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Probing turbulence in galaxies with fast radio burst scintillation

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Science China(Physics,mechanics & Astronomy) 2024年第1期67卷 177-178页

作者： James m.Cordes Department of Astronomy the Cornell Center for Astrophysics and Planetary ScienceCornell UniversityIthaca NY 14853USA

Interstellar scintillation(ISS)is a well-known phenomenon observed from pulsars in the milky *** comprises intensity variations *** and frequency caused by constructive and destructive interference from multipath propagation,which is due to diffraction from fluctuations in electron density in the interstellar medium(ISm)on scales as small as~100 *** density fluctuations appear to be part of a turbulence process combined with discrete structures in electron density from other astrophysical processes;together these fluctuations extend to scales of pc or larger.

关键词： scales galaxies turbulence

Exploring the Prevalence and Contributing Factors of Depression among Sickle Cell Anemia Patients in Saudi Arabia’s Jazan Region

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International Journal of mental health Promotion 2024年第5期26卷 351-359页

作者： Abdullah A.Alharbi Ahmad Y.Alqassim mohammed A.muaddi Najat h.Aldubayyan Rana I.Abuhadi Futon A.Akoor Sarah J.mobarki Imtenan A.Oberi Ghaidaa h.Alharbi Yara Ajeebi Adnan m.Alkhayat hafiz malhan mohammed Bakkar Anwar m.makeen Family and Community medicine Department Faculty of MedicineJazan UniversityJazan45142Saudi Arabia Laboratory Department King Fahd Central HospitalMinistry of HealthJazan45142Saudi Arabia Internal medicine Department Prince Mohammad bin Nasser HospitalMinistry of HealthJazan45142Saudi Arabia hematology Department King AbdulAziz Medical City for National GuardRiyadh11426Saudi Arabia

Sickle Cell Anemia(SCA)is a prevalent genetic condition in Saudi Arabia,particularly in the Jazan *** study’s purpose was to assess the prevalence of de-pression among individuals with SCA in this area and to identify the factors associated with this *** study involved 391 adult participants,all patients in the hematology center of Prince mohammed bin Nasser hospital(PmNh).Data was collected through an anonymous interview questionnaire–the Arabic version of the Patient health Questionnaire-9(PhQ-9)–between march–may *** questionnaire covered socio-demographic information and variables related to the participant’s SCA history,such as pain levels,frequency of pain,hospitalization duration,and frequency of blood *** variables underwent Chi-square and One-way ANOVA testing,followed by multivariate *** study found a 42%prevalence of depression among the SCA *** significantly linked with heightened depression levels included being widowed or divorced,experiencing frequent and severe pain,and longer duration of hospital *** educational level of at least a bachelor’s degree was also a significant *** study reveals a high prevalence of depression among SCA patients in the Jazan *** underscores the need for policymakers to educate both physicians and patients about the importance of mental health in SCA *** study also highlights the need for more research into the specific causes and effects of depressive symptoms in SCA patients to inform the creation of effective management plans.

关键词： Sickle cell anemia prevalence depression public health policy Jazan region Saudi Arabia

Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECh 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz C.C.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

Scalable orthogonal delay-division multiplexed OEO artificial neural network trained for TI-ADC equalization

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Photonics Research 2024年第1期12卷 85-105页

作者： ANDREA ZAZZI ARKA DIPTA DAS LUKAS hüSSEN RENATO NEGRA JEREmY WITZENS Institute of Integrated Photonics RWTH Aachen University52074 AachenGermany Chair of high-Frequency Electronics RWTH Aachen University52074 AachenGermany

We propose a new signaling scheme for on-chip optical-electrical-optical artificial neural networks that utilizes orthogonal delay-division multiplexing and pilot-tone-based self-homodyne *** scheme offers a more efficient scaling of the optical power budget with increasing network *** simulations,based on220 nm silicon-on-insulator silicon photonics technology,suggest that the network can support 31×31 neurons,with 961 links and freely programmable weights,using a single 500 m W optical comb and a signal-to-noise ratio of 21.3 d B per ***,it features a low sensitivity to temperature fluctuations,ensuring that it can be operated outside of a laboratory *** demonstrate the network’s effectiveness in nonlinear equalization tasks by training it to equalize a time-interleaved analog-to-digital converter(ADC)architecture,achieving an effective number of bits over 4 over the entire 75 Ghz ADC *** anticipate that this network architecture will enable broadband and low latency nonlinear signal processing in practical settings such as ultra-broadband data converters and real-time control systems.

关键词： network delay artificial

Spinal dural arteriovenous fistula:a comprehensive review of the history,classification systems,management,and prognosis

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Chinese Neurosurgical Journal 2024年第1期10卷 48-56页

作者： Ali Alkhaibary Ahoud Alharbi Nada Alnefaie hajar Alammar Alshaymaa m.Arishy Noor Alghanim Yazeed m.Aldhfyan Arwa Albaiahy Yahya h.Khormi Wael Alshaya Saad AlQahatani Ahmed Aloraidi Ahmed Alkhani Sami Khairy College of medicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International medical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Department of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of medicine Jazan UniversityJazanSaudi Arabia Department of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Department of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the majority of spinal vascular *** are typically located in the thoracolumbar region and are diagnosed in the middle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact development remains ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura mater,where the blood from the radiculomeningeal artery and radicular vein *** history,there have been multiple classification systems of spinal arteriovenous shunts since *** were mainly based on the evolution of diagnostic studies as well as the treatment of these *** classification systems have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological manifestations,due to venous congestion,tend to be insidious as well as *** include sensory deficits,such as paresthesia,bilateral and/or unilateral radicular pain affecting the lower limbs,and gait *** dural arteriovenous fistulas can be suspected on magnetic resonance imaging/magnetic resonance angiography and confirmed by digital subtraction angiography(DSA).The management includes surgery,endovascular therapy,and in selected cases,*** treatment goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of symptoms as well as the clinical condition prior to *** present article comprehensively reviews the pathophysiology,changes in classification systems,natural history,clinical manifestations,radiological features,management,and prognosis.

关键词： Connection Endovascular myelopathy Vascular

Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： yasir Abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 hz-3 mhz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

Ab initio valence-space in-medium similarity renormalization group calculations for neutron-rich P,Cl,and K isotopes

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Chinese Physics C 2024年第7期48卷 181-190页

作者：谢萌冉沈留媛李健国李红蕙袁琪左维 Institute of modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Neutron-rich P,Cl,and K isotopes,particularly those with neutron numbers of approximately N=28,have attracted extensive experimental and theoretical *** utilize the ab initio valence-space in-medium similarity renormalization group approach,based on chiral nucleon-nucleon and three-nucleon forces,to investigate the exotic properties of these *** calculations of the low-lying spectra are performed.A key finding is the level inversion between 3/2^(+)_(1)and 1/2^(+)_(1)states in odd-A isotopes,attributed to the inversion ofπ0xod3/2 andπls1/2 single-particle *** ab initio calculations,which incorporate the three-nucleon forces,correlate closely with existing experimental *** calculations of effective proton single-particle energies provide deeper insights into the shell evolution for Z=14 and 16 *** results indicate that the three-body force plays important roles in the shell evolution for Z=14 and 16 sub-shells with neutron numbers ranging from 20 to ***,systematic ab initio calculations are conducted for the low-lying spectra of odd-odd *** results correspond with experimental data and provide new insights for future research into these isotopes up to and beyond the drip line.

关键词： ab initio calculations shell evolution low-lying spectra

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen huded m Suresh R Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： N.m.Basfer hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： Nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy