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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

Stability Analysis and Performance Evaluation of Additive Mixed-Precision Runge-Kutta Methods

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Communications on Applied Mathematics and Computation 2024年第1期6卷 705-738页

作者： Ben Burnett Sigal Gottlieb zachary J.Grant Center for Scientific Computing and data Science Research UMass DartmouthNorth DartmouthMassachusettsUSA CSME Michigan State UniversityEast LansingMichiganUSA

Additive Runge-Kutta methods designed for preserving highly accurate solutions in mixed-precision computation were previously proposed and *** specially designed methods use reduced precision for the implicit computations and full precision for the explicit *** this work,we analyze the stability properties of these methods and their sensitivity to the low-precision rounding errors,and demonstrate their performance in terms of accuracy and *** develop codes in FORTRAN and Julia to solve nonlinear systems of OdEs and PdEs using the mixed-precision additive Runge-Kutta(MP-ARK)*** convergence,accuracy,and runtime of these methods are *** show that for a given level of accuracy,suitably chosen MP-ARK methods may provide significant reductions in runtime.

关键词： Mixed precision Runge-Kutta methods Additive methods Accuracy

Sensing the Heartbeat of China’s dynamic Economy in Yiwu

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China Today 2024年第4期73卷 35-38页

作者： zachary LUNdQUIST 不详

Over the last 30 years,China’s small commodity market has been a big driving force for economic growth,and the city of Yiwu is the largest small commodity market in *** stong vitality today gives us a picture into ho... 详细信息

关键词： commodity China. driving

does Ruxolitinib, in Comparison to Best Available Therapy (BAT), Improve Pruritis Symptoms in Patients with Polycythemia Vera?

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Journal of Biosciences and Medicines 2024年第3期12卷 35-43页

作者： zachary Samuel Thorogood Philadelphia College of Osteopathic Medicine Philadelphia USA

Polycythemia vera manifests as a myeloproliferative neoplasm associated with diverse symptoms, including aquagenic pruritis. This systematic review addresses the pressing need to enhance the understanding of the disease’s symptomatology and optimize treatment strategies for improved patient outcomes. The rarity and low prevalence of polycythemia vera underscore the importance of this investigation, as existing standard of care involves a multifaceted approach and significant healthcare costs. despite advancement in therapeutic options, persistent symptoms and resistance to first-line treatments pose challenges. Ruxolitinib has emerged as a promising intervention, demonstrating clinically significant improvement for patients. This systematic review appraises three randomized controlled trials, shedding light on the efficacy of ruxolitinib and its potential to ameliorate pruritis symptoms in symptomatic patients.

关键词： Polycythemia Vera Ruxolitinib Pruritis

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

关键词： resonator thick free

How Agent Orange impacts prostate cancer risk,pathology,and treatment outcomes

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Current Urology 2024年第2期18卷 79-86页

作者： Awais Paracha Zohair Siddiqui Ali Abid Ekamjit deol Fatima Waheed zachary Hamilton Saint Louis University School of Medicine Saint LouisMOUSA Saint Louis University Saint LouisMOUSA New York Institute of Technology College of Osteopathic Medicine OldWestburyNYUSA department of Surgery Division of UrologySaint Louis University School of MedicineSaint LouisMOUSA

Between 2.6 and 3.8 million veterans served in Vietnam while the US military dispersed Agent Orange(AO),although the exact number of exposed individuals is *** Orange,an herbicide,is a known risk factor for various cancers,including sarcoma and leukemia,but less is known about its link with prostate cancer(PC).Prostate cancer is the most commonly diagnosed malignancy in men and the fifth most common cause of cancer-related death in men *** 2023,approximately 288,300 patients will be given a diagnosis of PC,and an estimated 34,700 fatalities will occur in the United ***,whether the pathologic characteristics of PC among those exposed to AO differ from those in the general population remains *** review synthesizes the literature regarding the impact of AO exposure on PC incidence and disease course.A comprehensive PubMed literature search of articles published beginning in 1950 was performed using the primary search terms“Agent Orange,”“TCdd,”and“tetrachlorodibenzodioxin”and the secondary search terms“prostate cancer”or“prostate neoplasm.”The search was limited to studies that focused on human participants and were published in *** authors thoroughly reviewed the retrieved articles for relevancy to the study aims:discussion of PC diagnosis,prognosis,or management among patients exposed to *** 108 studies identified in our search,13 were included in this systematic *** within studies concerning AO exposure with relation to PC incidence,age at diagnosis or treatment initiation,and PC severity seemed to be mixed and generally ***,the literature seems to indicate that there are no significant differences in survivorship between exposed and unexposed veterans who are given a diagnosis of *** these heterogeneous outcomes,the evidence does not encourage a significantly different approach to the diagnosis and management of PC for veterans exposed to *** shouldmake case-by-case decision

关键词： Agent Orange 2,3,7,8-Tetrachlorodibenzo-p-dioxin Prostate cancer Veterans

Impact of COVId-19-related lifestyle changes on diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第1期17卷 97-106页

作者： Bryce P.Johnson Yu-Guang He zachary M.Robertson Angeline Wang Rafael L.Ufret-Vincenty department of Ophthalmology UT Southwestern Medical CenterDallasTexas 75390-9057USA

AIM:To assess diabetic macular edema(dME)progression during the early phases of the COVId-19 pandemic,when severe societal restrictions raised the concern of possible deterioration of health in patients with systemic conditions,particularly those requiring frequent office ***:This is a multicenter retrospective chart review of 370 patients(724 eyes)with an established diagnosis of dME seen on 3 separate visits between January 2019 and July *** 1 was January 2019 to February 2020(considered pre-COVId-19),period 2 was March 2020 to december 2020(considered the height of the pandemic;highest level of pandemic-related clinical and societal regulations)and period 3 was January 2021 to July 2021(re-adjustment to the new“pandemic norms”).Main outcome measures included visual acuity,body mass index(BMI),blood pressure(BP),hemoglobin A1c(HbA1c),macular thickness,patient adherence to scheduled ophthalmology visits,and dME treatment(s)received at each *** facilitate measurement of macular thickness,each macula was divided into 9 Early Treatment diabetic Retinopathy Study(ETdRS)-defined macular sectors as measured by OCT ***:There was no change of BMI,systolic BP,and diastolic BP between any of the time ***1c showed a very small increase from period 1(7.6%)to period 2(7.8%,P=0.015)and decreased back to 7.6%at period 3(P=0.12).Macular thickness decreased for 100%of macular *** central macular thickness decreased across all 3 periods from 329.5 to 316.6μm(P=0.0045).After analysis of multiple variables including HbA1c,BMI,adherence to scheduled appointments,different clinic centers,and treatment interventions,there was no easily identifiable subgroup of patients that experienced the increase in ***:dME doesn’t worsen during the COVId-19 pandemic,instead sustaining a very small but statistically significant *** identifying a mechanism behind our findings is beyond the scope of this study,potential explanat

关键词： COVId-19 diabetic macular edema diabetic retinopathy optical coherence tomography

A Rare Case of Aortic Valve Endocarditis and Acute Meningitis due to Haemophilus influenzae

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Case Reports in Clinical Medicine 2024年第6期13卷 207-211页

作者： zachary M. Visinoni Justin d. Tse Christopher F. Pease department of Graduate Medical Education Internal Medicine Residency Sutter Roseville Medical Center Roseville USA Sutter Medical Group Roseville USA

HACEK organisms represent a rare but important group of causative pathogens in endocarditis. These bacteria have historically been associated with culture-negative endocarditis;however, modern laboratory techniques have made this less common. In this case, we present a 74-year-old man who presented with acute onset altered mentation, fever, and sepsis. He was ultimately found to have Haemophilus influenzae meningitis, cerebral empyema, aortic valve endocarditis, psoas myositis, and L2 - L3 diskitis with osteomyelitis. Although HACEK organisms are commonly found in the oropharynx and upper respiratory tract in humans, our patient did not report recent preceding dental or ENT procedures. H. influenzae is responsible for approximately 0.16% of all cases of bacterial endocarditis, representing a very limited subset. Although generally considered low virulent pathogens, this case demonstrates the unusual extent of infection from a HACEK organism, H. influenzae, causing aortic valve endocarditis as well as atypical non-cardiac sequelae, including acute meningitis.

关键词： HACEK Haemophilus influenzae Aortic Valve Endocarditis Bacterial Meningitis Cerebral Empyema

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Lessons from Baoxing

China Today 2024年第6期73卷 40-43页

作者： zachary G.LUNdQUIST 不详

IN the heart of Sichuan Province in southwest China lies a small county not many people know about,though the fluffy animals first discovered there scientifically are universally known and *** in Ya’an City is better known as the hometown of China’s giant pandas and today,it has also become a biodiversity hotspot and type locality for many endangered *** region has witnessed China’s journey in discovering,appreciating,and protecting wild*** April 22,a group of foreigners together with Chinese scholars,government officials,and panda lovers gathered in Baoxing to celebrate the 155th year of the scientific discovery of the giant panda and the 60th anniversary of the establishment of diplomatic relations between China and France.

关键词： southwest panda giant