bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of chaotic system based on least squares support vector machine modeling
Authors: Ye Mei-Ying  ,   浙江师范大学数理学院,金华  321004
Published: December 2020

A new approach to control chaotic systems is presented. This control approach is based on least squares support vector machines (LS_SVMs) modeling. Compared wit h the feed_forward neural networks, the LS_SVM possesses prominent advantages: o ver fitting is unlikely to occur by employing structural risk minimization crite rion, the global optimal solution can be uniquely obtained owing to the fact tha t its training is performed through the solution of a set of linear equations. A lso, the LS_SVM need not determine its topology in advance, which can be automat ically obtained when the training process ends. Thus the effectiveness and feasi bility of this method are found to be better than those of the feed_forward neur al networks. The method does not needs an analytic model, and it is still effect ive when there are measurement noises. The chaotic systems with one_and two_ dim ensional nonlinear maps are used as examples for demonstration.
Study on the effect of external electric field excitation on methane
Authors: Xu Guo-Liang  , Zhu Zheng-He  , Ma Mei-Zhong  , Xie An-Dong  ,   四川大学原子与分子物理研究所,成都  610065
Published: December 2020

The present paper is devoted to the calculation of transition wavelengths, os cillator strengths f, Einstein An0 and B0n coefficients of methane from ground state Ｘ～lＡl to the first six di fferent excited states by employing density functional theory and single substitute con figuration interaction (CIS) approach with basis sets 6-311++G**. At the same time, the excited states of methane under an external electric field are i nvestigated. It is shown that the total energy of the system has little change d, and simultaneously the HOMO-LUMO gaps become small and the Fermi levels dec lines slightly as the external electric field intensity become strong. The trans ition between ground state Ｘ～lＡl and the high-excited state of methane is easy bring about.
THz spectrum of aromatic amino acid
Authors: Yue Wei-Wei  , Wang Wei-Ning  , Zhao Guo-Zhong  , Zhang Cun-Lin  , Yan Hai-Tao  ,   首都师范大学物理系,北京  100037
Published: December 2020

We have studied the optical properties of three kinds of aromatic amino acids including tyrosine, tryptophane and phenylalanine using THz time domain spectroscopy between 0.2 and 1.6 THz.Comparing their absorption spectra,we find that tyros ine and tryptophane have sharp absorption peaks at 0.976THz and 1.465THz respect ively,while phenylalanine does not have absorption peak in this range.This resul t shows the capability of THz time domain spectroscopy to distinguish different molecules.Calculating by density functional,we found that the absorption peaks a re caused by the rotation and torsion of the molecules.The average refractive in dexes of these three amino acids are also obtained:they are 1.507,1.526 and 1.68 6 respectively.This work not only is significant for the research of molecular s tructure and molecular dynamics,but can also provide reference for studying othe r large biological molecules by THz time domain spectroscopy.
Characterisation of the crystal structure of La0.4FeCo3Sb12 by means of x-ray and electron diffractions
Authors: Xu Min  , Sheng Wen  , Gao Zhan  , Zhao Liang-Lei  , Jiang Bei  , Yang Lei  , Zhang Lan-Ting  ,   上海交通大学材料科学与工程学院，教育部高温材料及测试开放实验室，上海  200030
Published: December 2020

The crystal structure and its evolution of an n-type La20.4FeCo3 Sb12 compound have been characterized by the Rietveld refinemen t and TEM observation. An interstitial site 01980nm in radius has been found in the lattice of t he binary Skutterudite compound. Filling this interstitial site by rare earth at om mainly results in a change of lattice coordinates of the Sb atom in the compo und. Thermal vibration parameter of the rare earth atom is larger than those of other atoms. The electron diffraction patterns confirm the bcc structure of this compound. The intensities of diffraction from different crystallographic planes correspond well between electron and powder x-ray diffractions.
Symmetrical invariant transformation of localization length in one-dimensional randomly-perturbed periodic structure
Authors: Han Peng  , Wang He-Zhou  ,   (1)中山大学光电材料与技术国家重点实验室,广州  510275; (2)中山大学光电材料与技术国家重点实验室,广州  510275;华南师范大学物理系,广州  510631
Published: December 2020

Based on the spectral symmetry of the one-dimensional periodic structure, a new invariant transformation, named symmetrical invariant transformation, of localization length is presented for the one-dimensional randomly-perturbed periodic structure. The validity of the transformation is confirmed by numerical stimulations performed by means of transfer-matrix method. Since the symmetrical invariant transformation explores an equivalent relation of localization length at different frequencies between different structures, it is expected to provide a new tool for further investigation of the light localization in disordered structures.
Effect of annealing and polarizing temperature on the trap level distribution in nylon 11 film electrets
Authors: Zhu Jun  , Zhang Xing-Yuan  , Lu Hong-Bo  ,   中国科学技术大学高分子科学与工程系，合肥  230026
Published: December 2020

The effect of annealing and polarizing temperature on the trap level distribution in nylon 11 film electrets has been studied by thermally stimulated depolariza tion current (TSDC) technique. It was found that there were four detrapping curr ent peaks of space charge in TSDC spectra of the quenched nylon 11 film electret , while two in that of the annealed one. Using multi-point method to fit the ex perimental curves, the detrapping current peaks could be separated and the trap depth was obtained. The results further proved that there were four trap levels of space charge in a quenched electret and the trap level distribution changed l ittle when the polarization temperature increased; while after annealing, there were only two trap levels in the electret. The results also showed that the shal lower trap level was obviously close to the deeper trap level when the polarizat ion temperature increased.
Numerical simulation and characteristic comparison of Spindt type and diamond film field emisson
Authors: Liu Jun-Qiao  , Zhan Jie-Min  ,   中山大学应用力学与工程系，广州  510275
Published: December 2020

By using the electromagnetic particle-in-cell(PIC) MAGIC code, the process of field emission is simulated. The simulation includes two representative field emission devices(Spindt-type field emitter and diamond film field emitter). For Spindt-type field emitter, the relation between the characteristics and the radius of curvature of the emitter tip , the relative height between the emitter tip and the gate are studied. As regards the diamond film field emitter, the characteristics of field emission microtriodes and microtetrodes are compared with each other and the influence of the area of diamond film is investigated. The resul ts show that the characteristics of diamond film field emitter has an advantage over Spindt-type field emitter.
X-ray diffraction investigation of single-crystal Co nanowires
Authors: Meng Fan-Bin  , Hu Hai-Ning  , Li Yang-Xian  , Chen Gui-Feng  , Chen Jing-Lan  , Wu Guang-Heng  ,   (1)河北工业大学材料学院，天津  300130; (2)中国科学院物理研究所北京凝聚态物理国家实验室，北京  100080
Published: December 2020

Structure and morphology of single-crystalline hcp Co nanowires fabricated by electrodeposition were investigated in detail by various x_ray diffraction method s. The results confirm that the Co nanowires can be deposited in single crystall ine with the same crystal orientation of ［100］ along the longitudinal axes. The arrays were composed from those nanowires preferentially in ［100］ direction with very high parallelity, but the ［001］ axis of the nanowires randomly lies in the array plane. By slightly higher depositing voltage, some twisted deformat ion could happen in the nanowires with chiral behavior. A twisted model has been brought forward to explain the experimental results. Magnetization properties m easured by superconducting quantum interference device magnetometer at 300K indi cated that the twisted lattices in the wire significantly affected the anisotrop y of the nanowires due to the magnetoelastic effect, and consequently, the magne tic easy axis can be tuned to the longitudinal direction effectively.
The measurement of piezoelectric coefficient for PP cellular electret and the improvement of its piezoelectricity
Authors: Zhang Peng-Feng  , Xia Zhong-Fu  , Qiu Xun-Lin  , Wu Xian-Yong  ,   同济大学波耳固体物理研究所，上海  200092
Published: December 2020

In this paper, mechanical and dielectric parameters of virgin PP cellular film(t ype PQ50) were analyzed by dielectric resonance spectroscopy, and piezoelectric d33 coefficient of 18pC/N was measured. Up to 367pC/N of piezoelectric d33 coefficient for PP cellular electret was performed by means of pr essure-expansion techniques under the reasonable treatment conditions, which is about 20 times higher than that of famous ferroelectric polymer β-PVDF and whic h is higher than that of piezoelectric ceramic PZT. Based on scanning electron m icrograph and according to the piezoelectric theory model for PP cellular film t he structural and physical sources for high piezoelectric coefficient of these k inds of nonpolar porous film electret with space charge were discussed.
Investigation on the diamagnetic Faraday rotation spectra in Pr-substituted yttrium iron garnet
Authors: Zhang Guo-Ying  , Zhang Xue-Long  , Cheng Yong  , Xue Liu-Ping  , Han Kui  ,   (1)上海理工大学医疗器械学院,上海  200093; (2)中国矿业大学理学院,徐州  221008
Published: December 2020

By using the single particle model, the diamagnetic Faraday rotation (FR)spectra of Pr3+ ion in Pr:YIG crystal is presented based on the quantum theory. The linear dependence of λF-1/2θ on λ2 is calculated at 300 and 77K in the 105—13 micron wavelength range. It is found that the diamagn etic FR is 64% of paramagnetic FR at 77K and the two types of FR can be of more or less equal importance. The diamagnetic FR depends on the temperature and the exchange field for the ions with orbit single ground states derived from the cr ystal field.
A method to measure the beat frequency of weak light
Authors: Hou Yan-Xue  , Ma Hai-Qiang  , Wu Ling-An  ,   中国科学院物理研究所光物理实验室，北京  100080
Published: December 2020

A method is proposed for measuring the beat frequency of weak light based on pho ton correlation measurements. In contrast to conventional techniques this method is not limited by the response time of the detector or preamplifier, and can me asure frequencies on the order of 10GHz without the need of a frequency spectrum analyzer. Moreover, extremely low light intensities may be measured.
A new method to produce high spatial frequency grating with variable spacing
Authors: Zhu Hua-Feng  , Chen Jian-Wen  , Gao Hong-Yi  , Xie Hong-Lan  , Xu Zhi-Zhan  ,   中国科学院上海光学精密机械研究所强光光学重点实验室,上海  201800
Published: December 2020

In this article, a new method to produce gratings with linearly variable spatial frequency is proposed and the expression of grating frequency is obtained. By inserting special lenses into the two light paths, the production of grating with linearly variable spatial frequency is realized. The modification of frequency can be easily achieved by properly adjusting the experimental parameters. The simulated hologram is given.
Corner-pumped Yb:YAG lasers
Authors: Liu Qiang  , Gong Ma Li  , Li Chen  , Gong Wu-Peng  , Lu Fu-Yuan  , Chen Gang  ,   清华大学精密仪器与机械学系光子与电子技术研究中心，摩擦学国家重点实验室，北京   100084
Published: December 2020

A corner_pump method for high_power quasi_three_level lasers is reported. The de sign uses a slab laser configuration with the incident pump light from the slab corner. We present an analytic description of pumping absorption, pumping bright ness, doping concentration and crystal dimension for the corner_pumped composite Yb:YAG laser. In the experiments a maximum continuous-wave output power of 400 W with slope efficiency 28% was achieved. This result shows the validity of corn er_pumping concept and its feasibility in the development of high_power solid_st ate lasers.
Generation of two-photon entangled states through a cascaded nonlinear optical process in a quasiperiodic optical superlattice
Authors: Ji Ling-Ling  , Wu Ling-An  ,   中国科学院物理研究所光物理开放实验室，北京  100080
Published: December 2020

The search for new methods to produce entangled photons is a subject of great interest in quantum optics. We show theoretically that two_photon entangled states may be generated through a cascaded nonlinear optical process in a quasiperiodic optical superlattice. When an idler photon ωi produced from spontaneous parametric down conversion (ωp=ωs+ωi) combines with a pum p photon to produce a sum frequency photon ωb(ωb=ωi+ω p), the latter is entangled with the remaining signal photon ωi. Both a pulsed and a cw 532nm laser have been used to pump a quasi_phase matched LiTaO 3 crystal to generate simultaneously 630nm signal photons through parametric d own conversion and 460nm sum frequency photons. The advantage of this method is that entangled photons of short wavelength may be produced.
Sound field separation technique and its applications in near-field acoustic holography
Authors: Yu Fei  , Chen Jian  , Li Wei-Bing  , Chen Xin-Zhao  ,   合肥工业大学动态测试中心，合肥  230009
Published: December 2020

Sound field separation technique has been proposed, which overcomes the limitati on on applications of near_field acoustic holography (NAH). The limitation is th at the sound field on one side of holographic plane must be free，that is to say , all the sound sources must be confined to the other side. Sound field separation technique with double holographic planes has been built according to the wave field extrapolation theorem and the superposition theorem of sound pressure scalar in wave_number domain, and the technique with single holographic planes has also been built according to Euler's formulation and the vector superposition theorem of particle velocity in wave_number domain. A particular feature of the technique is that the influence of background noise on reconstructed results can be removed while retaining the background noise in the holographic measurements. The derivation of the principle verifies the technique theoretically, and the computer simulations and experiment demonstrate its feasibility and effectiveness.
Electronic theory for the refinement mechanism of ultrafine steel
Authors: Zhang Guo-Ying  , Liu Chun-Ming  , Zhang Hui  ,   (1)东北大学材料冶金学院，沈阳  110006; (2)沈阳师范大学物理科学与技术学院，沈阳  110034; (3)沈阳师范大学物理科学与技术学院，沈阳  110034;东北大学材料冶金学院，沈阳  110006
Published: December 2020

The model of 1/2［110］ edge dislocation in austenite phase was set up with comp uter programming. The environmentsensitive embedding energy (ESE) of C, N and alloy elements in grains or in the area of edge dislocation was calculated by us ing recursion method. The enrichment and interaction of C, N and alloy elements in the area of dislocation were discussed. Calculation results show that: discre te light impurities C and N tend to aggregate in the dislocation area, forming C aldwell air mass above the edge dislocation; the alloy element is liable to dist ribute in perfect austenite grains. Ti, V, Nb and Cr, which are strong or middli ng strong elements for carbide formation, are easy to aggregate in the edge disl ocation area. They can also form the Caldwell air mass above the edge dislocatio n like C or N. But Ni, which is non_carbide formation element, aggregates below the dislocation line or distributed in the perfect grains. The light impurity ca n enforce the aggregation of strong carbide forming elements in the edge disloca tion area. When the temperature is decreased, and when the concentration of C, N and alloy elements reach the high limit of concentration, the C, N compound of alloying elements will precipitate from the matrix in the edge dislocation area of austenite in the steel. These compounds can act as heterogeneous nuclei of au stenite phase in the course of recrystallization, leading to the refinement of a ustenite grains.
Monte Carlo simulation of optical emission spectra in electron assisted chemical vapor deposition of diamond
Authors: Wang Zhi-Jun  , Dong Li-Fang  , Shang Yong  ,   河北大学物理科学与技术学院,保定  071002
Published: December 2020

The optical emission spectra of atomic hydrogen, atomic carbon and radical CH in electron assisted chemical vapor deposition (EACVD) were studied by using the Monte Carlo simulation when CH4/H2 gas mixture was used as the input gases. Effects of the experimental parameters on emission spectra and synthesis of di amond films were investigated. The results obtained suggested that the CH radica ls should be considered as a precursor species for diamond deposition but atomic carbon C is not. The diamond growth rate may be enhanced by the substrate bias due to the changes of atomic hydrogen concentration and the increase of mean ele ctron temperature. A method of determining the mean temperature of electron was gained by using atomic hydrogen emission line, and the optimum experimental cond ition for diamond deposition was also obtained. These results are of great impor tance for depositing high_quality diamond films by controlling the conditions of technology efficiently.
Activation of the archaeal ion channel MthK is exquisitely regulated by temperature
Authors: Jiang Yihao , Idikuda Vinay , Chowdhury Sandipan , Chanda Baron
Published: December 2020

