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Small-scale fishing experience fisherwomen of Yaguajay, Sancti Spíritus
No full textEl objetivo del trabajo es valorar las experiencias de tres mujeres residentes en el municipio Yaguajay, Sancti Spíritus, que pescan artesanalmente en el área protegida Parque Nacional Caguanes. Se realizaron tres entrevistas semiestructuradas que fueron grabadas, previo consentimiento informado. Se evidenció que las mujeres seleccionadas no solo han acompañado a sus esposos y familiares en la actividad pesquera, sino que también han sido partícipes de la pesca con fines recreativos. Ellas lo hacen ocasionalmente para su esparcimiento, pues tienen otras profesiones. Han vivido cerca del mar, pescan en embarcaciones y en la orilla, dominando las artes marineras. Son respetadas dentro del gremio de pescadores y se manifiestan relaciones de género equitativas, pues se integran de manera positiva a esta actividad productiva definida tradicionalmente como masculina.The goal of the paper is to evaluate the small-scale fishing experience of three fisherwomen operating within the boundaries of Caguanes National Park, Yaguajay, Sancti Spíritus. Semistructured in-depth interviews were carried out among three participants and recorded for qualitative content analysis. The main focus of interviews relied on the exploration of motivations behind fishing and topics including gender relations and equity among others. Results showed that women do not only accompany their husbands and family members when fishing, but are also actively engaged in recreational fishing. While maintaining a relatively low intensity of fishing activities (once a week or bimonthly trips), these women were high-skilled fishers who dominated seafaring and navigational crafts. As a consequence of their abilities, they are well respected within the local fishing association. The high level of integration exhibited by these women in a sector predominantly defined as masculine points to the existence of balanced gender relations. Findings from this study are thus highly relevant to those seeking to promote fishing among minority or undeserved sections of the population as well as incentivize the equal participation of genders within fishing operations.PublishedReferee
Phytoplankton traits and functional groups in the evaluation of functional redundancy and lake restoration in floodplains.
No full textBiological communities derive not from a random distribution of organisms but are the result of many processes that include abiotic factors, biotic interactions, and dispersion. The impact of human activities has affected the structure and functioning of ecological communities at an accelerated pace. The phytoplankton community represents a major primary producer of aquatic environments, therefore factors that interfere with its structure and dynamics can also impact other trophic levels in the ecosystem. In this perspective, functional redundancy was the central theme of the first paper, whose aim was to investigate the response of redundancy in phytoplankton communities to environmental factors, when measured for functional groups and functional traits. For this, six years of data collected quarterly (2008 to 2013) from two temperate and three subtropical lakes were used. Traits and groups were efficient to measure this attribute, however, the traits were more efficient when the structuring process of the communities was the environmental filtering. The functional traits most effectively explain the relationship between redundancy and environment. In the second paper, the influence of hydrodynamics, landscape and resources on the structure of the phytoplankton community during a floodplain lake restoration process was evaluated. As expected, factors related to hydrodynamics and resources (light and nutrients) were determinants for biovolume and density. The relative importance of landscape to community attributes increased over time of restoration. Cyanobacteria were dominant at the beginning of the restoration process, followed by phytoflagellates and diatoms. Aiming to disseminate science, the third article presents basic concepts of phytoplankton ecology and the main results related to the themes of the two scientific papers. In summary, the functional approach in phytoplankton ecology stands out as an important tool for the development of community ecology and for restoration and management of aquatic ecosystems projects.Comunidades biológicas não são combinações aleatórias de espécies e sim o resultado de diversos processos que incluem fatores abióticos, interações bióticas e dispersão. As ações antrópicas têm afetado a estrutura e funcionamento das comunidades ecológicas em ritmo acelerado. A comunidade fitoplanctônica representa o principal produtor primário dos ambientes aquáticos, portanto fatores que interferem na sua estrutura e dinâmica, também podem causar impactos nos demais níveis tróficos do ecossistema. Nessa perspectiva, a redundância funcional foi tema central da primeira abordagem, cujo objetivo foi investigar a resposta da redundância de comunidades fitoplanctônicas, diante de fatores ambientais, quando medida para grupos e traços funcionais. Para isso utilizou-se seis anos de dados coletados trimestralmente (2008 a 2013) referentes a dois lagos temperados e três subtropicais. Traços e grupos foram eficientes para medir esse atributo, entretanto os traços foram mais eficientes quando o processo estruturador das comunidades foi a filtragem ambiental. Os traços funcionais do fitoplâncton explicaram de maneira mais eficaz a relação entre redundância e ambiente. Na segunda abordagem, avaliou-se a influência da hidrodinâmica, paisagem e recursos sob a estrutura da comunidade fitoplanctônica durante um processo de restauração de um lago de planície de inundação. Como esperado, os fatores relacionados a hidrodinâmica e aos recursos (luz e nutrientes) foram determinantes para o biovolume e densidade. A importância relativa da paisagem para os atributos da comunidade aumentou ao longo do tempo de restauração. Cianobactérias foram dominantes no início da restauração, seguidas de fitoflagelados e diatomáceas. Com o objetivo de divulgar a ciência, a terceira abordagem apresenta conceitos básicos do fitoplâncton e agrupa os principais resultados referentes a redundância funcional e restauração lacustre. Enfatiza-se o uso de traços e grupos funcionais do fitoplâncton como uma importante ferramenta para o desenvolvimento da ecologia de comunidades e para projetos de restauração e manejo dos ecossistemas aquáticos.Ph
Обоснование рационального метода сушки гранул в кипящем слое и гидродинамического режима их взаимодействия с ожижающим агентом
No full textGluten is produced from wheat grains and is used in the food industry as an improver in flour baking properties. On the basis of a comparative analysis of the methods of dehydration of frozen granules of wheat gluten with a surface dry crust, a rational method of drying them in a fluidized bed has been selected. In the process of calculating units with a fluidized bed, its hydrodynamic parameters have been determined: loss of the pressure of the fluidizing agent; the speed at the transition of the bed from the state of rest to the pseudo-boiling mode; layer porosity; the rate of entrainment of particles in unrestricted conditions roughly corresponding to the rate of soaring, at which a single particle is in equilibrium in the gas flow. During the dewatering operation, the rate of entrainment of the granules varies; therefore, it is advisable to use the passing fluidization mode depending on the decrease in their moisture content. In the variant of the active hydrodynamic regime in the drying unit, the dehydration procedure is intensified without a noticeable decrease in the economic efficiency of its functioning and high quality indicators of the finished product with the given final moisture are provided, which is due to the specific conditions of contact of the granules with the coolant. For granules with a moisture content of 0.19 kg/kg, the values of hydrodynamic characteristics have been determined: the area of critical pseudo-boiling rates is 4.1–5.5 m/s; the carryover rate of the fines is 12.5–14.5 m/s. As a result of the study, the choice has been substantiated in favor of drying the studied granules in a fluidized bed due to the prevalence of its advantages over the dehydration of the object in drum dryers.Клейковина вырабатывается из пшеничного зерна и используется в пищевой промышленности в качестве улучшителя пекарных параметров муки. На основе сравнительного анализа способов обезвоживания замороженных гранул пшеничной клейковины с поверхностной сухой корочкой выбран рациональный способ их сушки в кипящем слое. В процессе расчетов агрегатов с псевдоожиженным слоем определены его гидродинамические показатели: потеря давления ожижающего агента; скорость при переходе слоя из состояния покоя в режим псевдокипения; порозность слоя; скорость уноса частиц в нестесненных условиях, ориентировочно соответствующая скорости витания, при которой единичная частица находится в равновесии в газовом потоке. При