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Sparse-Grid Implementation of Fixed-Point Fast Sweeping WENO Schemes for Eikonal Equations

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Communications on Applied Mathematics and Computation 2024年第1期6卷 3-29页

作者： zachary M.Miksis Yong-Tao Zhang Department of Applied and Computational Mathematics and Statistics University of Notre DameNotre DameIN46556USA

Fixed-point fast sweeping methods are a class of explicit iterative methods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of fast sweeping schemes,fixed-point fast sweeping methods use the Gauss-Seidel iterations and alternating sweeping strategy to cover characteristics of hyperbolic PDEs in a certain direction simultaneously in each sweeping *** resulting iterative schemes have a fast convergence rate to steady-state ***,an advantage of fixed-point fast sweeping methods over other types of fast sweeping methods is that they are explicit and do not involve the inverse operation of any nonlinear local ***,they are robust and flexible,and have been combined with high-order accurate weighted essentially non-oscillatory(WENO)schemes to solve various hyperbolic PDEs in the *** multidimensional nonlinear problems,high-order fixed-point fast sweeping WENO methods still require quite a large amount of computational *** this technical note,we apply sparse-grid techniques,an effective approximation tool for multidimensional problems,to fixed-point fast sweeping WENO methods for reducing their computational ***,we focus on fixed-point fast sweeping WENO schemes with third-order accuracy(Zhang et al.2006[41]),for solving Eikonal equations,an important class of static Hamilton-jacobi(H-j)*** experiments on solving multidimensional Eikonal equations and a more general static H-j equation are performed to show that the sparse-grid computations of the fixed-point fast sweeping WENO schemes achieve large savings of CPU times on refined meshes,and at the same time maintain comparable accuracy and resolution with those on corresponding regular single grids.

关键词： Fixed-point fast sweeping methods Weighted essentially non-oscillatory(WENO)schemes Sparse grids Static Hamilton-jacobi(H-j)equations Eikonal equations

Anneal-free ultra-low loss silicon nitride integrated photonics

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Light(Science & Applications) 2024年第8期13卷 1565-1577页

作者： Debapam Bose Mark W.Harrington Andrei Isichenko Kaikai Liu jiawei Wang Nitesh Chauhan zachary L.Newman Daniel j.Blumenthal Department of Electrical and Computer Engineering University of California Santa BarbaraSanta BarbaraCA 93106USA Octave Photonics LouisvilleCO 80027USA

Heterogeneous and monolithic integration of the versatile low-loss silicon nitride platform with low-temperature materials such as silicon electronics and photonics,III–V compound semiconductors,lithium niobate,organics,and glasses has been inhibited by the need for high-temperature annealing as well as the need for different process flows for thin and thick *** techniques are needed to maintain the state-of-the-art losses,nonlinear properties,and CMOS-compatible processes while enabling this next generation of 3D silicon nitride *** report a significant advance in silicon nitride integrated photonics,demonstrating the lowest losses to date for an anneal-free process at a maximum temperature 250℃,with the same deuterated silane based fabrication flow,for nitride and oxide,for an order of magnitude range in nitride thickness without requiring stress mitigation or *** report record low anneal-free losses for both nitride core and oxide cladding,enabling 1.77 dBm-1 loss and 14.9 million Q for 80 nm nitride core waveguides,more than half an order magnitude lower loss than previously reported sub 300℃ *** 800 nm-thick nitride,we achieve as good as 8.66 dBm-1 loss and 4.03 million Q,the highest reported Q for a low temperature processed resonator with equivalent device area,with a median of loss and Q of 13.9 dBm-1 and 2.59 million each *** demonstrate laser stabilization with over 4 orders of magnitude frequency noise reduction using a thin nitride reference cavity,and using a thick nitride micro-resonator we demonstrate OPO,over two octave supercontinuum generation,and four-wave mixing and parametric gain with the lowest reported optical parametric oscillation threshold per unit resonator *** results represent a significant step towards a uniform ultra-low loss silicon nitride homogeneous and heterogeneous platform for both thin and thick waveguides capable of linear and nonlinear photonic circuits and integrat

关键词： resonator thick free

Utilization of RNA sequencing to investigate olfactory dysfunction in chronic rhinosinusitis without nasal polyps:A pilot study

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World journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 29-36页

