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At least 289 records · Page 16

Development of a Massive, Highly Multiplexible, Phonon-Mediated Particle Detector Using Kinetic Inductance Detectors

Here, we present a status update on the development of a phonon-mediated particle detector using kinetic inductance detector (KID). The design is intended for \(\mathscr {O}(1)\) kg substrate, using \(\mathscr {O}(10^{2})\) KIDs on a single readout line, to image the athermal phonon distribution at < 1 mm position resolution and \(\mathscr {O}(10)\) eV energy resolution. The design specification is set by the need to improve position reconstruction fidelity while maintaining low energy threshold for future rare-event searches such as for low-mass dark matter. Furthermore, we report on the design, which shows negligible crosstalk and > 95% inductor current uniformity, using the coplanar waveguide feedline, ground shield, and a new class of KIDs with symmetric coplanar stripline (sCPS) inductor. The multiplexing is designed upon the frequency-geometry relation we develop for the sCPS KIDs. We introduce the fabrications of the Nb RF assessment prototypes and the high phonon collection efficiency Al–Nb devices. We achieve \(\lesssim \) 0.07% frequency displacement on a 80-KID RF assessment prototype, and the result indicates that we may place more than 180 resonances in our 0.4 GHz readout band with minimal frequency misordering. The coupling quality factors are \(\sim \) 10 \(^{5}\) as designed. Finally, we update our work in progress in fabricating the \(\mathscr {O}(10^{2})\) KID, bi-material, \(\mathscr {O}(1)\) kg detectors, and the expected position and energy resolutions.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Signatures of Thermal and Electrical Crosstalk in a Microwave Multiplexed Hard X-ray Transition Edge Sensor Array

We investigate the crosstalk between Transition-Edge Sensor (TES) pixels in a 24-pixel hard X-ray spectrometer array fabricated at the Advanced Photon Source, Argonne National Laboratory. Analysis shows thermal cross talk, possibly associated with insufficient thermalization, and rare but larger in magnitude electrical crosstalk between specific perpetrator-victim pixel combinations, potentially due to defects in the bias wiring or microwave multiplexing circuit. We use a method based on group-triggering and averaging to isolate the crosstalk response despite only having access to X-ray photon illumination uniform across the entire array. This allows us to identify thermal and electrical crosstalk between pixel pairs in repeated measurements to the level of 1 part in 1000 or better. In the array under study, the magnitude of observed crosstalk is small but comparable to the resolving power of this pixel design (E/Delta E similar to\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E/\Delta {}E \sim$$\end{document} 1000 at 20 keV) and so potentially responsible for a degradation in energy resolution of the array at high incident photon rates. Having proven the methods to identify and quantify crosstalk in our setup, we can now consider mitigations.

Triamkitsawat, Panthita↗

Suppression of four-wave mixing in a 22 × 10 Gbps dense wavelength division multiplexed system by linearly chirped fiber Bragg gratings

A scheme comprising two linearly chirped fiber Bragg gratings (LCFBGs) is proposed to suppress four-wave mixing (FWM) effects in a 22×10 Gbps dense wavelength division multiplexed (DWDM) system employing dispersion shifted fiber with 0.2 nm channel spacing. The FWM reduction in our proposed scheme has been studied by varying the input signal power per channel from − 2 to + 10 dBm. The parameters of LCFBGs are optimized to obtain a maximum quality factor for all 22 channels. The proposed method is effective even at high input power (10 dBm) and provides a simple, cost effective way to improve the transmission performance in DWDM system.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Minimum shift keying based protection mode capable wavelength division multiplexed passive optical network optical overlay system

We explored the functioning of an optical overlay of multicast and unicast data streams on a survival wavelength division multiplexed passive optical network using intensity and minimum shift keying modulation for both single and multiuser. In optical line terminal, using a sinusoidal clock, optical subcarriers are generated not only to carry the multicast and unicast data streams simultaneously but also in case of fiber failure, protection mode is enabled to carry the data streams smoothly. Here, 10 Gbps downstream multicast in normal mode and unicast signals both in normal and protection mode are transmitted error-free through 30 km dispersion shifted fiber. In both the cases 10 Gbps upstream signal is modulated and sent back to the optical line terminal. For single user nearly similar power penalty is witnessed for downstream unicast as well as re-modulated upstream data in both the conditions and also when multicast data is disabled. The power penalties between single and multiuser for both the modes are found to be approximately 0.06, 0.42 and 0.7 dB for unicast MSK, multicast and upstream respectively.

