Cr Lines Research Articles

Intrinsic line profiles for X-ray fluorescent lines in SKIRT

X-ray microcalorimeter instruments are expected to spectrally resolve the intrinsic line shapes of the strongest fluorescent lines. X-ray models should therefore incorporate these intrinsic line profiles to obtain meaningful constraints from observational data. We included the intrinsic line profiles of the strongest fluorescent lines in the X-ray radiative transfer code SKIRT to model the cold-gas structure and kinematics based on high-resolution line observations from XRISM/Resolve and Athena /X-IFU. The intrinsic line profiles of the $ K and $ K lines of Cr, Mn, Fe, Co, Ni, and Cu were implemented based on a multi-Lorentzian parameterisation. Line energies are sampled from these Lorentzian components during the radiative transfer routine. In the optically thin regime, the SKIRT results match the intrinsic line profiles as measured in the laboratory. With a more complex 3D model that also includes kinematics, we find that the intrinsic line profiles are broadened and shifted to an extent that will be detectable with XRISM/Resolve; this model also demonstrates the importance of the intrinsic line shapes for constraining kinematics. We find that observed line profiles directly trace the cold-gas kinematics, without any additional radiative transfer effects. With the advent of the first XRISM/Resolve data, this update to the X-ray radiative transfer framework of SKIRT is timely and provides a unique tool for constraining the velocity structure of cold gas from X-ray microcalorimeter spectra.

Effect of single and double pulse laser-induced breakdown spectroscopy towards steel alloy in different gaseous media

In recent years, laser-induced breakdown spectroscopy (LIBS) technique showed its promising for material analysis, quality control, forensic science, and environmental safety monitoring. Besides, due to its rapid measurement capability and minimal sample-preparation requirements, it is a widely recognized elemental analysis approach used in a variety of study domains. The current work compares spatially resolved single (SP) and double pulse (DP), especially orthogonal DP, setups for LIBS to examine and enhance the limit of detection (LOD) in duplex stainless steels alloy. Using the Boltzmann plot method and the Stark broadening mechanism, the electron temperature and density of local arc plasma are highlighted due to single pulse and orthogonal pre-pulse double pulse configurations. With delay time, the circumstances of arc plasma's local thermodynamic equilibrium (LTE) of emission spectral lines are investigated. The experimental results show that there are significant increases in the spectral intensities of the Fe lines in double pulse LIBS under Ar-gas compared to those under He-gas. Internal standardization was used to create calibration curves for the spectral lines of Cr, Cu, and Mn in the alloy sample for the both studied media. It demonstrated that argon outperforms helium in determining the elemental composition of steel alloys. Furthermore, LOD for SP-LIBS and DP-LIBS in both media were calculated, which showed a higher detection LOD for DP-LIBS in the presence of Ar-gas compared to that in He-gas.

Abundances of Iron-peak Elements in the B8 Mn Star HD 110073

The synthesis of spectral intervals in the optical range allows the determination of LTE abundances of several iron-peak elements for the chemically peculiar B8 Mn star HD 110073. Titanium, chromium and manganese are found to be overabundant by factors of 19, 4 and 250 times their respective solar abundances. Iron and nickel are deficient by factors of 0.25 and 0.10. Weak lines of Cr ii formed deep in the atmosphere yield lower chromium abundances than strong lines do by a factor of 2. This supports that chromium is probably stratified vertically in the atmosphere of HD 110073. Several weak flat-bottomed lines which could be caused by vertical stratification of the abundances are present throughout the spectra. The new abundance determinations differ from previous determinations partly because the atomic data have changed. A non-uniform distribution of the elements over the surface of HD 110073 could also account for variation of the lines with time.

