SACM - United States of America
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Item Restricted A REVIEW OF MAGNETIC RESONANCE IMAGING-GUIDED ADAPTIVE RADIATION THERAPY: CURRENT CHALLENGES(Boston Universty, 2022) Alsufyani, Maha; Thomas, KevinRadiation Therapy (RT) is considered one of the most prevalent options for oncologic cancer treatment. However, due to changes in some patients' organs, size, shape, tumor position, or movement that may occur over the treatment period, adaptive radiotherapy (ART) was a new method introduced in 1997 (Yan et al., 1997). ART is used to correct these anatomical and functional variations by modifying plans during the treatment. Image-guided Radiotherapy (IGRT), as part of the ART process, is a technique used to detect these variations and adjust treatment plans accordingly (Sterzing et al., 2011). Currently, the IGRT technique uses onboard Cone-Beam Computed Tomography (CBCT), which is an effective technique. However, CBCT generates insufficient soft tissue contrast images to accurately distinguish between normal tissues and tumor fields. Therefore, a new method using Magnetic Resonance Imaging-Guided Adaptive Radiotherapy (MRgRT) was introduced to advance ART by providing real-time visualization of the cancer and the tissue around it (Acharya et al., 2016). To further identify and monitor anatomic motion, MRgRT offers real-time images (Chin et al., 2020). In this review, an investigation of previous studies and clinical trials was conducted to understand the challenges and limitations that can be faced by using MRgRT. The results of the study might suggest MRIgRT's potential function in enhancing radiation therapy.13 0Item Restricted DEVELOPMENT OF PSMA-TARGETED RADIOPHARMACUTICALS FOR ROUTINE CLINICAL APPLICATIONS(Texas A&M University, 2022) Abusalem, Mohammed; Ford, JohnProstate cancer (PCa) is regarded one of the most prevalent cancer diagnoses amongst men in the United States and worldwide. Moreover, PCa is the second leading cause of cancer deaths in America. Prostate specific membrane antigen (PSMA) has been recognized as a promising molecular target in the detection of PCa, which has led to the development of specific radiolabeled tracers for PCa imaging and radioligand therapy. Consequently, PSMA-targeted radiopharmaceuticals applications in molecular imaging have significantly grown in recent years, evidenced by the number of clinical studies published, and the recent U.S. Food and Drug Administration (FDA) approval of Gallium-68 labeled PSMA-11 (68Ga-PSMA-11), a positron emission tomography imaging agent for PSMA positive lesions in men with prostate cancer. In this study, the aim is to preclinically evaluate Copper-64 labeled PSMA-I&T (64Cu-PSMA-I&T), as a potential PSMA-targeted imaging agent for routine clinical applications. In vitro and in vivo biological evaluation studies will be conducted to assess the specificity and binding affinity of the radiotracer to target, as well as estimating the absorbed dose delivered to target organs via internal radiation dosimetry measurements. PSMA-I&T (for Imaging & Therapy) offers high potential as a PSMA- binding-inhibitor, and is considered one of the first theranostic tracers, as it can be radiolabeled with various radiometals for imaging or therapy of PCa. While 64Cu is a well- established clinically available PET isotope that can be produced in large batches by a cyclotron and has a relatively long half-life (12.7 hrs.), which is important to facilitate the accessibility to and overcome logistical burdens associated with the production and commercial distribution of medical radioisotopes.20 0Item Restricted A Dynamic F A Dynamic Fault Tolerance Model for Micr ance Model for Microservices Ar vices Architectur chitecture(South Dakota State University, 2019-08) Hameed Addeen, Hajar; Yi, LiuMicroservices architecture is popular for its distributive system styles due to the independent character of each of the services in the architecture. Microservices are built to be single and each service has its running process and interconnecting with a lightweight mechanism that called application programming interface (API). The interaction through microservices needs to communicate internally. Microservices are a service that is likely to become unreachable to its consumers because, in any distributed setup, communication will fail on occasions due to the number of messages passing between services. Failures can occur when the networks are unreliable, and thus the connections can be latent which may lead to failure or slow response. This might be a problem for synchronous remote calls actively waiting for a response. If they do not use a proper timeout mechanism, they