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As COVID-19 spread rapidly during the early months of the pandemic, many communities around the globe anxiously waited for a vaccine. At the start of the pandemic, it was widely believed that Africa would be a significant source of infection, and thus, vaccinating African communities became a primary goal among local and global health authorities. However, when the COVID-19 vaccine became available in March 2021 in Sierra Leone, many people viewed it with scepticism and hesitation. While much literature has focused on access and distribution-related challenges for vaccination in the region, a growing number of studies discuss vaccine hesitancy as driving low vaccine uptake. Shifting attention to understanding the determinants of vaccine hesitancy remains fundamental to increasing vaccination rates, as negative vaccine perceptions tend to delay or prevent vaccination. This study sought to do this by assessing, through semi-structured qualitative interviews, vaccine-related attitudes and experiences of residents of Sierra Leone’s Kono District. In contrast to studies that utilise “knowledge-deficit” models of belief, however, this study drew upon the vaccine anxieties framework (Leach and Fairhead, 2007), which views vaccines as being imbued with personal, historical, and political meaning. Findings suggest that important bodily, social, and political factors, including fear of side effects, the spread of misinformation prompted by poor messaging strategies, and distrust of government and international actors, influenced people’s COVID-19 vaccine attitudes and behaviours. It is hoped that the study’s findings will inform future policies and interventions related to vaccine uptake in Africa and globally.
A wake model is pursued for potential flow past a submerged, finite-length plate that is perpendicular to a uniform, horizontal stream bounded above by a free surface. The effects of gravity are included along the free surface. The approach is to adopt an open-wake model such that the wake boundaries become parallel to the undisturbed stream at some (unknown) point downstream. Boundary integral equations are formed and then discretised along the wake boundaries and free surface in order to obtain a solution numerically. In terms of the dependency of the solution on various parameters, the problem will be formulated in two ways. First, for a given Froude number and ratio of the length of the vertical plate to the draft (the depth of the bottom of the vertical plate relative to the undisturbed free surface), the effect of the wake underpressure coefficient on the size of the wake will be considered. Then, the problem will be discussed where we instead (more naturally) fix the Froude number, draft and length of the vertical, submerged plate. The dependencies of the solution on these parameters will be analysed regarding the effects on several factors, including the size of the wake, the relative lengths of the upper and lower wake boundaries, and the resulting wake underpressure coefficient.
A vermiculite (Libby, Montana) sample obtained from the Zonolite company contained mostly coarse-grained separates with only 8–7 per cent clay. The 2–50 μm fraction was used for particle-size reduction studies by wet and dry grinding, and size-fractionated into < 2, 2–5, 5–20 and 20–50 μ sizes. About 18 per cent of the sample was attrited to clay after 64 hr of wet grinding, but as much as 59 per cent of the sample was attrited to clay after only 10 min of dry grinding. There was no evidence of damage to the crystal structure of derived clays or silts except for the 20–50 μm fraction from dry grinding.
The observed CEC values of all the fractions decreased as grinding progressed, except for the 2–5 μm fraction from wet grinding where the CEC increased. The decrease in CEC was attributed to an accumulation of biotite, either as a discrete mineral and/or a mixed-layer assemblage of biotite and vermiculite attrited to the clay fraction. In contrast, the fraction showing an increase in CEC was due to an increased concentration of higher charge-density (CEC) vermiculite. Biotite-free CEC data for vermiculite suggested that, in general, the coarser vermiculite separates had a higher CEC than the finer ones.
The susceptibility of minerals in the Libby vermiculite to cleavage by grinding was: vermiculite > hydrobiotite > biotite.
Knowledge of sex differences in risk factors for posttraumatic stress disorder (PTSD) can contribute to the development of refined preventive interventions. Therefore, the aim of this study was to examine if women and men differ in their vulnerability to risk factors for PTSD.
Methods
As part of the longitudinal AURORA study, 2924 patients seeking emergency department (ED) treatment in the acute aftermath of trauma provided self-report assessments of pre- peri- and post-traumatic risk factors, as well as 3-month PTSD severity. We systematically examined sex-dependent effects of 16 risk factors that have previously been hypothesized to show different associations with PTSD severity in women and men.
Results
Women reported higher PTSD severity at 3-months post-trauma. Z-score comparisons indicated that for five of the 16 examined risk factors the association with 3-month PTSD severity was stronger in men than in women. In multivariable models, interaction effects with sex were observed for pre-traumatic anxiety symptoms, and acute dissociative symptoms; both showed stronger associations with PTSD in men than in women. Subgroup analyses suggested trauma type-conditional effects.
Conclusions
Our findings indicate mechanisms to which men might be particularly vulnerable, demonstrating that known PTSD risk factors might behave differently in women and men. Analyses did not identify any risk factors to which women were more vulnerable than men, pointing toward further mechanisms to explain women's higher PTSD risk. Our study illustrates the need for a more systematic examination of sex differences in contributors to PTSD severity after trauma, which may inform refined preventive interventions.
When COVID-19 reached Sierra Leone, the government responded by implementing strict containment measures. While the effectiveness of such actions has been debated, the socioeconomic and political implications were undeniable. This qualitative study reveals that people suffered tremendously from economic insecurity, strains on social relationships, and civil rights violations, prompting many to perceive the COVID-19 pandemic as worse than the 2014–15 Ebola epidemic. These hardships have driven distrust of the government, which threatens continuing mitigation efforts. Using a feminist global health security frame, which recenters the protection of vulnerable individuals in relation to the state, we call for more contextually-relevant, civil society-informed pandemic responses.
Several hypotheses may explain the association between substance use, posttraumatic stress disorder (PTSD), and depression. However, few studies have utilized a large multisite dataset to understand this complex relationship. Our study assessed the relationship between alcohol and cannabis use trajectories and PTSD and depression symptoms across 3 months in recently trauma-exposed civilians.
Methods
In total, 1618 (1037 female) participants provided self-report data on past 30-day alcohol and cannabis use and PTSD and depression symptoms during their emergency department (baseline) visit. We reassessed participant's substance use and clinical symptoms 2, 8, and 12 weeks posttrauma. Latent class mixture modeling determined alcohol and cannabis use trajectories in the sample. Changes in PTSD and depression symptoms were assessed across alcohol and cannabis use trajectories via a mixed-model repeated-measures analysis of variance.
Results
Three trajectory classes (low, high, increasing use) provided the best model fit for alcohol and cannabis use. The low alcohol use class exhibited lower PTSD symptoms at baseline than the high use class; the low cannabis use class exhibited lower PTSD and depression symptoms at baseline than the high and increasing use classes; these symptoms greatly increased at week 8 and declined at week 12. Participants who already use alcohol and cannabis exhibited greater PTSD and depression symptoms at baseline that increased at week 8 with a decrease in symptoms at week 12.
Conclusions
Our findings suggest that alcohol and cannabis use trajectories are associated with the intensity of posttrauma psychopathology. These findings could potentially inform the timing of therapeutic strategies.
Current psychological trauma-focused interventions have left a gap for individuals who may not be ready for trauma-focused treatment and/or who present with other forms of clinically significant distress, such as subthreshold post-traumatic stress disorder (PTSD). Emotion regulation is a possible transdiagnostic mechanism of change that may promote and maintain some of the varied mental health problems related to trauma exposure.
Aims:
This study examines the feasibility and initial impact of two brief emotion regulation skill trainings targeting different processes hypothesized to reduce trauma-related problems, compared with an active control.
Method:
Subjects (n = 156) were randomized to receive one of three brief internet-based trainings: (1) skill training on accepting emotions, (2) skill training on changing emotions, or (3) stress psychoeducation (control). Participants completed measures of emotion regulation, mindfulness, and affect intensity 24 hours pre- and immediately post-training.
Results:
Results suggested that a brief internet-based skills training programme was feasible and acceptable, with 91.9% completing the training programme to which they were randomized. Results showed that participants in all conditions demonstrated significant decreases in emotion regulation problems over time; yet these improvements did not vary by condition. Participants in the Change condition with higher PTSD symptoms were significantly more likely to have greater increases in positive affect compared with those with lower PTSD symptoms.
Conclusions:
Although the three conditions did not show different outcomes, all three brief internet-delivered trainings were feasible. Results provide direction for future studies to evaluate the delivery of emotion regulation skills in individuals with trauma-related distress.
Childhood adversities (CAs) predict heightened risks of posttraumatic stress disorder (PTSD) and major depressive episode (MDE) among people exposed to adult traumatic events. Identifying which CAs put individuals at greatest risk for these adverse posttraumatic neuropsychiatric sequelae (APNS) is important for targeting prevention interventions.
Methods
Data came from n = 999 patients ages 18–75 presenting to 29 U.S. emergency departments after a motor vehicle collision (MVC) and followed for 3 months, the amount of time traditionally used to define chronic PTSD, in the Advancing Understanding of Recovery After Trauma (AURORA) study. Six CA types were self-reported at baseline: physical abuse, sexual abuse, emotional abuse, physical neglect, emotional neglect and bullying. Both dichotomous measures of ever experiencing each CA type and numeric measures of exposure frequency were included in the analysis. Risk ratios (RRs) of these CA measures as well as complex interactions among these measures were examined as predictors of APNS 3 months post-MVC. APNS was defined as meeting self-reported criteria for either PTSD based on the PTSD Checklist for DSM-5 and/or MDE based on the PROMIS Depression Short-Form 8b. We controlled for pre-MVC lifetime histories of PTSD and MDE. We also examined mediating effects through peritraumatic symptoms assessed in the emergency department and PTSD and MDE assessed in 2-week and 8-week follow-up surveys. Analyses were carried out with robust Poisson regression models.
Results
Most participants (90.9%) reported at least rarely having experienced some CA. Ever experiencing each CA other than emotional neglect was univariably associated with 3-month APNS (RRs = 1.31–1.60). Each CA frequency was also univariably associated with 3-month APNS (RRs = 1.65–2.45). In multivariable models, joint associations of CAs with 3-month APNS were additive, with frequency of emotional abuse (RR = 2.03; 95% CI = 1.43–2.87) and bullying (RR = 1.44; 95% CI = 0.99–2.10) being the strongest predictors. Control variable analyses found that these associations were largely explained by pre-MVC histories of PTSD and MDE.
Conclusions
Although individuals who experience frequent emotional abuse and bullying in childhood have a heightened risk of experiencing APNS after an adult MVC, these associations are largely mediated by prior histories of PTSD and MDE.
Many works have considered two-dimensional free-surface flow over the edge of a plate, forming a waterfall, and with uniform horizontal flow far upstream. The flow is assumed to be steady and irrotational, whilst the fluid is assumed to be inviscid and incompressible. Gravity is also taken into account. In particular, amongst these works, numerical solutions for supercritical flows have been computed, utilising conformal mappings as well as a series truncation and collocation method. We present an extension to this work where a more appropriate expression is taken for the assumed form of the complex velocity. The justification of this lies in the behaviour of the waterfall flow far downstream and the wish to better encapsulate the parabolic nature of such a free-falling jet. New numerical results will be presented, demonstrating the improved shape of the new free-surface profiles. These numerical solutions will also be validated through comparisons with asymptotic solutions, in particular for flows with larger Froude numbers. For flows with Froude numbers closer to 1, we demonstrate that the revised complex velocity ansatz should be employed in place of the asymptotic solution. We present further adjustments to the method that lead to enhanced coefficient decay. The aforementioned adjustments are also applied to supercritical weir flows and similar improvements to the jet shape can be observed.
