1,365 research outputs found
An Instrument Employing a Coronal Discharge for the Determination of Droplet-Size Distribution in Clouds
A flight instrument that uses electric means for measuring the droplet-size distribution in above-freezing clouds has been devised and given preliminary evaluation in flight. An electric charge is placed on the droplets and they are separated aerodynamically according to their mass. Because the charge placed on the droplets is a. function of the droplet size, the size spectrum can 'be determined by measurement of the charge deposited on cylinders of several different sizes placed to intercept the charged droplets. An expression for the rate of charge acquisition by a water droplet in a field of coronal discharge is derived. The results obtained in flight with an instrument based on the method described indicate that continuous records of droplet-size spectrum variations in clouds can be obtained. The experimental instrument was used to evaluate the method and was not refined to the extent necessary for obtaining conclusive meteorological data. The desirable features of an instrument based on the method described are (i) The instrument can be used in clouds with temperatures above freezing; (2) the size and the shape of the cylinders do not change during the exposure time; (3) the readings are instantaneous and continuous; (4) the available sensitivity permits the study of variations in cloud structures of less than 200 feet in extent
Identifying and Indexing Icosahedral Quasicrystals from Powder Diffraction Patterns
We present a scheme to identify quasicrystals based on powder diffraction
data and to provide a standardized indexing. We apply our scheme to a large
catalog of powder diffraction patterns, including natural minerals, to look for
new quasicrystals. Based on our tests, we have found promising candidates
worthy of further exploration.Comment: 4 pages, 1 figur
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When and why people misestimate future feelings: Identifying strengths and weaknesses in affective forecasting.
People try to make decisions that will improve their lives and make them happy, and to do so, they rely on affective forecasts-predictions about how future outcomes will make them feel. Decades of research suggest that people are poor at predicting how they will feel and that they commonly overestimate the impact that future events will have on their emotions. Recent work reveals considerable variability in forecasting accuracy. This investigation tested a model of affective forecasting that captures this variability in bias by differentiating emotional intensity, emotional frequency, and mood. Two field studies examined affective forecasting in college students receiving grades on a midterm exam (Study 1, N = 643), and U.S. citizens after the outcome of the 2016 presidential election (Study 2, N = 706). Consistent with the proposed model, participants were more accurate in forecasting the intensity of their emotion and less accurate in forecasting emotion frequency and mood. Overestimation of the effect of the event on mood increased over time since the event. Three experimental studies examined mechanisms that contribute to differential forecasting accuracy. Biases in forecasting intensity were caused by changes in perceived event importance; biases in forecasting frequency of emotion were caused by changes in the frequency of thinking about the event. This is the first direct evidence mapping out strengths and weaknesses for different types of affective forecasts and the factors that contribute to this pattern. (PsycINFO Database Record (c) 2019 APA, all rights reserved)
Teaching Expatriate Adaptation While Dealing With Reality: The Impact of a Tragedy on the Study-Abroad Experience
This paper explores the relevance of the accepted U-shaped models of expatriate adaptation to students engaged in an international educational experience when they are faced with a tragedy. In this study-abroad course, an examination of the existing adaptation models and how they provide a set of expectations for the process of cultural adjustment is presented as course material. During a particular four-week summer program, one of the nineteen students who went abroad died in an accident at the end of the first week. It became clear after the tragedy that the models studied failed to explain the impact of a personal tragedy of this magnitude on the studentsβ adjustment process. This unfortunate event provided an opportunity to conduct a quasi-experiment to consider the impact of personal tragedy for students to question a body of research through their own personal experience and for scholars to re-examine and update the existing models
Naturalistic observation for understanding users: How technology professionals use and communicate information
This study examines how design engineers and technical professionals (hereafter referred to as engineers) in innovative highβtech firms in the U.S. and India communicate and use information in their daily work activities including research, development, and management. By observing engineers in the workplace, it extends our understanding of the engineering workplace, and the information environment in the workplace. This study will provide information useful for improving communication and information methods for accessing information and communicating in the workplace, which will ultimately lead to better job performance, facilitate innovation, and encourage economic growth. This poster focuses on the methodology the researchers used to gather data for the study. Researchers conducted a series of daylong workplace observations with 108 engineers engaged in product design and testing in four U.S. and two India based firms. Using naturalistic observation provided researchers with the ability to see engineers in their workplace carrying out their daily work rather than depending on selfβreported data which may be incomplete. The poster focuses on the naturalistic observation method, how it was employed, and lessons learned in conducting the work in the U.S. and India
Summer Study-Abroad Program as Experiential Learning: Examining Similarities and Differences in International Communication
This paper examines how the study-abroad experience enhances intercultural communication competence. This study used Bennettβs (1986, 1993) model of ethnorelative typology of acceptance, adaptation, and integration to explore intercultural communication competency. Central to intercultural communication competency is intercultural sensitivity and modified perceptions of cultural differences. A pre-test/post-test open-ended questionnaire design was utilized to uncover what was learned by students while participating in a four-week summer study-abroad program in Paris and Brussels. Based on 110 participants over 16 years, results indicated that both sensitivity to and understanding of cultural differences are heightened as a result of the study-abroad experience. Further, these findings provided support for outcomes showing attainment of intercultural communication competency learning objectives
Computational Modeling of the Crosstalk Between Macrophage Polarization and Tumor Cell Plasticity in the Tumor Microenvironment
Tumor microenvironments contain multiple cell types interacting among one another via different signaling pathways. Furthermore, both cancer cells and different immune cells can display phenotypic plasticity in response to these communicating signals, thereby leading to complex spatiotemporal patterns that can impact therapeutic response. Here, we investigate the crosstalk between cancer cells and macrophages in a tumor microenvironment through in silico (computational) co-culture models. In particular, we investigate how macrophages of different polarization (M1 vs. M2) can interact with epithelial-mesenchymal plasticity of cancer cells, and conversely, how cancer cells exhibiting different phenotypes (epithelial vs. mesenchymal) can influence the polarization of macrophages. Based on interactions documented in the literature, an interaction network of cancer cells and macrophages is constructed. The steady states of the network are then analyzed. Various interactions were removed or added into the constructed-network to test the functions of those interactions. Also, parameters in the mathematical models were varied to explore their effects on the steady states of the network. In general, the interactions between cancer cells and macrophages can give rise to multiple stable steady-states for a given set of parameters and each steady state is stable against perturbations. Importantly, we show that the system can often reach one type of stable steady states where cancer cells go extinct. Our results may help inform efficient therapeutic strategies
Prognostic value of lymphocyte vascular density and e-cadherin in inflammatory breast cancer
Background: We recently evaluated four laboratory assays, vascular endothelial growth factor D (VEGF-D), E-cadherin, lymphatic vessel density (LVD) measured by podoplanin, and intra-lymphatic tumor emboli (ILTE), which showed notable differences between inflammatory breast cancer (IBC) and non-inflammatory locally advanced breast cancer (LABC). In this study we investigated the potential of the three most quantitatively measured markers, E-cadherin, LVD and VEGF-D, to predict survival in the IBC patients.
Materials and Methods: This study involved the 100 cases identified in the Inflammatory Breast Cancer Registry (IBCR) whose tumors were previously evaluated for the four assays noted above. Living patients were recontacted and survival data were available for up to 17 years. Overall survival (OS) was analyzed through the Kaplan-Meier method stratified by E-cadherin, LVD, VEGF-D, and response to chemotherapy. The differences in OS curves were compared using the log-rank test.
Results: The median OS for patients with high LVD was 6.63 years (95% CI: 4.06 to 10.14), compared to median at 10 years not reached in those with low LVD (p = 0.03). There was a trend towards a longer median OS in patients with high E-cadherin (10.14, 95% CI: 6.63 to 11.67), compared with those with low E-cadherin (6.26, 95% CI: 3.42 to undeterminable). VEGF-D levels showed no correlation with survival.
Conclusion: Low LVD significantly predicts better survival. High E-cadherin expression, as with non-IBC breast cancer and several other malignancies, tends to be associated with a better prognosis
Allelic Variation on Murine Chromosome 11 Modifies Host Inflammatory Responses and Resistance to Bacillus anthracis
Anthrax is a potentially fatal disease resulting from infection with Bacillus anthracis. The outcome of infection is influenced by pathogen-encoded virulence factors such as lethal toxin (LT), as well as by genetic variation within the host. To identify host genes controlling susceptibility to anthrax, a library of congenic mice consisting of strains with homozygous chromosomal segments from the LT-responsive CAST/Ei strain introgressed on a LT-resistant C57BL/6 (B6) background was screened for response to LT. Three congenic strains containing CAST/Ei regions of chromosome 11 were identified that displayed a rapid inflammatory response to LT similar to, but more severe than that driven by a LT-responsive allele of the inflammasome constituent NRLP1B. Importantly, increased response to LT in congenic mice correlated with greater resistance to infection by the Sterne strain of B. anthracis. The genomic region controlling the inflammatory response to LT was mapped to 66.36β74.67 Mb on chromosome 11, a region that encodes the LT-responsive CAST/Ei allele of Nlrp1b. However, known downstream effects of NLRP1B activation, including macrophage pyroptosis, cytokine release, and leukocyte infiltration could not fully explain the response to LT or the resistance to B. anthracis Sterne in congenic mice. Further, the exacerbated response in congenic mice is inherited in a recessive manner while the Nlrp1b-mediated response to LT is dominant. Finally, congenic mice displayed increased responsiveness in a model of sepsis compared with B6 mice. In total, these data suggest that allelic variation of one or more chromosome 11 genes in addition to Nlrp1b controls the severity of host response to multiple inflammatory stimuli and contributes to resistance to B. anthracis Sterne. Expression quantitative trait locus analysis revealed 25 genes within this region as high priority candidates for contributing to the host response to LT
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