In this paper vibratory crack response is compared to that produced by volumetric changes in foundation soils induced by natural events. These natural phenomena include changes in the water table, changes in soil moisture, and formation of ice lenses to name a few. Previous papers have compared vibratory responses of...
This paper describes the technology and methods deployed in the continuous autonomous remote monitoring of cracks in interior and exterior walls of a residence near a limestone quarry. The objective is to quantitatively compare crack response due to blast-induced ground motion to that induced by diurnal temperature changes, weather fronts,...
Cosmetic and structural cracks are a large concern for homeowners. Although these cracks can develop from a variety of causes: differential foundation settlement, occupant activity, climatological effects, as well as dynamic events, people tend to look to dynamic events like blasting, construction, or traffic vibrations to be the culprit. This...
The notion of blasting, even in a controlled setting such as a limestone quarry, can be alarming to residents and business owners within earshot. Because humans are inherently sensitive to blast-induced vibrations, they perceive that the structures in which they live in are equally sensitive. The goal of this project...
This appendix contains all software used to program the MICA2 motes for Version 1 of the MICA2-based wireless ACM system. This appendix is organized by software directory and only the modified files are included.
Autonomous Crack Monitoring (ACM) and Autonomous Crack Propagation Sensing (ACPS) are two types of structural health monitoring in which characteristics of cracks are recorded over long periods of time. ACM seeks to correlate changes in widths of cosmetic cracks in structures to nearby blasting or construction vibration activity for the...
This manual describes use of a new hybrid autonomous crack and structural response monitoring (ACSM) system. It is designed as a low cost alternative to the research grade version employing SOMAT’s eDAQ data recording system. The concept is to combine a new field portable, 24 bit, 12 channel seismograph with...
This paper describes the details of installation and operation of a commercially- available wireless system to measure response of an interior cosmetic crack in a residential structure over a period of a year. Wireless data loggers managed the response of low power draw potentiometers that measured micrometer changes in crack...
The purpose of this comparative field qualification is to demonstrate the new Kelunji EchoPro
hybrid ACSM system and its performance relative to the eDAQ and eko Motes systems. These three
systems are installed at a test site in Sycamore, IL, adjacent to an active quarry. Data for this report was...
Despite a relatively mature technology for its control, corrosion caused by stray current from electrified rapid-transit systems costs the United States approximately $500 million annually. Part of that cost is the result of corrosion of the electrified rapid-transit system itself, and part is the result of corrosion on neighboring infrastructure...
The finite element method is used to investigate failure mechanisms in pin-hanger connection in aging highway bridges. Bridge pins and hangers are typically considered as critical elements whose failure may result in partial or entire collapse of the structure. The primary function of a pin-hanger connection is to allow for...
This report shows the results of acoustic emission (AE) monitoring, and provides additional information on the nature of the ultrasonic indications in the north east trunnion shaft.
A remote global monitoring system is being operated on a 65 year old lift bridge in Sturgeon Bay Wisconsin. The system uses both strain gages and clinometers to continuously monitor the "health" of the fracture critical components of the bridge. Ruggedized miniaturized data loggers are locally mounted on the structure...
Current bridge condition determination is based almost entirely on the use of visual inspection. This approach to bridge inspection provides data that is subjective and not traceable. Nondestructive evaluation (NDE) is a tool that in actuality is little used on bridges, but could eliminate much of the subjectivity of the...
This technical report shows the findings of acoustic emission and strain gage monitoring tests conducted by research engineers of Infrastructure Technology Institute from Northwestern University on April 18, 1997 in Sacramento, California.
This report includes the findings of acoustic emission (AE) tests on the Fremont tied arch bridge in Portland Oregon conducted by research engineers from the Infrastructure Technology Institute of Northwestern University on March 24th, 1997.
This paper describes application of AE monitoring techniques to localize the sources of large noises in civil structures. These noises occur during operation of moveable portions of a structure in such things as lift bridges and moveable sports stadium roofs. The use of straightforward AE monitoring techniques can provide clear...
Kosnik, D. E., Northwestern University . Infrastructure Technology Institute, Department of Civil Environmental Engineering, Robert R. McCormick School of Engineering Applied Science. (2008). A new approach to acoustic emission testing of difficult-to-reach steel bridge details. Evanston, Illinois: Infrastructure Technology Institute/Department of Civil & Environmental Engineering.
Acoustic emission (AE) testing was used to identify the source of audible “bangs” generated during opening and closing of a large, double-leaf rolling-lift bascule bridge. The data were analyzed using a combination of well-established AE
techniques, including first hit analysis (FHA), planar location analysis, and linear location analysis. The FHA...
Scour is by far the primary cause of bridge failures in the United States. Scour and other hydraulic effects are particularly threatening because the deterioration is often invisible, hidden beneath turbid water. Many scour monitoring methods attempt to measure the development of scour pockets themselves. However, this is difficult due...
Acoustic emission (AE) testing was deployed on details of two large steel Interstate Highway bridges: one cantilever through-truss and one trapezoidal box girder bridge. Quantitative measurements of activity levels at known and suspected crack locations were made by monitoring AE under normal service loads (e.g., live traffic and wind). AE...
The underutilized tropical fruit tree, “cempedak” (Artocarpus integer (Thunb.) Merr. , Moraceae), is a major crop in Malaysia but the distribution of genetic diversity in the crop and its putative wild progenitor, “bangkong” (Artocarpus integer var. silvestris Corner), have not been studied. To investigate the diversity and origins of cempedak,...
Current ecological restoration efforts seek to restore a target community, maximize biodiversity or provide habitat for rare species. In practice, restoration ecology is often initiated and sustained without knowledge or reverence to the belowground ecosystem processes, though these processes often subtend the long-term sustainability of aboveground and belowground ecological communities.
Past efforts to reintroduce the native legume species Desmodium glutinosum and Lespedeza violacea into restored woodlands have not produced self-sustaining populations. Proposed factors preventing reintroduction include herbivory, persistent environmental effects of invasive shrubs, poor performance of commercial Rhizobium inoculants, and competitive displacement associated with elevated nitrogen availability. To address these...
Pollination is a reproductive necessity in the majority of the world’s flowering plants. Pollen limitation threatens plant reproduction, particularly in self-incompatible species. Although assessing pollen limitation usually requires pollen supplementation experiments, alternative methods support the findings of traditional pollen supplementation experiments.
Pollination is a reproductive necessity in the majority of the world’s flowering plants. Pollen limitation threatens plant reproduction, particularly in self-incompatible species. Although assessing pollen limitation usually requires pollen supplementation experiments, alternative methods support the findings of traditional pollen supplementation experiments.
Two experiments were conducted to assess the germination, growth, and survival of Cirsium pitcheri Torr. ex Eaton T & G in the Chicagoland region. The first experiment involved growing seeds from various native populations to determine tolerance for the current Chicagoland climate. The second experiment tested three of the populations...
Habitat fragmentation can alter the conditions of natural plant populations, introducing novel selective pressures. The ability of a population to respond to environmental change can be inferred by assessing the population’s genetic diversity and the heritability of traits thought to be under selection.
Identifying factors that shape the spatial distribution of genetic variation within and among natural populations is crucial to understanding many population> and landscape>level processes. In this study, I characterize the strength and extent of spatial genetic structure in Oenothera harringtonii (Onagraceae), an insect>pollinated, gravity>dispersed herb endemic to the grasslands of...
The tallgrass prairie once dominated much of the mid-western United States. Today, this highly productive system has been severely reduced, contributing to an array of environmental problems. The recent renaissance in natural area restoration and stewardship of the tallgrass prairie in the Chicago Wilderness region (Illinois, USA), especially in the...
Nitrogen (N) deposition can alter belowground microbial communities, especially ectomycorrhizal (ECM) fungi, resulting in a reduced ability of associated trees to access organic nutrients. This study tested whether N addition decreases ECM species richness and shifts ECM species composition across spatial scales in a subtropical slash pine (Pinus elliottii) plantation...
The environmental and plant physiological correlates of plant growth and reproductive effort in the locally threatened orchid, Cypripedium candidum Muhl. ex Willd were examined in the context of a conceptual model of demographic and reproductive trade-offs, focusing on three Illinois populations. This study addresses the current status and long-term trends...
Plant-aphid systems provide a valuable opportunity for studying the ecological consequences of land use change for interacting species. The North American tallgrass prairie has undergone severe reduction and fragmentation due to agricultural development. The prairie perennial Echinacea angustifolia, a model system for studying population-level effects of habitat fragmentation, hosts a...
The introduction of non-native pests in general, and invasive plants in particular, has been receiving increasing interest by scientists, environmental groups, and to a certain extent the general public. Deleterious effects from the release of such alien species include threats to the environment, national economies, and even human health. The...
Underutilized crops have the potential to economically benefit developing countries and to improve global food security. Breadfruit (Artocarpus altilis, Moraceae) is one such crop that can provide essential nutrients and requires relatively low-energy input to maintain compared to major crops. Humans have selected for many cultivars of breadfruit since its...
With increasing urbanization and creation of novel habitat types, green roofs can provide usable habitat for many species. To date, most research on green roofs has focused on minimizing the environmental impacts of buildings but little is known about the ecological services they provide. Previous research has shown that although...
Hybridization is an important evolutionary pathway to genetic diversity, fitness, and ultimately to the emergence of new species. In contrast, hybridization between a native and an introduced species can lead to a loss of locally adapted gene complexes and ultimately to the extinction of the native. In the last decade,...
Once widespread throughout southern Wisconsin, Quercus savannas are now one of the most endangered communities due to fire suppression and increasing landscape fragmentation. These plant communities are also highly susceptible to invasions by nonnative, exotic species. Understanding the mechanisms of exotic species invasion has been the focus of numerous studies....
Fire is an agent of ecosystem change that has played a critical role in shaping the tallgrass prairie ecosystem. Periodic prescribed fire maintains the prairie by removing woody and invasive plant species, and stimulating growth of native herbaceous species. Fire’s beneficial effect on the tallgrass prairie aboveground community, in terms...
Due to concerns about population declines and habitat destruction, secretive marsh birds (SMBs) are of high conservation concern at state, regional, and national levels. Gaps in research on SMB habitat pose barriers to conservation and wetland restoration efforts.
Restoration managers may select seed from a variety sources for their restoration projects. If the purchased seed is not of the local ecotype, land managers run the risk of poor establishment in the short-term and outcrossing between local and non-local ecotypes, genetic swamping, and the loss of local genetic diversity...
Understanding how root traits vary within and among species, and how they respond to heterogeneous environments, can provide important insight into functional plant attributes that influence plant survival in competitive environments. Selecting plant material with root traits that will support its survival in competitive environments may help improve the outcomes...
The prairie grasses Andropogon gerardii and Sorghastrum nutans have seeds with awns that twist in response to changes in humidity. The humidity-sensitive, or hygroscopic, part of the awn twists, moving the bent, passive portion in an arc. This trait has been demonstrated to improve seedling recruitment in other grass species...
Trees in urban areas offer ecosystem services like carbon sequestration, storm water attenuation, reduction of energy used in buildings and wildlife habitat. Cities invest substantial funds and resources to maintain a healthy urban forest, and much research has been done to improve its resiliency and sustainability. Studies have been done...
Because long-chain n-alkanes (n-C21 to n-C37) are found in the epicuticular leaf waxes of all vascular plants and are stable, long-lived molecules, the study of their molecular and isotopic compositions stands to serve as a potentially powerful tool in the fields of modern chemotaxonomy and paleoecology. This study attempts to...
Understanding the factors that drive the maintenance of polymorphisms in plant populations has long been of interest to evolutionary biology. Variation in floral traits has often been attributed to selection by pollinators, but recent evidence suggests that other biotic and abiotic agents may also contribute to floral trait differentiation. In...
Climate change, whether referring to historic ice ages or contemporary shifts in global climate patterns, has been linked to wide-ranging and regionally variable changes in biotic communities.
After large-scale disturbances such as fire, seeding can be necessary to reestablish a plant community and prevent soil erosion. While native plants are ideal for providing ecosystem services and supporting wildlife, currently seeded natives often fail to establish in disturbed landscapes. Further, reseeding with native plants is often hindered by...
Nearly a quarter of visits to the Emergency Department are for conditions that could have been managed via outpatient treatment; improvements that allow patients to quickly recognize and receive appropriate treatment are crucial. The growing popularity of mobile technology creates new opportunities for real-time adaptive medical intervention, and the simultaneous...
The diverse circuits and functional contributions of the basal ganglia, coupled with known differences in dopaminergic function in patients with schizophrenia, suggest they may be an important contributor to the etiology of the hallmark symptoms and cognitive dysfunction experienced by these patients. Using activation-likelihood-estimation meta-analysis of functional imaging research, we...
We investigated the racial content of perceivers’ mental images of different socioeconomic categories. We selected participants who were either high or low in prejudice toward the poor. These participants saw 400 pairs of visually noisy face images. Depending on condition, participants chose the face that looked like a poor person,...
Many preventable behaviors contribute to adolescent mortality and morbidity. Non-adherence to preventive measures represents a challenge and has been associated with worse health outcomes in this population. The widespread use of electronic communication technologies by adolescents, particularly the use of text messaging (short message service, SMS) and mobile phones, presents...
Metabolic syndrome has become a major public health challenge worldwide. The association between metabolic syndrome and DNA methylation is of great research interest. We constructed a binomial model to investigate the association between a metabolic syndrome index and DNA methylation in the Normative Aging Study. We applied the Iterative Sure...
The Affordable Care Act (ACA) has expanded health coverage for thousands of Illinois residents. Expanded coverage, however, does not guarantee appropriate health care. Diabetes and its ocular complications serve as an example of how providers in underserved urban areas may not be able to keep up with new demand for...
When making serial predictions in a binary decision task, there is a clear tendency to assume that after a series of the same external outcome (e.g., heads in a coin flip), the next outcome will be the opposing one (e.g., tails), even when the outcomes are independent of one another....
Electronic and vibrational correlations report on the dynamics and structure of molecular species, yet revealing these correlations experimentally has proved extremely challenging. Here, we demonstrate a method that probes correlations between states within the vibrational and electronic manifold with quantum coherence selectivity. Specifically, we measure a fully coherent four-dimensional spectrum...
In the United States, African-Americans’ (AAs) HIV infection rates are higher than any other racial group, and AA men who have sex with women (MSW) are a significant proportion of new cases. There is little research into AA MSW HIV/AIDS knowledge, barriers, and facilitators of HIV testing in Chicago. We...
Acoustic stimulation methods applied during sleep in young adults can increase slow wave activity (SWA) and improve sleep-dependent memory retention. It is unknown whether this approach enhances SWA and memory in older adults, who generally have reduced SWA compared to younger adults. Additionally, older adults are at risk for age-related...
Transposable elements (TEs) have been recognized as potentially powerful drivers of genomic evolutionary change, but factors affecting their mobility and regulation remain poorly understood. Chaperones such as Hsp90 buffer environmental perturbations by regulating protein conformation, but are also part of the PIWI-interacting RNA pathway, which regulates genomic instability arising from...
Since Reduced Emissions from Deforestation and Degradation “Plus” (REDD+) starting gaining traction in the UN climate negotiations in 2007, its architects and scholars have grappled with its community-level justice implications. On the one hand, supporters argue that REDD+ will help the environment and forest-dependent communities by generating payments for forest...
US surveillance of sexually transmitted diseases (STDs) is often delayed and incomplete which creates missed opportunities to identify and respond to trends in disease. Internet search engine data has the potential to be an efficient, economical and representative enhancement to the established surveillance system. Google Trends allows the download of...
Cathode degradation is a key factor that limits the lifetime of Li-ion batteries. To identify functional coatings that can suppress this degradation, we present a high-throughput density functional theory based framework which consists of reaction models that describe thermodynamic and electrochemical stabilities, and acid-scavenging capabilities of materials. Screening more than...
Quantum frequency conversion (QFC) of photonic signals preserves quantum information while simultaneously changing the signal wavelength. A common application of QFC is to translate the wavelength of a signal compatible with the current fiber-optic infrastructure to a shorter wavelength more compatible with high-quality single-photon detectors and optical memories. Recent work...
In Sub-Saharan Africa, epidemiological studies have reported an increasing burden of non-communicable diseases (NCD) among people living with HIV. NCD management can be feasibly integrated into HIV care; however, clinic readiness to provide NCD services in these settings should first be assessed and gaps in care identified. A cross-sectional survey...
A very active area of materials research is to devise methods that use machine learning to automatically extract predictive models from existing materials data. While prior examples have demonstrated successful models for some applications, many more applications exist where machine learning can make a strong impact. To enable faster development...
Air within the bladder wall, or bladder pneumatosis, is a very rare finding typically resulting from an infectious etiology, as in emphysematous cystitis (EC). However, there have been reports of bladder pneumatosis occurring without clear infectious origins. We present a case of a female patient found to have concurrent bladder...
In 2015, the United States Preventive Services Task Force (USPSTF) recommended targeted screening for prediabetes and diabetes (dysglycemia) in adults who are aged 40 to 70 y old and overweight or obese. Given increasing prevalence of dysglycemia at younger ages and lower body weight, particularly among racial/ethnic minorities, we sought...
Extracellular vesicles (EVs) mediate intercellular communication through transfer of RNA and protein between cells. Thus, understanding how cargo molecules are loaded and delivered by EVs is of central importance for elucidating the biological roles of EVs and developing EV-based therapeutics. While some motifs modulating the loading of biomolecular cargo into...
The broad-based implementation of thermoelectric materials in converting heat to electricity hinges on the achievement of high conversion efficiency. Here we demonstrate a thermoelectric figure of merit ZT of 2.5 at 923 K by the cumulative integration of several performance-enhancing concepts in a single material system. Using non-equilibrium processing we show...
Compressive sensing allows signals to be efficiently captured by exploiting their inherent sparsity. Here we implement sparse sampling to capture the electronic structure and ultrafast dynamics of molecular systems using phase-resolved 2D coherent spectroscopy. Until now, 2D spectroscopy has been hampered by its reliance on array detectors that operate in...
The current study tested competing predictions regarding the effect of mortality salience on delay discounting. One prediction, based on evolutionary considerations, was that reminders of death increase the value of the present. Another prediction, based in part on construal level theory, was that reminders of death increase the value of...
Infants’ initially broad links between language and object categories are increasingly tuned, becoming more precise by the end of their first year. In a longitudinal study, we asked whether individual differences in the precision of infants’ links at 12 months of age are related to vocabulary development. We found that,...
This article summarizes an investigation of the structural response of a brick façade home in New Mexico. The subject Ricter residence was located some 1100 to 1400 ft away from an aggregate quarry, and was subjected to a maximum peak particle velocity and air blast over pressure of 0.29 ips...
The genetic variants underlying complex traits are often elusive even in powerful model organisms such as Caenorhabditis elegans with controlled genetic backgrounds and environmental conditions. Two major contributing factors are: (1) the lack of statistical power from measuring the phenotypes of small numbers of individuals, and (2) the use of...
We describe an approach to optical non-reciprocity that exploits the local helicity of evanescent electric fields in axisymmetric resonators. By interfacing an optical cavity to helicity-sensitive transitions, such as Zeeman levels in a quantum dot, light transmission through a waveguide becomes direction-dependent when the state degeneracy is lifted. Using a...
Slides for a workshop for Northwestern University on sharing and preserving research findings using the library's resources. This workshop was delivered at Computational Research Day 2017.
One of the most notable recent developments in survey research is the increased usage of online convenience samples
drawn from Amazon’s Mechanical Turk (MTurk). While scholars have noted various social and political differences (e.g.,
age, partisanship) between MTurk and population-based samples, the breadth and depth of these variations remain unclear....
Recent work using the eye movement monitoring technique has demonstrated that when people are engaged in thought they tend to disengage from the external world by blinking or fixating on an empty portion of the visual field, such as a blank wall, or out the window at the sky. This...
A randomized experiment was conducted to assess the effectiveness of three forms of e-mail appeals to prospective members of a newly formed professional group. The baseline condition consisted of an impersonal appeal; prospective members were sent a mass e-mail encouraging them to join. Participants in the personal condition received an...
Impairments in the social use of language, or pragmatics, constitute a core characteris-tic of autism. Problems with pragmatic language have also been documented in fragile X syndrome (FXS), a monogenic condition that is the most common known genetic cause of autism. Evidence suggests that social cognitive ability, or theory of...
The endothelial cell (EC) lining of the pulmonary vascular system forms a semipermeable barrier between blood and the interstitium and regulates various critical biochemical functions. Collectively, it represents a prototypical biomechanical system, where the complex hierarchical architecture, from the molecular scale to the cellular and tissue level, has an intimate...
In 2015, as part of the Reproducibility Project: Cancer Biology, we published a
Registered Report (Kandela et al., 2015) that described how we intended to replicate selected experiments from the paper “Coadministration of a tumor-penetrating peptide enhances the efficacy of cancer drugs“ (Sugahara et al., 2010). Here we report the...
Recent studies in quantum biology suggest that quantum mechanics help us to explore quantum processes in biological system. Here, we demonstrate generation of photon pairs through spontaneous four-wave mixing process in naturally occurring fluorescent proteins. We develop a general empirical method for analyzing the relative strength of nonlinear optical interaction...
What makes a musician? In this review, we discuss innate and experience-dependent factors that mold the musician brain in addition to presenting new data in children that indicate that some neural enhancements in musicians unfold with continued training over development. We begin by addressing effects of training on musical expertise,...
The mechanisms underlying the discovery of abstract rules like those found in natural language may be evolutionarily tuned to speech, according to previous research. When infants hear speech sounds, they can learn rules that govern their combination, but when they hear non-speech sounds such as sine-wave tones, they fail to...
Topologically non-trivial spin textures form a fundamental paradigm in solid-state physics and present unique opportunities to explore exciting phenomena such as the topological Hall effect. One such texture is a skyrmion, in which the spins can be mapped to point in all directions wrapping around a sphere. Understanding the formation...
Increasing evidence points to associations between light-dark exposure patterns, feeding behavior, and metabolism. This study aimed to determine the acute effects of 3 hours of morning versus evening blue-enriched light exposure compared to dim light on hunger, met-abolic function, and physiological arousal. Nineteen healthy adults completed this 4-day inpatient protocol...
The causes and consequences of geophagy, the craving and consumption of earth, remain enigmatic, despite its recognition as a behavior with public health implications. Iron deficiency has been proposed as both a cause and consequence of geophagy, but methodological limitations have precluded a decisive investigation into this relationship. Here we...
EGFR and cMET cross-talk is involved in breast cancer (BC) progression and resistance to different targeted therapies, however little is known about the co-expression patterns of EGFR and cMET or its prognostic significance in BC. Protein levels of EGFR, cMET and their phosphorylated proteins were measured in 825 BC samples...
Over the course of tumor growth, cancer cells interact with normal cells via processes that are difficult to understand by experiment alone. This challenge is particularly pronounced at early stages of tumor formation, when experimental observation is most limited. Eluci-dating such interactions could inform both understanding of cancer and clinical... and Tumor growth involves a dynamic interplay between cancer cells and host cells, which col-lectively form a tumor microenvironmental network that either suppresses or promotes tumor growth under different conditions. The transition from tumor suppression to tumor pro-motion is mediated by a tumor-induced shift in the local immune state, and despite...
The R package COPASutils provides a logical workflow for the reading, processing, and visualization of data obtained from the Union Biometrica Complex Object Parametric Analyzer and Sorter (COPAS) or the BioSorter large-particle flow cytometers. Data obtained from these powerful experimental platforms can be unwieldy, leading to difficulties in the ability...
We report on a diffusive analysis of the motion of flagellate protozoa species. These parasites are the etiological agents of neglected tropical diseases: leishmaniasis caused by Leishmania amazonensis and Leishmania braziliensis, African sleeping sickness caused by Trypanosoma brucei, and Chagas disease caused by Trypanosoma cruzi. By tracking the positions of...
Touch screen devices such as smartphones and tablets are now ubiquitous in the lives of American children. These devices permit very young children to engage interactively in an intuitive fashion with actions as simple as touching, swiping and pinching. Yet, we know little about the role these devices play in...