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Anabaena sp. PCC7120 possesses three genes coding for single-stranded DNA-binding ( SSB) protein, of which ssb1 was a single gene, and ssb2 and ssb3 are the first genes of their corresponding operons. Regulation of the truncated ssb genes, ssb1 ( alr0088) and ssb2 ( alr7559), was unaffected by N-status of growth. They were negatively regulated by the SOS-response regulatory protein LexA, as indicated by the (i) binding of Anabaena LexA to the LexA box of regulatory regions of ssb1 and ssb2, and (ii) decreased expression of the downstream gfp reporter gene in Escherichia coli upon co-expression of LexA. However, the full-length ssb gene, ssb3 ( all4779), was regulated by the availability of Fe2+ and combined nitrogen, as indicated by (i) increase in the levels of SSB3 protein on Fe2+-depletion and decrease under Fe2+-excess conditions, and (ii) 1.5- to 1.6-fold decrease in activity under nitrogen-fixing conditions compared to nitrogen-supplemented conditions. The requirement of Fe2+ as a co-factor for repression by FurA and the increase in levels of FurA under nitrogen-deficient conditions in Anabaena (Lopez-Gomollon et al. 2007) indicated a possible regulation of ssb3 by FurA. This was substantiated by (i) the binding of FurA to the regulatory region of ssb3, (ii) repression of the expression of the downstream gfp reporter gene in E. coli upon co-expression of FurA, and (iii) negative regulation of ssb3 promoter activity by the upstream AT-rich region in Anabaena. This is the first report on possible role of FurA, an important protein for iron homeostasis, in DNA repair of cyanobacteria. [ABSTRACT FROM AUTHOR]

A bacterial endosymbiont was unexpectedly found in the 'axenic' culture strain of the streptophyte green alga Mesostigma viride ( NIES-995). Phylogenetic analyses based on 16S rRNA gene sequences showed that the symbiont belongs to the order Rickettsiales, specifically to the recently designated clade ' Candidatus Megaira,' which is closely related to the well-known Rickettsia clade. Rickettsiales bacteria of the ' Ca. Megaira' clade are found in a taxonomically diverse array of eukaryotic hosts, including chlorophycean green algae, several ciliate species, and invertebrates such as Hydra. Transmission electron microscopy, fluorescence in situ hybridi-zation, and SYBR Green I staining experiments revealed that the endosymbiont of M. viride NIES-995 is rod shaped, typically occurs in clusters, and is surrounded by a halo-like structure, presumably formed by secretory substances from the bacterium. Two additional M. viride strains ( NIES-296 and NIES-475), but not SAG50-1, were found to house the rickettsial endosymbiont. Analyses of strain NIES-995 transcriptome data indicated the presence of at least 91 transcriptionally active genes of symbiont origins. These include genes for surface proteins (e.g., rOmpB) that are known to play key roles in bacterial attachment onto host eukaryotes in related Rickettsia species. The assembled M. viride transcriptome includes transcripts that code for a suite of predicted algal-derived proteins, such as Ku70, WASH, SCAR, and CDC42, which may be important in the formation of the algal-rickettsial association. [ABSTRACT FROM AUTHOR]

Electron backscatter diffraction and confocal laser microscopy have been used to quantify the degree of crystallographic anisotropy during corrosion of AISI 316L in two test solutions. Corrosion in 30 vol% H2SO4 sulphuric acid shows pronounced crystallographic anisotropy in which the corrosion rate increases in the order {111} < {110} ≲ {100}. The ratio between the slowest corroding {111} and the fasting corroding {100} surfaces is about 3. Pitting corrosion in a solution of FeCl3 and AlCl3 in ethanol/glycerol agrees with other reported observations that high-atomic density surfaces {111} and {100} are less prone to pit nucleation, however the effect was relative small. [ABSTRACT FROM AUTHOR]

Algal blooms are a worldwide phenomenon and the biological interactions that underlie their regulation are only just beginning to be understood. It is established that algal microorganisms associate with many other ubiquitous, oceanic organisms, but the interactions that lead to the dynamics of bloom formation are currently unknown. To address this gap, we used network approaches to investigate the association patterns among microeukaryotes and bacterioplankton in response to a natural Scrippsiella trochoidea bloom. This is the first study to apply network approaches to bloom dynamics. To this end, terminal restriction fragment (T-RF) length polymorphism analysis showed dramatic changes in community compositions of microeukaryotes and bacterioplankton over the blooming period. A variance ratio test revealed significant positive overall associations both within and between microeukaryotic and bacterioplankton communities. An association network generated from significant correlations between T-RFs revealed that S. trochoidea had few connections to other microeukaryotes and bacterioplankton and was placed on the edge. This lack of connectivity allowed for the S. trochoidea sub-network to break off from the overall network. These results allowed us to propose a conceptual model for explaining how changes in microbial associations regulate the dynamics of an algal bloom. In addition, key T-RFs were screened by principal components analysis, correlation coefficients, and network analysis. Dominant T-RFs were then identified through 18S and 16S rRNA gene clone libraries. Results showed that microeukaryotes clustered predominantly with Dinophyceae and Perkinsea while the majority of bacterioplankton identified were Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes. The ecologi-cal roles of both were discussed in the context of these findings. [ABSTRACT FROM AUTHOR]

Three populations of the freshwater filamentous cyanobacterium Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck have been putatively identified from north-eastern Australia and found to produce the potent cyanotoxin cylindrospermopsin ( CYN) and its analog deoxy-cylindrospermopsin (deoxy- CYN). We investigated the phylogeny and toxicology of strains and mats isolated from two of these populations using a combination of molecular and morphological techniques. Morphologically the strains corresponded to the type description, however, the frequency of false-branching was low, and variable over time. Strains and mat samples from both sites were positive for the cyrF and cyrJ genes associated with CYN biosynthesis. Phylogenetic analysis of these genes from Australian L. wollei sequences and comparable cyanobacterial sequences revealed that the genes in L. wollei were more closely related to homologous genes in Oscillatoria sp. PCC 6506 than to homologs in Nostocalean CYN-producers. These data suggest a common evolutionary origin of CYN biosynthesis in L. wollei and Oscillatoria. In both the 16S rRNA and nifH phylogenies, the Australian L. wollei strains formed well-supported clades with United States L. wollei (= Plectonema wollei) strains. Pair-wise sequence similarities within the 16S rRNA clade containing all eleven L. wollei strains were high, ranging from 97% to 100%. This group was distantly related (<92% nucleotide similarity) to other taxa within the group previously considered under the genus Lyngbya sensu lato (C. Agardh ex Gomont). Collectively, these results suggest that this toxigenic group is evolutionarily distinct and sufficiently distant as to be considered a separate genus, which we have described as Microseira gen. nov. and hence transfer to it the type M. wollei comb. nov. [ABSTRACT FROM AUTHOR]

