bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of maternal asthma on the preterm infants' gut metabolome and microbiome (MAP study)
Authors: Bai-Tong Shiyu S. , Thoemmes Megan S. , Weldon Kelly C. , Motazavi Diba , Kitsen Jessica , Hansen Shalisa , Furst Annalee , Geng Bob , Song Se Jin , Gilbert Jack A. , Bode Lars , Dorrestein Pieter C. , Knight Rob , Leibel Sydney A. , Leibel Sandra L.
Published: April 2022

Preterm infants are at a greater risk for the development of asthma and atopic disease, which can lead to lifelong negative health consequences. This may be due, in part, to alterations that occur in the gut microbiome and metabolome during their stay in the Neonatal Intensive Care Unit (NICU). To explore the differential roles of family history (i.e., predisposition due to maternal asthma diagnosis) and hospital-related environmental and clinical factors that alter microbial exposures early in life, we considered a unique cohort of preterm infants born ≤ 34 weeks gestational age from two local level III NICUs, as part of the MAP (Microbiome, Atopic disease, and Prematurity) Study. From MAP participants, we chose a sub-cohort of infants whose mothers had a history of asthma and matched gestational age and sex to infants of mothers without a history of asthma diagnosis (control). We performed a prospective, paired metagenomic and metabolomic analysis of stool and milk feed samples collected at birth, 2 weeks, and 6 weeks postnatal age. Although there were clinical factors associated with shifts in the diversity and composition of stool-associated bacterial communities, maternal asthma diagnosis did not play an observable role in shaping the infant gut microbiome during the study period. There were significant differences, however, in the metabolite profile between the maternal asthma and control groups at 6 weeks postnatal age. The most notable changes occurred in the linoleic acid spectral network, which plays a role in inflammatory and immune pathways, suggesting early metabolomic changes in the gut of preterm infants born to mothers with a history of asthma. Our pilot study suggests that a history of maternal asthma alters a preterm infants’ metabolomic pathways in the gut, as early as the first 6 weeks of life.
Measuring the process and rate of exogenous DNA degradation during digestion in mice
Authors: Xing Ruiqi , Liu Hui , Qi Xia , Pan Lingzi
Published: April 2022

This study aimed to perform qualitative and quantitative examination of DNA degradation during the digestion process in the mouse gut through PCR, qPCR and short tandem repeat (STR) analysis. Human blood leukocytes were gavaged into the digestive tract in mice. GAPDH, TH01, TPOX and D7S820 genes in the contents of the stomach and small intestine were analyzed with PCR and qPCR at various times pre- and post-gavage. Through STR analysis, 21 human genomic DNA loci were analyzed. The half-life of DNA degradation, and the relationship between the average peak area and digestion time were determined. The PCR results showed bands of amplified genes at pre-gavage (0 min) and post-gavage (40, 80 and 120 min) from the mouse stomach contents, whereas no DNA bands from small intestinal chyme were observed after gavage. The qPCR results revealed a significant decrease in DNA concentrations during 40–120 min in the mouse stomach after gavage. At 120 min, 85.62 ± 8.10% of the DNA was degraded, and the half-life of exogenous DNA degradation in the mouse stomach was 70.50 ± 5.46 min. At various digestion times, almost no target genes were detected in the mouse small intestinal chyme. STR analysis showed a decrease in allele numbers with bowel advancement in the small intestine in mice. The degradation of exogenous DNA was higher in the mouse stomach during the first 2 h, and almost complete degradation was observed within 40 min after entering the small intestine in mice.
On the pseudo-hyperbolic behavior of charge transfer resistance–temperature dependence in corrosion behavior of Nickel based glass alloy
Authors: Emran Khadijah M. , Omar Inam M. A. , Arab Sanaa T. , Ouerfelli Noureddine
Published: April 2022

Temperature plays an important role in promoting the corrosion of metals. The Arrhenius plot can interpret the corrosion rate-temperature dependence, where the Arrhenius behavior gives a geometrical meaning and makes explicit a positive or negative linear dependence of charge transitivity and temperature. In addition, according to the Arrhenius interpretation, it represents the energy that the molecule in the initial state of the process must acquire before it can take part in the reaction, whether it is a physical, or a chemical process. Taking into account the deviation from the linearity, we have extended the Arrhenius-type expression by one term in 1/T2 and we have given some physical meaning to the new related coefficients for which it is found that they depend closely on the number of acid hydrogen atoms in the polyacid for the corrosion and passivation of the Nickel based metallic glass alloy of the composition Ni82.3Cr7Fe3Si4.5B3.2. Moreover, we can consider that the deviation to the Arrhenius linear behavior as a super-Arrhenius behavior In addition, a mathematical analysis of the trend of experimental scatter points of the charge transfer resistance with temperature permits us to reveal an interesting homographic behavior which leads us to suggest an original empirical model with only two optimal adjustable parameters, as well as a new pseudo-power dependence of the number of hydrogen atoms in the polyacid.
Fabrication of paper-based SERS substrate using a simple vacuum filtration system for pesticides detection
Authors: Ponlamuangdee Kanyawan , Rattanabut Chanoknan , Viriyakitpattana Nopparat , Roeksrungruang Pimporn , Karn-orachai Kullavadee , Pimalai Dechnarong , Bamrungsap Suwussa
Published: April 2022

A paper-based SERS substrate with numerous ‘hotspots’ was fabricated by a simple vacuum filtration method, exhibiting excellent SERS performance for analytes detection.
Multi-interface MoS2/Ni3S4/Mo2S3 composite as an efficient electrocatalyst for hydrogen evolution reaction over a wide pH range
Authors: Sun Rui , Zhao Zhifeng , Su Zhanhua , Li Tiansheng , Zhao Jingxiang , Shang Yongchen
Published: April 2022

The MoS2/Ni3S4/Mo2S3/CC electrode exhibits distinguished electrocatalytic performance toward the HER over a wide pH range.
Tunable emission of Li4SrCaSi2O4−yN2y/3:Eu2+ phosphors based on anion substitution induction for WLEDs and optical thermometry
Authors: Yu Hua , Zhou Liuyan , Ye Renguang , Deng Degang , Xu Shiqing
Published: April 2022

Polychromatic emission can be achieved by controlling the distribution of the rare earth activator in multi-cation lattices, which can be used in the fields of white light LED and fluorescence temperature sensing.
Metal–organic frameworks in pursuit of size: the development of macroscopic single crystals
Authors: Rodrigo Guillermo , Ballesteros-Garrido Rafael
Published: April 2022

The pursuit of macroscopic MOF crystals: an instructive guide.
SERS optical accumulators as unified nanoplatforms for tear sampling and sensing in soft contact lenses
Authors: Mariño-López Andrea , Alvarez-Puebla Ramon A. , Vaz Belén , Correa-Duarte Miguel A. , Pérez-Lorenzo Moisés
Published: April 2022

A novel generation of soft contact lenses synergistically combining molecular size-sieving capabilities and plasmonic properties has been fabricated in order to explore its use as unified sampling and sensing platforms for tear analysis.
Identification of parallel medicinal chemistry protocols to expand branched amine design space
Authors: Conn Edward L. , Perry Matthew A. , Shi Kecheng , Wang Guotao , Hoy Susan , Sach Neal W. , Qi Wenying , Qu Liqiang , Gao Yu , Xu Yan , Schmitt Daniel C.
Published: April 2022

Imine addition strategies for the synthesis of α-branched heteroaryl amine libraries maximize design space for medicinal chemistry.
Enzyme directed evolution using genetically encodable biosensors
Authors: Andon James S. , Lee ByungUk , Wang Tina
Published: April 2022

This review discusses the application of genetically-encodable biosensors toward enzyme directed evolution.
Diversity synthesis of indole derivatives via catalyst control cyclization reaction of 2-indolylmethanols and azonaphthalene
Authors: Cheng Ya-Long , Wu Guoqing , Zang Yong-Jun , Hu Yuan-Yang , Qin Lu-Zhe , Wen Xiaoan , Xu Qing-Long
Published: April 2022

A series of indole fused scaffolds was synthesized via cyclization reaction of 2-indolylmethanol with azonaphthalene. These reactions were realized under mild reaction conditions via catalyst control, providing structurally diverse indole derivative.
Designable assembly of atomically precise Al4O4 cubane supported mesoporous heterometallic architectures
Authors: Liu Ya-Jie , Yu Yinghua , Sun Yi-Fan , Fang Wei-Hui , Zhang Jian
Published: April 2022

Mesoporous heterometallic architectures are designed by the incorporation of the Al4O4 cubane and interpenetration regulation.
The paradigm of drug resistance in cancer: an epigenetic perspective
Authors: Adhikari Swagata , Bhattacharya Apoorva , Adhikary Santanu , Singh Vipin , Gadad Shrikanth S. , Roy Siddhartha , Das Chandrima
Published: April 2022

Innate and acquired resistance towards the conventional therapeutic regimen imposes a significant challenge for the successful management of cancer for decades. In patients with advanced carcinomas, acquisition of drug resistance often leads to tumor recurrence and poor prognosis after the first therapeutic cycle. In this context, cancer stem cells (CSCs) are considered as the prime drivers of therapy resistance in cancer due to their ‘non-targetable’ nature. Drug resistance in cancer is immensely influenced by different properties of CSCs such as epithelial-to-mesenchymal transition (EMT), a profound expression of drug efflux pump genes, detoxification genes, quiescence, and evasion of apoptosis, has been highlighted in this review article. The crucial epigenetic alterations that are intricately associated with regulating different mechanisms of drug resistance, have been discussed thoroughly. Additionally, special attention is drawn towards the epigenetic mechanisms behind the interaction between the cancer cells and their microenvironment which assists in tumor progression and therapy resistance. Finally, we have provided a cumulative overview of the alternative treatment strategies and epigenome-modifying therapies that show the potential of sensitizing the resistant cells towards the conventional treatment strategies. Thus, this review summarizes the epigenetic and molecular background behind therapy resistance, the prime hindrance of present day anti-cancer therapies, and provides an account of the novel complementary epi-drug-based therapeutic strategies to combat drug resistance.
The Effects of Iconic Gestures and Babble Language on Word Intelligibility in Sentence Context
Authors: Wilms Veerle , Drijvers Linda , Brouwer Susanne
Published: April 2022

Purpose:

This study investigated to what extent iconic co-speech gestures help word intelligibility in sentence context in two different linguistic maskers (native vs. foreign). It was hypothesized that sentence recognition improves with the presence of iconic co-speech gestures and with foreign compared to native babble.

Method:

Thirty-two native Dutch participants performed a Dutch word recognition task in context in which they were presented with videos in which an actress uttered short Dutch sentences (e.g.,
Ze begint te openen,
“She starts to open”). Participants were presented with a total of six audiovisual conditions: no background noise (i.e., clear condition) without gesture, no background noise with gesture, French babble without gesture, French babble with gesture, Dutch babble without gesture, and Dutch babble with gesture; and they were asked to type down what was said by the Dutch actress. The accurate identification of the action verbs at the end of the target sentences was measured.

Results:

The results demonstrated that performance on the task was better in the gesture compared to the nongesture conditions (i.e., gesture enhancement effect). In addition, performance was better in French babble than in Dutch babble.

