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Mapping reviews (MRs) are crucial for identifying research gaps and enhancing evidence utilization. Despite their increasing use in health and social sciences, inconsistencies persist in both their conceptualization and reporting. This study aims to clarify the conceptual framework and gather reporting items from existing guidance and methodological studies. A comprehensive search was conducted across nine databases and 11 institutional websites, including documents up to January 2024. A total of 68 documents were included, addressing 24 MR terms and 55 definitions, with 39 documents discussing distinctions and overlaps among these terms. From the documents included, 28 reporting items were identified, covering all the steps of the process. Seven documents mentioned reporting on the title, four on the abstract, and 14 on the background. Ten methods-related items appeared in 56 documents, with the median number of documents supporting each item being 34 (interquartile range [IQR]: 27, 39). Four results-related items were mentioned in 18 documents (median: 14.5, IQR: 11.5, 16), and four discussion-related items appeared in 25 documents (median: 5.5, IQR: 3, 13). There was very little guidance about reporting conclusions, acknowledgments, author contributions, declarations of interest, and funding sources. This study proposes a draft 28-item reporting checklist for MRs and has identified terminologies and concepts used to describe MRs. These findings will first be used to inform a Delphi consensus process to develop reporting guidelines for MRs. Additionally, the checklist and definitions could be used to guide researchers in reporting high-quality MRs.
Understanding healthcare personnel’s (HCP) contact patterns are important to mitigate healthcare-associated infectious disease transmission. Little is known about how HCP contact patterns change over time or during outbreaks such as the COVID-19 pandemic.
Methods:
This study in a large United States healthcare system examined the social contact patterns of HCP via standardized social contact diaries. HCP were enrolled from October 2020 to June 2022. Participants completed monthly surveys of social contacts during a representative working day. In June 2022, participants completed a 2-day individual-level contact diary. Regression models estimated the association between contact rates and job type. We generated age-stratified contact matrices.
Results:
Three-hundred and sixty HCP enrolled, 157 completed one or more monthly contact diaries and 88 completed the intensive 2-day diary. In the monthly contact diaries, the median daily contacts were 15 (interquartile range (IQR) 8–20), this increased slightly during the study (slope-estimate 0.004, p-value 0.016). For individual-level contact diaries, 88 HCP reported 2,550 contacts over 2 days. HCP were 2.8 times more likely to contact other HCP (n = 1,592 contacts) than patients (n = 570 contacts). Rehabilitation/transport staff, diagnostic imaging technologists, doctors, nurses, mid-level, and laboratory personnel had higher contacts compared with the lowest contact group (Nursing aids). Contact matrices concentrated in working-age populations.
Conclusions:
HCP contacts concentrate in their work environment, primarily with other HCP. Their contacts remained stable over time even during large changes to societal contact patterns during the COVID-19 pandemic. This stability is critical for designing outbreak and pandemic responses.
Generalized Baumslag-Solitar groups are a class of combinatorially interesting groups. Their group theory is also closely associated to a the topology of a class of 2-dimensional spaces. These 2-dimensional spaces are Seifert fibred. We develop the basic topology of these fibrations and derive some of the most immediate group theoretic consequences of this topology.
This survey article has two components. The first part gives a gentle introduction to Serres notion of $G$-complete reducibility, where $G$ is a connected reductive algebraic group defined over an algebraically closed field. The second part concerns consequences of this theory when $G$ is simple of exceptional type, specifically its role in elucidating the subgroup structure of $G$. The latter subject has a history going back about sixty years. We give an overview of what is known, up to the present day. We also take the opportunity to offer several corrections to the literature.
Every four years leading researchers gather to survey the latest developments in all aspects of group theory. Since 1981, the proceedings of these meetings have provided a regular snapshot of the state of the art in group theory and helped to shape the direction of research in the field. This volume contains selected papers from the 2022 meeting held in Newcastle. It includes substantial survey articles from the invited speakers, namely the mini course presenters Michel Brion, Fanny Kassel and Pham Huu Tiep; and the invited one-hour speakers Bettina Eick, Scott Harper and Simon Smith. It features these alongside contributed survey articles, including some new results, to provide an outstanding resource for graduate students and researchers.
Identifying persons with HIV (PWH) at increased risk for Alzheimer’s disease (AD) is complicated because memory deficits are common in HIV-associated neurocognitive disorders (HAND) and a defining feature of amnestic mild cognitive impairment (aMCI; a precursor to AD). Recognition memory deficits may be useful in differentiating these etiologies. Therefore, neuroimaging correlates of different memory deficits (i.e., recall, recognition) and their longitudinal trajectories in PWH were examined.
Design:
We examined 92 PWH from the CHARTER Program, ages 45–68, without severe comorbid conditions, who received baseline structural MRI and baseline and longitudinal neuropsychological testing. Linear and logistic regression examined neuroanatomical correlates (i.e., cortical thickness and volumes of regions associated with HAND and/or AD) of memory performance at baseline and multilevel modeling examined neuroanatomical correlates of memory decline (average follow-up = 6.5 years).
Results:
At baseline, thinner pars opercularis cortex was associated with impaired recognition (p = 0.012; p = 0.060 after correcting for multiple comparisons). Worse delayed recall was associated with thinner pars opercularis (p = 0.001) and thinner rostral middle frontal cortex (p = 0.006) cross sectionally even after correcting for multiple comparisons. Delayed recall and recognition were not associated with medial temporal lobe (MTL), basal ganglia, or other prefrontal structures. Recognition impairment was variable over time, and there was little decline in delayed recall. Baseline MTL and prefrontal structures were not associated with delayed recall.
Conclusions:
Episodic memory was associated with prefrontal structures, and MTL and prefrontal structures did not predict memory decline. There was relative stability in memory over time. Findings suggest that episodic memory is more related to frontal structures, rather than encroaching AD pathology, in middle-aged PWH. Additional research should clarify if recognition is useful clinically to differentiate aMCI and HAND.
Soft wheat (Triticum aestivum L.) improvement could be enhanced by the identification of germplasm with superior end-use quality traits. Due to the geographic and historical separation of eastern and western US soft wheat germplasm ‘pools’, genetic differences in end-use quality may exist among cultivars arising from these two pools. To identify such differences, 30 US soft wheat cultivars were evaluated in ‘head-to-head’ trials over 3 years in Washington state. Cultivars were classified as: eastern soft red winter (SRW), eastern soft white winter (ESWW), western soft white (WSWW) and western Club. These four soft wheat cultivar classifications clearly differed systematically for some of the quality traits examined. The Club wheat cultivar group had the highest flour yield and flour ash. The Club group also had the lowest mixograph dough water absorption. Milling score (which incorporates break flour yield) was highest for Club and ESWW. Eastern soft red and white wheat cultivar groups had lower flour ash and alkaline water retention capacity (AWRC) compared to the western Club and soft white wheats; ESWW had the lowest AWRC of any classification. Cookie diameter was greatest for the ESWW group, followed by the SRW and Club groups (which were not significantly different), and then by the WSWW group. Individual cultivars with exceptional quality traits were also identified. These results indicate that the four US soft wheat germplasm pools differ, and they may be valuable genetic resources for ‘inter-pool’ wheat improvement.
Caribbean health research has overwhelmingly employed measures developed elsewhere and rarely includes evaluation of psychometric properties. Established measures are important for research and practice. Particularly, measures of stress and coping are needed. Stressors experienced by Caribbean people are multifactorial, as emerging climate threats interact with existing complex and vulnerable socioeconomic environments. In the early COVID-19 pandemic, our team developed an online survey to assess the well-being of health professions students across university campuses in four Caribbean countries. This survey included the Perceived Stress Scale, 10-item version (PSS-10) and the Brief Resilient Coping Scale (BRCS). The participants were 1,519 health professions students (1,144 females, 372 males). We evaluated the psychometric qualities of the measures, including internal consistency, concurrent validity by correlating both measures, and configural invariance using confirmatory factor analysis (CFA). Both scales had good internal consistency, with omega values of 0.91 for the PSS-10 and 0.81 for the BRCS. CFA suggested a two-factor structure of the PSS-10 and unidimensional structure of the BRCS. These findings support further use of these measures in Caribbean populations. However, the sampling strategy limits generalizability. Further research evaluating these and other measures in the Caribbean is desirable.
