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Toothed whales (odontocetes) make use of high-frequency sounds to echolocate, differing significantly from their sister group baleen whales (mysticetes), which make use of low-frequency sound for long-distance communication. This divergence in auditory ability has led to considerable speculation as to how hearing functioned in the ancestral archaeocetes, and when the specializations of modern species arose. Numerous studies have attempted to infer auditory capabilities from morphological correlates valid in modern species. Here, we build upon these previous methods with a focus on cochlear structures that have well-understood links to function. We combine this with information on the sound conduction apparatus to chart the evolutionary trajectory of cetacean hearing. Our results suggest an initial move toward low-frequency specialization in early Eocene cetaceans, which coincides with the appearance of new sound conduction pathways. This paved the way for the later movement toward higher-frequency hearing in protocetids; however, the ultra-high- and low-frequency hearing specializations of both modern cetacean clades evolved after their divergence. We use these data to test the hypotheses that evolutionary brain size increases in cetaceans were related to the origin of high-frequency echolocation. We show that no shift in relative brain size coincides with any changes toward high-frequency perception. However, this does not rule out a role for other changes in hearing ability such as some simple forms of echolocation, similar to that suggested for hippopotamuses or bowhead whales, which may have been present in even the earliest cetaceans.
To measure SARS-CoV-2 anti-nucleocapsid (anti-N) antibody seropositivity among healthcare personnel (HCP) without a history of COVID-19 and to identify HCP characteristics associated with seropositivity.
Design:
Prospective cohort study from September 22, 2020, to March 3, 2022.
Setting:
A tertiary care academic medical center.
Participants:
727 HCP without prior positive SARS-CoV-2 PCR testing were enrolled; 559 HCP successfully completed follow-up.
Methods:
At enrollment and follow-up 1–6 months later, HCP underwent SARS-CoV-2 anti-N testing and were surveyed on demographics, employment information, vaccination status, and COVID-19 symptoms and exposures.
Results:
Of 727 HCP enrolled, 27 (3.7%) had a positive SARS-CoV-2 anti-N test at enrollment. Seropositive HCPs were more likely to have a household exposure to COVID-19 in the past 30 days (OR 7.92, 95% CI 2.44–25.73), to have had an illness thought to be COVID-19 (4.31, 1.94–9.57), or to work with COVID-19 patients more than half the time (2.09, 0.94–4.77). Among 559 HCP who followed-up, 52 (9.3%) had a positive SARS-CoV-2 anti-N antibody test result. Seropositivity at follow-up was associated with community/household exposures to COVID-19 within the past 30 days (9.50, 5.02–17.96; 2.90, 1.31–6.44), having an illness thought to be COVID-19 (8.24, 4.44–15.29), and working with COVID-19 patients more than half the time (1.50, 0.80–2.78).
Conclusions:
Among HCP without prior positive SARS-CoV-2 testing, SARS-CoV-2 anti-N seropositivity was comparable to that of the general population and was associated with COVID-19 symptomatology and both occupational and non-occupational exposures to COVID-19.
To determine the prevalence of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) IgG nucleocapsid (N) antibodies among healthcare personnel (HCP) with no prior history of COVID-19 and to identify factors associated with seropositivity.
Design:
Prospective cohort study.
Setting:
An academic, tertiary-care hospital in St. Louis, Missouri.
Participants:
The study included 400 HCP aged ≥18 years who potentially worked with coronavirus disease 2019 (COVID-19) patients and had no known history of COVID-19; 309 of these HCP also completed a follow-up visit 70–160 days after enrollment. Enrollment visits took place between September and December 2020. Follow-up visits took place between December 2020 and April 2021.
Methods:
At each study visit, participants underwent SARS-CoV-2 IgG N-antibody testing using the Abbott SARS-CoV-2 IgG assay and completed a survey providing information about demographics, job characteristics, comorbidities, symptoms, and potential SARS-CoV-2 exposures.
Results:
Participants were predominately women (64%) and white (79%), with median age of 34.5 years (interquartile range [IQR], 30–45). Among the 400 HCP, 18 (4.5%) were seropositive for IgG N-antibodies at enrollment. Also, 34 (11.0%) of 309 were seropositive at follow-up. HCP who reported having a household contact with COVID-19 had greater likelihood of seropositivity at both enrollment and at follow-up.
Conclusions:
In this cohort of HCP during the first wave of the COVID-19 pandemic, ∼1 in 20 had serological evidence of prior, undocumented SARS-CoV-2 infection at enrollment. Having a household contact with COVID-19 was associated with seropositivity.
In this prospective, longitudinal study, we examined the risk factors for severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among a cohort of chronic hemodialysis (HD) patients and healthcare personnel (HCPs) over a 6-month period. The risk of SARS-CoV-2 infection among HD patients and HCPs was consistently associated with a household member having SARS-CoV-2 infection.
To identify characteristics associated with positive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) polymerase chain reaction (PCR) tests in healthcare personnel.
Design:
Retrospective cohort study.
Setting:
A multihospital healthcare system.
Participants:
Employees who reported SARS-CoV-2 exposures and/or symptoms of coronavirus disease 2019 (COVID-19) between March 30, 2020, and September 20, 2020, and were subsequently referred for SARS-CoV-2 PCR testing.
Methods:
Data from exposure and/or symptom reports were linked to the corresponding SARS-CoV-2 PCR test result. Employee demographic characteristics, occupational characteristics, SARS-CoV-2 exposure history, and symptoms were evaluated as potential risk factors for having a positive SARS-CoV-2 PCR test.
Results:
Among 6,289 employees who received SARS-CoV-2 PCR testing, 873 (14%) had a positive test. Independent risk factors for a positive PCR included: working in a patient care area (relative risk [RR], 1.82; 95% confidence interval [CI], 1.37–2.40), having a known SARS-CoV-2 exposure (RR, 1.20; 95% CI, 1.04–1.37), reporting a community versus an occupational exposure (RR, 1.87; 95% CI, 1.49–2.34), and having an infected household contact (RR, 2.47; 95% CI, 2.11–2.89). Nearly all HCP (99%) reported symptoms. Symptoms associated with a positive PCR in a multivariable analysis included loss of sense of smell (RR, 2.60; 95% CI, 2.09–3.24) or taste (RR, 1.75; 95% CI, 1.40–2.20), cough (RR, 1.95; 95% CI, 1.40–2.20), fever, and muscle aches.
Conclusions:
In this cohort of >6,000 healthcare system and academic medical center employees early in the pandemic, community exposures, and particularly household exposures, were associated with greater risk of SARS-CoV-2 infection than occupational exposures. This work highlights the importance of COVID-19 prevention in the community and in healthcare settings to prevent COVID-19.
In a prospective cohort of healthcare personnel (HCP), we measured severe acute respiratory syndrome coronavirus virus 2 (SARS-CoV-2) nucleocapsid IgG antibodies after SARS-CoV-2 infection. Among 79 HCP, 68 (86%) were seropositive 14–28 days after their positive PCR test, and 54 (77%) of 70 were seropositive at the 70–180-day follow-up. Many seropositive HCP (95%) experienced an antibody decline by the second visit.
Prophylactic antibiotics are commonly prescribed at discharge for mastectomy, despite guidelines recommending against this practice. We investigated factors associated with postdischarge prophylactic antibiotic use after mastectomy with and without immediate reconstruction and the impact on surgical-site infection (SSI).
Study design:
We studied a cohort of women aged 18–64 years undergoing mastectomy between January 1, 2010, and June 30, 2015, using the MarketScan commercial database. Patients with nonsurgical perioperative infections were excluded. Postdischarge oral antibiotics were identified from outpatient drug claims. SSI was defined using International Classification of Diseases, Ninth Edition, Clinical Modification (ICD-9-CM) diagnosis codes. Generalized linear models were used to determine factors associated with postdischarge prophylactic antibiotic use and SSI.