Conclusions:

Listeners benefit from iconic co-speech gestures during communication and from foreign background speech compared to native. These insights into multimodal communication may be valuable to everyone who engages in multimodal communication and especially to a public who often works in public places where competing speech is present in the background.
One‐dimensional high‐gain beam‐scanning transmitarray fed by phased array with continuous electronic scan and low scan loss
Authors: Zhu Liting , Guo Xin , Wu Wen , Fang Da‐Gang
Published: April 2022

In this study, the design of a one‐dimensional high‐gain beam‐scanning transmitarray fed by a phased array with continuous electronic scan and low scan loss is displayed and demonstrated. The feeding linear phased array realizes continuous beam scanning in one plane. And the transmitarray performs phase compensation along another plane to increase the gain. The traditional array‐fed scanning transmitarray has homogeneous phase compensation in one direction. Differently, the phase compensation in the proposed method is carefully designed considering that the beam is scanning. By designing the phase distribution of the transmitarray column by column, the scan loss is successfully reduced. The experimental results of a designed scanning transmitarray fed by a phased array without feeding network show the peak gain of 22.76 dBi and the scan loss of only 1.43 dB within the scanning range of ±35° at the centre frequency of 13.5 GHz. Hence, the advantages of continuous electronic scan, high gain, and low scan loss are validated. Moreover, by integrating the power divider and phase shifters into the feeding phased array, the measured gain increment of 8.26–9.89 dB and the scan loss of 1.74 dB within ±35° are obtained.
Mathematical modelling and control of bearingless brushless direct current machine with motor and generator double modes for flywheel battery
Authors: Liu Yichen , Zhu Huangqiu , Xu Bo
Published: April 2022

The performance of flywheel battery is affected by the vibration and friction of traditional mechanical bearing. A novel kind of bearingless brushless direct current machine (BBLDCM) with the hybrid capabilities of electrical machine and suspension is suitable for flywheel battery which reduces the losses and improves the power quality. The structure and the principle of suspension force in generator are introduced first. Then, the mathematical models of BBLDCM are deduced, especially the mathematical models of suspension force in motor and generator modes. The finite element analysis (FEA) is carried out to prove the validity of the mathematical model and distinguish the difference of mathematical models between the motor mode and the generator mode. Furthermore, the control system of the BBLDCM is established according to the mathematical model deduced above. The simulations of rotation, power generation and suspension are accomplished. Finally, the experiments are carried out through the BBLDCM digital control platform. The results of simulations and experiments show an excellent working performance and a stable suspension of rotor without any mechanical contact of BBLDCM in both motor and generator modes which verify the validity of mathematical models.
The evolution of high-density cores of the BOSS Great Wall superclusters
Authors: Einasto Maret , Tenjes Peeter , Gramann Mirt , Lietzen Heidi , Kipper Rain , Liivamägi Lauri Juhan , Tempel Elmo , Sankhyayan Shishir , Einasto Jaan
Published: April 2022

Context.High-density cores (HDCs) of galaxy superclusters that embed rich clusters and groups of galaxies are the earliest large objects to form in the cosmic web, and the largest objects that may collapse in the present or future.

Aims.We aim to study the dynamical state and possible evolution of the HDCs in the BOSS Great Wall (BGW) superclusters at redshiftz ≈ 0.5 from the CMASS (constant mass) galaxy sample, based on the Baryon Oscillation Spectroscopic Survey (BOSS) in order to understand the growth and evolution of structures in the Universe.

Methods.We analysed the luminosity density distribution in the BGW superclusters to determine the HDCs in them. We derived the density contrast values for the spherical collapse model in a wide range of redshifts and used these values to study the dynamical state and possible evolution of the HDCs of the BGW superclusters. The masses of the HDCs were calculated using stellar masses of galaxies in them. We found the masses and radii of the turnaround and future collapse regions in the HDCs of the BGW superclusters and compared them with those of local superclusters.

Results.We determined eight HDCs in the BGW superclusters. The masses of their turnaround regions are in the range ofMT ≈ 0.4–3.3 × 1015 h−1 M⊙, and radii are in the range ofRT ≈ 3.5–7 h−1Mpc. The radii of their future collapse regions are in the range ofRFC ≈ 4–8 h−1Mpc. Distances between individual cores in superclusters are much larger: of the order of 25–35 h−1Mpc. The richness and sizes of the HDCs are comparable with those of the HDCs of the richest superclusters in the local Universe.

Conclusions.The BGW superclusters will probably evolve to several poorer superclusters with masses similar to those of the local superclusters. This may weaken the tension with the ΛCDM model, which does not predict a large number of very rich and large superclusters in our local cosmic neighbourhood, and explains why there are no superclusters as elongated as those in the BGW in the local Universe.
Exact boundary synchronization for a kind of first order hyperbolic system
Authors: Li Tatsien , Lu Xing
Published: April 2022

In recent years there have been many in-depth researches on the boundary controllability and boundary synchronization for coupled systems of wave equations with various types of boundary conditions. In order to extend the study of synchronization from wave equations to a much larger range of hyperbolic systems, in this paper we will define and establish the exact boundary synchronization for the first order linear hyperbolic system based on previous work on its exact boundary controllability. The determination and estimate of exactly synchronizable states and some related problems are also discussed. This work can be applied to a great deal of diverse systems, and a new perspective to study the synchronization problem for the coupled system of wave equations can be also provided.
5-Year Follow-Up of Endovascular Management in a Patient with Chronic Concomitant DeBakey Type II and IIIa Aortic Dissection
Authors: Siddiq Taofan , Dakota Iwan , Adiarto Suko , Indriani Suci , Sugisman Sugisman , Permana Asmoko Resta , Shu Chang
Published: April 2022

The incidence of chronic concomitant DeBakey Type II and IIIa aortic dissection is uncommon and complex. Since the mortality rate is very high, it requires a precise and holistic treatment plan. In some cases, when the patients refuse to undergo open surgery or the patients' condition is not suitable for open surgery, thoracic endovascular aortic repair (TEVAR) is the recommended therapeutic approach. In this case, a patient refused to undergo open surgery and chose TEVAR instead. The patient survived the procedure and lived for years. We present the case of a successful TEVAR procedure in a patient with chronic concomitant DeBakey Type II and IIIa aortic dissection in a 51-year-old man and the 5-year postoperative follow-up of the patient's condition.
Magnetic Resonance Imaging of Unusual Neoplasms Related to Foramen of Luschka: A Review for Differential Diagnosis
Authors: Demir Mustafa Kemal , Özdamarlar Umut , Yılmaz Baran , Akakın Akın , Kılıc Turker
Published: April 2022

There are many types of neoplasms in or around the foramen of Luschka (FL), and definitive diagnosis in some cases requires knowledge of imaging findings. The uncommon and challenging neoplasms with FL involvement considered in this study are exophytic brainstem glioma, primary glioblastoma of the cerebellopontine angle (CPA), primary anaplastic ependymoma of the CPA, choroid plexus papilloma of the FL, solitary FL choroid plexus metastasis, extraskeletal myxoid chondrosarcoma of the jugular foramen, paraganglioma of the jugular foramen, exostosis of the jugular foramen, psammomatous meningioma in the lateral cerebellar medullary cistern, epidermoid tumor of the fourth ventricle, and a hypoglossal schwannoma. These neoplasms may have overlapping clinical and imaging features, but some have relatively distinct imaging features. Knowledge of the key clinical and magnetic resonance imaging features of these unusual lesions with FL involvement is important for radiologists to improve diagnostic ability and to assist the referring physician in the appropriate management of the patient.
Quality of Life among Survivors of Locally Advanced Cervical Cancer Treated with Definitive Chemoradiotherapy in a Decade of Transition
Authors: Chua Vannesza Hendricke , Yu Kelvin Ken , Chua Patricia Andrea , Chua Raphael Joseph , Chua Robeley May , Chun Yae Na , Mariano Jocelyn , Gonzalez Gil , Ortin Teresa Sy , Bacorro Warren
Published: April 2022

Introduction The standard treatment for locally advanced cervical cancer (LACC) is concurrent chemoradiotherapy (CRT). External beam radiotherapy (EBRT) and brachytherapy (BRT) advances in the last decade have resulted in improved local control and survival. There is a lack of data on quality of life (QoL) among survivors.

Objective This systematic review aimed to synthesize published data on QoL among LACC survivors treated with CRT and determine clinical factors of QoL.

Methods Systematic literature search was conducted in PubMed, EBSCO, and ScienceDirect for relevant articles published in 2010 to 2020. Eligible studies on LACC survivors aged 18 years and above, who reported QoL after CRT, were included. Screening and data extraction were done by two pairs of independent reviewers.

Results Five cohort studies, three cross sectional studies, and one clinical trial were included. Reported temporal evolution of QoL varied: two studies reported improvement of overall QoL, while four reported worsening of symptoms. Gastrointestinal, genitourinary, sexual, and psychosocial domains showed significant impairment. Age, stage, and baseline distress and physical condition were clinical determinants of body image, sexual activity, menopausal symptoms, distress, and dyspnea. Peripheral neuropathy, lymphedema, and dyspnea were reported, while grade 3 to 4 gastrointestinal, genitourinary, and musculoskeletal toxicities were rare.

Conclusion Use of advanced EBRT and BRT techniques is associated with improving QoL in the first 3 years from treatment completion. Gastrointestinal, genitourinary, sexual, and psychosocial functions remain impaired on the long-term. Other late toxicities worth noting include peripheral neuropathy, lower limb edema, and insufficiency fractures.
An instrument for in situ characterization of powder spreading dynamics in powder-bed-based additive manufacturing processes
Authors: Escano Luis I. , Parab Niranjan D. , Guo Qilin , Qu Minglei , Fezzaa Kamel , Everhart Wes , Sun Tao , Chen Lianyi
Published: April 2022

In powder-bed-based metal additive manufacturing (AM), the visualization and analysis of the powder spreading process are critical for understanding the powder spreading dynamics and mechanisms. Unfortunately, the high spreading speeds, the small size of the powder, and the opacity of the materials present a great challenge for directly observing the powder spreading behavior. Here, we report a compact and flexible powder spreading system for in situ characterization of the dynamics of the powders during the spreading process by high-speed x-ray imaging. The system enables the tracing of individual powder movement within the narrow gap between the recoater and the substrate at variable spreading speeds from 17 to 322 mm/s. The instrument and method reported here provide a powerful tool for studying powder spreading physics in AM processes and for investigating the physics of granular material flow behavior in a confined environment.
Development of a diagonal-cut type beam position monitor for the booster ring in the High Intensity Heavy-Ion Accelerator Facility project
Authors: Du Ze , He Peilin , Zhu Guangyu , Caspers Fritz , Li Zhixue , Wu Junxia , Hu Xuejing , Zhang Zhaolong , Xie Hongming , Ni Fafu , Zhang Yong , Yang Yongliang , Yang Jiancheng , Meng Jun
Published: April 2022

A diagonal-cut type beam position monitor (BPM) has been developed for the High Intensity Heavy-Ion Accelerator Facility (HIAF) project at the Institute of Modern Physics. Compared with other types of BPMs, the diagonal-cut type BPM has almost perfect position linearity, i.e., no non-linear correction required, which is advantageous for beams that are transversally large and have a complex charge distribution. The key parameters for the diagonal-cut type BPM have been simulated and optimized in detail and systematically herein. It was found that the crosstalk is improved by ∼10 dB at 160 MHz by insertion of a separate ring between two horizontal or vertical electrodes of the BPM made of stainless steel with vacuum as a dielectric. Furthermore, the longitudinal and transverse numerical simulation to evaluate the beam impedance on the diagonal-cut type BPM has been performed. The results for the crosstalk, position sensitivity, and electrode capacitance to ground obtained from simulations and laboratory measurements agree well. The vacuum of the BPM prototype after baking out at 250 °C for 72 h is better than 1.0 × 10−11 mbar. The simulated and on-line measured BPM output signal magnitude results are consistent with each other. This diagonal-cut type BPM structure will be considered for application to the HIAF project as a priority.
A numerical investigation of methane ignition in supercritical CO2
Authors: Ovais Syed Mohammad , Miller Richard S.
Published: April 2022

The supercritical CO2 power cycle (sCO2) is a relatively new technology, which promises to reduce CO2 emissions with potentially higher efficiencies. However, due to challenging conditions posed by supercritical pressures, the ignition phenomena in sCO2 combustion are relatively less understood and studied. The primary objective of the current study is to elucidate ignition processes using homogeneous ignition calculations (HMI) and two-dimensional direct numerical simulations (DNS). To accurately model the supercritical conditions, the employed formulation includes the cubic Peng–Robinson equation of state, mass, and heat flux vectors derived from nonequilibrium thermodynamics and compressible form of governing equations. For selection of a suitable chemical mechanism, HMI calculations are employed to investigate the performance of existing skeletal mechanisms against shock-tube experimental data. The chemical characteristics of ignition are further studied using path flux and sensitivity analysis, with CH3O2 chemistry exhibiting the largest effect on accelerating the ignition process. Different chemical pathways of fuel breakdown are also discussed to aid in interpretation of subsequent DNS case. In the DNS case, autoignition of a two-dimensional mixing layer perturbed with pseudoturbulence is simulated. The ignition is found to be delayed compared to the HMI case, with the ignition kernels forming in a spotty manner. The two phenomena are primarily attributed to variation of scalar dissipation within the mixing layer. The ignition kernels expand and evolve into a tribrachial edge flame propagating along the stoichiometric isosurface. Further investigation on the structure of edge flame revealed an asymmetrical structure, with CH4 molecules being entirely consumed in the triple point region of the flame along the stoichiometric isosurface, and more stable fuels like CO burning in the non-premixed branch of the edge flame. The edge flame propagation speeds are also calculated, with variations found to be correlated with scalar dissipation and upstream progress variable of the reacting mixture.
Distributed surface compliance for airfoil tonal noise reduction at various loading conditions
Authors: Arif Irsalan , Lam Garret C. Y. , Leung Randolph C. K. , Naseer Muhammad Rehan
Published: April 2022

A novel concept of utilizing distributed surface compliance to achieve airfoil tonal noise reduction at various loading conditions is proposed. The aeroacoustics of airfoil configuration subjected to different loading conditions at angles of attack (AoAs) from 3° to 7° are numerically studied using high-fidelity two-dimensional direct aeroacoustic simulation at Reynolds and Mach numbers of 5×104 and 0.4, respectively. Initially, airfoil configurations mounted with single elastic panel (SEP) at individual AoA are designed with the knowledge of respective rigid airfoil flow characteristics. Stemming from the analysis of noise reduction potential of SEP configurations using a reduced-order modeling approach, a distributed surface compliance (DSC) airfoil configuration utilizing three resonating panels is designed to attain airfoil tonal noise reduction over entire range of AoA. Comprehensive acoustic analyses establish that the DSC airfoil could provide a maximum noise reduction ranging from 3 to 7 dB without any sacrifice in airfoil aerodynamics. The extent of noise reduction with DSC airfoil is found dependent on the flow-induced modal responses of the panels. At lower AoA, the panel(s) resonate in their designed structural modes, which remarkably weaken the flow instabilities convecting over the airfoil suction surface and eventually airfoil noise radiation. At higher AoA, the panel responses deviate from their designed structural mode shapes but could still give less noise reduction. Therefore, the designed DSC airfoil shows a feasible concept for tonal noise reduction over a wide range of operational AoA, which substantiates its applicability for aerodynamic devices at low Reynolds numbers.
Comparative study of transonic shock–boundary layer interactions due to surface heating and cooling on an airfoil
Authors: Sengupta Tapan K. , Chakraborty Ardhendu , Roy Arkadyuti Ghosh , Sengupta Aditi , Sundaram Prasannabalaji
Published: April 2022

Implicit large eddy simulation results are compared to investigate the effects of wall-heating and wall-cooling on shock–boundary layer interaction over an airfoil. Heat flux is provided on the suction surface of the airfoil from x/c=0.40 to x/c=0.50 for a Mach number of 0.72 and a Reynolds number based on chord of Re=16.2×106. Flow quantities are compared for the effects of heating and cooling. Numerical Schlieren snapshots reveal an oscillation of the shock wave and its interaction with upstream propagating Kutta waves generated from the trailing edge of the airfoil. Quantitative data obtained from these Schlieren snapshots and the mean aerodynamic load values indicate a reduction in frequency of oscillation of shock wave and a decrease in shock strength for the case of heating. Flow control by heating shows higher fluctuations in flow features evident from instantaneous quantities. Both imposed excitations lead to a marginal increase in aerodynamic efficiency (lift/drag). We also compare the integral aerodynamic parameters, such as lift and drag coefficients, and their ratio, Cl, Cd,and  Cl/Cd. The simulations reported here follow the techniques used in Sengupta et al. [“Thermal control of transonic shock–boundary layer interaction over a natural laminar flow airfoil,” Phys. Fluids 33(12), 126110 (2021)].
Utility computable modeling of a Boltzmann model equation for bimolecular chemical reactions and numerical application
Authors: Wu Jun-Lin , Li Zhi-Hui , Peng Ao-Ping , Pi Xing-Cai , Jiang Xin-Yu
Published: April 2022