Levofloxacin prophylaxis reduces bloodstream infections in neutropenic patients with acute myeloid leukemia or relapsed acute lymphoblastic leukemia. A retrospective, longitudinal cohort study compares incidence of bacteremia, multidrug-resistant organisms (MDRO), and Clostridioides difficile (CDI) between time periods of levofloxacin prophylaxis implementation. Benefits were sustained without increasing MDRO or CDI.
Biophysical conditions played a fundamental role in early human colonization of insular territories, particularly in food-producing societies dealing with limited resources and the challenges of maintaining a sustainable carrying capacity. Studies on past human colonization of small oceanic islands thus offer insights into economic plasticity, ecological impacts, and adaptation of early food-producing groups. On the coast of southern Chile, early evidence is dated to 950 cal BP of island colonization by coastal populations with mainland subsistence systems based on the exploitation of marine resources, along with gathering, managing, and cultivating plants and hunting terrestrial animals. Strikingly, the extent to which these mixed economies contributed to insular colonization efforts is largely unknown. Here we used organic residue analysis of ceramic artifacts to shed light on the subsistence of populations on Mocha Island in southern Chile. We extracted and analyzed lipids from 51 pottery sherds associated with the El Vergel cultural complex that flourished in southern Chile between 950 and 400 cal BP. Chemical and stable isotope analysis of the extracts identified a range of food products, including C3 and C4 plants and marine organisms. The results reveal the central role of mixed subsistence systems in fueling the colonization of Mocha Island.
Child care environments offer an ideal setting for feeding interventions. CELEBRATE Feeding is an approach implemented in child care environments in two Maritime Provinces in Canada to support responsive feeding (RF) to foster children’s self-efficacy, self-regulation, and healthy relationships with food. This study aimed to describe RF in child care using established and enhanced scoring frameworks.
The Environment and Policy Assessment and Observation (EPAO) was modified to reflect RF environments and practices, resulting in our modified EPAO and a CELEBRATE scale. Observations were conducted in 18 child care rooms. Behaviours and environments were scored on both scales, creating 21 RF scores, with a score of ‘3’ indicating the most responsiveness. Descriptive analyses of the scores were conducted. The overall room averages were Mean (M) = 41.00, Standard Deviation (SD) = 7.07 (EPAO), and M = 37.92 SD = 6.50 (CELEBRATE). Most responsive scores among rooms within our EPAO and CELEBRATE scales, respectively, were ‘educators not using food to calm or encourage behaviour’ (M = 2.94, SD = 0.24; M = 2.98, SD = 0.06) and ‘not requiring children to sit at the table until finished’ (M = 2.89, SD = 0.47; M = 2.97, SD = 0.12). The least responsive scores within the EPAO were ‘educator prompts for children to drink water’ (M = 0.78, SD = 0.94) and ‘children self-serving’ (M = 0.83, SD = 0.38). The least responsive in the CELEBRATE scale were ‘enthusiastic role modelling during mealtime’ (M = 0.70, SD = 0.68) and ‘praise of mealtime behaviour unrelated to food intake’ (M = 0.74, SD = 0.55). The CELEBRATE scale captured unique observation information about RF to allow documenting change over time with detailed measurement to inform and support nutrition interventions within child care environments.
This study describes the illness burden in the first year of life for children with single-ventricle heart disease, using the metric of days alive and out of hospital to characterize morbidity and mortality.
Methods:
This is a retrospective single-centre study of single-ventricle patients born between 2005 and 2021 who had their initial operation performed at our institution. Patient demographics, anatomical details, and hospitalizations were extracted from our institutional single-ventricle database. Days alive and out of hospital were calculated by subtracting the number of days hospitalized from number of days alive during the first year of life. A multivariable linear regression with stepwise variable selection was used to determine independent risk factors associated with fewer days alive and out of hospital.
Results:
In total, 437 patients were included. Overall median number of days alive and out of hospital in the first year of life for single-ventricle patients was 278 days (interquartile range 157–319 days). In a multivariable analysis, low birth weight (<2.5kg) (b = −37.55, p = 0.01), presence of a dominant right ventricle (b = −31.05, p = 0.01), moderate-severe dominant atrioventricular valve regurgitation at birth (b = −37.65, p < 0.05), index hybrid Norwood operation (b = −138.73, p < 0.01), or index heart transplant (b = −158.41, p < 0.01) were all independently associated with fewer days alive and out of hospital.
Conclusions:
Children with single-ventricle heart defects have significant illness burden in the first year of life. Identifying risk factors associated with fewer days alive and out of hospital may aid in counselling families regarding expectations and patient prognosis.
The Lawson criterion for proton-boron (p-11B) thermonuclear fusion is substantially higher than that for deuterium-tritium (DT) because the fusion cross section is lower and peaks at higher ion energies. The Maxwellian averaged p-11B reactivity peaks at several hundred keV, where bremsstrahlung radiation emission may dominate over fusion reactions if electrons and ions are in thermal equilibrium and the losses are unrestricted. Nonequilibrium burn has often been suggested to realize the benefits of this aneutronic reaction, but the predominance of elastic scattering over fusion reactivity makes this difficult to achieve. The development of ultrashort pulse lasers (USPL) has opened new possibilities for initiating nonequilibrium thermonuclear burns and significant numbers of p-11B alpha particles have been reported from several experiments. We present an analysis that shows that these significant alpha yields are the result of beam fusion reactions that do not scale to net energy gain. We further find that the yields can be explained by experimental parameters and recently updated cross sections such that a postulated avalanche mechanism is not required. We use this analysis to understand the underlying physics of USPL-driven nonequilibrium fusion reactions and whether they can be used to initiate fusion burns. We conclude by outlining a path to increasing the p-11B reactivity towards the goal of achieving ignition and describing the design principles that we will use to develop a computational point design.
Older people with HIV (PWH) are at-risk for Alzheimer’s disease (AD) and its precursor, amnestic mild cognitive impairment (aMCI). Identifying aMCI among PWH is challenging because memory impairment is also common in HIV-associated neurocognitive disorders (HAND). The neuropathological hallmarks of aMCI/AD are amyloid-ß42 (Aß42) plaque and phosphorylated tau (p-tau) accumulation. Neurofilament light chain protein (NfL) is a marker of neuronal injury in AD and other neurodegenerative diseases. In this study, we assessed the prognostic value of the CSF AD pathology markers of lower Aß42, and higher p-tau, p-tau/Aß42 ratio, and NfL levels to identify an aMCI-like profile among older PWH and differentiating it from HAND. We assessed the relationship between aMCI and HAND diagnosis and AD biomarker levels
Participants and Methods:
Participants included 74 PWH (Mean age=48 [SD=8.5]; 87.4% male, 56.5% White) from the National NeuroAIDS Tissue Consortium (NNTC). CSF Aß42, Aß40, p-tau and NfL were measured by commercial immunoassay. Participants completed a neurocognitive evaluation assessing the domains of learning, recall, executive function, speed of information processing, working memory, verbal fluency, and motor. Memory domains were assessed with the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised, and aMCI was defined as impairment (<1.0 SD below normative mean) on two or more memory outcomes among HVLT-R and BVMT-R learning, delayed recall and recognition with at-least one recognition impairment required. HAND was defined as impairment (<1.0 SD below normative mean) in 2 or more cognitive domains. A series of separate linear regression models were used to examine how the levels of CSF p-tau, Aß42, p-tau/Aß42 ratio, and NfL relate to aMCI and HAND status while controlling for demographic variables (age, gender, race and education). Covariates were excluded from the model if they did not reach statistical significance.
Results:
58% percent of participants were diagnosed with HAND, 50.5% were diagnosed with aMCI. PWH with aMCI had higher levels of CSF p-tau/Aß42 ratio compared to PWH without aMCI (ß=.222, SE=.001, p=.043) while controlling for age (ß=.363, p=.001). No other AD biomarker significantly differed by aMCI or HAND status.
Conclusions:
Our results indicate that the CSF p-tau/Aß42 ratio relates specifically to an aMCI-like profile among PWH with high rates of cognitive impairment across multiple domains in this advanced HIV disease cohort. Thus, the p-tau/Aß42 ratio may have utility in disentangling aMCI from HAND and informing the need for further diagnostic procedures and intervention. Further research is needed to fully identify, among a broader group of PWH, who is at greatest risk for aMCI/AD and whether there is increased risk for aMCI/AD among PWH as compared to those without HIV.
Many people with HIV (PWH) are at risk for age-related neurodegenerative disorders such as Alzheimer’s disease (AD). Studies on the association between cognition, neuroimaging outcomes, and the Apolipoprotein E4 (APOE4) genotype, which is associated with greater risk of AD, have yielded mixed results in PWH; however, many of these studies have examined a wide age range of PWH and have not examined APOE by race interactions that are observed in HIV-negative older adults. Thus, we examined how APOE status relates to cognition and medial temporal lobe (MTL) structures (implicated in AD pathogenesis) in mid- to older-aged PWH. In exploratory analyses, we also examined race (African American (AA)/Black and non-Hispanic (NH) White) by APOE status interactions on cognition and MTL structures.
Participants and Methods:
The analysis included 88 PWH between the ages of 45 and 68 (mean age=51±5.9 years; 86% male; 51% AA/Black, 38% NH-White, 9% Hispanic/Latinx, 2% other) from the CNS HIV Antiretroviral Therapy Effects Research multi-site study. Participants underwent APOE genotyping, neuropsychological testing, and structural MRI; APOE groups were defined as APOE4+ (at least one APOE4 allele) and APOE4- (no APOE4 alleles). Eighty-nine percent of participants were on antiretroviral therapy, 74% had undetectable plasma HIV RNA (<50 copies/ml), and 25% were APOE4+ (32% AA/Black/15% NH-White). Neuropsychological testing assessed seven domains, and demographically-corrected T-scores were calculated. FreeSurfer 7.1.1 was used to measure MTL structures (hippocampal volume, entorhinal cortex thickness, and parahippocampal thickness) and the effect of scanner was regressed out prior to analyses. Multivariable linear regressions tested the association between APOE status and cognitive and imaging outcomes. Models examining cognition covaried for comorbid conditions and HIV disease characteristics related to global cognition (i.e., AIDS status, lifetime methamphetamine use disorder). Models examining the MTL covaried for age, sex, and
relevant imaging covariates (i.e., intracranial volume or mean cortical thickness).
Results:
APOE4+ carriers had worse learning (ß=-0.27, p=.01) and delayed recall (ß=-0.25, p=.02) compared to the APOE4- group, but APOE status was not significantly associated with any other domain (ps>0.24). APOE4+ status was also associated with thinner entorhinal cortex (ß=-0.24, p=.02). APOE status was not significantly associated with hippocampal volume (ß=-0.08, p=0.32) or parahippocampal thickness (ß=-0.18, p=.08). Lastly, race interacted with APOE status such that the negative association between APOE4+ status and cognition was stronger in NH-White PWH as compared to AA/Black PWH in learning, delayed recall, and verbal fluency (ps<0.05). There were no APOE by race interactions for any MTL structures (ps>0.10).
Conclusions:
Findings suggest that APOE4 carrier status is associated with worse episodic memory and thinner entorhinal cortex in mid- to older-aged PWH. While APOE4+ groups were small, we found that APOE4 carrier status had a larger association with cognition in NH-White PWH as compared to AA/Black PWH, consistent with studies demonstrating an attenuated effect of APOE4 in older AA/Black HIV-negative older adults. These findings further highlight the importance of recruiting diverse samples and suggest exploring other genetic markers (e.g., ABCA7) that may be more predictive of AD in some races to better understand AD risk in diverse groups of PWH.
Social Network Analysis is a method of analyzing coauthorship networks or relationships through graph theory. Institutional Development Award (IDeA) Networks for Clinical and Translational Research (IDeA-CTR) was designed to expand the capability for clinical and translational research to enhance National Institutes of Health funding.
Methods:
All publications from a cohort of clinical and translational scientists in Oklahoma were collected through a PubMed search for 2014 through 2021 in October 2022. For this study’s bibliometric portion, we pulled the citations from iCite in November of 2022.
Results:
There were 2,391 articles published in 1,019 journals. The number of papers published by year increased from 56 in 2014 to 448 in 2021. The network had an average of 6.4 authors per paper, with this increasing by year from 5.3 in 2014 to 6.9 in 2021. The average journal impact factor for the overall network was 7.19, with a range from 0.08 to 202.73. The Oklahoma Shared Clinical and Translational Resources (OSCTR) network is a small world network with relatively weak ties.
Conclusions:
This study provides an overview of coauthorship in an IDeA-CTR collaboration. We show the growth and structure of coauthorship in OSCTR, highlighting the importance of understanding and fostering collaboration within research networks.