Results:
The cohort included 38,793 procedures; 24,818 (64%) with immediate reconstruction. Prophylactic antibiotics were prescribed after discharge after 2,688 mastectomy-only procedures (19.2%) and 17,807 mastectomies with immediate reconstruction (71.8%). The 90-day incidence of SSI was 3.5% after mastectomy only and 8.8% after mastectomy with immediate reconstruction. Antibiotics with anti–methicillin-sensitive Staphylococcus aureus (MSSA) activity were associated with decreased SSI risk after mastectomy only (adjusted relative risk [aRR], 0.74; 95% confidence interval [CI], 0.55–0.99) and mastectomy with immediate reconstruction (aRR, 0.80; 95% CI, 0.73–0.88), respectively. The numbers needed to treat to prevent 1 additional SSI were 107 and 48, respectively.
Conclusions:
Postdischarge prophylactic antibiotics were common after mastectomy. Anti-MSSA antibiotics were associated with decreased risk of SSI for patients who had mastectomy only and those who had mastectomy with immediate reconstruction. The high numbers needed to treat suggest that potential benefits of postdischarge antibiotics should be weighed against potential harms associated with antibiotic overuse.
Young people may have elevated risk for poorer mental health during the coronavirus disease 2019 (COVID-19) pandemic, yet longitudinal studies documenting this impact are lacking. This study assessed changes in mental health and help-seeking since COVID-19 restrictions in young Australians, including gender differences.
Methods
Data were drawn from a recent subsample (n = 443; 60% female; Mage = 22.0) of a prospective cohort originally recruited in secondary school to complete annual surveys. The subsample completed an additional COVID-19 survey during COVID-19 restrictions (May–June 2020), which was compared to responses from their latest annual survey (August 2019–March 2020). Mixed effect models with time and gender as the primary predictors were conducted for: (i) scores on the Patient Health Questionnaire Depression 9-item (PHQ-9) and Generalised Anxiety Disorder 7-item (GAD-7) modules assessed before and during COVID-19 restrictions, and (ii) self-reported help-seeking from a health professional in February 2020, and the month preceding May–June 2020.
Results
Mean symptom scores increased from before to during COVID-19 restrictions on the PHQ-9 (coefficient: 1.29; 95% CI 0.72–1.86) and GAD-7 (0.78; 95% CI 0.26–1.31), but there was no increase in help-seeking over time (odds ratio 0.50; 95% CI 0.19–1.32). There was no evidence of differential changes by gender.
Conclusions
This study found increases in depression and anxiety symptoms but not greater help-seeking among young Australian adults during the first wave of the pandemic. Increasing availability and awareness of accessible treatment options and psychoeducation is critical, as well as further research into risk and protective factors to help target treatment to this vulnerable age group.
This is the first report on the association between trauma exposure and depression from the Advancing Understanding of RecOvery afteR traumA(AURORA) multisite longitudinal study of adverse post-traumatic neuropsychiatric sequelae (APNS) among participants seeking emergency department (ED) treatment in the aftermath of a traumatic life experience.
Methods
We focus on participants presenting at EDs after a motor vehicle collision (MVC), which characterizes most AURORA participants, and examine associations of participant socio-demographics and MVC characteristics with 8-week depression as mediated through peritraumatic symptoms and 2-week depression.
Results
Eight-week depression prevalence was relatively high (27.8%) and associated with several MVC characteristics (being passenger v. driver; injuries to other people). Peritraumatic distress was associated with 2-week but not 8-week depression. Most of these associations held when controlling for peritraumatic symptoms and, to a lesser degree, depressive symptoms at 2-weeks post-trauma.
Conclusions
These observations, coupled with substantial variation in the relative strength of the mediating pathways across predictors, raises the possibility of diverse and potentially complex underlying biological and psychological processes that remain to be elucidated in more in-depth analyses of the rich and evolving AURORA database to find new targets for intervention and new tools for risk-based stratification following trauma exposure.
We performed a mixed-methods study to evaluate antimicrobial stewardship program (ASP) uptake and to assess variability of program implementation in Missouri hospitals. Despite increasing uptake of ASPs in Missouri, there is wide variability in both the scope and sophistication of these programs.
