bluuebunny/crossref_metadata_2025 huggingface dataset:
Intermolecular proton transfer from flavonol to human serum albumin triggers a red-shifted ratiometric fluorescence response
Authors: Xu Zhongyong , Zhang Mingyuan , Chen Zihao , Zhao Yutian , Wang Lei , Chen Xiaoqiang , Liu Bin , Peng Xiaojun
Published: April 2023

Intermolecular proton transfer from a flavonol-based probe to the arginine (Arg222) in human serum albumin triggers a red-shifted ratiometric fluorescence response, which can be applied in the point-to-care diagnosis of hypoalbuminemia.
Nonclassical crystal growth and growth rate hysteresis observed during the growth of curcumin in impure solutions
Authors: Vasanth Kumar K. , Gadipelli Srinivas , Ramisetty Kiran A. , Heffernan Claire , Stewart Andrew A. , Ranade Vivek , Howard Chris , Brett Dan
Published: April 2023

Partially dissolved crystals of curcumin grow faster and exhibit an accelerated growth rate hysteresis.
Methylthio-functionalized UiO-66 to promote the electron–hole separation of ZnIn2S4for boosting hydrogen evolution under visible light illumination
Authors: Li Xiang , Li Qiulin , Shang Wenjing , Lou Yongbing , Chen Jinxi
Published: April 2023

A facile and effective hydrothermal method was developed to fabricate a UiOSC/ZIS composite. Its significantly improved hydrogen evolution activity and stability could be attributed to the suppression of the recombination of carriers and holes.
Ni(ii) and Zn(ii)-metallogel-based anti-bacterial scaffolds for fabricating light-responsive junction-type semiconducting diodes with non-ohmic conduction mechanism
Authors: Lepcha Gerald , Pal Baishakhi , Majumdar Santanu , Ahmed Kazi Tawsif , Pal Indrajit , Biswas Swadesh Ranjan , Ray Partha Pratim , Dey Biswajit
Published: April 2023

Sebacic acid-based thixotropic supramolecular Ni(ii)/Zn(ii)-metallogels are utilized for inhibiting poisonous bacteria and offering light-responsive semiconducting diodes with non-ohmic conduction mechanism.
Evaluating the effect of two-dimensional molecular layout on DNA origami-based transporters
Authors: Fukumoto Kodai , Miyazono Yuya , Ueda Takuya , Harada Yoshie , Tadakuma Hisashi
Published: April 2023

Single-molecule fluorescence imaging of DNA origami-based transporters showed shorter run lengths in dence layouts of kinesin motors.
High-compact MXene-based coatings by controllable interfacial structures
Authors: Ding Jiheng , Wang Hao , Zhao Hongran , Miah Mohammad Raza , Wang Jinggang , Zhu Jin
Published: April 2023

Titanium carbide (Ti3C2Tx) MXenes have been regarded as important functional fillers of organic coatings for anticorrosion.
Comparison of the peroxidase activities of iron oxide nanozyme with DNAzyme and horseradish peroxidase
Authors: Lu Chang , Zandieh Mohamad , Zheng Jinkai , Liu Juewen
Published: April 2023

A systematic comparison of three catalysts with peroxidase and peroxidase-like activities revealed the trend of activity, stability and the effect of buffer and pH for the oxidation of TMB.
Technical, economic, and environmental potential of glycerol hydrogenolysis: a roadmap towards sustainable green chemistry future
Authors: Minh Loy Adrian Chun , Ng Wei Lin , Samudrala Shanthi Priya , Bhattacharya Sankar
Published: April 2023

The dilemma of fossil fuel use, political versatility, and global climate change have driven motivation that has led to growing interest in developing and implementing renewable energy and green chemical technologies.
Application of deep learning to support peak picking during non-target high resolution mass spectrometry workflows in environmental research
Authors: Mottershead Kate , Miller Thomas H.
Published: April 2023

A CNN was developed to classify extracted features from nontarget mass spectrometry workflows. The CNN accuracy ranged from 85% to 100%. These tools will be important in data-driven research enabling rapid processing of large volume and complex datasets.
Exploring microRNAs in craniofacial regenerative medicine
Authors: Su Dan , Swearson Samuel , Krongbaramee Tadkamol , Sun Hongli , Hong Liu , Amendt Brad A.
Published: April 2023

microRNAs (miRs) have been reported over the decades as important regulators in bone development and bone regeneration. They play important roles in maintaining the stem cell signature as well as regulating stem cell fate decisions. Thus, delivering miRs and miR inhibitors to the defect site is a potential treatment towards craniofacial bone defects. However, there are challenges in translation of basic research to clinics, including the efficiency, specificity, and efficacy of miR manipulation methods and the safety of miR delivery systems. In this review, we will compare miR oligonucleotides, mimics and antagomirs as therapeutic reagents to treat disease and regenerate tissues. Newer technology will be discussed as well as the efficiency and efficacy of using these technologies to express or inhibit miRs in treating and repairing oral tissues. Delivery of these molecules using extracellular vesicles and nanoparticles can achieve different results and depending on their composition will elicit specific effects. We will highlight the specificity, toxicity, stability, and effectiveness of several miR systems in regenerative medicine.
On the performance of non‐contiguous carrier aggregation in presence of subspectral errors
Authors: Zhang Jing , Yang Chao , Liu Zhenghong , Chen Zhe , Zheng Lin
Published: April 2023

Carrier aggregation can not only increase communication bandwidth, but also improve spectrum efficiency and communication security. Considering the non‐contiguous multi‐subspectrum aggregation for the spectrum division transmission of arbitrary signal, the paper analyzes the performance impact on the demodulation of aggregated signal in the presence of subspectral amplitude and phase errors in receiver. The theoretical bit‐error rates (BER) of quaternary phase‐shift keying and M‐ary phase‐shift keying are derived to clarify the subspectrum synchronization accuracy requirements in non‐contiguous carrier aggregation. In addition, two adaptive equalizers requiring no pilot overhead are introduced to correct the distortion of aggregated signal caused by the subspectral errors. Both algorithms need no estimation of synchronization error but also have the tracking capability of phase error even with subspectral carrier error. Simulation results show the reliability of the theoretical BER performance and the excellent performance of the equalization algorithms.
An approximating pseudospectral method with state‐dependent coefficient optimization for nonlinear optimal control problem
Authors: Sun Jianfeng , Chen Xuesong
Published: April 2023

The approximating sequence Riccati equation method is an efficient approach for solving the nonlinear optimal control problems, but its neglect of nonlinear dynamics and necessary optimality condition makes the control law difficult to satisfy the optimality. In this paper, an approximating pseudospectral method with state‐dependent coefficient optimization algorithm is proposed to solve this defect. By introducing the approximating pseudospectral method, the original nonlinear problem is transformed into a sequence of linear subproblems, which preserves the nonlinearity of solution. Then a state‐dependent coefficient optimization algorithm based on the gradient projection technique is proposed, which ensures the optimality of the control law. A double‐layer optimization structure is designed to facilitate the coordination between the approximating method and the optimization algorithm. Theoretical analysis proves the convergence of the proposed method. Comparative case studies illustrate the effectiveness in reducing the performance index and ensuring the optimality of the control law.
Hydrogen‐powered smart grid resilience
Authors: Han Jiayi , Wang Jianxiao , He Zhihao , An Qi , Song Yiyang , Mujeeb Asad , Tan Chin‐Woo , Gao Feng
Published: April 2023

With an increasing frequency of natural disasters and security attacks, the safe and stable operation of smart grid has been challenged unprecedently. To reduce the economic loss and social impact caused by power outage accidents, it is urgent to develop and improve the smart grid technology, and strengthen the disaster resistance and recovery capability of smart grids when faced with extreme events. As an efficient and flexible secondary energy source, hydrogen is crucial in improving the resilience of smart grid and supporting energy security. To further promote the deep integration of hydrogen systems and smart grid and improve the energy system resilience, the resilience of smart grids supported by hydrogen is assessed here. First, a technical framework of hydrogen‐powered smart grid resilience is established, and the value of hydrogen‐powered smart grid resilience is analysed considering different time frames (before, during and after an extreme event) of smart grids facing extreme events. Then, hydrogen‐powered smart grid resilience is investigated from perspectives of pre‐prevention regulation, in‐process correction regulation, and post‐recovery regulation. Finally, future direction for hydrogen‐powered smart grid resilience is investigated and related policy suggestions are provided.
A Gaussian process cross-correlation approach to time-delay estimation in active galactic nuclei
Authors: Pozo Nuñez F. , Gianniotis N. , Polsterer K. L.
Published: April 2023

Context. We present a probabilistic cross-correlation approach to estimate time delays in the context of reverberation mapping (RM) of active galactic nuclei (AGN).

Aims. We reformulate the traditional interpolated cross-correlation method as a statistically principled model that delivers a posterior distribution for the delay.

Methods. The method employs Gaussian processes as a model for observed AGN light curves. We describe the mathematical formalism and demonstrate the new approach using both simulated light curves and available RM observations.

Results. The proposed method delivers a posterior distribution for the delay that accounts for observational noise and the non-uniform sampling of the light curves. This feature allows us to fully quantify the uncertainty on the delay and propagate it to subsequent calculations of dependant physical quantities, such as black hole masses. The method delivers out-of-sample predictions, which enables us to subject it to model selection, and can calculate the joint posterior delay for more than two light curves.

Conclusions. Because of the numerous advantages of our reformulation and the simplicity of its application, we anticipate that our method will find favour not only in the specialised community of RM, but also in all fields where cross-correlation analysis is performed. We provide the algorithms and examples of their application as part of our Julia GPCC package.
Survey of Orion Disks with ALMA (SODA)
Authors: van Terwisga S. E. , Hacar A.
Published: April 2023

Context. External far-ultraviolet (FUV) irradiation of protoplanetary disks has an important impact on their evolution and ability to form planets. However, nearby (< 300 pc) star-forming regions lack sufficiently massive young stars, while the Trapezium cluster and NGC 2024 have complicated star-formation histories and their O-type stars’ intense radiation fields (> 104 G0) destroy disks too quickly to study this process in detail.

Aims. We study disk mass loss driven by intermediate (10 − 1000 G0) FUV radiation fields in L1641 and L1647, where it is driven by more common A0- and B-type stars.

Methods. Using the large (N = 873) sample size offered by the Survey of Orion Disks with ALMA (SODA), we searched for trends in the median disk dust mass with FUV field strength across the region as a whole and in two separate regions containing a large number of irradiated disks.

