Does value-based prioritization at working memory enhance long-term memory?

Research has demonstrated that individuals can direct their attention to valuable information in both working memory and long-term memory tasks with observable effects on performance. However, it is currently unclear whether prioritising an item for a working memory task automatically translates into a boost at long-term memory. This was examined in two experiments using relatively short (250 ms per item; Experiment 1) and longer (500 ms per item; Experiment 2) encoding times. Participants first completed a visual working memory task, in which they were presented with series of photographs of everyday objects. Following a brief delay (1,000 ms), they completed a four-alternative forced-choice test. Prior to encoding, participants were informed of the point values associated with each item. In some trials, the first item in the sequence was worth more points than the rest. In other trials, all items were equally valuable. After a filled delay, participants completed a surprise long-term memory task. At working memory, a value effect was reliably observed on recognition accuracy, along with some evidence of faster response times for high-value items. However, there was little consistent evidence of this effect automatically persisting into long-term memory. Thus, the benefits of attentional prioritization in working memory do not always translate into longer-term performance. More broadly, this provides further evidence that manipulations that enhance working memory performance do not necessarily enhance long-term memory.

Reactogenicity, pregnancy outcomes, and SARS-CoV-2 infection following COVID-19 vaccination during pregnancy in Canada: A national prospective cohort study.

OBJECTIVE: To describe self-reported reactogenicity, pregnancy outcomes, and SARS-CoV-2 infection following COVID-19 vaccination during pregnancy. DESIGN: National, prospective cohort study. SETTING: Participants across Canada were enrolled from July 2021 until June 2022. POPULATION: Individuals pregnant during the COVID-19 pandemic, regardless of vaccination status, were included. METHODS: The Canadian COVID-19 Vaccine Registry for Pregnant and Lactating Individuals (COVERED) was advertised through traditional and social media. Surveys were administered at baseline, following each vaccine dose if vaccinated, pregnancy conclusion, and every two months for 14 months. Changes to pregnancy or vaccination status, SARS-CoV-2 infections, or significant health events were recorded. MAIN OUTCOME MEASURES: Reactogenicity (local and systemic adverse events, and serious adverse events) within 1 week post-vaccination, pregnancy and neonatal outcomes, and subsequent SARS-CoV-2 infection. RESULTS: Among 2868 participants who received 1-2 doses of a COVID-19 vaccine during pregnancy, adverse events described included: headache (19.5-33.9%), nausea (4.8-13.8%), fever (2.7-10.2%), and myalgia (33.4-42.2%). Reactogenicity was highest after the 2nd dose of vaccine in pregnancy. Compared to 1660 unvaccinated participants, there were no statistically significant differences in adverse pregnancy or infant outcomes, aside from an increased risk of NICU admission ≥ 24 h among the unvaccinated group. During follow-up, there was a higher rate of participant-reported SARS-CoV-2 infection in the unvaccinated compared to the vaccinated group (18[47.4%] vs. 786[27.3%]). CONCLUSIONS: Participant-reported reactogenicity was similar to reports from non-pregnant adults. There was no increase in adverse pregnancy and birth outcomes among vaccinated vs. unvaccinated participants and lower rates of SARS-CoV-2 infection were reported in vaccinated participants. TWEETABLE ABSTRACT: No significant increase in adverse pregnancy or infant outcomes among vaccinated versus unvaccinated pregnant women in Canada.

National increase in the community supply of take-home naloxone associated with a mass media campaign in Scotland: a segmented time series analysis.

BACKGROUND: Take-home naloxone (THN) programmes have been associated with reductions in opioid-related mortality. In response to high rates of drug-related deaths in Scotland, the Scottish Government commissioned the 'How to save a life' (HTSAL) mass media campaign to: (1) increase awareness of drug-related deaths and how to respond to an overdose, and (2) increase the supply of THN. The aim of this study was to assess the effect of the campaign on the supply of THN. METHODS: We used an interrupted time series design to assess the effect of the HTSAL mass media campaign on the national community supply of THN. The study time period was August 2020-December 2021. We modelled two key dates: the start of the campaign (week beginning (w/b) 30th of August 2021) and after the end of the main campaign (w/b 25th of October 2021). RESULTS: The total number of THN kits distributed in the community in Scotland during the study period was 27,064. The mean number of THN kits distributed per week (relative to the pre-campaign period), increased by 126% during the campaign and 57% post-campaign. In segmented regression analyses, the pre-campaign trend in the number of THN kits supplied was increasing by an average of 1% each week (RR=1.01, 95% CI 1.01 to 1.01, p<0.001). Once the campaign started, a significant change in level was observed, and the number of kits increased by 75% (RR=1.75, 95% CI 1.29 to 2.40, p<0.001). The trend during the campaign was stable (i.e. not increasing or decreasing) but a significant change in level was observed when the campaign ended, and the number of THN kits supplied decreased by 32% (RR=0.68, 95% CI 0.46 to 0.98, p = 0.042). The trend during the post-campaign period was stable. CONCLUSIONS: The HTSAL campaign had a short term, but large and significant impact, on the community supply of THN in Scotland. Mass media campaigns could be combined with other interventions and strategies to maintain the increased uptake of THN outside of campaign periods.

How to save a life: Public awareness of a national mass media take home naloxone campaign, and effects of exposure to campaign components on overdose knowledge and responses.

BACKGROUND: Take home naloxone (THN) programmes are effective at reducing opioid related mortality, but require high levels of distribution, including to the general public. Mass media campaigns can be effective in improving public understanding of a topic and encouraging behavior change. Whilst mass media campaigns focusing on naloxone have been developed internationally, there is a lack of research on their potential impact. We investigated the effects of components of a recent national mass media campaign (Scotland, UK) designed to improve public awareness of drug related deaths, and readiness to intervene. METHODS: We undertook a cross-sectional online experimental study with a randomized design, conducted with a nationally representative sample. Participants (N = 1551; 52.6% female; age 46.1±16.5 years) were assessed on overdose knowledge and readiness to intervene after presentation of eight combinations of campaign components. RESULTS: Compared to a basic campaign description, exposure to all types of campaign component were associated with higher overdose knowledge (p < .001), but not knowledge of what to do in response to an overdose (p = .374), or readiness to intervene (p= .286). The greatest effects were associated with a media rich audio-visual resource (animated video with a popular song on the soundtrack, and narrated by a well-known actor). CONCLUSION: Our data suggest that harm reduction is an appropriate topic for large-scale mass media campaigns. However, effects may be limited to knowledge and awareness raising in the general public, and may be related to the types of media used. Audience segmentation is important and more general messaging about drug related deaths may be more appropriate for the majority of audiences.

Influence of environmental temperature and heatwaves on surgical site infection after hip and knee arthroplasty: a nationwide study.

BACKGROUND: Previous studies reported higher incidence of surgical site infection (SSI) after procedures performed in summer or with high temperatures. However, no study used detailed climate data to assess this risk after hip and knee arthroplasty, and no study specifically investigated the role of heatwaves. AIM: To assess the impact of higher environmental temperatures and heatwaves on SSI rates after hip and knee arthroplasty. METHODS: Data on hip and knee arthroplasty procedures performed between January 2013 and September 2019 in hospitals participating in the Swiss SSI surveillance were linked to climate data extracted from weather stations located in their vicinity. The association between temperature, heatwaves and SSI was studied using mixed effects logistic regression models fitted at the patient level. Poisson mixed models were fitted for both calendar year and month of the year to investigate the SSI incidence trajectory over time. RESULTS: We included 116,981 procedures performed in 122 hospitals. Significantly higher SSI rates were observed for procedures performed in the summertime (incidence rate ratio 1.39, 95% CI (1.20-1.60), P<0.001; reference: autumn) or in calendar months in which the mean temperature was above 20 °C (reference 5-10 °C; odds ratio 1.59, 95% CI (1.27, 1.98), P<0.001). We observed a slight but non-significant increase in the rate of SSI during heatwaves (1.44% versus 1.01%, P=0.2). CONCLUSION: SSI rates after hip and knee replacement appear to increase with higher environmental temperature. To establish whether, and to what extent, heatwaves increase the risk of SSI, studies involving geographical areas with larger variability in temperature are needed.

A Bayesian spatiotemporal model for prevalence estimation of a VRE outbreak in a tertiary care hospital.

BACKGROUND: There was a nosocomial outbreak of vancomycin-resistant enterococci (VRE) at the hospital between 1st January 2018 and 31st July 2020. The goals of this study were to describe weekly prevalence, and to identify possible effects of the introduction of selected infection control measures. METHODS: A room-centric analysis of 12 floors (243 rooms) of the main hospital building was undertaken, including data on 37,558 patients over 22,072 person-weeks for the first 2 years of the outbreak (2018-2019). Poisson Bayesian hierarchical models were fitted to estimate prevalence per room and per week, including both spatial and temporal random effects terms. RESULTS: Exploratory data analysis revealed significant variability in prevalence between departments and floors, along with sporadic spatial and temporal clustering during colonization 'flare-ups'. The oncology department experienced slightly higher prevalence over the 104-week study period [adjusted prevalence ratio (aPR) 4.8, 95% confidence interval (CI) 2.6-8.9; P<0.001; compared with general medicine], as did both the cardiac surgery (aPR 3.8, 95% CI 2.0-7.3; P<0.001) and abdominal surgery (aPR 3.7, 95% CI 1.8-7.6; P<0.001) departments. Estimated peak prevalence was reached in July 2018, at which point a number of new infection control measures (including the daily disinfection of rooms and room cleaning with ultraviolet light upon patient discharge) were introduced that resulted in decreasing prevalence (aPR 0.89 per week, 95% CI 0.87-0.91; P<0.001). CONCLUSION: Relatively straightforward but personnel-intensive cleaning with disinfectants and ultraviolet light provided tangible benefits in getting the outbreak under control. Despite additional complexity, Bayesian hierarchical models provide a more flexible platform to study transmission dynamics.

'Pretty in Pink' and 'Girl Power': An analysis of the targeting and representation of women in alcohol brand marketing on Facebook and Instagram.

BACKGROUND: Alcohol marketing helps shape how gender roles and relations are understood, and the gendered nature of drinking learned. In recent years, changes in how women are presented and addressed in marketing, including alcohol marketing, have been observed. This reflects the shifting social, political and regulatory context, in which increased attention has been given to gender inequality and the damaging impact of gender stereotypes. Research is yet to explore the gendered nature of alcohol marketing within this contemporary context. METHODS: A quantitative content and qualitative thematic analysis of alcohol marketing posts (N = 2600) by 20 alcohol brands on Facebook and Instagram pages over an 18 month period (1st January 2019-30th June 2020) was conducted. Marketing strategies were identified, and the way in which posts targeted, represented and engaged women analysed. FINDINGS: New (e.g. 'influencer' collaborations) and established (e.g. competitions) strategies were being used to target both women and men. Drinking was presented as a feminine practice and as an important component of 'doing' a combination of traditional, post-feminist and feminist femininities. Women were assigned a range of gender roles that acknowledged their individual pleasures and achievements, and traditional gender roles and stereotypes were both reinforced and rejected to promote alcohol use. An important move away from sexualising and demeaning women to the appropriation of feminist and equality messages was observed, which may appeal to a wider range of women, including those embracing feminist identities. CONCLUSION: Alcohol brand marketing encourages alcohol use to women through both perpetuating and challenging gender stereotypes. Claims by brands of a commitment to equality are at odds with the harms related to alcohol consumption that contribute to the widening of health and social inequalities. It is important that future work on women's drinking and alcohol marketing is situated within the shifting social-political climate in which traditional, post-feminist and new fourth wave feminist rhetoric and femininities co-exist.

Performance and image enhancing drug interventions aimed at increasing knowledge among healthcare professionals (HCP): reflections on the implementation of the Dopinglinkki e-module in Europe and Australia in the HCP workforce.

BACKGROUND: Healthcare professionals (HCPs) provide an important point of contact through which people who use performance and image enhancing drugs (PIEDs) could access reliable information, advice, and interventions on a range of PIEDs, their use and related harms. However, HCPs often report difficulties engaging and building rapport with people who use PIEDs, and research suggests that they often lack specialist knowledge on these substances. Providing credible evidence-based resources to support HCPs is thus important. However, educational materials in this area are generally absent and the ones that exist have not been assessed for their utility in the HCP workforce. This paper examines the acceptability and usability of a PIED e-learning module (the Dopinglinkki e-module) targeted at HCPs in three EU Member States and Australia. METHODS: A standardised two stage, mixed methodology was implemented. Stage 1 involved HCPs completing the e-module and completing an online survey (N = 77). Stage 2 involved conducting individual structured interviews with a subset of survey respondents (N = 37). Normalisation Process Theory and the Theoretical Framework of Acceptability were used as conceptual lenses. FINDINGS: The e-module provided information that was perceived as useful for HCPs' current and future practice. However, several individual, organisational and societal level barriers were reported as preventing the e-module becoming an accepted and normalised aspect of the HCP workforce, including the need for up to date evidence, the time-consuming nature of completing the e-module, lack of organisational support, the use of over-complex language, and the module's potential to reinforce the stigmatisation of PIEDs. CONCLUSION: Providing credible evidence-based resources to support HCPs' knowledge development is important. Evidence-based and theory informed interventions are needed to equip HCPs with knowledge that can aid culturally sensitive interactions and effective engagement with people who use PIEDs. Reflecting on our study findings, it is important that the development of interventions should include the voices of both HCP and those using PIEDs, and that careful consideration is given to the various factors that may act as a barrier to effective implementation.

Common arterial trunk in a cat: a high-resolution morphological analysis with micro-computed tomography.

A 6-month-old female cat presented with respiratory distress. Physical examination showed a grade 5/6 holosystolic murmur with prominent precordial impulse over the left cranial chest wall. Echocardiography revealed bilateral hypertrophy of the ventricular walls, a dilated ascending aorta overriding the interventricular septum, a membranous ventricular septal defect and no obvious pulmonary trunk or pulmonary artery branches. Turbulent blood flow was detected around the ventricular septal defect and ascending aorta. Follow-up assessment, 12 months later, revealed marked and progressive biatrial dilation and biventricular hypertrophy. Four months after that, the cat died of severe congestive heart failure. To make a definitive postmortem diagnosis, we performed contrast enhanced micro-computed tomography (CT) on the ex vivo heart with micron-scale spatial resolution imaging and three-dimensional reconstruction. Micro-computed tomography analysis confirmed a common arterial trunk that bifurcated into the left pulmonary artery and aorta 5-mm distally from the truncal valve. The pulmonary trunk was absent. Slightly distal to the first branching, the common arterial trunk further branched into the right pulmonary artery and ascending aorta, indicating the aortic dominant form. Although CT angiography would be a preferred imaging modality for living animals, micro-computed tomography is a valuable tool for the ex vivo diagnosis of complex cardiac anomaly, such as presented in this cat.

Evaluation of Ultra-low-dose Paediatric Cone-beam Computed Tomography for Image-guided Radiotherapy.

AIMS: In image-guided radiotherapy, daily cone-beam computed tomography (CBCT) is rarely applied to children due to concerns over imaging dose. Simulating low-dose CBCT can aid clinical protocol design by allowing visualisation of new scan protocols in patients without delivering additional dose. This work simulated ultra-low-dose CBCT and evaluated its use for paediatric image-guided radiotherapy by assessment of image registration accuracy and visual image quality. MATERIALS AND METHODS: Ultra-low-dose CBCT was simulated by adding the appropriate amount of noise to projection images prior to reconstruction. This simulation was validated in phantoms before application to paediatric patient data. Scans from 20 patients acquired at our current clinical protocol (0.8 mGy) were simulated for a range of ultra-low doses (0.5, 0.4, 0.2 and 0.125 mGy) creating 100 scans in total. Automatic registration accuracy was assessed in all 100 scans. Inter-observer registration variation was next assessed for a subset of 40 scans (five scans at each simulated dose and 20 scans at the current clinical protocol). This subset was assessed for visual image quality by Likert scale grading of registration performance and visibility of target coverage, organs at risk, soft-tissue structures and bony anatomy. RESULTS: Simulated and acquired phantom scans were in excellent agreement. For patient scans, bony atomy registration discrepancies for ultra-low-dose scans fell within 2 mm (translation) and 1° (rotation) compared with the current clinical protocol, with excellent inter-observer agreement. Soft-tissue registration showed large discrepancies. Bone visualisation and registration performance reached over 75% acceptability (rated 'well' or 'very well') down to the lowest doses. Soft-tissue visualisation did not reach this threshold for any dose. CONCLUSION: Ultra-low-dose CBCT was accurately simulated and evaluated in patient data. Patient scans simulated down to 0.125 mGy were appropriate for bony anatomy set-up. The large dose reduction could allow for more frequent (e.g. daily) image guidance and, hence, more accurate set-up for paediatric radiotherapy.

Effects of messaging on public support for drug consumption rooms in scotland, UK.

BACKGROUND: There is evidence to suggest that medically supervised drug consumption rooms (DCRs) may form part of responses to reduce drug-related harm. Although DCRs have been established globally, they are perceived by some to be a controversial approach in the UK, and Government has repeatedly rejected proposals to establish one in Glasgow, Scotland. As public support is an important component of policy development and enactment, we sought to investigate the effects of different types of message framing on public support for DCR. METHODS: We undertook a cross-sectional online study with a randomised design, conducted with a nationally representative sample. Participants were randomised to one of six message conditions comprising combinations of four components. All conditions included i) a basic description of a DCR, and conditions included combinations of ii) factual information; iii) pre-emptive refutation of common public concerns about DCR; and/or iv) a sympathetic narrative describing a mother whose son died from a heroin overdose. After reading each message, participants completed a bespoke measure assessing support for DCR. Data were analysed using ANCOVA. RESULTS: Complete data were obtained from 1591 participants (50.3% Female; mean age 44.9 ± 16.1 years). Compared to reading a basic description of DCR alone, there was greater support for DCR in participants receiving the refutation (p < .001); sympathetic + factual (p < .05); and sympathetic + factual + refutation (p < .001) message conditions. Presenting factual or sympathetic messages alone were not associated with increased support. CONCLUSION: Our findings suggest that public support for DCRs is not improved through communication of factual statements outlining potential benefits of the intervention alone. Advocates seeking to foster public support, and thus influence policy making, should also consider communication campaigns that address common concerns that the public might have about DCRs, and present the intervention in relation to potential benefits that they hold for people indirectly affected by drug-related harm.

Impact of an evidence-based intervention on urinary catheter utilization, associated process indicators, and infectious and non-infectious outcomes.

BACKGROUND: Multi-centre intervention studies tackling urinary catheterization and its infectious and non-infectious complications are lacking. AIM: To decrease urinary catheterization and, consequently, catheter-associated urinary tract infections (CAUTIs) and non-infectious complications. METHODS: Before/after non-randomized multi-centre intervention study in seven hospitals in Switzerland. Intervention bundle consisting of: (1) a concise list of indications for urinary catheterization; (2) daily evaluation of the need for ongoing catheterization; and (3) education on proper insertion and maintenance of urinary catheters. The primary outcome was urinary catheter utilization. Secondary outcomes were CAUTIs, non-infectious complications and process indicators (proportion of indicated catheters and frequency of catheter evaluation). FINDINGS: In total, 25,880 patients were included in this study [13,171 at baseline (August-October 2016) and 12,709 post intervention (August-October 2017)]. Catheter utilization decreased from 23.7% to 21.0% (P=0.001), and catheter-days per 100 patient-days decreased from 17.4 to 13.5 (P=0.167). CAUTIs remained stable at a low level with 0.02 infections per 100 patient-days (baseline) and 0.02 infections (post intervention) (P=0.98). Measuring infections per 1000 catheter-days, the rate was 1.02 (baseline) and 1.33 (post intervention) (P=0.60). Non-infectious complications decreased significantly, from 0.79 to 0.56 events per 100 patient-days (P<0.001), and from 39.4 to 35.4 events per 1000 catheter-days (P=0.23). Indicated catheters increased from 74.5% to 90.0% (P<0.001). Re-evaluations increased from 168 to 624 per 1000 catheter-days (P<0.001). CONCLUSION: A straightforward bundle of three evidence-based measures reduced catheter utilization and non-infectious complications, whereas the proportion of indicated urinary catheters and daily evaluations increased. The CAUTI rate remained unchanged, albeit at a very low level.

Cefepime neurotoxicity: thresholds and risk factors. A retrospective cohort study.

OBJECTIVES: Toxic serum cefepime trough concentrations are not well defined in the current literature. We aimed to define a more precise plasma trough concentration threshold for this antibiotic's neurological toxicity and to identify individuals at risk for developing neurotoxic side effects. METHODS: Retrospective study including all individuals who underwent cefepime therapeutic drug monitoring (TDM) between 2013 and 2017. Individuals with cefepime concentrations other than trough were excluded. The primary outcome was to assess the incidence of neurotoxicity and its relationship with cefepime plasma trough concentrations. Secondary outcomes were the relationship of renal function, cefepime daily dose, age, and cerebral and general co-morbidities with the occurrence of neurotoxicity. We also compared the mortality rate during hospitalization in individuals with and without neurotoxicity, and the possible impact of neuroprotective co-medications on outcomes. RESULTS: Cefepime concentrations were determined in 584 individuals. Among 319 individuals with available trough concentrations included, the overall incidence of neurotoxicity was 23.2% (74 of 319 individuals). Higher cefepime plasma trough concentrations were significantly associated with risk of neurotoxicity (no neurotoxicity 6.3 mg/L (interquartile range (IQR) 4.1-8.6) versus with neurotoxicity 21.6 mg/L (IQR 17.0-28.6), p <0.001). Individuals with presumed cefepime neurotoxicity had a significantly lower renal function (estimated glomerular filtration rate 82.0 mL/min/1.73 m2 (IQR 45.0-105.0) versus 35.0 mL/min/1.73 m2 (IQR 23.3-53.3], p <0.001), and significantly higher in-hospital mortality (19 (7.8%) versus 26 (35.1%) individuals, p <0.001). No neurotoxic side effects were seen below a trough concentration of 7.7 mg/L. Levels ≥38.1 mg/L always led to neurological side effects. CONCLUSION: In individuals with risk factors for cefepime neurotoxicity, such as renal insufficiency, TDM should be systematically performed, aiming at trough concentrations <7.5 mg/L.

Author Correction: The importance of Antarctic krill in biogeochemical cycles.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The importance of Antarctic krill in biogeochemical cycles.

Antarctic krill (Euphausia superba) are swarming, oceanic crustaceans, up to two inches long, and best known as prey for whales and penguins - but they have another important role. With their large size, high biomass and daily vertical migrations they transport and transform essential nutrients, stimulate primary productivity and influence the carbon sink. Antarctic krill are also fished by the Southern Ocean's largest fishery. Yet how krill fishing impacts nutrient fertilisation and the carbon sink in the Southern Ocean is poorly understood. Our synthesis shows fishery management should consider the influential biogeochemical role of both adult and larval Antarctic krill.

'We are still obsessed by this idea of abstinence': A critical analysis of UK news media representations of proposals to introduce drug consumption rooms in Glasgow, UK.

BACKGROUND: Drug consumptions rooms (DCRs) are a well-established and evidence-based harm reduction response to drug use. Recently, a consortium led by health services in Glasgow, United Kingdom (UK), proposed piloting a DCR. In this article, we examine how the proposals were represented in news media reporting, and the possible effects of such reporting. METHODS: A quantitative content and qualitative thematic analysis of UK news media (n = 174 articles) representations of the proposals to introduce DCRs in the city of Glasgow, UK, was conducted. Analysis was informed by Bacchi's (2009, 2012, 2017) approach to policy analysis, 'What's the problem represented to be?' FINDINGS: Competing representations of the 'problem' of injecting drug use (IDU) were contested by a range of actors with different political visions. The applicability of the 'evidence base', potential benefits of DCRs to both users and the public, and the associated economic costs, were presented in differing ways depending on the underlying assumptions and presumptions of the arguments constructed (e.g. harm reduction vs recovery). As a result, a number of conflicting subject positions were presented that may have implications for the way that people who inject drugs (PWID) see themselves, and how they are viewed and treated by society. Whilst proponents positioned DCRs within a discourse of public health, an underlying rhetoric of abstinence and recovery underpinned the arguments against DCRs. It was this latter discourse that underpinned the UK Government's rejection of the proposals, which the Scottish Government were prevented from overruling within the political constraints of their devolved powers, with the lived effect of people who use drugs (PWUD) being denied access to public health services that mitigate harm. CONCLUSION: We conclude that attempts to introduce and gain public and political support for harm reduction responses such as DCRs through the news media face challenges within the historical and political context of prohibitionist UK drugs policy.

Krill faecal pellets drive hidden pulses of particulate organic carbon in the marginal ice zone.

The biological carbon pump drives a flux of particulate organic carbon (POC) through the ocean and affects atmospheric levels of carbon dioxide. Short term, episodic flux events are hard to capture with current observational techniques and may thus be underrepresented in POC flux estimates. We model the potential hidden flux of POC originating from Antarctic krill, whose swarming behaviour could result in a major conduit of carbon to depth through their rapid exploitation of phytoplankton blooms and bulk egestion of rapidly sinking faecal pellets (FPs). Our model results suggest a seasonal krill FP export flux of 0.039 GT C across the Southern Ocean marginal ice zone, corresponding to 17-61% (mean 35%) of current satellite-derived export estimates for this zone. The magnitude of our conservatively estimated flux highlights the important role of large, swarming macrozooplankton in POC export and, the need to incorporate such processes more mechanistically to improve model projections.

Characterizing non-linear effects of hospitalisation duration on antimicrobial resistance in respiratory isolates: an analysis of a prospective nationwide surveillance system.

OBJECTIVES: Our objective was to systematically study the influence of length of hospital stay on bacterial resistance in relevant respiratory tract isolates. METHODS: Using prospective epidemiological data from the National Swiss Antibiotic Resistance Surveillance System, susceptibility testing results for respiratory isolates retrospectively retrieved from patients hospitalised between 2008 and 2014 were compiled. Generalized additive models were used to illustrate resistance rates relative to hospitalisation duration and to adjust for co-variables. RESULTS: In all, 19 622 isolates of six relevant and predominant species were included. Resistance patterns for the predominant species showed a species-specific and antibiotic-resistance-specific profile in function of hospitalisation duration. The oxacillin resistance profile in Staphylococcus aureus isolates was constantly increasing (monophasic). The pattern of resistance to cefepime in Pseudomonas aeruginosa was biphasic with a decreasing resistance rate for the first 5 days of hospitalisation and an increase for days 6-30. A different biphasic pattern occurred in Escherichia coli regarding amoxicillin-clavulanic acid resistance: odds/day increased for the first 7 days of hospitalisation and then remained stable for days 8-30. In the adjusted models epidemiological characteristics such as age, ward type, hospital type and linguistic region were identified as relevant co-variables for the resistance rates. The contribution of these confounders was specific to the individual species/antibiotic resistance models. CONCLUSIONS: Resistance rates do not follow a dichotomic pattern (early versus late nosocomial) as suggested by current hospital-acquired pneumonia treatment guidelines. Duration of hospitalisation rather appears to have a more complex and non-linear relationship with bacterial resistance in hospital-acquired pneumonia, also depending on host and environmental factors.

Low incidence of subsequent bacteraemia or fungaemia after removal of a colonized intravascular catheter tip.

OBJECTIVES: We determined the frequency of subsequent bloodstream infection more than 2 days after removal of a catheter with positive tip cultures. METHODS: We conducted a nationwide, observational study on intravascular catheter (IVC) tip cultures in Switzerland from 2008 to 2015 using data from the Swiss Antibiotic Resistance Surveillance System (ANRESIS). An IVC tip culture was included in the analysis if at least one microorganism could be cultivated from it. We excluded all data from patients with concurrent bacteraemia with the same microorganism identified 7 days before to 2 days after IVC removal. Subsequent bloodstream infection was defined as isolating (from blood cultures performed more than 2 days up to 7 days after catheter removal) the same microorganism as the one recovered from the IVC. Data on antibiotic therapy were not available in this surveillance study. RESULTS: Over the 8-year period, 15 033 positive IVC tip cultures were identified. Our study population comprised 12 513 episodes of positive IVC tip cultures without concurrent bacteraemia. The frequency of sBSI was 1.8% (n = 219). Subsequent bloodstream infections were more frequently detected after identification of C. albicans (10/113, 8.8%), S. marcescens (9/169, 5.3%), and S. aureus (30/623, 4.8%) on a catheter tip. CONCLUSIONS: A very low incidence of subsequent bloodstream infection was observed if a microorganism was identified on a removed IVC tip without concurrent bacteraemia. The risk of subsequent bloodstream infection increased if C. albicans, S. aureus, or S. marcescens were identified in this context.

Laser-preparation of geometrically optimised samples for X-ray nano-CT.

A robust and versatile sample preparation technique for the fabrication of cylindrical pillars for imaging by X-ray nano-computed tomography (nano-CT) is presented. The procedure employs simple, cost-effective laser micro-machining coupled with focused-ion beam (FIB) milling, when required, to yield mechanically robust samples at the micrometre length-scale to match the field-of-view (FOV) for nano-CT imaging. A variety of energy and geological materials are exhibited as case studies, demonstrating the procedure can be applied to a variety of materials to provide geometrically optimised samples whose size and shape are tailored to the attenuation coefficients of the constituent phases. The procedure can be implemented for the bespoke preparation of pillars for both lab- and synchrotron-based X-ray nano-CT investigations of a wide range of samples.