bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mid-infrared free space wavelength beam splitter based on dual frequency reflective metalens
Authors: Wu Boqi , Chi Yaodan , Zhang Hengxu , Zhao Chunlei , Zhao Yang , Lv Sa , Yang Jia 
Published: June 2022

Abstract
We present a reflective metalens with a hybrid antenna structure, which can realize the beam splitting function of two wavelengths in free space. A key feature of our design is the presence of phase-independent regulation at two different wavelengths in each nanoresonator, which can generate a specific phase or a continuous sweep in the range of 0° to more than 300°. To demonstrate the wavefront manipulation ability of the array, we simulated the characteristics of wavelength beam splitting, especially the free space wavelength beam splitter with a focal length of 300 μm and a relative focal position of 100 μm.
SAP: A Secure Low-latency Protocol for Mitigating High Computation Overhead in WI-FI Networks
Authors: Jain Vineeta , Wetzker Ulf , Laxmi Vijay , Gaur Manoj Singh , Mosbah Mohamed , Mery Dominique 
Published: June 2022

<p> The increase in popularity of wireless networks in industrial, embedded, medical and public sectors has made them an appealing attack surface for attackers who exploit the vulnerabilities in network protocols to launch attacks such as Evil Twin, Man-in-the-middle, sniffing, <u>etc</u>., which may result in economic and non-economic losses. To protect wireless networks against such attacks, IEEE 802.11 keep updating the protocol standards with new and more secure versions. There has always been a direct correlation between attacks and the improvement of protocol standards. As the sophistication of attacks increases, protocol standards tend to move towards higher security, resulting in a significant rise in both latency and computational overhead, and severe degradation in the performance of low-latency applications such as Industrial Internet of Things (<u>IIoT</u>), automotive, robotics, <u>etc</u>. In this paper, we make the first attempt to highlight the importance of both latency and security in wireless networks from implementation and performance perspective. We make a review of existing IEEE 802.11 protocols in terms of security offered and overhead incurred to substantiate the fact that there is a need of a protocol which in addition to providing optimum security against attacks also maintains the latency and overhead. We also propose a secure and low-latency protocol known as Secure Authentication Protocol (SAP) which operates in two phases - registration and authentication, where the first phase is a one time process implemented using asymmetric cryptography and the second phase is implemented using symmetric cryptography. The protocol is structured in a way that it maintains the original structure of IEEE 802.11 protocols and performs both phases using fewer messages than existing protocols. By simulating the protocol using well-established <u>OMNeT</u>++ simulator, we proved that the proposed protocol incurs a low computation overhead, making it ideal for low-latency applications. We extensively verified the security properties of the proposed protocol using formal verification through widely-accepted <u>Scyther</u> tool. Finally, we perform a comparative analysis of SAP with existing IEEE 802.11 wireless network protocols to highlight the improvement.</p>
Long-term Optical Monitoring of the TeV BL Lacertae Object 1ES 2344 + 514
Authors: Cai J. T. , Kurtanidze S. O. , Liu Y. , Kurtanidze O. M. , Nikolashvili M. G. , Xiao H. B. , Fan J. H. 
Published: June 2022

Abstract
Variability is one of the main observational characteristics of blazars. Studying variability is an efficient method to reveal the nature of active galactic nuclei. In the present work, we report optical R-band photometry observations of a TeV blazar, 1ES 2344 + 514, carried out with a 70 cm telescope in the period of 1998 July–2017 November at Abastumani Observatory, Georgia. Based on the optical R-band observations, the optical variation behaviors on both short timescales and long timescales are investigated. Three methods (Jurkevich, discrete correlation function, and power spectrum analysis) are used to investigate periodicity in the light curve. In addition, combined with multiwavelength data, the jet physical properties are discussed. The following conclusions are drawn: (1) A variability of ΔR = 0.155 mag (15.356 − 15.201 mag) over a timescale of ΔT = 12.99 minutes is detected during our 628 days of monitoring. (2) According to the Kelvin–Helmholtz thermal instability, if the magnetic field intensity (B) for the source is greater than a critical value (B

c
), it will reduce the incidence of intraday variations in the light curves. (3) The physical parameters of the dissipation region are obtained by fitting the spectral energy distribution with a one-zone synchrotron self-Compton model for the average and flare states. (4) The three methods show that there are periods of P = 2.72 ± 0.47 yr, P = 1.61 ± 0.18 yr, P = 1.31 ± 0.17 yr, and P = 1.05 ± 0.07 yr. When a binary black hole system is adopted with a period of P = 2.72 ± 0.41 yr, we obtain the orbital parameters for the binary black hole system as follows: M = 8.08 × 109
M
⊙, the sum of the semiaxes is r = 7.18 × 1016 cm, and the lifetime of the binary black hole is τ
merge = 6.24 × 102 yr.
Scalar Quadratic Maximum-likelihood Estimators for the CMB Cross-power Spectrum
Authors: Chen Jiming , Ghosh Shamik , Zhao Wen 
Published: June 2022