Anabaena sp. PCC7120 possesses three genes coding for single-stranded DNA-binding ( SSB) protein, of which ssb1 was a single gene, and ssb2 and ssb3 are the first genes of their corresponding operons. Regulation of the truncated ssb genes, ssb1 ( alr0088) and ssb2 ( alr7559), was unaffected by N-status of growth. They were negatively regulated by the SOS-response regulatory protein LexA, as indicated by the (i) binding of Anabaena LexA to the LexA box of regulatory regions of ssb1 and ssb2, and (ii) decreased expression of the downstream gfp reporter gene in Escherichia coli upon co-expression of LexA. However, the full-length ssb gene, ssb3 ( all4779), was regulated by the availability of Fe2+ and combined nitrogen, as indicated by (i) increase in the levels of SSB3 protein on Fe2+-depletion and decrease under Fe2+-excess conditions, and (ii) 1.5- to 1.6-fold decrease in activity under nitrogen-fixing conditions compared to nitrogen-supplemented conditions. The requirement of Fe2+ as a co-factor for repression by FurA and the increase in levels of FurA under nitrogen-deficient conditions in Anabaena (Lopez-Gomollon et al. 2007) indicated a possible regulation of ssb3 by FurA. This was substantiated by (i) the binding of FurA to the regulatory region of ssb3, (ii) repression of the expression of the downstream gfp reporter gene in E. coli upon co-expression of FurA, and (iii) negative regulation of ssb3 promoter activity by the upstream AT-rich region in Anabaena. This is the first report on possible role of FurA, an important protein for iron homeostasis, in DNA repair of cyanobacteria. [ABSTRACT FROM AUTHOR]

Cyanobacterial distributions are shaped by abiotic factors including temperature, light and nutrient availability as well as biotic factors such as grazing and viral infection. In this study, we investigated the abundances of T4-like and T7-like cyanophages and the extent of picocyanobacterial infection in the cold, high-nutrient-low-chlorophyll, sub-Antarctic waters of the southwest Pacific Ocean during austral spring. Synechococcus was the dominant picocyanobacterium, ranging from 4.7 × 10 3 to 1.2 × 10 5 cells∙mL -1 , while Prochlorococcus abundances were relatively low overall, ranging from 1.0 × 10 3 to 3.9 × 10 4 cells∙mL -1 . Using taxon-specific, single-virus and single-cell polony methods, we found that cyanophages were on average 15-fold, and up to 50-fold, more abundant than cyanobacteria in these waters. T4-like cyanophages (ranging from 1.7 × 10 5 to 6.5 × 10 5 phage·mL -1 ) were 2.7-fold more abundant than T7-like cyanophages (ranging from 3.1 × 10 4 to 2.8 × 10 5 phage·mL -1 ). Picocyanobacteria were primarily infected by T4-like cyanophages with more Synechococcus (4.8%-12.1%) infected than Prochlorococcus (2.5%-6.2%), whereas T7-like cyanophages infected less than 1% of both genera. These infection levels translated to daily mortality in the range of 5.7%-26.2% and 2.9%-14.3% of the standing stock of Synechococcus and Prochlorococcus, respectively. Our findings suggest that T4-like cyanophages are significant agents of cyanobacterial mortality in the cold, low-iron, sub-Antarctic waters of the South Pacific Ocean., (© 2025 The Author(s). Environmental Microbiology published by John Wiley & Sons Ltd.)

