Physical Sciences and Mathematics Commons^™

Unravelling The Correlation Of Electronic Structure And Carrier Dynamics In Cuins2 Nanoparticles, Wenhui Hu, John Ludwig, Brian Pattengale, Sizhuo Yang, Cunming Liu, Xiaobing Zuo, Xiaoyi Zhang, Jier Huang

Chemistry Faculty Research and Publications

In this work, we report the direct correlation of photoinduced carrier dynamics and electronic structure of CuInS₂ (CIS) nanoparticles (NPs) using the combination of multiple spectroscopic techniques including steady-state X-ray absorption spectroscopy (XAS), optical transient absorption (OTA), and X-ray transient (XTA) absorption spectroscopy. XAS results show that CIS NPs contain a large amount of surface Cu atoms with ≪four-coordination, which is more severe in CIS NPs with shorter nucleation times, indicating the presence of more Cu defect states in CIS NPs with smaller size particles. Using the combination of OTA and XTA spectroscopy, we show that electrons are trapped …

Unravelling The Correlation Of Electronic Structure And Carrier Dynamics In Cuins2 Nanoparticles, Wenhui Hu, John Ludwig, Brian Pattengale, Sizhuo Yang, Cunming Liu, Xiaobing Zuo, Xiaoyi Zhang, Jier Huang

Chemistry Faculty Research and Publications

In this work, we report the direct correlation of photoinduced carrier dynamics and electronic structure of CuInS₂ (CIS) nanoparticles (NPs) using the combination of multiple spectroscopic techniques including steady-state X-ray absorption spectroscopy (XAS), optical transient absorption (OTA), and X-ray transient (XTA) absorption spectroscopy. XAS results show that CIS NPs contain a large amount of surface Cu atoms with ≪four-coordination, which is more severe in CIS NPs with shorter nucleation times, indicating the presence of more Cu defect states in CIS NPs with smaller size particles. Using the combination of OTA and XTA spectroscopy, we show that electrons are trapped …

Search For High-Energy Neutrinos From Binary Neutron Star Merger Gw170817 With Antares, Icecube, And The Pierre Auger Observatory, Antares Collaboration, The Icecube Collaboration, The Pierre Auger Collaboration, Ligo Scientific Collaboration, Virgo Collaboration, Karen Andeen

Physics Faculty Research and Publications

The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merger of this binary was also recorded by the FermiGamma-ray Burst Monitor (Fermi-GBM), and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory(INTEGRAL), indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the GeV–EeV energy range using the Antares, IceCube, and Pierre Auger Observatories. …

Measurement Of The Multi-Tev Neutrino Interaction Cross-Section With Icecube Using Earth Absorption, Karen Andeen, The Icecube Collaboration

Physics Faculty Research and Publications

Neutrinos interact only very weakly, so they are extremely penetrating. The theoretical neutrino–nucleon interaction cross-section, however, increases with increasing neutrino energy, and neutrinos with energies above 40 teraelectronvolts (TeV) are expected to be absorbed as they pass through the Earth. Experimentally, the cross-section has been determined only at the relatively low energies (below 0.4 TeV) that are available at neutrino beams from accelerators^1,2. Here we report a measurement of neutrino absorption by the Earth using a sample of 10,784 energetic upward-going neutrino-induced muons. The flux of high-energy neutrinos transiting long paths through the Earth is attenuated compared to …

Mechanistic Probes Of Zeolitic Imidazolate Framework For Photocatalytic Application, Brian Pattengale, Sizhuo Yang, Sungsik Lee, Jier Huang

Chemistry Faculty Research and Publications

In this work, we report a zeolitic imidazolate framework (ZIF-67) with remarkable activity in the hydrogen evolution reaction (HER): 40 500 μmol H₂/g of metal organic framework (MOF). This is, to the best of our knowledge, the highest activity achieved by any MOF system. This result necessitated assessment of the atomic-scale mechanistic function of ZIF-67 in HER, using advanced spectroscopy techniques, including time-resolved optical (OTA) and in situ X-ray-absorption (XAS) spectroscopy. Through the correlation of the OTA results with the catalytic performance, we demonstrated that the electron transfer (ET) pathway, rather than the energy transfer (ENT) pathway, between …

Mito-Apocynin Prevents Mitochondrial Dysfunction, Microglial Activation, Oxidative Damage, And Progressive Neurodegeneration In Mitopark Transgenic Mice, Monica Langley, Anamitra Ghosh, Adhithiya Charli, Souvarish Sarkar, Muhammet Ay, Jie Luo, Jacek Zielonka, Timothy Brenza, Brian Bennett, Huajun Jin, Shivani Ghaisas, Benjamin Schlichtmann, Dongsuk Kim, Vellareddy Anantharam, Arthi Kanthasamy, Balaji Narasimhan, Balaraman Kalyanaraman, Anumantha G. Kanthasamy

Physics Faculty Research and Publications

Aims: Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive motor deficits and degeneration of dopaminergic neurons. Caused by a number of genetic and environmental factors, mitochondrial dysfunction and oxidative stress play a role in neurodegeneration in PD. By selectively knocking out mitochondrial transcription factor A (TFAM) in dopaminergic neurons, the transgenic MitoPark mice recapitulate many signature features of the disease, including progressive motor deficits, neuronal loss, and protein inclusions. In the present study, we evaluated the neuroprotective efficacy of a novel mitochondrially targeted antioxidant, Mito-apocynin, in MitoPark mice and cell culture models of neuroinflammation and mitochondrial dysfunction.

Results: …

Multiwavelength Follow-Up Of A Rare Icecube Neutrino Multiplet, Karen Andeen

Physics Faculty Research and Publications

On February 17, 2016, the IceCube real-time neutrino search identified, for the first time, three muon neutrino candidates arriving within 100 s of one another, consistent with coming from the same point in the sky. Such a triplet is expected once every 13.7 years as a random coincidence of background events. However, considering the lifetime of the follow-up program the probability of detecting at least one triplet from atmospheric background is 32%. Follow-up observatories were notified in order to search for an electromagnetic counterpart. Observations were obtained by Swift’s X-ray telescope, by ASAS-SN, LCO and MASTER at optical wavelengths, …

Constraints On Galactic Neutrino Emission With Seven Years Of Icecube Data, Karen Andeen

Physics Faculty Research and Publications

The origins of high-energy astrophysical neutrinos remain a mystery despite extensive searches for their sources. We present constraints from seven years of IceCube Neutrino Observatory muon data on the neutrino flux coming from the Galactic plane. This flux is expected from cosmic-ray interactions with the interstellar medium or near localized sources. Two methods were developed to test for a spatially extended flux from the entire plane, both of which are maximum likelihood fits but with different signal and background modeling techniques. We consider three templates for Galactic neutrino emission based primarily on gamma-ray observations and models that cover a wide …

Interproximal Distance Analysis Of Stereolithographic Casts Made By Cad-Cam Technology: An In Vitro Study, Melanie Hoffman, Seok-Hwan Cho, Naveen K. Bansal

Mathematics, Statistics and Computer Science Faculty Research and Publications

Statement of problem

The accuracy of interproximal distances of the definitive casts made by computer-aided design and computer-aided manufacturing (CAD-CAM) technology is not yet known.

Purpose

The purpose of this in vitro study was to compare the interproximal distances of stereolithographic casts made by CAD-CAM technology with those of stone casts made by the conventional method.

Material and methods

Dentoform teeth were prepared for a single ceramic crown on the maxillary left central incisor, a 3-unit fixed dental prosthesis (FDP) on the second premolar for a metal-ceramic crown, and a maxillary right first molar for a metal crown. Twenty digital …

Catalytic Reduction Of Bisulfite By Myoglobin/Surfactant Films, Radalla Abdellatty, Md. Hafizur Rahman, Michael D. Ryan

Chemistry Faculty Research and Publications

The voltammetry of bisulfite at a film formed with myoglobin was studied in aqueous solutions. A broad wave was observed for the reduction of bisulfite. Using controlled potential electrolysis, the reduction at potentials positive of the Fe^II/Fe^Iwave formed dithionite exclusively. As the potential approached the region for the Fe^II/Fe^I reduction, bisulfite was reduced primarily to HS⁻. Even at the negative potentials, some dithionite was still formed, which could then be electrochemically reduced to thiosulfate. Analysis of the formation of HS⁻, dithionite and thiosulfate during the electrolysis was consistent with …