may end up waiting for an extended amount of time. Applications usually set a timeout for all remote calls to avoid hanging of the whole application due to network failure or component failure. However, this timeout needs to be set carefully to make the system or microservice application to work as required. This would prevent further problems because if a remote call is waiting too long for a reply, it can slow down the system in its entirety, and if a connection timeout is extremely fast, it may ignore a response that is sent after timeout. This thesis proposes a dynamic fault tolerance (DFTM) Model to improve the stability and resilience of the microservices architecture. The Model is designed using a two-states Circuit Breaker called Switch Circuit Breaker with Markov-Chain. In addition, a modified Circuit Breaker (three states – open, closed, and half-open) to Switch Circuit Breaker (two states – open and closed) is presented here. The Circuit Breaker uses timeout to detect fault but timeouts usage hinges on assumptions about the real-time behavior of the system and awaiting process can be deduced from the occurrence of a timeout that a failure has occurred. Therefore, DFTM model adopted Markov Chain based model to detect fault without a timeout. Then, it sends the fault directly to Switch Circuit Breaker that uses a 2-states to cover the faults. An important finding is that the DFTM model presents a solution to the problem of transient failures or faults in the inter- service communication of microservices architecture. Also, it improves the performance and reliability of microservices architecture.11 0Item Restricted A study of dimensional accuracy in a partially edentulous arch by using a new alternate method to scan: An in-vitro study.(Rutgers School of Dental Medicine, 2023) Kazim, Sohil; Kamel, Mohamed; Saghiri, Mohamed Ali; Morgano, Steven; Morgano, StevenObjective: This study aims to determine the dimensional accuracy of 3D virtual casts generated by using 2D imaging (3DV) compared with a 3D scanned cast made with a table-top scanner (3DS) of a partially edentulous mandibular stone cast. The 3D scanned cast (3DS) was selected as a control because of its high precision and accuracy. Material and methods: A partially edentulous mandibular stone cast was scanned 5 times by using a 3D table-top scanner (Shining3D Dental, Zhejiang, China) to generate STL files. After a critical examination of all 5 STL 3D scans, 1 of them was chosen for the study with optimal landmarks and no surface defects. One hundred images of the mandibular stone cast were made by using a smartphone (iPhone 12 plus, Apple Inc, Cupertino, CA) from various angles. Then, the 2D images were converted to a 3D model by using the process of photogrammetry. The software used to render this process was Autodesk ReCap software (Autodesk ReCap, Inc, San Rafael, CA). The entire procedure was repeated 12 times to obtain 12 different data sets. To ensure repeatability of this alternate method to scan, all 3DV group casts were superimposed on each other to observe the difference between the superimposed casts. The selected 3D scanned cast from the 3DS group was compared with the 3DV group by using Autodesk Recap software to observe the match between the 2 groups. After completing the Autodesk Recap procedure, ImageJ software (National Institutes of Health, Bethesda, MD) was used to analyze and measure the dimensional difference between the selected 3DS cast and 3DV group. The data were analyzed by using the 1-sample t-test. Results: Twelve virtual casts of the 3DV group were overlapped on the selected 3D scanned cast which was obtained by using the table-top scanner. Significant overlaps were observed between both methods to scan for the partially edentulous mandibular stone cast (P < 0.05, CI 95%). Conclusion: The proposed method was highly accurate and comparable to a commercially available 3D table-top scanner. Clinical relevance: This new scanning technique is highly accurate and less expensive, easier to use and handle, and less space-consuming in the laboratory when compared with the results obtained from a 3D table-top scanner. Statement of problem: - High price of a 3D table-top scanner. - Size of the 3D table-top scanner.20 0Item Restricted STRUCTURAL AND MECHANISTIC INSIGHTS INTO USP10 AND USP7: CONFORMATIONAL REGULATION AND INHIBITION STRATEGIES(Wayne State University, 2025) Alshammari, Eid Salem; Zhe, YangUbiquitin-specific proteases USP10 and USP7 play crucial roles in regulating diverse cellular processes and have emerged as attractive therapeutic targets in cancer. In this dissertation, we present a multi-scale structural and molecular dynamics investigation of these