On some new approaches to practical Slepian-Wolf compression inspired by channel coding

This paper considers the problem, first introduced by Ahlswede and Körner in 1975, of lossless source coding with coded side information. Specifically, let X and Y be two random variables such that X is desired losslessly at the decoder while Y serves as side information. The random variables are encoded independently, and both descriptions are used by the decoder to reconstruct X. Ahlswede and Körner describe the achievable rate region in terms of an auxiliary random variable. This paper gives a partial solution for the optimal auxiliary random variable, thereby describing part of the rate region explicitly in terms of the distribution of X and Y

The SOX11 transcription factor is a critical regulator of basal-like breast cancer growth, invasion, and basal-like gene expression.

Basal-like breast cancers (BLBCs) are aggressive breast cancers associated with poor survival. Defining the key drivers of BLBC growth will allow identification of molecules for targeted therapy. In this study, we performed a primary screen integrating multiple assays that compare transcription factor expression and activity in BLBC and non-BLBC at the RNA, DNA, and protein levels. This integrated screen identified 33 transcription factors that were elevated in BLBC in multiple assays comparing mRNA expression, DNA cis-element sequences, or protein DNA-binding activity. In a secondary screen to identify transcription factors critical for BLBC cell growth, 8 of the 33 candidate transcription factors (TFs) were found to be necessary for growth in at least two of three BLBC cell lines. Of these 8 transcription factors, SOX11 was the only transcription factor required for BLBC growth, but not for growth of non-BLBC cells. Our studies demonstrate that SOX11 is a critical regulator of multiple BLBC phenotypes, including growth, migration, invasion, and expression of signature BLBC genes. High SOX11 expression was also found to be an independent prognostic indicator of poor survival in women with breast cancer. These results identify SOX11 as a potential target for the treatment of BLBC, the most aggressive form of breast cancer

Stigma resistance at the personal, peer, and public levels: A new conceptual model.

Stigma resistance is consistently linked with key recovery outcomes, yet theoretical work is limited. This study explored stigma resistance from the perspective of individuals with serious mental illness (SMI). Twenty-four individuals with SMI who were either peer-service providers (those with lived experience providing services; N = 14) or consumers of mental health services (N = 10) engaged in semistructured interviews regarding experiences with stigma, self-stigma, and stigma resistance, including key elements of this process and examples of situations in which they resisted stigma. Stigma resistance is an ongoing, active process that involves using one’s experiences, knowledge, and sets of skills at the (1) personal, (2) peer, and (3) public levels. Stigma resistance at the personal level involves (a) not believing stigma or catching and challenging stigmatizing thoughts, (b) empowering oneself by learning about mental health and recovery, (c) maintaining one’s recovery and proving stigma wrong, and (d) developing a meaningful identity apart from mental illness. Stigma resistance at the peer level involves using one’s experiences to help others fight stigma and at the public level, resistance involved (a) education, (b) challenging stigma, (c) disclosing one’s lived experience, and (d) advocacy work. Findings present a more nuanced conceptualization of resisting stigma, grounded in the experiences of people with SMI. Stigma resistance is an ongoing, active process of using one’s experiences, skills, and knowledge to develop a positive identity. Interventions should consider focusing on personal stigma resistance early on and increasing the incorporation of peers into services

Low-Complexity Approaches to Slepian–Wolf Near-Lossless Distributed Data Compression

This paper discusses the Slepian–Wolf problem of distributed near-lossless compression of correlated sources. We introduce practical new tools for communicating at all rates in the achievable region. The technique employs a simple “source-splitting” strategy that does not require common sources of randomness at the encoders and decoders. This approach allows for pipelined encoding and decoding so that the system operates with the complexity of a single user encoder and decoder. Moreover, when this splitting approach is used in conjunction with iterative decoding methods, it produces a significant simplification of the decoding process. We demonstrate this approach for synthetically generated data. Finally, we consider the Slepian–Wolf problem when linear codes are used as syndrome-formers and consider a linear programming relaxation to maximum-likelihood (ML) sequence decoding. We note that the fractional vertices of the relaxed polytope compete with the optimal solution in a manner analogous to that observed when the “min-sum” iterative decoding algorithm is applied. This relaxation exhibits the ML-certificate property: if an integral solution is found, it is the ML solution. For symmetric binary joint distributions, we show that selecting easily constructable “expander”-style low-density parity check codes (LDPCs) as syndrome-formers admits a positive error exponent and therefore provably good performance

Effective mass theory of monolayer \delta-doping in the high-density limit

Monolayer \delta-doped structures in silicon have attracted renewed interest with their recent incorporation into atomic-scale device fabrication strategies as source and drain electrodes and in-plane gates. Modeling the physics of \delta-doping at this scale proves challenging, however, due to the large computational overhead associated with ab initio and atomistic methods. Here, we develop an analytical theory based on an effective mass approximation. We specifically consider the Si:P materials system, and the limit of high donor density, which has been the subject of recent experiments. In this case, metallic behavior including screening tends to smooth out the local disorder potential associated with random dopant placement. While smooth potentials may be difficult to incorporate into microscopic, single-electron analyses, the problem is easily treated in the effective mass theory by means of a jellium approximation for the ionic charge. We then go beyond the analytic model, incorporating exchange and correlation effects within a simple numerical model. We argue that such an approach is appropriate for describing realistic, high-density, highly disordered devices, providing results comparable to density functional theory, but with greater intuitive appeal, and lower computational effort. We investigate valley coupling in these structures, finding that valley splitting in the low-lying \Gamma band grows much more quickly than the \Gamma-\Delta band splitting at high densities. We also find that many-body exchange and correlation corrections affect the valley splitting more strongly than they affect the band splitting

Parental Co‐Construction of 5‐ to 13‐Year‐Olds\u27 Global Self‐Esteem Through Reminiscing About Past Events

The current study explored parental processes associated with children\u27s global self‐esteem development. Eighty 5‐ to 13‐year‐olds and one of their parents provided qualitative and quantitative data through questionnaires, open‐ended questions, and a laboratory‐based reminiscing task. Parents who included more explanations of emotions when writing about the lowest points in their lives were more likely to discuss explanations of emotions experienced in negative past events with their child, which was associated with child attachment security. Attachment was associated with concurrent self‐esteem, which predicted relative increases in self‐esteem 16 months later, on average. Finally, parent support also predicted residual increases in self‐esteem. Findings extend prior research by including younger ages and uncovering a process by which two theoretically relevant parenting behaviors impact self‐esteem development

Parents Served by Assertive Community Treatment: A Needs Based Assessment

poster abstractAssertive Community Treatment (ACT) represents an effective treatment for individuals with severe mental illness. Though studies estimate roughly half of all people with severe mental illness are parents, little is known about consumers receiving ACT services who are parents. Thus, the purpose of the present study was to 1) estimate the prevalence of parent ACT consumers, 2) identify current ACT team policies and services for parent consumers, and 3) examine the perspective of parent consumers served by ACT teams. Quantitative and qualitative data were collected and analyzed via two studies. In study 1, 82 ACT providers from 76 teams in the US and Canada were surveyed. Providers estimated roughly 21.6% of ACT consumers were parents. Only 46.3% of providers reported formally asking consumers about parental status and 20.7% of providers belonged to ACT teams that offer services designed for parent consumers. The majority of providers (75.6%) reported negative or mixed attitudes about parents with severe mental illness. In study 2, seventeen parents receiving ACT services were interviewed. All parents endorsed positive attitudes about parenting, though most (76.5%) also identified negative aspects of parenting. Almost all parents (88.2%) reported loss of custody at least once. Parents expressed interest in parent-focused treatment services like family therapy, parenting skills, communication skills training, and peer support groups. Regarding satisfaction with ACT services, most parents with adult children (87.5%) reported no unmet parent-related needs and high satisfaction (4.63 of 5) with ACT services, whereas parents with young children (77.8%) reported unmet parenting needs and low satisfaction (3.78 of 5) with ACT services. Thus, results indicate the ACT treatment model may not be adequately serving parents with young, dependent children. Overall, findings suggest the need for more focus on parents with severe mental illness, including formal identification of parental status and parent-related treatment services and support

Sarcospan Regulates Cardiac Isoproterenol Response and Prevents Duchenne Muscular Dystrophy-Associated Cardiomyopathy.

BackgroundDuchenne muscular dystrophy is a fatal cardiac and skeletal muscle disease resulting from mutations in the dystrophin gene. We have previously demonstrated that a dystrophin-associated protein, sarcospan (SSPN), ameliorated Duchenne muscular dystrophy skeletal muscle degeneration by activating compensatory pathways that regulate muscle cell adhesion (laminin-binding) to the extracellular matrix. Conversely, loss of SSPN destabilized skeletal muscle adhesion, hampered muscle regeneration, and reduced force properties. Given the importance of SSPN to skeletal muscle, we investigated the consequences of SSPN ablation in cardiac muscle and determined whether overexpression of SSPN into mdx mice ameliorates cardiac disease symptoms associated with Duchenne muscular dystrophy cardiomyopathy.Methods and resultsSSPN-null mice exhibited cardiac enlargement, exacerbated cardiomyocyte hypertrophy, and increased fibrosis in response to β-adrenergic challenge (isoproterenol; 0.8 mg/day per 2 weeks). Biochemical analysis of SSPN-null cardiac muscle revealed reduced sarcolemma localization of many proteins with a known role in cardiomyopathy pathogenesis: dystrophin, the sarcoglycans (α-, δ-, and γ-subunits), and β1D integrin. Transgenic overexpression of SSPN in Duchenne muscular dystrophy mice (mdx(TG)) improved cardiomyofiber cell adhesion, sarcolemma integrity, cardiac functional parameters, as well as increased expression of compensatory transmembrane proteins that mediate attachment to the extracellular matrix.ConclusionsSSPN regulates sarcolemmal expression of laminin-binding complexes that are critical to cardiac muscle function and protects against transient and chronic injury, including inherited cardiomyopathy

A Simple Model of Epidemics with Pathogen Mutation

We study how the interplay between the memory immune response and pathogen mutation affects epidemic dynamics in two related models. The first explicitly models pathogen mutation and individual memory immune responses, with contacted individuals becoming infected only if they are exposed to strains that are significantly different from other strains in their memory repertoire. The second model is a reduction of the first to a system of difference equations. In this case, individuals spend a fixed amount of time in a generalized immune class. In both models, we observe four fundamentally different types of behavior, depending on parameters: (1) pathogen extinction due to lack of contact between individuals, (2) endemic infection (3) periodic epidemic outbreaks, and (4) one or more outbreaks followed by extinction of the epidemic due to extremely low minima in the oscillations. We analyze both models to determine the location of each transition. Our main result is that pathogens in highly connected populations must mutate rapidly in order to remain viable.Comment: 9 pages, 11 figure