First Measurement of Discrimination between Helium and Electron Recoils in Liquid Xenon for Low-Mass Dark Matter Searches

We report the first measurement of discrimination between low-energy helium recoils and electron recoils in liquid xenon. This result is relevant to proposed low-mass dark matter searches which seek to dissolve light target nuclei in the active volume of liquid-xenon time projection chambers. Low-energy helium recoils were produced by degrading α particles from ^{210}Po with a gold foil situated on the cathode of a liquid xenon time-projection chamber. The resulting population of helium recoil events is well separated from electron recoils and is also offset from the expected position of xenon nuclear recoil events.

Operational Ontology for Oncology (O3): A Professional Society-Based, Multistakeholder, Consensus-Driven Informatics Standard Supporting Clinical and Research Use of Real-World Data From Patients Treated for Cancer

PURPOSE

The ongoing lack of data standardization severely undermines the potential for automated learning from the vast amount of information routinely archived in electronic health records (EHRs), radiation oncology information systems, treatment planning systems, and other cancer care and outcomes databases. We sought to create a standardized ontology for clinical data, social determinants of health, and other radiation oncology concepts and interrelationships.

METHODS AND MATERIALS

The American Association of Physicists in Medicine's Big Data Science Committee was initiated in July 2019 to explore common ground from the stakeholders' collective experience of issues that typically compromise the formation of large inter- and intra-institutional databases from EHRs. The Big Data Science Committee adopted an iterative, cyclical approach to engaging stakeholders beyond its membership to optimize the integration of diverse perspectives from the community.

RESULTS

We developed the Operational Ontology for Oncology (O3), which identified 42 key elements, 359 attributes, 144 value sets, and 155 relationships ranked in relative importance of clinical significance, likelihood of availability in EHRs, and the ability to modify routine clinical processes to permit aggregation. Recommendations are provided for best use and development of the O3 to 4 constituencies: device manufacturers, centers of clinical care, researchers, and professional societies.

CONCLUSIONS

O3 is designed to extend and interoperate with existing global infrastructure and data science standards. The implementation of these recommendations will lower the barriers for aggregation of information that could be used to create large, representative, findable, accessible, interoperable, and reusable data sets to support the scientific objectives of grant programs. The construction of comprehensive "real-world" data sets and application of advanced analytical techniques, including artificial intelligence, holds the potential to revolutionize patient management and improve outcomes by leveraging increased access to information derived from larger, more representative data sets.

First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Study of dielectric breakdown in liquid xenon with XeBrA: The xenon breakdown apparatus

Maintaining the electric fields necessary for the current generation of noble liquid time projection chambers (TPCs), with drift lengths exceeding 1 m, requires a large negative voltage applied to their cathode. Delivering such high voltage is associated with an elevated risk of electrostatic discharge and electroluminescence, which would be detrimental to the performance of the experiment. The Xenon Breakdown Apparatus (XeBrA) is a 5-l, high voltage test chamber built to investigate the contributing factors to electrical breakdown in noble liquids. In this work, we present the main findings after conducting scans over stressed electrode areas, surface finish, pressure, and high voltage ramp speed in the medium of liquid xenon. Area scaling and surface finish were observed to be the dominant factors affecting breakdown, whereas no significant changes were observed with varying pressure or ramp speed. A general rise in both the anode current and photon rate was observed in the last 30 s, leading up to a breakdown, with a marked increase in the last couple of seconds. In addition, the position of breakdowns was reconstructed with a system of high-speed cameras and a moderate correlation with the Fowler-Nordheim field emission model was found. Tentative evidence for bubble nucleation being the originating mechanism of breakdown in the liquid was also observed. We deem the results presented in this work to be of particular interest for the design of future, large TPCs, and practical recommendations are provided.

Results of a Search for Sub-GeV Dark Matter Using 2013 LUX Data

The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5  GeV/c^{2} using 1.4×10^{4}  kg day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.

