Characterization of Healthcare-Associated and Community-Associated Clostridioides difficile Infections among Adults, Canada, 2015-2019

We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.

Resprouters Versus Reseeders: Are Wild Rooibos Ecotypes Genetically Distinct?

Aspalathus linearis (Burm. F.) R. Dahlgren (Fabaceae) or rooibos, is a strict endemic species, limited to areas of the Cederberg (Western Cape) and the southern Bokkeveld plateau (Northern Cape) in the greater Cape Floristic Region (CFR) of South Africa. Wild rooibos, unlike the cultivated type, is variable in morphology, biochemistry, ecology and genetics, and these ecotypes are broadly distinguished into two main groups, namely, reseeders and resprouters, based on their fire-survival strategy. No previous assessment of genetic diversity or population structure using microsatellite markers has been conducted in A. linearis. This study aimed to test the hypothesis that wild rooibos ecotypes are distinct in genetic variability and that the ecotypes found in the Northern Cape are differentiated from those in the Cederberg that may be linked to a fire-survival strategy as well as distinct morphological and phytochemical differences. A phylogeographical and population genetic analyses of both chloroplast (trnLF intergenic region) and newly developed species-specific nuclear markers (microsatellites) was performed on six geographically representative wild rooibos populations. From the diversity indices, it was evident that the wild rooibos populations have low-to-moderate genetic diversity (He: 0.618-0.723; Ho: 0.528-0.704). The Jamaka population (Cederberg, Western Cape) had the lowest haplotype diversity (H = 0.286), and the lowest nucleotide diversity (π = 0.006) even though the data revealed large variations in haplotype diversity (h = 0.286-0.900) and nucleotide diversity (π = 0.006-0.025) between populations and amongst regions where wild rooibos populations are found. Our data suggests that populations of rooibos become less diverse from the Melkkraal population (Suid Bokkeveld, Northern Cape) down towards the Cederberg (Western Cape) populations, possibly indicative of clinal variation. The largest genetic differentiation was between Heuningvlei (Cederberg, Western Cape) and Jamaka (FST = 0.101) localities within the Cederberg mountainous region, and, Blomfontein (Northern Cape) and Jamaka (Cederberg) (FST = 0.101). There was also a significant isolation by distance (R2 = 0.296, p = 0.044). The presence of three main clusters is also clearly reflected in the discriminant analysis of principal components (DAPC) based on the microsatellite marker analyses. The correct and appropriate management of wild genetic resources of the species is urgently needed, considering that the wild Cederberg populations are genetically distinct from the wild Northern Cape plants and are delineated in accordance with ecological functional traits of reseeding or resprouting, respectively. The haplotype divergence of the ecotypes has also provided insights into the genetic history of these populations and highlighted the need for the establishment of appropriate conservation strategies for the protection of wild ecotypes.

The founder sociality hypothesis

In this review, we propose that the social dynamics of founder populations in novel and newly available environments can have critical effects in shaping species' sociality and can produce long-lasting changes in social structure and behavior. For founder populations which expand into an underexploited niche separated from the parent population, the necessity of bond formation with strangers, lack of clear territories, and initial abundance of resources can lead to altered initial social dynamics to which subsequent generations adapt. We call this the founder sociality hypothesis. After specifying the theoretical reasoning and mechanism of effect, we focus on three particular cases where the social dynamics of founder populations may have a central role in explaining their modern behavioral ecology. In particular, we develop and review evidence for three predictions of the founder sociality hypothesis in territorial, mixed-sex group forming species: relatively stronger social bonds in the dispersing sex with relatively weaker bonds in the nondispersing sex, reduced territoriality, and increased social tolerance. We briefly touch on the implications for human evolution given our species' evolutionary history marked by frequent expansion and adaptation to novel environments. We conclude by proposing several experiments and models with testable predictions following from the founder sociality hypothesis.

The Impact of Transparency and Decision Risk on Human-Automation Teaming Outcomes

OBJECTIVE

Examine the effects of decision risk and automation transparency on the accuracy and timeliness of operator decisions, automation verification rates, and subjective workload.