Monitoring the degree of dilution during directed energy deposition of aluminum bronze and H13 tool steel using optical emission spectroscopy

Controlling heat transfer in casting tools is a key quality aspect. It can be improved by selectively applying volumetric aluminum bronze (CuAl9.5Fe1.2) sections in the core of the tools and subsequently depositing these cores with hard-facing H13 tool steel. Directed energy deposition (DED) can be used for both additive manufacturing of aluminum bronze and hard-facing by depositing the filler material onto a substrate surface or previously manufactured bodies. A sufficient metallurgical bonding of the deposited filler material and the underlying layer must be ensured. Hence, the dilution is a key factor for quality assurance. However, high dilution of the underlying layer and the filler material negatively affects the desired properties and must be monitored. Optical emission spectroscopy of the DED process emissions is investigated by comparing the emission lines of the individual elements comprising the base and the filler materials. Multiple single tracks using aluminum bronze as the filler material are laser-cladded with varying power, onto the two different types of substrates, i.e., mild steel S355 (1.0570) and hot working tool steel H11 (1.2343). Additionally, single tracks of H13 (1.2344) are deposited with varying laser powers onto an additively manufactured core of aluminum bronze. Both resulting in deposition tracks with varying dilution values. Multiple emission lines of Cr, Fe, Cu, Al, and Mn are detected and measured (line intensity). Line intensity ratios using the element emission lines are calculated and correlated with the respective metallographic results of the deposition tracks (dilution and chemical composition). Deposition tracks with a higher dilution (CuAl9.5Fe1.2 onto S355/H11 as well as H13 onto CuAl9.5Fe1.2) showed an increased line intensity ratio of the underlying material to the filler material. Moreover, this technology was transferred in a multilayer industrial application.

Abstract 1100: miR205 mediates acquired resistance to ALK inhibition via targeting Mig6 expression and enhancing EGFR signaling

Abstract Complete responses to ALK tyrosine kinase inhibitors (TKIs) are rare and resistance eventually develops in ALK fusion-positive non-small cell lung cancer patients. To overcome resistance and improve therapeutic outcomes, it is crucial to understand the molecular mechanisms contributing to resistance. Our lab has previously shown EGFR signaling mediates adaptive resistance to ALK inhibitors. We demonstrated that RNA and protein levels of Mig6, an endogenous protein inhibitor of EGFR, were suppressed rapidly following ALK inhibition, thus unlocking EGFR from inhibition to support cell survival. In this study, we asked whether EGFR signaling activation and Mig6 suppression persist once acquired resistance is established. An EML4-ALK cell line, H3122, was continuously exposed to a fixed dose of the ALK inhibitor crizotinib to generate three resistant lines (H3122-CR1, -2, and -3). All H3122-CR lines lacked ALK kinase mutations and were also cross-resistant to other ALK TKIs including ceritinib and alectinib. We found phosphorylation and total EGFR were upregulated while Mig6 protein was attenuated across all resistant lines compared to their parental counterpart. Afatinib, a pan-ERBB family inhibitor, or Mig6 overexpression, was able to re-sensitize those resistant cells to ALK inhibition. Interestingly, we did not find Mig6 overexpression altered phosphorylation of EGFR. Previously reported data suggest that Mig6 competes with Shc1, a critical signaling adapter shared by ALK and EGFR, for the same substrate-binding cleft on EGFR. We then hypothesized Mig6 could block EGFR-Shc1 binding and downstream signaling transduction without directly impacting EGFR phosphorylation. Indeed, the co-immunoprecipitation assay showed Mig6 knockdown in H3122 cells enhanced Shc1 binding to EGFR without altering phosphorylation of EGFR itself, suggesting a novel mechanism in regulating EGFR signaling by impairing the signaling adapter binding. We then investigated the mechanism responsible for Mig6 protein attenuation in resistant lines. By examining the RNA-seq data for all the CR lines compared to the parental H3122, we found MIR205HG was substantially upregulated in resistant cells. MIR205HG is the host gene for miR-205, which was known to target ERRFI1 gene that encodes Mig6. Stem-loop RT-qPCR confirmed that miR-205 was increased ~5 fold in all CR lines. Overexpressing miR-205 in H3122 cells could downregulate Mig6 expression in a dose-dependent manner. Herein we presented a novel resistance mechanism to ALK inhibition by which miR205 upregulation attenuates Mig6 expression, releasing EGFR-Shc1 signaling transduction from inhibition to support cell survival. This study also provides additional support for targeting EGFR signaling to overcome ALK TKI resistance to improve patient survival. Citation Format: Nan Chen, Robert C. Doebele. miR205 mediates acquired resistance to ALK inhibition via targeting Mig6 expression and enhancing EGFR signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1100.

Graphene thin film microextraction and nanoparticle enhancement for fast LIBS metal trace analysis in liquids

Several strategies have been effectively tested in the past to improve the Laser Induced Breakdown Spectroscopy (LIBS) signal for the analysis of liquid samples, involving peculiar experimental configurations, such as Double Pulse LIBS (DP-LIBS). Recently, sample treatment has proven to be a viable and simple way to enhance the performances of LIBS towards the analysis of solutions. Among the various strategies, the most promising and versatile appears to be Thin Film Microextraction (TFME) using carbon-based adsorbents.Another sample pre-treatment procedure, Nanoparticle-Enhanced LIBS (NELIBS), has gained significant interest due to its relative simplicity and effectiveness. This methodology uses a deposition of silver nanoparticles (AgNPs) on the sample to greatly increase the emission of the LIBS plasma.In this work, we investigate for the first time the possibility of combining TFME and NELIBS. We developed TFME supports by depositing an aqueous graphene nano-sheets (aq-GRA) prepared by Pulsed Laser Ablation in Liquid (PLAL) on a glass substrate. The preparation of the supports was optimized with regards to the substrate nature, deposition method, sorbent volume and drying method. Then, the TFME supports were tested for the extraction of Chromium from aqueous solution at different extraction times and analyte concentration. Subsequently, the TFME supports were treated with a deposition of silver nanoparticles (AgNP) to test the feasibility of the NELIBS approach.We observed an enhancement in the emission lines of Cr when the AgNPs were applied, as well as a lower estimated LOD value when compared to plain graphene TFME supports.

The Line Variability of 78 Vir (A2p SrCrEu) in the Mid-ultraviolet

Abstract Line variations are studied in the mid-ultraviolet spectra of 78 Vir collected with IUE between phases of far-UV (FUV) maximum and FUV minimum. The mid-UV spectrum of 78 Vir is populated with low-lying transitions of iron-peak elements. The lines of Cr ii and Ca ii are found to be stronger at phase of FUV minimum, while the lines of Ni ii probably vary in anti phase with those of chromium and calcium. Those of Fe ii and Mn ii do not show convincing variations between the two phases. The analysis of these mid-ultraviolet spectra suggests that iron and manganese are uniformly distributed over the surface of 78 Vir, while chromium, calcium and nickel are not but more ultraviolet lines should be studied to confirm this.

Development of a methodology for the analysis of a fuel composition based on lithium and beryllium fluorides by atomic emission arc spectrometry

An atomic emission technique for the analysis of a fuel salt containing uranium and a coolant based on lithium and beryllium fluorides has been developed and tested. When developing the technique, the conditions accepted at Rosatom enterprises for the analysis of beryllium oxide and lithium carbonate were taken into account. The complexity of the structure of the arc spectrum of the matrix is noted. X-ray phase analysis of the sample residues in the electrodes revealed that the source of molecular bands in the spectra is lithium fluoroberillate. The analytical lines of Al, B, Ca, Cd, Cr, Cu, Fe, Mg, Ni, Pb, Si and Zn, free from overlap with the lines of the molecular spectrum and uranium were selected. A method of extreme experiment design is used to select optimal conditions for the arc excitation of the sample: the type and strength of the discharge current (alternating current 12 A), exposure time (20 sec), the shape of the electrode («glass») and the mass of the material (30 mg). Recommendations are given and implemented for the preparing samples for calibration using pure lithium fluoroberillate as a matrix material when introducing controlled elements in the form of certified reference materials of graphite (graphite collector of trace impurities). Calibration graphs in logarithmic coordinates are linear with angular coefficients close to unity. The metrological characteristics of the technique are evaluated in analysis of real samples: the repeatability, intermediate precision of the results and the limits of the element detection.

