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Although circumstantial evidence supports enhanced Toll-like receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease1-7, evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8,9 and binds to guanosine10-12. We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10-12, and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in Tlr7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition.

Dogs are uniquely associated with human dispersal and bring transformational insight into the domestication process. Dingoes represent an intriguing case within canine evolution being geographically isolated for thousands of years. Here, we present a high-quality de novo assembly of a pure dingo (CanFam_DDS). We identified large chromosomal differences relative to the current dog reference (CanFam3.1) and confirmed no expanded pancreatic amylase gene as found in breed dogs. Phylogenetic analyses using variant pairwise matrices show that the dingo is distinct from five breed dogs with 100% bootstrap support when using Greenland wolf as the outgroup. Functionally, we observe differences in methylation patterns between the dingo and German shepherd dog genomes and differences in serum biochemistry and microbiome makeup. Our results suggest that distinct demographic and environmental conditions have shaped the dingo genome. In contrast, artificial human selection has likely shaped the genomes of domestic breed dogs after divergence from the dingo.

AIMS: In 2003, an Australian woman was convicted by a jury of smothering and killing her four children over a 10-year period. Each child died suddenly and unexpectedly during a sleep period, at ages ranging from 19 days to 18 months. In 2019 we were asked to investigate if a genetic cause could explain the children's deaths as part of an inquiry into the mother's convictions. METHODS AND RESULTS: Whole genomes or exomes of the mother and her four children were sequenced. Functional analysis of a novel CALM2 variant was performed by measuring Ca2+-binding affinity, interaction with calcium channels and channel function. We found two children had a novel calmodulin variant (CALM2 G114R) that was inherited maternally. Three genes (CALM1-3) encode identical calmodulin proteins. A variant in the corresponding residue of CALM3 (G114W) was recently reported in a child who died suddenly at age 4 and a sibling who suffered a cardiac arrest at age 5. We show that CALM2 G114R impairs calmodulin's ability to bind calcium and regulate two pivotal calcium channels (CaV1.2 and RyR2) involved in cardiac excitation contraction coupling. The deleterious effects of G114R are similar to those produced by G114W and N98S, which are considered arrhythmogenic and cause sudden cardiac death in children. CONCLUSION: A novel functional calmodulin variant (G114R) predicted to cause idiopathic ventricular fibrillation, catecholaminergic polymorphic ventricular tachycardia, or mild long QT syndrome was present in two children. A fatal arrhythmic event may have been triggered by their intercurrent infections. Thus, calmodulinopathy emerges as a reasonable explanation for a natural cause of their deaths.

Population genomic approaches can characterize dispersal across a single generation through to many generations in the past, bridging the gap between individual movement and intergenerational gene flow. These approaches are particularly useful when investigating dispersal in recently altered systems, where they provide a way of inferring long-distance dispersal between newly established populations and their interactions with existing populations. Human-mediated biological invasions represent such altered systems which can be investigated with appropriate study designs and analyses. Here we apply temporally restricted sampling and a range of population genomic approaches to investigate dispersal in a 2004 invasion of Aedes albopictus (the Asian tiger mosquito) in the Torres Strait Islands (TSI) of Australia. We sampled mosquitoes from 13 TSI villages simultaneously and genotyped 373 mosquitoes at genome-wide single nucleotide polymorphisms (SNPs): 331 from the TSI, 36 from Papua New Guinea (PNG) and four incursive mosquitoes detected in uninvaded regions. Within villages, spatial genetic structure varied substantially but overall displayed isolation by distance and a neighbourhood size of 232-577. Close kin dyads revealed recent movement between islands 31-203 km apart, and deep learning inferences showed incursive Ae. albopictus had travelled to uninvaded regions from both adjacent and nonadjacent islands. Private alleles and a co-ancestry matrix indicated direct gene flow from PNG into nearby islands. Outlier analyses also detected four linked alleles introgressed from PNG, with the alleles surrounding 12 resistance-associated cytochrome P450 genes. By treating dispersal as both an intergenerational process and a set of discrete events, we describe a highly interconnected invasive system.

