Temporal variability in the relationship between line height absorption and chlorophyll concentration: a case study from the Northern Gulf of Alaska.

The Line Height Absorption (LHA) method uses absorption of light to estimate chlorophyll-a. While most users consider regional variability and apply corrections, the effect of temporal variability is typically not explored. The Northern Gulf of Alaska (NGA) was selected for this study because there was no published regional value and its large swings in temporal productivity would make it a good candidate to evaluate the effect of temporal variability on the relationship. The mean NGA value of 0.0114 obtained here should be treated with caution, as variation in the slope of the relationship (aLH*), and thus chlorophyll-a estimates, in the NGA region varied by ∼25% between spring (aLH* = 0.0109) and summer (aLH* = 0.0137). Results suggest that this change is driven by a shift in pigment packaging and cell size associated with changes in mixed layer depth and stratification. Consideration of how temporal variability may affect the accuracy of the LHA method in other regions is thus recommended.

Ecosystem response persists after a prolonged marine heatwave.

Some of the longest and most comprehensive marine ecosystem monitoring programs were established in the Gulf of Alaska following the environmental disaster of the Exxon Valdez oil spill over 30 years ago. These monitoring programs have been successful in assessing recovery from oil spill impacts, and their continuation decades later has now provided an unparalleled assessment of ecosystem responses to another newly emerging global threat, marine heatwaves. The 2014-2016 northeast Pacific marine heatwave (PMH) in the Gulf of Alaska was the longest lasting heatwave globally over the past decade, with some cooling, but also continued warm conditions through 2019. Our analysis of 187 time series from primary production to commercial fisheries and nearshore intertidal to offshore oceanic domains demonstrate abrupt changes across trophic levels, with many responses persisting up to at least 5 years after the onset of the heatwave. Furthermore, our suite of metrics showed novel community-level groupings relative to at least a decade prior to the heatwave. Given anticipated increases in marine heatwaves under current climate projections, it remains uncertain when or if the Gulf of Alaska ecosystem will return to a pre-PMH state.

Humanistic medicine in anaesthesiology: development and assessment of a curriculum in humanism for postgraduate anaesthesiology trainees.

BACKGROUND: An unintended consequence of medical technologies is loss of personal interactions and humanism between patients and their healthcare providers, leading to depersonalisation of medicine. As humanism is not integrated as part of formal postgraduate anaesthesiology education curricula, our goal was to design, introduce, and evaluate a comprehensive humanism curriculum into anaesthesiology training. METHODS: Subject-matter experts developed and delivered the humanism curriculum, which included interactive workshops, simulation sessions, formal feedback, and patient immersion experience. The effectiveness of the programme was evaluated using pre- and post-curriculum assessments in first-year postgraduate trainee doctors (residents). RESULTS: The anaesthesiology residents reported high satisfaction scores. Pre-/post-Jefferson Scale of Patient Perceptions of Physician Empathy showed an increase in empathy ratings with a median improvement of 12 points (range; P=0.013). After training, patients rated the residents as more empathetic (31 [4] vs 22 [5]; P<0.001; 95% confidence interval [CI]: 7-12) and professional (47 [3] vs 35 [8]; P<0.001; 95% CI: 9-16). Patient overall satisfaction with their anaesthesia provider improved after training (51 [6] vs 37 [10]; P<0.001; 95% CI: 10-18). Patients rated their anxiety lower in the post-training period compared with pretraining (1.8 [2.3] vs 3.6 [1.6]; P=0.001; 95% CI: 0.8-2.9). Patient-reported pain scores decreased after training (2.3 [2.5] vs 3.8 [2.1]; P=0.010; 95% CI: 0.4-2.8). CONCLUSIONS: Implementation of a humanism curriculum during postgraduate anaesthesiology training was well accepted, and can result in increased physician empathy and professionalism. This may improve patient pain, anxiety, and overall satisfaction with perioperative care.

Contrasting effects of high-intensity photosynthetically active radiation on two bloom-forming dinoflagellates.

While light limitation can inhibit bloom formation in dinoflagellates, the potential for high-intensity photosynthetically active radiation (PAR) to inhibit blooms by causing stress or damage has not been well-studied. We measured the effects of high-intensity PAR on the bloom-forming dinoflagellates Alexandrium fundyense and Heterocapsa rotundata. Various physiological parameters (photosynthetic efficiency Fv /Fm , cell permeability, dimethylsulfoniopropionate [DMSP], cell volume, and chlorophyll-a content) were measured before and after exposure to high-intensity natural sunlight in short-term light stress experiments. In addition, photosynthesis-irradiance (P-E) responses were compared for cells grown at different light levels to assess the capacity for photophysiological acclimation in each species. Experiments revealed distinct species-specific responses to high PAR. While high light decreased Fv /Fm in both species, A. fundyense showed little additional evidence of light stress in short-term experiments, although increased membrane permeability and intracellular DMSP indicated a response to handling. P-E responses further indicated a high light-adapted species with Chl-a inversely proportional to growth irradiance and no evidence of photoinhibition; reduced maximum per-cell photosynthesis rates suggest a trade-off between photoprotection and C fixation in high light-acclimated cells. Heterocapsa rotundata cells, in contrast, swelled in response to high light and sometimes lysed in short-term experiments, releasing DMSP. P-E responses confirmed a low light-adapted species with high photosynthetic efficiencies associated with trade-offs in the form of substantial photoinhibition and a lack of plasticity in Chl-a content. These contrasting responses illustrate that high light constrains dinoflagellate community composition through species-specific stress effects, with consequences for bloom formation and ecological interactions within the plankton.

Comparing the Results of Written Testing for Advanced Cardiac Life Support Teaching Using Team-based Learning and the "Flipped Classroom" Strategy.

Objectives We sought to further determine whether cognitive test results changed for advanced cardiac life support (ACLS) taught in the team-based learning/flipped classroom format (TBL/FC) versus a lecture-based (LB) control. Methods We delivered 2010 ACLS to two classes of fourth-year medical students in the TBL/FC format (2015-2016), compared to three classes in the LB format (2012-2014). There were 27.5 hours of instruction for the TBL/FC model (TBL - 10.5 hours, podcasts - nine hours, small-group simulation - eight hours), and 20 hours (lectures - 12 hours, simulation - eight hours) in LB. We taught TBL for 13 cardiac cases while LB had none. Didactic content and seven simulated cases were the same in lecture (2012-2014) or in podcast formats (2015-2016). Testing was the same using 50 multiple-choice (MC) format questions, 20 rhythm-matching questions, and seven fill-in management of simulated cases. Results Some 468 students enrolled in the course 259 (55.4%) in the LB format in 2012-2014, and 209 (44.6%) in the TBL/FC format in 2015-2016. The scores for two out of three tests (MC and fill-in) increased with TBL/FC. Combined, median scores increased from 93.5% (IQR 90.6, 95.4) to 95.1% (92.5, 96.8, p = 0.0001). More students did not pass one of three tests with LB versus TBL/FC (24.7% versus 18.2%), and two or three parts of the test (8.1% versus 4.3%, p = 0.01). On the contrary, 77.5% passed all three with TBL/FC versus 67.2% with LB (change 10.3%, 95% CI 2.2%-18.2%). Conclusion TBL/FC teaching for ACLS improved written test results compared with the LB format.

Major transitions in dinoflagellate evolution unveiled by phylotranscriptomics.

Dinoflagellates are key species in marine environments, but they remain poorly understood in part because of their large, complex genomes, unique molecular biology, and unresolved in-group relationships. We created a taxonomically representative dataset of dinoflagellate transcriptomes and used this to infer a strongly supported phylogeny to map major morphological and molecular transitions in dinoflagellate evolution. Our results show an early-branching position of Noctiluca, monophyly of thecate (plate-bearing) dinoflagellates, and paraphyly of athecate ones. This represents unambiguous phylogenetic evidence for a single origin of the group's cellulosic theca, which we show coincided with a radiation of cellulases implicated in cell division. By integrating dinoflagellate molecular, fossil, and biogeochemical evidence, we propose a revised model for the evolution of thecal tabulations and suggest that the late acquisition of dinosterol in the group is inconsistent with dinoflagellates being the source of this biomarker in pre-Mesozoic strata. Three distantly related, fundamentally nonphotosynthetic dinoflagellates, Noctiluca, Oxyrrhis, and Dinophysis, contain cryptic plastidial metabolisms and lack alternative cytosolic pathways, suggesting that all free-living dinoflagellates are metabolically dependent on plastids. This finding led us to propose general mechanisms of dependency on plastid organelles in eukaryotes that have lost photosynthesis; it also suggests that the evolutionary origin of bioluminescence in nonphotosynthetic dinoflagellates may be linked to plastidic tetrapyrrole biosynthesis. Finally, we use our phylogenetic framework to show that dinoflagellate nuclei have recruited DNA-binding proteins in three distinct evolutionary waves, which included two independent acquisitions of bacterial histone-like proteins.

Flipping the Advanced Cardiac Life Support Classroom with Team-based Learning: Comparison of Cognitive Testing Performance for Medical Students at the University of California, Irvine, United States.

PURPOSE: It aimed to find if written test results improved for advanced cardiac life support (ACLS) taught in flipped classroom/team-based Learning (FC/TBL) vs. lecture-based (LB) control in University of California-Irvine School of Medicine, USA. METHODS: Medical students took 2010 ACLS with FC/TBL (2015), compared to 3 classes in LB (2012-14) format. There were 27.5 hours of instruction for FC/TBL model (TBL 10.5, podcasts 9, small-group simulation 8 hours), and 20 (12 lecture, simulation 8 hours) in LB. TBL covered 13 cardiac cases; LB had none. Seven simulation cases and didactic content were the same by lecture (2012-14) or podcast (2015) as was testing: 50 multiple-choice questions (MCQ), 20 rhythm matchings, and 7 fill-in clinical cases. RESULTS: 354 students took the course (259 [73.1%] in LB in 2012-14, and 95 [26.9%] in FC/TBL in 2015). Two of 3 tests (MCQ and fill-in) improved for FC/TBL. Overall, median scores increased from 93.5% (IQR 90.6, 95.4) to 95.1% (92.8, 96.7, P=0.0001). For the fill-in test: 94.1% for LB (89.6, 97.2) to 96.6% for FC/TBL (92.4, 99.20 P=0.0001). For MC: 88% for LB (84, 92) to 90% for FC/TBL (86, 94, P=0.0002). For the rhythm test: median 100% for both formats. More students failed 1 of 3 tests with LB vs. FC/TBL (24.7% vs. 14.7%), and 2 or 3 components (8.1% vs. 3.2%, P=0.006). Conversely, 82.1% passed all 3 with FC/TBL vs. 67.2% with LB (difference 14.9%, 95% CI 4.8-24.0%). CONCLUSION: A FC/TBL format for ACLS marginally improved written test results.

Correlation of Simulation Examination to Written Test Scores for Advanced Cardiac Life Support Testing: Prospective Cohort Study.

INTRODUCTION: Traditional Advanced Cardiac Life Support (ACLS) courses are evaluated using written multiple-choice tests. High-fidelity simulation is a widely used adjunct to didactic content, and has been used in many specialties as a training resource as well as an evaluative tool. There are no data to our knowledge that compare simulation examination scores with written test scores for ACLS courses. OBJECTIVE: To compare and correlate a novel high-fidelity simulation-based evaluation with traditional written testing for senior medical students in an ACLS course. METHODS: We performed a prospective cohort study to determine the correlation between simulation-based evaluation and traditional written testing in a medical school simulation center. Students were tested on a standard acute coronary syndrome/ventricular fibrillation cardiac arrest scenario. Our primary outcome measure was correlation of exam results for 19 volunteer fourth-year medical students after a 32-hour ACLS-based Resuscitation Boot Camp course. Our secondary outcome was comparison of simulation-based vs. written outcome scores. RESULTS: The composite average score on the written evaluation was substantially higher (93.6%) than the simulation performance score (81.3%, absolute difference 12.3%, 95% CI [10.6-14.0%], p<0.00005). We found a statistically significant moderate correlation between simulation scenario test performance and traditional written testing (Pearson r=0.48, p=0.04), validating the new evaluation method. CONCLUSION: Simulation-based ACLS evaluation methods correlate with traditional written testing and demonstrate resuscitation knowledge and skills. Simulation may be a more discriminating and challenging testing method, as students scored higher on written evaluation methods compared to simulation.

Impact assessment of perioperative point-of-care ultrasound training on anesthesiology residents.

BACKGROUND: The perioperative surgical home model highlights the need for trainees to include modalities that are focused on the entire perioperative experience. The focus of this study was to design, introduce, and evaluate the integration of a whole-body point-of-care (POC) ultrasound curriculum (Focused periOperative Risk Evaluation Sonography Involving Gastroabdominal Hemodynamic and Transthoracic ultrasound) into residency training. METHODS: For 2 yr, anesthesiology residents (n = 42) received lectures using a model/simulation design and half were also randomly assigned to receive pathology assessment training. Posttraining performance was assessed through Kirkpatrick levels 1 to 4 outcomes based on the resident satisfaction surveys, multiple-choice tests, pathologic image evaluation, human model testing, and assessment of clinical impact via review of clinical examination data. RESULTS: Evaluation of the curriculum demonstrated high satisfaction scores (n = 30), improved content test scores (n = 37) for all tested categories (48 ± 16 to 69 ± 17%, P < 0.002), and improvement on human model examinations. Residents randomized to receive pathology training (n = 18) also showed higher scores compared with those who did not (n = 19) (9.1 ± 2.5 vs. 17.4 ± 3.1, P < 0.05). Clinical examinations performed in the organization after the study (n = 224) showed that POC ultrasound affected clinical management at a rate of 76% and detected new pathology at a rate of 31%. CONCLUSIONS: Results suggest that a whole-body POC ultrasound curriculum can be effectively taught to anesthesiology residents and that this training may provide clinical benefit. These results should be evaluated within the context of the perioperative surgical home.

Connecting alveolate cell biology with trophic ecology in the marine plankton using the ciliate Favella as a model.

Planktonic alveolates (ciliates and dinoflagellates), key trophic links in marine planktonic communities, exhibit complex behaviors that are underappreciated by microbiologists and ecologists. Furthermore, the physiological mechanisms underlying these behaviors are still poorly understood except in a few freshwater model ciliates, which are significantly different in cell structure and behavior than marine planktonic species. Here, we argue for an interdisciplinary research approach to connect physiological mechanisms with population-level outcomes of behaviors. Presenting the tintinnid ciliate Favella as a model alveolate, we review its population ecology, behavior, and cellular/molecular biology in the context of sensory biology and synthesize past research and current findings to construct a conceptual model describing the sensory biology of Favella. We discuss how emerging genomic information and new technical methods for integrating research across different levels of biological organization are paving the way for rapid advance. These research approaches will yield a deeper understanding of the role that planktonic alveolates may play in biogeochemical cycles, and how they may respond to future ocean conditions.

High-fidelity simulation enhances ACLS training.

BACKGROUND: Medical student training and experience in cardiac arrest situations is limited. Traditional Advanced Cardiac Life Support (ACLS) teaching methods are largely unrealistic with rare personal experience as team leader. Yet Postgraduate Year 1 residents may perform this role shortly after graduation. PURPOSES: We expanded our ACLS teaching to a "Resuscitation Boot Camp" where we taught 2010 ACLS to 19 pregraduation students in didactic (12 hours) and experiential (8 hours) format. METHODS: Immediately before the course, we recorded students performing an acute coronary syndrome/ventricular fibrillation (VF) scenario. As a final test, we recorded the same scenario for each student. Primary outcomes were time to cardiopulmonary resuscitation (CPR) and defibrillation (DF). Secondary measures were total scenario score, dangerous actions, proportion of students voicing "ventricular fibrillation," 12-lead ST-elevation myocardial infarction (STEMI) interpretation, and care necessary for return of spontaneous circulation (ROSC). Two expert ACLS instructors scored both performances on a 121-point scale, with each student serving as their own control. We used t tests and McNemar tests for paired data with statistical significance at p<.05. RESULTS: Before instruction, average time from arrest to CPR was 112 seconds and to first DF 3.01 minutes. Students scored 45±9/121 points and 9/19 (49%) performed dangerous actions. After instruction, time to CPR was 12 seconds (p=004) and to first DF 1.53 minutes (p=.03). Time to DF was delayed as students showed mastery of bag-valve-mask ventilation before DF. After instruction, students scored 97±4/121 points (p<.0001) with no dangerous actions. Before training, only 4 of 19 (21%) students performed both CPR and DF within 2 minutes, and 3 of these had ROSC. After training, 14 of 19 (74%) achieved CPR+DF≤2 minutes (p=.002), and all had ROSC. Before training, 5 of 19 (26%) students said "VF" and 4 of 19 obtained an ECG, but none identified STEMI. After training, corresponding performance was 13 of 19 "VF" (68%, p=021) and 100% ECG and STEMI identification (p<.05). CONCLUSIONS: This course significantly improved knowledge and psychomotor skills. Critical actions required for resuscitation were much more common after training. ACLS training including high-fidelity simulation decreases time to CPR and DF and improves performance during resuscitation.

Transitioning from 1:1 to 1: 2 Supervision in Anesthesia Training: A Descriptive Survey.

BACKGROUND: Advancement from 1:1 to 1:2 (attending to resident) supervision at the beginning of a CA-1 (clinical anesthesia) year can serve as a model for transition to milestone-based curricula. Currently most programs have an individual mixture of training and advancement criteria formed at the discretion of educational leadership. We designed a questionnaire to evaluate degree of variability at programs nationally. METHODS: After obtaining IRB approval, an anonymous survey was sent via Survey Monkey to all Anesthesiology Residency Program Directors with a link for faculty members. The survey remained open for 30 days and two reminders for completion were sent. RESULTS: Among responses from Program Directors, the following competency areas showed most agreement in being absolutely required for advancement: when to call an attending (78%), preoxygenation (60%), room preparation (81%), monitor placement (81%), machine check (77%), and airway assessment (73%). Responses from faculty identified as most important when to call the attending (82%), basic crisis management while waiting for help (64%), monitor placement (77%), machine check (79%), room preparation(77%), and airway assessment (66%). CONCLUSIONS: There are no clear guidelines for transition from 1:1 to 1:2 supervision with wide variability in the design and requirements for the transition. With only modest agreement among and between Residency Program Directors and faculty members at this clearly defined transition, the challenges of implementation of milestones at every level are significant.

Illness uncertainty and quality of life in children with cancer.

BACKGROUND: Illness uncertainty is prevalent in children with cancer and has been associated with increased psychological distress. The relationship between illness uncertainty and quality of life in pediatric cancer patients remains unclear. The aim of the present study was to examine illness uncertainty as a predictor of health-related quality of life in children diagnosed with cancer. It was hypothesized that child-reported illness uncertainty would be negatively associated with child health-related quality of life. PROCEDURE: Children aged 8 to 18 years old and receiving treatment for cancer were recruited to participate in this study. One hundred twenty children and their parent(s) completed measures of illness uncertainty, pain, anxiety, and quality of life during a routine visit to the Cancer Center at Children's Hospital of Orange County. RESULTS: Illness uncertainty was significantly associated with child age (P=0.02), overall health-related (P<0.001) and cancer-related (P<0.001) quality of life, but not with treatment status (on/off chemotherapy) or demographic variables including sex and household income. Regression analyses statistically controlling for age, anxiety, and pain revealed that illness uncertainty significantly predicted child-reported cancer-related and health-related quality of life (P<0.01) as well as parent-reported cancer-specific quality of life (P<0.01). CONCLUSIONS: Illness uncertainty is prevalent and associated with lower quality of life in children diagnosed with cancer. Improved communication with children regarding disease state, treatment expectations, and prognosis may alleviate uncertainty and improve functioning in this vulnerable patient population.

Ethnicity and parental report of postoperative behavioral changes in children.

OBJECTIVES: To examine the role of ethnicity and language in parent report of children's postoperative behavioral recovery. AIM: To compare incidence of new onset negative behavior change in English- and Spanish-speaking White and Hispanic children following outpatient surgery. BACKGROUND: Postoperative behavioral change in children is common; however, it is unknown whether cultural variables including ethnicity and language may influence parent report of children's behavioral recovery. METHODS/MATERIALS: Participants included 288 parents (English-speaking White, English-speaking Hispanic, Spanish-speaking Hispanic parents) of children undergoing outpatient elective surgery. Parents completed the post-hospitalization behavior questionnaire (PHBQ) and parents' postoperative pain measure (PPPM) on postoperative days one, three, and seven at home. RESULTS: Most parents (83%) reported onset of new negative behavioral change in children postoperatively. Generalized estimating equations revealed significant group differences in overall behavior change [Wald χ(2)(12) = 375.69, P < 0.0001] after controlling for demographic and socioeconomic differences. At all three postoperative days, Spanish-speaking Hispanic (SSH) parents reported lower negative behavioral changes in their children compared to English-speaking White (ESW) parents (day 1: P < 0.01; day 3: P < 0.001; day 7: P < 0.10). On postoperative days one and three, SSH parents also reported lower total PHBQ scores than English-speaking Hispanic (ESH) parents [day 1: χ(2)(1) = 6.72, P = 0.01; day 3: χ(2)(1) = 7.98, P = 0.005]. CONCLUSION: The present study provides evidence that parent report of children's postoperative behavioral recovery may be influenced by cultural variables, such as ethnicity and language. The present results contribute to a growing body of evidence that highlights the need for culturally sensitive assessment and care of families in the medical setting. The findings may reflect differences in cultural values such as stoicism; however, future studies would benefit from examination of the factors that may account for the differences in reported behavior change after surgery (i.e., report bias, cultural values).

Broad Salinity Tolerance as a Refuge from Predation in the Harmful Raphidophyte Alga Heterosigma akashiwo (Raphidophyceae).

The ability of harmful algal species to form dense, nearly monospecific blooms remains an ecological and evolutionary puzzle. We hypothesized that predation interacts with estuarine salinity gradients to promote blooms of Heterosigma akashiwo (Y. Hada) Y. Hada ex Y. Hara et M. Chihara, a cosmopolitan toxic raphidophyte. Specifically, H. akashiwo's broad salinity tolerance appears to provide a refuge from predation that enhances the net growth of H. akashiwo populations through several mechanisms. (1) Contrasting salinity tolerance of predators and prey. Estuarine H. akashiwo isolates from the west coast of North America grew rapidly at salinities as low as six, and distributed throughout experimental salinity gradients to salinities as low as three. In contrast, survival of most protistan predator species was restricted to salinities >15. (2) H. akashiwo physiological and behavioral plasticity. Acclimation to low salinity enhanced H. akashiwo's ability to accumulate and grow in low salinity waters. In addition, the presence of a ciliate predator altered H. akashiwo swimming behavior, promoting accumulation in low-salinity surface layers inhospitable to the ciliate. (3) Negative effects of low salinity on predation processes. Ciliate predation rates decreased sharply at salinities <25 and, for one species, H. akashiwo toxicity increased at low salinities. Taken together, these behaviors and responses imply that blooms can readily initiate in low salinity waters where H. akashiwo would experience decreased predation pressure while maintaining near-maximal growth rates. The salinity structure of a typical estuary would provide this HAB species a unique refuge from predation. Broad salinity tolerance in raphidophytes may have evolved in part as a response to selective pressures associated with predation.

Preoperative evaluation, premedication, and induction of anesthesia in infants and children.

PURPOSE OF REVIEW: Preparation for and induction of anesthesia in children has evolved significantly over the last decade, with particular reference to the reduction of perioperative anxiety reduction by nonpharmacologic and pharmacologic means. Several new large population studies and meta-analyses further scrutinize the current techniques. RECENT FINDINGS: Many nonpharmacologic methods to reduce anxiety are effective λU similar to sedative premedications, with the exception of parent present induction of anesthesia. Healthcare providers can be taught to increase anxiety-reducing behaviors through an educational intervention. Clonidine and dexmedetomidine have many similar or superior qualities to midazolam. SUMMARY: Larger studies still need to be conducted before wide-scale application of many nonpharmalogical interventions such as parental acupuncture. Similarly, more investigation should be done on outcomes such as onset, emergence, and discharge times, as well as the postoperative response with reference to emergence delirium and postoperative nausea and vomiting prevention to outline the differences among sedative premedications such as midazolam, clonidine, and dexmedetomidine.

A giant cell surface protein in Synechococcus WH8102 inhibits feeding by a dinoflagellate predator.

Diverse strains of the marine planktonic cyanobacterium Synechococcus sp. show consistent differences in their susceptibility to predation. We used mutants of Sargasso Sea strain WH8102 (clade III) to test the hypothesis that cell surface proteins play a role in defence against predation by protists. Predation rates by the heterotrophic dinoflagellate Oxyrrhis marina on mutants lacking the giant SwmB protein were always higher (by 1.6 to 3.9×) than those on wild-type WH8102 cells, and equalled predation rates on a clade I strain (CC9311). In contrast, absence of the SwmA protein, which comprises the S-layer (surface layer of the cell envelope that is external to the outer membrane), had no effect on predation by O. marina. Reductions in predation rate were not due to dissolved substances in Synechococcus cultures, and could not be accounted for by variations in cell hydrophobicity. We hypothesize that SwmB defends Synechococcus WH8102 by interfering with attachment of dinoflagellate prey capture organelles or cell surface receptors. Giant proteins are predicted in the genomes of multiple Synechococcus isolates, suggesting that this defence strategy may be more general. Strategies for resisting predation will contribute to the differential competitive success of different Synechococcus groups, and to the diversity of natural picophytoplankton assemblages.

Changing healthcare providers' behavior during pediatric inductions with an empirically based intervention.

BACKGROUND: Each year more than 4 million children experience significant levels of preoperative anxiety, which has been linked to poor recovery outcomes. Healthcare providers (HCPs) and parents represent key resources for children to help them manage their preoperative anxiety. The current study reports on the development and preliminary feasibility testing of a new intervention designed to change HCP and parent perioperative behaviors that have been reported previously to be associated with children's coping and stress behaviors before surgery. METHODS: An empirically derived intervention, Provider-Tailored Intervention for Perioperative Stress, was developed to train HCPs to increase behaviors that promote children's coping and decrease behaviors that may exacerbate children's distress. Rates of HCP behaviors were coded and compared between preintervention and postintervention. In addition, rates of parents' behaviors were compared between those that interacted with HCPs before training to those interacting with HCPs after the intervention. RESULTS: Effect sizes indicated that HCPs who underwent training demonstrated increases in rates of desired behaviors (range: 0.22-1.49) and decreases in rates of undesired behaviors (range: 0.15-2.15). In addition, parents, who were indirectly trained, also demonstrated changes to their rates of desired (range: 0.30-0.60) and undesired behaviors (range: 0.16-0.61). CONCLUSIONS: The intervention successfully modified HCP and parent behaviors. It represents a potentially new clinical way to decrease anxiety in children. A multisite randomized control trial funded by the National Institute of Child Health and Development will examine the efficacy of this intervention in reducing children's preoperative anxiety and improving children's postoperative recovery.

Variability in protist grazing and growth on different marine Synechococcus isolates.

Grazing mortality of the marine phytoplankton Synechococcus is dominated by planktonic protists, yet rates of consumption and factors regulating grazer-Synechococcus interactions are poorly understood. One aspect of predator-prey interactions for which little is known are the mechanisms by which Synechococcus avoids or resists predation and, in turn, how this relates to the ability of Synechococcus to support growth of protist grazer populations. Grazing experiments conducted with the raptorial dinoflagellate Oxyrrhis marina and phylogenetically diverse Synechococcus isolates (strains WH8102, CC9605, CC9311, and CC9902) revealed marked differences in grazing rates-specifically that WH8102 was grazed at significantly lower rates than all other isolates. Additional experiments using the heterotrophic nanoflagellate Goniomonas pacifica and the filter-feeding tintinnid ciliate Eutintinnis sp. revealed that this pattern in grazing susceptibility among the isolates transcended feeding guilds and grazer taxon. Synechococcus cell size, elemental ratios, and motility were not able to explain differences in grazing rates, indicating that other features play a primary role in grazing resistance. Growth of heterotrophic protists was poorly coupled to prey ingestion and was influenced by the strain of Synechococcus being consumed. Although Synechococcus was generally a poor-quality food source, it tended to support higher growth and survival of G. pacifica and O. marina relative to Eutintinnis sp., indicating that suitability of Synechococcus varies among grazer taxa and may be a more suitable food source for the smaller protist grazers. This work has developed tractable model systems for further studies of grazer-Synechococcus interactions in marine microbial food webs.