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Periodic updates to small caliber weapon systems and projectiles used in military and law enforcement have resulted in consistently increasing material penetration capabilities. With each new generation, ballistics technology outpaces the lifecycle replacement of live-fire training facilities. For this reason, it is necessary to develop and maintain constitutive material models for use in analyzing the effects new threats will have on existing facilities and for designing new training facilities using numerical methods. This project utilizes material testing data to characterize cellular concretes used in the construction of live-fire training facilities with a 13-parameter Holmquist-Johnson-Cook (HJC) concrete constitutive model. Various statistical tools are used in this analysis to successfully describe the importance of each model parameter and quantify their uncertainty. First, Bayesian linear regression was used to calibrate the parameters in the strength and pressure components of the HJC material model given testing data of cellular concrete. These uncertain parameters were then used to construct computer simulations of penetration and perforation experiments that were previously conducted by Collard and Lanham. Then, Latin Hypercube Sampling of the parameter space was used to generate training data for a Gaussian Process surrogate model of the computer simulation. Using the surrogate model, a global variance-based sensitivity analysis of the material model was completed by computing main and total effect Sobol indices. Finally, a Bayesian calibration of the computer simulation based on the physical experiments was conducted to fully characterize the stochastic behavior of the material subjected to perforation impacts. These approaches can be used to inform decision makers about the potential risk associated with existing facilities and by designers of future live fire training facilities.

The effect of partition walls and non-structural elements on the dynamic response of floors is still not well understood, and there is a need for vibration testing of floors at various stages of construction. The best way to shed some light on the effect of non-structural components is to test additional floors (preferably the same floor) before and after the installation of non-structural elements and compare the dynamic properties. For that purpose, the authors conducted vibration testing on a building floor under construction at various stages of fit-out to quantify the effects of various non-structural elements on the vibration response. An elevated floor of a steel-framed building in the Southeastern United States was tested: the first test was performed for the bare slab conditions with minimal non-structural elements, while the second test was conducted after the installation of non-structural components and in the presence of various construction materials spread over the test floor. The modal tests were conducted by applying measured dynamic forces using an electrodynamic shaker while accelerations were measured at critical locations on the slab. The measurements were post-processed to determine the frequency response functions, which provided general information on the dynamic response. The selection of the test points and excitation functions were primarily to extract maximum data regarding the performance of non-structural elements rather than as part of a standard vibration serviceability assessment of the floor structure. The modal tests were repeated after the installation of non-structural components, electrical and mechanical ductwork, to determine their effect on the vibration characteristics of the floor. The resulting frequency response functions were compared for each condition, and finite element models were created to represent each test condition. As a result, the installation of non-structural components was observed to influence the dynamic response of the floor. Combined with the other test data in the literature, the results of the experimental testing presented in this paper might lead to more effective modeling techniques and provide guidance as to their inclusion into analytical models.

We present a case of a 70-year-old Caucasian woman with multisystem granulomatous disease involving her lungs, bones and lymph nodes. The patient initially presented with cervical lymphadenopathy and subsequently developed progressive breathlessness. Imaging revealed extensive mediastinal, hilar and intra-abdominal lymphadenopathy as well as bilateral pulmonary parenchymal infiltrates. Lymph node and lung biopsy confirmed non-necrotising granulomatous inflammation while a BAL showed scanty growth of Cryptococcus neoformans and moderate growth of Staphylococcus aureus. The patient received intravenous ceftriaxone and had a good response to treatment. She also completed 3 months of oral fluconazole. Although a diagnosis of sarcoidosis was considered most likely, the patient was not initially started on systemic corticosteroids due to concern around possible infection and initial response to antimicrobials. However, her exercise tolerance gradually deteriorated. A craniofacial CT revealed multiple lytic lesions involving the skull and visualised cervical spine. Biopsy of a clivus lesion revealed non-necrotising granulomatous inflammation while fungal cultures and histopathological stains were negative. The patient was diagnosed with widespread sarcoidosis and she was initiated on prednisolone and methotrexate which led to marked clinical and radiological improvement.

In this paper, the accuracies of four well-established floor vibration evaluation methods developed over the last couple of decades are investigated by comparing predictions with observed acceptability of each bay. A large database of steel-framed floors subjected to walking excitation is used for the evaluations and comparisons. Detailed comparisons have been made among the methods of the American Institute of Steel Construction (AISC) Design Guide 11 Chapter 4 Method; Steel Construction Institute (SCI) P354 Simplified Method; Steel Construction Institute (SCI) P354 Vibration Dose Values; and Human Induced Vibration of Steel Structures (HIVOSS) Method. The floor bay database is based on data collected from real buildings and it contains 22 satisfactory and 28 unsatisfactory bays, a total of 50 bays.

