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Collation Model for Ms. Codex 1076: [Prolegomena in Aristotelem] Volume 1
Get PDFLecture notes in Latin based on the works of Aristotle, notably the theories on universals, material, form, substance, astronomy, and geometry from the Physics, and logic and rhetoric from the Metaphysics, with tables of contents included at the end of each volume. Written in Italy in 1598. This is the model for Volume 1.https://repository.upenn.edu/sims_models/1097/thumbnail.jp
The Effect Of Different Cleaning Agents On The Bond Strength Of Contaminated Zirconia
No full textObjectives: This study evaluated the influence of saliva contamination and the effect of several cleaning methods, on the resin bond durability to zirconia. Shear tests were performed to assess the shear bond strength of specimens after 24 h of storage or after thermocycling as an aging method.
Methods: One hundred KATANA Zirconia STML (n=20) specimens were sectioned and sintered in an induction furnace (CEREC SpeedFire, Dentsply Sirona, Germany). Specimen surfaces were ground finished with 800 grit silicon carbide abrasive with cooling water and cleaned with ultrasonication in alcohol. Specimens were air-particle abraded with 50 μm aluminum oxide at 2.8 bar pressure. All samples were equally divided into 5 groups (n = 20) according to the cleaning method. Groups were contaminated with saliva, and subjected to different cleaning protocols, namely: APC, Katana Cleaner (KC), Ivoclean(IC) and Zirclean(ZC). Cylindrical composite resin specimens (2.1 mm in diameter, 3 mm in height) were bonded to the zirconia samples with dual-cure multi-step composite resin cement Panavia V5 following manufacturers’ instructions. A load of 1000 g was applied to the composite cylinders during bonding in an alignment apparatus, then light cured for 80 s. Samples were stored in distilled water at 37° C for 48 h, then subjected to 10,000 thermal cycles. Shear bond strength was determined using a universal testing machine at a crosshead speed of 0.5 mm/min expressed in MPa. The fractured surfaces of specimens were inspected with a stereo microscope and classified as adhesive, cohesive, or mixed failures. Paired t-test and pairwise comparisons (Posthoc bonferroni test) with α=0.05 were applied for statistical analysis.
Results: Shear bond strength values [MPa] under normal conditions (NC) were for Control 22.2 (10.26 SD), APC 52.78 (2.76 SD), KC 33.45 (13.59 SD), IC 34.66 (9.97 SD), and ZC 32.77 (14.53 SD). Shear bond strength values [MPa] under thermocycling (TC) conditions were for Control 6.51 (2.44 SD), APC 18.97 (8.67 SD), KC 17.11 (9.60 SD), IC 16.26 (3.62 SD), and ZC 15.13 (2.90 SD). Intragroup analysis using paired t-test revealed statistically significant differences in shear bond strength in every group between normal condition (NC) and thermocycling conditions (TC) (p\u3c0.05). Intergroup analysis using Bonferroni Post-hoc test revealed statistically significant difference in shear bond strength among the tested groups (p\u3e0.5) when compared to the control group with group 2-APC having significantly higher shear bond strength when compared to the other test groups (p\u3c0.05).
