QUIC Transport and Dispersion Modeling of Vehicle Emissions in Cities for Better Public Health Assessments

The Quick Urban and Industrial Complex (QUIC) plume modeling system is used to explore how the transport and dispersion of vehicle emissions in cities are impacted by the presence of buildings. Using downtown Philadelphia as a test case, notional vehicle emissions of gases and particles are specified as line source releases on a subset of the east-west and north-south streets. Cases were run in flat terrain and with 3D buildings present in order to show the differences in the model-computed outdoor concentration fields with and without buildings present. The QUIC calculations show that buildings result in regions with much higher concentrations and other areas with much lower concentrations when compared to the flat-earth case. On the roads with vehicle emissions, street-level concentrations were up to a factor of 10 higher when buildings were on either side of the street as compared to the flat-earth case due to trapping of pollutants between buildings. However, on roads without vehicle emissions and in other open areas, the concentrations were up to a factor of 100 times smaller as compared to the flat earth case because of vertical mixing of the vehicle emissions to building height in the cavity circulation that develops on the downwind side of unsheltered buildings. QUIC was also used to calculate infiltration of the contaminant into the buildings. Indoor concentration levels were found to be much lower than outdoor concentrations because of deposition onto indoor surfaces and particulate capture for buildings with filtration systems. Large differences in indoor concentrations from building to building resulted from differences in leakiness, air handling unit volume exchange rates, and filter type and for naturally ventilated buildings, whether or not the building was sheltered from the prevailing wind by a building immediately upwind.

Fecal Metabolome in Hmga1 Transgenic Mice with Polyposis: Evidence for Potential Screen for Early Detection of Precursor Lesions in Colorectal Cancer

Because colorectal cancer (CRC) remains a leading cause of cancer mortality worldwide, more accessible screening tests are urgently needed to identify early stage lesions. We hypothesized that highly sensitive, metabolic profile analysis of stool samples will identify metabolites associated with early stage lesions and could serve as a noninvasive screening test. We therefore applied traveling wave ion mobility mass spectrometry (TWIMMS) coupled with ultraperformance liquid chromatography (UPLC) to investigate metabolic aberrations in stool samples in a transgenic model of premalignant polyposis aberrantly expressing the gene encoding the high mobility group A (Hmga1) chromatin remodeling protein. Here, we report for the first time that the fecal metabolome of Hmga1 mice is distinct from that of control mice and includes metabolites previously identified in human CRC. Significant alterations were observed in fatty acid metabolites and metabolites associated with bile acids (hypoxanthine xanthine, taurine) in Hmga1 mice compared to controls. Surprisingly, a marked increase in the levels of distinctive short, arginine-enriched, tetra-peptide fragments was observed in the transgenic mice. Together these findings suggest that specific metabolites are associated with Hmga1-induced polyposis and abnormal proliferation in intestinal epithelium. Although further studies are needed, these data provide a compelling rationale to develop fecal metabolomic analysis as a noninvasive screening tool to detect early precursor lesions to CRC in humans.

Using Interdisciplinary Workgroups to Educate Surgery Residents in Systems-Based Practice

BACKGROUND

Meaningful education of residents in systems-based practice is notoriously challenging, despite its recognition as 1 of the 6 Accreditation Council for Graduate Medical Education core competencies. To address this challenge, surgery residents and other members of the health care team were organized into interdisciplinary workgroups that were tasked with developing solutions to "systems issues" confronted on a daily basis. The project's goals included providing more meaningful, hands-on educational experience for residents in system-based practice, while also generating practical solutions to workflow issues through interprofessional collaboration.

PROJECT DESIGN

Project participants included all surgery residents at the University of Virginia in Charlottesville, VA, as well as surgical health care professionals across all disciplines. Participants were organized into workgroups. Over the course of 3 sessions, each of 1-hour, each workgroup identified commonly encountered systems issues, chose 1 issue to address, and determined an implementable solution for this issue. In total, 140 participants were divided among 13 workgroups.

PROJECT EXECUTION

Workgroup topics ranged from improving paging etiquette to standardizing interdisciplinary communication. In total, 9 of the 13 proposals have been piloted or fully implemented as standard practice at our institution, either within a single unit or over the entire health system.

DISCUSSION

This project demonstrates an innovative approach toward resident education in system-based practice, providing residents with a hands-on experience in problem solving from a systems perspective. These interdisciplinary workgroups generated effective solutions to issues that were meaningful to frontline health care providers. Interdisciplinary collaboration within the workgroups served as a valuable team-building exercise to improve relations between the disciplines. This project can serve as a model for other institutions desiring meaningful education in the Accreditation Council for Graduate Medical Education competency of systems-based practice.

Anti-stromal treatment together with chemotherapy targets multiple signalling pathways in pancreatic adenocarcinoma

Stromal targeting for pancreatic ductal adenocarcinoma (PDAC) is rapidly becoming an attractive option, due to the lack of efficacy of standard chemotherapy and increased knowledge about PDAC stroma. We postulated that the addition of stromal therapy may enhance the anti-tumour efficacy of chemotherapy. Gemcitabine and all-trans retinoic acid (ATRA) were combined in a clinically applicable regimen, to target cancer cells and pancreatic stellate cells (PSCs) respectively, in 3D organotypic culture models and genetically engineered mice (LSL-Kras(G12D) (/+) ;LSL-Trp53(R172H) (/+) ;Pdx-1-Cre: KPC mice) representing the spectrum of PDAC. In two distinct sets of organotypic models as well as KPC mice, we demonstrate a reduction in cancer cell proliferation and invasion together with enhanced cancer cell apoptosis when ATRA is combined with gemcitabine, compared to vehicle or either agent alone. Simultaneously, PSC activity (as measured by deposition of extracellular matrix proteins such as collagen and fibronectin) and PSC invasive ability were both diminished in response to combination therapy. These effects were mediated through a range of signalling cascades (Wnt, hedgehog, retinoid, and FGF) in cancer as well as stellate cells, affecting epithelial cellular functions such as epithelial-mesenchymal transition, cellular polarity, and lumen formation. At the tissue level, this resulted in enhanced tumour necrosis, increased vascularity, and diminished hypoxia. Consequently, there was an overall reduction in tumour size. The enhanced effect of stromal co-targeting (ATRA) alongside chemotherapy (gemcitabine) appears to be mediated by dampening multiple signalling cascades in the tumour-stroma cross-talk, rather than ablating stroma or targeting a single pathway. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Central Nervous System and Head and Neck Histiocytoses: A Comprehensive Review on the Spectrum of Imaging Findings

The histiocytoses are a rare group of varied but related disorders characterized by abnormal tissue proliferation of macrophages and dendritic cells within tissues. The purpose of this article was to review the imaging findings in patients presenting with CNS and with head and neck manifestations of these disorders. Histiocytoses include but are not limited to Rosai-Dorfman disease, Erdheim Chester disease, Langerhans cell histiocytosis, histiocytic sarcoma, and juvenile xanthogranuloma. A review of the literature was performed to determine the sites of disease involvement. This article includes the demographics, histopathologic criteria for diagnosis, and imaging features of these histiocytoses, and describes the manifestations in locations known to harbor disease: intraaxial and extra-axial intracranial regions, the calvaria, skull base, hypothalamopituitary axis, orbits, paranasal sinuses, spine, and the head and neck region. Histiocytoses have variable imaging appearances in the CNS and in the head and neck region, and radiologists should be aware of the spectrum of findings to avoid mistaking them for other disease processes.

Learning Objective

To understand the general pathophysiology, clinical presentation, and typical imaging characteristics of the most common histiocytoses; comprehend the morphologic and immunohistochemical characteristics of these histiocytoses and the hallmark findings on pathology; and be able to differentiate between these disorders based on their most common presentations.

Consumer adoption of mobile banking in Jordan

Purpose

– The purpose of this paper is to propose and examine a conceptual model that best explains the key factors influencing Jordanian customers ' intention to adopt mobile banking (MB).

Design/methodology/approach

– The proposed conceptual model was based on the Technology Acceptance Model (TAM). This was extended by adding perceived risk and self-efficacy as an external factors. Structural equation modelling (SEM) was conducted to analyse the data collected from the field survey questionnaires administered to a convenience sample of Jordanian banking customers.

Findings

– The results showed that behavioural intention is significantly influenced by perceived usefulness, perceived ease of use, and perceived risk.

Research limitations/implications

– Practical and theoretical implications for both Jordanian banks and researchers in the MB context are also discussed in the concluding section.

Originality/value

– MB-related issues are yet to be examined empirically in the Jordanian context. This submission has attempted to fill this gap by empirically examining some of the important factors influencing the adoption of MB from the Jordanian customers’ perspective.

The prehospital and hospital costs of emergency care for frequent ED patients

INTRODUCTION

Frequent emergency department (ED) use has been identified as a cause of ED overcrowding and increasing health care costs. Studies have examined the expense of frequent patients (FPs) to hospitals but have not added the cost Emergency Medical Services (EMS) to estimate the total cost of this pattern of care.

METHODS

Data on 2012 ED visits to a rural Level I Trauma Center and public safety net hospital were collected through a deidentified patient database. Transport data and 2012 Medicare Reimbursement Schedules were used to estimate the cost of EMS transport. Health information, outcomes, and costs were compared to find differences between the FP and non-FP group.

RESULTS

This study identified 1242 FPs who visited the ED 5 or more times in 2012. Frequent patients comprised 3.25% of ED patients but accounted for 17% of ED visits and 13.7% of hospital costs. Frequent patients had higher rates of chronic disease, severity scores, and mortality. Frequent patients arrived more often via ambulance and accounted for 32% of total transports at an estimated cost of $2.5-$3.2 million. Hospital costs attributable to FPs were $29.1 million, bringing the total cost of emergency care to $31.6-$32.3 million, approximately $25,000 per patient.

CONCLUSIONS

This study demonstrates that the inclusion of a prehospital cost estimate adds approximately 10% to the cost of care for the FP population. In addition to improving care for a sick population of patients, programs that reduce frequent EMS and ED use have the potential to produce a favorable cost benefit to communities and health systems.

Examining the Role of Social Influence, Usefulness and Ease of Use for Determining the Mandatory Use of a Human Resource Information System in the Context of Saudi Ministries

This paper examines whether social influence (SI), perceived usefulness (PU) and ease of use (EU) play an important role towards encouraging the mandatory use of a human resource information system (HRIS) in Saudi ministries. The review of the existing literature indicates that no previous research has examined the mandatory use of HRIS in the Saudi context. Thus, this study has developed a conceptual model by integrating (SI) with factors from the technology acceptance model (TAM) to investigate factors affecting the use and user satisfaction of HRIS. The structure equation modelling technique was employed to test the proposed conceptual model by utilising a questionnaire-based survey data collected from a total of 195 respondents. The findings from this study suggest that (SI) exerts both a direct and indirect effect for encouraging employees to use HRIS. The findings also suggest that TAM factors (i.e. PU and EU) had a significant effect on both the use of the system and user satisfaction.

Ammonia gas transport and reactions in unsaturated sediments: implications for use as an amendment to immobilize inorganic contaminants

Use of gas-phase amendments for in situ remediation of inorganic contaminants in unsaturated sediments of the vadose zone may be advantageous, but there has been limited development and testing of gas remediation technologies. Treatment with ammonia gas has a potential for use in treating inorganic contaminants (such as uranium) because it induces a high pore-water pH, causing mineral dissolution and subsequent formation of stable precipitates that decrease the mobility of some contaminants. For field application of this treatment, further knowledge of ammonia transport in porous media and the geochemical reactions induced by ammonia treatment is needed. Laboratory studies were conducted to support calculations needed for field treatment design, to quantify advective and diffusive ammonia transport in unsaturated sediments, to evaluate inter-phase (gas/sediment/pore water) reactions, and to study reaction-induced pore-water chemistry changes as a function of ammonia delivery conditions, such as flow rate, gas concentration, and water content. Uranium-contaminated sediment was treated with ammonia gas to demonstrate U immobilization. Ammonia gas quickly partitions into sediment pore water and increases the pH up to 13.2. Injected ammonia gas advection front movement can be reasonably predicted by gas flow rate and equilibrium partitioning. The ammonia gas diffusion rate is a function of the water content in the sediment. Sodium, aluminum, and silica pore-water concentrations increase upon exposure to ammonia and then decline as aluminosilicates precipitate when the pH declines due to buffering. Up to 85% of the water-leachable U was immobilized by ammonia treatment.

Phase II trial of everolimus and erlotinib in patients with platinum-resistant recurrent and/or metastatic head and neck squamous cell carcinoma

BACKGROUND

Enhanced phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway is one of the key adaptive changes accounting for epidermal growth factor receptor (EGFR) inhibitor-resistant growth in head and neck squamous cell carcinoma (HNSCC). We designed a phase II clinical trial of EGFR tyrosine kinase inhibitor (TKI), erlotinib, in association with the mTOR inhibitor, everolimus, based on the hypothesis that the downstream effects of Akt through inhibition of mTOR may enhance the effectiveness of the EGFR-TKI in patients with recurrent/metastatic HNSCC.

PATIENTS AND METHODS

Patients with histologically or cytologically confirmed platinum-resistant HNSCC received everolimus 5 mg and erlotinib 150 mg daily orally until disease progression, intolerable toxicity, investigator or patient decision. Cytokines and angiogenic factors profile, limited mutation analysis and p16 immunohistochemistry status were included in the biomarker analysis.

RESULTS

Of the 35 assessable patients, 3 (8%) achieved partial response at 4 weeks, 1 confirmed at 12 weeks; overall response rate at 12 weeks was 2.8%. Twenty-seven (77%) patients achieved disease stabilization at 4 weeks, 11 (31%) confirmed at 12 weeks. Twelve-week progression-free survival (PFS) was 49%, median PFS 11.9 weeks and median overall survival (OS) 10.25 months. High neutrophil gelatinase lipocalin (P = 0.01) and vascular endothelial growth factor (VEGF) (P = 0.04) plasma levels were significantly associated with worse OS.

CONCLUSIONS

The combination of erlotinib and everolimus did not show significant benefit in unselected patients with platinum-resistant metastatic HNSCC despite a manageable toxicity profile. Markers of tumor invasion and hypoxia identify a group of patients with particularly poor prognosis.

CLINICAL TRIAL NUMBER

NCT00942734.

