bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovations in Dairy Cattle Management: Enhancing Productivity and Environmental Sustainability
Authors: Gheorghe-Irimia Raluca Aniela , Sonea Cosmin , Tapaloaga Dana , Gurau Maria Rodica , Ilie Lucian-Ionel , Tapaloaga Paul-Rodian
Published: November 2023

The dairy industry stands at the intersection of two critical global challenges: the need to meet rising demands for high-quality dairy products and the imperative to reduce its environmental impact. This study’s primary aim is to bridge the historical-to-modern gap in dairy cattle management practices and to provide a comprehensive perspective that encompasses the industry’s historical evolution and contemporary realities. It engages in a meticulous examination of the multifaceted dimensions of dairy cattle management, commencing with an exploration of historical methodologies and advancing into the realms of modern breeding and genetics, nutritional advancements, innovations in housing and welfare, environmental sustainability, and the integration of precision farming technologies. Throughout this research, there is an unwavering emphasis on the compelling necessity for sustainable and innovative approaches to confront prevailing challenges, particularly in domains such as animal health, welfare, and the reduction of the industry’s environmental footprint. The findings of this study shed light on the critical importance of adopting sustainable and inventive methodologies in the realm of dairy cattle management. It not only encourages cattle managers but deems it crucial for them to fuse historical practices with contemporary technologies, with a special focus on enhancing breeding strategies, refining precision farming techniques, and upholding principles of ecological responsibility. Paramount in these considerations are the promotion of animal welfare, the minimization of environmental impact, and the pursuit of heightened productivity, all of which are indispensable for the industry’s long-term sustainability. From a pragmatic standpoint, this research offers actionable recommendations for dairy farmers. For example, the implementation of sustainable practices holds the promise of not only enhancing economic viability but also of bringing the operations of dairy farms in alignment with societal expectations. These practices have the dual potential to amplify profitability while mitigating environmental repercussions, thereby fostering societal acceptance. While the study duly acknowledges the inherent limitations associated with the complex and multifaceted nature of the dairy industry, it confidently lays the foundation for prospective research endeavours. In conclusion, this research serves as a pivotal starting point for the advancement of dairy cattle management in terms of sustainability, economic viability, and societal alignment.
The Mountain Products Market - Post Covid-19 Period
Authors: Antohe Radu Gheorghe , Catuna Carmen Boca , Constantinescu Claudia Emanuela
Published: November 2023

The future of Romania’s mountain areas is based on living mountains on which sustainable and integrated development and a good quality of life are promoted and which can sustain the national mountain economy over time. Mountain products can be approached as a healthy solution to help a nation’s economic development leading to higher living standards. The main challenges related to mountain products and the effects of their development are presented, taking into account the quality of all products obtained on the mountain. This study analyzes the effects of the Covid-19 crisis on the producer market in the mountain areas in Romania, trying to provide solutions and development proposals. Analyzing the post Covid-19 trends of the mountain products market and taking into account the unique and natural specificities and properties, we will propose some solutions that could be considered for the development of this market. Only strategic planning can lead to a sustainable development of the mountain products market in Romania.
On Doubled and Quadrupled Fibonacci Type Sequences
Authors: Yilmaz Nur Şeyma , Włoch Andrzej , Özkan Engin , Strzałka Dominik
Published: November 2023

In this paper we study a family of doubled and quadrupled Fibonacci type sequences obtained by distance generalization of Fibonacci sequence. In particular we obtain doubled Fibonacci sequence, doubled and quadrupled Padovan sequence and quadrupled Narayana’s sequence. We give a binomial direct formula for these sequences using graph methods, and also we derive a number of identities. Moreover, we study matrix generators of these sequences and determine connections with the Pascal’s triangle.
Impact of Public Transportation on European Countries’ Development: a Spatial Perspective
Authors: Matyas Andreea
Published: November 2023

Sustainability is a key topic nowadays, mostly because in the last decade the pollution levels have reached an all-time high. National governments are searching for sustainable and environmentally friendly solutions to decrease the amount of pollution. This study is a cross-sectional study on 27 European countries, using data gathered in 2020. This study's main goal is to show the environmental sustainability of public transportation and its impact on country development in Europe. The methodology used in this study will consist of spatial econometrics methods with visual maps and graphs to help with a better visual representation of the phenomena presented. The empirical evidence will be confirmed by the spatial regression's results. Because the spatial diagnostic tests revealed that the spatial processes are present in terms of both spatial lag and spatial errors, the model that was used was a Spatial Autoregressive Moving Average Model (SARMA). Moreover, the environmental sustainability of public transport is also a significant factor. The expected results from which this study began – specifically, that the spatiality has a significant impact in modelling the relationship between public transportation and economic development – were confirmed.
Development of Chronology for Historical Mining Shaft Remains in the Vicinity of Tarnowskie Góry Based on Radiocarbon, Luminescence and Dendrochronological Dating
Authors: Pawełczyk Fatima , Bolik Agnieszka , Błachut Bartłomiej , Kamińska Anna , Opała-Owczarek Magdalena , Malik Ireneusz , Wojcik Michał , Zakrzewska Zofia , Pawlak Zbigniew , Poręba Grzegorz
Published: November 2023

This study focused on determining the age of sediments found in the remains of historical mining in the post-exploitation field in Tarnowskie Góry, Poland. The limited historical sources indicated that lead ore and silver were mined there from the 12th to 20th centuries. The research utilised radiocarbon dating, optically stimulated luminescence (OSL) and fallout radioisotopes analysis to establish a chronology of the mining remains. Excavations were conducted on three historical mining shafts. In one of them, remains of old construction wood were found. Radiocarbon dating yielded 12 results, with the majority falling within the range of 1435 cal AD to 1645 cal AD. Two results were significantly older and covered the period of the beginnings of the Polish State. OSL dating provided results ranging from 2.5 ka BP to 216 ka BP, a time range much older than that indicated by radiocarbon dates. The OSL ages were found to be greatly overestimated, indicating that the luminescence signal was not reset during the redeposition of sediments. While the obtained results provided a preliminary chronology of the study site, further detailed research, especially regarding the older samples, is necessary to enhance our understanding of the mining history in the area.
Leadership in Public Health: Challenges and Opportunities In Improving the Quality of Public Services
Authors: Da Silva Ana Claudia Rodrigues , Barilli Elomar Christina Vieira Castilho , Costa Dayane Dayse de Melo , Rodrigues Glaydson Campelo de Almeida , Martins Tayane Moura , Da Costa Matheus Gomes , De Souza Thamirys Sartori , Lira Rivânia da Silva , Dos Santos Leandra Caline
Published: November 2023

Purpose: This work examines the role of Leadership in the Public Sector, with a focus on the leaders' interaction with their teams, aiming to build a harmonious interpersonal relationship to ensure successful management. This, in turn, allows for the creation of management with a predominantly democratic character, with the potential to address both local and societal needs. In this context, it is emphasized that motivation is something intrinsic to each individual, and the leader must have the potential to stimulate it. The general objective of this work is to analyse the importance of leadership in improving the performance of employees in the context of Public Health.
 
Theoretical Framework: Leadership permeates all managerial activities and is not an isolated activity. Its importance is underestimated when judged solely in terms of the proportion of managerial activities that are strictly related to team management.
 
Method/design/approach: This research is exploratory in nature, as it conducted a literature review on the role of leadership in public institutions, using various publicly available sources such as books, journals, theses, internet articles, and monographs.
 
Results and conclusion: The coordinator and 10 employees from various positions out of the total of 40 were selected to participate in the research. It is noteworthy that the leader holds a degree in Pedagogy and is currently pursuing Nursing, is 34 years old, female, and has previously served as a coordinator in the same UBS for 4 years in the recent past, marking her first leadership experience at the age of 26. Currently, she leads a team of 40 people.
 
Research implications: The research emphasizes the creation of a management with a democratic predominance. If the results indicate that leadership plays a significant role in this aspect, it may influence management practices in healthcare units and potentially in other public sector organizations.
 
Originality/value: The research focuses on the field of Public Health, which can be considered original, as it is a specific and critical area of the public sector that is not frequently addressed in general leadership studies.
Instant Determination of Moisture and Bulk Density of Woodchips in Cellulose Industry
Authors: Kumov Elisa Pizzaia Goltz , Cremonez Victor Gonçalves
Published: November 2023

Purpose: This research aims to achieve the instantaneous determination of moisture content and bulk density of wood chips for energy generation and pulp production in the pulp and paper industry.
 
Theoretical framework: The moisture content and bulk density of woodchips influence the quality of biomass for energy generation and cellulose production in various ways. These variables affect the calorific value, mass and volume of logistical transport, the quantity of reagents in the reactor for wood delignification, among other factors. For this reason, a quick and accurate evaluation of these factors in the field is of fundamental importance to improve industrial quality and productivity.
 
Method: To achieve this goal, a pilot test was conducted using a capacitive sensor and a portable scale to determine the moisture and bulk density of wood chips. Calibration equations were developed in the laboratory for the sensor, correlating the readings with the actual moisture content of seven types of wood chips, including Eucalyptus spp. and Pinus spp. The results of field measurements using these equations were compared with the gravimetric method, as well as bulk density measurements.
 
Results and conclusion: The moisture calibration equations showed a high correlation between the capacitive sensor and the gravimetric method. The field density results were similar to those obtained in the laboratory. It was concluded that the investigated methods show promise for use in the pulp and paper industry.
 
Research implications: The validation and accuracy of portable instruments for the instantaneous determination of moisture content and bulk density of wood chips are of utmost importance for manufacturers of portable meters and for industries that use this raw material.
 
Originality/value: The instantaneous determination of moisture content and bulk density can contribute to improving the energy and production efficiency of boilers that generate heat for pulp digesters. Moreover, it optimizes logistical transportation and quality control against the attack of xylophagous organisms, preventing waste of raw materials, which is essential for sustainable development.
Assessment of color stability of shade less composite resin: an in-vitro study
Authors: Nour Omnia , Alburaidi Wedad
Published: November 2023

Objective:
This study aimed to assess the color stability of omnichroma composite resin after immersion in coffee, cola and iced tea.
Methods:
A total of 30-disc shape specimens of omnichroma, 10mm diameter and 2mm thickness, were made in a Teflon mold. The samples were washed and stored in artificial saliva for 24 hours in a 37°C incubator. The top surfaces of specimens were polished with polishing disks (Sof-lex; 3M ESPE). Samples were divided randomly into 3 groups, and each group contained 10 discs. Groups were immersed in 15 ml of 3 different storage media (cola, iced tea and black coffee). Immersion groups were stored in an incubator at 37 °C. Color assessment was carried out by VITA Easy shade 2.0 spectrophotometer color assessment device according to the CIE L*a*b*system, against a gray background to measure baseline records for the samples. After 4 weeks, a second record was taken for the samples after they were gently rinsed with distilled water and dried. The experimental data were statistically evaluated using the Wilcoxon sign rank test with a significance level < 0.05%.
Results:
The highest color change was reported with coffee (ΔE=20.16) followed by cola (ΔE=19.6) and iced tea (ΔE=4.75).
Conclusion:
All assessed drinks resulted in discoloration of the shade less composite resin material above the clinically acceptable level (ΔE>3.3) after 30 days of immersion. Coffee has the highest staining among the three drinks, followed by cola, and then iced tea.
Nasoalveolar Molding for Unilateral Cleft Lip and Palate with 4 Years Follow Up: A Case Report
Authors: Alqadi Soha , Qazali Ahmed , Almuzaini Sarah , Dawood Fatma , Melebari Jalal
Published: November 2023

Background: Primary surgical repair of the lip and nose usually results in wide scar and reduced nasal esthetic. Presurgical nasoalveolar molding (NAM) aim to reduce the severity of the initial cleft deformity, thereby enabling the surgeon to perform better outcomes. The aim of this case report is to document the long-term (4-year) outcome of NAM and surgical repair of the unilateral cleft lip and palate.

Case presentation: Two days old female neonate with unilateral cleft lip and palate was presented with initial intersegment distance of 8mm. Molding plate was inserted and modified weekly to guide the alveolar cleft segments to the desired position. The nasal stent was attached to the appliance on the 16th day after reducing the cleft gap to 5mm and it was adjusted weekly to mold the nasoalveolar complex into the desired shape. At 3 months of age, the intersegment distance was 3mm and the patient underwent primary surgical repair of the lip and nose. At age of 9 months, a palatal repair was performed.

Result: At the last patient's follow up visit (at age of 4 years), there were minimal scars on the lips and nose, and all primary teeth had erupted except the upper left lateral incisor.

Conclusion: Nasoalveolar molding is effective in reducing the width of the cleft and improving the nasal architecture.
PERANCANGAN GAME PLATFORMER “GRAPPLE” PADA PC
Authors: Trenaldy Gery , Haris Darius Andana , Pragantha Jeanny , Lim Carlene
Published: November 2023

"Grapple" is a platformer game designed using Unity and targeted to be played on PC. Sprites and assets used in this game were created with Pixilart. Players can choose between 2 level packs where each level pack consists of 6 levels. The goal in the game "Grapple" is to pass all available obstacles with the help of a grappling gun and get the highest score possible from each played level. Design & Planning carried out using game design methods. Testing is carried out using black box testing.
OPTIMASI PARAMETER MESIN 3D-PRINTER MARKFORGED MARK TWO MATERIAL ONYX-CARBON FIBER REINFORCED DI PT. MATAHARI MEGAH
Authors: Hendito Mikael Sean , Halim Agus , Raynaldo Kevin
Published: November 2023

Revolusi industri 4.0 memiliki konsep yang berpusat pada otomatisasi, yang dibantu oleh teknologi informasi dalam penerapannya. Additive manufacturing merupakan salah satu pilar dalam mengembangkan suatu industri, additive manufacturing terdiri dari rapid prototyping, direct digital manufacturing, dan 3D-printing. Salah satu filamen 3D-printing yang menjadi standar industri adalah Onyx karena kekuatannya yang melebihi filamen lainnya. Pengaplikasian filamen Onyx pada industri dibuat untuk jaw gripper, bracket, soft jaw, ulir, dan jigs. Salah satu produk dari PT. Matahari Megah menggunakan filamen ini untuk jaw gripper, namun penggunaan material ini masih belum optimal, karena masih belum ada karakterisasi dari material Onyx yang diperkuat serat karbon. Metode penelitian ini menggunakan studi kasus sebagai studi awal penelitian lanjutan, studi ini difokuskan untuk mengevaluasi pengaruh variabel bebas ke variabel terikat yang akan diterapkan oleh PT. Matahari Megah. Studi ini mempertimbangkan parameter infill pattern dan infill density. Dari penelusuran studi pendahuluan didapatkan konfigurasi parameter untuk mendapatkan kuat tarik yang optimal yaitu pada data I dengan parameter 2 infill pattern memiliki 2 level dan infill density memiliki 3 level menggunakan infill pattern Triangular dengan kerapatan 49%, data II dengan parameter 2 faktor dan 2 level menggunakan infill pattern Rectangular dengan kerapatan 70%, dan data III dengan parameter 3 faktor dan 3 level menggunakan infill pattern Rectangular dengan kerapatan 80%.
Daftar Isi JSSTK V1N1
Authors: JSSTK
Published: November 2023

