Статті в журналах: "Missing Xenon"

1

Ozima, Minoru. "Geophysics: Looking for missing xenon." Nature 321, no. 6073 (June 1986): 813–14. http://dx.doi.org/10.1038/321813a0.

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2

Sanloup, C. "Retention of Xenon in Quartz and Earth's Missing Xenon." Science 310, no. 5751 (November 18, 2005): 1174–77. http://dx.doi.org/10.1126/science.1119070.

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3

Brock, David S., and Gary J. Schrobilgen. "Synthesis of the Missing Oxide of Xenon, XeO2, and Its Implications for Earth’s Missing Xenon." Journal of the American Chemical Society 133, no. 16 (April 27, 2011): 6265–69. http://dx.doi.org/10.1021/ja110618g.

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4

RITTER, STEVE. "THE CASE OF THE MISSING XENON." Chemical & Engineering News Archive 89, no. 9 (February 28, 2011): 10. http://dx.doi.org/10.1021/cen-v089n009.p010a.

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5

Brock, David S., and Gary J. Schrobilgen. "ChemInform Abstract: Synthesis of the Missing Oxide of Xenon, XeO2, and Its Implications for Earth′s Missing Xenon." ChemInform 42, no. 32 (July 14, 2011): no. http://dx.doi.org/10.1002/chin.201132007.

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6

Maria, Naomi Sta, and David M. Eckmann. "Model Predictions of Gas Embolism Growth and Reabsorption during Xenon Anesthesia." Anesthesiology 99, no. 3 (September 1, 2003): 638–45. http://dx.doi.org/10.1097/00000542-200309000-00019.

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Background It is not readily obvious whether an intravascular bubble will grow or shrink in a particular tissue bed. This depends on the constituent gases initially present in the bubble, the surrounding tissue, and the delivered gas admixture. The authors used a computational model based on the physics of gas exchange to predict cerebrovascular embolism behavior during xenon anesthesia. Methods The authors estimated values of gas transport parameters missing from the literature. The computational model was used with those parameters to predict bubble size over time for a range of temperatures (18 degrees -39 degrees C) used during extracorporeal circulation. Results Bubble size over time is highly nonlinearly dependent on multiple factors, including diffusivity, solubility, gas partial pressures, magnitude of concentration gradients, vessel diameter, and temperature. Xenon- and oxygen-containing bubbles continue to grow during xenon delivery. Bubble volume doubles from 50 to 100 nl in approximately 3-68 min, depending on initial gas composition and bubble shape. Bubble growth and reabsorption are relatively insensitive to temperature in the physiologic and surgical range. Conclusions Xenon anesthesia results in gas exchange conditions that favor bubble growth, which may worsen neurologic injury from gas embolism. The concentration gradients can be manipulated by discontinuation of xenon delivery to promote reabsorption of xenon-containing bubbles. Estimated growth and reabsorption rates at normothermia can be applied to temperature extremes of cardiopulmonary bypass.

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7

Holsträter, Thorsten Frederik, Michael Georgieff, Karl Josef Föhr, Werner Klingler, Miriam Elisabeth Uhl, Tobias Walker, Sarah Köster, Georg Grön, and Oliver Adolph. "Intranasal Application of Xenon Reduces Opioid Requirement and Postoperative Pain in Patients Undergoing Major Abdominal Surgery." Anesthesiology 115, no. 2 (August 1, 2011): 398–407. http://dx.doi.org/10.1097/aln.0b013e318225cee5.

