrum Assignment (T-SA) problem. In this paper, we consider a scenario in which services may be routed using the multipath routing approach. Additionally, protection using bandwidth squeezing is also considered. We assess our proposal through simulations on three different network topologies and compare our proposal against the classical protection approach, in which bandwidth reuse is not allowed. For the simulated range of network loads, the maximum (minimum) blocking probability reduction obtained by our proposal is approximately 48% (10%) in the European topology, 46% (7%) in the NSFNET topology, and 32% (6%) in the German topology.

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The illicit exploitation of Brazilwood (Paubrasilia echinata) presents a significant challenge in Brazil, given its substantial value in the global production of bows for musical instruments. To address timber provenance, the use of strontium (Sr) isotope ratios as indicators of bedrock signatures has emerged as a robust tool in forensic investigations. In this study, we critically evaluate the efficacy of this approach using Sr isotope data derived from bulk soils and trees collected at two distinct sites in Brazil. Despite the statistically indistinguishable 87Sr/86Sr ratios observed in the investigated tree species, the compiled 87Sr/86Sr isotope ratios of Brazilwood from Brazilwood National Park (PNPB) and the ES Group provide valuable insights into the potential application of this method for tracing forensic timber seizures. This pilot study also addresses crucial sampling considerations. While the regional signatures exhibit clear distinctions, the limited sample sizes underscore the necessity for supplementary methods to confidently attribute timber to a specific source forest. In isolation, this method proves most effective in refuting presumed timber provenances rather than definitively confirming them. The discussion delves into the nuances of the Sr isotope data, emphasizing the importance of increasing the number of samples and exploring complementary techniques for a more comprehensive and reliable assessment of timber origin.

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Coffee is widely consumed across the globe. The most sought out varieties are Arabica and Robusta which differ significantly in their aroma and taste. Furthermore, varieties cultivated in different regions are perceived to have distinct characteristics encouraging some producers to adopt the denomination of origin label. These differences arise from variations on metabolite content related to edaphoclimatic conditions and post-harvest management among other factors. Although sensory analysis is still standard for coffee brews, instrumental analysis of the roasted and green beans to assess the quality of the final product has been encouraged. Metabolomic profiling has risen as a promising approach not only for quality purposes but also for geographic origin assignment. Many techniques can be applied for sample analysis: chromatography, mass spectrometry, and NMR have been explored. The data collected is further sorted by multivariate analysis to identify similar characteristics among the samples, reduce dimensionality and/or even propose a model for predictive purposes. This review focuses on the evolution of metabolomic profiling for the geographic origin assessment of roasted and green coffee beans in the last 21 years, the techniques that are usually applied for sample analysis and also the most common approaches for the multivariate analysis of the collected data. The prospect of applying a wide range of analytical techniques is becoming an unbiased approach to determine the origin of different roasted and green coffee beans samples with great correlation. Predictive models worked accurately for the geographic assignment of unknown samples once the variety was known.

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The assignment of individuals to a population can be of importance for the identification of mass disaster victims or criminal offenders in the field of forensic genetics. This assignment is based on biostatistical methods that process data of ancestry informative markers (AIMs), which are selected based on large allele frequency differences between the populations of interest. However, population assignments of individuals with an admixed genetic background are challenging. Admixed individuals are genetic mosaics of chromosomal segments from the parental populations, which may lead to ambiguous or no population assignment. This is problematic since admixture events are a substantial part of human history. In this study, we present challenges of interpreting the evidential weight of population assignments. We used Genogeographer for likelihood ratio (LR) calculations and Brazilians as examples of admixed individuals. Brazilians are a very heterogenous population representing a three-way admixture between Native Americans, Europeans, and Africans. Ancestry informative markers were typed in a total of 589 individuals from Brazil using the Precision ID Ancestry Panel. The Brazilians were assigned to six metapopulations (East Asia, Europe, Middle East, North Africa, South-Central Asia, Sub-Saharan Africa) defined in the Genogeographer software and LRs were calculated if the AIM profile was not an outlier in all metapopulations and simulated two-way (1:1) admixtures of the six metapopulations. Population assignments failed for 55% of the samples. These samples had significantly higher genetic contributions from East Asia, South-Central Asia and Sub-Saharan Africa, and significantly lower genetic contributions from Europe. Most of the individuals with population assignments were assigned to the metapopulations of Middle East (58%) or North Africa (36%), followed by Europe (4%), South-Central Asia (1%), and Sub-Saharan Africa (1%). For 8% of the samples, population assignments were only possible when assignments to simulated two-way (1:1) admixtures of the six metapopulations were considered. Most of these individuals were assigned to two-way admixtures of North Africa, South-Central Asia, or Sub-Saharan Africa. Relatively low median likelihood ratios (LRs<1000) were observed when comparing population likelihoods for Europe, Middle East, North Africa, South-Central Asia, or simulated 1:1 admixtures of these metapopulations. Comparisons including East Asian or Sub-Saharan African populations resulted in larger median LRs (LR>1010). The results suggested that the Precision ID Ancestry Panel provided too little information and that additional markers specifically selected for sub-continental differentiation may be required for accurate population assignment of admixed individuals. Furthermore, a Genogeographer database with additional populations including admixed populations would be advantageous for interpretation of admixed AIM profiles. It would likely increase the number of population assignments and illustrate alternatives to the most likely population, which would be valuable information for the case officer when writing the case report.

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Hepatitis E virus (HEV) circulation in humans and swine has been extensively studied in South America over the last two decades. Nevertheless, only 2.1% of reported HEV strains are available as complete genome sequences. Therefore, many clinical, epidemiological, and evolutionary aspects of circulating HEV in the continent still need to be clarified. Here, we conducted a retrospective evolutionary analysis of one human case and six swine HEV strains previously reported in northeastern, southern, and southeastern Brazil. We obtained two complete and four nearly complete genomic sequences. Evolutionary analysis comparing the whole genomic and capsid gene sequences revealed high genetic variability. This included the circulation of at least one unrecognized unique South American subtype. Our results corroborate that sequencing the whole capsid gene could be used as an alternative for HEV subtype assignment in the absence of complete genomic sequences. Moreover, our results substantiate the evidence for zoonotic transmission by comparing a larger genomic fragment recovered from the sample of the autochthonous human hepatitis E case. Further studies should continuously investigate HEV genetic diversity and zoonotic transmission of HEV in South America.

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Wireless cellular networks have become increasingly important in providing data access to cellular users via a grid of cells. Many applications are considered to read data from smart meters for potable water, gas, or electricity. This paper proposes a novel algorithm to assign paired channels for intelligent metering through wireless connectivity, which is particularly relevant due to the commercial advantages that a virtual operator currently provides. The algorithm considers the behavior of secondary spectrum channels assigned to smart metering in a cellular network. It explores spectrum reuse in a virtual mobile operator to optimize dynamic channel assignment. The proposed algorithm exploits the white holes in the cognitive radio spectrum and considers the coexistence of different uplink channels, resulting in improved efficiency and reliability for smart metering. The work also defines the average user transmission throughput and total smart meter cell throughput as metrics to measure performance, providing insights into the effects of the chosen values on the overall performance of the proposed algorithm.

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A transfusão de sangue é considerada uma tecnologia de grande importância na terapia moderna. Quando usada corretamente, pode salvar vidas e melhorar o quadro clínico dos pacientes. Todavia, esse procedimento pode apresentar riscos tanto aguda quanto tardia. Para tanto, o conhecimento da enfermagem é de grande relevância a fim de evitar complicações e fornecer um procedimento assertivo ao paciente. Objetivo: Demonstrar, a partir de uma revisão integrativa dos últimos quatro anos, a atribuição do enfermeiro no processo de hemotransfusão, descrevendo seu papel desde o acolhimento até a infusão dos hemoderivados. Métodos: Trata-se de uma revisão integrativa da literatura. Resultados e discussão: Para a seleção, 10 artigos científicos foram inclusos na revisão. As análises em nível de grupo mostraram que é de suma importância do conhecimento técnico e científico para a segurança do paciente. Considerações finais: O processo de hemotransfusão é de responsabilidade da enfermagem, incluindo cuidados minuciosos e atenção clínica por parte do enfermeiro, devendo ser amplamente divulgado e discutido para garantir atualização de conhecimento entre os profissionais que atuam em hemoterapia, para que possam realizar as práticas com segurança e prevenir a ocorrência de eventos adversos.

Blood transfusion is considered a technology of great importance in modern therapy. When used correctly, it can save lives and improve the condition of patients. However, this procedure may present both acute and late requirements. Therefore, nursing knowledge is of great encouragement in order to avoid complications and provide an assertive procedure to the patient. Objective: To demonstrate, based on an integrative review of the last four years, the attribution of nurses in the blood transfusion process, describing their role from reception to the infusion of blood products. Methods: This is an integrative literature review. Results and discussion: For the selection, 10 scientific articles were included in the review. The group-level analyzes appreciated that technical and scientific knowledge is of paramount importance for patient safety. Final considerations: The blood transfusion process is the responsibility of nursing, including meticulous care and clinical attention by the nurse, and should be widely publicized and discussed to ensure updating of knowledge among professionals who perform hemotherapy, so that they can carry out the practices safely and preventing the occurrence of adverse events.

La transfusión de sangre se considera una tecnología de gran importancia en la terapia moderna. Cuando se utiliza correctamente, puede salvar vidas y mejorar el estado de los pacientes. Sin embargo, este procedimiento puede presentar requisitos agudos y tardíos. Por lo tanto, los conocimientos de enfermería son de gran estímulo para evitar complicaciones y proporcionar un procedimiento asertivo al paciente. Objetivo: Demostrar, a partir de una revisión integradora de los últimos cuatro años, la atribución de enfermería en el proceso de transfusión sanguínea, describiendo su papel desde la recepción hasta la infusión de hemoderivados. Métodos: Se trata de una revisión bibliográfica integradora. Resultados y discusión: Para la selección se incluyeron en la revisión 10 artículos científicos. Los análisis a nivel de grupo apreciaron que el conocimiento técnico y científico es de suma importancia para la seguridad del paciente. Consideraciones finales: El proceso de transfusión sanguínea es responsabilidad de enfermería, incluyendo el cuidado meticuloso y la atención clínica por parte de la enfermera, y debe ser ampliamente divulgado y discutido para garantizar la actualización de conocimientos entre los profesionales que realizan hemoterapia, para que puedan llevar a cabo las prácticas con seguridad y previniendo la ocurrencia de eventos adversos. PALABRAS CLAVE: Hemoterapia; Transfusión Sanguínea; Infusión de Hemoderivados; Cuidados de Enfermería; Asignación de Enfermería.

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BACKGROUND: Neuregulins comprise a large family of growth factors containing an epidermal growth factor (EGF) domain. NRG1 acts in signaling pathways involved in proliferation, apoptosis, migration, differentiation, and adhesion of many normal cell types and in human diseases. The EGF domain of NRG1 mediates signaling by interaction with members of the ErbB family of receptors. Easy access to correctly folded hNRG1α EGF domain can be a valuable tool to investigate its function in different cell types. MATERIALS AND METHODS: The EGF domain of hNRG1α was produced in Escherichia coli in fusion with TrxA and purified after cleavage of TrxA. Conformation and stability analyses were performed by using biophysical methods and the disulfide bonds were mapped by mass spectrometry. The activity of the hNRG1α EGF domain was demonstrated in cell proliferation and migration assays. RESULTS: Approximately 3.3 mg of hNRG1α EGF domain were obtained starting from a 0.5 L of E. coli culture. Correct formation of the three disulfide bonds was demonstrated by mass spectrometry with high accuracy. Heat denaturation assays monitored by circular dichroism and dynamic light scattering revealed that it is a highly stable protein. The recombinant EGF domain of hNRG1α purified in this work is highly active, inducing cell proliferation at concentration as low as 0.05 ng/mL. It induces also cell migration as demonstrated by a gap closure assay. CONCLUSION: The EGF domain of hNRG1α was produced in E. coli with the correct disulfide bonds and presented high stimulation of HeLa cell proliferation and NDFH cell migration.

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Microbial communities' taxonomic and functional diversity has been broadly studied since sequencing technologies enabled faster and cheaper data obtainment. Nevertheless, the programming skills needed and the amount of software available may be overwhelming to someone trying to analyze these data. Here, we present a comprehensive and straightforward pipeline that takes shotgun metagenomics data through the needed steps to obtain valuable results. The raw data goes through a quality control process, metagenomic assembly, binning (the obtention of single genomes from a metagenome), taxonomic assignment, and taxonomic diversity analysis and visualization.

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Zika virus (ZIKV) emerged as a global public health concern due to its relationship with severe neurological disorders. Non-structural (NS) proteins of ZIKV are essential for viral replication, regulatory function, and subversion of host responses. NS2B is a membrane protein responsible for the regulation of viral protease activity. This protein has transmembrane domains critical for the localization of viral protease to the endoplasmic reticulum membrane and a hydrophilic domain essential for folding, recruitment, and protease activity. Therefore, NS2B is considered a cofactor of viral protease which processes viral polyprotein and is essential for virus replication, making it an attractive antiviral drug target. Here, we report the backbone 1H, 15N, 13C resonance assignments of the full-length NS2B by high-resolution NMR. The backbone assignment will be necessary for determining the three-dimensional structure and backbone dynamics of NS2B, interaction mapping and screening potential of antiviral drugs against ZIKV and related pathogenic flaviviruses.

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In this paper, a complete 1 H and 13 C NMR data assignment of ent-polyalthic acid, a biologically active labdane-type diterpene, is presented. The assignments were carried on the basis of spectroscopic data from 1 H NMR, 13 C{1 H} NMR, gCOSY, gHMQC, and gHMBC experiments. Furthermore, a software-assisted methodology, using FOMSC3_rm_NB and NMR_MultSim programs, supported the detailed and unequivocal assignment of 1 H and 13 C signals, allowing all hydrogen coupling constants to be determined and thus clarifying all hydrogen signal multiplicities.

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El trabajo de fonoaudiólogos (as) en contextos educativos es esencial para estudiantes que presentan necesidades educativas especiales. Sin embargo, poco se sabe respecto a cómo influye la asignación del tiempo otorgado por la política educativa en sus prácticas fonoaudiológicas. El presente estudio analizó por primera vez en Chile la experiencia de fonoaudiólogos (as) con más de 20 años de ejercicio laboral respecto de la asignación del tiempo definido por la política pública para la práctica fonoaudiológica que se lleva a cabo en los entornos educativos. Se realizó un estudio cualitativo con enfoque construccionista-narrativo. Se realizaron cinco entrevistas semiestructuradas a fonoaudiólogos con más de veinte años de experiencia laboral en educación a través de un análisis de contenido de tipo deductivo. Los resultados muestran que la práctica fonoaudiológica presenta desafíos provenientes de aspectos administrativos, organizativos y prácticos que surgen de una política pública que no define de manera clara la asignación de tiempo y su distribución en las funciones propias del rol fonoaudiológico en educación. El aporte de esta investigación pionera en la temática,es que los fonoaudiólogos entrevistados sugieren cambios a la política implementada a partir de los ajustes que han realizado en sus prácticas profesionales tras 20 años de experiencia laboral. Es necesario continuar en la investigación sobre el ejercicio del rol fonoaudiológico en contextos educativos con el fin de mejorar la práctica profesional y contribuir a la política educativa implementada.

Speech therapists' work in educational contexts is essential for students presenting special educational needs. However, little is known about the influence of the amount of time granted by educational policy in speech therapists' professional practice.The present study did the first analysis in Chile of the experience of speech therapists with over 20 years of professional experience regarding the amount of time defined in public policy for speech therapists' practice carried out in educational environments. A qualitative study with a constructionist-narrative focus was done. Five semi-structured interviews were carried out with speech therapists who had over 20 years' professional educational experience via an inductive-type content analysis. Results showed that speech therapists' practice presents challenges arising from administrative, organizational and practical aspects emerging from a public policy which does not clearly define time assignment and its distribution in the functions pertaining to speechtherapists' educational role. The contribution of this pioneering research on the subject is that the speech therapists interviewed suggest changes to the policy implemented on the basis of the adjustments they have made in their professional practices after 20 years of work experience. It is necessary to continue research on the exercise of the role of speech therapists in educational contexts in order to improve professional practice and contribute to the educational policy implemented.

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KIN is a DNA/RNA-binding protein conserved evolutionarily from yeast to humans and expressed ubiquitously in mammals. It is an essential nuclear protein involved in numerous cellular processes, such as DNA replication, class-switch recombination, cell cycle regulation, and response to UV or ionizing radiation-induced DNA damage. The C-terminal region of the human KIN (hKIN) protein is composed of an SH3-like tandem domain, which is crucial for the anti-proliferation effect of the full-length protein. Herein, we present the 1H, 15N, and 13C resonances assignment of the backbone and side chains for the SH3-like tandem domain of the hKIN protein, as well as the secondary structure prediction based on the assigned chemical shifts using TALOS-N software. This work prepares the ground for future studies of RNA-binding and backbone dynamics.

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Despite strong support from the media, the reintroduction of animals into natural environments does not always achieve its goal. Alouatta caraya is the primate species facing the greatest hunting pressure due to the illegal pet trade in Argentina. Confiscations of this species are common, as is the voluntary surrender of animals by owners no longer able or willing to care for them. These animals ultimately arrive at rehabilitation centers and, in many cases, are released into natural environments that may differ from the original sites where they were captured. Until recently, the lack of genetic analysis of the individuals involved led to biased relocation decisions. We followed the reintroduction of 12 A. caraya individuals in a protected area (Isla Palacio, Misiones, Argentina). The presence of potential predators such as pumas (Puma concolor) and jaguars (Panthera onca) in this area was confirmed by camera traps, footprints and feces. After the disappearance of four A. caraya at the reintroduction site, we investigated the applicability of genetic assignment tests based on genotypic data to accurately identify predated individuals. Genetic analyses allowed us to determine the predator species (P. onca) and to identify the predated individuals as two of the reintroduced animals. This procedure is promising for identifying the remains of predated individuals, and can contribute to the design of reintroduction policies based on scientific evidence.

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Coronaviruses have become of great medical and scientific interest because of the Covid-19 pandemic. The hCoV-HKU1 is an endemic betacoronavirus that causes mild respiratory symptoms, although the infection can progress to severe lung disease and death. During viral replication, a discontinuous transcription of the genome takes place, producing the subgenomic messenger RNAs. The nucleocapsid protein (N) plays a pivotal role in the regulation of this process, acting as an RNA chaperone and participating in the nucleocapsid assembly. The isolated N-terminal domain of protein N (N-NTD) specifically binds to the transcriptional regulatory sequences and control the melting of the double-stranded RNA. Here, we report the resonance assignments of the N-NTD of HKU1-CoV.

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A progressive paradigm shift from centralized to distributed network architectures has been consolidated since the 4G communication standard, calling for novel decision-making mechanisms with distributed control to operate at the network edge. This situation implies that each base station (BS) must manage resources independently to meet the quality of service (QoS) of existing human-type communication devices (HTC), as well as the emerging machine type communication (MTC) devices from the internet of things (IoT). In this paper, we address the BS assignment problem, whose aim is to determine the most appropriate serving BS to each mobile device. This problem is formulated as an optimization problem for maximizing the system throughput and imposing constraints on the air interface and backhaul resources. The assignment problem is challenging to solve, so we present a simple yet valid reformulation of the original problem while using dual decomposition theory. Subsequently, we propose a distributed price-based BS assignment algorithm that performs at each BS the assignment process, where a novel pricing update scheme is presented. The simulation results show that our proposed solution outperforms traditional maximum signal to interference plus noise ratio (Max-SINR) and minimum path-loss (Min-PL) approaches in terms of system throughput.

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Resumen Este documento tiene como finalidad identificar algunos problemas éticos de los procesos de atención en el contexto de la pandemia por SARS-CoV-2 en Colombia, y proponer un conjunto de principios y criterios éticos que permitan a las instituciones y los trabajadores de la salud la toma de decisiones éticamente sustentables y jurídicamente factibles, con un especial enfoque en la protección del núcleo de los derechos fundamentales de pacientes y trabajadores, en un contexto extraordinario caracterizado por la inequidad estructural y la discrepancia entre la oferta y la demanda de bienes, recursos y servicios de salud, con el objetivo de mitigar el estrés moral, maximizar los beneficios derivados de la utilización de los recursos escasos y modular los riesgos éticos y jurídicos asociados.(Acta Med Colomb 2020; 45. DOI:https://doi.org/10.36104/amc.2020.1952).

Abstract The purpose of this document is to identify some ethical problems in healthcare processes within the context of the SARS-CoV-2 pandemic in Colombia, and propose a collection of ethical principles and criteria which will allow healthcare institutions and workers to make ethically supported and legally feasible decisions. These decisions should especially focus on protecting the core of the fundamental rights of patients and workers, in an extraordinary context characterized by structural inequity and a discrepancy between the supply and demand of healthcare goods, resources and services. Ultimately, this will mitigate moral stress, maximize the benefits derived from the use of scarce resources, and modulate the associated ethical and legal risks.(Acta Med Colomb 2020; 45. DOI:https://doi.org/10.36104/amc.2020.1952).

