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Finding stable multi-component materials by combining cluster expansion and crystal structure predictions

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npj computational Materials 2023年第1期9卷 2137-2146页

作者： adam carlsson Johanna Rosen Martin Dahlqvist Materials Design Department of PhysicsChemistryand Biology(IFM)Linköping UniversitySE-58183 LinköpingSweden

A desired prerequisite when performing a quantum mechanical calculation is to have an initial idea of the atomic positions within an approximate crystal *** atomic positions combined should result in a system located in,or close to,an energy ***,designing low-energy structures may be a challenging task when prior knowledge is scarce,specifically for large multi-component systems where the degrees of freedom are close to *** this paper,we propose a method for identification of low-energy crystal structures within multi-component systems by combining cluster expansion and crystal structure predictions with density-functional theory *** structure prediction searches are applied to the Mo_(2)AlB_(2) and Sc2AlB_(2) ternary systems to identify candidate structures,which are subsequently used to explore the quaternary(pseudo-binary)(Mo_(x)Sc_(1–x))2AlB_(2) system through the cluster expansion formalism utilizing the ground-state search ***,we show that utilizing low-energy structures found within the cluster expansion ground-state search as seed structures within crystal structure predictions of(Mo_(x)Sc_(1–x))2AlB_(2) can significantly reduce the computational *** this combined approach,we not only correctly identified the recently discovered Mo_(4/3)Sc_(2/3)AlB_(2) i-MAB phase,comprised of in-plane chemical ordering of Mo and Sc and with Al in a Kagomélattice,but also predict additional low-energy structures at various *** result demonstrates that combining crystal structure prediction with cluster expansion provides a path for identifying low-energy crystal structures in multi-component systems by employing the strengths from both frameworks.

关键词： structure cluster crystal

Landmark learning by the Ozark zigzag salamander Plethodon angusticlavius

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current Zoology 2011年第4期57卷 485-490页

作者： adam L. cRANE Alicia MATHIS Department of Biology Missouri State University Springfield MO 65897 USA

Although salamanders have been shown to respond to classical conditioning, spatial learning has been largely unstudied. We tested whether salamanders could learn to locate foraging areas by using landmarks. We trained 10 salamanders Plethodon angusticlavius to use landmarks （small rocks） to locate patches within the arena containing food （blackworms Lumbriculus variegatus）. At the comers of each square testing arena were four plastic dishes, one containing blackworms and the other three empty. A rock was placed in front of the dish containing blackworms, and the location of the food-dish was randomly chosen for each training trial. A control group was also trained to feed on blackworms in the presence of a rock, but the rock was positioned randomly among the four dish locations so that the rock was not a reliable landmark for the worms. Although the length of the training period for individual salamanders varied （22-38 trainings per individual）, the mean number of trainings for salamanders in the control and experimental groups was equal （30 training trials）. During testing, no blackworms were present to eliminate any visual or chemical cues emanating directly from the prey. Individuals trained with the rock landmarks spent sig- nificantly more time in the area of the landmark than did control salamanders [current Zoology 57 （4）： 485-490, 2011].

关键词： Landmark learning Spatial learning Salamander learning Plethodon angusticlavius Beacon

Phylogenetic status of Pneumocystis from corticosteroid-treated gerbils

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Science china(Life Sciences) 2010年第10期53卷 1239-1246页

作者： RODNEY D adam Department of Medicine and Immunobiology University of Arizona College of Medicine

Pneumocystis spp. infect the lungs of multiple mammalian species and cause disease in immunosuppressed individuals. The Pneumocystis isolates that have been studied to date fall into two major clades, those from primates and those from rodents. Within each of these clades, different species have been described on the basis of host specificity and differences in sequence and morphology. Here, we demonstrate that dexamethasone immunosuppression consistently results in histologically apparent lung infection in gerbils (28/35 animals). Sequence analysis of the 18S, 5.8S and internal transcribed spacer regions of the rDNA and a portion of the mitochondrial large subunit rDNA demonstrated that this gerbil Pneumocystis is grouped with other rodent Pneumocystis spp., but is distinct from them. Our results suggest that gerbil Pneumocystis differs sufficiently from Pneumocystis species found in other rodents to be considered a separate species.

关键词： 5.8S rRNA gene gerbil internal transcribed spacers (ITS) mitochondrial large subunit (mtLS) rRNA gene 18S rRNA gene Pneumocystis

Use of coals and wastes in a co-gasification process aimed at producing hydrogen rich gas

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International Journal of coal Science & Technology 2022年第6期9卷 161-167页

作者： Rafal Gssior adam Smoliński Polish Mining Group Inc. KatowicePoland central Mining Institute KatowicePoland

The use of low-quality coals and flotoconcentrates is currently severely limited,and the problem of managing municipal waste from anthropogenic activities is currently a *** problems of reducing carbon dioxide emissions,utilizing the energy potential of waste and increasing its recycling have an impact on the costs of electricity *** the abundant streams of unused fuels,they can be considered as attractive energy materials,so environmentally-friendly and cost-effective options for their utilization should be developed.A study was conducted using steam co-gasification technology on selected coals,flotation concentrates and Refuse Derived Fuel(RDF)alternative *** low-quality coals were combined with RDF alternative fuel in a process aimed at hydrogen *** experiments produced gas with hydrogen concentrations ranging from 67%(vol.)to 68%(vol.)with low methane *** was observed that the addition of alternative fuels helped to increase the hydrogen concentration in *** was paid to the catalytic ability of the metal oxides contained in the fuel blend,with particular reference to K_(2)O and Al_(2)O_(3)and TiO_(2).

关键词： coal Hydrogen Flotation concentrate Refuse derived fuel catalytic capacity catalysts

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Light(Science & Applications) 2024年第2期13卷 267-282页

作者： adam Overvig Sander A.Mann Andrea Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Program Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad range of exciting developments in nanophotonics research and applications,leveraging spatially extended—yet locally patterned—resonant modes to control light with new degrees of *** conventional grating responses are elegantly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal ***,we introduce spatio-temporal coupled mode theory(STcMT),capable of elegantly capturing the key features of the resonant response of wavefront-shaping nonlocal *** framework can quantitatively guide nonlocal metasurface design while maintaining compatibility with local metasurface frameworks,making it a powerful tool to rationally design and optimize a broad class of ultrathin optical *** validate this STcMT framework against full-wave simulations of various nonlocal metasurfaces,demonstrating that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave *** also discuss how this model may shed physical insights into nonlocal phenomena in photonics and the functionality of the resulting *** a relevant example,we showcase STcMT’s flexibility by applying it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially

The Future of cosmology and the Role of Non-Linear Perturbations

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communications in Theoretical Physics 2012年第2期57卷 323-325页

作者： adam J.christopherson Astronomy Unit School of Mathematical SciencesQueen Mary University of LondonMile End RoadLondonE1 4NSUK

cosmological perturbation theory is a key tool to study the *** linear or first order theory is well understood,however,developing and applying the theory beyond linear order is at the cutting edge of current research in theoretical *** this article,I will describe some signatures of non-linear perturbation theory that do not exist at linear order,focusing on vorticity generation at second *** doing so,we discuss why this,among other features such as induced gravitational waves and non-Gaussianities,shows that cosmological perturbation theory is crucial for testing models of the universe.

关键词： cosmology perturbation theory non-linear

Liquid deposition photolithography for submicrometer resolution three-dimensional index structuring with large throughput

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Light(Science & Applications) 2013年第1期2卷 209-214页

作者： adam c Urness Eric D Moore Keith K Kamysiak Michael c cole Robert R McLeod Department of Electrical Engineering University of Colorado at BoulderBoulderCO 80309USA.

Photonic devices increasingly require three-dimensional control of refractive index,but existing fabrication methods such as femtosecond micromachining,multilayer lithography and bulk diffusion can only address a select scale range,are often limited in complexity or thickness and have low *** introduce a new fabrication method and polymeric material that can efficiently create mm^(3) optical devices with programmable,gradient index of refraction with arbitrary feature *** contrast of 0.1 is demonstrated,which is 100 times larger than femtosecond micromachining,and 20 times larger than commercial holographic *** is achieved by repetitive microfluidic layering of a self-developing photopolymer structured by projection *** process has the unusual property that total fabrication time for a fixed thickness decreases with the number of layers,enabling fabrication 10^(5) faster than femtosecond *** demonstrate the process by sequentially writing 100 layers to fabricate a mm thick waveguide array.

关键词： holographic photopolymers lithography photonic device fabrication single photon polymerization three-dimensional structuring

can a dam type of an alpine lake be derived from lake geometry?A negative result

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Journal of Mountain Science 2021年第3期18卷 614-621页

作者： adam EMMER Vojtěch cURIN University of Graz Institute of Geography and Regional ScienceCascade|The Mountain Processes and Mountain Hazards GroupGraz 8010Austria czech Academy of Sciences Prague 16500Czechia Global change Research Institute Czech University of Life Sciences PragueFaculty of Environmental SciencesBrno 60300Czechia

Glacial lake outburst floods(GLOFs)represent one of the most serious hazard and risk in deglaciating high mountain regions worldwide and the need for GLOF hazard and risk assessment is *** a consequence,numerous region-and nation-wide GLOF assessment studies have been published *** studies cover large areas and consider hundreds to thousands of lakes,prioritizing the hazard posed by ***,certain simplification is required for executing such studies,often resulting in neglecting qualitative characteristics which would need manual *** lake dam types(e.g.,bedrock-dammed,moraine-dammed)are often not distinguished,despite they control GLOF mechanism(dam overtopping/dam breach)and thus GLOF *** this study,we explore the potential of easily measurable quantitative characteristics and four ratios to approximate the lake dam *** dataset of 851 lakes of the cordillera Blanca suggests that while variances and means of these characteristics of individual lake types differ significantly(F-test,t-test),value distribution of different geometrical properties can’t be used for the originally proposed purpose along the *** only promising results are obtained for extreme values(selected bins)of the *** instance,the low width to length ratio indicates likely morainedammed lake while the high value of ratio indicating round-shape of the lake indicates increased likelihood of bedrock-dammed ***,we report a negative result of our experiment since there are negligible differences of relative frequencies in most of the bins along the spectra.

关键词： Alpine lake High mountain lake GLOFs Glacial lake Moraine-dammed Bedrock-dammed Negative result cordillera Blanca

current and emerging trends in prostate cancer immunotherapy

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Asian Journal of Andrology 2019年第1期21卷 6-11页

作者： adam Schatz Badar M Mian Division of Urology Albany Medical CollegeAlbany NY 12054USA.

There have been a number of recent developments in the treatment of castration-resistant prostate cancer which seek to exploit the hormonal ***,the castration-resistant prostate cancer remains a major challenge since this is the lethal and incurable phenotype which results in tens of thousands of deaths every *** has been emerging interest in utilizing anticancer immunotherapy in prostate cancer,especially since the development of *** other prostate cancer therapeutic vaccines including autologous and allogeneic vaccines,as well as viral vector-based vaccines,have demonstrated promising results in early trials.

关键词： prostate cancer immunotherapy hormonal axis