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Background Both central sensitization after peripheral tissue injury and the development of opioid tolerance involve activation of N-methyl-D-aspartate (NMDA) receptors. At subanesthetic doses the NMDA receptor antagonist xenon suppresses pain-evoked sensitization of pain-processing areas in the central nervous system. Although numerous studies describe the effect of NMDA receptor antagonists on postoperative pain, clinical studies elucidating their intraoperative analgesic potency when applied in a low dosage are still largely missing. Methods To analyze the analgesic effect of low-dose xenon using new application methods, the authors tested nasally applied xenon as an add-on treatment for analgesia in 40 patients undergoing abdominal hysterectomy. Within a randomized double-blind placebo-controlled study design, intraoperative and postoperative requirement of opioids as well as postoperative subjective experiences of pain were measured as primary outcome variables. Results Intranasal application of xenon significantly reduced intraoperative opioid requirement (mean difference [MD] -2.0 μg/min; 95% CI [CI95]-0.53 to -3.51, Bonferroni correction adjusted P value [pcorr]= 0.028) without relevant side effects and significantly reduced postoperative pain (MD -1.34 points on an 11-point rating scale; CI95 -0.60 to -2.09, pcorr = 0.002). However, postoperative morphine consumption (MD -8.8 μg/min; CI95 1.2 to -18.8, pcorr = 0.24) was not significantly reduced in this study. Conclusions Low-dose xenon significantly reduces intraoperative analgesic use and postoperative pain perception. Because NMDA receptor antagonists suppress central sensitization, prevent the development of opioid tolerance, and reduce postoperative pain, the intraoperative usage of NMDA receptor antagonists such as xenon is suggested to improve effectiveness of pain management within a concept of multimodal analgesia.

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Ylihautala, Mika, Petri Ingman, Jukka Jokisaari, and Peter Diehl. "129Xe and 131Xe NMR of Xenon in Mesophases of Cetyltrimethylammonium Bromide in Formamide." Applied Spectroscopy 50, no. 11 (November 1996): 1435–38. http://dx.doi.org/10.1366/0003702963904791.

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For the first time, noble gas NMR has been applied to a study of a lyotropic liquid crystal. 129Xe and 131Xe NMR spectra of natural xenon gas dissolved in pure formamide and three cetyltrimethylammonium bromide (CTAB)/formamide (FA) mixtures were recorded over wide temperature ranges. The CTAB/FA system forms micelles at low concentrations of CTAB and mesophases at higher concentrations and elevated temperatures. The phase transitions are observed in the series of xenon spectra. In addition, the free xenon gas signal is seen in the spectra at low temperature, when the CTAB/FA system has a coexisting solid/liquid phase. The gas signal indicates that Xe is not soluble in the solid but accumulates in macroscopic bubbles. The intensity variation of the central peak of the 131Xe NMR spectra shows the presence of a static external electric field gradient (EFG). However, the spectral satellites are not observed and, therefore, the magnitude of the EFG cannot be determined. The obvious reason for the missing 131Xe satellites is the orientation distribution of the EFG tensor leading to broadening of the satellites.

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9

Zhu, WeiDong, and Prajwal Niraula. "The missing modes of self-organization in cathode boundary layer discharge in xenon." Plasma Sources Science and Technology 23, no. 5 (September 25, 2014): 054011. http://dx.doi.org/10.1088/0963-0252/23/5/054011.

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10

Lee, Kanani K. M., and Gerd Steinle-Neumann. "High-pressure alloying of iron and xenon: “Missing” Xe in the Earth's core?" Journal of Geophysical Research: Solid Earth 111, B2 (February 2006): n/a. http://dx.doi.org/10.1029/2005jb003781.

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11

Krzeminski, Jakub, Bartosz Blicharz, Andrzej Skalski, Grzegorz Wroblewski, Małgorzata Jakubowska, and Marcin Sloma. "Photonic curing of silver paths on 3D printed polymer substrate." Circuit World 45, no. 1 (February 4, 2019): 9–14. http://dx.doi.org/10.1108/cw-11-2018-0084.

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Purpose Despite almost limitless possibilities of rapid prototyping, the idea of 3D printed fully functional electronic device still has not been fulfilled – the missing point is a highly conductive material suitable for this technique. The purpose of this paper is to present the usage of the photonic curing process for sintering highly conductive paths printed on the polymer substrate. Design/methodology/approach This paper evaluates two photonic curing processes for the conductive network formulation during the additive manufacturing process. Along with the xenon flash sintering for aerosol jet-printed paths, this paper examines rapid infrared sintering for thick-film and direct write techniques. Findings This paper proves that the combination of fused deposition modeling, aerosol jet printing or paste deposition, along with photonic sintering, is suitable to obtain elements with low resistivity of 3,75·10−8 Ωm. Presented outcomes suggest the solution for fabrication of the structural electronics systems for daily-use applications. Originality/value The combination of fused deposition modelling (FDM) and aerosol jet printing or paste deposition used with photonic sintering process can fill the missing point for highly conductive materials for structural electronics.

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12

Tolstikhin, I. N., and R. K. O'Nions. "The Earth's missing xenon: A combination of early degassing and of rare gas loss from the atmosphere." Chemical Geology 115, no. 1-2 (July 1994): 1–6. http://dx.doi.org/10.1016/0009-2541(94)90142-2.

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13

Marti, Kurt, and K. J. Mathew. "Xenon in the Protoplanetary Disk (PPD), in Two Planets, and a Comet." Astrophysical Journal 940, no. 1 (November 1, 2022): 14. http://dx.doi.org/10.3847/1538-4357/ac9904.

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Abstract Isotopic anomalies in several elements, as recently observed in meteorites, are generally interpreted to indicate nonequilibrium environments in the protoplanetary disk (PPD). Here we study reported Xe isotopic compositions on planets Earth and Mars, in a comet, and in meteorites for precursor discrepancies. Abundance variations of inferred presolar nano-diamonds, the carrier phase of the Xe-HL component, appear to be the primary source of nonuniformity of Xe precursors in the PPD, together with mechanisms of mass-dependent fractionation. While planet Mars kept a record of initial solar Xe isotopic abundances, such a record is missing for planet Earth. Xe isotopic abundances in paleo-atmospheres of both planets represent secondary reservoirs that show mass-dependent fractionation effects, but the inferred compositions of their PPD precursors differ: Mars atmospheric precursor Xe had solar isotopic composition, while Earth’s Xe precursor is consistent with a PPD reservoir of low nano-diamond abundance. Strong mass-dependent fractionation effects are observed in Xe components of IAB irons and in Yamato carbonaceous (CY) chondrites, and show that fractionation mechanisms are not restricted to planetary atmospheres. These records show that Xe isotopes in solar system reservoirs are useful tracers of evolutionary processes and of nonequilibrated presolar components in the PPD.

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Péron, Sandrine, and Sujoy Mukhopadhyay. "Pre-subduction mantle noble gas elemental pattern reveals larger missing xenon in the deep interior compared to the atmosphere." Earth and Planetary Science Letters 593 (September 2022): 117655. http://dx.doi.org/10.1016/j.epsl.2022.117655.

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15

Meregaglia, Anselmo. "Latest results of the R2D2 project." Journal of Physics: Conference Series 2374, no. 1 (November 1, 2022): 012028. http://dx.doi.org/10.1088/1742-6596/2374/1/012028.

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The search for neutrinoless double beta decay (0𝜈𝜈β) could cast light on one critical piece missing in our knowledge i.e. the nature of the neutrino mass. Its observation is indeed the most sensitive experimental way to prove that neutrino is a Majorana particle. The observation of such a potentially rare process demands a detector with an excellent energy resolution, an extremely low radioactivity and a large mass of emitter isotope. Nowadays many techniques are pursued but none of them meets all the requirements at the same time. R2D2 is an R&D project aiming to prove that a spherical high pressure gas TPC filled with xenon could meet all the requirements and provide an ideal detector for the 0𝜈ββ decay search. An excellent energy resolution has been demonstrated in argon with a first prototype, meeting the expectations. Furthermore the energy resolution has been proved to be independent on the particle track’s length. In the presented talk the latest R2D2 results are discussed as well as the preliminary results on the scintillation light detection which could serve as trigger for a better position reconstruction. The project roadmap and future developments are also discussed.

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16

Ivanova, Maria V., Hélène P. A. Mercier та Gary J. Schrobilgen. "[XeOXeOXe]2+, the Missing Oxide of Xenon(II); Synthesis, Raman Spectrum, and X-ray Crystal Structure of [XeOXeOXe][μ-F(ReO2F3)2]2". Journal of the American Chemical Society 137, № 41 (7 жовтня 2015): 13398–413. http://dx.doi.org/10.1021/jacs.5b08765.

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Calvo, Eduardo M., Mario J. Pinheiro, and Paulo A. Sá. "Modeling of Electrohydrodynamic (EHD) Plasma Thrusters: Optimization of Physical and Geometrical Parameters." Applied Sciences 12, no. 3 (February 4, 2022): 1637. http://dx.doi.org/10.3390/app12031637.