Abstract
Estimating the cross-correlation power spectra of the cosmic microwave background, in particular, the TB and EB spectra, is important for testing parity symmetry in cosmology and diagnosing insidious instrumental systematics. The quadratic maximum-likelihood (QML) estimator provides optimal estimates of the power spectra, but it is computationally very expensive. The hybrid pseudo-C

ℓ
estimator is computationally fast but performs poorly on large scales. As a natural extension of previous work, in this article, we present a new unbiased estimator based on the Smith–Zaldarriaga (SZ) approach of E–B separation and the scalar QML approach to reconstruct the cross-correlation power spectrum, called the QML-SZ estimator. Our new estimator relies on the ability to construct scalar maps, which allows us to use a scalar QML estimator to obtain the cross-correlation power spectrum. By reducing the pixel number and algorithm complexity, the computational cost is nearly one order of magnitude smaller and the running time is nearly two orders of magnitude faster in the test situations.
Principal Component Analysis in the Modeling of Colors of Comae of Comets Hale-Bopp and Tabur
Authors: Betzler Alberto S. 
Published: June 2022

Abstract
The temporal variability of the colors of comae of comets has been reported for some decades. The color indices B-R of comets Hale-Bopp and Tabur were estimated with a variation of the model of Kolokolova et al., according to geometrical, populational, and compositional parameters of cometary dust. A principal component analysis of five model parameters points that the variation of these color indices is usually associated with changes in population or geometric parameters, and their extremes with a compositional variation of the dust grains.
Pre- and Post-entry, Descent and Landing Assessment of the Martian Atmosphere for the Mars 2020 Rover
Authors: Mischna Michael A. , Villar Gregory , Kass David M. , Dutta Soumyo , Rafkin Scot , Tyler Daniel , Barnes Jeffrey , Cantor Bruce , Lewis Stephen R. , Hinson David , Pla-García Jorge , Kleinböhl Armin , Karlgaard Chris 
Published: June 2022

Abstract
This review provides an analysis of activities undertaken by the Mars 2020 Council of Atmospheres (CoA) in support of the entry, descent, and landing (EDL) of the Mars 2020 rover Perseverance in Jezero crater, Mars. The activities of the CoA were designed to evaluate the safety of early-stage landing site candidates and, later, to constrain the range of plausible conditions expected at Jezero crater during the early northern spring season of EDL, following the successful blueprint of similar councils for prior landed Mars missions. The multiyear effort of the CoA involved using a combination of numerical modeling of the local Martian atmosphere with limited-domain mesoscale models and atmospheric reanalysis using data assimilation techniques, along with atmospheric observations from multiple orbiting assets, to generate an atmospheric “forecast” for the day of landing. Here we present an overview of these activities, focusing in greater detail on those elements that depart from prior CoA activities as performed for Mars Phoenix, Mars Science Laboratory, and the InSight lander. Following the successful landing of Perseverance on 2021 February 18, reconstruction and reassessment activities were performed and are presented here, comparing prelanding predictions with actual, as-flown conditions.
Effect of Ultrasonic and Diode Laser Irrigation Activation on Post-operative Pain and Microbial Reduction in Single Visit Endodontic Treatment of Necrotic Mandibular Molars
Authors: Elmallawany Ahmed , Hussein Yasser F. , Ali Magdy M. , Montasser Karim , Aly Yousra , Sharaf Nehal 
Published: June 2022

Aim: To clinically evaluate the effect of continuous ultrasonic and diode laser 810 wave length irrigation activation techniques on postoperative pain and bacterial reduction in single visit endodontic treatment of mandibular molars.
Material and methods: Forty patients requiring root canal treatment therapy for necrotic mandibular molars teeth were included in this study with age ranges between 20 and 45 years. In all cases, single visit endodontic treatment was carried out using Revo-S rotary file system in crown down sequence. NaOCl 2.5% irrigation solution was used during treatment. Patients were randomly and equally assigned into two groups according to irrigation technique. Group (1): conventional syringe irrigation and group (2): continuous ultrasonic irrigation. Each group was subdivided into two sub groups (n = 10); subgroup 1A (conventional syringe irrigation with no laser), subgroup 1B (conventional syringe irrigation with diode laser), subgroup 2A (continuous ultrasonic irrigation with no laser) and subgroup 2B (continuous ultrasonic irrigation with diode laser).
Postoperative pain evaluation was done using Visual Analogue Scale (VAS) at 6, 12, 24, 36, 48 hours and 7 days postoperatively. Microbiological detection of bacterial reduction was done by taking Samples (S1 and S2) for bacterial cultures. S1 after finishing access cavity and before mechanical preparation and S2 after finishing mechanical preparation and irrigation activation and before obturation. Samples were cultured on blood agar and determined as colony forming units (CFU/mL). Microbiological bacterial reduction was calculated accordingly. Statistical analyses were analyzed using the Mann-Whitney U test. The significance level was set at p < 0.05.
Results: In all sub groups, postoperative pain decreased by time in all time intervals but pain was significantly lower in subgroup (2B) (continuous ultrasonic irrigation with diode laser) than subgroup (1A) (conventional syringe irrigation with no laser) in all time interval. Microbiological results showed the highest bacterial reduction was in subgroup (2B) (continuous ultrasonic irrigation with diode laser) and least bacterial reduction was in subgroup (1A) (conventional syringe irrigation with no laser).
Conclusion: Using diode laser and continuous ultrasonic irrigation activation techniques as adjunctive methods showed improvement in postoperative pain records and enhanced bacterial reduction in root canal therapy.
Keywords: Continuous ultrasonic irrigation, diode laser 810, post-operative pain, bacterial reduction, single visit endodontic treatment.
Macrophytes distribution in the karstic river Rak and an assessment of the state of the aquatic system / Razporeditev makrofitov v kraški reki Rak in ocena stanja vodnega ekosistema
Authors: Kopitar Darja , Kravanja Marija , Trajbarič Aleksander , Germ Mateja 
Published: June 2022

The karst is a geographically and geologically highly dynamic area strongly dependent on water activity. This includes intermittent water bodies which have a specific impact on nearby environment. Sessile organisms such as plants have to adapt to extreme changes in water availability. Their presence, distribution and abundance can therefore serve as indicators of the ecological status of the water ecosystems. Using the modified Riparian, Channel, and Environmental (RCE) inventory method, we ranked the Rak River in the highest RCE quality classes. Based on the RMI (River Macrophyte Index), we classified the Rak River to good or very good ecological status. The good ecomorphological preservation of the Rak River probably also contributes to the presence of endangered plant species; among the 38 taxa listed, we detected the presence of eleven species included in Slovenian Red list of threatened pteridophytes and seed plants. At the time of our sampling, the species Zannichellia palustris was detected for the first time in this river. The high assessment of the preservation of the intermittent karst river Rak confirms the current good management and is important in the implementation of nature protection guidelines for the future.

IZVLEČEK
Kraški svet predstavljajo geografsko in geološko izjemno dinamična območja, ki so močno povezana z delovanjem vode. Presihajoča vodna telesa v kraškem svetu s svojim delovanjem močno vplivajo na okolje. V največji meri se morajo na velike spremembe dostopnosti vode prilagajati sesilni organizmi, kakršni so rastline. Njihova prisotnost, abundanca in razporeditev lahko služijo kot indikatorji stanja vodnih ekosistemov. S pomočjo prirejene metode RCE (ang. A Riparian, Channel, and Environmental Inventory) smo reko Rak uvrstili v najvišje RCE kakovostne razrede. Na osnovi indeksa RMI (ang. River Macrophyte Index) smo reko Rak uvrstili v dobro oz. zelo dobro ekološko stanje. Dobra ekomorfološka ohranjenost reke Rak verjetno botruje tudi pojavljanju ogroženih rastlinskih vrst; med 38 popisanimi taksoni smo zaznali prisotnost enajstih vrst, ki so uvrščene na Rdeči seznam ogroženih praprotnic in semenk. V času našega vzorčenja je bila v tej reki prvič zaznana vrsta Zannichellia palustris. Visoka ocena ohranjenosti presihajoče kraške reke Rak potrjuje dosedanje dobro upravljanje in je pomembna pri udejanjanju naravovarstvenih smernic za prihodnost.
Spectroscopic investigation complex formation of tungsten with 2, 6-dithiol-4-methylphenol in the presence of aminophenols
Authors: Kerim Avaz Kuliev  , Geysar S. Suleymanova  , Nazeni A. Novruzova  , Naiba N. Efendiyeva  
Published: June 2022

The mixed-ligand complexes of tungsten (VI) with 2, 6-dithiol-4-methylphenol (DTMP) in the presence of hydrophobic amines have been investigated by spectrophotometric method. The condition of complexing and extraction, physical-chemical and analytical characteristics of this complex have been found. From aminophenols 2(N, N-dime­thy­la­mino­me­thyl)-4-methylphenol (АP1), 2(N,N-dime­thy­­la­mi­nomethyl)-4-chlorphenol (АP2) and 2(N, N-di­me­thy­laminomethyl)-4-bromphenol (АP3), were used.. It has been found that mixed-ligand complex were formed in weakly acidic medium (pH 3.9 – 5.2). Maksimum of light absorp­tion observed at 476-480 nm. The calculated molar absorptivities (emax) belong to the interval (2.73-2.92)×104. The extraction-photometric methods of tungsten determination have been worked out. The influence of diverse ions on determination of tungsten has been studied. The proposed methods have been successfully applied to determination of tungsten in steel, soil and plant samples.
Establishment of the Biosorptive Properties of Ulva Lactuca Subjecting Eleusine Coracana (L) Gaertn to Heavy metal stress By Cobalt
Authors: Duraipandian M  , Sevugaperumal R  , Ganesh D  , Ramasubramanian V  
Published: June 2022

An efficient protocol for in vitro rapid multiplication of Coldenia procumbens L. has been developed. The shoot tip explants were cultured on MS basal medium supplemented with different concentrations of BAP and KIN. The two cytokinins are tested, BAP was found to develop higher number of shoots from the shoot tip explants when compared to KIN. higher number of shoots was produced from all the concentrations of BAP and KIN. The highest frequency of 100% shoot induction was observed on MS basal medium supplemented with 6 μM BAP and 10 μM KIN. The number of shoots observed on the MS basal medium supplemented with BAP obtained 14 as well as 11 in KIN. The data's are recorded after 30days of inoculation.
In vitro Shoot multiplication of Physalis minima L. - an important Medicinal Herb
Authors: Jahirhussain G  , Parvathi S  , Tamilselvan V  , Muniappan V  , Deepa K  , Veerappan R  
Published: June 2022

The present study was to develop an efficient protocol for shoot multiplication of Physalis minima L. Shoots were cultured using nodal segments from 20 days old field grown young plant. The nodal explants were cultured on MS medium supplemented with different concentrations of BAP and KIN. The two cytokinins tested, KIN was found to respond well in shoot multiplication and number of shoots from the nodal explants when compared to BAP. Large number of shoots was induced from all the concentrations of both BAP and KIN. BAP was found to develop in shoot multiplication and higher number of shoots from the nodal explants when compared to KIN. The highest frequency of 100% shoot induction was observed on MS basal medium supplemented with 8μM BAP and 10 μM KIN. Matured shoots are isolated and then transferred to the MS basal medium supplemented with different concentration of NAA and IBA for root induction. The higher number of roots were produced in 30 days on MS basal medium supplemented with 10 μM IBA and 6 μM NAA. The well rooted plantlets were isolated and transplanted to the paper cup for hardening and the well established plants were transferred to the field for acclimatization.
Evaluation of Active RT-PCR (NS1 Ag Assay) Compound for Dengue Haemorrhagic Fever (Aedes aegypti sp).
Authors: Lalitha S  , Pradeep C  , Pavithra R  
Published: June 2022

The global prevalence of dengue cases has increased in India. The increasingly widespread distribution and the rising incidence of dengue virus infections are related to increased distribution of Aedes aegypti, an increasingly urban population, and increasing air travel. Several countries show that the age of the reported dengue cases has increased from 5-12 years, to older children and young adults. Although shock and plasma leakage seem to be more prevalent as age decreases, the frequency of internal hemorrhage rises as age increases. Increase in liver enzymes found in both children and adults indicated liver involvement during dengue infections. Pre-existing liver diseases in adults such as chronic hepatitis, alcoholic cirrhosis, and hemoglobinopathies may aggravate the liver impairment in dengue infection. Fulminant hepatitis is a rare but well described problem in adult patients with dengue infection. Currently, no specific therapeutic agent exists for dengue. The early recognition of dengue infection, bleeding tendency, and signs of circulatory collapse would reduce mortality rates in adult patients with dengue infection.
Evaluation of Antioxidant Properties and Antimicrobial Activity of Garcinia cambogia Hort. Ex Boerl (Clusiaceae) fruit extracts.
Authors: Kokkaiah Irulandi  , Sethupandian Geetha  , Palanichamy Mehalingam  
Published: June 2022

Garcinia cambogia Hort. Ex Boerl (Clusiaceae) is a traditionally used medicinal plant claimed to possess antioxidant properties and antimicrobial activity. The present study was aimed to evaluate the in vitro antioxidant property and antimicrobial activity. The antioxidant property of the methanolic fruit extracts were evaluated using two methods. DPPH Radical Scavenging Assay, Total antioxidant phosphomolybdenum method and Total Reducing Capacity. The results revealed that free radical scavenging activity of methanolic fruits extracts of G. cambogia has significant radical scavenging ability on DPPH with IC50 value of 39. 45 µg/ml respectively. The positive control ascorbic acid showed the IC50 values of 32.42 µg/ml. The phytochemical screening showed the presence of Terpenoids, Tannins, Saponins, Phenols, Flavonoids and Steroids compounds. Methanol, Ethyl acetate and chloroform extracts of the plant was tested for antimicrobial activity against Gram positive bacteria such as Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Gram negative bacteria such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and a fungus Candida albicans using agar well plate method. The results obtained in the present study indicated that the fruit of G. cambogia showed the best antimicrobials activity against the C. albicans, S. aureus (G+) and K. pneumoniae (G-). Gentamicin is used as a positive control. In conclusion, the results indicate antimicrobial activity of the extract which could be further explored for purification of antioxidant compounds.
Synthesis, spectral characterization and DNA/Protein binding studies on Cobalt (II) complex containing Mixed ligand Ethylenediamine with 2-Hydroxy-1-Naphthaldehyde
Authors: Kadhiravan S  , Sivajiganesan S  , Periyathambi T  , Nanthakumar V  
Published: June 2022

New cobalt (II) complex has been synthesized and characterized by elemental analysis, UV-Vis, FT-IR and thermal analysis. Binding of this Co (II) complex with calf thymus DNA was investigated by UV-Visible absorption, fluorescence spectroscopy techniques. The intrinsic binding constants Kb of complex with CT-DNA obtained from UV-Vis absorption studies were 4.43 × 105M-1. Further, the in vitro cytotoxic effect of the complexes examined on cancerous cell line, such as human breast cancer cells (MCF-7).
Study of Effect of Substrate Temperature on Structure, Morphology and optical Properties of Spray Deposited Cu2ZnSnS4 Nano Thin films.
Authors: Ramesh Baloji Mahewar  , Limbraj Sopan Ravangave  
Published: June 2022

Cu2ZnSnS4 (CZTS) films for different substrate temperatures were deposited by using simple chemical spray technique. Analytical reagent Grade; Copper chloride (CuCl2), Zinc chloride (ZnCl2), Tin chloride (SnCl4.5H2O) and thiourea (SC(NH2)2) were used as Cu+, Zn+, and Sn+ and ion sources respectively. A set of five CZTS films was deposited using five different substrate temperatures (175, 200, 250, 275, and 300 ). The structure, Morphology, Elemental analysis and optical properties of these films were studied using X-ray diffratometer (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX) and UV-Visible spectroscopy techniques respectively. The XRD spectra showed that all films are polycrystalline and exhibit kesterite tetragonal crystal structure with preferential orientation along (112) direction. The crstallinity was found increased with substrate temperature. The calculated crystallite size was increased with increase in substrate temperature. The surface morphology of CZTS films was improved with increase in substrate temperature. The film sample deposited for 275 represent excellent spherical granules CZTS crystals of increasing size from 640 nm to 1.8 μm arranged in regular fashion with some void spaces. The purity of the composition was investigated using Elemental analysis of the deposited films. The optical band gap was estimated using Tauc plots. The band gap obtained was to be in the range of 1.4 to 1.6 eV.