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Dipteryx timber has been heavily exploited in South America since 2000s due to the increasing international demand for hardwood. Developing tools for the genetic identification of Dipteryx species and their geographical origin can help to promote legal trading of timber. A collection of 800 individual trees, belonging to 6 different Dipteryx species, was genotyped based on 171 molecular markers. After the exclusion of markers out of Hardy-Weinberg equilibrium or with no polymorphism or low amplification, 83 nuclear, 29 chloroplast, 13 mitochondrial single nucleotide polymorphisms (SNPs), and 2 chloroplast and 5 mitochondrial INDELS remained. Six genetic groups were identified using Bayesian Structure analyses of the nuclear SNPs, which corresponded to the different Dipteryx species collected in the field. Seventeen highly informative markers were identified as suitable for species identification and obtained self-assignment success rates to species level of 78-96%. An additional set of 15 molecular markers was selected to determine the different genetic clusters found in Dipteryx odorata and Dipteryx ferrea, obtaining self-assignment success rates of 91-100%. The success to assign samples to the correct country of origin using all or only the informative markers improved when using the nearest neighbor approach (69-92%) compared to the Bayesian approach (33-80%). While nuclear and chloroplast SNPs were more suitable for differentiating the different Dipteryx species, mitochondrial SNPs were ideal for determining the genetic clusters of D. odorata and D. ferrea. These 32 selected SNPs will be invaluable genetic tools for the accurate identification of species and country of origin of Dipteryx timber.

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The codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is a major pest introduced to almost all main pome fruit production regions worldwide. This species was detected in Chile during the last decade of the 19th century, and now has a widespread distribution in all major apple-growing regions. We performed an analysis of the genetic variability and structure of codling moth populations in Chile using five microsatellite markers. We sampled the codling moth along the main distribution area in Chile on all its main host-plant species. Low genetic differentiation among the population samples (FST = 0.03) was found, with only slight isolation by distance. According to a Bayesian assignment test (TESS), a group of localities in the coastal mountain range from the Bío-Bío Region formed a distinct genetic cluster. Our results also suggest that the codling moth that invaded the southernmost locality (Aysén Region) had two origins from central Chile and another unknown source. We did not find significant genetic differentiation between codling moth samples from different host-plant species. Our results indicate high genetic exchange among codling moth populations between the different Chilean regions and host plants.

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In this study, we describe seven vegetative phage genomes homologous to the historic phage B3 that infect Pseudomonas aeruginosa Like other phage groups, the B3-like group contains conserved (core) and variable (accessory) open reading frames (ORFs) grouped at fixed regions in their genomes; however, in either case, many ORFs remain without assigned functions. We constructed lysogens of the seven B3-like phages in strain Ps33 of P. aeruginosa, a novel clinical isolate, and assayed the exclusion phenotype against a variety of temperate and virulent superinfecting phages. In addition to the classic exclusion conferred by the phage immunity repressor, the phenotype observed in B3-like lysogens suggested the presence of other exclusion genes. We set out to identify the genes responsible for this exclusion phenotype. Phage Ps56 was chosen as the study subject since it excluded numerous temperate and virulent phages. Restriction of the Ps56 genome, cloning of several fragments, and resection of the fragments that retained the exclusion phenotype allowed us to identify two core ORFs, so far without any assigned function, as responsible for a type of exclusion. Neither gene expressed separately from plasmids showed activity, but the concurrent expression of both ORFs is needed for exclusion. Our data suggest that phage adsorption occurs but that phage genome translocation to the host's cytoplasm is defective. To our knowledge, this is the first report on this type of exclusion mediated by a prophage in P. aeruginosaIMPORTANCEPseudomonas aeruginosa is a Gram-negative bacterium frequently isolated from infected immunocompromised patients, and the strains are resistant to a broad spectrum of antibiotics. Recently, the use of phages has been proposed as an alternative therapy against multidrug-resistant bacteria. However, this approach may present various hurdles. This work addresses the problem that pathogenic bacteria may be lysogenized by phages carrying genes encoding resistance against secondary infections, such as those used in phage therapy. Discovering phage genes that exclude superinfecting phages not only assigns novel functions to orphan genes in databases but also provides insight into selection of the proper phages for use in phage therapy.

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