Abstract P2-13-03: Breast cancer education, counseling, and support for Jewish women: Preliminary results of a CDC program evaluation

Background: Information and social support for women at risk for and surviving breast cancer are essential components of comprehensive clinical and public health practice in breast cancer prevention, control, and treatment. Jewish women in the US are a population of special concern due to their increased hereditary breast cancer risk for carrying BRCA1/2 gene mutations, and the dearth of culturally-relevant resources for breast cancer education and counseling. As part of a CDC initiative, Sharsheret (a non-profit breast cancer support and advocacy organization) is scaling-up its programs and services for women of all Jewish backgrounds to better meet these needs, guided by program evaluation data on client engagement practices. This abstract describes these practices and survey results.

Methods: Evaluation surveys were individually-administered via e-mail using a secure online platform. Survey invitations were sent to participants ~30 days following their utilization of Sharsheret program services. Evaluation domains included program engagement and satisfaction, health-related quality of life, and resource needs.

Results: The survey response rate was >65% (N=111), and a majority of respondents reported that they were Jewish (75%), married (76%), either or 35-45 years old (35%) or 46-64 years old (48%), and from the northeast region of the US (56%). Most respondents (88%) reported a previous breast or ovarian cancer diagnosis, and 7% indicated they carried a genetic mutation known to increase breast cancer risk. Based on the CDC's 'Health Days' measures, respondents reported a higher number unhealthy days (M=12 days per month) relative to general population averages for adult women (M=6.9 days). Respondents rated their experience with the organization highly (M=4.7 out of 5) for overall satisfaction with the quality of services utilized. There was also strong agreement among respondents (M =4.6 out of 5) about the availability and utility of patient navigation services, and the survivorship program garnered the highest level of engagement (71%) as it was utilized most often by respondents for its healthy living and nutrition resources.

Conclusion: Nonprofit organizations devoted to cancer support and advocacy fill important roles in educating and counseling women about breast cancer prevention, control, and treatment. In an era of precision medicine and discussion of population-based screening for hereditary breast cancer risk, these organizations must scale-up their information and support services. This is necessary to be available for a greater number of women, and can be expected to perform even more important and essential roles, especially for Jewish women at risk for and surviving breast cancer.

Citation Format: Fleischmann A, Silber E, Dubitsky S, Stahl S, Kravitz S, Johnson A, Murphy S, Tercyak KP. Breast cancer education, counseling, and support for Jewish women: Preliminary results of a CDC program evaluation [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-13-03.

Challenging present concepts in compression therapy: static stiffness index is not consistent and not clinically relevant

Once a circumferential force is delivered to a limb by a compression device, assuming the tension within the device remains constant, any change in the total force is dependent upon a change in circumference of the limb, with the rate of change (excluding fabric creep) being dependent on the stress strain curve of the device. This article addresses the pre-conceived and well-accepted principle that interface compression delivered by a compression device substantially increases with the position of the limb, based on the positions of sitting (non-weight bearing) to standing and/or during muscle activity (ankle dorsiflexion). Using engineering parameters and clinical measurements, the authors demonstrate that changes in interface pressure are minimal if any, and that the current concept should be modified accordingly. Declaration of interest: This study was sponsored by Carolon. L. Reid, and S. Kravitz are employees of Carolon. M. Hegarty-Craver has received monetary compensation as a researcher for Carolon.

Simulated pressure changes in multilayer, multicomponent wrap systems when transitioning from rest to standing

OBJECTIVE

The objective of this paper was to investigate the pressure applied to the lower leg by multilayer, multicomponent wrap systems, in different positions Method: The stretch profiles of five multilayer, multicomponent wrap systems were tested, three 2-layer and two 4-layer systems. These were quantified in the laboratory using a tensile testing device. The circumference of the lower leg was measured on healthy participants in three locations (ankle, B1 level, and calf) in three different postures (rest, dorsiflexion, and standing).

RESULTS

The largest changes in circumference were used to simulate the pressure changes under the multilayer, multicomponent products using Laplace's Law. While the pressure differences were large for the zinc plaster product, pressure changes ranged from 5-10mmHg for the other, more elastic products. Additionally, it was noted that the leg decreased in circumference at the B1 level and calf for the majority of participants when transitioning from sitting to standing. This decrease in size results in a decrease in bandage tension and applied pressure.

CONCLUSION

These results show that the sub-bandage pressure is not significantly affected by changes in posture when used as intended, within the therapeutic range.

DECLARATION OF INTEREST

This study was sponsored by Carolon. L. Reid, and S. Kravitz are employees of Carolon and E. Grant is a Member of the Board. M. Hegarty-Craver and C. Kwon have received monetary compensation as researchers for Carolon.

An apparatus to manipulate and identify individual Ba ions from bulk liquid Xe

We describe a system to transport and identify barium ions produced in liquid xenon, as part of R&D towards the second phase of a double beta decay experiment, nEXO. The goal is to identify the Ba ion resulting from an extremely rare nuclear decay of the isotope (136)Xe, hence providing a confirmation of the occurrence of the decay. This is achieved through Resonance Ionization Spectroscopy (RIS). In the test setup described here, Ba ions can be produced in liquid xenon or vacuum and collected on a clean substrate. This substrate is then removed to an analysis chamber under vacuum, where laser-induced thermal desorption and RIS are used with time-of-flight mass spectroscopy for positive identification of the barium decay product.

Draft genome sequence of Caminibacter mediatlanticus strain TB-2, an epsilonproteobacterium isolated from a deep-sea hydrothermal vent

Caminibacter mediatlanticus strain TB-2^T [1], is a thermophilic, anaerobic, chemolithoautotrophic bacterium, isolated from the walls of an active deep-sea hydrothermal vent chimney on the Mid-Atlantic Ridge and the type strain of the species. C. mediatlanticus is a Gram-negative member of the Epsilonproteobacteria (order Nautiliales) that grows chemolithoautotrophically with H₂ as the energy source and CO₂ as the carbon source. Nitrate or sulfur is used as the terminal electron acceptor, with resulting production of ammonium and hydrogen sulfide, respectively. In view of the widespread distribution, importance and physiological characteristics of thermophilic Epsilonproteobacteria in deep-sea geothermal environments, it is likely that these organisms provide a relevant contribution to both primary productivity and the biogeochemical cycling of carbon, nitrogen and sulfur at hydrothermal vents. Here we report the main features of the genome of C. mediatlanticus strain TB-2^T.

The JCVI standard operating procedure for annotating prokaryotic metagenomic shotgun sequencing data

The JCVI metagenomics analysis pipeline provides for the efficient and consistent annotation of shotgun metagenomics sequencing data for sampling communities of prokaryotic organisms. The process can be equally applied to individual sequence reads from traditional Sanger capillary electrophoresis sequences, newer technologies such as 454 pyrosequencing, or sequence assemblies derived from one or more of these data types. It includes the analysis of both coding and non-coding genes, whether full-length or, as is often the case for shotgun metagenomics, fragmentary. The system is designed to provide the best-supported conservative functional annotation based on a combination of trusted homology-based scientific evidence and computational assertions and an annotation value hierarchy established through extensive manual curation. The functional annotation attributes assigned by this system include gene name, gene symbol, GO terms, EC numbers, and JCVI functional role categories.

The HuRef Browser: a web resource for individual human genomics

The HuRef Genome Browser is a web application for the navigation and analysis of the previously published genome of a human individual, termed HuRef. The browser provides a comparative view between the NCBI human reference sequence and the HuRef assembly, and it enables the navigation of the HuRef genome in the context of HuRef, NCBI and Ensembl annotations. Single nucleotide polymorphisms, indels, inversions, structural and copy-number variations are shown in the context of existing functional annotations on either genome in the comparative view. Demonstrated here are some potential uses of the browser to enable a better understanding of individual human genetic variation. The browser provides full access to the underlying reads with sequence and quality information, the genome assembly and the evidence supporting the identification of DNA polymorphisms. The HuRef Browser is a unique and versatile tool for browsing genome assemblies and studying individual human sequence variation in a diploid context. The browser is available online at http://huref.jcvi.org.

Meeting report: the fourth Genomic Standards Consortium (GSC) workshop

This meeting report summarizes the proceedings of the "eGenomics: Cataloguing our Complete Genome Collection IV" workshop held June 6-8, 2007, at the National Institute for Environmental eScience (NIEeS), Cambridge, United Kingdom. This fourth workshop of the Genomic Standards Consortium (GSC) was a mix of short presentations, strategy discussions, and technical sessions. Speakers provided progress reports on the development of the "Minimum Information about a Genome Sequence" (MIGS) specification and the closely integrated "Minimum Information about a Metagenome Sequence" (MIMS) specification. The key outcome of the workshop was consensus on the next version of the MIGS/MIMS specification (v1.2). This drove further definition and restructuring of the MIGS/MIMS XML schema (syntax). With respect to semantics, a term vetting group was established to ensure that terms are properly defined and submitted to the appropriate ontology projects. Perhaps the single most important outcome of the workshop was a proposal to move beyond the concept of "minimum" to create a far richer XML schema that would define a "Genomic Contextual Data Markup Language" (GCDML) suitable for wider semantic integration across databases. GCDML will contain not only curated information (e.g., compliant with MIGS/MIMS), but also be extended to include a variety of data processing and calculations. Further information about the Genomic Standards Consortium and its range of activities can be found at http://gensc.org.

A standard MIGS/MIMS compliant XML Schema: toward the development of the Genomic Contextual Data Markup Language (GCDML)

The Genomic Contextual Data Markup Language (GCDML) is a core project of the Genomic Standards Consortium (GSC) that implements the "Minimum Information about a Genome Sequence" (MIGS) specification and its extension, the "Minimum Information about a Metagenome Sequence" (MIMS). GCDML is an XML Schema for generating MIGS/MIMS compliant reports for data entry, exchange, and storage. When mature, this sample-centric, strongly-typed schema will provide a diverse set of descriptors for describing the exact origin and processing of a biological sample, from sampling to sequencing, and subsequent analysis. Here we describe the need for such a project, outline design principles required to support the project, and make an open call for participation in defining the future content of GCDML. GCDML is freely available, and can be downloaded, along with documentation, from the GSC Web site (http://gensc.org).

The minimum information about a genome sequence (MIGS) specification

With the quantity of genomic data increasing at an exponential rate, it is imperative that these data be captured electronically, in a standard format. Standardization activities must proceed within the auspices of open-access and international working bodies. To tackle the issues surrounding the development of better descriptions of genomic investigations, we have formed the Genomic Standards Consortium (GSC). Here, we introduce the minimum information about a genome sequence (MIGS) specification with the intent of promoting participation in its development and discussing the resources that will be required to develop improved mechanisms of metadata capture and exchange. As part of its wider goals, the GSC also supports improving the 'transparency' of the information contained in existing genomic databases.

The Sorcerer II Global Ocean Sampling expedition: northwest Atlantic through eastern tropical Pacific

The world's oceans contain a complex mixture of micro-organisms that are for the most part, uncharacterized both genetically and biochemically. We report here a metagenomic study of the marine planktonic microbiota in which surface (mostly marine) water samples were analyzed as part of the Sorcerer II Global Ocean Sampling expedition. These samples, collected across a several-thousand km transect from the North Atlantic through the Panama Canal and ending in the South Pacific yielded an extensive dataset consisting of 7.7 million sequencing reads (6.3 billion bp). Though a few major microbial clades dominate the planktonic marine niche, the dataset contains great diversity with 85% of the assembled sequence and 57% of the unassembled data being unique at a 98% sequence identity cutoff. Using the metadata associated with each sample and sequencing library, we developed new comparative genomic and assembly methods. One comparative genomic method, termed “fragment recruitment,” addressed questions of genome structure, evolution, and taxonomic or phylogenetic diversity, as well as the biochemical diversity of genes and gene families. A second method, termed “extreme assembly,” made possible the assembly and reconstruction of large segments of abundant but clearly nonclonal organisms. Within all abundant populations analyzed, we found extensive intra-ribotype diversity in several forms: (1) extensive sequence variation within orthologous regions throughout a given genome; despite coverage of individual ribotypes approaching 500-fold, most individual sequencing reads are unique; (2) numerous changes in gene content some with direct adaptive implications; and (3) hypervariable genomic islands that are too variable to assemble. The intra-ribotype diversity is organized into genetically isolated populations that have overlapping but independent distributions, implying distinct environmental preference. We present novel methods for measuring the genomic similarity between metagenomic samples and show how they may be grouped into several community types. Specific functional adaptations can be identified both within individual ribotypes and across the entire community, including proteorhodopsin spectral tuning and the presence or absence of the phosphate-binding gene PstS.

Marine microbes remain elusive and mysterious, even though they are the most abundant life form in the ocean, form the base of the marine food web, and drive energy and nutrient cycling. We know so little about the vast majority of microbes because only a small percentage can be cultivated and studied in the lab. Here we report on the Global Ocean Sampling expedition, an environmental metagenomics project that aims to shed light on the role of marine microbes by sequencing their DNA without first needing to isolate individual organisms. A total of 41 different samples were taken from a wide variety of aquatic habitats collected over 8,000 km. The resulting 7.7 million sequencing reads provide an unprecedented look at the incredible diversity and heterogeneity in naturally occurring microbial populations. We have developed new bioinformatic methods to reconstitute large portions of both cultured and uncultured microbial genomes. Organism diversity is analyzed in relation to sampling locations and environmental pressures. Taken together, these data and analyses serve as a foundation for greatly expanding our understanding of individual microbial lineages and their evolution, the nature of marine microbial communities, and how they are impacted by and impact our world.

TheSorcerer II GOS expedition, data sampling, and analysis is described. The immense diversity in the sequence data required novel comparative genomic assembly methods, which uncovered genomic differences that marker-based methods could not.

Genome sequence of Aedes aegypti, a major arbovirus vector

We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species.

Diabetic foot disorders: a clinical practice guideline. American College of Foot and Ankle Surgeons

Foot ulcerations, infections, and Charcot neuropathic osteoarthropathy are three serious foot complications of diabetes mellitus that can too frequently lead to gangrene and lower limb amputation. Consequently, foot disorders are one of the leading causes of hospitalization for persons with diabetes and can account for expenditures in the billions of dollars annually in the U.S. alone. Although not all foot complications can be prevented, dramatic reductions in their frequency have been obtained through the implementation of a multidisciplinary team approach to patient management. Using this concept, the authors present a Clinical Practice Guideline for diabetic foot disorders based on currently available evidence. The underlying pathophysiology and treatment of diabetic foot ulcers, infections, and the diabetic Charcot foot are thoroughly reviewed. Although these guidelines cannot and should not dictate the standard of care for all affected patients, they are intended to provide evidence-based guidance for general patterns of practice. The goal of a major reduction in diabetic limb amputations is certainly possible if these concepts are embraced and incorporated into patient management protocols.

Diabetic foot disorders. A clinical practice guideline. For the American College of Foot and Ankle Surgeons and the American College of Foot and Ankle Orthopedics and Medicine

Foot ulcerations, infections, and Charcot neuropathic osteoarthropathy are three serious foot complications of diabetes mellitus that can too frequently lead to gangrene and lower limb amputation. Consequently, foot disorders are one of the leading causes of hospitalization for persons with diabetes and can account for expenditures in the billions of dollars annually in the U.S. alone. Although not all foot complications can be prevented, dramatic reductions in their frequency have been obtained through the implementation of a multidisciplinary team approach to patient management. Using this concept, the authors present a Clinical Practice Guideline for diabetic foot disorders based on currently available evidence. The underlying pathophysiology and treatment of diabetic foot ulcers, infections, and the diabetic Charcot foot are thoroughly reviewed. Although these guidelines cannot and should not dictate the standard of care for all affected patients, they are intended to provide evidence-based guidance for general patterns of practice. The goal of a major reduction in diabetic limb amputations is certainly possible if these concepts are embraced and incorporated into patient management protocols.

The sequence of the human genome

A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies-a whole-genome assembly and a regional chromosome assembly-were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional approximately 12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.

The genome sequence of Drosophila melanogaster

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

Learned helplessness and the self-control model of depression

Self-reinforcement, one element of the self-control model of depression proposed by Rehm, was evaluated as to its relationship with Seligman's learned helplessness phenomenon. Within a nonclinical population, subjects were divided by their Beck Depression Inventory scores into a Non-depressed group and a Very Mildly Depressed group. Subjects in each group were exposed to one of three treatments, Learned Helplessness, Nonlearned Helplessness, and Control conditions based upon the Levine multidimensional discrimination task. Depressed subjects gave significantly more self-punishment and less self-reward than nondepressed subjects after exposure to the experimental conditions. A significant interaction of depressed X treatment condition and post hoc analyses suggest an explanation for the previously noted facilitation effects of learned helplessness and suggest a self-control inoculation against increased depression when normals are exposed to conditions of learned helplessness. Effects of the learned-helplessness experience are related to the self-control model of depression.