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This work aims to optimize a previous self-consistent model of a single stage electrohydrodynamic (EHD) thruster for space applications. The investigated parameters were the thruster performance (propulsion force T, the thrust to power ratio T/P, the electric potential distribution, the spatial distribution for the electrons and ions, and the laminar flow velocity) under several conditions, such as the design features related to the cathode’s cylindrical geometry (height and radius) and some electric parameters such as the ballast resistor, and the applied potential voltage. In addition, we examined the influence of the secondary electron emission coefficient on the plasma propellant parameters. The anode to cathode potential voltage ranges between 0.9 and 40 kV, and the ballast resistance varies between 500 and 2500 M. Argon and xenon are the working gases. We assumed the gas temperature and pressure constant, 300 K and 1.3 kPa (10 Torr), respectively. The optimal matching for Xe brings off a thrust of 3.80 μN and an efficiency T/P = 434 mN/kW, while for Ar, T = 2.75 μN, and thruster to the power of 295 mN/kW. To our knowledge, the missing data in technical literature does not allow the verification and validation (V&V) of our numerical model.

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Ivanova, Maria V., Helene P. A. Mercier та Gary J. Schrobilgen. "ChemInform Abstract: [XeOXeOXe]2+, the Missing Oxide of Xenon(II); Synthesis, Raman Spectrum, and X-Ray Crystal Structure of [XeOXeOXe][μ-F(ReO2F3)2]2." ChemInform 47, № 5 (січень 2016): no. http://dx.doi.org/10.1002/chin.201605019.

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Mimura, Mitsuteru, Hiroki Kusano, Shingo Kobayashi, Mitsuhiro Miyajima, and Nobuyuki Hasebe. "Xenon Time Projection Chamber for Next-Generation Planetary Missions." Journal of the Physical Society of Japan 78, Suppl.A (January 2009): 157–60. http://dx.doi.org/10.1143/jpsjs.78sa.157.

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Meshik, Alex, Olga Pravdivtseva, and Donald Burnett. "Refined composition of Solar Wind xenon delivered by Genesis NASA mission: Comparison with xenon captured by extraterrestrial regolith soils." Geochimica et Cosmochimica Acta 276 (May 2020): 289–98. http://dx.doi.org/10.1016/j.gca.2020.03.001.

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Amer, Ashraf R., and Dorothy E. Oorschot. "Xenon Combined With Hypothermia in Perinatal Hypoxic-Ischemic Encephalopathy: A Noble Gas, a Noble Mission." Pediatric Neurology 84 (July 2018): 5–10. http://dx.doi.org/10.1016/j.pediatrneurol.2018.02.009.

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22

Vogel, Nadia, Veronika S. Heber, Heinrich Baur, Donald S. Burnett, and Rainer Wieler. "Argon, krypton, and xenon in the bulk solar wind as collected by the Genesis mission." Geochimica et Cosmochimica Acta 75, no. 11 (June 2011): 3057–71. http://dx.doi.org/10.1016/j.gca.2011.02.039.

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23

Crowther, S. A., and J. D. Gilmour. "Measuring the elemental abundance and isotopic signature of solar wind xenon collected by the Genesis mission." J. Anal. At. Spectrom. 27, no. 2 (2012): 256–69. http://dx.doi.org/10.1039/c1ja10163c.

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24

Messo, Elias, Carlo F. Grottoli, Giuseppe Perale, and Jan-Michaél Hirsch. "Custom-Made Horizontal and Vertical Maxillary Augmentation with Smartbone® On Demand™: A Seven-Year Follow-Up Case." Applied Sciences 10, no. 22 (November 13, 2020): 8039. http://dx.doi.org/10.3390/app10228039.

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The presence of non-sufficient bone height and width requires an increase in the amount of bone available to insert an implant. Different materials are described in the literature, and the “custom-made bone graft approach” is a modern option which currently requires a preoperative stage of studying the bone defect and designing the implant. SmartBone® (SB®) mimics the characteristics of healthy human bone. Thanks to the strong performance, high workability, resistance and shape retention of SB®, it is possible to obtain SmartBone® on DemandTM, a bone graft uniquely shaped exactly to patient specifications, produced by following the data precisely and contoured to the bone defect site. The aim of this study was to determine the success over 7 years following a customized SmartBone® on DemandTM, a xeno-hybrid bone graft and installation of implants in a maxillary horizontal and vertical atrophy. This case study presents the diagnosis for a 60-year-old male patient requesting the rehabilitation of his edentulous maxilla with dental implants. Preoperative evaluation included the study of photographs, a radiological examination and 3D reconstruction to assess the missing bone, implant size, positioning of implants and anatomical landmarks. Rehabilitation included the insertion of a custom-made xeno-hybrid bone block into the maxilla in order to restore the anatomy prior to the implants’ placement. The newly developed bone substitute SB® is a safe and effective material, and its custom-made variant SmartBone® on DemandTM has been shown to be a valid alternative to traditional autologous bone grafting techniques in terms of accuracy, absence of infection/rejection and overall clinical outcome.

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25

Santiago, Daniel. "A Partial Answer to the Question Posed by David A. Hughes, PhD, in the Article: “What is in the so-called COVID-19 ‘Vaccines’? Part 1: Evidence of a Global Crime Against Humanity”." International Journal of Vaccine Theory, Practice, and Research 2, no. 2 (September 7, 2022): 587–94. http://dx.doi.org/10.56098/ijvtpr.v2i2.56.

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In this comment, originally thought of as a “Letter to the Editor”, I want to address the opening question posed by David A. Hughes in the immediately preceding entry in this journal: “What is in the so-called COVID-19 ‘Vaccines’?” The views from under the microscope, ordinary light or electron scanning, all show undisclosed foreign objects that seem to activate themselves and aggregate into complexes that disrupt blood flow in all organ systems. With the spectral analysis using electron microscopy it is possible to determine the specific elements and relative quantities of the elements in those foreign entities. In this comment, I want to focus on the absence of certain elements that are universally present in the proteins of naturally occurring life forms from humans right down to bacteria and even the proteins formed from viruses. What is missing from the spectral analyses of the foreign elements in the main COVID-19 vaccines, Pfizer and Moderna for certain, and probably also missing from the other experimental products being widely distributed that are known to contain foreign aggregates of strange materials similar to those found in the Moderna and Pfizer injections, are the elements nitrogen and phosphorous. This is revealing because all natural DNA, RNA, and their protein products contain those missing elements. Nitrogen for protein synthesis and phosphorus for DNA, RNA, and energy transfer. Therefore, their absence from the foreign structures seen under many different microscopes in all of the COVID-19 so-called “vaccines” that have been examined, and also found in blood samples of persons injected with the Moderna and Pfizer concoctions, proves that these intentionally manufactured self-assembling components, built mainly from carbon-based materials used in computing and super-conductors, are connected with the avant-guard evolutionary theory and experimentation with what is known as XNA, Xeno (Greek for “foreign”), Nucleic Acid. Most of the relevant information is behind significant paywalls in esoteric journals specializing in this peculiar branch of highly theoretical and experimental chemistry. To leap to the bottom-line of my urgent comment on the Hughes’ paper, the edgy modified mRNA with N1-methylpseudouridine (Ψ) replacing the naturally occurring RNA nucleotide uridine (U) at least 728 times in each one of the 30 billion mRNA molecules in each of the Pfizer injections is an exmplary XNA. In this comment I want to explain why the inclusion of such an XNA may be the clue that leads to the unraveling of the already devastating and potentially exterminating impact of the ongoing COVID-19 experiment on the human race.

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Melchor, Lorenzo, Annamaria Brioli, Christopher P. Wardell, Alexander Murison, Nicola E. Potter, Martin F. Kaiser, Rosemary A. Fryer, et al. "Single-Cell Genetic Analysis Reveals The Genetic Composition Of Founder Clones, Phylogenetic Patterns Of Branching and Parallel Evolution, and Clonal Fluctuations Following Patient Treatment In Multiple Myeloma." Blood 122, no. 21 (November 15, 2013): 398. http://dx.doi.org/10.1182/blood.v122.21.398.398.

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Abstract Multiple Myeloma (MM) is a proliferation of aberrant plasma cells in the bone marrow. Ig translocations or hyperdiploidy are MM initiating events present in all clonal cells in contrast to other secondary lesions involved in progression (e.g. RASmutations), which may be subclonal. We and others have recently described the presence of different tumour clonal populations—a phenomenon called intra-tumour heterogeneity—in MM, yet the phylogenetic relationships of the tumour subclones remains to be fully elucidated. To describe the intra-tumour heterogeneity and tumour phylogenies in a series of t(11;14) MM patients characterised by KRAS/NRAS/BRAF mutations, we combined whole-exome sequencing and single-cell genetic analysis. A novel approach for single-cell multiplex-qPCR analysis using nano-fluidic arrays (Fluidigm) was followed in 100-250 single-cells per sample. The t(11;14) breakpoint was defined using Ig regions-targeted massively-parallel sequencing. Taqman assays specific for detection of the t(11;14) breakpoints and for mutations in selected genes were custom-made designed. Copy number assays for chromosomal regions of interest were also used. This strategy allowed us: first, to report the presence of the t(11;14), mutations and copy number aberrations (gains/losses) at the single-cell level; second, to define subclonal populations; and third, to delineate the most plausible sequence of events for each case. An additional series of 14 MM patients with paired-samples at presentation/relapse was included for the study of the effect of treatment in clonal architecture. Lastly, to analyse the engraftment-ability of subclonal populations, we injected 1x106 CD138+ cells from one of the patient-samples at diagnosis into the tibia of NOD/SCIDyc(null)-mice and compared the engrafted-myeloma with the paired presentation-relapse samples. We demonstrate that MM is comprised of 2-6 clones, related through a linear (3/7 cases) or a branching (4/7) phylogeny. The t(11;14) was seen in 91-100% of tumour cells, supporting its aetiological role as a MM initiating event. For the first time in MM, we describe a parallel evolutionary pattern in two samples that carried double hits in KRAS or KRAS/NRAS. These mutations were acquired separately in two divergent clonal lineages, which were derived from the same ancestor but evolved independently. We suggest that RAS is a true driver mutation in MM as such alterations seem to provide clonal advantages for myeloma subclones in the bone marrow environment. We also report the concomitant acquisition of RAS mutations and IRF4p.K123R mutation in 2% (9/453) screened MM patients. This finding suggests a collaborative effect provided by the mutations in both pathways to trigger myeloma development. We examine the ability of subclonal populations to survive patient treatment by the analysis of paired presentation-relapse samples. Not only did the intra-tumour heterogeneity shift in the transition to relapse meaning that subclonal populations fluctuated during treatment, but also new clones emerged from early and late subclones formerly described at diagnosis. To note, some of these new subclones acquired mutations in KRAS/BRAF during transition, likely leading to relapse. In parallel, we tested the ability to recapitulate the disease in NOD/SCIDyc(null)-mice. Engrafted-myelomas also had clonal fluctuations with 1/3 clones shown at patient-diagnosis neither found at relapse, nor in the engrafted-MM. This missing clone was similarly outcompeted by the other clones during patient treatment and xeno-transplantation. Altogether, these results suggest that subclonal populations have different abilities to survive treatment or xeno-transplantation and hence, to lead to relapse or reconstitution of myeloma by the generation of new clonal subpopulations. We confirm the existence of distinct MM subclones that are related through a linear or a branching phylogeny, with examples of parallel evolution for alteration of the RAS/MAPK pathway. Myeloma subclones are subject of a selection process involving clonal extinction and clonal tides, similar to the theory of Natural Selection by Charles Darwin. In conclusion, intra-tumour heterogeneity is an elementary foundation for Darwinian selection underlying both disease progression and the development of treatment resistance in MM. Disclosures: No relevant conflicts of interest to declare.

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Echchannaoui, Hakim, Jutta Petschenka, Edite Antunes, and Matthias Theobald. "Gene Therapy With a High-Affinity Single-Chain p53-Specific TCR Mediates Potent Anti-Tumor Response Without Inducing Gvhd In Vivo." Blood 122, no. 21 (November 15, 2013): 1657. http://dx.doi.org/10.1182/blood.v122.21.1657.1657.

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Abstract The adoptive transfer of tumor-reactive cells is a promising approach in the treatment of human malignancies, but the challenge of isolating T cells with high-avidity for tumor antigens in each patient has limited its widespread application. Using HLA-A2.1 transgenic mice, we have demonstrated the feasibility of T-cell receptor (TCR) gene transfer into T cells to circumvent self-tolerance to the widely expressed human p53(264-272) tumor-associated antigen and developed approaches to generate high-affinity CD8-independent TCR. However, a safety concern of TCR gene transfer is the risk of pairing between introduced and the naturally expressed endogenous TCR chains, resulting in the generation of self-reactive T cells (off-target autoimmunity). We first genetically modified p53TCR constructs to minimize mispairing and improve correct pairing of the introduced TCR. We and others have shown that, cysteine modifications are able to increase the expression of the introduced TCR but fail to prevent mispairing formation in mouse and human T cells. To further enhance preferential TCR pairing, cell surface expression and TCR function, we introduced additional cysteine residues into the TCR α and β chain constant domains along with codon-optimization of the TCR sequences and cloning of the TCR constructs into one single 2A-based retroviral vector. To overcome TCR mispairing formation, we designed a single chain (sc) TCR by connecting the variable TCRa domain to the TCRb chain via a short peptide linker co-expressed with a truncated constant TCR a domain. Beside off-target toxicity, adoptive transfer of high-avidity T cells may potentially cause severe on-target toxicity for normal cells expressing low level of antigens. In this respect, pre-clinical in vivo studies are still missing. Here, we evaluated the safety issues raised by the risk of p53TCR gene transfer-associated on/off-target toxicities in relevant mouse models of adoptive transfer. In vitro studies showed that, scTCR-modified CD4+ and CD8+ T cells displayed similar high-avidity compared to the full-length TCR, as determined by peptide titration in cytotoxicity assays and were able to mediate specific lysis of p53 mutant A2.1+ tumor cells. Though, genetic modifications preserved the antigen specificity of these TCRs, the full-length version of the TCR could not prevent mispairing-mediated lethal off-target autoimmunity in vivo. In sharp contrast, T cells engrafted with the modified scTCR did not induce graft-versus-host disease (GVHD) following adoptive transfer. We next assessed the potential of scTCR-modified T cells to cause on-target autoimmunity in vivo, using mice which express the human wild type p53 and A2.1Kb (Hupki-A2.1Kb). We found that lymphodepleting preconditioning regimens plus vaccination-induced expansion of transferred TCR-specific T cells did not result in a depletion of hematopoietic cells, as mice recovered normal white blood cell counts, including lymphocytes and monocytes and survived without any sign of toxicity. Importantly, our study demonstrated that high-avidity scTCR-engineered human T cells were able to eradicate established tumors and persist for more than 6 months after infusion without inducing xeno-GVHD in NodScid IL-2R gamma chain-null mice. Taken together, our study provided evidence that an optimized high-affinity scTCR-specific for the broadly expressed tumor-associated antigen p53(264-272) can eradicate p53+A2.1+ tumor cells in vivo without inducing off-target or self-directed toxicities in humanized mouse models of adoptive T-cell transfer. These data strongly support the improved safety and therapeutic efficacy of high-affinity scp53TCR for TCR-based immunotherapy of p53-associated malignancies. Disclosures: No relevant conflicts of interest to declare.

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Peng, Feng, Xianqi Song, Chang Liu, Quan Li, Maosheng Miao, Changfeng Chen, and Yanming Ma. "Xenon iron oxides predicted as potential Xe hosts in Earth’s lower mantle." Nature Communications 11, no. 1 (October 16, 2020). http://dx.doi.org/10.1038/s41467-020-19107-y.

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Abstract An enduring geological mystery concerns the missing xenon problem, referring to the abnormally low concentration of xenon compared to other noble gases in Earth’s atmosphere. Identifying mantle minerals that can capture and stabilize xenon has been a great challenge in materials physics and xenon chemistry. Here, using an advanced crystal structure search algorithm in conjunction with first-principles calculations we find reactions of xenon with recently discovered iron peroxide FeO2, forming robust xenon-iron oxides Xe2FeO2 and XeFe3O6 with significant Xe-O bonding in a wide range of pressure-temperature conditions corresponding to vast regions in Earth’s lower mantle. Calculated mass density and sound velocities validate Xe-Fe oxides as viable lower-mantle constituents. Meanwhile, Fe oxides do not react with Kr, Ar and Ne. It means that if Xe exists in the lower mantle at the same pressures as FeO2, xenon-iron oxides are predicted as potential Xe hosts in Earth’s lower mantle and could provide the repository for the atmosphere’s missing Xe. These findings establish robust materials basis, formation mechanism, and geological viability of these Xe-Fe oxides, which advance fundamental knowledge for understanding xenon chemistry and physics mechanisms for the possible deep-Earth Xe reservoir.

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29

"Earth's missing xenon could hide in iron's hot embrace." New Scientist 220, no. 2937 (October 2013): 16. http://dx.doi.org/10.1016/s0262-4079(13)62374-x.

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30

Murra, M., D. Schulte, C. Huhmann, and C. Weinheimer. "Design, construction and commissioning of a high-flow radon removal system for XENONnT." European Physical Journal C 82, no. 12 (December 7, 2022). http://dx.doi.org/10.1140/epjc/s10052-022-11001-9.

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AbstractA high-flow radon removal system based on cryogenic distillation was developed and constructed to reduce radon-induced backgrounds in liquid xenon detectors for rare event searches such as XENONnT. A continuous purification of the XENONnT liquid xenon inventory of 8.4 tonnes at process flows up to 71 kg/h (200 slpm) is required to achieve a radon reduction by a factor larger than two for radon sources inside the detector. To reach such high flows, the distillation column’s design features liquid xenon inlet and outlets along with novel custom-made bath-type heat exchangers with high liquefaction capabilities. The distillation process was designed using a modification of the McCabe–Thiele approach without a bottom product extraction. The thermodynamic concept is based on a Clausius–Rankine cooling cycle with phase-changing medium, in this case the xenon itself. To drastically reduce the external cooling power requirements, an energy efficient heat pump concept was developed applying a custom-made four cylinder magnetically-coupled piston pump as compressor. The distillation system was operated at thermodynamically stable conditions at a process flow of $$({91\pm 2})\,\mathrm{kg/h}$$ ( 91 ± 2 ) kg / h (($$258\pm 6$$ 258 ± 6 ) slpm), 30% over design. With this flow, a "Image missing" activity concentration $$<1\,\upmu $$ < 1 μ Bq/kg is expected inside the XENONnT detector given the measured radon source distribution.

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31

Sun, P. Z., M. Yagmurcukardes, R. Zhang, W. J. Kuang, M. Lozada-Hidalgo, B. L. Liu, H. M. Cheng, et al. "Exponentially selective molecular sieving through angstrom pores." Nature Communications 12, no. 1 (December 2021). http://dx.doi.org/10.1038/s41467-021-27347-9.

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AbstractTwo-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules’ kinetic diameter, and the effective diameter of the created pores is estimated as ∼2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance.

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Bottaro, Salvatore, Dario Buttazzo, Marco Costa, Roberto Franceschini, Paolo Panci, Diego Redigolo, and Ludovico Vittorio. "Closing the window on WIMP Dark Matter." European Physical Journal C 82, no. 1 (January 2022). http://dx.doi.org/10.1140/epjc/s10052-021-09917-9.

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AbstractWe study scenarios where Dark Matter is a weakly interacting particle (WIMP) embedded in an ElectroWeak multiplet. In particular, we consider real SU(2) representations with zero hypercharge, that automatically avoid direct detection constraints from tree-level Z-exchange. We compute for the first time all the calculable thermal masses for scalar and fermionic WIMPs, including Sommerfeld enhancement and bound states formation at leading order in gauge boson exchange and emission. WIMP masses of few hundred TeV are shown to be compatible both with s-wave unitarity of the annihilation cross-section, and perturbativity. We also provide theory uncertainties on the masses for all multiplets, which are shown to be significant for large SU(2) multiplets. We then outline a strategy to probe these scenarios at future experiments. Electroweak 3-plets and 5-plets have masses up to about 16 TeV and can efficiently be probed at a high energy muon collider. We study various experimental signatures, such as single and double gauge boson emission with missing energy, and disappearing tracks, and determine the collider energy and luminosity required to probe the thermal Dark Matter masses. Larger multiplets are out of reach of any realistic future collider, but can be tested in future $$\gamma $$ γ -ray telescopes and possibly in large-exposure liquid Xenon experiments.

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