Artful science of hands-on medicine

Thesis (S.M. in Science Writing)--Massachusetts Institute of Technology, Dept. of Humanities, Graduate Program in Science Writing, 2008.Includes bibliographical references (leaves 39-42).Listening to lung sounds, feeling the pulse, observing posture and gait-these are just a few of the examinations that doctors perform on their patients. A physical exam exists for every organ, from the brain to the bones of the feet, each carried out with the physician's senses. For thousands of years, humans had been solely responsible for this exam ritual, until the emergence of diagnostic equipment-CT scans, MRI scans, ultrasounds, echocardiograms, mammograms, and more. In some cases, these devices replaced the physical exam. But in areas of the world where technology is unavailable, and even in places where it exists, many physicians and healthcare professionals cannot or will not to cede their tasks to tools. Their goal: to maintain an environment in which technology and the learned senses can coexist; an environment in which the physical exam remains an integral part of medicine.by Allyson T. Collins.S.M.in Science Writin

Genome Assembly Improvement and Mapping Convergently Evolved Skeletal Traits in Sticklebacks with Genotyping-by-Sequencing.

Marine populations of the threespine stickleback (Gasterosteus aculeatus) have repeatedly colonized and rapidly adapted to freshwater habitats, providing a powerful system to map the genetic architecture of evolved traits. Here, we developed and applied a binned genotyping-by-sequencing (GBS) method to build dense genome-wide linkage maps of sticklebacks using two large marine by freshwater F2 crosses of more than 350 fish each. The resulting linkage maps significantly improve the genome assembly by anchoring 78 new scaffolds to chromosomes, reorienting 40 scaffolds, and rearranging scaffolds in 4 locations. In the revised genome assembly, 94.6% of the assembly was anchored to a chromosome. To assess linkage map quality, we mapped quantitative trait loci (QTL) controlling lateral plate number, which mapped as expected to a 200-kb genomic region containing Ectodysplasin, as well as a chromosome 7 QTL overlapping a previously identified modifier QTL. Finally, we mapped eight QTL controlling convergently evolved reductions in gill raker length in the two crosses, which revealed that this classic adaptive trait has a surprisingly modular and nonparallel genetic basis

Integrating Smart Ceiling Fans and Communicating Thermostats to Provide Energy-Efficient Comfort

The project goal was to identify and test the integration of smart ceiling fans and communicating thermostats. These highly efficient ceiling fans use as much power as an LED light bulb and have onboard temperature and occupancy sensors for automatic operationbased on space conditions. The Center for the Environment (CBE) at UC Berkeley led the research team including TRC, Association for Energy Affordability (AEA), and Big Ass Fans (BAF). The research team conducted laboratory tests, installed99 ceiling fans and 12 thermostats in four affordable multifamily housing sites in California’s Central Valley, interviewed stakeholders to develop a case study, developed an online design tool and design guide, outlined codes and standards outreach, and published several papers.The project team raised indoor cooling temperature setpoints and used ceiling fans as the first stage of cooling; this sequencing of ceiling fans and air conditioningreducesenergy consumption, especially during peak periods, while providing thermal comfort.The field demonstration resulted in 39% measured compressor energy savings during the April–October cooling seasoncompared to baseline conditions, normalized for floor area. Weather-normalized energy use varied from a 36% increase to 71% savings, withmedian savings of 15%.This variability reflects the diversity in buildings, mechanical systems, prior operation settings, space types, andoccupants’ schedules,preferences, and motivations. All commercial spaces with regular occupancy schedules (and twoof the irregularly-occupied commercial spaces and one of the homes) showed energy savings on an absolute basis before normalizing for warmer intervention temperatures,and 10 of 13 sites showed energy savings on a weather-normalized basis. The ceiling fans provided cooling for one site for months during hot weather when the coolingequipment failed.Occupants reported high satisfaction with the ceiling fans and improved thermal comfort. This technology can apply to new and retrofit residential and commercial buildings

The Influence of Rejection Episodes in Recipients of Bilateral Corneal Grafts

Author version made available in accordance with Publisher copyright policy.We investigated whether a rejection episode in one graft was associated with rejection in the other graft, in recipients with bilateral corneal transplants. In a prospectively maintained, national register of 14 865 followed corneal grafts, 1476 patients with bilateral penetrating corneal grafts were identified. Occurrence of rejection was a risk factor for graft failure (p < 0.0001). Logistic regression was used to calculate the adjusted odds ratio for rejection in one eye following rejection in the other eye. In the subset of 1118 patients with bilateral grafts but no history of previous grafts or rejections in either eye, the adjusted odds ratio for a rejection episode in the first eye following rejection in the second was 3.27 (95% confidence interval, CI 1.85, 5.79; p < 0.001). The adjusted odds ratio was 2.04 (95% CI 1.07, 3.91; p = 0.03) for rejection in the second eye following rejection in the first. The median time between the first rejection episode in one eye and the first rejection episode in the other eye was 15 months. Patients with bilateral corneal grafts who suffer a graft rejection episode in one eye are at significantly greater odds of suffering a rejection episode in the other corneal transplant

Cyclic behaviour of hollow and concrete-filled circular hollow section braces

Presented in this thesis is an investigation on the response of hot-finished and cold formed, hollow and concrete-filled circular hollow section braces in earthquake resisting concentrically braced frames. The role of these braces is to act as structural ‘fuses’ in the frame, dissipating the seismic energy by undergoing plastic deformations. Circular hollow sections offer aesthetic and structural advantages over conventional rectangular hollow sections owing to the uniformity of the section geometry. Distinct behaviour is observed between cold formed and hot-finished tubes, since the cold formed sections retain a higher degree of residual stresses from manufacturing. Braces subjected to cyclic loading fail after the occurrences of global and local buckling, but the performance can be enhanced by employing concrete infill. The concrete-filled steel tube is an optimum combination of the two materials, resulting in an efficient, economic and practical structural member. Experiments were performed in which cyclic axial loading was applied to hollow and composite braces of each section type. Hot-finished specimens exhibited superior ductility to cold formed members. Concrete infill enhanced the tensile resistance for members of all lengths, the compressive resistance of shorter members and the number of cycles to failure. Finite element models were subsequently developed with ABAQUS® software, using the inbuilt nonlinear isotropic/kinematic hardening model and the damaged plasticity model to define the steel and concrete characteristics. Reliable simulations were achieved for the hollow braces but further work is required for the composite braces. Both local and global slenderness values influenced the specimen response. Expressions were proposed to predict the displacement ductility and energy dissipation capability of hollow braces in terms of these parameters. The findings suggest that distinct guidelines could be developed for introduction into Eurocode 8 for each steel section type, and that the benefits of concrete infill could be taken into account in dissipative design

Between asylum and independence : toward a system of community care for people with long-term mental illness

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1988.Includes bibliographical references.by Elizabeth T. Murphy.M.C.P

An archaeology of psychological knowledge as technology of power in Africa

The relevance of psychology in Africa is increasingly debated by psychologists. The subject stands accused of continuing a colonial tradition of oppression through its Eurocentrism and failure to attend to the needs of African societies. The relevance debate raises questions around the relationship between power, knowledge, psychology, and African history. This study attempts to excavate the conditions of possibility of the debate, by construing an archaeology of psychological knowledge as technology of power in the African context. It assumes a constructivist stance, employs textual and narrative analogies, and follows Foucault's conceptualisation of the relation between power and knowledge. Five strata of knowledge emerging historically in Africa, each embodying distinctive approaches to knowledge, are described: Indigenous African knowledge, African Islamic knowledge, African Christianity, knowledges of Enlightenment, and knowledges of resistance. These knowledges, their psychological dimensions, as well as the circulation of power within and between them, are explored, and historical processes of subjugation and resistance highlighted. Western psychology, as technology of modern power, is situated within modernism and the narratives ofEnlightenment, which also provided the conditions of possibility of colonialism. The dominant narratives of relevance are related to those of African resistance and the limitations of psychology are conceptualised in terms of those pertaining to modernism. Possible postmodern avenues to the liberation of both psychology and its subjects, that are relevant to African contexts, are suggested.PsychologyD. Litt. et Phil. (Psychology

The clean air strategy for Alberta : a case study in consensus decision making for sustainable development

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1992.Includes bibliographical references (leaves 98-104).by Carol T. Reardon.M.C.P

Disentangling the effects of cannabis and cigarette smoking on impulsivity

BACKGROUND: Cannabis smoking and cigarette smoking often co-occur, yet limited research has investigated the potentially different role impulsivity may play when these behaviours occur in isolation, compared with in combination. AIMS: This study examined trait and behavioural impulsivity as a function of both cigarette and cannabis smoking. METHODS: Trait impulsivity (BIS-11) was compared between 44 non-smokers, 76 cigarette only, 47 cannabis only and 58 cannabis plus cigarette smokers. The effects of cigarette and cannabis smoking on behavioural impulsivity (stop-signal and information sampling tasks) were then assessed in 87 of these participants during a laboratory session. RESULTS: Trait impulsivity was significantly higher in cigarette smokers than non-smokers, irrespective of cannabis use, except for motor impulsivity, where cigarette smoking was only associated with elevated trait impulsivity in non-smokers of cannabis. Dimensions of trait impulsivity were significantly positively related to cigarette smoking frequency and nicotine dependence, but not to cannabis smoking frequency or dependence. Smoking cigarettes or cannabis was associated with significantly impaired reflection impulsivity relative to not smoking either substance. However, no additional increases in reflection impulsivity were observed in those who smoked both cigarettes and cannabis. No group differences in response inhibition were detected. CONCLUSIONS: Heightened trait impulsivity appears to be uniquely related to cigarette smoking, whilst the smoking of cigarettes or cannabis is associated with impairments in reflection impulsivity. Improved outcomes for treating cannabis dependence may result from encouraging concomitant cigarette smokers to cease using both drugs simultaneously in order to reduce heightened impulsivity and risk of relapse