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The far-infrared absorption spectrum of monodeuterated water vapor, HD16O, is analyzed using three high-sensitivity absorption spectra recorded by high-resolution Fourier transform spectroscopy at the SOLEIL synchrotron facility. The gas sample was obtained using a 1:1 mixture of H2O and D2O leading to a HDO abundance close to 50%. The room temperature spectra recorded in the 50–720 cm−1 range cover most of the rotational band. The sensitivity of the recordings allows for lowering by three orders of magnitude the detectivity threshold of previous absorption studies in the region. Line centers are determined with a typical accuracy of 5 × 10−5 cm−1 for well-isolated lines. The combined line list of 8522 water lines is assigned to 9186 transitions of the nine stable water isotopologues (H2XO, HDXO, and D2XO with X = 16, 17, and 18). Regarding the HD16O isotopologue, a total of 2443 transitions are presently assigned while about 530 absorption transitions were available prior to our SOLEIL recordings. The comparison with the HITRAN list of HD16O transitions is discussed in detail. The obtained set of accurate HD16O transition frequencies is merged with literature sources to generate a set of 1121 accurate empirical rotation–vibration energies for the first five vibrational states (000), (010), (100), (020), and (001). The comparison to the previous dataset from an IUPAC task group illustrates a gain in the average energy accuracy by more than one order of magnitude. Based on these levels, a recommended list of transitions between the first five vibrational states is proposed for HD16O in the 0–4650 cm−1 frequency range.

Monodeuterated methane (CH3D) contributes greatly to absorption in the 1.58 μm methane transparency window. The spectrum is dominated by the 3ν2 band near 6430 cm−1, which is observed in natural methane and used for a number of planetary applications, such as the determination of the D/H ratio. In this work, we analyze the CH3D spectrum recorded by high-sensitivity differential absorption spectroscopy in the 6099–6530 cm−1 region, both at room temperature and at 81 K. Following a first contribution to this topic by Lu et al., the room-temperature line list is elaborated (11,189 lines) and combined with the previous 81 K list (8962 lines) in order to derive about 4800 empirical lower-state energy values from the ratio of the line intensities measured at 81 K and 294 K (2T-method). Relying on the position and intensity agreements with the TheoReTS variational line list, about 2890 transitions are rovibrationally assigned to twenty bands, with fifteen of them being newly reported. Variational positions deviate from measurements by up to 2 cm−1, and the band intensities are found to be in good agreement with measurements. All the reported assignments are confirmed by Ground-State Combination Difference (GSCD) relations; i.e., all the upper-state energies (about 1370 in total) have coinciding determinations through several transitions (up to 8). The energy values, determined with a typical uncertainty of 10−3 cm−1, are compared to their empirical and variational counterparts. The intensity sum of the transitions assigned between 6190 and 6530 cm−1 represents 76.9 and 90.0% of the total experimental intensities at 294 K and 81 K, respectively.

Abstract Tissues are complex environments where different cell types are in constant interaction with each other and with non-cellular components. Preserving the spatial context during proteomics analyses of tissue samples has become an important objective for different applications, one of the most important being the investigation of the tumor microenvironment. Here, we describe a multiplexed protein biomarker detection method on the COMET instrument, coined sequential ImmunoFluorescence (seqIF). The fully automated method uses successive applications of antibody incubation and elution, and in-situ imaging enabled by an integrated microscope and a microfluidic chip that provides optimized optical access to the sample. We show seqIF data on different sample types such as tumor and healthy tissue, including 40-plex on a single tissue section that is obtained in less than 24 h, using off-the-shelf antibodies. We also present extensive characterization of the developed method, including elution efficiency, epitope stability, repeatability and reproducibility, signal uniformity, and dynamic range, in addition to marker and panel optimization strategies. The streamlined workflow using off-the-shelf antibodies, data quality enabling downstream analysis, and ease of reaching hyperplex levels make seqIF suitable for immune-oncology research and other disciplines requiring spatial analysis, paving the way for its adoption in clinical settings.

Three electric quadrupole transitions in the second overtone band of D2 are newly measured by comb-referenced cavity ring down spectroscopy around 1.18 µm. These extremely weak transitions (line intensities smaller than 10−29 cm/molecule) are the first to be detected in the (3–0) band of D2. The spectra of the O(3), O(2), and Q(2) lines near 8321, 8446, and 8607 cm−1, respectively, are recorded at room temperature for pressure values ranging between 100 and 600 Torr. Accurate transition frequencies and line intensities of the three D2 transitions are determined from a line fitting procedure using beyond-Voigt profiles, including strong Dicke narrowing. Considering statistical fit errors and possible biases due to the interference with water lines (which are six orders of magnitude stronger than the studied D2 lines), total uncertainties on the frequencies extrapolated at zero pressure are estimated below 14 MHz (∼4.7 × 10−4 cm−1). The derived experimental frequencies and intensities are compared to ab initio values. An overall agreement is achieved, confirming the positional accuracy of the most advanced theoretical calculations. [ABSTRACT FROM AUTHOR]

The far-infrared absorption spectrum of monodeuterated water vapor, HD16O, is analyzed using three high-sensitivity absorption spectra recorded by high-resolution Fourier transform spectroscopy at the SOLEIL synchrotron facility. The gas sample was obtained using a 1:1 mixture of H2O and D2O leading to a HDO abundance close to 50%. The room temperature spectra recorded in the 50–720 cm−1 range cover most of the rotational band. The sensitivity of the recordings allows for lowering by three orders of magnitude the detectivity threshold of previous absorption studies in the region. Line centers are determined with a typical accuracy of 5 × 10−5 cm−1 for well-isolated lines. The combined line list of 8522 water lines is assigned to 9186 transitions of the nine stable water isotopologues (H2XO, HDXO, and D2XO with X = 16, 17, and 18). Regarding the HD16O isotopologue, a total of 2443 transitions are presently assigned while about 530 absorption transitions were available prior to our SOLEIL recordings. The comparison with the HITRAN list of HD16O transitions is discussed in detail. The obtained set of accurate HD16O transition frequencies is merged with literature sources to generate a set of 1121 accurate empirical rotation–vibration energies for the first five vibrational states (000), (010), (100), (020), and (001). The comparison to the previous dataset from an IUPAC task group illustrates a gain in the average energy accuracy by more than one order of magnitude. Based on these levels, a recommended list of transitions between the first five vibrational states is proposed for HD16O in the 0–4650 cm−1 frequency range. [ABSTRACT FROM AUTHOR]

Monodeuterated methane (CH3D) contributes greatly to absorption in the 1.58 μm methane transparency window. The spectrum is dominated by the 3ν2 band near 6430 cm−1, which is observed in natural methane and used for a number of planetary applications, such as the determination of the D/H ratio. In this work, we analyze the CH3D spectrum recorded by high-sensitivity differential absorption spectroscopy in the 6099–6530 cm−1 region, both at room temperature and at 81 K. Following a first contribution to this topic by Lu et al., the room-temperature line list is elaborated (11,189 lines) and combined with the previous 81 K list (8962 lines) in order to derive about 4800 empirical lower-state energy values from the ratio of the line intensities measured at 81 K and 294 K (2T-method). Relying on the position and intensity agreements with the TheoReTS variational line list, about 2890 transitions are rovibrationally assigned to twenty bands, with fifteen of them being newly reported. Variational positions deviate from measurements by up to 2 cm−1, and the band intensities are found to be in good agreement with measurements. All the reported assignments are confirmed by Ground-State Combination Difference (GSCD) relations; i.e., all the upper-state energies (about 1370 in total) have coinciding determinations through several transitions (up to 8). The energy values, determined with a typical uncertainty of 10−3 cm−1, are compared to their empirical and variational counterparts. The intensity sum of the transitions assigned between 6190 and 6530 cm−1 represents 76.9 and 90.0% of the total experimental intensities at 294 K and 81 K, respectively. [ABSTRACT FROM AUTHOR]