bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation of entangled cats from photon number states
Authors: Shringarpure S.U. , Franson J.D.
Published: January 2021

A phase-entangled cat state is created when a number state passes through a beamsplitter. This entanglement is used to violate Bell’s inequality using large Kerr media. This approach may have applications in quantum communications.
Ultrafast Vibronic Phenomena Directly Revealed by Multidimensional Electronic-Vibrational Spectroscopy
Authors: Gaynor James D. , Khalil Munira
Published: January 2021

This dissertation demonstrates multidimensional Electronic-Vibrational spectroscopy as a direct probe of ultrafast vibronic phenomena in photoexcited molecules. These experimental and theoretical advancements reveal new insights into nature’s fastest reactions: electron transfer and proton transfer.
Carotenoid-Mediated Light Harvesting in Plants Uncovered with Ultrabroadband Two-Dimensional Electronic Spectroscopy
Authors: Son Minjung , Pinnola Alberta , Bassi Roberto , Schlau-Cohen Gabriela S.
Published: January 2021

We demonstrate an ultrabroadband two-dimensional electronic spectrometer that maps energy flow across the visible range. This apparatus enables observation of previously unexplored carotenoid-mediated light-harvesting dynamics in plants, including identification of a debated carotenoid dark state.
Generation of staircase pulses in fiber lasers
Authors: Semaan G. , Komarov A. , Kemel M. , Nady A. , Salhi M. , Sanchez F.
Published: January 2021

We report the generation of staircase pulses in a passively mode-locked fiber laser. The optical filtering shows that the staircase pulses consist of two distinct square pulses associated to different wavelengths.
Pulse compression in Nonlinear optical loop mirror through self-similar propagation
Authors: Lidiya A. Esther , Raja R. Vasantha Jayakantha , Husakou Anton
Published: January 2021

Numerical demonstration of nonlinear pulse compression mechanism has proposed to obtain few cycle low pedestal femtosecond pulses at 800 nm using self-similarly designed photonic crystal fiber in the nonlinear optical loop mirror configuration
Numerical Modelling of Stretched Pulse Hybrid Mode-locked Tm-doped All-fiber Laser at 1.9 µm Compared with Experimental Data
Authors: Voropaev V.S. , Donodin A.I. , Voronets A.I. , Batov D.T. , Vlasov D.S. , Tarabrin M.K. , Lazarev V.A. , Likhachev M.E. , Salganskii M.Yu. , Yashkov M.V. , Karasik V.E.
Published: January 2021

The results of numerical simulations of the 300 fs stretched pulse generation in a hybrid mode-locked Tm-doped all-fibre laser are presented. The intracavity pulse dynamics is an-alyzed. The uncertainty relative experimental data are discussed.
Dual-Comb Microscopy
Authors: Yasui Takeshi
Published: January 2021

Two-dimensional image pixels of a sample are encoded onto optical frequency comb modes via spectral encoding, and the resulting mode-resolved amplitude and phase spectra are used to decode full-field confocal and phase images without scanning.
Electro-optic combs generated via direct digital synthesis for spectroscopy and physical metrology
Authors: Long David A. , Reschovsky Benjamin J. , Zhou Feng , Bao Yiliang , Madugani Ramgopal , Allen Richard A. , Gorman Jason J. , LeBrun Thomas W.
Published: January 2021

Electro-optic frequency combs were generated via chip-based direct digital synthesis and utilized to interrogate cavity optomechanical sensors. This approach offers a combination of high dynamic range, frequency agility, sensitivity, and accuracy.
Detecting rotational vacuum friction by optically levitated nanorotor
Authors: Xu Zhujing , Li Tongcang
Published: January 2021

We propose to measure rotational vacuum friction between an optically levitated nanosphere and a nearby surface. We show the feasibility by analyzing the calculated vacuum friction torque with the air damping and the sensitivity.
Coupled dynamics of an optically levitated nanodumbbell
Authors: Ju Peng , Bang Jaehoon , Seberson Troy , Ahn Jonghoon , Xu Zhujing , Gao Xingyu , Robicheaux Francis , Li Tongcang
Published: January 2021

We observe the coupled dynamics of both translational motion and torsional vibration for a levitated nanodumbbell at high vacuum. We also report cooling multiple degrees of freedom of the levitated nanodumbbell.
Macroscopic Entanglement Between YIG Samples Without Using Intrinsic Nonlinearities
Authors: Nair Jayakrishnan M. P. , Agarwal Girish S.
Published: January 2021

We present a novel scheme to generate an entangled pair of yttrium iron garnet (YIG) samples in a cavity system which does not involve any nonlinearities. The generated macroscopic entanglement can survive up to 500mK.
Spectral Broadening with Two-Color-Field in a Molecular Gas-Filled Hollow-Core Fiber
Authors: Truong Tran-Chau , Beetar John E. , Chini Michael
Published: January 2021

An ultrabroadband optical spectrum, covering a wavelength range of <500 nm to beyond 1600 nm, is generated by nonlinear propagation of a two-color field from a Yb:KWG laser amplifier in N2O-filled hollow-core fiber.
Nonlinear Post-Compression of Mid-IR Pulses Using Multi-Pass Cells
Authors: Carlson Daniel R. , Morrill Drew W. , Murnane Margaret M. , Kapteyn Henry C. , Hemmer Michaël
Published: January 2021

We report numerical simulations showing self-compression of mid-IR pulses in a multi-pass cell. Balancing of self-phase modulation and material dispersion yields few-cycle pulses for λ0 = 1.8, 3 and 6 μm wavelengths while mitigating self-focusing.
Characterization of an Isolated Attosecond Pulse by Using Carrier-Envelope-Phase Dependence
Authors: Ko Dong Hyuk , Brown Graham G. , Zhang Chunmei , Corkum Paul B.
Published: January 2021

We propose a new method to measure an isolated attosecond pulse by employing its carrier-envelope-phase dependence to a driving laser pulse. Our method is simple and robust since it does not require a secondary pulse.
Angular Dependence of Laser-Induced Electron Rescattering in Molecules
Authors: Hu Hongtao , Kangaparambi Sarayoo , Dorner-Kirchner Martin , Hanus Václav , Baltuška Andrius , Kitzler-Zeiler Markus , Xie Xinhua
Published: January 2021

We report on the retrieval of the angular dependence of laser-induced electron rescattering in CO2 with a novel method from the measured rotational half revival signals of filed-free aligned molecules using a reaction microscope.
Beef cattle feedlot emissions measured using open-path dual-comb spectroscopy
Authors: Hutcherson Lindsay C. , Herman Daniel I. , Weerasekara Chinthaka , Giorgetta Fabrizio R. , Cossel Kevin C. , Waxman Eleanor M. , Colacion Gabriel M. , Newbury Nathan R. , Welch Stephen M. , DePaola Brett D. , Coddington Ian , Santos Eduardo A. , Washburn Brian R.
Published: January 2021

A dual comb-spectroscopy system was implemented in a beef cattle feedlot alongside a commercial cavity ring down system in order to measure concentrations of relative agricultural gases and compare flux emission rates.
Frequency Comb Spectroscopy: Stop or Go?
Authors: Picqué Nathalie
Published: January 2021

Frequency combs have revolutionized time and frequency metrology. Their application to spectroscopy over broad spectral bandwidths attracts an ever-increasing number of scientists for its intriguing potential for high accuracy, resolution and recording speed.
Mixing-time evolution of coherent exciton-polariton response due to many-body interactions
Authors: Paul Jagannath , Wahlstrand Jared K. , Bristow Alan D.
Published: January 2021

Multidimensional coherent spectra are presented for exciton-polaritons in a semiconductor microcavity at cryogenic temperatures as a function of mixing time. A decrease in vacuum Rabi splitting is observed along with spectral phase shifts.
Unusually long carrier lifetime in a Mott insulator revealed by time-resolved Photoemission Electron Microscopy
Authors: Babich Danylo , Fukumoto Keiki , Corraze Benoit , Tranchant Julien , Lorenc Maciej , Cailleau Hervé , Koshihara S-Y , Cario Laurent , Janod Etienne
Published: January 2021

Mott insulators display puzzling insulator to metal transitions under electric field. We study here the Mott insulator GaV4S8 using time-resolved Photoemission Electron Microcopy and reveal unusually long carrier lifetimes, supporting the mechanism of electronic avalanche.
Few-cycle pulses of laser-driven intra-band electron oscillations and measurement of carrier-envelope phase
Authors: Gruzdev Vitaly , Sergaeva Olga
Published: January 2021

Analytical model of intra-band electron oscillations driven by intense few-cycle laser pulses perfectly fits experimental data on ultrafast conversion of light to bias-free electric current and suggests a new method to measure carrier-envelope phase.
High Harmonic Generation from Thin Film LiNbO3
Authors: Journigan Troie , Gholam-Mirzaei Shima , Crites Erin , Turkowski Volodymyr , Sjaardema Tracy , Fathpour Sasan , Chini Michael
Published: January 2021

We study high harmonics generation from LiNbO3 films driven by femtosecond mid-infrared laser pulses. By applying an electric field, we examine changes in ferroelectric crystal symmetry influencing harmonics spectra.
Probing Structural Dynamics in 2D Lead Iodide Perovskites Using Raman Spectroscopy
Authors: Sanni Adedayo M. , Lavan Sydney N. , Rury Aaron S.
Published: January 2021

Low dimension hybrid perovskites are important class of materials for next generation lighting technologies. We use vibrational Raman spectroscopy to probe the structures of 3 analogues of these hybrid perovskites central to their lighting applications.
Attosecond Science at X-ray Free Electron Lasers
Authors: Li Siqi , Driver Taran , Duris Joseph , Champenois Elio , O’Neal Jordan , Marinelli Agostino , Cryan James P.
Published: January 2021

This work will discuss the potential of using x-ray free electron lasers (XFELs) for applications in attosecond science. We detail the production, characterization, and use of soft X-ray attosecond pulses at the Linac Coherent Light Source.
Imprinting Laser-Particle Micro-correlations to enhance X-ray Free Electron Laser Performance
Authors: Carbajo Sergio , Tang Jingyi , Lemons Randy , Liu Wei , Vetter Sharon , Maxwell Timothy , Decker Franz-Josef , Lutman Alberto , Marcus Gabriel , Moeller Stefan , Huang Zhirong , Ratner Daniel
Published: January 2021

we will review recent advances exploiting laser-particle interactions to enhance the performance of accelerators and X-ray free electron lasers and their applications in ultrafast science.
Monitoring Ultrafast Photoisomerization of Azobenzene by Time-Resolved X-Ray Diffraction
Authors: Keefer Daniel , Aleotti Flavia , Rouxel Jérémy , Segatta Francesco , Gu Bing , Nenov Artur , Garavelli Marco , Mukamel Shaul
Published: January 2021

Time-resolved X-Ray diffraction signals are simulated to monitor the ultrafast photoisomerization of azobenzene, a textbook photophysical process. Different signal contributions, with a special focus on scattering from coherences emerging at the conical intersection, are discussed.
Precision measurement of the quantum vacuum with petawatt-class lasers
Authors: Hill W. T. , Roso L. , Fedosejevs R. , He C. , Longman A. , Aginako J. I. A. , Pérez-Hernández J. A.
Published: January 2021

The prospects - what can be learned, what conditions are required and what tools are needed - for precision measurements of the quantum vacuum at intensities of 10
25
W/cm
2
and above will be discussed.
Optical Parametric Chirped Pulse Amplification at Critical Wavelength Degeneracy - a proposed solution for 100-PW Femtosecond Lasers Development
Authors: Dabu Razvan
Published: January 2021

At signal critical wavelength, super-broad gain bandwidths can be obtained in crystals pumped at degeneracy. Partially deuterated KDP crystals, pumped by green lasers, can amplify ~1.1-μm central wavelength, sub-10 fs laser pulses, at kJ-energy level.
Prospects for Ultra High Irradiance at Extreme Light Infrastructure - Nuclear Physics
Authors: Dancus Ioan , Lureau François , Matras Guillaume , Chalus Olivier , Derycke Christophe , Morbieu Thomas , Radier Christophe , Casagrande Olivier , Laux Sébastien , Ricaud Sandrine , Rey Gilles , Pellegrina Alain , Richard Caroline , Boudjemaa Laurent , Boisson Christophe Simon , Baleanu Andrei , Banici Romeo , Gradinariu Andrei , Caldararu Constantin , De Boisdeffre Bertrand , Ghenuche Petru , Naziru Andrei , Kolliopoulos Georgios , Neagu Liviu , Dabu Razvan , Ursescu Daniel
Published: January 2021

The demonstration of the first 10 PW pulses during March 2019 the High Power Laser System at ELI-NP together with extensive tests, provides now the possibility to evaluate the ultrahigh irradiance in reach.
Complete, Single Shot, Spatiotemporal Measurement of a Terawatt Laser System
Authors: Grace Elizabeth , Ma Tammy , Guang Zhe , Jafari Rana , Park Jaebum , Clark Jerry , Kemp Elijah , Moody Jim , Rhodes Michelle , Shepherd Ronnie , Ping Yuan , Stuart Brent , Trebino Rick
Published: January 2021

A single shot, complete spatiotemporal measurement of the complex electric field E(x,y,z,t) emitted by a high power (>0.1 TW) laser is demonstrated for the first time. Color movies of the laser's electric field are retrieved, and the temporal, spectral, and spatial field features are examined.
Ultrashort Pulse Amplification and Compression at 1.9 μm Using Normal Dispersion Thulium-Doped Germanosilicate Fiber
Authors: Voropaev V.S. , Donodin A.I. , Voronets A.I. , Batov D.T. , Vlasov D.S. , Tarabrin M.K. , Lazarev V.A. , Khegai A.M. , Likhachev M.E. , Yashkov M.V. , Karasik V.E.
Published: January 2021

We demonstrate amplification dynamics and compression of 1.9 μm ultrashort (330 fs) pulses using a normal dispersion thulium-doped germanosilicate fiber. The maximum pulse energy is 65 nJ and minimum pulse duration is 60 fs.
InP high power monolithically integrated widely tunable laser and SOA array for hybrid integration
Authors: McKinzie Keith A. , Wang Cong , Noman Abdullah Al , Mathine David L. , Han Kyunghun , Leaird Daniel E. , Hoefler Gloria E. , Lal Vikrant , Kish Fred , Qi Minghao , Weiner Andrew M.
Published: January 2021

We present a monolithic InP-based photonic integrated circuit (PIC) consisting of a widely tunable laser master oscillator feeding an array of integrated semiconductor optical amplifiers that are interferometrically combined on-chip in a single-mode waveguide. We demonstrate a stable and efficient on-chip coherent beam combination and obtain up to 240 mW average power from the monolithic PIC, with 30–50 kHz Schawlow-Townes linewidths and >180 mW average power across the extended C-band. We also explored hybrid integration of the InP-based laser and amplifier array PIC with a high quality factor silicon nitride microring resonator. We observe lasing based on gain from the interferometrically combined amplifier array in an external cavity formed via feedback from the silicon nitride microresonator chip; this configuration results in narrowing of the Schawlow-Townes linewidth to ∼3 kHz with 37.9 mW average power at the SiN output facet. This work demonstrates a new approach toward high power, narrow linewidth sources that can be integrated with on-chip single-mode waveguide platforms for potential applications in nonlinear integrated photonics.
3D reconstruction of weakly scattering objects from 2D intensity-only measurements using the Wolf transform
Authors: Ayoub Ahmed B. , Lim Joowon , Antoine Elizabeth E. , Psaltis Demetri
Published: January 2021

A new approach to optical diffraction tomography (ODT) based on intensity measurements is presented. By applying the Wolf transform directly to intensity measurements, we observed unexpected behavior in the 3D reconstruction of the sample. Such a reconstruction does not explicitly represent a quantitative measure of the refractive index of the sample; however, it contains interesting qualitative information. This 3D reconstruction exhibits edge enhancement and contrast enhancement for nanostructures compared with the conventional 3D refractive index reconstruction and thus could be used to localize nanoparticles such as lipids inside a biological sample.
An extended lidar-based cirrus cloud retrieval scheme: first application over an Arctic site
Authors: Nakoudi Konstantina , Stachlewska Iwona S. , Ritter Christoph
Published: January 2021

Accurate and precise characterization of cirrus cloud geometrical and optical properties is essential for better constraining their radiative footprint. A lidar-based retrieval scheme is proposed here, with its performance assessed on fine spatio-temporal observations over the Arctic site of Ny-Ålesund, Svalbard. Two contributions related to cirrus geometrical (dynamic Wavelet Covariance Transform (WCT)) and optical properties (constrained Klett) are reported. The dynamic WCT rendered cirrus detection more robust, especially for thin cirrus layers that frequently remained undetected by the classical WCT method. Regarding optical characterization, we developed an iterative scheme for determining the cirrus lidar ratio (LR
ci
) that is a crucial parameter for aerosol - cloud discrimination. Building upon the Klett-Fernald method, the LR
ci
was constrained by an additional reference value. In established methods, such as the double-ended Klett, an aerosol-free reference value is applied. In the proposed constrained Klett, however, the reference value was approximated from cloud-free or low cloud optical depth (COD up to 0.2) profiles and proved to agree with independent Raman estimates. For optically thin cirrus, the constrained Klett inherent uncertainties reached 50% (60-74%) in terms of COD (LR
ci
). However, for opaque cirrus COD (LR
ci
) uncertainties were lower than 10% (15%). The detection method discrepancies (dynamic versus static WCT) had a higher impact on the optical properties of low COD layers (up to 90%) compared to optically thicker ones (less than 10%). The constrained Klett presented high agreement with two established retrievals. For an exemplary cirrus cloud, the constrained Klett estimated the COD355 (

L

R

c
i

355

) at 0.28 ± 0.17 (29 ± 4 sr), the double-ended Klett at 0.27 ± 0.15 (32 ± 4 sr) and the Raman retrievals at 0.22 ± 0.12 (26 ± 11 sr). Our approach to determine the necessary reference value can also be applied in established methods and increase their accuracy. In contrast, the classical aerosol-free assumption led to 44  sr LR
ci
overestimation in optically thin layers and 2-8 sr in thicker ones. The multiple scattering effect was corrected using Eloranta (1998) and accounted for 50-60% extinction underestimation near the cloud base and 20-30% within the cirrus layers.
High spatial and energy resolution electron energy loss spectroscopy of the magnetic and electric excitations in plasmonic nanorod oligomers
Authors: Pakeltis Grace , Rotunno Enzo , Khorassani Siamak , Garfinkel David A. , Collette Robyn , West Claire A. , Retterer Scott T. , Idrobo Juan Carlos , Masiello David J. , Rack Philip D.
Published: January 2021

We leverage the high spatial and energy resolution of monochromated aberration-corrected scanning transmission electron microscopy to study the hybridization of cyclic assemblies of plasmonic gold nanorods. Detailed experiments and simulations elucidate the hybridization of the coupled long-axis dipole modes into collective magnetic and electric dipole plasmon resonances. We resolve the magnetic dipole mode in these closed loop oligomers with electron energy loss spectroscopy and confirm the mode assignment with its characteristic spectrum image. The energy splitting of the magnetic mode and antibonding modes increases with the number of polygon edges (n). For the n=3-6 oligomers studied, optical simulations using normal incidence and s-polarized oblique incidence show the respective electric and magnetic modes’ extinction efficiencies are maximized in the n=4 arrangement.
Fabrication of high-precision freeform surface on die steel by ultrasonic-assisted slow tool servo
Authors: Xing Yintian , Li Chuang , Liu Yue , Yang Chao , Xue Changxi
Published: January 2021

The mold core fabrication of a freeform surface on die steel by ultra-precision machining can make the optical elements of freeform be mass-produced by plastic injection and glass mold pressing. However, because steel is a typical difficult-to-cut material, the technical limitations of existing machining methods hardly meet the current requirements of design. In this paper, a novel machining method, one-dimension ultrasonic-assisted slow tool servo (UASTS) turning, is proposed to manufacture the freeform surface with high-precision and large-steepness on the die steel. Aiming at the characteristics of UASTS turning, the tool trajectory is generated by analyzing the compensation of tool radius and confirming the position of ultrasonic displacement. The 2D surface model contours of residual tool marks are established for predicting the 3D surface topography based on considering the effects of kinematics, material elastic recovery and plastic side flow. In the experiments, the large-amplitude bidirectional sinusoidal wave grid (BSWG) surface is successfully fabricated by UASTS technology on the material, Polmax steel, for which the value Rt of surface roughness is less than 70nm and the value Ra of surface roughness can achieve to 3.298nm. The results show that the freeform surface with high-precision and large-steepness can be machined by UASTS turning technology on mold steel.
Anisotropic second-harmonic generation from monocrystalline gold flakes
Authors: Boroviks Sergejs , Yezekyan Torgom , Rodríguez Echarri Álvaro , García de Abajo F. Javier , Cox Joel D. , Bozhevolnyi Sergey I. , Mortensen N. Asger , Wolff Christian
Published: January 2021

Noble metals with well-defined crystallographic orientation constitute an appealing class of materials for controlling light–matter interactions on the nanoscale. Nonlinear optical processes, being particularly sensitive to anisotropy, are a natural and versatile probe of crystallinity in nano-optical devices. Here we study the nonlinear optical response of monocrystalline gold flakes, revealing a polarization dependence in second-harmonic generation from the {111} surface that is markedly absent in polycrystalline films. Our findings confirm that second-harmonic microscopy is a robust and non-destructive method for probing the crystallographic orientation of gold, and can serve as a guideline for enhancing nonlinear response in plasmonic systems.
µJ-level multi-cycle terahertz generation in a periodically poled Rb:KTP crystal
Authors: Tian Wenlong , Cirmi Giovanni , Olgun Halil T. , Mutter Patrick , Canalias Carlota , Zukauskas Andrius , Wang Lu , Kueny Elias , Ahr Frederike , Calendron Anne-Laure , Reichert Fabian , Hasse Kore , Hua Yi , Schimpf Damian N. , Çankaya Hüseyin , Pergament Mikhail , Hemmer Michael , Matlis Nicholas , Pasiskevicius Valdas , Laurell Fredrik , Kärtner Franz X.
Published: January 2021

We demonstrate multi-cycle terahertz (MC-THz) generation in a 15.5 mm long periodically poled rubidium (Rb)-doped potassium titanyl phosphate (Rb:PPKTP) crystal with a poling period of 300 µm. By cryogenically cooling the crystal to 77 K, up to 0.72 µJ terahertz energy is obtained at a frequency of 0.5 THz with a 3 GHz bandwidth. A maximum internal optical-to-terahertz conversion efficiency of 0.16% is achieved, which is comparable with results achieved using periodically poled lithium niobate crystal. Neither photorefractive effects nor damage was observed with up to

900

m
J

/

c
m

2

, showing the great potential of Rb:PPKTP for multi-millijoule-level MC-THz generation.
Variable immersion microscopy with a high numerical aperture
Authors: Ishida Keita , Naruse Kanta , Mizouchi Yuta , Ogawa Yoshihiro , Matsushita Michio , Shimi Takeshi , Kimura Hiroshi , Fujiyoshi Satoru
Published: January 2021

Three-dimensional (3D) optical microscopy with a high numerical aperture (NA) remains challenging for thick biological specimens owing to aberrations arising from interface refractions. We developed a variable immersion lens (VIL) to passively minimize these aberrations. A VIL is a high-NA concentric meniscus lens and was used in combination with an aberration-corrected high-NA reflecting objective (TORA-FUJI mirror). Wave-optics simulation at a wavelength of 488 nm showed that a VIL microscope enables diffraction-limited 1.2-NA imaging in water (refractive index of 1.34) at a depth of 0.3 mm by minimizing aberrations due to refraction of a sample interface. Another aberration due to the refractive index mismatching between a mounting medium, and an object can also be corrected by the VIL system, because various fluids with different refractive indices can be used as mounting media for the VIL. As a result of correcting the two aberrations at the same time, we experimentally demonstrated that a 6 µm diameter fluorescent bead can be imaged to the true dimensions in 3D.
Predicting evolutionary change at the DNA level in a natural Mimulus population
Authors: Monnahan Patrick J. , Colicchio Jack , Fishman Lila , Macdonald Stuart J. , Kelly John K.
Published: January 2021

Evolution by natural selection occurs when the frequencies of genetic variants change because individuals differ in Darwinian fitness components such as survival or reproductive success. Differential fitness has been demonstrated in field studies of many organisms, but it remains unclear how well we can quantitatively predict allele frequency changes from fitness measurements. Here, we characterize natural selection on millions of Single Nucleotide Polymorphisms (SNPs) across the genome of the annual plantMimulus guttatus. We use fitness estimates to calibrate population genetic models that effectively predict allele frequency changes into the next generation. Hundreds of SNPs experienced “male selection” in 2013 with one allele at each SNP elevated in frequency among successful male gametes relative to the entire population of adults. In the following generation, allele frequencies at these SNPs consistently shifted in the predicted direction. A second year of study revealed that SNPs had effects on both viability and reproductive success with pervasive trade-offs between fitness components. SNPs favored by male selection were, on average, detrimental to survival. These trade-offs (antagonistic pleiotropy and temporal fluctuations in fitness) may be essential to the long-term maintenance of alleles. Despite the challenges of measuring selection in the wild, the strong correlation between predicted and observed allele frequency changes suggests that population genetic models have a much greater role to play in forward-time prediction of evolutionary change.
Understanding drivers of family planning in rural northern India: An integrated mixed-methods approach
Authors: Jain Mokshada , Caplan Yael , Ramesh B. M. , Isac Shajy , Anand Preeti , Engl Elisabeth , Halli Shiva , Kemp Hannah , Blanchard James , Gothalwal Vikas , Namasivayam Vasanthakumar , Kumar Pankaj , Sgaier Sema K.
Published: January 2021

Background

Family planning is a key means to achieving many of the Sustainable Development Goals. Around the world, governments and partners have prioritized investments to increase access to and uptake of family planning methods. In Uttar Pradesh, India, the government and its partners have made significant efforts to increase awareness, supply, and access to modern contraceptives. Despite progress, uptake remains stubbornly low. This calls for systematic research into understanding the ‘why’—why people are or aren’t using modern methods, what drives their decisions, and who influences them.

Methods

We use a mixed-methods approach, analyzing three existing quantitative data sets to identify trends and geographic variation, gaps and contextual factors associated with family planning uptake and collecting new qualitative data through in-depth immersion interviews, journey mapping, and decision games to understand systemic and individual-level barriers to family planning use, household decision making patterns and community level barriers.

Results

We find that reasons for adoption of family planning are complex–while access and awareness are critical, they are not sufficient for increasing uptake of modern methods. Although awareness is necessary for uptake, we found a steep drop-off (59%) between high awareness of modern contraceptive methods and its intention to use, and an additional but smaller drop-off from intention to actual use (9%). While perceived access, age, education and other demographic variables partially predict modern contraceptive intention to use, the qualitative data shows that other behavioral drivers including household decision making dynamics, shame to obtain modern contraceptives, and high-risk perception around side-effects also contribute to low intention to use modern contraceptives. The data also reveals that strong norms and financial considerations by couples are the driving force behind the decision to use and when to use family planning methods.

Conclusion

The finding stresses the need to shift focus towards building intention, in addition to ensuring access of trained staff, and commodities drugs and equipment, and building capacities of health care providers.
Tracking R of COVID-19: A new real-time estimation using the Kalman filter
Authors: Arroyo-Marioli Francisco , Bullano Francisco , Kucinskas Simas , Rondón-Moreno Carlos
Published: January 2021

We develop a new method for estimating the effective reproduction number of an infectious disease (R) and apply it to track the dynamics of COVID-19. The method is based on the fact that in the SIR model, R is linearly related to the growth rate of the number of infected individuals. This time-varying growth rate is estimated using the Kalman filter from data on new cases. The method is easy to implement in standard statistical software, and it performs well even when the number of infected individuals is imperfectly measured, or the infection does not follow the SIR model. Our estimates of R for COVID-19 for 124 countries across the world are provided in an interactive online dashboard, and they are used to assess the effectiveness of non-pharmaceutical interventions in a sample of 14 European countries.
Steccherinum tenuissimum and S. xanthum spp. nov. (Polyporales, Basidiomycota): New species from China
Authors: Wu Ya-Xing , Wu Jian-Rong , Zhao Chang-Lin
Published: January 2021

Two new wood-inhabiting fungal species, Steccherinum tenuissimum and S. xanthum spp. nov. are described based on a combination of morphological features and molecular evidence. Steccherinum tenuissimum is characterized by an annual growth habit, resupinate basidiomata with an odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae, strongly encrusted cystidia and basidiospores measuring 3–5 × 2–3.5 μm. Steccherinum xanthum is characterized by odontioid basidiomata and a monomitic hyphal system with generative hyphae bearing clamp connections and covering by crystals, colourless, thin-walled, smooth, IKI–, CB–and has basidiospores measuring 2.7–5.5 × 1.8–4.0 μm. Sequences of the ITS and nLSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and Bayesian inference methods. The phylogenetic analyses based on molecular data of ITS + nLSU sequences showed that two new Steccherinum species felled into the residual polyporoid clade. Further investigation was obtained for more representative taxa in Steccherinum based on ITS + nLSU sequences, which demonstrated that S. tenuissimum and S. xanthum were sister to S. robustius with high support (100% BP, 100% BS and 1.00 BPP).
Why are song lyrics becoming simpler? a time series analysis of lyrical complexity in six decades of American popular music
Authors: Varnum Michael E. W. , Krems Jaimie Arona , Morris Colin , Wormley Alexandra , Grossmann Igor
Published: January 2021

Song lyrics are rich in meaning. In recent years, the lyrical content of popular songs has been used as an index of culture’s shifting norms, affect, and values. One particular, newly uncovered, trend is that lyrics of popular songs have become increasingly simple over time. Why might this be? Here, we test the idea that increasing lyrical simplicity is accompanied by a widening array of novel song choices. We do so by using six decades (1958–2016) of popular music in the United States (N = 14,661 songs), controlling for multiple well-studied ecological and cultural factors plausibly linked to shifts in lyrical simplicity (e.g., resource availability, pathogen prevalence, rising individualism). In years when more novel song choices were produced, the average lyrical simplicity of the songs entering U.S. billboard charts was greater. This cross-temporal relationship was robust when controlling for a range of cultural and ecological factors and employing multiverse analyses to control for potentially confounding influence of temporal autocorrelation. Finally, simpler songs entering the charts were more successful, reaching higher chart positions, especially in years when more novel songs were produced. The present results suggest that cultural transmission depends on the amount of novel choices in the information landscape.
Emergency department visits among patients transported by law enforcement officers
Authors: Rosen David L. , Travers Debbie
Published: January 2021

Law enforcement officers frequently encounter people with health conditions. We sought to estimate the rates, diagnoses, and characteristics of emergency department (ED) visits among patients transported directly by law enforcement. We analyzed statewide North Carolina Emergency Department data for adults, aged 18+ years, from 2009 to 2016. We estimated transport rates using census data; categorized primary ED diagnoses into 13 major and 8 substituent categories; compared county transport rates by rurality; and examined patient characteristics. There were 136,240 patients transported by law enforcement; annual rates increased from 186.9 (per 100,000 adult residents) in 2009 to 279.2 in 2016. Among visits, 67.7% were among men, the median age was 37 years, and 20.4% resulted in a hospital admission. Most common primary diagnoses were Mental Health Diagnoses (43.1%)—including Schizophrenia and other Psychotic Disorders (7.6%), Mood Disorders (9.7%), and Alcohol and Substance Use (10.7%)—followed by Injury and Poisoning (12.4%) and Circulatory conditions (4.1%). Involuntary commitments constituted 22% of all visits. The median transport rate in rural counties, 291.1, was 2 times that of large metro counties, 145.1. The visit rate increased by nearly 50% during the study period, with the highest rates in rural counties. Many transports were for Mental Illness and involuntary commitments. The relatively common occurrence of law enforcement transports suggests the need for greater research to understand factors influencing law enforcement transport decisions, the impact of these transports on patient health and safety, and the repercussions on patient care of a growing officer presence in EDs.
The MITF paralog tfec is required in neural crest development for fate specification of the iridophore lineage from a multipotent pigment cell progenitor
Authors: Petratou Kleio , Spencer Samantha A. , Kelsh Robert N. , Lister James A.
Published: January 2021