作者： jorge A.Gutierrez III jeremy L.Barth Rodney j.Schlosser Thomas S.Edwards Timothy L.Smith zachary M.Soler Department of Otolaryngology-Head and Neck Surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Regenerative Medicine&Cell Biology Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery Oregon Health&Science UniversityPortlandOregonUSA

Objectives:Prior research on olfactory dysfunction in chronic rhinosinusitis(CRS)has focused on patients with polyps and suggests that direct inflammation of the olfactory cleft mucosa plays a contributory *** purpose of this study was to evaluate gene expression in superior turbinate mucosal specimens,comparing normosmic and dysosmic CRS patients without polyps(CRSsNP).Methods:Tissue samples were obtained from the superior turbinates of patients with CRSsNP at the time of endoscopic sinus *** subsequently underwent RNA sequencing and functional analysis to investigate biological pathways associated with differentially expressed genes between dysosmic(n=7)and normosmic(n=4)***:Differential gene expression analysis comparing dysosmic and normosmic CRSsNP patients showed upregulation of 563 genes and downregulation of 327 *** stringent criteria for multiple comparisons,one upregulated gene(Immediate Early Response 3[IER3])had an false discovery rate(FDR)correction adjustedP value considered statistically significant(P<0.001,fold change 2.69).Reactome functional analysis revealed eight biological pathways significantly different between dysosmic and normosmic patients(P<0.05,FDR correction)including IL-4 and IL-13 signaling,IL-10 signaling,and rhodopsin-like ***:RNA sequencing of the superior turbinates in patients with CRSsNP can provide valuable information regarding biological pathways and genes involved in olfactory *** study supports literature suggesting that Type 2 inflammation may play a role in olfactory dysfunction in at least some patients with *** study also prompts questions regarding the role of IL-10,rhodopsin-like receptors,andIER3 in the pathogenesis of olfactory dysfunction.

关键词： chronic rhinosinusitis without nasal polyps olfactory dysfunction RNA sequencing

Comparison of trigeminal lateralization with differing stimulants

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World journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 66-69页

作者： Tiffany Chen Nicolas S.Poupore Michael C.Shih Thomas S.Edwards Shaun A.Nguyen zachary M.Soler Rodney j.Schlosser Department of Otolaryngology‐Head and Neck Surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA

Trigeminal-specific stimulants have been shown to activate different receptors preferentially and this likely accounts for variation in sensory *** is unclear whether trigeminal sensitivity is similar across different transient receptor potential(TRP)receptors or if dysfunction of different receptors results in differing patient ***,a prospective cohort study was conducted,consisting of trigeminal lateralization testing with three different stimulants(eucalyptol,isothiocyanate,acetic acid),olfaction testing with Sniffin'Sticks,and measurement of various patient‐reported outcome measures(PROMs).A total of 50 participants were enrolled across the olfactory *** TDI score was 27.1±8.3(range 7.0–39.5)with 38%normosmic and 62%*** trigeminal lateralization scores out of 20 in the overall cohort were 16.18(2.78)for eucalyptol,14.94(3.49)for mustard oil,and 15.28(3.68)for *** showed a significant correlation with threshold scores of Sniffin'Sticks.A significant correlation was found between acetic acid and various *** of the lateralization scores of the trigeminal stimulants correlated to each other significantly and there was no correlation to *** lack of correlation suggests that the measured sensitivity of one type of TRP receptor may not translate to similar sensitivity of the other *** investigations with TRPV1 and TRPA1 agonists are needed to corroborate our findings.

关键词： chemosensory olfaction trigeminal TRP receptor

Conservative management of spinal pathology with autologous conditioned serum: A systematic review of the literature

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World journal of Orthopedics 2024年第9期15卷 870-881页

作者： Christian j Rajkovic Matthew L Merckling Alyssa W Lee Galadu Subah Aryan Malhotra zachary D Thomas Sabrina L Zeller john V Wainwright Merritt D Kinon Department of Neurosurgery Westchester Medical CenterValhallaNY 10595United States

BACKGROUND Chronic inflammatory pain is associated with increased expression of interleukin(IL)-1,an inflammatory cytokine,and activity on its receptor(IL-1R).In response,the body produces IL-1R antagonist(IL-1Ra)to reduce this *** conditioned serum(ACS)is the only biologic therapy for spinal pathologies that enhances the action of endogenous IL-1Ra reserves to improve *** systematic review investigates the effectiveness of ACS in treating pain and dis-ability caused by spinal *** To evaluate the use of ACS as a conservative management option for spinal *** A systematic review of PubMed/Medline was performed to identify studies inve-stigating administration of ACS for treatment of any spinal *** Six articles were included,comprising 684 patients treated with epidural(n=133)or transforaminal(n=551)ACS *** had an average age of 54.0 years with slight female predominance(53.2%).The lumbar spine was most com-monly treated,with 567 patients(82.9%)receiving injections for lumbar radicu-lopathy(n=67),degenerative disc disease(DDD)(n=372),or spinal stenosis(n=128);cervical injections were performed in 109 patients(15.9%).Mean(SD)follow-up was 21.7(4.8)weeks from first ACS *** studies investigating mecha-nical lumbar and lumbar or cervical radicular pain reported significant pain re-duction at final follow-up compared to *** achieved comparable or su-perior results to lumbar epidural steroid *** events were reported in 21 patients(3.1%),with no serious adverse *** ACS injection is a safe and effective intervention for pain reduction in many spinal pathologies,including cervical and lumbar radiculopathies.

关键词： Spine Autologous conditioned serum Orthokine Regenokine Epidural steroid injection Interleukin-1 Inter-leukin-1 receptor antagonist

Visual ＂playback＂ of colorful signals in the field supports sensory drive for signal detectability

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Current Zoology 2018年第4期64卷 493-498页

作者： Alex R. gunderson Leo j. FLEISHMAN Manuel LEAL Department of Integrative Biology University of California Berkeley CA 94720 USA Department of Biology Union College Schenectady NY 12308 USA Division of Biological Sciences University of Missouri 105 Tucker Hall Columbia MO 65211 USA

Colorful visual signals are important systems for investigating the effects of signaling environ ments and receiver physiology on signal evolution as predicted by the sensory drive hypothesis. Support for the sensory drive hypothesis on color signal evolution is mostly based on document ing correlations between the properties of signals and habitat conditions under which the signals are given （i.e., a correlational approach） and less commonly on the use of mathematical models that integrate representations of visual environments, signal properties, and sensory systems （i.e., a functional approach）. Here, we used an experimental approach in the field to evaluate signal efficacy of colorful lizard throat fans called dewlaps that show geographic variation in the lizard Anolis cristatellus. We used a remote controlled apparatus to display ＂fake dewlaps＂ to wild lizards to test for adaptive divergence in dewlap brightness （i.e., perceived intensity） among populations in situ. We found evidence of local adaptation in dewlap brightness consistent with the sensory drive hypothesis. Specifically, dewlaps that had the brightness characteristics of local lizards were more likely to be detected than those with the brightness characteristics of nonlocal lizards. Our findings indicate that simplified mathematical representations of visual environments may allow robust estimates of relative detectability or conspicuousness in natural habitats. We have shown the feasibility of evaluating color signal efficacy experimentally under natural conditions and dem onstrate the potential advantages of presenting isolated components of signals to an intended re ceiver to measure their contribution to signal function.

关键词： Anolis color signal sensory drive signal evolution

Dysfunctional stem and progenitor cells impair fracture healing with age

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World journal of Stem Cells 2019年第6期11卷 281-296页

作者： Diane R Wagner Sonali Karnik zachary j.gunderson jeffery j Nielsen Alanna Fennimore Hunter j Promer jonathan W Lowery M Terry Loghmani Philip S Low Todd O McKinley Melissa A Kacena Matthias Clauss jiliang Li Department of Mechanical and Energy Engineering Indiana University-Purdue University IndianapolisIndianapolisIN 46202United States Department of Orthopaedic Surgery Indiana University School of MedicineIndianapolisIN 46202United States Department of Medicinal Chemistry and Molecular Pharmacology Purdue UniversityWest LafayetteIN 47907United States Department of Physical Therapy Indiana University- Purdue University IndianapolisIndianapolisIN 46202United States Division of Biomedical Science Marian University College of Osteopathic MedicineIndianapolisIN 46222United States Department of Chemistry Purdue UniversityWest LafayetteIN 47907 United States Richard L. Roudebush VA Medical Center IndianapolisIN 46202United States Department of Medicine Indiana University School of MedicineIndianapolisIN 46202United States Department of Biology Indiana University-Purdue University IndianapolisIndianapolisIN 46202United States

Successful fracture healing requires the simultaneous regeneration of both the bone and vasculature;mesenchymal stem cells (MSCs) are directed to replace the bone tissue, while endothelial progenitor cells (EPCs) form the new vasculature that supplies blood to the fracture site. In the elderly, the healing process is slowed, partly due to decreased regenerative function of these stem and progenitor cells. MSCs from older individuals are impaired with regard to cell number, proliferative capacity, ability to migrate, and osteochondrogenic differentiation potential. The proliferation, migration and function of EPCs are also compromised with advanced age. Although the reasons for cellular dysfunction with age are complex and multidimensional, reduced expression of growth factors, accumulation of oxidative damage from reactive oxygen species, and altered signaling of the Sirtuin-1 pathway are contributing factors to aging at the cellular level of both MSCs and EPCs. Because of these geriatric-specific issues, effective treatment for fracture repair may require new therapeutic techniques to restore cellular function. Some suggested directions for potential treatments include cellular therapies, pharmacological agents, treatments targeting age-related molecular mechanisms, and physical therapeutics. Advanced age is the primary risk factor for a fracture, due to the low bone mass and inferior bone quality associated with aging;a better understanding of the dysfunctional behavior of the aging cell will provide a foundation for new treatments to decrease healing time and reduce the development of complications during the extended recovery from fracture healing in the elderly.

关键词： Fracture healing Aging Bone Angiogenesis Mesenchymal stem cells Endothelial progenitor cells

Update in the treatment of intracranial atherosclerotic disease

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Stroke & Vascular Neurology 2020年第1期5卷 59-64页

作者： zachary R Barnard Michael j Alexander Neurosurgery Cedars-Sinai Medical CenterLos AngelesCaliforniaUSA

This review highlights the recent evolution of the imaging,medical management,surgical options and endovascular therapies for symptomatic intracranial atherosclerotic disease(ICAD).Recent imaging developments including optical coherence tomography and other modalities to assess the intracranial arteries for symptomatic ICAD are reviewed,not only to diagnose ICAD but to determine if ICAD plaques have any high-risk features for *** future developments in the treatment of ICAD are discussed,including the development of trackable drug-coated balloons for the cerebral circulation to treat primary or restenotic arteries,new iterations of self-expanding intracranial stents with easier delivery systems,and the re-examination of indirect surgical bypass techniques for *** addition to these important technological developments,however,is the evolving evidence regarding the best treatment window for these techniques and additional factors in medical management which can improve patient outcomes in this devastating pathology.

关键词： intracranial balloon arteries

Evolutionary diversity as a catalyst for biological discovery

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Integrative Zoology 2018年第6期13卷 616-633页

作者： zachary V.jOHNSON Larry j.YOUNG School of Biological Sciences Georgia Institute of TechnologyAtlantaGeorgiaUSA Center for Translational Social Neuroscience Silvio O.Conte Center for Oxytocin and Social CognitionDepartment of Psychiatry and Behavioral SciencesYerkes National Primate Research CenterEmory UniversityAtlantaGeorgiaUSA

The tremendous diversity of animal behaviors has inspired generations of scientists from an array of biological *** complement investigations of ecological and evolutionary factors contributing to behavioral evolution,modern sequencing,gene editing,computational and neuroscience tools now provide a means to discover the proximate mechanisms upon which natural selection acts to generate behavioral *** behaviors are motivated behaviors that can differ tremendously between closely related species,suggesting phylogenetic plasticity in their underlying biological *** addition,convergent evolution has repeatedly given rise to similar forms of social behavior and mating systems in distantly related *** behavioral divergence and convergence provides an entry point for understanding the neurogenetic mechanisms contributing to behavioral *** argue that the greatest strides in discovering mechanisms contributing to social behavioral diversity will be achieved through integration of interdisciplinary comparative approaches with modern tools in diverse species *** review recent advances and future potential for discovering mechanisms underlying social behavioral variation;highlighting patterns of social behavioral evolution,oxytocin and vasopressin neuropeptide systems,genetic/transcriptional“toolkits,”modern experimental tools,and alternative species systems,with particular emphasis on Microtine rodents and Lake Malawi cichlid fishes.

关键词： cichlids oxytocin and vasopressin social behavior toolkits voles