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Potential of molecular chaperones for treating Alzheimer’s disease

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Neural Regeneration Research 2024年第11期19卷 2343-2344页

作者： Gefei Chen jan Johansson Department of Biosciences and Nutrition Karolinska InstitutetHuddingeSweden Department of Cell and Molecular Biology Uppsala UniversityUppsalaSweden

Alzheimer’s disease(AD)is the most prevalent form of dementia,i.e.,progressive memory loss and profound cognitive dysfunction,resulting in a considerable societal *** the neuropathological level,the brains of AD patients exhibit amyloid-β(Aβ)plaques,neurofibrillary tangles,and neuroinflammation(Sala Frigerio and De Strooper,2016).

关键词： Alzheimer inflammation Aβ

effects of acid deposition control in China:a review based on responses of subtropical forests

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Frontiers of environmental Science & engineering 2024年第6期18卷 115-126页

作者： Danni Xie Xiaodong Ge Lei Duan jan Mulder School of Land engineering Chang’an UniversityXi’an 710064China State Key Laboratory of environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Faculty of environmental Sciences and Natural Resource Management Norwegian University of Life SciencesBox 5003NO-1432ÅsNorway

For many decades,acid deposition used to pose a significant regional air pollution challenge in *** substantial emission control of anthropogenically derived sulfur and nitrogen containing gasses,both sulfur and nitrogen deposition,as well as the acid rain-affected area,have significantly decreased compared to their peak ***,particularly in the humid subtropics,are sensitive to acid deposition,as evidenced by soil acidification,sulfate and nitrate leaching in stream water,and elevated soil nitrous oxide *** in the total deposition of sulfur and nitrogen,caused a significant decline in sulfate and nitrate leaching from subtropical forest and subsequently in sulfate and nitrate concentrations in stream water,although there was about a 5-year *** delay may be attributed to the desorption of accumulated sulfate and continued elevated mineralization of accumulated nitrogen *** of nitrous oxide,a potent greenhouse gas,also declined in nitrogen-saturated subtropical forest soils,as soil water nitrate concentration ***,subtropical forests in China suffering from elevated acid deposition have begun to ***,the current levels of sulfur and nitrogen deposition continue to exceed the critical loads,i.e.,the assigned threshold levels in accordance with emission control policies,in more than 10%of the country’s land area,respectively,indicating remaining risks of acidification and ***,further emission reductions are urgently needed,also because they will help achieving goals related to air quality and nitrous oxide emissions.

关键词： Acidification Critical load Nitrous oxide Surface water chemistry Recovery

Weak influence of natural vegetation in urban green spaces compared to agricultural ecosystems on House Martin populations:Insights from nationwide citizen science data in the Czech Republic

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Avian Research 2024年第2期15卷 139-146页

作者： Denisa Dvorakova jan Sipos Josef Suchomel Department of Zoology FisheriesHydrobiology and ApicultureMendel University in BrnoZemedelska 161300BrnoCzech Republic

The House Martin(Delichon urbicum)is a common farmland bird species in the european landscape,yet its population numbers are currently in ***,it is not yet sufficiently explained why this long-term decline *** fill this gap in our knowledge,we investigated how land cover composition affects the abundance of House Martins on the landscape scale by using nationwide citizen science *** a generalised linear mixed-effect model(GLMM),we evaluated 12,094 records from the Czech Republic spanning *** analysis underscores the significance of land cover type in shaping House Martin *** specifically,our results indicate that within agricultural land covers“naturally managed arable lands”exhibited significant positive effect,while forests,orchards,and vineyards were deemed less favourable for House Martin *** urban land covers,we found a clear distinction in the impact on House Martin populations,with a positive effect observed in urban infrastructure,development areas,and post-industrial sites(i.e.,UrbanAreas),while an indifferent impact was noted within urban green spaces and landscaped areas(i.e.,GreenUrban).Notably,our findings suggest that the simple spatial,age,and species structure typical of forests in europe,and similarly,the uniform structure of parks and gardens,may be responsible for the decline in the abundance of the House *** advocate for the preservation or enhancement of urban greenery,expansion of natural vegetation in rural areas and adoption of ecological management practices in orchards and vineyards to mitigate further declines in House Martin populations.

关键词： Citizen science Habitat preferences House Martin Species distribution Urban and suburban landscape

Recurrent evolution of seaweed body plan complexity among photosynthetic eukaryotes

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Molecular Plant 2024年第7期17卷 999-1001页

作者： elisa S.Goldbecker Iker Irisarri jan de Vries Department of Applied Bioinformatics Institute for Microbiology and GeneticsUniversity of GottingenGoldschmidtstr.137077 GottingenGermany Section Phylogenomics Center for Molecular Biodiversity ResearchLeibniz Institute for the Analysis of Biodiversity Change(LIB)Museum of Nature HamburgMartin-Luther-King-Platz 320146 HamburgGermany Department of Applied Bioinformatics Campus Institute Data Science(CIDAS)University of GottingenGoldschmidtstr.137077 GottingenGermany Department of Applied Bioinformatics Gottingen Center for Molecular Biosciences(GZMB)University of GottingenGoldschmidtstr.137077 GottingenGermany