Understanding how fate specification of distinct cell-types from multipotent progenitors occurs is a fundamental question in embryology. Neural crest stem cells (NCSCs) generate extraordinarily diverse derivatives, including multiple neural, skeletogenic and pigment cell fates. Key transcription factors and extracellular signals specifying NCSC lineages remain to be identified, and we have only a little idea of how and when they function together to control fate. Zebrafish have three neural crest-derived pigment cell types, black melanocytes, light-reflecting iridophores and yellow xanthophores, which offer a powerful model for studying the molecular and cellular mechanisms of fate segregation. Mitfa has been identified as the master regulator of melanocyte fate. Here, we show that an Mitf-related transcription factor, Tfec, functions as master regulator of the iridophore fate. Surprisingly, our phenotypic analysis oftfecmutants demonstrates that Tfec also functions in the initial specification of all three pigment cell-types, although the melanocyte and xanthophore lineages recover later. We show that Mitfa repressestfecexpression, revealing a likely mechanism contributing to the decision between melanocyte and iridophore fate. Our data are consistent with the long-standing proposal of a tripotent progenitor restricted to pigment cell fates. Moreover, we investigate activation, maintenance and function oftfecin multipotent NCSCs, demonstrating for the first time its role in the gene regulatory network forming and maintaining early neural crest cells. In summary, we build on our previous work to characterise the gene regulatory network governing iridophore development, establishing Tfec as the master regulator driving iridophore specification from multipotent progenitors, while shedding light on possible cellular mechanisms of progressive fate restriction.
Exploring meat processing in the past: Insights from the Nunamiut people
Authors: Soulier Marie-Cécile
Published: January 2021

Improving our knowledge of subsistence strategies and food processing techniques of past societies is of prime interest for better understanding human cultures as well as multiple aspects of human evolution. Beyond the simple matter of food itself, a substantial portion of socio-economic behavior is expressed in what, how, when, and with whom we eat. Over the last few decades, diverse methodologies for the analysis and interpretation of cut marks have progressively provided new insights for past butchery practices. For example, a recent study of the production of antelope biltong in South Africa concluded that the drying of meat generates high frequencies of longitudinal cut marks. This paper presents a cut mark analysis of faunal remains recovered by Lewis Binford from 8 campsites occupied by Nunamiut groups from the end of 19thto middle of the 20thcentury in the area around Anaktuvuk Pass, Alaska. The preparation of meat—primarily from caribou (Rangifer tarandus)–varied at these sites according to the season of occupation and was, depending on the site, either immediately consumed, processed after being stored in ice-cellars, or dried and stored. These faunal assemblages therefore provide a unique opportunity to explore the material traces of different meat preparation and preservation techniques in order to identify whether specific patterns can be identified and subsequently used to explore subsistence practices in the past. Binford’s Nunamiut faunal assemblages, which were produced by individuals using traditional techniques and methods, were analyzed in order to 1) further test the hypothesis that meat drying produces high frequencies of longitudinal cut marks, 2) explore the common assumption that skilled butchers leave smaller numbers of cut marks on bones compared to less experienced individuals, and 3) test whether cut mark patterns vary as a function of the processing techniques employed. The introduction of a %cutL index represents a quicker alternative to geo-referencing cut marks on bones when exploring meat processing techniques and methods and can easily be integrated in zooarchaeological analyses. While the results obtained support processing techniques linked to meat drying to leave high numbers of longitudinal cut marks, they are inconsistent with cut mark frequencies varying as a function of the butcher’s skill and experience. Analyzing cut mark patterns is therefore a reliable means for exploring food processing by past human societies and, by extension, their methods for safeguarding against unfavorable seasonal variations in both the abundance and condition of prey species. Identifying food storage in the archaeological record equally provides a unique window on to the social dynamics and potential inequalities of past societies.
COVID-19: Short-term forecast of ICU beds in times of crisis
Authors: Goic Marcel , Bozanic-Leal Mirko S. , Badal Magdalena , Basso Leonardo J.
Published: January 2021

By early May 2020, the number of new COVID-19 infections started to increase rapidly in Chile, threatening the ability of health services to accommodate all incoming cases. Suddenly, ICU capacity planning became a first-order concern, and the health authorities were in urgent need of tools to estimate the demand for urgent care associated with the pandemic. In this article, we describe the approach we followed to provide such demand forecasts, and we show how the use of analytics can provide relevant support for decision making, even with incomplete data and without enough time to fully explore the numerical properties of all available forecasting methods. The solution combines autoregressive, machine learning and epidemiological models to provide a short-term forecast of ICU utilization at the regional level. These forecasts were made publicly available and were actively used to support capacity planning. Our predictions achieved average forecasting errors of 4% and 9% for one- and two-week horizons, respectively, outperforming several other competing forecasting models.
G1 point mutation in growth differentiation factor 9 gene affects litter size in Sudanese desert sheep
Authors: Abdelgadir Amani Z. , Musa Lutfi M. A. , Jawasreh Khaleel I. , Saleem Aubai. O. , El-Hag Faisal , Ahmed Mohamed-Khair A.
Published: January 2021

Background and Aim: Sudanese desert sheep encompass different sheep breeds named according to the different Sudanese tribes that rear them such as the Dubasi, Shugor, and Watish sheep. The objectives of this study were to screen for G1 point mutation in the polymorphic growth differentiation factor 9 (GDF9) gene, investigate its association with litter size, and construct the phylogeny of the different tribal breeds that belong to the Sudanese Desert sheep tribal types.

Materials and Methods: Genomic DNA was extracted from whole blood of three tribal Desert sheep breeds (Dubasi, Watish, and Shugor) using the guanidine chloride method. Polymerase chain reaction-restriction fragment length polymorphism with HhaI restriction enzyme and sequencing techniques was used for genotyping the GDF9 locus for possible mutations associated with litter size in the three desert sheep tribal types.

Results: G1 mutation in GDF9 caused the replacement of Arginine by Histidine at residue 87. The wild type allele (A) had the highest frequency, whereas the mutant type allele (a) had the lowest in all the sequenced subtypes. The genotype frequencies of the wild type ewes (AA) were higher than the heterozygous (Aa) and the mutant type (aa) frequencies in the three studied desert sheep types. No significant differences were found in the allele frequency between the three tribal types. Litter size was significantly influenced by the genotypes of GDF9 gene, parities, and subtypes (p≤0.01, 0.01, and 0.05, respectively). In the Watish sheep type, heterozygous sheep in their second parity recorded the highest litter size. Sequence alignment of GDF9 gene samples with the database entry indicated that all three tribal types were similar and identical to the reference sequence. The phylogenetic tree revealed that Shugor is the common ancestor of the studied types and Watish is more closely related to Shugor than Dubasi. This result mi ght partly explain the lower reproductive performance of Dubasi compared to Watish and Shugor.

Conclusion: The presence of one copy of GDF9 gene increased litter size in the studied Sudanese Desert sheep. This locus may be used as a biomarker for litter size improvement through genotypic selection and allele or gene introgression.
Socio-economic Transformations in the Regional Spatial Development of the PRC during the Period from the Late 1970s to the Early 1990s
Authors: Makeeva S.B.
Published: January 2021

The paper examines the historical features of structural socio-economic transformations in the regional spatial development of the PRC during the implementation of the policy of reforms and opening up. The analysis is based on the conclusions of Li Jingwen, a Chinese scientist, specialist in the field of China's regional economy in the second half of the 20th century. In the context of structural socio-economic transformations in the regional spatial development of the PRC in the period from the late of 1970 to the early 1990s in order to get rid of the disproportionate industrial location and uneven distribution of resources, promote the economic development of the central and western regions and implement the coordinated development of the regional economy, the Chinese government aimed to promote the strategy of economic development of less developed regions at the right time, while changing the vector of development of the regional economy from the past strategies of coastal and border economic development to the strategy of economic balanced development of the entire regional space of the PRC.
Fifty shades of innovation – from open toward user, and open collaborative forms of innovation – an overview
Authors: Faludi Julianna
Published: January 2021

Starting from the Schumpeterian producer-driven understanding of innovation, followed by user-generated solutions and understanding of collaborative forms of co-creation, scholars investigated the drivers and the nature of interactions underpinning success in various ways. Innovation literature has gone a long way, where open innovation has attracted researchers to investigate problems like compatibilities of external resources, networks of innovation, or open source collaboration. Openness itself has gained various shades in the different strands of literature. In this paper the author provides with an overview and a draft evaluation of the different models of open innovation, illustrated with some empirical findings from various fields drawn from the literature. She points to the relevance of transaction costs affecting viable forms of (open) innovation strategies of firms, and the importance to define the locus of innovation for further analyses of different firm and interaction level formations.
Jelenlegi stratégiai tendenciák - a hazai vállalatok összehasonlító elemzése
Authors: Fülöp Gyula , Hódiné Hernádi Bettina
Published: January 2021

Ez a tanulmány a vállalati működés alapvető feltételeinek újraformálódásával kapcsolatos jelenlegi stratégiai kihívásokkal foglalkozik. A hazai cégek kísérleti vizsgálata segítségével bemutatja, hogy a magyarországi nagyvállalatok milyen formában és mértékben vannak felkészülve a jelenlegi stratégiai kihívásokra. A tanulmány megvizsgálja, hogy a stratégiai irányok és válaszlehetőségek hogyan változtak meg az elmúlt öt év folyamán a következő egymással összefüggő területeken: gazdasági globalizáció, vállalati fenntarthatóság, IT-alkalmazások, munkaerő-diverzitás és etikai kompetenciák. Az empirikus felmérés következtetései megbízható alapul szolgálnak a gazdasági szervezetek, vállalkozások stratégiájának megalkotásához.
Vezetőfejlesztés hatékonyan
Authors: Sándor Tímea
Published: January 2021

A vizsgálat célja feltérképezni a 360 fokos visszajelzés önértékelésének eredményei alapján a személyiségjegyek és az érzelmi intelligencia összefüggéseit. A vizsgálat helye a Linamar Hungary Zrt., a vizsgált személyek egy középvezetői munkakör munkavállalói (N=42). A konfliktuskezelés, a meggyőzési készség, a problémamegoldás, az ellenőrzés, a felelősségvállalás, a precizitás, a szorgalom és a teljesítménymenedzsment esetén, ha valaki önmaga szerint jó ezekben a vezetői kompetenciákban, akkor magas EQ-pontszámot ért el. A vezetői kompetenciák fejlesztése segítheti az érzelmi intelligencia fejlődését és fordítva, az érzelmi intelligencia és a személyiségtényezők megfelelő komponenseinek fejlesztése a vezetői kompetenciák bizonyos fejlődését eredményezheti.