Lagrangian Particle Dispersion Models in the Grey Zone of Turbulence: Adaptations to FLEXPART-COSMO for Simulations at 1 km Grid Resolution.

Lagrangian particle dispersion models (LPDMs) are frequently used for regional-scale inversions of greenhouse gas emissions. However, the turbulence parameterizations used in these models were developed for coarse resolution grids, hence, when moving to the kilometre-scale the validity of these descriptions should be questioned. Here, we analyze the influence of the turbulence parameterization employed in the LPDM FLEXPART-COSMO model. Comparisons of the turbulence kinetic energy between the turbulence schemes of FLEXPART-COSMO and the underlying Eulerian model COSMO suggest that the dispersion in FLEXPART-COSMO suffers from a double-counting of turbulent elements when run at a high resolution of . Such turbulent elements are represented in both COSMO, by the resolved grid-scale winds, and FLEXPART, by its stochastic parameterizations. Therefore, we developed a new parametrization for the variations of the winds and the Lagrangian time scales in FLEXPART in order to harmonize the amount of turbulence present in both models. In a case study for a power plant plume, the new scheme results in improved plume representation when compared with in situ flight observations and with a tracer transported in COSMO. Further in-depth validation of the LPDM against methane observations at a tall tower site in Switzerland shows that the model's ability to predict the observed tracer variability and concentration at different heights above ground is considerably enhanced using the updated turbulence description. The high-resolution simulations result in a more realistic and pronounced diurnal cycle of the tracer concentration peaks and overall improved correlation with observations when compared to previously used coarser resolution simulations (at 7 km 7 km). Our results indicate that the stochastic turbulence schemes of LPDMs, developed in the past for coarse resolution models, should be revisited to include a resolution dependency and resolve only the part of the turbulence spectrum that is a subgrid process at each different mesh size. Although our new scheme is specific to COSMO simulations at resolution, the methodology for deriving the scheme can easily be applied to different resolutions and other regional models. Supplementary Information The online version contains supplementary material available at 10.1007/s10546-022-00728-3

A CO-based method to determine the regional biospheric signal in atmospheric CO₂

Regional-scale inverse modeling of atmospheric carbon dioxide (CORegional-scale inverse modeling of atmospheric carbon dioxide (CO₂) holds promise to determine the net CO₂ fluxes between the land biosphere and the atmosphere. This approach requires not only high fidelity of atmospheric transport and mixing, but also an accurate estimation of the contribution of the anthropogenic and background CO₂ signals to isolate the biospheric CO₂ signal from the atmospheric CO₂ variations. Thus, uncertainties in any of these three components directly impact the quality of the biospheric flux inversion. Here, we present and evaluate a carbon monoxide (CO)-based method to reduce these uncertainties solely on the basis of co-located observations. To this end, we use simultaneous observations of CO₂ and CO from a background observation site to determine the background mole fractions for both gases, and the regional anthropogenic component of CO together with an estimate of the anthropogenic CO/CO₂ mole fraction ratio to determine the anthropogenic CO₂ component. We apply this method to two sites of the CarboCount CH observation network on the Swiss Plateau, Beromünster and Lägern-Hochwacht, and use the high-altitude site Jungfraujoch as background for the year 2013. Since such a background site is not always available, we also explore the possibility to use observations from the sites themselves to derive the background. We contrast the method with the standard approach of isolating the biospheric CO₂ component by subtracting the anthropogenic and background components simulated by an atmospheric transport model. These tests reveal superior results from the observation-based method with retrieved wintertime biospheric signals being small and having little variance. Both observation- and model-based methods have difficulty to explain observations from late-winter and springtime pollution events in 2013, when anomalously cold temperatures and northeasterly winds tended to bring highly CO-enriched air masses to Switzerland. The uncertainty of anthropogenic CO/CO₂ emission ratios is currently the most important factor limiting the method. Further, our results highlight that care needs to be taken when the background component is determined from the site’s observations. Nonetheless, we find that future atmospheric carbon monitoring efforts would profit greatly from at least measuring CO alongside CO₂ holds promise to determine the net CO₂ fluxes between the land biosphere and the atmosphere. This approach requires not only high fidelity of atmospheric transport and mixing, but also an accurate estimation of the contribution of the anthropogenic and background CO₂ signals to isolate the biospheric CO₂ signal from the atmospheric CO₂ variations. Thus, uncertainties in any of these three components directly impact the quality of the biospheric flux inversion. Here, we present and evaluate a carbon monoxide (CO)-based method to reduce these uncertainties solely on the basis of co-located observations. To this end, we use simultaneous observations of CO₂ and CO from a background observation site to determine the background mole fractions for both gases, and the regional anthropogenic component of CO together with an estimate of the anthropogenic CO/CO₂ mole fraction ratio to determine the anthropogenic CO₂ component. We apply this method to two sites of the CarboCount CH observation network on the Swiss Plateau, Beromünster and Lägern-Hochwacht, and use the high-altitude site Jungfraujoch as background for the year 2013. Since such a background site is not always available, we also explore the possibility to use observations from the sites themselves to derive the background. We contrast the method with the standard approach of isolating the biospheric CO₂ component by subtracting the anthropogenic and background components simulated by an atmospheric transport model. These tests reveal superior results from the observation-based method with retrieved wintertime biospheric signals being small and having little variance. Both observation- and model-based methods have difficulty to explain observations from late-winter and springtime pollution events in 2013, when anomalously cold temperatures and northeasterly winds tended to bring highly CO-enriched air masses to Switzerland. The uncertainty of anthropogenic CO/CO₂ emission ratios is currently the most important factor limiting the method. Further, our results highlight that care needs to be taken when the background component is determined from the site’s observations. Nonetheless, we find that future atmospheric carbon monitoring efforts would profit greatly from at least measuring CO alongside CO₂

Experimental Analysis of a Wind-Turbine Rotor Blade Airfoil by means of Temperature-Sensitive Paint

Knowledge on the boundary-layer transition location at large chord Reynolds numbers is essential to evaluate the performance of airfoils designed for modern wind-turbine rotor blades. In the present work, a temperature-sensitive paint was used to systematically study boundary-layer transition on the suction side of a DU 91-W2-250 airfoil. The experiments were performed in the High-Pressure Wind Tunnel Göttingen at chord Reynolds numbers up to 12 million and angles of attack from −14 to 20°. The coefficients of airfoil lift, drag, and pitching moment were also obtained after integration of the pressure distributions measured on the surface and in the wake of the wind-tunnel model. The global information obtained via temperature-sensitive paint not only enabled the analysis of the change in the transition location with varying angle of attack and chord Reynolds number, but also provided an explanation for the evolution of the aerodynamic coefficients measured at stall and poststall conditions. The stability of the laminar boundary layers investigated in the experiments was analyzed according to linear stability theory. The results of the stability computations supported the experimentally observed variations in the transition location. The amplification factors of boundary-layer disturbances at transition were also determined by correlating the experimental and numerical results

PERBANDINGAN HASIL BELAJAR SISWA YANG MENGGUNAKAN E-BOOK DAN BUKU PAKET PADA MATERI EKOSISTEM DI KELAS X MAN BUNTET PESANTREN CIREBON

Berbagai bahan ajar atau sumber belajar yang ditawarkan kepada guru, kurang dimanfaatkan dengan baik, terutama oleh guru Biologi, sehingga pencapaian tujuan yang ditunjukkan siswa tidak sesuai dengan harapan. Bahan ajar eBook dan buku paket adalah alat pembelajaran yang dapat digunakan guru dalam menyampaikan materi Biologi. Bahan ajar eBook ini merupakan sumber belajar baru yang menyenangkan. eBook ini menyajikan mata pelajaran kepada siswa dengan memiliki kepraktisan dalam belajar. Berdasarkan hasil wawancara dengan salah satu guru Biologi dan siswa di MAN Buntet Pesantren Cirebon, proses pembelajaran Biologi di sekolah ini biasa menggunakan bahan ajar LKS dengan menyisipkan sesekali bahan ajar buku paket. Ini belum cukup untuk meningkatkan hasil belajar siswa. Penelitian ini bertujuan untuk mengkaji hasil belajar ekosistem yang menggunakan bahan ajar eBook dan pembelajaran dengan menggunakan bahan ajar buku paket. eBook sendiri merupakan buku yang berbentuk elektronik atau softcopy, sedangkan buku paket / pelajaran adalah tulisan seorang pengarang atau tim pengarang yang disusun dalam penelitian berdasarkan kurikulum atau tafsiran tentang kurikulum yang berlaku. Hasil belajar adalah tingkat penguasaan yang dicapai siswa dalam mengikuti program belajar mengajar sesuai dengan tujuan pendidikan yang ditetapkan melalui aspek kognitif. Ekosistem adalah kesatuan lingkungan hidup yang melakukan interaksi / timbal balik dengan lingkungannya. Penelitian ini dilakukan di MAN Buntet Pesantren Cirebon dengan populasi semua kelas X. Sampel kelas X.5 sebagai kelas eksperimen dan X.6 sebagai kelas kontrol. Penelitian ini dilakukan dari tanggal 23 april sampai 23 juni 2012, dengan menggunakan metode eksperimen dengan desain penelitian Randomized Control Group Pretest-posttest dan teknik pengumumpulan datanya dengan menggunakan test. Dari hasil penelitian diperoleh hasil belajar ekosistem siswa yang menggunakan bahan ajar eBook dan bahan ajar buku paket. Nilai rata-rata hasil belajar ekosistem, kelas eksperimen yang menggunakan baha ajar eBook adalah 54 pada pretest dan pada posttest adalah 74, sedangkan pada kelas kontrol dengan rata-rata 50 pada pretest dan pada posttest adalah 71. Dapat disimpulkan bahwa tidak terdapat perbedaan yang signifikan antara kelas yang menggunakan eBook dan buku paket. Kata Kunci : Hasil Belajar, Penggunaan eBook dan Buku Paket, Ekosiste

Protein trafficking through the endosomal system prepares intracellular parasites for a home invasion

Toxoplasma (toxoplasmosis) and Plasmodium (malaria) use unique secretory organelles for migration, cell invasion, manipulation of host cell functions, and cell egress. In particular, the apical secretory micronemes and rhoptries of apicomplexan parasites are essential for successful host infection. New findings reveal that the contents of these organelles, which are transported through the endoplasmic reticulum (ER) and Golgi, also require the parasite endosome-like system to access their respective organelles. In this review, we discuss recent findings that demonstrate that these parasites reduced their endosomal system and modified classical regulators of this pathway for the biogenesis of apical organelles

SUCLG2 identified as both a determinator of CSF Aβ1-42 levels and an attenuator of cognitive decline in Alzheimer's disease

Cerebrospinal fluid amyloid-beta 1-42 (Aβ1-42) and phosphorylated Tau at position 181 (pTau181) are biomarkers of Alzheimer's disease (AD). We performed an analysis and meta-analysis of genome-wide association study data on Aβ1-42 and pTau181 in AD dementia patients followed by independent replication. An association was found between Aβ1-42 level and a single-nucleotide polymorphism in SUCLG2 (rs62256378) (P = 2.5×10−12). An interaction between APOE genotype and rs62256378 was detected (P = 9.5 × 10−5), with the strongest effect being observed in APOE-ε4 noncarriers. Clinically, rs62256378 was associated with rate of cognitive decline in AD dementia patients (P = 3.1 × 10−3). Functional microglia experiments showed that SUCLG2 was involved in clearance of Aβ1-4

The fingerprint of the summer 2018 drought in Europe on ground-based atmospheric CO2 measurements

During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018.The UK sites were funded by the UK Department of Business, Energy and Industrial Strategy (formerly the Department of Energy and Climate Change) through contracts TRN1028/06/2015 and TRN1537/06/2018. The stations at the ClimaDat Network in Spain have received funding from the ‘la Caixa’ Foundation, under agreement 2010-002624

Genome-wide meta-analysis for Alzheimer's disease cerebrospinal fluid biomarkers

Amyloid-beta 42 (A beta 42) and phosphorylated tau (pTau) levels in cerebrospinal fluid (CSF) reflect core features of the pathogenesis of Alzheimer's disease (AD) more directly than clinical diagnosis. Initiated by the European Alzheimer & Dementia Biobank (EADB), the largest collaborative effort on genetics underlying CSF biomarkers was established, including 31 cohorts with a total of 13,116 individuals (discovery n = 8074; replication n = 5042 individuals). Besides the APOE locus, novel associations with two other well-established AD risk loci were observed; CR1 was shown a locus for A beta 42 and BIN1 for pTau. GMNC and C16orf95 were further identified as loci for pTau, of which the latter is novel. Clustering methods exploring the influence of all known AD risk loci on the CSF protein levels, revealed 4 biological categories suggesting multiple A beta 42 and pTau related biological pathways involved in the etiology of AD. In functional follow-up analyses, GMNC and C16orf95 both associated with lateral ventricular volume, implying an overlap in genetic etiology for tau levels and brain ventricular volume.Peer reviewe

New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele