检索结果-南通市图书馆

3D printing of patient-specific 316L–stainless–steel medical implants using fused filament fabrication technology: two veterinary case studies

在线全文

学校读者我要写书评

暂无评论

Bio-Design and manufacturing 2022年第4期5卷 808-815页

作者： j.m.Chacón P.j.núñez m.A.Caminero e.García-Plaza j.Vallejo m.Blanco escuela Técnica Superior de Ingeniería Industrial Universidad de Castilla-La ManchaAvdaCamilo JoséCela213071 Ciudad RealSpain Protresde Ingeniería y Soluciones C/Solana 60nave 313005 Ciudad RealSpain

Biomedical fracture fixation implants have complex sculptured geometries to adapt perfectly to fractured bones,making them difficult and expensive to manufacture with conventional machining methods. Fused filament fabrication(FFF) is a very popular Additive manufacturing technology that simplifies the manufacture of parts with complex geometries, making it ideal for the manufacture of customized medical implants.

关键词： steel fracture fused

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert j.Thomas m.Brandon Westover Can Zhang Department of neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Glycine-nitrate auto-combustion synthesis and magnetic properties of nanocrystalline ndAl_(x)Fe_(1-x)O_(3) perovskites

在线全文

学校读者我要写书评

暂无评论

journal of Rare earths 2023年第1期41卷 108-115页

作者： e.A.nforna Hj.m.ngantchou j.n.Ghogomu Department of Fundamental Science Higher Technical Teacher Training CollegeUniversity of BamendaP.O.Box 39BambiliCameroon Department of Chemistry Faculty of SciencesUniversity of DoualaP.O.Box 24157DoualaCameroon Department of Chemistry The University of BamendaP.O.Box 39BambiliCameroon Department of Chemistry University of DschangP.O.Box 67DschangCameroon

The effect of substitution of Fe^(3+) by Al^(3+) on the structure and magnetic properties of ndAl_(x)Fe_(1-x)O_(3) perovskite nano-powders(x=0.0,0.1,0.2,0.3,0.4,and 0.5) prepared by the glycine-nitrate auto-combustion method was *** samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(Sem),Fourier transform infrared spectroscopy(FT-IR),and energy dispersive X-ray spectroscopy(eDX).The magnetic properties of the samples were investigated using a vibrating sample magnetometer(VSm).The X-ray results for all samples reveal the formation of an orthorhombic perovskite phase(space group Pbnm) with no secondary *** crystallite sizes of the nanoparticles are found to decrease with increasing Al content,and are in the range of 53-38 *** images show spherical nanoparticles with *** FT-IR spectra confirm the presence of metal oxygen *** m-H loop of the pristine ndFeO_(3) sample is antiferromagnetic in the a b plane with weak ferromagnetism in the *** AI inclusions in the pristine polycrystal thereby creating magnetic vacancies is seen to influence the magnetic *** magnetic dilution results in enhanced magnetisation at low Al content;x=0.1,0.2(saturation magnetisation being 2.08 and 2.05 emu/g,respectively) compared to the pristine sample with a saturation magnetisation of 1.43 emu/g due to increased exchange *** dilution with nonmagnetic dopant induces the phase transition from weak ferromagnetic to paramagnetic depending on the impurity *** coercive field for ndFeO_(3) is found to be equal to 1950 Oe and decreases with *** findings lay a ground work for research in tuning magnetic properties and in spintronics with potential applications in data storage,switches and electronic devices.

关键词： Anti-ferromagnetism Weak ferromagnetism Orthorhombic ndAl_(x)Fe_(1-x)O_(3) Perovskite nanopowders magnetic dilution

Arctic sea-ice extent: no record minimum in 2023 or recent years

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.johannessen Tor I.Olaussen nansen Scientific Society BergenNorway nansen environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minim.m.each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. In general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

Algebraic and group treatments to nonlinear displaced number states and their nonclassicality features:A new approach

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2015年第6期24卷 334-340页

作者： n Asili Firouzabadi m K Tavassoly m j Faghihi Atomic and molecular Group Faculty of PhysicsYazd University The Laboratory of Quantum Information Processing Yazd University Physics and Photonics Department Graduate University of Advanced Technology

Recently, nonlinear displaced number states （nDnSs） have been manually introduced, in which the deformation function f（n） has been artificially added to the previously well-known displaced number states （DnSs）. Indeed, just a simple comparison has been performed between the standard coherent state and nonlinear coherent state for the formation of nDnSs. In the present paper, after expressing enough physical motivation of our procedure, four distinct classes of nDnSs are presented by applying algebraic and group treatments. To achieve this purpose, by considering the DnSs and recalling the nonlinear coherent states formalism, the nDnSs are logically defined through an algebraic consideration. In addition, by using a particular class of Gilmore-Perelomov-type of SU（1,1） and a class of SU（2） coherent states, the nDnSs are introduced via group-theoretical approach. Then, in order to examine the nonclassical behavior of these states, sub-Poissonian statistics by evaluating mandel parameter and Wigner quasi-probability distribution function associated with the obtained nDnSs are discussed, in detail.

关键词： displaced number state nonlinear coherent state Wigner function nonclassical state

emerging role of A-kinase anchoring protein 5 signaling in reward circuit function

在线全文

学校读者我要写书评

暂无评论

neural Regeneration Research 2025年第10期20卷 2913-2914页

作者： William j.Flerlage mark L.Dell’Acqua Brian m.Cox Fereshteh S.nugent Uniformed Services University of the Health Sciences Department of Pharmacology and Molecular TherapeuticsBethesdaMDUSA Department of Pharmacology University of Colorado School of MedicineAnschutz Medical CampusAuroraCOUSA

There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs).

关键词： function supporting

effect of sodium modification on microstructure and mechanical properties of thick-walled AlSi6Cu2.5 rheocast component

在线全文

学校读者我要写书评

暂无评论

Transactions of nonferrous metals Society of China 2010年第9期20卷 1643-1648页

作者： m.WeSSn n.e.AnDe RSSOn O.GRAnATH School of engineering Materials and Manufacturing-CastingJnkping University

The microstructure and tensile properties were investigated in a thick-walled section （approximately 45 mm×43 mm） of a rheocast component produced by the RheometalTm process. Due to the long solidification period of such components, it is expected that the A1-Si eutectic formed will be coarse. Therefore, sodium （na） was used as a modifying agent to reduce the coarseness of the eutectic. Tensile test bars were machined from three different sets of materials： 1） non-modified melt, 2） modified melt cast directly after na addition, and 3） modified melt cast 30 min after na addition. The alloy used was a secondary AlSi6Cu2.5 alloy （STenAL Rheol）, specially developed for rheocasting. The material was studied in the as-cast condition as well as after a T6 heat treatment. The results show that the Al-Si eutectic is significantly refined by the na addition, even after a fading time of 30 min. However, it is observed that the na modification generally has a detrimental effect on the mechanical properties, despite the structure refinement. This is especially true in the T6 heat treated condition, where the yield strength is reduced by more than 30%. Some possible mechanisms for the degradation of mechanical performance are discussed.

关键词： rheocasting thick-walled component eutectic modification mechanical properties sodium Al alloys

Site Selective excitation and energy Transfer in LiKGdF_5 Crystal Co-doped with er^(3+) and Tb (3+)

在线全文

学校读者我要写书评

暂无评论

journal of Rare earths 2004年第1期22卷 22-26页

作者：尹民 Khaidukov n m Krupa j C Structure Research Laboratory Kurnakov Institute of General and Inorganic Chemistry Institut de Physique nucléaire

Crystals of LiKGdF 5∶er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and excitation spectra from er 3+ and Tb 3+ ions embedded in LiKGdF 5 were clearly separated. The lifetimes of the emitting levels 4S 3/2 of er 3+ and 5D 4 of Tb 3+ were also determined. Following the site selective spectroscopy study, the dominant energy transfer process from Tb 3+ to er 3+ in the crystal was then investigated via transient experiments.

关键词： optics condensed matter physics energy transfer luminescence LiKGdF 5∶er3+, Tb3+ rare earths

K-P-Burgers equation in negative ion-rich relativistic dusty plasma including the effect of kinematic viscosity

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2016年第10期25卷 215-221页

作者： A n Dev m K Deka j Sarma D Saikia n C Adhikary Department of mathematics Siksha ‘O' Anusandhan University Department of Applied Sciences Institute of Science and Technology Gauhati University Department of mathematics R G Baruah College Physical Sciences Division Institute of Advanced Study in Science and TechnologyVigyan Path Paschim Boragaon

The stationary solution is obtained for the K–P–Burgers equation that describes the nonlinear propagations of dust ion acoustic waves in a multi-component, collisionless, un-magnetized relativistic dusty plasma consisting of electrons, positive and negative ions in the presence of charged massive dust grains. Here, the Kadomtsev–Petviashvili(K–P) equation, threedimensional(3D) Burgers equation, and K–P–Burgers equations are derived by using the reductive perturbation method including the effects of viscosity of plasma fluid, thermal energy, ion density, and ion temperature on the structure of a dust ion acoustic shock wave(DIASW). The K–P equation predictes the existences of stationary small amplitude solitary wave,whereas the K–P–Burgers equation in the weakly relativistic regime describes the evolution of shock-like structures in such a multi-ion dusty plasma.

关键词： K–P–Burgers equation negative ion relativistic plasma reductive perturbation method