Study of the Evolution of the Plastic Zone and Residual Stress in a Notched T-6061 Aluminum Sample.

Using experimental measurements and numerical computations, this paper focuses on studying the evolution of the plastic zone and how the residual stresses change in a notched T-6061 aluminum sample. Before the crack initiation, digital image measurements were taken to visualize the evolution of the plastic zone. After the sample was fractured, the material microstructure and the residual stresses around the cracked zone were characterized through optical microscopy and X-ray diffractometry. This article describes in detail how the plastic zone evolved around the notch before the crack initiation and shows the close agreement between experimental and numerical data during the load increment. The surface residual stress values around the tip of the notched sample were also measured and computed to give a better understanding of the affected region during the fracture process.

"The cops didn't make it any better": Perspectives on police and guns among survivors of gun violence.

BACKGROUND: Survivors of gun violence in the United States (US) are twenty times more likely to be re-injured with a firearm and three times more likely to be arrested under a violence or a weapons-related charge. The mechanisms for these outcomes are multifactorial and remain largely understudied. We aimed to examine perspectives on both the police and guns among survivors of guns violence. METHODS: We conducted a secondary analysis of qualitative data from a study that examined the post-hospitalization recovery experience of survivors of firearm violence. Using a conceptual framework derived from sociology literature and a coding team made up of researchers, community members and former police officers, we used directed content analysis to construct themes. RESULTS: The data set included interviews with 20 survivors of gun violence that were all Black males, aged 20-51 years. The recurring themes around the police included: (1) Legal cynicism: "I don't like police, none of them"; (2) Interactions with the police in a medical setting: "The cops didn't make it any better" and (3) Ambivalence around police presence within the community: "That's their job to protect me, too." Themes related to guns in the community encompassed: (1) The availability of guns: "Getting a gun is about as easy as buying a pair of sneakers"; (2) Symbolic meaning: "Guns give them courage"; (3) Social meaning: "I just let them know: I have a gun, too." and (4) Strategic meaning: "It's just for protection." CONCLUSIONS: Survivors of gun violence describe distrust for the police and an ecology of guns that confers symbolic, social and strategic meaning to owning a gun. Interventions to decrease gun violence should address the cultural value of a gun as well as focus on improving police relations with the community.

Survivors of gun violence and the experience of recovery.

BACKGROUND: Survivors of gun violence may develop significant mental health sequelae and are at higher risk for reinjury through repeat violence. Despite this, survivors of gun violence often return to the community where they were injured with suboptimal support for their mental health, emotional recovery, and well-being. The goal of this study was to characterize the posthospitalization recovery experience of survivors of gun violence. METHODS: We conducted a qualitative research study with a community-based participatory research approach. In partnership with a community-based organization, we conducted in-depth one-on-one interviews and used snowball sampling to recruit survivors of gun violence. We applied the constant comparison method of qualitative analysis to catalogue interview transcript data by assigning conceptual codes and organizing them into a consensus list of themes. We presented the themes back to the participants and community members for confirmation. RESULTS: We conducted 20 interviews with survivors of gun violence; all were black men, aged 20 years to 51 years. Five recurring themes emerged: (1) Isolation, physical and social restriction due to fear of surroundings; (2) Protection, feeling unsafe leading to the desire to carry a gun; (3) Aggression, willingness to use a firearm in an altercation; (4) Normalization, lack of reaction driven by the ubiquity of gun violence in the community; and (5) Distrust of health care providers, a barrier to mental health treatment. CONCLUSION: Survivors of gun violence describe a disrupted sense of safety following their injury. As a result, they experience isolation, an increased need to carry a firearm, a normalization of gun violence, and barriers to mental health treatment. These maladaptive reactions suggest a mechanism for the violent recidivism seen among survivors of gun violence and offer potential targets to help this undertreated, high-risk population. LEVEL OF EVIDENCE: Care management/Therapeutic V.