Conclusions:
According to the results of this in vitro study, Zirconia ceramics’ cleaning protocol must be considered after exposure to saliva during intraoral try-in procedures. Application of zirconia cleaning agents to the contaminated zirconia surfaces is as effective as mechanical surface abrasion and offers a simple step-by-step cleaning method for restoring zirconia surfaces after contamination
Preliminary Analysis of Transcriptomic Variations in Esrp1/Sox2 Double Transgenic Mouse Embryo Facial Prominences in Search of Esrp1 Targets Responsible for Cleft Lip and/or Palate Pathogenesis
Get PDFCleft lip and/or palate (CL/P) is a highly prevalent craniofacial deformation worldwide, that is challenging to treat. Despite the series of reconstructive surgeries, orthodontic treatments, and functional rehabilitation therapies, patients can not fully recover from the esthetic and functional defect they were born with. A paradigm-shift in treatment approach is needed to lift the medical, psychosocial, and financial burdens from the patients and their families, one that would intercept the malformation in utero and recapitulate normal development of the lip and the palate before birth. A necessary first step towards this goal is to decipher the intricate molecular mechanisms underlying CL/P pathogenesis. We used a novel double transgenic mouse model Esrp1-/-;Sox2+/- and RNA-sequencing technology to search for target genes responsible for CL/P. The ablation of Esrp1 results in orofacial clefting in mouse embryos, but Sox2 haploinsufficiency in Esrp1-/- mouse rescues the CL/P phenotype by restoring normal development of the face. The analysis of the transcriptomic variations between Wild Type, Esrp1-/- and Esrp1-/-;Sox2+/- mice revealed that numerous genes were differentially expressed in the ectoderm and mesenchyme of the facial prominences at a critical stage for fusion. Among the genes that were either normalized or compensated by Sox2 haploinsufficiency in the Rescue model, we identified genes from known signaling pathways like Bmp4 and key epithelial-mesenchymal transition genes such as Snai1, Twist1, and Zeb1. This preliminary study lays the groundwork for promising treatment opportunities for orofacial clefting
Sociolinguistic Factors of Mandarin-English Codeswitching: Language Attitudes, Age, and Other Factors Used for Computational Modeling
Get PDFThis paper explores the sociolinguistic predictors of Mandarin-English codeswitching, and also tests such patterns against current syntactic constraints of codeswitching. By doing so, I demonstrate the value of incorporating sociolinguistic factors as predictors into computational models of codeswitching, explored in a companion paper (Yi 2022). The study presented here draws from novel data collected from 12 Mandarin-English bilingual speakers from Grand Rapids, Michigan. These speakers come from two generations, correlated with their age and immigration history. Speakers participated in sociolinguistic interviews that were designed to elicit codeswitching in narrative-style responses on a variety of topics, including family, school, and culture. Participants also answered metalinguistic questions about their own language practices and attitudes and completed a written Language History Questionnaire (LHQ) (Li et al. 2020), which asked for self-evaluations of language habits (proficiency, immersion, and dominance in the two languages). LHQ responses were then quantified into “scores” that served as sociolinguistic predictors for the companion paper (Yi 2022). Patterns found in this novel Mandarin-English data frequently, and potentially systematically, violate many of the currently proposed syntactic constraints on codeswitching (which mainly come from research on Spanish-English bilinguals), implying that the constraints may not be universal, and that new avenues should be considered for understanding the morphosyntax of bilingual codeswitching
The Effects Of Platelet Signaling Inhibitors On Clot Development Under Flow
Get PDFGPVI is the first responder towards collagen surface and therefore, the role of GPVI in facilitating primary platelet deposition is well studied and unquestionable. However, whether it plays a part in secondary platelet deposition by binding with fibrin, thus facilitating further platelet activation remains a question. Depending on the experiment method and rationale behind it, different results and conclusion could be achieved, thus it calls for a method that could better recapitulate human blood system under in vitro setting with appropriate methods to inhibit GPVI.Indirect method incorporates Syk and Src family kinases (SFK) inhibitors; these molecules interfere with signaling from GPVI, α2β1, αIIbβ3, and GPIb-IX-V to reduce thrombotic risk or induce bleeding episodes. Collagen-mediated clustering of platelet GPVI results in phosphorylation of SFKs such as Lyn and Fyn, and active Lyn is constitutively bound to GPVI to allow rapid signaling. During clotting under flow, the generation of fibrin can have diverse influences on platelet signaling by sequestering thrombin and potentially activating GPVI signaling within the clot interior. These inhibitors tackle the thrombus formation at earlier stages since the platelets reach the activation surface. Direct inhibition of GPVI, which involves using an artificial anti-GPVI fragment, was used to avoid undesirable inhibition and compare the difference between inhibition of subsequent pathways. Using microfluidics, the effects of these inhibitors can be explored under defined hemodynamic flows and procoagulant surface triggers. Additionally, the drug may be present in the blood at desired time of clotting by perfusion switching to drug-treated blood. This experimental design allows exploration of platelet response at different stages of clotting through the measurement of drug potency to modulate clotting on different procoagulant surface conditions, interactions between various coagulation factors in plasma, and the kinetics of several competitive reactions to facilitate platelet recruitment, granule release and fibrin formation
Effect Of Probe Characteristics And Hydrogel Structure On Single Nanoparticle Dynamics
No full textHydrogels are ubiquitous synthetic and biological polymeric networks, prominent in a range of industrial applications and commonly found in the natural world. The applications of hydrogels to solve global challenges including nanoscale filtration to create potable water and controlled drug delivery for increasingly advanced medical interventions requires an understanding the dynamics of nanoparticles and other molecules within hydrogel networks. For this dissertation, I studied nanoparticle dynamics in synthetic hydrogels using single particle tracking. By tuning both the hydrogel nanostructure and nanoparticle probe characteristics, I investigated how the addition of immobile nanoparticles in nanocomposite hydrogels, probe shape and size, and the mesh size of the network affect the dynamics of individual nanoparticles. Single particle tracking allowed for the visualization of single nanoparticle trajectories, which were then analyzed to yield quantitative information including the mean squared displacement, the van Hove distribution function, and the non-Gaussian parameter. In silica-polyacrylamide hydrogel nanocomposites, the interactions between the poly(ethylene glycol) (PEG) functionalized nanoparticles and the static silica nanoparticles dominated dynamics, as the presence of interactions could be tuned by changing the pH, affecting nanoprobe mobility. During the gelation of a nearly homogeneous tetra-PEG hydrogel with a final mesh size similar to the probe diameters, nanorods of comparable minor diameters to their spherical counterparts exhibited enhanced dynamics as the hydrogel network formed. This suggests that nanorods under increasing confinement exhibit distinct mechanisms of mobility, exhibited by the presence of caging to mobile transitions. Network defects also have a pronounced effect on probe dynamics, though the extent is dependent on the nanoparticle size compared to the length scale of the defects as measured in defective tetra-PEG hydrogels. For example, smaller probes exhibit increased dynamics due to a larger percentage of mobile particles as they are more sensitive to small perturbations in the network. Identifying factors that impact nanoparticle dynamics in swollen networks at the nanoscale, including probe-particle interactions, probe shape and size, and network defects will inform the thoughtful design of hydrogels for applications such as drug delivery systems and filtration membranes
Sublinear Algorithm And Lower Bound For Combinatorial Problems
Get PDFAs the scale of the problems we want to solve in real life becomes larger, the input sizes of the problems we want to solve could be much larger than the memory of a single computer. In these cases, the classical algorithms may no longer be feasible options, even when they run in linear time and linear space, as the input size is too large.
In this thesis, we study various combinatorial problems in different computation models that process large input sizes using limited resources. In particular, we consider the query model, streaming model, and massively parallel computation model. In addition, we also study the tradeoffs between the adaptivity and performance of algorithms in these models.We first consider two graph problems, vertex coloring problem and metric traveling salesman problem (TSP). The main results are structure results for these problems, which give frameworks for achieving sublinear algorithms of these problems in different models. We also show that the sublinear algorithms for (∆ + 1)-coloring problem are tight. We then consider the graph sparsification problem, which is an important technique for designing sublinear algorithms. We give proof of the existence of a linear size hypergraph cut sparsifier, along with a polynomial algorithm that calculates one. We also consider sublinear algorithms for this problem in the streaming and query models. Finally, we study the round complexity of submodular function minimization (SFM). In particular, we give a polynomial lower bound on the number of rounds we need to compute s − t max flow - a special case of SFM - in the streaming model. We also prove a polynomial lower bound on the number of rounds we need to solve the general SFM problem in polynomial queries
Time\u27s Deep Rhythms: Models, Mechanisms, And Narratives In Historical Explanation
Get PDFMy dissertation is focused on the question of how it is that explanation works in the “historical sciences” (i.e. scientific disciplines dealing with questions of the deep past). I survey the extant literature in order to develop a loose taxonomy of approaches as developed up to this point. While there are some deep differences in these approaches, at least one common theme emerges: the overwhelming majority of philosophical (and scientific) work on historical narrative explanation understands such explanations to be focused on highly particularized explanatory targets. That is, narrative explanations are understood to involve the reconstruction of highly particular causal histories that are supposed to explain the generation of a highly particular explananda of interest. The majority of the literature, then, has (wittingly or unwittingly) upheld the distinction between the so-called nomothetic sciences (e.g. physics) and the idiographic sciences (e.g. paleontology). The nomothetic sciences, it is supposed, offer explanations in terms of laws and regularities, whereas the idiographic sciences explain by “depicting” narrative structures. Further, the idiographic sciences, insofar as they explain, supposedly do so in a way that is impoverished relative to the nomothetic sciences. I thinkthis distinction rests on several mistakes, which I attempt to remedy in my dissertation
Private Federated Analytics At Scale
Get PDFCollecting distributed data from millions of individuals for the purpose of analytics is a common scenario – from Apple collecting typed words and emojis to improve its keyboard suggestions, to Google collecting location data to see how busy restaurants and businesses are. This data is often sensitive, and can be overly revealing about the individuals and communities whose data is being analyzed en masse. Differential privacy has become the gold-standard method to give strong individual privacy guarantees while releasing aggregate statistics about sensitive data. However, the process of computing such statistics can itself be a privacy risk. For instance, a simple approach would be to collect all the raw data at a single central entity, which then computes and releases the statistics. This entity then has to be trusted to not abuse the raw data; in practice, it can be difficult to find an entity with the requisite level of trust.
In this thesis, we describe a new approach that uses cryptographic techniques to collect data privately and safely, without placing trust in any party. Although the natural candidates, such as secure multiparty computation (MPC) and fully homomorphic encryption (FHE) do not scale to millions of parties on their own, our key insight is that there are ways to refactor computations in such a way that they can be done using simpler techniques that do scale, such as additively homomorphic encryption. Our solution restructures centralized computations into distributed protocols that can be executed efficiently at scale.
The systems we design based on this approach can support billions of participants and can handle a variety of real queries from the literature, including machine learning tasks, Pregel-style graph queries, and queries over large categorical data. We automate the distributed refactoring so that analysts can write the query as if the data were centralized without understanding how the rewriting works, and we protect against malicious parties who aim to poison or bias the results
Shared Songs, Sonic Memory: Groundwater For Voice, Chamber Ensemble, And Electronics And Essays On 13th-Century Song
No full textThis dissertation consists of two parts: the score for a new musical work entitled Groundwater, and three essays on 13th-century vocal repertoires. These two different approaches—one creative and one scholarly—address related issues in compositional process with preexistent materials, sonic signification and recycling, and visual aspects of music notation. Groundwater is an evening-length work scored for voice and chamber ensemble with live electronics and video projections. It treats groundwater as a metaphor for memory and sets up feedback loops between sonic processes and their visual effects, often through asking performers to interpret these visuals as notation. “Mapping Shared Tunes: Pitch-based Logic in Late Medieval Refrain Citation” is a data-driven, corpus-wide review of intertextual refrains in the long 13th century that focuses on the compositional integration of refrains used across multiple works. I demonstrate that semitone-preserving transposition, especially by perfect fourth and fifth, was a core procedure for medieval composers working with refrains. “Common Tunes, Varied Songs: IN SECULUM Motets in the Sixth Fascicle of the Montpellier Codex” analyzes a group of motets on IN SECULUM—the most common 13th-century motet tenor. These motets display an unusually wide range of rhythmic treatments of the tenor and integrations of intertextual refrains in the upper voices. I argue that the “stockness” of the IN SECULUM tenor facilitated this compositional virtuosity and that these motets provided a key structure for the fascicle as well as an important connection to the rest of the manuscript. Finally, “Auralizing the Love Triangle: Polyphonic Rondeau Refrains in Renart le nouvel” examines a set of intertextual refrains shared between the satirical romance Renart le nouvel and polyphonic rondeaux from the 13th century. I argue that these refrains are direct citations from the rondeaux and that their use forms a deliberate citational strategy. By cuing the three voices of polyphonic rondeaux and drawing on characteristics of their texture and voice-leading, Renart’s compilers effectively auralized scenes of love triangles and adultery for medieval readers