bluuebunny/crossref_metadata_2025 huggingface dataset:
The state of ocular arterial blood flow in active retinopathy of prematurity
Authors: Trifanenkova I. G. , Tereshchenko A. V. , Erokhina E. V.
Published: December 2022

Purpose: to study the state of blood flow in the ocular arteries of patients with various forms, stages and course types of active retinopathy of prematurity (ROP). Material and methods. Colour duplex scanning was performed by colour Doppler mapping and pulsed Doppler sonography for 55 premature babies (55 eyes) with active ROP and 8 premature babies (8 eyes) without ROP signs. The children’s gestation age was 25 to 32 weeks, and the body weight at birth was 680 to1760 g. Blood flow was examined in the ophthalmic artery (OA), the central retinal artery (CRA) and the medial and lateral posterior short ciliary arteries (PSCA). Results. The ophthalmic artery revealed no significant differences between the children with ROP and without ROP, except for a significant increase in the peak systolic velocity (Vsyst) in an unfavorable course of stage III of ROP. The development of aggressive posterior ROP is accompanied by a statistically insignificant decrease in blood flow velocity of OA. Hemodynamic parameters of CRA indicate an increase in peripheral vascular resistance in children with an unfavorable course of ROP. A significant increase of Vsyst in the posterior short ciliary arteries was revealed in children with an unfavorable course of stages I–III of ROP and Vsyst, and Vdiast (diastolic blood flow velocity) in children with aggressive posterior ROP as compared with children without ROP. A pronounced impact of the ROP course (favorable or unfavorable) on the Vsyst, Vdiast, and PI indicators in the posterior short ciliary arteries was revealed. The most informative hemodynamic parameters in predicting the course of active ROP are Vsyst and Vdiast values in the ophthalmic artery and Vsyst in the posterior short ciliary arteries. The least informative were the hemodynamic parameters of the central retinal artery. Conclusion. The assessment of hemodynamic changes in eye arteries may be used as an additional diagnostic criterion in the early diagnosis of ROP.
Virtual Communication as the Main Format of Social Communication of Young People
Authors: Irkova Anna
Published: December 2022

The features of the communicative behavior of young people in the network discursive space are considered. The purpose of the study is to assess the characteristic linguistic features of young people in social networks. The research material was the data of a questionnaire aimed at identifying the motives and goals of young people in network communication. About 150 people (students of different faculties and courses) were interviewed. An anonymous survey was conducted by 100 schoolchildren (the age of teenagers ranged from 12 to 17 years). On the youth platforms of the Runet, data from Internet discussions and comments from communication participants are collected. The results of the study showed that the reconstruction of the portrait of the linguistic personality of a young user of social networks is associated with the following factors. Firstly, a special digital linguistic personality is being formed in the Internet space. It acts as a synthesis of a real linguistic personality with its constructed image. It has its own language features. They are revealed in a new vocabulary, modified by the youth itself, slang. A modern student in the context of social networks has a synthesis of two spheres – educational and communicative. The vocabulary of a modern teenager is reduced to simple colloquial expressions, often profanity (obscene words), jargon. The speech of teenagers has become very everyday and real. Most words of modern slang have several features: these are mostly abbreviated and borrowed words. The dynamism of the modern world is reflected in the very frequent use of nouns with event meaning and verbs. Secondly, against this background, the text is increasingly accompanied by illustrations, stickers, emoticons and many others. The importance of social networks for the self-expression of young people is emphasized.
La Peña de Santana (Segovia, España): cazadores-recolectores magdalenienses en el interior de la península ibérica
Authors: Álvarez-Alonso David , De Andrés-Herrero María , Díez Herrero Andrés
Published: December 2022

La investigación del Paleolítico superior en el interior peninsular se ha ido intensificando en los últimos años, aunque es un proceso lento. A los yacimientos ya conocidos, como Estebanvela, Buendía o Verdelpino se han ido uniendo nuevos descubrimientos, contribuyendo a apartar definitivamente el panorama de un aparente despoblamiento, algo que ya no es posible mantener al menos a partir del UMG. En este trabajo presentamos el reciente hallazgo y excavación de un yacimiento magdaleniense en Segovia, en el pie de monte sur del Sistema Central. Se trata de un hallazgo de relevancia, que contribuye a plantear nuevas vías de investigación sobre el poblamiento a finales del Paleolítico superior en las zonas interiores de la península, y sus relaciones con el Cantábrico y la zona levantina.
Introducing Hydroinformatics
Authors: Abbott Michael B.
Published: December 2022

Hydroinformatics is the name of a new way of applying knowledge as this knowledge is utilised in the worlds of the waters. This new way of applying knowledge, which is developing generally within our present-day societies, is concerned with ways to access and employ electronically encapsulated information, which itself becomes knowledge just to the extent that it is genuinely accessed and authentically employed. The knowledge of how to apply knowledge in the new way is thus itself a certain kind of ‘metaknowledge’.
Forchheimer and Schoklitsch: A Postmodern Retrospection
Authors: Abbott Michael B.
Published: December 2022

This truncated archaeology of the meaning and understanding of the hydraulics of Forchheimer and Schoklitsch is used to bring out the changes occurring in such a technology as it passes from the modern to the postmodern condition of society.
Towards a hydroinformatics praxis in the service of social justice
Authors: Abbott M. B. , Vojinovic Z.
Published: December 2022

This paper introduces a new role for hydroinformatics in its sociotechnical environment. It introduces a novel and modern approach for dealing with flooding and other such destructive phenomena which have been increasing ever more rapidly throughout the world. By far the greatest toll from floods and flood-related disasters, however, is in the so-called “developing” world where the resources for dealing with such problems are either inadequate or non-existent, even as these are often subject to the interventions of corrupt behaviour and practices and their related dubious legal systems. The necessity of promoting the nature of the force that is required to overcome these negativities are identified as those provided by active stakeholder participation and this paper indicates how this force can be informed and motivated largely through projecting ultra-realistic dynamic and coloured illustrations within a collective social environment.
Caracteristicas epidemiológicas, clínicas histopatológicas y quirúrgicas en adolescentes con tumoración de ovario de un hospital nacional
Authors: Aquino Cabrera Noemí Flora
Published: December 2022

Objetivo: Determinar las características epidemiológicas, clínicas, histopatológicas y quirúrgicas en adolescentes con tumoración de ovario de un Hospital Nacional. Materiales y métodos: El estudio es de tipo descriptivo, retrospectivo y transversal. Se contó con una población de 63 pacientes. La técnica de recolección de datos se dio a través de fichas previamente elaboradas en donde se plasmaban los datos de las historias clínicas. Resultados: En cuanto a las características epidemiológicas se obtuvo que la edad de mayor frecuencia fue entre 11 a 18 años 85% (n=63), dentro de las características clínicas, la sintomatología más frecuente fue el dolor abdomino pélvico 96% (n=63), además dentro de las características histopatológicas, el tumor más frecuente fue el tipo Endometriosico 47% (n=63) y la cirugía que se realizó con mayor frecuencia fue la laparotomía 61% (n=63). Conclusiones: Los tumores de ovario en niñas y adolescentes tienen una frecuencia de 1,5% de acuerdo a su tipo de presentación, su forma de presentación aun es atípica, la gran mayoría de tumores son de tipo benigno, la cirugía que mayormente se realizo fue la laparotomía abierta.
Riesgo cardiovascular y perímetro abdominal en trabajadores con jornada laboral atípica a gran altura en el Perú
Authors: Huamani Morales Katherin Lizet , Mendoza Arana Pedro Jesús , Segovia Hermoza Milner
Published: December 2022

Introducción. Existen elementos adicionales relacionados al riesgo cardiovascular especialmente en la población trabajadora, tales como tipo de jornada de trabajo y el perímetro abdominal. Objetivo. Determinar la relación entre el riesgo cardiovascular y perímetro abdominal en trabajadores con jornada laboral atípica que trabajan a gran altura en el Perú. Materiales y Métodos. Estudio de enfoque cuantitativo, de diseño metodológico descriptivo transversal. La población estuvo conformada por 151 exámenes médico-ocupacionales de trabajadores de una institución pública de la ciudad del Cusco. La técnica fue la recolección de datos a partir de la revisión de los exámenes médico-ocupacionales y el instrumento fue diseñado a partir de la escala ACC/AHA ASCVD RISK, además se incluyó a este instrumento datos clínicos y sociodemográficos, que fue validado por comité de expertos. Resultados: El 72,2% de los trabajadores presentaron riesgo cardiovascular bajo y el 27,8% riesgo cardiovascular Elevado, además la relación que existe entre el perímetro abdominal y el riesgo cardiovascular es estadísticamente significativa (p=0.019). Conclusiones: Existe relación significativa entre el nivel de riesgo cardiovascular y el perímetro abdominal en los trabajadores con jornada laboral atípica que trabajan a gran altura en el Perú.
Fidelización en los clientes de la tienda Platanitos, La Victoria – 2022
Authors: Seminario Unzueta Randall Jesús , Pérez Flores Liz Marita , Castro Guzmán Enrique
Published: December 2022

Objetivo: Determinar la fidelización en los clientes de la tienda Platanitos – La Victoria, 2022. Materiales y Métodos: Investigación cuantitativa, tipo aplicada, diseño no experimental, correlacional, de corte trasversal, nivel descriptivo, con una población de 204 clientes que visitan la tienda Platanitos. La técnica de recolección de datos es la encuesta, el instrumento es el cuestionario, comprendido por 18 ítems para la variable fidelización agrupada en 3 dimensiones y 3 indicadores en cada dimensión. Resultados: Del total de los encuestados de la tienda Platanitos, se puede observar que el 47,5% indica que la fidelización está en nivel muy alto; asimismo, el 30% indica que la fidelización está en nivel alto, el 16% dice que la fidelización es regular; por otro lado, el 4,4% afirma que la fidelización se encuentra en nivel bajo y el 0,5% dice que está en nivel muy bajo. Conclusiones: Se concluye que los productos ofrecidos tienen aceptación de nivel regular, los clientes consideran que se brinda una buena calidad en su servicio, tienen una experiencia regular y consideran que la comunicación de la marca con sus clientes es regular; por lo tanto, se debería mejorar.
Engineered Bacteria: General Overview as Therapeutic Agent and a Novel
Drug Delivery System
Authors: Patil Prashant L. , Gharat Shivani K. , Jadhav Kisan R. , Kadam Vilasrao J.
Published: December 2022

Bacterial engineering modifies bacteria's genomic sequence using genetic engineering
tools. These engineered bacteria can produce modified proteins, peptides, nucleic acids, and other
biomolecules that can be used to treat various medical conditions. Engineered bacteria can target
diseased tissues or organs, detect specific biomarkers in the diseased environment, and even induce
specific conditions. Furthermore, a meticulously designed intracellular metabolic pathway can activate
or inhibit the expression of related genes, synthesise biologically active therapeutic molecules,
and precisely deliver drug payloads to diseased tissues or organs. Lactococcus (L. lactis), Salmonella
(S. typhi), and E. coli (E. coli Nissle) are the most studied engineered microorganisms used as
drug carriers. These have been used in vaccines to treat multifactorial diseases such as cancer, autoimmune
diseases, metabolic diseases, and inflammatory conditions. Other promising strains include
Bifidobacterium animalis, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus
lugdunensis, and Clostridium sporogenes. Despite the low reported risk, toxic effects associated
with bacterial cells, limiting their efficacy and rapid clearance due to immune responses stimulated
by high bacterial concentrations, remain major drawbacks. As a result, a better and more effective
method of drug delivery must be developed by combining bacterial-based therapies with other
available treatments, and more research in this area is also needed.
A Scoping New Revolution for Tinnitus Management: A Neuromonics
Narrative Review
Authors: Gupta Jitendra , Gupta Reena
Published: December 2022

With a prevalence ranging from 16-21%, tinnitus is an irking neurological disorder, manifesting
as the perception of a roar of cacophony without an external acoustic stimulus. Although
tinnitus is a non-life-threatening symptom, tinnitus's negative repercussions, such as personality disturbances
and social withdrawal, are daunting concerns despite a gamut of conventional and emerging
treatment options. Tinnitus management is still a critical challenge that provides opportunities
for clinicians, ENT (Ear/eye, nose and throat) physicians, and other specialists such as audiologists,
psychiatrists, and psychologists. Among the new treatment modalities, Neuromonics tinnitus
treatment (NTT) draws special attention in tinnitus management due to its mounting success rate.
Nonetheless, unlike in developed countries like Australia, the United States, and the United Kingdom,
the scanty awareness of NTT among Indian ENT specialists is a titanic setback for care
providers. Because of this backdrop, this review emphasized the current perspectives on tinnitus
management and the underlying principles and clinical efficacy of NTT. The challenges for tinnitus
management can be met and reduced by suppressing tinnitus through motivation, counseling,
cochlear implant, and psychotherapy.
Neuroprotective Role of Quercetin against Alpha-Synuclein-Associated
Hallmarks in Parkinson’s Disease
Authors: Das Sabya Sachi , Jha Niraj Kumar , Jha Saurabh Kumar , Verma Priya Ranjan Prasad , Ashraf Ghulam Md , Singh Sandeep Kumar
Published: December 2022

Quercetin, a natural antioxidant, exhibits potential neuroprotective effects by efficiently
downregulating α-synuclein protein aggregation and associated neurological hallmarks, responsible for
the progression of Parkinson’s Disease.
Deep Learning Models for Coronary Atherosclerosis Detection in Coronary CT
Angiography
Authors: Laidi Amel , Ammar Mohammed , Daho Mostafa El Habib , Mahmoudi Said
Published: December 2022

Background:

Patients with atherosclerosis have a rather high risk of showing complications,
if not diagnosed quickly and efficiently.

Objective:

In this paper we aim to test and compare different pre-trained deep learning models, to find
the best model for atherosclerosis detection in coronary CT angiography.

Methods:

We experimented with different pre-trained deep learning models and fine-tuned each model
to achieve the best classification accuracy. We then used the Haar wavelet decomposition to improve
the model’s sensitivity.

Results:

We found that the Resnet101 architecture had the best performance with an accuracy of
95.2%, 60.8% sensitivity, and 90.48% PPV. Compared to the state of the art which uses a 3D CNN and
achieved 90.9% accuracy, 68.9% Sensitivity and 58.8% PPV, sensitivity was quite low. To improve
the sensitivity, we chose to use the Haar wavelet decomposition and trained the CNN model with the
module of the three details: Low_High, High_Low, and High_High. The best sensitivity reached 80%
with the CNN_KNN classifier.

Conclusions:

It is possible to perform atherosclerosis detection straight from CCTA images using a
pretrained Resnet101, which has good accuracy and PPV. The low sensitivity can be improved using
Haar wavelet decomposition and CNN-KNN classifier.
Preconcentration of Phenylalanine in Cheese and Yoghurt Using Deep
Eutectic Solvent and Determination by HPLC Technique
Authors: Shokrollahi Ardeshir , Karami Forough
Published: December 2022

Background:

In the current research, a green, fast and cheap extraction method based on deep
eutectic solvent was developed for the preconcentration of phenylalanine. Then, high performance liquid
chromatography (HPLC) as a sensitive and accurate technique was used to determine amounts of preconcentrated
phenylalanine.

Objective:

The combination of the HPLC technique and extraction procedure using deep eutectic solvent
makes it possible to find a good procedure for the preconcentration of phenylalanine in different media
with acceptable precision and accuracy.

Methods:

Decanoic acid and tetrabuthylammonium bromide were used as the components of the green
solvent. Then, the synthesized green solvent was used for the preconcentration of phenylalanine. HPLC
equipped with a UV-VIS detector, a C18 column, a mixture of sodium dihydrogen phosphate 2-hydrate
(20 mM, pH 6.60)-ACN (70-30%) as the mobile phase, and the wavelength of 245 nm were selected as
the best separation.

Results:

The chief characteristic of deep eutectic solvent was identified using Fourier transform infrared
spectroscopy. Central composite design to evaluate the effects of preconcentration parameters showed
that the pH value of 6.31, salt concentration of 0.272 M, DES volume of 226 μL, and stirrer time of 5.60
min were suggested as the best conditions of separation. Total analysis time was 5.50 min.

Conclusion:

Validation of designed analysis exposed good linearity (0.015-1.50 μg/mL), suitable sensitivity,
excellent preconcentration (32.50) and enrichment (21.15) factors, acceptable relative standard
deviation (3.07%), and low amounts of detection limit (0.015 μg/mL). Finally, the designed method was
effectively used for the determination of phenylalanine in cheese and yoghurt with relative recoveries of
113.33 to 125.00% and 94.00 to 100.00%, respectively.
Carbon Dots Hybrid Nanostructure-based Electrochemical Sensors:
Applications in Determining Different Species in a Real Sample
Authors: Ferreira Joao A. , Name Luccas L. , Lieb Laura C. , Tiba Daniel Y. , da Silva Mariana M. , Oliveira Aprys C. , Canevari Thiago C.
Published: December 2022

This overview describes the synthesis, characterization, and application of different
carbon dots hybrid nanostructures obtained by chemical interaction between nanomaterials or
nanomaterials bonded to another material, i.e. silicon (SiO2/Carbon dots-N), reduced graphene
oxide (rGO/Carbon dots), multiwalled carbon nanotubes (MWCNTs/Carbon dots), nano magnetite
(Carbon dots/Fe3O4), reduced graphene oxide and gold nanoparticles (rGO/Carbon
dots/AuNPs), copper oxide (CuO/Carbon dots), and Carbon dots/Metallic NPs that were employed
in the development of electrochemical (bio)sensors. The formation of different carbon
dots hybrid nanostructures has been characterized by X-ray diffraction (XRD), Raman and ultraviolet-
visible spectroscopy, atomic force microscopy (AFM), high-resolution transmission electron
microscopy (HR-TEM), and electrochemical techniques. These carbon dots hybrid
nanostructures have been used to modify the surface of glassy carbon and screen-printed electrodes
and to determine various analytes, i.e., dopamine, uric acid, paracetamol, ephynefrin,
dihydroxybenzenes, pesticides, endocrine disruptors, NADH, and other substances in real samples.
Comparison of the Efficacy of Honey and Clotrimazole Cream in the Vulvovaginal
Candidiasis Treatment: A Systematic Review and Metaanalysis
Authors: Mirghafourvand Mojgan , Mollazadeh-Narestan Zahra , Yavarikia Parisa , Mashayekh-Amiri Sepideh , Gholizadeh Pourya
Published: December 2022

Background:

Vulvovaginal candidiasis (VVC) is a common fungal infection of the vaginal area affecting 75% of women at least once in their lifetime. However, there is no clear evidence helping to choose the most effective treatment method to improve the symptoms of VVC.

Objective:

The objective of this study was to compare the effect of using honey with clotrimazole on the treatment of symptoms of VVC.

Methods:

All databases in English (Embase, MEDLINE, ProQuest, Google Scholar, Scopus, Cochrane Library, and Web of Science) and Persian (Irandoc, SID, and Magiran) were searched without time limitation. Evaluation of studies in terms of bias was performed using the Cochrane handbook. Four clinical trials were included in the present systematic review; however, only three of them were included in the meta-analysis.

Results:

The results of the meta-analysis demonstrated that the rate of positive culture after treatment (RR: 2.35; 95%CI: 1.45 to 3.82) was significantly higher in the honey group than in the clotrimazole one. The frequency of itching after treatment (RR: 0.25, 95%CI: 0.12 to 0.49) was significantly lower in the honey-receiving group than in the clotrimazole one. However, there was no statistically significant difference in the incidence of other symptoms of VVC, including vaginal discharge (RR: 0.26, 95%CI: 0.02 to 2.75), vaginal burning (RR: 0.35, 95%CI: 0.03 to 3.80) and dyspareunia (RR: 0.64, 95%CI: 0.27 to 1.50) between groups.

Conclusion:

Due to the low quality of the studies, more clinical trial studies with stronger designs in this field are needed to clearly identify the therapeutic effects of honey on improving the symptoms of VVC.
A 16 Epithelia-mesenchymal Transition Associated LncRNAs Signature to Optimize Prognosis Predication of Stomach Adenocarcinoma
Authors: Yan Yanhua , He Xinru , Chen Yanfen , Huang Yuancheng , Jiang Xiaotao , Zheng Junhui , Chen Xu
Published: December 2022

Aim:

The study aimed to identify critical long non-coding RNAs (lncRNAs) and constructed a prognostic signature to optimize prognosis predication of patients with Stomach Adenocarcinoma (STAD).

Background:

STAD is a common malignant tumor with a high metastasis rate and low survival rate. LncRNAs participate in the regulation process of epithelial-mesenchymal transition (EMT) and the development of STAD.

Methods:

RNAseq data were obtained from TCGA-STAD, while 200 EMT-associated genes (EAGs) from the ‘HALLMARK_EPITHELIAL_MESENCHYMA-L _TRANSITION’ gene set. Differentially expressed EAGs and EMT-associated lncRNAs (EALs) were identified. Moreover, Lasso-Cox regression analysis was used to construct a signature of differentially expressed EALs, and univariate and multivariate analyses, Kaplan-Meier analysis, receiver operating characteristic curve (ROC) analysis, and nomogram were conducted to predict its prognostic value. An enrichment functional analysis was performed. Quantitative Real-Time PCR (qRT-PCR) was used to determine lncRNAs expressions in cell lines.

Results:

A total of 52 differentially expressed EAGs and 320 EALs were identified in this study. Meanwhile, 16 EALs were used to construct the signature, and further analysis indicated that it had a high prognostic value for STAD patients. Enrichment functional analysis revealed the signature was correlated to tumor immunity in STAD. Moreover, three novel EALs expressions were confirmed in cell lines.

Conclusion:

A novel survival signature was established to predict and evaluate the prognosis of STAD patients.
Outcomes of Paediatric Cataract Surgery in Southern Jordan
Authors: Al-Zubi Khalid , Sarayrah Fawaz , Khasawneh Mahmoud
Published: December 2022

Background:

Congenital cataract is the leading global cause of preventable childhood blindness, and the onset of infantile and congenital cataracts is rare. Managing congenital cataracts is still challenging due to associated complications.

Objective:

This study aimed to assess the outcomes of congenital cataract surgery with intraocular lens implantation in southern Jordan.

Methods:

A retrospective case series included 20 children with congenital cataracts who underwent lensectomy, aged between 1 to 5 years, recruited using a purposive sampling technique. The mean age was 2.9 years ± 1.4. Intraocular pressure was measured preoperatively at baseline and then every three months, followed up postoperatively until one year. Schiotz tonometer is used to measure intraocular pressure.

Results:

The distribution of IOP and change in IOP values at baseline and post-operative follow-ups showed statistically significantly higher IOP values at three months of follow-up (P=0.03) and the last follow-up visit at 12 months (P=0.001). The results showed a statistically significant increase from baseline in the IOP of the unilateral cataract eye compared to its normal fellow eye (P=0.028). The post-operative evaluation showed that 14 patients demonstrated twenty-seven post-operative complications. Four eyes (14.2%) with posterior synechiae, 2 (7.1%) with anterior synechiae, 3 (10.7%) with decentration of IOL, 8 (28.6%) with pigment on IOL, 3 (10.7%) with transient corneal oedema and 7 (25%) developed post-operative glaucoma.

Conclusion:

We concluded that post-operative follow-up of one year in pediatric patients treated with congenital cataract surgery showed a significant increase in intraocular pressure.
DISCRETE-EVENT SIMULATION MODELLING OF SEA COAL TERMINAL WAREHOUSE USING ANYLOGIC
Authors: Mazurenko O. I. , Rusinov I. A.
Published: December 2022

The issues of simulation modeling of complex transport nodes and systems are considered in the paper. It has been determined that warehouses in seaports act as buffers and smooth out the resulting difference in incoming and outgoing cargo traffic between land and sea transport. When designing offshore coal terminals, choosing the size, layout and equipment of a warehouse is one of the cornerstones. The basic principles for the placement of coal piles, depending on the size and capacity of an open warehouse, the size of ship lots and the average shelf life are provided in the paper. One of the main indicators that determine the correctness of choosing the size and layout of an open warehouse is the coefficient of utilization of the warehouse capacity. Formulas for its calculation are given. The principles of stacking coal in piles are further defined in the paper. There are four main laying methods - conical, chevron, layering and windowed. Next, the dependence of the coal storage density on the mass of the stack and the utilization rate of the warehouse on the average storage time of the cargo is determined. It is concluded that it is possible to fully assess the impact of stochastic events occurring in the terminal warehouse only with the use of simulation modeling. Further, it is determined that mixing and homogenization operations can be carried out in open warehouses. The differences and principles of these processes are given. Approaches to the selection of warehouse equipment and cyclical machines are identified, the advantages and disadvantages of the various types of warehouse machines are indicated. Definitions of technical and operational performance of machines are given. The Anylogic environment is chosen for modeling. Using environment elements, a digital copy of the coal terminal warehouse, serving the material flow - bulk cargoes, is created. Further, a detailed explanation of the principles and approach to creating a digital model is given, the internal and external links of the elements are clarified. In conclusion, information about the options for setting up and managing the model, and brief information about the results obtained are given.
CURRENT STATUS AND PERSPECTIVE FOR THE DEVELOPMENT OF SHIPS AND PORT TERMINALS FOR CARBON DIOXIDE (CO2)
Authors: Kuptsov N. V.
Published: December 2022

The current achievements and future prospects in international scientific and project activities in the field of sea transportation of carbon dioxide (CO2) for further application in projects in the Russian Federation are analyzed in the paper. The theme is relatively new and actual - the port transshipment and transportation of this new gaseous cargo has been considered by the authors since the early 2010s, the first projects will be implemented by the mid-2020s. CCS (carbon capture and storage) is capture of CO2 from industrial processes, transportation and storage in underground geological structures; it is one of the key large-scale technologies for reducing CO2 emissions at industrial facilities. This causes a growing interest in the development of CO2 maritime transport, which is confirmed by the fact that in the current decade in Europe more than 5 large-tonnage CO2 maritime hubs have been announced for implementation. Maritime transport is a promising type for the delivery of carbon dioxide from territorially remote emitters (more than 1 km) to CO2 injection geological fields, what is confirmedby the scientific researches and feasibility studies. The analysis of the most cited and authoritative scientific sources performed in the paper has shown that significant progress has been made in certain technological areas: the reliability of the technological chain has been confirmed, the transport characteristics of CO2 have been determined, and a conclusion about the advisability of transporting CO2 in ships under medium (15-20 bar, operated by a small-tonnage fleet of food-quality CO2 and vessels for the Norwegian Longship project) or low pressure(up to 10 bar, the greatest prospects are in cost reduction and increase of cargo capacity) has been drawn. At port terminals, operations for CO2 storage in isothermal tanks and loading-unloading through marine loading arms of liquid cryogenic cargoes will be confirmed by 2024 with the construction of the first marine CO2 hub in Norway(Northern Lights). In the study described in the paper, for the first time on the Russian language, the general functional and technological logic of the CO2 maritime transport chain is formed and the best promising available technologies are identified. Eventually based on the results of the analysis, a groundwork for further research and applied work, which has high potential due to the growing demand of the state and industrial enterprises to reduce the carbon footprint, is created.
IMPACT OF SURFACE CURRENTS ON VARIATIONS IN LEVELS AND MEAN ICE THICKNESS OF THE ARCTIC SEAS
Authors: Kholoptsev Aleksandr V. , Podporin Sergey A.
Published: December 2022

The impact of surface currents on variations in levels and mean ice thickness of the Arctic seas is considered in the paper. On the example of sites of the Greenland Sea and the Baffin Sea water areas, the hypothesis of a significant correlation between changes in the topography of the water surface and the average ice thickness in areas under the influence of warm and cold surface currents is tested. Similar, although less expressed, patterns of currents also take place in other Arctic seas, including the Barents and Kara seas, which are characterized by intensive navigation in the waters of the Northern Sea Route. The results of the GLORYS12v1 reanalysis, available for every day of a period of more than 10 years with a coordinate step of 5 arc minutes, are used as initial data on the water surface level and mean ice thickness in the study area. For each node of the coordinate grid for the months from November to March, time series of data on the average monthly values of the indicated characteristics are formed. It has been established that at the sites through which warm currents pass, carrying more saline water, such a correlation exists in most areas and it is negative. At the sites through which cold currents pass, carrying water with lower salinity, the correlation of the same processes can be significant and positive. It is assumed that the identified patterns are also manifested in other areas of the Arctic seas with similar currents systems, including those located along the Northern Sea Route and characterized by active navigation. The expediency of taking into account sea level changes in such areas in the course of medium- and long-term forecasting of the average ice thickness in them in order to plan year-round navigation, including during the most difficult winter-spring navigation period, is noted.
THE INFLUENCE OF LOCAL RESIDUAL DEFORMATIONS ON THE SHIPS HULLS RELIABILITY
Authors: Baryshnikov Sergei O. , Krasiuk Alla B. , Chistov Valentin B.
Published: December 2022

The changes in the bearing capacity of the hull sheets and beams of the ship’s set under the action of compressive and tensile forces are studied in the paper. The inf luence of local residual deformations on the permissible wear of the deformed element, which allows assessing its reliability, is established. Since the longitudinal forces (compressive and tensile) are significant only for the deck or bottom in the middle part of the hull, the effect of local residual deformations on the bearing capacity of sheets and beams of the longitudinal set is estimated only for these elements. It is assumed that the retained local residual deformations of the housing elements do not change with the time of ship operation. Corrections for permissible wear in the cross-section equal to a decrease in the average thickness of the sheets in the cross-section are calculated (for a section of the body equal to the length of the sheet, from joint to joint). The wear rate of all cross-section sheets is assumed to be the same, and the probability of its occurrence corresponds to the law of normal distribution with the characteristics specified in the Rules of the Russian River Register established for a given group of elements. According to the assumptions made above, it is possible to calculate the probability of failure in the cross-section of a group of elements with local residual deformations depending on the number of years of the vessel operation. The probability of failures in a given group of elements is estimated by the multiplication of the failures probability in several sections after a given number of years of operation. The probability of failures in the hull of the vessel is calculated as the multiplication of the failures probabilities in all groups of elements. Formulas for calculating the loss of the bearing area of the sheathing plates and beams of the longitudinal set due to the local residual deformations have been obtained. The loss of the working area of the sheets and longitudinal beams is represented as additional wear of the sheets. After dividing the mentioned loss of the cross-section area by the cross-section width, the value of the permissible reduction in the residual thickness of the sheets, weighted average for the section under consideration, is obtained.
ENVIRONMENTAL SAFETY OF POWER PLANTS: DUAL-FUEL AND GAS ENGINES
Authors: Zhivljuk Grigorij E. , Petrov Aleksandr P.
Published: December 2022

The subject of this study is internal combustion engines capable of using gaseous fuels-gas and dual-fuel engines. The main technologies of using natural gas in piston engines from the standpoint of ensuring the highest energy efficiency and environmental safety are considered in the paper. It is noted that the use of natural gas as a fuel, regardless of the technology, reduces carbon dioxide emissions from combustion products by 28 % compared to liquid fuels. All known designs of gas and dual-fuel engines fundamentally implement two technologies, namely, the use of homogeneous or heterogeneous gas-air mixtures. The most common is the technology of homogeneous mixtures, which provides high fuel efficiency and the highest environmental safety indicators. This technology provides for the supply of low-pressure gas to the intake ducts of the engine through automatic gas valves. There are practically no sulfur oxides, solid particles in the exhaust gases of the engine, and the emission of nitrogen oxides can be provided at the level of the requirements of the Tier III standard. At the same time, the main disadvantage of the homogeneous mixture technology is the potential penetration of natural gas with a high level of greenhouse effect (which is up to 28 times higher than the effect of carbon-acid gas) into the exhaust tract of the engine - “methane slippage”. This negative aspect can be largely minimized through the use of heterogeneous technology, when fuel gas is fed directly into the cylinder of a dual-fuel engine under high pressure, up to 50 bar, at the end of the compression process. This technology is becoming widespread in the structures of two-stroke engines due to the specifics of their gas exchange process. However, the high dynamics of the heat release process in the implementation of heterogeneous technology of gas-air mixtures is associated with a high emission of nitrogen oxides, commensurate with the emission of NOx by a diesel engine. Based on the analysis of the parameters and characteristics of the products of leading manufacturers implementing various technologies for using natural gas as fuel, conclusions about the potential advantages and prospects of using gas and dual-fuel engines are made.
IMPACT OF FLOODS IN THE KOLYMA RIVER DELTA ON NAVIGATION CONDITIONS IN THE EAST SIBERIAN SEA
Authors: Kholoptsev Aleksandr V. , Podporin Sergey A.
Published: December 2022

The problem of improving the quality of medium- and long-term forecasting of changes in the ice situation on the Northern Sea Route, and in particular in the East Siberian Sea, where one of the methods for choosing waterways is the passage of vessels in the areas of flaw polynya, is considered. The hypothesis that in the summer months such changes can be significantly affected by the terms of floods onset in the Kolyma River Delta is tested. The data of the GLORYS12v1 global reanalysis supported by the Copernicus Marine Service are used as factual material on the ice cover and levels of the East Siberian Sea in the months from May to October of 1993-2019. The reanalysis is based on mathematical models of the NEMO family, verified using altimetry data from satellite measurements. Using the developed methodology for the selected periods of the year, the dates of sharp changes in the level and ice cover on the pre-estuary seaside of the Kolyma River are estimated. Using statistical methods, the validity of the stated hypothesis for a number of the East Siberian Sea areas, along which the shipping lanes of the Northern Sea Route pass, is confirmed. It has been established that the greatest influence of the floods terms on the ice situation and navigation conditions in such areas takes place in July. It has been shown that early floods in the Kolyma delta generally lead to an improvement in the ice situation, and late floods lead to its complication. The identified relationships are recommended for use in forecasting changes in ice conditions. The assumption that with further climate warming and a shift in the flood terms to earlier dates, it is possible that the ice conditions will become more complicated due to the freezing of the formed polynya, is made.
EXPERIMENTAL EVALUATION OF THE ANTIVIBRATOR TECHNICAL CONDITION
Authors: Pokusaev Mikhail N. , Gorbachev Maksim M. , Ibadullaev Adel D.
Published: December 2022

One of the key problems that have developed today in the fleet during the operation of ships is the termination of supplying products from leading foreign manufacturers of dampers and antivibrators of torsional vibrations, which ensure the safe operation of critical elements of the engine complex. Also, the next confirmation of relevance is the fact that there are no maintenance service centers on the territory of the Russian Federation, nor specialists who carry out the defection and repair of such devices. The results of experimental studies to assess changes in the technical condition of the antivibrator, which is the driven part of the clutch disc of a well-known foreign manufacturer for a KAMAZ truck, at the laboratory stand of the Marine Technology Service testing center of the Astrakhan State Technical University, are presented in the paper. The purpose of the tests is to evaluate the changes in vibration and torsional vibrations occurring in the elements of the laboratory stand at different states of the damping springs of the antivibrator. It should be noted that this device is used on YAMZ-236 engines, which is convertible on the ship. The change in the technical condition of the antivibrator is ensured by a complete limitation of the stroke (jamming) of the damping springs. Mechanical jamming is performed sequentially for each spring package and by measuring tangential stresses in the shaft of the laboratory stand and vibration acceleration on the bearing assembly rack. To conduct the experiments, the measuring base of the test center, including a torsional vibration monitoring system, a 1st class vibrometer, an Ecophysics-110 spectrum analyzer, etc., is used. It has been experimentally established that when the free travel of the damping springs of the anti-vibrator is completely limited, tangential stresses in the shaft and vibrations on the bearing assembly of the laboratory stand increase. It is also determined that the average tangential stresses in the shaft are more effective in terms of the criterion for diagnosing the antivibrator technical condition than the maximum stresses. The most informative for antivibration diagnostics are the octave frequencies of 4, 63 and 125 Hz, at which there is a significant change in vibration acceleration along all three axes X, Y, Z, depending on the number of jammed springs. The accumulation of theoretical and practical research in this area, in the future, may lead to the development of a methodology for the non-selective assessment of the technical condition of ship mechanical dampers and antivibrators of torsional vibrations.
STREAMING NETWORK ROUTING BASED ON BELLMAN-FORD ALGORITHM MODIFICATION
Authors: Chertkov Alexandr A. , Kask Yaroslav N. , Ochina Ludmila B.
Published: December 2022

The operational task of automating the construction and routing of the network model with the known coordinates of the conditional goals set for a group of vessels to achieve them in the minimum time is solved; it makes it possible to obtain the reserves of running time necessary for saving fuel and energy, taking into account the load, the cost of cargo, transportation costs, logistics characteristics, etc. It is emphasized that in stormy weather conditions and vessel management in situations related to schedule correction, flexible operational decisions of dispatching services, made on the basis of numerical optimization methods using modern computing environments, are necessary. In this regard, the method of dynamic programming, implemented using the Bellman-Ford routing algorithm, which is supplemented by a recursive step-by-step optimization procedure that removes the limitation of the algorithm in the presence of inversely oriented edges with negative weights in the graph, is discussed in the paper. In the presence of negative weights, there are conditions for the appearance of a negative cycle in the graph, in which the practical implementation of the Bellman-Ford algorithm will become impossible due to an endless cycle of relaxations (attenuation) of the vertices weights included in this cycle. Hence, at a limited period of time for weighing all vertices (passes on all edges), the algorithm can give a knowingly false result. The proposed procedure for modifying the well-known Bellman-Ford algorithm eliminates this limitation and allows it to be used not only for estimating the shortest paths in a network containing arcs with negative weights, but also to detect negative cycles in it. The modified Bellman-Ford algorithm is implemented as a program compiled in MATLAB codes, and it is demonstrated by the example of automated construction and calculation of a network model containing both positive and negative edges (flows), using a recursive procedure of step-by-step optimization. It is shown that the proposed model, unlike the known models, eliminates the limitations caused by the presence of negative cycles in the network model, which makes it possible to automate the search for the shortest paths to conditional goals by the functional means of the MATLAB environment. The constructed computer model is simple and compact. The proposed algorithm and the recursive procedure are recommended for finding energy-efficient solutions for managing mobile objects in water transport.
ELECTRIC CYLINDER AS A PROMISING TYPE OF ELECTROMECHANICAL DRIVE OF THE MAIN DOUBLE-LEAF GATES OF SHIPPING LOCKS IN RUSSIA
Authors: Saushev Alexander V. , Temkin Anton A.
Published: December 2022

The electric cylinder as a promising type of electromechanical drive for controlling the main miter gates is analyzed based on domestic and foreign experience. It is shown that, for a number of reasons, several different types of electric drives are in operation in Russia, differing from each other in kinematic schemes, operating parameters, dimensions and operational costs. Variety of electric drives types reduces their serviceability, requires the search for spare elements, the performance of repair work by third-party organizations, which, in turn, reduces the productivity of the gateway process. The operated electromechanical and electrohydraulic inputs of the main double-leaf miter gates of navigable locks with a chamber width of about 18 meters are analyzed. It is shown that the results of the drives comparison make it possible to clarify the calculations of the required power and load capacity, to contribute the development of a single regulatory document regulating the process of designing and selecting the operating parameters of an electric cylinder for specific operating conditions. The data compiled on the basis of foreign and domestic experience in the operation of different types of double-leaf miter gate drives, trends in their development, the reasons for their replacement with more modern drives are obtained. Special attention is paid to the disclosure of the reasons for replacing standard drives with an electric cylinder during the locks reconstruction. It is shown that the accurate calculation of the actually required performance indicators and the correct choice of the electric drive type, based on the conditions of future operation, lead to a noticeable increase in the life cycle of the shipping lock and its mechanisms.