Total Recall Research Articles

A multistage retrieval system for health-related misinformation detection

Web search is widely used to find online medical advice. As such, health-related information access requires retrieval algorithms capable of promoting reliable documents and filtering out unreliable ones. To this end, different types of components, such as query-document matching features, passage relevance estimation and AI-based reliability estimators, need to be combined. In this paper, we propose an entire pipeline for misinformation detection, based on the fusion of multiple content-based features. We present experiments which study the influence of each pipeline stage for the target task.Our technological solution incorporates signals from technologies derived from diverse research fields, including search, deep learning for natural language processing, as well as advanced supervised and unsupervised learning. To combine evidence, different score fusion strategies are compared, including unsupervised rank fusion techniques and learning-to-rank methods. The reference framework for empirically validating our solution is the TREC Health Misinformation Track, which provides several challenging subtasks that foster research on the identification of reliable and correct information for health-related decision making tasks. More specifically, we address a total recall task, the goal of which is to identify all the documents conveying incorrect information for a specific set of topics, and an ad-hoc retrieval task, aiming to rank credible and correct information over incorrect information. All variants are evaluated with an assorted set of effectiveness metrics, which includes standard search measures, such as R-Precision, Average Precision or Normalised Discounted Cumulative Gain, and innovative metrics based on the compatibility between the ranked output and two reference rankings composed of helpful and harmful documents, respectively.Our experiments demonstrate the effectiveness of the proposed pipeline stages and indicate that sophisticated supervised fusion methods do not fare better than simpler fusion alternatives. Additionally, for reliability estimation, unsupervised textual similarity performs better than textual classification based on supervised learning. The results also show that the presented approach is highly competitive when compared with state-of-the-art solutions for the same problem.

A search of only four key databases would identify most randomized controlled trials of acupuncture: A meta-epidemiological study.

Little research has been conducted to assess which specific databases should be searched when performing a systematic review (SR) on acupuncture. The current study aimed to identify key databases and the optimal database combination to retrieve randomized controlled trials (RCTs) on acupuncture for inclusion in SRs. A systematic search for SRs in the field of acupuncture was conducted in order to identify target databases and RCTs were extracted from the SRs that had searched all target databases. The proportions of SRs that had achieved 100%, 95%, or 90% recall of RCTs and the total recall of RCTs in various combinations of target databases were calculated. Sensitivity analysis was performed on those SRs that included 10 or more RCTs. CNKI, WanFang, VIP, PubMed, CENTRAL and Embase were regarded as target databases. A total of 4349 acupuncture RCTs were extracted from 286 SRs. Searching all six target databases retrieved 99.3% of all RCTs while 99.1% were recalled by searching the combination of CNKI, WanFang, PubMed and CENTRAL. There were no significant differences on total recall of RCTs (p=0.549) or in the proportion of SRs with 90% recall of RCTs (97.2% vs. 97.6%; p=0.794) between searching the above four and the full six target databases. Most results were similar in the sensitivity analysis. The combined retrieval power of CNKI, WanFang, PubMed and CENTRAL was considered an efficient choice to retrieve acupuncture RCTs included in SRs.

A-38 Sport-related Concussion as a Stressor: Differential Memory for Emotion and Neutral Words

Abstract Purpose: To explore if the acute stress associated with sport-related concussion (SRC) leads to differential memory for neutral versus emotion words. Based on a Roozendaal and colleagues’ (2002) model of stress and memory, we hypothesized: Following SRC, athletes will demonstrate better recall for neutral compared to emotion words at immediate recall but demonstrate the reverse pattern on delayed recall, with better recall for emotion compared to neutral words. Methods: 80 (73 Males,7 Females) collegiate athletes completed a neuropsychological evaluation within 14 days of SRC. Two verbal learning and memory tasks were administered: neutral words [Hopkins Verbal Learning Test-Revised (HVLT-R)] and emotion words [Affective Word List (AWL)]. Both tasks had three learning trials and a delayed (20–25 minutes) recall. Paired samples t-tests were conducted to compare memory for emotion words (AWL) and neutral words (HVLT-R): AWL Total Immediate Recall vs. HVLT-R Total Immediate Recall and AWL Delayed Recall vs. HVLT-R Delayed Recall. Results: Following concussion, athletes’ memory for neutral words (M = 94.92, SD = 16.17) did not significantly differ from memory for emotion words (M = 96.83, SD = 18.28) on immediate recall trials, (t(79) = −0.91, p = 0.37, d = 0.11). However, memory for emotion words (M = 96.83, SD = 16.98) was significantly better than memory for neutral words (M = 90.84, SD = 20.58) after a delay, (t(79) = 2.97, p = 0.004, d = −0.33). Conclusions: Our results demonstrate that the stress associated with SRC differentially impacts delayed retrieval of neutral compared to emotion words. Because memory is often impaired following SRC, a more nuanced examination of learning and memory can help clinicians understand neuropsychological deficits associated with SRC, and possibly have implications for addressing memory difficulties.

Natural Language Processing Approaches for Retrieval of Clinically Relevant Genomic Information in Cancer.

The accelerating impact of genomic data in clinical decision-making has generated a paradigm shift from treatment based on the anatomic origin of the tumor to the incorporation of key genomic features to guide therapy. Assessing the clinical validity and utility of the genomic background of a patient’s cancer represents one of the emerging challenges in oncology practice, demanding the development of automated platforms for extracting clinically relevant genomic information from medical texts. We developed PubMiner, a natural language processing tool to extract and interpret cancer type, therapy, and genomic information from biomedical abstracts. Our initial focus has been the retrieval of gene names, variants, and negations, where PubMiner performed highly in terms of total recall (91.7%) with a precision of 79.7%. Our next steps include developing a web-based interface to promote personalized treatment based on each tumor’s unique genomic fingerprints.

Modified cued recall test in the French population with Down syndrome: A retrospective medical records analysis.

Adults with Down syndrome (DS) are at increased risk of developing Alzheimer's disease (AD) due to genetic predisposition. Identification of patients with AD is difficult since intellectual disabilities (ID) may confound diagnosis. The objective of this study was to evaluate the ability of the French version of the modified cued recall test (mCRT) to distinguish between subjects with and without AD in the adult DS population. This was a retrospective, single-centre, medical records study including data between March 2014 and July 2020. Adults aged ≥30years with DS who had at least one mCRT record available were eligible. Age, sex and ID level were extracted, and subjects were attributed to three groups: patients with AD, patients with co-occurring conditions that may impact cognitive function and subjects without AD. mCRT scores, adjusted by sex, age and ID level, were compared between groups. The optimal cut-off value to distinguish between patients with and without AD was determined using the receiver operating characteristic curve. The impact of age and ID level on mCRT scores was assessed. Overall, 194 patients with DS were included: 12 patients with AD, 94 patients with co-occurring conditions and 88 healthy subjects. Total recall scores were significantly lower (P<0.0001) in patients with AD compared with healthy subjects. The optimal cut-off value to discriminate between patients with AD and healthy subjects was 22, which compares well with the cut-off value of 23 originally reported for the English version of the mCRT. Patients aged 30-44years had higher mCRT total recall scores compared with patients aged ≥45years (P=0.0221). Similarly, patients with mild ID had higher mCRT scores compared with patients with severe ID (P<0.0001). The mCRT is a sensitive tool that may help in the clinical diagnosis of AD in subjects with DS. Early recognition of AD is paramount to deliver appropriate interventions to this vulnerable population.

Trajectory Pattern of Cognitive Decline in Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy.

Background and ObjectivesThe course and pattern of cognitive decline in ischemic cerebral small vessel disease remain poorly characterized. We analyzed the trajectory pattern of cognitive decline from age 25 to 75 years in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).MethodsWe applied latent process mixed models to data obtained from patients with CADASIL who were repeatedly scored during their follow-up using 16 selected clinical scales or cognitive tests.ResultsThe modeled evolutions of these scores obtained from 1,243 observations in 265 patients recruited at the French National Referral Centre (50.1 years on average and 45.3% men) showed wide and heterogeneous variations in amplitude along the age-related progression of the disease. Although the Backward Digit Span remained essentially stable, a linear deterioration of scores obtained using the Symbol Digit Numbers or Number of Errors of Trail Making Test B was detected from 25 to 75 years. By contrast, the largest score changes were observed at midlife using the Digit Cancellation Task. All other tests related to executive functions, memory performances, or global cognitive efficiency showed a rate of change accelerating especially at the advanced stage of the disease. Male gender and the presence of gait disorders or of some disability at baseline were found to predict earlier or large changes of 4 scores (Index of Sensitivity to Cueing, Delayed Total Recall, Initiation/Perseveration, and Barthel Index) in a subgroup of individuals distinct from the rest of the sample.DiscussionCognitive alterations develop heterogeneously during the progression of CADASIL and vary largely according to the stage of the disease. These results suggest that not only the target population and study duration but also the stage of disease progression should be considered in preparing future clinical trials aimed at reducing cognitive decline in any such condition.

Test-Retest Reliability and Minimal Detectable Change of Four Cognitive Tests in Community-Dwelling Older Adults.

Cognitive test-retest reliability measures can be used to evaluate meaningful changes in scores. This analysis aimed to develop a comprehensive set of test-retest reliability values and minimal detectable change (MDC) values for a cognitive battery for community-dwelling older individuals in Australia and the U.S., for use in clinical practice. Cognitive scores collected at baseline and year 1, in the ASPirin in Reducing Events in the Elderly clinical trial were used to calculate intraclass correlation coefficients (ICC) for four tests: Modified Mini-Mental State examination (3MS), Hopkins Verbal Learning Test-Revised (HVLT-R), single-letter Controlled Oral Word Association Test (COWAT-F), and Symbol Digit Modalities Test (SDMT). 16,956 participants aged 70 years and over (65 years and over for U.S. minorities) were included. ICCs were used to calculate MDC values for eight education and ethno-racial subgroups. All four cognitive tests had moderate (ICC > 0.5) to good (ICC > 0.7) test-retest reliability. ICCs ranged from 0.53 to 0.63 (3MS), 0.68 to 0.77 (SDMT), 0.56 to 0.64 (COWAT-F), 0.57 to 0.69 (HVLT-R total recall), and 0.57 to 0.70 (HVLT-R delayed recall) across the subgroups. MDC values ranged from 6.60 to 9.95 (3MS), 12.42 to 15.61 (SDMT), 6.34 to 8.34 (COWAT-F), 8.13 to 10.85 (HVLT-R total recall), and 4.00 to 5.62 (HVLT-R delayed recall). This large cohort of older individuals provides test-retest reliability and MDC values for four widely employed tests of cognitive function. These results can aid interpretation of cognitive scores and decline instead of relying on cross-sectional normative data alone.

The Development of Family Mediation in the UK My personal story as one of the 'Early Settlers'

This article describes a very personal reflective narrative and should not be regarded as representing the views of any other person or organisation. Over recent years several colleagues have encouraged me to write this history, since it could be lost from the records forever. I am not claiming total recall of every event and readers may have different recollections. It provides an account of the creation and subsequent achievements of the College of Mediators (COM), formerly the UK College of Family Mediators (UKCFM), including an attempt to force its closure. As an elected member of the Board of Trustees, I have the benefit of all minutes of Governors meetings over that troubled period.

Omega-3 Supplementation for the Prevention of Cognitive Decline in Older Adults: Does It Depend on Homocysteine Levels?

Recent evidence point towards an interaction between omega-3 (n-3) polyunsaturated fatty acids (PUFA) and plasma homocysteine (Hcy). This study tested the hypothesis that effects of red blood cell n-3 PUFA are modified according to baseline plasma Hcy in the large Mulit-domain Alzheimer Prevention Trial (MAPT) throughout the 3-years of treatment with an additional 2 years of observational follow-up. Experimental study. From the 1680 participants that were randomized in the four groups of the MAPT study (two of which received n-3 PUFA, the other two without n-3 PUFA), 782 were selected because they had baseline data on both Hcy and n-3 PUFA. Cognitive performance was measured with a broad set of cognitive tests including free and total recall of the cued selective reminding test, digit symbol substitution test, category naming test and Trail-making tests (TMT-A and B) and Clinical dementia rating scale. We found a significant association between TMT-A and red blood cell n-3 PUFA levels in participants with Hcy values ≤16.8 µMol/L after adjustments at baseline (Estimate: -1.3, 95% CI: -2.3; -0.3, p=0.01). Additionally, participants with high Hcy values had a significant worsening after adjustments in TMT-B after a 5-year n-3 PUFA supplementation, compared to low levels of Hcy (Mean difference: 34.8, 95% CI: 7.8;61.7). This study shows that Hcy levels could modify the association between red blood cell n-3 PUFA and executive function. People with high Hcy may benefit less from a n-3 PUFA supplementation to prevent cognitive decline.

Serial and strategic memory processes in goal-directed selective remembering

People often rely on habitual, serial processing when presented with to-be-learned information. We tested how strategic processing can override more bottom-up, serial processes when remembering information by having participants study a list of word triads (e.g., “dollar phone pizza”). Participants' goal was manipulated by maximizing either (i) their recall for each of the studied words or (ii) their total score associated with recalling certain words in each triad that were more valuable (worth more points) to engage either serial or strategic processing and retrieval mechanisms. Results revealed that when learners were told to maximize their total recall, they frequently engaged in serial remembering—remembering guided by an item's location within the study phase (i.e., words were retrieved according to a habitual reading bias). However, when words were paired with point values that counted towards participants' scores if recalled, participants were not only selective for high-value words but also attempted to overcome the tendency to engage in serial remembering; instead, they appeared to engage in strategic remembering whereby retrieval is guided by value. Thus, to maximize memory utility, it may be beneficial to override habitual processes and initiate retrieval with high-value words, and when making recall transitions, to recall high-value words together. Importantly, when certain to-be-remembered words were more valuable than their neighbors, participants still demonstrated some serial processing of the to-be-remembered words, indicating that even when engaging in strategic memory, some habitual processes can persist.

Effect of physical exercise on cognitive function after chemotherapy in patients with breast cancer: a randomized controlled trial (PAM study)

BackgroundUp to 60% of breast cancer patients treated with chemotherapy is confronted with cognitive problems, which can have a significant impact on daily activities and quality of life (QoL). We investigated whether exercise training improves cognition in chemotherapy-exposed breast cancer patients 2–4 years after diagnosis.MethodsChemotherapy-exposed breast cancer patients, with both self-reported cognitive problems and lower than expected performance on neuropsychological tests, were randomized to an exercise or control group. The 6-month exercise intervention consisted of supervised aerobic and strength training (2 h/week), and Nordic/power walking (2 h/week). Our primary outcome was memory functioning (Hopkins Verbal Learning Test-Revised; HVLT-R). Secondary outcomes included online neuropsychological tests (Amsterdam Cognition Scan; ACS), self-reported cognition (MD Anderson Symptom Inventory for multiple myeloma; MDASI-MM), physical fitness (relative maximum oxygen uptake; VO2peak), fatigue (Multidimensional Fatigue Inventory), QoL (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire; EORTC QLQ C-30), depression (Patient Health Questionnaire-9, Hospital Anxiety and Depression Scale; HADS), and anxiety (HADS). HVLT-R total recall was analyzed with a Fisher exact test for clinically relevant improvement (≥ 5 words). Other outcomes were analyzed using multiple regression analyses adjusted for baseline and stratification factors.ResultsWe randomized 181 patients to the exercise (n = 91) or control group (n = 90). Two-third of the patients attended ≥ 80% of the exercise sessions, and physical fitness significantly improved compared to control patients (B VO2peak 1.4 ml/min/kg, 95%CI:0.6;2.2). No difference in favor of the intervention group was seen on the primary outcome. Significant beneficial intervention effects were found for self-reported cognitive functioning [MDASI-MM severity (B-0.7, 95% CI − 1.2; − 0.1)], fatigue, QoL, and depression. A hypothesis-driven analysis in highly fatigued patients showed positive exercise effects on tested cognitive functioning [ACS Reaction Time (B-26.8, 95% CI − 52.9; − 0.6) and ACS Wordlist Learning (B4.4, 95% CI 0.5; 8.3)].ConclusionsA 6-month exercise intervention improved self-reported cognitive functioning, physical fitness, fatigue, QoL, and depression in chemotherapy-exposed breast cancer patients with cognitive problems. Tested cognitive functioning was not affected. However, subgroup analysis indicated a positive effect of exercise on tested cognitive functioning in highly fatigued patients.Trial Registration Netherlands Trial Registry: Trial NL5924 (NTR6104). Registered 24 October 2016, https://www.trialregister.nl/trial/5924.

0056 Rest-Activity Rhythms (RARs) and Cognitive Functions in Early Post-menopausal Women

Abstract Introduction RAR disruptions are more common among individuals with dementia than healthy individuals. In healthy older women, RAR disruption predicted future diagnosis of Mild Cognitive Impairment (MCI). With no cure for Alzheimer’s Disease, it is crucial to identify modifiable risk-factors for early prevention of cognitive decline. Here we aim to determine whether RAR disruption was associated with cognitive status and cognitive performance in early post-menopausal women, thereby representing a modifiable risk factor for dementia. Methods The sample drawn from MsBrain study, included 229 cognitively unimpaired women and 42 women with MCI/dementia, based on score on Montreal Cognitive Assessment (MOCA) adjusted for age and race. Participants completed a 72-hour wrist actigraphy monitoring and neuropsychological assessment including: California Verbal Learning Test (CVLT), Letter Number Sequencing (LNS), Card Rotation Test, Symbol Digit Modalities Test (SDMT). Latent profile analysis (LPA) was performed using five nonparametric RAR variables (intra-daily variability (IV), inter-daily stability (IS), relative amplitude (RA), alpha and F-statistic). The association between RAR clusters and cognitive performance and the relationship between RAR clusters, cognitive status and race/ethnicity were assessed using linear regression models, controlling for age, race/ethnicity, education and body mass index (BMI); and using chi-square test respectively. Results LPA revealed three clusters: Robust with high F-Stat, RA and IS and low IV; Normal;Weak with low RA and high alpha. The proportion of subjects with MCI/dementia did not differ between clusters however there was a significant association between race and RAR clusters, X2 (2, N = 271)=14.18, p&amp;lt;0[P1] .001, with non-white women more likely than white women to belong in the Weak group (p &amp;lt; .01). In an adjusted analysis of healthy women, the Weak group performed worse than the Robust group in LNS control (p&amp;lt;.050 ). In the unadjusted model, the Weak group performed worse than Robust group in CVLT Total Learning and Long Delay Recall and SDMT (p=.0074, p=.011and p= .0041, respectively). Conclusion Non-white women had weaker RAR than their white counterparts. Weaker RARs related to poorer working memory as measured by LNS; and poorer verbal memory and processing speed, measured by CVLT and SDMT however these effects were largely influenced by covariates, particularly race/ethnicity and education. Support (If Any)

The Free and Cued Selective Reminding Test: Discriminative Values in a Naturalistic Cohort.

Neuropsychological assessment is still the basis for the first evaluation of patients with cognitive complaints. The Free and Cued Selective Reminding Test (FCSRT) generates several indices that could have different accuracy in the differential diagnosis between Alzheimer's disease (AD) and other disorders. In a consecutive series of naturalistic patients, the accuracy of the FCSRT indices in differentiating patients with either mild cognitive impairment (MCI) due to AD or AD dementia from other competing conditions was evaluated. We evaluated the accuracy of the seven FCSRT indices in differentiating patients with AD from other competing conditions in 434 consecutive outpatients, either at the MCI or at the early dementia stage. We analyzed these data through the receiver operating characteristics curve, and we then generated the odds-ratio map of the two indices with the best discriminative value between pairs of disorders. The immediate and the delayed free total recall, the immediate total recall, and the index of sensitivity of cueing were the most useful indices and allowed to distinguish AD from dementia with Lewy bodies and psychiatric conditions with very high accuracy. Accuracy was instead moderate in distinguishing AD from behavioral variant frontotemporal dementia, vascular cognitive impairment, and other conditions. By using odd-ratio maps and comparison-customized cut-off scores, we confirmed that the FCSRT represents a useful tool to characterize the memory performance of patients with MCI and thus to assist the clinician in the diagnosis process, though with different accuracy values depending on the clinical hypothesis.

Effects of Aerobic Walking on Memory, Subjective Cognitive Complaints, and Brain-Derived Neurotrophic Factor Among Older Hypertensive Women

Background:Hypertension is prevalent in older women and is associated with increased cognitive impairment. Exercise has demonstrated beneficial effects on cognitive function, but the impact of exercise on older hypertensive women remains unclear. We investigated the effects of an aerobic walking program on memory, subjective cognitive complaints, and brain-derived neurotrophic factor in older hypertensive women. Methods: A quasi-experimental study with a pretest-posttest design was conducted. Older hypertensive women were randomly assigned to the aerobic walking group or a control group with routine care. The intervention group received a 24-week aerobic walking program. Data were collected at baseline and 24 weeks after enrollment. Participants' characteristics, memory, subjective cognitive complaints, and plasma brain-derived neurotrophic factor were analyzed. Results: The aerobic walking group (n = 30) reported improvements in total recall, delayed recall, and subjective cognitive impairment after 24 weeks of aerobic walking. Compared to the control group (n = 28), the aerobic walking group showed significantly greater improvement in delayed recall at 24 weeks. However, aerobic walking had no significant effect on subjective cognitive complaints or brain-derived neurotrophic factor. Conclusion: The aerobic walking training significantly improved memory performance among older women with hypertension. A longer randomized controlled trial with a larger sample is necessary to confirm and further explore the effects of this intervention.

