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Three- and Four-dimensional Generalized Pythagorean Numbers

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Advances in Pure Mathematics 2024年第1期14卷 1-15页

作者： Alfred wünsche Institute of Physics Humboldt University Berlin Germany

The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a2+b2=c2 with integers (a, b, c) are generalized to 3d-Pythagorean quadruples (a, b, c | d) of spatial geometry which satisfy the equation a2+b2+c2=d2 with integers (a, b, c, d). Rules for a parametrization of the numbers (a, b, c, d) are derived and a list of all possible nonequivalent cases without common divisors up to d2 is established. The 3d-Pythagorean quadruples are then generalized to 4d-Pythagorean quintuples (a, b, c, d | e) which satisfy the equation a2+b2+c2+d2=e2 and a parametrization is derived. Relations to the 4-square identity are discussed which leads also to the N-dimensional case. The initial 3d- and 4d-Pythagorean numbers are explicitly calculated up to d2, respectively, e2.

关键词： Number Theory Pythagorean Triples Tesseract 4-Square Identity diophantine Equation

Mucopolysaccharidosis typeⅢB:a current review and exploration of the AAV therapy landscape

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Neural Regeneration Research 2024年第2期19卷 355-359页

作者： Courtney J.Rouse Victoria N.Jensen Coy d.Heldermon Lacerta Therapeutics AlachuaFLUSA University of Florida College of Medicine GainesvilleFLUSA

Mucopolysaccharidoses typeⅢB is a rare genetic disorder caused by mutations in the gene that encodes for *** results in the aggregation of heparan sulfate polysaccharides within cell lysosomes that leads to progressive and severe debilitating neurological *** treatment options are expensive,limited,and presently there are no approved cures for mucopolysaccharidoses typeⅢ***-associated virus gene therapy has significantly advanced the field forward,allowing researchers to successfully design,enhance,and improve potential *** group recently published an effective treatment using a codon-optimized triple mutant adeno-associated virus 8 vector that restores N-acetyl-alpha-glucosaminidase levels,auditory function,and lifespan in the murine model for mucopolysaccharidoses typeⅢB to that seen in healthy ***,we review the current state of the field in relation to the capsid landscape,adeno-associated virus gene therapy and its successes and challenges in the clinic,and how novel adenoassociated virus capsid designs have evolved research in the mucopolysaccharidoses typeⅢB field.

关键词： adeno-associated virus central nervous system gene therapy heparan sulfate immune response mucopolysaccharidoses type IIIB N-acetyl-alpha-glucosaminidase newborn screening

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

Screening and identification of salt tolerance soybean varieties and germplasms

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Oil Crop Science 2024年第3期9卷 204-210页

作者： Chen L. Peng L. Ouyang w. Yao H. Ye Y. Shan Z. Cao d. Chen S. Yang Z. Huang Y. Han B. Sha A. Zhou X. Chen H. Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430062 China College of Agriculture Yangtze University Jingzhou 434000 China

Soil salinization is a globally prevalent abiotic environmental stress. The imbalance of ions caused by high concentrations of sodium chloride results in a 40% reduction in soybean yield. Soybean, as an important crop for soil quality improvement, necessitates the identification of salt-tolerant varieties and germplasms to effectively utilize and enhance saline-alkali land. In this study, we assessed the salt tolerance of 435 soybean varieties and germplasms during the seedling stage. Among them, Qihuang34, You2104, Hongzhudou, Pamanheidou, and Osage exhibited grade 1 salt tolerance rates surpassing other tested materials. Furthermore, Hongzhudou and Qihuang34 demonstrated higher salt tolerance during germination and emergence stages based on their elevated rates of emergence, salt tolerance index, chlorophyll content, and shoot fresh weights. Overall findings provide valuable resources for molecular breeding efforts aimed at developing salt-tolerant soybean varieties suitable for cultivation in saline-alkali soils. © 2024 the Oil Crop Research Institute, Chinese Academy of Agriculture Sciences

关键词： Germination and emergence stage Germplasms Salt tolerance Seedling stage Soybean Varieties

Visible light positioning: moving from 2d planes to 3d spaces [Invited]

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Chinese Optics Letters 2019年第3期17卷 27-35页

作者： E.w.Lam T.d.C.Little Electrical and Computer Engineering department Boston University

The global navigation satellite system(GNSS) is a well-established outdoor positioning system with industry-wide impact due to the multifaceted applications of navigation, tracking, and automation. At large, however, is the indoor equivalent. One hierarchy of solutions, visible light positioning(VLP) with its promise of centimeter-scale accuracy and widespread coverage indoors, has emerged as a viable, easy to configure, and inexpensive candidate. we investigate how the state-of-the-art VLP systems fare against two hard barriers in indoor positioning: the need for high accuracy and the need to position in the threedimensions(3d). we find that although most schemes claim centimeter-level accuracy for some proposed space or plane, those accuracies do not translate into a realistic 3d space due to diminishing field-of-view in 3d and assumptions made on the operating space. we do find two favorable solutions in ray–surface positioning and gain differentials. Both schemes show good positioning errors, low-cost potential, and single-luminaire positioning functionality.

关键词： Visible light positioning moving from 2d planes to 3d spaces [Invited]

Comparing the Structural Parameters of the Milky way to Other Spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第3期24卷 10-28页

作者： Jacob A.Guerrette Aleksandr V.Mosenkov dallin Spencer Zacory d.Shakespear department of Physics and AstronomyN283 ESCBrigham Young University ProvoUT 84602USA

The structural parameters of a galaxy can be used to gain insight into its formation and evolution *** this paper,we strive to compare the Milky way’s structural parameters to other,primarily edge-on,spiral galaxies in order to determine how our Galaxy measures up to the Local *** our comparison,we use the galaxy structural parameters gathered from a variety of literature sources in the optical and near-infrared wave *** compare the scale length,scale height,and disk flatness for both the thin and thick disks,the thick-to-thin disk mass ratio,the bulge-to-total luminosity ratio,and the mean pitch angle of the Milky way’s spiral arms to those in other *** conclude that many of the Milky way’s structural parameters are largely ordinary and typical of spiral galaxies in the Local Universe,though the Galaxy’s thick disk appears to be appreciably thinner and less extended than expected from zoom-in cosmological simulations of Milky way-mass galaxies with a significant contribution of galaxy mergers involving satellite galaxies.

关键词： Galaxy disk-galaxies fundamental parameters-Galaxy structure

Natural parasites in conjunction with behavioral and color traits explain male agonistic behaviors in a lizard

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Current Zoology 2024年第1期70卷 59-69页

作者： Rodrigo Megia-Palma dhanashree Paranjpe Robert d.Cooper Pauline Blaimont Barry Sinervo department of Biomedicine and Biotechnology Parasitology UnitUniversidad de Alcala(UAH)E-28805Alcala de HenaresSpain CIBio Centro de Investigagao em Biodiversidade e Recursos GeneticosInBIO Laboratorio AssociadoCampus de VairaoUniversidade do PortoP-4485-661 VairaoPortugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairaoP-4485-661 VairaoPortugal Rupa Rahul Bajaj Center for Environment and Art Empress Botanical GardensKavade MalaPuneIndia department of Ecology and Evolutionary Biology University of CaliforniaLos AngelesCA 90095USA department of Biology University of Houston Downtown1Main St.HoustonTX 77002USA department of Ecology and Evolutionary Biology University of CaliforniaSanta CruzCA 95064USA

Male competition conforms to a cost-benefit model,because while aggression may increase reproductive prospects,it can also increase the risk of *** hypothesize that an additional cost in aggressive males would be an increase in parasite load associated with a high energy investment into sexual *** of these infections,in turn,may downmodulate the level of host aggression via energetic *** staged dyadic male contests in the lab to investigate the relationships of multiple parasites with the agonistic behavior of lizard hosts,Sceloporus *** also included both color and behavioral traits from opponents in the analyses because(1)color patches of lizards may serve as intraspecific signals used by conspecifics to assess the quality of opponents,and(2)contests between male lizards fit classical models of escalated aggression,where lizards increase aggression displays in response to an opponent's *** results conform to our hypothesis because male lizards displayed more pushups when they had more ***,some parasites may modulate the levels of aggression because lizards infected by hematic coccidians performed fewer ***,lizards also displayed fewer pushups when both the chroma and size of the opponent's blue patch were *** results thus also supported the role of the blue patch of *** as a sexual armament,because it contributed to the deterrence of aggression from opponent *** revealed that natural parasitic infections in lizard hosts can contribute to their agonistic *** encourage future studies to account for parasites in behavioral testswithlizards.

关键词： Ixodes pacificus Lankesterella sexual selection social interactions ticks

Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants

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International Journal of Extreme Manufacturing 2024年第1期6卷 353-374页

作者： Amit Bandyopadhyay Indranath Mitra Sushant Ciliveri Jose d Avila william dernell Stuart B Goodman Susmita Bose w.M.Keck Biomedical Materials Research Laboratory School of Mechanical and Materials EngineeringWashington State UniversityPullmanWA 99164United States of America Veterinary Clinical Sciences College of Veterinary MedicineWashington State UniversityPullmanWA 99164United States of America department of Orthopedic Surgery Stanford University Medical CenterRedwood CityCA 94063United States of America

Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants.

关键词： Ti6Al4V load-bearing implants additive manufacturing 3d printing antibacterial performance

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.wang Y.Chen w.B.Yao C.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2d)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2d PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering