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Journal of Bionic Engineering 2012年第3期9卷 336-342页

作者： M. z. Bendjaballah Biomedical Technology Department College of Applied Medical Sciences King Saud University Riyadh Saudi Arabia

A computer-aided design model for a fixed partial denture was constructed and used in a finite element analysis to study the overall load sharing mechanism between the fixed partial denture and oral structures while the denture base rested on the al- veolar ridge. To investigate the consequences of non-contact conditions, three additional models were generated incorporating a uniform clearance of 0.125 mm, 0.25 mm, and 0.5 mm, respectively. A 100 N static load located at the free end of the prosthesis was applied while the distal portion of the jaw was set fixed. The results show that whilst releasing the ridge almost entirely, the presence of the clearance drastically increased the load on the splinting teeth. A pull-out force on the canine tooth of about 44 N was computed, accompanied by a mesio-distal moment of about 500 ***. The combination of which was similar to the tooth extraction maneuver performed by the dentist. In contrast, the second premolar was found to bear a push-in force of almost 115 N. The first molar, though barely solicited in the contact condition, became substantially loaded in non-contact conditions, which validates the choice of sacrificing three teeth to support the denture.

关键词： finite element analysis splinted fixed partial denture hygienic space load transfer mechanism contact problem

A mathematical model for a disease outbreak considering waningimmunity class with nonlinear incidence and recovery rates

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Journal of Biosafety and Biosecurity

Journal of Biosafety and Biosecurity 2024年第3期6卷 170-180页

作者： Nursanti Anggriani Laz.rus Kalvein Beay Meksianis z.Ndii Fatuh Inayaturohmat Sanubari Tansah Tresna Department of Mathematics Universitas PadjadjaranSumedangIndonesia Department of Mathematics Universitas PattimuraMalukuIndonesia Department of Mathematics Universitas Nusa CendanaKupangIndonesia

In the spread of infectious diseases,intervention levels play a crucial role in shaping interactions between healthy and infected individuals,leading to a nonlinear transmission ***,the availability of medical resources limits the recovery rate of infected patients,adding further nonlinear dynamics to the healing *** research introduces novelty by combining nonlinear incidence and recovery rates alongside waning immunity in an epidemic *** present a modified SIRW-type model,examining the epidemic problem with these *** analysis,we explore conditions for non-endemic and co-existing cases based on the basic reproduction *** local stability of equilibria is verified using the Routh-Hurwitz.criteria,while global stability is assessed using Lyapunov functions for each ***,we investigate bifurcations around both non-endemic and co-existing ***,we give some simulations to support our analytical findings.

关键词： SIRW-type model Basic reproduction ratio Waning immunity Nonlinear incidence rate Nonlinear recovery rate Lyapunov functions Bifurcation

基于状态空间模型的激光再制造熔池温度控制系统

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表面工程与再制造 2024年第2期24卷 50-50页

作者： Yang G.-z. Liu T.-M. Song B.-X. Jiang X.-Y. Wang z.-S. Chen K.-Q. Liu W.-J. School of Mechanical Engineering Shenyang University of Technology Shenyang China

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种... 详细信息

激光再制造是用于再制造的一项重要技术,在航空航天、冶金、能源等领域应用广泛。然而,形状控制问题一直是制约其规模化和工业化应用的瓶颈。在激光再制造过程中,熔池温度是决定再制造件形状和性能稳定性的关键。基于此,本文提出了一种基于状态空间模型的激光再制造熔池温度实时在线控制方法,解决了控制机理模型难以建立和多变量约束的问题。

关键词：状态空间模型激光再制造熔池温度航空航天形状控制控制系统变量约束性能稳定性

Feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia

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Avian Research 2024年第3期15卷 336-344页

作者： Michael S.Lukubwe Daniel Velarde-Garcéz.Fernando Sequeira Susana Lopes Adrian J.F.K.Craig Vanessa A.Mata Department of z.ology and Entomology Rhodes UniversityMakhandaSouth Africa Department of Wildlife Management and Tourism Studies University of NamibiaKatima Mulilo CampusNamibia Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPortoPortugal CIBIO Centro de Investigação em Biodiversidade e Recursos GenéticosInBIO Laboratório AssociadoCampus de VairãoVairãoPortugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairãoVairãoPortugal

As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic *** to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be *** addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the ***,we used DNA metabarcoding on faecal samples to analyz. the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(***)in northeastern *** contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same *** this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod *** findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an *** observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal *** noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal *** study illustrates the dynamic foraging behavior of these specializ.d symbiotic birds,shedding light on their potential role in pest control services and disease transmission.

关键词： Commensalism Diet DNA metabarcoding Oxpeckers Parasitism Trophic ecology

Remodeling Tumor Immune Microenvironment by Using Polymer-Lipid-Manganese Dioxide Nanoparticles with Radiation Therapy to Boost Immune Response of Castration-Resistant Prostate Cancer

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Research 2024年第3期2023卷 83-96页

作者： Abdulmottaleb E.z.trini HoYin Lip Az.ar z.Abbasi Ibrahim Alradwan Taksim Ahmed Chunsheng He Jeffrey T.Henderson Andrew M.Rauth Xiao Yu Wu Advanced Pharmaceutics and Drug Delivery Laboratory Leslie Dan Faculty of PharmacyUniversity of TorontoM5S 3M2TorontoONCanada. Departments of Medical Biophysics and Radiation Oncology University of TorontoM5G 1L7TorontoONCanada.

Despite substantial progress in the treatment of castration-resistant prostate cancer (CRPC), including radiation therapy and immunotherapy alone or in combination, the response to treatment remains poor due to the hypoxic and immunosuppressive nature of the tumor microenvironment. Herein, we exploited the bioreactivity of novel polymer–lipid manganese dioxide nanoparticles (PLMDs) to remodel the tumor immune microenvironment (TIME) by increasing the local oxygen levels and extracellular pH and enhancing radiation-induced immunogenic cell death. This study demonstrated that PLMD treatment sensitiz.d hypoxic human and murine CRPC cells to radiation, significantly increasing radiation-induced DNA double-strand breaks and ultimately cell death, which enhanced the secretion of damage-associated molecular patterns, attributable to the induction of autophagy and endoplasmic reticulum stress. Reoxygenation via PLMDs also polariz.d hypoxic murine RAW264.7 macrophages toward the M1 phenotype, enhancing tumor necrosis factor alpha release, and thus reducing the viability of murine CRPC TRAMP-C2 cells. In a syngeneic TRAMP-C2 tumor model, intravenous injection of PLMDs suppressed, while radiation alone enhanced recruitment of regulatory T cells and myeloid-derived suppressor cells. Pretreatment with PLMDs followed by radiation down-regulated programmed death-ligand 1 and promoted the infiltration of antitumor CD8+ T cells and M1 macrophages to tumor sites. Taken together, TIME modulation by PLMDs plus radiation profoundly delayed tumor growth and prolonged median survival compared with radiation alone. These results suggest that PLMDs plus radiation is a promising treatment modality for improving therapeutic efficacy in radioresistant and immunosuppressive solid tumors.

关键词： RAW264.7 alone treatment

Analysis of the Impact of the Blaz.ko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri F.L.Sefyani A.Benhida z.Benkhaldoun K.Kolenberg K.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,France)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyz.d at different Blaz.ko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of FeⅡ(λ4923.921?)increases toward the minimum of the Blaz.ko cycle and decreases toward the maximum of the same Blaz.ko ***,we found that the Van Hoof effect is also modulated by the Blaz.ko ***,toward the minimum of the Blaz.ko cycle the Van Hoof effect is more visible and at the maximum of the Blaz.ko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blaz.ko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

ADAM8 inactivation retards intervertebral disc degeneration in mice

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Genes & Diseases 2024年第3期11卷 91-94页

作者： z.oz.en Tian Frances S.Shofer Mingyue Fan Alec z.Sandroni Lutian Yao Lin Han Ling Qin Motomi Enomoto-lwamoto Yejia z.ang Department of Physical Medicine&Rehabilitation Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA19146USA Department of Emergency Medicine Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA Department of Orthopedic Surgery Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPA 19104USA School of Biomedical Engineering Science&Health SystemsDrexel UniversityPhiladelphiaPA 19104USA Department of Orthopedics/Sports Medicine and Joint Surgery the First Hospital of China Medical UniversityShenyangLiaoning 110001China Department of Orthopedics University of Maryland School ofMedicineBaltimoreMD21201USA Section of Rehabilitation Medicine Corporal Michael J.Crescenz Veterans Affairs Medical CenterPhiladelphiaPA 19104USA

ADAM8 has been identified as the fibronectin-cleaving enz.me in human degenerative intervertebral disc(IVD)tissues.^(1)Increase of the active form of ADAM8 and its cleavage product,fibronectin fragment,correlated with an increased degree of IVD degeneration.1 Furthermore,fibronectin fragments have been shown to accelerate the progression of IVD degeneration.^(2)These findings suggest that ADAM8 may play a role in degenerative disc disease,a clinical problem with tremendous socioeconomic burdens in the United States.

关键词： ADAM8 degeneration intervertebral

美国25~64岁成年人的心血管疾病住院率及死亡率

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中华高血压杂志 2024年第1期32卷 96-96页

作者： Henry CM Oseran AS z.eng z.Dong H Wadhera rk 袁源(译) 郑武洪(审校) 不详

自2011年以来,美国心血管死亡率并未减少。人们越来越担心这样的形势反映了年轻人心血管健康的恶化。然而,该人群中急性心血管疾病住院率及死亡率负担的变化尚不明确。本研究从总体及不同社区收入水平,评估了25~64岁成年人心血管住院率... 详细信息

自2011年以来,美国心血管死亡率并未减少。人们越来越担心这样的形势反映了年轻人心血管健康的恶化。然而,该人群中急性心血管疾病住院率及死亡率负担的变化尚不明确。本研究从总体及不同社区收入水平,评估了25~64岁成年人心血管住院率及死亡率变化。方法:采用国家住院样本,在25~64岁成年人中,评估急性心肌缺血(acute myocardial infarction,AMI)、心力衰竭和缺血性脑卒中的年龄标准化年住院率及住院死亡率。

关键词：住院率心血管健康住院死亡率急性心血管疾病急性心肌缺血缺血性脑卒中心力衰竭收入水平

Decoloriz.tion of Direct Black 22 by Aspergillus ficuum

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Journal of Environmental Sciences 2001年第4期13卷 472-475页

作者： Dong, X.-j. Du, z.-y. Chen, z. Dept. of Biology/Environmental Sci. Wenzhou Normal College Wenzhou 325003 China

The decoloriz.tion of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decoloriz. Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decoloriz.d by 98.05% of the initial color in 24 h. The optimum pH and temperature of decoloriz.tion are 4.0 and 33 °C respectively. Aeration was quite beneficial to decoloriz.tion. Medium composition and the concentration of Direct Black 22 could affect the rate of decoloriz.tion. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decoloriz.tion of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation. The degradation experiment agree with the Michaelis-Menten kinetics equation.

关键词： Bioassay Biodegradation Color Concentration (process) Dyes pH Ultraviolet spectrophotometers

Discovery of new MAX-phase-like layered ternary carbide V_(8)P_(6)C:Crystal structure,thermal expansion,and elastic properties

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Journal of Materials Science & Technology 2024年第7期174卷 55-62页

作者： H.X.Chen L.Sheng z.L.z.ang X.C.Wen D.L.Yang X.Y.Ye P.Q.Dai School of Materials Science and Engineering Fujian University of TechnologyFuzhou 350118China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fuzhou 350118China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Due to the laminated structure,MAX phases and MAX-phase-like compounds possess outstanding dam-age tolerance capability with good thermal/electrical conductivity and other charming functional prop-erties,showing a bright future for structural-functional ***,a new MAX-phase-like ternary car-bide V_(8)P_(6)C with layered characteristics was *** to the alternate stacking of hexagonal-arranged M/A/X atom layers in MAX phases,V_(8)P_(6)C has a layered structure formed by a repeated stacking of the slabs consisting of V_(6)C-octahedrons and VP 6-distorted-octahedrons in three-atomic layers *** thermal expansion anisotropy was revealed,with the thermal expansion coefficients(TECs)along a-axis,c-axis,and the average value,equal toα_(a)=8.55(5)μK^(−1),α_(c)=10.23(5)μK^(−1),andα_(L)=9.14(5)μK^(−1),*** dilation along the c-axis was mainly dominated by out-plane V-P bonds be-tween layered *** to the pressure-dependent lattice parameters,the polycrystalline bulk modulus(B_(0)=185(9)GPa)and high compressibility anisotropy factor(B_(a)/B_(c)=1.64)was ***-while,the second-order elastic constants were calculated,and the elastic moduli,E=303 GPa,B=198 GPa,G=122 GPa,andν=0.246,were *** the weak connection between layer slabs by out-plane V1-P bond was revealed by the bond stiffness model,with a bond stiffness close to the M-A bond in MAX ***,good damage tolerance capability was predicted according to Paugh’s ratio(G/B=0.616)and Cauchy pressure(P_(a)=0 GPa,P_(c)=-7.5 GPa),even better than those of typical MAX *** discovery of V_(8)P_(6)C provides a new member of MAX-phase-like damage-tolerant ceramic with relatively low density,moderate thermal expansion,and anisotropic compressibility,and the unique lay-ered structure is inspiring for exploring new layered ternary ceramics.

关键词： New ternary carbide MAX phase Thermal expansion Elastic constants Anisotropy