An adapted Arabic version of the Test of Nine Images for the illiterate Lebanese population: Validation and preliminary normative data.

In the absence of a simple validated instrument to screen for cognitive impairment among illiterate Lebanese older adults, the aims of this study were to validate an Arabic version of the Test of Nine Images (A-TNI93) adapted by the Working Group on Dementia at Saint Joseph University: Groupe de Travail sur les Démences de l'Univesité Saint Joseph (GTD-USJ) for illiterate older Lebanese and to establish normative data. A national population-based sample of 332 community-dwelling illiterate Lebanese aged 55 years and older was administered the A-TNI93 (GTD-USJ) scoring free and overall recall. The sample is part of a larger national sample (1342 participants) used to validate an Arabic version of the Mini-Mental State Examination already reported. Reproducibility, sensitivity, specificity, and area under the curve of the A-TNI93 (GTD-USJ) scoring to detect cognitive impairment according to Clinical Dementia Rating (CDR) as the gold standard were measured. Normative data were established among 188 cognitively normal participants. A threshold score of six on free recall (FR) provided a sensitivity of 66.7% and a specificity of 90.5%. The area under the curve was 0.93. By taking either scores, that is, a FR ≤ 6 or a total recall ≤ 8, the A-TNI93 (GTD-USJ) slightly improved dementia case detection with a sensitivity of 70.8% and a specificity of 88%. Normative data illustrate the distribution of cognitive performance among illiterate older adults. Compared to the CDR requiring physician's competence, the A-TNI93 (GTD-USJ) is a valid Arabic adaptation to screen for cognitive impairment among illiterate Lebanese older adults.

Latent Mixture Modeling to Identify Homogeneous Subgroups Predictive of Cerebrovascular Reactivity

IntroductionPrecision medicine is a growing topic of research within the medical community. However, the complex factors that influence disease progression and treatment efficacy often make the identification of small subgroups within large clinical populations challenging. Without strategies to identify subgroups that differentially respond to intervention, researchers and clinicians could overlook treatments that may benefit specific aspects within sizable clinical populations. Cerebrovascular disease results from the interaction of multiple risk factors, leading to varying pathologies including stroke and dementia. Identifying subgroups within the scope of cerebrovascular dysfunction risk will allow researchers to better identify individuals at risk for cerebrovascular disease and ultimately inform optimal treatment strategies. Latent mixture modeling (LMM) presents a novel, unbiased method to identify small homogeneous subgroups that have similar traits within the context of large heterogeneous cohorts. Using LMM, it is possible to detect the presence of latent categorical variables which correspond to unobserved subgroups. To assess the feasibility of LMM as a technique for forming subgroups that predict cerebrovascular health, we retrospectively analyzed data from 78 individuals including 12 measures of physical, metabolic, and cognitive health. Our hypothesis was that latent mixture modeling would identify subgroups formed around similar characteristics of physical, metabolic, cognitive, and psychological health. Further, we hypothesized that these subgroups would display differences in cerebrovascular reactivity (CVR).MethodsData from previous experiments conducted in our laboratory between 2018‐2020 were organized and prepared for analysis. Health measures included: body mass index, systolic blood pressure, heart rate, non‐HDL cholesterol, white blood cell count, albumin/globulin ratio, blood glucose, serum creatinine, total recall memory score, and patient‐reported perception of fear and anxiety. CVR was measured by transcranial Doppler ultrasound and calculated as the percent change (from baseline) in middle cerebral artery blood velocity (MCAv) per mmHg following a forced +9mmHg increase in end‐tidal CO2. LMM was used to identify latent classes based on the selected health measures, and then to assess whether CVR differed among the identified classes. The number of classes was picked based after examining a number of criteria including: Akaike, Bayesian, Sample Size Adjusted Bayesian Information Criteria, Entropy, and the VLMR and adjusted VLMR likelihood ratio tests. The BCH procedure was used for post‐hoc comparisons among classes.ResultsWe identified 4 homogeneous subgroup classes within our data. CVR was found to be significantly different when comparing class 1 and class 2 (p= 0.012) and there was a trend towards significance when comparing class 2 and class 4 (p= 0.063). These data suggest that the interaction of healthspan indicators influence differences in cerebrovascular endothelial function.

Dug: a semantic search engine leveraging peer-reviewed knowledge to query biomedical data repositories.

As the number of public data resources continues to proliferate, identifying relevant datasets across heterogenous repositories is becoming critical to answering scientific questions. To help researchers navigate this data landscape, we developed Dug: a semantic search tool for biomedical datasets utilizing evidence-based relationships from curated knowledge graphs to find relevant datasets and explain why those results are returned. Developed through the National Heart, Lung and Blood Institute's (NHLBI) BioData Catalyst ecosystem, Dug has indexed more than 15 911 study variables from public datasets. On a manually curated search dataset, Dug's total recall (total relevant results/total results) of 0.79 outperformed default Elasticsearch's total recall of 0.76. When using synonyms or related concepts as search queries, Dug (0.36) far outperformed Elasticsearch (0.14) in terms of total recall with no significant loss in the precision of its top results. Dug is freely available at https://github.com/helxplatform/dug. An example Dug deployment is also available for use at https://search.biodatacatalyst.renci.org/. Supplementary data are available at Bioinformatics online.

Segmenting Individual Tree from TLS Point Clouds Using Improved DBSCAN

Terrestrial laser scanning (TLS) can provide accurate and detailed three-dimensional (3D) structure information of the forest understory. Segmenting individual trees from disordered, discrete, and high-density TLS point clouds is the premise for obtaining accurate individual tree structure parameters of forest understory, pest control and fine modeling. In this study, we propose a bottom-up method to segment individual trees from TLS forest data based on density-based spatial clustering of applications with noise (DBSCAN). In addition, we also improve the DBSCAN based on the distance distribution matrix (DDM) to automatically and adaptively determine the optimal cluster number and the corresponding input parameters. Firstly, the proposed method is based on the improved DBSCAN to detect the trunks and obtain the initial clustering results. Then, the Hough circle fitting method is used to modify the trunk detection results. Finally, individual tree segmentation is realized based on regional growth layer-by-layer clustering. In this paper, we use TLS multi-station scanning data from Chinese artificial forest and German mixed forest, and then evaluate the efficiency of the method from three aspects: overall segmentation, trunk detection and small tree segmentation. Furthermore, the proposed method is compared with three existing individual tree segmentation methods. The results show that the total recall, precision, and F1-score of the proposed method are 90.84%, 95.38% and 0.93, respectively. Compared with traditional DBSCAN, recall, accuracy and F1-score are increased by 6.96%, 4.14% and 0.06, respectively. The individual tree segmentation result of the proposed method is comparable to those of the existing methods, and the optimal parameters can be automatically extracted and the small trees under tall trees can be accurately segmented.

Association of Emerging β-Amyloid and Tau Pathology With Early Cognitive Changes in Clinically Normal Older Adults.

Alzheimer disease (AD) clinical trials are moving earlier in the disease process according to emerging signs of β-amyloid (Aβ) and tau pathology. If early treatment is the right time for intervention, it is critical to find the right test to optimize cognitive outcome measures for clinical trials. We sought to identify cognitive measures associated with the earliest detectable signs of emerging Aβ and tau pathology. One hundred twelve clinically normal adults with longitudinal Pittsburgh compound B (PiB)-PET, 18F-flortaucipir (FTP)-PET, and cognitive data for ≥7 years were included from the Harvard Aging Brain Study (HABS). Analyses assessed those initially classified as PiB- (less than Centiloid [CL] 20) and then expanded to include PiB+ individuals up to CL40, the approximate threshold beyond which neocortical tau proliferation begins. Separate linear mixed-effects models assessed the effects of emerging global Aβ (PiB slope) and tau (baseline FTP level and FTP slope) in the entorhinal and inferior temporal (IT) cortices on multiple cognitive tasks and the Preclinical Alzheimer's Cognitive Composite (PACC) over time. Steeper PiB slopes were associated with declining processing speed (Digit Symbol Substitution Test [DSST], Trail Making Test Part A) in those <CL20 and expanded to include learning/memory retrieval (FCSRT-FR], Selective Reminding Test Total Recall [SRT-tr], Logical Memory Immediate Recall) in the <CL40 group. FTP had limited effects under CL20, with only rising right IT FTP slope related to declining FCSRT-FR and SRT-tr learning/memory retrieval. When we expanded to include those initially <CL40, rising FTP level or slope was related to declines across all tasks, and PiB slope effects on memory retrieval but not DSST score were reduced. A composite measure of processing speed and memory retrieval tasks provided the strongest prediction of decline under CL40, while PACC score remained optimal at high levels of Aβ (>CL40). Early, Aβ-mediated cognitive slowing was detected for processing speed measures, while early memory retrieval declines were associated with emerging Aβ and tau pathology. Composites of these measures may help determine whether anti-Aβ or anti-tau therapies administered at the first signs of pathology might preserve cognitive function. This study provides Class I evidence that in clinically normal older adults, emerging PET-detected AD pathology is associated with declining processing speeds and memory retrieval.

State anxiety may not affect memory encoding, retrieval, or recognition in older adults with mood disorders

<h3>Introduction</h3> State-level anxiety can have broad effects on cognition that are both beneficial (e.g., Yerkes-Dodson law) and detrimental. Data from functional brain imaging and physiological studies suggest state anxiety affects memory performance; however, findings have been inconsistent, and any effects likely depend on the specific memory process being examined (e.g., encoding, retrieval, and retention) and sample characteristics (e.g., age, clinical status). In this vein, few studies have examined how state anxiety affects memory in older adults, and even fewer have focused on patients with late life mood disorders. Moreover, the literature in this regard has produced inconsistent and sometimes conflicting findings, with some studies suggesting a detrimental impact on recall and others suggesting no effect or even modest benefit. Further investigation is needed to better understand how different memory processes might be impacted by state anxiety in older adults with mood disorders. This is an important target of investigation, as accounting for affective state is essential to ascertaining the clinical significance of memory deficits observed during neuropsychological evaluations of older adult psychiatric patients. Accordingly, the goal of the current study was to examine if and how state anxiety affects major memory processes in older adults with mood disorders. <h3>Methods</h3> We analyzed cross-sectional data from 44 older adults (25 female) ranging in age from 55-82 years (mean = 66.41 ± 6.65) with diagnoses of either major depressive disorder (n=21) or bipolar spectrum disorder (n=23) who were enrolled in the Geriatric Mood Disorders Database study at McLean Hospital. State anxiety and memory were measured using the Generalized Anxiety Disorder-7 Item Scale (GAD-7) and California Verbal Learning Test (CVLT-II), respectively. Outcomes variables from the CVLT-II corresponded to three major memory processes: Encoding/registration (trial 1-5 total recall), retrieval (long delay free recall), and storage/retention (recognition accuracy). A whole-group correlational analysis (Spearman rank order) was first performed to examine associations between GAD-7 score and each memory process in the entire sample. Linear regressions were then performed separately for each CVLT-II variable using group (depression vs bipolar), GAD-7 score (mean centered), and their interaction term as predictors to determine if the relationship between group and memory performance varied as a function of state-level anxiety. <h3>Results</h3> Groups did not differ in age, sex, or years of education, though a significant group difference was seen in GAD-7 total score [Depression: 4.43 ± 4.78, Bipolar: 8.39 ± 5.70; t(42) = -2.49, p = .017]. In the whole group analysis, no significant correlations were observed between GAD-7 score and any of the CVLT-II outcomes (all ps > .15). Despite the significant group difference in GAD-7 score, regression analyses did not show significant group x GAD-7 interactions on any of the CVLT-II outcomes, nor were there any significant main effects of group or GAD-7 score on those outcomes (all ps > .10). <h3>Conclusions</h3> The current results suggest that state-level anxiety may not affect memory encoding, retrieval, or recognition in older adults with mood disorders. However, it is important to note that the current study examined only one memory measure (CVLT-II), which limited our ability to detect potential effects of state anxiety on other forms of memory (e.g., visuospatial) and other cognitive domains (e.g., attention/executive function). Similarly, the GAD-7 is a relatively brief anxiety measure that focuses on a narrower range of self-reported symptoms. Future research in this area should employ a broader range of state anxiety measures, such as functional neuroimaging and physiological measures. While this study is also limited by a somewhat modest sample size, it is nonetheless a novel contribution to the literature given the paucity of research to date on the effect of state anxiety on memory in older adults with mood disorders. It is also important to note that while our results are not significant this could provide insight into the effect a diagnosis of a mood disorder might have on resilience in older adults. If we consider the emotional growth that comes with learning how to cope with a mood disorder for many years, we could potentially see an improved ability for older adults with mood disorders to cope with their anxiety symptoms compared to those who are more recently diagnosed. This potential emotional resilience may provide a protective buffer to the threat of anxiety's impact on memory. <h3>This research was funded by</h3> This study is funded by the Rogers Family Foundation.