bluuebunny/crossref_metadata_2025 huggingface dataset:
NSERC USRA Research Paper
Authors: Stewart Kalle
Published: August 2023

This research paper discusses the comprehensive exploration of adaptive and non-adaptive control systems utilizing Quanser's QCar platform. The study covers real-time computational capabilities, real-time computer vision techniques, and the educational potential of Quanser's QCar. The resulting systems – Adaptive Lane Following, Sign Detection, Traffic Light Detection, and Adaptive Cruise Control – showcase their effectiveness across diverse driving scenarios and environmental conditions.
The research methodology involves distinct phases, starting with an Initial Onboarding Process. Familiarity with software platforms such as Simulink, ROS, Python, and more was essential. Understanding the QCar platform was facilitated through User Manuals and predeveloped Simulink documentation. In-depth studies in Autonomous Technology and Computer Vision informed system development. A structured approach encompassing Research, Planning, Development & Testing stages was followed. Research gathered insights from repositories, videos, research papers, and websites. This also involved creating final testing environments to simulate various lighting conditions which were called daytime, afternoon, and nighttime environments. This allowed for the QCar’s performance to be effectively evaluated and compared against each other.
The Adaptive Lane Following system tackles fluctuating lighting conditions using adaptive thresholding for consistent lane tracking. The Sign Detection System identifies stop signs, serving as a foundation for more complex systems. The accurate Traffic Light Detection system enables safe navigation. The ACC and Object Detection system enhances QCar's safety in dynamic traffic.
The study effectively combines theory with practical implementation, exploring both adaptive and non-adaptive control systems. The developed systems showcase capabilities across different scenarios. Additional potential research directions include Python threading, audio features, GPS Track Network, and ROS optimization. This research mainly contributes to educational autonomous vehicle innovation and development.
Numerical and Experimental Analyses of Track Shoe Patterns for Vehicle on Sandy Terrain
Authors: Nurprasetio Ignatius Pulung , Wicaksana Wirya , Zulaikah Siti , Budiman Bentang Arief
Published: August 2023

A track is a vehicle propulsion system that consists of a continuous band of chains connected with track shoes or may be entirely made of rubber. The track system is still commonly used on various vehicles, including bulldozers, excavators, tanks, and tractors, and has recently been used in lunar expedition vehicles. A tracked vehicle is mainly designed to provide better mobility in rough, uneven, or slippery terrain. The main component of the track system is track shoes or so-called grousers. This track shoe geometry will determine the tractive performance of the vehicle. If an incorrect shape is used, the excavator will most likely slip. The previous study approached this traction problem by using the semi-empirical method. However, until now, the track geometry and traction relation are still unclear. This research focuses on the effects of track shoe geometry on tractive performance and vehicle climbing ability. The analysis was mainly conducted with a DEM (Discrete Element Method) simulation. The result from the experimental test is also confirmed using a small-scale RC prototype on simulated terrain with different slope variations. It is proven that the grouser height directly affects the climbing performance of tracked vehicles. A higher grouser height proves to be better at a higher inclination slope. However, for a low inclination angle, the flattened track was better. The traction result from the EDEM simulation also yields a similar result. However, higher usable traction means more friction is generated; therefore, the track with higher traction also takes more energy to cover the same distance.
Clustering Mining Equipment Productivity Data Using K-Means Algorihtm
Authors: Ikhsan Yahmid Muh Sandi Arista , Chen Tony , Try Muhammad Emirat Millenium , Silangin Karno Nugroho , Putri Nurul Alifia , Anas Aryanti Virtanti
Published: August 2023

There are many factors that affect the productivity of mining equipment, one of which is the condition of the mining equipment when it is used. Knowing the condition of the machines on mining equipment is mandatory for supervisors in mining activities. In analyzing data on the condition of mining equipment in large quantities requires a lot of energy and time, so a classification model is needed that can categorize the mining equipment based on its performance. Data Mining is a process that uses statistical, mathematical, artificial intelligence and machine learning techniques to extract information. The results of data mining for mining productivity data are obtained duration of mining equipment work has a impact on productivity based on correlation value between work duration and maintenance duration of a tool. Data mining analysis is also carried out by clustering mining equipment using the K-Means model. The results obtained a conclusion that supports mining equipment with less working duration affects to productivity. The result shows variables that affect the productivity of mining equipment and divide mining equipment categories based on tool performance with data mining clustering techniques.
Natural Frequencies of Isotropic Rectangular Plates in Improved Accuracy
Authors: Narita Yoshihiro
Published: August 2023

The objective of this paper is to present comprehensive lists of accurate natural frequencies of isotropic thin rectangular plates. For this purpose, a simple yet very accurate analytical approach is described to study the free vibration of the plates. In numerical computations, convergence and comparison studies are conducted to check accuracy of the present solution and to demonstrate improvement of numerical solutions in the results. Twenty-one tables are then provided to give the lowest six frequency parameters for all possible combinations of three typical edge conditions (clamped, simply supported and free edges). Each frequency value in the tables is given in five significant figures for non-Levy type problem (i.e., two opposite edges not simply supported) and six significant figures for Levy type problem. These results are presented for five different aspect ratios in the same format of the past representative reference.
Development of Vibration Measurement System using a Microcontroller
Authors: Sekine Koji , Hayakawa Keigo
Published: August 2023