Physiological response to thermal stimuli in mammals is mediated by a structurally diverse class of ion channels, many of which exhibit polymodal behavior. To probe the diversity of biophysical mechanisms of temperature-sensitivity, we characterized the temperature-dependent activation of MthK, a two transmembrane calcium-activated potassium channel from thermophilic archaebacteria. Our functional complementation studies show that these channels are more efficient at rescuing K+ transport at 37°C than at 24°C. Electrophysiological activity of the purified MthK is extremely sensitive (Q10 >100) to heating particularly at low-calcium concentrations whereas channels lacking the calcium-sensing RCK domain are practically insensitive. By analyzing single-channel activities at limiting calcium concentrations, we find that temperature alters the coupling between the cytoplasmic RCK domains and the pore domain. These findings reveal a hitherto unexplored mechanism of temperature-dependent regulation of ion channel gating and shed light on ancient origins of temperature-sensitivity.
A statistical framework for assessing pharmacological responses and biomarkers using uncertainty estimates
Authors: Wang Dennis , Hensman James , Kutkaite Ginte , Toh Tzen S , Galhoz Ana ,   GDSC Screening Team, Lightfoot Howard , Yang Wanjuan , Soleimani Maryam , Barthorpe Syd , Mironenko Tatiana , Beck Alexandra , Richardson Laura , Lleshi Ermira , Hall James , Tolley Charlotte , Barendt William , Dry Jonathan R , Saez-Rodriguez Julio , Garnett Mathew J , Menden Michael P , Dondelinger Frank
Published: December 2020

High-throughput testing of drugs across molecular-characterised cell lines can identify candidate treatments and discover biomarkers. However, the cells’ response to a drug is typically quantified by a summary statistic from a best-fit dose-response curve, whilst neglecting the uncertainty of the curve fit and the potential variability in the raw readouts. Here, we model the experimental variance using Gaussian Processes, and subsequently, leverage uncertainty estimates to identify associated biomarkers with a new Bayesian framework. Applied to in vitro screening data on 265 compounds across 1074 cancer cell lines, our models identified 24 clinically established drug-response biomarkers, and provided evidence for six novel biomarkers by accounting for association with low uncertainty. We validated our uncertainty estimates with an additional drug screen of 26 drugs, 10 cell lines with 8 to 9 replicates. Our method is applicable to any dose-response data without replicates, and improves biomarker discovery for precision medicine.
Ecological adaptation in Atlantic herring is associated with large shifts in allele frequencies at hundreds of loci
Authors: Han Fan , Jamsandekar Minal , Pettersson Mats E , Su Leyi , Fuentes-Pardo Angela P , Davis Brian W , Bekkevold Dorte , Berg Florian , Casini Michele , Dahle Geir , Farrell Edward D , Folkvord Arild , Andersson Leif
Published: December 2020

Atlantic herring is widespread in North Atlantic and adjacent waters and is one of the most abundant vertebrates on earth. This species is well suited to explore genetic adaptation due to minute genetic differentiation at selectively neutral loci. Here, we report hundreds of loci underlying ecological adaptation to different geographic areas and spawning conditions. Four of these represent megabase inversions confirmed by long read sequencing. The genetic architecture underlying ecological adaptation in herring deviates from expectation under a classical infinitesimal model for complex traits because of large shifts in allele frequencies at hundreds of loci under selection.
Fruitless mutant male mosquitoes gain attraction to human odor
Authors: Basrur Nipun S , De Obaldia Maria Elena , Morita Takeshi , Herre Margaret , von Heynitz Ricarda K , Tsitohay Yael N , Vosshall Leslie B
Published: December 2020

The Aedes aegypti mosquito shows extreme sexual dimorphism in feeding. Only females are attracted to and obtain a blood-meal from humans, which they use to stimulate egg production. The fruitless gene is sex-specifically spliced and encodes a BTB zinc-finger transcription factor proposed to be a master regulator of male courtship and mating behavior across insects. We generated fruitless mutant mosquitoes and showed that males failed to mate, confirming the ancestral function of this gene in male sexual behavior. Remarkably, fruitless males also gain strong attraction to a live human host, a behavior that wild-type males never display, suggesting that male mosquitoes possess the central or peripheral neural circuits required to host-seek and that removing fruitless reveals this latent behavior in males. Our results highlight an unexpected repurposing of a master regulator of male-specific sexual behavior to control one module of female-specific blood-feeding behavior in a deadly vector of infectious diseases.
Illicit and Prescription Drug Misuse among Sexual Minority Women in the United States: A Protocol for a Scoping Review
Authors: Gagnon Kelly , Frankeberger Jessica , Corey Stephanie , Folb Barbara L. , Mair Christina , VonVille Helena , Coulter Robert W. S.
Published: December 2020

Background: The United States Institute of Medicine (IOM) published reports in 1999 and 2011 identifying drug use as a priority area for sexual minority health research, specifically focused on mechanisms contributing to drug use disparities and the development of tailored interventions. Limited research has prioritized sexual minority women (SMW) with the majority of substance use research among sexual minorities focused on adolescents and men who have sex with men. This scoping review will characterize the research literature related to illicit drug use and prescription drug misuse among SMW and sub-groups within the SMW population. Through this, we will identify: (1) specific substances used; (2) patterns of substance use; (3) risk and protective factors; (4) prevention interventions; and (5) drug treatment programs specific to SMW.

Methods/Design: This review will include studies with empirical data of illicit or prescription drug misuse among sexual minority women. Peer-reviewed quantitative research conducted in the United States and published in English from 2011-Present will be included. We will search Medline, PsycINFO, and Web of Science databases for relevant articles. Two independent reviewers will screen abstracts and relevant full-text studies for eligibility. Data will be extracted from eligible articles and results will be presented in narrative and tabular form as appropriate.

Discussion: This work will identify gaps of knowledge in the research pertaining to illicit or prescription drug misuse among sexual minority women since the 2011 US IOM report. As a result of this work, we will propose directions for future research to address identified gaps.
COVID-19 ja udmurdi pärimuskultuur
Authors:   Estonian Literary Museum, Estonia, Anisimov Nikolai ,   Udmurt Institute for Research in History, Language and Literature Udmurt Federal Reseach Centre of the Ural Section, Russian Academy of Sciences, Glukhova Galina ,   Institute of Udmurt Philology, Finno-Ugric Studies and Journalism, Udmurt State University, Russia
Published: December 2020

In this article, we examine the spring ceremonies, the Eastern Udmurt’s summer ceremonies, and the Udmurt holidays (the Great Day, the Day of the Plough, Easter, commemoration days, etc.) during the COVID-19 quarantine as well as the humorous songs and chastushkas inspired by the quarantine and self-isolation. This article is the first attempt to describe and characterise the influence of the pandemic on the example of the Udmurt traditional culture. In our analysis, we rely on internet posts, data transmitted by informants, articles in district papers as well as observations by the authors. The data allow us to evaluate the changes in Udmurt customs and people’s adaptation to critical situations. Self-isolation caused anxiety in many village dwellers, because it was not possible to party in real time and place. The internet posts confirmed that the Udmurt are happy to share preparations and proceedings of their feasts, they like to send congratulations to friends and kin, who are able to participate both in joyful and sad emotions. The humorous Udmurt songs and chastushkas posted on the Internet help to survive in the difficult situation in the republic due to the COVID-19 crisis.
Heategevus- ja solidaarsusmeditsiini problemaatikast Eesti näitel
Authors:   Estonian Literary Museum, Estonia, Kõiva Mare
Published: December 2020

Alternative, folk, and state medicine services intersect in the spheres of voluntary assistance and joint financing, donation medicine, charity movement, and solidary charity. Voluntary activity involves many people in different age groups and with different opportunities, and is wider than changes in lifestyle and an inherent turn to local activities and stances. The global trend remains in the transitional area of different domains, yet its deeply humane message, joint assistance to people in an emergency situation, constitutes the continuation of traditional means of assistance in today’s society. Charity medicine has opened up new topics for humanitarian studies. The article discusses the state and local institutions’ supportive activities for health care and, for example, for the coping strategies of people with severe health damage, as well as the support provided by different media channels for people with health issues, and voluntary help based on personal free will. The article focuses on the following questions: What is the status of solidarity in today’s medicine and welfare services? What are the characteristics, approaches, and results of charity medicine in Estonia? What questions are raised by charity? Do we deal with only medical and health issues or with human fractals?
Loomad Rootsi-aegse Tartu ülikooli meditsiinitöödes
Authors:   Research Centre of the University of Tartu Library, Estonia, Rein Kaarina
Published: December 2020

At the Swedish-period University of Tartu there were four medical works which described or mentioned animals in some connection. Animals were often used as metaphors in these works in order to draw parallels with humans. In this connection animals were rather considered to be inferior to humans as it was typical to the early modern period. In the medical works of the 17th century University of Tartu veterinary medicine is mentioned and also the use of animals as a source of remedies or even animals as their own doctors, teaching the humans how to heal certain diseases. There are hints to animals in scientific experiments. In the medical work Dissertatio prima de oeconomia corporis animalis, originating from 1698, the development of early modern physiology can be observed. There is a clear difference between the works which were compiled in the first half of the 17th century and the dissertation written at the end of the same century. The works that were written earlier were mostly based on ancient authors, whereas the dissertation from the end of the 17th century delivers empirical knowledge. Thus animals had their impact on the medicine of the 17th century University of Tartu as well as on the way of talking and writing about medicine.
Error curves for evaluating the quality of feature rankings
Authors: Slavkov Ivica , Petković Matej , Geurts Pierre , Kocev Dragi , Džeroski Sašo
Published: December 2020

In this article, we propose a method for evaluating feature ranking algorithms. A feature ranking algorithm estimates the importance of descriptive features when predicting the target variable, and the proposed method evaluates the correctness of these importance values by computing the error measures of two chains of predictive models. The models in the first chain are built on nested sets of top-ranked features, while the models in the other chain are built on nested sets of bottom ranked features. We investigate which predictive models are appropriate for building these chains, showing empirically that the proposed method gives meaningful results and can detect differences in feature ranking quality. This is first demonstrated on synthetic data, and then on several real-world classification benchmark problems.
Iterative improvement in the automatic modular design of robot swarms
Authors: Kuckling Jonas , Stützle Thomas , Birattari Mauro
Published: December 2020

Iterative improvement is an optimization technique that finds frequent application in heuristic optimization, but, to the best of our knowledge, has not yet been adopted in the automatic design of control software for robots. In this work, we investigate iterative improvement in the context of the automatic modular design of control software for robot swarms. In particular, we investigate the optimization of two control architectures: finite-state machines and behavior trees. Finite state machines are a common choice for the control architecture in swarm robotics whereas behavior trees have received less attention so far. We compare three different optimization techniques: iterative improvement, Iterated F-race, and a hybridization of Iterated F-race and iterative improvement. For reference, we include in our study also (i) a design method in which behavior trees are optimized via genetic programming and (ii)EvoStick, a yardstick implementation of the neuro-evolutionary swarm robotics approach. The results indicate that iterative improvement is a viable optimization algorithm in the automatic modular design of control software for robot swarms.
Trials in developing a nanoscale material for extravascular contrast-enhanced ultrasound targeting hepatocellular carcinoma
Authors: Wu Size , Lin Xiyuan
Published: December 2020

Background

Medical imaging is an important approach for the diagnosis of hepatocellular carcinoma (HCC), a common life threaten disease, however, the diagnostic efficiency is still not optimal. Developing a novel method to improve diagnosis is necessary. The aim of this project was to formulate a material that can combine with GPC3 of HCC for targeted enhanced ultrasound.

Methods

A material of sulfur hexafluoride (SF6) filled liposome microbubbles and conjugated with synthesized peptide (LSPMbs) was prepared and assessed in vitro and vivo. Liposome microbubbles were made of DPPC, DPPG, DSPE-PEG2000,and SF6, using thin film method to form shell, followed filling SF6, and conjugating peptide. A carbodiimide method was used for covalent conjugation of peptide to LSMbs.

Results

The prepared LSPMbs appeared round shaped, with size of 380.9 ±  176.5 nm, and Zeta potential of −51.4 ±  10.4mV. LSPMbs showed high affinity to Huh-7 cells in vitro, presented good enhanced ultrasound effects, did not show cytotoxicity, and did not exhibit targeted fluorescence and enhanced ultrasound in animal xenograft tumors.

Conclusion

Extravascular contrast-enhanced ultrasound targeted GPC3 on HCC may not be realized, and the reason may be that targeted contrast agents of microbubbles are hard to access and accumulate in the tumor stroma and matrix.
Possible Routes of Transmission and Precautions to be taken in Dental Practice from the Most Unwanted Evil COVID-19- A Review
Authors: Athkuri Srividya , Salagalla Udayaramya , Ravi Ravichandra , Borugadda Roopesh , Ponugubati Charishma Chowdary
Published: December 2020

Nosocomial infections are responsible for thousands of deaths worldwide every year which occur mainly because of virus exposure. One of such kind of infectious disease that has recently caused an outbreak is COVID-19 and a novel corona virus was its causative agent. It was declared as pandemic and emergency of international concern by WHO. Among the health care professions, dentistry has high risk of microbial infections either by direct/indirect contact or by atmospheric transmission. In order to limit the effects of virus diffusion infection control is an important step. Data was collected from electronic databases like PubMed, Medline, Scopus by entering the key words and all the relevant articles were collected and reviewed. The present review highlights the importance of preventing the virus transmission by possible methods of infection control procedures which should be followed during every step of a treatment procedure in a clinical practice.
Clinical Background and Detection of Chlamydia trachomatis Antigen among Infertile Women Attending University of Maiduguri Teaching Hospital, Nigeria
Authors: Kumurya A. S. , Usman M. , Sheriff S. J. , Ngabra H. , Umar M. A. , Abdulsalam A. , Nura A. , Askira M. U. , Haruna B. A.
Published: December 2020

Background: Chlamydia trachomatis infection is an established cause of pelvic inflammatory disease (PID), ectopic pregnancy, chronic pelvic pain and infertility among women. It is the most common bacterial sexually transmitted disease in the world. The infection is largely asymptomatic.

Aim: The study was carried out to determine the Clinical background as well as detect the Chlamydia trachomatis antigen among infertile women attending University of Maiduguri Teaching Hospital (UMTH).

Methods: A survey on the Clinical background and antigens to Chlamydia trachomatis was carried out among infertile and post natal women attending fertility Clinic UMTH. A total of 65 endocervical swab samples were collected from the aforementioned group of subjects within the age of 18-47 years, out of which 45 were collected from infertile women while the remaining 20 were obtained from post-natal women to serve as control subjects. The samples were analysed by using Chlamydia Rapid Test device swab/urine (Abon Biopharm(Hangzhou), Co., Ltd) that work on the principle of immunochromatographic technique.

Results: Highest number of infertility was observed on women within the age of 30-35 years (33.3%). The result shows that those that attained tertiary educational level have the highest number of infertility (60%). The study demonstrated highest number of infertility among female civil servants (53.3%) followed by full-time house wife (33.3%). More infertility was observed among women who are not engaged in the use of contraceptive measures (95.6%). The overall result from this study shows no prevalence (0.0%) of C. trachomatis genital infection among infertile women in UMTH.