36 MATERIALS SCIENCE↗

Trace double-component gas sensor in photoacoustic spectroscopy based on frequency division multiplexing

In this paper, we demonstrated a trace double-component gas detection system based on frequency division multiplexing using two-way distributed feedback laser diode (DFB-LD) as the excitation laser source. In the frequency response range of photoacoustic spectroscopy (PAS) cell, this detection system could detect the second harmonics of different frequencies f{sub 0} and f{sub 1}, which were excited by the gas absorption using the two wavelengths of DFB-LD at modulation frequencies f{sub 0}/2 and f{sub 1}/2. Unlike previous double-component gas sensor, these two DFB-LDs connected into the both ends of PAS cell without optical fiber coupler could effectively improve the excited light intensity and simplify the system structure. This feature allowed the trace detection of double-component gas of mixed-methane (CH{sub 4}) and water (H{sub 2}O) vapor with a low detection limits 11.055 ppm and 885 ppb, respectively. Additionally, the linear responses to the gas concentration were achieved 0.9986 and 0.9997, and it exhibited potentially as an effective detection system for complex gas component.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Enhancing capacity of optical links using polarization multiplexing

5G mobile networks targets wireless connection capacity up to 10 Gb/s. For this purpose, we propose a method to considerably increase capacity. In this paper first, we show how to compensate the effects of polarization mode dispersion (PMD) in systems with double polarizations where PMD in such systems could cause fluctuations in optical transmission due to crosstalk and cross phase modulation. Second, we show how to enhance system capacity benefiting from polarization multiplexing (POL-MUX) technique which can provide double bandwidth efficiency. Based on the simulation results, we have achieved optimum system performance and we were able to reduce the PMD effect using pre- and post-compensation. We also have improved the POL-MUX technique using coherent detection in case of 16/64 QAM modulations. The results were achieved by implementing polarization controllers, polarization beam combiners and splitters, as well as polarization phase shifters.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Profiling of bioactive lipids in different dendritic cell subsets using an improved multiplex quantitative LC-MS/MS method

Highlights: • We improved a LC-MS/MS method to measure many mediators simultaneously. • Conventional DCs produce inflammatory lipids (leukotrienes) preferentially. • RA-DCs produce PGI{sub 2}, PGE{sub 2}, and TXA{sub 2} preferentially. Lipids are an energy source and key components of the cell membrane; however, they are also bioactive mediators of physiological and pathophysiological phenomena. Quantification of bioactive lipids is not easy because they have diverse chemical properties and are present in trace amounts. Here, we improved a multiplex method of quantifying bioactive lipids, thereby enabling measurement of 90 compounds simultaneously. We then used this system to quantify bioactive lipids produced by two subsets of dendritic cells (DCs): all-trans retinoic acid-treated DCs (RA-DCs) (a type of tolerogenic DC (tDC)) and conventional DCs (cDCs). We found that cDCs produced inflammatory lipid mediators such as leukotrienes, whereas RA-DCs produced anti-inflammatory lipid mediators such as prostaglandin I{sub 2}. Consistent with this, cDCs expressed larger amounts of mRNA encoding 5-lipoxygenase and LTA{sub 4} hydrolase (both responsible for leukotriene biosynthesis) and RA-DCs produced larger amounts of mRNA encoding prostaglandin I{sub 2} synthase. Taken together, the results suggest that the method is useful for clarifying the roles of bioactive lipids during immune responses.

60 APPLIED LIFE SCIENCES↗

Monte–Carlo ray-tracing studies of multiplexed prismatic graphite analyzers for the cold-neutron triple-axis spectrometer at the High Flux Isotope Reactor

A modern cold triple-axis spectrometer to study quantum condensed matter systems is planned for the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. Here, we describe the conceptual principles and design of a secondary spectrometer using a multiplexed, prismatic analyzer system relying on graphite crystals and inspired by the successful implementation of the Continuous Angle Multiple Energy Analysis (CAMEA) spectrometers at the Paul Scherrer Institute. This project is currently known as MANTA for Multi-Analyzer Neutron Triple-Axis. Here, we report Monte-Carlo ray-tracing simulations on a simple but realistic sample scattering kernel to further illustrate the prismatic analyzer concept’s workings, calibration, and performance. Then, we introduce a new statistical analysis approach based on the prismatic analyzer concept to improve the number of final energies measured on the spectrometer. We also study possible evolutions in the CAMEA design relevant for MANTA.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Design and development of a probe-based multiplexed multi-species absorption spectroscopy sensor for characterizing transient gas-parameter distributions in the intake systems of I.C. engines

We designed and developed a 4-probe multiplexed multi-species absorption spectroscopy sensor system for gas property measurements on the intake side of commercial multi-cylinder internal-combustion (I.C.) engines; the resulting cycle- and cylinder-resolved concentration, temperature and pressure measurements are applicable for assessing spatial and temporal variations in the recirculated exhaust gas (EGR) distribution at various locations along the intake gas path, which in turn is relevant to assessing cylinder charge uniformity, control strategies, and CFD models. Furthermore, the diagnostic is based on absorption spectroscopy and includes an H 2 O absorption system (utilizing a 1.39 m distributed feedback (DFB) diode laser) for measuring gas temperature, pressure, and H 2 O concentration, and a CO 2 absorption system (utilizing a 2.7 m DFB laser) for measuring CO 2 concentration. The various lasers, optical components and detectors were housed in an instrument box, and the 1.39- m and 2.7- m lasers were guided to and from the engine-mounted probes via optical fibers and hollow waveguides, respectively. The 5kHz measurement bandwidth allows for near-crank angle resolved measurements, with a resolution of 1.2 crank angle degrees at 1000 RPM. Our use of compact stainless steel measurement probes enables simultaneous multi-point measurements at various locations on the engine with minimal changes to the base engine hardware; in addition to resolving large-scale spatial variations via simultaneous multi-probe measurements, local spatial gradients can be resolved by translating individual probes. Along with details of various sensor design features and performance, we also demonstrate validation of the spectral parameters of the associated CO 2 absorption transitions using both a multi-pass heated cell and the sensor probes.

33 ADVANCED PROPULSION SYSTEMS↗

A quantitative multiplex nuclease protection assay reveals immunotoxicity gene expression profiles in the rabbit model for vaginal drug safety evaluation

Any vaginal product that alters the mucosal environment and impairs the immune barrier increases the risk of sexually transmitted infections, especially HIV infection, which thrives on mucosal damage and inflammation. The FDA-recommended rabbit vaginal irritation (RVI) model serves as a first line selection tool for vaginal products; however, for decades it has been limited to histopathology scoring, insufficient to select safe anti-HIV microbicides. In this study we incorporate to the RVI model a novel quantitative nuclease protection assay (qNPA) to quantify mRNA levels of 25 genes representing leukocyte differentiation markers, toll-like receptors (TLR), cytokines, chemokines, epithelial repair, microbicidal and vascular markers, by designing two multiplex arrays. Tissue sections were obtained from 36 rabbits (6 per treatment arm) after 14 daily applications of a placebo gel, saline, 4% nonoxynol-9 (N-9), and three combinations of the anti-HIV microbicides tenofovir (TFV) and UC781 in escalating concentrations (highest: 10% TFV + 2.5%UC781). Results showed that increased expression levels of toll-like receptor (TLR)-4, interleukin (IL)-1β, CXCL8, epithelial membrane protein (EMP)-1 (P < 0.05), and decreased levels of TLR2 (P < 0.05), TLR3 and bactericidal permeability increasing protein (BPI) (P < 0.001) were associated with cervicovaginal mucosal alteration (histopathology). Seven markers showed a significant linear trend predicting epithelial damage (up with CD4, IL-1β, CXCL8, CCL2, CCL21, EMP1 and down with BPI). Despite the low tissue damage RVI scores, the high-dose microbicide combination gel caused activation of HIV host cells (SLC and CD4) while N-9 caused proinflammatory gene upregulation (IL-8 and TLR4) suggesting a potential for increasing risk of HIV via different mechanisms depending on the chemical nature of the test product. - Highlights: • A transcriptome nuclease protection assay assessed microbicides for vaginal safety. • Biomarkers were correlated with histopathology in paraffin-embedded rabbit tissues. • Compounds differed by effects on putative pathways of increased risk of HIV. • Nonsoxynol-9 caused inflammatory tissue damage involving TLR4 and IL-8. • An antiretroviral combination stimulated immune cells evidenced by SLC and CD4.

