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Michael Smets, Royston Greenwood and Mike Lounsbury show the potential of institutional theory for strategy as practice and its acceleration since 2015. As one of the most vital research areas of organization theory, institutional perspectives bring new insights for the understanding of strategic activities and practice. More precisely, it can help understand the linkage between the different levels of strategic activities but also the internal life of institutions. As a result, scholars in the fields of institutional theory and strategy as practice have begun to reach out to each other to broaden and nuance their respective theorizing. They identify natural points of connection between the two literatures and outline a research agenda for future studies at the intersection of institutional theory and strategy as practice.
The mechanisms underlying generalized forms of dissociative (‘psychogenic’) amnesia are poorly understood. One theory suggests that memory retrieval is inhibited via prefrontal control. Findings from cognitive neuroscience offer a candidate mechanism for this proposed retrieval inhibition. By applying predictions based on these experimental findings, we examined the putative role of retrieval suppression in dissociative amnesia.
Methods
We analyzed fMRI data from two previously reported cases of dissociative amnesia. Patients had been shown reminders from forgotten and remembered time periods (colleagues and school friends). We examined the neuroanatomical overlap between regions engaged in the unrecognized compared to the recognized condition, and the regions engaged during retrieval suppression in laboratory-based tasks. Effective connectivity analyses were performed to test the hypothesized modulatory relationship between the right anterior dorsolateral prefrontal cortex (raDLPFC) and the hippocampus. Both patients were scanned again following treatment, and analyses were repeated.
Results
We observed substantial functional alignment between the inhibitory regions engaged during laboratory-based retrieval suppression tasks, and those engaged when patients failed to recognize their current colleagues. This included significant activation in the raDLPFC and right ventrolateral prefrontal cortex, and a corresponding deactivation across autobiographical memory regions (hippocampus, medial PFC). Dynamic causal modeling confirmed the hypothesized modulatory relationship between the raDLPFC and the hippocampus. This pattern was no longer evident following memory recovery in the first patient, but persisted in the second patient who remained amnesic.
Conclusions
Findings are consistent with an inhibitory mechanism driving down activity across core memory regions to prevent the recognition of personally relevant stimuli.
High-cost gene therapies strain the sustainability of healthcare budgets. Despite the potential long-term savings promised by certain gene therapies, realizing these savings faces challenges due to uncertainties regarding the treatment’s durability and a lesser-discussed factor: the true potential for cost offset. Our study aims to assess the cost-offset uncertainty for US Medicaid regarding recently approved gene therapies in hemophilia A and B.
Methods
The analysis used 2018 to 2022 Colorado Department of Health Care Policy & Financing data to determine direct costs of standard of care (factor replacement therapy or emicizumab). Cost-simulation models over five- and ten-year time horizons estimated Colorado Medicaid costs if patients switched to gene therapy (valoctocogene roxaparvovec or etranacogene dezaparvovec) versus maintaining standard of care. Patients were included if aged 18 and over with ICD-10-CM codes D66 (hemophilia A) and D67 (hemophilia B). In the base case, severe hemophilia A was defined as requiring greater than or equal to six yearly factor VIII or emicizumab claims and moderate/severe hemophilia B requiring greater than or equal to four factor IX replacement therapy claims annually.
Results
Annual standard-of-care costs were USD426,000 (SD USD353,000) for hemophilia A and USD546,000 (SD USD542,000) for hemophilia B. Valoctocogene roxaparvovec (hemophilia A) had incremental costs of USD880,000 at five years and −USD481,000 at 10 years. Sensitivity analysis revealed a 23 percent chance of break-even within five years and 48 percent within 10 years. Etranacogene dezaparvovec (hemophilia B) showed incremental costs of USD429,000 at five years and −USD2,490,000 at 10 years. Simulation indicated a 32 percent chance of break-even within five years and 59 percent within 10 years. Varying eligibility (≥4 to ≥15 standard-of-care claims) notably affected break-even; for example, valoctocogene roxaparvovec: 40 percent to 77 percent chance of break-even in 10 years.
Conclusions
Our study highlights significant cost variation in the standard of care of patients eligible for gene therapies, adding to the uncertainty surrounding cost estimation and highlighting the importance of addressing this factor in risk-sharing agreements. The impact of varying eligibility criteria on cost offsets emphasizes the importance of carefully defining eligibility when using real-world data in the context of health technology assessment.
The association between cannabis and psychosis is established, but the role of underlying genetics is unclear. We used data from the EU-GEI case-control study and UK Biobank to examine the independent and combined effect of heavy cannabis use and schizophrenia polygenic risk score (PRS) on risk for psychosis.
Methods
Genome-wide association study summary statistics from the Psychiatric Genomics Consortium and the Genomic Psychiatry Cohort were used to calculate schizophrenia and cannabis use disorder (CUD) PRS for 1098 participants from the EU-GEI study and 143600 from the UK Biobank. Both datasets had information on cannabis use.
Results
In both samples, schizophrenia PRS and cannabis use independently increased risk of psychosis. Schizophrenia PRS was not associated with patterns of cannabis use in the EU-GEI cases or controls or UK Biobank cases. It was associated with lifetime and daily cannabis use among UK Biobank participants without psychosis, but the effect was substantially reduced when CUD PRS was included in the model. In the EU-GEI sample, regular users of high-potency cannabis had the highest odds of being a case independently of schizophrenia PRS (OR daily use high-potency cannabis adjusted for PRS = 5.09, 95% CI 3.08–8.43, p = 3.21 × 10−10). We found no evidence of interaction between schizophrenia PRS and patterns of cannabis use.
Conclusions
Regular use of high-potency cannabis remains a strong predictor of psychotic disorder independently of schizophrenia PRS, which does not seem to be associated with heavy cannabis use. These are important findings at a time of increasing use and potency of cannabis worldwide.
Product architecture decisions are made early in the product development process and have far-reaching effects. Unless anticipated through experience or intuition, many of these effects may not be apparent until much later in the development process, making changes to the architecture costly in time, effort and resources. Many researchers through the years have studied various elements of product architecture and their effects. By using a repeatable process for aggregating statements on the effects of architecture strategies from a selection of the literature on the topic and storing them in a systematic database, this information can then be recalled and presented in the form of a Product Architecture Strategy and Effect (PASE) matrix. PASE matrices allow for the identification, comparison, evaluation, and then selection of the most desirable product architecture strategies before expending resources along a specific development path. This paper introduces the PASE Database and matrix and describes their construction and use in guiding design decisions. This paper also provides metrics for understanding the robustness of this database.
Congress directed the Secretary of Defense (DoD) to conduct a Pilot program to increase the National Disaster Medical System’s (NDMS) surge capacity, capabilities, and interoperability to support patient movement during a large-scale overseas contingency operation.
Methods
The Pilot conducted a mixed methods exploratory study, the Military-Civilian NDMS Interoperability Study (MCNIS), identifying 55 areas of solutions for NDMS innovation that align with interagency stakeholder interests. Priorities were determined via facilitated discussions, refined and validated by all five Pilot sites.
Results
As the DoD provides essential support for the patient movement component within NDMS, the results highlighted areas for improvement between receiving patients at an airfield and moving them to NDMS definitive care partners during a large medical surge event. This includes patient tracking capabilities, transportation processes and patient placement.
Conclusions
In collaboration with the Departments of Health & Human Services, Homeland Security, Transportation, and Veterans Health Administration, the Pilot is addressing these areas for improvement, by executing site-specific projects that will be validated and identified for export across the system. Leaders across the Pilot site healthcare networks are working to enhance patient movement and tracking. Ultimately, the Pilot will deliver dozens of proven solutions to enhance the NDMS’s patient movement capabilities.
Previous research has examined whether voters will punish candidates who engage in sexual harassment in national-level elections, revealing partisanship as a strong predictor of electoral punishment. Using original survey data, we evaluate whether the public supports a broader range of sanctions (e.g. apologies, training, and removal from office) that legislatures can impose upon politicians who perpetrate sexual harassment in Canada’s municipalities, a non-partisan context. In the absence of partisan-based motivated reasoning, we find that women are more likely than men to support the removal from office of a councillor who engages in sexual harassment. Respondents who do not believe that sexism is a problem and are skeptical about claims of gender-based violence are also less likely to support punishment in these cases. These findings have relevance for democratic institutions, revealing that sanctions imposed on politicians who perpetrate sexual harassment can help maintain political accountability and restore public trust.
From early on, infants show a preference for infant-directed speech (IDS) over adult-directed speech (ADS), and exposure to IDS has been correlated with language outcome measures such as vocabulary. The present multi-laboratory study explores this issue by investigating whether there is a link between early preference for IDS and later vocabulary size. Infants’ preference for IDS was tested as part of the ManyBabies 1 project, and follow-up CDI data were collected from a subsample of this dataset at 18 and 24 months. A total of 341 (18 months) and 327 (24 months) infants were tested across 21 laboratories. In neither preregistered analyses with North American and UK English, nor exploratory analyses with a larger sample did we find evidence for a relation between IDS preference and later vocabulary. We discuss implications of this finding in light of recent work suggesting that IDS preference measured in the laboratory has low test-retest reliability.
Background: Presenteeism when ill in healthcare personnel (HCP) can contribute to the spread of respiratory illness among HCP and patients. However, during the COVID-19 pandemic and now, there are substantial challenges preventing HCP from staying home when ill. We examined these challenges using the Systems Engineering Initiative for Patient Safety (SEIPS) framework. Method: As part of a larger anonymous electronic survey between 3/11/2022 and 4/12/2022 at an academic tertiary referral center, in inpatient and ambulatory settings where respondents were asked to describe factors impacting presenteeism when ill, we analyzed free-text responses using the SEIPS categories of tasks, tools/technology, person, organization, and physical environment. Result: 522 comments were received in response to the open-ended survey question asking individuals to describe any factors that would assist them in remaining home and/or help them get tested for COVID-19 when they have symptoms of a respiratory illness; 21 were excluded due to absent or incomplete response. Of the remaining responses (N = 501, Figure 1), 82% were associated with a single SEIPS component such as organization (N = 409), while other responses discussed factors that involved two SEIPS components, in no particular order (N = 92). A majority of the responses (N = 324, 55%) reported organizational barriers, frequently citing a strict sick call-in policy as well as a lack of protected time-off for COVID-19 testing or related absences. The next two most commonly identified components were physical environment (N= 88, 15%) and tasks (N = 72, 12%), mentioning barriers such as far distances to testing centers and prolonged waiting periods for testing Results: The person and tools/technology components were less commonly identified, with a frequency of 9% each. Conclusion: A number of systems level factors were identified that may impact the ability of HCP to stay home when ill. Interventions to help overcome HCP perceived barriers to staying home when experiencing respiratory symptoms should focus on the policies and practices within an organization. Communication from leadership should support staying home with respiratory symptoms by creating plans for coverage and back up consistently across all employee types in direct care.
Background: External comparisons of antimicrobial use (AU) may be more informative if adjusted for encounter characteristics. Optimal methods to define input variables for encounter-level risk-adjustment models of AU are not established. Methods: This retrospective analysis of electronic health record data included 50 US hospitals in 2020-2021. We used NHSN definitions for all antibacterials days of therapy (DOT), including adult and pediatric encounters with at least 1 day present in inpatient locations. We assessed 4 methods to define input variables: 1) diagnosis-related group (DRG) categories by Yu et al., 2) adjudicated Elixhauser comorbidity categories by Goodman et al., 3) all Clinical Classification Software Refined (CCSR) diagnosis and procedure categories, and 4) adjudicated CCSR categories where codes not appropriate for AU risk-adjustment were excluded by expert consensus, requiring review of 867 codes over 4 months to attain consensus. Data were split randomly, stratified by bed size as follows: 1) training dataset including two-thirds of encounters among two-thirds of hospitals; 2) internal testing set including one-third of encounters within training hospitals, and 3) external testing set including the remaining one-third of hospitals. We used a gradient-boosted machine (GBM) tree-based model and two-staged approach to first identify encounters with zero DOT, then estimate DOT among those with >0.5 probability of receiving antibiotics. Accuracy was assessed using mean absolute error (MAE) in testing datasets. Correlation plots compared model estimates and observed DOT among testing datasets. The top 20 most influential variables were defined using modeled variable importance. Results: Our datasets included 629,445 training, 314,971 internal testing, and 419,109 external testing encounters. Demographic data included 41% male, 59% non-Hispanic White, 25% non-Hispanic Black, 9% Hispanic, and 5% pediatric encounters. DRG was missing in 29% of encounters. MAE was lower in pediatrics as compared to adults, and lowest for models incorporating CCSR inputs (Figure 1). Performance in internal and external testing was similar, though Goodman/Elixhauser variable strategies were less accurate in external testing and underestimated long DOT outliers (Figure 2). Agnostic and adjudicated CCSR model estimates were highly correlated; their influential variables lists were similar (Figure 3). Conclusion: Larger numbers of CCSR diagnosis and procedure inputs improved risk-adjustment model accuracy compared with prior strategies. Variable importance and accuracy were similar for agnostic and adjudicated approaches. However, maintaining adjudications by experts would require significant time and potentially introduce personal bias. If findings are confirmed, the need for expert adjudication of input variables should be reconsidered.
Disclosure: Elizabeth Dodds Ashley: Advisor- HealthTrackRx. David J Weber: Consultant on vaccines: Pfizer; DSMB chair: GSK; Consultant on disinfection: BD, GAMA, PDI, Germitec
With the rise of online references, podcasts, webinars, self-test tools, and social media, it is worthwhile to understand whether textbooks continue to provide value in medical education, and to assess the capacity they serve during fellowship training.
Methods:
A prospective mixed-methods study based on surveys that were disseminated to seven paediatric cardiology fellowship programmes around the world. Participants were asked to read an assigned chapter of Anderson’s Pediatric Cardiology 4th Edition textbook, followed by the completion of the survey. Open-ended questions included theming and grouping responses as appropriate.
Results:
The survey was completed by 36 participants. When asked about the content, organisation, and utility of the chapter, responses were generally positive, at greater than 89%. The chapters, overall, were rated relatively easy to read, scoring at 6.91, with standard deviations plus or minus 1.72, on a scale from 1 to 10, with higher values meaning better results. When asked to rank their preferences in where they obtain educational content, textbooks were ranked the second highest, with in-person teaching ranking first. Several themes were identified including the limitations of the use of textbook use, their value, and ways to enhance learning from their reading. There was also a near-unanimous desire for more time to self-learn and read during fellowship.
Conclusions:
Textbooks are still highly valued by trainees. Many opportunities exist, nonetheless, to improve how they can be organised to deliver information optimally. Future efforts should look towards making them more accessible, and to include more resources for asynchronous learning.
Substance use disorders among juveniles are a major public health concern and are often intertwined with other psychosocial risk factors including antisocial behavior. Identifying etiological risks and mechanisms promoting substance use disorders remains a high priority for informing more focused interventions in high-risk populations. The present study examined brain gray matter structure in relation to substance use severity among n = 152 high-risk, incarcerated boys (aged 14–20). Substance use severity was positively associated with gray matter volume across several frontal/striatal brain regions including amygdala, pallidum, putamen, insula, and orbitofrontal cortex. Effects were apparent when using voxel-based-morphometric analysis, as well as in whole-brain, data-driven, network-based approaches (source-based morphometry). These findings support the hypothesis that elevated gray matter volume in striatal reward circuits may be an endogenous marker for vulnerability to severe substance use behaviors among youth.
OBJECTIVES/GOALS: High serum copper (Cu) levels have previously been described in bariatric patients. The kidneys are a target organ for Cu toxic insult but the role of Cu on kidney function (eGFR) is uncertain. This study examines the association between Cu and eGFR in a bariatric population in Southeast Louisiana. METHODS/STUDY POPULATION: Seven hundred fifty patients will be recruited from the Bariatric Center of the University Medical Center in New Orleans. Inclusion criteria include: age ≥ 18 years, clinic visit between June 1, 2018 – May 31st 2024, and having a serum Cu test result. Covariables such as inflammatory markers and hormonal contraception use will be assessed as potential confounders. Blood pressure will be assessed as a potential effect modifier. Data will be obtained from electronic medical records. Two cohorts will be assembled, a pre-surgery cross-sectional cohort and another followed post-surgery. Separate models will be developed stratified by race-ethnicity. RESULTS/ANTICIPATED RESULTS: In a pilot study of bariatric patients 26% had elevated (>155 mcg/dl) serum Cu and pronounced racial differences were noted. Characteristics consisted of a mean BMI of approximately 50 kg/m2; 91% were female and 69% were Black. Black patients had approximately double the prevalence (OR 1.98; 95% CI: 1.15, 3.4) compared to white patients. Due to the dual nature of the kidneys’ involvement in metabolism via excretion and being the target organ for toxic insult, racial differences in exposure, coupled with the disproportionate rates of chronic kidney disease in Black adults, may be an explanation for the association between elevated Cu levels and eGFR in Black adults in this study. DISCUSSION/SIGNIFICANCE: Results from this study will provide insight into the prevalence of Cu and its association with kidney function in a bariatric population. Chronic kidney disease or other forms of renal impairment may result in the need for more conservative guidelines for dietary copper in bariatric medicine.
Dynamical and thermodynamic properties of water at room temperature in Ca- and hexade-cyltrimethylammonium- (HDTMA) exchanged bentonite were determined for 4 different water contents (~0.03–0.55 g water g-1 clay). Incoherent quasi-elastic neutron scattering (QENS) was used to measure the translational and rotational mobility of water in the clays, while chilled mirror dewpoint psychrometry measured water activity of the samples, differential scanning calorimetry (DSC) provided information about the temperature of dehydration and X-ray diffraction (XRD) quantified layer spacings for the clays. The neutron scattering data were fit to a jump diffusion model that yielded mean jump lengths, jump diffusion residence times and rotational relaxation times for water in the clays. Mean jump lengths were quite similar for the 2 different cation saturations at equivalent water contents, and decreased with increasing water content. The fitted jump lengths ranged from 0.27–0.5 nm and were 2–4 times larger than that found for bulk water (0.13 nm). Jump diffusion residence times were 3–30 times longer than that for bulk water (1.2 ps) and also decreased with increasing water content. The residence times were somewhat shorter for HDTMA-clay as compared with Ca-clay at equivalent water contents. Rotational motion was less strongly influenced than translational motion by the presence of the clay surface. The energy state of water in the 2 cation saturations were quite different; dehydration temperatures for the HDTMA-clay were approximately 30 °C lower than the Ca-clay at equal water contents, while water activities, as P/P0, were up to 0.6 units higher. A linear relationship was found between water activity and the translational diffusion coefficient, although at the highest water content, the diffusion coefficient of water for the HDTMA-clay was approximately 30% higher than that measured for bulk water.
To determine whether removal of default duration, embedded in electronic prescription (e-script), influenced antibiotic days of therapy.
Design:
Interrupted time-series analysis.
Setting:
The study was conducted across 2 community hospitals, 1 academic hospital, 3 emergency departments, and 86 ambulatory clinics.
Patients:
Adults prescribed a fluoroquinolone with a duration <31 days.
Interventions:
Removal of standard 10-day fluoroquinolone default duration and addition of literature-based duration guidance in the order entry on December 19, 2017. The study period included data for 12 months before and after the intervention.
Results:
The study included 35,609 fluoroquinolone e-scripts from the preintervention period and 31,303 fluoroquinolone e-scripts from the postintervention period, accounting for 520,388 cumulative fluoroquinolone DOT. Mean durations before and after the intervention were 7.8 (SD, 4.3) and 7.7 (SD, 4.5), a nonsignificant change. E-scripts with a 10-day duration decreased prior to and after the default removal. The inpatient setting showed a significant 8% drop in 10-day e-scripts after default removal and a reduced median duration by 1 day; 10-day scripts declined nonsignificantly in ED and ambulatory settings. In the ambulatory settings, both 7- and 14-day e-script durations increased after default removal.
Conclusion:
Removal of default 10-day antibiotic durations did not affect overall mean duration but did shift patterns in prescribing, depending on practice setting. Stewardship interventions must be studied in the context of practice setting. Ambulatory stewardship efforts separate from inpatient programs are needed because interventions cannot be assumed to have similar effects.
Incidence of first-episode psychosis (FEP) varies substantially across geographic regions. Phenotypes of subclinical psychosis (SP), such as psychotic-like experiences (PLEs) and schizotypy, present several similarities with psychosis. We aimed to examine whether SP measures varied across different sites and whether this variation was comparable with FEP incidence within the same areas. We further examined contribution of environmental and genetic factors to SP.
Methods
We used data from 1497 controls recruited in 16 different sites across 6 countries. Factor scores for several psychopathological dimensions of schizotypy and PLEs were obtained using multidimensional item response theory models. Variation of these scores was assessed using multi-level regression analysis to estimate individual and between-sites variance adjusting for age, sex, education, migrant, employment and relational status, childhood adversity, and cannabis use. In the final model we added local FEP incidence as a second-level variable. Association with genetic liability was examined separately.
Results
Schizotypy showed a large between-sites variation with up to 15% of variance attributable to site-level characteristics. Adding local FEP incidence to the model considerably reduced the between-sites unexplained schizotypy variance. PLEs did not show as much variation. Overall, SP was associated with younger age, migrant, unmarried, unemployed and less educated individuals, cannabis use, and childhood adversity. Both phenotypes were associated with genetic liability to schizophrenia.
Conclusions
Schizotypy showed substantial between-sites variation, being more represented in areas where FEP incidence is higher. This supports the hypothesis that shared contextual factors shape the between-sites variation of psychosis across the spectrum.
Secondary surface layers form by replacement of almandine garnet during chemical weathering. This study tested the hypothesis that the kinetic role of almandine’s weathering products, and the consequent relationships of primary-mineral surface texture and specific assemblages of secondary minerals, both vary with the solid-solution-controlled variations in Fe and Al contents of the specific almandine experiencing weathering.
Surface layers are protective (PSL) when the volume of the products formed by replacement is greater than or equal to the volume of the reactants replaced. Under such circumstances, reaction kinetics at the interface between the garnet and the replacing mineral are transport controlled and either transport of solvents or other reactants to, or products from, the dissolving mineral is rate limiting. Beneath PSLs, almandine garnet surfaces are smooth, rounded, and featureless. Surface layers are unprotective (USL) when the volume of the products formed by replacement is less than the volume of the reactants replaced. Under such circumstances, reaction kinetics at the interface between the garnet and the replacing mineral are interface controlled and the detachment of ions or molecules from the mineral surface is rate limiting. Almandine garnet surfaces beneath USLs exhibit crystallographically oriented etch pits. However, contrary to expectations, etch pits occur on almandine garnet grains beneath some layers consisting of mineral assemblages consistent with PSLs.
Based on the Pilling-Bedworth criterion, surface layers are more likely to be protective over a broad range of reactant-mineral compositions when they contain goethite, kaolinite, and pyrolusite. However, this combination requires specific ranges of Fe and Al content of the natural reacting almandine garnet. To form a PSL of goethite and kaolinite, an almandine garnet must have a minimum Al stoichiometric coefficient of ~3.75 a.p.f.u., and a minimum Fe stoichiometric coefficient of ~2.7 a.p.f.u.
Product minerals also influence the mobility of the least-mobile major rock-forming elements. A PSL consisting of goethite, gibbsite, and kaolinite yields excess Al for export during almandine garnet weathering. As the quantity of kaolinite present in the PSL decreases, the amounts of Al available for export increases.
