Conceptual Framework and Physical Implementation of a Systematic Design Strategy for Tissue-Engineered Devices

Tissue-engineered and biologically inspired devices promise to advance medical implants, robotic devices and diagnostic tools. Ideally, biohybrid constructs combine the versatility and fine control of traditional building substrates with dynamic properties of living tissues including sensory modalities and mechanisms of repair, plasticity and self-organization. These dynamic properties also complicate the design process as they arise from, and act upon, structure-function relationships across multiple spatiotemporal scales that need to be recapitulated in the engineered tissue. Biomimetic designs merely copying the structure of native organs and organisms, however, are likely to reflect evolutionary constraints, phenotypic variability and environmental factors rather than rendering optimal engineering solutions. This thesis describes an alternative to biomimetic design, i.e., a systematic approach to tissue engineering based on mechanistic analysis and a focus on functional, not structural, approximation of native and engineered system. As proof of concept, the design, fabrication and evaluation of a tissue-engineered jellyfish medusa with biomimetic propulsion and feeding currents is presented with an emphasis on reasoning and strategy of the iterative design process. A range of experimental and modeling approaches accomplishes mechanistic analysis at multiple scales, control of individual and emergent cell behavior, and quantitative testing of functional performance. The main achievement of this thesis lies in presenting both conceptual framework and physical implementation of a systematic design strategy for muscular pumps and other bioinspired and tissue-engineered applications.</p

Penerapan penggunaan strategi pembelajaran improve terhadap hasil belajar pada pokok bahasan hidrokarbon

Proses pembelajaran kimia memiliki dua hal yang tidak terpisahkan, yaitu kimia sebagai produk temuan ilmuan dan kimia sebagai proses (kerja ilmiah). Sehingga dalam pembelajaran kimia seharusnya bukan hanya menekankan pada penguasaan konsep saja tetapi juga pada proses penemuan konsep dengan melibatkan aktivitas metakognitif siswa. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan strategi pembelajaran IMPROVE terhadap hasil belajar siswa kelas X MAN 2 Samarinda pada pokok bahasan hidrokarbon. Sampel dalam penelitian ini adalah siswa kelas X-l yang berjumlah 35 orang yang diberi perlakuan menggunakan strategi pembelajaran IMPROVE dan siswa kelas X-2 yang berjumlah 35 orang&nbsp;yang diberi perlakuan menggunakan strategi pembelajaran konvensional (kelas kontrol pembanding). Hasil penelitian menunjukkan nilai rata-rata hasil belajar siswa kelas X-l yaitu 89,5 lebih tinggi daripada nilai rata-rata hasil belajar siswa kelas X-2 yaitu 83. Hasil ini kemudian dianalisis menggunakan uji t dengan variansi homogen dan diperoleh nilai thitung: -4,58 dan -ttabel dengan taraf signifikansi 5% = -2,0. Karena -thitung &lt; -ttabel maka H0 ditolak dan Ha diterima, sehingga dapat disimpulkan bahwa terdapat pengaruh penggunaan strategi pembelajaran IMPROVE terhadap hasil belajar pada pokok bahasan hidrokarbon siswa kelas X MAN 2 Samarind

Design standards for engineered tissues

Traditional technologies are required to meet specific, quantitative standards of safety and performance. In tissue engineering, similar standards will have to be developed to enable routine clinical use and customized tissue fabrication. In this essay, we discuss a framework of concepts leading towards general design standards for tissue-engineering, focusing in particular on systematic design strategies, control of cell behavior, physiological scaling, fabrication modes and functional evaluation

Induced drift by a self-propelled swimmer at intermediate Reynolds numbers

Swimming organisms have been proposed to contribute to the mixing of stratified water in the ocean, thereby facilitating the vertical transport of nutrients and dissolved gases. In general, mixing results from increasing the interface available for molecular diffusion between neighboring fluid volumes. At high Reynolds numbers (Re), swimmers generate such interfaces through their turbulent wake structures. At lower Re, however, turbulent mixing becomes ineffective as viscous effects dissipate small-scale fluid motions as heat, and diffusion is not significantly enhanced. In this regime, it appears that the dominant mechanism for mixing by a swimmer is induced drift, i.e., the propagation and stretching of a fluid volume by a moving body's pressure field, which increases the diffusion-enabling interface between the drift volume and surrounding fluid. The ratio of drift volume to body volume is called the “added-mass” coefficient and depends on the shape of the body. Importantly, previous computational analysis suggested that the total drift volume increases at low and intermediate Re, 3 implying that in contrast to turbulent mixing, mixing through induced drift becomes more efficient in viscous conditions. As pointed out by others, the limitation of previous numerical simulations, however, is that the simulated objects were towed through viscous fluid, which is dynamically distinct from a self-propelled swimmer. Using qualitative flow visualization, we here demonstrate the presence of induced drift in self-propelled swimmers operating at intermediate Re (1–100). In these experiments, the spatiotemporal pattern of a fluid volume initially surrounding a juvenile Moon jellyfish ( Aurelia aurita) is visualized using Fluorescein dye (see Fig. 1 ). For details on the experimental methods see supplemental material in Ref. 13

Social Justice Education: Impacts on Social Attitudes

Paramount to multicultural social work practice is acquiring a comprehensive understanding of oppressed and vulnerable populations who often lack access to healthcare and economic resources. A practitioner’s self-awareness of social attitudes can provide a foundation for developing cultural competency skills. Using a pretest posttest design, social attitudes of Master of Social Work (MSW) students enrolled in a required social justice course were examined (N=85). A repeated-measure MANOVA indicated significant main effects on: 1) within subject factor of time on students’ cognitive attitudes towards racial diversity, affective attitudes toward racial diversity, and women equity following students’ exposure to the social justice course, and 2) between subject on the racial diversity affective subscale. Implications for practice are discussed

An engineering approach to quantify geomechanical safety factors in UGS programs

Abstract. Underground Gas Storage (UGS) has become one of the most widely used practices to cope with seasonal peaks in energy consumption. The planning of any new UGS facility, or its upgrading to increase the working gas volume and reservoir performance, must be supported by an evaluation of possible induced effects on the environment. From a geomechanical point of view, storage activity results in a cyclic change in stress and deformation in the reservoir rock and the surrounding formations. The main environmental issues to be accounted for when natural fluid pore pressure is planned to be exceeded are the following: (a) the differential displacements at the land surface possibly mining the integrity of ground structure; (b) the integrity of the reservoir and caprock; (c) the possible reactivation of faults, if the target reservoir is located in a faulted basin; and (d) the vertical upheaval and land subsidence that can impact on the surface drainage network in low lying coastal areas. We present an original methodology for evaluating the geomechanical safety of UGS activities using an approach derived from what is traditionally applied in the structural design of buildings. A safety factor, a margin of security against risks, is defined for each of the geomechanical issues listed above. First, a 3D FE-IE numerical model is developed to reproduce the stress and displacement due to the UGS program under evaluation. Then the reservoir pressure is increased until the "failure" condition is reached allowing to evaluate how far the project designed condition is from the above limit. The proposed approach is applied to Romagna, a depleted gas reservoir in Northern Italy converted to UGS, with the aim of investigating the safety of the project to increase the reservoir pressure up to 120 % pi, where pi is the original reservoir pressure before the start of primary production. The 3D geomechanical model has been developed using recent 3D seismic data, land displacements by InSAR, lab tests on reservoir and caprock samples, in-situ Modular Formation Dynamic Tester (MDT) stress tests, and large background information acquired from other UGS reservoirs located in the same sedimentary basin. The analysis outcome has revealed that the investigated scenario is safe, with safety factor larger than 1, in the range from 1.2 to 4. The most critical condition (the smallest safety factor) has been obtained in relation to the mechanical integrity of the reservoir formation, under very conservative conditions (cohesion = 0, friction angle = 30∘)

Checklist for One Health Epidemiological Reporting of Evidence (COHERE).

One Health is defined as the intersection and integration of knowledge regarding humans, animals, and the environment, yet as the One Health scientific literature expands, there is considerable heterogeneity of approach and quality of reporting in One Health studies. In addition, many researchers who publish such studies do not include or integrate data from all three domains of human, animal, and environmental health. This points to a critical need to unify guidelines for One Health studies. This report details the Checklist for One Health Epidemiological Reporting of Evidence (COHERE) to guide the design and publication format of future One Health studies. COHERE was developed by a core writing team and international expert review group that represents multiple disciplines, including human medicine, veterinary medicine, public health, allied professionals, clinical laboratory science, epidemiology, the social sciences, ecohealth and environmental health. The twin aims of the COHERE standards are to 1) improve the quality of reporting of observational or interventional epidemiological studies that collect and integrate data from humans, animals and/or vectors, and their environments; and 2) promote the concept that One Health studies should integrate knowledge from these three domains. The 19 standards in the COHERE checklist address descriptions of human populations, animal populations, environmental assessment, spatial and temporal relationships of data from the three domains, integration of analyses and interpretation, and inclusion of expertise in the research team from disciplines related to human health, animal health, and environmental health

Captive Breeding Protocols and Their Impact on Genetic Diversity in White-footed Mice (Peromyscus leucopus): Implications for Threatened and Endangered Species

Captive breeding protocols used in zoos often are aimed at increasing population sizes and retaining genetic diversity of endangered species. However, captive breeding causes genetic adaptation to captivity that can lead to an overall decrease in genetic diversity and reduce chances of a successful reintroduction to the wild. In this study, we assess how 3 different breeding protocols—random mating, preferential breeding of individuals with the lowest mean kinship scores, and selection for docility—affect the variability of mitochondrial DNA in white-footed mice (Peromyscus leucopus). We used mice that were captured from the wild but were mated for up to 20 generations using one of the aforementioned breeding protocols. Using animals from generations 0, 6, and 19, as well as the wild source population, we sequenced the mitochondrial D-loop in 2 replicate populations representing each of the 3 breeding protocols. Initial sequences indicate there is genetic variation at this mitochondrial locus, and further sequencing will allow us to quantify the genetic diversity maintained under each breeding protocol. These results will increase our understanding of the decline in genetic diversity due to adaptation to captivity. Thus, our results will have direct relevance for the maintenance and growth of zoo populations of critically endangered species

A motivational tool that utilizes the psychological, social and physical factors that provide and prevent motivation to create an assistive, in-home tool for use between office sessions while undergoing physical therapy

The physical body is the one thing we have with us from the day we enter life to the day we depart. Most of us take for granted the fact that our bodies and all the systems therein do what we expect them to without pain or discomfort. It is important to keep this vessel as functional as possible. In this society where independence and mobility are highly valued, it is often thought that the body needs to be in working order to take full advantage of the world around us. It is easier to live when the body is in complete working order since our society is one designed for those with independent mobility. Although it may be difficult to see directly after an injury, quality of life is enhanced when mobility is regained. Reduced functionality leads to physical and emotional debilitation. Reduced functionality may occur from an accident, disease, injury or genetic abnormalities. According to The Disability Statistics Rehabilitation Research and Training Center, the fourth most common condition (4.6% of all conditions) which causes individuals to limit activities, is the impairment of lower extremities, greatly effecting quality of life (Persoon, 2004 and Rikli, 2005) Among the lower extremities, impairments, knee joint injuries and chronic pain are common. A 2003 interview from ABC television quotes Scott Lephart, Ph.D. as saying, knee injuries are occurring in epidemic proportions. Knee injuries constitute only about 15% of all sports injuries but are 50% of visits to sports doctors, indicating that when they happen, they are usually significant. (McLaughlin) This project will focus on lower extremity injuries since it is the largest orthopedically limiting condition. Physical Therapy is one of the medical options used to regain normal functionality of an injured body part or to reduce chronic pain from a musculoskeletal condition. Patients are referred to PTs by a physician, orthopedist or surgeon after an injury. The referrals come after a physician has confirmed that a patient needs to regain functionality and reduce pain after surgery or the incident of chronic pain. Patients may be seen at a variety of locations including the hospital (both in-patient and out-patient), a private PT office, at home, in a nursing home, or in an athletic center. The profile of patients who see PTs is changing and growing. The population of the United States shows a breakdown of 49.1% and 50.1% males to females. (Hicks et al., 2004) In therapeutic settings, the genders are unequally represented with 44.2% of patients being male and 55.8% being female. It has been hypothesized that more women are participating in sports and suffering subsequent injuries (Brisette, 2004 and abclocal.go.com). Compared to their representation in the U.S. general population, middle aged (50-74) and older (74+) adults were overrepresented in the demographics of those seen by a physical therapist. Most frequently seen patients were middle-aged adults (50-74) and young adults (20-49). The population is living longer and, through modern medicine, are able to live with chronic and disabling conditions. These conditions require treatment possibly resulting in the rise of patient statistics weighted towards the older population (Brisette, 2004). A patient participating in a course of physical therapy has not only to contend with the physical ramifications of an injury, but also the psychological issues (Uppal, 2003). While bones, ligaments and cartilage are healing, patients are required to participate in a series of exercises both at home and in a therapists office. While rehabilitating at home, patients may find it difficult to remember, make time or feel motivated to do these exercises. These issues are a large obstacle on the path to wellness. The design solution presented in this thesis looks at the factors which influence motivation including community, positive and negative feedback, tracking and goals. The proposed solution will incorporate information from the fields of psychology, wearable technology and physical therapy. Pain and injury do not necessarily motivate individuals to participate in a course of a HEP (home exercise program) which can eventually lead to better health. Knowing a product will make you feel better does not make you use it. A goal is not enough. To further motivate individuals, aspects of fun, community, autonomy and competence can greatly improve a persons desire to heal (Uppal, 2003 and Deci-Ryan and Coleman, 1998). A customizable, networked solution is proposed where individuals may use one, two or all three parts of an integrated system to track daily and overall progress, work with a buddy and communicate with a therapist. It is hypothesized that with this system, patients will be more motivated to participate in at home physical therapy to regain full functionality. The research and design process took part in various stages. Processes moved from the general to the specific as research and interviews informed the work.M.S.Committee Chair: Chung, Wayne; Committee Member: Gromala, Diane; Committee Member: Ringholz, Davi