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Diamond-like Carbon (DLC) has been used as a coating material of choice for a variety of technological applications owing to its favorable bio-tribo-thermo-mechanical characteristics. Here, the possibility of bringing DLC into orthopedic joint implants is examined. With ever increasing number of patients suffering from osteoarthritis as well as with the ingress of the osteoarthritic joints malaise into younger and more active demographics, there is a pressing need to augment the performance and integrity of conventional total joint replacements (TJRs). Contemporary joint replacement devices use metal-on-polymer articulations to restore function to worn, damaged or diseased cartilage. The wear of polymeric components has been addressed using crosslinking and antioxidants; however, in the context of the metallic components, complications pertaining to corrosion and metal ion release inside the body still persist. Through this review article, we explore the use of DLC coatings on metallic bearing surfaces and elucidate why this technology might be a viable solution for ongoing electrochemical challenges in orthopedics. The different characteristics of DLC coatings and their feasibility in TJRs are examined through assessment of tribo-material characterization methods. A holistic characterization of the coating-substrate interface and the wear performance of such systems are discussed. As with all biomaterials used in TJRs, we need mindful consideration of potential in-vivo challenges. We present a few caveats for DLC coatings including delamination, hydrophobicity, and other conflicting as well as outdating findings in the literature. We recommend prudently exploring DLC films as potential coatings on metallic TJR components to solve the problems pertaining to wear, metal ion release, and corrosion. Ultimately, we advise bringing DLC into clinical use only after addressing all challenges and concerns outlined in this article.

Poly-ether-ether-ketone (PEEK) and PEEK composites are outstanding candidates for biomedical applications, such as orthopedic devices, where biocompatibility and modulus match with surrounding tissue are requisite for long-term success. The mechanical properties can be optimized by incorporating fillers such as continuous and chopped carbon fibers. While much is known about the mechanical and tribological behavior of PEEK composites, there are few articles that summarize the viability of using PEEK reinforced with carbon fibers in orthopedic implants. This paper reviews biocompatibility, tribological, and mechanical studies on PEEK and their composites with carbon fibers, notably PEEK reinforced with polyacrylonitrile (PAN)-based carbon fibers and PEEK reinforced with pitch-based carbon fibers, for application in orthopedics and total joint replacements (TJRs). The main objectives of this review are two-fold. Firstly, this paper aims to assist designers in making informed decisions on the suitability of using PEEK and PEEK composites in orthopedic applications; as it is not well understood how these materials perform on the whole in orthopedics and TJRs. Secondly, this paper aims to serve as a centralized paper in which researchers can gain information on the tribological and mechanical advancements of PEEK and PEEK composites.

California’s housing crisis stems from an inadequate supply of affordable housing coupled with insufficient legal protections for renters and homeowners. The resulting access-to-justice challenge for low-income and modest-means residents is aggravated in rural areas by the underfunding of legal-aid organizations and the state’s rural lawyer shortage. All of these factors contribute to recent increases in the state’s homeless population. Free, high-quality Legal Aid is needed urgently. We recommend the passing of new laws that protect rural low-income renters and homeowners. We also suggest that policymakers act to fund Legal Aid robustly, in a geographically equitable fashion, in order to support legal services organizations in rural areas.

Distance—physical, material distance—is an obviously spatial concept, but one rarely engaged by legal or feminist geographers. We take up this oversight in relation to the 2016 U.S. Supreme Court decision in Whole Woman’s Health v. Hellerstedt, which adjudicated the constitutionality of a Texas law that imposed new regulations on abortion providers. Because half of the state’s abortion providers were unable to meet these regulations and thus closed, the distance that many Texas women had to travel for abortion services increased dramatically. In part because of these increases, the Supreme Court ultimately determined that the Texas laws imposed an unconstitutional “undue burden.” Bringing together case law and ethnographic data, this article traces the process by which distance is made legally “legible” in the context of reproductive injustice. In so doing, it confronts more uneasy realities of distance, including the discursive dismissal of social and literal immobility and isolation; contradictory readings of “emptiness”; and the material spatiality of distance through the nonplace-ness of rural areas. Together, these factors illuminate a more significant distance, namely the epistemic and social distance that exists between the legal performance of distance in litigation and the embodied traversal of distance by a woman seeking an abortion in Texas. Prioritizing rural distance as material, legal and gendered, our work engages and augments the nascent field of feminist legal geographies. It likewise challenges legal geographers’ insistence on urban space by uncovering the ways in which even the relative “emptiness” of distance is intimately consequential. Finally, this paper makes connections between the exercise of the abortion right and the exercise of other rights that implicate distance, most notably the right to vote. Just as abortion regulations have often had the effect of requiring women to travel farther for abortion services, voter ID laws have the effect of requiring voters to travel to a public agency in order to secure the requisite identity document. Other voting regulations and state and local voting practices may similarly impose spatial burdens on voters. We thus assert that what Whole Woman’s Health reveals about making distance legally cognizable finds ready legal application in other contexts.

A cemented, cast CoCr alloy, Omnifit Plus femoral stem was retrieved following mid-stem fracture after 24 years in vivo. The patient was an active 55-year-old male with a high body mass index (31.3) and no traumatic incidents before stem fracture. Fractographic and fatigue-based failure analyses were performed to illuminate the etiology of fracture and retrospectively predict the device lifetime. The fracture surfaces show evidence of a coarse grain microstructure, intergranular fracture, and regions of porosity. The failure analysis suggests that stems with similar metallurgical characteristics, biomechanical environments, and in vivo durations may be abutting their functioning lifetimes, raising the possibility of an increased revision burden.

This article examines the challenges of addressing spatial inequalities and uneven development in the United States, specifically in rural and nonmetropolitan areas that have been left behind. It discusses the political obstacles and negative perceptions that hinder efforts to help these places. The article analyzes the approaches of former Presidents Obama and Trump towards these issues, emphasizing the need for investment and support in left-behind areas. It also explores the divide between rural and urban communities, the resentment felt by the rural population towards urban areas, and the role of media and racial attitudes in deepening this divide. The text suggests that investments in rural America, along with respectful engagement and empathy, are necessary to bridge this gap and strengthen democracy. [Extracted from the article]

The predominant cause of late-state failure of total hip replacements is wear-mediated osteolysis caused by wear particles that originate from the ultrahigh molecular weight polyethylene (UHMWPE) acetabular cup surface. One strategy for reducing wear particle formation from UHMWPE is to modify the surface with a hydrophilic coating to increase lubrication from synovial fluid. This study focuses on the wear behavior of hydrophilic coatings similar to poly(ethylene glycol) (PEG). The coatings were produced by plasma-polymerizing tetraglyme on UHMWPE in a chamber heated to 40°C or 50°C. Both temperatures yielded coatings with PEG-like chemistry and increased hydrophilicity relative to uncoated UHMWPE; however, the 40°C coatings were significantly more resistant to damage induced by atomic force microscopy nanoscratching. The 40°C coatings exhibited only one damage mode (delamination) and often showed no signs of damage after repeated scratching. In contrast, the 50°C coatings exhibited three damage modes (roughening, thinning, and delamination), and always showed visible signs of damage after no more than two scratches. The greater wear resistance of the 40°C coatings could not be explained by coating chemistry or hydrophilicity, but it corresponded to an approximately 26–32% greater degree of crosslinking relative to the 50°C surfaces, suggesting that crosslinking should be a significant design consideration for hydrophilic coatings used for total hip replacements and other wear-dependent applications.

This Article addresses how law schools can better support first-generation ("first-gen") students, typically defined as those for whom neither parent has a bachelor's degree. We survey first-gen programming in U.S. law schools, the broad goal of which is to retain students and help them to thrive, thereby increasing their educational and career achievement. We link this goal to extensive research on the growing challenge of upward mobility. In addition, we synthesize the vast empirical research about first-gen students, most of it about undergraduates, with a view to identifying beneficial interventions. We also summarize what quantitative data, collected by the Law School Survey of Student Engagement (LSSSE) and the National Association of Law Placement (NALP), reveal about the first-gen student population. The first-gen project has been made more salient by the Supreme Court's 2023 ruling in Students for Fair Admissions vs. Harvard, which held unconstitutional the use of race as a basis for affirmative action in higher education admissions. The first-gen category provides an alternative basis for assisting many students of color, while also supporting socioeconomically disadvantaged white students. Indeed, these programs may foster cross-racial collaboration and coalition building as students from a wide range of races and ethnicities gain an appreciation for the shared struggle for upward mobility they face. Importantly, these students may carry an orientation to see common ground beyond the educational setting and into the wider world, thus helping bridge the growing cultural and ideological divides polarizing our nation. Lastly, we offer insights from a seminar Pruitt teaches at UC Davis. The course, created for first-gen students, draws on scholarly literature, memoir, and fiction to explore the first-gen experience. The seminar is an invitation for students to tell their own first-gen stories, drawing on those narratives as sources of empowerment. We reveal some of the challenges, pitfalls, and successes of this course, and we discuss other curricular offerings that could foster a sense of belonging--and success--for first-gen law students. Ultimately, we call for more empirical research into the experiences of first-gen students in U.S. law schools. [ABSTRACT FROM AUTHOR]