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Dirac Quantum Beats in Extreme Relativistic Diffraction in Time

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Journal of Applied Mathematics and Physics 2022年第5期10卷 1711-1720页

作者： salvador godoy Physics Department Science Faculty Mexico Autonomous National University Mexico City Mexico

We solve the relativistic Dirac equation for the shutter problem. We prove that, at intermediate relativistic energies, the probability density oscillates in time in a similar way to the optical Fresnel oscillations in a straight edge. However, for extreme-relativistic beams, the Fresnel oscillations turn into quantum damped beats.

关键词： Dirac Shutter Problem Relativistic Diffraction in Time Quantum Beats

Transient Quantum Beat Oscillations in Extreme-Relativistic Diffraction in Time

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Journal of Modern Physics 2021年第1期12卷 1-9页

作者： salvador godoy Universidad Nacional Autónoma de México Facultad de Ciencias Física CDMX Coyoacán México

In the solution of the Klein-Gordon equation for the shutter problem, we prove that, at internuclear distances, a relativistic beam of Pi-mesons has a probability density which oscillates in time in a similar way to the spatial dependence in optical Fresnel diffraction from a straight edge. However, for an extreme-relativistic beam, the Fresnel oscillations turn into quantum damped beat oscillations. We prove that quantum beat oscillations are the consequence, at extreme-relativistic velocities, of the interference between the initial incident wave function, and the Green’s function in the relativistic shutter problem. This is a pure quantum relativistic phenomenon.

关键词： Quantum Beat Oscillations Relativistic Diffraction in Time

A Basis for Causal Scattering Waves, Relativistic Diffraction in Time Functions

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Journal of Modern Physics 2016年第10期7卷 1181-1191页

作者： salvador godoy Karen Villa Depto de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City Mexico

Relativistic diffraction in time wave functions can be used as a basis for causal scattering waves. We derive such exact wave function for a beam of Dirac and Klein-Gordon particles. The transient Dirac spinors are expressed in terms of integral defined functions which are the relativistic equivalent of the Fresnel integrals. When plotted versus time the exact relativistic densities show transient oscillations which resemble a diffraction pattern. The Dirac and Klein-Gordon time oscillations look different, hence relativistic diffraction in time depends strongly on the particle spin.

关键词： Diffraction in Time Relativistic Diffraction in Time Causal Scattering Basis Transient Quantum Processes

Theory of Conductivity in Semiconducting Single-Wall Carbon Nanotubes

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Journal of Modern Physics 2012年第10期3卷 1550-1555页

作者： Shigeji Fujita salvador godoy Akira Suzuki Departamento de Física Facultad de Ciencias Universidad Nacional Autónoma de México Mexico City Mexico Department of Physics Faculty of Science Tokyo University of Science Shinjuku-ku Japan Department of Physics University at Buffalo Buffalo USA

The conduction of a single-wall carbon nanotube depends on the pitch. If there are an integral number of carbon hexagons per pitch, then the system is periodic along the tube axis and allows “holes” (not “electrons”) to move inside the tube. This case accounts for a semiconducting behavior with the activation energy of the order of around 3 meV. There is a distribution of the activation energy since the pitch and the circumference can vary. Otherwise nanotubes show metallic behaviors (significantly higher conductivity). “Electrons” and “holes” can move in the graphene wall (two dimensions). The conduction in the wall is the same as in graphene if the finiteness of the circumference is disregarded. Cooper pairs formed by the phonon exchange attraction moving in the wall is shown to generate a temperature-independent conduction at low temperature (3 - 20 K).

关键词： Semiconducting SWNT Cartesian Unit Cell Model Cooper Pair Bloch Electron Dynamics

Gene transcription profiting of astheno-and normo-zoospermic sperm subpopulations

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Asian Journal of Andrology 2020年第6期22卷 608-615页

作者： Pedro Caballero-Campo Saul Lira-Albarran David Barrera Elizabeth Borja-Cacho Hector S godoy-Morales Claudia Rangel-Escareno Fernando Larrea Mayel Chirinos Department of Reproduction Biology National Institute of Medical Sciences and Nutrition Salvador ZubiranMexico City 14080Mexico Tambre Foundation Madrid 28002Spain Reproductive Medicine Unit Angeles del Ped regal HospitalMexico City 10700Mexico Computational Genomic and Integrative Biology Laboratory National Institute of Genomic MedicineMexico City 14610Mexico

Spermatozoa contain a repertoire of RNAs considered to be potential functional fertility *** this study,the gene expression of human sperm subpopulations with high(F1)and low(F2)motility from healthy normozoospermic(N)and asthenozoospermic(A)individuals was evaluated using RNA microarray followed by functional genomic analysis of differentially expressed *** from A-F1 versus N-F1,A-F2 versus N-F2,N-F1 versus N-F2,and A-F1 versus A-F2 comparisons showed a considerably larger set of downregulated genes in tests versus *** ontology(GO)analysis of A-F1 versus N-F1 identified 507 overrepresented biological processes(BPs),several of which are associated with sperm *** addition,gene set enrichment analysis of the same contrast showed 110 BPs,36 cellular comp on ents,and 31 molecular functions,several of which are involved in sperm motility.A leadi ng・edge analysis of selected GO terms resulted in several down regulated genes encoding to dyn eins and kin esins,both related to sperm ***,the predicted activation state of asthenozoospermia was increased,while fertility,cell movement of sperm,and gametogenesis were ***,several downregulated genes characteristic of the canonical pathway protein ubiquitination were involved in asthenozoospermia ***,GO analysis of A-F2 versus N-F2 did not identify overrepresented BPs,although the gene set enrichment analysis detected six enriched BPs,one cellular component,and two molecular ***,the results show differences in gene transcription between sperm subpopulations from asthenozoospermic and normozoospermic semen samples and allowed the identification of gene sets relevant to sperm physiology and reproduction.

关键词： asthenozoospermia male in fertility microarray sperm transcriptome

The Global Soil Mycobiome consortium dataset for boosting fungal diversity research

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Fungal Diversity 2021年第6期111卷 573-588页

作者： Leho Tedersoo Vladimir Mikryukov Sten Anslan Mohammad Bahram Abdul Nasir Khalid Adriana Corrales Ahto Agan Aída-M.Vasco-Palacios Alessandro Saitta Alexandre Antonelli Andrea C.Rinaldi Annemieke Verbeken Bobby P.Sulistyo Boris Tamgnoue Brendan Furneaux Camila Duarte Ritter Casper Nyamukondiwa Cathy Sharp César Marín D.Q.Dai Daniyal Gohar Dipon Sharmah Elisabeth Machteld Biersma Erin K.Cameron Eske De Crop Eveli Otsing Evgeny A.Davydov Felipe E.Albornoz Francis Q.Brearley Franz Buegger Genevieve Gates Geoffrey Zahn Gregory Bonito Indrek Hiiesalu Inga Hiiesalu Irma Zettur Isabel C.Barrio Jaan Pärn Jacob Heilmann-Clausen Jelena Ankuda John Y.Kupagme Joosep Sarapuu Jose G.Maciá-Vicente Joseph Djeugap Fovo József Geml Juha M.Alatalo Julieta Alvarez-Manjarrez Jutamart Monkai Kadri Põldmaa Kadri Runnel Kalev Adamson Kari A.Bråthen Karin Pritsch Kassim I.Tchan Kęstutis Armolaitis Kevin D.Hyde Kevin K.Newsham Kristel Panksep Lateef A.Adebola Louis J.Lamit Malka Saba Marcela Eda Silva Cáceres Maria Tuomi Marieka Gryzenhout Marijn Bauters Miklós Bálint Nalin Wijayawardene Niloufar Hagh-Doust Nourou S.Yorou Olavi Kurina Peter E.Mortimer Peter Meidl RHenrik Nilsson Rasmus Puusepp Rebeca Casique-Valdés Rein Drenkhan Roberto Garibay-Orijel Roberto godoy Saleh Alfarraj Saleh Rahimlou Sergei Põlme Sergey V.Dudov Sunil Mundra Talaat Ahmed Tarquin Netherway Terry W.Henkel Tomas Roslin Vladimir E.Fedosov Vladimir G.Onipchenko WAErandi Yasanthika Young Woon Lim Meike Piepenbring Darta Klavina Urmas Kõljalg Kessy Abarenkov Mycology and Microbiology Center University of TartuTartuEstonia Institute of Ecology and Earth Sciences TartuEstonia Department of Ecology Swedish University of Agricultural SciencesUppsalaSweden Department of Botany University of the PunjabQuaid-e-Azam CampusLahorePakistan Centro de Investigaciones en Microbiología y Biotecnología-UR(CIMBIUR) Facultad de Ciencias NaturalesUniversidad del RosarioBogotáColombia Grupo de Microbiología Ambiental y BioMicro Escuela de MicrobiologíaUniversidad de Antioquia UdeAMedellínColombia Department of Agricultural Food and Forest SciencesUniversity of PalermoPalermoItaly Royal Botanic Gardens SurreyUK Department of Biomedical Sciences University of CagliariCagliariItaly Research Group Mycology Department of BiologyGhent UniversityGhentBelgium Department of Biomedicine Indonesia International Institute for Life SciencesJakartaIndonesia Plant Pathology and Agricultural Zoology Research Unit Department of Plant ProtectionFaculty of Agronomy and Agricultural SciencesUniversity of DschangDschangCameroon Department of Ecology and Genetics Uppsala UniversityUppsalaSweden Eukaryotic Microbiology University of Duisburg-EssenEssenGermany Department of Biological Sciences and Biotechnology Botswana International University of Science and TechnologyPalapyeBotswana Natural History Museum of Zimbabwe BulawayoZimbabwe Institute of Botany Czech Academy of SciencesPrůhoniceCzech Republic Center for Yunnan Plateau Biological Resources Protection and Utilization College of Biological Resource and Food EngineeringQujing Normal UniversityQujingPeople’s Republic of China Department of Botany Jawaharlal Nehru Rajkeeya MahavidyalayaPondicherry UniversityPort BlairIndia British Antarctic Survey NERCCambridgeUK Natural History Museum of Denmark University of CopenhagenCopenhagenDenmark Department of Environmental Science Saint Mary’s UniversityHalifaxNSCanada Altai State University BarnaulRussia CSIRO Land and Water WembleyWAAustralia Department of N

Fungi are highly important biotic components of terrestrial ecosystems,but we still have a very limited understanding about their diversity and *** data article releases a global soil fungal dataset of the Global Soil Mycobiome consortium(GSMc)to boost further research in fungal diversity,biogeography and *** dataset comprises 722,682 fungal operational taxonomic units(OTUs)derived from PacBio sequencing of full-length ITS and 18S-V9 variable regions from 3200 plots in 108 countries on all *** plots are supplied with geographical and edaphic *** OTUs are taxonomically and functionally assigned to guilds and other functional *** entire dataset has been corrected by excluding chimeras,index-switch artefacts and potential *** dataset is more inclusive in terms of geographical breadth and phylogenetic diversity of fungi than previously published *** GSMc dataset is available over the PlutoF repository.

关键词： Soil fungi Global dataset PacBio sequencing Fungal richness