Akathisia, dystonia, dyskinesia and parkinsonism, the four main categories of neuroleptic-induced extrapyramidal syndromes (EPS), represent major disadvantages in antipsychotic therapy. In vulnerable patients, acute EPS may progress into potentially irreversible forms such as tardive dystonia and tardive dyskinesia. In the psychiatric clinic, these EPS are often insufficiently recognised or permitted to exist without treatment. In order to ensure a better EPS diagnosis, a simple examination procedure is described. EPS rating scales may serve as an aid in this process. Guidelines are given to prevent and treat EPS. Thus, EPS are best prevented by a course of neuroleptic medication involving as little antidopaminergic D2 effect as possible, including the use of the lowest effective dose (sometimes obtained by addition of a benzodiazepine or carbamazepine) and with antipsychotic drugs which produce low D2 receptor blockade. Treating EPS also consists of using the lowest effective dose and antipsychotics with a low D2 dopamine receptor occupancy. At present, clozapine is the only drug that produces antipsychotic benefits at doses that cause far less D2 receptor antagonism in the basal ganglia of the brain than that seen with standard neuroleptics; however, newer drugs, such as olanzepine, seroquel and sertindole, are on the way.
Parasitism can affect every aspect of wildlife ecology, from predator avoidance and competition for food to migrations and reproduction. In the wild, these ecological effects can have implications for host fitness and parasite dynamics. In contrast, domestic environments are typically characterised by high host densities, low host diversity, and veterinary interventions, and are not subject to processes like predation, competition, and migration. When wild and domesticated hosts interact via shared parasite populations, understanding and predicting the outcomes of parasite ecology and evolution for wildlife conservation and sustainable farming can be a challenge. We describe the ecology and evolution of ectoparasitic sea lice that are shared by farmed and wild salmon and the insights that experiments, fieldwork, and mathematical modelling have generated for theory and applied problems of host–parasite interactions over the course of a long-term study in Pacific Canada. The salmon–sea lice host–parasite system provides a rich case study to examine the ecological context of host–parasite interactions and to shed light on the principal challenges of parasite management for wildlife health and conservation.
Despite children’s unique vulnerability, clinical guidance and resources are lacking around the use of radiation medical countermeasures (MCMs) available commercially and in the Strategic National Stockpile to support immediate dispensing to pediatric populations. To better understand the current capabilities and shortfalls, a literature review and gap analysis were performed.
Methods
A comprehensive review of the medical literature, Food and Drug Administration (FDA)-approved labeling, FDA summary reviews, medical references, and educational resources related to pediatric radiation MCMs was performed from May 2016 to February 2017.
Results
Fifteen gaps related to the use of radiation MCMs in children were identified. The need to address these gaps was prioritized based upon the potential to decrease morbidity and mortality, improve clinical management, strengthen caregiver education, and increase the relevant evidence base.
Conclusions
Key gaps exist in information to support the safe and successful use of MCMs in children during radiation emergencies; failure to address these gaps could have negative consequences for families and communities. There is a clear need for pediatric-specific guidance to ensure clinicians can appropriately identify, triage, and treat children who have been exposed to radiation, and for resources to ensure accurate communication about the safety and utility of radiation MCMs for children. (Disaster Med Public Health Preparedness. 2019;13:639-646)
Westgate Oxford is a commercial redevelopment of a large shopping complex in the center of Oxford, with clients Westgate Oxford Alliance and principal contractor Laing O'Rourke. The excavations, carried out by Oxford Archaeology, between 2014 and 2016, were required as part of UK Planning Guidelines and were the largest ever undertaken in the city and principally focused on a large medieval suburban friary. The project won Best Archaeological Project 2016 at the prestigious national British Archaeological Awards, and the outreach program, which included an evolving pop-up museum, was a significant contributing factor. This essay will demonstrate how to set up a pop-up museum in eight steps. The essay will look at how to work with different partners of a project. It will discuss choosing a story to tell and how to deal with a changing narrative on an archaeological site in “real time.” It will show how the Pop Up museum became the principal location for dissemination for the Westgate Oxford project. The essay will conclude with how to keep the story alive and plans for the future of the Westgate Oxford Pop Up Museum.
Preparing and responding to the needs of children during public health emergencies continues to be challenging. The purpose of this study was to assess the usefulness of a tabletop exercise in initiating pediatric preparedness strategies and assessing the impact of the exercise on participants’ understanding of and confidence in their roles during pediatric public health emergencies.
Methods
A tabletop exercise was developed to simulate a public health emergency scenario involving smallpox in a child, with subsequent spread to multiple states. During the exercise, participants discussed and developed communication, collaboration, and medical countermeasure strategies to enhance pediatric public health preparedness. Exercise evaluation was designed to assess participants’ knowledge gained and level of confidence surrounding pediatric public health emergencies.
Results
In total, 22 participants identified over 100 communication and collaboration strategies to promote pediatric public health preparedness during the exercise and found that the most beneficial aspect during the exercise was the partnership between pediatricians and public health officials. Participants’ knowledge and level of confidence surrounding a pediatric public health emergency increased after the exercise.
Conclusion
The tabletop exercise was effective in identifying strategies to improve pediatric public health preparedness as well as enhancing participants’ knowledge and confidence surrounding a potential pediatric public health emergency. (Disaster Med Public Health Preparedness. 2018;12:582–586)
The generation of internal gravity waves by a vertically oscillating cylinder that is tilted to the horizontal in a stratified Boussinesq fluid of constant buoyancy frequency, $N$, is investigated. This variant of the widely studied horizontal configuration – where a cylinder aligned with a plane of constant gravitational potential induces four wave beams that emanate from the cylinder, forming a cross pattern known as the ‘St. Andrew’s Cross’ – brings out certain unique features of radiated internal waves from a line source tilted to the horizontal. Specifically, simple kinematic considerations reveal that for a cylinder inclined by a given angle $\unicode[STIX]{x1D719}$ to the horizontal, there is a cutoff frequency, $N\sin \unicode[STIX]{x1D719}$, below which there is no longer a radiated wave field. Furthermore, three-dimensional effects due to the finite length of the cylinder, which are minor in the horizontal configuration, become a significant factor and eventually dominate the wave field as the cutoff frequency is approached; these results are confirmed by supporting laboratory experiments. The kinematic analysis, moreover, suggests a resonance phenomenon near the cutoff frequency as the group-velocity component perpendicular to the cylinder direction vanishes at cutoff; as a result, energy cannot be easily radiated away from the source, and nonlinear and viscous effects are likely to come into play. This scenario is examined by adapting the model for three-dimensional wave beams developed in Kataoka & Akylas (J. Fluid Mech., vol. 769, 2015, pp. 621–634) to the near-resonant wave field due to a tilted line source of large but finite length. According to this model, the combination of three-dimensional, nonlinear and viscous effects near cutoff triggers transfer of energy, through the action of Reynolds stresses, to a circulating horizontal mean flow. Experimental evidence of such an induced mean flow near cutoff is also presented.
Objectives: The Priorities and Evaluation Committee (PEC) funding recommendations for new cancer drugs in British Columbia, Canada have been based on both clinical and economic evidence. The British Columbia Ministry of Health makes funding decisions. We assessed the association between cost-effectiveness of cancer drugs considered from 1998 to 2008 and the subsequent funding decisions.
Methods: All proposals submitted to the PEC between 1998 and 2008 were reviewed, and the association between cost-effectiveness and funding decisions was examined by (i) using logistic regression to test the hypothesis that interventions with higher incremental cost-effectiveness ratios (ICERs) have a lower probability of receiving a positive funding decision and (ii) using parametric and nonparametric tests to determine if a statistically significant difference exists between the mean cost-effectiveness of funded versus not funded proposals. A sub-analysis was conducted to determine if the findings varied across different outcome measures.
Results: Of the 149 proposals reviewed, 78 reported cost-effectiveness using various outcome measures. In the proposals that used life-years gained as the outcome (n = 22), a statistically significant difference of nearly $115,000 was observed between the mean ICERs for funded proposals ($42,006) and for unfunded proposals ($156,967). An odds ratio indicating higher ICERs have a lower probability of being funded was also found to be statistically significant (p < .05).
Conclusions: Economic evidence appears to play a role in British Columbia cancer funding decisions from 1998 to 2008; other decision-making criteria may also have an important role in recommendations and subsequent funding decisions.