bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper acquisition is essential for plant colonization and virulence in a root-infecting vascular wilt fungus
Authors: Palos-Fernández Rafael , Aguilar-Pontes María Victoria , Puebla-Planas Gema , Berger Harald , Studt-Reinhold Lena , Strauss Joseph , Di Pietro Antonio , López-Berges Manuel Sánchez
Published: November 2024

Plant pathogenic fungi provoke devastating agricultural losses and are difficult to control. How these organisms acquire micronutrients during growth in the host environment remains poorly understood. Here we show that efficient regulation of copper acquisition mechanisms is crucial for plant colonization and virulence in the soilborne ascomycete Fusarium oxysporum, the causal agent of vascular wilt disease in more than 150 different crops. Using a combination of RNA-seq and ChIP-seq, we establish a direct role of the transcriptional regulator Mac1 in activation of copper deficiency response genes, many of which are induced during plant infection. Loss of Mac1 impaired growth of F. oxysporum under low copper conditions and abolishes pathogenicity on tomato plants and on the invertebrate animal host Galleria mellonella. Importantly, overexpression of two Mac1 target genes encoding a copper reductase and a copper transporter was sufficient to restore virulence in the mac1 mutant background. Our results establish a previously unrecognized role of copper reduction and uptake in fungal infection of plants and reveal new ways to protect crops from phytopathogens.
Phytochemical screening, phenolic and flavonoid contents, psilocybin, antioxidant, and acetylcholinesterase inhibition activities of the aqueous extract from the fungi Cyathus striatus, Laternea dringii, and Marasmius haematocephalus
Authors: Silva Douglas Ferreira da , Menezes Filho Antonio Carlos Pereira de , Melo Aurélio Ferreira , Sharma Porshia , Machado Tullyo Henrique Lima , Machado Vanêcia Oliveira Cunha , Ventura Matheus Vinícius Abadia
Published: November 2024

Various families of mushrooms contain important phytochemicals with significant potential. This study aimed to investigate the phytochemical prospecting, presence of psilocybin, antioxidant activities, and acetylcholinesterase inhibition in aqueous extracts of Cyathus striatus, Laternea dringii, and Marasmius haematocephalus. Aqueous extracts were produced from mushrooms, and phytochemical groups were determined. The total phenolic and flavonoid content, DPPH reduction capacity, and FRAP were quantitatively determined. The acetylcholinesterase inhibition assay was performed, and the results were expressed as AChE inhibition percentages. Phytochemical groups such as flavonoids, phenolics, alkaloids, organic acids, and aliphatic compounds were positively detected. For phenolics, the extracts showed values of 208.44, 134.11, and 100.09 mg GAE g TPC-1; for flavonoids, values of 45.12, 56.06, and 39.71 mg QE g TFC-1. The FRAP reduction capacity showed values of 7.56, 14.43, and 4.15 µM TE g-1, while for DPPH, the values were 100.07, 88.12, and 133.65 µg mL-1. Low, medium, and strong AChE inhibition activity was observed with values of 43.11%, 68.53%, and 77.14%, respectively, for C. striatus, L. dringii, and M. haematocephalus. The aqueous extracts of Cyathus striatus, Laternea dringii, and Marasmius haematocephalus exhibited various phytomolecules groups with potential biological activities observed in this study.
re-harvest application of 2-(3-chlorophenoxy) propionic acid on pineapple plants
Authors: Oliveira Fernanda Soares , Maia Victor Martins , Pegoraro Rodinei Facco , Carvalho Danielle Mota , Souza Mirna Ariane Taveira de Sousa , Mota Mauro Franco Castro
Published: November 2024

The application of plant regulators such as exogenous auxin may provide effects on the translocation of carbohydrates to plant sinks, which may result in larger parthenocarpic fruits. The objective of the study was to evaluate the effects of the application of 2-(3-chlorophenoxy) propionic acid on the growth and quality of pineapple fruits. The experiment was carried out in a randomized block design. After floral induction, 2-(3-chlorophenoxy) propionic acid (CPA) was applied directly on the inflorescences at the following doses: 0 mg L-1; 40.0 mg L-1; 80.0 mg L-1; 120.0 mg L-1 and 160.0 mg L-1. Growth evaluations continued until 84 days after application, measuring fruit length (cm) with and without crown, crown length (cm), leaf D dry matter, fruit weight with and without crown (g), calculating if also, the absolute and relative growth rates. The post-harvest and quality characteristics of the fruits were also evaluated, as well as the harvest index. The application of CPA significantly reduces the length and weight of the crown of the fruits, however, the exogenous application of auxin provided an increase in the weight of the fruit. Regarding the post-harvest analysis, the application of CPA reduced the content of soluble solids in the fruit pulp.
Estmation of time interval of the pig carrion by beetle fauna succession in southeast, Nigeria
Authors: Uhuo Cosmas Augustus , Ukwueze Callistus Kelechi , Okeke Tobechukwu Ebele , Nwele David Ekene , Nwokporo Nkiruka Regina
Published: November 2024

Background: Beetles (Coleoptera) have been recognized as providing significant entomological evidence in the medico-legal field, particularly with reference to dry human remains. The information collected from carrion beetles in Abakaliki will add to the global data base to assist coronary investigators unravel mysteries surrounding suspicious death in Nigeria. A study was carried out to investigate the succession of beetle fauna in a decomposing pig carrion in Abakaliki Ebonyi State. The study was conducted on poisoned pigs using sniper at the pericardium region and beetles were collected using standard entomological methods. Results: The study lasted twenty-two days with notable characteristic changes observed at the five decomposition waves. A total of five families, and twelve species were collected at various succession pattern of decomposition. The results showed that Buphonella species and Necrubia species were recorded at high interval among the decomposition stages, While Dermestidea recorded the highest family observed. The result also revealed that most beetles collected arrived at the dry decay stage with few attendant patterns at earlier stages. Conclusion: However, this study confers the species of Coleopteran insects of forensic importance and gives a background information about their succession in relation to decomposition stages. This could be used to determine the post mortem interval of human corpse based upon knowledge of the fauna.
Older adult learners as digital citizens: Their needs and challenges while participating in an online master’s programme
Authors: Mouwers-Singh Constance , Arendse Agnetha
Published: November 2024