Characterizing metabolic changes in human colorectal cancer

Colorectal cancer (CRC) remains a leading cause of cancer death worldwide, despite the fact that it is a curable disease when diagnosed early. The development of new screening methods to aid in early diagnosis or identify precursor lesions at risk for progressing to CRC will be vital to improving the survival rate of individuals predisposed to CRC. Metabolomics is an advancing area that has recently seen numerous applications to the field of cancer research. Altered metabolism has been studied for many years as a means to understand and characterize cancer. However, further work is required to establish standard procedures and improve our ability to identify distinct metabolomic profiles that can be used to diagnose CRC or predict disease progression. The present study demonstrates the use of direct infusion traveling wave ion mobility mass spectrometry to distinguish metabolic profiles from CRC samples and matched non-neoplastic epithelium as well as metastatic and primary tumors at different stages of disease (T1-T4). By directly infusing our samples, the analysis time was reduced significantly, thus increasing the speed and efficiency of this method compared to traditional metabolomics platforms. Partial least squares discriminant analysis was used to visualize differences between the metabolic profiles of sample types and to identify the specific m/z features that led to this differentiation. Identification of the distinct m/z features was made using the human metabolome database. We discovered alterations in fatty acid biosynthesis and oxidative, glycolytic, and polyamine pathways that distinguish tumors from non-malignant colonic epithelium as well as various stages of CRC. Although further studies are needed, our results indicate that colonic epithelial cells undergo metabolic reprogramming during their evolution to CRC, and the distinct metabolites could serve as diagnostic tools or potential targets in therapy or primary prevention. Graphical Abstract Colon tissue biopsy samples were collected from patients after which metabolites were extracted via sonication. Two-dimensional data were collected via IMS in tandem with MS (IMMS). Data were then interpreted statistically via PLS-DA. Scores plots provided a visualization of statistical separation and groupings of sample types. Loading plots allowed identification of influential ion features. Lists of these features were exported and analyzed for specific differences. Direct comparisons of the ion features led to the identification and comparative analyses of candidate biomarkers. These differences were then expressed visually in charts and tables.

The unified theory of acceptance and use of technology (UTAUT): a literature review

Purpose

– The purpose of this paper is to perform a systematic review of articles that have used the unified theory of acceptance and use of technology (UTAUT).

Design/methodology/approach

– The results produced in this research are based on the literature analysis of 174 existing articles on the UTAUT model. This has been performed by collecting data including demographic details, methodological details, limitations, and significance of relationships between the constructs from the available articles based on the UTAUT.

Findings

– The findings indicated that general purpose systems and specialized business systems were examined in the majority of the articles using the UTAUT. The analysis also indicated that cross-sectional approach, survey methods, and structural equation modelling analysis techniques were the most explored research methodologies whereas SPSS was found to be the largely used analysis tools. Moreover, the weight analysis of independent variables indicates that variables such as performance expectancy and behavioural intention qualified for the best predictor category. Moreover, the analysis also suggested that single subject or biased sample as the most explored limitation across all studies.

Research limitations/implications

– The search activities were centered on occurrences of keywords to avoid tracing a large number of publications where these keywords might have been used as casual words in the main text. However, we acknowledge that there may be a number of studies, which lack keywords in the title, but still focus upon UTAUT in some form.

Originality/value

– This is the first research of its type which has extensively examined the literature on the UTAUT and provided the researchers with the accumulative knowledge about the model.

HMGA1 drives metabolic reprogramming of intestinal epithelium during hyperproliferation, polyposis, and colorectal carcinogenesis

Although significant progress has been made in the diagnosis and treatment of colorectal cancer (CRC), it remains a leading cause of cancer death worldwide. Early identification and removal of polyps that may progress to overt CRC is the cornerstone of CRC prevention. Expression of the High Mobility Group A1 (HMGA1) gene is significantly elevated in CRCs as compared with adjacent, nonmalignant tissues. We investigated metabolic aberrations induced by HMGA1 overexpression in small intestinal and colonic epithelium using traveling wave ion mobility mass spectrometry (TWIMMS) in a transgenic model in which murine Hmga1 was misexpressed in colonic epithelium. To determine if these Hmga1-induced metabolic alterations in mice were relevant to human colorectal carcinogenesis, we also investigated tumors from patients with CRC and matched, adjacent, nonmalignant tissues. Multivariate statistical methods and manual comparisons were used to identify metabolites specific to Hmga1 and CRC. Statistical modeling of data revealed distinct metabolic patterns in Hmga1 transgenics and human CRC samples as compared with the control tissues. We discovered that 13 metabolites were specific for Hmga1 in murine intestinal epithelium and also found in human CRC. Several of these metabolites function in fatty acid metabolism and membrane composition. Although further validation is needed, our results suggest that high levels of HMGA1 protein drive metabolic alterations that contribute to CRC pathogenesis through fatty acid synthesis. These metabolites could serve as potential biomarkers or therapeutic targets.