A Boltzmann model equation (kinetic model) involving the chemical reaction of a multicomponent gaseous mixture is derived based on Groppi's work [“A Bhatnagar–Gross–Krook-type approach for chemically reacting gas mixtures,” Phys. Fluids 16, 4273 (2004)], in which the relaxation parameters of elastic collision frequency for rigid elastic spheres are obtained based on the collision term, and the pivotal collision frequency of the chemical reaction is deduced from the chemical reaction rate that is determined by the direct simulation Monte Carlo (DSMC) method. This kinetic model is shown to be conservative, and the H theorem for an endothermic reaction is proven. In the framework of the gas-kinetic unified algorithm, the discrete velocity method, finite volume method, and implicit scheme are applied to solve the proposed kinetic model by introducing a suitable boundary condition at the wall surface. For hypersonic flows around a cylinder, the proposed kinetic model and the corresponding numerical methods are verified for both endothermic and exothermic reactions by comparison of the model's results with results from the DSMC method. The different influences of endothermic and exothermic reactions are also given. Finally, the proposed kinetic model is also used to simulate an exothermic reaction-driven flow in a square cavity.
Intelligent ship anti-rolling control system based on a deep deterministic policy gradient algorithm and the Magnus effect
Authors: Lin Jianfeng , Han Yang , Guo Chunyu , Su Yumin , Zhong Ruofan
Published: April 2022

Anti-rolling devices are widely used in modern shipboard components. In particular, ship anti-rolling control systems are developed to achieve a wide range of ship speeds and efficient anti-rolling capabilities. However, factors that are challenging to solve accurately, such as strong nonlinearities, a complex working environment, and hydrodynamic system parameters, limit the investigation of the rolling motion of ships at sea. Moreover, current anti-rolling control systems still face several challenges, such as poor nonlinear adaptability and manual parameter adjustment. In this regard, this study developed a dynamic model for a ship anti-rolling system. In addition, based on deep reinforcement learning (DRL), an efficient anti-rolling controller was developed using a deep deterministic policy gradient (DDPG) algorithm. Finally, the developed system was applied to a ship anti-rolling device based on the Magnus effect. The advantages of reinforcement learning adaptive control enable controlling an anti-rolling system under various wave angles, ship speeds, and wavelengths. The results revealed that the anti-rolling efficiency of the intelligent ship anti-rolling control method using the DDPG algorithm surpassed 95% and had fast convergence. This study lays the foundation for developing a DRL anti-rolling controller for full-scale ships.
Food web rewiring drives long-term compositional differences and late-disturbance interactions at the community level
Authors: Polazzo Francesco , Marina Tomás I. , Crettaz-Minaglia Melina , Rico Andreu
Published: April 2022

Significance

Multiple anthropogenic disturbances affect the structure and functioning of communities. Recent evidence highlighted that, after pulse disturbance, the functioning a community performs may be recovered fast due to functional redundancy, whereas community multivariate composition needs a longer time. Yet, the mechanisms that drive the different community recovery times have not been quantified empirically. We use quantitative food-web analysis to assess the influence of species interactions on community recovery. We found species-interactions strength to be the main mechanism driving differences between structural and functional recovery. Additionally, we show that interactions between multiple disturbances appear in the long term only when both species-interaction strength and food-web architecture change significantly.
Origin of iodine preferential attack at sulfur in phosphorothioate and subsequent P-O or P-S bond dissociation
Authors: Huang Qiang , Lee Ga Young , Li Jiayi , Wang Chuan , Zhao Rosalinda L. , Deng Zixin , Houk K. N. , Zhao Yi-Lei
Published: April 2022

Significance

Iodine-induced cleavage is widely used for detecting bacterial DNA phosphorothioation in gel electrophoresis, deep sequencing, and single-molecule optical mapping. However, we lack quantitative understanding of the phosphorothioate DNA (PT-DNA) cleavage efficiency and the chemoselectivity of this method for determination of phosphorothioate vs. phosphate. Computational explorations now reveal why iodine selectively attacks at sulfur in phosphorothioate links but not at normal phosphates. The active role of Tris buffer in the PT-DNA cleavage, and the factors controlling cleavage efficiency, were also revealed. Cleavage efficiency is limited by competition between the desired DNA backbone cleavage and unwanted P-S/P-O conversion. These mechanistic studies will guide the development of new methods for iodine-induced specific PT-DNA cleavage.
Cross-talk between mutant p53 and p62/SQSTM1 augments cancer cell migration by promoting the degradation of cell adhesion proteins
Authors: Mukherjee Saptaparna , Maddalena Martino , Lü YiQing , Martinez Sebastien , Nataraj Nishanth Belugali , Noronha Ashish , Sinha Sansrity , Teng Katie , Cohen-Kaplan Victoria , Ziv Tamar , Arandkar Sharathchandra , Hassin Ori , Chatterjee Rishita , Pirona Anna-Chiara , Shreberk-Shaked Michal , Gershoni Anat , Aylon Yael , Elazar Zvulun , Yarden Yosef , Schramek Daniel , Oren Moshe
Published: April 2022

Significance

Missense mutations in the
TP53
gene, encoding the p53 tumor suppressor, are very frequent in human cancer. Some of those mutations, particularly the more common (“hotspot”) ones, not only abrogate p53’s tumor suppressor activities but also endow the mutant protein with oncogenic gain of function (GOF). We report that p53
R273H
, the most common p53 mutant in pancreatic cancer, interacts with the SQSTM1/p62 protein to accelerate the degradation of cell adhesion proteins. This enables pancreatic cancer cells to detach from the epithelial sheet and engage in individualized cell migration, probably augmenting metastatic spread. By providing insights into mechanisms that underpin mutant p53 GOF, this study may suggest ways to interfere with the progression of cancers bearing particular p53 mutants.
Self-adaptive integration of photothermal and radiative cooling for continuous energy harvesting from the sun and outer space
Authors: Ao Xianze , Li Bowen , Zhao Bin , Hu Mingke , Ren Hui , Yang Honglun , Liu Jie , Cao Jingyu , Feng Junsheng , Yang Yuanjun , Qi Zeming , Li Liangbin , Zou Chongwen , Pei Gang
Published: April 2022

Significance

The sun (∼6,000 K) and outer space (∼3 K) are two natural energy resources for humans. However, most of the approaches of energy harvesting from the sun and rejecting energy to outer space are achieved independently using absorbers and emitters with static spectral properties. Herein, a spectrally self-adaptive structure with strong solar absorption and switchable emissivity within the atmospheric window (i.e., 8 to 13 μm) is experimentally demonstrated to achieve diurnal solar thermal and nocturnal radiative cooling efficiently. The experiment shows that the proposed structure not only can be heated to 185°C in diurnal mode but also be cooled to −12°C in nocturnal mode. This work opens new possibilities for continuously efficient energy harvesting utilizing the sun and the universe.
Improvement of inhomogeneity of microstructure and mechanical properties for 316 stainless steel laser-MIG hybrid welded joint assisted by alternating magnetic field
Authors: Liu Fuyun , Tan Caiwang , Ma Guolong , Han Xiaohui , Chen Bo , Song Xiaoguo , Zhao Hongyun , Wang Guodong
Published: April 2022

An alternating magnetic field was employed to improve inhomogeneity of microstructure and mechanical properties of laser-MIG hybrid welded 316 stainless steel joints. More uniform distribution of elements and ferrite phase, and austenite crystallographic characteristics in upper arc zone and lower laser zone of weld were obtained by alternating magnetic field, due to mixing of molten metal in whole weld. Longer solidification time of molten pool and more nucleation sites of austenite grain were obtained by stirring effect of magnetic field, leading to reduction of ferrite content and refinement of austenite grain. The hardness in vertical weld was more homogeneous and difference of tensile strength in both zones was reduced from 74 MPa to 10 MPa by magnetic field, due to microstructural homogeneity.
Butt welding of TiZrMoCuBe MGC/TC4 titanium alloy using a pulsed Nd:YAG laser
Authors: Li Ke , Chen Minghua , Liu Liang , Wu Fufa
Published: April 2022

β-Ti dendrite toughened metal glass composite and TC4 titanium alloy were butt welded by a pulsed laser. Microstructures and mechanical properties of the welded joint were specially studied. Results show that microstructure in the fusion zone is uneven, and mainly consists of dendritical β-Ti grains (in nanometre or micron scales) and amorphous alloy background. Special chemical compositions of base materials, shocking effect from laser pulses and large cooling speed during welding directly restrain the development of crystal β-Ti grain in the fusion zone. Hardness in the fusion zone ranges from 500 HV to more than 600 HV. During tensile tests, all the welded joints fracture on TC4 titanium alloy base material side.
No diurnal variation is present in maximal fat oxidation during exercise in young healthy women: A cross‐over study
Authors: Robles‐González Lidia , Aguilar‐Navarro Millán , López‐Samanes Álvaro , Ruiz‐Moreno Carlos , Muñoz Alejandro , Varillas‐Delgado David , Gutiérrez‐Hellín Jorge , Helge Jørn W. , Ruiz Jonatan R. , Amaro‐Gahete Francisco J.
Published: April 2022

Maximal fat oxidation during exercise (MFO) and the intensity that elicits MFO (Fatmax) seems to show a diurnal variation in men, which favours an increased performance in the afternoon than the morning. At present, it remains unknown whether the observed MFO and Fatmax diurnal variation in men is also present in women. Therefore, the current study examined the diurnal variations of MFO and Fatmax in women. Nineteen healthy women (age: 26.9 ± 8.7 years, maximum oxygen uptake: 39.8 ± 6.5 ml/kg/min) participated in the study. MFO and Fatmax were determined by a graded exercise test in cycloergometer using a cross‐over design performed on two separate daytime schedules, one conducted in the morning (8am–11am) and one in the afternoon (5pm–8pm). Stoichiometric equations were used to calculate fat oxidation rates. There were no significant differences between MFO‐morning and MFO‐afternoon (0.24 ± 0.10 vs. 0.23 ± 0.07 g/min, respectively; P = 0.681). Similarly, there was no significant differences between Fatmax‐morning and Fatmax‐afternoon (41.1 ± 4.7 vs. 42.6 ± 5.5% of maximal oxygen uptake, respectively; P = 0.305). These results persisted after controlling for fat mass percentage (all P > 0.5). In summary, the main finding of the present study was that MFO and Fatmax were similar independent of the time‐of‐day when the exercise test is performed in healthy women. These results have important clinical implications since they suggest that, in contrast to what was found in men, MFO and Fatmax show similar rates during the course of the day in women.

Highlights

MFO and Fatmax were similar during the afternoon and morning in young healthy women.

Our results suggest that, in women, it does not matter when endurance exercise is performed in term of fat metabolism during exercise.
Dynamic and fluctuation properties of a graphene disk levitated by a diamagnetic force in air
Authors: Inui Norio , Maebuchi Kazunori
Published: April 2022

A graphene disk can be levitated above a magnet by a repulsive force arising from their diamagnetic interaction if the product of the magnetic field and its gradient is sufficiently large. The diamagnetic force also causes the rotation of the graphene disk because of the strong anisotropy of the magnetic permeability of graphene; thus a motion of centroid and rotation are considered by solving simultaneous Langevin equations. Furthermore, the dependence of a fluctuations of the position and angle of the levitated graphene disk on the size and temperature is also explained.
Deep blue exciplex tandem OLEDs using n- and p-doped planar heterojunction as a charge generation layer
Authors: Fan Yuxuan , Sun Ahui , Tian Yuhe , Zhou Pengchao , Niu Yixiao , Shi Wei , Wei Bin
Published: April 2022

The tandem organic light-emitting diodes (OLEDs) have the advantages of small current density, high current efficiency (CE), and long lifetime. We have developed the conventional and inverted tandem OLEDs using n- and p-doped planar heterojunction as a charge generation layer (CGL). The CGL consists of the bathophenanthroline:Cs2CO3 and N,N’-di-[(1-naphthalenyl)-N,N’-diphenyl]-1,1′-biphenyl)-4,4′-diamine:MoO3 bilayer structure to connect the deep blue- and deep red-emitting units. The turn-on voltage, luminescence, CE, and external quantum efficiencies of the conventional tandem OLED are 7.2 V, 5083 cd m−2, 8.45 cd A−1, and 13.94%, respectively, and the color rendering ability remains stable at a high current density of 60 mA cm−2. Moreover, the efficiency roll-off of the inverted tandem OLED is optimized to 5.5% at a luminance of 1000 cd m−2. Furthermore, a large-area (50 × 50 mm2) parallel OLEDs with a tunable red-emitting area are fabricated. The development of the OLEDs provides a new direction for the application of OLEDs in plant growth.
Antiferromagnetic short-range order and cluster spin-glass state in diluted spinel ZnTiCoO4
Authors: Chowdhury Mouli Roy , Seehra Mohindar S , Pramanik Prativa , Ghosh Sayandeep , Sarkar Tapati , Weise Bruno , Thota Subhash
Published: April 2022

The nature of magnetism in the doubly-diluted spinel ZnTiCoO4 = (Zn2+)
A
[Ti4+Co2+]
B
O4 is reported here employing the temperature and magnetic field (H) dependence of dc susceptibility (χ), ac susceptibilities (χ′ and χ″), and heat capacity (C
p) measurements. Whereas antiferromagnetic (AFM) Néel temperature T
N = 13.9 K is determined from the peak in the ∂(χT)/∂T vs T plot, the fit of the relaxation time τ (determined from the peak in the χ″ vs T data at different frequencies) to the Power law: τ = τ
0 [(T − T
SG)/T
SG]−zν
yields the spin glass freezing temperature T
SG = 12.9 K, z
ν ∼ 11.75, and τ
0 ∼ 10−12 s. Since the magnitudes of τ
0 and z
ν depend on the magnitude of T
SG, a procedure is developed to find the optimum value of T
SG = 12.9 K. A similar procedure is used to determine the optimum T
0 = 10.9 K in the Vogel–Fulcher law: τ = τ
0 exp[E
a/k
B(T − T
0)] yielding E
a/k
B = 95 K, and τ
0 = 1.6 ×  10−13 s. It is argued that the comparatively large magnitude of the Mydosh parameter Ω = 0.026 and k
B
T
0/E
a = 0.115 (≪1) suggests cluster spin-glass state in ZnTiCoO4 below TSG. In the C
p vs T data from 1.9 K to 50 K, only a broad peak near 20 K is observed. This and absence of λ-type anomaly near T
N or T
SG combined with the reduced value of change in magnetic entropy from 50 K to 1.9 K suggests only short-range AFM ordering in the system, consistent with spin-glass state. The field dependence of T
SG shows slight departure (ϕ ∼ 4.0) from the non-mean-field Almeida–Thouless line T
SG(H) = T
SG(0) (1 − AH
2/ϕ
). Strong temperature dependence of magnetic viscosity S and coercivity H
C without exchange bias, both tending to zero on approach to T
SG from below, further support the spin-glass state which results from magnetic dilution driven by diamagnetic Zn2+ and Ti4+ ions leading to magnetic frustration. Magnetic phase diagram in the H–T plane is established using the high-field magnetization data M(H, T) for T < T
N which reveals rapid decrease of T
SG with increase in H whereas decrease in T
N with increase in H is weaker, typical of AFM systems. For T > T
N, the data of χ vs T are fit to the modified Curie–Weiss law, χ = χ
0 + C/(T + θ), with χ
0 = 3.2 × 10−4 emu mol−1 Oe−1 yielding θ = 4 K and C = 2.70 emu K mol−1 Oe−1. This magnitude of C yields effective magnetic moment = 4.65 μ
B for Co2+, characteristic of Co2+ ions with some contribution from spin–orbit coupling. Molecular field theory with effective spin S = 3/2 of Co2+ is used to determine the nearest-neighbor exchange constant J
1/k
B = 2.39 K AFM and next-nearest-neighbor exchange constant J
2/k
B = −0.66 K (ferromagnetic).