The reactivity of colloidal particles is regulated by their surface properties. These properties affect the wettability, flocculation-dispersion characteristics, ion exchange, sorption capacities and transport of inorganic colloids. Most studies have focused on hydrophilic, charged-particle surfaces, often ignoring the alterations in surface properties produced by the adsorption of natural organic matter, surfactants and other compounds. Adsorption of these substances can potentially render a surface substantially more hydrophobic. Nevertheless, comparatively little is known about changes in surface properties and reactivity of minerals upon sorption of hydrophobic organic compounds. In this study, the properties of four minerals (kaolinite, pyrophyllite, montmorillonite and Min-U-Sil®) and two inorganic materials (X-ray amorphous Al hydroxide and X-ray amorphous Si oxide) were compared before and after treatment with the common silylating agent, trimethylchlorosilane (TMCS). The samples were characterized by measurements of total carbon, cation exchange capacity (CEC), particle size, specific surface area (SSA), electrophoretic mobility, contact angle, particle aggregation, and by X-ray diffraction and diffuse reflectance infrared spectroscopy. For the layer silicates, surface coverage was limited to ∼2% trimethyl silane (TMSi). TMSi covered 7.5% of the Min-U-Sil® surface and 33% of the X-ray amorphous Si oxide. Treatment did not affect the structure of the minerals but reduced the CEC, SSA and electrophoretic mobilities. Water contact angles increased to between 18 and 114° with treatment. While the apolar characteristic of the surfaces decreased minimally with treatment, the Lewis acid/base properties were substantially reduced and interfacial free energy shifted from positive to negative values indicating a more hydrophobic surface character. For all the samples except kaolinite, these changes affected the stability of the colloids in suspension depending upon solution pH. Although the grafting of TMSi altered colloidal mineral surface properties and increased their hydrophobicity, these changes were not sufficient to predict colloid aggregation behavior.
Mild traumatic brain injury (mTBI) is an important public health problem, due to its high incidence and the failure of at least 20% of patients to successfully recover from injury. Cognitive symptoms, in particular, are an important area of research in mTBI, due to their association with return to work and referral to neuropsychological services. Understanding the predictors of cognitive symptoms may help to improve outcomes after mTBI. This study explored female sex, psychological distress, coping style and illness perceptions as potential predictors of cognitive symptoms following adult civilian mTBI.
Participants and Methods:
Sixty-nine premorbidly healthy adults with mTBI (mean age = 36.7, SD = 14.7, range = 18-60; 15 females) were recruited from trauma wards at two public hospitals in Australia and assessed 6-12 weeks following injury. Cognitive complaint was measured using a comprehensive 30-item scale (CCAMCHI) assessing mTBI-specific symptoms in the domains of processing speed, attention, memory and executive function. Participants additionally completed the following measures: Brief-COPE, Illness Perceptions Questionnaire-Revised, Inventory of Depressive Symptomatology, Beck Anxiety Inventory, and PTSD Checklist for DSM-5. The latter three measures were combined to create an index of psychological distress.
Results:
Bivariate nonparametric correlational analyses indicated that female sex (r[67] = .26, 95% CI [.14, .55], p = .03) and psychological distress (r[66] = .54, 95% CI [.40, .72], p < .001) were each significantly associated with cognitive symptom reporting following mTBI. Additionally, while none of the three coping style factors were associated with cognitive symptom reporting, seven of the eight dimensions of illness perceptions were associated with symptom reporting (|r| = .25 - .58, p < 0.05). In a linear regression model assessing the combined effects of each variable, female sex, greater psychological distress, and overall negative illness perceptions were each significant independent predictors of increased cognitive complaint (adj. R2 = .47, F[4,63] = 15.59, p < .001).
Conclusions:
These findings implicate female sex, psychological distress, and illness perceptions as key factors associated with cognitive symptom reporting after mTBI. This research suggests that these factors may be useful in clinical practice when considering early identification of individuals at risk of poor recovery. Specifically, this research implicates females, individuals with high psychological distress, and individuals with negative illness perceptions as important to subgroups to consider for potential intervention after mTBI. Additionally, as psychological distress and illness perceptions are both potentially modifiable, this research suggests that these factors may be useful targets for intervention.