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Ashtekar-Kodama Gravity as a Classical and Quantum Extension of Loop Quantum Gravity

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Journal of Modern Physics 2024年第6期15卷 864-937页

作者： jan Helm Department of Electrical Engineering Technical University of Berlin Berlin Germany

This paper presents a new theory of gravity, called here Ashtekar-Kodama (AK) gravity, which is based on the Ashtekar-Kodama formulation of loop quantum gravity (LQG), yields in the limit the Einstein equations, and in the quantum regime a full renormalizable quantum gauge field theory. The three fundamental constraints (hamiltonian, gaussian and diffeomorphism) were formulated in 3-dimensional spatial form within LQG in Ashtekar formulation using the notion of the Kodama state with positive cosmological constant Λ. We introduce a 4-dimensional covariant version of the 3-dimensional (spatial) hamiltonian, gaussian and diffeomorphism constraints of LQG. We obtain 32 partial differential equations for the 16 variables Emn (E-tensor, inverse densitized tetrad of the metric) and 16 variables Amn (A-tensor, gravitational wave tensor). We impose the boundary condition: for large distance the E-generated metric g(E) becomes the GR-metric g (normally Schwarzschild-spacetime). The theory based on these Ashtekar-Kodama (AK) equations, and called in the following Ashtekar-Kodama (AK-) gravity has the following properties. • For Λ = 0 the AK equations become Einstein equations, A-tensor is trivial (constant), and the E-generated metric g(E) is identical with the GR-metric g. • When the AK-equations are developed into a Λ-power series, the Λ-term yields a gravitational wave equation, which has only at least quadrupole wave solutions and becomes in the limit of large distance r the (normal electromagnetic) wave equation. • AK-gravity, as opposed to GR, has no singularity at the horizon: the singularity in the metric becomes a (very high) peak. • AK-gravity has a limit scale of the gravitational quantum region 39 μm, which emerges as the limit scale in the objective wave collapse theory of Gherardi-Rimini-Weber. In the quantum region, the AK-gravity becomes a quantum gauge theory (AK quantum gravity) with the Lie group extended SU(2) = ε-tensor-group(four gen

关键词： Quantum Gravity Loop Quantum Gravity General Relativity Gravitational Wave Gauge Field Theory Graviton Hamiltonian Constraint Gaussian Constraint Diffeomorphism Constraint

Advancing immunosuppression in liver transplantation: A narrative review

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 441-448页

作者： Samuele Iesari Francesca Laura Nava Ilaria Elena Zais Laurent Coubeau Mariano Ferraresso Evaldo Favi jan Lerut General Surgery and Kidney Transplantation Fondazione IRCCS Ca’Granda Ospedale Maggiore Policlinico15 Via della Commenda20122 MilanItaly Institut de Recherche Expérimentale et Clinique Universitécatholique de Louvain10 Avenue Hippocrate1200 BrusselsBelgium Service de Chirurgie et Transplantation Abdominale Cliniques Universitaires Saint-Luc55 Avenue Hippocrate1200 BrusselsBelgium Department of Clinical Sciences and Community Health Universitàdegli Studi di Milano19 Via della Commenda20122 MilanItaly

Immunosuppression is essential to ensure recipient and graft survivals after liver transplantation(LT). However, our understanding and management of the immune system remain suboptimal. Current immunosuppressive therapy cannot selectively inhibit the graft-specific immune response and entails a significant risk of serious side effects, i.e., among others, de novo cancers, infections, cardiovascular events, renal failure, metabolic syndrome, and late graft fibrosis, with progressive loss of graft function. Pharmacological research, aimed to develop alternative immunosuppressive agents in LT, is behind other solidorgan transplantation subspecialties, and, therefore, the development of new compounds and strategies should get priority in LT. The research trajectories cover mechanisms to induce T-cell exhaustion, to inhibit co-stimulation, to mitigate non-antigen-specific inflammatory response, and, lastly, to minimize the development and action of donor-specific antibodies. Moreover, while cellular modulation techniques are complex, active research is underway to foster the action of T-regulatory cells, to induce tolerogenic dendritic cells, and to promote the function of B-regulatory cells. We herein discuss current lines of research in clinical immunosuppression, particularly focusing on possible applications in the LT setting.

关键词： Liver transplantation Immunosuppression Drug development Long-term results Clinical operational tolerance

Changes in the adult sex ratio of six duck species breeding populations over two decades

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Avian Research 2024年第2期15卷 202-210页

作者： Monika Homolkova Petr Musil Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova jan Zouhar Department of Ecology Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcka 129CZ-16521Prague–SuchdolCzech Republic Department of Terrestrial Ecology Norwegian Institute for Nature Research(NINA)PO Box 5685 TorgardenTrondheimN-7485Norway Department of Econometrics Faculty of Informatics and StatisticsUniversity of Economicsnam.W.Churchilla 4CZ-13067Prague 3Czech Republic

Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered *** with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction *** this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and *** evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in *** determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and *** the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early ***,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population.

关键词： Adult sex ratio Breeding population Population dynamics Red-listed species Waterfowl Winter weather conditions

Treatment of intermediate-risk prostate cancer with active surveillance in the routine care—Long-term outcomes of a prospective noninterventional study(HAROW)

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Current Urology 2024年第2期18卷 115-121页

作者： Lothar Weissbach Andreas Schwarte Edith A.Boedefeld jan Herden Health Research for Men GmbH BerlinGermany Urological practice Borken BorkenGermany Department of Urology Uro-OncologyRobot-Assisted and Reconstructive UrologyFaculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany PAN Clinic Urological practiceCologneGermany

Background:We report here the long-term outcomes of patients with intermediate-risk prostate cancer(PCa)treated with active surveillance(AS)in a daily routine *** andmethods:HAROW(2008–2013)was a noninterventional,health service research study investigating themanagement of localized PCa in a community setting.A substantial proportion of the study centers were office-based urologists.A follow-up examination of all intermediate-risk patients with AS was ***,cancer-specific,metastasis-free,and treatment-free survival rates,as well as reasons for discontinuation,were determined and ***:Of the 2957 patients enrolled,52 with intermediate-risk PCa were managed with AS and were available for *** median follow-up was 6.8 years(interquartile range,3.4–8.6 years).Seven patients(13.5%)died of causes unrelated to PCa,of whom 4 were under AS or under watchful *** patients(3.8%)developed *** estimated 8-year overall,cancer-specific,metastasis-free,and treatment-free survival rates were 85%(95%confidence interval[CI],72%–96%),100%,93%(95%CI,82%–100%),and 31%(95%CI,17%–45%),*** analysis,prostate-specific antigen density of≥0.2 ng/mL2 was significantly predictive of receiving invasive treatment(hazard ratio,3.29;p=0.006).Reasons for discontinuation were more often due to patient's or physician's concerns(36%)than due to observed clinical ***:Although survival outcome data for intermediate-risk patients managed with AS in real-life health care conditions were promising,rates of discontinuation were high,and discontinuation was often a patient's decision,even when the signs of disease progression were *** might be an indication of higher levels of mental burden and anxiety in this specific subgroup of patients,which should be considered when making treatment *** a psychological perspective,not all intermediate-risk patients are optimal candidates for A

关键词： Active surveillance Intermediate-risk prostate cancer HAROW study Conservative management Outcomes research

A New Version of the Lambda-CDM Cosmological Model, with Extensions and New Calculations

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Journal of Modern Physics 2024年第2期15卷 193-238页

作者： jan Helm Department of Electrical Engineering Technical University Berlin Berlin Germany

This article gives a state-of-the-art description of the cosmological Lambda-CDM model and in addition, presents extensions of the model with new calculations of background and CMB functions. Chapters 1-4 describe the background part of the model, i.e. the evolution of scale factor and density according to the Friedmann equations, and its extension, which results in a correction of the Hubble parameter, in agreement with new measurements (Cepheids-SNIa and Red-Giants). Based on this improved background calculation presented in chapters 5-9 the perturbation part of the model, i.e. the evolution of perturbation and structure according to the perturbed Einstein equations and continuity-Euler equations, and the power spectrum of the cosmic microwave background (CMB) is calculated with a new own code.

关键词： Lambda-DCM Friedmann Equations CMB Metric Perturbation Hubble Parameter

Importance of periphytic biofilms for carbon cycling in paddy fields:A review

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Pedosphere 2024年第1期34卷 36-43页

作者： Lei ZHOU Yonghong WU Junzhuo LIU Pengfei SUN Ying XU jan DOLFING Robert GMSPENCER Erik JEPPESEN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Zigui Three Gorges Reservoir Ecosystem Observation and Research Station of Ministry of Water Resources of the People's Republic of ChinaYichang 443605China College of Nanjing University of Chinese Academy of SciencesNanjing 211135China Faculty of Energy and Environment Northumbria UniversityNewcastle upon Tyne NE18QHUK Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee FL 32306USA Department of Ecoscience&Centre for Water Technology(WATEC) Aarhus UniversityAarhus DK-8000Denmark Sino-Danish Centre for Education and Research Beijing 100049China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and Implementation(EKOSAM)Middle East Technical UniversityAnkara 06800Turkiye Institute of Marine Sciences Middle East Technical UniversityMersin 33731Turkiye

Paddy fields play an important role in global carbon(C) cycling and are an important source of methane(CH_(4)) emissions. Insights into the processes influencing the dynamics of soil organic C(SOC) in paddy fields are essential for maintaining global soil C stocks and mitigating climate change. Periphytic biofilms composed of microalgae, bacteria, and other microorganisms are ubiquitous in paddy fields, where they directly mediate the transfer of elements at the soil-water interface. However, their contributions to C turnover and exchange have been largely neglected. Periphytic biofilms affect and participate in soil C dynamics by altering both abiotic(e.g., pH and redox potential) and biotic conditions(e.g., microbial community composition and metabolism). This review summarizes the contributions of periphytic biofilms to soil C cycling processes, including carbon dioxide fixation, SOC mineralization, and CH_(4) emissions. Future research should be focused on: i) the mechanisms underlying periphytic biofilm-induced C fixation and turnover and ii) quantifying the contributions of periphytic biofilms to soil C uptake, stabilization, and sequestration in paddy fields.

关键词： carbon fixation carbon mineralization carbon sequestration methane emission microbial aggregates soil organic carbon

Electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid Khan Dil Faraz Khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim Khan Saeed Ullah jan G.Murtaza Department of Physics University of Science&Technology BannuBannu28100Pakistan Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Laboratoire de Physique de La Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia Department of Physics Shaoxing UniversityShaoxing312000China Department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling Lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investigated comprehensively using first principles *** electronic properties were studied using PBE GGA,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious agreement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using PBE and TB-mBJ potentials while they show wide band gap semiconducting behavior by following hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to glimpse the contribution of orbitals of atoms in the formation of *** properties were studied by using BoltzTraP2 code employed to *** get enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric figure of merit(ZT)for all the samples YbMg_(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

A Room-Temperature Chloride-Conducting Metal-Organic Crystal[Al(DMSO)_(6)]Cl_(3) for Potential Solid-State Chloride-Shuttle Batteries

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Energy & Environmental Materials 2024年第1期7卷 107-113页

作者： Bing Wu jan Luxa Jiří Šturala Shuangying Wei Lukáš Děkanovský Abhilash Karuthedath Parameswaran Min Li Zdenek Sofer Department of Inorganic Chemistry University of Chemistry and Technology PragueTechnická 516628Prague Czech Republic

The growing demand for substitutes of lithium chemistries in battery leads to a surge in budding novel anion-based electrochemical energy storage,where the chloride ion batteries(CIBs)take over the *** application of CIBs is limited by the dissolution and side reaction of chloride-based electrode materials in a liquid *** the flipside,its solid-state electrolytes are scarcely reported due to the challenge in realizing fast Cl^(-)*** present study reports[Al(DMSO)_(6)]Cl_(3),a solid-state metal-organic material,allows chloride ion *** strong Al-Cl bonds in AlCl_(3)are broken down after coordinating of Al^(3+)by ligand DMSO,and Cl^(-)in the resulting compound is weakly bound to complexions[Al(DMSO)_(6)]^(3+),which may facilitate Cl^(-)*** partial replacement of Cl^(-)with PF_(6)^(-),the room-temperature ionic conductivity of as-prepared electrolyte is increased by one order of magnitude from 2.172×10^(-5)S cm^(-1)to 2.012×10^(-4)S cm^(-1).When they are assembled with Ag(anode)/Ag-AgCl(cathode)electrode system,reversible electrochemical redox reactions occur on both sides,demonstrating its potential for solid-state chloride ion *** strategy by weakening the bonding interaction using organic ligands between Cl^(-)and central metallic ions may provide new ideas for developing solid chloride-ion conductors.

关键词： [Al(DMSO)_(6)]Cl_(3) chloride-ion batteries ionic conductivity metal-organic solid-state electrolytes

Epidemiology of insertional and midportion Achilles tendinopathy in runners:A prospective cohort study

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Journal of Sport and Health Science 2024年第2期13卷 256-263页

作者： Wenbo Chen Kyra L.A.Cloosterman Sita M.A.Bierma-Zeinstra Marienke van Middelkoop Robert-jan de Vos Department of Orthopaedic Surgery and Sports Medicine Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of General Practice Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of Sports Medicine Huashan HospitalFudan UniversityShanghai 200040China

Background:Achilles tendinopathy(AT)is a common problem among *** is only limited evidence for risk factors for AT,and most studies have not defined the AT *** study has compared the incidence and risk factors between insertional AT and midportion AT,though they are considered *** study aimed to assess incidence and risk factors of AT based on data from a large prospective *** secondary aim was to explore differences in risk factors between insertional and midportion ***:Participants were recruited from among registered runners at registration for running *** were completed at baseline,1 month before the event,1 week before the event,and 1 month after the *** concerning demographics,training load,registered events,and running-related injuries were collected at *** follow-up questionnaires collected information about new injuries.A pain map was used to diagnose midportion and insertional *** primary outcome was the incidence of *** logistic regression analysis was applied to identify risk factors for the ***:We included 3379 participants with a mean follow-up of 20.4 *** incidence of AT was 4.2%.The proportion of insertional AT was 27.7%and of midportion AT was 63.8%;the remaining proportion was a combined type of insertional and midportion *** had a significantly higher incidence(5%,95%confidence interval(95%CI):4.1%-6.0%)than women(2.8%,95%CI:2.0%-3.8%).AT in the past12 months was the most predominant risk factor for new-onset AT(odds ratio(OR)=6.47,95%CI:4.27-9.81).This was similar for both subcategories of AT(insertional:OR=5.45,95%CI:2.51-11.81;midportion:OR=6.96,95%CI:4.24-11.40).Participants registering for an event with a distance of 10/10.55 km were less likely to develop a new-onset AT(OR=0.59,95%CI:0.36-0.97)or midportion AT(OR=0.47,95%CI:0.23-0.93).Higher age had a significant negative association with insertional AT(OR=0.97,95%CI:0.9

关键词： Achilles tendon injury Incidence Risk factor Running-related injury