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Rationale: The airway microbiome has the potential to shape chronic obstructive pulmonary disease (COPD) pathogenesis, but its relationship to outcomes in milder disease is unestablished. Objectives: To identify sputum microbiome characteristics associated with markers of COPD in participants of the Subpopulations and Intermediate Outcome Measures of COPD Study (SPIROMICS). Methods: Sputum DNA from 877 participants was analyzed using 16S ribosomal RNA gene sequencing. Relationships between baseline airway microbiota composition and clinical, radiographic, and mucoinflammatory markers, including longitudinal lung function trajectory, were examined. Measurements and Main Results: Participant data represented predominantly milder disease (Global Initiative for Chronic Obstructive Lung Disease stage 0-2 obstruction in 732 of 877 participants). Phylogenetic diversity (i.e., range of different species within a sample) correlated positively with baseline lung function, decreased with higher Global Initiative for Chronic Obstructive Lung Disease stage, and correlated negatively with symptom burden, radiographic markers of airway disease, and total mucin concentrations ( P  < 0.001). In covariate-adjusted regression models, organisms robustly associated with better lung function included Alloprevotella , Oribacterium , and Veillonella species. Conversely, lower lung function, greater symptoms, and radiographic measures of small airway disease were associated with enrichment in members of Streptococcus , Actinobacillus , Actinomyces , and other genera. Baseline sputum microbiota features were also associated with lung function trajectory during SPIROMICS follow-up (stable/improved, decline, or rapid decline groups). The stable/improved group (slope of FEV 1 regression ⩾66th percentile) had greater bacterial diversity at baseline associated with enrichment in Prevotella , Leptotrichia , and Neisseria species. In contrast, the rapid decline group (FEV 1 slope ⩽33rd percentile) had significantly lower baseline diversity associated with enrichment in Streptococcus species. Conclusions: In SPIROMICS, baseline airway microbiota features demonstrate divergent associations with better or worse COPD-related outcomes.

Background: Because chest CT scan has largely supplanted surgical lung biopsy for diagnosing most cases of interstitial lung disease (ILD), tools to standardize CT scan interpretation are urgently needed., Research Question: Does a deep learning (DL)-based classifier for usual interstitial pneumonia (UIP) derived using CT scan features accurately discriminate radiologist-determined visual UIP?, Study Design and Methods: A retrospective cohort study was performed. Chest CT scans acquired in individuals with and without ILD were drawn from a variety of public and private data sources. Using radiologist-determined visual UIP as ground truth, a convolutional neural network was used to learn discrete CT scan features of UIP, with outputs used to predict the likelihood of UIP using a linear support vector machine. Test performance characteristics were assessed in an independent performance cohort and multicenter ILD clinical cohort. Transplant-free survival was compared between UIP classification approaches using the Kaplan-Meier estimator and Cox proportional hazards regression., Results: A total of 2,907 chest CT scans were included in the training (n = 1,934), validation (n = 408), and performance (n = 565) data sets. The prevalence of radiologist-determined visual UIP was 12.4% and 37.1% in the performance and ILD clinical cohorts, respectively. The DL-based UIP classifier predicted visual UIP in the performance cohort with sensitivity and specificity of 93% and 86%, respectively, and in the multicenter ILD clinical cohort with 81% and 77%, respectively. DL-based and visual UIP classification similarly discriminated survival, and outcomes were consistent among cases with positive DL-based UIP classification irrespective of visual classification., Interpretation: A DL-based classifier for UIP demonstrated good test performance across a wide range of UIP prevalence and similarly discriminated survival when compared with radiologist-determined UIP. This automated tool could efficiently screen for UIP in patients undergoing chest CT scan and identify a high-risk phenotype among those with known ILD., Competing Interests: Financial/Nonfinancial Disclosures The authors have reported to CHEST the following: L. K., K. L., S. Z., and C. H. are employees of Imbio, Inc. H. G., E. S., S. L., and C. S. are paid consultants for Imbio, Inc. J. H. C., A. A., and J. M. O. report consulting fees from Genentech unrelated to this investigation. None declared (L. C., J. V. P., J. M. W., A. W. M., S. G., A. G.)., (Copyright © 2023 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to train and validate machine learning models for predicting rapid decline of forced expiratory volume in 1 s (FEV 1 ) in individuals with a smoking history at-risk-for chronic obstructive pulmonary disease (COPD), Global Initiative for Chronic Obstructive Lung Disease (GOLD 0), or with mild-to-moderate (GOLD 1-2) COPD. We trained multiple models to predict rapid FEV 1 decline using demographic, clinical and radiologic biomarker data. Training and internal validation data were obtained from the COPDGene study and prediction models were validated against the SPIROMICS cohort. Methods: We used GOLD 0-2 participants ( n = 3,821) from COPDGene (60.0 ± 8.8 years, 49.9% male) for variable selection and model training. Accelerated lung function decline was defined as a mean drop in FEV 1 % predicted of > 1.5%/year at 5-year follow-up. We built logistic regression models predicting accelerated decline based on 22 chest CT imaging biomarker, pulmonary function, symptom, and demographic features. Models were validated using n = 885 SPIROMICS subjects (63.6 ± 8.6 years, 47.8% male). Results: The most important variables for predicting FEV 1 decline in GOLD 0 participants were bronchodilator responsiveness (BDR), post bronchodilator FEV 1 % predicted (FEV 1 .pp.post), and CT-derived expiratory lung volume; among GOLD 1 and 2 subjects, they were BDR, age, and PRM lower lobes fSAD . In the validation cohort, GOLD 0 and GOLD 1-2 full variable models had significant predictive performance with AUCs of 0.620 ± 0.081 ( p = 0.041) and 0.640 ± 0.059 ( p < 0.001). Subjects with higher model-derived risk scores had significantly greater odds of FEV 1 decline than those with lower scores. Conclusion: Predicting FEV 1 decline in at-risk patients remains challenging but a combination of clinical, physiologic and imaging variables provided the best performance across two COPD cohorts., Competing Interests: WL reports personal fees from Konica Minolta and Continuing Education Alliance. JC reports grants from NHLBI and the COPD Foundation, during performance of this study; grants from NHLBI, NIAID, the Department of Veterans Affairs, and the Department of Defense, outside this study; consulting fees (paid to his institution) from AstraZeneca PLC and CLS Behring, LLC, outside this study; and personal fees from AstraZeneca Global, outside this study. CG is co-inventor of Parametric Response Mapping, which the University of Michigan has licensed to Imbio, LLC., and has a financial interest in Imbio, LLC. MH reports personal fees from GlaxoSmithKline, AstraZeneca, Boehringer Ingelheim, Cipla, Chiesi, Novartis, Pulmonx, Teva, Verona, Merck, Mylan, Sanofi, DevPro, Aerogen, Polarian, Regeneron, Amgen, UpToDate, Altesa Biopharma, Medscape, NACE, MDBriefcase and Integrity. She has received either in kind research support or funds paid to the institution from the NIH, Novartis, Sunovion, Nuvaira, Sanofi, AstraZeneca, Boehringer Ingelheim, Gala Therapeutics, Biodesix, the COPD Foundation and the American Lung Association. She has participated in Data Safety Monitoring Boards for Novartis and Medtronic with funds paid to the institution. She has received stock options from Meissa Vaccines and Altesa Biopharma. CH is employed by and has stock options in Imbio, Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Labaki, Murray, Martinez, Curtis, Hoffman, Ram, Bell, Galban, Han and Hatt.)

Multiparameter quantitative imaging incorporates anatomical, functional, and/or behavioral biomarkers to characterize tissue, detect disease, identify phenotypes, define longitudinal change, or predict outcome. Multiple imaging parameters are sometimes considered separately but ideally are evaluated collectively. Often, they are transformed as Likert interpretations, ignoring the correlations of quantitative properties that may result in better reproducibility or outcome prediction. In this paper we present three use cases of multiparameter quantitative imaging: i) multidimensional descriptor, ii) phenotype classification, and iii) risk prediction. A fourth application based on data-driven markers from radiomics is also presented. We describe the technical performance characteristics and their metrics common to all use cases, and provide a structure for the development, estimation, and testing of multiparameter quantitative imaging. This paper serves as an overview for a series of individual articles on the four applications, providing the statistical framework for multiparameter imaging applications in medicine., (Copyright © 2022 The Association of University Radiologists. All rights reserved.)

As the COVID-19 pandemic impacts global populations, computed tomography (CT) lung imaging is being used in many countries to help manage patient care as well as to rapidly identify potentially useful quantitative COVID-19 CT imaging biomarkers. Quantitative COVID-19 CT imaging applications, typically based on computer vision modeling and artificial intelligence algorithms, include the potential for better methods to assess COVID-19 extent and severity, assist with differential diagnosis of COVID-19 versus other respiratory conditions, and predict disease trajectory. To help accelerate the development of robust quantitative imaging algorithms and tools, it is critical that CT imaging is obtained following best practices of the quantitative lung CT imaging community. Toward this end, the Radiological Society of North America's (RSNA) Quantitative Imaging Biomarkers Alliance (QIBA) CT Lung Density Profile Committee and CT Small Lung Nodule Profile Committee developed a set of best practices to guide clinical sites using quantitative imaging solutions and to accelerate the international development of quantitative CT algorithms for COVID-19. This guidance document provides quantitative CT lung imaging recommendations for COVID-19 CT imaging, including recommended CT image acquisition settings for contemporary CT scanners. Additional best practice guidance is provided on scientific publication reporting of quantitative CT imaging methods and the importance of contributing COVID-19 CT imaging datasets to open science research databases., (Copyright © 2021. Published by Elsevier Inc.)

Rationale and Objectives: Bronchiectasis (BE) is associated with chronic obstructive pulmonary disease (COPD), but emphysema and small airways disease, main pathologic features of COPD, have been sparsely studied in BE. We aimed to objectively assess those features in smokers with and without radiographic BE and examine its relationships to airflow obstruction and exercise capacity., Material and Methods: We measured emphysema and small airways disease on paired inspiratory-expiratory computed tomography (CT) scans with the parametric response map (PRM EMPH and PRM SAD ) method in 1184 smokers with and without radiographic BE. PRM SAD and PRM EMPH are expressed as the percentage of lung area. Clinical, spirometry, and exercise capacity data were measured with standardized methods. The differences in PRM SAD and PRM EMPH between subjects with and without radiographic BE were assessed using multivariable linear regression analysis, and their associations with FEV 1 and six-minute walk test (6MWT) were assessed with generalized linear models., Results: Out of 1184 subjects, 383 (32%) had radiographic BE. PRM EMPH but not PRM SAD was higher in subjects with radiographic BE than those without radiographic BE in adjusted models. Subjects with radiographic BE and PRM EMPH (defined as ≥5% on paired CTs) had lower FEV 1 (least square mean, 1479 mL vs. 2350 mL p < 0.0001) and 6MWT (372 m vs. 426 m p = 0.0007) than those with radiographic BE alone in adjusted models., Conclusion: Smokers with radiographic BE have an increased burden of emphysema on paired CTs, and those with radiographic BE and emphysema have lower airflow and exercise capacity., (Copyright © 2020 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Parametric response mapping (PRM) is a novel computed tomography (CT) technology that has shown potential for assessment of bronchiolitis obliterans syndrome (BOS) after hematopoietic stem cell transplantation (HCT). The primary aim of this study was to evaluate whether variations in image acquisition under real-world conditions affect the PRM measurements of clinically diagnosed BOS. CT scans were obtained retrospectively from 72 HCT recipients with BOS and graft-versus-host disease from Fred Hutchinson Cancer Research Center, Karolinska Institute, and the University of Michigan. Whole lung volumetric scans were performed at inspiration and expiration using site-specific acquisition and reconstruction protocols. PRM and pulmonary function measurements were assessed. Patients with moderately severe BOS at diagnosis (median forced expiratory volume at 1 second [FEV1] 53.5% predicted) had similar characteristics between sites. Variations in site-specific CT acquisition protocols had a negligible effect on the PRM-derived small airways disease (SAD), that is, BOS measurements. PRM-derived SAD was found to correlate with FEV1% predicted and FEV1/ forced vital capacity (R = -0.236, P = .046; and R = -0.689, P < .0001, respectively), which suggests that elevated levels in the PRM measurements are primarily affected by BOS airflow obstruction and not CT scan acquisition parameters. Based on these results, PRM may be applied broadly for post-HCT diagnosis and monitoring of BOS., (© 2020 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Purpose: Multiple commercial, open-source, and academic software tools exist for objective quantification of lung density in computed tomography (CT) images. The purpose of this study was to evaluate the intersoftware reproducibility of CT lung density measurements., Methods: Computed tomography images from 50 participants from the COPDGene TM cohort study were randomly selected for analysis; n = 10 participants across each global initiative for chronic obstructive lung disease (GOLD) grade (GOLD 0-IV). Academic-based groups (n = 4) and commercial vendors (n = 4) participated anonymously to generate CT lung density measurements using their software tools. Computed tomography total lung volume (TLV), percentage of the low attenuation areas in the lung with Hounsfield unit (HU) values below -950HU (LAA 950 ), and the HU value corresponding to the 15th percentile on the parenchymal density histogram (Perc15) were included in the analysis. The intersoftware bias and reproducibility coefficient (RDC) was generated with and without quality assurance (QA) for manual correction of the lung segmentation; intrasoftware bias and RDC was also generated by repeated measurements on the same images., Results: Intersoftware mean bias was within ±0.22 mL, ±0.46%, and ±0.97 HU for TLV, LAA 950 and Perc15, respectively. The RDC was 0.35 L, 1.2% and 1.8 HU for TLV, LAA 950 and Perc15, respectively. Intersoftware RDC remained unchanged following QA: 0.35 L, 1.2% and 1.8 HU for TLV, LAA 950 and Perc15, respectively. All software investigated had an intrasoftware RDC of 0. The RDC was comparable for TLV, LAA 950 and Perc15 measurements, respectively, for academic-based groups/commercial vendor-based software tools: 0.39 L/0.32 L, 1.2%/1.2%, and 1.7 HU/1.6 HU. Multivariable regression analysis showed that academic-based software tools had greater within-subject standard deviation of TLV than commercial vendors, but no significant differences between academic and commercial groups were found for LAA 950 or Perc15 measurements., Conclusions: Computed tomography total lung volume and lung density measurement bias and reproducibility was reported across eight different software tools. Bias was negligible across vendors, reproducibility was comparable for software tools generated by academic-based groups and commercial vendors, and segmentation QA had negligible impact on measurement variability between software tools. In summary, results from this study report the amount of additional measurement variability that should be accounted for when using different software tools to measure lung density longitudinally with well-standardized image acquisition protocols. However, intrasoftware reproducibility was deterministic for all cases so use of the same software tool to reduce variability for serial studies is highly recommended., (© 2020 American Association of Physicists in Medicine.)