60 APPLIED LIFE SCIENCES↗

Internal Standard Triggered-Parallel Reaction Monitoring Mass Spectrometry Enables Multiplexed Quantification of Candidate Biomarkers in Plasma

Despite advances in proteomic technologies, clinical translation of plasma biomarkers remains low, partly due to a major bottleneck between the discovery of candidate biomarkers and costly clinical validation studies. Due to a dearth of multiplexable assays, generally only a few candidate biomarkers are tested, and the validation success rate is accordingly low. Previously, mass spectrometry-based approaches have been used to fill this gap but feature poor quantitative performance and were generally limited to hundreds of proteins. Here, we demonstrate the capability of an internal standard triggered-parallel reaction monitoring (IS-PRM) assay to greatly expand the numbers of candidates that can be tested with improved quantitative performance. The assay couples immunodepletion and fractionation with IS-PRM and was developed and implemented in human plasma to quantify 5176 peptides representing 1314 breast cancer biomarker candidates. Characterization of the IS-PRM assay demonstrated the precision (median % CV of 7.7%), linearity (median R 2 > 0.999 over 4 orders of magnitude), and sensitivity (median LLOQ < 1 fmol, approximately) to enable rank-ordering of candidate biomarkers for validation studies. Using three plasma pools from breast cancer patients and three control pools, 893 proteins were quantified, of which 162 candidate biomarkers were verified in at least one of the cancer pools and 22 were verified in all three cancer pools. The assay greatly expands capabilities for quantification of large numbers of proteins and is well suited for prioritization of viable candidate biomarkers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Coupling Microdroplet-Based Sample Preparation, Multiplexed Isobaric Labeling, and Nanoflow Peptide Fractionation for Deep Proteome Profiling of the Tissue Microenvironment

There is increasing interest in developing in-depth proteomic approaches for mapping tissue heterogeneity in a cell-type-specific manner to better understand and predict the function of complex biological systems such as human organs. Existing spatially resolved proteomics technologies cannot provide deep proteome coverage due to limited sensitivity and poor sample recovery. Herein, we seamlessly combined laser capture microdissection with a low-volume sample processing technology that includes a microfluidic device named microPOTS (microdroplet processing in one pot for trace samples), multiplexed isobaric labeling, and a nanoflow peptide fractionation approach. The integrated workflow allowed us to maximize proteome coverage of laser-isolated tissue samples containing nanogram levels of proteins. We demonstrated that the deep spatial proteomics platform can quantify more than 5000 unique proteins from a small-sized human pancreatic tissue pixel (∼60,000 μm2) and differentiate unique protein abundance patterns in pancreas. Furthermore, the use of the microPOTS chip eliminated the requirement for advanced microfabrication capabilities and specialized nanoliter liquid handling equipment, making it more accessible to proteomic laboratories.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

High-Throughput Single Cell Proteomics Enabled by Multiplex Isobaric Labelling in a Nanodroplet Sample Preparation Platform

Effective extension of mass spectrometry-based proteomics to single cells remains challenging. Herein we combined microfluidic nanodroplet technology with tandem mass tag (TMT) isobaric labeling to significantly improve analysis throughput and proteome coverage for single mammalian cells. Isobaric labeling facilitated multiplex analysis of single cell-sized protein quantities to a depth of ~1,600 proteins with median CV of 10.9% and correlation coefficient of 0.98. To demonstrate in-depth high throughput single cell analysis, the platform was applied to measure protein expression in 72 single cells from three murine cell populations (epithelial, immune, and endothelial cells) in <2 days instrument time with over 2,300 proteins identified. Principal component analysis grouped the single cells into three distinct populations based on protein expression with each population characterized by well-known cell-type specific markers. Our platform enables high throughput and unbiased characterization of single cell heterogeneity at the proteome level.

Dou, Maowei↗

Multiplexed photoionization mass spectrometry investigation of the O( 3 P) + propyne reaction

Here, the reaction of O( 3 P) + propyne (C 3 H 4 ) was investigated at 298 K and 4 Torr using time-resolved multiplexed photoionization mass spectrometry and a synchrotron-generated tunable vacuum ultraviolet light source. The time-resolved mass spectra of the observed products suggest five major channels under our conditions: C 2 H 3 + HCO, CH 3 + HCCO, H + CH 3 CCO, C 2 H 4 + CO, and C 2 H 2 + H 2 + CO. The relative branching ratios for these channels were found to be 1.00, (0.35 ± 0.11), (0.18 ± 0.10), (0.73 ± 0.27), and (1.31 ± 0.62). In addition, we observed signals consistent with minor production of C 3 H 3 + OH and H 2 + CH 2 CCO, although we cannot conclusively assign them as direct product channels from O( 3 P) + propyne. The direct abstraction mechanism plays only a minor role (≤1%), and we estimate that O( 3 P) addition to the central carbon of propyne accounts for 10% of products, with addition to the terminal carbon accounting for the remaining 89%. The isotopologues observed in experiments using d1-propyne (CH 3 CCD) and analysis of product branching in light of previously computed stationary points on the singlet and triplet potential energy surfaces (PESs) relevant to O( 3 P) + propyne suggest that, under our conditions, (84 ± 14)% of the observed product channels from O( 3 P) + propyne result from intersystem crossing from the initial triplet PES to the lower-lying singlet PES.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

A Multiplexed Quantitative Analysis of Germline Single Amino Acid Variants by Targeted Proteomics in Nondepleted Human Plasma

Single amino acid variants (SAAVs) in protein sequences are often a direct result of single-nucleotide polymorphisms (SNPs). Certain germline SAAVs have shown biological relevance in different disease conditions but lack precise quantification in circulation, which could hinder functional investigations and progress in biomarker development. Here, we have developed a multiplexed liquid chromatography-selected reaction monitoring (LC-SRM) assay that monitors 5 wild-type and variant peptide pairs (Complement Factor B: CFB-R32Q/R32W, Clusterin: CLU-N317H, Fetuin B: FETUB-K360R, and Kininogen: KNG1-L212P) in nondepleted human plasma. The assay was optimized for imprecision, linearity, stability, and calibration assessments with CVs of under 20%. The wild-type and variant peptide pairs were characterized in a set of healthy individual plasma samples. These target identifications were also validated by SNP genotyping with more than 99% accuracy. For all protein targets, we observed significantly lower concentrations of WT species in the presence variant peptides. In CFB, the concentration of R32Q was significantly lower than its counterpart R32W variant and WT species. Furthermore, our results distinguished phenotypes of homozygosity and heterozygosity of the SAAV presence through direct concentration level characterization. These findings provide some insights into how SAAVs affect quantitative assessments of target peptides. The assay demonstrates a platform for proteogenomic analyses with potential applications in both research and clinical settings.

genetics↗

Multiplex Evolution of Antibody Fragments Utilizing a Yeast Surface Display Platform

Advances in high-throughput synthetic biology technologies based on the CRISPR/Cas9 system have enabled a comprehensive assessment of mutations conferring desired phenotypes, as well as a better understanding of genotype-phenotype correlations in protein engineering. Engineering antibodies to enhance properties such as binding affinity and stability plays an essential role in therapeutic applications. Here we report a method, multiplex navigation of antibody structure (MINAS), that combines a CRISPR/Cas9-based trackable editing method and fluorescent-activated cell sorting (FACS) of yeast-displayed libraries. We designed mutations in all of the complementarity-determining and framework regions of a well-characterized scFv antibody and mapped the contribution of these regions to enhanced properties. We identified specific mutants that showed higher binding affinities up to 100-fold compared to the wild-type. This study expands the applicability of CRISPR/Cas9-based trackable protein engineering by combining it with a surface display platform.

59 BASIC BIOLOGICAL SCIENCES↗

Realization of a spin-wave multiplexer

Recent developments in the field of spin dynamics—like the interaction of charge and heat currents with magnons, the quasi-particles of spin waves—opens the perspective for novel information processing concepts and potential applications purely based on magnons without the need of charge transport. The challenges related to the realization of advanced concepts are the spin-wave transport in two-dimensional structures and the transfer of existing demonstrators to the micro- or even nanoscale. Here we present the experimental realization of a microstructured spin-wave multiplexer as a fundamental building block of a magnon-based logic. Our concept relies on the generation of local Oersted fields to control the magnetization configuration as well as the spin-wave dispersion relation to steer the spin-wave propagation in a Y-shaped structure. Thus, the present work illustrates unique features of magnonic transport as well as their possible utilization for potential technical applications.

Vogt, K.↗

CrY2H-seq: a massively multiplexed assay for deep-coverage interactome mapping

Broad-scale protein–protein interaction mapping is a major challenge given the cost, time, and sensitivity constraints of existing technologies. Here, we present a massively multiplexed yeast two-hybrid method, CrY2H-seq, which uses a Cre recombinase interaction reporter to intracellularly fuse the coding sequences of two interacting proteins and next-generation DNA sequencing to identify these interactions en masse. We applied CrY2H-seq to investigate sparsely annotated Arabidopsis thaliana transcription factors interactions. By performing ten independent screens testing a total of 36 million binary interaction combinations, and uncovering a network of 8,577 interactions among 1,453 transcription factors, we demonstrate CrY2H-seq's improved screening capacity, efficiency, and sensitivity over those of existing technologies. The deep-coverage network resource we call AtTFIN-1 recapitulates one-third of previously reported interactions derived from diverse methods, expands the number of known plant transcription factor interactions by three-fold, and reveals previously unknown family-specific interaction module associations with plant reproductive development, root architecture, and circadian coordination.

59 BASIC BIOLOGICAL SCIENCES↗