It is sometimes necessary to locate the source of machinery-induced vibrations in buildings when the generated vibration exceeds the acceptable limits. The objective of this study is to localize stationary source of vibration using floor vibration measurements with the steered response power (SRP) method. While this method has been used in microphone array processing and acoustic imaging systems, this paper describes the first application of this method to surface wave vibrations in structures. Source locations are derived from shifted and summed version of received signals by accelerometers to search and find the maximum likelihood of source location. Similar to the time difference of arrival (TDOA) method, the accuracy of the estimate is degraded by the frequency dependent propagation speed and attenuation of concrete floor, which lead to changes in the shape of the received signals. However, the SRP method is more robust than TDOA. Additional processing steps will be applied to reduce the effect of the aforementioned issues. The accuracy of the SRP method is validated through series of experiments in a building. To estimate the wave propagation speed, which is needed for SRP method, cross-correlation is used to compute delays between received signals. The accuracy of this method depends on the location of the source on the bay. Experiments showed an average error of 1 m or less for a single bay with a size of approximately 13.4 by 8.2 m when the source is located at mid bay. The results for SRP method as well as its advantages and shortcomings are discussed.

Walking-induced loads on office floors can generate unwanted vibrations. The current multi-person loading models are limited since they do not take into account nondeterministic factors such as pacing rates, walking paths, obstacles in walking paths, busyness of floors, stride lengths, and interactions among the occupants. This study proposes a novel video-vibration monitoring system to investigate the complex human walking patterns on floors. The system is capable of capturing occupant movements on the floor with cameras, and extracting walking trajectories using image processing techniques. To demonstrate its capabilities, the system was installed on a real office floor and resulting trajectories were statistically analyzed to identify the actual walking patterns, paths, pacing rates, and busyness of the floor with respect to time. The correlation between the vibration levels measured by the wireless sensors and the trajectories extracted from the video recordings were also investigated. The results showed that the proposed video-vibration monitoring system has strong potential to be used in training data-driven crowd models, which can be used in future studies to generate realistic multi-person loading scenarios.

Floor vibration is widely recognized as an important limit state in the design of steel-framed floors, and various evaluation methods have been developed over the years. These methods range from simplified methods that are suitable for routine usage during the design phase to complex computerized or probabilistic models. The former are in common usage in the structural design community. It is critically important to structural engineers that the accuracies of the commonly used methods are known; however, a study of these methods based on a large database of recorded observations is not available in the literature. Therefore, the authors investigated the evaluation accuracy of four well-known simplified methods by comparing predicted and observed acceptability (whether or not occupants complained) of 50 floor bays in real buildings framed with W-shaped members subjected to walking excitations. The percentage of correct predictions is used to judge the accuracy of each method. It is observed that the AISC Design Guide 11 accurately predicted acceptability of floors; two methods from the SCI P354 (Simplified Method and Vibration Dose Value Method) fairly accurately predicted acceptability of floors. The HIVOSS method provided unconservative predictions. In addition, modified version of the P354 method was investigated in an attempt to improve the accuracy of these methods.

Steel plate girders with long or unstiffened web panels are often tapered to produce optimized members in buildings and bridges. Web shear strength is a critical limit state for these members because they usually have slender webs. Historically, shear has been apportioned to the web using two methods. The most common method is to assign the entire shear to the web. Alternatively, the Modified Shear Method considers the vertical component of each flange force resulting in web shear force not equal to the total shear. The first objective of this research was to experimentally determine the accuracy of these methods. It was found that the Modified Shear Method accurately predicted the shear resisted by the web at all 18 instrumented cross-sections in ten tested specimens. Several methods for predicting shear strength of unstiffened and long prismatic web panels are available in the literature. The second major objective of this research was to determine if one or more of these methods accurately predicts tapered member shear strength. Measured ultimate shear strengths were compared to predictions. Methods based on Basler's method provided inaccurate predictions. Methods based on Hoglund's method and the method by Lee and colleagues provided accurate predictions.

Background: Glioblastoma (GBM) is a fatal cancer that has eluded major therapeutic advances. Failure to make progress may reflect the absence of a human GBM model that could be used to test compounds for anti-GBM activity. In this respect, the development of brain tumor-initiating cell (BTIC) cultures is a step forward because BTICs appear to capture the molecular diversity of GBM better than traditional glioma cell lines. Here, we perform a comparative genomic and genetic analysis of BTICs and their parent tumors as preliminary evaluation of the BTIC model. Methods: We assessed single nucleotide polymorphisms (SNPs), genome-wide copy number variations (CNVs), gene expression patterns, and molecular subtypes of 11 established BTIC lines and matched parent tumors. Results: Although CNV differences were noted, BTICs retained the major genomic alterations characteristic of GBM. SNP patterns were similar between BTICs and tumors. Importantly, recurring SNP or CNV alterations specific to BTICs were not seen. Comparative gene expression analysis and molecular subtyping revealed differences between BTICs and GBMs. These differences formed the basis of a 63-gene expression signature that distinguished cells from tumors; differentially expressed genes primarily involved metabolic processes. We also derived a set of 73 similarly expressed genes; these genes were not associated with specific biological functions. Conclusions: Although not identical, established BTIC lines preserve the core molecular alterations seen in their parent tumors, as well as the genomic hallmarks of GBM, without acquiring recurring BTIC-specific changes.

Objectives/Hypothesis Determine whether quantitative geometric measures and a computational fluid dynamic (CFD) model derived from medical imaging of children with subglottic stenosis (SGS) can be effective diagnostic and treatment planning tools. Study Design Retrospective chart and imaging review in a tertiary care hospital. Methods Computed tomography scans (n = 17) of children with SGS were analyzed by geometric and CFD methods. Polysomnograms (n = 15) were also analyzed. Radiographic data were age/weight flow normalized and were compared to an atlas created from radiographically normal airways. Five geometric, seven CFD, and five polysomnography measures were analyzed. Statistical analysis utilized a two-sample t test with Bonferroni correction and area under the curve analysis. Results Two geometric indices (the ratio of the subglottic to midtracheal airway, the percent relative reduction of the subglottic airway) and one CFD measure (the percent relative reduction of the hydraulic diameter of the subglottic airway) were significant for determining which children with SGS received surgical intervention. Optimal cutoffs for these values were determined. Polysomnography, the respiratory effort-related arousals index, was significant only prior to Bonferroni correction for determining which children received surgical intervention. Conclusions Geometric and CFD variables were sensitive at determining which patients with SGS received surgical intervention. Discrete quantitative assessment of the pediatric airway was performed, yielding preliminary data regarding possible objective thresholds for surgical versus nonsurgical treatment of disease. This study is limited by its small, retrospective, single-institution nature. Further studies to validate these findings and possibly optimize treatment threshold recommendations are warranted. Level of Evidence 4 Laryngoscope, 2015

With the use of lighter construction materials, more slender architectural designs, and open floor plans resulting in low damping, vibration serviceability has become a dominant design criterion for structural engineers worldwide. In principle, assessment of floor vibration serviceability requires a proper consideration of three key issues: excitation source, system, and receiver. Walking is usually the dominant human excitation for building floors. This paper provides a comprehensive review of a considerable number of references dealing with experimental measurement and mathematical modeling of dynamic forces induced by a single pedestrian. The historical development of walking force modeling - from single harmonic loads to extremely complex stochastic processes - is discussed. As a conclusion to this effort, it is suggested that less reliance should be made by the industry on the deterministic force models, since they have been shown to be overly conservative. Alternatively, due to the random nature of human walking, probabilistic force models seem to be more realistic, while more research is needed to achieve enough confidence to implement in design practice. The financial support for this research was provided by Qatar National Research Fund, QNRF (a member of Qatar Foundation) via the National Priorities Research Program (NPRP), Project No. NPRP8-836-2-353. Scopus

Atlas-building from population data is widely used in medical imaging. However, the emphasis of atlas-building approaches is typically to estimate a spatial alignment to compute a mean / median shape or image based on population data. In this work, we focus on the statistical characterization of the population data, once spatial alignment has been achieved. We introduce and propose the use of the weighted functional boxplot. This allows the generalization of concepts such as the median, percentiles, or outliers to spaces where the data objects are functions, shapes, or images, and allows spatio-temporal atlas-building based on kernel regression. In our experiments, we demonstrate the utility of the approach to construct statistical atlases for pediatric upper airways and corpora callosa revealing their growth patterns. We also define a score system based on the pediatric airway atlas to quantitatively measure the severity of subglottic stenosis (SGS) in the airway. This scoring allows the classification of pre- and post-surgery SGS subjects and radiographically normal controls. Experimental results show the utility of atlas information to assess the effect of airway surgery in children.

Hemorrhoidectomy is considered by many to be a contaminated operation that requires antibiotic prophylaxis to lower the incidence of surgical site infection. In reality, little evidence exists to either support or refute the use of antibiotic prophylaxis in this setting.This study aimed to determine if antibiotic prophylaxis is associated with reduced incidence of postoperative surgical site infection following hemorrhoidectomy.This is a retrospective database review.This study was conducted at multiple institutions.All patients undergoing hemorrhoidectomy with minimum 3-month follow-up were included.The primary outcome measure was the incidence of postoperative surgical site infection.Eight hundred fifty-two patients met the inclusion criteria (50.1% female; mean age, 50.0 ± 13.7 years). The prevalence of preoperative risk factors for surgical site infection included 7.7% with a smoking history, 2.5% with diabetes mellitus, 0.8% receiving steroids, and 0.2% with Crohn's disease. Surgery was performed predominately for 3-column prolapsed internal and mixed internal/external hemorrhoidal disease. All surgeries performed were closed hemorrhoidectomies. Antibiotic prophylaxis was used in a fewer number of cases (41.3% vs 58.7%). Overall, there were only 12 documented postoperative infections identified, producing an overall incidence of 1.4%. Of those patients who developed postoperative surgical site infections, 9 (75%) did not receive antibiotic prophylaxis (p = 0.25). On multivariate regression analysis, no perioperative risk factor was associated with an increased risk of developing a posthemorrhoidectomy surgical site infection. Conversely, there were no adverse antibiotic-related complications such as Clostridium difficile colitis or antibiotic-associated diarrhea in those receiving antibiotic prophylaxis.This study was limited by the retrospective nature of the analysis.Postoperative surgical site infection is an exceedingly rare event following hemorrhoidectomy. Antibiotic prophylaxis does not reduce the incidence of postoperative surgical site infection, and its routine use appears unnecessary.

Field studies were conducted in 2007 and 2008 at Hamilton Farms near Lonoke, Arkansas, USA to evaluate the potential impact of sub-lethal doses of glyphosate and glufosinate on winter wheat ( Tritium aestivum ). Three wheat cultivars were seeded, and glyphosate and glufosinate were applied at 1/10 and 1/20 times the labeled dose at the 3- to 4-leaf, panicle initiation, and boot stages. Both herbicides caused significant injury to wheat; however, wheat response to both herbicides was different. Glufosinate injury occurred rapidly and consisted of mainly leaf necrosis. Glyphosate injury to wheat was minimal and manifested in the form of leaf yellowing. Glyphosate caused shortened flag leaf when applied at PI and reduced canopy height when applied at boot. Injury was minimal to wheat across all treatments, with the highest level of injury being 34% following glufosinate applied at boot. Conversely, wheat was most sensitive to glyphosate at the 3- to 4-leaf stage. Flag leaf length was reduced the greatest by glyphosate at PI, whereas glufosinate reduced flag leaf length minimally. Even though glyphosate injury was lower than that of glufosinate, yield was reduced more by glyphosate. Wheat seed weight and germination were not affected by either herbicide. Wheat appears to be slightly more sensitive to glyphosate with respect to yield; however, it is slightly more sensitive to glufosinate with respect to foliar injury.

Summary Low- (5%) and high-fat (20%) chicken and turkey hotdogs were formulated in three groups: no antimicrobials (control), chemical preservatives (potassium lactate and sodium diacetate) alone and partial replacement of chemical preservatives by green tea (GTE) and grape seed extracts (GSE), surface inoculated (c. 103 CFU g−1) with Listeria monocytogenes, treated with or without heat treatment (65 °C for 104 s) to determine the growth of L. monocytogenes until spoilage (28 days). Maximum growth inhibitions (c. 2.0 CFU g−1) were observed in the treatments having chemical preservatives and plant extracts regardless of the meat and fat type. Furthermore, plant extracts along with chemical preservatives demonstrated additional inhibitory effect on the growth of L. monocytogenes survivors in chicken hotdog samples followed by postpackaging heat treatment. Results demonstrated that natural GTE and GSE can partially replace the chemical preservatives and further enhance the antilisterial activities when combined with heat treatment.

The Virtual Pediatric Airways Workbench (VPAW) is a patient-centered surgical planning software system targeted to pediatric patients with airway obstruction. VPAW provides an intuitive surgical planning interface for clinicians and supports quantitative analysis regarding prospective surgeries to aid clinicians deciding on potential surgical intervention. VPAW enables a full surgical planning pipeline, including importing DICOM images, segmenting the airway, interactive 3D editing of airway geometries to express potential surgical treatment planning options, and creating input files for offline geometric analysis and computational fluid dynamics simulations for evaluation of surgical outcomes. In this paper, we describe the VPAW system and its use in one case study with a clinician to successfully describe an intended surgery outcome.