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Title: Correlating Veterans' Employment Status by Analysis of Recovery from the Recovery Assessment Scale-Short Form
Creator: Avezuela-Perez, Margaret
Date: 2020
Description: Past research has examined the low employment rates in veterans with serious mental illness (SMI) (Zivin et al., 2011) and the research...
Show morePast research has examined the low employment rates in veterans with serious mental illness (SMI) (Zivin et al., 2011) and the research suggests that the benefits of employment for veterans are improved mental health symptoms, better finances, and better self-esteem (Bond et al., 2001). The specific relationship between employment and recovery from SMI in individuals has been examined (Drake et al., 2001; Bond et al., 2001; Modini et al., 2016). Previous research has not examined the correlation between recovery from SMI and employment, specifically in a population of veterans with SMI. The current study examines the relationship between recovery and employment of veterans with SMI, using the Recovery Assessment Scale (RAS) as a measure of recovery. A logistic regression analysis yielded that no relationship was found between recovery and employment status. Results of this study suggest there may be other factors affecting the relationship between these two factors. Moreover, there is the possibility that there is no relationship between recovery and employment.
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Title: Is emotion regulation a mediator between parenting skills and treatment outcome in Parent-Child Interaction Therapy?
Creator: Butler, Kristina
Date: 2020
Description: Disruptive behavior disorders are prevalent in preschool children and are associated with a range of negative developmental sequelae. There is...
Show moreDisruptive behavior disorders are prevalent in preschool children and are associated with a range of negative developmental sequelae. There is extensive evidence that Parent-Child Interaction Therapy (PCIT) is an effective behavioral parent training program for decreasing disruptive behaviors in young children. However, the mechanism that accounts for the reduction in externalizing behaviors in PCIT is not well understood. Children’s emotion regulation (ER) is one possible mechanism that accounts for treatment effectiveness. Parenting skills focused on in PCIT serve to increase warmth in caregiver-child interactions, which, in turn, lead to increases in children’s ER skills. ER also has been shown to moderate externalizing behaviors in PCIT. However, to date, there are no longitudinal studies that have examined ER as a mediator in PCIT. The aim of this study was to determine if child ER serves as a mediator between changes in parenting skills and decreases in externalizing behavior problems after PCIT treatment. A diverse sample of 67 children and their mothers participated in PCIT treatment in a community mental health center. All variables were assessed twice, at baseline and after treatment. Positive parenting skills (“Do Skills”) and negative ones (“Don’t Skills”) were assessed during a video recorded 5-minute task using the Dyadic Parent-Child Interaction Coding System. Child ER was assessed during a video recorded 5-minute clean-up task with a behavioral coding scheme adapted from previous research. Child behavior problems were measured using the Child Behavior Checklist Externalizing Scale. Difference scores used in the final analyses were calculated by subtracting the baseline score from the final assessment score for each measure.Results of linear regression analyses revealed a significant, negative relation between changes in ER and externalizing behavior problems. Findings did not support ER as a partial mediator between parenting skills and child externalizing problems. However, moderation analyses indicated that change in ER moderated the relation between change in positive parenting skills (Do Skills) and change in behavior problems, such that the interaction was significant for greater changes in ER. Specifically, increases in Do Skills led to less improvement in disruptive behaviors in children whose ER skills decreased. Also, increases in Do Skills led to greater reductions in behavior problems in children whose ER skills showed greater improvement. This study provides evidence that change in ER moderates changes in Do Skills and change in externalizing problems in PCIT. Findings also suggest that adding strategies to PCIT that focus on increasing child ER may enhance effectiveness of this treatment.
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Title: HUMAN TRAFFICKING AND THE INTERNET: EDUCATING OUR COMMUNITY OF THE GROWING PANDEMIC
Creator: Ali, Md
Date: 2020
Description: Human trafficking is a growing pandemic with many traffickers utilizing both the surface web and dark web to recruit and sell victims of human...
Show moreHuman trafficking is a growing pandemic with many traffickers utilizing both the surface web and dark web to recruit and sell victims of human trafficking. We will explore different cases regarding human trafficking as well as how traffickers are uti- lizing technology to conduct their criminal activities. We will be going over different research studies that went over new social engineering methods that technology has introduced into the world of human trafficking and coming to a statistical analysis on preventive measures to be aware of. With increasing advancements in encryption methods and communication the ease of this crime has been committed from one’s own bedroom. This thesis will be answering the question on how to minimize or remedy this atrocious criminal activity from society by analyzing all the recommendations from each study and finding possible solutions to avoid being a victim of human trafficking.
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Title: Applying Statistical Methods to Air Quality and Asthma Data in Chicago Homes
Creator: Abromitis, Kari
Date: 2020
Description: This thesis investigates one years’ worth of indoor and outdoor air pollution data collected from Chicago area homes in relation to results...
Show moreThis thesis investigates one years’ worth of indoor and outdoor air pollution data collected from Chicago area homes in relation to results from monthly asthma surveys taken by the residents of those homes. This examination involves the processing and calibration of this large dataset, basic statistical analysis, and analysis of asthma as related to variation of air pollution and air pollution resulting from nearby transportation sources. The data was collected as a part of the Breathe Easy project, which was funded by the HUD and involved IIT and Elevate Energy, a Chicago-based economic development organization that promotes building equality through climate action. The majority of the data processing and analysis were performed using Python and it is intended for continued use during the ongoing Breathe Easy project. The basic statistical analysis of this data led to initial investigations of how the variability of pollutants on a daily basis triggered asthma severity and symptoms. There were limited relationships observed between asthma symptoms and pollutant variability, and it was found to not be as important as overall pollutant levels. A second investigation was pursued to examine how the proximity to transportation, including Metra trains, freight trains, elevated rail trains, highways, bus lines, and busy roads, affected indoor and outdoor pollution levels at each home, as well as concurrent asthma outcomes. Similar to previous research, there was some relation for transportation closeness, particularly for highways and Metra trains, and pollution emitted that effects the health of nearby residents. In addition, homes that had greater air infiltration (via envelope airtightness measurements) had elevated levels of particulate matter – the pollutant most associated with transportation proximity. This thesis provides a basis for further investigations in this ongoing project and for similar asthma and air quality relationship studies.
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Title: Technology News, January 22, 1946
Creator: Illinois Institute of Technology
Date: 1946-01-22, 1946-01-22
Collection: Technology News Microfilm collection, 1928-1981

Title: Technology News, May 21, 1946
Creator: Illinois Institute of Technology
Date: 1946-05-21, 1946-05-21
Collection: Technology News Microfilm collection, 1928-1981

Title: Technology News, May 28, 1946
Creator: Illinois Institute of Technology
Date: 1946-05-28, 1946-05-28
Collection: Technology News Microfilm collection, 1928-1981

Title: PREPARE2THRIVE: A COMMUNITY-BASED PARTICIPATORY RESEARCH PILOT INTERVENTION
Creator: Guy, Arryn Aleia
Date: 2020
Description: African Americans living with HIV and serious mental illness (AALWH and SMI) experience multi-level barriers to treatment engagement including...
Show moreAfrican Americans living with HIV and serious mental illness (AALWH and SMI) experience multi-level barriers to treatment engagement including structural discrimination, HIV and SMI stigma, medical mistrust, and poor patient-provider relationships. Personal resources such as HIV treatment self-efficacy and active coping are identified in the extant literature as buffers to barriers to treatment engagement, and may be mechanisms by which individuals living with HIV engage effectively with treatment. Using Community-Based Participatory Research (CBPR) the current study piloted a culture-specific, group-level psychoeducational intervention to improve treatment engagement among AALWH and SMI (N = 16). Overall, acceptability for intervention was high (M(SD) = 33.18(5.66) [range 6-42]). Inferential statistics indicate significant increases in CD4+ counts; HIV treatment self-efficacy, perseverance; psychological appointment attendance; and instrumental support seeking. Additionally, there was a statistically significant decrease in medical appointment attendance and self-distraction coping. An increase in ART engagement, and a decrease in viral load were also observed, however these results were not statistically significant. The peer-led intervention was highly accepted by participants. Participants demonstrated increases in HIV treatment self-efficacy, psychological appointment attendance, and CD4+ counts following completion of the intervention; however, had worse medical appointment attendance. The author highlights the clinical significance of the findings here. Taken together, results support mixed outcomes for the CBPR-developed and peer-led intervention.
