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Screening outstanding mechanical properties and low lattice thermal conductivity using global attention graph neural network

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Energy and AI 2023年第4期14卷 360-370页

作者： Joshua Ojih alejandro rodriguez Jianjun Hu Ming Hu Department of Mechanical Engineering University of South CarolinaSC 29208United States of America Department of Computer Science and Engineering University of South CarolinaSC 29208United States of America

Mechanical and thermal properties of materials are extremely important for various engineering and scientific fields such as energy conversion and energy ***,the characterization of these properties via high throughput screening at the quantum level,although highly accurate,is inefficient and very time-and *** contrast,prediction at the classical level is highly efficient but less *** deploy scalable global attention graph neural network for accurate prediction of mechanical properties which bridge the gap between the accuracy at the quantum level and efficiency at the classical *** 10,158 elastic constants as training data,we trained the models on 5 mechanical properties,namely bulk modulus,shear modulus,Young’s modulus,Poisson’s ratio,and *** the trained model,we predicted 775,947 data in search of materials with ultrahigh *** further verify the recommended ultrahigh hardness materials by high precision first principles calculations,and we finally identify 20 structures with extreme hardness close to diamond,the hardest material in *** those,two super hard materials are completely new and have not been reported in literature so *** further recommend potential materials from bulk modulus prediction to search low lattice thermal conductivity,and we verify the thermal conductivity of 338 structures with first *** results demonstrate that one can find materials with extreme mechanical properties recommended by graph neural network and low thermal conductivity material from bulk modulus prediction with minimal first principles calculations of the structures(only 0.04%)in the large-scale materials pool.

关键词： Graph neural network Machine learning Mechanical properties Ultrahigh hardness Lattice thermal conductivity DFT calculations Novel material discovery

Efficiently searching extreme mechanical properties via boundless objective-free exploration and minimal first-principles calculations

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npj Computational Materials 2022年第1期8卷 1336-1347页

作者： Joshua Ojih Mohammed Al-Fahdi alejandro David rodriguez Kamal Choudhary Ming Hu Department of Mechanical Engineering University of South CarolinaColumbiaSC29208USA Materials Science and Engineering Division National Institute of Standards and TechnologyGaithersburgMD20899USA

Despite the machine learning(ML)methods have been largely used recently,the predicted materials properties usually cannot exceed the range of original training *** deployed a boundless objective-free exploration approach to combine traditional ML and density functional theory(DFT)in searching extreme material *** combination not only improves the efficiency for screening large-scale materials with minimal DFT inquiry,but also yields properties beyond original training *** use Stein novelty to recommend outliers and then verify using *** data are then added into the training dataset for next round *** test the loop of training-recommendation-validation in mechanical property *** screening 85,707 crystal structures,we identify 21 ultrahigh hardness structures and 11 negative Poisson’s ratio *** algorithm is very promising for future materials discovery that can push materials properties to the limit with minimal DFT calculations on only~1%of the structures in the screening pool.

关键词： extreme properties minimal

Million-scale data integrated deep neural network for phonon properties of heuslers spanning the periodic table

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npj Computational Materials 2023年第1期9卷 2155-2166页

作者： alejandro rodriguez Changpeng Lin Hongao Yang Mohammed Al-Fahdi Chen Shen Kamal Choudhary Yong Zhao Jianjun Hu Bingyang Cao Hongbin Zhang Ming Hu Department of Mechanical Engineering University of South CarolinaColumbiaSC 29208USA Theory and Simulation of Materials(THEOS) École Polytechnique Fédérale de LausanneCH-1015 LausanneSwitzerland Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Materials Science Technical University of DarmstadtDarmstadt 64287Germany Materials Science and Engineering Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Department of Computer Science and Engineering University of South CarolinaColumbiaSC 29208USA

Existing machine learning potentials for predicting phonon properties of crystals are typically limited on a material-to-materialbasis, primarily due to the exponential scaling of model complexity with the number of atomic species. We address this bottleneckwith the developed Elemental Spatial Density Neural Network Force Field, namely Elemental-SDNNFF. The effectiveness andprecision of our Elemental-SDNNFF approach are demonstrated on 11,866 full, half, and quaternary Heusler structures spanning 55elements in the periodic table by prediction of complete phonon properties. Self-improvement schemes including active learningand data augmentation techniques provide an abundant 9.4 million atomic data for training. Deep insight into predicted ultralowlattice thermal conductivity (<1 Wm^(−1) K^(−1)) of 774 Heusler structures is gained by p–d orbital hybridization analysis. Additionally, aclass of two-band charge-2 Weyl points, referred to as “double Weyl points”, are found in 68% and 87% of 1662 half and 1550quaternary Heuslers, respectively.