The distinct properties of allo-reactive T-cell repertoires are not well understood. To investigate whether auto-reactive and allo-reactive T-cell repertoires encoded distinct properties, we used dextramer enumeration, enrichment, single-cell T-cell receptor (TCR) sequencing and multiparameter analysis. We found auto-reactive and allo-reactive T-cells differed in mean ex vivo frequency which was antigen dependent. Allo-reactive T-cells showed clear differences in TCR architecture, with enriched usage of specific T-cell receptor variable (TRBJ) genes and broader use of T-cell receptor variable joining (TRBJ) genes. Auto-reactive T-cell repertoires exhibited complementary determining regions three (CDR3) lengths using a Gaussian distribution whereas allo-reactive T-cell repertoires exhibited distorted patterns in CDR3 length. CDR3 loops from allo-reactive T-cells showed distinct physical-chemical properties, tending to encode loops that were more acidic in charge. Allo-reactive T-cell repertoires differed in diversity metrics, tending to show increased overall diversity and increased homogeneity between repertoires. Motif analysis of CDR3 loops showed allo-reactive T-cell repertoires differed in motif preference which included broader motif use. Collectively, these data conclude that allo-reactive T-cell repertoires are indeed different to auto-reactive repertoires and provide tangible metrics for further investigations and validation. Given that the antigens studied here are overexpressed on multiple cancers and that allo-reactive TCRs often show increased ligand affinity, this new TCR bank also has translational potential for adoptive cell therapy, soluble TCR-based therapy and rational TCR design.

Genetic signatures caused by demographic and adaptive processes during past climatic shifts can inform predictions of species’ responses to anthropogenic climate change. To identify these signatures in Acropora tenuis, a reef-building coral threatened by global warming, we first assembled the genome from long reads and then used shallow whole-genome resequencing of 150 colonies from the central inshore Great Barrier Reef to inform population genomic analyses. We identify population structure in the host that reflects a Pleistocene split, whereas photosymbiont differences between reefs most likely reflect contemporary (Holocene) conditions. Signatures of selection in the host were associated with genes linked to diverse processes including osmotic regulation, skeletal development, and the establishment and maintenance of symbiosis. Our results suggest that adaptation to post-glacial climate change in A. tenuis has involved selection on many genes, while differences in symbiont specificity between reefs appear to be unrelated to host population structure.

Systemic lupus erythematosus (SLE) is the prototypic systemic autoimmune disease. It is thought that many common variant gene loci of weak effect act additively to predispose to common autoimmune diseases, while the contribution of rare variants remains unclear. Here we describe that rare coding variants in lupus-risk genes are present in most SLE patients and healthy controls. We demonstrate the functional consequences of rare and low frequency missense variants in the interacting proteins BLK and BANK1, which are present alone, or in combination, in a substantial proportion of lupus patients. The rare variants found in patients, but not those found exclusively in controls, impair suppression of IRF5 and type-I IFN in human B cell lines and increase pathogenic lymphocytes in lupus-prone mice. Thus, rare gene variants are common in SLE and likely contribute to genetic risk.

Motivation: Increasingly, cost-effective high-throughput DNA sequencing technologies are being utilized to sequence human pedigrees to elucidate the genetic cause of a wide variety of human diseases. While numerous tools exist for variant prioritization within a single genome, the ability to concurrently analyze variants within pedigrees remains a challenge, especially should there be no prior indication of the underlying genetic cause of the disease. Here, we present a tool, variant analysis of sequenced pedigrees (VASP), a flexible data integration environment capable of producing a summary of pedigree variation, providing relevant information such as compound heterozygosity, genome phasing and disease inheritance patterns. Designed to aggregate data across a sequenced pedigree, VASP allows both powerful filtering and custom prioritization of both single nucleotide variants (SNVs) and small indels. Hence, clinical and research users with prior knowledge of a disease are able to dramatically reduce the variant search space based on a wide variety of custom prioritization criteria.

Druggable proteins required for B lymphocyte survival and immune responses are an emerging source of new treatments for autoimmunity and lymphoid malignancy. In this study, we show that mice with an inactivating mutation in the intramembrane protease signal peptide peptidase-like 2A (SPPL2A) unexpectedly exhibit profound humoral immunodeficiency and lack mature B cell subsets, mirroring deficiency of the cytokine B cell-activating factor (BAFF). Accumulation of Sppl2a-deficient B cells was rescued by overexpression of the BAFF-induced survival protein B cell lymphoma 2 (BCL2) but not BAFF and was distinguished by low surface BAFF receptor and IgM and IgD B cell receptors. CD8-negative dendritic cells were also greatly decreased. SPPL2A deficiency blocked the proteolytic processing of CD74 MHC II invariant chain in both cell types, causing dramatic build-up of the p8 product of Cathepsin S and interfering with earlier steps in CD74 endosomal retention and processing. The findings illuminate an important role for the final step in the CD74-MHC II pathway and a new target for protease inhibitor treatment of B cell diseases.

Results are presented from the administration of a battery of twenty- two tests to 76 Air Force weather forecasters who constituted criterion groups of 'good' and 'poor' forecasters selected by the use of the nominating technique. Five potential predictors were identified.

The report distinguishes four different connotations of 'uncertainty' as the term has been used in the psychological literature.

The earth and its atmosphere provide a highly complex environment for the propagation of electromagnetic waves. A convenient method to study the interply between this environment and propagating electromagnetic signals is to isolate various quasi-homogeneous regions of the earth-atmosphere system, and study the effects they have on different frequency signals. The troposphere, the ionosphere, the oceans and the solid crust are such quasi-homogeneous subdivisions. This report presents a short review of the physical make-up of each of the subdivisions important to radio propagation, together with the most important effects each has upon the propagation of electromagnetic signals.

This report presents a concrete realization of an admissible probability measurement procedure utilizing a computer-driven scope and light pen. This particular technique is appropriate for all multiple-choice type of testing. Empirical results are reported from an analogous pencil-and-paper realization of the same admissible probability measurement procedure. These results indicate a marked superiority for admissible probability measurement over traditional multiple-choice testing. It is suggested that further gains can be obtained by using admissible probability measurement procedures to sequentially test the scope of knowledge of a student.

Advantageous definitions of Value Engineering (VE), the 'System Approach' (SA), System Value Engineering (SVE), the Value Engineering Functional Cost Analysis (VEFCA), and Traditional Cost Analysis (TCA) are given to simplify discussion and communications and stress the specific actions required to optimize the value of military systems. Value decision making is also covered.

The effects of context on the recall and recognition of words in that context were investigated under a variety of constraints. Results indicate that the recall of a particular word in a sentence when the sentence is presented for a second time with that word omitted is a direct function of the probability of the word occurring within the context, regardless of the word-frequency in the language; (2) recognition of a particular word in a sentence is not influenced by the probability of the word occurring within the context; (3) in recognition there is a strong response bias to identify a word as having previously occurred when long series of material are shown; (4) in both recall and recognition there is a highly significant relationship between the confidence which is assigned to the response and the correctness of that response. The results are discussed in terms of retrieval of material from memory as involving a search process.

This paper highlights the organization of a creative technology-- System Engineering Management. A new Air Force Systems Command Manual describes the importance of TOTAL SYSTEM DESIGN, in which it is recognized that the successful design of a complex military system is fundamentally dependent upon the complementary interplay between all the technical/ managerial/support specialists and disciplies. The procedures summarized herein are the engineering management standard for all future system acquisition programs and projects by the Air Force.

The purpose of this study was to demonstrate that with judicious selection of stimulus material, evidence can be gathered to support either an incremental learning position or an all-or-none position. It is shown that if the a priori response probabilities of words in a series are high, the retrieval of that series from memory will lend support to the all-or-none point of view. If, on the other hand, the a priori probabilities are low, the incremental position will be upheld. It is concluded that learning is incremental, but that high response probability will tend to mack the supporting evidence.

Eleven Os were required to judge which of 4 temporal intervals contained a visual signal, in an experiment involving a total of 10,900 trials. Under some conditions, potentially useful time information was conveyed by accompanying sound stimulation, while it was lacking under others. Highest detectability of the signal was associated with an acoustic condition having white noise bursts coincident with each observation interval. Those detection scores were significantly superior to a 'reciprocal' condition having the identical amount of acoustic time-specification information. Detection was poorest under continuous noise and silence, which were not discernably different in their effects. Simple time cueing was inferred not to provide an adequate explanation for the results., Pub. in Journal of Experimental Psychology v70 n3 p332-333 1965 (Copies not available to DDC or Clearinghouse customers).

The paper describes the overall Air Force project that has been established to evolve a series of techniques for the acquisition and design control of computer programs and computer program data. The Air Force 375 System Management Concept proved to be the best model about which to structure and develop the technology and management process for computer program acquisition and development. To date, certain standards and techniques have been developed; namely, the concept of uniform specifications, design baseline management, design change controls, specification maintenance, and design accounting. Current studies are in progress to evolve computer program testing and validation standards, the systems engineering integration aspects, and the detailing of the generalized procedures and events as related to computer- oriented systems and programs., Prepared for presentation at the Spring Joint Computer Conference (1967), at Atlantic City, NJ., Apr 1967.

Literature is surveyed briefly which reported the effect upon hearing of varying the onset of a light relative to the onset of a tone. Four forced- choice experiments involving approximately 32,000 trials of the four-alternative type are reported whose results show both similarities and differences when compared with earlier experiments which did not use forced-choice. Tentative conclusions derived from all the experiments described also take into account the effect of cessation of the light relative to the tone.

The paper presents a discussion of a specific information system, the Advanced Data Management (ADAM) system, which was established to help the designers and users of large computer-centered data-base systems. The historical background of information systems is included to provide a foundation for discussing the concepts and techniques of ADAM. An application of the ADAM system to a real problem is presented to illustrate the usefulness and practicability of the ADAM design philosophy. The main point which the authors wish to establish is that computer-centered data-base systems as exemplified by ADAM provide a useful and more advanced philosophy concerning data-base systems development than currently exists.

Four questions were investigated. (1) Is the learning rate enhanced if disconnected words are presented visually in clusters, e.g., pairs of quadruples, rather than individually and successively. (2) If changes do occur, and in a lawful fashion, can such differences be accounted for adequately in terms of the development of differential interitem association strengths as a function of such stimulus arrangement. (3) What differences, if any, become evident in freerecall serial position curves by such organization. (4) How is the order of responding affected by clustering. It was found that clusetering will enhance learning rate, but that the limits are extremely restricted. It was revealed that such stimulus arrangements do affect the build-up of differential interitem association strengths, but this again is within the limits alluded to above. Apparently, differential associative strengths developed by clustering markedly affect the shapes of the serial position curves for the different groups. Clustering affects the strategy an individual adopts in responding. Such became evident in the typically different orders of responding for the various conditions.

The experiment concerned an aspect of short-term memory somewhat neglected in the past, namely, the ability to remember, i.e., to recognize, complex meaningful visual configurations. S's task was to inspect an extended sequence of photographs of assorted content and to identify those which were occurring for the second time within the sequence. The probability of recognizing the recurrence of a photo as such was very high even with as many as 200 items intervening between its first and second occurrence., Pub. in Canadian Journal of Psychology v19 n2 p155-60, 1965

This paper describes an effort to adapt the AFSCM375 series and AFSCM310 series management techniques to computer program acquisition. These techniques are unique in that they provide the first standardized management approach to computer program design and development. A complete process of management procedures that has been developed for management of computer programs during definition and acquisition phases is discussed. Particular emphasis is placed on an extensive change package to AFSCM 375-1 Configuration Management During Definition and Acquisition Phases and a package of computer program data items for insertion in AFSCM/AFLCM 310-1 Data Management proposed by Electronic Systems Division of AFSC. The concepts of uniform specifications, baseline management, change control, specification maintenance and accounting and standard data items as they apply to computer programs are discussed and the impact of applying these techniques to System Programs is analyzed.

An investigation was undertaken to provide a human factors evaluation of an electroluminescent display designed for the presentation of around-the-base weather messages. Time and error data were obtained for 42 Air Force weather, GCA, and pilot personnel in responding to six questions for each of 50 weather messages, 25 of which were presented on an electroluminescent display and 25 by conventional teletype format. The few significant differences found do not warrant a conclusion that the electrolumescent format employed is inferior to the conventional teletype format. It is concluded that weather message information processing may be improved by the development of time and error normative data for a standard set of weather messages, thereby permitting the identification of high-error (perhaps error-prone) personnel, by training to improve the interpretation of visibility coding and more specifically, by an improved formating of fractions concerned with visibility. The suggestion for the development of normative data may have applicability for other military information systems.

A passive environmental sensor was evaluated as an input device capable of presenting tactile data to a human. The experiment provided information on the ability of the human to detect differences within the range of the vibratory transducer. Frequency discrimination thresholds showed wide differences between subjects and a significant increase in human sensitivity at one point of the frequency input levels. This increases sensitivity was explained in terms of the resonant frequency of the vibratory and also in terms of the generally known high human sensitivity for amplitude and frequency changes at 200-300 cps. It was concluded that for fine-grain data discrimination individual differences may influence the final design of the sensor. However, these differences may be reduced and the sensitivity of the user improved if its electronic design and its transducers provide redundancy to the human.

The paper presents Air Force developed concepts for technical control and design verification of computer programs. Starting with the definition of a computer as a deliverable contract end item requiring a design and development effort, management procedures for controlling the design and development process are explained. Technical control of computer program design through periodic design reviews is outlined and test concepts for verification of computer program performance are presented. The techniques discussed are based on an exchange of technical information between the contractor and the procuring agency at a series of discrete milestones throughout the design and development process. The milestones, including design reviews, qualification testing, etc., are described and the relationship of these milestones to the design and development of a computer-based system is illustrated. The techniques are directly applicable to any large computer-based system whether it be military or commercial and they can be easily tailored to fit a small computer system.

The problem of estimating the accuracy of ones own recollections was investigated in four experiments under a variety of conditions. Subjects were shown a series of paired words; then they were shown the first member of the pairs and asked to recall the second member of each. Along with each attempt at recall the subjects were asked to give a confidence rating on a scale from 1 to 5. In all, 180 subjects were tested for a total 11,200 trials. The confidence results are highly significant, indicating that subjects were able to discriminate their correct recollections from mere guesses. Comparisons are presented showing how realism of confidence varies over the main experimental treatments: variations in meaningfulness of material, one versus two exposures to paired-associate lists, and presence of varying amounts of irrelevant material in the acquisition lists.

The report compares two types of classroom testing in terms of efficacy in guiding instruction. One type of testing is the traditional indirect method based on the observation of choices. The other type is the direct method based on admissible probability measurement. The general finding is that the direct methods always perform as well as and in most cases better than the indirect methods. This deficiency in the indirect method can be alleviated in theory by introducing redundancy into the test and asking the same question over and over again. The performance of indirect methods depends in a very critical manner upon the information available to the instructor from other sources about the current state of knowledge of each student. The performance of the direct methods is unaffected by this. The gain in effectiveness achieved by using direct methods must be balanced off against the cost of using these new methods. A direct method may require more student time per item than does an indirect method. This, however, may be more than compensated for by the requirement for redundancy when using the indirect method. In addition, since a direct method does not require additional information from the instructor as to the current state of knowledge of each student, the possibility exists that much larger classes may be taught with no loss in effectiveness thus implying even further economic benefits from the use of direct methods to guide classroom instruction.

This study was designed to discover whether query and message items are equivalent in their effect on short-term memory in situations where a person is required to process a sequence of messages while concurrently processing queries about them. It was assumed that recall is consistently degraded as the number of items interpolated between a message and its subsequent query increases. It was hypothesized that this degradation is greater for those subsequences with interpolated queries than for those containing messages only. The results showed that interpolated queries do degrade recall significantly more than do messages.

This study showed no trends between reaction time and interstimulus intervals and reaction time and time blocks under knowledge of results or no knowledge of results. An ABC X S variance design of reaction time scores showed only knowledge of results by Ss was statistically reliable. The source of this variance was attributed to sex differences. Results showed that under knowledge of results fast mean reaction time (males) was associated with high skin conductance. For females slow mean reaction time was associated with low conductance. Under the no knowledge of results condition, females showed slower mean reaction time than males. Their conductance scores showed significantly greater variability without knowledge of results than under the knowledge condition. Males under no knowledge show mean conductance scores as high as those under knowledge of results. However, their mean reaction time scores under the no knowledge condition was significantly lower than under knowledge of results. It was concluded that males, contrasted with females, respond differentially to knowledge and no knowledge of results in simple reaction time studies. As males show high conductance and females high variability in conductance under no knowledge of results, an inhibition-reinforcement theory for vigilance tasks appears inadequate.

Recent experience at ESD in acquiring complex computer based systems has identified a deficiency in existing systems management techniques in the area of computer programs. The systems management techniques generally in use were designed for 'equipment' systems and need to be expanded to include computer programs. This paper describes an ESD approach to adapting existing AFSC system management techniques to computer programs. Procedures for insuring system compatibility, design integrity and technical control are discussed and a method for achieving design verification and qualification is presented. Particular emphasis is placed on the relationship of these techniques to computer programs as elements of large computer based systems. The application of these techniques is illustrated through selected examples taken from current ESD system procurements.

This report summarizes the activities of the Decision Sciences Laboratory and describes achievements, progress, and results obtained by the Laboratory scientists in the past two years.

Application of Configuration Management Exhibits on ESD Programs has indicated that the terminology contained within them can be subject to interpretation. This report identifies problem areas that required clarification and workable approaches taken that were considered to be in accordance with the intent of AFSCM 375-1., See also N65-19789.

Experience at ESD in the application of AFSCM 375-1, Configuration Management During Definition and Acquisition Phases, to electronic systems/ projects identified a deficiency in the area of computer programs. Attempts to apply the manual to the computer segment of a computer-based system showed that techniques to handle the computer programs portion were lacking. Techniques and procedures developed for the application of configuration management to computer programs were developed and published as ESD Exhibit EST-1 to augment the basic manual. This paper presents the concepts embodied in the exhibit and describes a program for establishing, monitoring and updating a configuration management system for computer programs acquired as part of an Air Force system.

A 4-alternative forced-choice test was administered to 96 Ss. S's task was to attempt to select the correct alternative from each test item and to indicate his degree of confidence in his choice on a 5-point rating scale. The objective was to compare the confidence assignments of Ss who did relatively well on the primary judgmental task with those of Ss who did poorly. It was found that Ss who performed poorly on the primary task (LP Ss) tended on the average to use lower confidence ratings than Ss who did relatively well (HP Ss). Although few used either high or low ratings exclusively, all Ss tended to use one end of the confidence scale much more frequently than the other. However, whereas HP Ss were fairly consistent in using the high end of the scale, LP Ss were about evenly divided between those using the high end and those using the low. For both groups, performance tended to be monotonically related to expressed confidence. In terms of measures developed by Adams and Adams, HP Ss made more 'realistic' confidence judgments than did LP Ss; however, there was no striking difference between groups in terms of differences in performance associated with step increases in expressed confidence., Published in Perceptual and Motor Skills, v20 p311-316, 1965.

Performance measures from the first major experiment in a series on tactical decision-making for treat evaluation and action selection in aero space surveillance are described. Two groups of experimental commanders performed under several levels of target track load and threat complexity conditions. The task of the commanders was: (1) to minimize damage to the weapon areas, (2) to destroy a maximum number of threatening vehicles, (3) to conserve counter weapons so as to consume a minimum of forces consistent with objectives (1) and (2) above, and (4) to develop his own strategy under constraints imposed by the ground rules. In order to provide some standard performance criteria, a sample of the experimental problems was solved analytically so as to re present both 'good' and 'poor' automated decision making and 'idealized' or maximum human performance. Human empirical scores compared favorably with analytical performance measures. Human empirical performance continuously improved as a function of number of system runs., In cooperation with Detection Physics Lab., Air Force Cambridge Research Labs., Bedford, Mass.

Word-intelligibility (psycho-acoustic), Articulation Index (electrical) and voice recognition tests were made on the Thule, Greenland, to Cape Dyer, Baffin Island, link of the DEWDROP tropos pheric-scatter communication system, and on the Gander, Newfoundland, to Harmon Air Force Base, Newfoundland, link of the POLEVAULT tropospheric scatter communication system, and compared against similar tests taken on a laboratory reference system. Harvard phonetically-balanced (PB) word-lists were used in the psycho-acoustic tests; an abbreviated octave-band form of the Articulation Index procedure (after Kryter) was the basis of the electrical tests. These two measures agreed in ranking the three systems in order of intelligibility from highest to lowest: laboratory, POLEVAULT and DEWDROP. It is concluded that the Articulation Index technique suitably modified, is feasibile and useful for voice-system performancuation and quality control testing. It is also concluded, tentatively, that system characteristics affecting intelligibility do not necessarily affect listeners' ability to recognize individual talkers.

The report is a general review of the Scientific and Technical Information Program. It was written primarily as a working guide for technical personnel producing or monitoring technical reports and STINFO Officers at the SPO and laboratory level. The report includes Department of Defense, Air Force and Air Force Systems Command policies, regulations and information sources; publication of reports; and release and distribution of reports.