In this paper, we report 4 different saturable absorbers based on 4 transition metal dichalcogenides (MoS(2), MoSe(2), WS(2), WSe(2)) and utilize them to Q-switch a ring-cavity fiber laser with identical cavity configuration. It is found that MoSe(2) exhibits highest modulation depth with similar preparation process among four saturable absorbers. Q-switching operation performance is compared from the aspects of RF spectrum, optical spectrum, repetition rate and pulse duration. WS(2) Q-switched fiber laser generates the most stable pulse trains compared to other 3 fiber lasers. These results demonstrate the feasibility of TMDs to Q-switch fiber laser effectively and provide a meaningful reference for further research in nonlinear fiber optics with these TMDs materials.
A Bayesian statistical analysis using redshift space distortions data is performed to test a model of Symmetric Teleparallel Gravity where gravity is non-metrical. The cosmological background mimics a $\Lambda$CDM evolution but differences arise in the perturbations. The linear matter fluctuations are numerically evolved and the study of the growth rate of structures is analysed in this cosmological setting. The best fit parameters reveal that the $\sigma_8$ tension between Planck and Large Scale Structure data can be alleviated within this framework.
Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.
We consider f(Q) extended symmetric teleparallel cosmologies, where Q is the non-metricity scalar, and constrain its functional form through the order reduction method. By using this technique, we are able to reduce and integrate the field equations and thus to select the corresponding models giving rise to bouncing cosmology. The selected Lagrangian is then used to develop the Hamiltonian formalism and to obtain the Wave Function of the Universe which suggests that classical observable universes can be recovered according to the Hartle Criterion.
Very low frequency communication systems (3 kHz–30 kHz) enable applications not feasible at higher frequencies. However, the highest radiation efficiency antennas require size at the scale of the wavelength (here, >1 km), making portable transmitters extremely challenging. Facilitating transmitters at the 10 cm scale, we demonstrate an ultra-low loss lithium niobate piezoelectric electric dipole driven at acoustic resonance that radiates with greater than 300x higher efficiency compared to the previous state of the art at a comparable electrical size. A piezoelectric radiating element eliminates the need for large impedance matching networks as it self-resonates at the acoustic wavelength. Temporal modulation of this resonance demonstrates a device bandwidth greater than 83x beyond the conventional Bode-Fano limit, thus increasing the transmitter bitrate while still minimizing losses. These results will open new applications for portable, electrically small antennas. Designing high radiation efficiency antennas for portable transmitters in low frequency communication systems remains a challenge. Here, the authors report on using piezoelectricity to more efficiently radiate while achieving a bandwidth eighty three times higher than the passive Bode-Fano limit.
We investigate the impact on cosmological observables of $f(Q)$-gravity, a specific class of modified gravity models in which gravity is described by the nonmetricity scalar, $Q$. In particular we focus on a specific model which is indistinguishable from the $\mathrm{\ensuremath{\Lambda}}$-cold-dark-matter ($\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$) model at the background level, while showing peculiar and measurable signatures at linear perturbation level. These are attributed to a time-dependent Planck mass and are regulated by a single dimensionless parameter, $\ensuremath{\alpha}$. In comparison to the $\mathrm{\ensuremath{\Lambda}}\mathrm{CDM}$ model, we find for positive values of $\ensuremath{\alpha}$ a suppressed matter power spectrum and lensing effect on the cosmic microwave background radiation (CMB) angular power spectrum and an enhanced integrated-Sachs-Wolfe tail of CMB temperature anisotropies. The opposite behaviors are present when the $\ensuremath{\alpha}$ parameter is negative. We also investigate the modified gravitational waves (GWs) propagation and show the prediction of the GWs luminosity distance compared to the standard electromagnetic one. Finally, we infer the accuracy on the free parameter of the model with standard sirens at future GWs detectors.
Solar- powered irrigation systems (SPIS) are instruments for sustainable energy transition in agriculture. Despite the government of India's efforts, the adoption of SPIS has remained low. This paper uses the Q method to examine shared stakeholder views on the challenges of increasing SPIS adoption. The aim is to understand barriers to and drivers for SPIS adoption, and the necessary institutional setting to scale up adoption. To capture the discourse on challenges to SPIS adoption, a Q sample of 20 statements was extracted after stakeholder interviews and expert ratings. The statements were Q sorted by 22 respondents across SPIS stakeholder groups. Factor analysis identifies two distinct perspectives on constraints to expanding SPIS: (1) economic and financial barriers; and (2) institutional and governance challenges. This calls for re-framing SPIS from the incentive side of things and convergence across concerned implementing agencies.
Ana Mariya Anhel, Lorea Alejaldre, Ángel Goñi-Moreno
This protocol is meant to select samples from one or more source plate(s) that has 2 different selecting conditions: one condition gives higher values and the other lower values (i.e different fluorescence values or OD600nm values to indicate growth/no growth). From these selected samples this protocol creates final plates with given reactive(s) (i.e media with different antibiotics or inductors) and inoculates samples from a source plate.In our laboratory this protocol has been used as part of the "High-throughput workflow for the genotypic characterization of transposon insertion library variants" also available in protocols.io to select variants to keep as glycerol stock and perform subsequent PCRs to assign a genotype. In particular, this protocol is used for selecting bacterial variants grown in two 96-well plates with different antibiotics by measuring OD600nm after overnight growth. Bacterial variants are selected based on growth/no growth and inoculated in final plates. Final plates consist of 96-well format plates with molecular biology grade water to perform subsequent PCR on selected samples and 2 stock plates containing 30% glycerol to perform bacterial stocks of selected samples. To run this protocol a python script for an Opentrons OT-2 robot and an excel file with several variables are needed . This protocol is a set of instructions or description of the LAP repository entry LAP-ColonyCounterSelection-OT2-2.0.0 You can find the script and complementary information for this specific version of the protocol in this LAP entry link and GitHub Link to LAP entry documents The major changes from previous version are: Change of name variableAPI Name Rack 15mL Falcon Reactiveswhich is called nowAPI Name Rack Falcon Reactives The program now accepts falcon tubes and tube racks of 15ml or 50ml. It does not accept mix tube racks. Description of robot and protocol setup in a separate protocols.io entry (Setting and Customizing OT-2 for LAP Entries) Sheets that corresponds to the map of values to compare now need to have the name of the rows and columns of the source labware
Zusammenfassung Der vorliegende Beitrag untersucht die IT/OT-Konvergenz in 31 überwiegend großen deutschen Unternehmen. Er stellt ein „IT/OT-Governance-Framework“ als spezifisches Modell für eine erfolgreiche Konvergenzumsetzung vor. Die Analyse zeigt heterogene Reifegrade der Konvergenzumsetzung in den untersuchten Unternehmen, die sich mehrheitlich noch am Anfang oder in der Implementierungsphase befinden. Bevorzugt wird eine enge Zusammenarbeit zwischen IT und OT, jedoch ohne vollständige Übernahme des OT-Bereichs durch die IT. Ein IT/OT-Tandem aus CIO und zentraler OT-Rolle wird als ideal für die Verantwortungsübernahme angesehen. Aus den Interviews wurden sechs konkrete Umsetzungsempfehlungen abgeleitet, die in das entwickelte IT/OT-Governance-Framework eingeflossen sind. Dazu gehören die Sicherstellung der Top-Managment-Unterstützung, die Nutzung von Security als Treiber, die Einführung einer zentralen OT-Rolle, die räumliche Annäherung von IT- und OT-Teams, das kontinuierliche Aufzeigen der Mehrwerte der Konvergenz und ein schrittweises Vorgehen bei der Umsetzung.
A bstractResults are reported from a search for supersymmetric particles in the final state with multiple jets and large missing transverse momentum. The search uses a sample of proton-proton collisions at s$$ \sqrt{s} $$ = 13 TeV collected with the CMS detector in 2016–2018, corresponding to an integrated luminosity of 137 fb−1, representing essentially the full LHC Run 2 data sample. The analysis is performed in a four-dimensional search region defined in terms of the number of jets, the number of tagged bottom quark jets, the scalar sum of jet transverse momenta, and the magnitude of the vector sum of jet transverse momenta. No significant excess in the event yield is observed relative to the expected background contributions from standard model processes. Limits on the pair production of gluinos and squarks are obtained in the framework of simplified models for supersymmetric particle production and decay processes. Assuming the lightest supersymmetric particle to be a neutralino, lower limits on the gluino mass as large as 2000 to 2310 GeV are obtained at 95% confidence level, while lower limits on the squark mass as large as 1190 to 1630 GeV are obtained, depending on the production scenario.