Purpose: Pulmonary nodules, found either incidentally or on lung cancer screening, are common. Evaluating the benign or malignant nature of these nodules is costly in terms of patient risk and expense. The presence of both global and regional emphysema has been linked to increased lung cancer risk. We sought to determine whether the measurement of emphysema directly adjacent to a lung nodule could inform the likelihood of a nodule being malignant., Materials and Methods: Within a population of Veterans at high risk for lung cancer, 58 subjects with malignant nodules found on computerized tomographic chest scans were matched by lobe and nodule size to 58 controls. Lung densitometry was measured via determination of the low attenuation area percentage at -950 Hounsfield units (LAA950) and the Hounsfield unit (HU) value at which 15% of lung voxels have a lower lung density (Perc15), at predefined lung volumes that encompassed the nodule to evaluate both perinodular and regional lung fields. The association between measured lung density and malignancy was investigated using conditional logistic regression models, with densitometry measurements used as the primary predictor, adjusting for age alone, or age and computerized tomographic scan characteristics., Results: No significant differences in emphysema measurements between malignant and benign nodules were identified at lung volumes encompassing both perinodular and regional emphysema. Furthermore, emphysema quantification remained stable across lung volumes within individuals., Conclusions: In this study, quantifying the degree of perinodular or regional emphysema did not offer any benefit in the risk stratification of lung nodules.

Rationale: Evidence suggests damage to small airways is a key pathologic lesion in chronic obstructive pulmonary disease (COPD). Computed tomography densitometry has been demonstrated to identify emphysema, but no such studies have been performed linking an imaging metric to small airway abnormality. Objectives: To correlate ex vivo parametric response mapping (PRM) analysis to in vivo lung tissue measurements of patients with severe COPD treated by lung transplantation and control subjects. Methods: Resected lungs were inflated, frozen, and systematically sampled, generating 33 COPD ( n  = 11 subjects) and 22 control tissue samples ( n  = 3 subjects) for micro-computed tomography analysis of terminal bronchioles (TBs; last generation of conducting airways) and emphysema. Measurements and Main Results: PRM analysis was conducted to differentiate functional small airways disease (PRM fSAD ) from emphysema (PRM Emph ). In COPD lungs, TB numbers were reduced ( P  = 0.01); surviving TBs had increased wall area percentage ( P  < 0.001), decreased circularity ( P  < 0.001), reduced cross-sectional luminal area ( P  < 0.001), and greater airway obstruction ( P  = 0.008). COPD lungs had increased airspace size ( P  < 0.001) and decreased alveolar surface area ( P  < 0.001). Regression analyses demonstrated unique correlations between PRM fSAD and TBs, with decreased circularity ( P  < 0.001), decreased luminal area ( P  < 0.001), and complete obstruction ( P  = 0.008). PRM Emph correlated with increased airspace size ( P  < 0.001), decreased alveolar surface area ( P  = 0.003), and fewer alveolar attachments per TB ( P  = 0.01). Conclusions: PRM fSAD identifies areas of lung tissue with TB loss, luminal narrowing, and obstruction. This is the first confirmation that an imaging biomarker can identify terminal bronchial pathology in established COPD and provides a noninvasive imaging methodology to identify small airway damage in COPD.

Background and Aims: The pseudometallophyte Noccaea caerulescens is an excellent model to study evolutionary processes, as it grows both on normal and on heavy-metal-rich, toxic soils. The evolution and demography of populations are critically impacted by mating system and, yet, information about the N. caerulescens mating system is limited., Methods: Mean selfing rates were assessed using microsatellite loci and a robust estimation method (RMES) in five metallicolous and five non-metallicolous populations of N. caerulescens in Southern France, and this measure was replicated for two successive reproductive seasons. As a part of the study, the patterns of gene flow among populations were analysed. The mating system was then characterized at a fine spatial scale in three populations using the MLTR method on progeny arrays., Key Results: The results confirm that N. caerulescens has a mixed mating system, with selfing rates ranging from 0·2 to 0·5. Selfing rates did not vary much among populations within ecotypes, but were lower in the metallicolous than in the non-metallicolous ecotype, in both seasons. Effective population size was also lower in non-metallicolous populations. Biparental inbreeding was null to moderate. Differentiation among populations was generally high, but neither ecotype nor isolation by distance explained it., Conclusions: The consequences of higher selfing rates on adaptation are expected to be weak to moderate in non-metallicolous populations and they are expected to suffer less from inbreeding depression, compared to metallicolous populations., (© The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company.)

Retrotransposons are the main component of plant genomes. Recent studies have revealed the complexity of their evolutionary dynamics. Here, we have identified Copia25 in Coffea canephora, a new plant retrotransposon belonging to the Ty1-Copia superfamily. In the Coffea genomes analyzed, Copia25 is present in relatively low copy numbers and transcribed. Similarity sequence searches and PCR analyses show that this retrotransposon with LTRs (Long Terminal Repeats) is widely distributed among the Rubiaceae family and that it is also present in other distantly related species belonging to Asterids, Rosids and monocots. A particular situation is the high sequence identity found between the Copia25 sequences of Musa, a monocot, and Ixora, a dicot species (Rubiaceae). Our results reveal the complexity of the evolutionary dynamics of the ancient element Copia25 in angiosperm, involving several processes including sequence conservation, rapid turnover, stochastic losses and horizontal transfer.

Hypothesis testing on signals defined on surfaces (such as the cortical surface) is a fundamental component of a variety of studies in Neuroscience. The goal here is to identify regions that exhibit changes as a function of the clinical condition under study. As the clinical questions of interest move towards identifying very early signs of diseases, the corresponding statistical differences at the group level invariably become weaker and increasingly hard to identify. Indeed, after a multiple comparisons correction is adopted (to account for correlated statistical tests over all surface points), very few regions may survive. In contrast to hypothesis tests on point-wise measurements, in this paper, we make the case for performing statistical analysis on multi-scale shape descriptors that characterize the local topological context of the signal around each surface vertex. Our descriptors are based on recent results from harmonic analysis, that show how wavelet theory extends to non-Euclidean settings (i.e., irregular weighted graphs). We provide strong evidence that these descriptors successfully pick up group-wise differences, where traditional methods either fail or yield unsatisfactory results. Other than this primary application, we show how the framework allows performing cortical surface smoothing in the native space without mappint to a unit sphere.

This paper describes a clinically translatable interventional guidance platform to improve the accuracy and precision of stem cell injections into a beating heart. The proposed platform overlays live position of an injection catheter onto a fusion of a pre-procedural MR roadmap with real-time 3D transesophageal echocardiography (TEE). Electromagnetic (EM) tracking is used to initialize the fusion. The fusion is intra-operatively compensated for respiratory motion using a novel algorithm that uses peri-operative full volume ultrasound images. Validation of the system on a moving heart phantom produced a landmark registration accuracy of 2.8 +/- 1.45mm. Validation on animal in vivo data produced an average registration accuracy of 2.2 +/- 1.8 mm; indicating that it is feasible to reliably and robustly fuse the MR road-map with catheter position using 3D ultrasound in a clinical setting.

To determine the reliability, stability, validity and precision of a stereophotogrammetry (SP) system for use in quantifying the complex three-dimensional structure of the human torso, we performed assessments of the system using images of geometric solids and a human-form mannequin. Analysis of geometric solids revealed excellent intra- and interrater reliability of the system for linear, surface area and volume measurements (r>0.99, P<0.001). Overall, no significant difference was found between SP and manual measurements (F=4.23, P>0.06). The system exhibited excellent stability in images of the mannequin over time (r>0.99). The limit of precision (error>5%) of the system to detect objects on the surface of the mannequin was estimated at an object size of 23.5cm(2) for surface area and 32mL for volume. These results demonstrate the capability of SP of the torso to be used as a reliable, stable and valid measure of torso morphology to be applied as a clinical outcome tool in studies of bony and soft tissue pathologies such as scoliosis, rib deformities, obesity or edema.

The mechanism by which the contractile machinery of muscle is assembled and maintained is not well-understood. Members of the cysteine-rich protein (CRP) family have been implicated in these processes. Three vertebrate CRPs (CRP1-3) that exhibit developmentally regulated muscle-specific expression have been identified. All three proteins are associated with the actin cytoskeleton, and one has been shown to be required for striated muscle structure and function. The vertebrate CRPs identified to date display a similar molecular architecture; each protein is comprised of two tandemly arrayed LIM domains, protein-binding motifs found in a number of proteins with roles in cell differentiation. Each LIM domain coordinates two Zn(II) ions that are bound independently in CCHC (C=Cys, H=His) and CCCC modules. Here we describe the solution structure of chicken CRP1 determined by homonuclear and 1H-15N heteronuclear magnetic resonance spectroscopy. Comparison of the structures of the two LIM domains of CRP1 reveals a high degree of similarity in their tertiary folds. In addition, the two component LIM domains represent two completely independent folding units and exhibit no apparent interactions with each other. The structural independence and spatial separation of the two LIM domains of CRP1 are compatible with an adapter or linker role for the protein.

Chlamydia trachomatis serovar L1/440/LN possesses a 7498bp plasmid which was designated pLGV440. The plasmid was cloned at the BamH1 site of pAT153 into Escherichia coli and the recombinant plasmid was designated pCTL1. A detailed restriction endonuclease map of pCTL1 was constructed. A fragment of the chlamydial plasmid was shown to function as a promoter in E. coli when placed upstream of the lacZ gene. The entire plasmid was sequenced by the chain termination method. Open reading frames were identified from the resulting consensus sequence together with a candidate for the plasmid origin of replication consisting of four perfect tandem repeats of a 22bp sequence, an A:T rich sequence and an open reading frame which could generate a 34.8kdal product. The predicted polypeptide products of the open reading frames were compared by computer with all reported protein sequences. Homology of the predicted polypeptide product of an open reading frame to the E. coli dnaB protein and the analogous product of gene 12 of bacteriophage P22 is described.

Effects of learning names for random nonsense shapes prior to a probe-type serial-recall task were investigated in disabled readers. 33 10-yr.-old, right-handed boys were subjects in a 3 (reading groups) X 2 (training conditions) X 6 (serial positions) repeated-measures, split-plot level analysis of covariance design. No differences among reading groups on recall strength or primary recall were found, suggesting similar verbal skills. Deficiencies in verbal mediation did not appear to account for the reading disability of these subgroups.