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Showing papers by "University of Colorado Colorado Springs published in 2015"


Journal ArticleDOI
TL;DR: This paper found small but significant positive effects when black and white students were assigned to race-congruent teachers in reading and for black, white and Asian/Pacific Island students in math.

413 citations


Posted Content
TL;DR: OpenMax as mentioned in this paper adapts Meta-Recognition concepts to the activation patterns in the penultimate layer of the network to estimate the probability of an input being from an unknown class.
Abstract: Deep networks have produced significant gains for various visual recognition problems, leading to high impact academic and commercial applications. Recent work in deep networks highlighted that it is easy to generate images that humans would never classify as a particular object class, yet networks classify such images high confidence as that given class - deep network are easily fooled with images humans do not consider meaningful. The closed set nature of deep networks forces them to choose from one of the known classes leading to such artifacts. Recognition in the real world is open set, i.e. the recognition system should reject unknown/unseen classes at test time. We present a methodology to adapt deep networks for open set recognition, by introducing a new model layer, OpenMax, which estimates the probability of an input being from an unknown class. A key element of estimating the unknown probability is adapting Meta-Recognition concepts to the activation patterns in the penultimate layer of the network. OpenMax allows rejection of "fooling" and unrelated open set images presented to the system; OpenMax greatly reduces the number of obvious errors made by a deep network. We prove that the OpenMax concept provides bounded open space risk, thereby formally providing an open set recognition solution. We evaluate the resulting open set deep networks using pre-trained networks from the Caffe Model-zoo on ImageNet 2012 validation data, and thousands of fooling and open set images. The proposed OpenMax model significantly outperforms open set recognition accuracy of basic deep networks as well as deep networks with thresholding of SoftMax probabilities.

368 citations


Proceedings ArticleDOI
07 Jun 2015
TL;DR: Nearest Non-Outlier (NNO) as mentioned in this paper is an open-world recognition algorithm that evolves model efficiently, adding object categories incrementally while detecting outliers and managing open space risk.
Abstract: With the of advent rich classification models and high computational power visual recognition systems have found many operational applications. Recognition in the real world poses multiple challenges that are not apparent in controlled lab environments. The datasets are dynamic and novel categories must be continuously detected and then added. At prediction time, a trained system has to deal with myriad unseen categories. Operational systems require minimal downtime, even to learn. To handle these operational issues, we present the problem of Open World Recognition and formally define it. We prove that thresholding sums of monotonically decreasing functions of distances in linearly transformed feature space can balance “open space risk” and empirical risk. Our theory extends existing algorithms for open world recognition. We present a protocol for evaluation of open world recognition systems. We present the Nearest Non-Outlier (NNO) algorithm that evolves model efficiently, adding object categories incrementally while detecting outliers and managing open space risk. We perform experiments on the ImageNet dataset with 1.2M+ images to validate the effectiveness of our method on large scale visual recognition tasks. NNO consistently yields superior results on open world recognition.

325 citations


Book ChapterDOI
Abstract: Terror management theory posits that human awareness of the inevitability of death exerts a profound influence on diverse aspects of human thought, emotion, motivation, and behavior. People manage the potential for anxiety that results from this awareness by maintaining: (1) faith in the absolute validity of their cultural worldviews and (2) self-esteem by living up to the standards of value that are part of their worldviews. In this chapter, we take stock of the past 30 years of research and conceptual development inspired by this theory. After a brief review of evidence supporting the theory's fundamental propositions, we discuss extensions of the theory to shed light on: (1) the psychological mechanisms through which thoughts of death affect subsequent thought and behavior; (2) how the anxiety-buffering systems develop over childhood and beyond; (3) how awareness of death influenced the evolution of mind, culture, morality, and religion; (4) how death concerns lead people to distance from their physical bodies and seek solace in concepts of mind and spirit; and (5) the role of death concerns in maladaptive and pathological behavior. We also consider various criticisms of the theory and alternative conceptualizations that have been proposed. We conclude with a discussion of what we view as the most pressing issues for further research and theory development that have been inspired by the theory's first 30 years.

284 citations


Patent
25 Aug 2015
TL;DR: In this article, the authors propose a hybrid lateration and trilateration solution in which the mobile device performs location determination calculations with the aid of network components or global positioning systems (GPS).
Abstract: Methods, devices and systems for generating enhanced location information on or about a mobile device may include hybrid lateration and trilateration solutions in which the mobile device performs location determination calculations with the aid of network components or global positioning systems (GPS). Mobile devices may automatically form groups based on proximity and/or may be grouped together via a network server. Mobile devices in a group may share computed location information and/or information collected from internal sensors with other grouped mobile devices. Information shared between grouped mobile devices may be used to enhance the location information computed on each mobile device. For example, each mobile device may supplement and/or augment previously computed location information based on the received location information and/or relative positions of other mobile devices in the same group. Each mobile device may also utilize local sensors to further enhance their location information.

219 citations


Journal ArticleDOI
TL;DR: Empirically evaluate several major information metrics, namely, Hartley entropy, Shannon entropy, Renyi’s entropy, generalized entropy, Kullback–Leibler divergence and generalized information distance measure in their ability to detect both low-rate and high-rate DDoS attacks.

182 citations


Journal ArticleDOI
13 Oct 2015-PLOS ONE
TL;DR: A novel dynamic transition model is developed that informs clinical trial design for prostate cancer by quantifying outcomes in PCCS, and demonstrates the impact of an effective therapy applied in an earlier clinical state of nmCRPC on the incidence of mCRPC morbidity and subsequent mortality.
Abstract: Objective To identify patient populations most in need of treatment across the prostate cancer disease continuum, we developed a novel dynamic transition model based on risk of disease progression and mortality. Design and Outcome Measurements We modeled the flow of patient populations through eight prostate cancer clinical states (PCCS) that are characterized by the status of the primary tumor, presence of metastases, prior and current treatment, and testosterone levels. Simulations used published US incidence rates for each year from 1990. Progression and mortality rates were derived from published clinical trials, meta-analyses, and observational studies. Model outputs included the incidence, prevalence, and mortality for each PCCS. The impact of novel treatments was modeled in three distinct scenarios: metastatic castration-resistant prostate cancer (mCRPC), non-metastatic CRPC (nmCRPC), or both. Results and Limitations The model estimated the prevalence of prostate cancer as 2,219,280 in the US in 2009 and 3,072,480 in 2020, and incidence of mCRPC as 36,100 and 42,970, respectively. All-cause mortality in prostate cancer was estimated at 168,290 in 2009 and 219,360 in 2020, with 20.5% and 19.5% of these deaths, respectively, occurring in men with mCRPC. The majority (86%) of incidence flow into mCRPC states was from the nmCRPC clinical state. In the scenario with novel interventions for nmCRPC states, the progression to mCRPC is reduced, thus decreasing mCRPC incidence by 12% in 2020, with a sustained decline in mCRPC mortality. A limitation of the model is that it does not estimate prostate cancer—specific mortality. Conclusion The model informs clinical trial design for prostate cancer by quantifying outcomes in PCCS, and demonstrates the impact of an effective therapy applied in an earlier clinical state of nmCRPC on the incidence of mCRPC morbidity and subsequent mortality.

172 citations


Journal ArticleDOI
TL;DR: The EXCITE ISR trial is the first large, prospective, randomized study to demonstrate superiority of ELA + PTA versus PTA alone for treating femoropopliteal ISR, with significantly fewer procedural complications.
Abstract: Objectives: The purpose of this study was to evaluate the safety and efficacy of excimer laser atherectomy (ELA) with adjunctive percutaneous transluminal angioplasty (PTA) versus PTA alone...

168 citations


Journal Article
TL;DR: The integration of 21st-century skills in the curriculum is not only beneficial to students and teachers, but also necessary to prepare our youth for their future careers as mentioned in this paper, as the future of our students depends on flexibility and resourcefulness not teaching to the test.
Abstract: The integration of Common Core State Standards (CCSS) and 21st century skills in the curriculum is not only beneficial to students and teachers, but also necessary to prepare our youth for their future careers. In an age of education where standardized tests determine the success of our schools, it is important to allow students the creativity and use the power of technology to support necessary skills and learn in unique ways. By allowing creative thinking and gauging understanding of content standards through a portfolio based system, students can display their concept retention while producing tangible and valuable outcomes. The future of our students depends on flexibility and resourcefulness not teaching to the test. Education needs to make an instructional shift in order to ensure our students succeed as the innovators of the future. This article explores 21st century skills, as they are defined and describes methods that allow students to enhance these skills. It also highlights how educators can link students’ current knowledge with authentic experiences that motivate, as well as allow them to create and collaborate using the latest technologies. The article concludes with a discussion around benefits of integrating multimedia in the classroom, including giving students the opportunity to enhance academic and social skills as they communicate and share information, organize their ideas, and express opinions while preparing a project or conducting research through online experience. Keywords: CCSS, 21st century skills, Integrating 21st century skills to the Curriculum, Methods of instruction 21st Century