Synechococcus is a significant primary producer in the oceans, coexisting with cyanophages, which are important agents of mortality. Bacterial resistance against phage infection is a topic of significant interest, yet little is known for ecologically relevant systems. Here we use exogenous gene expression and gene disruption to investigate mechanisms underlying intracellular resistance of marine Synechococcus WH5701 to the Syn9 cyanophage. The restriction-modification and Gabija defence systems possessed by Synechococcus WH5701 did not contribute to resistance. Instead, resistance was primarily driven by insufficient levels of Leu TAA tRNA, preventing translation of key phage genes in a passive, intracellular mode of resistance. Restoring cellular tRNA expression rendered the cyanobacterium sensitive to infection. We propose an evolutionary scenario whereby changes in cell codon usage, acquisition of tRNAs by the phage and loss of cell and phage tRNA expression resulted in an effective means of resistance, highlighting the dynamic interplay between bacteria and phages in shaping their co-evolutionary trajectories., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background: A nurse's perspective is unique and invaluable to health policy. Although political astuteness is essential for nurses and nurse educators to be effective participants in health policy, there is a gap in the nursing literature on civic knowledge and its potential relationship to political astuteness., Purpose: This research aimed to assess the civic knowledge and self-reported political astuteness of academic nurse educators, their associated factors, and the relationship between these two concepts., Methods: This cross-sectional study used a national sample of academic nurse educators who answered 10 questions taken from the United States Citizenship and Immigration Services (USCIS) Naturalization test and completed the Political Astuteness Inventory (PAI)., Results: Over 51 % of the sample (n = 122) did not provide enough correct answers to pass the Naturalization test and over 35 % were determined to be either completely or slightly unaware politically. There was a medium positive correlation (r = 0.313, p < .001) between civic knowledge and self-reported political astuteness., Conclusion: Although nurse educators could be well-positioned to impact health policy, they may not have the knowledge or skills to fulfill this potential. Strategies for improving political astuteness include increasing civic knowledge and encouraging professional collaboration to promote nursing solidarity, influence, and power., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to disclose., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Introduction: Individuals with serious mental illness often have persistent and disruptive symptoms. These can profoundly affect their children's lives, exposing them to adverse social and psychological conditions. Such conditions can result in traumatic lived experiences during childhood, which can carry over into adulthood, influencing their self-perceptions and shaping their attitudes toward themselves and society. To gain insights into this phenomenon, this study explored the lived experiences of adults who grew up with a parent with serious mental illness and their perceptions of their lives in adulthood., Design: This study used an interpretive phenomenological design., Methods: Participants were invited to voluntarily participate in the study through a call posted on social media. Semi-structured interviews were conducted with 30 adults (age range, 20-55 years) who grew up with a parent with serious mental illness. The interviews were recorded and transcribed, and inductive thematic analysis was used to identify main and overarching themes., Results: The overarching theme of transition from childhood survival to adulthood survival emerged and included four main themes: (1) a traumatic childhood, (2) perceived control, (3) resilience and general self-efficacy, and (4) adult quality of life. A traumatic childhood consisted of experiences of neglect and abuse, while participants used perceived control to achieve personal growth, self-care, and care of others. Resilience and general self-efficacy emerged during the transition to adulthood and helped participants further their social status and strengthen family bonds. Lastly, adult quality of life was described as being disturbed by feelings of loneliness and being burdensome, stemming from an inherent tendency to rely solely on themselves, leading to trust issues and mental health complications. Therefore, these adults found it difficult to reach out and get help or treatment for their concerns, as they initially did not want to appear dysfunctional or in need., Conclusion: This study has illuminated the lived experiences of a specific, vulnerable population that has not been intentionally explored until now. To delve into these experiences, we employed a distinctive qualitative approach, merging the interpretive phenomenological perspective with an inductive thematic analysis. This allowed for rich insight with a relatively large group of participants and enabled an in-depth exploration within this methodological framework. Consequently, this study constitutes a notable contribution to the extant body of knowledge, exploring the intricacies of personal growth and its impact on participants' quality of life. It uncovers the essence of resilience and general self-efficacy, revealing how these elements intertwine with the negative results observed. However, the study findings emphasize the need for healthcare professionals, including nurses and other caregivers, to be mindful of the long-lasting effects of the adverse experiences of children of patients with serious mental illness. Prioritizing active clinical assessment and implementing tailored interventions to address such children's specific needs and difficulties across different developmental stages is imperative. Such comprehensive and targeted approaches are crucial in providing appropriate support and promoting the well-being of these individuals., Clinical Relevance: Enhanced clinical attention in holistic psychiatric care is crucial for individuals and their relatives, especially children. Comprehensive assessments of children and adults raised by seriously mentally ill parents can enable tailored and preventive interventions, positively impacting overall quality of life., (© 2024 The Authors. Journal of Nursing Scholarship published by Wiley Periodicals LLC on behalf of Sigma Theta Tau International.)

Photosynthesis fuels primary production at the base of marine food webs. Yet, in many surface ocean ecosystems, diel-driven primary production is tightly coupled to daily loss. This tight coupling raises the question: which top-down drivers predominate in maintaining persistently stable picocyanobacterial populations over longer time scales? Motivated by high-frequency surface water measurements taken in the North Pacific Subtropical Gyre (NPSG), we developed multitrophic models to investigate bottom-up and top-down mechanisms underlying the balanced control of Prochlorococcus populations. We find that incorporating photosynthetic growth with viral- and predator-induced mortality is sufficient to recapitulate daily oscillations of Prochlorococcus abundances with baseline community abundances. In doing so, we infer that grazers in this environment function as the predominant top-down factor despite high standing viral particle densities. The model-data fits also reveal the ecological relevance of light-dependent viral traits and non-canonical factors to cellular loss. Finally, we leverage sensitivity analyses to demonstrate how variation in life history traits across distinct oceanic contexts, including variation in viral adsorption and grazer clearance rates, can transform the quantitative and even qualitative importance of top-down controls in shaping Prochlorococcus population dynamics., (© 2024. The Author(s).)

Second victim phenomenon (SVP) occurs when nurses who are involved in an unanticipated adverse event become victimized and traumatized by the event. Following a needs assessment, an SVP education program was implemented, including adverse events and SVP experiences, available support, and a case study. Evaluation indicated nurses had improved knowledge and attitude and increased practice intent. Education that promotes awareness is the first step to support nurses who experience events that can precipitate SVP., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: There is a gap in evidence for effective clinical teaching strategies to promote nursing students' development of clinical judgment (CJ)., Purpose: This study examined the effect of active learning strategies (ALSs) during clinical postconference sessions on the CJ of undergraduate nursing students., Methods: This quasi-experimental study of ALSs or standard postconferences used the Lasater Clinical Judgment Rubric (LCJR) to rate CJ at 3 time points. All faculty members and students were trained on use of the LCJR. Ratings were done by both faculty and students., Results: All ratings of CJ improved over time ( P < .001). Ratings of CJ varied between the control and intervention groups., Conclusions: The findings of this study contribute to knowledge regarding the effectiveness of clinical teaching strategies for CJ and preparation for entry to nursing practice., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Health disparities in lesbian, gay, bisexual, transgender, queer and other sexual and gender minority (LGBTQ+) individuals are well documented, and there is a dearth of primary care providers (PCPs) with the knowledge, skills, and attitudes to sensitively care for this diverse population., Purpose: The purpose of this research study was to ask LGBTQ+ patients what qualities they prefer in their PCP. The findings will be used to better prepare nurse practitioners (NPs) to care for this diverse community and inform the training of future NPs to provide patient-centered care to LGBTQ+ individuals., Methodology: In this qualitative descriptive study, four focus groups were conducted remotely between December 2020 and January 2021 with self-identified LGBTQ+ patients of an LGBTQ+ health center in the northeast. Thematic analysis of the data elicited codes, categories, and themes. Strategies were implemented to promote trustworthiness of the results., Results: Twenty-eight participants shared the qualities they value in their PCP. Analysis revealed four themes: "Ditch the white coats"; "Meet me where I am"; "The relationship is key"; and "Be knowledgeable about and comfortable with LGBTQ+ people and their health care needs.", Conclusions: The focus groups elucidated important information on caring for the LGTBQ+ communities and insights into what NPs must do to provide patient-centered care to this diverse population., Implications: These findings can improve practice through a better understanding of LGBTQ+ patients' perspectives. Additionally, this study demonstrates the feasibility of directly asking our patients what they want in their health care provider., Competing Interests: Competing interests: The authors report no conflicts of interest., (Copyright © 2022 American Association of Nurse Practitioners.)

Ocean ecosystems are inhabited by a diverse set of viruses that impact microbial mortality and evolution. However, the distribution and abundances of specific viral lineages, particularly those from the large bank of rare viruses, remains largely unknown. Here, we assessed the diversity and abundance of the TIM5-like cyanophages. The sequencing of three new TIM5-like cyanophage genomes and environmental amplicons of a signature gene from the Red Sea revealed highly conserved gene content and sequence similarity. We adapted the polony method, a solid-phase polymerase chain reaction assay, to quantify TIM5-like cyanophages during three 2000 km expeditions in the Pacific Ocean and four annual cycles in the Red Sea. TIM5-like cyanophages were widespread, detected at all latitudes and seasons surveyed throughout the photic zone. Yet they were generally rare, ranging between <100 and 4000 viruses·ml -1 . Occasional peaks in abundance of 10- to 100-fold were observed, reaching 71,000 viruses·ml -1 . These peaks were ephemeral and seasonally variable in the Red Sea. Infection levels, quantified during one such peak, were very low. These characteristics of low diversity and abundance, as well as variable outbreaks, distinguishes the TIM5-like lineage from other major cyanophage lineages and illuminates that rare virus lineages can be persistent and widespread in the oceans., (© 2022 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.)

Environmental virus communities are highly diverse. However, the infection physiology underlying the evolution of diverse phage lineages and their ecological consequences are largely unknown. T7-like cyanophages are abundant in nature and infect the marine unicellular cyanobacteria, Synechococcus and Prochlorococcus, important primary producers in the oceans. Viruses belonging to this genus are divided into two distinct phylogenetic clades: clade A and clade B. These viruses have narrow host-ranges with clade A phages primarily infecting Synechococcus genotypes, while clade B phages are more diverse and can infect either Synechococcus or Prochlorococcus genotypes. Here we investigated infection properties (life history traits) and environmental abundances of these two clades of T7-like cyanophages. We show that clade A cyanophages have more rapid infection dynamics, larger burst sizes and greater virulence than clade B cyanophages. However, clade B cyanophages were at least 10-fold more abundant in all seasons, and infected more cyanobacteria, than clade A cyanophages in the Red Sea. Models predicted that steady-state cyanophage abundances, infection frequency, and virus-induced mortality, peak at intermediate virulence values. Our findings indicate that differences in infection properties are reflected in virus phylogeny at the clade level. They further indicate that infection properties, together with differences in subclade diversity and host repertoire, have important ecological consequences with the less aggressive, more diverse virus clade having greater ecological impacts., (© 2022. The Author(s).)

The photosynthetic picocyanobacteria Prochlorococcus and Synechococcus are models for dissecting how ecological niches are defined by environmental conditions, but how interactions with bacteriophages affect picocyanobacterial biogeography in open ocean biomes has rarely been assessed. We applied single-virus and single-cell infection approaches to quantify cyanophage abundance and infected picocyanobacteria in 87 surface water samples from five transects that traversed approximately 2,200 km in the North Pacific Ocean on three cruises, with a duration of 2-4 weeks, between 2015 and 2017. We detected a 550-km-wide hotspot of cyanophages and virus-infected picocyanobacteria in the transition zone between the North Pacific Subtropical and Subpolar gyres that was present in each transect. Notably, the hotspot occurred at a consistent temperature and displayed distinct cyanophage-lineage composition on all transects. On two of these transects, the levels of infection in the hotspot were estimated to be sufficient to substantially limit the geographical range of Prochlorococcus. Coincident with the detection of high levels of virally infected picocyanobacteria, we measured an increase of 10-100-fold in the Synechococcus populations in samples that are usually dominated by Prochlorococcus. We developed a multiple regression model of cyanophages, temperature and chlorophyll concentrations that inferred that the hotspot extended across the North Pacific Ocean, creating a biological boundary between gyres, with the potential to release organic matter comparable to that of the sevenfold-larger North Pacific Subtropical Gyre. Our results highlight the probable impact of viruses on large-scale phytoplankton biogeography and biogeochemistry in distinct regions of the oceans., (© 2022. The Author(s).)

Marine cyanobacteria of the genera Synechococcus and Prochlorococcus are the most abundant photosynthetic organisms on earth, spanning vast regions of the oceans and contributing significantly to global primary production. Their viruses (cyanophages) greatly influence cyanobacterial ecology and evolution. Although many cyanophage genomes have been sequenced, insight into the functional role of cyanophage genes is limited by the lack of a cyanophage genetic engineering system. Here, we describe a simple, generalizable method for genetic engineering of cyanophages from multiple families, that we named REEP for REcombination, Enrichment and PCR screening. This method enables direct investigation of key cyanophage genes, and its simplicity makes it adaptable to other ecologically relevant host-virus systems. T7-like cyanophages often carry integrase genes and attachment sites, yet exhibit lytic infection dynamics. Here, using REEP, we investigated their ability to integrate and maintain a lysogenic life cycle. We found that these cyanophages integrate into the host genome and that the integrase and attachment site are required for integration. However, stable lysogens did not form. The frequency of integration was found to be low in both lab cultures and the oceans. These findings suggest that T7-like cyanophage integration is transient and is not part of a classical lysogenic cycle., (© 2021. The Author(s).)

Advances in metagenomics have revealed the ubiquity of single-stranded DNA (ssDNA) phage belonging to the subfamily Gokushovirinae in the oceans; however, the abundance and ecological roles of this group are unknown. Here, we quantify gokushoviruses through adaptation of the polony method, in which viral template DNA is immobilized in a gel, amplified by PCR, and subsequently detected by hybridization. Primers and probes for this assay were designed based on PCR amplicon diversity of gokushovirus major capsid protein gene sequences from a depth profile in the Gulf of Aqaba, Red Sea sampled in September 2015. At ≥95% identity, these 87 gokushovirus sequences formed 14 discrete clusters with the largest clades showing distinct depth distributions. The application of the polony method enabled the first quantification of gokushoviruses in any environment. The gokushoviruses were most abundant in the upper 40 m of the stratified water column, with a subsurface peak in abundance of 1.26 × 10 5 viruses ml -1 . These findings suggest that discrete gokushovirus genotypes infect bacterial hosts that differentially partition in the water column. Since the designed primers and probe are conserved across marine ecosystems, this polony method can be applied broadly for the quantification of gokushoviruses throughout the global oceans., (© 2021 Society for Applied Microbiology and John Wiley & Sons Ltd.)

