| 1. |
- Abdin, A., et al.
(författare)
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Solutions for construction of a lunar base : A proposal to use the spacex starship as a permanent habitat
- 2021
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Ingår i: Proceedings of the International Astronautical Congress, IAC. - : International Astronautical Federation, IAF.
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Konferensbidrag (refereegranskat)abstract
- Returning to the Moon and establishing a permanent human presence is the next step in human space exploration. This necessitates the development of lunar infrastructure up to this task. This contribution presents a framework for rapid, cost-efficient, and supporting construction of a permanent and modular lunar base within the scope of what will be technically and legally feasible today. The proposed concept uses the SpaceX Starship Human Landing System as the foundation for a lunar base. The Starship will be placed horizontally on the lunar surface and transformed into a habitable volume. A workforce of modular rovers will aid astronauts in the construction process, and an array of countermeasures are presented to protect the astronauts from the effects of exposure to radiation, lunar dust, and extended hypogravity. Psychological and psychosocial factors are included to enhance individual well-being and crew dynamics. Physical and cognitive workloads are defined and evaluated to identify effective countermeasures, including specific spacesuit requirements. The proposed construction activities are to be organized as a multi-national public-private partnership to establish an international authority, a concept that has been successful on Earth but has yet to be applied to space activities on a multi-national level. A roadmap incorporating each part of the construction from human and technical perspectives is outlined. Other aspects that are critical to mission success include the cultural significance of the project, legal aspects, budget, financing, and potential future uses of the base. These solutions rely mainly on existing technologies and limited modifications to the lunar lander vehicle, making it a viable solution for the construction of a lunar base in the near future.
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| 2. |
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| 3. |
- Schaetzl, Randall J., et al.
(författare)
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Approaches and challenges to the study of loess : Introduction to the Loess-Fest Special Issue
- 2018
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Ingår i: Quaternary Research. - : Cambridge University Press (CUP). - 0033-5894 .- 1096-0287. ; 89:3, s. 563-618
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- In September 2016, the annual meeting of the International Union for Quaternary Research's Loess and Pedostratigraphy Focus Group, traditionally referred to as a LoessFest, met in Eau Claire, Wisconsin, USA. The 2016 LoessFest focused on thin loess deposits and loess transportation surfaces. This LoessFest included 75 registered participants from 10 countries. Almost half of the participants were from outside the United States, and 18 of the participants were students. This review is the introduction to the special issue for Quaternary Research that originated from presentations and discussions at the 2016 LoessFest. This introduction highlights current understanding and ongoing work on loess in various regions of the world and provides brief summaries of some of the current approaches/strategies used to study loess deposits.
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| 4. |
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| 5. |
- Berglund, Erik, et al.
(författare)
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Evidence for Ca2+-regulated ATP release in gastrointestinal stromal tumors
- 2013
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Ingår i: Experimental Cell Research. - : Elsevier BV. - 0014-4827 .- 1090-2422. ; 319:8, s. 1229-1238
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Tidskriftsartikel (refereegranskat)abstract
- Gastrointestinal stromal tumors (GISTs) are thought to originate from the electrically active pacemaker cells of the gastrointestinal tract. Despite the presence of synaptic-like vesicles and proteins involved in cell secretion it remains unclear whether GIST cells possess regulated release mechanisms. The GIST tumor cell line GIST882 was used as a model cell system, and stimulus-release coupling was investigated by confocal microscopy of cytoplasmic free Ca2+ concentration ([Ca(2+)1](i)), flow cytometry, and luminometric measurements of extracellular ATP. We demonstrate that GIST cells have an intact intracellular Ca2+-signaling pathway that regulates ATP release. Cell viability and cell membrane integrity was preserved, excluding ATP leakage due to cell death and suggesting active ATP release. The stimulus-secretion signal transduction is at least partly dependent on Ca2+ influx since exclusion of extracellular Ca2+ diminishes the ATP release. We conclude that measurements of ATP release in GISTs may be a useful tool for dissecting the signal transduction pathway, mapping exocytotic components, and possibly for the development and evaluation of drugs. Additionally, release of ATP from GISTs may have importance for tumor tissue homeostasis and immune surveillance escape.
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| 6. |
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| 7. |
- Berglund, Erik, et al.
(författare)
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Intracellular concentration of the tyrosine kinase inhibitor imatinib in gastrointestinal stromal tumor cells.
- 2014
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Ingår i: Anti-Cancer Drugs. - 0959-4973 .- 1473-5741. ; 25:4, s. 415-22
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Tidskriftsartikel (refereegranskat)abstract
- Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm in the gastrointestinal tract. In most GISTs, the underlying mechanism is a gain-of-function mutation in the KIT or the PDGFRA gene. Imatinib is a tyrosine kinase inhibitor that specifically blocks the intracellular ATP-binding sites of these receptors. A correlation exists between plasma levels of imatinib and progression-free survival, but it is not known whether the plasma concentration correlates with the intracellular drug concentration. We determined intracellular imatinib levels in two GIST cell lines: the imatinib-sensitive GIST882 and the imatinib-resistant GIST48. After exposing the GIST cells to imatinib, the intracellular concentrations were evaluated using LC-MS (TOF). The concentration of imatinib in clinical samples from three patients was also determined to assess the validity and reliability of the method in the clinical setting. Determination of imatinib uptake fits within detection levels and values are highly reproducible. The GIST48 cells showed significantly lower imatinib uptake compared with GIST882 in therapeutic doses, indicating a possible difference in uptake mechanisms. Furthermore, imatinib accumulated in the tumor tissues and showed intratumoral regional differences. These data show, for the first time, a feasible and reproducible technique to measure intracellular imatinib levels in experimental and clinical settings. The difference in the intracellular imatinib concentration between the cell lines and clinical samples indicates that drug transporters may contribute toward resistance mechanisms in GIST cells. This highlights the importance of further clinical studies to quantify drug transporter expression and measure intracellular imatinib levels in GIST patients.
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| 8. |
- Peled, M., et al.
(författare)
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Baseline spirometry parameters as predictors of airway hyperreactivity in adults with suspected asthma
- 2021
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Ingår i: Bmc Pulmonary Medicine. - : Springer Science and Business Media LLC. - 1471-2466. ; 21
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Tidskriftsartikel (refereegranskat)abstract
- Background Methacholine challenge tests (MCTs) are used to diagnose airway hyperresponsiveness (AHR) in patients with suspected asthma where previous diagnostic testing has been inconclusive. The test is time consuming and usually requires referral to specialized centers. Simple methods to predict AHR could help determine which patients should be referred to MCTs, thus avoiding unnecessary testing. Here we investigated the potential use of baseline spirometry variables as surrogate markers for AHR in adults with suspected asthma. Methods Baseline spirometry and MCTs performed between 2013 and 2019 in a large tertiary center were retrospectively evaluated. Receiver-operating characteristic curves for the maximal expiratory flow-volume curve indices (angle beta, FEV1, FVC, FEV1/FVC, FEF50%, FEF25-75%) were constructed to assess their overall accuracy in predicting AHR and optimal cutoff values were identified. Results A total of 2983 tests were analyzed in adults aged 18-40 years. In total, 14% of all MCTs were positive (PC20 <= 16 mg/ml). All baseline spirometry parameters were significantly lower in the positive group (p < 0.001). FEF50% showed the best overall accuracy (AUC = 0.688) and proved to be useful as a negative predictor when applying FEF50% >= 110% as a cutoff level. Conclusions This study highlights the role of FEF50% in predicting AHR in patients with suspected asthma. A value of >= 110% for baseline FEF50% could be used to exclude AHR and would lead to a substantial decrease in MCT referrals.
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