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No Difference in Pullout Strength Between a Bio-inductive Implant and a Semitendinosus Tendon Graft in a Biomechanical Study of Medial Patellofemoral Ligament Repair Augmentation
Get PDFPurpose: To compare the pullout strength of a bio-inductive implant (BI) used to augment a medial patellofemoral ligament (MPFL) repair with the pullout strength of semitendinosus graft in a biomechanical cadaveric model. Methods: Six matched pairs of cadavers (12 knees) were used in the biomechanical testing comparing semitendinosus tendon (Semi-T) versus a BI. The Semi-T was harvested from 1 of the matched pairs. A standard double-bundle technique using 2 sockets in the upper two-thirds of the patella 15 mm apart was performed. After docking of the graft into the patella, the patella was dissected free of soft tissues and potted into a fixture to allow mechanical pull parallel to the transverse axis of the patella. The construct was pulled to failure. Results: There was no statistically significant difference in pullout strength (P = .77) between the BI group (249.3 ± 36.3 N) and Semi-T group (235.0 ± 113.6 N) double-bundle constructs. In the Semi-T group, 50% of the specimens (3 of 6 knees) failed via anchor pullout and a fourth specimen failed at the suture-anchor interface (16.7%), whereas in the BI group, 16.7% of the specimens (1 of 6 knees) failed by anchor pullout. Although the Semi-T group (49.5 ± 14.1 N/mm) showed significantly greater stiffness than the BI group (13.8 ± 0.6 N/mm, P \u3c .01), pullout strength in the Semi-T group was highly variable: 50% of the specimens (3 of 6 knees) with semitendinosus constructs failed at 5 mm of displacement or less via graft or anchor pullout. Maximum load, displacement at failure, stiffness, and load at 5 mm were compared between the augmented and non-augmented control specimens using a 2-tailed non-equal variance Student t test. For all comparisons, P \u3c .05 was considered to indicate a statistically significant difference. Conclusions: In this biomechanical study, augmentation of an MPFL reconstruction using a common double-bundle technique with a BI had the same pullout strength as a semitendinosus graft using the same technique in cadaveric knees. Clinical Relevance: MPFL repair after a patellar dislocation may be inadequate to restore the strength of the native MPFL and prevent recurrent patellar instability. Recurrent instability of the patella can result in progressive injury to the soft tissue and articular cartilage of the patella and femur. It is important to study the techniques used for MPFL repair to continually improve patient outcomes. Further testing of these additional techniques and clinical studies are needed to evaluate the implants used to augment MPFL repairs
Using data mining to analyze job reviews
Get PDFJob review websites like Glassdoor are not always clear on how well the company operates, especially as viewed from differing levels of employment. For instance, a middle or upper manager from Amazon may have an overall positive review of the company with minor issues about it, but someone who works in the warehouse may have a mixed experience. To solve this issue and determine any correlation between employee level and their review, data mining techniques were utilized such as website scraping and neural network training to develop a model that analyzes employee reviews
The Impact of Stress During Adolescence and the Prevalence of Pediatric Obesity
Get PDFObesity is a chronic condition that can be attributed to myriad factors including socioeconomic status, biological risk factors, and various environmental factors. These factors can be considered stress factors, and exposure to various levels of stress can impact the development of stress within the pediatric patients. The purpose of this study is to assess the association between the environmental, mental, social, physical, and psychological stress adolescents are exposed to and how they contribute to the prevalence of pediatric obesity throughout the United States. Understanding these risk factors can help us as a community and most importantly as clinicians develop better insight to our patients as a whole and therefore be able to provide better, well rounded care
Unveiling the Impact: Structural Racism and Childhood Lead Exposure\u27s Health Consequences in Philadelphia
Get PDFChildhood lead exposure poses a significant risk to health and well-being, adversely affecting brain function, nervous system development, and behavioral patterns. This study examines the health disparities and inequities associated with childhood lead exposure in Philadelphia, focusing on structural racism and residential segregation as crucial lenses for analysis. By delving into the sociocultural context of lead exposure, this study underscores the imperative of collaborative efforts among stakeholders to safeguard Philadelphia\u27s most vulnerable populations. Healthcare professionals and policymakers play pivotal roles in enhancing funding and prevention strategies. Addressing this issue through the prism of structural racism allows for the identification and rectification of systemic and institutional factors contributing to health disparities. Through stakeholder collaboration and historical insights, this review aims to offer guidance for shielding the city\u27s most at-risk children from lead exposure
Trichotillomania Case Report
Get PDFTrichotillomania is a psycho-dermatologic disorder involving self-inflicted hair loss through pulling. Often complicated by anxiety and depression. Multifactorial etiology and limited evidence-based treatment options makes management difficult. Treatment approaches include a combination of pharmacotherapy, CBT, HRT, and ACT. Case presentation involves a 24-year-old female, diagnosed with treatment-resistant trichotillomania who achieved remission and hair regrowth through mindset reframing, physical barriers, and community support. Novel approaches focusing on mindset and community support can yield positive outcomes
HOSPITAL PROVIDER KNOWLEDGE OF BEHAVIORAL FUNCTION AND MANAGEMENT OF SEVERE BEHAVIOR FOR PATIENTS WITH AUTISM
Get PDFHospital patients with autism spectrum disorder (ASD) may engage in various topographies of severe behavior, with higher rates of restraint implemented than for their neurotypical counterparts. Qualitative research suggests that physician knowledge of function-based intervention is limited. Multidisciplinary behavior management teams were developed to decrease restraint across general hospital patients. In Study 1, the research team developed the Knowledge of Behavioral Function (KoBF) survey measure, using an iterative user-centered development process and administered the measure to multidisciplinary physicians and trainees. Results indicated low knowledge of behavioral function, with a mean percent correct of 66.60% on close-ended survey items and 14% correct on open-ended vignette items. Years of experience and discipline were each not significantly associated with knowledge of behavioral function. Despite low function-based knowledge, 91.10% of participants demonstrated adequate knowledge of autism and these scores were not significantly correlated. In Study 2, focus group discussions with behavioral management team members highlighted differences in team purposes, procedures, and training across hospitals. Although participants still described using restraint, they considered alternative strategies to restraint and indicated areas for future training and team improvements. Study findings may inform development of ASD-focused, function-based training to improve hospital standard of care for autistic patients. Keywords: Severe behavior, autism, behavioral function, hospita
Maackia Amurensis Seed Lectin (MASL) and soluble human podoplanin (shPDPN) Sequence Analysis and Effects on Human Oral Squamous Cell Carcinoma (OSCC) Cell Migration and Viability
Get PDFMaackia amurensis lectins serve as research and botanical agents that bind to sialic residues on proteins. For example, M. amurensis seed lectin (MASL) targets the sialic acid modified podoplanin (PDPN) receptor to suppress arthritic chondrocyte inflammation, and inhibit tumor cell growth and motility. However, M. amurensis lectin nomenclature and composition are not clearly defined. Here, we sought to definitively characterize MASL and its effects on tumor cell behavior. We utilized SDS-PAGE and LC-MS/MS to find that M. amurensis lectins can be divided into two groups. MASL is a member of one group which is composed of subunits that form dimers, evidently mediated by a cysteine residue in the carboxy region of the protein. In contrast to MASL, members of the other group do not dimerize under nonreducing conditions. These data also indicate that MASL is composed of 4 isoforms with an identical amino acid sequence, but unique glycosylation sites. We also produced a novel recombinant soluble human PDPN receptor (shPDPN) with 17 threonine residues glycosylated with sialic acid moieties with potential to act as a ligand trap that inhibits OSCC cell growth and motility. In addition, we report here that MASL targets PDPN with very strong binding kinetics in the nanomolar range. Moreover, we confirm that MASL can inhibit the growth and motility of human oral squamous cell carcinoma (OSCC) cells that express the PDPN receptor. Taken together, these data characterize M. amurensis lectins into two major groups based on their intrinsic properties, clarify the composition of MASL and its subunit isoform sequence and glycosylation sites, define sialic acid modifications on the PDPN receptor and its ability to act as a ligand trap, quantitate MASL binding to PDPN with KD in the nanomolar range, and verify the ability of MASL to serve as a potential anticancer agent
Reinforcement Learning for Robotic Tasks: Analyzing and Understanding the Learning Process Using Explainable Artificial Intelligence Methods
Get PDFAs deep reinforcement learning (RL) models gain traction across more industries, there is a growing need for reliable agent-explanation techniques to understand these models. Researchers have developed explainable artificial intelligence (XAI) methods to help understand these \u27black boxes\u27. While these models have been tested on many supervised learning tasks, there is a lack of examination of how these well these methods can explain hard reinforcement learning problems like robotic control. The sequential nature of learning RL policies and testing episodes create fundamentally different policies over time compared to more traditional supervised learning models. In this thesis, two important questions are explored: (1) How well do modern Shapley value based explanation techniques help understand the rationale behind actions made by robotic RL actors? (2) Can these explanations help demystify the RL training loop by estimating the predictive weight of different features throughout training epochs? Through extensive empirical experiments on multiple robotic environments and output analysis, we obtain the following observations: 1. Modern Shapley value explanation techniques often require a significant amount of extra data analysis to comprehend the logic behind trained policies. 2. Important, predictive features are found and ranked highly very early in mid-training epochs before the optimal policy is found
STUDY OF POLYMER-ON-POLYMER COLD SPRAY DEPOSITION WINDOWS UNDER APPARENTLY SIMILAR CONDITIONS
Get PDFThe purpose of this thesis is to explore and expand the capabilities of polymer-on-polymer cold spray demonstrated herein using polyamide 6 (PA6)-based powder and substrates. Experiments were conducted using three different cold spray systems described in this work, permitting more in-depth examination of process response to different cold spray process control parameters, such as nominal system pressure and temperature. Two specific responses of interest were the deposition window (DW) and deposition efficiency (DE) of PA6. The DW was determined by performing several sprays at different calculated particle impact velocities and temperatures. The composite result from these experiments was identification of a large DW in which the role of the particle impact temperature was noticeable enough that, in addition to critical velocity, present results suggest that a critical particle temperature should be considered when determining DWs for polymer powder spraying. Additionally, the combined DW results from all three systems show that particle impact velocity and particle impact temperature alone may be too simple to describe clear regions of deposition. The DE was determined by using a single low-pressure, downstream injection cold spray system. Under favorable conditions, a DE of ∼67% was measured for PA6, roughly seven times higher than the highest DE previously described in the literature for polymer-on-polymer cold spray
Black Men Who Participate in an urban Community College Men of Color Initiative: A phenomenological study
Get PDFThis phenomenological study explored the perceptions and experiences of Black men who participated in the MOCI. The study uncovered insights into what aspects of the program were effective and where improvements could be made according to the student participants. Employing a phenomenological design, the research identified commonalities among the participants\u27 experiences (Creswell & Creswell, 2018; Moustakas, 1994; Rubin & Rubin, 2012). The structure of understanding surrounding participants in the MOCI program was meticulously facilitated using phenomenology (Creswell & Creswell, 2018). The interviews were not just semi-structured but also empathetic, with prepared open-ended questions followed by probing inquiries, all aimed at capturing the essence of the students\u27 experiences (Creswell & Creswell, 2018; Crouch & McKenzie, 2006; Saunders & Townsend, 2016). Three research questions guided the study in elucidating the perceptions and experiences of Black men who participated in the MOCI program. This transcendental phenomenology research aimed to understand how participants described their experiences within the program. The findings revealed that participants consistently expressed a sense of brotherhood, valued program activities and networking opportunities, and felt supported and cared for throughout their involvement