241 research outputs found
Float-polishing process and analysis of float-polished quartz
A fluid-mechanical model is developed for the float-polishing process. In this model laminar flow between the sample and the lap results in pressure gradients at the grooves that support the sample on a fluid layer. The laminar fluid motion also produces supersmooth, damage-free surfaces. Quartz substrates for applications in high-stress environments were float polished, and their surfaces were analyzed by optical scatterometry, photoacoustic spectroscopy, and atomic force microscopy. The removal of 100 µm of material by a lapping-polishing process, with final float polishing, left low levels of subsurface damage, with a surface roughness of approximately 0.2-nm rms
Decision support combining machine learning, knowledge representation and case-based reasoning
Knowledge and knowledge work are essential for the success of companies nowadays.
Decisions are based on knowledge and better knowledge leads to more informed decisions.
Therefore, the management of knowledge and support of decision making has increasingly
become a source of competitive advantage for organizations. The current research uses a
design science research approach (DSR) with the aim to improve the decision making of a
knowledge intensive process such as the student admission process, which is done manually
until now. In the awareness phase of the DSR process, the case study research method is applied
to analyze the decision making and the knowledge that is needed to derive the decisions. Based
on the analysis of the application scenario, suitable methods to support decision making were
identified. The resulting system design is based on a combination of Case-Based Reasoning
(CBR) and Machine Learning (ML). The proposed system design and prototype has been
validated using triangulation evaluation, to assess the impact of the proposed system on the
application scenario. The evaluation revealed that the additional hints from CBR and ML can
assist the deans of the study program to improve the knowledge management and increase the
quality, transparency and consistency of the decision-making process in the student application
process. Furthermore, the proposed approach fosters the exchange of knowledge among the
different process participants involved and codifies previously tacit knowledge to some extent
and provides relevant externalized knowledge to decision makers at the required moment. The
designed prototype showcases how ML and CBR methodologies can be combined to support
decision making in knowledge intensive processes and finally concludes with potential
recommendations for future research.http://ceur-ws.orgam2022Informatic
The effect of health on urban-settlement intention of rural-urban migrants in China
Previous studies have not paid enough attention to the effect of health
on urban-settlement intention of rural-urban migrants in China. Using
survey data from the Rural Urban Migration in China project, this
article examines how self-rated physical and mental health influence
rural-urban migrants’ intention to settle down in cities. First, the
results show that both self-rated physical and mental health are
significant factors influencing the migrants’ intention to permanently
move to cities. Second, the effect of physical health on rural-urban
migrants’ intentions to permanently reside in cities can be moderated by
their length of urban residence. Third, the impact of health on
rural-urban migrants’ urban-settlement intention shows no generational
differences. According to the research findings, this paper discusses
how urban-settlement intention of rural-urban migrants based on health
selection might impair urbanization, exacerbate health disparity between
the rural and urban areas, and aggravate the burden on healthcare
system in rural areas of China in the long run.</div
Skunk River Review Autumn 1994, vol 6
https://openspace.dmacc.edu/skunkriver/1009/thumbnail.jp
Presence of Systemic Amyloidosis in Mice with Partial Deficiency in Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) in Aging
Pituitary adenylate cyclase-activating polypeptide (PACAP), a neuropeptide with widespread expression and general cytoprotective effects, is also involved in aging. Previously, we observed accelerated systemic senile amyloidosis in PACAP knockout (KO) mice. As mice partially lacking PACAP (heterozygous-HZ) show variable symptoms, here we investigated whether HZ mice have accelerated aging, completed with observations in PAC1 receptor KO mice. As we have limited data on qualitative or quantitative changes in the blood of PACAP-deficient mice, we investigated whether these changes could be in the background of the amyloidosis. Routine histological staining was used to examine amyloid deposits, rated on a severity scale 0–3. Blood was collected from PACAP wild type/HZ mice for complete blood analysis. In contrast to receptor KO mice showing no amyloidosis, histopathological analysis revealed severe deposits in PACAP HZ mice, with kidney, spleen, skin, and intestines being most affected. Increased cholesterol, lipoprotein levels, and differences in several blood count parameters were found in HZ mice. In summary, amyloidosis also develops in partial absence of PACAP, in contrast to the lack of its PAC1 receptor. In addition to the earlier identified inflammatory and degenerative disturbances, the alteration in lipid metabolism and bone marrow activity can also be additional factors leading to systemic degenerative processes
Paraconsistent Reasoning for OWL 2
A four-valued description logic has been proposed to reason with description logic based inconsistent knowledge bases. This approach has a distinct advantage that it can be implemented by invoking classical reasoners to keep the same complexity as under the classical semantics. However, this approach has so far only been studied for the basid description logic ALC. In this paper, we further study how to extend the four-valued semantics to the more expressive description logic SROIQ which underlies the forthcoming revision of the Web Ontology Language, OWL 2, and also investigate how it fares when adapated to tractable description logics including EL++, DL-Lite, and Horn-DLs. We define the four-valued semantics along the same lines as for ALC and show that we can retain most of the desired properties
Epigenetic Differences in Cortical Neurons from a Pair of Monozygotic Twins Discordant for Alzheimer's Disease
DNA methylation [1], [2] is capable of modulating coordinate expression of large numbers of genes across many different pathways, and may therefore warrant investigation for their potential role between genes and disease phenotype. In a rare set of monozygotic twins discordant for Alzheimer's disease (AD), significantly reduced levels of DNA methylation were observed in temporal neocortex neuronal nuclei of the AD twin. These findings are consistent with the hypothesis that epigenetic mechanisms may mediate at the molecular level the effects of life events on AD risk, and provide, for the first time, a potential explanation for AD discordance despite genetic similarities
Gastrin-Releasing Peptide Signaling Plays a Limited and Subtle Role in Amygdala Physiology and Aversive Memory
Links between synaptic plasticity in the lateral amygdala (LA) and Pavlovian fear learning are well established. Neuropeptides including gastrin-releasing peptide (GRP) can modulate LA function. GRP increases inhibition in the LA and mice lacking the GRP receptor (GRPR KO) show more pronounced and persistent fear after single-trial associative learning. Here, we confirmed these initial findings and examined whether they extrapolate to more aspects of amygdala physiology and to other forms of aversive associative learning. GRP application in brain slices from wildtype but not GRPR KO mice increased spontaneous inhibitory activity in LA pyramidal neurons. In amygdala slices from GRPR KO mice, GRP did not increase inhibitory activity. In comparison to wildtype, short- but not long-term plasticity was increased in the cortico-lateral amygdala (LA) pathway of GRPR KO amygdala slices, whereas no changes were detected in the thalamo-LA pathway. In addition, GRPR KO mice showed enhanced fear evoked by single-trial conditioning and reduced spontaneous firing of neurons in the central nucleus of the amygdala (CeA). Altogether, these results are consistent with a potentially important modulatory role of GRP/GRPR signaling in the amygdala. However, administration of GRP or the GRPR antagonist (D-Phe6, Leu-NHEt13, des-Met14)-Bombesin (6–14) did not affect amygdala LTP in brain slices, nor did they affect the expression of conditioned fear following intra-amygdala administration. GRPR KO mice also failed to show differences in fear expression and extinction after multiple-trial fear conditioning, and there were no differences in conditioned taste aversion or gustatory neophobia. Collectively, our data indicate that GRP/GRPR signaling modulates amygdala physiology in a paradigm-specific fashion that likely is insufficient to generate therapeutic effects across amygdala-dependent disorders
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