deubiquitinases, combining predictive modeling, crystallographic data, molecular dynamics (MD) simulations. For USP10, which lacks a crystal structure, AlphaFold model and MD simulations revealed a stable and highly conserved USP domain, with some flexible loops surrounding the active site and the Ub-binding pocket, suggesting auto-regulatory structural elements that may control conformational regulation, substrate access, and enzymatic activity. USP10’s flexible N-terminal region contains regulatory loops that transiently interact with the catalytic domain, suggesting another layer of regulation and substrate control. Compound GL462 is a potential USP10 inhibitor, exhibiting a binding mode near the active site. Protein stability and inhibition assays confirmed GL462’s destabilizing effect on USP10 through a selective protein unfolding mechanism. Its potent inhibitory activity, positioning it as a promising lead for further development. For USP7, comparative analyses of the apo and ubiquitin-bound structures revealed that proper alignment of the catalytic triad and opening of the switching loop are key elements for USP7 activation. Classical and metadynamics simulations showed that certain mutations in the switching loop, such as H294E, stabilize an active-like state with minimal energy cost, while others, like V302K, remain energetically trapped in either an intermediate or inactive conformation, highlighting the critical role of switching loop dynamics in USP7 activation. Analysis of sixteen USP7-inhibitor complexes identified two distinct binding modes. Mode 1 compounds appear to rigidly block activation by binding to a critical region within the catalytic cleft. In contrast, Mode 2 inhibitors bind at the Thumb-Fingers interface, located at the edge of the ubiquitin-binding pocket, thereby interfering with ubiquitin binding while permitting reversible regulation. Metadynamics simulations revealed distinct energy barriers associated with these inhibitors, correlating with their conformational flexibility and mechanisms of action. Taken together, these findings reveal key structural features regulating USP10 and USP7 conformational activation, regulation, and inhibition, providing a framework for developing targeted inhibitors with therapeutic potential.14 0Item Restricted Cyber Physical Attacks and Detection MEthods in Water Distribution Systems(The University of Alabama, 2025) Hameed Addeen, Hajar; Yang, XaioModern technologies adopt Internet of Things (IoT) devices to increase water management efficiency and enhance water quality services. However, the limitations of IoT devices, such as small sizes and poor security, weaken the Water Distribution System (WDS) security and many attackers compromise the critical components of WDS. Cyber-physical attacks (CPAs) are considered one of the biggest challenges that decrease the security factors in WDS by disrupting normal operations and tampering with the critical data of the water system. Therefore, this dissertation proposes an anomaly detection method to detect cyber-physical attacks and mitigate their bad impacts on the components of WDS. First, we study the current state-of-art for the common cyber-physical attacks and common detection mechanisms for the WDS. Also, we compare CPA attacks and detection methods with emphasis on ideas, methods, evaluation results, advantages, and limitations. Second, we propose a deep learning model based on a conditional variational autoencoder (CVAE) to detect cyber-physical attacks. The CVAE model shows a highly effective way to maximize the chance of generating the desired output and detecting CPA attacks quickly. We also train CVAE on (BATADAL) real medium-sized water distribution dataset and demonstrate high-efficiency results. Experiment results indicate that our proposed method of CVAE can detect all the listed attacks with high accuracy and reduce false alarm issues. Then, we evaluate the proposed models’ performance using various metrics, including accuracy, precision, recall, and F1 score. In addition, we compare the CVAE model with existing models to detect CPA attacks, and the results show that we reach a high accuracy of 98%. Third, we designed an adversarial attack on our CVAE model to show the security risks of this attack and the negative impact on the model’s accuracy. We apply the Fast Sign gradient method to fool the CVAE model and predict the anomalies as normal data rather than anomalies. Then, we propose our novel defense approach, the CVAE defense model, to detect adversarial attacks. The CVAE defense model consists of adversarial detection and the CVAE defense models. The adversarial detection model adopts CNN and LSTM methods to classify data as adversarial or clean. The CVAE defense model takes the output of the adversarial detection model and passes it to our proposed noise generation method. After that, the noise generation method is produced and passed to the CVAE model and activation function. Finally, we calculate the Euclidean distance between the reconstructed output and input vectors and compare it to the threshold. If the output is less than the threshold, there is no attack. Otherwise, the output should be one, and there is an attack. The results show that our CVAE defense model can detect adversarial attacks and increase the performance to an overall 92%.14 0Item Restricted Advanced Mass Spectrometric Strategies for The Selective Detection of Oxidized Lipids(University of Toledo Health Science Campus, 2025-08) ALYAMI, MOHAMMED ABDULLAH A; Von Grafenstein, HermannOxidized lipids are involved in inflammation, immune responses, and disease progression, making their detection important for many fields of biomedical research. However, analyzing the oxidized lipids is difficult because of their low abundance, chemical instability, and suppression by major lipids like phosphatidylcholine (PC) in matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. This dissertation introduces analytical strategies based on selective derivatization and digital filtering to improve detection. Two complementary methods were developed. The first method, Mass-Difference Digital Filter (MDDF), uses stearic acid hydrazide to derivatize aldehyde-containing oxidized phospholipids. It monitors paired signals formed between native lipids and their hydrazones. While MDDF works well under ideal conditions, it becomes less effective when isobaric lipids interfere or when the oxidized lipids are very low in abundance. To solve these problems, the Automated Bell-Curve Selectivity Algorithm (ABSA) was developed. It uses fixed-charge Girard’s reagents (GRT, GRP, and synthesized GRB) to derivatize oxidized lipids. ABSA identifies true hydrazones by detecting a bell-shaped signal pattern across reagent concentrations, where the signal increases during optimal derivatization and decreases due to ion suppression at higher reagent levels. This method successfully detected low-abundance oxidized lipids, even when background phospholipids were present in sixteen-fold excess. In addition, peak shape analysis was performed to improve mass accuracy and signal consistency. Twelve statistical models were tested for fitting MALDI-TOF lipid peaks. The Johnson SU distribution showed the best fit for asymmetric peaks, followed by the Extended Skew Normal and Exponentially Modified Gaussian distributions. Standard symmetric models like the normal distribution did not perform well, confirming that asymmetric models are more suitable for lipid peak shapes. Overall, combining chemical derivatization with digital pattern recognition offers a practical and effective solution for detecting oxidized lipids. These methods reduce the need for complex sample preparation or chromatography and make it possible to selectively identify and quantify oxidized lipid species in complex biological samples.13 0Item Restricted Trends in and Factors Associated with Science Achievement among Fourth Graders in Saudi Arabia: A Secondary Analysis of TIMSS Data(Florida institute of technology, 2025-05) Massawe, Reda; Marcinkowski, ThomasThis secondary analysis examined trends and factors associated with science achievement among fourth-grade students in Saudi Arabia using data from the Trends in International Mathematics and Science Study (TIMSS). Between 2007 and 2019, Saudi students consistently scored below the international average in science, with female students outperforming males by more than 30 points. The study addressed two issues: (1) reasons behind Saudi students’ underperformance and (2) limited research on contributing factors. TIMSS data from 2011, 2015, and 2019 were analyzed using descriptive, correlational, and regression methods. While trends across the years were explored, only 2019 data were used for detailed regression analyses. Science achievement was the dependent variable, with 30 independent variables drawn from student, teacher, school, and home questionnaires. Data were cleaned and prepared through item and scale scoring, outlier detection, and multicollinearity checks. Findings showed that student variables contributed most to science achievement. Peer interactions, science confidence, and home study supports were consistently strong predictors. Teacher and school variables, such as emphasis on science investigation and socioeconomic composition, added modest explanatory power. Home background factors, including pre-primary education and parental occupation, also played a meaningful role. Gender-based analyses revealed differences: for males, science confidence and early education were key, while for females, school socioeconomic context and home supports had stronger effects. Study delimitations and limitations, as well as generalizability and implications were discussed. In addition to offering recommendations for further research, the findings support targeted policies that enhance early learning, peer engagement, and equitable learning environments.7 0Item Restricted SPORT EVENT PRESTIGE CONCEPTUALIZATION: SPECTATOR, PARTICIPANT, AND VOLUNTEER PERCEPTIONS OF VARIOUS SPORT EVENT SIZES(University of Florida, 2025) Khan, Hamza; Kaplanidou, KyriakiThis study aims to provide a comprehensive conceptualization of sport event prestige by examining the perspectives of various sport consumer groups. Specifically, it seeks to analyze how the various sport event consumers (e.g., sport fans, sport event participants, and volunteers) perceive and interpret the notion of sport event prestige in the context of sporting events. By integrating insights from these diverse groups, the study seeks to develop a precise understanding of the concept of sport event prestige. To achieve this, the study adopted a qualitative methodology, where semi-structured interviews were used to understand the perception of different sport consumer groups on how they define prestige. The results revealed that prestige was defined differently across consumer groups. For participants, prestige was perceived as tied to achievement and sacrifice; spectators emphasized emotional experience and event atmosphere; and volunteers associated prestige with contribution, and future opportunities. Moreover, sport event prestige was found to have impacts beyond the consumer groups, with positive effects observed on the hosting nation's economy and tourism. However, the findings also indicated that the impact of prestige is not always positive, negative impacts associated with the economy and crime were also reported. These insights provide a better understanding of the roles that prestigious sport events play among sport consumer groups and the hosting nation. This study will help sport managers and event organizers seeking to enhance event value and stakeholder engagement by understanding how the term "prestige" functions across different sport event sizes and various stakeholder groups.8 0Item Restricted EVALUATION OF THE SAFETY IMPACTS OF SPEED LIMIT INCREASES ALONG HORIZONTAL CURVES ON RURAL FREEWAYS IN MICHIGAN(Michigan State University, 2025) Alsady, Abdullah S; Savolainen, Peter TIn May 2017, the State of Michigan enacted legislation that increased the maximum posted speed limit from 70 mph to 75 mph on approximately 614 miles of rural limited-access freeways. While previous studies have evaluated the broader operational and safety impacts of this change, limited research has focused on its effects on roadway segments with geometric constraints—particularly horizontal curves. These curves are recognized as high-risk locations due to reduced sight distance, elevated lateral acceleration demands, and speed compliance challenges. This study addresses that gap by assessing the safety impacts of the speed limit increase specifically on horizontal curves. The analysis used crash data spanning five years before (2012–2016) and five years after (2018–2022) the speed limit change. A total of 116 horizontal curve segments were selected as treatment sites, while 81 comparable segments served as controls. Two analytical approach was employed: a cross-sectional regression analysis to identify key predictors of crash frequency and severity, and a before–after evaluation using the Empirical Bayes (EB) method to adjust for regression-to-the-mean and other confounding factors. Site-specific Safety Performance Functions (SPFs) were developed using data from control sites to predict expected crashes across total crashes, fatal and incapacitating injury crashes (KA). The EB analysis revealed a 46.4% statistically significant increase in total crashes across all treatment sites after the speed limit increase. KA crashes rose by 36.5%, though this increase was not statistically significant. In summary, this study provides strong empirical evidence that speed limit increases on horizontal curves can lead to higher crash frequencies. The findings emphasize the importance of incorporating geometric assessments and targeted safety countermeasures—such as advisory speed signs—when modifying speed policies. These insights are especially relevant for transportation agencies seeking to enhance safety while maintaining efficient travel on rural freeway networks.