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Title: VERSATILE AND DYNAMIC INCENTIVE-BASED WELLNESS PROGRAM
Creator: Janik, Raymond George
Date: 2020
Description: Rising healthcare spending is prompting companies to implement health promotion programs for their employees to reduce health cost. Several...
Show moreRising healthcare spending is prompting companies to implement health promotion programs for their employees to reduce health cost. Several studies have indicated that workplace health promotion programs do not always improve employee wellbeing or reduce company healthcare cost. Focus on short-term financial results rather than long-term employee health behavior and ineffective use of incentives have been blamed for this failure.The main goal of this research is to introduce a wellness program and incentive plan with focus on changing long-term employee health behavior so it would lead to sustainable improvement in productivity and reduction in healthcare cost. The proposed program includes multiple yearly wellness follow up events, along with wellness and fitness data collection questionnaires for timely feedback and diversified outcome-based incentives. Regression models are developed to provide estimates of biometric data that are critical to performance feedback and for estimating healthcare cost savings.The proposed wellness program is currently being tested at a 700-employee lighting company in southeast united states. The healthcare cost models estimate a return on investment of $1.8 for every dollar spent on the program.
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Title: Distributed Resource Management for Wireless Networks Over Unlicensed Spectrum
Creator: Han, Mengqi
Date: 2020
Description: In the past decades, a variety of wireless networks have been deployed, e.g., long term evolution (LTE) cellular networks, wireless local...
Show moreIn the past decades, a variety of wireless networks have been deployed, e.g., long term evolution (LTE) cellular networks, wireless local network networks (WLANs), cloud radio access network (C-RANs), wireless metropolitan area networks (WMANs), wireless body area networks (WBANs) and etc.To meet the exponential growth of traffic demands and improve the network throughput, different enhancement in the MAC protocols have been proposed for the emerging networks. For example, U-LTE (Unlicensed LTE) is proposed for LTE users to aggregate the spacious unlicensed spectrum with the licensed spectrum to boost the network throughput. Meanwhile, Wi-Fi users are allowed to opportunistically bond available channels for high data rate transmissions to improve the spectrum efficiency and network throughput. But the performance of the emerging networks with the new techniques has not been well investigated. Thus, in this thesis, we comprehensively investigate the network performance in different network scenarios. In each scenario, we first develop mathematical models to identify the performance bottlenecks in the existing MAC protocols. We then propose an algorithm to intelligently tune the protocol parameters to maximize network performance. Finally, the proposed algorithm is compared with some existing algorithms. Specifically, in the first scenario, we evaluate the coexistence performance between the Wi-Fi users with channel bonding capability and the legacy users without channel bonding capability. Specifically, the channel bonding probability and the channel access delay of wireless users are first analyzed, considering the contentions among legacy and multi-channel users in the same channel and across multiple channels. Based on the analysis, the network capacity, i.e., the maximum number of traffic flows that can be supported with the bounded delay performance in a multi-channel Wi-Fi with and without channel bonding, is then derived. Based on the analytical results, we propose a heuristic bonding policythat can provide important guidelines to control the number of flows to satisfy the QoS requirement and achieve the maximum network capacity. In addition, we propose an efficient probabilistic channel aggregation scheme to maximize the network throughput under the quality of service constraints for multi-channel users with channel aggregation capability. A Proximal Policy Optimization (PPO) based approach is further applied to intelligently tune the aggregating probabilities of secondary channels to maximize the network throughput.In the second scenario, we consider that U-LTE users are coexisting with the legacy users without channel bonding capability in the same unlicensed spectrum. The throughput of both Wi-Fi and U-LTE users are both derived when U-LTE users adopting two Load Based Equipment(LBE) random access protocols and Category 4 (Cat 4) algorithm agreed in 3GPP release 13.Based on the analysis, we find that the current protocols of U-LTE users are far from perfect to achieve harmony coexistence. Subject to the system fairness constraint, the aggregate throughput of U-LTE and Wi-Fi networks is maximized based on a semi branch and bound algorithm. To make the complex optimization tractable, reinforcement learning techniques are introduced to intelligently tune the contention window size for both U-LTE and Wi-Fi users. Specifically, a cooperative learning algorithm is developed assuming that the information between different systems is exchangeable. A non-cooperative version is subsequently developed to remove the previous assumption for better practicability. Extensive simulations are conducted to demonstrate the performance of the proposed learning algorithms in contrast to the analytical upper bound under various conditions. It is shown that both proposed learning algorithms can significantly improve the total throughput performance while satisfying the fairness constraints.Finally, by considering the energy constraints, we consider an IoT network where IoT devices use adaptive p-persistent ALOHA for data transmissions. In an IoT network with energy harvesting, an IoT device can contend for channel access only when it is ready, i.e., it has data for transmission and it harvests enough energy for communications. Due to stochastic energy harvesting and random access, the number of ready devices in the network may vary. As such, an analytical framework is first developed using a discrete Markov model to analyze the average number of ready devices. Next, an optimization problem is formulated to maximize the system throughput by adapting the transmission probability p of IoT devices. Given that the wireless environment is unknown at different IoT devices, e.g., the total number of contending devices, data arrival rates of other IoT devices, a multi-agent reinforcement learning algorithm is introduced for each device to autonomously tune the transmission probability in a distributed manner. In addition, game theory is applied to design the reward function to ensure an equilibrium and to closely approach the optimal parameter setting. Numerical results show that the proposed learning algorithm can greatly improve the throughput performance comparing with other algorithms.
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Title: 3D reconstruction of lake surface using camera and lidar sensor fusion
Creator: Khan, Shahrukh
Date: 2020
Description: Global Navigation Satellite System Reflectometry (GNSS-R) relies upon detecting the GNSS signals reflected off a surface and then analyzing...
Show moreGlobal Navigation Satellite System Reflectometry (GNSS-R) relies upon detecting the GNSS signals reflected off a surface and then analyzing the reflected signal to obtain surface characteristics. GNSS-R has become one of the many additional applications of the readily available GNSS signals, alongside more traditional remote sensing of ionospheric monitoring, beyond the intended GNSS purposes of providing position, navigation, and timing estimation. In previous work, GPS signals reflected off Lake Michigan in Chicago have been collected using a specially designed portable sensor suite. The data collected is then analyzed to differentiate between surface ice and water conditions, as well as obtain other characteristic information such as surface reflectivity. The goal is to provide a way for remote sensing of seasonal ice formation beyond just satellite imagery which can be affected by cloud cover. To confirm the validity of the GNSS-R results there needs to be a separate reference against which to compare. This work demonstrates the sensor fusion between camera and lidar to reconstruct the lake surface, to provide that truth reference for comparison against the results of the GPS reflectometry signal processing. For this setup, the camera provides visual information about the lake surface, while the lidar provides distance information with respect to the sensor suite. Combining the data from the two sensors allows backward projection of the camera image to reconstruct the lake surface and its features. The backward projection relies upon knowledge of the camera's intrinsic properties alongside distance information of the features captured by the camera. Each pixel of the camera image is then transformed to its 3D position relative to the sensor system. This produces a 3D map of the lake surface, as captured by the sensors. The estimated point at which the GPS signal reflects off the surface, the specular point, is calculated by the satellite position at the time of interest and the receiver location. This point is then mapped onto the reconstructed surface to identify the exact location where the signal reflected and compare the surface visually to the results from the signal analysis.Time-varying camera-lidar-specular-point maps of the data campaigns conducted for this project are created for comparison with the GPS signal analysis. Multiple data campaigns were performed during which the Lake Michigan surface had surface ice, water or a mixture of the two. The lake surface is reconstructed for different timestamps, using the appropriate image frame and lidar frame. Combining chronologically, the changes in the lake surface can then be observed along with the movement of the specular point, due to the movement of the GPS satellites. Any satellites passing over a boundary between water and ice on the lake surface are identified and time stamped, to then be compared to the GPS signal analysis results.
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Title: The Relation Between Community Violence Exposure and Young Children's Psychopathology Symptoms
Creator: Gibson, Lynda L
Date: 2020
Description: Chronic community violence exposure (CVE) has become an everyday issue for many children living in inner-city neighborhoods. However, few...
Show moreChronic community violence exposure (CVE) has become an everyday issue for many children living in inner-city neighborhoods. However, few studies have examined the effects of CVE on symptoms of psychopathology in young children. The primary aim of this study was to examine the relation between CVE and internalizing and externalizing symptoms in preschool children. Another goal was to determine if the relations between CVE and both types of symptoms were affected by the type of exposure, the location of the event, and the relationship between the child and the individual involved in the event. A signal-contingent ecological momentary assessment (EMA) design was used in which 32 caregivers reported on their age 3-5 year-old children’s exposure to community violence, and their internalizing and externalizing symptoms for one week. A total of 152 events of community violence were reported during this period, revealing that the children were exposed to an alarmingly high frequency of these events. Results of multilevel model (MLM) analyses showed that increased frequency of momentary CVE was associated with more severe caregiver-reported internalizing and externalizing symptoms throughout one-week. Additionally, witnessed CVE, situations occurring near home, and situations involving someone known by the child strengthened the association between CVE and symptom severity. The present findings reveal that some of the long-term negative effects associated with trauma exposure occur in a shorter time-span when children are exposed to community violence on a daily basis. They also provide guidelines that can be used to inform future assessment of CVE and strategies that may be effective for intervention.
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Title: Gaussian Process Assisted Active Learning of Physical Laws
Creator: Chen, Jiuhai
Date: 2020
Description: In many areas of science and engineering, discovering the governing differential equations from the noisy experimental data is an essential...
Show moreIn many areas of science and engineering, discovering the governing differential equations from the noisy experimental data is an essential challenge. It is also a critical step in understanding the physical phenomena and prediction of the future behaviors of the systems. However, in many cases, it is expensive or time-consuming to collect experimental data. This article provides an active learning approach to estimate the unknown differential equations accurately with reduced experimental data size. We propose an adaptive design criterion combining the D-optimality and the maximin space-filling criterion. The D-optimality involves the unknown solution of the differential equations and derivatives of the solution. Gaussian process models are estimated using the available experimental data and used as surrogates of these unknown solution functions. The derivatives of the estimated Gaussian process models are derived and used to substitute the derivatives of the solution. Variable-selection-based regression methods are used to learn the differential equations from the experimental data. The proposed active learning approach is entirely data-driven and requires no tuning parameters. Through three case studies, we demonstrate the proposed approach outperforms the standard randomized design in terms of model accuracy and data economy.
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Title: THE EFFECTS OF PHYSICAL AND CHEMICAL PROPERTIES OF DOLOMITE ON DOLOMITE DECOMPOSITION
Creator: Huang, Hsiang-Jung
Date: 2020
Description: Dolomite comprises approximately two percent of the Earth’s crust and has a widespread geological distribution throughout the world. It is an...
Show moreDolomite comprises approximately two percent of the Earth’s crust and has a widespread geological distribution throughout the world. It is an abundant, low cost, and promising raw base material for many applications in industry, such as sorbents for capturing CO2 from coal gas and a heterogeneous catalyst for reducing tar content in biomass gasification. Dolomite decomposition has been intensively studied over the past decades. However, to date, there is hardly any systematic literature available that addresses the effects of naturally occurring impurities on dolomite decomposition due to the difference in various experimental setups, sample size, particle size, and so on. Therefore, this research focuses on employing a systematic and comprehensive investigation to develop a better understanding of the effects of the physical and chemical properties of raw dolomites on dolomite decomposition. This study involves experimental, theoretical, and modeling work. There are several experimental techniques utilized for the exploration of the physical and chemical properties of dolomites from different sources, such as the Thermogravimetric analysis (TGA), the X-ray powder diffraction (XRD) and the Brunauer–Emmett–Teller theory (BET), respectively. In the study, it has been discovered that the excess weight loss of samples during thermal decomposition experiments was owing to the explosive disintegration of the nature of dolomite. The physical properties of dolomites are not the main factor affecting dolomite decomposition but thermodynamic properties and crystal structure. The initial equilibrium constant of dolomite which is dominated by the amount of silicate-based impurities plays a major role in the decomposition rate. A two-stage reaction model was developed that included a reversible reaction of uniform solid ordered-disordered crystal transformation of dolomite followed by a "Quasi-Shrinking Core" reaction of disordered dolomite decomposition. This model is capable of describing the reaction rate of half-calcination of dolomite with acceptable accuracy.
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Title: ASSET PRICING AND RETURN REVERSAL IN KOREAN AND JAPANESE STOCK MARKET
Creator: Kim, Pil Joon
Date: 2020
Description: The stock market in Asia achieved a rapid development in the 1980’s, mainly in Japan and Korea. In particular, stock market in Japan and Korea...
Show moreThe stock market in Asia achieved a rapid development in the 1980’s, mainly in Japan and Korea. In particular, stock market in Japan and Korea is deeply related to the US stock market. However, in 1997, a major financial crisis hit Asia, and IMF decided to provide financial support to Korea. In addition, in 2011, a nuclear accident at the Fukushima Daiichi Nuclear Power Plant was the most severe nuclear accident since the 26 April 1986 Chernobyl disaster. Nevertheless, the Japanese and Korean markets experienced stable growths. Were Japanese and Korean stock markets truly stable and efficient? This study empirically studied market efficiency through stock market return reversal in the Japanese and Korean stock market and the characteristics of these two stock markets were compared and analyzed.Significant return reversal phenomenon was observed as a result of validating return reversal phenomenon against the stock markets in Korea and Japan. Furthermore, return reversal level differed based on the abnormal (excess) return calculation method used in the test model. Return reversal phenomenon can be found more clearly in loser portfolio than in winner portfolio in general. In particular, when the abnormal (excess) return was calculated using CAPM model, different result from existing research was observed. I also found that the Fama-French 3 factor model can compensate for the CAPM problem. I concluded that this phenomenon is observed in Korea and Japan stock market supporting DeBondt & Talher that CAPM misleads theoretical stock price return reversal and Brown and Warner (1980), who found that sophisticated CAPM do not perform better than simple model like market adjusted returns model. This is interpreted that the stock markets in Korea and Japan are not efficient and continue to have unstable factors. These findings provide full of suggestions to further research. CAPM is to explain market equilibrium price as a one-factor model, the Fama-French 3 factor model is a multi-factor model, and it can be said to more accurately describe the equilibrium price by adding size and gross value factor in describing the market equilibrium price. These results show that if Fama-French 3 factor model uses, it can solve the problem when using CAPM.The January effect is found significantly in both the Korean and Japanese markets. In the Korean stock market, the short-term seasonal reversal effect is more pronounced than in the long-term, and in the Japanese stock market, the long-term seasonal reversal effect is more pronounced than in the short-term.
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Title: THE MODERATING AND MEDIATING ROLE OF SELF-REPORTED FAMILY ACCOMMODATION ON THE RELATION BETWEEN OBSESSIVE-COMPULSIVE SYMPTOMS AND RELATIONSHIP SATISFACTION IN AN ADULT, CLINICAL SAMPLE OF INDIVIDUALS IN ROMANTIC RELATIONSHIPS
Creator: De Leonardis, Andrew J
Date: 2020
Description: Severity of obsessive-compulsive symptoms (OCS) is associated with treatment resistance, and in an interpersonal context, is associated with...
Show moreSeverity of obsessive-compulsive symptoms (OCS) is associated with treatment resistance, and in an interpersonal context, is associated with increased relationship distress and decreased relationship satisfaction. In addition, caregivers for those with clinical levels of OCS often engage in family accommodation (FA) behaviors that serve as an extension of the OCD patient’s compulsive behavior. However, the literature on the interchange of OCS, FA, and relationship satisfaction is limited in scope because it focuses mainly on the perspective of the caregiver or partner of the individual with OCD. The current study aims to address this limitation by examining OCS, FA, and relationship satisfaction variables from the perspective of the individual with OCD. Participants included 78 adults with self-reported OCD who were recruited in the US through clinics and clinicians specializing in OCD treatment, as well as from OCD non-profit organizations to target non-treatment-seeking participants. After controlling for demographic variables, results indicated the following: (1) a significant positive association between OCS and FA, (2) a significant negative association between OCS and relationship satisfaction, and (3) a lack of an interaction between FA and OCS when predicting relationship satisfaction. However, the third result was trending towards significance and may be statistically underpowered. Exploratory analyses found FA to be a partial mediator of the association of OCS and relationship satisfaction. The findings support current trends in the research literature as well as contradict extant research on the associations between OCS, FA, and relationship satisfaction. Additionally, findings continue to show the importance of addressing family accommodation in treatment of individuals with OCD.
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Title: Technology News, December 11, 1945
Creator: Illinois Institute of Technology
Date: 1945-12-11, 1945-12-11
Collection: Technology News Microfilm collection, 1928-1981

Title: Technology News, March 26, 1946
Creator: Illinois Institute of Technology
Date: 1946-03-26, 1946-03-26
Collection: Technology News Microfilm collection, 1928-1981

Title: Technology News, April 01, 1946
Creator: Illinois Institute of Technology
Date: 1946-04-01, 1946-04-01
Collection: Technology News Microfilm collection, 1928-1981

Title: Evaluation of Salmonella Proliferation on Alfalfa Sprouts during Storage at Different Temperatures
Creator: Lin, Chih Tso
Date: 2020
Description: Sprouts, a low-calorie vegetable rich in nutrition, have been a popular ingredient in many meals in the USA. They are grown either at...
Show moreSprouts, a low-calorie vegetable rich in nutrition, have been a popular ingredient in many meals in the USA. They are grown either at commercial sprout farms or at home and served raw or lightly cooked. However, sprouts are also known as a source of foodborne illness outbreaks. FDA Food Code identifies raw sprouts as a time/temperature control for safety food. However, little information is known about the growth profile of foodborne pathogens in sprouts stored at different temperatures. This study aimed at evaluating the proliferation of Salmonella in alfalfa sprouts during storage at 4, 10, and 25℃ under two different contamination routes: 1) sprouts that were inoculated with Salmonella after harvest and 2) sprouts that were grown from contaminated seeds. Alfalfa sprouts grown from uninoculated seeds and harvested after 5 days of sprouting were divided into 25-g portions. Each portion was inoculated with a cocktail of five Salmonella serovars at levels of 10^1, 10^3 or 10^5 CFU/g prior to storage at 4, 10, or 25℃. Alternatively, sprouts grown for five days from seeds spiked with 1% of seeds previously inoculated with the Salmonella cocktail were divided into 25-g portions and stored at 4, 10, or 25℃. At defined time points (Days 0, 2, 4, 7, 14, and 21), levels of Salmonella and background microflora in stored sprouts were determined by plate count. Alfalfa sprouts appeared fresh during the 21 days of storage at 4 or 10℃ but started to show signs of spoilage after 4 days of storage at 25℃. The total plate counts maintained at a level above 9 log CFU/g throughout 21 d of storage at 4 and 10℃ or during the first 7 d of storage at 25℃. Storing sprouts at 4 or 10℃ could inhibit the proliferation of Salmonella. After 21 d of storage, the Salmonella counts in inoculated sprouts decreased slightly, by 0.88 or 0.93 log units, respectively. For sprouts stored at 25℃, the Salmonella growth profile differed depending on the route of contamination and the level of Salmonella at the start of storage. In sprouts inoculated at levels of 1.41, 2.83, and 4.75 log CFU/g, the Salmonella counts increased to 6.62, 6.86, and 6.68 log units, respectively, during the first 4-7 days of storage. For alfalfa sprouts grown from contaminated seeds, the Salmonella counts remained at a level similar to that in the harvested sprouts (8.16 log CFU/g) during the first 7 d. Results from this study further the understanding of pathogen growth in sprouts and will aid in the development of guidelines for proper storage of sprouts.
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