bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application and exploration of virtual simulation experimental platform in the experimental teaching of clinical testing instruments and techniques
Authors: Peng Yucheng , Huo Yishan , Madinaimu Abibula , Lv Jie , Feng Yangchun , Yang Jia , Qiao Wenbin , Guo Fan , Cheng Zhenzhen , Ma Xiumin 
Published: May 2023

Clinical laboratory instrumentation and technology is a multidisciplinary, multi-technology, multi-disciplinary cross-discipline, with strong application, theoretical and experimental teaching methods are single and boring, and it is difficult for students to master and understand the abstract content. The laboratory has cooperated with a company to complete the experimental teaching for undergraduate students, and analyzed the advantages of this teaching method and the problems that need to be solved through the questionnaire and formative evaluation, and analyzed and summarized them, so as to provide relevant experience for this kind of courses to adopt the virtual simulation experimental platform and provide directional guidance for the construction and development of the virtual simulation experimental platform.
Clinical laboratory instrumentation and technology is a multidisciplinary, multi-technology, multi-disciplinary course, which is highly applied, rapidly developing, and has a short update cycle, and is one of the main professional courses in medical laboratory technology.
Since the epidemic in 2020, universities across the country have been actively responding to the call of the Ministry of Education to "suspend classes without stopping school" and adopting various teaching methods such as online teaching, catechism teaching, virtual simulation teaching, etc. As a new applied subject course with a high degree of knowledge and technology intensity and a unique application goal, Clinical Laboratory Instruments and Technology has undergone After nearly three years of continuous integration and exploration, our teaching and research department is currently using Shandong Zezhong virtual simulation platform to conduct laboratory classes, replacing the online teaching method adopted by most institutions, and improving teaching quality and implementing teaching reform by continuously developing the teaching mode of this course. In accordance with the spirit of document [2001] No. 4 of the Ministry of Education, combined with the teaching requirements of this course and the construction standards of the national high-quality courses, constantly adhere to the development and practice of the teaching methods of the course, the reform and innovation of teaching methods, so that it can adapt to the teaching needs of the current situation is the focus of this paper.
Setting parameters for developing undergraduate expertise in transdisciplinary problem solving at a university-wide scale: a case study
Authors: Bammer Gabriele , Browne Chris A. , Ballard Chris , Lloyd Natalie , Kevan Alison , Neales Nicholas , Nurmikko-Fuller Terhi , Perera Sean , Singhal Isha , van Kerkhoff Lorrae 
Published: May 2023

AbstractAs part of a curriculum reform process, The Australian National University (ANU) is introducing a universal undergraduate requirement that responds to decades-long calls for universities to take seriously the development of expertise in the transdisciplinary problem solving required to address the major challenges facing society. Described here are the process and outcomes of the deliberations of the working group tasked with setting parameters for the implementation of this expertise. The working group identified relevant context, including that the requirement has to work for all of the University’s 13,000 undergraduate students, allowing them to tailor coursework in transdisciplinary problem solving according to their disciplinary choices, personal interests and career aspirations. The expertise is to be developed in existing and new courses, featuring small classes with flexible interactive delivery and should build on the University’s comprehensive coverage of academic disciplines and fields, along with the university’s strong track records in transdisciplinary research and education. The working group developed an ANU framework for transdisciplinary problem solving, focused on the following six characteristics: change-oriented, systemic, context-based, pluralistic, interactive and integrative. How these characteristics can be translated into learning outcomes is demonstrated, along with relevant ways of teaching. The working group highlighted two key challenges that those involved in the mechanics of the implementation will have to deal with and proposed a way forward for the first of them. One is for students to be able to readily identify relevant courses. The working group proposed a tag-and-points system, with the ‘tag’ identifying courses relevant to transdisciplinary problem solving and ‘points’ indicating the number of characteristics covered and the depth of that coverage. The second challenge is coordination across courses to minimise duplication and maximise the opportunity to keep building skills. The paper concludes by summarising key areas that may be useful to others deliberating on the expertise required for university graduates to effectively contribute to addressing societal challenges, as well as how universities can best foster the development of that expertise.
Plasmon-enhanced photodetectors fabricated using digital inkjet-printing on chemically nanopatterned silicon wafers
Authors: Guo Xiaohang , Banerjee Debika , Asuo Ivy M. , Fortier Francois-Xavier , Slimani Moulay Ahmed , Cloutier Sylvain G. 
Published: May 2023

In this study, we have fabricated and characterized three different configurations of photodetectors with digital inkjet printing techniques on different types of silicon substrates, such as pristine n-type silicon and chemically nanostructured n-type silicon, with and without Ag nanoparticle-induced surface-plasmon enhancement. Among these three comparison batches, digitally printed devices on chemically nanostructured n-type silicon with Ag nanoparticle-induced enhancement yield the highest photocurrent enhancement factor of 920×, the lowest rise and decay times of τr = 176 ms and τd = 98 ms, respectively, and the highest responsivity of 24.8 mA W−1 at wavelengths ranging from 380 to 700 nm. Most importantly, we demonstrate that these devices are highly stable after fabrication, losing less than 3% of their efficiency over 60 days under ambient conditions. We firmly believe that this simple device architecture and effective digital fabrication process are most promising for the realization of efficient, stable, and low-cost photodetectors fabricated at large scales.
Measuring epitaxial graphene nanoribbons with low-frequency alternating current
Authors: Yeh C.-C. , Mhatre S. M. , Tran N. T. M. , Hill H. M. , Jin H. , Liao P.-C. , Patel D. K. , Elmquist R. E. , Liang C.-T. , Rigosi A. F. 
Published: May 2023

We have demonstrated the fabrication of both armchair and zigzag epitaxial graphene nanoribbon (GNR) devices on 4H–SiC using a polymer-assisted sublimation growth method. The phenomenon of terrace step formation has traditionally introduced the risk of GNR deformation along sidewalls, but a polymer-assisted sublimation method helps mitigate this risk. Each type of 50 nm wide GNR is examined electrically and optically (armchair and zigzag), with the latter method being a check on the quality of the GNR devices and the former using alternating current to investigate resistance attenuation from frequencies above 100 Hz. Rates of attenuation are determined for each type of GNR device, revealing subtle suggested differences between armchair and zigzag GNRs.
Preliminary design of helicon plasma thruster by means of particle swarm optimization
Authors: Coppola G. , Panelli M. , Battista F. 
Published: May 2023

Radio-frequency and Helicon Plasma Thrusters have emerged as viable electric propulsion systems due to their high plasma density, thrust density, and useful life. Helicon Plasma Thruster (HPT) is a very attractive technology because it could use many propellants and does not require hollow cathodes or grids, overcoming their associated critical erosion problem and extending the thruster’s lifetime to some tens of thousands of hours. Despite the fact that high-power HPTs have reached 30% efficiency in laboratory configurations, sophisticated numerical models are required for a deeper understanding of the main plasma phenomena and for the preliminary design to increase the very low HPT’s efficiency (3–7%) typical of the low-power class thrusters. The paper focuses on the development of a model for the low-medium power range (50–2000 W) of HPTs design. Starting from Lafleur’s model, it has been improved with the hypothesis of neutral gas being expelled at the real thruster’s wall operative temperature (300–600 K) in place of the more frequent laboratory temperature assumption (300 K). This hypothesis affects total thrust and specific impulse by about 10%. A parametric analysis of the slenderness ratio (chamber length-to-radius) has been conducted. The results showed that slender configurations lead to higher efficiencies. Downstream from the numerical model validation, a tool for the global design has been built with the Particle Swarm Optimization (PSO) technique that leads to optimal thruster configuration. This tool has been used to design a 4 mN HPT tuning the PSO in order to minimize the dimensions and the weight according to the assigned mission constraints (i.e., power, thrust, and weight). A total efficiency of 10.4% results.
Languages and language contact in China
Authors: Bao Zhiming , Shen Ruiqing , Han Kunmei 
Published: May 2023

AbstractChina is ethnically and linguistically diverse. There are 56 officially recognized ethnic groups in the country, including the majority Han, with a 1.2 billion-strong population and Tatar, the smallest minority group with only 3,556 people residing in Xinjiang, according to the 2010 Population Census of the People’s Republic of China, the latest census data available on the government’s website (www.stats.gov.cn). The Han accounts for 91.6% of the population, with the minorities taking up the balance of 8.4%. Most ethnic groups have their own languages, which fall into typologically distinct language families, the largest being Altaic and Sino-Tibetan.Ethnologuelists 299 languages in China and rates the country 0.521 in linguistic diversity, compared with 0.035 for Japan and 0.010 for South Korea (Simons & Fennig 2017). A few ethnic groups, such as the Hui (Chinese Muslims) and the Manchus, who founded the last imperial dynasty of Qing (1644–1912), have lost their indigenous languages over the centuries. They speak the language of the Han majority.Linguistic diversity in China is manifested in two ways: across the ethnic groups and within the Han majority. In what follows, we give a schematic description of the languages and briefly summarize the papers in this issue that offer a snapshot of language contact in China.
Electrical properties of a generalized 2 × n resistor network
Authors: Zhou Shi , Wang Zhi-Xuan , Zhao Yong-Qi , Tan Zhi-Zhong 
Published: May 2023

Abstract
Any changes in resistor conditions will increase the difficulty of resistor network research. This paper considers a new model of a generalized 2 × n resistor network with an arbitrary intermediate axis that was previously unsolved. We investigate the potential function and equivalent resistance of the 2 × n resistor network using the RT-I theory. The RT-I method involves four main steps: (1) establishing difference equations on branch currents, (2) applying a matrix transform to study the general solution of the differential equation, (3) obtaining a current analysis of each branch according to the boundary constraints, and (4) deriving the potential function of any node of the 2 × n resistor network by matrix transformation, and the equivalent resistance formula between any nodes. The article concludes with a discussion of a series of special results, comparing and verifying the correctness of the conclusions. The work establishes a theoretical basis for related scientific research and application.
Saturable absorber based on tapered graded-index multimode fiber with ZnO coating for bound solitons generation
Authors: Jin N M , WANG D N , Cai S L , Peng Y Q , Chen H F 
Published: May 2023

Abstract
A passively mode-locked erbium-doped fiber laser with a saturable absorber (SA) based on a tapered graded-index multimode fiber with zinc oxide coating is proposed and demonstrated in this paper. The device is also a platform supporting various types of solitons outputs. The conventional solitons with center wavelength of 1558.86 nm, pulse width of 537 fs, and signal-to-noise ratio of 61.27 dB are generated at the repetition frequency of 18.37 MHz. By adjusting the polarization controller and increasing pump power, tightly and loosely bound solitons and two-fold solitons can be generated. The pulse trains of tightly bound solitons exhibit the separation of 1.91 ps, the pulse width of ∼707 fs, and centered at 1560 nm, whereas the pulse separation of loose bound solitons is 18.06 ps. Such a SA is easy in fabrication and highly stable in operation and can enrich the exploration of multi-soliton complexes.
Ultra-short laser structuring of 3D-microfabricated non-resorbable polystyrene polymer to anchor cellular adhesion
Authors: Angelova L , Filipov E , Aceti D M , Zhelyazkova Al , Buchvarov I , Daskalova A 
Published: May 2023

Abstract
Tissue engineering is emerging as a preferred choice for regeneration of irreversible bone tissue defects. It’s main “weapons” are the artificially created biocompatible three-dimensional cellular matrices that mimic the extracellular matrix’s structure and provide a mechanically stable inert substrate for the natural growth of cells. These porous scaffolds provide sufficient inner surface for cell adhesion, migration, proliferation and protrusion “inside” the temporal implant, facilitating in that way the natural bone ingrowth and vascularization. This leads, eventually, to overgrowing the outer and inner surface of the biomimetic implant with recipient self-formed bone tissue, thus avoiding a possible immune response.
In the current study 3D Polystyrene (PS) non-resorbable synthetic cellular bone scaffolds, produced by 3D microfabrication technology, were additionally structured by applying femtosecond (fs) laser radiation with variable parameters thus achieving optimal laser processing conditions, for creation of 3D matrix with enhanced fiber surface properties. The main aim is the establishment of surface structured microporous biomimetic scaffolds, providing improved cell adhesion, infiltration and formation of extracellular matrix. The 3D laser functionalized PS samples were investigated by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray analysis (EDX), confocal (optical profilometer) and roughness analyses for evaluation of their morphological and chemical properties before and after fs structuring was performed. Water contact angle (WCA) evaluation was also conducted. Future experimental work will include in vitro cellular studies for determining the optimal structuring laser parameters, providing osteoconductive and osteoinductive qualities of the 3D fs-microstructured PS scaffolds.
DFT simulation of the Raman spectrum of single layer graphene
Authors: Kolev S K , Trifonov D V , Aleksandrov H A , Atanasov V A , Popov V N , Milenov T I 
Published: May 2023

Abstract
Raman spectroscopy is one of the most suitable tools for studying few-layer graphene. The position of the G band and the defect-induced D and D' bands in the spectra of perfect single-layer graphene with sp2-hybridized carbon atoms and hydrogenated graphene with 27.7% sp3-hybridized carbon atoms are simulated using the Density Functional Theory (DFT) method with Perdew-Burke-Ernzerhof (PBE) functional. In the case of perfect graphene, the Raman G band is predicted at 1612 cm-1. In the case of the hydrogenated structure, a new feature appears. Namely, along with the G band, now shifted to 1591 cm-1, an additional feature, located at 1703 cm-1, is clearly seen. The latter is due to oscillations, involving six atomic benzene rings, containing two sp3-hybridized C atoms. According to our results, the presence of defects, related to sp3 hybridized carbon, gives rise to the appearance of the defect D' band in the Raman spectrum of defective graphene. This study shows that it is possible to simulate Raman spectra using the DFT method, with the results qualitatively matching the experimental data.
Diffraction-limited high-power master oscillator – power amplifier system oscillating in visible spectral range on copper atomic transitions for precise material micromachining
Authors: Kostadinov I K , Temelkov K A , Popova L T , Slaveeva S I , Yankov G P 
Published: May 2023

Abstract
A new considerably improved master oscillator–power amplifier copper bromide vapor system delivering diffraction-limited high-power laser radiation at the atomic copper 510.6- and 578.2-nm lines is developed and investigated. The highest beam quality achieved so far with laser systems oscillating on the metal self-terminating transitions is confirmed by two independent methods. Precise micromachining is realized on silica, ceramics, silicon, and stainless steel. Though the aspect ratio of the crater drilled in optical grade fused quartz through the wave-guide-assisted method is higher than the one obtained so to date, a new method is also developed to make the aspect ratio almost limitless.
Modification of microcrystaline graphites by pulsed laser ablation in a flow mode suspension
Authors: Dimov D A , Stankova N , Karaivanova D , Karashanova D , Georgieva B , Avramova I , Petrov M , Valcheva E , Avdeev G , Ivanov K , Milenov T 
Published: May 2023

Abstract
Here we present experimental results on the modification of graphite suspensions in bi-distilled water by laser irradiation in a flow mode system. The fundamental wavelength of a Nd:YAG laser system (λ= 1064 nm) was used in our experiments. The morphology of the sedimented and dried powders was studied by transmission electron microscopy (TEM). Their phase composition and structure were explored by Raman spectroscopy, GIXRD, as well as TEM.
SERS active substrates for neonicotinoids studies
Authors: Atanasov P A , Nedyalkov N N , Dikovska A O , Fukata N , Jevasuwan W 
Published: May 2023

Abstract
Different basic substrates, – Si wafers, (001) SiO2, printer paper, Al2O3, micro-processed (001) SiO2 or diamond abrasive films, have been used to create active Ag and Au nanostructures. In this lecture, we report the use of pulsed-laser deposition and thermal deposition both followed by pulsed-laser annealing; the results are compared. Advanced substrates of Au and Ag on Si were produced in view of surface-enhanced Raman spectroscopy (SERS) detection of the imidacloprid (Nuprid 200 SP) neonicotinoid insecticide in amounts much smaller than those ordinarily applied in agricultural medicine. The SERS peaks intensity rose by at least one order of magnitude after the pulsed-laser annealing of the metal films and nanoparticles arrays formation. The enhancement factor (EF) was estimated to be >5×104, the limit of detection (LOD) reached being < 0.5 nM. The properties of the advanced substrates were compared and discussed. The importance of SERS as a relatively inexpensive and simple method is emphasized in regulating, monitoring and controlling the level of such chemicals as environmental pollutants, thus precluding harming the human and, especially, honey bees’ health.
Laser-assisted synthesis of metallic composite nanostructures in aqueous solutions
Authors: Stankova N E , Nikolov A , Karashanova D , Nedyalkov N , Dikovska A 
Published: May 2023

Abstract
The method of pulsed laser ablation in liquids (PLAL) is applied for synthesis of composite nanostructures on the basis of TiOx and ZnO combined with noble metals like Au, Pt and Pd. The metallic plate immersed in water is laser ablated by nanosecond Nd:YAG pulsed laser irradiation. Its fundamental wavelength and the fourth harmonic are used, respectively, to produce and to modify the morphology and structure of the nano-objects. The synthesis procedure consists of two consecutive steps: laser ablation of the selected metal targets followed by unfocused laser beam irradiation of the initial colloids of nanostructures. The phase composition, structural and the shape and size morphological features were assessed by analytical method – transmission electron microscopy (TEM) in its main modes – Bright Field TEM (BF TEM), High Resolution TEM (HRTEM) and Selected Area Electron Diffraction (SAED). Formation of bimetallic polycrystalline alloys and Pt/Ti(TixOy) and Pd/Ti(TixOy) core-shell nanoparticles was founded.
Fluorescent study of wastewater and the effect of low quantity of disinfectant
Authors: Tsonkov L , Georgieva D , Vladimirova – Mihaleva L , Slavova V , Mihalev M 
Published: May 2023

Abstract
In the last few years due to the COVID-19 pandemic the pollution with large quantities of medicaments, disinfectants and essential oils raised the importance of their detection in wastewater. The research of new techniques for diagnostics continues. Some promising methods for finding contaminators of different origin are based on the optic and spectral characteristics of the examined water. Those could be used in determining the exact pollutant. The spectroscopic examination could also be conducted real-time under in vivo conditions. In this research, we use fluorescence spectroscopy to investigate the purity of water probes from the discharge of the Iskar River near the treatment plant in Samokov (Bulgaria) and the influence of small amounts of disinfectants (ethanol). The results show that fluorescence can be used to determine the purity of water probes and little amounts of alcohol in wastewater.
Applications of single laser pulse from Nd:doped lasers for cleaning of small diameter carious lesions. Modelling and analytical study
Authors: Uzunov T , Deneva M , Uzunova P , Nenchev M 
Published: May 2023

Abstract
We report on an analytical study with physical modelling, some additional experimental studies and computer programming of the cleaning of initial carious lesions (1 - 3 mm in diameter) with a single laser pulse from Nd:doped (Nd:YAG and Nd:Glass) lasers (wavelength 1.06 μm). The analysis is based on experimental data from our preliminary study and aims to develop a method to predetermine the necessary laser pulse parameters for reasonable cleaning. To obtain such laser pulse parameters, we considered the conversion of light energy into heat, the propagation of incident light and the resulting heating of the dental tissue, the induced ablation processes associated with lesion cleaning, and the formation of the necessary hole in combination with acceptable heating of the pulp chamber and prevention of enamel crack formation. Cleaning is naturally associated with the bactericidal effect. The study, except for the estimation, confirms that the use of single light pulses of the considered lasers with energies from 1.3 to 4.5 J, densities from 40 to 120 J/cm2, pulse duration from a few hundred microseconds to ~2 ms (i.e., in the simplest, natural, free mode of operation of the noted lasers) can be considered as a promising method to start caries treatment.