bluuebunny/crossref_metadata_2025 huggingface dataset:
Mangrove ecosystem in North Sumatran (Indonesia) forests serves as a suitable habitat for mud crabs (Scylla serrata and S. olivacea)
Authors: KARNIATI RIKA , SULISTIYONO NURDIN , AMELIA RIZKA , SLAMET BEJO , BIMANTARA YUNTHA , Basyuni Mohammad
Published: March 2021

Abstract. Karniati R, Sulistiyono N, Amelia R, Slamet B, Bimantara Y, Basyuni M. 2021. Mangrove ecosystem in North Sumatran (Indonesia) forests serves as a suitable habitat for mud crabs (Scylla serrata and S. olivacea). Biodiversitas 22: 1489-1496. Mud crabs (Scylla serrata and Scylla olivacea) are often found in muddy substrates associated with mangrove vegetation. The habitat of these crabs ranges from tropical estuaries to sheltered subtropical areas, riverbanks, lower river traits, and intertidal areas. These crabs have an important economic value, and it increases the income of the communities living around the mangrove area. This study aims to obtain more information on the environmental factors of habitat for mud crabs (S. serrata and S. olivacea): insights on the effects of abiotic and biotic factors and potential economic value, in the village of Lubuk Kertang, Langkat, North Sumatra, Indonesia. Data were collected by measuring abiotic factors (temperature, pH, salinity, dissolved oxygen, mud depth, distance from the river) and biotic factors (mangrove stand density through canopy cover). The dataset was analyzed using a binary logistic regression analysis with a stepwise method. Results showed that the abiotic factors that contributed to the presence of the mud crab were dissolved oxygen and a mud depth of 68.7%. Meanwhile, the remaining 31.3% that contributed to the presence of mud crabs were abiotic factors (temperature, pH, salinity, distance from rivers) and biotic factors (stand density through canopy cover). The present study suggests that dissolved oxygen and mud depth have an important function in predicting the presence of mud crabs.
Zoonotic potential of gastrointestinal parasite in long-tailed Macaque Macaca fascicularis at Baluran National Park, Situbondo, East Java, Indonesia
Authors: Kurniawati Dyah Ayu , Suwanti Lucia Tri , Lastuti Nunuk D.R. , Kusdarto Setiawan , Suprihati Endang , Mufasirin Mufasirin , Pratiwi Arif
Published: March 2021

Baluran National Park (BNP) is one of the highest number of tourist visit among Indonesian national park. In the past decades, excessive feeding has induced change in macaque behaviour which increased the number of recorded human-macaque interaction. The close contact between macaque and humans can increase the risk of disease transmissions. This study aimed to identify gastro intestinal (GI) parasite in the long-tailed macaque. To provide identification, we adopted morphologic methods. We collected 100 faeces from unidentiﬁed individuals of Long-tailed macaque in BNP. Fecal samples were tested using direct smear and modified sugar floatation techniques. Microscopic examination showed 89% (89/100) samples were found to be positive of GI parasite. The prevalence of protozoa infection was higher (89%) than helminth (83%). The most prevalent GI parasite is Trichostrongylus sp (66%) following with  Entamoeba sp. (53%), Strongyloides sp. (32%), Blastocystis sp. (32%), Trichuris sp.(17%), Giardia sp. (10%) and Enterobius sp. (3%). All of GI parasite that successfully identified have zoonotic concern. In conclusion, GI parasites found in faeces of long-tailed macaque at Baluran National Park  potentially a zoonotic transmission.Keywords : GI Parasite; Long tailed Macaque; Baluran National Park; Zoonosis
Genotoxicity evaluation of Chlorfenapyr in exposed freshwater African catfish Clarias gariepinus using micronucleus test
Authors: Esenowo Imeh Kokoete , Nelson Akwaowo U. , Alimba Chibuisi G. , Ekpo Ndifreke D. , Emmanuel Okeh C.
Published: March 2021

Chlorfenapyr is a new formulated insecticide targeted against insecticide resistant species. Its application in targeting harmful aquatic insects may potentially contaminate aquatic environment. This study is to evaluate its genotoxic effects on non-targeted aquatic biota. The study assessed the genotoxic potentials of chlorfenapyr in African catfish (Clarias gariepinus) using the micronucleus (MN) test. Juvenile stage of C. gariepinus were exposed to different concentrations; 5.00 – 15.00 mgL-1 of chlorfenapyr for 96 hours, peripheral blood was collected through the caudal vein and examined for micronucleus induction in the erythrocytes. The tested concentrations of chlorfenapyr did not elicit significant [F (5, 18) = 0.167, p 0.971] increase in MN formation and other nuclear abnormalities in the peripheral erythrocytes of C. gariepinus. The outcome of this study gives credence to the view that chlorfenapyr is not clastogenic and or aneugenic to non-targeted aquatic vertebrate with reference to fish (C. gariepinus).
Kajian kualitas air laut di perairan Kota Banda Aceh
Authors: Ondara Koko , Jantama Ulung , Agustina Sri , Setiawan Ichsan , Purnawan Syahrul
Published: March 2021