155 citations


Journal ArticleDOI
TL;DR: Secondary patient outcomes are presented, including disease-free survival, a specified endpoint by protocol, and data for distant recurrence-free interval, and overall survival, which were not prespecified endpoints but were collected prospectively.
Abstract: Summary Background NSABP B-40 was a 3 × 2 factorial trial testing whether adding capecitabine or gemcitabine to docetaxel followed by doxorubicin plus cyclophosphamide neoadjuvant chemotherapy would improve outcomes in women with operable, HER2-negative breast cancer and whether adding neoadjuvant plus adjuvant bevacizumab to neoadjuvant chemotherapy regimens would also improve outcomes. As reported previously, addition of neoadjuvant bevacizumab increased the proportion of patients achieving a pathological complete response, which was the primary endpoint. We present secondary patient outcomes, including disease-free survival, a specified endpoint by protocol, and data for distant recurrence-free interval, and overall survival, which were not prespecified endpoints but were collected prospectively. Methods In this randomised controlled trial (NSABP B-40), we enrolled women aged 18 years or older, with operable, HER2-non-amplified invasive adenocarcinoma of the breast, 2 cm or greater in diameter by palpation, clinical stage T1c–3, cN0, cN1, or cN2a, without metastatic disease and diagnosed by core needle biopsy. Patients received one of three docetaxel-based neoadjuvant regimens for four cycles: docetaxel alone (100 mg/m 2 ) with addition of capecitabine (825 mg/m 2 oral twice daily days 1–14, 75 mg/m 2 docetaxel) or with addition of gemcitabine (1000 mg/m 2 days 1 and 8 intravenously, 75 mg/m 2 docetaxel), all followed by neoadjuvant doxorubicin and cyclophosphamide (60 mg/m 2 and 600 mg/m 2 intravenously) every 3 weeks for four cycles. Those randomly assigned to bevacizumab groups were to receive bevacizumab (15 mg/kg, every 3 weeks for six cycles) with neoadjuvant chemotherapy and postoperatively for ten doses. Randomisation was done (1:1:1:1:1:1) via a biased-coin minimisation procedure to balance the characteristics with respect to clinical nodal status, clinical tumour size, hormone receptor status, and age. Intent-to-treat analyses were done for disease-free survival and overall survival. This study is registered with ClinicalTrials.gov, number NCT00408408. Findings Between Jan 5, 2007, and June 30, 2010, 1206 patients were enrolled in the study. Follow-up data were collected from Oct 31, 2007 to March 27, 2014, and were available for overall survival in 1186 patients, disease-free survival in 1184, and distant recurrence-free interval in 1181. Neither capecitabine nor gemcitabine increased disease-free survival or overall survival. Median follow-up was 4·7 years (IQR 4·0–5·2). The addition of bevacizumab significantly increased overall survival (hazard ratio 0·65 [95% CI 0·49–0·88]; p=0·004) but did not significantly increase disease-free survival (0·80 [0·63–1·01]; p=0·06). Four deaths occurred on treatment due to vascular disorder (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), sudden death (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), infective endocarditis (docetaxel plus bevacizumab followed by doxorubicin plus cyclophosphamide and bevacizumab group), and visceral arterial ischaemia (docetaxel followed by doxorubicin plus cyclophosphamide group). The most common grade 3–4 adverse events in the bevacizumab group were neutropenia (grade 3, 99 [17%]; grade 4, 37 [6%]), hand-foot syndrome (grade 3, 63 [11%]), and hypertension (grade 3, 60 [10%]; grade 4, two [ Interpretation The addition of gemcitabine or capecitabine to neoadjuvant docetaxel plus doxorubicin plus cyclophosphamide does not seem to provide any benefit to patients with operable breast cancer, and should not change clinical practice in the short term. The improved overall survival with bevacizumab contradicts the findings of other studies of bevacizumab in breast cancer and may indicate the need for additional investigation of this agent. Funding National Institutes of Health, Genentech, Roche Laboratories, Lilly Research Laboratories, and Precision Therapeutics.

