206 research outputs found
Deep Learning Approach for Dynamic Sampling for High-Throughput Nano-DESI MSI
Mass Spectrometry Imaging (MSI) extracts molecular mass data to form visualizations of molecular spatial distributions. The involved scanning procedure is conducted by moving a probe across and around a rectilinear grid, as in the case of nanoscale Desorption Electro-Spray Ionization (nano-DESI) MSI, where singular measurements can take up to ~5 seconds to acquire high-resolution (better than 10 ÎĽm) results. This temporal expense creates a high inefficiency in sample processing and throughput. For example, in a high-resolution nano-DESI study, a single mouse uterine tissue section (2.5 mm by 1.7 mm) had an acquisition time of ~4 hours to acquire 104,400 pixels. Anywhere from ~25-30% of those pixels were outside the actual tissue, and a further portion of those locations lacked relevant information. An existing method, a Supervised Learning Approach for Dynamic Sampling (SLADS), utilizes information obtained during an active scan to infer, using a least-squares regression, regions of interest that most likely contain meaningful information, and a computationally inexpensive weighted mean interpolation to perform sparse sample reconstruction. This approach could potentially be used to significantly improve throughput in this and other biological tissue scanning applications. However, existing SLADS implementations were neither designed nor optimized for leveraging or handling the 3rd dimension in MSI of molecular spectra. Further, integrating more recent advances in machine learning since the last SLADS publication issuance, such as Convolutional Neural Network (CNN) architectures, offers additional performance gains. The objective of this research is the updating, re-design, and optimization of the SLADS methodology, to form a Deep Learning Approach for Dynamic Sampling (DLADS) for high-resolution biological tissues and integration with nano-DESI MSI instrumentation
Clarifying the conception of consciousness: Lonergan, Chalmers, and confounded epistemology
Applying Bernard Lonergan's (1957/1992, 1972) analysis of intentional consciousness and its concomitant epistemology, this paper highlights epistemological confusion in contemporary consciousness studies as exemplified mostly in David Chalmers's (1996) position.
In ideal types, a first section outlines two epistemologies-sensate-modeled and intelligence-based-whose difference significantly explains the different positions. In subsequent sections, this paper documents the sensate-modeled epistemology in Chalmers's position and consciousness studies in general. Tellingly, this model of knowing is at odds with the formal-operational theorizing in twentieth-century science.
This paper then links this epistemology with functionalism and its focus on descriptive efficient causality in external behaviors and its oversight of explanatory formal causality; highlights the theoretical incoherence of the understanding of science in the functionalist approach; connects it with the construal of consciousness as primarily intentional (i.e., directed toward an object) to the neglect of consciousness as conscious (i.e., constituted by a non-objectified self-presence); and relates this outcome to the reduction of human consciousness to animal-like perception and mechanistic interactions.
A brief conclusion summarizes these multiple, subtle, and interconnected considerations and suggests how only an intellectual epistemology would be adequate to the intellectual nature of human consciousness and the world of meaning, not of mere bodies, in which humans exist
Orbital parameters and evolutionary status of the highly-peculiar binary system HD 66051
The spectroscopic binary system HD 66051 (V414 Pup) consists of a highlypeculiar CP3 (HgMn) star and an A-type component. It also shows out-of-eclipsevariability that is due to chemical spots. This combination allows thederivation of tight constraints for the testing of time-dependent diffusionmodels. We analysed radial velocity and photometric data using two differentmethods to determine astrophysical parameters and the orbit of the system.Appropriate isochrones were used to derive the age of the system. The orbitalsolution and the estimates from the isochrones are in excellent agreement withthe estimates from a prior spectroscopic study. The system is very close to thezero-age main sequence and younger than 120 Myr. HD 66051 is a most importantspectroscopic binary system that can be used to test the predictions of thediffusion theory explaining the peculiar surface abundances of CP3 stars.Fil: Paunzen, E.. Masaryk University; RepĂşblica ChecaFil: Fedurco, M.. Masaryk University; RepĂşblica ChecaFil: Helminiak, K.G.. Masaryk University; RepĂşblica ChecaFil: Pintado, Olga Ines. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Tucumán. Instituto Superior de CorrelaciĂłn GeolĂłgica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de GeologĂa. Cátedra GeologĂa Estructural. Instituto Superior de CorrelaciĂłn GeolĂłgica; Argentin
A Comprehensive Theory of Spirituality: Humanistic, Theist, and Theotic
Especially among the Abrahamic religions, quite regularly spirituality implies a relationship with God or else some other supposed “sacred” entities or forces. This starting point precludes a fully psychological explanation of spirituality since appeal to God exceeds the methodology of the social or human sciences: Psychology is not theology. In contrast, a traditional Christian axion holds that "grace builds on nature." Accordingly, recognize that a dimension of the human mind itself—consciousness or human spirit—is first and foremost the source and object of spiritual experiences. Then the natural becomes fundamental, theoretically the essential, and at its roots spirituality lies within the competence of human study, and religious accounts are further elaborations. This proposition is the thesis of this article. Following the trenchant analyses of Bernard Lonergan, this account recognizes human consciousness or spirit as a dynamic dimension of the mind, self-present, out-going, self-transcending, open-ended, geared to reality, and normative: These requisites inherent in consciousness orient a person toward the true and the good. Then personal integration and spiritual growth coincide—in this way: Psychotherapeutic healing frees the spirit to increasingly take the lead and guide one’s living, constituting one as “a spiritual person.” The specification of consciousness/spirit contrasts with other mental content—emotions, memory, imagery—and suggests a tripartite human model (organism, psyche, and consciousness) in place of the standard bipartite model (body and mind). Such a naturalistic starting point easily supports religious elaboration, seeing God as Creator (theology) and envisioning union with God (theotics). This theory foresees the collaboration of the world's religions in acknowledging a common spiritual foundation for themselves and for our pluralistic secular society
Construction and Characterization of a Single Stage Dual Diaphragm Gas Gun
In the interest of studying the propagation of shock waves, this work sets out to design, construct, and characterize a pneumatic accelerator that performs high-velocity flyer plate impact tests. A single stage gas gun with a dual diaphragm breach allows for a non-volatile, reliable experimental testing platform for shock phenomena. This remotely operated gas gun utilizes compressed nitrogen to launch projectiles down a 14 foot long, 2 inch diameter bore barrel, which subsequently impacts a target material of interest. A dual diaphragm firing mechanism allows the 4.5 liter breech to reach a total pressure differential of 10ksi before accelerating projectiles to velocities as high as 1,000 m/s (1570-2240 mph). The projectile’s velocity is measured using a series of break pin circuits. The target response can be measured with Photon Doppler Velocimetry (PDV) and/or stress gauge system. A vacuum system eliminates the need for pressure relief in front of the projectile, while additionally allowing the system to remain closed over the entire firing cycle. Characterization of the system will allow for projectile speed to be estimated prior to launching based on initial breach pressure
Acetylene terminated matrix resins
The synthesis of resins with terminal acetylene groups has provided a promising technology to yield high performance structural materials. Because these resins cure through an addition reaction, no volatile by-products are produced during the processing. The cured products have high thermal stability and good properties retention after exposure to humidity. Resins with a wide variety of different chemical structures between the terminal acetylene groups are synthesized and their mechanical properties studied. The ability of the acetylene cured polymers to give good mechanical properties is demonstrated by the resins with quinoxaline structures. Processibility of these resins can be manipulated by varying the chain length between the acetylene groups or by blending in different amounts of reactive deluents. Processing conditions similar to the state-of-the-art epoxy can be attained by using backbone structures like ether-sulfone or bis-phenol-A. The wide range of mechanical properties and processing conditions attainable by this class of resins should allow them to be used in a wide variety of applications
The multiplicity of massive stars in the Orion Nebula cluster as seen with long-baseline interferometry
The characterization of multiple stellar systems is an important ingredient
for testing current star formation models. Stars are more often found in
multiple systems, the more massive they are. A complete knowledge of the
multiplicity of high-mass stars over the full range of orbit separations is
thus essential to understand their still debated formation process.
Observations of the Orion Nebula Cluster can help to answer the question about
the origin and evolution of multiple stars. Earlier studies provide a good
knowledge about the multiplicity of the stars at very small (spectroscopic) and
large separations (AO, speckle) and thus make the ONC a good target for such a
project. We used the NIR interferometric instrument AMBER at VLTI to observe a
sample of bright stars in the ONC. We complement our data set by archival NACO
observations of \theta 1 Ori A to obtain more information about the orbit of
the close visual companion. Our observations resolve the known multiple systems
\theta 1 Ori C and \theta 1 Ori A and provide new orbit points, which confirm
the predicted orbit and the determined stellar parameters for \theta 1 Ori C.
Combining AMBER and NACO data for \theta 1 Ori A we were able to follow the
motion of the companion from 2003 to 2011. We furthermore find hints for a
companion around \theta 1 Ori D and a previously unknown companion to NU Ori.
With a probability of ~90% we can exclude further companions with masses of > 3
Msun around our sample stars for separations between ~2 mas and ~110 mas. We
conclude that the companion around \theta 1 Ori A is most likely physically
related to the primary star. The newly discovered possible companions further
increase the multiplicity in the ONC. For our sample of two O and three B-type
stars we find on average 2.5 known companions per primary, which is around five
times more than for low-mass stars.Comment: accepted by A&
Failure of Thick, Low Density Air Plasma Sprayed Thermal Barrier Coatings
This research was directed at developing fundamental understandings of the variables that influence the performance of air plasma sprayed (APS) yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBC). Focus was placed on understanding how and why each variable influenced the performance of the TBC system along with how the individual variables interacted with one another.
It includes research on the effect of surface roughness of NiCoCrAlY bond coats deposited by argon-shrouded plasma spraying, the interdiffusion behavior of bond coats coupled to commercial superalloys, and the microstructural and compositional control of APS topcoats to maximize the coating thicknesses that can be applied without spallation. The specimens used for this research were prepared by Praxair Surface Technologies and have been evaluated using cyclic oxidation and thermal shock tests.
TBC performance was sensitive to bond coat roughness with the rougher bond coats having improved cyclic performance than the smoother bond coats. The explanation being the rough bond coat surface hindered the propagation of the delamination cracks.
The failure mechanisms of the APS coatings were found to depend on a combination of the topcoat thickness, topcoat microstructure and the coefficient of thermal expansion (CTE) mismatch between the superalloy and topcoat. Thinner topcoats tended to fail at the topcoat/TGO interface due to bond coat oxidation whereas thicker topcoats failed within the topcoat due to the strain energy release rate of the thicker coating exceeding the fracture strength of the topcoat.
Properties of free-standing high and conventional purity YSZ topcoats of both a low-density (LD) and dense-vertically fissure (DVF) microstructures were evaluated. The densification rate and phase evolution were sensitive to the YSZ purity and the starting microstructure. Increasing the impurity content resulted in enhanced sintering and phase decomposition rates, with the exception of the conventional-purity DVF which exhibited a density decrease during sintering. A combination of the DVF and LD topcoat microstructures (dual TBC) resulted in significant increase in cyclic durability. A 1275 ÎĽm thick dual TBC coating was found to have a comparable furnace cyclic life to that of a 100 ÎĽm LD TBC
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Session A3- Removing barriers at road crossings using stream simulation techniques in the northeast United States
Anthropogenic fragmentation of river and stream corridors is often identified with remnant dams throughout the Northeast; however, stream-road crossings also play a significant role. Culverts that block passage of aquatic and terrestrial organisms are surprisingly common- underscoring the importance of recent efforts to identify and retrofit crossings. The Massachusetts River and Stream Crossing Standards utilize a stream simulation approach for road crossing replacement that strives to restore continuity and facilitate movement of all aquatic organisms, including terrestrial species dependent on the river\u27s edge. In western Massachusetts, a perched culvert at the confluence of Mitchell Brook and West Brook, gravel bed streams in the Connecticut River watershed, was targeted for retrofit to reconnect habitat for resident native brook trout. The Nature Conservancy and American Rivers, in partnership with the Conte Anadromous Fish Research Center for the West Brook Stream Continuity study, contracted Princeton Hydro LLC to design the replacement of the perched culvert with a simulated stream channel. Conte and The Nature Conservancy have accumulated several years of data on the movement and health of resident trout populations in the West Brook watershed that will be utilized to evaluate the performance of the proposed replacement. This replacement is an important component to the long term study to better understand stream continuity for resident trout populations in the watershed and stream connectivity and barrier removal in the region. The successful completion of this culvert replacement will allow the partners a firsthand chance to analyze the success of culvert replacements using the Massachusetts River and Stream Crossing Standards and will act as a model for future projects that look to defragment highly impacted streams throughout the Northeast
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