This article explores the learning journeys of older adult learners (OALs) enrolled in an online education master’s programme. Today, many OALs are enrolling in various online programmes. A study by the first author explored the ways in which these OALs identify with  being digital citizens, and also investigated their needs and challenges. The capabilities approach was used as the theoretical framework and provided a lens through which the participants’ digital experiences could be explored most appropriately. The objectives of the study were: (a) to identify the needs and challenges of OALs participating in an online master’s programme as regards digital literacy, technical support and learning resources; and (b) to explore their online learning experiences and challenges, including digital literacies and the way OALs consider themselves as digital citizens. The qualitative nature of this study included a narrative enquiry. Using open-ended, semi-structured interviews, the eight participants with an average age of 49 shared detailed perspectives about their online learning experiences, digital literacies, and the way they view themselves as digital citizens. The findings reveal that OALs need specific levels of learning assistance, intergenerational learning, collaborative learning, mentorship and support when using digital technologies.
Multi-criteria approach for weights definition of sustainability indicators in the swine supply chain
Authors: Kruger Silvana , Trojan Flavio , Zanin Antonio , Lizot Mauro , Afonso Paulo
Published: November 2024

Goal: This study presents a four-steps methodology for the definition of the weights of sustainable indicators in the Swine Supply Chain (SSC) considering the Triple Bottom-Line (TBL) perspective.
Design/Methodology/Approach: The methodology proposed was based on the Bellagio principles that guide the definition of importance levels for TBL criteria. It was applied to the swine supply chain using Saaty’s scale and information obtained from managers of two agribusiness companies, adjusted by the AHP method.
Results: The results showed the relevance of an appropriate definition of the preferences of decision-makers to decide on the best actions towards environmental, economic, and social sustainability.
Limitations: The limitations of the proposed model are mainly its subjective nature. Despite being necessary in multi-criteria methods, it could be a limitation if more quantitative indicators are relevant or demanded. Nevertheless, the proposed methodology also provides a quantitative perspective, as a result of using the Saaty scale.
Practical implications: The definition and application of importance levels within a TBL-based model can help managers to prioritize environmental, social, and/or economic dimensions under a large diversity of alternatives toward more sustainable scenarios. The AHP method used in this work is a hierarchy method, particularly appropriate for defining weights that are essentially compensatory by nature.
Originality/value: The correct definition and weight of the different dimensions, sub-dimensions, and respective indicators is currently one relevant gap in the literature, limiting the design and prioritization of corrective actions in each stage of the SSC and in the different dimensions of the TBL.
Symptom clusters and resting cardiovascular autonomic measures in adolescents: From acute concussion to recovery
Authors: Ji Wenjie , Chizuk Haley M. , Leddy John J. , Sisto Sue A. , Haider Mohammad N.
Published: November 2024

Sport‐related concussion (SRC) is associated with cardiovascular autonomic nervous system (ANS) dysfunction. This study examines resting cardiovascular ANS activity in adolescents with SRC compared to controls early post‐injury and after clinical recovery, analyzing its correlation with symptom severity and recovery outcomes. Cardiovascular ANS function was evaluated using heart rate variability (HRV), systolic blood pressure variability (SBPV) and baroreflex sensitivity (BRS). Symptoms were assessed via the Post‐Concussion Symptom Scale, and recovery outcomes were categorized by recovery duration. Following acute SRC, no significant differences in HRV, SBPV or BRS were found between SRC and control groups, nor between those with delayed or normal recovery. Post‐recovery, SRC participants had higher low frequency (LF) SBPV than controls and their initial assessment. When concussed participants were symptomatic, LF SBPV correlated directly with overall, cognitive, and fatigue symptom severity, while high frequency (HF) HRV inversely correlated with affective symptoms (Spearman's rho: 0.4–0.6). Resting cardiovascular ANS function remains unchanged in adolescent athletes acutely after SRC, suggesting it has limited diagnostic and prognostic potential. Although some correlations between individual symptom domains and ANS activity were observed, they were not significantly different from asymptomatic controls, limiting the ability to interpret these findings.
Online makespan minimization for MapReduce scheduling on multiple parallel machines
Authors: Zheng Quanchang , Zhao Yueyang , Wang Jiahe
Published: November 2024

In this work, we investigate the online MapReduce processing problem on

m

m

uniform parallel machines, aiming at minimizing the makespan. Each job consists of two sets of tasks, namely, the map tasks and the reduce tasks. A job’s map tasks can be arbitrarily split and processed on different machines simultaneously, while its reduce tasks can only be processed after all its map tasks have been completed. We assume that the reduce tasks are preemptive, but cannot be processed on different machines in parallel. We provide a new lower bound for this problem and present an online algorithm with a competitive ratio of

2
−

1

m

2-\frac{1}{m}

(

m

m

is the number of machines) when the speeds of the machines are 1.
Green energy using oscillatory baffled reactors: advances in biodiesel production from high free fatty acid karanja oil
Authors: Ganvir Vinod , Belkhode Pramod , Kurve Anjali , Shelare Sagar , Maheshwary Prashant , Sharma Shubham , Dwivedi Shashi Prakash , Kumar Sandeep , Bisht Yashwant Singh , Abbas Mohamed
Published: November 2024