It is important to interpret resonance in the design to reduce the vibration of mechanical structures, and to verify this resonance phenomenon by experiments and theoretical approach. When the vibration of a continuous system is observed using a vibration system, the experience and skill of the observer affect the measurement accuracy of the natural frequency and vibration modes. Therefore, in this study, a vibration measurement system is developed to stably and quantitatively verify the natural vibration of the beams using a microcontroller and an ultrasonic sensor. The vibration measurement system consists of a microcontroller, a vibration motor and an ultrasonic sensor. The accuracy and validity of the natural frequencies of the beams measured by the system are discussed, and the performance of present system is evaluated on the basis of the measurement results of the natural frequencies and the natural vibration waveforms.
The Effect of Spot Welding Parameters for Dissimilar Material Mild Steel and Galvanizes Steel on Nugget Size and Mechanical Strength
Authors: Hayat Azwar Azwar , Al Muslim La Ode , Aminy Ahmad Yusran
Published: August 2023

The objective of this research was to analyze the effect of spot welding parameters on the size of the weld nugget and the maximum shear strength on dissimilar material mild steel and galvanized steel. The Taguchi and ANOVA methods were used to determine the welding parameters’ contribution to joint quality. Experimental design using Minitab-19 software with Taguchi method of 3 level 3 factor with L27 runs. Specimen size and dimensions were made using ASTM D1002 standard, with a plate thickness of 0.8 mm. Taguchi analysis S/N ratio data mean for weld nugget diameter with three levels of current used, 4 kA, 6 kA, and 8kA, shows the most influential on the diameter of the weld nugget was at 8 kA. The three levels of welding time used, 2s, 4s, and 6s, show the most influential on the diameter of the nugget the weld was at the third level for 6 seconds. It found that there was no significant difference in the size nugget at the three electrode pressure levels of 30 Ppsi, 40 Psi, and 50 Psi. Based on the tensile test and Taguchi analysis, the lowest shear strength was found in a weld nugget size of 3.15 mm at a welding current of 4 kA, a welding time of 2 seconds, an electrode pressure of 30 Psi, with a shear tensile strength of 300.19 N. Along with an increase in the size weld nugget correlated to an increase of shear strength. The highest shear tensile strength was found in the nugget size of 4.16 mm, with a welding current of 8 kA, welding time of 2 seconds, electrode pressure of 50 Psi, with a shear tensile strength of 3383.43 N. From the ANOVA, it found that the three factors of spot welding parameters were used, the most influential parameter in the formation of weld nuggets was welding current with a contribution of 84.86% then followed by welding time with a contribution of 14.86% and electrodes force with a contribution of 0.13%. Then from the three factors of spot welding parameters that were used the most influential parameter on the maximum shear tensile strength was the welding current with a contribution of 95.86 % then followed by welding time with a contribution of 0.52% and electrodes force with a contribution of 0.05%.
An Embedded Convolutional Neural Network for Maze Classification and Navigation
Authors: Dewantoro Gunawan , Hadiyanto Dinar Rahmat , Febrianto Andreas Ardian
Published: August 2023

Traditionally, the maze solving robots employ ultrasonic sensors to detect the maze walls around the robot. The robot is able to transverse along the maze omnidirectionally measured depth. However, this approach only perceives the presence of the objects without recognizing the type of these objects. Therefore, computer vision has become more popular for classification purpose in robot applications. In this study, a maze solving robot is equipped with a camera to recognize the types of obstacles in a maze. The types of obstacles are classified as: intersection, dead end, T junction, finish zone, start zone, straight path, T–junction, left turn, and right turn. Convolutional neural network, consisting of four convolution layers, three pooling layers, and three fully-connected layers, is employed to train the robot using a total of 24,000 images to recognize the obstacles. Jetson Nano development kit is used to implement the trained model and navigate the robot. The results show an average training accuracy of 82% with a training time of 30 minutes 15 seconds. As for the testing, the lowest accuracy is 90% for the T-junction with the computational time being 500 milliseconds for each frame. Therefore, the convolutional neural network is adequate to serve as classifier and navigate a maze solving robot.
Short-Term EV Charging Demand Forecast with Feedforward Artificial Neural Network
Authors: Effah Francis Boafo , Kwegyir Daniel , Opoku Daniel , Asigri Peter , Frimpong Emmanuel Asuming
Published: August 2023

The global increase in greenhouse gas emissions from automobiles has brought about the manufacture and usage of large quantities of electric vehicles (EVs). However, to ensure proper integration of EVs into the grid, there is a need to forecast the charging demand of EVs accurately. This paper presents a short-term electric vehicle charging demand forecast using a feedforward artificial neural network optimized with a modified local leader phase spider monkey optimization (MLLP-SMO) algorithm, a proposed variant of spider monkey optimization. A proportionate fitness selection is employed to improve the update process of the local leader phase of the spider monkey optimization. The proposed algorithm trains a feedforward neural network to forecast electric vehicle charging demand. The effectiveness of the proposed forecasting model was tested and validated with electric vehicle public charging data from the United Kingdom Power Networks Low Carbon London Project. The model's performance was compared to a feedforward neural network trained with particle swarm optimization, genetic algorithm, classical spider monkey optimization, and two conventional forecasting models, multi-linear regression and Monte Carlo simulation. The performance of the proposed forecasting model was assessed using the mean absolute percentage error of forecast and forecasting accuracy. The model produced a forecast accuracy and mean absolute percentage error of 99.88% and 3.384%, respectively. The results show that MLLP-SMO as a trainer predicted better than the other forecasting models and met industry standard forecast accuracy.
ANALISIS FRAMING TERHADAP PEMBERITAAN COVID-19 DI OKEZONE.COM DAN CNNINDONESIA.COM
Authors: Emeraldien Fikry Zahria , Hayati Kinanti R. , Nur Diny El Haanim , Adiputro Irvana Arum Sari , Lestari Afifah Dwi
Published: August 2023

This study examines Covid-19 coverage in two online mass media in Indonesia, okezone.com and cnnindonesia.com 11-13 and 20 April 2022 editions. In this research, researchers used Zhongdang Pan and Gerald Kosicki's framing analysis by applying descriptive qualitative research methods in the form of news text from the two online mass media. From the results of this study, researchers found that Okezone.com media news framing refers more to negative news angles where they inform about the facts and dangers of Covid-19 without warning or anything like that. Meanwhile, CNNIndonesia.com's news framing is more positive and contains an appeal. Media CNNIndonesia.com is also more inclined towards the government but still trying to be objective. The information that this media presents seems to urge the public to remain calm, even though there are still positive cases every day. In conclusion, the two online media Okezone.com and CNNIndonesia.com are able to report about Covid-19 in a frame that educates the public regarding what is currently happening objectively.

Keywords: Covid-19 news, Online Media, Framing Analysis, Pan and Kosicki.
LITERASI INFORMASI KESEHATAN PADA FENOMENA DIAGNOSIS MANDIRI COVID-19 MELALUI SUMBERDAYA ONLINE
Authors: Rohimakumullah Muhammad Al Assad , Primasari Intan , Wicaksono Angling Dwi , Fatona Anindya
Published: August 2023

This phenomenon of self diagnose through online resources in the era of the covid-19 pandemic is something that is dangerous in the diagnosis process. Information literacy about health plays an important role in the process of self-diagnosis of this phenomenon. This study will discuss how the experience of health information literacy is for patients who self-diagnose through online resources in the era of the covid-19 pandemic. This study will use a qualitative method by integrating a phenomenological approach and the seven pillars of information literacy standards. The results of this study show that there are physical and psychological vulnerabilities, which have an impact on information neglect, the quality of health information that makes patients depressed, and corrective actions from expert informants and references.

Keywords: health literacy information, online resources, phenomenology, self-diagnosis
STRATEGI PROGRAMMING INEWS DALAM MEMPERTAHANKAN PROGRAM SIARAN BERITA MENJELANG ASO 2022
Authors: Romaria Gustina , Astuti Sri Wahyuning
Published: August 2023

This research concentrates on the realm of television studies as an institution, to find out how the strategy of the iNews Siang news program is in maintaining news broadcast programs ahead of ASO 2022. The type of research used is descriptive qualitative research. The object of this research study is the iNEWS Afternoon program ahead of the Migration policy of Analog TV broadcasts to Digital TV broadcasts or Analog Switch Off (ASO). The problems in this study are dissected by analyzing how the strategy of the iNews Siang news program is in maintaining the news broadcast program ahead of ASO 2022, data collection techniques are applied to support information by conducting observations, interviews, and documents. The purpose of this research is to find out the strategy for the INEWS Siang news program in maintaining the news broadcast program ahead of ASO 2022, through the pre-production, production and postproduction stages observed as one unit in a series of program strategies. Participatory observation methods, interviews and literature on the news department, Morrisan's program strategy theory were built as a framework for the approach. The results obtained are iNews TV station programming strategy, especially in the iNews Afternoon Towards ASO 2022 program in broadcasting television broadcast programs to digital so that they can reach all audiences throughout Indonesia. Therefore, there are programs broadcast by the iNews Siang program in preparation for or ahead of ASO 2022. ASO stands for Analog Switch Off. The policy of discontinuing Analog TV broadcasts to be subsequently transferred to digital TV broadcasts is known as Analog Switch Off (ASO).

Keywords: ASO, iNEWSTV, digital broadcast, programming strategy, television journalist
Causes of dyspepsia in patients consulting Tikrit teaching hospital
Authors: Elias Kassim Samit , Saleh Mohamed Taha
Published: August 2023

To identify the causes of dyspepsia in Tikrit province, upper gastrointestinal (GIT) endoscopy was done and antral biopsies were taken from 200 patients. Abnormal findings on endoscopy were significantly higher in older age group ( 45 years and older ) than the younger age group ( below 45 years old ), 81 % versus 50%. Gastric ulcer, duodenal ulcer, gastritis and/or duodenitis and gastroesophageal reflux disease were found in 5%, 21 %, 22% and 2% of the younger age group and l 0%, 24%, 28% and 12% of the older age group respectively. Malignant diseases were found in 7 patients of the older age group but none in the younger age group. H.pylori was detected in 68% of younger and 81 % of older dyspeptic patients. Abdominal pain was the most frequent symptoms in patients included in this study. Loss of appetite, loss of weight and dysphagia were more common in those with malignancies.
The Subject of Madness in L. Binswanger's Existential Psychoanalysis
Authors: Tsvetkova Olga Alekseevna
Published: August 2023

The subject of the study is the madness in psychoanalysis. The author considers the problem of naturalistic and phenomenological understanding of the subject of madness in psychoanalysis of Z. Freud and in the existential psychoanalysis of L. Binswanger. The methodological basis is the psychoanalysis of Z. Freud, M. Heidegger's ontology and E. Husserl's phenomenology. L. Binswanger's critique of classical psychoanalysis is presented. The key differences of the definition of the subject in L. Binswanger's existential psychoanalysis are formulated. Naturalism is criticized for the lack of integrity in the consideration of man. Existential analysis is based on the idea that human existence is primary. To reduce a person's life to his drives and instincts means to deprive him of Humanity. L. Binswanger goes further than Z. Freud in his anthropology, arguing that man is more than a being thrown into the cycle of life and death, he can face his fate, the fate of humanity, he not only obeys the forces of life, but can also influence them by changing his fate. Mental health and illness are a reflection of this duality of being – acceptance of the given and individual choice. Madness is a rejection of transcendence, self–isolation in a self–created world-project, when both external and internal are only acting out its scenario, and the freedom of being is avoided, because it appears as a harbinger of non-existence.
The development of circus art in Russia until 2035 in a cultural aspect
Authors: Ganin Anatolii Andreevich , Bushkova Tatyana Vladimirovna
Published: August 2023

The role of the circus in the formation of the socio-cultural environment is determined. The aim of the work is to study the circus art in Russia in a cultural aspect. The subject of the study is the culturological aspect of the development of circus art until 2035; an analysis of two models of circus art: domestic and foreign is presented. The tasks and prospects in this area are outlined, the direction of further creative development of the Russian circus system until 2035 should be the creation of qualitatively new circus programs and performances using the capabilities of related arts (theatre, cinema, stage, etc.) and the use of modern technologies. The novelty of the study lies in the definition of the main trends in the development of circus art, the definition of global and domestic trends, a description of their features. The Russian circus industry is less segmented, unlike the Western one, which is distinguished by world-class high-tech shows, traditional circus troupes, circus performers with individual numbers. In Russia, the second segment is part of the circus system due to its demand among children and families. Recommendations are proposed for improving the circus business and its popularization: popularizing the circus as a form of family leisure, improving the human resources base, providing comprehensive support to the circus sector, etc.
Dossiê: A emoção no drama antigo: tragédia – Apresentação
Authors: Duarte Adriane Da Silva
Published: August 2023

O Dossiê "A emoção no drama antigo" reúne parte das contribuições apresentadas durante o VIII Colóquio do Grupo de Pesquisa Estudos sobre o teatro antigo: A emoção no drama antigo [Em memória da Profa Dra Zelia de Almeida Cardoso], que teve lugar na Faculdade de Filosofia, Letras e Ciências Humanas da Universidade de São Paulo, em setembro de 2022. A proposta do evento, como indica seu título, foi a de examinar como representou-se a emoção no teatro greco-latino e demais gêneros dramáticos. Foi também ocasião para homenagear a Professora Zelia de Almeida Cardoso, cofundadora do Grupo de Pesquisa e sua líder durante muitos anos, falecida em 2021, e, ao mesmo tempo, celebrar os vinte anos de sua criação.
Removal of a foreign body (pencil graphite) from the foveola
Authors:   Eye Microsurgery Ekaterinburg Center, Yekaterinburg, Russian Federation, Kleymenov A.Y. , Kazaykin V.N. ,   Eye Microsurgery Ekaterinburg Center, Yekaterinburg, Russian Federation, Lipina M.A. ,   Eye Microsurgery Ekaterinburg Center, Yekaterinburg, Russian Federation
Published: August 2023

Relevance. In the structure of ophthalmic morbidity, eye injury occupies one of the leading places due to a decrease or loss of vision, which entails an inevitable decrease in the patient's quality of life. According to modern literature, up to 41% of injuries to the organ of vision occur due to foreign bodies (intraocular foreign body – IOFB), which, in one case or another, remain in the eye, and in addition to obvious direct damage, can cause the development of an inflammatory reaction in long-term periods. Along with this, the fact of the invasion of the IOFB as a result of a primary injury does not always attract the attention of a patient or doctor, then the subsequent course of the process will depend on the material of which the foreign body is composed and its localization in the eye. Purpose. Using the example of a clinical case, to show the anatomical and functional results of surgical removal of a foreign body in the eye 14 years after a penetrating injury. Material and methods. This article presents a clinical case of an intraocular foreign body made of graphite, located on the surface of the fovea for 14 years without signs of an inflammatory reaction. The surgical technique for extracting graphite from the vitreal cavity and the long-term anatomical and functional results of the treatment are also described. Results. The patient underwent surgical treatment in the amount of vitrectomy with the removal of FB from the surface of the retina with a positive anatomical and functional result. As a result of a two-year follow-up period, the patient had no complications from surgical intervention and the stay of a foreign body in the eye with stable visual acuity. Key words: intraocular foreign body, graphite, vitreoretinal surgery, eye injury
Dirofilariasis in the vitreal cavity
Authors:   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation, Fayzrakhmanov R.R. ,   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation, Bogdanova V.A. ,   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation, Lebedko M.S. ,   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation, Bosov E.D. ,   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation,   N.I. Pirogov National Medical Surgical Center, Moscow, Russian Federation
Published: August 2023

Relevance. Dirofilariasis (Dirofilariasis, from Lat. «diro, filum» – «evil thread») is a disease that belongs to the group of transmissible zoonotic biohelminthiasis. Man is the facultative host of dirofilariae. That is why the survival rate of larvae in the human body is very low. Up to 50% of cases of dirofilariasis registered in humans are due to dirofilariasis of the visual organs. The intraocular form is extremely rare. The true incidence of dirofilariasis in humans is unknown, due to the fact that there is no official registration. Dirofilariae widely circulates in the natural environment, but at the moment there are no systematic measures to identify and deworming infected animals. In addition, due to insufficient awareness of doctors working in the practical healthcare system, this pathology is often detected and treated under various diagnoses of non-parasitic etiology. Purpose. To present a clinical case of a method of surgical removal of dirofilariasis in the vitreal cavity. Material and methods. The article presents a rare clinical case of intraocular invasion of dirafilariasis, and also describes the surgical tactics of helminth extraction. Results and discussion. The patient underwent surgical treatment in the volume of vitrectomy with the removal of the parasite with positive functional results. Surgical intervention is a radical and the only possible treatment in the case of intraocular invasion of dirofilaria. Conclusion. It is important to understand that localization of dirofilaria in the vitreous cavity, without radical surgical treatment, can lead to threatening consequences of vision loss. And the increase in the frequency of cases of dirofilariasis indicates the need for doctors to be wary of the differential diagnostic approach in identifying pathologies. Key words: dirofilaria, helminthiasis, vitreoretinal surgery, vitreous, intraocular invasion
HEART RATE VARIABILITY AS A MARKER OF MAXIMUM PHYSICAL LOAD IN PEOPLE WITH OBESITY
Authors: LISUN Y. , YEVSIEIEVA V.V. , POLYUKHOVICH L.M.
Published: August 2023

Introduction. Heart rate variability (HRV) and the autonomic nervous system are essential indicators of assessing the body's functional state. Physical activity and obesity, which are current problems of modern society, affect these indicators, but research on the relationship between them is limited.

Purpose: to determine the maximum level of physical activity in obese people in the preoperative period.

Materials and methods. A group of obese individuals who were scheduled for weight loss surgery were involved. The participants performed special tests and physical exercises that allowed them to determine their maximum level of physical exertion. Using a step test, which included walk-up stairs to complete exhaustion, indicators of heart rate variability, heart rate, and recovery time after exercise were recorded.

Results. Based on the analysis of the obtained data, it was established that overweight patients can tolerate a high level of physical exertion without significant changes in heart rate variability and blood pressure. At the same time, in obese patients, there is a decrease in exercise tolerance and heart rate variability, which requires introducing a safe level of physical activity into preoperative preparation with monitoring of the patient's general well-being.

Conclusion. Obese people are characterized by a low level of physical activity, which complicates preoperative preparation and prolongs its duration
Investigation of Personal and Social Sports Identities of Elite National Karate Players via Self Identity Chart
Authors: SANBERK İsmail , TÜRKERİ Cenab , PARSAK Burhan
Published: August 2023

The aim of this study is to investigate ideal and non-ideal image of six Turkish national players and their cognitive representation of karate players. This study was carried out with six young adult elite karate athletes who were successful in national and international tournaments attending the Department of Physical Education and Sports. The data of this study were collected via repertory grid, a semi-structured interview technique. Self-identity graph of each participant was obtained and analyzed based on repertory grid data. The findings show that all the participants’ personal and social sport identities, except one participant, are positive. İn the study, it was found that the participants with high self-esteem defined themselves as karate players with positive personal constructs of ideal self and social self. As a result, this study shows that the self-identity graph will provide functional information in revealing -athletes’- sports-related self esteem, personel and social sports identities. This study has carried out about young adult elit karete players in Turkey suceessed at national and international tournament. With Studies which will do in the future, it may be revealed ameteur, young and junior karete players’ personal and social sport identity via self identity graph.
Afectarea hepatică în mucoviscidoză
Authors: Stana Bogdan A. , Bozomitu Laura , Grigoraş Sabina , Popovici Paula
Published: August 2023

