A Nonlinear Delay Model for Metabolic Oscillations in Yeast Cells.

We introduce two time-delay models of metabolic oscillations in yeast cells. Our model tests a hypothesis that the oscillations occur as multiple pathways share a limited resource which we equate to the number of available ribosomes. We initially explore a single-protein model with a constraint equation governing the total resource available to the cell.

Persistent homology of coarse-grained state-space networks.

This work is dedicated to the topological analysis of complex transitional networks for dynamic state detection. Transitional networks are formed from time series data and they leverage graph theory tools to reveal information about the underlying dynamic system. However, traditional tools can fail to summarize the complex topology present in such graphs.

Detecting bifurcations in dynamical systems with CROCKER plots.

Existing tools for bifurcation detection from signals of dynamical systems typically are either limited to a special class of systems or they require carefully chosen input parameters and a significant expertise to interpret the results. Therefore, we describe an alternative method based on persistent homology-a tool from topological data analysis-that utilizes Betti numbers and CROCKER plots. Betti numbers are topological invariants of topological spaces, while the CROCKER plot is a coarsened but easy to visualize data representation of a one-parameter varying family of persistence barcodes.

Extraspinal findings prevalence and clinical significance in 4250 lumbar spine MRI exams.

To assess extraspinal findings (ESFs) prevalence in lumbar spine MRI, including clinically significant findings using a systematic approach, and to determine their reporting rate. Lumbar spine MRI scans were retrospectively reviewed over 18 months by two radiologists. Reading discrepancies were resolved by consensus.

Low-cost double pendulum for high-quality data collection with open-source video tracking and analysis.

The double pendulum is a system that manifests fascinating non-linear behavior. This made it a popular tool in academic settings for illustrating the intricate response of a seemingly simple physical apparatus, or to validate tools for studying nonlinear phenomena. In addition, the double pendulum is also widely used in several modeling applications including robotics and human locomotion analysis.

On the automatic parameter selection for permutation entropy.

Permutation Entropy (PE) is a cost effective tool for summarizing the complexity of a time series. It has been used in many applications including damage detection, disease forecasting, detection of dynamical changes, and financial volatility analysis. However, to successfully use PE, an accurate selection of two parameters is needed: the permutation dimension n and embedding delay τ.

Persistent homology of complex networks for dynamic state detection.

In this paper we develop an alternative topological data analysis (TDA) approach for studying graph representations of time series of dynamical systems. Specifically, we show how persistent homology, a tool from TDA, can be used to yield a compressed, multi-scale representation of the graph that can distinguish between dynamic states such as periodic and chaotic behavior. We show the approach for two graph constructions obtained from the time series.

Variability in Glycemic Control with Temperature Transitions during Therapeutic Hypothermia.

Purpose: Patients treated with therapeutic hypothermia (TH) and continuous insulin may be at increased risk of hyperglycemia or hypoglycemia, particularly during temperature transitions. This study aimed to evaluate frequency of glucose excursions during each phase of TH and to characterize glycemic control patterns in relation to survival.

Methods: Patients admitted to a tertiary care hospital for circulatory arrest and treated with both therapeutic hypothermia and protocol-based continuous insulin between January 2010 and June 2013 were included.

A 58-Year-Old Female with Progressive Cough and Right Shoulder Pain.

Cavitary pneumonia in immunocompromised patients is a challenging entity. Establishing accurate diagnosis and starting effective antibiotics are essential steps towards improving outcome. A 58-year-old stem cell transplant patient was admitted to the hospital with necrotizing pneumonia caused by nocardia.

Epidemiological characteristics, hospital course and outcome of snakebite victims in West Texas.

Introduction: Numerous snakebites are reported every spring and summer in the United States especially in the Southwestern part of the country. This is usually associated with significant morbidity but fatalities are rare. Most victims are male and the majority of bites are on the extremities.

The yield of stool testing in hospital-onset diarrhea: Has evidence changed practice?

Introduction: Aside from examination for Clostridium difficile, the yield of stool testing in hospital-onset diarrhea is poor. Clinical practice guidelines discourage overzealous stool testing in patients with diarrhea that develops after the third hospital day. However, the adoption of this recommendation into clinical practice is limited.

A 47-year-old stem cell transplant recipient with fever, cough and chest pain.

Infections and malignancies are among the most serious complications that follow organ or stem cell transplantation. They may have a mild course, and nonspecific and overlapping manifestations. The present article describes a case of symptomatic nodular pulmonary disease that complicated hematopoietic stem cell transplantation.

Staphylococcus lugdunensis gluteal abscess in a patient with end stage renal disease on hemodialysis.

A 57-year-old end stage renal disease patient on hemodialysis (HD) presented with sepsis secondary to right buttock abscess and overlying cellulitis. She was started on broad-spectrum antibiotic therapy and underwent incision and drainage with marked improvement. Her cultures grew methicillin-resistant Staphylococcus lugdunensis.

Cardiovascular Complications of HIV-Associated Immune Dysfunction.

Prolonged survival in HIV infection is accompanied by an increased frequency of non-HIV-related comorbidities. It is suggested that cardiovascular diseases (CVD) occur earlier among HIV-positive patients compared with HIV-negative patients, and at a higher rate. Several factors have been proposed which can be categorized into traditional and nontraditional risk factors.

Round pneumonia in an elderly woman.

We describe a case of pneumococcal round pneumonia in an elderly smoker and it demonstrates the role of inflammatory biomarkers and follow-up imaging in ruling out more ominous diagnoses.