Spectroscopic And Computational Studies Of Reversible O2 Binding By A Cobalt Complex Of Relevance To Cysteine Dioxygenase, Anne A. Fischer, Sergey V. Lindeman, Adam T. Fiedler

Chemistry Faculty Research and Publications

The substitution of non-native metal ions into metalloenzyme active sites is a common strategy for gaining insights into enzymatic structure and function. For some nonheme iron dioxygenases, replacement of the Fe(II) center with a redox-active, divalent transition metal (e.g., Mn, Co, Ni, Cu) gives rise to an enzyme with equal or greater activity than the wild-type enzyme. In this manuscript, we apply this metal-substitution approach to synthetic models of the enzyme cysteine dioxygenase (CDO). CDO is a nonheme iron dioxygenase that initiates the catabolism of L-cysteine by converting this amino acid to the corresponding sulfinic acid. Two mononuclear …

Multi-Messenger Observations Of A Binary Neutron Star Merger, Karen Andeen

Physics Faculty Research and Publications

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg² at a luminosity distance of Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to …

Dodrant-Homomorphic Encryption For Cloud Databases Using Table Lookup, Thomas Schwarz

Mathematics, Statistics and Computer Science Faculty Research and Publications

Users of large commercial databases increasingly want to outsource their database operations to a cloud service providers, but guaranteeing the privacy of data in an outsourced database has become the major obstacle to this move. Encrypting all data solves the privacy issue, but makes many operations on the data impossible in the cloud, unless the service provider has the capacity to decrypt data temporarily. Homomorphic encryption would solve this issue, but despite great and on-going progress, it is still far from being operationally feasible. In 2015, we presented what we now call dodrant-homomorphic encryption, a method that encrypts numeric values …

Spin Crossover Behavior Of N-Confused C-Scorpionate Complexes Of Iron(Ii) Trifluoromethanesulfonate, Kristin Joy Meise

Master's Theses (2009 -)

An understanding of the molecular properties that influence highly-cooperative SCO behavior is critical in the development of new electronic materials. The purpose of this thesis work is to more fully examine whether hydrogen bonding interactions can be used to assemble iron(II) scorpionate complexes and whether this leads to abruptness in the SCO behavior. In this contribution, new N-confused C-scorpionate ligands are prepared with two ‘normal’ pz* groups ( = 3,5-dimethylpyrazol-1yl) and a ‘confused’ pyrazolyl with either an N-H, HL*, or an N-Tosyl (Tosyl = p-toluenesulfonyl), TsL*, bound to a central methine. These bulky ligands complement those previously described, HL and …

Ruthenium Catalyzed Deaminative Coupling Reaction Of Amines Via C-N Bond Activation, Pandula T. Kirinde Arachchige

Master's Theses (2009 -)

C–N bond activation via transition-metal catalyst has attracted much attention during the past two decades. This strategy has become one of the most promising way to generate secondary amines, which are very important in a broad spectrum of applications in pharmaceutical industry, synthetic organic chemistry and material science. The secondary amines can be utilized as an important synthetic intermediate for further manipulations. The in-situ formed catalytic system generated from the tetranuclear Ru–H complex with 4-(1,1-dimethylethyl)-1,2-benzenediol ligand was found to be effective for the synthesis of secondary amines from the direct deaminative coupling of amines. The ruthenium catalyst was highly effective …

Racemic And Enantiopure Forms Of 3‐Ethyl‐3‐Phenylpyrrolidin‐2‐One Adopt Very Different Crystal Structures, Arcadius V. Krivoshein, Sergey V. Lindeman, Tatiana V. Timofeeva, Victor N. Khrustalev

Chemistry Faculty Research and Publications

3‐Ethyl‐3‐phenylpyrrolidin‐2‐one (EPP) is an experimental anticonvulsant based on the newly proposed α‐substituted amide group pharmacophore. These compounds show robust activity in animal models of drug‐resistant epilepsy and are thus promising for clinical development. In order to understand pharmaceutically relevant properties of such compounds, we are conducting an extensive investigation of their structures in the solid state. In this article, we report chiral high‐performance liquid chromatography (HPLC) separation, determination of absolute configuration of enantiomers, and crystal structures of EPP. Preparative resolution of EPP enantiomers by chiral HPLC was accomplished on the Chiralcel OJ stationary phase in the polar‐organic mode. Using …

The Double-Edged Sword: A Mixed Methods Study Of The Interplay Between Bipolar Disorder And Technology Use, Mark Matthews, Elizabeth Murnane, Jaime Snyder, Shion Guha, Pamara Chang, Gavin Doherty, Geri K. Gay

Mathematics, Statistics and Computer Science Faculty Research and Publications

Human behavior is increasingly reflected or acted out through technology. This is of particular salience when it comes to changes in behavior associated with serious mental illnesses including schizophrenia and bipolar disorder. Early detection is crucial for these conditions but presently very challenging to achieve. Potentially, characteristics of these conditions' traits and symptoms, at both idiosyncratic and collective levels, may be detectable through technology use patterns. In bipolar disorder specifically, initial evidence associates changes in mood with changes in technology-mediated communication patterns. However much less is known about how people with bipolar disorder use technology more generally in their lives, …

Spectral Characterization Of Cytochromes P450 Active Sites Using Nmr And Resonance Raman Spectroscopy, Remigio Usai

Dissertations (1934 -)

The Cytochrome P450 (P450s) has been the subject of intense research for over six decades. An efficient approach for isotopic labeling of the prosthetic group in heme proteins was exploited to produce an analogue of the soluble bacterial cytochrome P450cam (P450cam) that contains a 13C labeled-protoheme prosthetic group. HU227 strain of E. coli, which lacks the δ-aminolevulinic acid (δ-ALA) synthase gene, was employed in the heterologous expression of P450cam harboring a prosthetic group labeled with 13C at the Cm and Cα positions by growing cells in the presence of [5-13C] δ-ALA, which was synthesized in four steps from [2-13C] glycine. …

Nucleotide-Dependent Preferential Localization Of Ras In Model Membranes With Lipid Raft Nanodomains, Anna Shishina

Dissertations (1934 -)

Membrane proteins constitute a third of all proteins in the cell and more than 50% of drug targets. However, the analysis of membrane proteins has many challenges owing to their partially hydrophobic surfaces, flexibility and lack of stability. One example of an essential membrane protein is Ras superfamily. Ras is a small monomeric GTPase involved in regulation of cell growth, proliferation and differentiation. Therefore, Ras and its effectors are among the most important targets for cancer therapy. A detailed knowledge of the processes occurring during signal propagation via Ras might help to elucidate the mechanisms of the involved signal cascades. …

Measurement Of The Νμ Energy Spectrum With Icecube-79, Karen Andeen

Physics Faculty Research and Publications

IceCube is a neutrino observatory deployed in the glacial ice at the geographic South Pole. The νμ energy unfolding described in this paper is based on data taken with IceCube in its 79-string configuration. A sample of muon neutrino charged-current interactions with a purity of 99.5% was selected by means of amultivariate classification process based on machine learning. The subsequent unfolding was performed using the software TRUEE. The resulting spectrum covers an E_ν-range of more than four orders of magnitude from 125 GeV to 3.2 PeV. Compared to the Honda atmospheric neutrino flux model, the energy spectrum shows …

Computational Strategies In Uncertainty Quantification For Hazard Mapping, Regis Rutarindwa

Dissertations (1934 -)

There are many hazards associated with volcanic activities. Amongst them are Pyroclastic flows; a mixture of rock fragments, debris and hot gases that flow down the slope of actives volcanoes at high velocities. These flows have proven to be devastating, and at the same time more than 500 millions people in the world live within potential exposure to such a hazard. A few approaches have been used to try to mitigate the impact of volcanic hazard in general. These include remote sensing technology and developing hazard maps – a graphic representation of safe and risky zones for a given volcanic …

Feature Space Augmentation: Improving Prediction Accuracy Of Classical Problems In Cognitive Science And Computer Vison, Piyush Saxena

Dissertations (1934 -)

The prediction accuracy in many classical problems across multiple domains has seen a rise since computational tools such as multi-layer neural nets and complex machine learning algorithms have become widely accessible to the research community. In this research, we take a step back and examine the feature space in two problems from very different domains. We show that novel augmentation to the feature space yields higher performance. Emotion Recognition in Adults from a Control Group: The objective is to quantify the emotional state of an individual at any time using data collected by wearable sensors. We define emotional state as …

On Congruence Lattices Of Nilsemigroups, Alexander L. Popovich, Peter Jones

Mathematics, Statistics and Computer Science Faculty Research and Publications

We prove that the congruence lattice of a nilsemigroup is modular if and only if the width of the semigroup, as a poset, is at most two, and distributive if and only if its width is one. In the latter case, such semigroups therefore coincide with the nil Δ">Δ Δ -semigroups. It is further shown that if a finitely generated nilsemigroup has modular congruence lattice, then the semigroup is finite.

Antihydrogen Accumulation For Fundamental Symmetry Tests, Timothy Tharp, M. Ahmadi, P. Nolan, P. Pusa, B. X. R. Alves, T. Friesen, C. O. Rasmussen, G. Stutter, C. J. Baker, M. Charlton, S. Eriksson, C. A. Isaac, S. A. Jones, N. Madsen, D. Maxwell, M. Sameed, D. P. Van Der Werf, W. Bertsche, M. A. Johnson, E. Butler, A. Capra, R. Collister, M. C. Fujiwara, L. Kurchaninov, J. T. K. Mckenna, J. M. Michan, K. Olchanski, A. Olin, C. Carruth, J. Fajans, J. S. Wurtele, C. L. Cesar, R. L. Sacramento, D. M. Silveira, S. Cohen, A. Evans, C. So, R. I. Thompson, N. Evetts, W. N. Hardy, T. Momose, A. Gutierrez, M. E. Hayden, J. J. Munich, A. Ishida, S. Jonsell, M. Mathers, S. Menary, J. E. Thompson, J.M. Michan, F. Robicheaux, E. Sarid, S. Stracha

Physics Faculty Research and Publications

Antihydrogen, a positron bound to an antiproton, is the simplest anti-atom. Its structure and properties are expected to mirror those of the hydrogen atom. Prospects for precision comparisons of the two, as tests of fundamental symmetries, are driving a vibrant programme of research. In this regard, a limiting factor in most experiments is the availability of large numbers of cold ground state antihydrogen atoms. Here, we describe how an improved synthesis process results in a maximum rate of 10.5 ± 0.6 atoms trapped and detected per cycle, corresponding to more than an order of magnitude improvement over previous work. Additionally, …

Altering The Coordination Of Iron Porphyrins By Ionic Liquid Nanodomains In Mixed Solvent Systems, Abderrahman Atifi, Michael D. Ryan

Chemistry Faculty Research and Publications

The solvent environment around iron porphyrin complexes was examined using mixed molecular/RTIL (room temperature ionic liquid) solutions. The formation of nanodomains in these solutions provides different solvation environments for substrates that could have significant impact on their chemical reactivity. Iron porphyrins (Fe(P)), whose properties are sensitive to solvent and ligation changes, were used to probe the molecular/RTIL environment. The addition of RTILs to molecular solvents shifted the redox potentials to more positive values. When there was no ligation change upon reduction, the shift in the E° values were correlated to the Gutmann acceptor number, as was observed for other …

Search For Astrophysical Sources Of Neutrinos Using Cascade Events In Icecube, Karen Andeen

Physics Faculty Research and Publications

The IceCube neutrino observatory has established the existence of a flux of high-energy astrophysical neutrinos, which is inconsistent with the expectation from atmospheric backgrounds at a significance greater than 5σ. This flux has been observed in analyses of both track events from muon neutrino interactions and cascade events from interactions of all neutrino flavors. Searches for astrophysical neutrino sources have focused on track events due to the significantly better angular resolution of track reconstructions. To date, no such sources have been confirmed. Here we present the first search for astrophysical neutrino sources using cascades interacting in IceCube with …

When Substituents Do Not Matter: Frontier Orbitals Explain The Unusually High And Invariant Oxidation Potential In Alkoxy-, Alkyl-, And H-Substituted Iptycenes, Maxim V. Ivanov, Denan Wang, Shriya Wadumethrige, Rajendra Rathore

Chemistry Faculty Research and Publications

Frontier molecular orbitals (FMOs) have played a critical role in predicting reactivity/selectivity of pericyclic reactions. Here we show that the structurally similar iptycene-based hydroquinone ether (HE), that is, ^MeOIpt and ^BOHE/^BHHE, molecules have drastically different ordering of bisallylic and quinoidal FMOs. They are almost degenerate in ^BOHE/^BHHE, while in ^MeOIpt, the bisallylic orbital lies far below the quinoidal HOMO. Oxidation of ^BOHE/^BHHE induces coplanarization of the methoxy group and destabilizes the bisallylic HOMO, leading to a relatively low oxidation potential. In ^MeOIpt, considerable energy …

Search For Neutrinos From Dark Matter Self-Annihilations In The Center Of The Milky Way With 3 Years Of Icecube/Deepcore, Karen Andeen, Icecube Collaboration

Physics Faculty Research and Publications

We present a search for a neutrino signal from dark matter self-annihilations in the Milky Way using the IceCube Neutrino Observatory (IceCube). In 1005 days of data we found no significant excess of neutrinos over the background of neutrinos produced in atmospheric air showers from cosmic ray interactions. We derive upper limits on the velocity averaged product of the dark matter self-annihilation cross section and the relative velocity of the dark matter particles ⟨ σ A v ⟩

. Upper limits are set for dark matter particle candidate masses ranging from 10 GeV up to 1 TeV while considering annihilation …

Observation Of The Hyperfine Spectrum Of Antihydrogen, M. Ahmadi, B. X. R. Alves, C. J. Baker, W. Bertsche, E. Butler, A. Capra, C. Carruth, C. L. Cesar, M. Charlton, S. Cohen, R. Collister, S. Eriksson, A. Evans, N. Evetts, J. Fajans, T. Friesen, M. C. Fujiwara, D. R. Gill, A. Gutierrez, J. S. Hangst, W. N. Hardy, M. E. Hayden, C. A. Isaac, A. Ishida, M. A. Johnson, S. A. Jones, S. Jonsell, L. Kurchaninov, N. Madsen, M. Mathers, D. Maxwell, J. T. K. Mckenna, S. Menary, J. M. Michan, T. Momose, J. J. Munich, P. Nolan, K. Olchanski, A. Olin, P. Pusa, C. O. Rasmussen, F. Robicheaux, R. L. Sacramento, M. Sameed, E. Sarid, D. M. Silveira, S. Stracka, G. Stutter, C. So, Timothy Tharp, J. E. Thompson, R. I. Thompson, D. P. Van Der Werf, J. S. Wurtele

Physics Faculty Research and Publications

The observation of hyperfine structure in atomic hydrogen by Rabi and co-workers^1,2,3 and the measurement⁴ of the zero-field ground-state splitting at the level of seven parts in 10¹³ are important achievements of mid-twentieth-century physics. The work that led to these achievements also provided the first evidence for the anomalous magnetic moment of the electron^5,6,7,8, inspired Schwinger’s relativistic theory of quantum electrodynamics^9,10 and gave rise to the hydrogen maser¹¹, which is a critical component of modern navigation, geo-positioning and very-long-baseline interferometry …

Implant Treatment In The Predoctoral Clinic: A Retrospective Database Study Of 1091 Patients, Soni Prasad, Christopher Hambrook, Eric Reigle, Katherine Sherman, Naveen K. Bansal, Arthur F. Hefti

Mathematics, Statistics and Computer Science Faculty Research and Publications

Purpose: This retrospective study was conducted at the Marquette University School of Dentistry to (1) characterize the implant patient population in a predoctoral clinic, (2) describe the implants inserted, and (3) provide information on implant failures.

Materials and Methods: The study cohort included 1091 patients who received 1918 dental implants between 2004 and 2012, and had their implants restored by a crown or a fixed dental prosthesis. Data were collected from patient records, entered in a database, and summarized in tables and figures. Contingency tables were prepared and analyzed by a chi-squared test. The cumulative survival probability of implants was …