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In theorizing how we should pedagogically approach African American literature, especially in courses for undergraduates, I argue that we have to move away from questions of what was or even what is African American literature and, instead, find ways to teach African American literature in both its historical contexts--artistic and political--and its contemporary resonances. We can embrace the ways the field and each piece of literature simultaneously was and is. Importantly, we can think about what both African American literature and the course on this literature need to be in ways that focus on past, present, and future. For students, African American literature can be a living voice in a broader trajectory of civil and social death, de jure and de facto discrimination, and the struggle for social justice. Our current moment demands it, and the persistence of the Black Lives Matter movement--from its origins in the wake of Trayvon Martin and Michael Brown's deaths into the early stages of the 2016 U.S. presidential campaigns' warrants, or perhaps even necessitates, a pedagogy that positions African American literature courses as spaces on campuses where the vulnerabilities of and violent acts against black lives can be discussed. In this paper, I am particularly interested in examining both the praxis of teaching African American literature as part of a cultural and civic literacy program for our students and then in examining the larger stakes of our moment, both for racism in the United States and the role of literature courses of programs.

Local and superficial optical property characterization of biological tissues can be performed by measuring spatially-resolved diffuse reflectance at small source-detector separations. Monte Carlo simulations and experiments were performed to assess the performance of a spatially-resolved reflectance probe, employing multiple detector fibers (0.3 to 1.4 mm from the source). Under these conditions, the inverse problem, i.e. calculating the absorption and reduced scattering coefficients, is necessarily sensitive to the phase function. This effect must be taken into account by considering a new parameter of the phase function, which depends on the first and second moments of the phase function. Probe performance is compared to another technique for quantitatively measuring optical coefficients, based on the analysis of photon density waves (Frequency Domain Photon Migration). The two techniques are found to be in reasonable agreement. However, the spatially resolved probe shows optimum measurement sensitivity in the volume immediately beneath the probe, while FDPM typically samples much larger regions of tissues. Measurements on human brain in vivo are reported using both methods.

Targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI) are used to prevent or treat neuromas in amputees. TMR for above-the-knee amputation (AKA) is most commonly performed through a posterior incision rather than the stump wound because recipient motor nerves are primarily located in the proximal third of the thigh. When preventative TMR is performed with concurrent AKA, a posterior approach requires intraoperative repositioning and an additional incision. The purpose of this study was to evaluate feasibility of TMR and operative times for nerve management performed through the wound compared to a posterior approach in AKA patients to guide surgical decision-making. Patients who underwent AKA with TMR between 2018–2023 were reviewed. Patients were divided into two groups: TMR performed through the wound (Group I) and TMR performed through a posterior approach (Group II). If a nerve was unable to undergo coaptation for TMR due to the lack of suitable donor motor nerves, RPNI was performed. Eighteen patients underwent AKA with nerve management were included from Group I (8 patients) and Group II (10 patients). TMR coaptations performed on distinct nerves was 1.5 ± 0.5 in Group I compared to 2.6 ± 0.5 in Group II (p = 0.001). Operative time for Group I was 200.7 ± 33.4 min compared to 326.5 ± 37.1 min in Group II (p = 0.001). TMR performed through the wound following AKA requires less operative time than a posterior approach. However, since recipient motor nerves are not consistently found near the stump, RPNI may be required with TMR whereas the posterior approach allows for more TMR coaptations. [ABSTRACT FROM AUTHOR]

Local and superficial optical characterization of biological tissues can be achieved by measuring the spatially resolved diffuse reflectance at small source-detector separations. The sensitivity of the signal to the phase function, absorption and scattering coefficients were studied using Monte Carlo simulations. Measurements of spatially resolved reflectance were performed in vivo on human brain with source-detector separations from 0.3 to 1.5 mm. Distinct optical properties were found between normal cortex, astrocytoma of optic nerve and normal optic nerve.

A multiwavelength, high bandwidth (1 GHz) frequency-domain photon migration (FDPM) instrument has been developed for quantitative, non-invasive measurements of tissue optical and physiological properties. The instrument produces 300 kHz to 1 GHz photon density waves (PDWs) in optically turbid media using a network analyser, an avalanche photodiode detector and four amplitude-modulated diode lasers (674 nm, 811 nm, 849 nm, and 956 nm). The frequency of PDW phase and amplitude is measured and compared to analytically derived model functions in order to calculate absorption, mu a, and reduced scattering, mu s, parameters. The wavelength-dependence of absorption is used to determine tissue haemoglobin concentration (total, oxy- and deoxy- forms), oxygen saturation and water concentration. We present preliminary results of non-invasive FDPM measurements obtained from normal and tumour-containing human breast tissue. Our data clearly demonstrate that physiological changes caused by the presence of small (about 1 cm diameter) palpable lesions can be detected using a handheld FDPM probe.

Skin and cellular aging are impacted by various toxins in our environment such as air pollution, water contamination, an increased prevalence of light-emitting diodes, electromagnetic frequencies, various yeast and other fungi, parasitic infections, and mold and heavy metal toxicity. Basic topical skin care is insufficient to adequately protect an individual’s integumentary system and other organs from these types of daily cellular stressors. These stressors impact the level of oxidative stress status (OSS). OSS is measurable through biomarker analysis of various body fluids including blood, saliva, urine, and breath. This poses a unique assessment challenge for aesthetic practitioners as the OSS of a patient impacts their overall aging process. Aesthetic practitioners observe the aging process through visual assessment of a patient’s skin quality, skin barrier function, and the presence of solar lentigines, erythema, edema, telangiectasia, loss of collagen and elastin, bone density, and redistribution of subcutaneous tissue. Mitigating a patient’s daily exposure to OS and its impacts on the skin, other organ tissues, and metabolism poses a unique challenge in medical aesthetic treatment planning. For this reason, the use of stem cells and exosomes is gaining popularity in aesthetic medicine. The purpose of this literature review is to highlight currently available research, applications, limitations, and mitigation strategies in reducing OSS on the integumentary system and aging processes. [ABSTRACT FROM AUTHOR]

Background: Since the COVID-19 pandemic of 2020, there has been a marked rise in the use of telemedicine to evaluate patients after total knee arthroplasty (TKA). The purpose of our study was to assess a novel stem with an embedded sensor that can remotely and objectively monitor a patient's mobility after TKA.Methods: A single anatomically designed knee system was implanted in concert with an interconnected tibial stem extension containing 3D accelerometers, 3D gyroscopes, a power source, and a telemetry transmission capability in 3 cadaveric pelvis to toe specimens. The legs were moved by hand to preset tibial positions at full knee extension, midflexion, flexion, and back to midflexion and extension for a total of 16 trials across 6 knees.Results: Sensor data were successfully transmitted with good quality of signal to an external base station. Good correlation to the range of motion of the tibia was found (mean error 0.1 degrees; root mean square error 3.8 degrees). The signal from the heel drop tests suggests the sensor could detect heel strike during activities of daily living in vivo and the potential for additional signal processing to analyze vibratory and motion patterns detected by the sensors. A frequency domain analysis of a properly cemented and poorly cemented implant during the heel drop test suggests a difference in accelerometer signal in these implant states.Conclusion: The results confirm signals generated from an embedded TKA sensor can transmit through bone and cement, providing accurate range of motion data and may be capable of detecting changes in prosthesis fixation remotely. [ABSTRACT FROM AUTHOR]

Purpose: To report patients who demonstrated an alteration in the clinical and optical coherence tomography features of neovascular age-related macular degeneration after resolution of endophthalmitis. Methods: Retrospective case series of the subsequent changes in the macula and need for anti-vascular endothelial growth factor therapy in patients with neovascular age-related macular degeneration who developed endophthalmitis after intravitreal injection. Results: The study included seven eyes of seven patients with follow-up ranging between 3 months and 11 years. The vitreous cultures (n = 7) before intravitreal antibiotic injection were the following: culture-negative (4) and coagulase-negative Staphylococcus (3). Initial treatment included vitreous tap and injection (4) and pars plana vitrectomy (3). In 5/7 eyes, the optical coherence tomography showed resolution of subretinal fluid and serous pigment epithelial detachment, and there was no additional anti-vascular endothelial growth factor treatment administered. Conclusion: After successful treatment of endophthalmitis in patients with neovascular age-related macular degeneration, there was relative involution of the maculopathy and reduced anti-vascular endothelial growth factor treatment burden in this series. [ABSTRACT FROM AUTHOR]

Background: Numerous gaseous microemboli (GME) are delivered into the arterial circulation during cardiopulmonary bypass (CPB). These emboli damage end organs through multiple mechanisms that are thought to contribute to neurocognitive deficits after cardiac surgery. Here, we use hypobaric oxygenation to reduce dissolved gases in blood and greatly reduce GME delivery during CPB. Methods: Variable subatmospheric pressures were applied to 100% oxygen sweep gas in standard hollow fiber microporous membrane oxygenators to oxygenate and denitrogenate blood. GME were quantified using ultrasound while air embolism from the surgical field was simulated experimentally. We assessed end-organ tissues in swine postoperatively using light microscopy. Results: Variable sweep gas pressures allowed reliable oxygenation independent of carbon dioxide removal while denitrogenating arterial blood. Hypobaric oxygenation produced dose-dependent reductions of Doppler signals produced by bolus and continuous GME loads in vitro. Swine were maintained using hypobaric oxygenation for 4 hours on CPB with no apparent adverse events. Compared with current practice standards of oxygen/air sweep gas, hypobaric oxygenation reduced GME volumes exiting the oxygenator (by 80%), exiting the arterial filter (95%), and arriving at the aortic cannula (∼100%), indicating progressive reabsorption of emboli throughout the CPB circuit in vivo. Analysis of brain tissue suggested decreased microvascular injury under hypobaric conditions. Conclusions: Hypobaric oxygenation is an effective, low-cost, common sense approach that capitalizes on the simple physical makeup of GME to achieve their near-total elimination during CPB. This technique holds great potential for limiting end-organ damage and improving outcomes in a variety of patients undergoing extracorporeal circulation. [Copyright &y& Elsevier]