Chemokines have been a long-standing interest in the field of immunology due to their role in directing the migration of immune cells. Approximately a decade ago, chemokines and their receptors became a major focus area in cancer biology due to their role in directing the "migration", or metastasis, of cancer cells from tissues of origin to distant sites. A renewed interest in the role of chemokines in cancer has come with the expanding field of the tumor microenvironment, in particular, with a drive towards understanding the contributions of non-cancerous stromal cells, immune cells, and extracellular matrix components to the survival, growth, proliferation and invasive properties of cancer cells. These constituents of the microenvironment are known to release a variety of molecules including cytokines, growth factors, proteases and chemokines that modulate the growth and development of tumors. My dissertation work has focused on understanding the role of chemokines and their receptors in the cell survival, proliferation, and metastasis of cancer cells. Specifically, I have examined the functions and signaling pathways induced by the chemokine CXCL12 and its receptors, CXCR4 and CXCR7, in two types of cancer: Chronic Lymphocytic Leukemia (CLL) and breast cancer. To this end, a variety of traditional cellular biology, molecular biology and pharmacological approaches as well as more global phosphoproteomics methods were employed. Overall, this work demonstrates the importance of CXCL12 to the survival and malignancy of CLL and unveils numerous potential molecular targets for therapeutic intervention, including the proposed use of a multi-kinase inhibitor, sorafenib, for treatment of CLL. Additionally, investigation of the individual and combined contributions of CXCR4 and CXCR7 to breast cancer progression has provided insight into some important signaling differences and cross-modulation of these receptors. Using a mouse model for metastasis, we have demonstrated that although high CXCR4 expression promotes breast cancer metastasis, co-expression with high levels of CXCR7 dramatically reduces metastasis without reducing primary tumor growth. Mechanisms by which CXCR7 may modulate CXCR4 function are also explored. A better understanding of how chemokines function in the context of health and disease may provide promising leads for future drug discovery

Food sovereignty, the ability of communities and nations to determine their own food systems, is based on ecological relations between humans and our habitat. This article examines how human ecological relations with plants and animals contribute to the food sovereignty of indigenous communities in the Standing Rock Nation of the northern Great Plains. During the past one hundred and fifty years, the policies of the United States federal government have deliberately undermined these relations, including eradication of primary food sources, forced sedenterization on reservations, illegal land seizures, and compulsory reeducation of children at residential schools. The loss of food sovereignty has directly impacted the health of Standing Rock communities. Tribal government agencies, academic institutions, and nonprofit organizations in Standing Rock are working to enhance food sovereignty by revitalizing relations with plants and animals used to prepare healthy traditional foods. Interviews with elders and other participants in these activities reveal that tradition and sustainability are important dimensions of indigenous food sovereignty.

Cocaine-induced midline destructive lesions (CIMDL) occur in a small subset of cocaine users, who clinically present with inflammation and necrosis of facial midline structures such as the palate, nasal septum, turbinates, and sinuses. We present a patient with CIMDL occurring concomitantly with ulcers on the cheek and upper trunk. Multiple biopsy specimens from the cutaneous and mucosal lesions consistently showed a dense dermal/submucosal infiltrate of neutrophils and plasma cells, without vasculitis or thrombosis. The ulcers resolved following cessation of cocaine use.

Myxofibrosarcoma may present as a dermal or subcutaneous nodule, often on the extremity of an elderly patient. We present a case of myxofibrosarcoma on the lower leg of a 77-year-old man, which illustrates the deeply infiltrative growth pattern of these tumors, as well as the potential for superficial biopsies to show lower grade histopathologic features than subsequent excision specimens.

Prairie voles have emerged as an important rodent model for understanding the neuroscience of social behavior. Prairie voles are well known for their capacity for pair bonding and alloparental care. These behavioral phenomena overlap with human social behavior but are not commonly observed in traditional rodent models. In this article, we highlight the many benefits of using prairie voles in neuroscience research. We begin by describing the advantages of using diverse and non-traditional study models. We then focus on social behaviors, including pair bonding, alloparental care, and peer interactions, that have brought voles to the forefront of social neuroscience. We describe many additional features of prairie vole biology and behavior that provide researchers with opportunities to address an array of research questions. We also survey neuroethological methods that have been used with prairie voles, from classic to modern techniques. Finally, we conclude with a discussion of other vole species, particularly meadow voles, and their own unique advantages for neuroscience studies. This article provides a foundation for researchers who are new to working with voles, as well as for experienced neuroscientists who want to expand their research scope. © 2021 Wiley Periodicals LLC.

As extreme events increase in frequency, flow-disrupting large-scale structures become ever more susceptible to collapse due to local scour effects. The objective of this study was to validate the functionality of passive, flow-excited scour sensors that can continue to operate during an extreme event. The scour sensors, or piezo-rods, feature continuous piezoelectric polymer strips embedded within and along the length of slender cylindrical rods, which could then be driven into the soil where scour is expected. When scour erodes away foundation material to reveal a portion of the piezo-rod, ambient fluid flow excitations would cause the piezoelectric element to output a voltage response corresponding to the dynamic bending strains of the sensor. The voltage response is dependent on both the structural dynamic properties of the sensor and the excitation fluid’s velocity. By monitoring both shedding frequency and flow velocity, the exposed length of the piezo-rod (or scour depth) can be calculated. Two series of experimental tests were conducted in this work: (1) the piezo-rod was driven into sediment around a mock pier to collect scour data, and (2) the piezo-rod was used to monitor its own structural response by collecting vortex-shedding frequency data in response to varied flow velocities to establish a velocity–frequency relationship. The results showed that the piezo-rod successfully captured structural vortex-shedding frequency comparable to state-of-practice testing. A one-dimensional numerical model was developed using the velocity–frequency relationship to increase the accuracy of voltage-based length prediction of the piezo-rod. Two-dimensional flow modeling was also performed for predicting localized velocities within a complex flow field. These velocities, in conjunction with the velocity–frequency relationship, were used to greatly improve length-predictive capabilities.

Background

As mobile devices are becoming ubiquitous, technology-based interventions provide a promising strategy to positively influence health behaviors of families with young children. However, questions remain about the feasibility and acceptability of intervention delivery via mobile apps in low-income, rural settings and among families with preschoolers.

Objective

The aims of this study were to understand the content and context of mobile device use for preschoolers; explore parent beliefs on this topic, including the acceptability of intervention delivery via mobile devices; and test a prototype of an app to encourage preschoolers' physical activity with both parents and children.

Methods

Parents (n=29) were recruited from 5 preschool centers in eastern, rural Colorado to complete a semistructured telephone interview regarding preschoolers' mobile device use. A second sample of parents (n=31) was recruited from the same preschool centers to view the app prototype independently and provide feedback. A third sample of preschool children (n=24) was videotaped using the app in small groups to measure engagement and record their responses to the app.

Results

Five key content areas emerged from the telephone interviews: (1) mobile devices are an important part of families' everyday routines, and parents have parameters governing their use; (2) parents often use mobile devices as a tool for behavior management; (3) parents clearly distinguish between mobile device use for learning versus entertainment; (4) parents have an overarching desire for balance in regard to their child's mobile device use; and (5) parents were generally supportive of the idea of using mobile apps for intervention delivery. From the app prototype testing with parents, participants reacted positively to the app and felt that it would be useful in a variety of situations. Testing with preschoolers showed the children were highly engaged with the app and a majority remained standing and/or actively moving through the entire length of the app.

Conclusions

Mobile devices are already integrated into most families' daily routines and appear to be an acceptable method of intervention delivery in low-income families in rural Colorado. The physical activity app represents an innovative way to reach these families and, with further improvements based on participant feedback, will provide children with a unique opportunity to practice key movement skills.

Abstract: Local scour is a growing cause of bridge failure in the United States and around the world. In the next century, the effects of climate changes will make more bridges susceptible to scour failure more than ever before. This study aims to harness the spatially continuous monitoring capabilities of ultrasonic time-domain reflectometry to detect a soil interface for the purposes of scour monitoring. In this study, a long, slender plate is coupled with two flexible piezoelectric devices that propagate Lamb waves along the length of the plate to form the scour sensor. The sensor was tested for sensitivity to external pressure using metal weights and was able to detect the position of the pressure up at a length of up to ∼20 feet. The sensor was tested under simulated scour conditions, being buried in sand at various depths. The results show that the Lamb wave scour sensor is capable of reliably detecting a soil interface at 1 ft intervals. The scour sensor was also able to detect uncompacted soil interfaces, which is important considering the issue of scour hole refill following an extreme event.