Among the systemic impairment in cystic fibrosis there is also hepatobiliary tract involvement, with some genetic determinants of the disease manifesting as cystic fibrosis-associated liver disease (CFLD). The pathogenesis, natural history and cyrrhogenic evolution of CFLD are discussed in relation to the multiple phenotypes of cystic fibrosis. The CFLD therapy is nonspecific, the disease progression to cirrhosis is unpredictable, and the CFTR modulators offer a still underinvestigated therapeutic alternative.
Sănătatea mintală şi stima de sine corelate cu performanţele academice ale tinerilor din învăţământul din Sri Lanka
Authors: Firose M. , Musthafa M.M. , Marikar F.M.M.T.
Published: August 2023

Objectives. This research investigation was done to study the relationship between mental health and self-esteem with academic achievement among Sri Lankan youths. 
Method. The sample for this study was selected using purposive sampling from educational institutions of Ampara District, Sri Lanka. The total number of samples was 516.  The age range of the participants in this study was from 16 to 24 years old (mean age: 19.2 years old). Standard tools were used for data processing, such as the Mental Health Scale developed by Kamlesh Sharma and the Rosenberg’s Self-Esteem Scale. Further, academic achievement was measured using secondary data, such as semester marks list of youth from schools, colleges and universities. The personnel information plan created by the researcher was used to collect information along with relevant demographic and social data. The pretested questionnaire was reliable, being validated before the final data collection. The data analysis method was developed in this study. The informants were contacted individually by the investigator, and the data were obtained through questionnaires. Data retention is limited to a period of three months. 
Results. A statistical analysis, using the t-test, ANOVA, correlations and regressions, was performed. The result revealed that, out of eight demographic variables in this study, five variables (i.e., age, locality, father’s education, parent’s income and type of family) were in a significant correlation with mental health of youths and, also, only two variables (i.e., locality and type of family) were in significant correlation with the self-esteem of the youths. Further results revealed that, out of eight demographic variables in this study, seven variables (i.e., age, gender, locality, father’s education, mother’s education, parent’s income and type of family) had a significant correlation with the academic achievement of youths. 
Conclusions. The results indicated that there is a significant positive relationship between mental health and self-esteem with the academic achievements of youths.
Integrating Multiscale and Machine Learning Approaches towards the SAMPL9 LogP Challenge
Authors: Draper Michael , Waterman Asa , Dannatt Jonathan , Patel Prajay
Published: August 2023

Three techniques intertwining and integrating quantum mechanics (QM), molecular mechanics (MM), and unsupervised machine learning were utilized in the prediction of the toluene-water partition coefficient (logP tol/w) for sixteen drug molecules as part of the ninth iteration of the Statistical Assessment of the Modeling of Proteins and Ligands (SAMPL) series of blind prediction challenges. The three blind submissions yielded mean unsigned errors (MUE) ranging from 1.53-2.93 logPtol/w units. Out of all submissions (ranked and unranked), one of these methods yielded the third lowest MUE of 1.53 indicating an overall increase in errors with respect to predicting octanol-water partition coefficients (logPo/w¬) for similar drug-like molecules. After applying numerous QM and MM approaches into multiscale and data-driven approaches to supplement the initial analysis, MUEs were reduced to 1.00 logPtol/w units when using density functional theory (DFT) on a single conformation, while generating an ensemble of rotamer structures elucidates subtle electronic and structural effects that are not considered in the analysis of a single conformation. Computational approaches developed for these SAMPL challenges will continue to serve as standard predictive tools for rational drug design.
Unveiling an unexpected superoxide-mediated photooxidation mechanism of squalene monohydroperoxides to squalene hydroperoxy cyclic peroxides through ESR and LC-MS/MS analyses
Authors: Khalifa Saoussane , Enomoto Masaru , Nakagawa Kiyotaka
Published: August 2023

Lipid cyclic peroxides are a rarely reported and documented class of compounds in the human organism. Recently, we reported the formation of squalene (SQ) hydroperoxy cyclic peroxides derived from SQ monohydroperoxide isomers (SQ-OOHs) for the first time. Notably, we successfully detected and quantified cis-2-OOH-3-(1,2-dioxane)-SQ in the human skin. Nevertheless, the underlying mechanism governing the formation of these compounds remained elusive. Therefore, in the current study, we set to determine the reaction’s mechanism. To this end, a comprehensive analysis of the precise conditions involved in the onset and propagation of this conversion was carried out by oxidizing total SQ-OOHs under different conditions, including singlet oxygen (1O2), thermal, and photoinduced oxidations monitored by quantifying the generated 2-OOH-3-(1,2-dioxane)-SQ using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Radical intermediates were thoroughly investigated using Electron Spin Resonance (ESR) with the aid of spin traps and radical references. Moreover, calculations of SQ-OOHs’ electrostatic charges were performed on Spartan 18 software. We found that the reaction is ideally induced and favored under photooxidation in the presence of 3O2 in hexane, and that superoxide radical (O2•−) is the first key intermediate in this mechanism, whereas peroxyl radicals were the major species observed throughout the oxidation. Chemical calculations provided an explanation for the targeting of tertiary SQ-OOHs by this reaction and gave further evidence on the proposed heterolytic cleavage initiating the reaction. The novel oxidation mechanism suggested herein offers new insights into understanding lipid secondary oxidation and is a promising finding for further studying lipid cyclic peroxides in general.
Data-Driven Exploration of Silver Nanoplate Formation in Multidimensional Chemical Design Spaces
Authors: Chiang Huat Thart , Vaddi Kiran , Pozzo Lilo D.
Published: August 2023

We present an autonomous data-driven framework that iteratively explores the experimental design space of silver nanoparticle synthesis to obtain control over the formation of a desired morphology and size. The objective of the method is to autonomously identify design rules such as the effects of the design variables on the structure of the nanoparticle. The framework balances multimodal characterization methods (i.e. UV-Vis spectroscopy, SAXS, TEM), taking into account the cost of performing a measurement and the quality of information gained. By integrating with an AI agent, we identify important design variables in the synthesis of plate-like silver particles and outline how each variable affects plate thickness, radius, and polydispersity. Our findings are consistent with the literature, demonstrating that the automation framework could be further applied to new systems that have not been well characterized and understood. The framework is generalizable and allows tangible knowledge extraction from the high-throughput experimental runs while still taking inherent stochasticity into consideration.
Predicting Surface Tensions and Electrical Conductivities for High Molecular Weight Ionic Liquid Propellants Using Quantitative Structure-Property Relationships (QSPR)
Authors: Wolf Mark J. , Chambreau Steven D. , Sengupta Debasis , Newsome David A. , Vaghjiani Ghanshyam L.
Published: August 2023

Quantitative Structure-Property Relationships (QSPR) take in existing experimental property data and output predicted properties using statistical analysis and linear regressions. A priori, QSPR can provide practical results for ionic liquid (IL) propellants of any physical property, such as density, viscosity, surface tension, electrical conductivity, etc., as well as of any chemical property such as ignition delay time. It saves time and costly resources used when first synthesizing the IL and measuring its various properties to see if it meets mission requirements. QSPR also provides benefits over first principles theoretical computational methods such as increased accuracy and reduced computational time, therefore reducing the cost over current approaches in molecular dynamics simulations. In this work, QSPR was used to predict surface tensions and electrical conductivities of ionic liquids with high molecular weights. These high molecular weight ionic liquids are being investigated for applications in electrospray propulsion because of their omniphobicity and high short-term thermal stability characteristics, which potentially give them a performance advantage over existing propellants.
LC-ESI-HRMS - lipidomics of phospholipids – Characterization of extraction, separation and detection parameters
Authors: Rund Katharina , Carpanedo Laura , Lauterbach Robin , Wermund Tim , West Annette , Wende Luca , Calder Philipp , Schebb Nils Helge
Published: August 2023

Lipids are a diverse class of molecules involved in all biological functions including cell signaling or cell membrane assembly. Owing to this relevance, LC-MS/MS based lipidomics emerged as a major field in modern analytical chemistry. Here, we thoroughly characterized the influence of MS and LC settings – of a Q Exactive HF operated in Full MS/data-dependent MS2 TOP N acquisition mode - in order to optimize the semi-quantification of polar lipids. Optimization of MS-source settings improved signal intensity by factor 3 compared to default settings. Polar lipids were separated on an Acquity Premier CSH C18 reversed-phase column (100 x 2.1 mm, 1.7 µm, 130 Å) during an elution window of 28 min, leading to sufficient number of both data points per peaks as well as MS2 spectra. Analysis was carried out in positive and negative ionization mode enabling detection of a broader spectrum of lipids and to support the characterization of lipids. Optimal sample preparation of biological samples was achieved by liquid-liquid extraction using MeOH/MTBE resulting in an excellent extraction efficiency of >85% with an intra-day and inter-day variability of <15%. The optimized method was applied on the investigation of changes in the phospholipid pattern in plasma from human subjects supplemented with n3-PUFA (20:5 and 22:6). The strongest increase was observed for lipids bearing 20:5 while 22:4 bearing lipids were lowered. Specifically, LPC 20:5_0:0 and PC 16:0_20:5 were found to be strongest elevated while PE 18:0_22:4 and PC 18:2_18:2 were decreased by n3-PUFA supplementation. These results were confirmed by targeted LC-MS/MS using commercially available phospholipids as standards.
Electrochemical capture and conversion of CO2 into syngas
Authors: Kim Yongwook , Lees Eric W. , Donde Chaitanya , Waizenegger Christopher E.B. , Simpson Grace L. , Valji Akshi , Berlinguette Curtis P.
Published: August 2023

For waste CO2 to be electrolytically converted into higher-value chemicals and fuels, electrolyzers that drive the CO2 reduction reaction need to be integrated with upstream CO2 capture units. However, this has not yet been demonstrated because of the large operational gap for the capture and conversion steps. Here, we report a coupled carbon reactor that captures and converts CO2 into syngas with a 1.7:1 ratio of H2 to CO. The resulting syngas can be utilized in the production of a wide range of valuable chemicals. This CCR uses a packed bed absorption column (“capture unit”) to react alkaline aqueous solution enriched in K2CO3(aq) with CO2 to form bicarbonate enriched solutions (“reactive carbon solutions”). These reactive carbon solutions are then fed into an electrochemical reactor (“bicarbonate electrolyzer”) to form CO(g) and OH– product. This alkaline product is then passed through a gas-liquid separator (“separator”) and recycled back to the capture unit for further reaction with CO2(g). These collective elements close the full loop for CO2 capture and conversion. An electrochemically inert CO2 capture promoter (glycine) was used to better match the CO2 capture rates in the absorption column to the OH– production rates in the electrolyzer, thereby producing CO at steady-state without intervention. We demonstrate that the CCR captures and converts CO2 from simulated flue gas (20% CO2; 80% N2) into CO with a Faradaic efficiency of 30% at 100 mA cm–2 for 30 hours of operation.
Tough Hydrogels for Load-Bearing Applications
Authors: Petelinsek Nika , Mommer Stefan
Published: August 2023

Tough hydrogels have emerged as a promising class of materials to target load-bearing applications, where the material has to resist multiple cycles of extreme mechanical impact. A variety of chemical interactions and network architectures have been used to enhance the mechanical properties and fracture mechanics of hydrogels. In recent years, the mechanical properties of high-performance hydrogels are benchmarked, however this is often incomplete as important variables like water content are largely ignored. In this review, we aim to clarify the reported mechanical properties of state-of-the-art tough hydrogels by providing a comprehensive library of fracture and mechanical property data. First, we briefly discuss modes of energy dissipation at work in tough hydrogels, which we use to categorize the individual data sets. Next, we introduce common methods for mechanical characterization of high-performance hydrogels, followed by a detailed analysis of the current materials and their (fracture) mechanical properties. Finally, we consider several current applications, compare high-performance hydrogels with natural materials, and discuss promising future opportunities of tough hydrogels.
Lifting Hofmeister’s curse: Impact of cations on diffusion, hydrogen bonding and clustering of water
Authors: González-Jiménez Mario , Liao Zhiyu , Williams Elen , Wynne Klaas
Published: August 2023

Water plays a role in the stability, reactivity, and dynamics of the solutes it contains. The presence of ions alters this capacity by changing the dynamics and structure of water. However, our understanding of how and to what extent this occurs is still incomplete. Here a study of the low-frequency Raman spectra of aqueous solutions of various cations using optical Kerr-effect spectroscopy is presented. This technique allows for the measurement of the changes that ions cause in both the diffusive dynamics and the vibrations of the hydrogen-bond structure of water. It is found that when salts are added, some of the water molecules become part of the ion solvation layers, while the rest retain the same dif-fusional properties as those of pure water. The slowing down of the dynamics of the water molecules in the solvation shell of each ion was found to depend on its charge density at infinite dilution conditions and on its position in the Hofmeister series at higher concentrations. It is also observed that all cations weaken the hydrogen bond structure of the solution and that this weakening depends only on the size of the cation. Finally, evidence is found that ions tend to form amorphous aggregates even at very dilute concentrations. This work provides a novel approach to water dynamics that can be used to better study the mechanisms of solute nucleation and crystallization, the structural stability of bio-molecules, and the dynamic properties of complex solutions such as water-in-salt electrolytes.
Enolate addition to bicyclobutanes enables expedient access to 2-oxo-bicyclohexane scaffolds
Authors: Woelk Kyla , Dhake Kushal , Schley Nathan , Leitch David
Published: August 2023

We report the synthesis of 2-oxo-bicyclo[2.1.1]hexanes (2-oxo-BCHs) from bicyclobutanes (BCBs) and readily available enolate precursors. We propose this reaction proceeds via initial enolate addition to the bicyclobutane, followed by an intramolecular acyl substitution by the resulting enolate intermediate. Glycine-derived enolates directly give protected 2-oxo-3-amino-BCH derivatives that can be further functionalized. Arylacetate derivatives are also suitable enolate precursors, giving 2-oxo-3-aryl-BCH scaffolds from readily available starting materials.
Revisiting Ion-Pair Interactions in Phase Transfer Catalysis: From Pure Ionic Compounds to Real Catalyst Systems
Authors: Iribarren Iñigo , Mates Eric , Trujillo Cristina
Published: August 2023

Ion-pairing is a fundamental phenomenon that significantly influences phase-transfer catalysis. In this study, we conduct a comprehensive investigation of ion-pair interactions, aiming to establish a comprehensive understanding of their nature and implications. The study begins with the examination of pure ionic compounds to define the concept of an ion-pair in the context of phase-transfer catalysis. Subsequently, a diverse range of ion-pair catalyst models were explored to gain insight into the factors governing their interactions. Finally, the focus shifts towards the characterization of real phase- transfer catalysts, bridging the gap between theoretical models and practical applications. Through a combination of computational approaches and theoretical analysis, this work provides valuable insight into the nature of ion-pair interactions within phase-transfer catalysis fields.