The global demand for sustainable and ecologically friendly energy sources has spurred biodiesel research. Civilization, urbanization, and population growth have drastically boosted transportation energy consumption. Energy demand is causing fossil fuel crises. Replace petroleum diesel to solve energy and environmental problems. Biofuels have very vast scope in the area of energy sector. Karanja oil, derived from the seeds of the Karanja tree (Pongamia pinnata), is a promising biodiesel feedstock due to its high Free Fatty Acid content. This study uses Oscillatory Baffled Reactor (OBR) to produce biodiesel from Karanja oil. The feedstock is high-FFA Karanja oil trans-esterified in two steps. In OBR, reaction time is only 15 min, whereas in conventional reactor it takes 1–2 h to produce biodiesel. Optimizing biodiesel synthesis involved varying H2SO4 concentrations from 1 vol% to 5 vol% and 0.3 to1.0 wt% of NaOH concentration for first and second step respectively. Oil-to-alcohol molar ratios 1:6, 1:9 and 1:12. Optimization occurs at 1:12 oil-to-alcohol ratio, 1 vol% H2SO4 catalyst, and 0.6 wt% NaOH catalyst. Studies have also examined how catalyst concentration and oil: alcohol molar ratio affect biodiesel conversion and physical qualities such kinetic viscosity, specific gravity, and acid value. This study shows that OBR can increase biodiesel production from high-FFA Karanja oil, which further opens up opportunities for additional study and improvement.
Die Pferde von Amnisos. Ein Wendepunkt in der Geschichte des bronzezeitlichen Kreta?
Authors: Tausend Klaus
Published: November 2024

Im mykenischen Palast von Knossos enthält der so genannte „Raum der Wagentafeln“ unter anderem mehr als 170 blattförmige Tafeln, die Sc-Serie. Jede Tafel zeigt einen Personennamen und eine unterschiedliche Anzahl von Ideogrammen: Streitwagen, Rüstung, Pferde. Es lässt sich zeigen, dass die genannten Personen die Gegenstände und Tiere nicht an den Palast liefern sollen, sondern vom Palast mit Rüstung, Wagen und Pferden ausgestattet werden sollen. Es scheint, dass die genannten Personen ihre Ausrüstung oder zumindest Teile davon verloren haben. Betrachtet man die Verluste, so ist die hohe Anzahl der verlorenen Pferde erstaunlich. Eine mögliche Lösung ist, dass die auf den Tafeln verzeichneten Verluste das Ergebnis einer Schlacht sind, die von Streitwagen in der Nähe des Hafens von Amnisos geschlagen wurde.
Zur Frage der Lokalisierung des sasanidischen Vizekönigtums Gēlān im 3. Jhd. n. Chr.
Authors: Mosig-Walburg Karin
Published: November 2024

In der Inschrift Šāpūrs I. in Naqš-i Rustam (ŠKZ) wird ein Gēlān-šāh (König von Gēlān/der Gelen) namens Bahrām genannt, mit großer Wahrscheinlichkeit ein Sohn Šāpūrs I. Dem Zeugnis der Quellen folgend, die von der vorsasanidischen bis in die nachsasanidische Zeit den südwestlichen Rand des Kaspischen Meeres als Siedlungsraum der Gelen bezeugen, wie auch die Existenz einer Provinz Gēlān eben dort in spätsasanidischer Zeit, wurde das Vizekönigtum Gēlān von der Forschung seit jeher am Kaspischen Meeres verortet. In jüngerer Zeit plädiert jedoch Rika Gyselen für eine Verortung im Osten des Sasanidenreiches, zum Teil verbunden mit Spekulationen bezüglich einer förderlichen Wirkung der vermeintlichen Herrschaft Bahrāms über Gelen im Osten bei seiner Herrschaftsübernahme im Jahr 273. Die für das 6. und 7. Jahrhundert durch Quellen bezeugte Provinz Gēlān siedelt Gyselen dagegen am Kaspischen Meer an. Auf der Basis der Auswertung relevanter Quellen zu Gelen und Gēlān von der vorsasanidischen bis in nachsasanidische Zeit sowie einer ausführlichen Analyse der von Gyselen in verschiedenen Publikationen sukzessive zugunsten ihrer Hypothese vorgebrachten Argumente wird gezeigt, daß ihre Verortung des Vizekönigtums Bahrāms im Osten des Sasanidenreiches und damit jegliche daran anschließende Spekulationen der Grundlage entbehren. Abschließend wird die Frage der Identität der Gelen angesprochen, die in den 280er Jahren den Aufstand des Hormizd/Ormies gegen Bahrām II. unterstützten. Es wird die Ansicht vertreten, daß es sich höchstwahrscheinlich um Söldner aus Gēlān am Kaspischen Meer gehandelt hat.
Comparative analysis of 3D-printed and freeze-dried biodegradable gelatin methacrylate/ poly‐ε‐caprolactone- polyethylene glycol-poly‐ε‐caprolactone (GelMA/PCL-PEG-PCL) hydrogels for bone applications
Authors: Khoeini Roghayeh , Roshangar Leila , Aghazadeh Marziyeh , Soltani Saeideh , Soltani Somaieh , Danafar Hossein , Hosseinpour Rasoul , Davaran Soodabeh
Published: November 2024

Gelatin methacrylate (GelMA) is a photo-cross-linkable biopolymer. A combination of GelMA with biodegradable polyesters such as PCL (poly‐ε‐caprolactone) and their triblock derivatives improve the mechanical properties of GelMA. PCL-PEG-PCL (PCEC) was synthesized using ring-opening polymerization of ε-caprolactone in the presence of polyethylene glycol (PEG). The GelMA- PCEC was fabricated using freeze-drying and 3D printing and their porosity, mechanical properties, and swelling behavior were investigated. Human dental pulp stem cells were cultured on the scaffolds for a period of 14 days and cell adhesion was evaluated by scanning electron microscopy. Cell viability was analyzed by MTT and osteogenic differentiation was evaluated by Alizarin red S. Results showed that the 3D-printed scaffold had higher water absorption rate, retaining its structure up to a strain of 0.2 %, and a higher Young’s modulus compared to the freeze-dried scaffold. In terms of cell viability, the 3D-printed scaffold outperformed the freeze-dried scaffold with a percentage of 86 % and 63 % viability respectively. Moreover, the 3D-printed scaffold exhibited better osteodifferentiation with calcium deposition. Overall, these findings suggest that the 3D-printed scaffold may have advantages over the freeze-dried scaffold in tissue engineering applications that require high water absorption, elasticity, and cell viability. The fabricated scaffolds provided suitable cell proliferation.
The Icelandic Mutation (APP-A673T) Is Protective against Amyloid Pathology In Vivo
Authors: Shimohama Sho , Fujioka Ryo , Mihira Naomi , Sekiguchi Misaki , Sartori Luca , Joho Daisuke , Saito Takashi , Saido Takaomi C. , Nakahara Jin , Hino Tomohito , Hoshino Atsushi , Sasaguri Hiroki
Published: November 2024