ГЕНОТИПИРОВАНИЕ УСТОЙЧИВОСТИ К КИЛЕ И ОЦЕНКА КОМБИНАЦИОННОЙ СПОСОБНОСТИ КАПУСТЫ ПЕКИНСКОЙ

Chinese cabbage is a multivitamin vegetable crop and it is in constant demand due to its taste and dietary qualities, as well as the ability to harvest this crop twice a year due to the short growing season. There are less than 70 cultivars and hybrids in the State Register of Russia, many of them are susceptible to clubroot caused by soil pathogen P.brassicae Wor. In Russia, consumer demand needs to be met with new competitive hybrids that are resistant to major diseases such as clubroot. The aim of the study to evaluate the collection of inbred Chinese cabbage lines with clubroot resistance and to select promising hybrid combinations for further creation of F1 hybrids of the crop. Field trials were carried out in the summer-autumn period of the year 2021. Twenty five Chinese cabbage inbred lines (B.rapa ssp. pekinensis) and 154 hybrid combinations from crossing these lines were used as plant material. To achieve the goal, the following methods were applied: evaluation of combining ability (GCA and SCA) in the system of crossings of two groups of genotypes; clubroot disease test; molecular genotyping using molecular markers of clubroot resistance genes. As a result of a Chinese cabbage hybrids field trials, 14 were identified that exceed the standards in terms of “mass of head” by at least 20%. Three CR inbred lines K7, K19 and P1d4 with high values of GCA were identified, which are recommended for development of a new hybrid combinations. Based on the data of molecular genotyping of the clubroot resistance genes CRa, CRb, and CRA05 and the disease resistance of Chinese cabbage lines, the genetic collection of lines was differentiated by clubroot resistance genes. This will make it possible to use them as resistance donors when pyramiding resistance genes.

Échelle spectroscopy of the chemically peculiar star θ1 Ori F

ABSTRACT We analyse Échelle spectra of θ1 Ori F obtained by us on six nights unevenly distributed along 6 yr; we identify several hundred spectral lines and measure, for the first time, the star’s heliocentric radial velocity. We also collect and discuss previously published photometry of θ1 Ori F. We find that θ1 Ori F is a chemically peculiar (CP) star with overabundant silicon and phosphorus, and possibly other elements as well. From the singly ionized Fe, Cr and Ti lines we estimate its spectral type to be between B7 and B8. The radial velocity of θ1 Ori F is possibly marginally variable, with an average of 24 ± 4.2 km s−1 (standard deviation), in good agreement with the mean radial velocity of the Orion Nebula Cluster members, and about 5 km s−1 smaller than the average of the other Trapezium components. We cast doubt on the coeval nature of this star relative to the other Trapezium components, and present arguments that almost certainly exclude its membership to the Orion Trapezium. θ1 Ori F turns out to be enigmatic in several respects, and is probably an important link for understanding the evolutionary stage at which the CP phenomenon sets on.

Abstract 2986: Conditional reprogramming of primary head and neck tumor cells to establish consistent and diverse cell line models

Abstract Introduction Head and neck squamous cell carcinoma (HNSCC) most commonly arise in the oral cavity, pharynx, and larynx and exhibit diverse molecular characteristics and clinical behavior across sites. Current models of HNSCC largely rely on immortalized cell lines, which suffer from selection bias and clonality. Primary cell cultures, on the other hand, are difficult to maintain and are limited by their finite ability to proliferate. Here, we describe the establishment of a robust HNSCC cell line bank using a “conditional reprogramming” (CR) method which relies on treatment with a rho kinase inhibitor (Y-27632) and co-culture with irradiated fibroblast (J2 strain) feeder cells to support indefinite tumor cell survival. Methods HNSCC tumors were acquired on an IRB-approved prospective tissue banking protocol. Tumor tissue and blood were collected from each patient, and tumor cells were digested and cultured using previously described CR methods. DNA was collected from tumor tissue and CR cultures and short tandem repeat (STR) profiling was used to validate culture against patient tumor tissue. To verify that the cultures were of squamous origin, western blot analysis was used to detect cytokeratin 5, cytokeratin 6 and p63. Tumor cell phenotype and growth characteristics were examined with light microscopy. HPV testing was carried out on DNA from CR cultures and matched tumor samples using PCR and specific genotyping by oligonucleotide hybridization. HPV testing was correlated with clinical p16 testing results. Whole exome sequencing was carried out on a subset of blood/tumor/CR culture samples. Results Eighteen CR lines were successfully cultured and validated with STR genotyping from 25 sequentially procured tumors. 10/18 were derived from oral cavity squamous cell cancers (SCCs), 5/18 were derived from oropharyngeal SCCs, and 3/18 were derived from laryngeal SCCs. 18/18 lines were found to express p63 and either cytokeratin 5 or 6, verifying these cultures contained tumor cells of squamous origin. 4/5 tumors from oropharyngeal SCCs were p16-positive on clinical testing and considered HPV-mediated. These 4 tumors all tested positive for HPV DNA in both tumor samples and CR cultures. Preliminary comparison of exome sequencing results between CR cultures and primary tumors suggests that overall mutational profiles are preserved through the tumor “conditional programming” process. Tumor heterogeneity between original tumor and CR culture is being actively compared in ongoing analyses. Conclusion We have consistently generated primary tumor CR cultures from patients with HNSCC arising in three major anatomical subsites of HNSCC disease, including HPV-mediated tumors. CR methods can be readily applied to all HNSCC tumors regardless of disease site and molecular background, providing a translational research model that can capture the molecular and phenotypic breadth of HNSCC disease. Citation Format: Daniel Li, Carlos Thomas, Nitisha Shrivastava, Nicholas Gadsden, Nicole Kawachi, Bradley A. Schiff, Richard V. Smith, Nicolas F. Schlecht, Michael B. Prystowsky, Gregory Rosenblatt, Stelby Augustine, Chandan Guha, Evripidis Gavathiotis, Robert D. Burk, Vikas Mehta, Thomas J. Ow. Conditional reprogramming of primary head and neck tumor cells to establish consistent and diverse cell line models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2986.

Optimization of the parameters of a laser induced breakdown spectrometer (LIBS) using probabilistic-deterministic design of experiment

A method for optimizing the settings of a LIBS device aimed at achieving the maximum intensity of analytical lines of the analyte of constant composition is considered using probabilistic-deterministic design of experiments (PDDE). A mixture of Cr, Mn, Fe, Co, and Ni oxides homogenized and diluted by fusion with a lead-phosphate mixture is used as an analyte. It is shown that data of mathematical processing of 25 spectra by the PDDE method can be used to develop mathematical models which relate the line intensity with the energy of the laser pumping lamp, the lag time of the first and second Q-switches, the time delay of the exposure onset, and the total exposure time. The use of the geometric mean and mathematical model in the form of the product of the partial dependences leads to a good correlation between the calculated and experimental values of the intensity for all the considered spectral lines. The simulation results presented for 16 analytical lines of Cr, Mn, Co, and Ni illustrate the applicability of the method under consideration. The experimentally achieved maximum intensities of analytical lines in the matrix of lead-phosphate glass differ from those calculated using the obtained models by 7 – 12 %. There is a linear correlation between the experimental and calculated values of the intensity at R2 = 0.99 and an inclination angle close to 45°. The spectra recorded during the experiment can be used for optimization of other parameters, e.g., the signal-to-noise ratio. The simplicity of calculations and relatively small number of tests in the optimization experiment make the PDDE a promising method for optimizing the LIBS parameters.

Rapid Elemental Determination And Discrimination Of Coins Using Laser-Induced Breakdown Spectroscopy

Damaged coins can be identified effectively via spectral analysis based on LIBS, which is of great significance for coin recycling. This paper takes the Renminbi (RMB), the Chinese currency, as the example, including the denominations of YI FEN, ER FEN, WU FEN, YI JIAO, WU JIAO and YI YUAN. Some characteristic lines of Mg, Al, Fe, Cr, Cu, Sn, Ni, Na and Ca were observed in the spectra, as well as the molecular bands of AlO. Principal component analysis (PCA) was used to reduce the dimension of the spectra of the different RMB coins. The samples after dimension reduction are classified by k-Nearest Neighbors (KNN), and 4 categories were obtained with a classification accuracy of 100%. Further, new spectra of different denomination RMB coins were added to the original data for the same analysis. The results are in good agreement which shows the potential of the combination of LIBS, PCA and KNN for the analysis and identification of different coins.