136 citations


Journal ArticleDOI
TL;DR: A research model shows how transformational leadership, safety climate, and continuous quality improvement (CQI) initiatives are related to objective quality and patient safety outcome measures, and confirms the importance of using CQI to effectively enhance process quality in hospitals, and patient health climate to improve patient safety outcomes.
Abstract: Background Successful amelioration of medical errors represents a significant problem in the health care industry. There is a need for greater understanding of the factors that lead to improved process quality and patient safety outcomes in hospitals. Purpose We present a research model that shows how transformational leadership, safety climate, and continuous quality improvement (CQI) initiatives are related to objective quality and patient safety outcome measures. Methodology/approach The proposed framework is tested using structural equation modeling, based on data collected for 204 hospitals, and supplemented with objective outcome data from the Centers for Medicare and Medicaid Services. Findings The results provide empirical evidence that a safety climate, which is connected to the chief executive officer's transformational leadership style, is related to CQI initiatives, which are linked to improved process quality. A unique finding of this study is that, although CQI initiatives are positively associated with improved process quality, they are also associated with higher hospital-acquired condition rates, a measure of patient safety. Likewise, safety climate is directly related to improved patient safety outcomes. Practical implications The notion that patient safety climate and CQI initiatives are not interchangeable or universally beneficial is an important contribution to the literature. The results confirm the importance of using CQI to effectively enhance process quality in hospitals, and patient safety climate to improve patient safety outcomes. The overall pattern of findings suggests that simultaneous implementation of CQI initiatives and patient safety climate produces greater combined benefits.

Journal ArticleDOI
02 Nov 2015
TL;DR: In this article, the effects of nanoscale dopants on the electrical properties of liquid crystals were investigated and the most promising inorganic and organic nanomaterials suitable to capture ions in liquid crystals was identified.
Abstract: The presence of ions in liquid crystals is one of the grand challenges that hinder the application of liquid crystals in various devices, which include advanced 3-D and flexible displays, tunable lenses, etc. Not only do they compromise the overall performance of liquid crystal devices, ions are also responsible for slow response, image sticking, and image flickering, as well as many other negative effects. Even highly purified liquid crystal materials can get contaminated during the manufacturing process. Moreover, liquid crystals can degrade over time and generate ions. All of these factors raise the bar for their quality control, and increase the manufacturing cost of liquid crystal products. A decade of dedicated research has paved the way to the solution of the issues mentioned above through merging liquid crystals and nanotechnology. Nano-objects (guests) that are embedded in the liquid crystals (hosts) can trap ions, which decreases the ion concentration and electrical conductivity, and improves the electro-optical response of the host. In this paper, we (i) review recently published works reporting the effects of nanoscale dopants on the electrical properties of liquid crystals; and (ii) identify the most promising inorganic and organic nanomaterials suitable to capture ions in liquid crystals.

Journal ArticleDOI
TL;DR: To rationalize the different optical properties observed, density functional theory calculations were performed for the three clusters giving straightforward explanation for the different luminescence thermochromism observed, which is attributed to different contributions of the ligands to the molecular orbitals.
Abstract: An original copper(I) iodide cluster of novel geometry obtained by using a diphosphine ligand is reported and is formulated [Cu6I6(PPh2(CH2)3PPh2)3] (1). Interestingly, this sort of “eared cubane” cluster based on the [Cu6I6] inorganic core can be viewed as a combination of the two known [Cu4I4] units, namely, the cubane and the open-chair isomeric geometries. The synthesis, structural and photophysical characterisations, as well as theoretical study of this copper iodide along with the derived cubane (3) and open-chair (2) [Cu4I4(PPh3)4] forms, were investigated. A new polymorph of the cubane [Cu4I4(PPh3)4] cluster is indeed presented (3). The structural differences of the clusters were analyzed by solid-state nuclear magnetic resonance spectroscopy. Luminescence properties of the three clusters were studied in detail as a function of the temperature showing reversible luminescence thermochromism for 1 with an intense orange emission at room temperature. This behavior presents different feature compared to the cubane cluster and completely contrasts with the open isomer, which is almost nonemissive at room temperature. Indeed, the thermochromism of 1 differs by a concomitant increase of the two emission bands by lowering the temperature, in contrast to an equilibrium phenomenon for 3. The luminescence properties of 2 are very different by exhibiting only one single band when cooled. To rationalize the different optical properties observed, density functional theory calculations were performed for the three clusters giving straightforward explanation for the different luminescence thermochromism observed, which is attributed to different contributions of the ligands to the molecular orbitals. Comparison of 3 with its [Cu4I4(PPh3)4] cubane polymorphs highlights the sensibility of the emission properties to the cuprophilic interactions.

Journal ArticleDOI
TL;DR: The use of the proposed list of 53 good practice characteristics may foster further development of health promotion sciences, as it would allow for identification of success vectors in the domains of main characteristics of interventions/policies, their implementation, evaluation and monitoring processes.
Abstract: This umbrella review aimed at eliciting good practice characteristics of interventions and policies aiming at healthy diet, increasing physical activity, and lowering sedentary behaviors. Applying the World Health Organization’s framework, we sought for 3 types of characteristics, reflecting: (1) main intervention/policy characteristics, referring to the design, targets, and participants, (2) monitoring and evaluation processes, and (3) implementation issues. This investigation was undertaken by the DEDPIAC Knowledge Hub (the Knowledge Hub on the DEterminants of DIet and Physical ACtivity), which is an action of the European Union’s joint programming initiative.

Journal ArticleDOI
TL;DR: The robustness and accuracy of the localization approach on a challenging dataset is shown, and the unconstrained global SLAM mapping and tracking of arbitrary camera motion on several sequences are demonstrated.
Abstract: We present a method for large-scale geo-localization and global tracking of mobile devices in urban outdoor environments. In contrast to existing methods, we instantaneously initialize and globally register a SLAM map by localizing the first keyframe with respect to widely available untextured 2.5D maps. Given a single image frame and a coarse sensor pose prior, our localization method estimates the absolute camera orientation from straight line segments and the translation by aligning the city map model with a semantic segmentation of the image. We use the resulting 6DOF pose, together with information inferred from the city map model, to reliably initialize and extend a 3D SLAM map in a global coordinate system, applying a model-supported SLAM mapping approach. We show the robustness and accuracy of our localization approach on a challenging dataset, and demonstrate unconstrained global SLAM mapping and tracking of arbitrary camera motion on several sequences.

Journal ArticleDOI
TL;DR: A large series of tests revealed that the method provides structure models with an average error in atomic positions typically between 0.01 and 0.02 Å, which is significantly more accurate than models obtained by refinement using kinematical approximation for the calculation of model intensities.
Abstract: The recently published method for the structure refinement from three-dimensional precession electron diffraction data using dynamical diffraction theory [Palatinus et al. (2015). Acta Cryst. A71, 235-244] has been applied to a set of experimental data sets from five different samples - Ni2Si, PrVO3, kaolinite, orthopyroxene and mayenite. The data were measured on different instruments and with variable precession angles. For each sample a reliable reference structure was available. A large series of tests revealed that the method provides structure models with an average error in atomic positions typically between 0.01 and 0.02 A. The obtained structure models are significantly more accurate than models obtained by refinement using kinematical approximation for the calculation of model intensities. The method also allows a reliable determination of site occupancies and determination of absolute structure. Based on the extensive tests, an optimal set of the parameters for the method is proposed.

Journal ArticleDOI
25 Aug 2015-PLOS ONE
TL;DR: Results contribute to a discussion on the origins of STS and job burnout among human services personnel working in highly demanding context of work-related secondary exposure to traumatic events and confirm that job burnouts contributes to the development of STs.
Abstract: This longitudinal research examined the directions of the relationships between job burnout and secondary traumatic stress (STS) among human services workers. In particular, using cross-lagged panel design, we investigated whether job burnout predicts STS at 6-month follow up or whether the level of STS symptoms explains job burnout at 6-month follow-up. Participants in Study 1 were behavioral or mental healthcare providers (N = 135) working with U.S. military personnel suffering from trauma. Participants in Study 2 were healthcare providers, social workers, and other human services professions (N = 194) providing various types of services for civilian trauma survivors in Poland. The cross-lagged analyses showed consistent results for both longitudinal studies; job burnout measured at Time 1 led to STS at Time 2, but STS assessed at Time 1 did not lead to job burnout at Time 2. These results contribute to a discussion on the origins of STS and job burnout among human services personnel working in highly demanding context of work-related secondary exposure to traumatic events and confirm that job burnout contributes to the development of STS.

Journal ArticleDOI
TL;DR: In this paper, the crystal structure of NASICON Na3V2(PO4)3 phase (NVP) has been investigated as a function of temperature and the presence of four polymorphs of NVP from 30 to 225 °C.
Abstract: The crystal structure of the NASICON Na3V2(PO4)3 phase (NVP) has been investigated as a function of temperature. Combining laboratory and synchrotron X-ray powder diffraction with single crystal X-ray diffraction, we demonstrate the presence of four polymorphs of NVP from 30 to 225 °C. While the high temperature γ-NVP crystallizes in the classical rhombohedral cell (S.G. R3c, a = 8.73382(4) A, c = 21.91438(17) A), the low temperature α-NVP undergoes a monoclinic distortion (S.G. C2/c, a = 15.1244(6) A, b = 8.7287(3) A, c = 21.6143(8) A, β = 90.163(2)°) together with an ordering of the Na atoms. In the middle temperature range, two incommensurate modulated structures (β- and β′-NVP) are also reported for the first time.

Journal ArticleDOI
TL;DR: Examination of associations between suicidal ideation and plausible risk factors (experience of abuse in childhood or as an adult, sleep disturbance, and anxiety symptoms) in depressed postpartum women found that having frequent thoughts of self-harm was related to childhood physical abuse.

Journal ArticleDOI
TL;DR: In this article, the present value of electrochemical internal variables in a lithium-ion cell was estimated using readily available measurements of cell voltage, current, and temperature, using an extended Kalman filter along with a one-dimensional physics-based reduced-order model of cell dynamics.

BookDOI
26 Mar 2015
TL;DR: In this paper, the authors derive conservation laws for solutions of wave equations and derive Strichartz estimates to deal with semi-linear problems with data (f, g) ∈ Hs × Hs−1 for large enough s.
Abstract: where := −∂2 t +∆ and u[0] := (u, ut)|t=0. The equation is semi-linear if F is a function only of u, (i.e. F = F (u)), and quasi-linear if F is also a function of the derivatives of u (i.e. F = F (u,Du), where D := (∂t,∇)). The goal is to use energy methods to prove local well-posedness for quasilinear equations with data (f, g) ∈ Hs × Hs−1 for large enough s, and then to derive Strichartz estimates to deal with semi-linear problems with data (f, g) ∈ Ḣ1 × L2. We begin, however, by deriving various conservation laws for solutions of wave equations.

Journal ArticleDOI
TL;DR: In this paper, a significant improvement of modulation bandwidth from 2 × 1$ photonic crystal vertical-cavity surface-emitting laser arrays was achieved by control of injection bias conditions to array elements.
Abstract: We show a significant improvement of modulation bandwidth from $2\times 1$ photonic crystal vertical-cavity surface-emitting laser arrays. Control of injection bias conditions to array elements enables resonance tuning of each element with variation of the phase relation and coherence of the array, resulting in the ability to tailor the modulation response. A bandwidth of 37 GHz is obtained under highly single-mode coherent operation with narrow spectral width and increased output power while the laser array is biased at low current density. Lasers with such performance characteristics may greatly enhance high-rate data transfer in computer server, data center, and supercomputer applications with potentially long device lifetime.

Journal ArticleDOI
TL;DR: It is suggested that RelBbu globally modulates transcription in response to nutrient stress by increasing (p)ppGpp levels to facilitate B. burgdorferi persistence in the tick.
Abstract: As the Lyme disease bacterium Borrelia burgdorferi traverses its enzootic cycle, alternating between a tick vector and a vertebrate host, the spirochete must adapt and persist in the tick midgut under prolonged nutrient stress between blood meals. In this study, we examined the role of the stringent response in tick persistence and in regulation of gene expression during nutrient limitation. Nutritionally starving B. burgdorferi in vitro increased the levels of guanosine tetraphosphate (ppGpp) and guanosine pentaphosphate (pppGpp), collectively referred to as (p)ppGpp, products of the bifunctional synthetase/hydrolase RelBbu (RelA/SpoT homolog). Conversely, returning B. burgdorferi to a nutrient-rich medium decreased (p)ppGpp levels. B. burgdorferi survival in ticks between the larval and nymph blood meals, and during starvation in vitro, was dependent on RelBbu. Furthermore, normal morphological conversion from a flat-wave shape to a condensed round body (RB) form during starvation was dependent on RelBbu; relBbu mutants more frequently formed RBs, but their membranes were compromised. By differential RNA sequencing analyses, we found that RelBbu regulates an extensive transcriptome, both dependent and independent of nutrient stress. The RelBbu regulon includes the glp operon, which is important for glycerol utilization and persistence in the tick, virulence factors and the late phage operon of the 32-kb circular plasmid (cp32) family. In summary, our data suggest that RelBbu globally modulates transcription in response to nutrient stress by increasing (p)ppGpp levels to facilitate B. burgdorferi persistence in the tick.

Journal ArticleDOI
TL;DR: The use of an agreed-upon hashtag and the number of users following an official account positively influence message retransmission, as does message content describing hazard impacts or emphasizing cohesion among users, which suggests some measures commonly taken to convey additional information to the public may come at a cost in terms of message amplification.
Abstract: For decades, public warning messages have been relayed via broadcast information channels, including radio and television; more recently, risk communication channels have expanded to include social media sites, where messages can be easily amplified by user retransmission. This research examines the factors that predict the extent of retransmission for official hazard communications disseminated via Twitter. Using data from events involving five different hazards, we identity three types of attributes--local network properties, message content, and message style--that jointly amplify and/or attenuate the retransmission of official communications under imminent threat. We find that the use of an agreed-upon hashtag and the number of users following an official account positively influence message retransmission, as does message content describing hazard impacts or emphasizing cohesion among users. By contrast, messages directed at individuals, expressing gratitude, or including a URL were less widely disseminated than similar messages without these features. Our findings suggest that some measures commonly taken to convey additional information to the public (e.g., URL inclusion) may come at a cost in terms of message amplification; on the other hand, some types of content not traditionally emphasized in guidance on hazard communication may enhance retransmission rates.

Journal ArticleDOI
TL;DR: Low EI, and specifically low carbohydrate intake, appears to be the main contributor to chronic LEA in adult male and female competitive road and off-road cyclists in the United States who may be at risk for long-term LEA.
Abstract: The purpose of this study was to assess energy availability (EA) and dietary patterns of 10 adult (29-49 years) male (n = 6) and female (n = 4) competitive (USA Cycling Category: Pro, n = 2; 1-4, n = 8) endurance cyclists (5 road, 5 off-road), with lower than expected bone mineral density (BMD; Z score < 0) across a season. Energy intake (EI) and exercise energy expenditure during preseason (PS), competition (C), and off-season (OS) were estimated from 3-day dietary records, completed once per month, across a cycling season. BMD was measured by DXA at 0 months/5 months/10 months. The Three-Factor Eating Questionnaire (TFEQ) was used to assess cognitive dietary restraint. Seventy percent of participants had low EA [(LEA); < 30 kcal · kg fat-free mass (FFM) (-1) · day(-1)] during PS, 90% during C, and 80% during OS (range: 3-37 kcal · kg FFM(-1) · day(-1)). Ninety percent of cyclists had LEA during ≥ 1 training period, and 70% had LEA across the season. Seventy percent of cyclists were identified as restrained eaters who consciously restrict EI as a means of weight control. Mean daily carbohydrate intake was below sport nutrition recommendations during each training period (PS: 3.9 ± 1.1 g · kg(-1) · day(-1), p < .001; C: 4.3 ± 1.4 g · kg(-1) · day(-1), p = .005; OS: 3.7 ± 1.4 g · kg(-1) · day(-1), p = .01). There were no differences in EA and EI · kg(-1) between male and female cyclists and road and off-road cyclists. Low EI, and specifically low carbohydrate intake, appears to be the main contributor to chronic LEA in these cyclists. Adult male and female competitive road and off-road cyclists in the United States may be at risk for long-term LEA. Further studies are needed to explore strategies to prevent and monitor long-term LEA in these athletes.

Journal ArticleDOI
04 Mar 2015-ACS Nano
TL;DR: Comparative 2D Fourier analysis of physical height and photocurrent images shows high spatial frequency spatial variations in substrate/MoS2 contact that exceed the frequencies imposed by the underlying substrates.
Abstract: Atomically thin MoS2 is of great interest for electronic and optoelectronic applications because of its unique two-dimensional (2D) quantum confinement; however, the scaling of optoelectronic properties of MoS2 and its junctions with metals as a function of layer number as well the spatial variation of these properties remain unaddressed. In this work, we use photocurrent spectral atomic force microscopy (PCS-AFM) to image the current (in the dark) and photocurrent (under illumination) generated between a biased PtIr tip and MoS2 nanosheets with thickness ranging between n = 1 to 20 layers. Dark current measurements in both forward and reverse bias reveal characteristic diode behavior well-described by Fowler–Nordheim tunneling with a monolayer barrier energy of 0.61 eV and an effective barrier scaling linearly with layer number. Under illumination at 600 nm, the photocurrent response shows a marked decrease for layers up to n = 4 but increasing thereafter, which we describe using a model that accounts fo...

Journal ArticleDOI
21 Aug 2015-PLOS ONE
TL;DR: This study provides the first examination of terse message retransmission of official warning messages in response to a domestic terrorist attack, the Boston Marathon Bombing in 2013, using messages posted from public officials’ Twitter accounts and employs a negative binomial model to examine how message characteristics affect messageretransmission.
Abstract: Message retransmission is a central aspect of information diffusion. In a disaster context, the passing on of official warning messages by members of the public also serves as a behavioral indicator of message salience, suggesting that particular messages are (or are not) perceived by the public to be both noteworthy and valuable enough to share with others. This study provides the first examination of terse message retransmission of official warning messages in response to a domestic terrorist attack, the Boston Marathon Bombing in 2013. Using messages posted from public officials’ Twitter accounts that were active during the period of the Boston Marathon bombing and manhunt, we examine the features of messages that are associated with their retransmission. We focus on message content, style, and structure, as well as the networked relationships of message senders to answer the question: what characteristics of a terse message sent under conditions of imminent threat predict its retransmission among members of the public? We employ a negative binomial model to examine how message characteristics affect message retransmission. We find that, rather than any single effect dominating the process, retransmission of official Tweets during the Boston bombing response was jointly influenced by various message content, style, and sender characteristics. These findings suggest the need for more work that investigates impact of multiple factors on the allocation of attention and on message retransmission during hazard events.

Journal ArticleDOI
01 Jan 2015
TL;DR: In this paper, in situ measurements by mid-IR laser absorption spectroscopy of C 2H 4 /Ar dissociation and C 2 H 4 /O 2 /Ar oxidation activated by a nanosecond repetitively pulsed plasma have been conducted in a low temperature flow reactor (below 500 K) at a pressure of 60 Torr for both a continuously pulsed discharge mode and a burst mode with 150 pulses.
Abstract: In situ measurements by mid-IR laser absorption spectroscopy of C 2 H 4 /Ar dissociation and C 2 H 4 /O 2 /Ar oxidation activated by a nanosecond repetitively pulsed plasma have been conducted in a low temperature flow reactor (below 500 K) at a pressure of 60 Torr for both a continuously pulsed plasma discharge mode and a burst mode with 150 pulses. The measurements of the in situ diagnostics are validated and complemented by gas chromatography in the continuous discharge mode. A recently developed kinetic mechanism (HP-Mech-Plasma) for plasma activated C 2 H 4 oxidation is assembled. The experiments of plasma activated dissociation show that the formation of acetylene by direct electron impact dissociation and dissociation by excited and ionized argon collision reactions is the major fuel consumption pathway. Plasma activated C 2 H 4 oxidation experiments show that there exist three fuel consumption pathways, (1) a plasma activated low temperature fuel oxidation pathway via O 2 addition reactions; (2) a direct fragmentation pathway via collisional dissociation by electrons, ions, and electronically excited molecules; and (3) a direct oxidation pathway by plasma generated radicals. It is found that the plasma activated low temperature oxidation pathway is dominant and leads to a large amount of formaldehyde formation with less acetylene and negligible large hydrocarbon molecules as compared to the dissociation experiment. The results also indicate that the latter two fuel consumption pathways are strongly dependent on O 2 and Ar concentrations due to their effect on the production of atomic oxygen and excited Ar. Although the current model improves the overall prediction over USC-Mech II for plasma activated dissociation and oxidation, both models fail to predict quantitatively the H 2 O and CH 4 formation. The present data provide good targets for future model development in plasma-assisted combustion.

Journal ArticleDOI
TL;DR: The use of the proposed list of 83 conditions for successful implementation may enhance the implementation of interventions and policies which pursue identification of the most successful actions aimed at improving diet, PA and reducing SB.
Abstract: Background: This umbrella review aimed at identifying evidence-based conditions important for successful implementation of interventions and policies promoting a healthy diet, physical activity (PA), and a reduction in sedentary behaviors (SB). In particular, we examined if the implementation conditions identified were interventionspecific or policy-specific. This study was undertaken as part of the DEterminants of DIet and Physical Activity (DEDIPAC) Knowledge Hub, a joint action as part of the European Joint Programming Initiative a Healthy Diet for a Healthy Life. Methods: A systematic review of reviews and stakeholder documents was conducted. Data from nine scientific literature databases were analyzed (95 documents met the inclusion criteria). Additionally, published documentation of eight major stakeholders (e.g., World Health Organization) were systematically searched (17 documents met the inclusion criteria). The RE-AIM framework was used to categorize elicited conditions. Across the implementation conditions 25 % were identified in at least four documents and were subsequently classified as having obtained sufficient support. Results: We identified 312 potential conditions relevant for successful implementation; 83 of these received sufficient support. Using the RE-AIM framework eight implementation conditions that obtained support referred to the reach in the target population; five addressed efficacy of implementation processes; 24 concerned adoption by the target staff, setting, or institutions; 43 referred to consistency, costs, and adaptations made in the implementation process; three addressed maintenance of effects over time. The vast majority of implementation conditions (87.9 %; 73 of 83) were supported by documents referring to both interventions and policies. There were seven policy-specific implementation conditions, which focused on increasing complexities of coexisting policies/legal instruments and their consequences for implementation, as well as politicians’ collaboration in implementation. Conclusions: The use of the proposed list of 83 conditions for successful implementation may enhance the implementation of interventions and policies which pursue identification of the most successful actions aimed at improving diet, PA and reducing SB.

Journal ArticleDOI
TL;DR: In this paper, the authors exploit the strong dependence of gap-plasmon phase velocity on gap width to make a compact phase-modulator with moderate losses and an electromechanically variable gap size.
Abstract: Researchers exploit the strong dependence of gap-plasmon phase velocity on gap width to make a compact phase-modulator. An electromechanically variable gap size enables a 23-μm-long non-resonant modulator with moderate losses.