scholarly journals Digital Design of a Universal Rat Intraoral Device for Therapeutic Evaluation of a Topical Formulation against Candida-Associated Denture Stomatitis

2019 ◽  
Vol 87 (12) ◽  
Author(s):  
Ahmed S. Sultan ◽  
Alexandra M. Rizk ◽  
Taissa Vila ◽  
Yadong Ji ◽  
Radi Masri ◽  
...  
Keyword(s):  
Oral Candidiasis ◽  
Three Dimensional ◽  
Opportunistic Pathogen ◽  
Digital Design ◽  
The Novel ◽  
Topical Formulation ◽  
Content Type ◽  
Denture Stomatitis ◽  
Intraoral Device ◽  
Technological Advances

ABSTRACT Candida-associated denture stomatitis (DS) is a persistent and chronic oral infection of the denture-bearing palatal mucosa. DS stems from the ability of the fungal opportunistic pathogen Candida albicans to adhere to denture material and invade palatal tissue. Although DS is the most prevalent form of oral candidiasis, there are currently no feasible therapeutic strategies for the prevention of this recurrent condition. We developed a peptide-based antimicrobial bioadhesive formulation specifically designed for oral topical formulation. In this study, we aimed to evaluate the applicability of the novel formulation for the prevention of C. albicans colonization on denture material and development of clinical disease. To that end, using the latest technological advances in dental digital design and three-dimensional (3D) printing, we fabricated an intraoral device for rats with universal fit. The device was successfully installed and used to develop clinical DS. Importantly, by taking a preventative therapeutic approach, we demonstrated the potential clinical utility of the novel formulation as a safe and feasible prophylactic agent against DS.

scholarly journals Iron Restriction to Clinical Isolates ofCandida albicansby the Novel Chelator DIBI Inhibits Growth and Increases Sensitivity to AzolesIn VitroandIn Vivoin a Murine Model of Experimental Vaginitis

2018 ◽  
Vol 62 (8) ◽  
Author(s):  
Kimberley A. Savage ◽  
Maria del Carmen Parquet ◽  
David S. Allan ◽  
Ross J. Davidson ◽  
Bruce E. Holbein ◽  
...  
Keyword(s):  
Iron Homeostasis ◽  
Iron Chelation ◽  
Opportunistic Pathogen ◽  
Clinical Isolates ◽  
Cell Multiplication ◽  
The Novel ◽  
Content Type ◽  
Sensitive Isolate ◽  
Human Infections

ABSTRACTCandida albicansis an important opportunistic pathogen causing various human infections that are often treated with azole antifungals. The U.S. CDC now regards developing candidal antifungal resistance as a threat, creating a need for new and more effective antifungal treatments. Iron is an essential nutrient for all living cells, and there is growing evidence that interference with iron homeostasis ofC. albicanscan improve its response to antifungals. This study was aimed at establishing whether withholding iron by currently used medical iron chelators and the novel chelator DIBI could restrict growth and also enhance the activity of azoles against clinical isolates ofC. albicans. DIBI, but not deferoxamine or deferiprone, inhibited the growth ofC. albicansat relatively low concentrationsin vitro, and this inhibition was reversed by iron addition. DIBI in combination with various azoles demonstrated stronger growth inhibition than the azoles alone and greatly prolonged the inhibition of cell multiplication. In addition, the administration of DIBI along with fluconazole (FLC) to mice inoculated with an FLC-sensitive isolate in a model of experimentalC. albicansvaginitis showed a markedly improved clearance of infection. These results suggest that iron chelation by DIBI has the potential to enhance azole efficacy for the treatment of candidiasis.

Effects of plasma nitriding interlayer on adhesion and tribological behaviors of AlTiSiN coating

2021 ◽  
Vol 73 (6) ◽  
pp. 945-953
Author(s):  
Mengjuan Yin ◽  
Wenping Liang ◽  
Qiang Miao ◽  
Shiwei Zuo ◽  
Haiyang Yu ◽  
...  
Keyword(s):  
Plasma Nitriding ◽  
Three Dimensional ◽  
Wear Property ◽  
The Novel ◽  
Content Type ◽  
The Matrix ◽  
Narrow Width ◽  
Glow Plasma ◽  
Excellent Adhesion ◽  
Ta15 Alloy

Purpose This study aims to the service life of TA15 alloy by solving the problem of the binding force between the matrix and AlTiSiN coating. The effect of a plasma nitriding (PN) interlayer on the magnetron-sputtered AlTiSiN coating was also investigated in detail. Design/methodology/approach The double-glow plasma alloying (DGPA) and magnetron sputtering (MS) techniques were combined as a new approach to realize a bilayer on TA15 consisting of an AlTiSiN layer with a PN interlayer. A TiN interlayer was formed via co-diffusion during the PN conducted at 1050°C for 3 h. Findings The PN interlayer can effectively improve the adhesion between coating and matrix; the PN/AlTiSiN coating presented excellent adhesion (80.1 N) and anti-wear property with a nano-hardness of 18.62 GPa. The resulting three-dimensional wear-track morphology exhibited a shallow depth and a narrow width. Originality/value The novel combination of the DGPA and MS technologies, using an infiltration layer rather than a coating one as the intermediate layer, can effectively enhance the adhesion between AlTiSiN coating and TA15 matrix. Meanwhile, the gradient layer can effectively improve both surface bearing and wear resistance.

From consumer to prosumer: a supply chain revolution in 3D printing

2019 ◽  
Vol 49 (2) ◽  
pp. 200-216 ◽  
Author(s):  
Sam Halassi ◽  
Janjaap Semeijn ◽  
Nadine Kiratli
Keyword(s):  
Supply Chains ◽  
Operations Management ◽  
Online Survey ◽  
Business Models ◽  
Three Dimensional ◽  
Point Of View ◽  
Consumer Acceptance ◽  
Content Type ◽  
Technological Advances ◽  
Do It Yourself

Purpose Recent technological advances in three-dimensional printing (3DP) may disrupt traditional manufacturing and logistics processes. Because the increasing availability of 3DP service centers, affordable 3D printers, and online platforms empower consumers to design and print objects at home, companies must determine the motives that lead consumers to become prosumers so that they can establish appropriate business models and supply chains. Accordingly, the purpose of this paper is to identify factors that drive consumer acceptance and use of 3DP technologies. Design/methodology/approach The explanatory conceptual framework, based on the extended unified theory of acceptance and use of technology, undergoes empirical testing with a sample of 196 3DP consumers who participated in an online survey. Findings Facilitating conditions, hedonic motivation and a do-it-yourself mentality are key determinants of consumer acceptance and use intention of 3DP technology. Practical implications Companies can use these insights about consumers’ motivation to determine whether their use of 3DP technology threatens current business models or supply chains. In turn, they can develop new ideas about how to adapt these features, as well as identify opportunities for new revenue streams. Originality/value Unlike most extant literature on 3DP in manufacturing and logistics domains, this study takes consumers’ point of view to shed light on an issue typically investigated from an operations management perspective.

Stabilization and circuit implementation of a novel chemical oscillating chaotic system

Circuit World ◽  
2019 ◽  
Vol 45 (2) ◽  
pp. 93-106
Author(s):  
Li Xiong ◽  
Wanjun Yin ◽  
Xinguo Zhang
Keyword(s):  
Chaotic System ◽  
Control Method ◽  
Three Dimensional ◽  
Chaotic Attractors ◽  
The Novel ◽  
Content Type ◽  
Initial Values ◽  
Parameters Selection ◽  
Chaotic Circuits ◽  
Simulation Results

Purpose This paper is aimed at investigating a novel chemical oscillating chaotic system with different attractors at fixed parameters. The typical dynamical behavior of the new chemical oscillating system is discussed, and it is found that the state selection is dependent on initial values. Then, the stabilization problem of the chemical oscillating attractors is investigated analytically and numerically. Subsequently, the novel electronic circuit of the proposed chemical oscillating chaotic system are constructed, and the influences of the changes of circuit parameters on chemical oscillating chaotic attractors are investigated. Design/methodology/approach The different attractors of the novel chemical oscillating chaotic system are investigated by changing the initial values under fixed parameters. Moreover, the active control and adaptive control methods are presented to make the chemical oscillating chaotic systems asymptotically stable at the origin based on the Lyapunov stability theory. The influences on chemical oscillating chaotic attractors are also verified by changing the circuit parameters. Findings It is found that the active control method is easier to be realized by using physical components because of its less control signal and lower cost. It is also confirmed that the adaptive control method enjoys strong anti-interference ability because of its large number of selected controllers. What can be seen from the simulation results is that the chaotic circuits are extremely dependent on circuit parameters selection. Comparisons between MATLAB simulations and Multisim simulation results show that they are consistent with each other and demonstrate that changing attractors of the chemical oscillating chaotic system exist. It is conformed that circuit parameters selection can be effective to control and realize chaotic circuits. Originality/value The different attractors of the novel chemical oscillating chaotic system are investigated by changing the initial values under fixed parameters. The characteristic of the chemical oscillating attractor is that the basin of attraction of the three-dimensional attractor is located in the first quadrant of the eight quadrants of the three-dimensional space, and the ranges of the three variables are positive. This is because the concentrations of the three chemical substances are all positive.

scholarly journals The Candida albicans ESCRT Pathway Makes Rim101-Dependent and -Independent Contributions to Pathogenesis

2010 ◽  
Vol 9 (8) ◽  
pp. 1203-1215 ◽  
Author(s):  
Julie M. Wolf ◽  
Diedre J. Johnson ◽  
David Chmielewski ◽  
Dana A. Davis
Keyword(s):  
Candida Albicans ◽  
Cell Damage ◽  
Oral Candidiasis ◽  
Opportunistic Pathogen ◽  
High Dose ◽  
Wild Type ◽  
Content Type ◽  
Fungal Burden ◽  
Endosomal Membrane ◽  
Independent Functions

ABSTRACT Candida albicans is an opportunistic pathogen that colonizes diverse mucosal niches with distinct environmental characteristics. To adapt to these different sites, C. albicans must activate and attenuate a variety of signal transduction pathways. A mechanism of signal attenuation is through receptor endocytosis and subsequent vacuolar degradation, which requires the endosomal sorting complex required for transport (ESCRT) pathway. This pathway comprises several polyprotein complexes (ESCRT-0, -I, -II, -III, and -DS) that are sequentially recruited to the endosomal membrane. The ESCRT pathway also activates the Rim101 transcription factor, which governs expression of genes required for virulence. Here, we tested the hypothesis that the ESCRT pathway plays a Rim101-independent role(s) in pathogenesis. We generated deletion mutants in each ESCRT complex and determined that ESCRT-I, -II, and -III are required for Rim101 activation but that ESCRT-0 and ESCRT-DS are not. We found that the ESCRT-0 member Vps27 and ESCRT-DS components are required to promote epithelial cell damage and, using a murine model of oral candidiasis, found that the vps27Δ/Δ mutant had a decreased fungal burden compared to that of the wild type. We found that a high-dose inoculum can compensate for fungal burden defects but that mice colonized with the vps27Δ/Δ strain exhibit less morbidity than do mice infected with the wild-type strain. These results demonstrate that the ESCRT pathway has Rim101-independent functions for C. albicans virulence.

High accuracy disturbance observer-based agile attitude stabilization with three-dimensional MSW

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Javad Tayebi ◽  
Chao Han ◽  
Yuanjin Yu
Keyword(s):  
Attitude Control ◽  
High Frequency ◽  
Disturbance Observer ◽  
Three Dimensional ◽  
High Accuracy ◽  
The Novel ◽  
Content Type ◽  
Attitude Stabilization ◽  
Steering Law ◽  
Long Lifetime

Purpose The purpose of this paper is agile attitude control design with the novel three-dimensional (3D) magnetically suspended wheel (MSW) that is the preferred type for agile maneuvering compared to conventional control moment gyro due to frictionless, low vibration and long lifetime. This system does not require a separate steering law for pyramid arrangement to derive tilt angles. It is also conducting an agile maneuver with high accuracy despite the high-frequency disturbances. Design/methodology/approach In this paper, a disturbance observer-based attitude stabilization method is proposed for an agile satellite with a pyramid cluster of the novel 3D magnetically suspended wheel actuator. This strategy includes a disturbance observer and a linear quadratic regulator controller. The rotor shaft deflection of MSW is actively controlled to reduce vibration and producing gyro torque. The deflection angle of the pyramid cluster MSWs considered as control parameters. The closed-loop stability is proved by using the Lyapunov strategy. The efficiency and performance of the offered method verified by numerical simulation via MATLAB/SIMULINK software. Findings According to simulation results, the disturbance observer-based control controller stabilized the system with high accuracy and optimal tilt angles without any extra steering law equation. Hence, the system speed is increased, and the system error is minimized without separate steering law. Practical implications The magnetically suspended wheel is a new kind of inertia actuator for attitude control that has several benefits such as frictionless, high-speed rotor, clean environment and low vibration compared to the traditional wheel. It has complex nonlinear dynamics that cause have complicated controller design. The proposed strategy stabilizes the system and conducting an agile maneuver with high precision despite the high-frequency disturbances. It is applicable for some missions requiring high accuracies, like Earth observation and the solar observation mission that require a very accurate pointing control and a long lifetime. Originality/value This paper is the initial paper to design a pyramid array for magnetically suspended wheels. Compared to other research, this method doesn’t need a separate steering law of the MSWs cluster and presented optimal tilt angles with less computational. Also, it designs a disturbance observer-based controller for this system that proposed high accuracy and agile stabilization.

scholarly journals Non-invasive implementation of nonlinear isogeometric analysis in an industrial FE software

2019 ◽  
Vol 37 (1) ◽  
pp. 237-261 ◽  
Author(s):  
Marie Tirvaudey ◽  
Robin Bouclier ◽  
Jean-Charles Passieux ◽  
Ludovic Chamoin
Keyword(s):  
Finite Element ◽  
Isogeometric Analysis ◽  
Three Dimensional ◽  
Nonlinear Problems ◽  
The Novel ◽  
Input Output ◽  
Element Analysis ◽  
Content Type ◽  
Lagrange Polynomials ◽  
Non Invasive

Purpose The purpose of this paper is to further simplify the use of NURBS in industrial environnements. Although isogeometric analysis (IGA) has been the object of intensive studies over the past decade, its massive deployment in industrial analysis still appears quite marginal. This is partly due to its implementation, which is not straightforward with respect to the elementary structure of finite element (FE) codes. This often discourages industrial engineers from adopting isogeometric capabilities in their well-established simulation environment. Design/methodology/approach Based on the concept of Bézier and Lagrange extractions, a novel method is proposed to implement IGA from an existing industrial FE code with the aim of bringing human implementation effort to the minimal possible level (only using standard input-output of finite element analysis (FEA) codes, avoid code-dependent subroutines implementation). An approximate global link to go from Lagrange polynomials to non-uniform-rational-B-splines functions is formulated, which enables the whole FE routines to be untouched during the implementation. Findings As a result, only the linear system resolution step is bypassed: the resolution is performed in an external script after projecting the FE system onto the reduced, more regular and isogeometric basis. The novel procedure is successfully validated through different numerical experiments involving linear and nonlinear isogeometric analyses using the standard input/output of the industrial FE software Code_Aster. Originality/value A non-invasive implementation of IGA into FEA software is proposed. The whole FE routines are untouched during the novel implementation procedure; a focus is made on the IGA solution of nonlinear problems from existing FEA software; technical details on the approach are provided by means of illustrative examples and step-by-step implementation; the methodology is evaluated on a range of two- and three-dimensional elasticity and elastoplasticity benchmarks solved using the commercial software Code_Aster.

Stereotactic radiosurgery versus stereotactic radiotherapy for patients with vestibular schwannoma: a Leksell Gamma Knife Society 2000 debate

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 90-92 ◽  
Author(s):  
Mark E. Linskey
Keyword(s):  
Gamma Knife ◽  
Stereotactic Radiotherapy ◽  
Three Dimensional ◽  
Late Recurrence ◽  
Vestibular Schwannomas ◽  
Tumor Control ◽  
Complication Rates ◽  
Content Type ◽  
Single Fraction ◽  
Fine Print

✓ By definition, the term “radiosurgery” refers to the delivery of a therapeutic radiation dose in a single fraction, not simply the use of stereotaxy. Multiple-fraction delivery is better termed “stereotactic radiotherapy.” There are compelling radiobiological principles supporting the biological superiority of single-fraction radiation for achieving an optimal therapeutic response for the slowly proliferating, late-responding, tissue of a schwannoma. It is axiomatic that complication avoidance requires precise three-dimensional conformality between treatment and tumor volumes. This degree of conformality can only be achieved through complex multiisocenter planning. Alternative radiosurgery devices are generally limited to delivering one to four isocenters in a single treatment session. Although they can reproduce dose plans similar in conformality to early gamma knife dose plans by using a similar number of isocenters, they cannot reproduce the conformality of modern gamma knife plans based on magnetic resonance image—targeted localization and five to 30 isocenters. A disturbing trend is developing in which institutions without nongamma knife radiosurgery (GKS) centers are championing and/or shifting to hypofractionated stereotactic radiotherapy for vestibular schwannomas. This trend appears to be driven by a desire to reduce complication rates to compete with modern GKS results by using complex multiisocenter planning. Aggressive advertising and marketing from some of these centers even paradoxically suggests biological superiority of hypofractionation approaches over single-dose radiosurgery for vestibular schwannomas. At the same time these centers continue to use the term radiosurgery to describe their hypofractionated radiotherapy approach in an apparent effort to benefit from a GKS “halo effect.” It must be reemphasized that as neurosurgeons our primary duty is to achieve permanent tumor control for our patients and not to eliminate complications at the expense of potential late recurrence. The answer to minimizing complications while maintaining maximum tumor control is improved conformality of radiosurgery dose planning and not resorting to homeopathic radiosurgery doses or hypofractionation radiotherapy schemes.

scholarly journals Novel Aggregation Properties of Candida albicans Secreted Aspartyl Proteinase Sap6 Mediate Virulence in Oral Candidiasis

2015 ◽  
Vol 83 (7) ◽  
pp. 2614-2626 ◽  
Author(s):  
Rohitashw Kumar ◽  
Darpan Saraswat ◽  
Swetha Tati ◽  
Mira Edgerton
Keyword(s):  
Candida Albicans ◽  
Epithelial Cells ◽  
Oral Candidiasis ◽  
Oral Microbiome ◽  
Proteinase Activity ◽  
Adhesion Properties ◽  
Content Type ◽  
Oral Epithelial Cells ◽  
Oral Epithelial ◽  
Cell Cell

Candida albicans, a commensal fungus of the oral microbiome, causes oral candidiasis in humans with localized or systemic immune deficiencies. Secreted aspartic proteinases (Saps) are a family of 10 related proteases and are virulence factors due to their proteolytic activity, as well as their roles in adherence and colonization of host tissues. We found that mice infected sublingually withC. albicanscells overexpressing Sap6 (SAP6OE and a Δsap8strain) had thicker fungal plaques and more severe oral infection, while infection with the Δsap6strain was attenuated. These hypervirulent strains had highly aggregative colony structurein vitroand higher secreted proteinase activity; however, the levels of proteinase activity ofC. albicansSaps did not uniformly match their abilities to damage cultured oral epithelial cells (SCC-15 cells). Hyphal induction in cells overexpressing Sap6 (SAP6OE and Δsap8cells) resulted in formation of large cell-cell aggregates. These aggregates could be produced in germinated wild-type cells by addition of native or heat-inactivated Sap6. Sap6 bound only to germinated cells and increasedC. albicansadhesion to oral epithelial cells. The adhesion properties of Sap6 were lost upon deletion of its integrin-binding motif (RGD) and could be inhibited by addition of RGD peptide or anti-integrin antibodies. Thus, Sap6 (but not Sap5) has an alternative novel function in cell-cell aggregation, independent of its proteinase activity, to promote infection and virulence in oral candidiasis.

scholarly journals Topological correlators and surface defects from equivariant cohomology

2020 ◽  
Vol 2020 (9) ◽  
Author(s):  
Rodolfo Panerai ◽  
Antonio Pittelli ◽  
Konstantina Polydorou
Keyword(s):  
Quantum Mechanics ◽  
Equivariant Cohomology ◽  
Surface Defects ◽  
Star Product ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Dimensional System ◽  
The Novel ◽  
One Dimensional ◽  
Dual Quantum

Abstract We find a one-dimensional protected subsector of $$ \mathcal{N} $$ N = 4 matter theories on a general class of three-dimensional manifolds. By means of equivariant localization we identify a dual quantum mechanics computing BPS correlators of the original model in three dimensions. Specifically, applying the Atiyah-Bott-Berline-Vergne formula to the original action demonstrates that this localizes on a one-dimensional action with support on the fixed-point submanifold of suitable isometries. We first show that our approach reproduces previous results obtained on S3. Then, we apply it to the novel case of S2× S1 and show that the theory localizes on two noninteracting quantum mechanics with disjoint support. We prove that the BPS operators of such models are naturally associated with a noncom- mutative star product, while their correlation functions are essentially topological. Finally, we couple the three-dimensional theory to general $$ \mathcal{N} $$ N = (2, 2) surface defects and extend the localization computation to capture the full partition function and BPS correlators of the mixed-dimensional system.

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