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Perceptions of fishers to sea turtle bycatch,illegal capture and consumption in the San Ignacio-Navachiste-Macapule lagoon complex,Gulf of California,Mexico

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Integrative Zoology 2014年第1期9卷 70-84页

作者： Myrna E.AGUILAR-GONZÁLEZ Antonio LUNA-GONZÁLEZ Alonso AGUIRRE alan a.zavala-norzagaray Manuel MUNDO-OCAMPO Héctor A.GONZÁLEZ-OCAMPO National Polytechnic Institute(IPN) CIIDIR-IPNUNIDAD SINALOAJuan de Dios Batiz ParedesGuasaveSinaloaMexico Department of Environmental Science and Policy George Mason UniversityFront RoyalVAUSA

In this study, 10% of all registered fishermen in the coastal towns of Navachiste in Sinaloa, in northwestern Mexico, answered a survey designed to collect data on their perceptions of the following topics: the impact of turtle meat consumption;human health;bycatch;illegal turtle fishing;the illegal sea turtle market;the lo-cal economy;pollution;environmental education;the success of protective legislation;and sea turtle-based ec-otourism. Perceptions were analyzed using the fuzzy logic method through classification into 5 fuzzy member-ship sets: VL, very low;L, low;M, moderate;H, high;VH, very high. The 9 topics generated decision areas upon applying fuzzy inference that revealed the membership level of the answers in each fuzzy set. The eco-nomic potential of sea turtle-based ecotourism and the economic profitability of the illegal turtle meat market were perceived as VL. Conservation legislation was perceived as H, although inefficiently applied due to cor-ruption. Ecotourism and impacts on sea turtles were perceived as VL, because they were deemed unprofitable activities at the individual and community levels. Environmental education was perceived as L, because it cen-ters on nesting, hatching and releasing turtles and is directed at elementary and middle-school students. While fishers perceive a serious negative impact of fishing activities on sea turtles in the San Ignacio-Navachiste- Macapule area, they do not see themselves individually as part of the problem. Achieving sea turtle conserva-tion in this region requires: suitable ecotourism infrastructure, government investments in promotion, and stud-ies to estimate the minimum number of tourists needed to assure profitability.

关键词： environmental impact assessment fishers’perceptions of impact impact on coastal fisheries sea turtle conservation

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Hyperpycnal (over density) flows and deposits

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Journal of Palaeogeography 2020年第3期9卷 267-287页

作者： Carlos zavala Departamento de Geologia Universidad Nacional del SurSan Juan 6708000 Bahia BlancaArgentina GCS Argentina 5RL Molina Campos 1508000 Bahia BlancaArgentina

A hyperpycnal flow forms when a relatively dense land-derived gravity flow enters into a marine or lacustrine water reservoir. As a consequence of its excess of density, the incoming flow plunges in coastal areas, generating a highly dynamic and often long-lived dense underflow. Depending on the characteristics of the parent flow(flow duration and flow rheology) and basin salinity, the resulting deposits(hyperpycnites) can be very *** to flow duration, land-derived gravity flows can be classified into short-lived or long-lived flows. Shortlived gravity flows last for minutes or hours, and are mostly related to small mountainous river discharges, alluvial fans, collapse of natural dams, landslides, volcanic eruptions, j?kulhlaups, etc. Long-lived gravity flows last for days,weeks or even months, and are mostly associated with medium-to large-size river *** the rheology of the incoming flow, hyperpycnal flows can be initiated by non-Newtonian(cohesive debris flows), Newtonian supercritical(lahars, hyperconcentrated flows, and concentrated flows) or Newtonian subcritical flows(pebbly, sandy or muddy sediment-laden turbulent flows). Once plunged, non-Newtonian and Newtonian supercritical flows require steep slopes to accelerate, allow the incorporation of ambient water and develop flow transformations in order to evolve into a turbidity current and travel further basinward. Their resulting deposits are difficult to differentiate from those related to intrabasinal turbidites. On the contrary, long-lived Newtonian subcritical flows are capable of transferring huge volumes of sediment, freshwater and organic matter far from the coast even along gentle or flat slopes. In marine settings, the buoyant effect of interstitial freshwater in pebbly and sandy hyperpycnal flows can result in lofting due to flow density reversal. Since the excess of density in muddy hyperpycnal flows is provided by silt-clay sediments in turbulent suspension, lofting

关键词： Hyperpycnal flows Hyperpycnites Turbidites Sediment gravity flows

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The new knowledge is written on sedimentary rocks——a comment on Shanmugam’s paper “the hyperpycnite problem”

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Journal of Palaeogeography 2019年第3期8卷 306-313页

作者： Carlos zavala Departamento de Geología Universidad Nacional del Sur GCS Argentina SRL

In a recent contribution G. Shanmugam (2018) discusses and neglects the importance of hyperpycnal flows and hyperpycnites for the understanding of some sediment gravity flow deposits. For him, the hyperpycnal flow paradigm is strictly based on experimental and theoretical concepts, without the supporting empirical data from modern depositional systems. In this discussion I will demonstrate that G. Shanmugam overlooks growing evidences that support the importance of hyperpycnal flows in the accumulation of a huge volume of fossil clastic sediments. Sustained hyperpycnal flows also provide a rational explanation for the origin of well sorted fine-grained massive sandstones with floating clasts, a deposit often wrongly related to sandy debris flows.

关键词： Hyperpycnites Turbidites Sediment gravity flows

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A case study on how astronomical cycles affect the organic carbon accumulation

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Journal of Palaeogeography 2023年第4期12卷 637-651页

作者： Yang Li Ren-Chao Yang Carlos zavala Liang Dong Valentin Trobbiani Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071Shandong ProvinceChina Geology Department Universidad Nacional del SurBahía Blanca 8000Argentina Geología de Cuencas Sedimentarias(GCS)Argentina Bahía Blanca 8000Argentina

The paleoclimate change impacts the sedimentary environment and process,which in turn control the accumulation of organic *** studies have shown that the paleoclimate is controlled by astronomical ***,understanding how these cycles impact the accumulation of organic carbon is a critical question that requires in-depth *** studies have shown that Milankovitch cycle can be revealed from the sediments of the 7^(th)Oil Member(Chang 7 Member for short)of the Triassic Yanchang Formation in the southern Ordos Basin,suggesting that the deposition was controlled by astronomically-forced climate *** on previous research,this study collected natural gamma(GR)data of Chang 7 Member from the N36 Well to further analyze astronomical cycles,combined with X-ray fluorescence(XRF)analysis and total organic carbon(TOC)tests,to reconstruct the paleoenvironment and analyze the organic matter enrichment *** results of this contribution show that,paleoclimate,paleo-redox conditions,paleo-water level,paleo-productivity and sediment accumulation rate(SAR)collectively controlled the enrichment of organic ***,this study identified the presence of eccentricity,obliquity,precession,and the 1.2 Myr long obliquity cycle in the Chang 7 *** cycles controlled the paleoenvironmental changes at different timescales and influenced the enrichment of organic matter,which has implications for subsequent energy exploration.

关键词： Cyclostratigraphy Milankovitch cycle Organic matter enrichment Paleoenvironmental Ordos Basin Chang 7 Member

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Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

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Asian Pacific Journal of Tropical Biomedicine 2015年第4期5卷 287-291页

作者： Rosario Ruiz-Guerrero Mario Alberto Rodríguez-Pérez Mariano norzagaray-Campos CIITEC-IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco Centro de Biotecnología Genómica-IPN Blvd. Del Maestro S/N Colonia Narciso Mendoza CIIDIR-IPN-Sinaloa Bulevar Juan de Dios Bátiz Paredes No 250 Colonia San Joachin. Guasave

Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and Pseudosmodingium perniciosum(P. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue ***: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(LC50 values ranged between 20 and 890 μg/mL). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of P. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(LC50 values were80, 50, and 20 μg/mL, respectively), thus making them potential candidates as *** are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue ***: A. mexicana and P. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

关键词： Aedes aegypti Dengue Larvicidal activity Plant organic extracts

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Deltas:a new classification expanding Bates's concepts

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Journal of Palaeogeography 2021年第3期10卷 341-355页

作者： Carlos zavala Mariano Arcuri Mariano Di Meglio Agustin Zorzano German Otharan Ainara Irastorza Antonela Torresi Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia BlancaArgentina GCS Argentina SRL Molina Campos 1508000 Bahia BlancaArgentina Consejo Nacional de Investigaciones Científicas y Tecnicas (CONICET)Buenos AiresArgentina

Deltas constitute complex depositional systems formed when a land-derived gravity-flow(carrying water and sediments) discharges into a marine or lacustrine standing body of water. However, the complexity of deltaic sedimentary environments has been oversimplified by geoscientists over the years, considering just littoral deltas as the unique possible type of delta in natural systems. Nevertheless, a rational analysis suggests that deltas can be much more complex. In fact, the characteristics of deltaic deposits will depend on a complex interplay between the bulk density of the incoming flow and the salinity of the receiving water body. This paper explores the natural conditions of deltaic sedimentation according to different density contrasts. The rational analysis of deltaic systems allows to recognize three main fields for deltaic sedimentation, corresponding to(1) hypopycnal(2) homopycnal and(3) hyperpycnal delta settings. The hypopycnal delta field represents the situation when the bulk density of the incoming flow is lower than the density of the water in the basin. According to the salinity of the receiving water body, three different types of hypopycnal littoral deltas are recognized: hypersaline littoral deltas(HSLD), marine littoral deltas(MLD), and brackish littoral deltas(BLD). The basin salinity will determine the capacity of the delta for producing effective buoyant plumes, and consequently the characteristics and extension of prodelta *** littoral deltas(HOLD) form when the density of the incoming flow is roughly similar to the density of the water in the receiving basin. This situation is typical of clean bedload-dominated rivers entering freshwater lakes. Delta front deposits are dominated by sediment avalanches. Typical fallout prodelta deposits are absent or poorly developed since no buoyant plumes are generated. Hyperpycnal deltas form when the bulk density of the incoming flow is higher than the density of the water in the receivi

关键词： Deltas Hyperpycnal flows Homopycnal flows Hypopycnal flows Hyperpycnites Turbidites Sediment gravity flows Gravity flows

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High-frequency lacustrine sequence stratigraphy of clastic lakes:lessons from ancient successions

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Journal of Palaeogeography 2024年第4期13卷 621-645页

作者： Carlos zavala Hua-Qing Liu Xiang-Bo Li Valentin Trobbiani Yang Li Mariano Arcuri Agustin Zorzano Departamento de Geología Universidad Nacional del Sur(UNS)Bahía BlancaBuenos AiresArgentina GCS Consulting Services Bahía Blanca Buenos AiresArgentina Research Institute of Petroleum Exploration&Development-Northwest PetroChinaLanzhou 730020China Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Buenos AiresArgentina Shandong University of Science and Technology Qingdao 266590Shandong ProvinceChina

Sequence stratigraphic concepts and methods provide novel tools for performing stratigraphic analysis,allowing us to improve our understanding of depositional models and basin *** controls and depositional elements(e.g.,surfaces,systems tracts,parasequences,etc.)recognized in conventional sequence stratigraphy are designed for marine-related *** contrast,the sequence stratigraphy of lacustrine successions is much more complex and poorly understood,because it is not driven by sea-level changes,but by a complex interaction between tectonics and high-frequency climatic *** comprehensive analysis of the water balance of lacustrine systems allows the recognition of three types of lake conditions:Underfilled,balanced-fill and overfilled *** the lake conditions in ancient successions is fundamental for unraveling lacustrine sequence stratigraphy,since these conditions effectively control water salinity,internal stacking pattern and the characteristics of systems *** lakes are hydrologically closed lakes,and consequently,the lake-level can highly fluctuate,driven by high-frequency wet-dry climatic *** wet periods,rivers supply water and sediments,resulting in fining-and thinning-upward elementary depositional sequences(EDS's)accumulated during the transgressive systems tract(TST).In contrast,dry periods are characterized by a relative lake-level fall with the subaerial exposure of lake margin areas during the regressive systems tract(RST).Lake water salinity can fluctuate from brackish to ***-fill lakes are partially closed lakes,and consequently,they have characteristics of both underfilled and overfilled *** the TST,the lake is in underfilled condition,and consequently,the introduction of water and sediment will accumulate a fining-upward interval until reaching the spill point during the maximum *** RST is accumulated under an overfilled lake condition,with coarseningupwa

关键词： Lacustrine sequence stratigraphy Underfilled lakes Balanced-fill lakes Overfilled lakes Forced transgression Forced regression

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A novel method for determination of lethal radius for high-explosive artillery projectiles

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Defence Technology（防务技术） 2021年第4期17卷 1217-1233页

作者： alan Catovic Elvedin Kljuno Mechanical Engineering Faculty(Defense Technology Department) University of SarajevoSarajevoBosnia and Herzegovina Mechanical Engineering Faculty University of SarajevoSarajevoBosnia and Herzegovina

A new model has been defined that enables the estimation of the lethal radius(radius of efficiency)of HE(High Explosive)artillery projectiles against human *** model is made of several modules:CAD(Computer Aided Design)modeling,fragment mass distribution estimation,fragment initial velocity prediction,fragment trajectory calculation,effective fragment density estimation,and high explosive projectile lethal radius *** results were compared with the experimental results obtained based on tests in the arena used in our country,and the agreement of the results was *** model can be used in any terminal-ballistics scenario for high explosive projectiles since it is general,parametric,fast and relatively easy to implement.

关键词： High explosive projectiles Lethal radius Fragments Modeling

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Phylogenetic positions of two marine ciliates, Metanophrys similis and Pseudocohnilembus hargisi (Protozoa, Ciliophora,Scuticociliatia), inferred from complete small subunit rRNA gene sequences

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Progress in Natural Science:Materials International 2006年第4期16卷 373-378页

作者： alan WARREN Department of Zoology The Natural History Museum Cromwell Road London SW7 5BD UK

The small subunit rRNA (SSrRNA) gene was sequenced for two marine scuticociliates Metanophrys similis and Pseudocohnilembus hargisi. The results show that this gene comprises 1763 and 1753 nucleotides in the two marine ciliates respectively. Metanophrys similis is phylogenetically closely related to the clade containing Mesanophrys carcini and Anophyroides haemophila, which branches basally to other species within the order Philasterida. Pseudocohnilembus hargisi groups with its congener, P. marinus, with strong bootstrap support. Paranophrys magna groups with the clade including Cohnilembus and Uronema, representing a sister clade to that containing the two Pseudocohnilembus species.

关键词： phytogeny protozoa scuticociliate Metanophrys similis Pseudocohnilembus hargisi.

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Estimation of projected surface area of irregularly shaped fragments

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Defence Technology（防务技术） 2019年第2期15卷 198-209页

作者： Elvedin Kljuno alan Catovic Mechanical Engineering Faculty University of Sarajevo

The essence and the main contribution of this paper are consisted of the suggested novel method for estimation of a projected surface area of an irregularly shaped fragment, which represents a significant step toward a new method of an aerodynamic force estimation of a fragment motion through a resistive medium. The suggested method is to use a tri-axial ellipsoid that has a continuous surface(given as a mathematical function) to approximate an irregularly shaped fragment so that the fragment trajectory can be estimated faster taking into consideration that the aerodynamic force is proportional to a projected surface area of the *** their motion, fragments can take any orientation relative to the velocity vector and aerodynamic force is proportional to a projected surface area of fragment perpendicular to the velocity vector,so it is necessary to have a method for correct estimation of the projected area in an arbitrary direction relatively to the *** model was validated with analytical and CAD techniques, and verified using 3D model of a real fragment. The comparison of the projected surface area values for the fragment, obtained using the CAD tools and using our model, are generally in good agreement, This method represents a step toward modeling that does not require a CFD result for estimation of the aerodynamic force of irregularly shaped bodies.

关键词： Projected area Fragments Trajectory

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