Race in California's prison fire camps for men: prison politics, space, and the racialization of everyday life.

The vast majority of social scientists agree that race is "socially constructed." Yet many scholars of punishment and prisons still treat race as static, self-evident categories. One result is that not enough is known about the production, meanings, and consequences of race as experienced by prisoners and those who guard and manage them. The author's research on California's prison fire camps uncovers the micro-level ways in which race is performed and imbued with meaning; he reveals how racial understandings color people and settings. One puzzle is that prisoners in California's fire camps will fight natural disasters side by side, sharing water and provisions, but separate into racial groups when in the camp itself. In part to answer this (and in part to develop better understandings of race and prisons more generally), the author unpacks the variegated nature of punishment and the spatialization of race and advocates for research that is faithful to the constructivist framework.

Real-time human-robot interaction underlying neurorobotic trust and intent recognition.

In the past three decades, the interest in trust has grown significantly due to its important role in our modern society. Everyday social experience involves "confidence" among people, which can be interpreted at the neurological level of a human brain. Recent studies suggest that oxytocin is a centrally-acting neurotransmitter important in the development and alteration of trust. Its administration in humans seems to increase trust and reduce fear, in part by directly inhibiting the amygdala. However, the cerebral microcircuitry underlying this mechanism is still unknown. We propose the first biologically realistic model for trust, simulating spiking neurons in the cortex in a real-time human-robot interaction simulation. At the physiological level, oxytocin cells were modeled with triple apical dendrites characteristic of their structure in the paraventricular nucleus of the hypothalamus. As trust was established in the simulation, this architecture had a direct inhibitory effect on the amygdala tonic firing, which resulted in a willingness to exchange an object from the trustor (virtual neurorobot) to the trustee (human actor). Our software and hardware enhancements allowed the simulation of almost 100,000 neurons in real time and the incorporation of a sophisticated Gabor mechanism as a visual filter. Our brain was functional and our robotic system was robust in that it trusted or distrusted a human actor based on movement imitation.

Relationship Between Time of First Publication and Subsequent Publication Success Among Non-PhD Physician-Scientists.

BACKGROUND: Studies have shown that publication of work during medical school and residency is associated with higher numbers of later publications and citations of published research. However, it is unknown whether this association exists for non-PhD physician-scientists and whether the association persists later into their careers. METHODS: We extracted publication records from the curricula vitae (CVs) of 102 corresponding authors of articles published in 2008 in the New England Journal of Medicine and JAMA, and obtained those authors' citation records from Web of Science. We used regression models to examine the association between time of first publication and later publication and citation rates for the entire postgraduate career and a recent 2-year period. RESULTS: After adjusting for time since medical school graduation, sex, location of medical school (United States or not United States), and additional non-PhD degrees, we found that authors who first published before graduating from medical school had a greater mean number of publications after medical school and during the period from 2006 to 2007 (164 and 28, respectively) than those who first published during the 5 years afterward (111 and 19, respectively) and those who first published more than 5 years after graduation (59 and 13, respectively). Similarly, authors who first published before graduating from medical school had a greater mean number of citations of their published work since graduation and of publications from 2006 to 2007 (4634 and 333, respectively) than those who first published during the 5 years afterward (2936 and 183, respectively) and those who first published more than 5 years after graduation (1512 and 143, respectively). CONCLUSIONS: Early publication is associated with higher numbers of publications and more citations of published research among non-PhD physician-scientists. This association persists well into a researcher's career.

"Leaning" the process of venous thromboembolism prophylaxis.

BACKGROUND: Lean principles have been used at Denver Health Medical Center since 2005 to streamline nonclinical processes. Despite allocation of significant resources, particularly the expense of low molecular weight heparin (LMWH), to prophylaxis of venous thromboembolism (VTE), the incidence of postoperative VTE was significantly worse than national benchmarks. VTE risk factors were not consistently assessed, and the prescribing of prophylaxis varied widely. Lean was employed to standardize and implement risk assessment and evidence-based VTE prophylaxis for the institution. METHODS: In a rapid improvement event, a multidisciplinary group formulated an evidence-based risk assessment tool and clinical practice guideline for VTE prophylaxis, with plans for hospitalwide implementation and monitoring. RESULTS: The effects were immediate and improved steadily with feedback to clinicians. Within six months, compliance with the standard approached 100%. One year after implementation, the use of LMWH decreased more than 60% below baseline, and the use of sequential compression devices decreased by nearly 30%. With increased use of unfractionated heparin, the cost savings on VTE prophylaxis exceeded $15,000 per month, for a total of $425,000 since implementation. Moreover, the incidence of VTE decreased markedly during the same period. By reducing VTE rates, a total cost savings of $6.2 million was estimated for the past 28 months. CONCLUSIONS: Applying Lean to the clinical management of VTE prophylaxis improved compliance with standards and saved the hospital a significant amount of money. This was achieved without compromising clinical outcomes. This experience could be replicated at other institutions.

A circuit-level model of hippocampal place field dynamics modulated by entorhinal grid and suppression-generating cells.

Hippocampal "place cells" and the precession of their extracellularly recorded spiking during traversal of a "place field" are well-established phenomena. More recent experiments describe associated entorhinal "grid cell" firing, but to date only conceptual models have been offered to explain the potential interactions among entorhinal cortex (EC) and hippocampus. To better understand not only spatial navigation, but mechanisms of episodic and semantic memory consolidation and reconsolidation, more detailed physiological models are needed to guide confirmatory experiments. Here, we report the results of a putative entorhinal-hippocampal circuit level model that incorporates recurrent asynchronous-irregular non-linear (RAIN) dynamics, in the context of recent in vivo findings showing specific intracellular-extracellular precession disparities and place field destabilization by entorhinal lesioning. In particular, during computer-simulated rodent maze navigation, our model demonstrate asymmetric ramp-like depolarization, increased theta power, and frequency (that can explain the phase precession disparity), and a role for STDP and K(AHP) channels. Additionally, we propose distinct roles for two entorhinal cell populations projecting to hippocampus. Grid cell populations transiently trigger place field activity, while tonic "suppression-generating cell" populations minimize aberrant place cell activation, and limit the number of active place cells during traversal of a given field. Applied to place-cell RAIN networks, this tonic suppression explains an otherwise seemingly discordant association with overall increased firing. The findings of this circuit level model suggest in vivo and in vitro experiments that could refute or support the proposed mechanisms of place cell dynamics and modulating influences of EC.

Effect of improving the quality of radiographic interpretation on the ability to predict pulmonary tuberculosis relapse.

RATIONALE AND OBJECTIVES: Chest radiographic findings are important for diagnosis and management of tuberculosis. The reliability of these findings is therefore of interest. We sought to describe interobserver reliability of chest radiographic findings in pulmonary tuberculosis, and to understand how the reliability of these findings might affect the utility of radiographic findings in predicting tuberculosis relapse. MATERIALS AND METHODS: Three blinded readers independently reviewed chest radiographs from a randomly selected group of 10% of HIV-seronegative subjects participating in a tuberculosis treatment trial. The three readers then arrived at a fourth, consensus radiographic interpretation. RESULTS: A total of 241 films obtained from 99 patients were reviewed. Agreement among the independent readers was very good for the findings of bilateral disease (kappa = 0.71-0.86 among readers) and cavitation (kappa = 0.66-0.73). The original interpretation was reasonably sensitive and specific (compared to the consensus interpretation) for bilateral disease, but the sensitivity for cavity decreased from 81% for the 2-month film to 47% at end of treatment (P = 0.013). Substituting the consensus interpretation for the original interpretation increased the odds ratio for the association between cavitation on early chest radiograph and subsequent tuberculosis relapse from 4.97 to 8.97. CONCLUSION: Radiographic findings were reasonably reliable between independent reviewers and the original interpretations. The original investigators, who knew the patient's clinical course, were less likely to identify cavitation on the end of treatment chest radiograph. Improving the reliability of these findings could improve the utility of chest radiographs for predicting tuberculosis relapse.

Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator.

Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading "glue" tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS.

A Component-Based Extension Framework for Large-Scale Parallel Simulations in NEURON.

As neuronal simulations approach larger scales with increasing levels of detail, the neurosimulator software represents only a part of a chain of tools ranging from setup, simulation, interaction with virtual environments to analysis and visualizations. Previously published approaches to abstracting simulator engines have not received wide-spread acceptance, which in part may be to the fact that they tried to address the challenge of solving the model specification problem. Here, we present an approach that uses a neurosimulator, in this case NEURON, to describe and instantiate the network model in the simulator's native model language but then replaces the main integration loop with its own. Existing parallel network models are easily adopted to run in the presented framework. The presented approach is thus an extension to NEURON but uses a component-based architecture to allow for replaceable spike exchange components and pluggable components for monitoring, analysis, or control that can run in this framework alongside with the simulation.

Functional polymorphism of detoxification gene NQO1 predicts intensity of empirical treatment of childhood asthma.

The management of moderate to severe childhood asthma remains empirical. Genotypic variation has been proposed as a way to tailor specific pharmaceutical regimens to individual patients. The objective of this study was to determine the factors associated with asthma treatment progression, including functional polymorphisms of phase II detoxification enzymes, demographics, and environmental factors. In a study of 120 asthmatic children cared for in a single pediatric pulmonary practice, intensity of medical treatment over the year prior was modeled as a function of null mutations of glutathione S transferase (GST) M1 and T1, ile105val variant of GSTP1, and pro187ser variant of NAD(P)H:quinone oxidoreductase 1 (NQO1). The model included demographics, medical information, and environmental factors obtained via questionnaire analyzed with multivariate logistic regression and artificial neural networks. Multivariate logistic regression with bootstrapped validation identified a polymorphic variant of NQO1 as significantly contributing to increasing the odds of receiving more aggressive medical therapy (odds ratio, 11.56; p=0.0001). Parent income and education inversely correlated with medical treatment (odds ratio, 1.50; p=0.001 and odds ratio, 0.375; p=0.002, respectively). Age and reporting restricted physical activity due to asthma also impacted medical treatment (odds ratio, 0.63; p=0.0001 and odds ratio, 5.90; p=0.004, respectively). The optimism-adjusted discriminative ability (c-index) of the model was 0.881 (close to Bayes optimum of 0.902) with 80% overall classification accuracy. Our study supports the role of NQO1 polymorphism as an important factor determining the intensity of medical therapy in asthmatic children after adjusting for significance relating to parental income and education level, age, and restricted physical activity. Asthmatic children with a functional polymorphism of NQO1 may require more intensive pharmaceutical treatment to effectively control their asthma.

Radiation dose savings for adult pulmonary embolus 64-MDCT using bismuth breast shields, lower peak kilovoltage, and automatic tube current modulation.

OBJECTIVE: The purpose of this study was to assess whether radiation dose savings using a lower peak kilovoltage (kVp) setting, bismuth breast shields, and automatic tube current modulation could be achieved while preserving the image quality of MDCT scans obtained to assess for pulmonary embolus (PE). MATERIALS AND METHODS: CT angiography (CTA) examinations were performed to assess for the presence or absence of pulmonary artery emboli using a 64-MDCT scanner with automatic tube current modulation (noise level=10 HU), two kVp settings (120 and 140 kVp), and bismuth breast shields. Absorbed organ doses were measured using anthropomorphic phantoms and metal oxide semiconductor field effect transistor (MOSFET) detectors. Image quality was assessed quantitatively as well as qualitatively in various anatomic sites of the thorax. RESULTS: Using a lower kVp (120 vs 140 kVp) and automatic tube current modulation resulted in a dose savings of 27% to the breast and 47% to the lungs. The use of a lower kVp (120 kVp), automatic tube current modulation, and bismuth shields placed directly on the anterior chest wall reduced absorbed breast and lung doses by 55% and 45%, respectively. Qualitative assessment of the images showed no change in image quality of the lungs and mediastinum when using a lower kVp, bismuth shields, or both. CONCLUSION: The use of bismuth breast shields together with a lower kVp and automatic tube current modulation will reduce the absorbed radiation dose to the breast and lungs without degradation of image quality to the organs of the thorax for CTA detection of PE.

Framework and implications of virtual neurorobotics.

Despite decades of societal investment in artificial learning systems, truly "intelligent" systems have yet to be realized. These traditional models are based on input-output pattern optimization and/or cognitive production rule modeling. One response has been social robotics, using the interaction of human and robot to capture important cognitive dynamics such as cooperation and emotion; to date, these systems still incorporate traditional learning algorithms. More recently, investigators are focusing on the core assumptions of the brain "algorithm" itself-trying to replicate uniquely "neuromorphic" dynamics such as action potential spiking and synaptic learning. Only now are large-scale neuromorphic models becoming feasible, due to the availability of powerful supercomputers and an expanding supply of parameters derived from research into the brain's interdependent electrophysiological, metabolomic and genomic networks. Personal computer technology has also led to the acceptance of computer-generated humanoid images, or "avatars", to represent intelligent actors in virtual realities. In a recent paper, we proposed a method of virtual neurorobotics (VNR) in which the approaches above (social-emotional robotics, neuromorphic brain architectures, and virtual reality projection) are hybridized to rapidly forward-engineer and develop increasingly complex, intrinsically intelligent systems. In this paper, we synthesize our research and related work in the field and provide a framework for VNR, with wider implications for research and practical applications.

Clinical hospital medicine fellowships: perspectives of employers, hospitalists, and medicine residents.

BACKGROUND: Clinical hospital medicine fellowships could accelerate the acquisition of increasingly demanding skills while enhancing esteem among subspecialty peers. We sought to determine whether medicine residents perceived such fellowships as relevant and would be willing to forgo substantial income during the training period, in the context of the perspectives of employers and practicing hospitalists. DESIGN: A series of 3 tandem nationwide cross-sectional surveys conducted over the Internet during late 2005 and early 2006. METHODS: Survey I was sent to 195 hospitalist employers identified through filtering classified advertisements. Survey II (containing Survey I results) was E-mailed by the Society of Hospital Medicine to its practicing hospitalists members. Survey III (containing results of the first 2 surveys) was E-mailed to U.S. internal medicine program directors for forwarding to their residents. RESULTS: Two-thirds of 103 employers would offer either a signing bonus or a starting salary increase of at least $10,000 to fellowship graduates (more than 20% would pay at least $20,000 more in the salary). Based on a median experience of 8 years, 91% of 101 practicing hospitalists believed that clinical fellowship could at least possibly be a favorable career move, with 58% recommending it as being a probably or strongly favorable career move. Of 279 categorical medicine residents, 44% were considering a hospital medicine career, of whom 57% would consider doing a year of clinical fellowship training if available. CONCLUSIONS: This study reveals a potentially unmet demand for clinical hospital medicine fellowship training. Further determination of need and related curricular development could be addressed under the leadership of national hospital medicine educational organizations.

Radiation dose from contemporary cardiothoracic multidetector CT protocols with an anthropomorphic female phantom: implications for cancer induction.

PURPOSE: To measure prospectively and directly both organ dose and effective dose (ED) for adult cardiac and pulmonary computed tomographic (CT) angiography by using current clinical protocols for 64-detector CT in an anthropomorphic female phantom and to estimate lifetime attributable risk of breast and lung cancer incidence on the basis of measured ED and organ dose. MATERIALS AND METHODS: Cardiac and pulmonary 64-detector CT angiography was performed by using current clinical protocols to evaluate the pulmonary veins (electrocardiographically [ECG] gated, 64 sections at 0.625-mm collimation, 120 kVp, 300 mA, 0.35-second tube rotation), native coronary arteries (ECG gated; 64 sections at 0.625 mm; 120 kVp; maximum current, 500-750 mA; minimum, 100-350 mA; 0.35-second tube rotation) and pulmonary embolus (64 sections at 1.25 mm, 140 kVp, 645 mA, 0.5-second tube rotation). Absorbed organ doses were measured by using an anthropomorphic female phantom and metal oxide semiconductor field effect transistor detectors. ED was calculated from measured organ doses and the dose-length product. RESULTS: ED for current adult cardiac and pulmonary 64-detector CT angiography protocols were 12.4-31.8 mSv. Overall, skin, breast, and esophagus and heart had the highest recorded absorbed organ doses. Relative risk for breast cancer incidence for girls and women was 1.004-1.042 for a single examination. Relative risk for lung cancer incidence for men and women was 1.005-1.076 from a single examination. CONCLUSION: EDs and organ doses from 64-detector CT are higher than those previously reported for adult cardiac and pulmonary CT angiography protocols. Risk for breast and lung cancer induction from these studies is greatest for the younger patient population.

Effective dose determination using an anthropomorphic phantom and metal oxide semiconductor field effect transistor technology for clinical adult body multidetector array computed tomography protocols.

PURPOSE: To determine the organ doses and total body effective dose (ED) delivered to an anthropomorphic phantom by multidetector array computed tomography (MDCT) when using standard clinical adult body imaging protocols. MATERIALS AND METHODS: Metal oxide semiconductor field effect transistor (MOSFET) technology was applied during the scanning of a female anthropomorphic phantom to determine 20 organ doses delivered during clinical body computed tomography (CT) imaging protocols. A 16-row MDCT scanner (LightSpeed, General Electric Healthcare, Milwaukee, Wis) was used. Effective dose was calculated as the sum of organ doses multiplied by a weighting factor determinant found in the International Commission on Radiological Protection Publication 60. Volume CT dose index and dose length product (DLP) values were recorded at the same time for the same scan. RESULTS: Effective dose (mSv) for body MDCT imaging protocols were as follows: standard chest CT, 6.80 +/- 0.6; pulmonary embolus CT, 13.7 +/- 0.4; gated coronary CT angiography, 20.6 +/- 0.4; standard abdomen and pelvic CT, 13.3 + 1.0; renal stone CT, 4.51 + 0.45. Effective dose calculated by direct organ measurements in the phantom was 14% to 37% greater than those determined by the DLP method. CONCLUSIONS: Effective dose calculated by the DLP method underestimates ED as compared with direct organ measurements for the same CT examination. Organ doses and total body ED are higher than previously reported for MDCT clinical body imaging protocols.

Simulation of networks of spiking neurons: a review of tools and strategies.

We review different aspects of the simulation of spiking neural networks. We start by reviewing the different types of simulation strategies and algorithms that are currently implemented. We next review the precision of those simulation strategies, in particular in cases where plasticity depends on the exact timing of the spikes. We overview different simulators and simulation environments presently available (restricted to those freely available, open source and documented). For each simulation tool, its advantages and pitfalls are reviewed, with an aim to allow the reader to identify which simulator is appropriate for a given task. Finally, we provide a series of benchmark simulations of different types of networks of spiking neurons, including Hodgkin-Huxley type, integrate-and-fire models, interacting with current-based or conductance-based synapses, using clock-driven or event-driven integration strategies. The same set of models are implemented on the different simulators, and the codes are made available. The ultimate goal of this review is to provide a resource to facilitate identifying the appropriate integration strategy and simulation tool to use for a given modeling problem related to spiking neural networks.

Validation of metal oxide semiconductor field effect transistor technology for organ dose assessment during CT: comparison with thermoluminescent dosimetry.

OBJECTIVE: The purposes of this study were to apply near-real-time dose-measurement technology with metal oxide semiconductor field effect transistors (MOSFETs) to the assessment of organ dose during CT and to validate the method in comparison with the thermoluminescent dosimeter (TLD) method. MATERIALS AND METHODS: Dosimetry measurements were performed in two ways, one with TLDs and the other with MOSFETs. Twenty organ locations were selected in an adult anthropomorphic female phantom. High-sensitivity MOSFET dosimeters were used. For the reference standard, TLDs were placed in the same organ locations as the MOSFETs. Both MOSFET and TLD detectors were calibrated with an X-ray beam equivalent in quality to that of a commercial CT scanner (half-value layer, approximately 7 mm Al at 120 kVp). Organ dose was determined with a scan protocol for pulmonary embolus studies on a 4-MDCT scanner. RESULTS: Measurements for selected organ doses and the percentage difference for TLDs and MOSFETs, respectively, were as follows: thyroid (0.34 cGy, 0.31 cGy, -8%), middle lobe of lung (2.4 cGy, 3.0 cGy, +26%), bone marrow of thoracic spine (2.2 cGy, 2.5 cGy, +11%), stomach (1.0 cGy, 0.93 cGy, -6%), liver (2.5 cGy, 2.6 cGy, +6%), and left breast (3.0 cGy, 2.9 cGy, -1%). Bland-Altman analysis showed that the MOSFET results agreed with the TLD results (bias, 0.042). CONCLUSION: We found good agreement between the results with the MOSFET and TLD methods. Near-real-time CT organ dose assessment not previously feasible with TLDs was achieved with MOSFETs. MOSFET technology can be used for protocol development in the rapidly changing MDCT scanner environment, in which organ dose data are extremely limited.