13 research outputs found
Methyl or ethyl makes the difference: Synthesis and solid-state structure of 9,10-dialkyl-9,10-dihydro-9,10-digallaanthracenes
No full textJutzi P, Sielemann H, Neumann B, Stammler H-G. Methyl or ethyl makes the difference: Synthesis and solid-state structure of 9,10-dialkyl-9,10-dihydro-9,10-digallaanthracenes. INORGANICA CHIMICA ACTA. 2005;358(14):4208-4216.The donor-free 9, 10-dialkyl-9, 10-dihydro-9, 10-digallaanthracenes 1 (alkyl: methyl) and 2 (alkyl: ethyl) were prepared by reaction of 1,2-di(chloromercurio)benzene with the corresponding trialkylgallium. and isolated as colourless air- and moisture sensitive crystalline compounds. In the solid-state structure of 1, two slightly different monomers 1A and 1B are found, which form a dimer 1A and 1B held together by "medium" strong gallium arene pi-interactions. Further weak pi-interactions between 1A and 1A and 1B and 1B constitute a one-dimensional coordination polymer containing strands of the composition [center dot center dot center dot(1A center dot center dot center dot 1B)center dot center dot center dot(1B center dot center dot center dot 1A)center dot center dot center dot](n). In contrast, compound 2 crystallizes in the form of distinct molecular units without any further intermolecular pi-interactions. The molecular units possess D-2d symmetry and are built by strong n-interactions between two digallaanthracene monomers. Two symmetrical aryl group bridges between two gallium atoms are observed for the first time in the subunits of 2. By addition of a Lewisbase (THF, Pyridine) to 2, a monomeric planar digallaanthracene framework is restored, as proven by an X-ray crystal structure analysis of 2 center dot 2Py. The different structures of 1 and 2 are explained on the basis of steric effects. (c) 2005 Elsevier B.V. All rights reserved
Author Correction: The geology and evolution of the Near-Earth binary asteroid system (65803) Didymos
No full textBarnouin, Olivier S. et al.-- Full list of authors: Barnouin, Olivier; Ballouz, Ronald-Louis; Marchi, Simone; Vincent, Jean-Baptiste; Agrusa, Harrison; Zhang, Yun; Ernst, Carolyn M.; Pajola, Maurizio; Tusberti, Filippo; Lucchetti, Alice; Daly, R. Terik; Palmer, Eric; Walsh, Kevin J.; Michel, Patrick; Sunshine, Jessica M.; Rizos, Juan L.; Farnham, Tony L.; Richardson, Derek C.; Parro, Laura M.; Murdoch, Naomi; Robin, Colas Q.; Hirabayashi, Masatoshi; Kahout, Tomas; Asphaug, Erik; Raducan, Sabina D.; Jutzi, Martin; Ferrari, Fabio; Hasselmann, Pedro Henrique Aragao; CampoBagatin, Adriano; Chabot, Nancy L.; Li, Jian-Yang; Cheng, Andrew F.; Nolan, Michael C.; Stickle, Angela M.; Karatekin, Ozgur; Dotto, Elisabetta; Della Corte, Vincenzo; Mazzotta Epifani, Elena; Rossi, Alessandro; Gai, Igor; Deshapriya, Jasinghege Don Prasanna; Bertini, Ivano; Zinzi, Angelo; Trigo-Rodriguez, Josep M.; Beccarelli, Joel; Ivanovski, Stavro Lambrov; Brucato, John Robert; Poggiali, Giovanni; Zanotti, Giovanni; Amoroso, Marilena; Capannolo, Andrea; Cremonese, Gabriele; Dall'Ora, Massimo; Ieva, Simone; Impresario, Gabriele; Lavagn, Michèle; Modenini, Dario; Palumbo, Pasquale; Perna, Davide; Pirrotta, Simone; Tortora, Paolo; Zannoni, Marco; Rivkin, Andrew S.In this article the funding from the Spanish project PID2021-128062NB-I00 funded by MCIN/AEI
was omitted. The original article has been corrected.Peer reviewe
The Impact of Indoor Greenery and Clutter on Psychological Well-being, Learning-Ability, Social Interaction, Stress and Competence: A Study within the Framework of the Biophilia Hypothesis
No full textThis study examines the psychological effects of indoor greenery and visual clutter within the framework of the biophilia hypothesis, which posits an innate human tendency to seek connections with nature and natural elements, especially in times of spending more and more time indoors for work and leisure.
Specifically, this online study investigates how varying degrees of indoor vegetation and different levels of visual clutter influence subjective well-being, competence, and basic psychological needs, including autonomy, competence, and social connectedness.
By systematically varying the amount of greenery and clutter across images of indoor environments (e.g., tidy kitchens with plants vs. kitchens with many non-natural objects), the study explores how natural versus visually busy surroundings shape immediate psychological responses.
The findings of this study are expected to contribute to a deeper understanding of how biophilic and environmental design elements can enhance psychological functioning and support mental health in built environments, particularly in contexts where direct contact with nature is limited
Aquaporin 2 mutations in Trypanosoma brucei gambiense field isolates correlate with decreased susceptibility to pentamidine and melarsoprol
No full textThe predominant mechanism of drug resistance in African trypanosomes is decreased drug uptake due to loss-of-function mutations in the genes for the transporters that mediate drug import. The role of transporters as determinants of drug susceptibility is well documented from laboratory-selected Trypanosoma brucei mutants. But clinical isolates, especially of T. b. gambiense, are less amenable to experimental investigation since they do not readily grow in culture without prior adaptation. Here we analyze a selected panel of 16 T. brucei ssp. field isolates that (i) have been adapted to axenic in vitro cultivation and (ii) mostly stem from treatment-refractory cases. For each isolate, we quantify the sensitivity to melarsoprol, pentamidine, and diminazene, and sequence the genomic loci of the transporter genes TbAT1 and TbAQP2. The former encodes the well-characterized aminopurine permease P2 which transports several trypanocides including melarsoprol, pentamidine, and diminazene. We find that diminazene-resistant field isolates of T. b. brucei and T. b. rhodesiense carry the same set of point mutations in TbAT1 that was previously described from lab mutants. Aquaglyceroporin 2 has only recently been identified as a second transporter involved in melarsoprol/pentamidine cross-resistance. Here we describe two different kinds of TbAQP2 mutations found in T. b. gambiense field isolates: simple loss of TbAQP2, or loss of wild-type TbAQP2 allele combined with the formation of a novel type of TbAQP2/3 chimera. The identified mutant T. b. gambiense are 40- to 50-fold less sensitive to pentamidine and 3- to 5-times less sensitive to melarsoprol than the reference isolates. We thus demonstrate for the first time that rearrangements of the TbAQP2/TbAQP3 locus accompanied by TbAQP2 gene loss also occur in the field, and that the T. b. gambiense carrying such mutations correlate with a significantly reduced susceptibility to pentamidine and melarsoprol
Deep learning approach to predict sentinel lymph node status directly from routine histology of primary melanoma tumours
No full textAim: Sentinel lymph node status is a central prognostic factor for melanomas. However, the surgical excision involves some risks for affected patients. In this study, we therefore aimed to develop a digital biomarker that can predict lymph node metastasis non invasively from digitised H&E slides of primary melanoma tumours. Methods: A total of 415 H&E slides from primary melanoma tumours with known sentinel node (SN) status from three German university hospitals and one private pathological practice were digitised (150 SN positive/265 SN negative). Two hundred ninety-one slides were used to train artificial neural networks (ANNs). The remaining 124 slides were used to test the ability of the ANNs to predict sentinel status. ANNs were trained and/or tested on data sets that were matched or not matched between SN-positive and SN-negative cases for patient age, ulceration, and tumour thickness, factors that are known to correlate with lymph node status. Results: The best accuracy was achieved by an ANN that was trained and tested on unmatched cases (61.8% +/- 0.2%) area under the receiver operating characteristic (AUROC). In contrast, ANNs that were trained and/or tested on matched cases achieved (55.0% +/- 3.5%) AUROC or less. Conclusion: Our results indicate that the image classifier can predict lymph node status to some, albeit so far not clinically relevant, extent. It may do so by mostly detecting equivalents of factors on histological slides that are already known to correlate with lymph node status. Our results provide a basis for future research with larger data cohorts. (C) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Combining CNN-based histologic whole slide image analysis and patient data to improve skin cancer classification
No full textBackground: Clinicians and pathologists traditionally use patient data in addition to clinical examination to support their diagnoses. Objectives: We investigated whether a combination of histologic whole slides image (WSI) analysis based on convolutional neural networks (CNNs) and commonly available patient data (age, sex and anatomical site of the lesion) in a binary melanoma/nevus classification task could increase the performance compared with CNNs alone. Methods: We used 431 WSIs from two different laboratories and analysed the performance of classifiers that used the image or patient data individually or three common fusion techniques. Furthermore, we tested a naive combination of patient data and an image classifier: for cases interpreted as 'uncertain' (CNN output score <0.7), the decision of the CNN was replaced by the decision of the patient data classifier. Results: The CNN on its own achieved the best performance (mean +/- standard deviation of five individual runs) with AUROC of 92.30% +/- 0.23% and balanced accuracy of 83.17% +/- 0.38%. While the classification performance was not significantly improved in general by any of the tested fusions, naive strategy of replacing the image classifier with the patient data classifier on slides with low output scores improved balanced accuracy to 86.72% +/- 0.36%. Conclusion: In most cases, the CNN on its own was so accurate that patient data integration did not provide any benefit. However, incorporating patient data for lesions that were classified by the CNN with low 'confidence' improved balanced accuracy. (c) 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)
The Dynamical State of the Didymos System before and after the DART Impact
No full textNASA's Double Asteroid Redirection Test (DART) spacecraft impacted Dimorphos, the natural satellite of (65803) Didymos, on 2022 September 26, as a first successful test of kinetic impactor technology for deflecting a potentially hazardous object in space. The experiment resulted in a small change to the dynamical state of the Didymos system consistent with expectations and Level 1 mission requirements. In the preencounter paper, predictions were put forward regarding the pre- and postimpact dynamical state of the Didymos system. Here we assess these predictions, update preliminary findings published after the impact, report on new findings related to dynamics, and provide implications for ESA's Hera mission to Didymos, scheduled for launch in 2024 October with arrival in 2026 December. Preencounter predictions tested to date are largely in line with observations, despite the unexpected, flattened appearance of Didymos compared to the radar model and the apparent preimpact oblate shape of Dimorphos (with implications for the origin of the system that remain under investigation). New findings include that Dimorphos likely became prolate due to the impact and may have entered a tumbling rotation state. A possible detection of a postimpact transient secular decrease in the binary orbital period suggests possible dynamical coupling with persistent ejecta. Timescales for damping of any tumbling and clearing of any debris are uncertain. The largest uncertainty in the momentum transfer enhancement factor of the DART impact remains the mass of Dimorphos, which will be resolved by the Hera mission.The work presented here was supported in part by the DART mission, NASA Contract #80MSFC20D0004 to JHU/APL. Part of this work was supported by the Programme National de Planétologie (PNP) of CNRS-INSU cofunded by CNES, by CNES itself, and by the BQR program of the Observatoire de la Côte d'Azur. The ACROSS project is supported under the OSIP ESA CONTRACT No. 4000135299/21/NL/GLC/ov. This study makes use of data obtained by the Observing Working Group of the DART Investigation Team. Some simulations were performed on the ASTRA cluster administered by the Center for Theory and Computation, part of the Department of Astronomy at the University of Maryland. H.F.A. was supported by the French government, through the UCA J.E.D.I. Investments in the Future project managed by the National Research Agency (ANR) with the reference number ANR-15-IDEX-01. R.H.C. acknowledges that this material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under grant No. DGE 2040434. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. F.F. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon Europe research and innovation program (grant agreement No. 101077758). R.M. acknowledges that this work was supported by a NASA Space Technology Graduate Research Opportunities (NSTGRO) award, NASA contract No. 80NSSC22K1173. P.M. acknowledges support from the French space agency CNES and ESA. R.N. acknowledges support from NASA/FINESST (NNH20ZDA001N). Y.Z. acknowledges the support provided by NASA through grant HST-GO-17292 from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, under NASA contract NAS 5-26555. A.C.B., E.G., M.J., P.M., R.L.M., S.D.R., P.T., K.T., and M.Z. acknowledge funding support from the European Union's Horizon 2020 research and innovation program under grant agreement No. 870377 (project NEO-MAPP). The work of S.R.C, E.G.F, and S.P.N was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (#80NM0018D0004). E.G., R.L.M., M.Z., and P.T. wish to acknowledge Caltech and the NASA Jet Propulsion Laboratory for granting the University of Bologna a license to an executable version of MONTE Project Edition S/W. E.G., R.L.M., A.R., M.Z., and P.T. are grateful to the Italian Space Agency (ASI) for financial support through Agreement No. 2022-8-HH.0 in the context of ESA's Hera mission. M.J. and S.D.R. acknowledge support by the Swiss National Science Foundation (project number 200021 207359). J.M. acknowledges support from the DART Participating Scientist Program (#80NSSC21K1048). F.M. acknowledges financial support from grants PID2021123370OB-I00 and CEX2021-001131-S funded by MCIN/AEI/10.13039/501100011033. N.M. acknowledges funding support from the European Commission's Horizon 2020 research and innovation program under grant agreement No. 870377 (NEO-MAPP project) and support from the Centre National d'Etudes Spatiales (CNES), focused on the Hera space mission. L.P. was supported by an appointment to the NASA Postdoctoral Program at the NASA Jet Propulsion Laboratory, California Institute of Technology, administered by Oak Ridge Associated Universities under contract with NASA. P.P. and P.S. acknowledge support by the Grant Agency of the Czech Republic, grant 23-04946S. S.R.S. acknowledges support from the DART Participating Scientist Program, grant no. 80NSSC22K0318. D.S. acknowledges support of the France-USA Fulbright Commission while a Fulbright Visiting Scholar (2022–2023) at UC Berkeley and thanks Action Fédératrice Gaia of the Paris Observatory for financial support. G.T. acknowledges financial support from project FCE-1-2019-1-156451 of the Agencia Nacional de Investigación e Innovación ANII and Grupos I+D 2022 CSIC-Udelar (Uruguay). P.T., A.R., and M.Z. acknowledge financial support from Agenzia Spaziale Italiana (ASI, contract No. 2019-31-HH.0 CUP F84I190012600). J.M.T.-R. acknowledges support from the Spanish project PID2021-128062NB-I00 funded by MCIN/AEI
