Research on the use of health care systems has always had two fundamental rationales. First, and most directly, the continued high levels of unmet need, especially for mental health problems and for individuals from minoritized populations, raise concerns both about equity in care and levels of population health. Second, and more generally, understanding how individuals respond to the onset of crises, how they do or do not make decisions, whether they do or do not end up receiving treatment, can find no more critical example than when life and death are at stake. From the earliest studies that countered an ideal view of the “illness career” to recent complex systems models, a range of theories from social science and public health have offered guidance to understanding and examining health care utilization. Here, we describe a pioneering early approach and its critics followed by an overview and findings from the most dominant theoretical models that have been deployed. We describe recent trends that challenge the usual approach and offer three more recent models that target social networks generally and/or health care disparities specifically. We end with a discussion that provides both a sense of where we are and suggests new questions raised by contemporary changes in the landscape of care. Readers should consider how different disciplines and models conceptualized how, why and which people with mental health problems receive care in the formal health system. Further, what do recent studies add to our understanding of the social factors associated with the receipt of treatment and the patterns and pathway by which individuals get there?

Following directly the from the previous chapter, we see that in addition to a shift toward shorter peak wavelength, a higher temperature also increases the overall brightness of blackbody emission at all wavelengths. This suggests that the total energy emitted over all wavelengths should increase quite sharply with temperature. We introduce the Stefan-Boltzmann law, one of the linchpins of stellar astronomy.

How mental distress is understood and defined has significant social and political implications. For this reason, psychiatric nosology – the classification of mental disorders – has come to occupy a central role in debates over mental health policy, patient identity politics, and the professional authority of psychiatry. This chapter explores sociological research on psychiatric nosology. The first section examines the history of classification of mental disorders in the United States, focusing on the professional dynamics that have shaped the Diagnostic and Statistical Manual of Mental Disorders (DSM). The second section describes three key areas of sociological research on psychiatric nosology – medicalization, diagnostic practice, and patient identity – that highlight how social and political factors influence the classification of mental disorders and the concomitant effects of psychiatric nosology. In terms of discussion, how has medicalization impacted our understanding and classification of mental health disorders? Which diagnoses and disorders will later be recognized as acceptable diversity, as was the case with homosexuality? How do social and political factors affect the categorization of mental disorders? Specifically, how has the production, use, and reception of the DSM been shaped by “extra-scientific” political (professional or otherwise) considerations?

Societal concern regarding mental health and illness has grown exponentially worldwide since the publication of the last volume, A Handbook for the Study of Mental Health: Social Contexts, Theories, and Systems (2017). Over the past decade, public policymakers, researchers, clinicians, people living with mental health challenges, those who love them, and journalists in the United States and around the world have spoken out, more frequently and forcefully, about rates of mental distress and the need for policy reforms to increase access and strengthen mental health care. The chapters in this book highlight many of the most important contributions and insights that sociologists of mental health have made to these crucial public conversations as well as to contemporary scientific advancements in the understanding and treatment of mental health and illness.

Mass is clearly a physically important parameter for a star, as it will determine the strength of the gravity that tries to pull the star’s matter together. We discuss one basic way we can determine mass, from orbits of stars in stellar binaries, and see the range of stellar masses. This leads us to the virial theorem, which describes a stably bound gravitational system.

We conclude our discussion of stellar properties by considering ways to infer the rotation of stars. All stars rotate, but in cool, low-mass stars like the Sun the rotation is quite slow. In hotter, more-massive stars, the rotation can be more rapid, with some cases (e.g., the Berillium stars) near the "critical" rotation speed at the star’s surface.

This chapter considers stellar ages. Just how old are stars like the Sun? What provides the energy that keeps them shining? And what will happen to them as they exhaust various available energy sources? We show that the ages and lifetimes of stars like the Sun are set by long nuclear burning timescales and the implications that high-mass stars should have much shorter lifetimes than low-mass stars.

Social relationships are crucial to healthy human development. We first learn to relate to others as young children, and the ways in which we learn to attach and relate to others have life-long consequences. In this chapter, we further explore our understanding of social bonds as a key aspect of human development and provide an overview of the different ways that sociologists define social relationships. Then, we discuss the relationship between social support and mental health and consider ways that it is influenced by social statuses such as socioeconomic status, race and ethnicity, and gender identity. As you read, we encourage you to consider these questions: Can you differentiate the perceived from the structural aspects of your relationships? Why do you suppose that the perception of social support matters more than “actual” support received in predicting psychological well-being? Can you give an example of a main effect of social support you have experienced, as well as a buffering effect?

The timescale analyses in Chapter 8 show that nuclear fusion provides a long-lasting energy source that we can associate with main sequence stars in the H-R diagram. This chapter addresses the following questions: What are the requirements for H to He fusion to occur in the stellar core? And how is this to be related to the luminosity vs. surface temperature scaling for main sequence stars? In particular, how might this determine the relation between mass and radius? What does it imply about the lower mass limit for stars to undergo hydrogen fusion?

Much as stars within galaxies tend to form within stellar clusters, the galaxies in the universe also tend to collect in groups, clusters, or even in a greater hierarchy of clusters of clusters, known as "super-clusters." Plots of galaxy positions versus redshift distance reveal the large-scale structure of the universe as a "cosmic web," with galaxies lying along extended, thin "walls" and densely clustered intersections, surrounded by huge voids with few or no galaxies in between.

In this chapter we examine the relationship between mental health and terrorism in the social science literature. We expand the study of terrorism to areas such as domestic terrorism and other forms of hate-motivated violence. Both broad theoretical advances and focused conceptual refinements are identified and discussed. There has been a dramatic increase in research focusing on the topics of terrorisms and mental health in the years after the four coordinated September 11 attacks in the United States. Since then, a focus on other forms of hate-motivated intergroup violence has emerged and continues to slowly grow, encompassing domestic terrorism (in various forms) and its impact on others in targeted groups (ethnic, racial, religious, or ideological), across generations, (legacy and historical trauma) or within their communities (community trauma). There has also been a growing focus on positive outcomes, especially resilience. Many of the questions raised by the research remain unanswered. Do the effects of trauma that occurred during the peak in terrorism persist among its victims? Will the emerging crisis in domestic terrorism in Western nations cause researchers to again turn inward to focus on domestic problems or broaden their scope of investigation to examine the trend more globally? Will the recent events of another war in Europe (now focused, at the time of writing, on the escalating Russian invasion of Ukraine) provide a framework to again examine how people respond to heinous attacks on civilians, and whether they succumb to the effects of trauma or remain resilient?

Observations of binary systems indicate that main sequence stars follow an empirical mass-luminosity relation L ~ M^3. The physical basis for this can be understood by considering the two basic relations of stellar structure, namely hydrostatic equilibrium and radiative diffusion. In practice, the transport of energy from the stellar interior toward the surface sometimes occurs through convection instead of radiative diffusion; this has important consequences for stellar structure and thus for the scaling of luminosity.