The evolutionary origin of multicellularity is an age-old question in biological *** studies have delved into the evolutionary processes that led to the evolution of multicellular life forms from unicellular *** beauty and the challenge about this topic are that evolution has brought forth various forms of multicellular life,multiple times independently,scattered across the evolutionary tree of *** to the challenge,multicellular organisms exist in a diversity of forms and complexities,and the mechanisms by which multicellularity emerged are also likely different between animals,algae,or fungi(Niklas and Newman,2020).Recently,Nelson et al.(2024)presented a large-scale comparative genomics study focused on particularly intricate multicellular organisms:macroalgae(seaweeds),which emerged independently in three distinct eukaryotic lineages-green algae(Chlorophyta),red algae(Rhodophyta),and brown algae(Phaeophyceae).

关键词： algae seaweed evolution

A new approach to pedestal differentiation for soil loss estimation-a case study from a burnt area in north-central Portugal

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Journal of Forestry Research 2024年第3期35卷 45-54页

作者： Frank G.A.Verheijen Martinho A.S.Martins Sergio A.Prats jan J.Keizer Centre for environmental and Marine Studies(CeSAM) Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal Mediterranean Institute for Agriculture Environment and Development(MED-CHANGE)Institute for Advanced Studies and ResearchUniversity of EvoraPolo da MitraAp.947006-554 EvoraPortugal GeoBiociencias Geotecnologias E Geoengenharias(GEOBIOTEC)Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal

Soil pedestals have long been used as qualitative indicators of soil splash *** rangelands,plant-capped pedestals,generally grass tussocks,have also been used to quantitatively estimate soil loss since the first half of the twentieth *** agricultural lands,forests,and bad-lands,stone-capped pedestals have been used as qualitative and semi-quantitative indicators of active,'extreme'*** work has been reported on using capstone pedestal data for quantifying soil *** postulate that three distinct capstone pedestal types may be present in any given location and that a detailed analysis of a pedestal height histogram may be used to recognize their *** analysis can subsequently inform if soil loss can be reliably estimated and if so,which of the existing methods using pedestal height data will provide more accurate *** three proposed capstone pedestal types are:(1)neo-pedestals formed underneath surface stones exposed by(partial)removal of the soil surface cover;(2)endo-pedestals formed underneath stones that were buried in the soil but have been exposed by erosion;and(3)phoenix-pedestals formed underneath stones from collapsed *** the pedestal height histogram of any given location,a skew to smaller heights may indicate the existence of endo-and/or phoenix-pedestals,which may be revealed as a bi-(or tri)modal distribution when using a smaller bin *** concept was applied to a case study where soil loss had been monitored for control plots and mulched plots during a 5-year period following wildfire in a eucalypt *** measured pedestal heights and used methods to quantitatively assess soil loss from soil pedestal data in the available *** pedestal data at the end of the 5-year period under or overestimated soil loss in the control treatment,with results ranging from 60 to 115%of measured soil loss,depending on the *** is postulated that phoenix-and endo-pedestals may be a driving fact

关键词： Soil pedestals Mulch Wildfire Soil erosion Char

Improved Belief Propagation Decoder for LDPC-CRC-Polar Codes with Bit-Freezing

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China Communications 2024年第7期21卷 135-148页

作者： Qasim jan Yin Chao Pan Zhiwen Muhammad Furqan Zakir Ali You Xiaohu National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211100China Department of Computer Science National University of Computer and Emerging Sciences Peshawar Campus 25100Pakistan Department of Software engineering Capital University of Science and Technology(CUST)Islamabad 44000Pakistan Department of Computer Sciences Bahria University Lahore CampusPakistan

Though belief propagation bit-flip(BPBF)decoding improves the error correction performance of polar codes,it uses the exhaustive flips method to achieve the error correction performance of CA-SCL decoding,thus resulting in high decoding complexity and *** alleviate this issue,we incorporate the LDPC-CRC-Polar coding scheme with BPBF and propose an improved belief propagation decoder for LDPC-CRC-Polar codes with bit-freezing(LDPCCRC-Polar codes BPBFz).The proposed LDPCCRC-Polar codes BPBFz employs the LDPC code to ensure the reliability of the flipping set,i.e.,critical set(CS),and dynamically update *** modified CS is further utilized for the identification of error-prone *** proposed LDPC-CRC-Polar codes BPBFz obtains remarkable error correction performance and is comparable to that of the CA-SCL(L=16)decoder under medium-to-high signal-to-noise ratio(SNR)*** gains up to 1.2dB and 0.9dB at a fixed BLeR=10-4compared with BP and BPBF(CS-1),*** addition,the proposed LDPC-CRC-Polar codes BPBFz has lower decoding latency compared with CA-SCL and BPBF,i.e.,it is 15 times faster than CA-SCL(L=16)at high SNR regions.

关键词： belief propagation bit-flipping concatenated codes LDPC-CRC-Polar codes polar codes

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

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