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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.m.Weng P.Li X.F.Li h.Ai h.R.Pan Z.m.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of high Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(Thz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or Thz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or Thz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and Thz spectral ranges.

关键词： laser ultrashort photon

Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt

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Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa S ABO hATAB Yassin m AL-SODANY Kamal h ShALTOUT Soliman A hAROUN mohamed m EL-KhALAFY Botany and microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes morocco, mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the mediterranean and Irano-Turanian regions included in the holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic sp

关键词： endemism phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)

A statistical approach to enhance the productivity of Streptomyces baarensis mh-133 for bioactive compounds

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Synthetic and Systems Biotechnology 2024年第2期9卷 196-208页

作者： mohamed h.Kalaba Gamal m.El-Sherbiny Osama m.Darwesh Saad A.moghannem Botany and microbiology Department Faculty of Science(Boys)Al-Azhar UniversityCairo 11884Egypt Agricultural microbiology Department National Research CentreDokkiCairoEgypt

The goal of this study was to use statistical optimization to change the nutritional and environmental conditions so that Streptomyces baarensis mh-133 could make more active *** trials were used to screen for critical variables influencing productivity using the Placket-Burman Design *** mh-133 is significantly influenced by elicitation,yeast extract,inoculum size,and incubation period in terms of antibacterial activity.A total of 27 experimental trials with various combinations of these factors were used to carry out the response surface technique using the Box-Behnken *** analyses revealed that the model was highly significant(ph a lack-of-fit of 0.212 and a coefficient determination(R2)of ***,the model predicted that the response as inhibition zone diameter would reach a value of 27 *** optimal conditions,*** mh-133 produced 18.0 g of crude extract to each 35L and was purified with column *** active fraction exhibiting antibacterial activity was characterized using spectroscopic *** mIC and mBC values varied between 37.5 and 300μg/ml and 75 and 300μg/ml,*** conclusion,the biostatistical optimization of the active fraction critical variables,including environmental and nutritional conditions,enhances the production of bioactive molecules by Streptomyces species.

关键词： S.baarensis mh-133 Placket-Burman designBox-Behnken design ESKAPE Antibacterial activity

magnesium oxide(mgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： h.C.S.Perera V.Gurunanthanan Anoop Singh m.m.m.G.P.G.mantilaka G.Das Sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of Science University of PeradeniyaPeradeniyaSri Lanka Department of humanities and Sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for Global health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(mgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of mgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of mgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles,such as temperature,ph,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for mgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO ***,there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment heavy metals Dye separation Adsorption Synthesis methods

Effects of low molecular weight polysaccharide from Sargassum thunbergii against palmitic acid-induced intracellular lipid accumulation in 3T3-L1 adipocyte and hepG2 cells

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Food Science and human Wellness 2024年第4期13卷 2244-2252页

作者： hyo-Geun lee D.P.Nagahawatta m.J.m.S.Kurera Kyung-mo Song Yun-Sang Choi You-Jin Jeon min-Cheol Kang Department of marine Life Sciences Jeju National UniversityJeju 63243Republic of Korea Department of Biotechnology Faculty of Agriculture and Plantation ManagementWayamba University of Sri LankaMakanduraGonawila(NWP)60170Sri Lanka Research Group of Food Processing Korea Food Research Institute245Wanju 55365Republic of Korea

Low molecular weight polysaccharides can be isolated from Sargassum thunbergii(LmPST)and in vitro experiments were conducted to evaluate the inhibitory effects on *** natures of LmPST were attained from *** and appraised their LmPST on palmitic acid(PA)induced lipid accretion in hep G2,and 3T3-L1 *** treatment lessened lipid deposition and intracellular free fatty acid and triglyceride intensities in PA-treated above mentioned *** mechanistic study publicized that LmPST2 significantly suppressed adipogenesis and stimulated the PA-treated 3T3-L1 cells occupied in the lipolysis ***,in PA-treated hep G2 cells,the free fatty acid oxidation was significantly increased by *** these constructive properties of LmPST2 from ***,is a potential candidate for diminishing the intracellular lipids,and for a therapeutic agent in those conditions.

关键词： Sargassum thunbergii Low molecular weight polysaccharide Lipid accumulation Obesity Liver steatosis

Atomically Adjustable Rhodium Catalyst Synthesis with Outstanding mass Activity via Surface-Li mi ted Cation Exchange

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Energy & Environmental materials 2024年第2期7卷 83-92页

作者： hak hyeon lee Dong Su Kim Swagotom Sarker Ji hoon Choi ho Seong lee hyung Koun Cho Department of Advanced materials Science&Engineering Sungkyunkwan University2066Seobu-roJangan-guSuwon-siGyeonggi-doSeoul 16419Korea Department of Advanced materials Science&Engineering Kyungpook National University80Daehak-roBuk-guDaegu 41566Korea

Rh has been widely studied as a catalyst for the promising hydrazine oxidation reaction that can replace oxygen evolution reactions for boosting hydrogen production from hydrazine-containing *** Rh being expensive,only a few studies have examined its electrocatalytic mass ***,surface-limited cation exchange and electrochemical activation processes are designed to remarkably enhance the mass activity of *** atoms were readily replaced at the Ni sites on the surface of NiOOh electrodes by cation exchange,and the resulting RhOOh compounds were activated by the electrochemical reduction *** cation exchange-derived Rh catalysts exhibited particle sizes not exceeding 2 nm without agglomeration,indicating a decrease in the number of inactive inner Rh ***,an improved mass activity of 30 A mg_(Rh)^(-1)was achieved at 0.4 V versus reversible hydrogen ***,the two-electrode system employing the same CE-derived Rh electrodes achieved overall hydrazine splitting over 36 h at a stable low *** proposed surface-limited CE process is an effective method for reducing inactive atoms of expensive noble metal catalysts.

关键词： cation exchange synthesis electrochemical metallization hydrazine oxidation reaction mass activity rhodium catalyst

Dynamical control of nanoscale light-matter interactions in low-dimensional quantum materials

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Light(Science & Applications) 2024年第2期13卷 236-253页

作者： Yeonjeong Koo Taeyoung moon mingu Kang huitae Joo Changjoo lee hyeongwoo lee Vasily Kravtsov Kyoung-Duck Park Department of Physics Pohang University of Science and Technology(POSTECH)Pohang37673Republic of Korea School of Physics and Engineering ITMO UniversitySaint Petersburg197101Russia

Tip-enhanced nano-spectroscopy and-imaging have significantly advanced our understanding of low-dimensional quantum materials and their interactions with light,providing a rich insight into the underlying physics at their natural length ***,various functionalities of the plasmonic tip expand the capabilities of the nanoscopy,enabling dynamic manipulation of light-matter interactions at the *** this review,we focus on a new paradigm of the nanoscopy,shifting from the conventional role of imaging and spectroscopy to the dynamical control approach of the tip-induced light-matter *** present three different approaches of tip-induced control of light-matter interactions,such as cavity-gap control,pressure control,and near-field polarization ***,we discuss the nanoscale modifications of radiative emissions for various emitters from weak to strong coupling regime,achieved by the precise engineering of the ***,we introduce recent works on light-matter interactions controlled by tip-pressure and near-field polarization,especially tunability of the bandgap,crystal structure,photoluminescence quantum yield,exciton density,and energy transfer in a wide range of quantum *** envision that this comprehensive review not only contributes to a deeper understanding of the physics of nanoscale light-matter interactions but also offers a valuable resource to nanophotonics,plasmonics,and materials science for future technological advancements.

关键词： quantum precise shifting

Improving the Transmission Security of Vein Images Using a Bezier Curve and Long Short-Term memory

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Computers, materials & Continua 2024年第6期79卷 4825-4844页

作者： Ahmed h.Alhadethi Ikram Smaoui Ahmed Fakhfakh Saad m.Darwish Computer Science and School of Electronics and Telecommunications University of SfaxSfax3029Tunisia LETI Laboratory University of SfaxSfax3029Tunisia Digital Research Center of Sfax Technopark of SfaxSfax3029Tunisia Department of Information Technology Institute of Graduate Studies and ResearchAlexandria UniversityAlexandriaEgypt

The act of transmitting photos via the Internet has become a routine and significant *** the security measures to safeguard these images from counterfeiting and modifications is a critical domain that can still be further *** study presents a system that employs a range of approaches and algorithms to ensure the security of transmitted venous *** main goal of this work is to create a very effective system for compressing individual biometrics in order to improve the overall accuracy and security of digital photographs by means of image *** paper introduces a content-based image authentication mechanism that is suitable for usage across an untrusted network and resistant to data loss during *** employing scale attributes and a key-dependent parametric Long Short-Term memory(LSTm),it is feasible to improve the resilience of digital signatures against image deterioration and strengthen their security against malicious ***,the successful implementation of transmitting biometric data in a compressed format over a wireless network has been *** applications involving the transmission and sharing of images across a *** suggested technique utilizes the scalability of a structural digital signature to attain a satisfactory equilibrium between security and picture *** effective adaptive compression strategy was created to lengthen the overall lifetime of the network by sharing the processing of *** scheme ensures a large reduction in computational and energy requirements while minimizing image quality *** approach employs multi-scale characteristics to improve the resistance of signatures against image *** proposed system attained a Gaussian noise value of 98%and a rotation accuracy surpassing 99%.

关键词： Image transmission image compression text hiding Bezier curve histogram of Oriented Gradients(hOG) LSTm image enhancement Gaussian noise rotation

Tilted global solar irradiance in Bahrain:an experimental study

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Clean Energy 2024年第2期8卷 27-34页

作者： N.Vasilikos C.Georgantopoulou h.Alajaimi S.h.Almajed m.Ahmed D.mathioulakis School of mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,Kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).more importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from may to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries