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Combination of Cladding Processes with Subsequent Hot Forming as a New Approach for the Production of Hybrid Components
A new process chain for the manufacturing of load-adapted hybrid components is presented. The "Tailored
Formingâ process chain consists of a deposition welding process, hot forming, machining and an optional heat
treatment. This paper focuses on the combination of laser hot-wire cladding with subsequent hot forming to
produce hybrid components. The applicability is investigated for different material combinations and component
geometries, e.g. a shaft with a bearing seat or a bevel gear. Austenitic stainless steel AISI 316L and martensitic
valve steel AISI HNV3 are used as cladding materials, mild steel AISI 1022M and case hardening steel AISI 5120
are used as base materials. The resulting component properties after laser hot-wire cladding and hot forming such
as hardness, microstructure and residual stress state are presented. In the cladding and the heat-affected zone, the
hot forming process causes a transformation from a welding microstructure to a fine-grained forming
microstructure. Hot forming significantly affects the residual stress state in the cladding the resulting residual
stress state depends on the material combination.Mechanical Engineerin
Neuropsychiatric phenotype of post COVID-19 syndrome in non-hospitalized patients
The post COVID-19 syndrome (PCS) is an emerging phenomenon worldwide with enormous socioeconomic impact. While many patients describe neuropsychiatric deficits, the symptoms are yet to be assessed and defined systematically. In this prospective cohort study, we report on the results of a neuropsychiatric consultation implemented in May 2021. A cohort of 105 consecutive patients with merely mild acute course of disease was identified by its high symptom load 6 months post infection using a standardized neurocognitive and psychiatric-psychosomatic assessment. In this cohort, we found a strong correlation between higher scores in questionnaires for fatigue (MFI-20), somatization (PHQ15) and depression (PHQ9) and worse functional outcome as measured by the post COVID functional scale (PCFS). In contrast, neurocognitive scales correlated with age, but not with PCFS. Standard laboratory and cardiopulmonary biomarkers did not differ between the group of patients with predominant neuropsychiatric symptoms and a control group of neuropsychiatrically unaffected PCS patients. Our study delineates a phenotype of PCS dominated by symptoms of fatigue, somatisation and depression. The strong association of psychiatric and psychosomatic symptoms with the PCFS warrants a systematic evaluation of psychosocial side effects of the pandemic itself and psychiatric comorbidities on the long-term outcome of patients with SARS-CoV-2 infection
PADC nuclear track detector for ion spectroscopy in laser-plasma acceleration
[EN] The transparent polymer polyallyl-diglycol-carbonate (PADC), also known as CR-39, is widely used as detector for heavy charged particles at low fluence. It allows for detection of single protons and ions via formation of microscopic tracks after etching in NaOH or KOH solutions. PADC combines a high sensitivity and high specificity with inertness towards electromagnetic noise. Present fields of application include laser-ion acceleration, inertial confinement fusion, radiobiological studies with cell cultures, and dosimetry of nuclear fragments in particle therapy. These require precise knowledge of the energy-dependent response of PADC to different ion species. We present calibration data for a new type of detector material, Radosys RS39, to protons (0.2-3 MeV) and carbon ions (0.6-12 MeV). RS39 is less sensitive to protons than other types of PADC. Its response to carbon ions, however, is similar to other materials. Our data indicate that RS39 allows for measuring carbon ion energies up to 10 MeV only from the track diameters. In addition, it can be used for discrimination between protons and carbon ions in a single etching process.Project funded by CSIC, Grant No. 2018501082, and by the Spanish Ministerio de Ciencia, Innovacion y Universidades, project MdM-2016-0692-17-2 via a predoctoral grant of type Maria de Maeztu FPI. Nuclear track detector material and readout equipment have been provided by Radosys Ldt. (Budapest). The authors acknowledge the contributions and commitment of the CNA accelerator operators. MS would like to thank L. Ballesteros and J. Ortiz for their support with precision equipment.Seimetz, M.; Peñas, J.; Llerena, JJ.; Benlliure, J.; GarcĂa LĂłpez, J.; MillĂĄn-Callado, MA.; Benlloch Baviera, JM. (2020). PADC nuclear track detector for ion spectroscopy in laser-plasma acceleration. Physica Medica. 76:72-76. https://doi.org/10.1016/j.ejmp.2020.06.005S727676Kodaira, S., Kitamura, H., Kurano, M., Kawashima, H., & Benton, E. R. (2019). Contribution to dose in healthy tissue from secondary target fragments in therapeutic proton, He and C beams measured with CR-39 plastic nuclear track detectors. Scientific Reports, 9(1). doi:10.1038/s41598-019-39598-0Scampoli, P., Casale, M., Durante, M., Grossi, G., Pugliese, M., & Gialanella, G. (2001). Low-energy light ion irradiation beam-line for radiobiological studies. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 174(3), 337-343. doi:10.1016/s0168-583x(00)00622-4WADA, S., KOBAYASHI, Y., FUNAYAMA, T., NATSUHORI, M., ITO, N., & YAMAMOTO, K. (2002). Detection of DNA Damage in Individual Cells Induced by Heavy-ion Irradiation with an Non-denaturing Comet Assay. Journal of Radiation Research, 43(S), S153-S156. doi:10.1269/jrr.43.s153Gaillard, S., Pusset, D., de Toledo, S. M., Azzam, E. I., & Fromm, M. (2008). Distance distribution of bystander effects in alpha-particle irradiated cell populations using a CR-39-based culture dish. Radiation Measurements, 43, S34-S40. doi:10.1016/j.radmeas.2008.03.063Yogo, A., Maeda, T., Hori, T., Sakaki, H., Ogura, K., Nishiuchi, M., ⊠Kondo, K. (2011). Measurement of relative biological effectiveness of protons in human cancer cells using a laser-driven quasimonoenergetic proton beamline. Applied Physics Letters, 98(5), 053701. doi:10.1063/1.3551623SĂ©guin, F. H., Frenje, J. A., Li, C. K., Hicks, D. G., Kurebayashi, S., Rygg, J. R., ⊠Padalino, S. (2003). Spectrometry of charged particles from inertial-confinement-fusion plasmas. Review of Scientific Instruments, 74(2), 975-995. doi:10.1063/1.1518141Daido, H., Nishiuchi, M., & Pirozhkov, A. S. (2012). Review of laser-driven ion sources and their applications. Reports on Progress in Physics, 75(5), 056401. doi:10.1088/0034-4885/75/5/056401Sinenian, N., Rosenberg, M. J., Manuel, M., McDuffee, S. C., Casey, D. T., Zylstra, A. B., ⊠Petrasso, R. D. (2011). The response of CR-39 nuclear track detector to 1â9 MeV protons. Review of Scientific Instruments, 82(10), 103303. doi:10.1063/1.3653549Malinowska A, SzydĆowski A, JaskĂłĆa M, Korman A, Sartowska B, Kuehn T, Kuk M. Investigations of protons passing through the CR-39/PM-355 type of solid state nuclear track detectors, Rev Sci Instrum 84 (2013) 073511.Baccou, C., Yahia, V., Depierreux, S., Neuville, C., Goyon, C., Consoli, F., ⊠Labaune, C. (2015). CR-39 track detector calibration for H, He, and C ions from 0.1-0.5 MeV up to 5 MeV for laser-induced nuclear fusion product identification. Review of Scientific Instruments, 86(8), 083307. doi:10.1063/1.4927684Seimetz, M., Bellido, P., GarcĂa, P., Mur, P., Iborra, A., Soriano, A., ⊠Benlloch, J. M. (2018). Spectral characterization of laser-accelerated protons with CR-39 nuclear track detector. Review of Scientific Instruments, 89(2), 023302. doi:10.1063/1.5009587Xiaojiao, D., Xiaofei, L., Zhixin, T., Yongsheng, H., Shilun, G., Dawei, Y., & Naiyan, W. (2009). Calibration of CR-39 with monoenergetic protons. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 609(2-3), 190-193. doi:10.1016/j.nima.2009.08.061Kodaira, S., Morishige, K., Kawashima, H., Kitamura, H., Kurano, M., Hasebe, N., ⊠Ogura, K. (2016). A performance test of a new high-surface-quality and high-sensitivity CR-39 plastic nuclear track detector â TechnoTrak. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 383, 129-135. doi:10.1016/j.nimb.2016.07.002Ogura, K., Asano, M., Yasuda, N., & Yoshida, M. (2001). Properties of TNF-1 track etch detector. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 185(1-4), 222-227. doi:10.1016/s0168-583x(01)00816-3Malinowska, A., JaskĂłĆa, M., Korman, A., SzydĆowski, A., & Kuk, M. (2014). Characterization of solid state nuclear track detectors of the polyallyl-diglycol-carbonate (CR-39/PM-355) type for light charged particle spectroscopy. Review of Scientific Instruments, 85(12), 123505. doi:10.1063/1.4903755Bahrami, F., Mianji, F., Faghihi, R., Taheri, M., & Ansarinejad, A. (2016). Response of CR-39 to 0.9â2.5 MeV protons for KOH and NaOH etching solutions. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 813, 96-101. doi:10.1016/j.nima.2016.01.015Jeong, T. W., Singh, P. K., Scullion, C., Ahmed, H., Hadjisolomou, P., Jeon, C., ⊠Ter-Avetisyan, S. (2017). CR-39 track detector for multi-MeV ion spectroscopy. Scientific Reports, 7(1). doi:10.1038/s41598-017-02331-wKanasaki, M., Hattori, A., Sakaki, H., Fukuda, Y., Yogo, A., Jinno, S., ⊠Yamauchi, T. (2013). A high energy component of the intense laser-accelerated proton beams detected by stacked CR-39. Radiation Measurements, 50, 46-49. doi:10.1016/j.radmeas.2012.10.009Groza, A., Serbanescu, M., Butoi, B., Stancu, E., Straticiuc, M., Burducea, I., ⊠Ganciu, M. (2019). Advances in Spectral Distribution Assessment of Laser Accelerated Protons using Multilayer CR-39 Detectors. Applied Sciences, 9(10), 2052. doi:10.3390/app9102052Zhang, Y., Wang, H.-W., Ma, Y.-G., Liu, L.-X., Cao, X.-G., Fan, G.-T., ⊠Fang, D.-Q. (2019). Energy calibration of a CR-39 nuclear-track detector irradiated by charged particles. Nuclear Science and Techniques, 30(6). doi:10.1007/s41365-019-0619-xSeimetz, M., Bellido, P., Soriano, A., Garcia Lopez, J., Jimenez-Ramos, M. C., Fernandez, B., ⊠Benlloch, J. M. (2015). Calibration and Performance Tests of Detectors for Laser-Accelerated Protons. IEEE Transactions on Nuclear Science, 62(6), 3216-3224. doi:10.1109/tns.2015.2480682Rana, M. A., & Qureshi, I. . (2002). Studies of CR-39 etch rates. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 198(3-4), 129-134. doi:10.1016/s0168-583x(02)01526-4Hermsdorf, D., Hunger, M., Starke, S., & Weickert, F. (2007). Measurement of bulk etch rates for poly-allyl-diglycol carbonate (PADC) and cellulose nitrate in a broad range of concentration and temperature of NaOH etching solution. Radiation Measurements, 42(1), 1-7. doi:10.1016/j.radmeas.2006.06.009Azooz, A. A., & Al-Jubbori, M. A. (2013). Interrelated temperature dependence of bulk etch rate and track length saturation time in CR-39 detector. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 316, 171-175. doi:10.1016/j.nimb.2013.09.001JadrnĂÄkovĂĄ I, SpurnĂœ F. To the spectrometry of linear energy transfer in charged particle beams by means of track-etch detectors, Radiat Measure 43(2008): S191âS194, proceedings of the 23rd International Conference on Nuclear Tracks in Solids. doi: 10.1016/j.radmeas.2008.04.010.Sadowski, M., Al-Mashhadani, E. M., SzydĆowski, A., Czyzewski, T., GĆowacka, L., JaskĂłĆa, M., ⊠WieluĆski, M. (1995). Comparison of responses of CR-39 and PM-355 track detectors to fast protons, deuterons and 4He ions within energy range 0.2â4.5 MeV. Radiation Measurements, 25(1-4), 175-176. doi:10.1016/1350-4487(95)00066-nSadowski, M., Szydlowski, A., Jaskola, M., Czyzewski, T., & Kobzev, A. P. (1997). Comparison of responses of CR-39, PM-355, and CN track detectors to energetic hydrogen-, helium-, nitrogen-, and oxygen-ions. Radiation Measurements, 28(1-6), 207-210. doi:10.1016/s1350-4487(97)00069-3Henig, A., Steinke, S., SchnĂŒrer, M., Sokollik, T., Hörlein, R., Kiefer, D., ⊠Habs, D. (2009). Radiation-Pressure Acceleration of Ion Beams Driven by Circularly Polarized Laser Pulses. Physical Review Letters, 103(24). doi:10.1103/physrevlett.103.245003Kar, S., Kakolee, K. F., Qiao, B., Macchi, A., Cerchez, M., Doria, D., ⊠Borghesi, M. (2012). Ion Acceleration in Multispecies Targets Driven by Intense Laser Radiation Pressure. Physical Review Letters, 109(18). doi:10.1103/physrevlett.109.185006Palaniyappan, S., Huang, C., Gautier, D. C., Hamilton, C. E., Santiago, M. A., Kreuzer, C., ⊠FernĂĄndez, J. C. (2015). Efficient quasi-monoenergetic ion beams from laser-driven relativistic plasmas. Nature Communications, 6(1). doi:10.1038/ncomms10170McGuffey, C., Raymond, A., Batson, T., Hua, R., Petrov, G. M., Kim, J., ⊠Beg, F. N. (2016). Acceleration of high charge-state target ions in high-intensity laser interactions with sub-micron targets. New Journal of Physics, 18(11), 113032. doi:10.1088/1367-2630/18/11/113032Ma, W. J., Kim, I. J., Yu, J. Q., Choi, I. W., Singh, P. K., Lee, H. W., ⊠Nam, C. H. (2019). Laser Acceleration of Highly Energetic Carbon Ions Using a Double-Layer Target Composed of Slightly Underdense Plasma and Ultrathin Foil. Physical Review Letters, 122(1). doi:10.1103/physrevlett.122.014803Hegelich, M., Karsch, S., Pretzler, G., Habs, D., Witte, K., Guenther, W., ⊠Roth, M. (2002). MeV Ion Jets from Short-Pulse-Laser Interaction with Thin Foils. Physical Review Letters, 89(8). doi:10.1103/physrevlett.89.085002Henig, A., Kiefer, D., Markey, K., Gautier, D. C., Flippo, K. A., Letzring, S., ⊠Hegelich, B. M. (2009). Enhanced Laser-Driven Ion Acceleration in the Relativistic Transparency Regime. Physical Review Letters, 103(4). doi:10.1103/physrevlett.103.045002Carroll, D. C., Tresca, O., Prasad, R., Romagnani, L., Foster, P. S., Gallegos, P., ⊠McKenna, P. (2010). Carbon ion acceleration from thin foil targets irradiated by ultrahigh-contrast, ultraintense laser pulses. New Journal of Physics, 12(4), 045020. doi:10.1088/1367-2630/12/4/045020Jung, D., Yin, L., Albright, B. J., Gautier, D. C., Letzring, S., Dromey, B., ⊠Hegelich, B. M. (2013). Efficient carbon ion beam generation from laser-driven volume acceleration. New Journal of Physics, 15(2), 023007. doi:10.1088/1367-2630/15/2/023007Dollar, F., Zulick, C., Matsuoka, T., McGuffey, C., Bulanov, S. S., Chvykov, V., ⊠Krushelnick, K. (2013). High contrast ion acceleration at intensities exceeding 1021âWcmâ2. Physics of Plasmas, 20(5), 056703. doi:10.1063/1.4803082Kohno, R., Yasuda, N., Takeshi, H., Kase, Y., Ochiai, K., Komori, M., ⊠Kanai, T. (2005). Measurements of Dose-Averaged Linear Energy Transfer Distributions in Water Using CR-39 Plastic Nuclear Track Detector for Therapeutic Carbon Ion Beams. 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Structural and functional evolution of the P2Y12-like receptor group
Metabotropic pyrimidine and purine nucleotide receptors (P2Y receptors) belong to the superfamily of G protein-coupled receptors (GPCR). They are distinguishable from adenosine receptors (P1) as they bind adenine and/or uracil nucleotide triphosphates or diphosphates depending on the subtype. Over the past decade, P2Y receptors have been cloned from a variety of tissues and species, and as many as eight functional subtypes have been characterized. Most recently, several members of the P2Y12-like receptor group, which includes the clopidogrel-sensitive ADP receptor P2Y12, have been deorphanized. The P2Y12-like receptor group comprises several structurally related GPCR which, however, display heterogeneous agonist specificity including nucleotides, their derivatives, and lipids. Besides the established function of P2Y12 in platelet activation, expression in macrophages, neuronal and glial cells as well as recent results from functional studies implicate that several members of this group may have specific functions in neurotransmission, inflammation, chemotaxis, and response to tissue injury. This review focuses specifically on the structure-function relation and shortly summarizes some aspects of the physiological relevance of P2Y12-like receptor members
Involvement of the V2 Vasopressin Receptor in Adaptation to Limited Water Supply
Mammals adapted to a great variety of habitats with different accessibility to water. In addition to changes in kidney morphology, e.g. the length of the loops of Henle, several hormone systems are involved in adaptation to limited water supply, among them the renal-neurohypophysial vasopressin/vasopressin receptor system. Comparison of over 80 mammalian V2 vasopressin receptor (V2R) orthologs revealed high structural and functional conservation of this key component involved in renal water reabsorption. Although many mammalian species have unlimited access to water there is no evidence for complete loss of V2R function indicating an essential role of V2R activity for survival even of those species. In contrast, several marsupial V2R orthologs show a significant increase in basal receptor activity. An increased vasopressin-independent V2R activity can be interpreted as a shift in the set point of the renal-neurohypophysial hormone circuit to realize sufficient water reabsorption already at low hormone levels. As found in other desert mammals arid-adapted marsupials show high urine osmolalities. The gain of basal V2R function in several marsupials may contribute to the increased urine concentration abilities and, therefore, provide an advantage to maintain water and electrolyte homeostasis under limited water supply conditions
Flow cytometry enables dynamic tracking of algal stress response: A case study using carotenogenesis in Dunaliella salina
Effects of diode laser superposition on pulsed laser welding of aluminum
Pulsed laser welding of thin aluminum sheets is common for housing, where welding defects are detrimental especially in terms of hermetic packaging as well as electromagnetic compatibility. This paper shows investigations on laser welding of aluminum by superposition of a pulsed Nd:YAG laser with a diode laser in order to improve the weldability of aluminum. This configuration allows to enhance the absorption of the Nd:YAG welding laser due to preheating by the diode laser. Furthermore the effects of temporal pulse shaping have been studied experimentally. Deeper penetrations as well as an increased weld quality in terms of cracking were observed in welds manufactured with diode laser superposition. Besides this the modification of the thermal cycle by the combination of the two laser beams promotes advantageous solidification conditions and therefore hot cracks were efficiently reduced or avoided. Additionally solidification conditions can be actively influenced. The results show a decreasing number of defects and additionally an increase of the welding quality
Combined electrochemical and microscopic study of porous enzymatic electrodes with direct electron transfer mechanism
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