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In this paper, the study of nonsmooth optimal control problems (P) involving a controlled sweeping process with three main characteristics is launched. First, the sweeping sets C(t) are nonsmooth, unbounded, time-dependent, uniformly prox-regular, and satisfy minimal assumptions. Second, the sweeping process is coupled with a controlled differential equation. Third, joint-state endpoints constraint set S, including periodic conditions, is present. The existence and uniqueness of a Lipschitz solution for our dynamic is established, the existence of an optimal solution for our general form of optimal control is obtained, and the full form of the nonsmooth Pontryagin maximum principle for strong local minimizers in (P) is derived under minimal hypotheses. One of the novelties of this paper is the idea to work with a well-constructed problem corresponding to truncated sweeping sets and joint endpoint constraints that shares the same strong local minimizer as (P) and for which the exponential-penalty approximation technique can be developed using only the assumptions on (P).

The numerical method developed in [30] for optimal control problems involving sweeping processes with smooth sweeping set C is generalized to the case where C is nonsmooth, namely, C is the intersection of a finite number of sublevel sets of smooth functions. The novelty of this extension resides in producing for the general setting a different approach, since the one used for the smooth sweeping sets is not applicable here.

We extend to $\mathrm{C}\times \mathrm{W}^{1,2}$-local minimizers and nonautonomous perturbation function, the necessary optimality conditions derived in [1], via continuous-time approximations, for $\mathrm{W}^{1,2}\times \mathrm{W}^{1,2}$-local minimizers of an optimal control problem governed by a controlled nonconvex sweeping process with autonomous perturbation function., Comment: arXiv admin note: text overlap with arXiv:2301.00475

This survey article provides insights regarding the future of affirmative action by analyzing the implementation methods and the empirical evidence on the use of placement quotas in the Brazilian higher education system. All federal universities have required income and racial-based quotas in Brazil since 2012. Affirmative action in federal universities is uniformly applied across the country, which makes evaluating its effects particularly valuable. Affirmative action improves the outcomes of targeted students. Specifically, race-based quotas raise the share of black students in federal universities, an effect not observed with income-based quotas alone. Affirmative action has downstream positive consequences for labor market outcomes. The results suggest that income and race-based quotas beneficiaries experience substantial long-term welfare benefits. There is no evidence of mismatching or negative consequences for targeted students' peers.

The Pontryagin-type maximum principle derived in [30] for optimal control problems involving sweeping processes is generalized to the case where the sweeping set C is nonsmooth and not necessarily bounded, namely, C is the intersection of a finite number of zero-sublevel sets of smooth functions.

A controlled sweeping process with prox-regular set, $W^{1,2}$-controls, and separable endpoints constraints is considered in this paper. Existence of optimal solutions is established and local optimality conditions are derived via strong converging continuous approximations that entirely reside in the interior of the prox-regular set. Consequently, these results are expressed in terms of new subdifferentials for the original data that are strictly smaller than the standard Clarke and Mordukhovich subdifferentials.

Fetal growth restriction (FGR) is a prevalent pregnancy condition characterised by failure of the fetus to reach its genetically predetermined growth potential. We explore the application of model fitting techniques, linear regression machine learning models, deep learning regression, and Haralick textured features from multi-contrast MRI for multi-fetal organ analysis of FGR. We employed T2 relaxometry and diffusion-weighted MRI datasets (using a combined T2-diffusion scan) for 12 normally grown and 12 FGR gestational age (GA) matched pregnancies. We applied the Intravoxel Incoherent Motion Model and novel multi-compartment models for MRI fetal analysis, which exhibit potential to provide a multi-organ FGR assessment, overcoming the limitations of empirical indicators - such as abnormal artery Doppler findings - to evaluate placental dysfunction. The placenta and fetal liver presented key differentiators between FGR and normal controls (decreased perfusion, abnormal fetal blood motion and reduced fetal blood oxygenation. This may be associated with the preferential shunting of the fetal blood towards the fetal brain. These features were further explored to determine their role in assessing FGR severity, by employing simple machine learning models to predict FGR diagnosis (100\% accuracy in test data, n=5), GA at delivery, time from MRI scan to delivery, and baby weight. Moreover, we explored the use of deep learning to regress the latter three variables. Image texture analysis of the fetal organs demonstrated prominent textural variations in the placental perfusion fractions maps between the groups (p$<$0.0009), and spatial differences in the incoherent fetal capillary blood motion in the liver (p$<$0.009). This research serves as a proof-of-concept, investigating the effect of FGR on fetal organs.

Radiation therapy is an effective and widely accepted form of treatment for many types of cancer that requires extensive computerized planning. Unfortunately, current treatment planning systems have limited or no visual aid that combines patient volumetric models extracted from patient-specific CT data with the treatment device geometry in a 3D interactive simulation. We illustrate the potential of 3D simulation in radiation therapy with a web-based interactive system that combines novel standards and technologies. We discuss related research efforts in this area and present in detail several components of the simulator. An objective assessment of the accuracy of the simulator and a usability study prove the potential of such a system for simulation and training.

As humankind endeavors to travel farther away from Earth, many questions remain to be solved to ensure proper preparation for deep space. Multiple spaceflight stressors can elicit adverse health outcomes including exposure to space radiation. Space radiation exposure has been identified by the National Aeronautics and Space Administration (NASA) as an important contributor to cancer, degenerative tissue diseases including cataracts, cardiovascular disease, immune system dysfunction and possible central nervous system decrements. The complexity of the human central nervous system makes it difficult to adequately recapitulate in experimental model systems, which hinders quantitative description of associated decrements. The brain aging hallmarks, as introduced by Mattson and Arumugam in 2018, are measurable cellular and molecular hallmarks that generally contribute to the aging process, describe an aging phenotype, and are part of the etiology of age-related neurodegenerative diseases. These hallmarks include mitochondrial dysfunction, accumulation of oxidatively damaged molecules (oxidative stress), impaired lysosome and proteasome function, dysregulation of neuronal calcium homeostasis, compromised adaptive cellular stress response, aberrant neuronal network activity, impaired deoxyribonucleic acid (DNA) repair, inflammation, impaired neurogenesis and dysregulated energy metabolism. Cellular senescence and telomere attrition may also be considered, though more evidence is needed to regard them as brain-specific hallmarks of aging. Radiation exposure has previously been correlated with aging etiology; therefore, investigating the effects of radiation exposure within the context of the hallmarks of brain aging may provide insights into potential health risks facing NASA astronauts, and may provide a means to identify disease processes that may be important targets for disease prevention or intervention. This work describes the hallmarks of brain aging and serves as a primer for future investigation into how the hallmarks of brain aging may compare and contrast with outcomes associated with exposure to the space radiation environment. Further, it will be useful in future identification of hallmarks that may be appropriate to target for radiation countermeasures specific to the central nervous system.

In this paper, locally Lipschitz functions acting between infinite dimensional normed spaces are considered. When the range is a dual space and satisfies the Radon--Nikod\'ym property, Clarke's generalized Jacobian will be extended to this setting. Characterization and fundamental properties of the extended generalized Jacobian are established including the nonemptiness, the $\beta$-compactness, the $\beta$-upper semicontinuity, and a mean-value theorem. A connection with known notions is provided and chain rules are proved using key results developed. This included the vectorization and restriction theorem, and the extension theorem. Therefore, the generalized Jacobian introduced in this paper is proved to enjoy all the properties required of a derivative like-set.

High speed motion pictures have revealed several operating regimes in a squeeze film damper. Pressure measurements corresponding to these distinct regimes were made to examine their effect on the performance of such dampers. Visual observation also revealed the means by which the pressure in the feed groove showed higher amplitudes than the theory predicts. Comparison between vapor and gaseous cavitation are made based on their characteristic pressure wave, and the effect this has on the total force and its phase.

A vibration instability phenomenon experienced in operating high pressure syn gas centrifugal compressors in two ammonia plants is described. The compressors were monitored by orbit and spectrum analysis for changes from baseline readings. It is found that internal hysteresis was the major destabilizing force; however, the problem was further complicated by seal lockup at the suction end of the compressor. A coupling lockup problem and a coupling fit problem, which frettage of the shaft, are also considered as contributors to the self excited vibrations.