Long-term stability of picocyanobacteria in the open oceans is maintained by a balance between synchronous division and death on daily timescales. Viruses are considered a major source of microbial mortality, however, current methods to measure infection have significant methodological limitations. Here we describe a method that pairs flow-cytometric sorting with a PCR-based polony technique to simultaneously screen thousands of taxonomically resolved individual cells for intracellular virus DNA, enabling sensitive, high-throughput, and direct quantification of infection by different virus lineages. Under controlled conditions with picocyanobacteria-cyanophage models, the method detected infection throughout the lytic cycle and discriminated between varying infection levels. In North Pacific subtropical surface waters, the method revealed that only a small percentage of Prochlorococcus (0.35-1.6%) were infected, predominantly by T4-like cyanophages, and that infection oscillated 2-fold in phase with the diel cycle. This corresponds to 0.35-4.8% of Prochlorococcus mortality daily. Cyanophages were 2-4-fold more abundant than Prochlorococcus, indicating that most encounters did not result in infection and suggesting infection is mitigated via host resistance, reduced phage infectivity and inefficient adsorption. This method will enable quantification of infection for key microbial taxa across oceanic regimes and will help determine the extent that viruses shape microbial communities and ecosystem level processes.

The North Pacific Subtropical Gyre (NPSG) is one of the largest biomes on Earth, with the cyanobacterium Prochlorococcus being the most abundant primary producer year-round. Viruses that infect cyanobacteria (cyanophages) influence cyanobacterial mortality, diversity and evolution. Two major cyanophage families are the T4-like cyanomyoviruses and T7-like cyanopodoviruses, yet their abundances and distribution patterns remain unknown due to difficulty in quantifying their populations. To address this limitation, we previously adapted the polony method (for PCR colony) to quantify T7-like cyanophages and applied it to spring populations in the Red Sea. Here, we further adapted the method for the quantification of T4-like cyanophages and analyzed the abundances of T4-like and T7-like cyanophage populations in the photic zone of the NPSG in summer 2015 and spring 2016. Combined, the peak abundances of these two cyanophage families reached 2.8 × 10 6 and 1.1 × 10 6 cyanophages ⋅ ml -1 in the summer and spring, respectively. They constituted between 3 and 16% of total virus-like particles (VLPs), comprising a substantial component of the virioplankton in the NPSG. While both cyanophage families were highly abundant, the T4-like cyanophages were generally 1.3-4.4 fold more so. In summer, cyanophages had similar and reproducible distribution patterns with depth. Abundances were relatively low in the upper mixed layer and increased to form a pronounced subsurface peak at 100 m (1.9 × 10 6 and 9.1 × 10 5 phages ⋅ ml -1 for the T4-like and T7-like cyanophages, respectively), coincident with the maximum in Prochlorococcus populations. Less vertical structure in cyanophage abundances was apparent in the spring profile, despite a subsurface peak in Prochlorococcus numbers. In the summer upper mixed layer, cyanophages constituted a smaller proportion of VLPs than below it and cyanophage to cyanobacteria ratios were considerably lower (1.3-2.8) than those of VLPs to bacteria (8.1-21.2). Differences in abundances between the two families and their contribution to VLPs with depth suggest differences in cyanophage production and/or decay processes relative to other members of the virioplankton in the upper mixed layer. These findings highlight the importance of quantifying distinct populations within the virioplankton to gain accurate understanding of their distribution patterns., (Copyright © 2020 Goldin, Hulata, Baran and Lindell.)

Introduction: The learning environment refers to the physical, pedagogical, and psychosocial contexts in which learning occurs and critically influences the educational experience of trainees in the health professions. However, the manner in which individual faculty explicitly organize the educational setting to facilitate learning of essential competencies such as critical thinking deserves more examination; lack of attention to this component can undermine the formal curriculum. The purpose of our study was to examine how faculty shape the learning environment to advance their learners' development of critical thinking., Methods: We took a constructivist grounded theory approach using the framework method for qualitative content analysis. Data were derived from interviews conducted with 44 faculty identified as skilled teachers of critical thinking at eight academic health professions institutions., Results: Three major themes emerged regarding participants' descriptions of their experiences of how they optimized the learning environment to support critical thinking: 1) Setting the atmosphere (establishing ground rules, focusing on process rather than answers, and building trust), 2) Maintaining the climate (gently pushing learners, tolerating discomfort, and adjusting to learner level), and 3) Weathering the storm (responses to challenges to learning critical thinking, including time and effort, negative evaluations, and resistance to effortful learning)., Discussion: An optimal learning environment for critical thinking was actively created by faculty to establish a safe environment and shared understanding of expectations. Understanding how to produce a conducive learning climate is paramount in teaching essential topics such as critical thinking. These findings have potential utility for faculty development initiatives to optimize the learning environment.

Background: Certification is one option for validating the professional competence of academic nurse educators. The relative value associated with such certification has not yet been established., Method: Psychometric analysis of a new Perceived Value of Certification Tool for Academic Nurse Educators (PVCT-ANE) was conducted. Certified nurse educators (CNE) and noncertified nurse educators and nursing program administrators responded to an online survey using the PVCT-ANE., Results: A sample of 718 nurse faculty members and administrators from 48 states in the United States participated. Academic nurse educator certification was valued by nurse educators and administrators as representing specialized knowledge, attainment of a professional standard, educator competence, and professional credibility. Value statements associated with satisfaction and professional accomplishments were rated higher than statements associated with professional recognition and marketing., Conclusion: The PVCT-ANE is useful for assessing how different groups perceive the value associated with academic nurse educator certification. [J Nurs Educ. 2019;58(9):502-509.]., (Copyright 2019, SLACK Incorporated.)

Long-term coexistence between unicellular cyanobacteria and their lytic viruses (cyanophages) in the oceans is thought to be due to the presence of sensitive cells in which cyanophages reproduce, ultimately killing the cell, while other cyanobacteria survive due to resistance to infection. Here, we investigated resistance in marine cyanobacteria from the genera Synechococcus and Prochlorococcus and compared modes of resistance against specialist and generalist cyanophages belonging to the T7-like and T4-like cyanophage families. Resistance was extracellular in most interactions against specialist cyanophages irrespective of the phage family, preventing entry into the cell. In contrast, resistance was intracellular in practically all interactions against generalist T4-like cyanophages. The stage of intracellular arrest was interaction-specific, halting at various stages of the infection cycle. Incomplete infection cycles proceeded to various degrees of phage genome transcription and translation as well as phage genome replication in numerous interactions. In a particularly intriguing case, intracellular capsid assembly was observed, but the phage genome was not packaged. The cyanobacteria survived the encounter despite late-stage infection and partial genome degradation. We hypothesize that this is tolerated due to genome polyploidy, which we found for certain strains of both Synechococcus and Prochlorococcus Our findings unveil a heavy cost of promiscuous entry of generalist phages into nonhost cells that is rarely paid by specialist phages and suggests the presence of unknown mechanisms of intracellular resistance in the marine unicellular cyanobacteria. Furthermore, these findings indicate that the range for virus-mediated horizontal gene transfer extends beyond hosts to nonhost cyanobacterial cells., Competing Interests: The authors declare no conflict of interest., (Copyright © 2019 the Author(s). Published by PNAS.)

Cyanophages of the Myoviridae family include generalist viruses capable of infecting a wide range of hosts including those from different cyanobacterial genera. While the influence of phages on host evolution has been studied previously, it is not known how the infection of distinct hosts influences the evolution of cyanophage populations. Here, using an experimental evolution approach, we investigated the adaptation of multiple cyanophage populations to distinct cyanobacterial hosts. We show that when infecting an "optimal" host, whose infection is the most efficient, phage populations accumulated only a few mutations. However, when infecting "sub-optimal" hosts, different mutations spread in the phage populations, leading to rapid diversification into distinct subpopulations. Based on our results, we propose a model demonstrating how shifts in microbial abundance, which lead to infection of "sub-optimal" hosts, act as a driver for rapid diversification of viral populations.

Introduction: In Nepal, cervical cancer is the most common female cancer. Unfortunately, there is no uniform effective screening system available all around the country. The objective of this study is to evaluate the cytology, Visual Inspection with Acetic Acid and with Lugol's Iodine alone or in combination to detect a pre-cancerous lesion in rural Nepal., Methods: It is an analytical cross-sectional study. Convenience sampling technique was used to select participants who were apparently healthy, married, non- pregnant women of aged 20-65 years for cervical cancer screening program. Screening tests were performed on all eligible women (n=2143) after socio-demographic and reproductive health data collection. A biopsy was applied as a gold standard test. Cross-tabulations were used to describe the test sensitivity, specificity, positive predictive value, and negative predictive value at a 95% confidence interval. Diagnostic odds ratio was also calculated., Results: A majority, 2143 (94%), of women accepted and participated in this study. The sensitivity vs specificity of cytology, VIA, and VILI was 57.1% vs 98.3%, 71.4% vs 88.8% and 78.6% vs 85.1%, and of the co-testing of 'Both positive VIA and VILI' and 'Either positive VIA or VILI' was 64.3% vs 85.7% and 90.1% vs 83.7% respectively. Negative predictive value of all tests exceeded 99.7%. Cytology had the highest Diagnostic odds ratio (64.9), followed by the co-test 'Either positive VIA or VILI' (27.7)., Conclusions: Cervical cancer screening by co-testing 'Either positive VIA or VILI' is more useful than cytology; VIA and or VILI are easy, safe, feasible and well-accepted tests in a low resource setting, Nepal.

Prochlorococcus and Synechococcus are the dominant primary producers in marine ecosystems and perform a significant fraction of ocean carbon fixation. These cyanobacteria interact with a diverse microbial community that coexists with them. Comparative genomics of cultivated isolates has helped address questions regarding patterns of evolution and diversity among microbes, but the fraction that can be cultivated is miniscule compared to the diversity in the wild. To further probe the diversity of these groups and extend the utility of reference sequence databases, we report a data set of single cell genomes for 489 Prochlorococcus, 50 Synechococcus, 9 extracellular virus particles, and 190 additional microorganisms from a diverse range of bacterial, archaeal, and viral groups. Many of these uncultivated single cell genomes are derived from samples obtained on GEOTRACES cruises and at well-studied oceanographic stations, each with extensive suites of physical, chemical, and biological measurements. The genomic data reported here greatly increases the number of available Prochlorococcus genomes and will facilitate studies on evolutionary biology, microbial ecology, and biological oceanography.

Objective: To assess the burden of cervical neoplasia in mid-western rural, Nepal using cytology, visual inspection with acetic acid (VIA) and visual inspection with Lugol's iodine (VILI)., Method: A cross-sectional, population-based study was conducted. Total of 2,279 married, non-pregnant women aged 20-65 years participated in a screening clinic from May 2016 to January 2017. All eligible women completed self-report of socio-demographic and reproductive health data followed by screening tests. Biopsies were obtained from areas on the cervix assessed by VIA and or VILI to be abnormal. Final disease was confirmed by biopsy report., Results: A total of 96.09% (n=2,190) women were eligible for this study with mean age 32.78±9.33 years. The overall rate of positive cytology, VIA, and VILI were 3.69%, 12.45%, and 16.89%, respectively. Sixty-two cases were biopsy proven cervical neoplasia. Altogether 78 (3.69%) cases were cytologically abnormal: 25 (1.18%) were atypical squamous cells of undetermined significance, 33 (1.56%) were low-grade squamous intraepithelial lesion, 11 (0.52%) were high-grade squamous intraepithelial lesion, and 9 (0.42%) were squamous cell carcinoma. Illiterate women appeared to be at higher risk for cervical neoplasia (p<0.001). Similarly, age ≥46 years (p<0.013), participant's multiple marriages or sexual partners (p<0.005), and positive human immunodeficiency virus status (p<0.001) were significantly associated with abnormal cytology., Conclusion: Based on cytology report, there is 3.69% prevalence of cervical neoplasia among women in a rural region of mid-western, Nepal. A "screen and treat" approach would be more attractive in low resource settings., Competing Interests: No potential conflict of interest relevant to this study was reported., (Copyright © 2018. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology.)

Through clinical immersion experiences (IEs), prelicensure nursing students work with a registered nurse preceptor to experience their schedule and patient assignment. IEs can have advantages for the practice and academic partners and individual students. However, there are also challenges to providing IEs, particularly for healthcare organizations. Collaborative planning and results are reported of a promising IE model, the hybrid immersion experience, which addressed the disadvantages and resulted in positive outcomes for all stakeholders.

Viruses are globally abundant and extremely diverse in their genetic make-up and in the hosts they infect. Although they influence the abundance, diversity and evolution of their hosts, current methods are inadequate for gaining a quantitative understanding of their impact on these processes. Here we report the adaptation of the solid-phase single-molecule PCR polony method for the quantification of taxonomically relevant groups of diverse viruses. Using T7-like cyanophages as our model, we found the polony method to be far superior to regular quantitative PCR methods and droplet digital PCR when degenerate primers were used to encompass the group's diversity. This method revealed that T7-like cyanophages were highly abundant in the Red Sea in spring 2013, reaching 770,000 phages ml -1 , and displaying a similar depth distribution pattern to cyanobacteria. Furthermore, the abundances of two major clades within the T7-like cyanophages differed dramatically throughout the water column: clade B phages that carry the psbA photosynthesis gene and infect either Synechococcus or Prochlorococcus were at least 20-fold more abundant than clade A phages that lack psbA and infect Synechococcus hosts. Such measurements are of paramount importance for understanding virus population dynamics and the impact of viruses on different microbial taxa and for modelling viral influence on ecosystem functioning on a global scale.

Cyanobacteria are important contributors to primary production in the open oceans. Over the past decade, various photosynthesis-related genes have been found in viruses that infect cyanobacteria (cyanophages). Although photosystem II (PSII) genes are common in both cultured cyanophages and environmental samples 1-4 , viral photosystem I (vPSI) genes have so far only been detected in environmental samples 5,6 . Here, we have used a targeted strategy to isolate a cyanophage from the tropical Pacific Ocean that carries a PSI gene cassette with seven distinct PSI genes (psaJF, C, A, B, K, E, D) as well as two PSII genes (psbA, D). This cyanophage, P-TIM68, belongs to the T4-like myoviruses, has a prolate capsid, a long contractile tail and infects Prochlorococcus sp. strain MIT9515. Phage photosynthesis genes from both photosystems are expressed during infection, and the resultant proteins are incorporated into membranes of the infected host. Moreover, photosynthetic capacity in the cell is maintained throughout the infection cycle with enhancement of cyclic electron flow around PSI. Analysis of metagenomic data from the Tara Oceans expedition 7 shows that phages carrying PSI gene cassettes are abundant in the tropical Pacific Ocean, composing up to 28% of T4-like cyanomyophages. They are also present in the tropical Indian and Atlantic Oceans. P-TIM68 populations, specifically, compose on average 22% of the PSI-gene-cassette carrying phages. Our results suggest that cyanophages carrying PSI and PSII genes are likely to maintain and even manipulate photosynthesis during infection of their Prochlorococcus hosts in the tropical oceans.

Phages and hosts coexist in nature with a high degree of population diversity. This is often explained through coevolutionary models, such as the arms race or density-dependent fluctuating selection, which differ in assumptions regarding the emergence of phage mutants that overcome host resistance. Previously, resistance in the abundant marine cyanobacterium, Prochlorococcus, was found to occur frequently. However, little is known about the ability of phages to overcome this resistance. Here we report that, in some cases, T7-like cyanophage mutants emerge to infect resistant Prochlorococcus strains. These resistance-breaking phages retained the ability to infect the wild-type host. However, fitness of the mutant phages differed on the two hosts. Furthermore, in one case, resistance-breaking was accompanied by costs of decreased fitness on the wild-type host and decreased adsorption specificity, relative to the wild-type phage. In two other cases, fitness on the wild-type host increased. Whole-genome sequencing revealed mutations in probable tail-related genes. These were highly diverse in isolates and natural populations of T7-like cyanophages, suggesting that antagonistic coevolution enhances phage genome diversity. Intriguingly, most interactions did not yield resistance-breaking phages. Thus, resistance mutations raise genetic barriers to continuous arms race cycles and are indicative of an inherent asymmetry in coevolutionary capacity, with hosts having the advantage. Nevertheless, phages coexist with hosts, which we propose relies on combined, parallel action of a limited arms race, fluctuating selection and passive host-switching within diverse communities. Together, these processes generate a constantly changing network of interactions, enabling stable coexistence between hosts and phages in nature.

Synechococcus is an abundant marine cyanobacterium that significantly contributes to primary production. Lytic phages are thought to have a major impact on cyanobacterial population dynamics and evolution. Previously, an investigation of the transcriptional response of three Synechococcus strains to infection by the T4-like cyanomyovirus, Syn9, revealed that while the transcript levels of the vast majority of host genes declined soon after infection, those for some genes increased or remained stable. In order to assess the role of two such host-response genes during infection, we inactivated them in Synechococcus sp. strain WH8102. One gene, SYNW1659, encodes a domain of unknown function (DUF3387) that is associated with restriction enzymes. The second gene, SYNW1946, encodes a PIN-PhoH protein, of which the PIN domain is common in bacterial toxin-antitoxin systems. Neither of the inactivation mutations impacted host growth or the length of the Syn9 lytic cycle. However, the DUF3387 mutant supported significantly lower phage DNA replication and yield of phage progeny than the wild-type, suggesting that the product of this host gene aids phage production. The PIN-PhoH mutant, on the other hand, allowed for significantly higher Syn9 genomic DNA replication and progeny production, suggesting that this host gene plays a role in restraining the infection process. Our findings indicate that host-response genes play a functional role during infection and suggest that some function in an attempt at defense against the phage, while others are exploited by the phage for improved infection.

In China, nurses have limited presence in schools, thus, adolescent girls often lack accurate information about menstrual health, which may lead to incorrect and unhealthy menstrual-related behavior. This study investigated the effects of a culturally and developmentally tailored nursing intervention on the menstrual health of adolescent girls in China. Following institutional review board approval, adolescent girls aged 12-15 were recruited from two schools. A quasi-experimental, pretest-posttest design examined the effects of five interactive education sessions on menstrual health. The final sample included 116 adolescent girls. Significant improvement was observed in the intervention group regarding menstrual knowledge, confidence in performing menstrual healthcare behavior, and dysmenorrhea related self-care behavior. A nurse-managed education program improved adolescent girls' menstrual knowledge, promoted a more positive attitude, encouraged confidence, and improved pain relief practice. We recommend that professional nurses globally advocate for school nursing and routine menstrual health education for adolescent girls., (© 2016 John Wiley & Sons Australia, Ltd.)

Little information regarding viral progeny production (burst size) and host mortality (viral virulence) is currently available for environmentally relevant phages. This is partially due to the difficulty in accurately measuring these infection properties with existing methods. Here, we set up a simple system for determining viral virulence and burst size at the single-cell level following flow cytometric separation of infected cells. We applied this assay to two distinct cyanomyoviruses, Syn9 and S-TIM5, during infection of two marine Synechococcus strains each. We found that virulence ranged from 44%-82%, differing for the same phage on different hosts. Average burst sizes ranged from 21-43 infective viruses/cell, and differed with host for Syn9, whereas the burst size of S-TIM5 was similar for both hosts. In addition, virulence and burst sizes were different for the two phages when infecting their common host. Furthermore, wide-ranging cell-to-cell variability was found for single-cell burst sizes in each of the four interactions, ranging from 2 to over 100 infective viruses/cell. This variability, discerned at both the population and single-cell levels under controlled laboratory conditions, is likely to be much more complex in natural environments., (© 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.)

This study examined the supports, barriers, and strategies to successful progression in a DNP program using a nationwide online survey of DNP students and graduates. Subjects (n = 172) had a mean age of 46.2 years; 83% worked full time. Major barriers were competing demands of work, family, and school. Perseverance was a key element in overcoming barriers; most students reported being overwhelmed, and 37% considered quitting. Mechanisms for programs to consider in addressing this stress are discussed.

Previous studies have shown that infection of Prochlorococcus MED4 by the cyanophage P-SSP7 leads to increased transcript levels of host endoribonuclease (RNase) E. However, it has remained enigmatic whether this is part of a host defense mechanism to degrade phage messenger RNA (mRNA) or whether this single-strand RNA-specific RNase is utilized by the phage. Here we describe a hitherto unknown means through which this cyanophage increases expression of RNase E during phage infection and concomitantly protects its own RNA from degradation. We identified two functionally different RNase E mRNA variants, one of which is significantly induced during phage infection. This transcript lacks the 5' UTR, is considerably more stable than the other transcript, and is likely responsible for increased RNase E protein levels during infection. Furthermore, selective enrichment and in vivo analysis of double-stranded RNA (dsRNA) during infection revealed that phage antisense RNAs (asRNAs) sequester complementary mRNAs to form dsRNAs, such that the phage protein-coding transcriptome is nearly completely covered by asRNAs. In contrast, the host protein-coding transcriptome is only partially covered by asRNAs. These data suggest that P-SSP7 orchestrates degradation of host RNA by increasing RNase E expression while masking its own transcriptome from RNase E degradation in dsRNA complexes. We propose that this combination of strategies contributes significantly to phage progeny production., (Copyright © 2016 by the Genetics Society of America.)

Cyanobacteria are highly abundant in the oceans and are constantly exposed to lytic viruses. The T4-like cyanomyoviruses are abundant in the marine environment and have broad host-ranges relative to other cyanophages. It is currently unknown whether broad host-range phages specifically tailor their infection program for each host, or employ the same program irrespective of the host infected. Also unknown is how different hosts respond to infection by the same phage. Here we used microarray and RNA-seq analyses to investigate the interaction between the Syn9 T4-like cyanophage and three phylogenetically, ecologically and genomically distinct marine Synechococcus strains: WH7803, WH8102 and WH8109. Strikingly, Syn9 led a nearly identical infection and transcriptional program in all three hosts. Different to previous assumptions for T4-like cyanophages, three temporally regulated gene expression classes were observed. Furthermore, a novel regulatory element controlled early-gene transcription, and host-like promoters drove middle gene transcription, different to the regulatory paradigm for T4. Similar results were found for the P-TIM40 phage during infection of Prochlorococcus NATL2A. Moreover, genomic and metagenomic analyses indicate that these regulatory elements are abundant and conserved among T4-like cyanophages. In contrast to the near-identical transcriptional program employed by Syn9, host responses to infection involved host-specific genes primarily located in hypervariable genomic islands, substantiating islands as a major axis of phage-cyanobacteria interactions. Our findings suggest that the ability of broad host-range phages to infect multiple hosts is more likely dependent on the effectiveness of host defense strategies than on differential tailoring of the infection process by the phage.

Context: Critical thinking (CT) is a fundamental skill for clinicians. It plays an essential role in clinical decision making, which has implications for diagnostic accuracy, appropriate management and, ultimately, patient outcomes. Many theoretical frameworks have conceptualised CT and its related constructs. Nevertheless, it is unclear how this topic is taught by faculty staff who teach health professionals., Methods: The purpose of this multi-site qualitative study was to characterise the instructional strategies of faculty members actively teaching CT. We used semi-structured interviews to answer the following questions: (i) What approaches do faculty staff recognised by peers as good teachers in CT use to teach CT? (ii) How explicit is this teaching? We used snowball recruitment at eight participating institutions to identify faculty staff considered to be local experts in teaching CT. Forty-four eligible faculty members agreed to participate in semi-structured interviews, which were recorded and transcribed. We used the framework method to analyse the qualitative data., Results: We organised the findings into themes of what faulty staff teach to learners (habits of mind, such as higher-order thinking and metacognition), how they teach (guiding principles of clinical relevance and perspective shifting, and concrete strategies such as questioning and group interaction) and why they teach CT (to produce the best possible health outcomes for patients)., Conclusion: This work has practical recommendations for the individual faculty member. Promoting higher-level cognition, asking questions that probe the learner's understanding and linking discussions to the clinical context are some of the approaches that can be incorporated immediately., (© 2016 John Wiley & Sons Ltd.)