A previous epidemiological study in Northern Europe showed that the A673T mutation (Icelandic mutation) in the amyloid precursor protein gene (APP) can protect against Alzheimer's disease (AD). While the effect of the A673T mutation on APP processing has been investigated primarily in vitro, its in vivo impact has not been evaluated. This is mainly because most existing AD mouse models carry the Swedish mutation. The Swedish and Icelandic mutations are both located near the β-cleavage site, and each mutation is presumed to have the opposite effect on β-cleavage. Therefore, in the AD mouse models with the Swedish mutation, its effects could compete with the effects of the Icelandic mutation. Here, we introduced the A673T mutation intoAppknock-in mice devoid of the Swedish mutation (AppG-Fmice) to avoid potential deleterious effects of the Swedish mutation and generatedAppG-F-A673Tmice. APP-A673T significantly downregulated β-cleavage and attenuated the production of Aβ and amyloid pathology in the brains of these animals. The Icelandic mutation also reduced neuroinflammation and neuritic alterations. Both sexes were studied. This is the first successful demonstration of the protective effect of the Icelandic mutation on amyloid pathology in vivo. Our findings indicate that specific inhibition of the APP-BACE1 interaction could be a promising therapeutic approach. Alternatively, the introduction of the disease-protective mutation such as APP-A673T using in vivo genome editing technology could be a novel treatment for individuals at high risk for AD, such as familial AD gene mutation carriers andAPOEε4 carriers.
Clinical features and search for genetic determinants of postprandial hypoglycaemia
Authors: Ren Qian , Han Xueyao , Gong Siqian , Zhang Simin , Ba Tianhao , Zhao Yilin , Li Yating , Wang Yan’ai , Zhou Xianghai , Li Yufeng , Ji Linong
Published: November 2024

Objective

To test whether postprandial hypoglycaemia is an extreme and repeatable phenotype of glucose metabolism. We also explored the genetic determinants of this phenotype.

Design and methods

We conducted this study using data from the Pinggu Metabolic Disease Study database (n = 3,345). We selected subjects after an oral glucose tolerance test (OGTT) (2 h glucose < 3 mmol/L) and compared their clinical features with those of subjects with normal glucose tolerance (NGT). In addition, we selected 75 subjects as a super-healthy control group. Whole-exome sequencing (WES) was performed on subjects with postprandial hypoglycaemic and super-healthy controls. We also evaluated several candidate genes believed to be important in pancreatic hypoglycaemia.

Results

We found 13 participants (0.39%) who had an OGTT (2 h glucose < 3 mmol/L). Ten of these patients were men (76.9%). All 13 participants had insulin >3 μU/mL when postprandial blood glucose levels were <3 mmol/L. WES analysis identified one gene, paternally expressed 3 (PEG3), which had three rare mutations in four patients (30.8%). Minor allele frequencies of rare PEG3 mutations were significantly higher in subjects with postprandial hypoglycaemia than in super-healthy controls. Among the four subjects with PEG3 gene mutations, 71.4% were men, and their body mass index was significantly lower than that of the NGT group.

Conclusions

Postprandial hypoglycaemia is an extreme and reproducible phenotype in the general population. PEG3 mutations may represent a potential genetic aetiology for postprandial hypoglycaemia. Further research with larger and more diverse populations and a broader genetic focus is needed to understand the genetic basis of postprandial hypoglycaemia.
ТРАНСФОРМАЦИЯ СПЕКТРАЛЬНЫХ ХАРАКТЕРИСТИК ФЕМТОСЕКУНДНОГО ЛАЗЕРНОГО ИМПУЛЬСА ПРИ РАСПРОСТРАНЕНИИ В АТМОСФЕРЕ
Authors: В.Е. ПРОКОПЬЕВ , Д.М. ЛУБЕНКО
Published: November 2024

Приводятся результаты экспериментальных исследований по изучению механизмов трансформации спектра фемтосекундного лазерного импульса, возникающего при его распространении в атмосфере и в чистом молекулярном азоте в режиме филаментации. При этом спектральное уширение излучения накачки является результатом совместного действия стоксового вынужденного комбинационного рассеяния на вращательных переходах молекул азота воздуха, когерентного антистоксова рассеяния света и параметрического четырехволнового смешения. Уширение происходит в широком диапазоне: от 350 до 1100 нм. Исследование таких процессов в перспективе позволит создавать высокоэффективные источники белого света для атмосферной спектроскопии и дистанционного зондирования.

Experimental results and the analysis of the reasons for the transformation of spectral parameters of a femtosecond laser pulse propagating in atmosphere and in pure molecular nitrogen are presented. The experiment was carried out under aberration focusing conditions. It is shown that the main contribution to the anti-Stokes spectrum broadening is made by cascade parametric four-wave mixing initiated in the filamentation domain by stimulated Raman Stokes scattering on rotational transitions of nitrogen.
ОСОБЕННОСТИ РАСПРЕДЕЛЕНИЯ ПОЛЯ ОБЩЕГО СОДЕРЖАНИЯ ОЗОНА НА ТЕРРИТОРИИ РОССИИ, ЕГО ВНУТРЕННИЕ ВЗАИМОСВЯЗИ И РАССОГЛАСОВАНИЕ ДАННЫХ
Authors: О.Е. БАЖЕНОВ , А.В. ЕЛЬНИКОВ , В.А. ЛОГИНОВ
Published: November 2024

Исследования поля общего содержания озона (ОСО) - одна из важных проблем атмосферной оптики. В работе на основе данных прибора Ozone Monitoring Instrument (OMI), установленного на борту космической платформы Aura, анализируется пространственно распределение ОСО над территорией России. Результаты наблюдений для отдельных областей (пунктов) представлены в виде временных рядов ОСО, которые охватывают период наблюдений с января 2005 г. по декабрь 2022 г. Выявлены интегральные (без учета сезонных вариаций) широтно-долготные особенности распределения ОСО на исследуемой территории; вычислены коэффициенты корреляции между рядами для разных пунктов; исследована их взаимосвязь в зависимости от расстояния между пунктами; сформирована пространственная автокорреляционная функция и оценены размеры пространственных неоднородностей поля ОСО. Проанализировано пространственное рассогласование данных с помощью параметра, представляющего собой меру стандартного отклонения от среднего рассогласования. Результаты работы дают представление о масштабах пространственной взаимосвязи поля ОСО и могут быть использованы для уточнения оптически активной компоненты атмосферы (ОСО) при разработке прогностических моделей погоды и изменения климата.

The study of the field of total ozone column (TOC) is one of the important problems of atmospheric optics. In this paper, the spatial distribution of TOC over the Russian territory is analyzed based on Aura/OMI (Ozone Monitoring Instrument) data. The observation results for individual areas (points) are presented in the form of TOC time series, which cover the observation period from January 2005 to December 2022. Integral (excluding seasonal variations) latitude-longitude features of TOC distribution over the territory under study are revealed; correlation coefficients between the TOC series for different points are calculated; their relationship is studied depending on the distance between the points; the spatial autocorrelation function is derived and the sizes of spatial inhomogeneities of the TOC field are estimated. The spatial mismatch of the data is analyzed using a parameter which is a measure of the standard deviation from the average mismatch. The results of the work provide an idea of the scale of the spatial correlations in the TOC field and can be used for clarifying the optically active component of the atmosphere when developing weather and climate change prognostic models.
СИСТЕМА ВОЗБУЖДЕНИЯ АКТИВНЫХ СРЕД НА ПАРАХ МЕТАЛЛОВ ДЛЯ РЕАЛИЗАЦИИ НЕТИПИЧНЫХ РЕЖИМОВ ГЕНЕРАЦИИ
Authors: Н.В. КАРАСЕВ , В.О. ТРОИЦКИЙ , В.А. ДИМАКИ , М.В. ТРИГУБ
Published: November 2024

Проблема расширения функциональных возможностей лазеров в целом, и на парах металлов в частности, остается актуальной. Ее решение связано как с исследованием кинетики процессов в лазерных средах, так и с разработкой новых систем возбуждения. Представлены результаты создания и применения системы возбуждения активных сред на парах металлов, которая состоит из трех источников накачки, системы синхронизации и программного обеспечения. Высоковольтные импульсы формируются тремя независимыми инверторами, коммутация осуществляется с помощью тиратронов. Рассмотрены основные возможности системы и перспективы ее использования для реализации нетипичных режимов генерации. Экспериментально удалось установить, что в смеси CuBr + Ne + HBr генерация сохраняется при временах релаксации порядка 5000 мкс.

Expansion of the functional capabilities of lasers in general and metal vapor lasers in particular is a relevant problem. Its solution is associated with both the study of the kinetics of processes in laser media and the development of new excitation systems. In this work, a system for exciting metal vapor active medium is suggested. It consists of three pumping sources, a synchronization system, and software. High voltage pulses are generated by three independent inverters; thyratrons are used as switches. The main capabilities of the system and the prospects for its use for implementing non-typical lasing modes are considered.
ОСОБЕННОСТИ ИНИЦИИРОВАНИЯ И РАСПРОСТРАНЕНИЯ ДЕТОНАЦИИ В ЦИЛИНДРИЧЕСКОМ ЗАРЯДЕ ИЗ ТАТБ
Authors: Н.А. ВОЛОДИНА , А.В. ЕРАСТОВ , П.В. ЗАБУСОВ , М.Н. КИРЮХИНА , К.Н. ПАНОВ , В.Б. ТИТОВА , М.О. ШИРШОВА
Published: November 2024

Рентгенографическим методом исследован процесс распространения детонации в полукольцевых зарядах из пластифицированного ТАТБ со стальной оболочкой внутри при инициировании нормальной детонации по линии на наружной поверхности заряда. В экспериментах определена форма фронта детонационной волны рентгенографическим методом в разные моменты времени. В опытах зафиксировано влияние на форму детонационного фронта слоя из пластического взрывчатого вещества на основе гексогена, расположенного на поверхности основного заряда и имеющего скорость детонации на 10 % выше, чем у ТАТБ. Экспериментальное положение и форма фронта детонационной волны в заряде ТАТБ цилиндрической формы не описываются законами геометрической оптики (принцип Гюйгенса) из-за особенностей инициирования детонации на начальном участке и наличия стальной оболочки. Проведено численное моделирование экспериментов по методике ЛЭГАК с использованием макроскопической кинетики детонации. Получена схожая с экспериментом картина инициирования и распространения детонации в заряде ТАТБ. Проведен расчетно-теоретический анализ особенностей распространения детонационной волны.

The process of detonation propagation in semi-annular charges made of plasticized TATB with a steel shell inside during initiation of normal detonation along a line on the outer surface of the charge was studied using the X-ray method. In the experiments, the shape of the detonation wave front was determined using the X-ray method at different moments in time. The experiments recorded the effect of a layer of plastic explosive based on hexogen located on the surface of the main charge and having a detonation velocity 10% higher than that of TATB on the shape of the detonation front. The experimental position and shape of the detonation wave front in a cylindrical TATB charge are not described by the laws of geometric optics (Huygens principle) due to the peculiarities of detonation initiation in the initial section and the presence of a steel shell. Numerical modeling of the experiments was carried out using the LEGAK technique using macroscopic detonation kinetics. A similar to the experimental picture of the initiation and propagation of detonation in the TATB charge was obtained. A theoretical analysis of the features of the propagation of the detonation wave was carried out.
ОКИСЛЕНИЕ БОРА, МОДИФИЦИРОВАННОГО ПЕНТОКСИДОМ ВАНАДИЯ
Authors: В.Г. ШЕВЧЕНКО , В.Н. КРАСИЛЬНИКОВ , Д.А. ЕСЕЛЕВИЧ , А.В. КОНЮКОВА , О.Г. РЕЗНИЦКИХ
Published: November 2024

Методами термогравиметрии, дифференциальной сканирующей калориметрии, рентгенофазового анализа и электронной микроскопии исследованы особенности окисления порошков аморфного бора, модифицированных пентоксидом ванадия. Модифицирование осуществляли путем смешения порошков с ванадийсодержащими гелями — гидрогелем состава V2O5 · nH2O и олеогелем состава V(OCH2)2 · n(HOCH2)2. Установлено, что добавление к порошку аморфного бора 2 % (мас.) V2O5 на 200 °C снижает температуру начала его интенсивного окисления и на 25 % повышает удельное тепловыделение в процессе взаимодействия при нагревании на воздухе со скоростью 10 °C /мин. Взаимодействие бора с пентоксидом ванадия рассмотрено в рамках модели бортермального процесса.

The oxidation of amorphous boron powders modified with vanadium pentoxide were studied by thermogravimetry, differential scanning calorimetry, X-ray phase analysis, and electron microscopy. The modification was carried out by mixing powders with vanadium-containing gels: V2O5 · nH2O hydrogel and V(OCH2)2 · n(HOCH2)2 oleogel. It was found that adding 2 wt.% V2O5 to the amorphous boron powder led to a decrease of 200 °C in the temperature at the onset of its intense oxidation and to a 25% increase in the specific heat release during interaction under heating in air at a rate of 10 °C/min. The reaction of boron with vanadium pentoxide is considered within the framework of a boron thermal process model.
СКОРОСТЬ ДЕТОНАЦИИ АЛЮМИНИЗИРОВАННОГО ЭМВВ В ПЛОСКОМ СЛОЕ
Authors: А.С. ЮНОШЕВ , А.В. ПЛАСТИНИН
Published: November 2024

Измерена скорость детонации эмульсионного взрывчатого вещества с добавлением алюминиевых порошков ПАП-2 и АСД-4 в зарядах разной толщины с разной начальной плотностью. Показано, что добавление алюминиевого порошка ПАП-2 уменьшает критическую толщину эмульсионного взрывчатого вещества. При больших толщинах заряда и плотности алюминизированного эмульсионного взрывчатого вещества более 1.0 г/см3 влияние порошков ПАП-2 и АСД-4 на скорость детонации эквивалентно. Замена алюминиевого порошка на порошок талька заметно ухудшает детонационные характеристики эмульсионного взрывчатого вещества. Результаты работы позволяют предположить, что алюминиевые порошки ПАП-2 и АСД-4 в составе эмульсионного взрывчатого вещества плотностью более 1.0 г/см3 полностью реагируют при детонации до поверхности Чепмена — Жуге.

Detonation velocity was measured for an emulsion explosive with the addition of PAP-2 and ASD-4 aluminum powders in charges of different thicknesses with different initial densities. Adding PAP-2 aluminum powder was found to reduce the critical thickness of the emulsion explosive. At large charge thicknesses and densities of the aluminized emulsion explosive of more 1.0 g/cm3, the effects of PAP-2 and ASD-4 powders on the detonation velocity are equivalent. Replacing aluminum powder with talc powder markedly deteriorates the detonation characteristics of the emulsion explosive. The results of the work suggest that PAP-2 and ASD-4 aluminum powders in the emulsion explosive with a density of more than 1.0 g/cm3 react completely during detonation to the Chapman–Jouguet surface.
ВЛИЯНИЕ МОДИФИЦИРУЮЩИХ ДОБАВОК НА ФАЗОВЫЙ ПЕРЕХОД АНАТАЗА В РУТИЛ
Authors: Э.П. ЛОКШИН , Т.А. СЕДНЕВА , М.Л. БЕЛИКОВ
Published: November 2024

Проанализированы результаты исследований по изменению при термообработке химического состава и структуры модифицированного гидроксида титана. Показано, что при нагревании во всех случаях сначала образуется анатаз, который при повышении температуры или/и продолжительности термообработки переходит в рутил. Температура начала перехода анатаз - рутил зависит от вида модифицирующего компонента. Переход происходит не скачком при определенной температуре, а постепенно в широком интервале температур, при этом одновременно могут существовать оба соединения. При постоянной температуре доля рутила возрастает с увеличением продолжительности термообработки. На основании проведенных исследований заключено, что в присутствии модифицирующих компонентов образцы диоксида титана представляют собой широкие классы нестехиометрических соединений с разной кристаллической структурой и переход анатаз - рутил не является полиморфным превращением I рода, а является следствием протекания различных химических процессов, включающих выделение анионных и/или катионных примесей в газовую или твердую фазу.

The results of studies on changes in the chemical composition and structure of doped titanium hydroxide during thermal treatment are analysed. It is shown that anatase is formed at first under heating in all cases, and with further increase in temperature or in the duration of thermal treatment it is transformed into rutile. The temperature of the start of anatase-rutile transition depends on the type of doping component. The transition proceeds not abruptly at a certain temperature but gradually over a wide temperature range, while both compounds can exist simultaneously. At a constant temperature, the proportion of rutile increases with an increase in the duration of thermal treatment. It is concluded on the basis of the conducted studies that the samples of titanium dioxide in the presence of doping components represent the broad classes of non-stoichiometric compounds with different crystal structures, and the transition of anatase to rutile is not a polymorphic transformation of the 1st kind but it is a consequence of various chemical processes involving the release of anionic and/or cationic impurities into the gas or solid phases
EVALUATION OF ANTIOXIDANT ACTIVITY OF 2H-CHROMENE DERIVATIVES THROUGH OPTIMIZED GREEN SYNTHESIS
Authors: S.A. PATEL , S.P. PATEL , H.V. VAGHANI , J.H. KUMBHANI
Published: November 2024

The increasing concern for environmental sustainability and the need for efficient and green chemical synthesis have driven the development of alternative methods for producing new compounds. In this study, we have synthesized a series of novel 2H-chromene derivatives using a one-pot multicomponent reaction under ultrasound sonication. The use of ultrasound sonication is a green and efficient synthetic method that utilizes sound waves to initiate chemical reactions. We optimized various reaction parameters, such as solvent, temperature, catalyst amount, and reaction time, to identify the best reaction conditions for the synthesis of the derivatives. The synthesized compounds were characterized using analytical techniques such as IR, mass, 1H and 13C NMR spectra, which confirmed the molecular structures of the derivatives. Furthermore, the antioxidant activities of the synthesized derivatives were evaluated and compared to those of ascorbic acid. The IC50 values of the derivatives were promising, indicating their potential as antioxidants. Overall, this study demonstrates the effectiveness of ultrasound sonication as a green and sustainable approach to the synthesis of novel compounds with potential biological activities. The use of one-pot multicomponent reactions also adds to the efficiency and simplicity of the synthesis method. These findings may have important implications for the development of new and sustainable chemical synthesis methods in the future.
СИНТЕЗ 1,1′-(2,3,5,6-ТЕТРАФТОР-1,4-ФЕНИЛЕН)ДИПРОПАН-1-ОНА
Authors: А.С. ВИНОГРАДОВ , С.Б. КАЛАШНИКОВ , В.Е. ПЛАТОНОВ , Т.В. МЕЖЕНКОВА
Published: November 2024

1-(Пентафторфенил)пропан-1-он реагирует с цинком в присутствии каталитических количеств SnCl2 при нагревании в диметилформамиде с образованием (2,3,5,6-тетрафтор-4-пропионилфенил)цинкхлорида и бис(2,3,5,6-тетрафтор-4-пропионилфенил)цинка. Из этих цинкорганических соединений и пропионилхлорида в присутствии CuI синтезирован 1,1′-(2,3,5,6-тетрафтор-1,4-фенилен)дипропан-1-он. Реакция цинкорганических соединений, полученных из 3-бром-1,2,4,5-тетрафторбензола, с пропионилхлоридом приводит к образованию 1-(2,3,5,6-тетрафторфенил)пропан-1-она.

1-(Pentafluorophenyl)propan-1-one reacts with zinc in the presence of catalytic amounts of SnCl2 under heating in dimethyl formamide to give (2,3,5,6-tetrafluoro-4-propionylphenyl)zinc chloride and bis(2,3,5,6-tetrafluoro-4-propionylphenyl)zinc. 1,1'-(2,3,5,6-Tetrafluoro-1,4-phenylene)dipropan-1-one was synthesized from these organozinc compounds and propionyl chloride in the presence of CuI. The reaction of organozinc compounds obtained from 3-bromo-1,2,4,5-tetrafluorobenzene leads to the formation of 1-(2,3,5,6-tetrafluorophenyl)propan-1-one
МОБИЛЬНОСТЬ ТРИАРИЛМЕТИЛЬНЫХ РАДИКАЛОВ В ВОДНО-ГЛИЦЕРИНОВЫХ И ВОДНО-ТРЕГАЛОЗНЫХ СРЕДАХ
Authors: А.Е. РАЙЗВИХ , К.А. ЛОМАНОВИЧ , О.Ю. РОГОЖНИКОВА , Д.В. ТРУХИН , В.М. ТОРМЫШЕВ , Е.Г. БАГРЯНСКАЯ
Published: November 2024

В последние годы триарилметильные радикалы широко применяются в качестве спиновых зондов и меток, поэтому исследование их свойств представляет большой интерес. С использованием методов стационарного и импульсного электронного парамагнитного резонанса (ЭПР) в широком температурном диапазоне изучены магнитно-резонансные свойства меченных изотопом 13С триарилметильных радикалов (FT (Finland trityl) и OX063) в растворах "вода - глицерин" и "вода - трегалоза". Измерены их магнитно-резонансные параметры, времена электронной спиновой релаксации и определены времена корреляции вращения при разных температурах. Показано, что в растворе трегалозы радикал 13С-FT образует агрегаты, а для радикала 13С-OX063 агрегатов не наблюдается.

In the recent years, triarylmethyl radicals are widely used as spin probes and tags, so the study of their properties is of great interest. In the present work, the magnetic resonance properties of triarylmethyl radicals (FT (Finland trityl) and OX063) labeled with 13C isotope in water-glycerol and water-trehalose solutions are studied using stationary and pulsed EPR within a wide temperature range. Their magnetic resonance parameters, electron spin relaxation times and rotation correlation times at different temperatures are measured. It is shown that 13С-FT radical forms aggregates in trehalose solution, while aggregates are not observed for 13С-OX063 radical.
КАЧЕСТВЕННЫЙ И КОЛИЧЕСТВЕННЫЙ АНАЛИЗ КОНДЕНСАТОВ, ПОЛУЧАЕМЫХ ПРИ СУШКЕ ДРЕВЕСИНЫ СОСНЫ ОБЫКНОВЕННОЙ
Authors: Е.П. РОМАНЕНКО , Т.В. ПУЧКОВА , А.В. ТКАЧЕВ
Published: November 2024

Конденсаты, получаемые при сушке древесины, представляют собой разбавленные водные растворы летучих веществ и по свойствам наиболее близки широко известным гидролатам. Анализ состава гидролатов часто проводится с использованием предварительной их экстракции органическими растворителями. Однако при этой процедуре могут теряться некоторые гидрофильные соединения, в результате чего результаты анализа не будут соответствовать нативному составу гидролата. В настоящей работе разработана модифицированная методика ГЖХ-анализа с предподготовкой образца, включающей экстракцию конденсата органическим растворителем, путем использования при анализе внутреннего стандарта гидрофобной природы. Разработанная методика опробована на конденсатах древесины сосны обыкновенной (Pinus sylvestris var. mongolica Litv.), но может применяться как к конденсатам, получающимся при сушке других древесных материалов и иного растительного материала, так и к гидролатам.

The condensates obtained during wood drying are dilute aqueous solutions of volatile substances and are the closest in their properties to widely known hydrolates. The analysis of the composition of hydrolates is often carried out using their preliminary extraction with organic solvents. However, some hydrophilic compounds may be lost during this procedure, so that analysis results might not correspond to the native composition of the hydrolate. In this work, we have developed a modified technique of GLC analysis with preliminary sample preparation, including the extraction of condensate with an organic solvent, by using an internal standard of hydrophobic nature in the analysis. The developed technique has been tested on hydrolates of ordinary pine wood ( Pinus sylvestris var. mongolica Litv.), but it can also be applied both to condensates obtained during drying of other wood materials and other plant material, and to hydrolates.
СИНТЕЗ ФТОРИРОВАННЫХ БЕНЗОТИАЗОЛОВ, ИССЛЕДОВАНИЕ НАПРАВЛЕНИЙ ИХ ЛИТИИРОВАНИЯ И ПОСЛЕДУЮЩЕГО ВЗАИМОДЕЙСТВИЯ С ДИМЕТИЛФОРМАМИДОМ
Authors: В.Е. РОМАНОВ , Е.В. ПАНТЕЛЕЕВА
Published: November 2024

Взаимодействием 4,6-дифтор-, 4-фтор- и 2-бром-4,6-дифторбензотиазола с BuLi или LiN[(CH3)3Si]2 в тетрагидрофуране с последующими обработками диметилформамидом и MeI установлены основные положения металлирования модельных моно- и дифторированных бензотиазолов и охарактеризована реакционная способность образующихся Li-производных в отношении формилирования и метилирования.

The interaction of 4,6-difluoro-, 4-fluoro-, and 2-bromo-4,6-difluorobenzothiazole with BuLi or LiN[(CH3)3Si]2 in tetrahydrofurane, followed by the treatment with dimethylformamide and MeI, revealed the main metalation sites in these model mono- and difluorinated benzothiazoles. The reactivity of the resulting Li-derivatives with respect to formylation and methylation was also characterized.
СИНТЕЗ И ОЦЕНКА ЦИТОТОКСИЧНОСТИ ФУРАНОЛАБДАНОИДОВ, СОДЕРЖАЩИХ 3-АМИНОПРОПАНОИЛЬНЫЙ ЗАМЕСТИТЕЛЬ В ФУРАНОВОМ ЦИКЛЕ
Authors: Ю.В. ХАРИТОНОВ , Д.А. ПЕТРОВА , Э.Э. ШУЛЬЦ , М.А. ПОКРОВСКИЙ , А.Г. ПОКРОВСКИЙ
Published: November 2024

15-Ацетил- и 16-ацетилфуранолабданоиды получены ацетилированием метилового эфира ламбертиановой кислоты уксусным ангидридом в присутствии Mg(ClO4)2 и использованы как ключевые соединения для синтеза 15- или 16-(3-аминопропаноил)метилламбертианатов. Предложенный подход включал силилирование 15-ацетил- или 16-ацетилметилламбертианата и реакцию Манниха образующегося силилового эфира енола с N,N-дизамещенными метилениминиевыми солями. Синтезированные соединения обладали цитотоксичностью на линиях опухолевых клеток CCRF CEM, MCF7 и PC-3 (МТТ-тест). Соединения, содержащие 3-морфолинопропаноильный или 3-пирролидинопропаноильный заместитель в положении С-16 метилламбертианата, селективно ингибировали рост клеток Т-клеточного лейкоза человека (GI50 составило 5.8-6.1 мкM) и проявляли на порядок большую цитотоксичность, чем исходное соединение - ламбертиановая кислота.

15-Acetyl- and 16-acetylfuranolabdanoids were synthesised by the acetylation of the methyl ester of lambertianic acid with acetic anhydride in the presence of Mg(ClO4)2 and used as starting compounds for the preparation of 15- or 16-(3-aminopropanoyl)methyllambertianates. The proposed approach involved silylation of 15-acetyl- or 16-acetylmethyllambertianate and the Mannich reaction of the resulting enol silyl ester with N,N-disubstituted methyleneiminium salts. The synthesized compounds possessed cytotoxicity on tumour cell lines CCRF CEM, MCF7 and PC-3 (MTT test). The compounds containing a 3-morpholinopropanoyl or 3-pyrrolidinopropanoyl substituent at the C-16 position of methyl lambertianate selectively inhibited the growth of human T-cell leukemia cells (GI50 was 5.8-6.1 μM) and exhibited cytotoxicity an order of magnitude higher than the parent compound lambertianic acid.
СИНТЕЗ 2,4-ДИАРИЛЗАМЕЩЕННЫХ 3H-1,5-БЕНЗОДИАЗЕПИНОВ ПОСЛЕДОВАТЕЛЬНОЙ ТРЕХКОМПОНЕНТНОЙ РЕАКЦИЕЙ 5-(ЭТИНИЛ)МЕТИЛАНТРАНИЛАТА, БЕНЗОИЛХЛОРИДОВ И О-ФЕНИЛЕНДИАМИНА
Authors: К.П. ЧЕРЕМНЫХ , В.А. САВЕЛЬЕВ , А.Б. СКОРОВА , Э.Э. ШУЛЬЦ
Published: November 2024

Предложено использование доступной синтетической платформы 5-этинил-N-(ацетил)антраниловой кислоты в синтезе химической библиотеки 2,4-диарил-3Н-1,5-бензодиазепинов. Ключевая стадия синтеза включала реакцию генерированного in situ метил 2-ацетиламино-5-[3-(4-арил)пропиолил]бензоата с о-фенилендиамином. Найденные условия были использованы для синтеза химической библиотеки 3Н-1,5-бензодиазепинов, содержащих фрагмент метилового эфира антраниловой кислоты в положении С-2. Также приведены физико-химические характеристики промежуточно образующихся α,β-алкинилкетонов.

The use of the available synthetic platform of 5-ethynyl-N-(acetyl)anthranilic acid in the synthesis of a chemical library of 2,4-diaryl-3H-1,5-benzodiazepines is proposed. The key step of the synthesis included the reaction of in situ generated methyl 2-acetylamino-5-[3-(4-aryl)propiolyl]benzoate with o-phenylenediamine. The selected conditions were used for the synthesis of a chemical library of 3H-1,5-benzodiazepines containing an anthranilic acid methyl ester fragment in the C-2 position. The physicochemical characteristics of intermediately formed α,β-alkynyl ketones are also described.