операции обезвоживания скорость уноса гранул варьируется, поэтому целесообразно применять режим проходящего псевдоожижения в зависимости от снижения их влажности. В варианте активного гидродинамического режима в агрегате для сушки интенсифицируется процедура обезвоживания без заметного уменьшения экономической эффективности его функционирования и обеспечиваются высокие качественные показатели готовой продукции с заданной итоговой влажностью, что обусловлено специфическими условиями контакта гранул с теплоносителем. Для гранул влажностью 0,19 кг/кг определены величины гидродинамических характеристик: ареал критических скоростей псевдокипения составляет 4,1–5,5 м/с; скорость уноса мелкой фракции – 12,5–14,5 м/с. В результате исследования обоснован выбор в пользу сушки исследуемых гранул в кипящем слое вследствие превалирования его достоинств над обезвоживанием объекта в барабанных сушильных установках.PublishedReferee
Đánh giá không gian phát tán của san hô tạo rạn Việt Nam dưới ảnh hưởng của dòng chảy Biển Đông
No full textRecognizing the flow regime in the breeding season is the dominant factor for the marine biota, a flow diagram of the Bien Dong (East Vietnam Sea) in the transitional season has been established to examine the relationship between the current and its distribution and diversity of reef-forming coral in the sea of Vietnam. The data source for modeling the current regime is updated from the Climate Forecast System Reanalysis of the National Center for Environmental Prediction (NCEP CFSR) and exploited from the HYCOM + NCODA Global 1/12.5 database for the period 1993-2012 and of HYCOM + NCODA Global 1/12o Analysis for the period from 2013 to 2020. Along with that, the finite element method (FEM) was used to build a 3D hydrodynamic model. Based on the constructed flow diagram, the dispersal capacity of coral larvae in each sea area is assessed to compare with previous observations on the species diversity of reef-forming corals. The finding includes: (1) the Gulf of Tonkin and Gulf of Thailand exhibit poor exchange and lower diversity than the continental shelf and coastal waters of Vietnam; (2) Cape Varella is a vital boundary dividing the East Vietnam Sea, forming the most diverse areas in good exchange conditions of water bodies in the south of the 13°N parallel, including the Truong Sa (Spratly) Islands. This system can be considered as part of the Coral Triangle in the Bien Dong.PublishedReferee
Изотопные характеристики серы сульфидов Хибинского и Ловозерского массивов (Кольская щелочная провинция, Фенноскандинавский щит)
No full textThe sulfur isotope geochemistry of the Khibina and Lovozero agpaitic massifs provides an opportunity to understand the role of plume-lithosphere interaction processes responsible for the Paleozoic alkaline igneous activity in the north-eastern part of the Fennoscandian Shield. The stable sulfur isotope δ 34S analysis using triple collector isotope ratio mass spectrometer (IRMS) has been carried out on the pentlandite, chalcopyrite and pyrite from nepheline syenites. The δ 34S values for pentlandite from Khibina rocks range from +0.69 to +2.06 ‰ relative to the Vienna Canyon Diablo Troillite standard (VCDT), and the pyrite has significantly higher δ 34S values up to +4.92 ‰ VCDT. The pentlandite from the Lovozero samples has value +1.48 ‰ VCDT, δ 34S values of chalcopyrite is +2.85 ‰ VCDT. The maximum positive δ 34S values are obtained for Lovozero pyrite, which vary from +5.41 to +6.30 ‰ VCDT. Comparison of sulfur-geochemical features of Khibina and Lovozero nepheline syenite with δ 34S data for the carbonatites from the Khibina, Sallanlatvi, Seblyavr, Vuoriyarvi, Salmagora and Kovdor massifs show later carbonatite formation relatively to associated alkaline rocks. Geochemical sulfur isotope δ 34S investigations emphasizes that parental magmas of the Khibina and Lovozero alkaline massifs were derived from a metasomatized subcontinental lithospheric mantle (SCLM). We suggest that high-?34S signature on the SCLM (δ 34S of +1 to +6 ‰ VCDT) can be explained by subduction of the high-δ 34S Archaean crust.Геохимия изотопов серы Хибинского и Ловозерского агпаитовых массивов дает возможность понять роль плюм-литосферных процессов, ответственных за палеозойскую щелочную магматическую активность в северо-восточной части Фенноскандинавского щита. Изотопный состав серы (δ 34S) получен для пентландита, халькопирита и пирита из нефелиновых сиенитов с использованием масс-спектрометра с тройным коллектором (IRMS). Значения δ 34S пентландита из пород Хибинского массива варьируют от +0,69 до +2,06 ‰ относительно стандарта Вена-Каньон-Дьябло-Троилит (VCDT); значительно выше значения для пирита (+ 4,92 ‰ VCDT). Ловозерский пентландит имеет значение δ 34S, равное +1,48 ‰ VCDT; δ 34S для халькопирита составляет +2,85 ‰ VCDT. Максимально положительные значения δ 34S для сульфидов Ловозерского массива получены для пирита (от +5,41 до +6,30 ‰ VCDT). Сравнение полученных данных с данными по изотопии серы для карбонатитов Хибин, Салланлатви, Себлъявра, Вуориярви, Салмагоры и Ковдора указывает на более позднее образование карбонатитов относительно связанных с ними щелочных пород. Геохимические исследования изотопов серы показывают, что первичным магматическим источником Хибинского и Ловозерского щелочных массивов является метасоматизированная субконтинентальная литосферная мантия (SCLM). Сделано предположение, что высокие значения δ 34S для SCLM (от +1 до +6 ‰ VCDT) обусловлены субдукцией архейской коры, обогащенной тяжелым 34S изотопом серы.PublishedReferee
Proporción de madurez del tiburón Carcharhinus falciformis (Müller y Henle, 1839) (Chondrichthyes: Carcharhinidae), en el norte de La Habana, Cuba
No full textEl conocimiento de la edad y la talla en que los tiburones alcanzan la madurez sexual es muy importante para la administración y la toma de decisiones sobre el aprovechamiento óptimo de recursos marinos explotados. Carcharhinus falciformis es una especie amenazada, por lo que extraer ejemplares que no han alcanzado la madurez, atenta contra el mantenimiento y recuperación de sus poblaciones. En este estudio se determinó la proporción de madurez por talla para sexos combinados (hembras y machos) de dicha especie. Los muestreos se realizaron en la Base de pesca de Cojímar, al noreste de La Habana, en el período (2011-2020). Se registraron un total de 186 ejemplares de C. falciformis en las capturas. La mayor parte de los ejemplares se hallaron entre los 100 y 140 cm LT, considerándolos juveniles, lo que sugiere que la población de esta especie al norte de La Habana está compuesta, en su mayoría, por individuos inmaduros. Las hembras dominaron la proporción por sexo esperada de 1:1 de la totalidad de las capturas (hembra: macho = 1.9:1; X2 = 14.8, P = 0.0001), lo cual puede influir en el reclutamiento y futuro de la población. Los parámetros de la función logística para describir la proporción de madurez de C. falciformis fueron LT50% = 207.45 cm (IC95%: 193.61-221.3 cm) y Φ = 10.746 (IC95%: 5.435-21.246). Los parámetros presentados aquí, contribuyen a la evaluación de poblaciones y para implementar medidas de gestión para la conservación global de estas especies transfronterizas de tiburones pelágicos altamente vulnerables.Knowledge of age and size at which sharks reach sexual maturity, is very important for management and decision making for optimal use of exploited marine resources. Carcharhinus falciformis is a threatened species, that is why extracting specimens that have not reached maturity, threatens maintenance and recovery of their populations. It was determined by this study maturity by size ratio for combined sexes (female and male) of this species. Samplings were carried out at Cojímar fishing base, at northeast of Havana, between 2011 and 2020. A total of 186 specimens of C. falciformis were registered in the catches. Most of the specimens were found between 100 cm and 140 cm TL, they were considered juveniles, which suggests that population of this species at north of Havana is composed in its majority by immature individuals. Females won the expected 1:1 sex ratio from the total of catches (female: male = 1.9:1; X2 = 14.8, P = 0.0001), which might influence recruitment and future of the population. Logistic function parameters for describing maturity ratio of C. falciformis were TL50% = 207.45 cm (CI95%: 193.61-221.3 cm) and Φ = 10.746 (CI95%: 5.435-21.246). Parameters presented in this study contribute to the stock assessment and to implement management measures for the global conservation of these highly vulnerable transboundary pelagic shark species.Bachelor
Characterization of material culture of the riverine contexts
No full textEste documento hace parte de un conjunto de conferencias que se presentaron en el III Seminario Nacional de Patrimonio Cultural Marítimo organizado por la Fundación Museo Naval del Caribe Colombiano y otras instituciones. En él se trataron diversas temáticas vinculadas a los oficios y saberes en contextos marítimos y rivereños. La presente investigación se presentó en la mesa de perspectivas y desafíos de jóvenes, donde se trataron temas como la pesca, la construcción naval y la habitabilidad en relación con los dos contextos mencionados. Este trabajo hace parte de una investigación que se está desarrollando en el grupo de estudio de Territorios Líquidos de la Universidad Externado de Colombia alrededor de la cultura material de los barcos a vapor que navegaron el río Magdalena en los siglos XIX y XX. A partir de un análisis de fuentes históricas se realizó esta primera aproximación que tiene como objetivo hacer una caracterización del fenómeno de la navegación fluvial a través del conocimiento de los barcos, sus tripulantes y las actividades que en ellos se desarrollaban.This document is part of a group of conferences presented in the “III Seminario Nacional de Patrimonio Cultural Marítimo”, organized by the “Fundación Museo Naval del Caribe Colombiano” and other institutions. In this seminar diverse themes related to work and knowledge in maritime and riverine contexts were talked about. The following investigation was presented on a table regarding diverse thematics such as fishing, naval construction and the skill related to the previously mentioned activities. This project is part of an investigation that is being developed in the study group "Territorios Líquidos" of the Universidad Externado de Colombia, regarding the material culture of steamships that sailed around the Magdalena River during the XIX and XX centuries by the means of an analysis made using written sources. This first approximation has the objective of characterizing the phenomena of fluvial navegation with knowing the ships, their crews and the activities that were developed on these spaces.PublishedNot Know
Design of an oceanographic sampling network for the Malpelo Fauna and Flora Sanctuary, Pacific of Colombia
No full textCon el objetivo de generar insumos para el manejo del Santuario de Flora y Fauna Malpelo, la Dirección Territorial Pacífico de Parques Nacionales Naturales de Colombia, inició en 2006 un monitoreo de condiciones oceanográficas en el área. En la actualidad este monitoreo cuenta con una malla de muestreo de solo seis estaciones ubicadas a 0,93 km (0,5 millas náuticas) y 1,85 km (1 milla náutica) desde la isla, por lo que es poco eficiente debido a la reducida distancia entre estaciones e insuficiente dada la gran extensión del Santuario. Por lo tanto, se diseñó una malla de muestreo con base en datos de temperatura superficial del mar (TSM) tomados in situ, derivados del sensor remoto MODIS-Aqua. Se analizó la estructura de autocorrelación espacial a través de una función de semivarianza. La decisión para elegir la mejor malla de muestreo entre los diferentes tamaños, fue basada en la disimilitud entre estaciones asociada al modelo de semivarianza, en la varianza del error de predicción, en el patrón de corrientes marinas predominante durante el ciclo anual, y en aspectos logísticos relacionados con las limitantes de desplazamiento de las embarcaciones que realizan los monitoreos oceanográficos en el SFF Malpelo. Como resultado de considerar estas variables, se obtuvo una malla de muestreo con estaciones cada 7,41 km (4 millas náuticas) compuesta por ocho estaciones nuevas y las seis de la malla de muestreo histórica.In order to generate inputs for the management of the Sanctuary, the Pacific Territorial Directorate of National Natural Parks began in 2006 a monitoring of oceanographic conditions in the area. Currently, this monitoring has a sampling network of only six stations located 0.93 km (0.5 nm) and 1.85 km (1 nm) from the island, so it is not efficient due to the reduced distance between stations, and insufficient given the large extension of the Sanctuary. Therefore, a sampling network was designed based on Sea Surface Temperature (TSM) data taken in situ and derived from the Modis-Aqua remote sensor. The spatial autocorrelation structure was analyzed through a semi-variance function. The decision to choose the best sampling network among the different sizes was based on the dissimilarity between stations associated with the semi-variance model, on the variance of the prediction error, on the predominant pattern of marine currents during the annual cycle, and on aspects logistics related to the movement limitations of the vessels that carry out oceanographic monitoring in the SFF Malpelo. As a result of considering these variables, a sampling network was obtained with stations every 7.41 km (4 nm) , composed of eight new stations and six of the historical sampling network.PublishedReferee
Rooks fish pass at Garstang Weir in River Wyre
No full textRooks fish pass at Garstang Weir in the River Wyre, North West England, UK. This photo shows pollution in River Lune in July 1949. This photo is part of a Photo Album that includes pictures from 1935 to 1954.Environment Agency Archives North WestImage taken from Historic Photo Collection containing images on Fisheries and Fish pass construction from 1935 to 1954. The album, originally owned by the Environment Agency North West, is now held by the Freshwater Biological Association
Химическая и ферментативная деструкция хондроитина сульфата из северного ската
No full textDue to its biocompatibility with human and animal tissues, low toxicity, and biodegradability, chondroitin sulfate (CS) is of great interest for medicine. Since CS is used as a pharmaceutical preparation, its molecular weight and solubility determine the possibilities of its use. This work presents the results of studying the chemical and enzymatic destruction of CS macromolecules and its effect on the molecular weight, solubility and crystallinity degree of the polysaccharide. CS was obtained from the cartilaginous tissue of the Arctic skate (Amblyraja hyperborea). At the stage of cartilage tissue fermentolysis, the enzymes pancreatin, hepatopancreatin and protosubtil were used. The obtained CS samples were identified by IR spectroscopy. Enzymatic destruction of glycosidic bonds in cholesterol macromolecules was carried out with a 1 % solution of the enzyme hepatopancreatin, chemical destruction with hydrogen peroxide and hydrochloric acid. The CS content in the samples was determined by the Dische method. The chemical composition of CS samples was evaluated by standard methods. The average molecular weight (MW) was determined using high performance liquid chromatography and the nephelometric method. The crystallinity degree (CD) was determined by graphical processing of diffraction patterns obtained by X-ray phase analysis of CS samples. It was found that under the action of hepatopancreatin and hydrogen peroxide, deep destruction of chondroitin sulfate occurs, to the formation of low molecular weight and oligomeric fragments. Under conditions of acid destruction in 0.5 N HCl for 20 min the MW of chondroitin sulfate is reduced by 10 % compared to the initial one. Acid destruction causes a significant decrease in the CD of the CS samples. For CS samples not degraded in acid, the solubility in distilled water increases with decreasing MW and CD. The solubility of CS after acid destruction in the range of pH = 5–9 units is 99.0 ± 0.5 %. This high solubility is most likely explained by the significant content of the amorphous phase in the samples.Благодаря биосовместимости с тканями человека и животных, низкой токсичности, биодеградируемости хондроитина сульфат (ХС) представляет большой интерес для медицины. Поскольку ХС используется как фармацевтический препарат, то величина его молекулярной массы и растворимость определяют возможности его применения. Приведены результаты изучения химической и ферментативной деструкции макромолекул ХС и ее влияние на молекулярную массу, растворимость и степень кристалличности полисахарида. ХС получали из хрящевой ткани северного ската (Amblyraja hyperborea). На стадии ферментолиза хрящевой ткани использовали ферменты панкреатин, гепатопанкреатин и протосубтилин. Идентификацию полученных образцов ХС выполняли методом ИК-спектроскопии. Ферментативную деструкцию гликозидных связей в макромолекулах ХС проводили 1%-м раствором фермента гепатопанкреатина, химическую деструкцию – перекисью водорода и хлороводородной кислотой. Содержание ХС в образцах определяли методом Дише. Химический состав образцов ХС оценивали стандартными методами. Среднемассовую молекулярную массу (ММ) определяли с помощью высокоэффективной жидкостной хроматографии и нефелометрическим методом; степень кристалличности (СК) – графической обработкой дифрактограмм, полученных рентгенофазовым анализом образцов ХС. Установлено, что под действием гепатопанкреатина и перекиси водорода происходит глубокая деструкция хондроитина сульфата, до образования низкомолекулярных и олигомерных фрагментов. В условиях кислотной деструкции в 0,5 н HCl в течение 20 мин ММ хондроитина сульфата снижается на 10 % по сравнению с исходной. Кислотная деструкция вызывает значительное уменьшение СК образцов ХС. Для не деструктированных в кислоте образцов ХС растворимость в дистиллированной воде увеличивается с уменьшением ММ и СК. Растворимость ХС после кислотной деструкции в диапазоне рН = 5–9 единиц составляет 99,0 ± 0,5 %. Высокая растворимость, по всей видимости, объясняется значительным содержанием в образцах аморфной фазы.PublishedReferee