Daftar Isi
PELECEHAN SEKSUAL DI LINGKUNGAN MAHASISWA
Authors: Hidayat Muhammad Syarif , Nugraha Aditia , Wiguna Muhammad Nasrullah , Supriyono Supriyono
Published: November 2023

Perempuan umumnya kerap mengalami jenis pelecehan seksual terutama pelecehan dalam bentuk verbal. Umumnya laki-laki berpikir tindakannya tidak dianggap melemahkan pihak perempuan dan merupakan tindakan dari pelecehan seksual. Tujuan pada penelitian ini yaitu untuk menganalisis kecenderungan pelecehan di kalangan mahasiswa dan seberapa besar dampaknya bagi psikologis mahasiswa yang mengalami tindakan pelecehan tersebut. Metode pada penelitian yakni metode studi pustaka, yaitu menggunakan literatur terdahulu terkait dengan topik penelitian. Pada penelitian ini menggunakan studi pustaka yang berasal dari jurnal atau karya ilmiah terpublikasi yang memiliki topik serupa dengan penelitian. Studi literatur yang digunakan untuk menjelaskan fenomena terkait dengan isu sosial terkait dengan pelecehan di kalangan mahasiswa. Hasil penelitian menunjukkan bahwa pelecehan seksual di lingkungan mahasiswa masih tergolong tinggi karen kurangnya perhatian dari sekitar dan kurangnya Pendidikan tentang seksual. Hal ini disebabkan karena pada lingkungan kampus lebih menekankan pada Pendidikan yang sesuai dengan minat mahasiswa, sehingga banyak mahasiswa yang tidak mengetahui tentang pelecehan seksual yang umumnya berbentuk pelecehan verbal.
The making of a digital archive, by a non-archivist
Authors: Medina de Loera Wendy Alejandra
Published: November 2023

This online exhibit has been created to share relevant insights about the process of preparing a digital archive for junior and senior scholars who have no training as archivist. The exhibit is based on my experience as a non-archivist making David Wurfel digital archive. The reflections and ideas captured in this online exhibit were triggered and enriched by multiple readings and the project team. The hope is that the ideas discussed in this exhibit will be helpful to all of those who may not have training as archivists but may be interested in preserving and sharing material via its digitization and display through an online archive.
Features and types of self-presentations in educational video blogging
Authors: Filipova Alexandra Gennadyevna , Skrypnikova Ekaterina Mikhailovna , Abrosimova Evgeniya Evgen'evna
Published: November 2023

The rapidly developing video blogosphere attracts a diverse audience, including children and young people. The latter consume both entertaining and educational content. The Covid-19 pandemic has contributed to the increased digitalization of education, as well as the development of educational video blogging. The purpose of our study is to analyze the self-presentations of educational video bloggers and their typology. Empirical research materials are represented by texts of expert interviews with teacher-bloggers (N = 10) and focus groups with schoolchildren (N = 69), as well as direct videos posted on the channels of 48 educational bloggers (240 in total). Analysis of the video, accompanied by the study of scientific literature and expert statements, made it possible to identify two main and four additional types of self-presentation of educational video bloggers – «expert», «practitioner», “entrepreneur”, “creative type”, “insider”, “experimenter”. Among the criteria for identifying these types: emotional techniques; use of teaching tools and techniques, including technical ones; linguistic means; expression of one's own position; dialogical; background design, choice of clothing, etc. The description of each type of self-presentation is accompanied by examples from selected cases of English-speaking and Russian-speaking educational bloggers. Typology can be used both for self-reflection by the authors of educational channels and for research in this area. Subsequently, the typology will be verified using the factor analysis method on the described sample of 240 educational videos.
Criteria and factors of digital activism effectiveness: expert assessments
Authors: Abramova Sofya Borisovna
Published: November 2023

This article examines the problem of the effectiveness of digital participation, and sets the goal of defining criteria for measuring it and identifying factors that act as barriers to the implementation and achievement of full results of digital civic initiatives. The diversity of understanding efficiency is revealed in the context of the specifics of social processes and digital communications. It is shown that in the Russian and foreign scientific sociological field has not been formed a wide and substantiated experience and methodology for studying the effectiveness of online forms of civic activism, which determines the relevance of the research topic, as well as the need for a methodological solution to the problem. The empirical basis of the study is a survey of 16 experts in the field of digital activism from 8 federal districts of the Russian Federation conducted. The novelty of the work is related to the typology of the criteria for the effectiveness of digital participation, based on the analysis of expert assessments: effectiveness as effectiveness, effectiveness as the level of activity and involvement of citizens, effectiveness as development (creativity and innovation), social effectiveness and social effects, effectiveness as dialogue and the development of social partnership. Within each type there is a detailed description of the indicators and quotes from experts characterizing this performance indicator. It has been recorded that experts perceive the situation with the development of digital civic participation as dual, in which positive trends collide with barrier factors and conditions. Key factors-barriers have been identified: negative ideas about the effectiveness of digital activism, low awareness of the population about digital technologies and opportunities for participation, formalization and simulation of citizen activity, etc. Taking into account the results obtained, the prospects for future research are related to the study of the social effects of digital activism, identifying criteria for effectiveness in the assessments of the initiators and participants of activism, government officials and the media.
Fundamentals of strategic leadership of the digital ecosystem business model
Authors: Nikolaev Pavel Viktorovich
Published: November 2023

In the modern world, due to the development of Internet technologies, the activity of companies in the digital environment is becoming increasingly important. The most successful of them base their activities on a special kind of business model – the digital ecosystem, which is a unique combination of factors that allow the company to occupy a strategically leading position and be the most cost-effective. The paper characterizes and reveals the most characteristic features of the business model of the digital ecosystem, as well as clearly demonstrates the factors of competitiveness of digital ecosystems. Also, this work allows a deeper understanding of the essence of digital ecosystems as a key element of the modern economy, revealing their role in ensuring strategic leadership and sustainable competitiveness of companies in the digital age. Among the methods used were a comprehensive review of existing literature, case analysis, surveys and interviews with business leaders and experts in the field, a comparative analysis of case studies. The need for effective leadership in the digital age is widely recognized by both the business community and academia. However, there is still much to learn about the specific factors that determine successful leadership strategies in this new digital world. This research aims to identify the key features of successful leadership strategies in the digital age, focusing on the business models of digital ecosystems that allow you to take a leading position in the global market. The scientific novelty of this work lies in an in-depth analysis of the impact of digital technologies on the strategic leadership of companies and the identification of specific aspects that shape the success of digital ecosystems in a competitive global environment. This research aims to fill gaps in understanding the key factors that ensure strategic leadership in the era of digital transformation.
Typology of Gothic novels by Joseph Sheridan Le Fanu
Authors: Kurkina Nadezhda Valer'evna , Men'shchikova Mariya Konstantinovna
Published: November 2023

Joseph Sheridan Le Fanu is one of the most prominent representatives of the ghost story genre. His works were widely popular not only during the years of their publication, but also many years after. The subject of research in this article is the problem of creating a genre typology. Based on the material of Gothic novels (collections "Purcell Papers", "In a glass darkly", etc.) by the British writer of the XIX century Joseph Sheridan Le Fanu, the question of the optimal typological criterion is considered, which would allow creating an objective typology, the application of which would be possible when studying the works of other authors of Gothic minor prose of the second half of the XIX – early XX century. The methodological principles underlying this study take into account the achievements of cultural-historical, comparative, and structural-descriptive approaches. The novelty is associated with the absence of such a typology of Le Fanu's short stories, as well as with the fact that researchers prefer the novel form in the writer's work. However, this typology makes it possible to clarify some aspects of the development of Gothic minor prose both in the works of Le Fanu and in the works of other writers of this period. In addition, the typologization of Le Fanu's Gothic novels allows us to trace in more detail the change in the figurative system of Gothic short prose. Conclusions made as a result of the study: the objective typological criterion can be considered the specifics of the narrator's attitude to the category of the supernatural. Based on this criterion, the classic Gothic novel, the "scientific" Gothic novel, the humorous Gothic novel, the socio-psychological Gothic novel, the folklore-mythological Gothic novel are distinguished in Le Fanu's work.
The ideological world of the trilogy of the Mari writer N. Lekain «Iron Will», «In the Fire of the Great War», «Land of the Ancestors»
Authors: Belyaeva Tatyana Nikolaevna
Published: November 2023

An analysis of the themes, issues, ideas and pathos of the trilogy of the Mari writer Nikandr Lekain is the basis of this article. The novels «Iron Will» and «Land of Ancestors» depict the process of social and national revival of the previously oppressed Mari people. The depiction of the events of the beginning of the 20th century (Stolypin’s agrarian reform, the Great October Socialist Revolution, the Civil War, the NEP) takes place through the prism of the author’s worldview. The writer shows the conditions under which the process of formation of Soviet regime, the implementation of a new economic policy, the growth and formation of a new progressive Man, and the overcoming of the vestiges of the past in the minds of the Mari people took place. The novel «In the Fire of the Great War» by the former front-line soldier reveals the patriotism and heroism of the multinational Soviet people, manifested in the fight against the fascist invaders during the Great Patriotic War. This aspect is considered for the first time in Mari literary studies. The structural-semantic research method makes it possible to evaluate both the ideological world, the author’s worldview, and its individual poetic elements. Through the prism of the writer’s attention, the image of a resisting and fighting Soviet soldier is comprehensively depicted; as well as the heroic actions of the Yevsey’s, Ivan Zuev’s guerrilla warrior detachments in the enemy’s rear; the awful life under occupation of the Sosnovka’s village inhabitants; the cruelty of the German invaders; the spiritual squalor of the traitors. N. Lekain’s trilogy epically reveals the historical events of the late 19th – mid-20th centuries.
Retrograde jejunogastric intussusception
Authors: Senthilvelmurugan V. , Prasanth N. Raam , Arivarasan K. , Raj S. Aravinth
Published: November 2023

Retrograde intussusception pertains to the invagination of the intussusceptum in a direction opposite to normal peristalsis. Jejunogastric intussusception (JGI) is an infrequent complication linked to procedures such as gastrojejunostomy, Billroth II gastrectomy, and Roux-en-Y anastomosis. There are four types of JGI based on the type of intussuscepted bowel loop and two types based on clinical presentation. In its acute form, JGI presents as severe intestinal blockage, a mass in the left hypochondriac region, and the occurrence of hematemesis. In a chronic situation, it leads to the recurrent episodes of feeling full in the upper abdomen and experiencing vomiting because of intermittent and reversible intussusception. The gold standard investigation for diagnosis is a contrast-enhanced computed tomography (CECT) scan. Here, we describe a case of retrograde JGI in a patient who presented with the complaints of hematemesis. The CECT scan revealed the invagination of jejunal bowel loops into the stomach. This condition was treated surgically.
Cumulative sleep restriction and subsequent recovery sleep: Effects on subjective sleepiness, vigilance, and executive functions
Authors: Mishra Swapnil , Tripathy N. K. , Biswal Punyashlok , Raghunandan V.
Published: November 2023

Objective:

Cumulative partial sleep loss is more often practical eventually among aircrew. The sleep loss encountered on the weekdays is generally compensated by taking restorative sleep on the weekends. This study aimed to examine the subjective appreciation of sleepiness and cognitive performance pertaining to vigilance and executive functions during cumulative sleep restriction for a period of 05 days and then following 3 consecutive nights of recovery sleep.

Material and Methods:

In a repeated measures design, 14 healthy volunteers were longitudinally followed up twice on a day (morning and afternoon) on their subjective sleepiness (Stanford Sleepiness Scale), vigilance, and executive functions (Mackworth Clock Test and Stroop Test of Psychometric Evaluation Design for Aviators test battery, respectively) over a period of 5 days with 2 h of sleep restriction each night. These parameters were again assessed following 3 consecutive nights of restorative recovery sleep.

Results:

Subjective appreciation of sleepiness was significantly increased by accumulating sleep debt (F = 8.368, P < 0.001). Stroop Effect and Reaction Time did not show any significant changes; however, cumulative sleep loss significantly affected accuracy measures (F = 2.388, P = 0.04) and attention lapses (F = 2.816, P = 0.018). Following restorative sleep, the subjective sleepiness and accuracy scores did not show any significant difference from that of baseline. However, lapses continued to be significantly higher than the baseline values (P = 0.012).

Conclusion:

Cumulative sleep loss over a period of 5 days resulted in more sleepiness and a decrement in vigilance measures even though the executive functions remained intact. The persistence of attention lapses indicated incomplete recovery of vigilance functions following 3 days of restorative sleep.
Adie’s tonic pupil: Significance in aviators and aeromedical disposal
Authors: Borgohain Juhi , Raju A. V. K. , Waghray Ritesh
Published: November 2023

Adie’s tonic pupil is a benign, usually unilateral, pupillary syndrome, in which a larger than normal pupil responds minimally, if at all, to light, but constricts slowly and tonically to a near stimulus (light-near dissociation) and has cholinergic super-sensitivity. It induces impaired near vision, glare, photophobia, and difficulty with dark adaptation, which may not be conducive in a flying environment. A Weapon System Operator of a fighter aircraft with an isolated dilated pupil was assessed over approximately 3 years – right from the beginning until his condition became stable. His condition was not considered an absolutely disabling condition for aviation and he was finally retained in flying in the restricted medical category. The important aspects considered in the aeromedical assessment were – neurological assessment; ophthalmic issues such as tolerance to glare and visual acuity; anisocoria and the executive report on flying concerning visual response to bright sunlight, ability to read maps and MFDs, and ability to identify ground features and spot another ac in bright light conditions. The aviator did not have any neurological, traumatic, or systemic condition/Adie’s syndrome. The tonic pupil stabilized at 4 mm and there was an anisocoria of 2 mm. Light-near dissociation persisted. His executive report was uncomplimentary concerning spotting another aircraft in bright sunlight in the air-superiority fighter (which flies at a max speed of 2120 kmph) as his eyes were getting shut by the glare. However, he could read MFDs, maps, and pick up ground features comfortably and satisfactorily. Hence, considering that Navigation in a transport ac was his parent branch (max speed 452 kmph), he was advised a trial on that ac to assess his capabilities in performing Flt Nav duties. If successful, the organization could revert him back to his parent branch and original ac, thereby avoiding attrition of a valuable human resource. This case demonstrates that Adie’s tonic pupil is not always a disabling condition for military flying. Nevertheless, it has to be analyzed on a case to case basis. Aeromedical disposal of a potentially disqualifying case, having no reference in the available aeromedical guidelines.
Selective C-H Halogenation of Alkenes and Alkynes Using Flavin-Dependent Halogenases
Authors: Jiang Yuhua , Kim Ahram , Olive Cahmlo , Lewis Jared C.
Published: November 2023

Single component flavin-dependent halogenases (FDHs) possesses both flavin reductase and FDH activity in a single enzyme. We recently reported that the single component FDH AetF catalyzes site-selective bromination and iodination of a variety of aromatic substrates and enantioselective bromolactonization and iodoetherification of styrenes bearing pendant carboxylic acid or alcohol substituents. Given this inherent reactivity and selectivity, we explored the utility of AetF as catalyst for alkene and alkyne C-H halogenation. We find that AetF catalyzes halogenation of a range of 1,1-disubstituted styrenes, often with high stereoselectivity. Despite the utility of haloalkenes for cross-coupling and other applications, accessing these compounds in a stereoselective manner typically requires functional group interconversion processes, and selective halogenation of 1,1’-disubstituted olefins remains rare. We also establish that AetF and homologues of this enzyme can halogenate terminal alkynes. Mutagenesis studies and deuterium kinetic isotope effects are used to support a mechanistic proposal involving covalent catalysis for halogenation of unactivated alkynes by AetF homologues. These findings expand the scope of FDH catalysis and continue to show the unique utility of single component FDHs for biocatalysis.
Detection of a Jahn-Teller Mode as an Ultrafast Fingerprint of Spin-transition-induced Charge Transfer in CoFe Prussian Blue Analogue
Authors: Hervé Marius , Marekha Bogdan , Mazerat Sandra , Mallah Talal , Cammarata Marco , Matar Samir , Haacke Stefan , Leonard Jeremie , Collet Eric
Published: November 2023

Photoinduced spin transition is one of the fastest processes occurring in transition-metal-based molecules and materials, reaching down to tens of femtoseconds (1 fs = 1015 s). The underlying dynamics have been well characterized for mononuclear Fe(II) spin-crossover (SCO) complexes, where it was shown that the spin transition can induce coherent activation of metal-ligand breathing and bending vibrational modes, identified as the main reaction coordinates. While precise characterization of the femtosecond nuclear wave packet brings rich information on photoinduced spin transitions, it is scarcely explored in bimetallic Prussian Blue Analogues (PBAs). In this work, we performed transient absorption spectroscopy with sub-20 fs time resolution on the [Cs0.7Co(Fe(CN)6)0.9] PBA to unravel high-frequency coherent structural dynamics, which is interpreted as the activation of a low-symmetry CoN6 Jahn-Teller mode at 12 THz. This coherent fingerprint shows that the photoexcitation initially drives motion along the Jahn-Teller coordinate before the spin transition occurs, i.e., over less than 50 fs. These results are in stark contrast with conventional activation of fully-symmetric breathing modes reported for several SCO compounds, thus providing new insights on the ultrafast spin-transition-induced charge transfer dynamics in PBAs.
LC-ESI-HRMS - lipidomics of phospholipids – Characterization of extraction, chromatography and detection parameters
Authors: Rund Katharina , Carpanedo Laura , Lauterbach Robin , Wermund Tim , West Annette , Wende Luca , Calder Philipp , Schebb Nils Helge
Published: November 2023

Lipids are a diverse class of molecules involved in many 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 the 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 a sufficient number of both data points across the chromatographic peaks, as well as MS2 spectra. Analysis was carried out in positive and negative ionization mode enabling the detection of a broader spectrum of lipids and to support the structural characterization of lipids. Optimal sample preparation of biological samples was achieved by liquid-liquid extraction using MeOH/MTBE resulting in an excellent extraction recovery >85% with an intra-day and inter-day variability <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.
Exogenous Photocatalyst-Free Aryl Radical Generation from Diaryliodonium Salts and use in Pd-Catalyzed C–H Arylation
Authors: Galicia Jonathan , McDonald Nicholas , Bennett Christopher , He Jiajun , Glossbrenner Mark , Romero Erik
Published: November 2023

While photocatalysts are generally responsible for radical generation from bench stable diaryliodonium salts, recent reports have emerged exhibiting photocatalyst-free radical generation using select Lewis bases as activators. Herein, we demonstrate 1) the ability of numerous Lewis bases to enable light-driven radical generation and 2) these radicals can be captured by transition-metals for coupling reactions. These results are the first step toward developing new organometallic aryl radical coupling reactions without photocatalysts.
Homo- and Hetero-Recyclable Polyesters with High Refractive Index from CO2, 1,3-Butadiene and Thiols
Authors: Zhang Zhuorui , Shen Ting , Chen Kaihao , Zeng Junjie , Ling Jun , Ni Xufeng
Published: November 2023

α-Ethylidene-δ-vinyl-δ-valerolactone (EVL) is the only intermediate to synthesize copolymers of CO2 with 1,3-butadiene whose ring-opening polymerization (ROP), however, is obstructed by the tiglate group. The saturation of the conjugated double bond is essential to the living ROP of EVL, while previous reports involve irreversible hydrogenation. In the contribution, EVL derivatives are synthesized through Michael addition reaction to saturate the conjugated double bond as well as introduce various groups to synthesize polyesters with tunable glass-transition temperatures (Tg) from -45 °C to 3 °C and excellent refractive index between 1.64 and 1.85. Living and controlled polymerizations lead to polyesters with designable number average molecular weights (Mn = 6.9-12.8 kg∙mol-1) and narrow dispersities (Đ = 1.08-1.19). The obtained polyesters are able to be recycled to the corresponding monomers which can prepare comparable polymers with identical side groups, realizing the homo-recycling. The monomers are capable of being recycled to EVL and thiols through retro-Michael addition reaction, and then the recycled EVL can be re-functionalized to generate a new monomer which produces a polyester with another side group, fulfilling the hetero-recycling. We propose an “addition-elimination-re-addition” strategy for EVL derivatives and the corresponding polyesters.
Controlling the Nonadiabatic Dynamics of the Charge-Transfer Process with Chirped-Pulses: Insights from a Double-Pump Time-Resolved Fluorescence Spectroscopy Scheme.
Authors: Soh Jia Hao , L.C. Jansen Thomas , Palacino-González Elisa
Published: November 2023

The manipulation of the ultrafast quantum dynamics of a molecular system can be achieved through the application of tailored light fields. This has been achieved in many ways in the past. In our present investigations, we show that it is possible to exert specific control over the nonadiabatic dynamics of a generic model system describing ultrafast charge-transfer within a condensed dissipative environment by using frequency-chirped pulses. By adjusting the external photoexcitation conditions, such as the chirp parameter, we show that the final population of the excitonic and charge-transfer states can be significantly altered, thereby influencing the elementary steps controlling the transfer process. Besides, we introduce an excitation scheme based on double-pump time-resolved fluorescence spectroscopy using chirped-pulse excitations. Here, our findings reveal that chirped excitations enhance the vibrational system dynamics as evidenced by the simulated spectra, where a substantial signal intensity dependence on the chirp is observed. Our simulations show that chirped pulses are a promising tool for steering the dynamics of the charge-transfer process towards a desired target outcome.
Pore Structure Compartmentalization for Advanced Characterization of Metal-Organic Framework Materials
Authors: Parashar Shivam , Neimark Alexander V.
Published: November 2023

Metal-Organic Frameworks (MOFs) are nanoporous crystals which are widely used as selective adsorbents, separation membranes, catalysts, gas and energy storage media, and drug delivery vehicles. The unique adsorption and transport properties of MOFs are determined by their complex three-dimensional (3D) networks of pores, cages, and channels, that differ in size, shape, and chemical composition. While the morphological structure of MOF crystals is known, practical MOF materials are rarely ideal crystals. They contain secondary phases, binders, residual chemicals, and various types of defects. It is of paramount importance to evaluate the degree of crystallinity and accessibility of different pore compartments to adsorbing guest molecules. To this end, we recently suggested the method of fingerprint isotherms based on the comparison of the experimentally measured adsorption isotherms and theoretical isotherms on ideal MOF crystals produced by Monte Carlo (MC) simulations and decomposed with respect to different pore compartments. In this work, we develop an automated algorithm of pore network compartmentalization that is a prerequisite for calculations of the fingerprint isotherms. The proposed algorithm partitions the unit cell into realistically shaped compartments based on the geometric pore size distribution. The proposed method is demonstrated on several characteristic systems, including Cu-BTC, IRMOF-1, UiO-66, PCN-224, and ZIF-412 and 56 structures from the CoRE MOF database.
Vyvolanie scitlivenia na koróziivzdornej oceli 1.4845
Authors:   University of Žilina, Kaličiak Samuel , Kantoríková Elena , Bolibruchová Dana
Published: November 2023

The experiment is focused on the influence of heat treatment, solution annealing and subsequent sensitization of stainless steel 1.4845. In the experiment, a suitable thermal cycle of solution annealing and subsequent sensitization is designed. Subsequent comparisons of the microstructure and hardness of steel 1.4845 before and after the proposed heat treatment.
Posúdenie stability lesného kolesového traktora vybaveného hydraulickou rukou
Authors:   University of Žilina, Dižo Ján , Blatnický Miroslav , Ishchuk Vadym , Lovska Alyona , Fidrik Filip
Published: November 2023

Wheeled forests tractors are inseparable part of a forest economy. Wheeled forests tractors serve for logging of logs in forests. Current wheeled forests tractors are usually equipped with hydraulic arms, which allow to expand the utility of such tractors. A tractor with a hydraulic arm can handle with wood logs without a need additional forest machine, which helps to reduce costs. On the other hand, it is necessary to analyse tractors abilities, which has such an additional equipment. This article is focused on assessment of stability of a heeled forest tractor, which is equipped by such a hydraulic arm. As the hydraulic arm changes the centre of gravity of an entire tractor, mainly with the load, safe operation of the tractor needs to know limit conditions of stability under the maximal load and in the given slope inclination.