Insight into the origin of carbon matrix effects on the emission signal of atomic lines in inductively coupled plasma optical emission spectrometry

In inductively coupled plasma optical emission spectrometry (ICP-OES), the presence of carbon in the matrix strongly affects (positively and negatively) the emission signal of atomic lines. However, the emission signal of ionic lines is mostly unaffected by this concomitant. The goal of this work is to gain insight into the origin of carbon matrix effects on the signal of atomic lines in ICP-OES. To this end, the emission signal of a total of 3608 lines (i.e., 1755 atomic and 1853 ionic lines) of 62 elements (Ag, Al, As, Au, B, Ba, Be, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hg, Ho, I, In, Ir, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, P, Pb, Pd, Pr, Pt, Re, Rh, S, Sb, Sc, Se, Sm, Sn, Sr, Tb, Te, Th, Ti, Tm, U, V, Y, Yb, Zn and Zr) were registered for carbon containing solutions (20 g L−1) prepared from glycerol. Results were compared to those obtained operating a 1% w w−1 HNO3 solution. Compared to the HNO3 reference solution, emission signals for As, B, Hg, I, P, Se and Te atomic lines were increased for the carbon containing solution. However, signal suppression was noticed for the signal emission of Ag, Al, Ba, Be, Ca, Cd, Co, Cr, Cs, Eu, Fe, Ga, Ge, K, Ho, In, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Ni, Pb, Pd, Pr, Pt, Re, Rh, S, Sb, Sc, Sn, Sr, Ti, Tm, V, Y and Zr atomic lines. No measurable matrix effects within experimental uncertainties were registered for Au, Cu, Ir, Gd and Zn atomic lines. As regards Ce, Dy, Er, Nd, Sm, Tb, Th, U and Yb no clear conclusion about matrix effects was feasible due to the limited atomic emission wavelengths monitored. Experimental results showed that the intensity of matrix effects depends on both analyte ionization energy and the energy of the electronic upper level involved in the electronic transition. Matrix effects on atomic emission lines can be explained by the simultaneous occurrence of different mechanisms: (i) charge transfer reactions; (ii) collisional ionization; and (iii) collisional excitation with carbon-based species. Because these mechanisms mostly affect analyte atomic population, carbon matrix effects are more significant on the emission signal of atomic lines rather than ionic ones. Finally, the judicious analyte wavelength selection is critical to minimize carbon matrix effects for those elements for which the most sensitive wavelength is atomic (i.e., Se and alkali elements). On this regard, the selection of the internal standard should consider both the ionization energy and the energy of the electronic upper level of the analyte.

Aerosol dilution as a new sample introduction strategy for microwave-induced plasma optical emission spectrometry

A new sample introduction method using aerosol dilution for microwave-induced plasma optical emission spectrometry (MIP OES) is presented. Signal emissions from N2+ and OH species were monitored for plasma diagnostics and quantity of solvent plasma load (QSPL). The N2+/OH signal intensity ratio demonstrated that aerosol dilution is a desolvation process which can reduce the QSPL, increasing plasma energy. Efficiency of the system was observed with solutions containing the easily ionizable element (EIE) Na, without important alteration of the plasma physics at concentrations up to 5 g L−1. Atomic and ionic lines of Cr, Mn, V and Zn in saline solutions proved to have distinct variations. Despite the lower amount of analyte introduced, the LOQs of these elements were similar to the ones obtained from conventional nebulization. The analysis of two CRMs (fertilizer, NIST 695 and tomato leaves, NIST 1573a) resulted in percentage recoveries within 90–130%. Aerosol dilution in MIP OES (AD-MIP OES) brings increased robustness to the technique, once complex matrices can be introduced with the advantage of suppressing matrix interferences. Additionally, the sample is less prone to dilution error, and costs are saved due to increased life span of consumables since less sample matrix is introduced in the plasma.

Effect of light quality and tissue origin on phenolic compound accumulation and antioxidant activity in Camellia japonica calli

In Camellia japonica callus culture, the effects of light quality on the accumulation of phenolic compounds were examined. To this end, the calli were cultured under three monochrome [white (W), red (R), and blue (B)] and two mixed [red/blue (RB) and red/green/blue (RGB)] light sources. After 4 weeks of culture, fresh and dry callus weights were determined, and phenolic content was analyzed using high-performance liquid chromatography. We also examined the effects of RGB light on calli derived from four origins (leaf: CL; root: CR; petal: CP; and ovary: CO). Total phenolic and flavonoid content and DPPH radical scavenging activity were highest in calli exposed to RB and RGB. Catechin was detected only in calli exposed to mixed light (RB and RGB). Interestingly, red pigmentation development in CL and CR calli after 2 weeks of culture and organogenic calli in CR and CP samples was observed. Furthermore, expression of the phenylalanine ammonia lyase and chalcone synthase genes was found to be higher in the CR line than in other lines, and total phenolic and flavonoid content was also higher in the CR and CP lines. The findings of the present study revealed that the accumulation of phenolics and flavonoids in callus tissue varies depending on light quality, which stimulates cell division, and may thus affect the proliferation and organogenesis of C. japonica callus. We also established that the effects of light on red pigment expression and the accumulation of bioactive compounds are dependent on the tissue origin of callus material.

Interface detection from laser drilling of air plasma-sprayed thermal barrier coatings by laser-induced breakdown spectroscopy

To understand and control the laser machining process of cooling holes on thermal barrier coatings (TBCs) deposited on turbine blades, we introduced interfacial analysis based on laser-induced breakdown spectroscopy (LIBS). An integrated LIBS experimental setup was used to generate a series of craters under different laser shots to simulate the laser machining process. Based on the spectral data from LIBS, three characteristic atomic emission lines of Zr, Al, and Cr were selected for further analysis. We developed and revised a mathematical model based on laser ablation to understand the intensity variation of the three atomic emission lines. The experimental and model results confirmed a sharp intensity decrease of Zr at the ceramic layer/bond coat interface and observable intensity increases of Al and Cr at both the ceramic layer/bond coat and bond coat/substrate interfaces. We propose a first-order derivative method to further quantitatively obtain the interface location that can be used in practical applications.

Abstract 1865: Phosphoproteomic analyses identify EGFR as a critical cooperative kinase for ALK

Abstract ALK fusion oncogenes occur in ~5% of human lung adenocarcinomas. ALK tyrosine kinase inhibitors (TKIs) improve patient outcomes, but rarely achieve a complete tumor response and all patients ultimately relapse. In order to minimize or eliminate residual disease, it is crucial to understand the mechanisms that allow a survival niche for cancer cells under oncogene inhibition. Our lab has shown that EGFR signaling can mediate responses to fusion kinase inhibitors. However, the detailed signaling mechanism of EGFR and ALK in cancer cells is still not fully understood. In order to interrogate the contribution of EGFR to downstream signaling under ALK inhibition, we conducted phosphoproteomics for two ALK-driven cell lines, DFCI032 and H3122, using the ALK inhibitor crizotinib or in combination with the EGFR inhibitor gefitinib. Kinase-Substrate Enrichment Analysis (KSEA) and Phosphoproteomics Dissection Using Networks (PHOTON) analysis were used to identify whether a signaling node was functionally regulated based on substrate phosphorylation or on protein-protein interaction partner phosphorylation, respectively. Strikingly, both methods showed that EGFR was functionally downregulated by ALK inhibition. ALK was also considered functionally more downregulated under EGFR/ALK dual inhibition compared to ALK inhibition alone by KSEA analysis. These data suggest ALK and EGFR engage in overlapping signaling pathways. We speculated that based on the signaling patterns shared by EGFR and ALK, EGFR can be preferably selected by cancer cells to maintain critical downstream signaling mediated by ALK so upfront inhibition of EGFR may prevent ALK TKI resistance. Indeed, co-treatment with the pan-HER inhibitor afatinib in combination with crizotinib or certinib eliminated residual colonies in 2-week clonogenic assay and prevented resistance emergence in 6 weeks monitored by live cell imaging. To investigate the resistance mechanism induced by dual ALK/EGFR inhibition, we generated resistant cells by exposing H3122 to a fixed high dose of crizotinib alone (H3122-CR) or crizotinib plus afatinib (H3122-CAR). Resistance to combination therapy was once again delayed in generating H3122-CAR cells, which took ~6 months as compared to ~3 months for H3122-CR cells (n=2 for CAR and n=3 for CR cell lines). Interestingly, FAK phosphorylation was increased in H3122-CAR cells compared to H3122-CR cells (and parental cells). Although FAK inhibitors modestly re-sensitize H3122-CAR cells to ALK inhibition, the distinct signaling alterations between H3122-CAR and H3122-CR cells suggest that that cancer cells are forced to reprogram signaling under dual ALK/EGFR inhibition compared to ALK inhibition alone. Collectively, EGFR and ALK dual inhibition can significantly delay or prevent the emergence of ALK TKI resistance by suppressing critical overlapping signaling pathways and promotes signaling reprogramming in cancer cells. Citation Format: Nan Chen, Anh T. Le, Andrea E. Doak, Guolin Zhang, Bin Fang, Eric B. Haura, Robert C. Doebele. Phosphoproteomic analyses identify EGFR as a critical cooperative kinase for ALK [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1865.

Elemental analysis of sage (herb) using calibration-free laser-induced breakdown spectroscopy.

In this work, laser-induced breakdown spectroscopy (LIBS) has been used for the quantitative and qualitative analysis of the sage sample using the calibration-free LIBS (CF-LIBS) technique. The sage plasma is generated by focusing the second harmonics (532 nm) of a Q-switched Nd:YAG laser with a repetition rate of 10 Hz and pulse duration of 5 ns. The emission spectra are recorded using a LIBS 2000 detection system spectrometer consisting of five high-resolution spectrometers covering a wavelength range from 200 to 720 nm. The optical emission spectra of the sage sample reveal the spectral lines of Fe, Ca, Ti, Co, Mn, Ni, and Cr. The plasma temperature and electron number density of the neutral spectral lines of the pertinent elements have been deduced using the Boltzmann plot and Stark-broadening line profile method, with average values 8855±885K and 3.89×1016cm-3, respectively. The average values of the plasma parameters were used for the quantification of the detected elements in the sample. Based on the calibration-free method, the measured results demonstrate that Fe is the major constituent in the sample, having a percentage concentration of 48.1%, while the remaining elements are Ca, Ti, Co, Mn, Ni, and Cr, with percentage concentrations 0.7%, 5.3%, 8%, 11%, 12.3%, and 14.6%, respectively. This study demonstrates the feasibility of LIBS for the compositional analysis of major and trace elements present in the plant samples and its further applications in medicine.

The properties of cm–sized iron meteoroids

We collected meteors with iron spectra observed by the newly developed Spectral Digital Autonomous Fireball Observatories (SDAFO). SDAFOs are run within the European Fireball Network and extend the spectral observation of this network. Iron meteoroids can be distinguished using their spectra by the absence of lines of Na, Mg, Cr, Ca, and other usually bright lines of meteoritic origin.Among 220 fireball spectra that were observed by SDAFOs in 2015–2019 and that showed at least three spectral lines, eight were meteors with iron spectra. We added to the collection one additional iron meteor, which was observed with Digital Autonomous Observatories (DAFO: non–spectral cameras), the iron spectrum of which was observed with the spectral cameras of the AMOS Network (Matlovič et al., 2019).We present atmospheric trajectories, light curves, and heliocentric orbits of these iron fireballs. The orbits are asteroidal, or Sun approaching, and show diversity similar to those of mm–sized iron meteoroids. The inclinations vary from nearly zero up to ≈70∘. The maximum brightness of all fireballs was between magnitude −6 and −10, corresponding to meteoroid diameters about 1–4 ​cm. Seven fireballs were classified as type IIIA, and two fireballs were classified as type IIIB in the classification of Ceplecha and McCrosky (1976), pointing, at least formally, to fragile bodies comparable in strength to cometary meteoroids.The newly developed model of ablation of small iron meteoroids (Čapek et al., 2019) is based on the spraying of liquid iron from the meteoroid surface. The model was able to derive unambiguous physical properties only for some of the studied cm-sized bodies. Another model, the semi–empirical model of meteoroid fragmentation, was used to fit the light curves. The erosion included in the model was able to fit the light curves by manually adjusting erosion parameters. To describe the sudden drop at the end of the light curve, it was necessary to progressively increase the erosion coefficient and decrease fragment masses along the trajectory.