Racial and ethnic groups in the USA differ in the prevalence of posttraumatic stress disorder (PTSD). Recent research however has not observed consistent racial/ethnic differences in posttraumatic stress in the early aftermath of trauma, suggesting that such differences in chronic PTSD rates may be related to differences in recovery over time.
Methods
As part of the multisite, longitudinal AURORA study, we investigated racial/ethnic differences in PTSD and related outcomes within 3 months after trauma. Participants (n = 930) were recruited from emergency departments across the USA and provided periodic (2 weeks, 8 weeks, and 3 months after trauma) self-report assessments of PTSD, depression, dissociation, anxiety, and resilience. Linear models were completed to investigate racial/ethnic differences in posttraumatic dysfunction with subsequent follow-up models assessing potential effects of prior life stressors.
Results
Racial/ethnic groups did not differ in symptoms over time; however, Black participants showed reduced posttraumatic depression and anxiety symptoms overall compared to Hispanic participants and White participants. Racial/ethnic differences were not attenuated after accounting for differences in sociodemographic factors. However, racial/ethnic differences in depression and anxiety were no longer significant after accounting for greater prior trauma exposure and childhood emotional abuse in White participants.
Conclusions
The present findings suggest prior differences in previous trauma exposure partially mediate the observed racial/ethnic differences in posttraumatic depression and anxiety symptoms following a recent trauma. Our findings further demonstrate that racial/ethnic groups show similar rates of symptom recovery over time. Future work utilizing longer time-scale data is needed to elucidate potential racial/ethnic differences in long-term symptom trajectories.
To present our case series and management of Scedosporium apiospermum infections of the middle ear and mastoid, and review the current literature on this rare yet potentially life-threatening condition.
Methods
Medical records of patients treated at the Royal Victorian Eye and Ear Hospital for S apiospermum middle ear and mastoid infections between 2009 and 2019 were reviewed. A literature search was conducted using PubMed, Medline and Cochrane Library databases.
Results
Two patients were identified in our institution: a 62-year-old diabetic woman with otogenic skull base osteomyelitis, and a 12-year-old boy with unilateral chronic suppurative otitis media which developed after tympanostomy tube insertion. The persistence of otalgia and otorrhoea despite prolonged antibiotic treatment characterised these cases. Both patients received voriconazole, and achieved disease resolution without complications. Ten relevant cases were identified after review of the literature. Despite treatment, there were three patient deaths, and four patients with otological or neurological complications.
Conclusion
The presence of a middle ear or mastoid infection refractory to appropriate topical and systemic antibiotics should prompt clinicians to consider a fungal infection. The role of surgical debridement in the treatment of S apiospermum infection of the middle ear and mastoid is equivocal.
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.
Coronavirus disease 2019 (COVID-19) has migrated to regions that were initially spared, and it is likely that different populations are currently at risk for illness. Herein, we present our observations of the change in characteristics and resource use of COVID-19 patients over time in a national system of community hospitals to help inform those managing surge planning, operational management, and future policy decisions.
To determine risk factors for mortality among COVID-19 patients admitted to a system of community hospitals in the United States.
Design:
Retrospective analysis of patient data collected from the routine care of COVID-19 patients.
Setting:
System of >180 acute-care facilities in the United States.
Participants:
All admitted patients with positive identification of COVID-19 and a documented discharge as of May 12, 2020.
Methods:
Determination of demographic characteristics, vital signs at admission, patient comorbidities and recorded discharge disposition in this population to construct a logistic regression estimating the odds of mortality, particular for those patients characterized as not being critically ill at admission.
Results:
In total, 6,180 COVID-19+ patients were identified as of May 12, 2020. Most COVID-19+ patients (4,808, 77.8%) were admitted directly to a medical-surgical unit with no documented critical care or mechanical ventilation within 8 hours of admission. After adjusting for demographic characteristics, comorbidities, and vital signs at admission in this subgroup, the largest driver of the odds of mortality was patient age (OR, 1.07; 95% CI, 1.06–1.08; P < .001). Decreased oxygen saturation at admission was associated with increased odds of mortality (OR, 1.09; 95% CI, 1.06–1.12; P < .001) as was diabetes (OR, 1.57; 95% CI, 1.21–2.03; P < .001).
Conclusions:
The identification of factors observable at admission that are associated with mortality in COVID-19 patients who are initially admitted to non-critical care units may help care providers, hospital epidemiologists, and hospital safety experts better plan for the care of these patients.
Background: Trauma care represents a complex patient journey, requiring multi-disciplinary coordinated care. Team members are human, and as such, how they feel about their colleagues and their work affects performance. The challenge for health service leaders is enabling culture that supports high levels of collaboration, cooperation and coordination across diverse groups. Aim Statement: We aimed to define and set the agenda for improvement of the relational aspects of trauma care at a large tertiary care hospital. Measures & Design: We conducted a mixed-methods collaborative ethnography using the Relational Coordination survey – an established tool to analyze the relational dimensions of multidisciplinary teamwork – participant observation, interviews, and narrative surveys. Findings were presented to clinicians in working groups for further interpretation and to facilitate co-creation of targeted interventions designed to improve team relationships and performance. Evaluation/Results: We engaged a complex multidisciplinary network of ~500 care providers dispersed across seven core interdependent clinical disciplines. Initial findings highlighted the importance of relationships in trauma care and opportunities to improve. Narrative survey and ethnographic findings further highlighted the centrality of a translational simulation program in contributing positively to team culture and relational ties. A range of 16 interventions – focusing on structural, process and relational dimensions – were co-created with participants and are now being implemented and evaluated by various trauma care providers. Discussion/Impact: Through engagement of clinicians spanning organizational boundaries, relational aspects of care can be measured and directly targeted in a collaborative quality improvement process. We encourage health care leaders to consider relationship-based quality improvement strategies, including translational simulation and relational coordination processes, in their efforts to improve care for patients with complex, interdependent journeys.
Characteristics of DSM-IV attention-deficit/hyperactivity disorder (ADHD) in adults can also be found as part of other psychiatric disorders. This study investigated the specificity of adult ADHD features in relation to patients with borderline personality disorder (BPD), a syndrome which shares some of its intrinsic features with ADHD and often co-occurs with ADHD. A group of 20 adult patients selected on the basis of a diagnosis of ADHD and 20 patients selected on the basis of a diagnosis of BPD were assessed by the self-report Attention Deficit Scales for Adults (ADSA). The two groups were matched for age, verbal IQ and gender. Of the nine ADSA scales, seven showed significant inter-group differences, in particular involving attention, organisation and persistence. The ‘Consistency/Long-Term’ scale, which mainly reflects impaired task and goal persistence, was the best discriminator between the groups. Furthermore, ratings on this scale correlated significantly with the error score of a computer-administered task of spatial working memory, the performance of which has been reported to be impaired in patients with ADHD. The results provide further validation for the ADSA scales and support a previous claim that ‘long-term consistencies’, i.e., related to task and goal persistence, is ‘the centrepiece behavioural issue’ for adults with ADHD.
It is possible that findings suggesting a link between prenatal maternal stress (PNMS) and anxiety symptoms in offspring are confounded by postnatal and/or shared mother–child heritability effects. Following exposure to a natural disaster, the Queensland Flood Study investigated the unique and additive effects of various types of disaster-related PNMS (objective hardship, cognitive appraisal, and subjective distress) on childhood anxiety symptomatology (internalizing and/or anxiety symptom measures). Timing of flood exposure during pregnancy and child sex were examined as potential moderators. After controlling for maternal psychosocial factors, greater objective hardship as a result of the floods was significantly associated with greater anxiety symptoms (N = 114) and marginally associated with greater internalizing behaviors (N = 115). Earlier timing of the flood in pregnancy was associated with greater anxiety symptoms. No such associations were found between any PNMS measure and teacher-rated child internalizing behaviors (N = 90). Sex and timing did not moderate associations. Our findings suggest that, in isolation, increased maternal hardship due to exposure to an independent stressor, during pregnancy, may have a programming effect on childhood anxiety symptoms.
This paper presents the results of a laboratory study on the influence of heterotrophic bacteria on dissolution of a silicate mineral (K-feldspar) under a variety of growth conditions. Twenty seven strains of heterotrophic bacteria were isolated from a feldspar-rich soil (Shap, NW England). Liquid and solid minimal aerobic media (C/N-sufficient, K-limited, Fe-limited, N-limited and glucose/NH4Cl only) at 26ºC were used for isolation of the bacteria. The media selected bacterial isolates that were fastgrowing aerobic heterotrophs able to use glucose as the sole source of carbon and energy. The extent of mineral dissolution (in the presence of the isolates) was assessed after 48 h of incubation by measuring the release of Al from the K-feldspar by ICP-AES. More detailed dissolution experiments were carried out with one of the strains, Serratia marcescens, an isolate that was very effective in enhancing feldspar dissolution. The main conclusions of this study are: (1) the degree of enhancement of K-feldspar dissolution varied with bacterial isolate and growth conditions; (2) enhancement of dissolution began during stationary phase growth; (3) the production of chelating compounds (exopolymers, siderophores, pigments) during the stationary phase might be a possible mechanism for bacterially enhanced K-feldspar dissolution; (4) the frequent sub-culturing of isolates can have a significant effect on their physiological characteristics and may possibly influence their capacity to enhance mineral dissolution.
Studies estimating the human health impact of the foodborne disease often include estimates of the number of gastroenteritis hospitalisations. The aims of this study were to examine the degree to which hospital discharge data underreport hospitalisations due to bacterial gastroenteritis and to estimate the frequency of stool sample submission among patients presenting with gastroenteritis. Using linked laboratory and hospital discharge data from a healthcare organisation and its affiliated hospital, we examined the International Classification of Disease (ICD-9-CM) diagnosis codes assigned to hospitalised adults with culture-confirmed Campylobacter, Salmonella, or Escherichia coli O157 infections and determined the frequency of stool sample submission. Among 138 hospitalised patients with culture-confirmed infections, 43% of Campylobacter patients, 56% of Salmonella patients and 35% of E. coli O157 patients had that pathogen-specific code listed on the discharge record. Among patients without their infection listed as a diagnosis, 65% were assigned a nonspecific gastroenteritis code. Submitting a specimen for culture ⩾3 days before discharge was significantly associated with having the pathogen-specific diagnosis listed. Of 6181 patients assigned a nonspecific gastroenteritis code, 69% had submitted a stool sample for bacterial culture. This study can be used to understand differences and adjust for the underreporting and underdiagnosed of Campylobacter, Salmonella and E. coli O157 in hospital discharge and surveillance data, respectively.
Research was conducted in central Georgia to determine the influence of norflurazon on bermudagrass stand and production when applied to newly sprigged bermudagrass and in the spring to dormant bermudagrass. Norflurazon at rates up to 1.12 kg ai/ha on newly sprigged bermudagrass caused moderate chlorosis to the emerging leaves but did not adversely influence stand density or ground cover at 60 and 90 days after treatment (DAT). Norflurazon applied to dormant bermudagrass the spring of 1993 resulted in greater than 50% foliage chlorosis at rates ≥ 1.68 kg/ha. Foliage chlorosis was 94% on bermudagrass treated with 3.36 kg/ha 30 DAT and at spring growth initiation. However, chlorosis level was reduced when bermudagrass began rapid growth. Forage production was not influenced by the early season chlorosis when compared to nontreated areas or areas treated with diuron at 1.12 kg/ha and the weed free check.