Pdx1 (GFP/w) mice for isolation, characterization, and differentiation of pancreatic progenitor cells

It is well known that human cells are diverse with respect to their epigenome, transcriptome, and proteome. In the context of regenerative medicine, it is important for the transplanted cells or tissues to faithfully recapitulate their intended tissue type in each of these respects. Whether the cells chosen for such an application are embryonic, postnatal, or induced pluripotent stem cells, the transplanted product must behave in a predictable and reliable manner to be a safe and effective treatment option. Irrespective of the choice of cells used in such an application, the characterization and understanding of the developmental cues responsible for establishing and maintaining the desired cell phenotype are essential.Animal models are extremely important in understanding the development of a specific tissue, which can then be subsequently extrapolated to human studies. Generation of transgenic animal models with whole-body gene knockout, conditional knockout, constitutive fluorescent gene reporters, and Cre-Lox-based conditional and lineage reporters has revolutionized the field of developmental biology. An intrinsically complex network of the actions and interactions of the multitude of different signalling cascades is required for development. A thorough understanding of such networks, gained through studies on transgenic animal models, is essential for the development of the techniques necessary to reliably differentiate a given stem or progenitor cell population into a specific cell type, such as an islet-like, insulin-producing cell aggregate.In this chapter, we describe the use of GFP (green fluorescent protein)-based reporter mice for isolation of cells of choice, analyzing gene expression in those cells as well as their use for screening signalling molecules to understand their effect on differentiation.

Extended sacropelvic resection for locally recurrent rectal cancer: can it be done safely and with good oncologic outcomes?

BACKGROUND

A multimodality approach to patients with locally recurrent rectal cancer that includes surgery is associated with a significant survival advantage when tumor-free margins are achieved. Patients with advanced tumors will require extended sacropelvic resection to optimize oncologic outcomes.

OBJECTIVE

The aim of this study was to assess the safety, feasibility, and oncologic outcomes of extended sacropelvic resection for locally recurrent rectal cancer at our institution.

DESIGN

A retrospective review identified 406 patients who had surgery for locally recurrent rectal cancer between 1997 and 2007. From this group, all patients who underwent a curative-intent sacropelvic resection were analyzed.

SETTINGS

This investigation was conducted at an academic tertiary referral center.

PATIENTS

Thirty patients (24 male) were identified. Median age was 59 years (range, 25-84). Operations were performed for a first local recurrence (n = 24), a second recurrence (n = 5) and for a third recurrence (n = 1).

INTERVENTIONS

Twenty-six patients underwent neoadjuvant radiation, and 20 received intraoperative radiation therapy. All patients underwent extended sacropelvic resection.

MAIN OUTCOME MEASURES

The primary outcomes measured were early (<30 days) and late (>30 days) surgical complications. Overall and disease-free survivals were estimated by using the Kaplan-Meier technique.

RESULTS

Margin-negative resection was achieved in 93%. The most proximal level of spinal transection was the fourth lumbar space, and 4 patients underwent lower extremity amputation. There was no mortality, and early morbidity was seen in 76%. Median follow-up was 2.7 years (range, 2 months to 10.8 years). Overall survival at 2 and 5 years was 86% and 46%. Disease-free survival at 2 and 5 years was 79% and 43%.

LIMITATIONS

This study was limited by its retrospective nature and the limited number of patients.

CONCLUSIONS

We found extended sacropelvic resection for locally recurrent rectal cancer to be feasible and safe with overall and disease-free survival rates in comparison with survival rates seen in patients undergoing nonsacropelvic resections for locally recurrent rectal cancer.