211 research outputs found
Morphology of Camellia Sinensis L. leaves as marker of white tea authenticity
Received: February 1st, 2021 ; Accepted: April 24th, 2021 ; Published: August 18th, 2021 ; Correspondence: [email protected] is one of the most common drinks in the world. Classic tea is obtained by brewing
the leaves of the Camellia sinensis L plant in hot water. However, even the leaves collected from
the same branch of the same tea bush can have completely different anatomical, biochemical and
taste characteristics. White tea is the youngest, immature apical leaves of the tea bush (fleshes)
together with leaf buds (tips) which are is considered the most valuable parts of teaplant.
The chemical composition of tea is studied in sufficient detail, however, there are still no uniform
criteria for determining the authenticity of white tea leaves, which creates great preconditions for
falsifying this most valuable type of raw material. The aim of this study was to study the macroand microstructure of white tea leaves from different manufacturers and to determine the
morphological markers of the authenticity of white tea leaves.
The objects of research were white tea from the Nandana Tea Factory (Sri Lanka) and white tea
from an unknown manufacturer, purchased from a local tea shop.
The study of raw materials was carried out in accordance with the requirements of GF XIV OFS
1.5.1.0003.15 ‘Leaves’ and OFS 1.5.3.0003.15 ‘Technique of microscopic and microchemical
examination of medicinal plants and herbal medicinal products.’
The work was carried out on the basis of the laboratories of the Department of Food Technologies
of FGBOU VO Saratov GAU named after N.I. Vavilov, and the Department of General Biology,
Pharmacognosy and Botany, Saratov State Medical University named after V.I. Razumovsky
Ministry of Health of Russia.
Studies of the structure of white tea leaves from various manufacturers have shown that the
structure and presence of morphological elements of leaves, such as hairs, stomata, leaf edge,
druses, sclereids, differ markedly and can serve as reliable markers for identifying the variety of tea
The effect of bean flour addition on the rheological properties and baking quality of a triticale flour blends
Received: February 6th, 2021 ; Accepted: April 2nd, 2021 ; Published: August 18th, 2021 ; Correspondence: [email protected] aim of this research work was to study and compare the main parameters of the
rheological state of the dough made from triticale flour (a variety of George selection by the
FSBIS Agricultural Research Institute of the South-East), dough made from flour of white and
red bean seeds, as well as parameters of dough from flour of composite mixtures based on them.
The rheological properties of the dough were determined using a Mixolab device according to
the GOST ISO 17718-2015 method. The mixing ability of the blends was additionally tested by
the SDS sedimentation method. It was found that the moment of force, which characterizes the
gelatinization process, correlates well with the SDS sedimentation index. To a lesser extent, this
indicator correlates with the values of the moments of force characterizing the process of ‘starch
retrogradation’ and the energy intensity of the dough formation process. The water absorption
capacity of flour highly correlates with the moment of force during the liquefaction phase and
with the moments of force characterizing the minimum and maximum consistency of the dough
during the ‘starch retrogradation’ phase. The correlation between the SDS sedimentation rate and
water absorption capacity was found to be rather low. The rheological parameters were also
significantly influenced by the type of beans. Taking into account the results of studies of the
rheological state of the dough, test baking of bread with various mass fractions of components
was carried out. The results obtained confirmed the improving effect of bean flour
Muscle trematode infection of alien cyprinids in the basin of the Middle Ob (Sibiria, Russia)
The book represents proceedings of Sixth International Symposium “Invasion of Alien Species in Holarctic. Borok -VI” (11 Oct. – 15 Oct. 2021, Borok – Uglich, Russia). The wide spectrum of problems related to appearance and spread of invasive plants and animals is discussed. The book may be interested for specialists in many fields, such as limnologists, hydrobiologists, ecologists, botanists, zoologists, geographers, managers of dealing with nature preservation and fisheries
Transbronchial Guidance for Balloon Pulmonary Angioplasty in CTEPH: The Safe Guidewire Passage Through the Occlusion
[No abstract available
The role of non-commercial cyprinids in maintenance and spread of the opisthorchiasis focus in the middle Ob River basin (Tomsk region, Russia)
The study assessed the role of non-commercial cyprinid species in maintaining the opisthorchiasis focus in the middle Ob River basin, Tomsk region, Russia. The source of O. felineus infection for humans and carnivores is fish of the family Cyprinidae. This is the most numerous family, 14 species live in the middle Ob River basin, which includes 6 commercial species and 8 non-commercial species. This study aimed to investigate the current situation on infestation of non-commercial cyprinids with O. felineus metacercariae and their role in maintaining and spreading the natural focus of opisthorchiasis in the middle Ob River basin. We investigated 4 non-commercial species (tench, sunbleak, common bleak, gudgeon), which are highly abundant in water bodies. Tench, common bleak and gudgeon are objects of amateur fishing. These species are traditionally included in the diet of the local population. Opisthorchis felineus metacercariae were recorded in muscles of all the examined fish species. The identification of metacercariae was confirmed by morphological methods and PCR diagnostics. Tench and sunbleak are the main sources of opisthorchiasis infection in the floodplain lakes of the Ob River basin (the prevalence of tench infection is 89.3% and mean intensity of infection is 11.2 metacercariae per fish, the prevalence of sunbleak infection is 50.9% and the intensity of infection is 4.25 metacercariae per fish). The prevalence of infection in the introduced common bleak from the rivers of the middle Ob River basin is rapidly increasing from 2.4 (2016-2018) to 37.5% (2020-2021), and mean intensity of infection increased from 1 to 4.15. The epizootic state of water bodies in the middle Ob River basin remains unfavorable in relation to opisthorchiasis. Tench, common bleak and sunbleak, along with ide and dace, are the main source of infection for humans and animals, which is evidenced by high infection with Opisthorchis felineus metacercariae in these numerous fish species. They pose the greatest danger of infection of people and animals with opisthorchiasis. These species should be included in the campaign to avoid raw and poorly cooked fish in the diet. In addition, such species as roach, bream and sunbleak also pose the danger of infection with opisthorchiasis, but to a lesser extent
First record of the invasive mosquito species Aedes koreicus (Diptera, Culicidae) in the Republic of Kazakhstan
The natural distribution range of Aedes koreicus is Korea, China, Japan, and the Russian Far East. Since 2008, this species has been recorded as an invasive species in some European countries (Belgium, European Russia, Germany, Hungary, Italy, Slovenia, and Switzerland). The invasive mosquito species Ae. koreicus is reported from the Republic of Kazakhstan for the first time. Its morphological identification was confirmed by molecular-genetic analyses of ND4 sequences using specific primers. Aedes koreicus larvae were found in an artificial water reservoir together with the larvae of Culiseta longiareolata and Culex pipiens s.l. Aedes koreicus successfully overwintered in Almaty at low winter temperatures in 2018–2019. This suggests that the Ae. koreicus acclimation capacity is greater than it has been considered until now. We assume that Ae. koreicus will spread over the west and south of the Republic of Kazakhstan and territories of Kyrgyzstan and Uzbekistan Republics bordering the Almaty region
The World Largest Focus of the Opisthorchiasis in the Ob-Irtysh Basin, Russia, Caused by <em>Opisthorchis felineus</em>
The world’s largest focus of opisthorchiasis caused by cat fluke Opisthorchis felineus Rivolta, 1884, is associated with the Ob-Irtysh basin (Russia). The chapter provides data on the history of discovery and the study of opisthorchiasis. Features of the morphology and life cycle of O. felineus are described. Data on the infection of intermediate hosts (mollusks and cyprinids fish) are provided. Species of fish that have important epizootological significance are indicated. The incidence of opisthorchiasis in the people of different age and social groups, clinical manifestations, pathogenesis, and complications is discussed. The climatic and social factors that contribute to maintaining the focus of opisthorchiasis are described. The measures of personal and social prevention of the people are given
Tuning Pt characteristics on Pt/C catalyst for aqueous-phase reforming of biomass-derived oxygenates to bio-H-2
Pt/C catalysts with varied Pt sizes and distributions were investigated for aqueous-phase reforming (APR) of ethylene glycol (EG) to H2. APR experiments were performed on a continuous-flow fixed bed reactor with a catalyst loading of 1 g and EG feeding of 120 mL h−1 at 225 °C and 35 bar for 7 h. The fresh and used Pt/C catalysts were characterized by XRF, BET, CO chemisorption, TEM, XTEM, and XPS. Catalyst preparation protocols changed Pt characteristics on Pt/C catalysts, leading to a distinguishable H2 production. The rates for EG conversion and H2 production increased linearly with mean Pt size (3–11 nm), while having a volcano relationship with the mean size of agglomerated Pt particles (17–30 nm). Pt with concentrated Pt particles on surface of Pt/C catalysts was more preferable for APR of EG than the homogeneously distributed in catalysts. Optimal performance was obtained over a Pt/C-PR catalyst, which was prepared by precipitation method, showing a superb turnover frequency of 248 molH2 molPt−1 min−1 for H2 production from EG in APR. Besides, Pt/C catalysts also showed excellent stability. These results have shown the promise of Pt/C catalyst for APR of EG, which can be extended for bio-H2 production via APR of biomass-derived oxygenates in waste streams
АКТУАЛЬНІ ПРОБЛЕМИ СПІВРОБІТНИЦТВА З ОРГАНІЗАЦІЯМИ ІНОЗЕМНИХ ДЕРЖАВ У СФЕРІ СУДОВО-ЕКСПЕРТНОЇ ДІЯЛЬНОСТІ
The article shows the role of international cooperation in the field of forensic expert activity. On development of forensic expert institutions of the Ministry of Justice of Ukraine and the expansion of the possibilities for forensic examinations have a positive effect their activity in the implementation of international contacts: the organization of joint international scientific and practical conferences, seminars, internship of specialists with the purpose of sharing work experience, training of forensic experts, familiarization with the organization of activities and advanced methods of conducting forensic examinations and expert studies, allows a specialist there constantly to be aware of the latest achievements of science and to use the experience of their colleagues from other countries. Currently, work is underway to conduct joint scientific developments, training of highly qualified scientific personnel, but this is not specified in Art. 24 of the Law about forensic science, and therefore we propose this article be amended as follows: "State specialized institutions that perform forensic examinations are entitled establish international scientific ties with the institutions of forensic science, criminalistics and so on other states for the purpose of joint research and development, exchange of scientific and methodological information and printed publications, use of common international information funds, data banks, training, retraining and advanced training of forensic experts, international conferences, symposia, seminars, joint publications in forensic science and criminalistics, training of highly qualified scientific personnel". In connection with the further development of international cooperation, it is desirable in the staffing of forensic institutions to provide for such a structural unit as the International Relations Department. In 2018, KhRIFE obtained the Accreditation Certificate for compliance with the requirements of the international standard ISO/IEC 17025. The collection of scientific proceedings "Theory and Practice of Forensic Science and Criminalistics" is included in the international scientometric database Index Copernicus. The development of international cooperation in the field of forensic science will contribute to enhancing the scientific and methodological potential of forensic expert institutions, developing new directions and types of forensic expert activity, and increasing the effectiveness of the fight against crime.Показана роль международного сотрудничества в области судебно-экспертной деятельности. На развитие судебно-экспертных учреждений Министерства юстиции Украины и расширение возможностей судебных экспертиз положительно влияет их деятельность по осуществлению международных контактов: организация совместных международных научно-практических конференций, семинаров, стажировок специалистов с целью обмена опытом работы, обучение судебных экспертов, ознакомление с организацией деятельности и передовыми методами проведения судебных экспертиз и экспертных исследований, позволяет специалистам постоянно находиться в курсе последних достижений науки и использовать опыт своих коллег из других стран. В настоящее время осуществляется работа по проведению совместных научных разработок, подготовке научных кадров высшей квалификации, однако в статье 24 Закона о судебной экспертизе это не указано, в связи с чем предлагаем ее изложить в такой редакции: «Государственные специализированные учреждения, выполняющие судебные экспертизы, пользуются правом устанавливать международные научные связи с учреждениями судебных экспертиз, криминалистики и так далее других государств с целью проведения совместных научных исследований и разработок, обмена научно-методической информацией и печатными изданиями, использования общих международных информационных фондов, банков данных, проведения подготовки, переподготовки и повышения квалификации судебных экспертов, международных конференций, симпозиумов, семинаров, осуществления совместных изданий в области судебной экспертизы и криминалистики, подготовки научных кадров высшей квалификации». В связи с дальнейшим развитием международного сотрудничества желательно в штатном расписании судебно-экспертных учреждений предусмотреть такое структурное подразделение, как отдел международных связей. В 2018 году ХНИИСЭ получил Аттестат об аккредитации на соответствие требованиям международного стандарта ISO/IEC 17025. Сборник научных трудов «Теория и практика судебной экспертизы и криминалистики» включен в международную наукометрическую базу данных Index Copernicus. Развитие международного сотрудничества в области судебной экспертизы будет способствовать повышению научно-методического потенциала судебно-экспертных учреждений, разработке новых направлений и видов судебно-экспертной деятельности, повышению эффективности борьбы с преступностью.Міжнародне співробітництво є одним із важливих напрямів роботи судово-експертних установ і закладів вищої освіти України, зокрема, Харківського науково-дослідного інституту судових експертиз ім. Засл. проф. М. С. Бокаріуса та Харківського національного медичного університету. Одним із результатів міжнародної співпраці є удосконалення законодавства України і його адаптація до норм міжнародного права. Нині міжнародні взаємовідносини у сфері здійснення судово-експертної діяльності є недостатньо врегульованими, що потребує більш детального опрацювання нормативно-правових актів в аспекті міжнародних договірних відносин. Запропоновано шляхи вдосконалення норм чинного законодавства та діяльності судово-експертних установ Міністерства юстиції України
Experimental Stand for Investigations of Insulator Degradation and Electrode Erosion in High-current Breaker
An experimental stand for studies of electric arc, electrode erosion and insulator degradation processes in high-current circuit breakers and some preliminary experimental data is described. The setup includes a discharge chamber, a capacitive energy storage with capacitance of 0.11 F, voltage up to 10 kV, and all necessary diagnostic techniques. The stand is designed for modeling current pulse with amplitude of 3–150 kA and duration of the first half period of 1.0–3.0 ms during the process of disconnecting the ring and the pin contacts. The arc is cooled by transverse gas blowing at pressure in the chamber of 0.5–3 MPa. Acquired experimental data can be used for verification of the modelling results of the heat transfer processes in the discharge chamber. At the stand, advanced composite materials based on carbon and iron-copper pseudoalloy are studied
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