BACKGROUND

Decision aids typically benefit performance, but can provide incorrect advice due to contextual factors, creating the potential for automation disuse or misuse. Decision aids can reduce an operator's manual problem evaluation, and it can also be strategic for operators to minimize verifying automated advice in order to manage workload.

METHOD

Participants assigned the optimal unmanned vehicle to complete missions. A decision aid provided advice but was not always reliable. Two levels of decision aid transparency were manipulated between participants. The risk associated with each decision was manipulated using a financial incentive scheme. Participants could use a calculator to verify automated advice; however, this resulted in a financial penalty.

RESULTS

For high- compared with low-risk decisions, participants were more likely to reject incorrect automated advice and were more likely to verify automation and reported higher workload. Increased transparency did not lead to more accurate decisions and did not impact workload but decreased automation verification and eliminated the increased decision time associated with high decision risk.

CONCLUSION

Increased automation transparency was beneficial in that it decreased automation verification and decreased decision time. The increased workload and automation verification for high-risk missions is not necessarily problematic given the improved automation correct rejection rate.

APPLICATION

The findings have potential application to the design of interfaces to improve human-automation teaming, and for anticipating the impact of decision risk on operator behavior.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Knowledge-based enrichment: Development of a novel enrichment device for captive chimpanzees

The field of environmental enrichment has grown considerably, but most enrichment is still focused on tasks where highly valued food rewards are directly visible. We designed a device which would instead make use of knowledge states, motivational structure, and physical reasoning skills and could use hidden, low-quality food items while remaining low in cost. Food items were hidden in small cardboard tubes and placed snugly inside another, larger, tube such that they were difficult to extract and presented a challenging dexterity and physical reasoning task. Rare favored food items were distributed so animals would be rewarded at irregular intervals. The devices were then presented to two groups of chimpanzees (Pan troglodytes) who either had experience extracting food from identical small cardboard tubes or had no such experience. We found that the chimpanzees with no prior experience with the small tubes used the device very little until one individual removed a small tube, revealing the food inside, at which point use time significantly increased. In the knowledgeable group, no change was observed after the first tube retrieval. Individuals in both groups used the devices for over 20 min each on average over a 1-h observation period, and in both facilities at least one device still contained all inner tubes. Our study suggests that enrichment can make use of animals' prior knowledge, that enrichment devices can thus be layered into one another, and reiterates the importance of considering animals' psychology in designing enrichment.

Suicidality in women with Premenstrual Dysphoric Disorder: a systematic literature review

Previous research has identified how menstruation is an important factor in both attempted and completed suicides for women. The purpose of this review was to outline (a) the risk profile for suicidality in women who were identified to experience Premenstrual Dysphoric Disorder (PMDD), a condition characterized by severe physical and psychological changes that occur during the luteal menstrual phase, and (b) the implications of these findings for clinical practice. A systematic literature review was conducted using five databases to identify any peer-reviewed articles published between 1989 and 2019. Ten papers eligible for inclusion were identified: three pertaining to suicide cognitions, five to suicide attempts and two to both cognitions and attempts. Findings showed that suicidal thoughts, ideation, plans and attempts were strongly associated with experiences of PMDD and that these findings were independent of psychiatric co-morbidities. However, women with PMDD did not present with more severe risk profiles for suicide attempts (in terms of frequency, impulsivity and lethality) or make more frequent attempts during the luteal menstrual phase compared with suicide attempters without PMDD. Women with PMDD should be considered a high risk group for suicidality; thus, identifying and treating symptoms are vital in reducing suicide attempts. Implications for clinical practice are outlined in the discussion.

Divergent effects of oxytocin on eye contact in bonobos and chimpanzees

Oxytocin has drawn significant research attention for its role in modulating mammalian social behavior. Despite generally conserved roles, oxytocin can function differently even in closely related species. Previous studies have shown that bonobos and chimpanzees, humans' two closest relatives, demonstrate considerable behavioral differences, including that bonobos look more at others' eyes than chimpanzees. Oxytocin is known to increase attention to another's eyes in many mammalian species (e.g. dogs, monkeys, and humans), yet this effect has not been tested in any nonhuman great ape species. This study examined how intranasally-administered oxytocin affects eye contact in bonobos and chimpanzees using eye tracking. Following administration of either oxytocin or saline control with a nebulizer, chimpanzees (n = 6) and bonobos (n = 5) were shown images of conspecific faces while their eye movement was recorded. Oxytocin changed the eye-looking behavior of bonobos and chimpanzees differently. We found that oxytocin increased eye contact in bonobos but not chimpanzees; while one chimpanzee showed an increase, interestingly, 5 out of 6 chimpanzees showed decreased looking to the eyes compared to the mouth, suggesting moderate eye avoidance. Given the importance of eye contact in their social interactions, our results suggest that oxytocin may play modulatory roles in bonobos' and chimpanzees' species-specific social behavior and underscore the importance of oxytocin in hominid social evolution.

The 4-Hour Cairns Sepsis Model: A novel approach to predicting sepsis mortality at intensive care unit admission

BACKGROUND

Sepsis commonly causes intensive care unit (ICU) mortality, yet early identification of adults with sepsis at risk of dying in the ICU remains a challenge.

OBJECTIVE

The aim of the study was to derive a mortality prediction model (MPM) to assist ICU clinicians and researchers as a clinical decision support tool for adults with sepsis within 4 h of ICU admission.

METHODS

A cohort study was performed using 500 consecutive admissions between 2014 and 2018 to an Australian tertiary ICU, who were aged ≥18 years and had sepsis. A total of 106 independent variables were assessed against ICU episode-of-care mortality. Multivariable backward stepwise logistic regression derived an MPM, which was assessed on discrimination, calibration, fit, sensitivity, specificity, and predictive values and bootstrapped.

RESULTS

The average cohort age was 58 years, the Acute Physiology and Chronic Health Evaluation III-j severity score was 72, and the case fatality rate was 12%. The 4-Hour Cairns Sepsis Model (CSM-4) consists of age, history of renal disease, number of vasopressors, Glasgow Coma Scale, lactate, bicarbonate, aspartate aminotransferase, lactate dehydrogenase, albumin, and magnesium with an area under the receiver operating characteristic curve of 0.90 (95% confidence interval = 0.84-0.95, p < 0.00001), a Nagelkerke R² of 0.51, specificity of 0.94, a negative predictive value of 0.98, and almost identical odds ratios during bootstrapping. The CSM-4 outperformed existing MPMs tested on our data set. The CSM-4 also performed similar to existing MPMs in their derivation papers whilst using fewer, routinely collected, and inexpensive variables.

CONCLUSIONS

The CSM-4 is a newly derived MPM for adults with sepsis at ICU admission. It displays excellent discrimination, calibration, fit, specificity, negative predictive value, and bootstrapping values whilst being easy to use and inexpensive. External validation is required.

Regulatory network analysis of Paneth cell and goblet cell enriched gut organoids using transcriptomics approaches

The epithelial lining of the small intestine consists of multiple cell types, including Paneth cells and goblet cells, that work in cohort to maintain gut health. 3D in vitro cultures of human primary epithelial cells, called organoids, have become a key model to study the functions of Paneth cells and goblet cells in normal and diseased conditions. Advances in these models include the ability to skew differentiation to particular lineages, providing a useful tool to study cell type specific function/dysfunction in the context of the epithelium. Here, we use comprehensive profiling of mRNA, microRNA and long non-coding RNA expression to confirm that Paneth cell and goblet cell enrichment of murine small intestinal organoids (enteroids) establishes a physiologically accurate model. We employ network analysis to infer the regulatory landscape altered by skewing differentiation, and using knowledge of cell type specific markers, we predict key regulators of cell type specific functions: Cebpa, Jun, Nr1d1 and Rxra specific to Paneth cells, Gfi1b and Myc specific for goblet cells and Ets1, Nr3c1 and Vdr shared between them. Links identified between these regulators and cellular phenotypes of inflammatory bowel disease (IBD) suggest that global regulatory rewiring during or after differentiation of Paneth cells and goblet cells could contribute to IBD aetiology. Future application of cell type enriched enteroids combined with the presented computational workflow can be used to disentangle multifactorial mechanisms of these cell types and propose regulators whose pharmacological targeting could be advantageous in treating IBD patients with Crohn's disease or ulcerative colitis.

Dog Stick Chewing: An Overlooked Instance of Tool Use?

Tool use is a central topic in research on cognitive evolution and behavioral ecology in non-human animals. Originally thought to be a uniquely human phenomenon, many other species have been observed making and using tools for a variety of purposes, starting with Goodall's (1964) groundbreaking work with chimpanzees in Gombe. Despite the frequent attention and great research interest in animal tool use, and ubiquity of the behavior, we argue here that chewing sticks by dogs (and other animals) should be included as a case of tool use. We discuss alternate possible explanations and then propose several testable predictions regarding this hypothesis. We suggest that tool use may be more common than is often assumed and that many cases of animal tool use may be overlooked.

Effect of automation transparency in the management of multiple unmanned vehicles

Automated decision aids can undoubtedly benefit system performance, but have the potential to provide incorrect advice, creating the possibility for automation disuse or misuse. This paper examined the extent to which increased automation transparency could improve the accuracy of automation use in a simulation of unmanned vehicle control. Participants were required to assign the best unmanned vehicle to complete missions. An automated recommender system provided advice but was not always reliable. Three levels of automation transparency were manipulated between-participants. Providing transparency regarding the reasoning underlying automated recommendations improved the accuracy of automation use, with no cost to decision time or subjective workload. Higher transparency in the form of projected decision outcome visualizations led to faster decisions, but less accurate automation use and an automation bias. Implications for the design of transparent interfaces to improve human-autonomy teaming outcomes in time-pressured environments are discussed.

The Evolution of Primate Short-Term Memory

Short-term memory is implicated in a range of cognitive abilities and is critical for understanding primate cognitive evolution. To investigate the effects of phylogeny, ecology and sociality on short-term memory, we tested the largest and most diverse primate sample to date (421 non-human primates across 41 species) in an experimental delayed-response task. Our results confirm previous findings that longer delays decrease memory performance across species and taxa. Our analyses demonstrate a considerable contribution of phylogeny over ecological and social factors on the distribution of short-term memory performance in primates; closely related species had more similar short-term memory abilities. Overall, individuals in the branch of Hominoidea performed better compared to Cercopithecoidea, who in turn performed above Platyrrhini and Strepsirrhini. Interdependencies between phylogeny and socioecology of a given species presented an obstacle to disentangling the effects of each of these factors on the evolution of short-term memory capacity. However, this study offers an important step forward in understanding the interspecies and individual variation in short-term memory ability by providing the first phylogenetic reconstruction of this trait’s evolutionary history. The dataset constitutes a unique resource for studying the evolution of primate cognition and the role of short-term memory in other cognitive abilities.

Quantum Backaction on kg-Scale Mirrors: Observation of Radiation Pressure Noise in the Advanced Virgo Detector

The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise.

GW190521: A Binary Black Hole Merger with a Total Mass of 150 M_{⊙}

On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a short duration gravitational-wave signal, GW190521, with a three-detector network signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1 in 4900 yr using a search sensitive to generic transients. If GW190521 is from a quasicircular binary inspiral, then the detected signal is consistent with the merger of two black holes with masses of 85_{-14}^{+21}  M_{⊙} and 66_{-18}^{+17}  M_{⊙} (90% credible intervals). We infer that the primary black hole mass lies within the gap produced by (pulsational) pair-instability supernova processes, with only a 0.32% probability of being below 65  M_{⊙}. We calculate the mass of the remnant to be 142_{-16}^{+28}  M_{⊙}, which can be considered an intermediate mass black hole (IMBH). The luminosity distance of the source is 5.3_{-2.6}^{+2.4}  Gpc, corresponding to a redshift of 0.82_{-0.34}^{+0.28}. The inferred rate of mergers similar to GW190521 is 0.13_{-0.11}^{+0.30}  Gpc^{-3} yr^{-1}.