Results. For radiation fields between 1 − 100 G0, the median disk mass in the most irradiated disks drops by a factor ∼2 over the lifetime of the region, while the 95th percentile of disk masses drops by a factor 4 over this range. This effect is present in multiple populations of stars, and localized in space, to within 2 pc of ionizing stars. We fitted an empirical irradiation – disk mass relation for the first time: Mdust,median = −1.3−0.13+0.14 log10(FFUV/G0) + 5.2−0.19+0.18.

Conclusions. This work demonstrates that even intermediate FUV radiation fields have a significant impact on the evolution of protoplanetary disks.
Effects of graphite nodule count on microstructural homogeneity of austempered ductile iron (ADI)
Authors: Hu Zhitao , Wang Xin , Du Yuzhou , Liu Chen , Gao Zhijie , Li Jiaze , Jiang Bailing
Published: April 2023

The microstructural homogeneity of austempered ductile iron (ADI) with different graphite counts was evaluated by microstructural observations and hardness measurement. ADI was composed of spheroidal graphite, ausferrite, and stabilized austenite. Microstructural observation and microhardness evaluation indicated that graphite nodule counts affected the microstructure significantly, in a sense that the microstructure was more homogeneous for samples with higher graphite counts. More graphite nodules provided more positions for ferrite nucleation and gave rise to a fine ausferrite microstructure. However, for samples with fewer graphite nodules, the diffusion of carbon atoms in austenite far away from graphite was inhibited, which stabilized the austenite and gave rise to the existence of large-size blocky austenite. Consequently, ADI with high graphite nodule count exhibited superior ductility. This study suggested that more graphite nodule is preferred in ADI to obtain a more homogeneous microstructure.
Biomarker in der Onkologie
Authors: Bubenzer Rainer H.
Published: April 2023

Die im Rahmen von Tumorerkrankungen in der Humangenetik und der Pathologie durchgeführte molekulargenetische Diagnostik ist eine wesentliche Voraussetzung für die moderne, individualisierte Präzisionsmedizin und gewinnt daher für die Tumortherapie und -prävention zunehmend an Bedeutung. Allerdings, betonte Prof. Brigitte Schlegelberger, Hannover, beim letzten Deutschen Krebskongress, kann eine alleinige Tumorsequenzierung pathogene Keimbahnvarianten – und damit ein erbliches Tumorrisikosyndrom (TRS) – weder sicher nachweisen noch ausschließen, wie auch die Ende 2021 publizierte S1-Leitlinie zu diesem Thema ausführt. Deshalb plädierte sie dafür, „Tumor- und Keimbahnanalyse nicht getrennt, sondern zusammen zu sehen und – wann immer bei onkologischen Patienten möglich – auch parallel durchzuführen“.
Magen- und Ösophaguskarzinom
Authors: Schmale Ine
Published: April 2023

Die Immuntherapie in Kombination mit einer Chemotherapie ist der neue Erstlinienstandard für Patient*innen mit Tumoren des Magens, des gastroösophagealen Übergangs und des Ösophagus. Beim Gastrointestinal Cancers Symposium der American Society of Clinical Oncology (ASCO GI) präsentierte Ergebnisse bestätigen die überlegene Wirksamkeit dieser Strategie und geben Hinweise für die Einordnung etablierter Therapieoptionen.
Yttrium-Catalyzed Regioselective Aminolysis of 2,3-Epoxy Esters and Amides
Authors: Wang Chuan , Yao Hongqing
Published: April 2023

Herein, an yttrium-catalyzed regioselective ring-opening reaction of 2,3-epoxy esters and amides with amines as nucleophiles is presented. This method features high regiocontrol, an enantiospecific SN2 reaction pathway, a broad substrate scope, and mild reaction conditions, furnishing a wide range of α-hydroxy β-amino esters and amides in regioisomerically pure forms. Notably, the selective nucleophilic attack to the C-3 position is controlled by the directing effect of the carbonyl group of the substrates.
Overweight Impairs Postural Control of Female Night Workers
Authors: Narciso Fernanda Veruska , Dâmaso Ana R. , Barela Jose A. , Carvalho Adriana N. S. , Ruiz Francieli , de Queiroz Sandra Souza , Lemos Vanessa Silva , de-Andrade Andre Gustavo P. , Tufik Sergio , De-Mello Marco Túlio
Published: April 2023

Objectives To verify the relationships between sleep duration (Total Sleep Time – TST) and postural control of female night workers before and after shift. As well as, to verify if there is an influence of the body mass index (BMI) on the postural control of these female workers before and after shift.

Methods A total of 14 female night workers (mean age: 35.0 ± 7.7 years) were evaluated. An actigraph was placed on the wrist to evaluate the sleep-wake cycle. The body mass and height were measured, and BMI was calculated. Postural control was evaluated by means of a force platform, with eyes opened and eyes closed before and after the 12-hour workday.

Results There was an effect of the BMI on the velocity and the center of pressure path with eyes opened before (t = 2.55, p = 0.02) and after (t = 4.10, p < 0.01) night work. The BMI impaired the velocity and the center of pressure path with eyes closed before (t = 3.05, p = 0.01; t = 3.04, p = 0.01) and after (t = 2.95, p = 0.01; t = 2.94, p = 0.01) night work. Furthermore, high BMI is associated with female workers' postural sway (p < 0.05).

Conclusion Therefore, high BMI impairs the postural control of female night workers, indicating postural instability before and after night work.
Similar soil drying-induced stomatal closure in soybean genotypes varying in abscisic acid accumulation and stomatal sensitivity to abscisic acid
Authors: Castro-Valdecantos Pedro , Puértolas Jaime , Dodd Ian C.
Published: April 2023

Different soybean cultivars (Williams 82, Union, Jindou 21, Long Huang 1, Long Huang 2) were exposed to drying soil, to investigate whether endogenous abscisic acid (ABA) concentrations and leaf water relations regulated stomatal behaviour. We measured ABA concentrations in xylem and tissue of the first and second trifoliate leaves respectively; stomatal conductance (gs) and leaf water potential (Ψleaf) in both leaves; and water content in soil. Cultivar variation in leaf area and gs caused different rates of soil drying, but gs and Ψleaf declined similarly with soil drying in all cultivars. Variation in leaf xylem ABA concentration better explained stomatal responses than foliar ABA concentration in some cultivars, and was highly correlated with stomatal conductance. Xylem ABA concentration in well-watered soil was highest in Union, and in drying soil was lowest in Jindou 21 and Long Huang 2, although the latter had the highest foliar ABA concentrations. Jindou 21 accumulated lower xylem ABA concentrations than other cultivars as soil moisture or Ψleaf decreased, but its stomatal sensitivity to xylem ABA was greater. Because cultivars varied in both ABA accumulation and stomatal sensitivity to ABA, but had similar stomatal sensitivity to Ψleaf, leaf water relations seem more important in regulating stomatal closure of soybean.
First evidence of multiple paternity and hybridisation in Australian sawsharks
Authors: Nevatte Ryan J. , Williamson Jane E. , Gillings Michael R.
Published: April 2023

Context Knowledge of sawshark reproductive biology is limited to general parameters such as reproductive mode and litter size. The mating system is currently unknown. Aim To test for multiple paternity in the common (Pristiophorus cirratus) and southern (Pristiophorus nudipinnis) sawshark and investigate the occurrence of hybridisation between these two species. Methods Pups from a single litter of each species and an adult P. nudipinnis displaying mismatches in its morphology and mitochondrial DNA were genotyped with nuclear single-nucleotide polymorphisms (SNPs). Multiple paternity was assessed using pairwise relatedness and sibship analysis, and hybridisation was examined using three approaches (principal-component analysis, admixture analysis and clustering with NewHybrids). Key results Multiple paternity was detected in both species, with two males siring the seven-pup litter in P. cirratus and two males siring the two-pup litter in P. nudipinnis. Hybridisation between the two species was also confirmed, with the mismatched adult identified as a first-generation hybrid. Conclusions The mating system of sawsharks involves polyandry, and hybridisation between the two co-occurring Australian species is possible. Implications These results provide new information on sawshark reproductive biology and highlight the need for combined use of mitochondrial and nuclear markers in future genetic studies involving these species.
A backpack-based myeloid cell therapy for multiple sclerosis
Authors: Kapate Neha , Dunne Michael , Kumbhojkar Ninad , Prakash Supriya , Wang Lily Li-Wen , Graveline Amanda , Park Kyung Soo , Chandran Suja Vineeth , Goyal Juhee , Clegg John R. , Mitragotri Samir
Published: April 2023

Multiple sclerosis (MS) is an incurable autoimmune disease and is currently treated by systemic immunosuppressants with off-target side effects. Although aberrant myeloid function is often observed in MS plaques in the central nervous system (CNS), the role of myeloid cells in therapeutic intervention is currently overlooked. Here, we developed a myeloid cell-based strategy to reduce the disease burden in experimental autoimmune encephalomyelitis (EAE), a mouse model of progressive MS. We developed monocyte-adhered microparticles (“backpacks”) for activating myeloid cell phenotype to an anti-inflammatory state through localized interleukin-4 and dexamethasone signals. We demonstrate that backpack-laden monocytes infiltrated into the inflamed CNS and modulated both the local and systemic immune responses. Within the CNS, backpack-carrying monocytes regulated both the infiltrating and tissue-resident myeloid cell compartments in the spinal cord for functions related to antigen presentation and reactive species production. Treatment with backpack-monocytes also decreased the level of systemic pro-inflammatory cytokines. Additionally, backpack-laden monocytes induced modulatory effects on T
H
1 and T
H
17 populations in the spinal cord and blood, demonstrating cross talk between the myeloid and lymphoid arms of disease. Backpack-carrying monocytes conferred therapeutic benefit in EAE mice, as quantified by improved motor function. The use of backpack-laden monocytes offers an antigen-free, biomaterial-based approach to precisely tune cell phenotype in vivo, demonstrating the utility of myeloid cells as a therapeutic modality and target.
Controllable and enormous spin splitting in antiferromagnetic MnPSe3 through interfacial coupling with Janus MoSSe
Authors: Li Yingqiu , Zhang Zongnan , Wu Xuefeng , Wu Yaping , Li Xu , Zhang Chunmiao , Cao Yiyan , Wu Zhiming , Kang Junyong
Published: April 2023

The manipulation of spin and valley degree of freedom in two-dimensional materials is desirable for emerging applications in next-generation electronics. Here, we report a regulation of the spin splitting in monolayer antiferromagnetic MnPSe3 through stacking van der Waals (vdW) heterostructures with transition-metal dichalcogenides (TMDs). Different TMDs including Janus MoSSe, MoSe2, and MoS2 are engaged and the spin and valley dependences on stacking configurations, interfacial atoms, and interlayer spacings are comprehensively investigated based on first-principles calculations. The results show that spin degeneracy of MnPSe3 can be lifted through the interfacial interaction in the vdW heterostructures. Compared with the MnPSe3 interfacing with traditional TMDs (MoSe2 and MoS2), those with Janus TMDs (MoSSe or MoSeS) have larger spin splitting. A maximal spin splitting of 50.8 meV at valence band maximum is achieved in MoSSe/MnPSe3 heterostructure, and such splitting is further enhanced to 243.0 meV when the interlayer spacing is reduced to 2.9 Å. It is found that the different hybridizations between the d-orbitals of the two inequivalent Mn atoms in MnPSe3 and the above TMDs lead to the occurrence of net magnetic moments, and thus induce spin splitting. This work paves a novel way to modify the spin-valley properties of two-dimensional semiconductors.
Giant tunability of microwave responses for current-driven skyrmions in a tapered nanostructure with notches
Authors: P J Krishnanjana , Paikaray Bibekananda , Murapaka Chandrasekhar , Haldar Arabinda
Published: April 2023

The investigation of the gigahertz dynamics of a skyrmion—a topologically protected chiral spin texture, offers several applications in high-frequency magnonic devices. In this work, we have investigated the motion and microwave resonant dynamics of skyrmions in an engineered nanostructure using micromagnetic simulations. The structure is a tapered ferromagnetic/heavy metal bilayer with notches to stabilize the skyrmion for dynamic studies. The skyrmion is moved along the nanostructure via current-induced spin–orbit torques. Multiple stable skyrmion states were demonstrated in the structure, where a remarkable tunability of 6 GHz is observed between the initial and the final state. This large shift in the resonant frequency has been attributed to the variation in the size of the skyrmion at various locations in the engineered nanostructure. The dependency of the skyrmion velocity and their microwave responses on the DzyalosnDzyaloshinskii–Moriya interaction strength and the perpendicular magnetic anisotropy is described. The calculation of the skyrmion Hall angle shed light on the motion and stability of the skyrmion in the structure.
Optimization of uniformity in plasma ashing process using genetic programming
Authors: Moriya Tsuyoshi , Suzuki Yusuke , Yonemichi Hitoshi , Moki Hironori
Published: April 2023

This study is geared toward the optimization of plasma processes through machine learning (ML) based on a regression algorithm. The ML approach has also enabled us to tune the parameters of plasma distribution. As the contribution rate for parameters can be calculated, ML offers the possibility of principal component analysis for a new process window.
A novel hand-eye calibration method using double-layer optimization and outlier sample screening for monocular vision robots
Authors: Chen Lin , Han Ze , Zhong Guowei , Zhang Lei , Chen Yao , Pan Haihong
Published: April 2023

In monocular vision robot systems, the hand-eye calibration approach is crucial for ensuring operational accuracy. A double-layer (Levenberg–Marquardt ([LM] method) optimization (DLMO) method with outlier points screening is proposed to reduce the influence of random errors in robot vision systems and improve the calibration accuracy of the robot hand-eye matrix. First, the equation of the hand-eye matrix is established, and the initial value of the hand-eye matrix is solved by the linear least square method. Second, the Euler angle transformation is applied to the rotation matrix part to ensure its orthogonality. Next, an optimization model of the hand-eye matrix is constructed, and the traditional LM optimization method is used to optimize the initial hand-eye matrix for the first time. Finally, the optimization model of the hand-eye matrix is modified, and the LM optimization method with the outlier sample points screening is applied to optimize the hand-eye matrix for the second time. Hand-eye calibration tests are conducted on an industrial robot equipped with a monocular vision system using the proposed method. Experimental results demonstrate that the average position error of the calibration results obtained by the proposed DLMO method is 0.22 mm, which is superior to the traditional hand-eye calibration method and meets the working requirements of the vision robot in the industrial field.
Unsaturated polyester resin/polymethylmethacrylate waveguide-based refractive index sensor with dual-wavelength temperature compensation
Authors: Yulianti Ian , Marwoto Putut , Astuti Budi , Made D P Ngurah , Fianti  , Paradita Dhea , Darsono Teguh , Ngajikin Nor Hafizah , Yaacob Maslina , Cholan Noran Azizan
Published: April 2023

This paper demonstrates an optical waveguide based- refractive index (RI) sensor using the temperature compensation method. The optical waveguide was formed using a polymethylmethacrylate sheet as the cladding material and unsaturated polyester resin as the core material. The sensor design consists of two input waveguide branches, a sensing area and an output branch. Two light emitting diodes with wavelength of 530 nm and 660 nm were used as light sources. In this work, temperature compensation was done by dual-wavelength technique in which RI and temperature sensitivities were measured at two different wavelengths at 530 nm and 660 nm. Based on the RI and temperature sensitivities, temperature compensation was implemented. Experimental findings indicated that the average relative error of the uncompensated measurement using the light source of 530 nm and 660 nm were 0.4372% and 0.2749%, respectively. Meanwhile, the average error of the temperature compensation method was 0.0344%. Hence, the temperature compensation method provides measurement error up to 92% lower compared to the uncompensated method. As such, the proposed dual-wavelength compensation method could effectively improve the RI measurement accuracy.
Hot atomic vapors for nonlinear and quantum optics
Authors: Glorieux Quentin , Aladjidi Tangui , Lett Paul D , Kaiser Robin
Published: April 2023

Nonlinear optics has been a very dynamic field of research with spectacular phenomena discovered mainly after the invention of lasers. The combination of high intensity fields with resonant systems has further enhanced the nonlinearity with specific additional effects related to the resonances. In this paper we review a limited range of these effects which has been studied in the past decades using close-to-room-temperature atomic vapors as the nonlinear resonant medium. In particular we describe four-wave mixing and generation of nonclassical light in atomic vapors. One-and two-mode squeezing as well as photon correlations are discussed. Furthermore, we present some applications for optical and quantum memories based on hot atomic vapors. Finally, we present results on the recently developed field of quantum fluids of light using hot atomic vapors.
Influence of ZnO/TiO2 nanocomposite on optical and structural properties of OC1C10–PPV–DMP thin film
Authors: Al-Asbahi Bandar Ali , Alanezi Arwa Alhamedi , Asemi Nassar N , Qaid Saif M H , AlSalhi Mohamed S
Published: April 2023

The photophysical properties of poly[2-methoxy-5-(3,7-dimethyl-octyloxy)-1,4-phenylenevinylene]—End capped with dimethylphenyl (DMP), OC1C10–PPV–DMP, were modified by incorporation various contents of the nanocomposites of both anatase TiO2 and wurtzite ZnO (ZTNCs). The solution blending method was employed to prepare the nanocomposite hybrids of OC1C10–PPV–DMP with ZTNCs before depositing them onto glass substrates. The optical parameters of the hybrid nanocomposite thin films were extracted from both absorption and photoluminescence spectra. XRD, FTIR, and FE-SEM revealed the good incorporation of ZTNC into the polymer matrix with the formation of a nanocomposite structure. By increasing the content of ZTNCs in the polymer matrix, the optical parameters of OC1C10–PPV–DMP such as energy band gap, energy tail, steepness parameter, and CIE chromatic coordinates were tuned. The incorporation of ZTNCs resulted in broadened and improved absorption and emission peaks of the polymer with a systematic shift for its corresponding maximum peaks. These unique findings are crucial for improving the performance of optoelectronic devices based on OC1C10–PPV–DMP/ZTNCs.
Structural and magnetic conduct in Sm and Al substituted Ba0.9Sm0.1Fe10Al2O19M-type hexaferrites at different sintering temperatures
Authors: Alshammari Basmah H , Ghori Ubaid-ur-Rehman , Ranjha Qasim Ali , Ahmad Sohail , Abbas Waseem , Asif Sana Ullah , Ahmed Fahim , Ibrahim Fatma A , Hamdy Mohamed S , Eldin Sayed M
Published: April 2023

The hexagonal ferrites with composition Ba0.9Sm0.1Fe10Al2O19has been prepared by using conventional solid state reaction method. As prepared samples were then sintered at different sintering temperatures to analyze the effects on magnetic and structural properties of Barium hexa ferrites. These samples were then characterized by using various techniques. For structural characterization x-ray diffraction technique was used. XRD results confirmed phase pure hexagonal structure. No impurity peaks were observed. For Morphological analysis of all the samples Scanning Electron Microscopy (SEM) was utilized. SEM micrographs suggested the formation of hexaferrites material with homogenous distribution of particles. Magnetic properties were measured by permanent magnetic measuring system. Magnetic conduction of material was tested under varying magnetic field of ± 30 KOe at room temperature. The saturation magnetization value was observed 48.55 emu g−1and coercivity 5.01KOe for the sample sintered at 1220 °C. As the sintering temperature rises, the values for magnetic saturation decreases to 46.24 emu g−1and coercivity increases up to 5.26 KOe at 1270 °C.
Estimating the performance of solar cells with luminescent down-shifting layers
Authors: Bernal-Correa Roberto , Morales-Acevedo Arturo , Montes-Monsalve Jorge
Published: April 2023

Technological developments for improving the performance of conventional solar cells have become a topic of great interest in recent years. For instance, solar concentrators, new anti-reflective coatings, and Luminescent Down-Shifting Layers (LDS), among different techniques have been used in the past. The latter is an attractive option because an LDS layer has the property of increasing the photon flux density in the appropriate wavelength range on top of a cell device with the possibility of increasing the photo-current density. Then, in this work we focus on the development of a theoretical model to determine the cell´s illumination current density, considering the modified solar spectrum, and taking in account the modified spectral reflectance and transmittance at the upper layers when an optimized LDS layer is inserted on a solar cell. The correct selection of such a layer for a specific solar cell would increase its performance due to the enhanced photon density in the absorption region for which the solar cell has the highest quantum efficiency. As an example, it is shown that a Lu3Al5O12:Ce3+ layer on top of a CdTe solar cell might cause an efficiency increase of around 21%.
Robust scheme for high-fidelity generation of mesoscopic entangled cat state
Authors: Zhou Yuan , Li Ying , Wang Jing-Wei , Wang Xing-Chen , Xie Peng , Lü Dong , Li Xin-Ke , Ren Hong-Tao
Published: April 2023

We here study a hybrid quantum system of one solid-state electronic spin coupled to a mechanical resonator (MR) using the crystal strain, with the purpose of engineering the mesoscopic spin-phonon entangled cat state. The feature of this work to be mentioned is that it proposes a different and feasible method to achieve the entanglement, especially with the higher fidelity. This scheme mainly contains two steps, namely the coherent population trapping (CPT) initialization and large-detuning evolution (LDE). By taking all of the adverse decoherence factors into our considerations, the numerical simulations indicate that its fidelity can reach more than 0.995 (or 0.999) when the spin-mechanical coupling strength is 10 (or 100) times larger than spin dephasing and mechanical resonator dissipation rate, respectively. Because of the cooperation of CPT and LDE, this proposal also exhibits a considerable robustness for engineering the entangled cat state, and which may be considered as a general attempt that may be suitable for different systems.
Application of circuit analog optimization method in fast optimization of dynamically tunable terahertz metamaterial sensor
Authors: Zhang Dapeng , Li Zhi , Jia Bowen , Tang Yuan , Yang Zhen
Published: April 2023

The simulation design of terahertz metamaterial sensors with dynamically tunable parameters typically relies on manual parameter tuning for structural optimization. However, this method is often prone to subjective factors and suffer from issues such as frequent reconstruction of simulations, high computational costs, long processing times, and suboptimal optimization results. In this paper, we propose a circuit analog optimization method (CAOM), which constructs equivalent RLC parameters to achieve a highly fitted terahertz transmission spectrum frequency obtained from CST full-wave numerical simulation. To validate the effectiveness of the proposed model, we use a typical periodic structure unit, a double-nested split ring resonator (DSRR) terahertz metamaterial sensor, as the simulation object. Both the inner and outer open resonant rings of the sensor are made of graphene, as a result, the opening size and Fermi level of the resonant rings are dynamically tunable. The results of the validation demonstrate that the adjustments of the sensor parameters can be effectively mapped by the changes of the equivalent RLC parameters. And the proposed equivalent circuit model has parameter substitutability in the simulation modeling of split ring resonator type sensors. The proposed equivalent circuit model exhibits parameter substitution in the simulation modeling of open resonant ring-type sensors. To achieve optimal sensing performance for the electromagnetically induced transparency (EIT)-like resonant peak (with a resonant frequency of f
2) of the sensor under constrained conditions, we introduce the genetic algorithm (GA) into the equivalent circuit model to enable fast optimization of the opening sizes of the inner and outer resonant rings, as well as the Fermi level of the sensor. Moreover, the accuracy of the optimization results is verified by CST simulations. Finally, the optimization results show that the optimal FOM of the EIT-like resonant peak within the given parameter range is 0.712, which is greater than that of any randomly combined parameters. This numerical result demonstrates the effectiveness of the proposed CAOM. The proposed model and optimization method have potentials to inspire further research in device design, performance optimization, theoretical modeling, etc.
An equivalent circuit for magnetoelectric composites operating in a longitudinal mode resonance: BAW-actuated mechanical antenna
Authors: Dong Hongmei , Guo Huihui , Li Junru , Li Jianbo , Gan Xiuxiu
Published: April 2023

It brings new design perspectives to study mechanical antenna in the view of circuit rather than the electromagnetic field. In this paper, an equivalent circuit of bulk acoustic wave (BAW) antenna is constructed by using constitutive relation of magnetoelectric composites and Newton’s governing equation. Based on this circuit, series and parallel resonant frequencies of two phases for BAW antenna are simulated in advanced design system (ADS) and magnetoelectric coupling coefficient is calculated. The results show that the electromechanical coupling coefficient is about 6%, the magnetomechanical coupling coefficient is about 86%, and the magnetoelectric coupling coefficient is about 5.2% under the existing material system (AlN and FeGaB). The magnetoelectric voltage gain is derived based on Kirchhoff’s Current Law, which contributes to studying the influence of the two phases thickness ratio on the performance of BAW antenna. The results show that BAW antenna has the optimal energy coupling and conversion when the thickness ratio of the two phases is 1:1. The input and the output impedances of BAW antenna are calculated by T-parameter matrix, which are perfectly matched with the results in ADS simulation. Relevant experiments have been carried out by preparing the magnetoelectric antenna based on PZT and Terfenol-D materials to verify the universality of the model.
Morphological analysis of the polarized synchrotron emission with WMAP and Planck
Authors: Martire F.A. , Banday A.J. , Martínez-González E. , Barreiro R.B.
Published: April 2023

The bright polarized synchrotron emission, away from the Galactic plane, originates mostly from filamentary structures. We implement a filament finder algorithm which allows the detection of bright elongated structures in polarized intensity maps. We analyse the sky at 23 and 30 GHz as observed respectively by WMAP and Planck. We identify 19 filaments, 13 of which have been previously observed. For each filament, we study the polarization fraction, finding values typically larger than for the areas outside the filaments, excluding the Galactic plane, and a fraction of about 30% is reached in two filaments. We study the polarization spectral indices of the filaments, and find a spectral index consistent with the values found in previous analysis (about -3.1) for more diffuse regions. Decomposing the polarization signals into the E and B families, we find that most of the filaments are detected in PE
, but not in PB
. We then focus on understanding the statistical properties of the diffuse regions of the synchrotron emission at 23 GHz. Using Minkowski functionals and tensors, we analyse the non-Gaussianity and statistical isotropy of the polarized intensity maps. For a sky coverage corresponding to 80% of the fainter emission, and on scales smaller than 6 degrees (ℓ > 30), the deviations from Gaussianity and isotropy are significantly higher than 3σ. The level of deviation decreases for smaller scales, however, it remains significantly high for the lowest analised scale (∼ 1.5°). When 60% sky coverage is analysed, we find that the deviations never exceed 3σ. Finally, we present a simple data-driven model to generate non-Gaussian and anisotropic simulations of the synchrotron polarized emission. The simulations are fitted in order to match the spectral and statistical properties of the faintest 80% sky coverage of the data maps.
Quartz-based Passive Signal Sorter as Radiofrequency Receiver
Authors: Medina I , Martínez D , Suárez D E , Pineda O
Published: April 2023

In this research, we developed a quartz-based passive signal sorter as a radiofrequency receiver, which wirelessly generates voltage from frequency, particularly NFC (13.56MHz), with high efficiency and energy use. Through the electromagnetic field, the passive signal sorter takes advantage of the environment’s frequency to make the quartz oscillate and generate voltage as a result of the piezoelectric effect, along with diodes and capacitors to rectify the electric signal. Among its possible uses, it can be applied to a CUBESAT, since it currently implements solar supply through panels and stores this energy in batteries, because the normal environment limits several types of supply. The CUBESAT spends great periods of time without using direct sunlight, and the farther it is from it, the longer it takes to fill the batteries, and in some particular cases, to reduce the subsystems’ charge. It is suggested that the quartz-based signal sorter works as a reserve source that supplies these batteries by getting energy from the Earth’s electromagnetic fields, preventing as much as possible the lack of energy. The circuit’s development leads to a supply proposal for a CUBESAT system by proving it is economically and volumetrically viable and that it is attractive not only because of the aforementioned benefits but also for being highly efficient and friendly to the environment. It is a great opportunity to implement it in space, industrial, corporate, and household sectors.
Cost Model for CubeSat Projects in Mexico
Authors: Jiménez Navarro E N , Solís Santomé A , Padilla Pérez D A , Domínguez Pacheco F A , Sosa Paz C J , Silva Sánchez C
Published: April 2023

This work focused on designing a cost estimation model in the area of space engineering for the development of nanosatellite projects in Mexico. See employed the use of methodologies such as Hall and Jenkins, software engineering cost estimating methodology, as well as project management methodology. Similarly, the COSYSMO methodology and parametric cost methodology were incorporated to guide this research towards the space sector. The estimation results are based on satellite engineering equations and forecasts of the inflation factor. Finally, a graphical user interface named SACANI was obtained. Allowing the estimating a nanosatellite project by ”integration of components” or by ”research and development”. The first asks the user for the components by subsystem through drop-down lists, giving a breakdown of the estimated costs for the CubeSat, development phases and ground station, according to the data provided by the interested party. The second model is more robust because it requests the type of project, the category, the amount of CubeSat required, the year to estimate the cost, the mass of the payload, among other data. Similarly, both models yield a previous result of the estimate made according to the data entered by the project estimator.
Augmented Reality for Interaction with a CubeSat nanosatellite (ARICS)
Authors: Hernandez Jhonatan Fernando Eulopa , Hernández Emmanuel Cervantes , Perez Diego Alfredo Padilla
Published: April 2023

The development of national aerospace technology has aroused interest in different sectors, so there is a long road to transformation where our country must develop the necessary aerospace infrastructure for said technology. The educational sector has been interested in aerospace technology but the use of this type of technology is expensive. That is why, with the support of ICTs, we think about how to solve this problem and this is where augmented reality (AR) comes in, given that today most young people have a cell phone capable of displaying functions of AR through a mobile application. Currently AR in the aerospace industry is used to support the assembly of complex systems such as aircraft or satellites, and perform simulations of the operation of these systems. That is why this project proposes the use of augmented reality so that anyone has access to interaction with a CubeSat-type nanosatellite from their mobile devices.
OPTIma: a tracking solution for proton computed tomography in high proton flux environments
Authors: Winter A. , Aitkenhead A. , Allinson N. , Allport P. , Cotterill J. , Esposito M. , Green S. , Kirkby K.J. , MacKay R.I. , Manger S. , Merchant M.J. , Price T. , Pyatt S. , Taylor M.J. , Waltham C.
Published: April 2023

Currently there is a large discrepancy between the currents
that are used for treatments in proton beam therapy facilities and
the ultra low beam currents required for many proton CT imaging
systems. Here we provide details of the OPTIma silicon strip based
tracking system, which has been designed for performing proton CT
imaging in conditions closer to the high proton flux environments of
modern spot scanning treatment facilities. Details on the physical
design, sensor testing, modelling, and track reconstruction are
provided along with Monte-Carlo simulation studies of the expected
performance for proton beam currents of up to 50 pA at the nozzle
when using a σ= ∼10 mm spot scanning cyclotron
system. Using a detailed simulation of the proposed OPTIma system, a
discrepancy of less than 1% on the Relative Stopping Power is found
for various tissues when embedded within a 150 mm diameter Perspex
sphere. It is found that by accepting up to 7 protons per bunch it
is possible to operate at cyclotron beam currents up to 5 times
higher than would be possible with a single proton based readout,
significantly reducing the total beam time required to produce an
image, while also reducing the discrepancy between the beam currents
required for treatment and those used for proton CT.