关键词： properties phonon spanning

HLA-DQ:Celiac disease vs inflammatory bowel disease

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World Journal of Gastroenterology 2018年第1期24卷 96-103页

作者： Marta Maia Bosca-Watts Miguel Minguez Dolores Planelles Samuel Navarro alejandro rodriguez Jesus Santiago Joan Tosca Francisco Mora Disease Department of the University Clinic Hospital of Valencia University of ValenciaValencia 46017Spain Histocompatibility Department of the Transfusion Center of the Valencian Community Valencia 46014Spain Pathology Department of the University Clinic Hospital of Valencia University of ValenciaValencia 46017Spain Digestive Disease Department of the Hospital Virgen del Castillo of Yecla Yecla 30510Spain Digestive Disease Department of the Hospital de Manises Valencia 46940Spain Digestive Disease Department of the University Clinic Hospital of Valencia University of ValenciaValencia 46017Spain

AIM To determine the genetic predisposition to celiacdisease(Ce D) in inflammatory bowel disease(IBD) patients by quantifying the frequency of Ce D-related human leucocyte antigen(HLA)(HLA-Ce D: HLA-DQ2 and-DQ8) in IBD patients globally, by type of IBD and gender, and by calculating the protective/risk contribution of these haplotypes in the development of the IBD *** We conducted a prospective study with IBD patients from our Unit. Clinical information was gathered and blood was tested for HLA-CeD. The control group was made up of unrelated Valencian organ ***1034 subjects were analyzed: 457 IBD [207 ulcerative coliti(UC) and 250 Crohn's disease(CD)] patients and 577 healthy controls. 39% of the controls and 34% of the patients had HLA-Ce D(P = 0.0852). HLA-DQ2 was less frequent in UC patients(P = 0.0287), and HLA-DQ8 in CD(P = 0.0217). In women with UC, the frequency of DQ2.5 cis(DQB1*02:01-DQA1*05:01) was reduced ≥ 50% [P = 0.0344; preventive fraction(PF) = 13%]. PFs(7%-14%) were obtained with all HLACe D haplotypes. HLA DQB1*02:02-DQA1*02:01(HLADQ2.2) was more frequent in CD patients with respect to controls(P = 0.001) and UC patients(etiological fraction = 15%).CONCLUSION HLA-CeD is not more frequent in IBD patients, with an even lower frequency of HLA-DQ2 and-DQ8 in UC and CD respectively. HLA-DQ2.5 confers protection from the development of UC, especially in women, and HLADQ8 does so for the appearance of CD. HLA-DQ2.2 is present in 34% of the CD patients and may constitute a genetic risk factor for CD development.

关键词： Genetic predisposition Celiac disease Inflammatory bowel disease Crohn's disease Human leucocyte antigen Ulcerative colitis

Inverse-designed photonic fibers and metasurfaces for nonlinear frequency conversion[Invited]

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Photonics Research 2018年第5期6卷 I0107-I0114页

作者： CHAWIN SITAWARIN WEILIANG JIN ZIN LIN alejandro W.rodriguez Department of Electrical Engineering Princeton UniversityPrincetonNew Jersey 08544USA John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMassachusetts 02138USA

Typically, photonic waveguides designed for nonlinear frequency conversion rely on intuitive and established principles, including index guiding and bandgap engineering, and are based on simple shapes with high degrees of symmetry. We show that recently developed inverse-design techniques can be applied to discover new kinds of microstructured fibers and metasurfaces designed to achieve large nonlinear frequency-conversion efficiencies. As a proof of principle, we demonstrate complex, wavelength-scale chalcogenide glass fibers and gallium phosphide three-dimensional metasurfaces exhibiting some of the largest nonlinear conversion efficiencies predicted thus far,e.g., lowering the power requirement for third-harmonic generation by 104 and enhancing second-harmonic generation conversion efficiency by 107. Such enhancements arise because, in addition to enabling a great degree of tunability in the choice of design wavelengths, these optimization tools ensure both frequency-and phase-matching in addition to large nonlinear overlap factors.

关键词： Inverse-designed photonic fibers and metasurfaces nonlinear frequency conversion

Effects of medium-and long-distance running on cardiac damage markers in amateur runners:a systematic review,meta-analysis,and metaregression

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Journal of Sport and Health Science 2021年第2期10卷 192-200页

作者： Jacobo A.Rubio-Arias Luis Andreu Luis Manuel Martinez-Aranda alejandro Martinez-rodriguez Pedro Manonelles Domingo J.Ramos-Campo Faculty of Sport Catholic University of San Antonio(UCAM)Murcia 30107Spain LFE Research Group Department of Health and Human PerformanceFaculty of Physical Activity and Sport Science-INEFUniversidad Politecnica de MadridMadrid 28040Spain International Chair of Sports Medicine Catholic University of San Antonio(UCAM)Murcia 30107Spain Neuroscience of Human Movement Research Group(Neuromove) Catholic University of San Antonio(UCAM)Murcia 30107Spain Faculty of Sciences University of AlicanteAlicante 03690Spain

Background:To finish an endurance race,athletes perform a vigorous effort that induces the release of cardiac damage *** are several factors that can affect the total number of these markers,so the aim of this review was to analyze the effect of endurance running races on cardiac damage markers and to identify the factors that modify the levels of segregation of these cardiac damage ***:A systematic search of PubMed,Web of Science,and the Cochrane Library databases was *** analysis included studies where the acute effects of running races on cardiac damage markers(troponin I and troponin T)were analyzed,assessing the levels of these markers before and after the ***:The effects of running races on troponin I(mean difference=0.0381 ng/mL)and troponin T(mean difference=0.0256 ng/mL)levels were *** ages(R^(2)=14.4%,p=0.033)and body mass indexes(R^(2)=14.5%,p=0.045)of the athletes had a significant interaction with troponin *** addition,gender,mean speed,time to finish the race,and type of race can affect the level of cardiac damage ***:Endurance running races induce the release of cardiac-damage markers that remain elevated for at least 24 h after the *** addition,young male athletes with high body mass indexes who perform races combining long duration and moderate intensity(i.e.,marathons)release the highest levels of cardiac damage *** should take into consideration these results in the diagnosis and treatment of patients admitted to the hospital days after finishing endurance running races.

关键词： Endurance races Troponin I Troponin T Ultra-endurance

Near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： alejandro Rodríguez-Castellanos Manuel Carbajal-Romero Norberto Flores-Guzmán J.Efraín Rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

Shift in microhabitat use as a mechanism allowing the coexistence of victim and killer carnivore predators

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Open Journal of Ecology 2012年第3期2卷 115-120页

作者： Maria Viota alejandro rodriguez Jose V.Lopez-Bao Francisco Palomares Department of Conservation Biology Estacion Biologica de Donana(CSIC)SevillaSpain Grimso Wildlife Research Station Department of EcologySwedish University of Agricultural SciencesRiddarhyttanSweden

It has been suggested that spatial heterogeneity is key to the coexistence at local spatial scales of subordinate and dominant predator species by allowing the former to shift to more protective habitats when the risk of intraguild predation exists. Here, we show how the smaller carnivore Egyptian mongoose (Herpestes ichneumon) may coexist on a local scale with its intraguild pre- dator, the Iberian lynx (Lynx pardinus), by using places with different microhabitat character- istics. We expect that mongooses living within lynx home ranges will use denser and more protective habitats when active in order to di- minish their risk of being killed by lynx com- pared to those living in areas similar in vege- tation and prey availability but where lynx are absent. The scrubland cover of points used by mongooses outside lynx areas, and that of points located within lynx areas but not used by mongooses, were significantly lower than, or similar to, cover of points used by mongooses within lynx areas. The probability of finding mon- goose tracks was constant across levels of scrubland cover when lynx were absent, but more mongoose tracks were likely to be found in thicker scrubland within lynx areas, especially if these areas were intensively used by lynx. This result agrees with the hypothesis on shifts in microhabitat use of subordinate carnivores to prevent fatal or risky encounters with dominant ones.

关键词： Carnivore Coexistence Egyptian Mongoose Iberian Lynx Interspecific Competition Intraguild Predation Microhabitat Shift Spatial Heterogeneity

Inverse-designed photonic fibers and metasurfaces for nonlinear frequency conversion [Invited]: publisher's note

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Photonics Research 2019年第4期7卷 493-493页

作者： Chawin Sitawarin Weiliang Jin Zin Lin alejandro W. rodriguez Department of Electrical Engineering Princeton University Princeton New Jersey 08544 USA John A. Paulson School of Engineering and Applied Sciences Harvard University Cambridge Massachusetts 02138 USA

This publisher’s note corrects the funding section ***. 6 , B82 [ CrossRef ] (2018).

关键词： Nonlinear optical fibers