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Qualifying exams and thesis committees are crucial components of a PhD candidate's journey. However, many candidates have trouble navigating these milestones and knowing what to expect. This article provides advice on meeting the requirements of the qualifying exam, understanding its format and components, choosing effective preparation strategies, retaking the qualifying exam, if necessary, and selecting a thesis committee, all while maintaining one's mental health. This comprehensive guide addresses components of the graduate school process that are often neglected.

A first‐generation college student is typically defined as a student whose biological parent(s) or guardian(s) never attended college or who started but did not finish college. However, “first‐generation” can represent diverse family education situations. The first‐generation student community is a multifaceted, and intersectional group of individuals who frequently lack educational/financial resources to succeed and, consequently, require supportive environments with rigorous mentorship. However, first‐generation students often do not make their identity as first‐generation students known to others due to several psychosocial and academic factors. Therefore, they are often “invisible minorities” in higher education. In this paper, we describe the diverse family situations of first‐generation students, further define “first‐generation,” and suggest five actions that first‐generation trainees at the undergraduate/graduate stages can engage in to succeed in an academic climate. We also provide suggestions for mentors to accommodate first‐generation students' unique experiences and equip them with tools to deliver intentional mentoring practices. We hope that this paper will help promote first‐generation student success throughout the academic pipeline.

Mitochondria are required for energy production and even give brown adipose tissue (BAT) its characteristic color due to their high iron content and abundance. The physiological function and bioenergetic capacity of mitochondria are connected to the structure, folding, and organization of its inner‐membrane cristae. During the aging process, mitochondrial dysfunction is observed, and the regulatory balance of mitochondrial dynamics is often disrupted, leading to increased mitochondrial fragmentation in aging cells. Therefore, it is hypothesized that significant morphological changes in BAT mitochondria and cristae will be present with aging. A quantitative 3D electron microscopy approach is developed to map cristae network organization in mouse BAT to test this hypothesis. Using this methodology, the 3D morphology of mitochondrial cristae is investigated in adult (3‐month) and aged (2‐year) murine BAT tissue via serial block face‐scanning electron microscopy (SBF‐SEM) and 3D reconstruction software for manual segmentation, analysis, and quantification. Upon investigation, an increase is found in mitochondrial volume, surface area, and complexity and decreased sphericity in aged BAT, alongside significant decreases in cristae volume, area, perimeter, and score. Overall, these data define the nature of the mitochondrial structure in murine BAT across aging.

During aging, muscle gradually undergoes sarcopenia, the loss of function associated with loss of mass, strength, endurance, and oxidative capacity. However, the 3D structural alterations of mitochondria associated with aging in skeletal muscle and cardiac tissues are not well described. Although mitochondrial aging is associated with decreased mitochondrial capacity, the genes responsible for the morphological changes in mitochondria during aging are poorly characterized. We measured changes in mitochondrial morphology in aged murine gastrocnemius, soleus, and cardiac tissues using serial block‐face scanning electron microscopy and 3D reconstructions. We also used reverse transcriptase‐quantitative PCR, transmission electron microscopy quantification, Seahorse analysis, and metabolomics and lipidomics to measure changes in mitochondrial morphology and function after loss of mitochondria contact site and cristae organizing system (MICOS) complex genes,Chchd3,Chchd6, andMitofilin. We identified significant changes in mitochondrial size in aged murine gastrocnemius, soleus, and cardiac tissues. We found that both age‐related loss of the MICOS complex and knockouts of MICOS genes in mice altered mitochondrial morphology. Given the critical role of mitochondria in maintaining cellular metabolism, we characterized the metabolomes and lipidomes of young and aged mouse tissues, which showed profound alterations consistent with changes in membrane integrity, supporting our observations of age‐related changes in muscle tissues. We found a relationship between changes in the MICOS complex and aging. Thus, it is important to understand the mechanisms that underlie the tissue‐dependent 3D mitochondrial phenotypic changes that occur in aging and the evolutionary conservation of these mechanisms betweenDrosophilaand mammals.

Various intracellular degradation organelles, including autophagosomes, lysosomes, and endosomes, work in tandem to perform autophagy, which is crucial for cellular homeostasis. Altered autophagy contributes to the pathophysiology of various diseases, including cancers and metabolic diseases. This paper aims to describe an approach to reproducibly identify and distinguish subcellular structures involved in macroautophagy. Methods are provided that help avoid common pitfalls. How to distinguish between lysosomes, lipid droplets, autolysosomes, autophagosomes, and inclusion bodies are also discussed. These methods use transmission electron microscopy (TEM), which is able to generate nanometer‐scale micrographs of cellular degradation components in a fixed sample. Serial block face‐scanning electron microscopy is also used to visualize the 3D morphology of degradation machinery using the Amira software. In addition to TEM and 3D reconstruction, other imaging techniques are discussed, such as immunofluorescence and immunogold labeling, which can be used to classify cellular organelles, reliably and accurately. Results show how these methods may be used to accurately quantify cellular degradation machinery under various conditions, such as treatment with the endoplasmic reticulum stressor thapsigargin or ablation of the dynamin‐related protein 1.

Single crystal scintillators have become one of the most common materials used in technologies that use radiation detectors. Unfortunately, as technology demands improved detectors, research into better single crystal scintillators has nearly reached its limit. Ceramics provide many benefits over single crystal scintillators and have emerged as a promising new production process. Recent research into ceramic scintillators has mostly dealt with oxides as they are relatively easy to handle and are typically non‐hygroscopic. Among single crystal scintillators, a trend has emerged indicating that the addition of halide ions into the crystal structure improves the light yield and energy resolution of the scintillation material but also tends to make the material hygroscopic and in some cases intrinsically radioactive. Little research is devoted to the investigation of undoped halide ceramic scintillators. Transparent halide Cs₂HfCl₆ceramics are developed by hot uniaxial pressing, and the scintillation properties are compared to that of its single crystal counterpart. The energy resolution of the ceramic is found to be 6.4% at 662 keV. The initial results indicate that ceramic scintillators are a viable alternative and a promising new direction in scintillator material technology.

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Mitochondrial transplantation has been used to treat various diseases associated with mitochondrial dysfunction. Here, we highlight the considerations in quality control mechanisms that should be considered in the context of mitochondrial transplantation.

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This perspective considers several avenues for future research on mitochondrial dynamics, stress, and DNA in outer space.