Studying the water quality is significant to protect and for coastal area-use planning in Banda Aceh City, Aceh Province. This study took seawater samples from 13 stations in the northern waters of Banda Aceh on September 10-11 2019. Surface water samples were taken using Van Dorn bottle, which were then tested on 22 types of parameters to evaluate the water quality in the area. In general, the results of tests on various water parameters indicate that the sea waters in Banda Aceh are in good condition. Attention needs to be paid to nitrates and phosphates, which indicate values that exceed water quality standards, thus possible to trigger algal blooms.Keywords:Water qualityNitrateFisheryABSTRAKKajian kualitas air sangat penting untuk melindungi serta untuk perencanaan pemanfaatan ruang pesisir di Kota Banda Aceh, Provinsi Aceh. Penelitian ini mengambil sampel air laut dari 13 stasiun yang di perairan utara Banda Aceh pada 10 – 11 September 2019. Sampel air permukaan laut diambil menggunakan botol Van Dorn, yang kemudian dilakukan uji terhadap 22 jenis parameter untuk mengevaluasi kualitas air di perairan utara Kota Banda Aceh. Secara umum, hasil pengujian pada berbagai parameter air menunjukkan bahwa air laut di Banda Aceh dalam kondisi baik. Perhatian perlu diberikan pada kadar nitrat dan fosfat, yang menunjukkan nilai yang melebihi baku mutu air, dimana memungkinkan untuk memicu pertumbuhan alga yang berlebihan di kawasan tersebut.Kata kunci:Kualitas perairanNitratPerikanan
Coupled dynamic reaction force study of a large-aperture piezoelectric fast steering mirror
Authors: Ran Bing , Wen Lianghua , Zhu Licheng , Yang Kangjian , Yang Ping , Du Rui , Wang Shuai , Xu Bing
Published: March 2021

The reaction force of a large-aperture piezoelectric fast steering mirror (PFSM) has adverse coupling interference for the stability and pointing accuracy of laser beams, and the dynamic characteristics of the reaction force are coupled with the inner components of the PFSM. In order to compensate for and eliminate the reaction force, it is essential to accurately analyze the dynamic characteristics. In this paper, a simplified piezoelectric-coupling model of PFSM is established. The coupling mathematical equations for investigating the characteristics of the reaction force are deducted based on the piezoelectric constitutive equation and Hamiltonian’s principle. Then the coupling characteristics of the reaction force are probed by a finite element (FE) piezoelectric-coupling method. The simulations for three large apertures’ (250, 320, and 400 mm) FE models show that the reaction force has a linear positive correlation with the actuating voltage, and coupled with the materials of the central flexure hinge, the relationship between the reaction force and driving frequency is not completely quadratic. Experiments with the 320 mm aperture are completed, and the testing results are consistent with the mathematical model and the FE piezoelectric-coupling simulation. The dynamic characteristics of the reaction force demonstrated in this paper are significance for the accurate estimation of the reaction force, the design of compensation structure, and the optimization of algorithm for beam jitter controlling.
Model-based optical coherence tomography angiography enables motion-insensitive vascular imaging
Authors: Wei Wei , Cogliati Andrea , Canavesi Cristina
Published: March 2021

We present a significant step toward ultrahigh-resolution, motion-insensitive characterization of vascular dynamics. Optical coherence tomography angiography (OCTA) is an invaluable diagnostic technology for non-invasive, label-free vascular imaging in vivo. However, since it relies on detecting moving cells from consecutive scans, high-resolution OCTA is susceptible to tissue motion, which imposes challenges in resolving and quantifying small vessels. We developed a novel OCTA technique named ultrahigh-resolution factor angiography (URFA) by modeling repeated scans as generative latent variables, with a common variance representing shared features and a unique variance representing motion. By iteratively maximizing the combined log-likelihood probability of these variances, the unique variance is largely separated. Meanwhile, features in the common variance are decoupled, in which vessels with dynamic flow are extracted from tissue structure by integrating high-order factors. Combined with Gabor-domain optical coherence microscopy, URFA successfully extracted high-resolution cutaneous vasculature despite severe involuntary tissue motion and scanner oscillation, significantly improving the visualization and characterization of micro-capillaries in vivo. Compared with the conventional approach, URFA reduces motion artifacts by nearly 50% on average, evaluated on local differences.
Surface plasmon resonances boost the transverse magneto-optical Kerr effect in a CoFeB slab covered by a subwavelength gold grating for highly sensitive detectors
Authors: Wang Qiao , Yao Haizi , Feng Yefeng , Deng Xiaoqian , Yang Bingwen , Xiong Deping , He Miao , Zhang Weiwei
Published: March 2021

Herein, we have theoretically investigated the sensing performance—including enormous increase in the sensitivity and figure of merit (FOM)—of a magneto-optical surface plasmon resonance (MOSPR) sensor, which is based on the transverse magneto-optical Kerr effect (T-MOKE) in a ferromagnet coupled with a noble-metal grating. Specifically, we propose to use a CoFeB magnetic slab covered by a subwavelength, periodic gold grating configured as a magnetoplasmonic heterostructure. In such a device, sharp, Fano-like T-MOKE signals of high amplitude can be achieved due to the surface plasmon resonances (SPRs) excited in the presence of the gold grating, especially after optimizing the grating period. Tiny changes in the refractive index of an analyte surrounding the MOSPR sensor can be measured by analyzing the shift in the angle of incidence of the resonance positions of the T-MOKE signals. By calculating these resonance positions, we have demonstrated that it is possible to achieve a considerable sensitivity of 105° RIU−1 and a FOM as high as ∼102. Such a MOSPR sensing system can be exploited in biosensors with high detection limits.
Photoinduced Kerr rotation spectroscopy for microscopic spin systems using heterodyne detection
Authors: Mitsumori Yasuyoshi , Uedaira Kentaro , Shimomura Satoshi , Edamatsu Keiichi
Published: March 2021

We develop a transient photoinduced Kerr rotation spectroscopy technique using a heterodyne detection scheme to study spin dynamics of microscopic quantum states in solids, such as single quantum dots and spin helixes. The use of the heterodyne beat note signal generated by the interference of the frequency-shifted probe and reference pulses realizes the Kerr rotation measurements in combination with micro-spectroscopy, even when the probe pulse propagates collinearly with the strong pump pulse, which resonantly excites the probing state. In addition, the interference gives an optical amplification of the Kerr signal, which provides a clear observation of the photoinduced spin dynamics by the weak probe intensity. Here, we present results of Kerr rotation measurements for a single quantum dot exciton, which shows a maximum rotation angle of few µrad.
Pure rotational Raman lidar for full-day troposphere temperature measurement at Zhongshan Station (69.37°S, 76.37°E), Antarctica
Authors: Liu Fuchao , Wang Rui , Yi Fan , Huang Wentao , Ban Chao , Pan Weilin , Wang Zhangjun , Hu Hongqiao
Published: March 2021

A pure rotational Raman lidar (PRRL) for full-day troposphere temperature measurement was deployed in February 2020 at Zhongshan Station (69.37°S, 76.37°E), Antarctica, by the 36th Chinese National Antarctic Research Expedition. The PRRL emits a 532.23-nm laser light and employs a 203.2-mm telescope to collect atmospheric backscatter. Cubic nonpolarizing beam splitters are introduced to yield a compact optics arrangement. A quasi-single-line-extraction technique is proposed for extracting the molecular Stokes line signals. A lidar container with a window system is customized to house the whole PRRL system for long-term stable operation. An approach using a laser plummet is developed for fast and convenient adjustment of the telescope zenithward. A home-made calibration module is utilized for straightforward visual optics adjustment with ∼35.3-μrad angular positioning accuracy. Both typical daytime and nighttime temperature measurement examples are presented to verify the lidar performance. From a 30-h continuous temperature measurement result, it is found the tropopause is located at ∼10.8 km above ground level with a mean temperature of ∼203 K; significant temperature variability occurs only at the inversion areas, while off which the 1-h temperature profiles are relatively similar in form with an average lapse rate of -8.3 K/km.
Making path selection faster: a routing algorithm for ONoC
Authors: Zhu Lijing , Gu Huaxi , Yang Yintang , Chen Yawen
Published: March 2021

Optical network-on-chip (ONoC) is an effective communication architecture to realize high performance and energy efﬁciency. Diverse routing algorithms are proposed to avoid the congestion, tolerate the faults, and reduce the insertion loss or energy consumption. However, existing algorithms did not consider the characteristic optical circuit-switching of ONoC, which aggravates the network congestion and degrades the associated performance severely. In this paper, by exploiting congestion prediction technique, we propose a new routing algorithm for ONoC, named loophole-routing, to improve the success rate of path-setup and decrease the latency. We use the congestion prediction technique to analyze the latency and predict the port condition caused by the network congestion. Theoretical analysis and experimental results of different synthetic traffic patterns show that the loophole-routing improves network latency over XY routing and OE-turn routing by 15.56%, 25.71%, 18.92%, 66.67% and 42.86% under uniform, hotspot1, hotspot2, transpose2 and transpose3 traffic patterns while improving the saturation throughput by 31.43%, 34.33%, 35.29%, 67.86% and 99.5% under uniform, hotspot1, hotspot2, transpose2 and transpose3 traffic patterns on average than XY routing. In addition, our proposed loophole-routing has the benefits of high path diversity and adaptive degree and low computing complexity and overhead and the potential to make fault-tolerant path selection.
Aberration correction based on a pre-correction convolutional neural network for light-field displays
Authors: Yu Xunbo , Li Hanyu , Sang Xinzhu , Su Xiwen , Gao Xin , Liu Boyang , Chen Duo , Wang Yuedi , Yan Binbin
Published: March 2021

Lens aberrations degrade the image quality and limit the viewing angle of light-field displays. In the present study, an approach to aberration reduction based on a pre-correction convolutional neural network (CNN) is demonstrated. The pre-correction CNN is employed to transform the elemental image array (EIA) generated by a virtual camera array into a pre-corrected EIA (PEIA). The pre-correction CNN is built and trained based on the aberrations of the lens array. The resulting PEIA, rather than the EIA, is presented on the liquid crystal display. Via the optical transformation of the lens array, higher quality 3D images are obtained. The validity of the proposed method is confirmed through simulations and optical experiments. A 70-degree viewing angle light field display with the improved image quality is demonstrated.
Layered antisymmetry-constructed clipped optical OFDM for low-complexity VLC systems
Authors: Bai Ruowen , Hranilovic Steve
Published: March 2021

In this paper, antisymmetry-constructed clipped optical orthogonal frequency division multiplexing (AC-OFDM) is proposed for visible light communication (VLC) systems, in which an antisymmetry property is imposed directly in time domain. AC-OFDM has nearly the same spectral efficiency and peak-to-average power ratio (PAPR) as traditional asymmetrically clipped optical OFDM (ACO-OFDM) but is less complex to implement. Layered AC-OFDM (LAC-OFDM) is then proposed as an extension to further improve spectral efficiency, where different layers of AC-OFDM signals are added in the time domain and transmitted simultaneously. Computational complexity analysis and numerical results show that LAC-OFDM has nearly the same spectral efficiency as layered asymmetrically clipped optical OFDM (LACO-OFDM) and enhanced unipolar OFDM (eU-OFDM) but is less complex. Specifically, LAC-OFDM requires less than half the multiplication and addition operations compared to the comparable LACO-OFDM scheme. Additionally, a pairwise iterative receiver for LAC-OFDM is proposed and its computational complexity is analysed. Monte Carlo simulation results show that LAC-OFDM requires nearly the same optical signal-to-noise ratio (OSNR) to achieve the same BER performance as LACO- and eU-OFDM.
Infrared all-dielectric Kerker metasurfaces
Authors: Fan Kebin , Shadrivov Ilya V. , Miroshnichenko Andrey E. , Padilla Willie J.
Published: March 2021

The unidirectional scattering of electromagnetic waves in the backward and forward direction, termed Kerkers’ first and second conditions, respectively, is a prominent feature of sub-wavelength particles, which also has been found recently in all-dielectric metasurfaces. Here we formulate the exact polarizability requirements necessary to achieve both Kerker conditions simultaneously with dipole terms only and demonstrate its equivalence to so-called “invisible metasurfaces”. We further describe the perfect absorption mechanism in all-dielectric metasurfaces through development of an extended Kerker formalism. The phenomena of both invisibility and perfect absorption is shown in a 2D hexagonal array of cylindrical resonators, where only the resonator height is modified to switch between the two states. The developed framework provides critical insight into the range of scattering response possible with all-dielectric metasurfaces, providing a methodology for studying exotic electromagnetic phenomena.
Rotational Doppler effect detection by LG beams with a nonzero radial index
Authors: Qiu Song , Ren Yuan , Liu Tong , Li Zhimeng , Liu Zhengliang , Wang Chen , Ding You , Sha Qimeng
Published: March 2021

The capability to detect the rotational speed of non-cooperative targets in a long distance is a difficult problem to be solved. In recent years, vortex light provides a feasible solution for the measurement of rotational speed for its spiral phase and the orbital angular momentum. Laguerre-Gaussian (LG) mode, as the typical vortex beam, has been widely employed in rotational Doppler effect (RDE) experiments. Here, we show that the nonzero radial index LG beam not only has a specific physical meaning but also can enhance the light intensity and the amplitude of RDE frequency signal relative to a zero radial index LG beam. To this end, we theoretically analyze the reason of intensity enhancement of a nonzero radial index beam and verify the conclusion in a variable control experiment. Our study provides a new aspect of LG beams that can be considered in rotational speed detection based on RDE. It may produce an improvement of the detection range of rotating targets in practical applications.
Microscope autofocus algorithm based on number of image slope variations
Authors: Weng Jing-Feng , Lu Guo-Hao , Weng Chun-Jen , Lin Yu-Hsin , Liu Chao-Feng , Vincke Robbie , Ting Hsiao-Chun , Chang Ting-Ting
Published: March 2021

This paper presents a passive autofocus algorithm applicable to interferometric microscopes. The proposed algorithm uses the number of slope variations in an image mask to locate the focal plane (based on focus-inflection points) and identify the two neighboring planes at which fringes respectively appear and disappear. In experiments involving a Mirau objective lens, the proposed algorithm matched the autofocusing performance of conventional algorithms, and significantly outperformed detection schemes based on zero-order interference fringe in dealing with all kinds of surface blemish, regardless of severity. In experiments, the proposed algorithm also proved highly effective in cases without fringes.
Imaging localized fast optical signals of neural activation with optical coherence tomography in awake mice
Authors: Tang Jianbo , Cheng Xiaojun , Kilic Kivilcim , Devor Anna , Lee Jonghwan , Boas David A.
Published: March 2021

We report optical coherence tomography (OCT) imaging of localized fast optical signals (FOSs) arising from whisker stimulation in awake mice. The activated voxels were identified by fitting the OCT intensity signal time course with a response function over a time scale of a few hundred milliseconds after the whisker stimulation. The significantly activated voxels were shown to be localized to the expected brain region for whisker stimulation. The ability to detect functional stimulus-evoked, depth-resolved FOS with intrinsic contrast from the cortex provides a new tool for neural activity studies.
Polygonal patterns of confined light
Authors: Sedov Evgeny , Sedova Irina , Arakelian Sergey , Kavokin Alexey
Published: March 2021

We propose a technique for the generation of polygonal optical patterns in real space using a combined effect of the spin–orbit interaction and confinement of light in the plane of a dielectric optical microcavity. The spin–orbit interaction emerging from the splitting in transverse electric (TE) and transverse magnetic (TM) optical modes of the microcavity gives rise to oscillations in space of propagating macroscopic wave packets of polarized photons. Confined in a harmonic potential, the latter follow closed trajectories of a polygonal form. We demonstrate the possibility of excitation by a continuous wave resonant optical pumping of polygonal optical patterns with a controllable (both even and odd) number of vertices.
Hybrid fs/ps vibrational coherent anti-Stokes Raman scattering for simultaneous gas-phase N2/O2/CO2 measurements
Authors: Zhao Huijie , Tian Ziyang , Li Yan , Wei Haoyun
Published: March 2021

Single-shot, 1-kHz measurements of temperatures and mole fraction ratios along with theoretical modeling for gas-phase

N

2

,

O

2

, and

C
O

2

are demonstrated using hybrid femtosecond/picosecond (fs/ps) vibrational coherent anti-Stokes Raman scattering (CARS). The combination of broadband pump and Stokes pulses covers a spectral range over

1800

c
m

−
1

while the narrowband probe pulses generated from a quasi-common-path second harmonic bandwidth compressor (QCP-SHBC) resolves the molecular structures with a bandwidth of

∼

7

c
m

−
1

. Temperature results of 1700–2000 K in methane/air fuel-lean flames show state-of-the-art inaccuracies of less than

∼

3

%

and precision less than 2%. Mole fraction ratios inaccuracy at room temperature is

∼

5

%

, and precision at flame temperatures are 6%–8%.
Two-term Reynolds–McCormick phase function parameterization better describes light scattering by microalgae and mineral hydrosols
Authors: Harmel Tristan , Agagliate Jacopo , Hieronymi Martin , Gernez Pierre
Published: March 2021

The presence of hydrosols, taken as suspension of micro- or macroscopic material in water, strongly alters light propagation and thus the radiance distribution within a natural or artificial water volume. Understanding of hydrosols’ impacts on light propagation is limited by our ability to accurately handle the angular scattering phase function inherent to complex material such as suspended sediments or living cells. Based on actual quality-controlled measurements of sediments and microalgae, this Letter demonstrates the superiority of a two-term five-parameter empirical phase function as recently proposed for scattering by nanoparticle layers [Nanoscale 11, 7404 (2019)NANOHL2040-336410.1039/C9NR01707K]. The use of such phase function parameterizations presents new potentialities for various radiative transfer and remote sensing applications related to an aquatic environment.
Breakdown of Maxwell Garnett theory due to evanescent fields at deep-subwavelength scale
Authors: Dong Ting , Luo Jie , Chu Hongchen , Xiong Xiang , Peng Ruwen , Wang Mu , Lai Yun
Published: March 2021

Deep-subwavelength all-dielectric composite materials are believed to tightly obey the Maxwell Garnett effective medium theory. Here, we demonstrate that the Maxwell Garnett theory could break down due to evanescent fields in deep-subwavelength dielectric structures. By using two- and three-dimensional dielectric composite materials with inhomogeneities at a scale of

λ
/
100

, we show that local evanescent fields generally occur near the dielectric inhomogeneities. When tiny absorptive constituents are placed there, the absorption and transmission of the whole composite will show strong dependence on the positions of the absorptive constituents. The Maxwell Garnett theory fails to predict such position-dependent characteristics because it averages out the evanescent fields. By taking the distribution of the evanescent fields into consideration, we have made a correction to the Maxwell Garnett theory so that the position-dependent characteristics become predictable. We reveal not only the breakdown of the Maxwell Garnett theory, but also a unique phenomenon of “invisible” loss induced by the prohibition of electric fields at deep-subwavelength scales. We believe our work promises a route to control the macroscopic properties of composite materials without changing their composition, which is beyond the traditional Maxwell Garnett theory.
High-power, electronically controlled source of user-defined vortex and vector light beams based on a few-mode fiber amplifier
Authors: Lin Di , Carpenter Joel , Feng Yutong , Jung Yongmin , Alam Shaif-ul , Richardson David J.
Published: March 2021

Optical angular momentum (OAM)-based structured light beams provide an additional degree of freedom for practical applications ranging from optical communication to laser-based material processing. Many techniques exist for generating such beams within laser sources and these primarily rely upon the use of specially designed optical components that limit laser power scaling and ready tunability of the topological charge and polarization of the output OAM beams. Here we show that some of these limitations can be overcome by employing a computer controlled reflective phase-only spatial light modulator to adaptively tailor the input (and subsequent output) beam wavefront and polarization in a few-mode fiber amplifier. In this way modal-coupling-induced beam distortion within the fiber amplifier can be mitigated and we are able to generate at will any desired supported spatial mode guided in the fiber, including conventional linearly polarized (LP) modes, scalar OAM modes, and cylindrical vector modes, at average powers

>
10
  
W

and with a peak power of

>
11
  
kW

. Our results pave the way to the realization of practical high-power structured laser sources with tunable chirality and polarization.
Immensely enhanced color-adjustable upconversion fluorescence in electron donor-acceptor exciplex chromophores doped with fluorescent emitters
Authors: Chen Zhen , Zhou Qian , Du Huitian , Yu Yuan , Zhang Chuang , Han Shenghao , Pang Zhiyong
Published: March 2021

Two-photon excited fluorescence materials usually suffer from inefficient two-photon absorption (TPA) and nonradiative excited states. Here, upconversion fluorescence in an electron donor-acceptor (DA) exciplex doped with fluorescent emitters are systematically investigated. It has been found that the undoped DA exciplex exhibits enhancements of ∼129% and ∼365% in upconversion fluorescence compared to donor- and acceptor-only systems, respectively. Interestingly, photoluminescence quantum yields (PLQYs) up to ∼98.65% were measured and immensely enhanced upconversion fluorescence was observed after doping various fluorescent emitters into the DA exciplex. Our results reveal the existence of two-photon excited energy harvesting in a thermally activated delayed fluorescence (TADF) DA exciplex doped with fluorescent emitters, via reverse intersystem crossing followed by rapid Förster resonance energy transfer. Moreover, the additional gain mechanism related to intermolecular CT interaction that occurs at the TPA stage is found in the TADF DA exciplex system.
1.7-μm dissipative soliton Tm-doped fiber laser
Authors: Chen Ji-Xiang , Li Xiang-Yue , Li Ti-Jian , Zhan Ze-Yu , Liu Meng , Li Can , Luo Ai-Ping , Zhou Pu , Wong Kenneth K.-Y. , Xu Wen-Cheng , Luo Zhi-Chao
Published: March 2021

We report on the dissipative soliton generation in a 1.7-μm net-normal dispersion Tm-doped fiber laser by nonlinear polarization rotation technique. An intra-cavity bandpass filter was employed to suppress the long-wavelength emission, while the cavity dispersion was compensated by a segment of ultrahigh numerical aperture (UHNA4) fiber. The dissipative soliton with a central wavelength of 1746 nm was obtained, covering a spectral range from 1737 nm to 1754 nm. The de-chirped duration and energy of the dissipative soliton were 370 fs and 0.2 nJ, respectively. In addition, the dynamics of multiple dissipative solitons were also investigated. Through optimization of the cavity dispersion, the 50 nm broadband dissipative soliton with de-chirped pulse duration of 230 fs could be achieved. The development of dissipative soliton seed laser represents the first step in achieving the chirped pulse amplification system at the 1.7-μm wave band, which would find potential applications in fields such as biomedical imaging and material processing.
Insights into the molecular basis of tick-borne encephalitis from multiplatform metabolomics
Authors: Du YanDan , Mi ZhiHui , Xie YaPing , Lu DeSheng , Zheng HaiJun , Sun Hui , Zhang Meng , Niu YiQing
Published: March 2021

Background

Tick-borne encephalitis virus (TBEV) is the most prevalent arbovirus, with a tentative estimate of 10,000 to 10,500 infections occurring in Europe and Asia every year. Endemic in Northeast China, tick-borne encephalitis (TBE) is emerging as a major threat to public health, local economies and tourism. The complicated array of host physiological changes has hampered elucidation of the molecular mechanisms underlying the pathogenesis of this disease.

Methodology/Principle findings

System-level characterization of the serum metabolome and lipidome of adult TBEV patients and a healthy control group was performed using liquid chromatography tandem mass spectrometry. By tracking metabolic and lipid changes during disease progression, crucial physiological changes that coincided with disease stages could be identified. Twenty-eight metabolites were significantly altered in the sera of TBE patients in our metabolomic analysis, and 14 lipids were significantly altered in our lipidomics study. Among these metabolites, alpha-linolenic acid, azelaic acid, D-glutamine, glucose-1-phosphate, L-glutamic acid, and mannose-6-phosphate were altered compared to the control group, and PC(38:7), PC(28:3;1), TAG(52:6), etc. were altered based on lipidomics. Major perturbed metabolic pathways included amino acid metabolism, lipid and oxidative stress metabolism (lipoprotein biosynthesis, arachidonic acid biosynthesis, leukotriene biosynthesis and sphingolipid metabolism), phospholipid metabolism and triglyceride metabolism. These metabolites were significantly perturbed during disease progression, implying their latent utility as prognostic markers.

Conclusions/Significance

TBEV infection causes distinct temporal changes in the serum metabolome and lipidome, and many metabolites are potentially involved in the acute inflammatory response and immune regulation. Our global analysis revealed anti- and pro-inflammatory processes in the host and changes to the entire metabolic profile. Relationships between metabolites and pathologies were established. This study provides important insight into the pathology of TBE, including its pathology, and lays the foundation for further research into putative markers of TBE disease.
Dog ownership practices and responsibilities for children’s health in terms of rabies control and prevention in rural communities in Tanzania
Authors: Sikana Lwitiko , Lembo Tiziana , Hampson Katie , Lushasi Kennedy , Mtenga Sally , Sambo Maganga , Wight Daniel , Coutts Jane , Kreppel Katharina
Published: March 2021

Interventions tackling zoonoses require an understanding of healthcare patterns related to both human and animal hosts. The control of dog-mediated rabies is a good example. Despite the availability of effective control measures, 59,000 people die of rabies every year worldwide. In Tanzania, children are most at risk, contributing ~40% of deaths. Mass dog vaccination can break the transmission cycle, but reaching the recommended 70% coverage is challenging where vaccination depends on willingness to vaccinate dogs. Awareness campaigns in communities often target children, but do not consider other key individuals in the prevention chain. Understanding factors related to dog ownership and household-level responsibility for dog vaccination and child health is critical to the design of vaccination strategies. We investigated who makes household decisions about dogs and on health care for children in rural Tanzania. In the Kilosa district, in-depth interviews with 10 key informants were conducted to inform analysis of data from a household survey of 799 households and a survey on Knowledge Attitudes and Practices of 417 households. The in-depth interviews were analysed using framework analysis. Descriptive analysis showed responsibilities for household decisions on dogs’ and children’s health. Multivariate analysis determined factors associated with the probability of dogs being owned and the number of dogs owned, as well as factors associated with the responsibility for child health. Dog ownership varied considerably between villages and even households. The number of dogs per household was associated with the size of a household and the presence of livestock. Children are not directly involved in the decision to vaccinate a dog, which is largely made by the father, while responsibility for seeking health care if a child is bitten lies with the mother. These novel results are relevant for the design and implementation of rabies interventions. Specifically, awareness campaigns should focus on decision-makers in households to improve rabies prevention practices and on the understanding of processes critical to the control of zoonoses more broadly.
Development and validation of a stability indicating RP-HPLC-DAD method for the determination of bromazepam
Authors: Darwish Hany W. , Ali Nesma A. , Naguib Ibrahim A. , El Ghobashy Mohamed R. , Al-Hossaini Abdullah M. , Abdelrahman Maha M.
Published: March 2021

A reliable, selective and sensitive stability-indicating RP-HPLC assay was established for the quantitation of bromazepam (BMZ) and one of the degradant and stated potential impurities; 2-(2-amino-5-bromobenzoyl) pyridine (ABP). The assay was accomplished on a C18column (250 mm × 4.6 mm i.d., 5 μm particle size), and utilizing methanol-water (70: 30, v/v) as the mobile phase, at a flow rate of 1.0 ml min-1. HPLC detection of elute was obtained by a photodiode array detector (DAD) which was set at 230 nm. ICH guidelines were adhered for validation of proposed method regarding specificity, sensitivity, precision, linearity, accuracy, system suitability and robustness. Calibration curves of BMZ and ABP were created in the range of 1–16 μg mL-1with mean recovery percentage of 100.02 ± 1.245 and 99.74 ± 1.124, and detection limit of 0.20 μg mL-1and 0.24 μg mL-1respectively. BMZ stability was inspected under various ICH forced degradation conditions and it was found to be easily degraded in acidic and alkaline conditions. The results revealed the suitability of the described methodology for the quantitation of the impurity (ABP) in a BMZ pure sample. The determination of BMZ in pharmaceutical dosage forms was conducted with the described method and showed mean percentage recovery of 99.39 ± 1.401 and 98.72 ± 1.795 (n = 6), respectively. When comparing the described procedure to a reference HPLC method statistically, no significant differences between the two methods in regard to both accuracy and precision were found.
Argentine Black and White Tegu (Salvator merianae) can survive the winter under semi-natural conditions well beyond their current invasive range
Authors: Goetz Scott M. , Steen David A. , Miller Melissa A. , Guyer Craig , Kottwitz Jack , Roberts John F. , Blankenship Emmett , Pearson Phillip R. , Warner Daniel A. , Reed Robert N.
Published: March 2021

The Argentine Black and White Tegu (Salvator merianae, formerly Tupinambis merianae) is a large lizard from South America. Now established and invasive in southern Florida, and it poses threats to populations of many native species. Models suggest much of the southern United States may contain suitable temperature regimes for this species, yet there is considerable uncertainty regarding either the potential for range expansion northward out of tropical and subtropical zones or the potential for the species establishing elsewhere following additional independent introductions. We evaluated survival, body temperature, duration and timing of winter dormancy, and health of wild-caught tegus from southern Florida held in semi-natural enclosures for over a year in Auburn, Alabama (> 900 km northwest of capture location). Nine of twelve lizards emerged from winter dormancy and seven survived the greater-than-one-year duration of the study. Average length of dormancy (176 d) was greater than that reported in the native range or for invasive populations in southern Florida and females remained dormant longer than males. Tegus grew rapidly throughout the study and the presence of sperm in the testes of males and previtellogenic or early vitellogenic follicles in female ovaries at the end of our study suggest the animals would have been capable of reproduction the following spring. The survival and overall health of the majority of adult tegus in our study suggests weather and climate patterns are unlikely to prevent survival following introduction in many areas of the United States far from their current invasive range.
Re-evaluating Scythian lifeways: Isotopic analysis of diet and mobility in Iron Age Ukraine
Authors: Ventresca Miller Alicia R. , Johnson James , Makhortykh Sergey , Gerling Claudia , Litvinova Ludmilla , Andrukh Svetlana , Toschev Gennady , Zech Jana , le Roux Petrus , Makarewicz Cheryl , Boivin Nicole , Roberts Patrick
Published: March 2021

The Scythians are frequently presented, in popular and academic thought alike, as highly mobile warrior nomads who posed a great economic risk to growing Mediterranean empires from the Iron Age into the Classical period. Archaeological studies provide evidence of first millennium BCE urbanism in the steppe while historical texts reference steppe agriculture, challenging traditional characterizations of Scythians as nomads. However, there have been few direct studies of the diet and mobility of populations living in the Pontic steppe and forest-steppe during the Scythian era. Here, we analyse strontium, oxygen, and carbon isotope data from human tooth enamel samples, as well as nitrogen and carbon isotope data of bone collagen, at several Iron Age sites across Ukraine commonly associated with ‘Scythian’ era communities. Our multi-isotopic approach demonstrates generally low levels of human mobility in the vicinity of urban locales, where populations engaged in agro-pastoralism focused primarily on millet agriculture. Some individuals show evidence for long-distance mobility, likely associated with significant inter-regional connections. We argue that this pattern supports economic diversity of urban locales and complex trading networks, rather than a homogeneous nomadic population.
Partner intimate touch is associated with increased interpersonal closeness, especially in non-romantic partners
Authors: Prause Nicole , Siegle Greg J. , Coan James
Published: March 2021

Relationship closeness promotes desirable health outcomes. Most interventions to increase relationship closeness are verbal, which may not suit all couples. We consider whether Orgasmic Meditation (OM), a structured, partnered, largely non-verbal practice that includes genital touch, also increases relationship closeness. We hypothesized that OM would increase feelings of closeness for both romantic and non-romantic partners. This is important, because intimate touch with non-romantic partners is commonly considered deleterious by clinicians, which may inadvertently increase feelings of shame. Dyads (n = 125) reported their feelings of closeness before and after OM. Approximately half of the participants were romantic partners, while the other half only engaged in OM together (non-romantic). Closeness after OM increased on average across participants. Non-romantic dyads increased self-other overlap more than romantic dyads. These data support that a partnered, largely non-verbal practice is associated with increased feelings of closeness in the moment, including for individuals who are not in a romantic relationship.
Women’s experiences of counselling in cases of a screen-positive prenatal screening result
Authors: Vuorenlehto Leena , Hinnelä Kaisa , Äyräs Outi , Ulander Veli-Matti , Louhiala Pekka , Kaijomaa Marja
Published: March 2021

Objective

To study women’s apprehensions, understanding and experiences of counselling concerning a screen-positive result in screening for fetal chromosomal defects.

Methods

A questionnaire study including different steps of the prenatal screening process was carried out in Helsinki University Hospital. Women’s experiences concerning counselling immediately after a screen-positive result and during further examinations in the Fetal Medicine Unit (FMU) were analyzed.

Results

143 women filled in the questionnaire. Less than half of the women considered the primary counselling after a screen-positive result to be explicit (43.9%) and sufficient (43.1%). In the FMU, 88.3% and 89.8% of women were satisfied with the explicitness and sufficiency of counselling. Most women (75%) experienced worry before further examinations but less than half (45%) had considered their personal values concerning diagnostic tests. Half (50.5%) of women expected the worry to continue even if diagnostic tests turn out normal. Most (81%) women were aware that diagnostic tests are voluntary and were confident (85.3%) with their decision to participate.

Conclusions

After a screen-positive result, women have unanswered questions, experience anxiety and confusion. The possibility of an abnormal screening result is not seriously considered beforehand. To enable an informed consent for prenatal screening, improvements in prescreening counselling during the first visits of antenatal care need to be made.
Genome-wide analysis of nearly all the victims of a 6200 year old massacre
Authors: Novak Mario , Olalde Iñigo , Ringbauer Harald , Rohland Nadin , Ahern James , Balen Jacqueline , Janković Ivor , Potrebica Hrvoje , Pinhasi Ron , Reich David
Published: March 2021

Paleogenomic and bioanthropological studies of ancient massacres have highlighted sites where the victims were male and plausibly died all in battle, or were executed members of the same family as might be expected from a killing intentionally directed at subsets of a community, or where the massacred individuals were plausibly members of a migrant community in conflict with previously established groups, or where there was evidence that the killing was part of a religious ritual. Here we provide evidence of killing on a massive scale in prehistory that was not directed to a specific family, based on genome-wide ancient DNA for 38 of the 41 documented victims of a 6,200 year old massacre in Potočani, Croatia and combining our results with bioanthropological data. We highlight three results: (i) the majority of individuals were unrelated and instead were a sample of what was clearly a large farming population, (ii) the ancestry of the individuals was homogenous which makes it unlikely that the massacre was linked to the arrival of new genetic ancestry, and (iii) there were approximately equal numbers of males and females. Combined with the bioanthropological evidence that the victims were of a wide range of ages, these results show that large-scale indiscriminate killing is a horror that is not just a feature of the modern and historic periods, but was also a significant process in pre-state societies.
Integrated biological and chemical characterisation of a pair of leonardesque canal lock gates
Authors: Zoia Luca , Salanti Anika , Giorgione Claudio , Gentili Rodolfo , Citterio Sandra , Gandolfi Isabella , Franzetti Andrea , Orlandi Marco
Published: March 2021

The Museo Nazionale della Scienza e della Tecnologia “Leonardo da Vinci” in Milan is exposing two pairs of canal lock gates, used to control the water flow in Milan canal system, whose design appears in the Leonardo’s Codex Atlanticus. The wood present in the gates has been deeply characterised by mean of a multidisciplinary investigation involving i) DNA barcoding of wood fragments; ii) microbial community characterisation, and iii) chemical analyses. DNA barcoding revealed that two fragments of the gates belonged to wood species widely used in the middle age: Fagus sylvatica and Picea abies. The chemical characterisations were based on the use of ionic liquid as dissolving medium in order to analyse the entire cell wall material by means of Gel Permeation Chromatography (GPC) and 2D-NMR-HSQC techniques. This multidisciplinary analytical approach was able to highlight the complex nature of the degradation occurred during the gate operation (XVI-XVIII centuries): an intricate interplay between microbial populations (i.e. Shewanella), inorganic factors (i.e. iron from nails), physical factors and the lignocellulosic material.