Conclusion: Further research using more sensitive and specific procedures for the detection of C. trachomatis from clinical specimens such as nucleic acid amplification tests and cell culture are recommended among infertile women in Borno State, Nigeria.
Evaluation of Raffia Palm Weevil Larvae (Rhynchophorus phoenicis) as a Potential Biodiesel Resource
Authors: Tangka Julius K. , Esther Azemo F. , K. Boris Merlain Djousse
Published: December 2020

Ethical issues arise when arable agricultural land and heavy agronomic inputs are used to cultivate crops for energy production such as biodiesel. Alternative feedstocks for biodiesel production might solve the food energy competition scenario. White raffia larvae (Rhynchophorus phoenicis) appears as a credible option because of its high lipid content, a relatively short life cycle and its abundance in the tropical environment. This study investigated the use of R. phoenicis larvae for biodiesel production. R. phoenicis larvae was grown on raphia stipe for 21 days and used for crude grease extraction. The extracted crude grease was converted into biodiesel by acid-catalyzed esterification and alkaline-catalyzed trans-esterification. The physicochemical properties of crude grease and biodiesel were investigated using the European biodiesel standard (EN14214), and the American Society of Testing materials specifications. The defatted extraction residue was analyzed using the AOAC protocol. Results revealed that the cetane number, heating value, acid value and density of crude grease were found to be higher than those of rapeseed while kinematic viscosity and iodine values were smaller. The conversion yield of free fatty acids of crude grease into biodiesel reached 85%. The fuel properties of biodiesel obtained are quite comparable with those of EN 14214 and ASTM standard. The defatted extraction residue exhibited high protein content (66,76%) and mineral which make it suitable for animal and human feed supplement. Therefore, it was concluded that, the R. phoenicis larvae can be used as valuable feedstock for biodiesel production and animal feed resources.
Generating Distribution Functions Based on Burr Differential Equation
Authors: Momanyi Reinpeter Ondeyo , Ottieno J. A. M.
Published: December 2020

One of the most prominent families of statistical distributions is the Burr’s system. Recent renewed interest in developing more flexible statistical distributions led to the re-examination of Burr’s system. Solutions of Burr differential equation are expressed in terms of distribution functions. Burr [1] considered only 12 distribution functions known in literature as the Burr system of distributions, yet there are more than that in number. Studying the Burr system, it was realized that 9 of the Burr distributions are powers of cdf ′s, popularly now known as exponentiated distributions. The remaining 3 are direct solutions in terms of cdf′s. Detailed studies using generator approach techniques to generate Burr distributions has not been undertaken in literature. This motivated us to generalize solutions of Burr differential equation by generator approach. With this aim in mind, beta generator method, exponentiated generator method and beta-exponentiated generator method (a combination of beta and exponentiated generator methods) was proposed. However in this paper, we will focus on exponentiated generator technique as it generates cdf ′s. The other two generator approach techniques generate pdf′s and distributions of order statistics.
Hypo-magnesium and Hyperlipidemia Responsible for Hypertensive Status of Pregnant Women in Pakistani Population
Authors: Parveen Asia , Farooq Khan , Arshad Fatima , Mazhar Modasrah , Zahra Nureen , Sindhu Amira Saleem , Ali Qurban , Alam Rabail , Malik Arif
Published: December 2020

Background/ Aim: Pregnancy induced hypertension (PIH) has been a leading cause of maternal mortality worldwide. It could be responsible for several complications like hemodilution, altered lipid metabolism and deficiencies of different minerals in body. Although the causes of Pregnancy induced hypertension (PIH) remains indistinct. The aim of our present study was to evaluate the changes in magnesium serum levels and lipid profile in hypertensive and normotensive pregnant women.

Materials and Methods: An analytical case control study comprising 60 individuals was designed. From which 30 normotensive pregnant women served as control group (A) and 30 pregnancy induced hypertensive women served as case group (B). Patients with pre-existing hypertension were excluded.

Results: The independent t-test was used for comparison of various parameters between group A and B. Triacylglycerol (TAG) and low density lipoprotein cholesterol (LDL-C) levels were significantly high in PIH (B) as compare to normotensive group (A). Mean serum values of TG were measured as (195.73 ± 70.28 vs 156.27 ± 55.60 mg dL-1) and LDL-C vs control (87.33 ± 37.74 vs 69.45 ± 28.58 mg dL-1) in PIH and normotensive groups respectively. HDL-C in PIH vs Control (47.40±1.12 vs 54.43 ±1.27 mg dL-1) and Mg+2 PIH vs control (1.36±0.07 vs 1.94±0.35 mg dL-1) were measured respectively. High density lipoprotein cholesterol (HDL-C) and magnesium Mg+2 levels were significantly reduced in PIH.

Conclusion: The lower serum magnesium levels and abnormal lipids profile may indicate their possible role as risk factors in the development of PIH in pregnant women. Hence initial diagnosis of hypomagnesemia in PIH cases may help in minimizing the complications and development of new cure strategies.
Where is Nepal in the Food System Transition?
Authors: Sharma Manoj , Pudasaini Abhishek
Published: December 2020

In Nepal, 27% of GDP is contributed by the agriculture sector with 65.56% of households depending upon agriculture for employment. However, 51.8% of households are still food insecure and 25.2% are under the poverty line. Given these facts, it is interesting to watch how the economic growth and food system will go forward, despite the paradoxical history of development-modest growth but brisk poverty reduction has already been experienced. While literature noted that the transition to a food system is rapid for developing countries, very limited analysis linking the food system to its drivers and its consequences exists in the context of Nepal. The study examined food system transition using the secondary data from different sources and analyzing it through a conceptual framework of the food system. The study showed the contemporary food security issue is disparity in food access among the peoples driven by the poverty gap. The trends and scenarios shown in results revealed that the tendencies of food system drivers are on positive sides, but the structural foundation of agriculture (land issues, labor migration, mechanization, adaptations, etc.) is not so strong. This situation has created a serious question on the transition of the food system in Nepal. For this, the policy priorities are imperative to be institutionalized at all three levels of government-federal, state and local, and need to be concerted to transform the food system.
Targeted inhibition of ERα signaling and PIP5K1α/Akt pathways in castration‐resistant prostate cancer
Authors: Semenas Julius , Wang Tianyan , Sajid Syed Khaja Azharuddin , Firoj Mahmud AKM , Simoulis Athanasios , Grundström Thomas , Fällman Maria , Persson Jenny L.
Published: December 2020

Selective ERα modulator, tamoxifen, is well tolerated in a heavily pretreated castration‐resistant prostate cancer (PCa) patient cohort. However, its targeted gene network and whether expression of intratumor ERα due to androgen deprivation therapy (ADT) may play a role in PCa progression is unknown. In this study, we examined the inhibitory effect of tamoxifen on castration‐resistant PCa in vitro and in vivo. We found that tamoxifen is a potent compound that induced a high degree of apoptosis and significantly suppressed growth of xenograft tumors in mice, at a degree comparable to ISA‐2011B, an inhibitor of PIP5K1α that acts upstream of PI3K/AKT survival signaling pathway. Moreover, depletion of tumor‐associated macrophages using clodronate in combination with tamoxifen increased inhibitory effect of tamoxifen on aggressive prostate tumors. We showed that both tamoxifen and ISA‐2011B exert their on‐target effects on prostate cancer cells by targeting cyclin D1 and PIP5K1α/AKT network and the interlinked estrogen signaling. Combination treatment using tamoxifen together with ISA‐2011B resulted in tumor regression and had superior inhibitory effect compared with that of tamoxifen or ISA‐2011B alone. We have identified sets of genes that are specifically targeted by tamoxifen, ISA‐2011B or combination of both agents by RNA‐seq. We discovered that alterations in unique gene signatures, in particular estrogen‐related marker genes are associated with poor patient disease‐free survival. We further showed that ERα interacted with PIP5K1α through formation of protein complexes in the nucleus, suggesting a functional link. Our finding is the first to suggest a new therapeutic potential to inhibit or utilize the mechanisms related to ERα, PIP5K1α/AKT network, and MMP9/VEGF signaling axis, providing a strategy to treat castration‐resistant ER‐positive subtype of prostate cancer tumors with metastatic potential.
Anakinra usage in febrile infection related epilepsy syndrome: an international cohort
Authors: Lai Yi‐Chen , Muscal Eyal , Wells Elizabeth , Shukla Nikita , Eschbach Krista , Hyeong Lee Ki , Kaliakatsos Marios , Desai Nevedita , Wickström Ronny , Viri Maurizio , Freri Elena , Granata Tiziana , Nangia Srishti , Dilena Robertino , Brunklaus Andreas , Wainwright Mark S. , Gorman Mark P. , Stredny Coral M. , Asiri Abdurhman , Hundallah Khalid , Doja Asif , Payne Eric , Wirrell Elaine , Koh Sookyong , Carpenter Jessica L. , Riviello James
Published: December 2020

Febrile‐infection related epilepsy syndrome (FIRES) is a devastating neurological condition characterized by a febrile illness preceding new onset refractory status epilepticus (NORSE). Increasing evidence suggests innate immune dysfunction as a potential pathological mechanism. We report an international retrospective cohort of 25 children treated with anakinra, a recombinant interleukin‐1 receptor antagonist, as an immunomodulator for FIRES. Anakinra was potentially safe with only one child discontinuing therapy due to infection. Earlier anakinra initiation was associated with shorter duration of mechanical ventilation, ICU and hospital length of stay. Our retrospective data lay the groundwork for prospective consensus‐driven cohort studies of anakinra in FIRES.
Environment‐Responsive Lipid/siRNA Nanoparticles for Cancer Therapy
Authors: Lu Zheng‐Rong , Laney Victoria E. A. , Hall Ryan , Ayat Nadia
Published: December 2020

RNA interference (RNAi) is a promising technology to regulate oncogenes for treating cancer. The primary limitation of siRNA for clinical application is the safe and efficacious delivery of therapeutic siRNA into target cells. Lipid‐based delivery systems are developed to protect siRNA during the delivery process and to facilitate intracellular uptake. There is a significant progress in lipid nanoparticle systems that utilize cationic and protonatable amino lipid systems to deliver siRNA to tumors. Among these lipids, environment‐responsive lipids are a class of novel lipid delivery systems that are capable of responding to the environment changes during the delivery process and demonstrate great promise for clinical translation for siRNA therapeutics. Protonatable or ionizable amino lipids and switchable lipids as well as pH‐sensitive multifunctional amino lipids are the presentative environment‐responsive lipids for siRNA delivery. These lipids are able to respond to environmental changes during the delivery process to facilitate efficient cytosolic siRNA delivery. Environment‐responsive lipid/siRNA nanoparticles (ERLNP) are developed with the lipids and are tested for efficient delivery of therapeutic siRNA into the cytoplasm of cancer cells to silence target genes for cancer treatment in preclinical development. This review summarizes the recent developments in environment‐response lipids and nanoparticles for siRNA delivery in cancer therapy.