Quantum criticality out of equilibrium in the pseudogap Kondo model

We theoretically investigate the non-equilibrium quantum phase transition in a generic setup: the pseudogap Kondo model where a quantum dot couples to two-left (L) and right (R)-voltage-biased fermionic leads with power-law density of states (DOS) with respect to their Fermi levels {\mu}_L/R, {\rho}_c,L(R) ({\omega}) \propto |{\omega} - {\mu}_L(R) |r, and 0 < r < 1. In equilibrium (zero bias voltage) and for 0 < r < 1/2, with increasing Kondo correlations, in the presence of particle-hole symmetry this model exhibits a quantum phase transition from a unscreened local moment (LM) phase to the Kondo phase. Via a controlled frequency-dependent renormalization group (RG) approach, we compute analytically and numerically the non-equilibrium conductance, conduction electron T-matrix and local spin susceptibility at finite bias voltages near criticality. The current-induced decoherence shows distinct nonequilibrium scaling, leading to new universal non-equilibrium quantum critical behaviors in the above observables. Relevance of our results for the experiments is discussed.Comment: 4.1 pages, 2 figure

Improving the Usability of Organizational Data Systems

For research data repositories, web interfaces are usually the primary, if not the only, method that data users have to interact with repository systems. Data users often search, discover, understand, access, and sometimes use data directly through repository web interfaces. Given that sub-par user interfaces can reduce the ability of users to locate, obtain, and use data, it is important to consider how repositories’ web interfaces can be evaluated and improved in order to ensure useful and successful user interactions. This paper discusses how usability assessment techniques are being applied to improve the functioning of data repository interfaces at the National Center for Atmospheric Research (NCAR). At NCAR, a new suite of data system tools is being developed and collectively called the NCAR Digital Asset Services Hub (DASH). Usability evaluation techniques have been used throughout the NCAR DASH design and implementation cycles in order to ensure that the systems work well together for the intended user base. By applying user study, paper prototype, competitive analysis, journey mapping, and heuristic evaluation, the NCAR DASH Search and Repository experiences provide examples for how data systems can benefit from usability principles and techniques. Integrating usability principles and techniques into repository system design and implementation workflows helps to optimize the systems’ overall user experience

Recognizing the Diversity of Contributions: A Case Study for Framing Attribution and Acknowledgement for Scientific Data

As scientific data volumes, format types, and sources increase rapidly with the invention and improvement of scientific capabilities, the resulting datasets are becoming more complex to manage as well. One of the significant management challenges is pulling apart the individual contributions of specific people and organizations within large, complex projects. This is important for two aspects: 1) assigning responsibility and accountability for scientific work, and 2) giving professional credit to individuals (e.g. hiring, promotion, and tenure) who work within such large projects. This paper aims to review the extant practice of data attribution and how it may be improved. Through a case study of creating a detailed attribution record for a climate model dataset, the paper evaluates the strengths and weaknesses of the current data attribution method and proposes an alternative attribution framework accordingly. The paper concludes by demonstrating that, analogous to acknowledging the different roles and responsibilities shown in movie credits, the methodology developed in the study could be used in general to identify and map out the relationships among the organizations and individuals who had contributed to a dataset.  As a result, the framework could be applied to create data attribution for other dataset types beyond climate model datasets. 

Formalizing an Attribution Framework for Scientific Data/Software Products and Collections

As scientific research and development become more collaborative, the diversity of skills and expertise involved in producing scientific data are expanding as well. Since recognition of contribution has significant academic and professional impact for participants in scientific projects, it is important to integrate attribution and acknowledgement of scientific contributions into the research and data lifecycle. However, defining and clarifying contributions and the relationship of specific individuals and organizations can be challenging, especially when balancing the needs and interests of diverse partners. Designing an implementation method for attributing scientific contributions within complex projects that can allow ease of use and integration with existing documentation formats is another crucial consideration. To provide a versatile mechanism for organizing, documenting, and storing contributions to different types of scientific projects and their related products, an attribution and acknowledgement matrix and XML schema have been created as part of the Attribution and Acknowledgement Content Framework (AACF). Leveraging the taxonomies of contribution roles and types that have been developed and published previously, the authors consolidated 16 contribution types that could be considered and used when accrediting team member’s contributions. Using these contribution types, specific information regarding the contributing organizations and individuals can be documented using the AACF. This paper provides the background and motivations for creating the current version of the AACF Matrix and Schema, followed by demonstrations of the process and the results of using the Matrix and the Schema to record the contribution information of different sample datasets. The paper concludes by highlighting the key feedback and features to be examined in order to improve the next revisions of the Matrix and the Schema.

Video-thoracoscopic enucleation of esophageal leiomyoma

<p>Abstract</p> <p>Background</p> <p>Leiomyoma is the most common benign tumor of the esophagus. Surgical enucleation is indicated in case of symptoms or an unclear diagnosis, and open thoracotomy has long been the standard approach for this procedure. However, enucleation through video assisted thoracoscopic surgery (VATS) has been developed as a preferred approach for most lesions in recent years.</p> <p>Method</p> <p>Herein we report our twelve patients (seven men and five women, with median age of 42 years) from 2001 to 2009, who underwent enucleation through VATS for esophageal leiomyomas, with a size from 1 to 8 cm in diameter (median: 5), and at different locations, from the thoracic outlet to near the diaphragmatic level of the thoracic esophagus. Intraoperative fiberoptic esophagoscopy was performed in two patients for localization by illumination. A right-sided approach was performed in eight cases (upper two thirds of esophagus) and the left-sided in another four cases (lower third of esophagus).</p> <p>Result</p> <p>The median operative time was 95 minutes (70 to 230 minutes). Four of them required small utility incisions (4-6 cm) for better exploration and manipulation. There were no major complications, such as death or empyema due to leaks from mucosal tears, and the presenting symptoms were improved during the follow-up period, from 12 to 98 months.</p> <p>Conclusion</p> <p>VATS can be considered as an initial approach for most patients with esophageal leiomyomas, even large in size, irregular in shape, or at unfavorable location. It is a safe, minimally invasive, and effective treatment. However, conversion to open thoracotomy should be required for the sake of clinical or technical concern.</p

THE EFFECT OF INSULIN AND CARBOHYDRATE SUPPLEMENTATION ON GLYCOGEN REPLENISHMENT AMONG DIFFERENT HINDLIMB MUSCLES IN RATS FOLLOWING PROLONGED SWIMMING

In the present study we investigated the interactive effects of insulin and carbohydrate on glycogen replenishment in different rat hindlimb muscles. Forty male Sprague Dawley rats were assigned to 5 groups, including 1) sedentary control with carbohydrate supplement (2 g glucose · kg body wt-1), 2) sedentary rats with 16 hours recovery, carbohydrate and insulin (0.5 U · kg body wt-1), 3) swimming without recovery, 4) swimming with 16 hours recovery and carbohydrate supplement, and 5) swimming with 16 hours recovery, carbohydrate and insulin. The swimming protocol consisted of two 3 h swimming sections, which were separated by a 45 min rest. The insulin and carbohydrate were administered to the rats immediately after exercise. At the end of the experiment, the soleus (S), plantaris (P), quadriceps (Q) and gastrocnemius (G) were surgically excised to evaluate glycogen utilization and replenishment. We observed that glycogen utilization was significantly lower in G and Q than S and P during swimming (p <0.05), and S showed the greatest capacity of glycogen resynthesis after post-exercise recovery (p <0.05). In the sedentary state, the glycogen synthesis did not differ among hindlimb muscles during insulin and carbohydrate treatments. Interestingly, with insulin and carbohydrate, the glycogen resynthesis in S and P were significantly greater than in Q and G following post-exercise recovery (p <0.05). We therefore concluded that the soleus and plantaris are the primary working muscles during swimming, and the greatest glycogen replenishment capacity of the soleus during post-exercise recovery is likely due to its highest insulin sensitivity

Elevated Krüppel-like factor 4 transcription factor in canine mammary carcinoma

<p>Abstract</p> <p>Background</p> <p>Krüppel-like factors (KLFs) are critical regulators of biological and physiological systems and have been extensively studied for their roles in cell proliferation, differentiation and survival in the context of cancer. Among the KLFs, KLF4 is highly expressed in human breast cancers and plays an oncogenic role. The present study examined the expression of KLF4 and assessed its significance in canine mammary carcinoma.</p> <p>Results</p> <p>Immunohistochemistry was employed to investigate the expression of KLF4 in 142 cases of canine mammary tumor. 75 of the 142 (52.8%) cases were histologically confirmed as mammary carcinoma. Quantification of immunohistochemistry was carried out using Quick score which multiply the staining intensity by the percentage of positive cells. High KLF4 expression was identified in 44 of the 75 (59%) dogs with mammary carcinoma and none in the benign cases. High KLF4 expression occurred only in the tumor cells and not the adjacent normal cells in mammary carcinoma (P < 0.001). Moreover, the high expression level of KLF4 expression was statistically associated with poor grade, late stage, histological subtypes of simple and complex carcinoma, and shorter 24-month survival. The Kaplan-Meier survival analysis also indicated that dogs with high nuclear KLF4 expression had a significantly shorter survival than those with low/moderate KLF4 expression (P = 0.011).</p> <p>Conclusions</p> <p>KLF4 is highly and frequently expressed in canine mammary carcinoma and correlates with a more aggressive phenotype.</p

Overexpression of hTERT increases stem-like properties and decreases spontaneous differentiation in human mesenchymal stem cell lines

To overcome loss of stem-like properties and spontaneous differentiation those hinder the expansion and application of human mesenchymal stem cells (hMSCs), we have clonally isolated permanent and stable human MSC lines by ectopic overexpression of primary cell cultures of hMSCs with HPV 16 E6E7 and human telomerase reverse transcriptase (hTERT) genes. These cells were found to have a differentiation potential far beyond the ordinary hMSCs. They expressed trophoectoderm and germline specific markers upon differentiation with BMP4 and retinoic acid, respectively. Furthermore, they displayed higher osteogenic and neural differentiation efficiency than primary hMSCs or hMSCs expressed HPV16 E6E7 alone with a decrease in methylation level as proven by a global CpG island methylation profile analysis. Notably, the demethylated CpG islands were highly associated with development and differentiation associated genes. Principal component analysis further pointed out the expression profile of the cells converged toward embryonic stem cells. These data demonstrate these cells not only are a useful tool for the studies of cell differentiation both for the mesenchymal and neurogenic lineages, but also provide a valuable source of cells for cell therapy studies in animal models of skeletal and neurological disorders