Spatial Beam Self-Cleaning in Bi-Tapered Multimode Fibers

We report the spatial beam self-cleaning in bi-tapered conventional multimode fibers (MMFs) with different tapered lengths. Through the introduction of the bi-tapered structure in MMFs, the input beam with poor beam quality from a high-power fiber laser can be converted to a centered, bell-shaped beam in a short length, due to the strengthened nonlinear modes coupling. It is found that the bi-tapered MMF with longer tapered length at the same waist diameter shows better beam self-cleaning effect and larger spectral broadening. The obtained results offer a new method to improve the beam quality of high-power laser at low cost. Furthermore, it may be interesting for manufacturing bi-tapered MMF-based devices to obtain the quasi-fundamental mode beam in spatiotemporal mode-locked fiber lasers.

Quantum enhanced multiple-phase estimation with multi-mode N00N states

Quantum metrology can achieve enhanced sensitivity for estimating unknown parameters beyond the standard quantum limit. Recently, multiple-phase estimation exploiting quantum resources has attracted intensive interest for its applications in quantum imaging and sensor networks. For multiple-phase estimation, the amount of enhanced sensitivity is dependent on quantum probe states, and multi-mode N00N states are known to be a key resource for this. However, its experimental demonstration has been missing so far since generating such states is highly challenging. Here, we report generation of multi-mode N00N states and experimental demonstration of quantum enhanced multiple-phase estimation using the multi-mode N00N states. In particular, we show that the quantum Cramer-Rao bound can be saturated using our two-photon four-mode N00N state and measurement scheme using a 4 × 4 multi-mode beam splitter. Our multiple-phase estimation strategy provides a faithful platform to investigate multiple parameter estimation scenarios.

Data-independent acquisition protease-multiplexing enables increased proteome sequence coverage across multiple fragmentation modes

The use of multiple proteases has been shown to increase protein sequence coverage in proteomics experiments, however due to the additional analysis time required, it has not been widely adapted in routine data-dependent acquisition (DDA) proteomic workflows. Alternatively, data-independent acquisition (DIA) has the potential to analyze multiplexed samples from different protease digests, but has been primarily optimized for fragmenting tryptic peptides. Here we evaluate a DIA multiplexing approach that combines three proteolytic digests (Trypsin, AspN, and GluC) into a single sample. We first optimize data acquisition conditions for each protease individually with both the canonical DIA fragmentation mode (beam type CID), as well as resonance excitation CID, to determine optimal consensus conditions across proteases. Next, we demonstrate that application of these conditions to a protease-multiplexed sample of human peptides results in similar protein identifications and quantitative performance as compared to trypsin alone, but enables up to a 63% increase in peptide detections, and a 27% increase non-redundant amino acid detections. Importantly, this resulted in 100% sequence coverage for numerous proteins, suggesting the utility of this approach in applications where sequence coverage is critical, such as proteoform analysis.

A new spring barley variety ‘In Memory of Dudin’

The purpose of the research is to conduct a comprehensive assessment of the new spring barley variety ‘in Memory of Dudin’ on economically valuable signs. Studies were carried out in 2016-2019. The spring barley variety “in Memory of Dudin’ was created by the method of directional individual selection from the variant with treatment of spring barley variety ‘Bios 1’ with laser red light (wavelength 632.8 nm, continuous irradiation mode, beam power density 0.3 mW/cm2) for 60 minutes, followed by soaking in a solution of sodium carbonate with a concentration of 0,1n for 12 hours. Ear of the plant has average length 8.9 cm, the number of spikelets and the grain in the ear are medium (25.6 pcs. and 24.3 pcs. respectively). The 1000-grain weight is high - 49.2 g. Culm has an average length of 72.4 cm. The average yield over the years of the study was 4.6 tons/ha, the maximum one - 7.02 tons/ha in 2019. Dry matter ash content 2.2%, fiber content 3.65%, starch content 52.61%, fat content 1.65%, protein content 10.19%; extractability 77.0%. The variety ripens 4-7 days earlier than the standard. Based on a comprehensive assessment, the spring barley variety of “in Memory of Dudin’ was transferred to the State Variety Test in 2020.