Direct Freeform Fabrication of Spatially Heterogeneous Living Cell-Impregnated Implants

The objectives of this work are the development of the processes, materials, and tooling to directly “3-D print” living, pre-seeded, patient-specific implants of spatially heterogeneous compositions. The research presented herein attempts to overcome some of the challenges to scaffolding, such as the difficulty of producing spatially heterogeneous implants that require varied seeding densities and/or cell-type distributions. In the proposed approach, living implants are fabricated by the layer-wise deposition of pre-cell-seeded alginate hydrogel. Although alginate hydrogels have been previously used to mold living implants, the properties of the alginate formulations used for molding were not suitable for 3-D printing. In addition to changing the formulation to make the alginate hydrogels “printable,” we developed a robotic hydrogel deposition system and supporting CAD software to deposit the gel in arbitrary geometries. We demonstrated this technology’s capabilities by printing alginate gel implants of multiple materials with various spatial heterogeneities, including, implants with completely embedded material clusters. The process was determined to be both viable (94±5% n=15) and sterile (less than one bacterium per 0.9 µL after 8 days of incubation). Additionally, we demonstrated the printing of a meniscus cartilage-shaped gel generated directly from a CT Scan. The proposed approach may hold advantages over other tissue printing efforts [5,9]. This technology has the potential to overcome challenges to scaffolding and could enable the efficient fabrication of spatially heterogeneous, patient-specific, living implants.Mechanical Engineerin

A guideline for heavy ion radiation testing for Single Event Upset (SEU)

A guideline for heavy ion radiation testing for single event upset was prepared to assist new experimenters in preparing and directing tests. How to estimate parts vulnerability and select an irradiation facility is described. A broad brush description of JPL equipment is given, certain necessary pre-test procedures are outlined and the roles and testing guidelines for on-site test personnel are indicated. Detailed descriptions of equipment needed to interface with JPL test crew and equipment are not provided, nor does it meet the more generalized and broader requirements of a MIL-STD document. A detailed equipment description is available upon request, and a MIL-STD document is in the early stages of preparation

A Study of the Effect of Quinhydrone on the Time of Set of Silicic Acid Gells and of the Effect of Silicic Acid Gel on the Determination of pH by the Quinhydrone Electrode

The studies discussed in this report are supplementary to the work being done at Union College on silicic acid gels. In as much data has been taken in this work using pH as determined by the quinhydrone electrode, it was desired that a study be made of the effect of quinhydrone on the gel and of gel on the quinhydrone determinations. The pH of gels during their setting has been worked on and the first part of the experiment deals with the effect of quinhydrone on the time of set of silicic acid gel. Then it was desired to know wether a gel had any effect on the determination of the pH by means of the quinhydrone set up. It had been thought that there was no effect in either case but there was no experiemtnal evidence to show proof

Composing Online: A Case Study of Embodiment, Digitality, and YouTube

This study examines YouTube channel, ContraPoints, by trans woman Natalie Wynn. It begins with close readings and analyses of an example video and body of comments from Wynn’s oeuvre that draw conclusions about how trans embodiment intersects with online, multimodal composing. The study finds that, in her video “Beauty,” Wynn’s bodily presentation and rhetorical attitudes towards dominant norms of gender and sexuality constantly shift. Furthermore, the study uncovers evidence that commenter attitudes about gender and sexuality in the video “Autogynephilia” likewise shift as a result of encounters with the video and with other commenters. Next, the study reads the YouTube video page as an assemblage composed of smaller assemblages, or modules. I discover that each of the modules relate to one another in such a way as to endow the YouTube video page assemblage with the capacities to enter social justice movements, yet the specific properties of the modules on ContraPoints video pages fail to provide the sufficient conditions to exercise this capacity. Nevertheless, the study concludes that ContraPoints video page assemblages do have the capacity to generate interpersonal, communal reflections on complex issues around gender and sexuality, reflections that may give rise to changing beliefs. These belief changes are necessary for any future community-building that may enable social justice movements aimed at expanding rights around gender and sexuality. This case study, then, offers one answer among infinite possible answers to Phil Bratta and Scott Sundvall’s question of how composers with diverse embodiments address systems of domination using digital technology. The study also suggests that assemblage theory represents a productive framework for interpreting online, multimodal compositions that incorporate large bodies of information, or big-data assemblages

A Suggested Plan For The Education Of The Physically Handicapped Children In The Waco Elementary Schools

The writer became interested in the problem of the education of physically handicapped children in the Waco, Texas School System some years ago. Observing the neglect of this group, she decided to make a study of ways in which they can best be educated in regular schools where no special provisions are made for them. It has been recognized that the schools alone cannot solve the problem of social maladjustment of handicapped children because the situation is complicated by certain economic conditions and by the personality development of the handicapped child. Other agencies should share the responsibility with the school or take it up when the school lays it down. A well-planned coordinated program in which various agencies help to contribute to this much-neglected group is a definite means of meeting their needs in a desirable way. What the school should do is suggested, directly or indirectly, in connection with the presentation of facts of this study. it is hoped that in the light of these facts, many school systems will find it possible to make further studies of local situations, We have come to realize that more can be done and must be done in the interests of this neglected group if they are to be helped in finding their rightful places in the society in which they live

Adolescent Depressive Symptoms and Substance Use: The Mediating Influence of Health Service Utilization

A large number of American adolescents suffer from depression and the consequences have been shown to be detrimental to their well-being. Adolescent substance use is also an increasing social problem due to the high usage rates and negative lifelong consequences for users. This paper explores the relationships between victimization, substance use, psychological health service utilization, and depressive symptoms in a sample of 4,757 adolescents. Using two waves of data from the National Longitudinal Study of Adolescent Health (Add Health), the results revealed a positive relationship between victimization and adolescent depressive symptoms, even after controlling for several demographic variables and previous depressive symptoms. However, victimization was only moderately associated with depressive symptoms, indirectly through cigarette or marijuana use. Moreover, psychological health service utilization partially mediated the significant association between adolescent substance use (cigarette or marijuana) and adolescent depressive symptoms. In conclusion, adolescents who experience higher levels of victimization may be more likely to use cigarettes or marijuana, which is positively associated with utilizing psychological health services, thereby elevating the risk of adolescent depressive symptoms. Intervention to reduce adolescent substance use may reduce vulnerability to adolescent depressive symptoms. Advisor: Kimberly A. Tyle

Emerging Practices in K-6 Multimedia Methods of Instruction in the Bethel School District

The purpose of this study was to assess and describB the conditions and practices in the Bethel School District\u27s elementary schools with regard to the use of a multimedia approach to instruction. A sample of the 260 classroom teachers, 13 principals, and 13 learning resource center specialists in the Bethel School District\u27s 13 elementary schools (K-6) were surveyed using questionnaires covering the implementation of multimedia methods of instruction. The results showed current multimedia methods of instruction are rare in the elementary classrooms of the Bethel School District because of a lack of technological inservice and current multimedia hardware

An analysis of astronaut performance capability in the lunar environment. Volume 1 - Performance problems and requirements for additional research

Analyzing data on expected astronaut performance in lunar environmen

Sea Water Fish in a Freshwater Pond: An Institutional Approach to Understanding Cooperative Scarcity in the United States

There is remarkable cooperative organization scarcity in the United States. Particularly in the credit union and worker cooperative sectors, this scarcity is not satisfactorily explained by neo-classical economic models that assume competitive conditions and profit-maximizing organizations. This paper supplements the conventional economic understandings of credit union and worker cooperative scarcity with an institutional analysis. Mechanisms of coercive, mimetic, and normative institutional isomorphism developed in DiMaggio and Powell’s theory of organizational isomorphism are applied to provide greater understanding of credit union and worker cooperative scarcity in the US. It appears that these forces of isomorphism work in conjunction with one another, as well as with competitive forces of isomorphism, to cyclically reproduce the scarcity of credit unions and worker cooperatives which prevails in the US

Consideration of radar target glint from ST during OMV rendezvous

The nature of radar target glint and the factors upon which it depends when using the Hubble Space Telescope as a radar target is discussed. An analysis of the glint problem using a 35 MHz or 94 MHz radar on the orbital maneuvering vehicle is explored. A strategy for overcoming glint is suggested