Single Center Outcomes of Carotid Artery Stenting in Veterans with Prior Head and Neck Cancer

BACKGROUND

Patients meeting criteria for intervention of carotid stenosis with a history of prior cervical radiation or neck dissection are considered "high risk" for carotid endarterectomy. This is a well-established indication for carotid artery stenting (CAS). The long-term outcomes of CAS in this population are less frequently published in the literature but are poor. The purpose of this study was to review long-term results of CAS in veteran patients with a prior history of treatment for head and/or neck cancer.

METHODS

This is a retrospective review of a veteran patient population from 1998 to 2016. All patients at our institution with a prior history of treatment for head and/or neck cancer who underwent CAS were included in the analysis. During this time period, 44 patients met inclusion criteria and were treated with 57 carotid stenting interventions. The Kaplan-Meier analysis was used to determine survival and primary patency. The secondary aims were to analyze early outcomes and to identify predictive risk factors for mortality and reintervention.

RESULTS

The mean follow-up was 42.9 ± 36.6 months. The cumulative survival at 1, 5, and 10 years was 91%, 67%, and 48%, respectively. The primary patency at 1, 5, and 10 years was 95%, 86%, and 86%, respectively. The reintervention rate was 11% (n = 6) with an assisted primary patency rate of 100%. No neurologic events occurred within 30 days. There were 3 strokes in late follow-up and no stroke-related deaths. Eighteen patients (41%) died during the follow-up period, 15 of whom died during the first 5 years of follow-up. Ten (66%) of those patients died of recurrent or active index cancer. On univariate analysis, tumor, node, metastasis stage IV was significantly associated with death (P = 0.02). Multivariate models were not statistically significant for predicting mortality or reintervention CONCLUSIONS: On the basis of the results in this series, CAS can be performed in these patients with low long-term rates of neurologic events and need for reintervention. However, the survival of patients with head and neck cancer undergoing CAS in this cohort is poor, which is consistent with other published series of patients undergoing CAS for head/neck cancer with at least 5-year follow-up. In this specific patient population, a more critical analysis of the patient's overall prognosis, especially as related to cancer, should be undertaken before offering CAS.

1004 Smith-&lt;Magenis Syndrome (SMS) Circadian Abnormalities And Biological Rhythms

Introduction

SMS is a rare neurodevelopmental disorder that manifests with craniofacial abnormalities, behavioral disturbances, and a severe sleep disorder. It has been reported that many SMS patients have an inverted melatonin secretion pattern (peaking during the daytime) although a small minority have near normal patterns. The goal of this study was to better characterize the intra- and inter-patient variability of melatonin secretion patterns and investigate a potential relationship with sleep behavior in SMS patients.

Methods

In this observational study, sleep behaviors of patients (N=8, 1 female, ages: 7 - 35) with SMS were characterized through caretaker surveys. On 3 separate occasions, patients had hourly serum melatonin levels sampled for 36 hours. From these data, peak serum melatonin concentration and time of peak concentration were determined. Inter- and intra-patient variability was characterized by zero lag correlation of the melatonin concentration timeseries across and within patients, respectively. The relationship between peak melatonin concentration, peak time, and sleep latency was analyzed by a generalized linear model, GLM.

Results

Peak melatonin concentrations varied across SMS patients with a range of 3.55pg/ml - 49.65pg/ml (mean 14.18 ± 15.19pg/ml). Time of peak melatonin concentrations ranged from 0400h-2100h (mean 1422 ± 6h). Correlation coefficients characterizing intra-patient variability ranged from -0.0098 to 0.89 (mean 0.55 ± 0.2533). Correlation coefficients characterizing inter-patient variability ranged from -0.75 to 0.79 (mean of 0.18 ± 0.52). Sleep latency ranged from 8.4min - 36.35min (mean of 21.99 ± 9.77 min). GLM analysis demonstrated a significant, positive effect of peak time with sleep latency (p=0.022).

Conclusion

Consistent with previous findings, our study confirms that SMS patients have abnormal circadian rhythms. Our work extends this body of literature by demonstrating a significant degree of inter-patient variability with relatively stable intra-patient variability. Preliminary evidence suggests that the timing of melatonin peak may be related to sleep onset latency.

Support

This work was supported by Vanda Pharmaceuticals Inc.