bluuebunny/crossref_metadata_2025 huggingface dataset:
Splitting of PG(1,27) by Sets, Orbits, and Arcs on the Conic
Authors: Abdulkareem Emad Bakr
Published: July 2021

This research aims to give a splitting structure of the projective line over the finite field of order twenty-seven that can be found depending on the factors of the line order. Also, the line was partitioned by orbits using the companion matrix. Finally, we showed the number of projectively inequivalent -arcs on the conic  through the standard frame of the plane PG(1,27)
Placement Inverse Source Problem under Partition Hyperbolic Equation
Authors: Hussein Shilan Othman
Published: July 2021

In this article, the inverse source problem is determined by the partition hyperbolic equation under the left end flux tension of the string, where the extra measurement is considered. The approximate solution is obtained in the form of splitting and applying the finite difference method (FDM). Moreover, this problem is ill-posed, dealing with instability of force after adding noise to the additional condition. To stabilize the solution, the regularization matrix is considered. Consequently, it is proved by error estimates between the regularized solution and the exact solution. The numerical results show that the method is efficient and stable.
TEOREMA TITIK TETAP DI RUANG NORM-2 (R n, k., .k2)
Authors: MARWAN MARWAN , EKARIANI SHELVI , HARIPAMYU HARIPAMYU
Published: July 2021

Pada penelitian ini akan dibahas teorema titik tetap di ruang norm-2 (Rn, k., .k2). Teorema titik tetap merupakan teorema yang menyatakan eksistensi dan ketunggalan titik tetap. Norm-2 k., .k2 didefinisikan sebagai kx, yk2 := det x Â· x x Â· y y Â· x y Â· y 1 2 dengan x, y âˆˆ Rn. Pasangan terurut ruang vektor Rn dengan norm-2 k., .k2 disebut ruang norm-2(Rn, k., .k2). Ruang norm-2(Rn, k., .k2) merupakan ruang banach artinya ruang norm-2(Rn, k., .k2) bersifat lengkap. Ruang norm-2(Rn, k., .k2) bersifat lengkap dibuktikan dengan cara menunjukkan ekivalensi antara norm dengan norm baru. Norm baru ini dibagun dari norm-2 k., .k2 dengan menggunakan dua vektor yang bebas linier. Teorema titik tetap menyatakan jika pemetaan T : Rn â†’ Rn dari ruang norm-2 lengkap (Rn, k., .k2) merupakan pemetaan kontraktif maka T memiliki titik tetap yang tunggal.Kata Kunci: Norm, Ruang norm-2, Teorema Titik Tetap.
HUBUNGAN RUANG NULL DAN RUANG PETA PADA MATRIKS IDEMPOTEN
Authors: ANJELI PUTRI RATIH , YANITA YANITA , RIANTI HELMI MONIKA
Published: July 2021

Ruang null dari matriks A yang berukuran m Ã— n adalah himpunan semua solusi untuk persamaan Ax = 0 dan ruang peta dari matriks A yang berukuran m Ã— n adalah himpunan semua solusi untuk persamaan Ax = y. Misalkan matriks A berukuran n Ã— n dikatakan matriks idempoten jika A2 = A. Matriks A dan B adalah Dua matriks idempoten dikatakan komutatif nol jika AB = BA = O. Tulisan ini mengkaji hubungan ruang null dan ruang peta pada matriks idempoten.Kata Kunci: Ruang Null, Ruang Peta, Matriks Idempoten.
SOLUSI PERSAMAAN DIFERENSIAL ORDE DUA DENGAN SYARAT BATAS FRACTIONAL (KASUS AKAR KOMPLEKS)
Authors: YOLANDA DEBBY , RUDIANTO BUDI
Published: July 2021

Dalam artikel ini dikaji solusi persamaan diferensial biasa linier orde dua homogen dengan syarat batas berupa turunan fractional. Kajian ini khusus untuk persamaan karakteristik dari persamaan diferensial orde dua dengan akar bilangan kompleks murni. Turunan fractional yang digunakan dalam skripsi ini adalah turunan fractional Riemann-LiouvilleKata Kunci: Persamaan diferensial biasa linier orde dua homogen, Akar kompleks, Turunan Fractional Riemann-Liouville.
PEMBENTUKAN PORTOFOLIO OPTIMAL BERDASARKAN INDEKS KINERJA KEUANGAN PADA SAHAM LQ-45
Authors: MUTIASALISA DIRAMADHONA , DEVIANTO DODI , RAHMI HG IZZATI
Published: July 2021

Investasi adalah suatu bentuk penanaman dana guna memberikan keuntungan tingkat pengembalian (return) baik pada masa sekarang atau dan dimasa depan. Saham adalah sebuah bukti kepemilikian nilai sebuah perusahaan. Saham merupakan salah satu instrumen investasi yang paling menarik karena memiliki mobilitas yang tinggi. Indeks kinerja keuangan yang dimaksud adalah Indeks Sharpe, Treynor dan Jensen dimana merupakan metode yang digunakan untuk mengukur kinerja keuangan suatu saham, sehingga ketiga metode tersebut dapat digunakan sebagai dasar untuk membuat sebuah portofolio. Portofolio adalah sekelompok instrumen investasi yang dipilih sebagai objek investasi dari seorang investor atau sebuah perusahaan investasi. Pada Penelitian ini data yang digunakan adalah return dari 45 saham berindeks LQ-45 pada periode Februari 2020 - Juli 2020. Menurut hasil perhitungan nilai Indeks Sharpe, Treynor dan Jensen dapat ditarik kesimpulan bahwa saham yang memiliki kinerja keuangan terbaik adalah Sarana Menara Nusantara Tbk (TOWR), Kalbe Farma Tbk (KLBF), Surya Citra Media Tbk (SCMA), Aneka Tambang (Persero) Tbk (ANTM), dan Ace Hardware Indonesia Tbk (ACES). Ketika saham yang berkinerja keuangan baik menurut Indeks Sharpe, Treynor dan Jensen disatukan sebagai sebuah portofolio maka dapat dikatakan portofolio tersebut adalah portofolio optimal berdasarkan indeks kinerja keuangan.Kata Kunci: Indeks Sharpe, Indeks Treynor, Indeks Jensen
Influences of polymer modifiers on Porous Hot Asphalt Mixture Property and Durability
Authors: Ali Mohammed Q. , Khoshnaw Ganjeena J.
Published: July 2021

Fundamentally, sustainability and cost-effectiveness in infrastructure development have received widespread attention. Permeable pavement is such a concept that it is sustainable in the field of transportation and is being tested. Fully permeable pavement is a modern design method in which each layer is porous and can store water, avoiding the impact of stormwater on the pavement to avoid stormwater, skidding, floods, and water splash on the road and parking area which decrease safety rate. Porous asphalt (PA) is an asphalt mixture with a little or no fine aggregate. Due to open structures and advantages are used as a drainage layer in highway pavements in reducing noise and decreasing safety hazards during rainfall. Besides, it reduces splash and spray effects and thus increases the visibility. The main aim of this study is to analyze the influence of two asphalt modifier types: Styrene butadiene styrene (SBS) and propylene modifier polypropylene (PP), on porous hot asphalt mixture performance. The PA evaluation influence findings are based on permeability, durability, and Marshall stability-flow for hot asphalt mixture. The test results emphasize the modifier usage in reducing the abrasion loss and increasing the stability with enhancing the durability of PA. PA mixture binder prepared with 4% SBS and 4% PP modifier was the most polymer binder in modifying the abrasion resistance and stability of mixture in pavements.
Histopathological Diagnosis of Peptic Ulcer Biopsies in Koya City, Kurdistan Region, Iraq
Authors: Salih Mehri M.
Published: July 2021

Peptic ulcer disease is the common gastrointestinal disorder, which affects the high number ofpeople during their life. The present study was carried out among 267 patients with different uppergastrointestinal symptoms, at the Department of Endoscopy, Shahid Dr.Khalid Hospital/in Koya cityduring 1/2018-1/2019, all patients were assessed endoscopically and biopsies from both antral andbody mucosa were taken for histopathological examination. The aim of this study was to determinethe spectrum of histopathological biopsies of the gastric region with the distribution of peptic ulcerbiopsies according to age and sex in Koya city, Kurdistan Region, Iraq. The study showed normalgastric mucosa histopathologically in 22 (8.24%) cases and 245 (91.76%) abnormal gastric mucosahistopathologically. Gastritis histopathologically was seen in 217 (81.27%) of cases, chronic gastritisrepresented the highest relative frequency in this histopathologically diagnosed patients, where it wasseen in 65.89% of the cases and acute gastritis was detected in 34.10% of the cases. Helicobacterpylori was detected in 82.77% of patients. A significant association was detected between chronicgastritis and H. pylori infection.
Mobile Application Development to Measure Smartphone Screen Readability
Authors: Yanto Yanto , Mulyani Fransisca Cindy
Published: July 2021

This study aimed to develop an application which can be used to measure the response time needed by subjects to find a set of predetermined “words” in order to determine the level of readability of smartphone screen. The development steps began with concept development, interface design and software testing and verification. The results of this study is a software which can be used for typography experiment in which the subject is asked to find a predetermined word. The software could be used for the experiment of 4 typography factors i.e font style (FS), font size (FZ), contrast (CT), and screen rotation (SR). This software could be used for the 5x3x2x2 factorial experiment with 60 combinations. The response time of subject for each treatment combination has been computed and saved in the smartphone. Finally, the response time could be used to determine the best combination of factor and level factor for readability of smartphone screen.
Estimating Spillover Effect and Leverage Effect Using EGARCH-ARMA Approach in Mongolian Stock Exchange
Authors: Lee Cheng-Wen , Gankhuyag Dolgion
Published: July 2021

This study checked the spillover effect and leverage effect from 2 January 2012 to 27 December 2017 in the Mongolian Stock Index MSE20 time frame. We found spillover effect on individual stock prices from the market index, but our analysis did not support individual stock has a spillover effect on stock index. In terms of volatility, only market and stock volatility have a bilateral spillover effect. Stock index in particular has a much stronger influence on stock price. Our research did not support previous studies for the leverage effect of the EGARCH-ARMA method, suggesting negative asymmetric influence of volatility such that two financial instruments overlap in their value.
Rancang Bangun Alat Sentrigufal Pencuci Daging Buah Kelapa Menggunakan Cairan Air Kelapa (Pre-Processing Metode Sentrifugasi)
Authors: Santosa Hadi , . Yuliati , Mulyana Ig. Jaka
Published: July 2021

The diversification of the coconut processing industry into Virgin Coconut Oil (VCO) as a more prospective coconut derivative is currently still growing rapidly. VCO is a virgin coconut oil product that is beneficial for health, and can be used as a raw material for natural cosmetics which has high economic value. Preliminary research has successfully designed the construction of a coconut husk peeler and a coconut shell breaker machine as an early stage in the VCO production process technology. The discussion of this paper covers the design of a coconut meat washing machine utilizing coconut water which consists of a rotating tube with an adjustable tube rotation speed with an inverter and an electric motor as the driving force equipped with a high pressure nozzle with ± 75 psi pressure. Inside the tube there is a retaining divider that regulates the flow of the washed coconut meat. The washing process uses coconut water to wash coconut meat in a washing tube that rotates at a certain speed as needed with a capacity of 8 kg timer for ± 3-5 minutes. Coconut water is drained and coconut meat is ready for the next process.
Tıp Fakültesi Öğrencilerinin Probleme Dayalı Öğrenmeye İlişkin Görüş ve Tutumları
Authors: AYBEK Hülya , ÇERMİK Hülya , ALİMOĞLU Mustafa Kemal
Published: July 2021

Amaç: Bu çalışmanın amacı, tıp fakültesi öğrencilerinin probleme dayalı öğrenmeye (PDÖ) yönelik görüş ve tutumlarını belirlemek ve bu görüş ve tutumlar üzerindeki olası etkili faktörleri araştırmaktır.Yöntem: Çalışma tanımlayıcı bir anket modeli olarak tasarlanmıştır. Veriler, PDÖ müfredatı uygulayan Pamukkale Üniversitesi Tıp Fakültesi'nde eğitim gören 569 tıp öğrencisinden toplanmıştır. Öğrencilerin PDÖ’ye yönelik görüş ve tutumları üzerinde olası etkili faktörler cinsiyet, mezun olduğu lise türü, öğrenim gördükleri dönem ve kendilerine yeni bir şans verilse tıp eğitimine devam etme/me tercihleri olarak düşünülmüştür. Görüş ve tutumların birbirini etkileyebileceği ihtimaline ilişkin olarak, aynı zamanda aralarındaki ilişkiyi de araştırılmıştır. Veriler, “kişisel gelişim”, “mesleki gelişim” ve “öğrenme süreci” olarak 3 boyuttan oluşan ‘PDÖ’ye yönelik öğrenci görüş ölçeği’ ve olumlu ve olumsuz maddeler içeren ‘PDÖ tutum ölçeği’ kullanılarak toplanmıştır.Bulgular: “PDÖ’ye yönelik öğrenci görüş ölçeği” nin üç boyutuna verilen cevap aralıkları katılıyorum ve orta düzeyde katılıyorum şeklindedir. Öğrencilerin PDÖ konusundaki görüşleri cinsiyetlerine ve mezun olduğu lisenin türüne göre farklılık göstermemiştir. Ancak, tıp eğitiminin ilk yılında olan ve kendilerine yeni bir şans verilse tıp eğitimini bırakmak istemeyen öğrencilerin görüş puanları daha yüksektir. “PDÖ'ye yönelik tutum ölçeği” nin iki boyutuna verilen cevap aralıkları katılıyorum ve emin değilim şeklindedir. Öğrencilerin PDÖ'ye yönelik tutum puanları kadınlar, birinci sınıf tıp öğrencileri ve kendilerine yeni bir şans verilse tıp eğitimini bırakmak istemeyen öğrencilerde daha yüksektir. Mezun olduğu lise türü, öğrencinin PDÖ'ye yönelik tutumlarında etkisiz bulunmuştur. Öğrencilerin PDÖ'ye yönelik görüşleri ile PDÖ'ye yönelik tutumları arasında yüksek düzeyde anlamlı bir korelasyon bulunmuştur.Sonuç: Çalışma sonuçları öğrencilerin PDÖ ye yönelik tutumlarının olumlu olduğunu ve aynı zamanda PDÖ hakkında olumlu görüşleri olan öğrencilerin PDÖ ye yönelik tutumlarının da olumlu olduğunu ortaya koymaktadır.
Food supply for nekton in the epipelagic layer of Pacific waters at Kuril Islands in the summer seasons of 2000s
Authors: Naydenko Svetlana V. , Khoruzhiy Alexey A.
Published: July 2021

Data of 8 surveys conducted by Pacific Fish. Res. Center (TINRO) in the Pacific waters at Kuril Islands in 2004-2012 are summarized to consider forage base and food relationships of nekton and plankton and to estimate consumption of forage resourced by nekton. The total stock of zooplankton and micronekton in the epipelagic layer changed from 62 to 158 million tons over the shelf and slope of the surveyed area and from 41 to 75 million tons in its deep-water part. Mezopelagic fishes, squids, pacific salmons, and subtropical fishes were the main consumers of these forage resources in summer. The portion of zooplankton stock consumed annually by nekton was relatively low: 4.2-9.3 % for shelf and slope areas (data for 2004, 2007, and 2011) and 4.5-15.6 % for the deep-waters (data for 2004, 2007, 2009, and 2011), without significant year-to-year changes in the diet composition and feeding intensity of nekton. There is concluded that zooplankton and micronekton of the studied area serve successively the food needs of its consumers and carrying capacity of the epipelagic layer in the Pacific waters at Kuril Islands is quite substantial.
Feeding of adult sea bream Brama japonica in the Pacific Ocean and the Bering Sea
Authors: Efimkin Alexander Ya.
Published: July 2021

Feeding habits of adult sea bream are considered on the samples collected in the North Pacific and Bering Sea in the last several years. This species is a predator with the diet highly dependent on its habitat and composition of prey (small-sized fish and squids). It has two or three peaks of consumption daily, which change seasonally and year-to-year; anyway, the morning (3-6 a.m.) is usually the time of the lowest consumption, at least in summer and autumn, and the daytime is the normal time for feeding. The sea bream does not eat zooplankton usually, but Euphausia pacifica was a significant portion of its diet (34 %) in the southern part of surveyed area in the summer of 2009, possibly because of high concentrations of euphausiids in that area. Daily ration of adult sea bream is 2.5-3.5 % of its body weight.
Ice drift in Peter the Great Bay
Authors: Dubina Vyacheslav A. , Plotnikov Vladimir V. , Kot Nina S.
Published: July 2021

Dynamics of the sea ice cover in Peter the Great Bay is considered, for the first time for its whole area, on the base of satellite images received in 2004-2011 from the spectroradiometers MODIS mounted on the satellites Terra and Aqua. High spatial resolution maps of the ice drift are constructed for various wind conditions. Mean values of the drift velocity and wind coefficient are calculated for four parts of the Bay. In usual conditions of winter monsoon, the ice in the central part of Peter the Great Bay drifts southward with the velocity 0.5-0.6 m/s with deviation from the wind direction about 40° to the right; the ice at the western coast drifts along the island chain with the velocity 0.1-0.4 m/s under wind of any direction in the quadrant from northwest to northeast.
Abundance and distribution of pacific walrus Odobenus rosmarus divergens in vicinity of Cape Serdtse-Kamen in 2009-2013
Authors: Chakilev Maxim V. , Kochnev Anatoly A.
Published: July 2021

Results of the first special research of pacific walrus Odobenus rosmarus divergens at Cape Serdtse-Kamen conducted in the 2009-2011 and 2013 are presented. The coastal haulout place looks as series of relatively isolated areas (up to 36) located alongshore about 20 km from Cape Serdtse-Kamen to the Ikalyurynveem River mouth. Initially the walruses were on the northwestern edge of the haulout place between Cape Serdtse-Kamen and Cape Sulyn but expanded southeastward with increasing of their number. In the years with early and intense ice melting, the walruses come to the area in early September, and the haulout forms to the end of the first 10-day period of this month. In conditions of late ice retreat, as in the 2013, the walruses on the whole come to Cape Serdthse-Kamen later. The maximum number of walruses in this area was observed in 2009 (about 98,000 animals) and 2010 (118,500). This is the record number of walruses ever recorded simultaneously on one coastal haulout in the species range. Almost the whole Pacific population gathers in the vicinity of Cape Serdtse-Kamen for feeding in late autumn and continues to feed there until freezing of the Chukchi Sea. In spite of obvious significance of the area at Cape Serdtse-Kamen for the pacific walrus population, there still aren’t any special measures of their protection in this part of the coast when they are ashore - the measures are definitely necessary to prevent intensive economic activities in this key for the walruses area and to save the coastal haulout for traditional use of native people.
Zoning of waters in the Australian-New Zealand sector of the South Ocean by the example of distribution of pelagic ostracods from subclass Myodocopa
Authors: Chavtur Vladimir G. , Mazdygan Ekaterina R.
Published: July 2021

Distribution of mass antarctic, subantarctic, antarctic-subantarctic and tropical-subtropical interzonal pelagic ostracods is considered depending on structure and dynamics of waters in the Australian-New Zealand sector of the South Ocean on the base of authors’ and cited data. The species are separated latitudelly and vertically, that probably diminishes competition between them. Biogeographic boundaries of the subantarctic and antarctic zones determined by the ostracods distribution patterns are close to the South Polar and Subpolar Fronts.
Atresia of oocytes for northern rock sole Lepidopsetta polyxystra (Pleuronectiformes, Pleuronectidae) from the Pacific waters of Kamchatka
Authors: Dubinina Anna Yu. , Zolotov Alexander O.
Published: July 2021

Northern rock sole is abundant and important for fishery species in the Pacific waters of Kamchatka and northern Kuril Islands. Sometimes its oogenesis occurs with the oocytes atresia. By the data of the females reproductive tissue investigation conducted in 2011-2012, the degeneration appears for the late perinucleus (II and II-III maturing stages), vitellogene cells (III and IV stages), and ovarian follicles (stages VI-III) and develops by three principally different ways. Comparing with other fish species, atresia of the late perinucleus of northern rock sole realizes without follicular epithelium and affects either 15 % of these cells (for 8 % of juveniles) or 67 % of these cells (for 4 % of non-spawning adults). In the process of the vitellogene oocytes atresia, a symplast forms between follicular epithelium and chorion and conserves until final resorption of the oocyte. The cortical alveoli and vacuolated cells are damaged more often (5.6 %) than the oocytes with advanced yolk (2.4 %). Resorption of ovarian follicles by stroma connective tissue of oviparous plates is typical for all postspawning females, their portion doesn’t exceed 3 % of cells in each generation. Obviously, atresia of vitellogene oocytes reduces the fish fecundity, therefore the total and population fecundity is forming until the stage IV.
Influence of repeated intravital extraction of eggs from sturgeon hybrids on their oogenesis under conditions of recirculation aquaculture system
Authors: Filippova Olga P. , Piyanova Svetlana V. , Zuevsky Sergey E.
Published: July 2021

Dynamics of cytomorphological characteristics of oocytes in ovaries is considered for two sturgeon hybrids: besters of the breed Burtlevskaya Huso huso (Linnaeus) x Acipenser ruthenus (Linnaeus) and the breed Aksayskaya Acipenser ruthenus x ( Huso huso x Acipenser ruthenus ) on the experimental data obtained under controlled conditions in the aquatic complex in Moscow (Russia) in 2010-2012. Methods of intravital eggs extraction, ultrasound diagnostics, biopsy with the probe, anesthesia and histological analysis are applied. Structure of membrane is similar for straight sturgeon species and hybrids, but the membrane thickness and the term of its emergence on certain maturity stage are somewhat different, so the eggs of bester could be distinguished by the oocyte membrane thickness. Mean interspawning interval for the hybrids in conditions of recirculation aquaculture system at water temperature 20-21 °C is determined as 10-12 months.
Antibiotics in aquaculture and their ecological significance. A review
Authors: Shulgina Lidia V. , Yakush Eugeny V. , Shulgin Yury P. , Shenderyuk Vladimir V. , Chukalova Natalia N. , Baholdina Lidia P.
Published: July 2021

Retrospective data concerning effects of antibiotics used in aquaculture on disease incidence for cultivated animals and humans are analyzed. Danger of the antibiotics use is shown for those used for both therapeutic and prophylactic purposes. The antibiotics could be consumed by humans with the production of aquaculture or exuded to environments in quantities able to cause microbial imbalance or contribute to development of resistant bacteria forms. These consequences lead to significant economic losses.
Researching the conditions for renewing of fishing fleet by prospective types of large-tonnage vessels
Authors: Solomin Andrey I.
Published: July 2021

Cost efficiency of projecting, shipbuilding and exploitation of new types of fishing vessels is analyzed for several existing fishery enterprises. Running costs per a catch day are calculated for certain vessels projects and leasing terms; the leasing procedure is described; the break-even points are evaluated. There is concluded that large enterprises or corporations with high volume of production are able to conduct profitable exploitation of large-tonnage vessels.
First description of shark Isistius brasiliensis (Dalatiidae) in the waters of Russia
Authors: Dolganov Vladimir N.
Published: July 2021

Description of rare shark Isistius brasiliensis caught off southern Kuril Islands on July 18, 1978. Morphometric parameters are presented, including counts of dorsal and caudal vertebras, teeth rows, mitral valves, and intestinal helical valve coils.
Assessment of radiation environment in the South-Kuril fishing area and impact of radiation pollution on pacific saury in 2011-2013
Authors: Borisenko Galina S. , Blinov Yury G. , Filatov Victor N.
Published: July 2021

Radiation environment is assessed for the Pacific waters off Kuril Islands and effects of radiation pollution on pacific saury migrating through this area for feeding are evaluated on the samples collected by research vessels of Pacific Fisheries Research Center (TINRO) in 2011-2013 and processed in the specially equipped laboratory of this institute. Short-term increasing of the radiation background was registered in March 2011 only, and radiation pollution of the fish tissues was not detected. Obviously, the accident at the nuclear power plant Fukushima-1 had no significant effect on pacific saury. No threat to safety of the food made of pacific saury is concluded. However, a dangerous effect of the accident is possible for other commercial species of fish, in particular long-living ones that have repeated migrations through the waters adjacent to the power plant, as sardine and mackerel. These species aren’t landed by Russian fishermen now but their fishery can be resumed under growth of their populations in future.
Ecotoxicological assay of seawater quality on the western Kamchatka shelf
Authors: Lukyanova Olga N. , Zhuravel Elena V. , Chulchekov Denis N. , Mazur Andrey A.
Published: July 2021

Ecotoxicological assay of seawater quality along the shelf of West Kamchatka, including the areas of oil and gas deposits, was conducted in the summer of 2014. Temperature and salinity conditions were usual for summer season, as well as the field of density currents. For introduction of modern and representative bioassay methods in practice of environmental monitoring in the regions of oil and gas production and transportation, embryogenesis of sand dollar Scaphechinus mirabilis was used for biotesting. The stations with high number of the embryos and larvae abnormalities had mosaic distribution - this effect may be connected with shipping of fishing and merchant vessels.
Oncomonitoring of caspian sprats
Authors: Voronina Elena A.
Published: July 2021

Results of long-term research of tumorous disease in internals of two sprat species dwelling in the Caspian Sea ( Clupeonella delicatula and C. engrauliformes ) are presented. Pathological changes are similar for both species: they are mainly tumorogenesis and abnormalities in hemodynamics and morphology of parenchymatous and reproductive organs. The visceral neoplasms are diagnosed as malignant insulocarcinomas with conditionally pathogenic micromycetes in their granulomas (identified on smears of liver and spleen). Pathogenic Hyphomycetes fungi are detected in injured organs, mostly of the genus Aspergillus. The disease is registered for all age groups of fish but is more apparent for middle and elder ages. The morbidity has strong seasonal and year-to-year variability with the maximum in 2014. Pollution of marine environments contributes to development of the epizootic process.
Current abundance of spotted seal ( Phoca largha) in Peter the Great Bay (Japan Sea): unstable equilibrium or sustainable growth?
Authors: Trukhin Aleksey M.
Published: July 2021

Представлена информация о динамике численности популяции ларги, размножающейся в Дальневосточном морском заповеднике (зал. Петра Великого, Японское море). Современный размер ежегодного приплода оценивается в 750 детенышей при общей численности популяции (без учета приплода) - 3,0-3,2 тыс. особей. Результаты учетов свидетельствуют, что на протяжении последних полутора десятилетий численность местной популяции пребывает в состоянии устойчивого роста. Увеличение численности тюленей сопровождается возникновением новых крупных репродуктивных залежек на тех островах архипелага Римского-Корсакова, где полтора десятилетия назад эпизодически размножались единичные тюлени. Тенденция дальнейшего увеличения численности ларги в зал. Петра Великого сохраняется.
Some aspects of biogeography with reference to zoning of the Far- Eastern Seas of Russia and adjacent waters of the Pacific Ocean
Authors: Ivanov Oleg A. , Sukhanov Vitaly V.
Published: July 2021

Formation of biogeography, its methodological features, and its status as interdisciplinary science combining biological and geographical aspects are discussed. There is noted that the descriptive period of biogeography has passed, and now any «manifestation of life on the globe» requires its explanation. These explanations are reduced to three non-adversarial restrictions: environmental (ecology), temporal (history of origin, evolution), and spatial (geography). General regularities of life distribution over the Earth surface are analyzed, in particular the features of pelagic organisms habitat, and the concept of «dynamic biogeography» is discussed. Latitudinal zoning of epi- and mesopelagic layers in the Far-Eastern Seas of Russia and adjacent Pacific waters is proposed on the basis of data about areas and distribution of 493 species of nekton (fishes and squids) for the 30-year period (1980-2009) obtained from 27 thousand trawl samples caught in 272 expeditions. This zoning uses a new approach related to the chorological direction in marine biogeography realized with the index of latitudinal zoning (ILZ). For this index calculation, all types of species areas (formerly expressed in verbal forms) were identified with numerical codes, which were averaged for all species in each sample, then the regions with certain ILZ values and borders between them were determined on the maps of ILZ distribution, and latitudinal zones and subzones were defined. There is found that the epipelagic layer of the Okhotsk and Bering Seas corresponds to the high-boreal latitudinal subzone and the epipelagic layer of the northwestern Japan Sea and the major part of Russian EEZ in the Pacific corresponds to the low-boreal latitudinal subzone. Fauna of nekton in the mesopelagic layer of all studied regions corresponds by its chorological structure to the low-boreal latitudinal subzone. So, zoning of epipelagic and mezopelagic layers is significantly different, with the fragmentation reducing with depth, possibly due to weakening of climatic factors influence. The biogeographical zoning is not literally zonal but corresponds to structure of the environments (water masses, fronts, currents, gyres, eddies, etc.).
Feeding of smoothtongue Leuroglossus schmidti in the Bering, Okhotsk Seas and adjacent waters of the Pacific Ocean
Authors: Efimkin Alexander Ya.
Published: July 2021

Smoothtongue Leuroglossus schmidti is a small mesopelagic fish species common for subarctic waters. It rises to the upper epipelagic layer at night for feeding and preys mainly on euphausiids, copepods and amphipods. Its mean index of stomach fullness reaches 68 ‱ in the epipelagic layer, but it almost doesn’t feed deeper than 200 m, judging by a little food in the stomach. In the Bering Sea, euphausiids dominate in its diet and the portion of copepods is small. In the ​​Okhotsk Sea, each of these two groups provides a half of the diet. In the North Pacific, the portion of copepods is 63 % on average, euphausiids are the second important prey, and amphipods occur in the diet occasionally. Daily ration of smoothtongue is about 1.4 %.
Distribution of organic matter, phytopigments and heterotrophic bacteria along the salinity gradient in the estuaries of small rivers of the Tatar Strait basin
Authors: Garetova Ludmila A. , Levshina Svetlana I. , Fisher Natalia K. , Sirotsky Sergey E. , Shesterkin Vladimir P.
Published: July 2021

Distribution of total organic matter and its dissolved and suspended forms was investigated in two small estuaries with different morphometric characteristics, as Muchke and Toki Lakes, in late July 2014 at the low tide phase. The time of survey was distinguished by low river discharge and high tides. Content of all forms of organic matter and hydrocarbons was higher in the estuarine waters, as compared with fresh river water, regardless of salinity. The dissolved form prevailed (79.7-98.6 % of the total organic matter content) with concentrations of 5.2-35.7 mg/l. Chlorophyll a dominated (up to 87 %) among phytopigments in both estuaries that corresponded to active development of microalgae. Toki Lake was distinguished by higher productivity and microplankton abundance. On the contrary, allochthonous organic matter was more abundant in Muchke Lake, where interrelation between destructors (heterotrophic bacteria number) and primary producers (Chl a concentration) was observed. Oil-oxidizing microorganisms were up to 60 % of the heterotrophic bacteria number. The hydrocarbons content exceeded the maximal permissible level: 3.6 and 4.5 MPL in Muchke and Toki Lakes, respectively. Both estuaries were subjected to chronic hydrocarbon pressure.
Morphobiological description of deep-sea spotted ratfish Hydrolagus barbouri (Chimaeridae, Chimaeriformes)
Authors: Dolganov Vladimir N.
Published: July 2021

Morphological description is given for 31 specimens of spotted ratfish Hydrolagus barbouri caught at northeastern Japan and southern Kuril Islands in the 1980, including both male and female juveniles and adults. Counts for teeth enamel rods, prepelvic tenaculum hooks, and intestinal valves are presented. The species biology is discussed.
Analysis of dynamics for anomalies of the ice cover in the Okhotsk Sea in the period from 1882 to 2015
Authors: Pishchalnik Vladimir M. , Romanyuk Valery A. , Minervin Igor G. , Batuhtina Alevtina S.
Published: July 2021

The time-series for the ice cover dynamics in the Okhotsk Sea in the period from 1882 to 2015 are reconstructed on the base of shipboard, airborne, and satellite observations and measurements of the air temperature at the coastal meteorological stations. Abnormality of the ice conditions is estimated relative to the “climate norm” determined as the mean seasonal variation for the 1961-1990. Long-term variability of the ice cover is analyzed. Its regime shift with change of trend is revealed in the late 1970s - early 1980s that corresponds to the regime shift of the air temperature variability in the northern hemisphere.
On fishing of japanese sardine (Sardinops melanostictus)
Authors: Kudakaev Vasily V.
Published: July 2021

Japanese sardine resumes mass migrations to the Russian waters since 2014 that allows to restart domestic fishery of this species. Traditionally, Russian fishermen use purse seine for the sardine landing. Capacities of both purse seine and trawl fishing of japanese sardine are analyzed. There is concluded that the trawl fishing is more appropriate for the catch processing to fish flour.
Investigation of functional and technological properties of crushed milts
Authors: Dementeva Natalia V. , Bogdanov Valery D.
Published: July 2021

Fresh milts of salmon, cod, and herring possess high technological properties which are lowered in the processes of freezing and storage. The lowering is insignificant in the first month of storage but becomes more essential after two months of storage, in particular for the milt of cod. One of these properties is a high emulsifying ability. Stability of the emulsion systems with use of milt depends on the fish species, freshness of the raw materials, and preliminary thermal processing: the emulsions with milt of salmon have higher stability relative to the milts of other species and the unprocessed milt provides the highest stability of the emulsion systems. The milts could be used in emulsified products both as the emulsifiers and as functional ingredients that include proteins, nucleic acids, phospholipids, and polyunsaturated fatty acids.
Reproductive biology and embryonal development of pacific capelin Mallotus villosus catervarius from the Tauiskaya Bay (northern part of the Okhotsk Sea)
Authors: Yusupov Ravil R. , Santalova Maria Yu.
Published: July 2021

Reproductive biology of embryogeny and early ontogenesis is considered for pacific capelin Mallotus villosus catervarius (Pennant) from the Tauiskaya Bay in the northern Okhotsk Sea on the data of long-term sampling. The stages of periblastic sinus and Kupffer’s vesicle are described for the first time for the genus Mallotus. Results of the study allow to assume development of the embryonic vascular system of respiration for the capelin embryo. Tendency to the pacific capelin fecundity increasing is observed in the last five decades conditioned by its abundance lowering and consequent increase of the older fish percentage.
On occurrence of northern fur seals in the Tatar Strait (Japan Sea)
Authors: Kuzin Alexey E. , Maminov Michail K.
Published: July 2021

Results of observations on northern fur seals in the Tatar Strait are presented. The mammals were observed from the Nevelskoy Strait in the north to Cape Krilyon in the south.
Features of growth for Mytilus trossulus (Bivalvia: Mytilidae) in various conditions of habitat in the Tauiskaya Bay of the Okhotsk Sea
Authors: Zharnikov Vyacheslav S.
Published: July 2021

Biology of Mytilus trossulus is investigated in the Vesyolaya Cove, the Tauiskaya Bay on June 16 - September 20, 2011 within experimental studies of its cultivation ability in severe conditions of the northern Okhotsk Sea. In case of so called Spanish cultivation technology or its White Sea modification, the mussels grow to the commercial size (35 mm) in 3-4 seasons. To decrease this time to 1-2 seasons, the breeding technology is applied with the mussels collecting from the littoral substrate and their further breeding in hanged collectors. The mussels growth rate is evaluated both on the littoral substrate and in the collectors. The growth rate becomes lower after the mussels transfer from the littoral substrate to the hanged collectors but increases intensively after their transfer from the collectors to the littoral substrate, being higher that for the originally littoral mollusks. The growth rate dependence on size and age of the mussels is considered.
Отходы переработки дальневосточных голотурий как сырье для получения биологически активных добавок к пище
Authors: Ayushin Nickolay B. , Karaulova Ekatherina P. , Karlina Anastasia E. , Chepkasova Anna I. , Slutskaya Tatiana N.
Published: July 2021

Экспериментально установлены условия ферментативного гидролиза отходов, полученных при разделке промысловых голотурий, добываемых в морских акваториях российского Дальнего Востока. Показано, что гидролизаты содержат высокое количество тритерпеновых гликозидов, а также отличаются разнообразным составом макро- и микроэлементов, что позволяет позиционировать их как источник полезных минералов. Содержание селена настолько высоко, что 2-5 г лиофилизированного гидролизата фактически соответствуют рекомендованной суточной дозе этого элемента. Гидролизаты обладают высокой антиоксидантной активностью. Их органическая составляющая более чем на половину представлена биологически активными пептидами с молекулярной массой 2,5-5,0 кДа. Полученные результаты свидетельствуют о перспективности использования отходов переработки голотурий для получения биологически активных добавок широкого спектра действия.
Phylogeography of asian sockeye salmon Oncorhynchus nerka from the data on variability of mitochondrial SNP loci: analysis of scenarios for post-glacial expansion of the species over Asian Pacific coast
Authors: Khrustaleva Anastasia M.
Published: July 2021

Variability of three SNP loci allocated in the mitochondrial DNA ( One_CO1, One_Cytb_17, One_Cytb_26 ) is analyzed for sockeye salmon from its different habitats from Chukotka to Kuril Islands. Two basic haplotypes (GCC and GTT) are revealed in 20 samples of sockeye ( n = 33-100) from 15 lake-river systems. Their ratio is mostly equal, but GTT haplotype prevails in the populations from Kuril Islands (except Shumshu Island) and is absent in the sample from Commander Islands. This geographical pattern is presumably caused by historical-demographic events related to the species range formation in the middle-late Pleistocene: fragmentation of the areal and subsequent secondary contact between early diverged populations. Two scenarios are discussed, both with multiple expansions of the species to Asia during periods of oceanic transgression after Pleistocene glaciation. According to one of the scenarios, the GTT haplotype has more ancient origin somewhere on the mainland, whereas the GCC appeared much later in the central Kamchatka refugia. The second scenario presumes the origin of both haplotypes on Beringia Bridge where they diverged in the times of middle-Pleistocene (Wurm) glaciation.
Transfer of trace metals by trophic chain of plankton - filter-feeding bivalves in the brackish-water lagoon lakes on the Japan Sea coast
Authors: Lysenko Eugenia V. , Chernova Elena N.
Published: July 2021

Content of the metals Fe, Mn, Ni, Pb, Zn, Cd, and Cu was determined in the water, suspended matter, plankton organisms and bivalves collected in the brackish-water lagoon lakes on the coast of the Japan Sea in July 2011-2012, August 2013, and July 2014. The lakes are located in the sparsely populated area of eastern Sikhote-Alin including the Sikhote-Alin biosphere nature reserve. The content of Fe, Mn, Ni, and Pb has a tendency to decrease along the trophic chain that is conditioned by prevalence of their suspended forms over dissolved ones in the water and decreasing of the surface : weight ratio with size of living organisms. On the contrary, the content of Cu, Zn and Cd is rather stable along the food chain because of prevalence of their dissolved forms and low content in the suspended organic matter.
Feeding of masu salmon Oncorhynchus masou in the Okhotsk Sea in autumn
Authors: Efimkin Alexander Ya.
Published: July 2021

Feeding habits of masu salmon Oncorhynchus masou in the Okhotsk Sea is investigated. Its main prey in fall season is fish, amphipods, and euphausiids. However, the diet composition depends on the area: for masu with size of 30-40 cm it is mainly fish in the biostatistical districts 8 and 11 and zooplankton in other areas; besides, the zooplankton prey is replaced by fish for elder and larger salmons. The stomach fullness has significant circadian rhythm with one main maximum (70-700 ‱) and one minor peak. The main maximum was observed at 21 o’clock in 2002 but at 15 o’clock in 2006 and at 18 o’clock in 2009 and 2015 (local time).
Histological analysis of state of tissues in internal organs of black-backed shad Alosa kessleri kessleri
Authors: Grushko Maria P. , Fedorova Nadezhda N. , Aitimova Alina A.
Published: July 2021

Internal organs of black-backed shad are examined by histological analysis. Wide range of pathologies is found, which are supposedly caused by chronic environmental pollution. The pathologies of tissue and cellular levels have common features but various symptoms, as edema, hemorrhage, necrosis, inflammation, connective tissue proliferation, proliferative changes in the epithelium. The gills, liver; kidney, and intestines are the most sensitive to negative impacts of environments.
The Phyllospadix iwatensis community in the intertidal zone of the Far Eastern seas of Russia
Authors: Ivanova Maria B. , Tsurpalo Alexandra P.
Published: July 2021

The community of Phyllospadix iwatensis is studied using materials from expeditions of A.V. Zhirmunsky Institute of Marine Biology (National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences) and archive data (1949-2013) of the Laboratory of Chorology covering the species habitat area from Peter the Great Bay in the south to middle Kuril Islands in the north. The core of the community is identified. It has changing species composition; the changes correspond to geographical boundaries of the cenotic systems of Peter the Great Bay, the Lesser Kuril Islands, and Iturup Island. However, these boundaries do not coincide with the boundaries of the species-edificator habitat that embraces several cenotic systems. Spatial alterations of the cenotic systems are caused by landscape changes conditioned by general geomorphological situation and ecological conditions in the intertidal zone.
Collecting the spat of scallop Mizuhopecten yessoensis in conditions of associated settling of pacific mussel Mytilus trossulus
Authors: Gavrilova Galina S. , Kondratieva Elena S.
Published: July 2021

Collecting the spat of good quality and enough quantity, as the seeding material for commercial cultivation of scallop Mizuhopecten yessoensis Jay, 1857, is one of the main problems for aquaculture farms in Primorye. In the eastern Ussuri Bay, pacific mussel Mytilus trossulus Gould, 1850 is the dominant species which larvae settle on the systems designed for the scallop spat collecting. Its spat quantity in collectors exceeds the scallop spat number in 5-65 times, with the biomass in 3-140 times higher. The scallop spat survival dependence on abundance of the mussel spat is investigated but any correlation is not detected. However, general quality of the scallop spat in the farms in the Ussuri Bay is poor that could be a reason of its low survival on further stages of cultivation: mean size of the scallop spat here is close to the lower acceptable limit of the standard range (10-11 mm). Besides, food resources for the scallop spat could be limited in the years with high abundance of the mussel spat.
Submersion of the system «anchor-tightrope» of longline
Authors: Gabryuk Lyudmila A. , Gabryuk Viktor I.
Published: July 2021

A hydrodynamic problem for the longline system «anchor-tightrope» in resting fluid is formulated and solved on base of the theory of dynamics for systems with variable mass. The system of initial differential equations is solved by means of numerical methods using the software designed in MathCad-14 environment; parameters of the «anchor-tightrope» system in the process of submersion are calculated. Dependence of the time and velocity of submersion on type of anchor is analyzed taking into account the hydrodynamic forces dependence on Reynolds number. Influence of inertia force is determined. Cited results for dependence of the submersion time for fishing gear elements on depth are overviewed.
Coefficients for charge of raw material in processing of female red king crabs from the Barents Sea
Authors: Dvoretsky Alexander G. , Dvoretsky Vladimir G.
Published: July 2021

The raw material charge coefficients (RCC) are calculated for processing of female red king crabs from the coastal Barents Sea. The percentage outcome for limb clusters is 37.49 % (RCC 2.702), for meat - 19.63 % (RCC 5.163), and for merus - 6.25 % (RCC 16.304). The coefficients are lower as compared with the males of red king crab. These data let us to assess more accurately the number of crabs processed after illegal poaching landing.
Prospects of studies on the yeast flora of sturgeons for monitoring of their state in aquaculture
Authors: Terekhova Valeria E. , Bel’Kova Natalia L.
Published: July 2021

Seasonal changes in abundance and species composition of the yeast flora from organs of juvenile sturgeons were traced during their growing in the warm-water ponds of Luchegorsk Research Station of the Pacific Fish. Res. Centre (TINRO) in 2008-2009. The fungal community of the sturgeons was represented by whey, brewers, and wine yeasts, mostly with probiotic properties. Naganishia albida, Papiliotrema laurentii, Saccharomyces cerevisiae, Trichomonascus ciferrii , and fungi of the genus Candida were found in the intestines and gills of kaluga and siberian sturgeon juveniles, but they came from the water and are usual for microflora of cages for fish cultivation. Cryptococcus neoformans and Ogataea angusta were found in the water only. Rhodotorula mucilaginosa , Cystobasidium minuta and fungi of the genus Hanseniaspora were associated with the sturgeon organs. Generally the yeast heterotrophic microbiota in the cages showed inhibitory effect against mould and enterobacteria. Colonization of the sturgeon mucous membranes by yeasts had seasonal dynamics that definitely affected on local immunity of the juveniles. Complete elimination of the yeasts from the sturgeon mucous membranes should be considered as a predictor of worsening of their physiological state and anti-epizootic measures are necessary in this case.
Method for modeling of near-bottom longlines
Authors: Gabruk Victor I. , Gabruk Ludmila A. , Kudakaev Vasily V. , Belova Kseniia A.
Published: July 2021

Modeling technique for horizontal near-bottom longlines is presented. An example of this technique application for re-equipment of currently used bottom longlines to the near-bottom longlines is considered. Recommendations are given on choice of the buoys buoyancy, the anchor weight, and the weights for rigging of the near-bottom longline.