46 research outputs found

    Energy landscapes, ideal glasses, and their equation of state

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    Using the inherent structure formalism originally proposed by Stillinger and Weber [Phys. Rev. A 25, 978 (1982)], we generalize the thermodynamics of an energy landscape that has an ideal glass transition and derive the consequences for its equation of state. In doing so, we identify a separation of configurational and vibrational contributions to the pressure that corresponds with simulation studies performed in the inherent structure formalism. We develop an elementary model of landscapes appropriate to simple liquids which is based on the scaling properties of the soft-sphere potential complemented with a mean-field attraction. The resulting equation of state provides an accurate representation of simulation data for the Lennard-Jones fluid, suggesting the usefulness of a landscape-based formulation of supercooled liquid thermodynamics. Finally, we consider the implications of both the general theory and the model with respect to the so-called Sastry density and the ideal glass transition. Our analysis shows that a quantitative connection can be made between properties of the landscape and a simulation-determined Sastry density, and it emphasizes the distinction between an ideal glass transition and a Kauzmann equal-entropy condition.Comment: 11 pages, 3 figure

    Peer Connect for African American breast cancer survivors and caregivers: a train-the-trainer approach for peer support

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    Racial disparities in breast cancer survivorship are a major concern nationally. How survivors cope with cancer and re-frame their lives is a critical part of survivorship. Community-academic research partnerships may facilitate access to much-needed psychosocial support for African American survivors and caregivers in rural areas, but drivers of successful intervention implementation are not well understood. The purpose of this study was to describe the training and evaluation of Community Coaches and Guides (i.e., peer supporters) using the Peer Connect program for African American breast cancer survivors and caregivers. Community engagement strategies were used to implement the training component of Peer Connect, an evidence-based program grounded in the Diffusion of Innovation Theory utilizing motivational interviewing techniques (MI) and a "train-the-trainer" model. Quantitative and qualitative methods examined implementation outcomes of feasibility, MI fidelity, and acceptability-precursor outcomes that must be achieved before examining intervention impact vis-à-vis changes in support care. Training was feasible to implement and replicable by the trained Community Coaches. Beyond feasibility and replicability, success was modest regarding MI fidelity. Benefits (e.g., serving as role models and having safe sources of support) and lessons learned (e.g., need for additional quality control) were identified as both facilitators and barriers to implementation and as factors that could impact the effectiveness of community-engaged programs to improve survivorship outcomes. Peer Connect, like other programs that employ community-engagement strategies, holds promise to meet the psychosocial support needs of diverse rural cancer survivor populations

    Implementing a One-on-One Peer Support Program for Cancer Survivors Using a Motivational Interviewing Approach: Results and Lessons Learned

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    Peer Connect matches cancer survivors and caregivers (guides) with those currently experiencing cancer-related issues seeking support (partners). Motivational interviewing (MI)-based communication skills are taught to provide patient-centered support. There is little guidance about MI-based applications with cancer survivors who may have multiple coping needs. This paper addresses the results and lessons learned from implementing Peer Connect. Thirteen cancer survivors and two caregivers received a 2-dayMI, DVD-based training along with six supplemental sessions. Nineteen partners were matched with guides and received telephone support. Evaluation included guide skill assessment (Motivational Interviewing Treatment Integrity Code) and 6-month follow-up surveys with guides and partners. Guides demonstrated MI proficiency and perceived their training as effective. Guides provided on average of five calls to each partner. Conversation topics included cancer fears, family support needs, coping and care issues, and cancer-related decisions. Partners reported that guides provided a listening ear, were supportive, and nonjudgmental. Limited time availability of some guides was a challenge. MI can provide support for cancer survivors and caregivers without specific behavioral concerns (e.g., weight and smoking). An MI support model was both feasible and effective and can provide additional support outside of the medical system

    Cancer Screening Patterns by Weight Group and Gender for Urban African American Church Members

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    Obese white women have lower rates of cancer screening compared to non-obese women. This study will determine if a relationship exists between weight and adherence to cancer screening guidelines among African Americans

    The Gestational Diabetes Management System (GooDMomS): development, feasibility and lessons learned from a patient-informed, web-based pregnancy and postpartum lifestyle intervention

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    Abstract Background Gestational diabetes mellitus (GDM) contributes to the epidemic of diabetes and obesity in mothers and their offspring. The primary objective of this pilot study was to: 1) refine the GDM Management System (GooDMomS), a web-based pregnancy and postpartum behavioral intervention and 2) assess the feasibility of the intervention. Methods In phase 1, ten semi-structured interviews were conducted with women experiencing current or recent GDM mellitus GDM to garner pilot data on the web based intervention interface, content, and to solicit recommendations from women about refinements to enhance the GooDMomS intervention site. Interviews were audiotaped, transcribed and independently reviewed to identify major themes with Atlas.ti v7.0. In phase 2, a single-arm feasibility study was conducted and 23 participants were enrolled in the GooDMomS program. Participants received web lessons, self-tracking of weight and glucose, automated feedback and access to a message board for peer support. The primary outcome was feasibility, including recruitment and retention and acceptability. Secondary outcomes included the proportion of women whose gestational weight gain (GWG) was within the Institute of Medicine (IOM) guidelines and who were able to return to their pre-pregnancy weight after delivery. Results Comments from semi-structured interviews focused on: 1) usability of the on-line self-monitoring diary and tracking system, 2) access to a safe, reliable social network for peer support and 3) ability of prenatal clinicians to access the on-line diary for clinical management. Overall, 21 (91 %) completed the pregnancy phase. 15/21 (71 %) of participants were within the Institute of Medicine (IOM) guidelines for GWG. Sixteen (70 %) completed the postpartum phase. 7/16 (43 %) and 9/16 (56 %) of participants returned to their pre-pregnancy weight at 6 and 30 weeks postpartum, respectively. Conclusions This study documents the feasibility of the GooDMomS program. The results can have implications for web technology in perinatal care and inform the current care paradigm for women with GDM. Findings are supportive of further research with recruitment of a larger sample of participants and comparison of the outcomes with the intervention and standard care. Trial registration The study was registered at ClinicalTrials.gov on May 15, 2012 under protocol no. NCT01600534

    Promoting Fruit and Vegetable Consumption Among Members of Black Churches, Michigan and North Carolina, 2008–2010

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    IntroductionEvidence-based health promotion programs that are disseminated in community settings can improve population health. However, little is known about how effective such programs are when they are implemented in communities. We examined community implementation of an evidence-based program, Body and Soul, to promote consumption of fruits and vegetables.MethodsWe randomly assigned 19 churches to 1 of 2 arms, a colon cancer screening intervention or Body and Soul. We conducted our study from 2008 through 2010. We used the RE-AIM (reach, effectiveness, adoption, implementation, and maintenance) framework to evaluate the program and collected data via participant surveys, on-site observations, and interviews with church coordinators and pastors.ResultsMembers of 8 churches in Michigan and North Carolina participated in the Body and Soul program. Mean fruit and vegetable consumption increased from baseline (3.9 servings/d) to follow-up (+0.35, P = .04). The program reached 41.4% of the eligible congregation. Six of the 8 churches partially or fully completed at least 3 of the 4 program components. Six churches expressed intention to maintain the program. Church coordinators reported limited time and help to plan and implement activities, competing church events, and lack of motivation among congregation members as barriers to implementation.ConclusionsThe RE-AIM framework provided an effective approach to evaluating the dissemination of an evidence-based program to promote health. Stronger emphasis should be placed on providing technical assistance as a way to improve other community-based translational efforts

    Distinct Binding and Immunogenic Properties of the Gonococcal Homologue of Meningococcal Factor H Binding Protein

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    Neisseria meningitidis is a leading cause of sepsis and meningitis. The bacterium recruits factor H (fH), a negative regulator of the complement system, to its surface via fH binding protein (fHbp), providing a mechanism to avoid complement-mediated killing. fHbp is an important antigen that elicits protective immunity against the meningococcus and has been divided into three different variant groups, V1, V2 and V3, or families A and B. However, immunisation with fHbp V1 does not result in cross-protection against V2 and V3 and vice versa. Furthermore, high affinity binding of fH could impair immune responses against fHbp. Here, we investigate a homologue of fHbp in Neisseria gonorrhoeae, designated as Gonococcal homologue of fHbp (Ghfp) which we show is a promising vaccine candidate for N. meningitidis. We demonstrate that Gfhp is not expressed on the surface of the gonococcus and, despite its high level of identity with fHbp, does not bind fH. Substitution of only two amino acids in Ghfp is sufficient to confer fH binding, while the corresponding residues in V3 fHbp are essential for high affinity fH binding. Furthermore, immune responses against Ghfp recognise V1, V2 and V3 fHbps expressed by a range of clinical isolates, and have serum bactericidal activity against N. meningitidis expressing fHbps from all variant groups

    Deciphering the stem cell machinery as a basis for understanding the molecular mechanism underlying reprogramming

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    Stem cells provide fascinating prospects for biomedical applications by combining the ability to renew themselves and to differentiate into specialized cell types. Since the first isolation of embryonic stem (ES) cells about 30 years ago, there has been a series of groundbreaking discoveries that have the potential to revolutionize modern life science. For a long time, embryos or germ cell-derived cells were thought to be the only source of pluripotency—a dogma that has been challenged during the last decade. Several findings revealed that cell differentiation from (stem) cells to mature cells is not in fact an irreversible process. The molecular mechanism underlying cellular reprogramming is poorly understood thus far. Identifying how pluripotency maintenance takes place in ES cells can help us to understand how pluripotency induction is regulated. Here, we review recent advances in the field of stem cell regulation focusing on key transcription factors and their functional interplay with non-coding RNAs

    Molecular marks for epigenetic identification of developmental and cancer stem cells

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    Epigenetic regulations of genes by reversible methylation of DNA (at the carbon-5 of cytosine) and numerous reversible modifications of histones play important roles in normal physiology and development, and epigenetic deregulations are associated with developmental disorders and various disease states, including cancer. Stem cells have the capacity to self-renew indefinitely. Similar to stem cells, some malignant cells have the capacity to divide indefinitely and are referred to as cancer stem cells. In recent times, direct correlation between epigenetic modifications and reprogramming of stem cell and cancer stem cell is emerging. Major discoveries were made with investigations on reprogramming gene products, also known as master regulators of totipotency and inducer of pluoripotency, namely, OCT4, NANOG, cMYC, SOX2, Klf4, and LIN28. The challenge to induce pluripotency is the insertion of four reprogramming genes (Oct4, Sox2, Klf4, and c-Myc) into the genome. There are always risks of silencing of these genes by epigenetic modifications in the host cells, particularly, when introduced through retroviral techniques. In this contribution, we will discuss some of the major discoveries on epigenetic modifications within the chromatin of various genes associated with cancer progression and cancer stem cells in comparison to normal development of stem cell. These modifications may be considered as molecular signatures for predicting disorders of development and for identifying disease states
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