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Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

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Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu H J weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

we study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. we consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

Designated critical habitats for *** species are not protected from climate and land-use change

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Geography and Sustainability 2024年第3期5卷 482-490页

作者： Aimee Delach Laura A.Nunes Alex Borowicz Theodore C.weber Center for Conservation Innovation Defenders of Wildlife113017th Street NWWashingtonD.C.20036United States

Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States(U.S.)Endangered Species Act(ESA).while this is an important protective mechanism,lands designated as critical habitat could still be subject to degradation and fragmentation if they are not also in a protected status that prioritizes biodiversity ***,most designations of critical habitat do not explicitly take climate change into *** objective of our study was to determine whether and to what extent critical habitats for species listed under the ESA are located within protected areas and areas previously identified as climate refugia or climate corridors,to inform management strategies to better conserve and recover these *** mapped the designated critical habitats of 153 ESA-listed species and measured their overlap with previously-identified areas of climate refugia and corridors(CRC),and also with lands designated as nature-protected by *** Survey’s Gap Analysis Project(GAP Status 1 or 2)and working lands with wildlife habitat potential(GAP Status 3).Only 18%of all designated critical habitat is located on lands that are both in CRC and nature-protected,and only 9%of species had over half of their designated critical habitats in such lands.84%of species hadwith these *** habitats may therefore not fulfill their essential role of helping imperiled species persist and recover.

关键词： Endangered Species Act Critical habitat Climate refugia Climate corridors Protected areas Biodiversity conservation

Determination of riding comfort on cycleways using a smartphone application

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 747-760页

作者： Anna Niska Leif Sjögren Peter Andrén Christian weber Tineke de Jong Aslak Fyhri Department of Infrastructure Maintenance Swedish National Road and Transport Research Institute(VTI)Linköping SE-58195Sweden Department of Safety and Behavior Institute of Transport EconomicsGaustadalleen 210349 OsloNorway

well maintained cycleways will encourage more people to cycle,as the condition of cycleways is important for the safety,accessibility and riding comfort of *** that,only a few models used to describe the quality of service for cyclists take the surface condition into *** measuring methods are needed to enable reliable and effective assessment of surface conditions,and measurable performance criteria related to the needs of cyclists should be *** purpose of this study has been to test the reliability and validity of using accelerometers in smartphones to assess the riding comfort on cycleways.A smartphone application converting three-dimensional accelerometer measurements into a single indicator for cycleways has been used to assess road surfaces in two field studies,in Sweden and Norway,*** studies assessed test sections of varying *** relate the measurements to subjective riding comfort assessments by cyclists,recruited cyclists collected quantitative data using the app,whilst also rating their perceived riding comfort by completing a *** were also related to standard road surface condition indicators,generated from a road surface tester equipped with 19 laser sensors:international roughness index(IRI),mega-and *** results show that it is possible to describe the unevenness of a cycleway using the technology present in smartphones.A software application can be used to collect and analyse data from the acceleration sensors in the phone,which can then be used to describe the riding comfort of *** is mainly the unevenness in the 50-1000 mm sizerange that create the greatest discomfort for cyclists,and intermittent vibrations are perceived as more uncomfortable than more evenly distributed ***,IRI is not a relevant measurement for describing the riding comfort of cyclists.

关键词： Cyclist Comfort Assessment Road surface measurement Smartphone application

Multiple myeloma survival in New South wales, Australia, by treatment era to 2020

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Cancer Biology & Medicine 2024年第8期21卷 703-711页

作者： Eleonora Feletto Qingwei Luo Anna Kelly Marianne weber David Goldsbury Katherine Barron Karen Canfell Xue Qin Yu The Daffodil Centre The University of SydneyA Joint Venture with Cancer Council NSWSydney NSW 2006Australia

Objective: Australia has relatively high multiple myeloma(MM) incidence and mortality rates. Advancements in MM treatment over recent decades have driven improvements in MM survival in high-income countries;however, reporting in Australia is limited. we investigated temporal trends in population-wide MM survival across 3 periods of treatment advancements in New South wales(NSw), ***: Individuals with an MM diagnosis in the NSw Cancer Registry between 1985 and 2015 with vital follow-up to 2020, were categorized into 3 previously defined treatment eras according to their diagnosis date(1985±1995, chemotherapy only;1996±2007, autologous stem cell transplantation;and 2008±2015, novel agents including proteasome inhibitors and immunomodulatory drugs). Both relative survival and cause-specific survival according to Fine and Gray's competing risks cumulative incidence function were calculated by treatment era and age at ***: Overall, 11,591 individuals were included in the study, with a median age of 70 years at diagnosis. Five-year relative survival improved over the 36-year(1985±2020) study period(31.0% in 1985±1995;41.9% in 1996±2007;and 56.1% in 2008±2015). For individuals diagnosed before 70 years of age, the 5-year relative survival nearly doubled, from 36.5% in 1985±1995 to 68.5% in 2008±2015. Improvements for those > 70 years of age were less pronounced between 1985±1995 and 1996±2007;however, significant improvements were observed for those diagnosed in 2008±2015. Similar overall and age-specific patterns were observed for causespecific survival. After adjustment for gender and age at diagnosis, treatment era was strongly associated with both relative and cause-specific survival(P with MM is improving in Australia with treatment advances. However, older age groups continue to experience poor survival outcomes with only modest improvements over time. Given the increasing prevalence of MM in

关键词： Multiple myeloma cancer epidemiology survival analysis competing risk analysis Australia

Superexchange and charge transfer in the nickelate superconductor La_(3)Ni_(2)O_(7) under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 1-8页

作者： wéi wú Zhihui Luo Dao-Xin Yao Meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Recently, a bulk nickelate superconductor La_(3)Ni_(2)O_(7) is discovered at pressures with a remarkable high transition temperature T_(c)~ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La_(3)Ni_(2)O_(7),by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d_(3z^(2)-r^(2)) and O-p_(z) orbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-d_(x^(2)-y^(2)) and O-p_(x)/p_(y) orbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the d_(x^(2)-y^(2)) and p_(x)/p_(y) orbitals, whereas the d_(3z^(2)-r^(2)) and p_(z) orbitals retain underdoped. we propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La_(3)Ni_(2)O_(7) superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth