bluuebunny/crossref_metadata_2025 huggingface dataset:
Personhood of Water: Depositions of Bodies and Things in Water Contexts as a Way of Observing Agential Relationships
Authors: Fredengren Christina
Published: June 2021

This paper stems from a curiosity about relationships between water, depositions, life, death and sacrifice. It probes into how traditional binaries such as nature/culture, human/animal, alive/dead and language/reality were addressed in Irish medieval place lore,  using critical posthumanist theory to explore ways in which agential powers were not merely ascribed to the environment, but also observed and acknowledged by people in the past. It also considers how the agentialities of both artefacts and waters could have affected and made their way into human storytelling. In so doing, the paper presents a contribution from archaeology to the emerging field of environmental humanities, offering research that could entice us to sharpen our environmental sensibilities and respond to environmental change. Depositions of things and bodies in wet contexts are often understood as sacrifices made to deities located in the otherworld. However, there is plentiful evidence in archaeology and in medieval place-lore to suggest that waters were observed as being alive, as immanent beings, as more-than-human persons who could have received these depositions as gifts. This study explores how depositions would have added to and reconfigured such water-personhood in locally and regionally-situated ways, and how they may also have worked as apparatuses for paying close attention to the water environment.
Pengaruh Stabilitas Makro Ekonomi, Stabilitas Keamanan Dan Pertumbuhan Industri Strategis Terhadap Pertumbuhan Ekonomi
Authors: Saputro Guntur Eko , Meirinaldi Meirinaldi
Published: June 2021

The World Economic Forum in The Global Competitiveness Report 2016-2018, places Indonesia's competitiveness in the 41st rank of 138 countries with a Global Competitiveness index score of 4.52 on a scale of 1-7. Many factors determine the downgrade of Indonesia's competitiveness, including the low security and macroeconomic stability. The fundamental problems in economic development in Indonesia are the low level of welfare, unsustainable economic growth, and the inadequate development process of economic sectors.The research aims to find empirical evidence in the framework of developing economic theory of development regarding the influence of macroeconomic stability structures, security stability and strategic industrial growth and its impact on economic growth. This study uses an explanatory method which aims to explain the causal relationship and test the hypothesis (hypothesis testing study). Secondary data in this study is the semester time series data for the period 2000-2018. The research model is formulated as a recursive linear model in the form of a Cobb-Douglas production function and analyzed using multiple linear regression analysis with the Ordinary Least Square method. The results show that security stability, strategic industrial growth, and macroeconomic stability simultaneously influence economic growth.Keywords: macroeconomic stability, security stability, strategic industrial growth and economic growth.
Strategi Aktif dan Strategi Pasif Menggunakan Analisis Teknikal Saham Aali, Tlkm, Bbri dan Bbca pada Semester 1 Tahun 2020 di Bursa Efek Indonesia (BEI)
Authors: Hartono Hartono
Published: June 2021

This study aims to see the measure between the average price of the MACD indicator with the closest average price of the shares of the company PT. Astra Agro Lestari Tbk, PT. Telkom, Bank BRI and Bank BCA. This type of research is descriptive with a quantitative approach and the sampling technique used is purposive sampling method. Based on predetermined criteria, 4 companies were obtained as samples with the code: AALI, TLKM, BBRI and BBCA. The research data analysis technique begins by recording the price of the MACD indicator using the ChartNexus Version 5 software and pairing it with the closest closing price of the stock, then testing it using the independent sample t test. The results show that there is no difference between the average price of the MACD indicator and the closest average price of shares, so that the buy and sell signals generated by the MACD indicator are accurate and can be used in stock trading. The results also found that there were market conditions (IHSG) during the study period, namely bearish conditions in the 1st semester of 2020. Keywords: IHSG, Bearish, Technical Analysis, MACD, Bluechip Stock.
Motivasi Nasabah terhadap Pembiayaan Gadai Emas di Bank Syariah Mandiri Cabang Curup
Authors: Siagian Ade Onny
Published: June 2021

The research objective is to explain the people's motivation in choosing gold pawn financing at Bank Syariah Mandiri Curup Branch Office. Everyone will love products that comply with Islamic regulations. One of the products or services provided by Bank Syariah Mandiri is pawning. The type of this research is descriptive qualitative with research subjects as staff and bank employees as well as bank customers. Data collection techniques, namely, observation, interviews, documentation and data analysis techniques, data reduction, data presentation and data verification. The results of the customer research have the motivation to choose Bank Syariah Mandiri Curup Branch because it is labeled syari'ah. Gold pawning product consumers have become a fast alternative to making ends meet. Conventional bank financing is different from syari'ah banks. They can feel this with light installments every month. Based on the principles of syari'ah, choosing a gold pawn at Bank Syariah Mandiri Curup is because it has syari'ah principles.Keywords: Motivation, Financing, Gold Pawn
Pengaruh Lingkungan Pemasaran Terhadap Pendapatan Usaha Sentra Industri Pengolahan Salak Agrina Parsalakan
Authors: Hasibuan Masnilam , Napitupulu Vince
Published: June 2021

This study aims to determine how much influence the marketing environment has on the business income of the salak agrina parsalakan processing industry center. This research uses a quantitative design, quantitative research is research that involves measuring the level of a certain feature. Quantitative research includes every type of research based on calculations, percentages, averages, and other calculations. In other words, this research uses numerical or quantity calculations.The marketing environment consists of actors and forces outside of marketing that influence the ability of marketing management to build and maintain successful relationships with target customers. Income arising from the sale of merchandise, products or services within a certain period in the framework of activities for or which are the main objectives of the company which are directly related to the main business (operations) of the company concerned. The purpose of this study was to determine the effect of the marketing environment on income at the industrial processing center of Salak Agrina Parsalakan. The sample in this study were 20 customers of the Salak Agrina Parsalakan Processing Industry Center. The data collection techniques used were interviews, questionnaires and documentation studies. Testing the results of the analysis partially obtained a positive and significant value as indicated by the t test where the t value is 2.973, while the value of the t table is 1.734 so the t value is greater than the t table or 2.973> 1.734 using a significant level of 5% and df (degree of freedom) = n - 2, namely 20-2 = 18. Based on the results of the analysis, it can be seen that the marketing environment will affect income, which shows a positive and significant value, the coefficient of determination is 32.9%. while the rest is influenced by factors not examined by the authors of 67.1%. 973> 1,734 using a significant level of 5% and df (degree of freedom) = n - 2, namely 20-2 = 18. Based on the results of the analysis, it can be seen that the marketing environment will affect income shows a positive and significant value, the coefficient of determination is 32 , 9%. while the rest is influenced by factors not examined by the authors of 67.1%. 973> 1,734 using a significant level of 5% and df (degree of freedom) = n - 2, namely 20-2 = 18. Based on the results of the analysis, it can be seen that the marketing environment will affect income shows a positive and significant value, the coefficient of determination is 32 , 9%. while the rest is influenced by factors not examined by the authors of 67.1%.Keywords: Marketing Environment, Income.
Biyoteknolojide Biyosensör ve Biyoçip Uygulamaları
Authors: TÜYLEK Zülfü
Published: June 2021

Biyosensörler esas itibarıyla, bir biyo algılama materyali ve bir transdüser içerir. Biyolojik ve kimyasal etken maddelerin tespitinde kullanılır. Enzimler, antikorlar, nükleik asit çalışmaları, hücreler, dokular ve organelleri içeren biyolojik algılama malzemeleri, elektrokimyasal, optik, piezoelektrik, termal ve manyetik cihazlar gibi hedef analitleri ve transdüserleri seçici olarak tespit edebilir ve nicel olarak görüntüleyebilir. Biyoçipler, biyolojik olarak kullanılabilen mikroişlemciler olarak tanımlanır. Bir biyoçip, ultraminyatürize test tüpleri seti olarak algılanabilir. Bu sistem pek çok testin aynı anda ve çok hızlı bir biçimde yapılabilmesine imkân sağlar. Biyoçip aynı zamanda, bir numuneden birçok farklı bölgeye bakabilme avantajı da sunar. Son yıllarda biyomedikal uygulamalarında biyosensör ve biyoçipler sıklıkla tercih edilmektedir. Çünkü biyosensörler ve biyoçipler hastalıkların erken tanısında ve yaşam kalitesinin yükseltilmesinde önemli bir yere sahiptir. Nanoteknoloji veya chip teknolojisi kullanılarak geliştirilen yeni nesil biyosensörler, sonuçların daha kolay izlenmesi ve değerlendirilmesini sağlamaktadır. İnsanlar atomları anlamaya, atomları yeniden düzenlemeye, birçok yapıyı atomik (mikro, nano vb. Ölçeklere) boyutlara indirgemeye çalışırken birçok icat ortaya çıkmıştır. Bunlardan biri şüphesiz MEMS teknolojisidir.

Bu çalışmada, biyosensör ve biyoçip uygulamaları üzerine yapılan çalışmalar incelenmiştir. Yeni teknolojinin kullanım alanları araştırılmıştır. Biyosensör ve biyoçip alanında yapılan uygulamalar incelenmiştir.
Potential biomarkers for lung adenocarcinoma identified by integrative transcriptomics analysis
Authors: KASAVİ Ceyda
Published: June 2021

Lung cancer is one of the most occurring and death-causing cancers worldwide. Despite the progress, survival rate is still low due to the late diagnosis. The aim of this study is to develop a computational framework to identify potential prognostic biomarkers for lung adenocarcinoma (LUAD). Gene expression profiles obtained from three independent studies were analyzed to find differentially expressed genes (DEGs) in LUAD. Disease-specific protein-protein interaction (PPI) network was constructed among common DEGs and hub proteins were identified. Gene expression data was integrated with the human transcriptional regulatory network (TRN) to identify key regulatory elements and construct disease-specific TRN. Hub proteins that were also present in TRN of LUAD were considered as potential biomarkers and assessed by survival analysis. AURKA, CAV1, CLU, ENO1, FHL1, FHL2, LMO2, MYH11, NME1 and SFN were discovered as biomarkers for LUAD and survival analysis not only indicated their significant prognostic performance as a group but also revealed their contribution to the discrimination of risk groups. Our findings suggested that identified biomarkers could be valuable in LUAD progression and they should be considered for further experimentation.
Spatially Resolved Chandra Spectroscopy of the Large Magellanic Cloud Supernova Remnant N132D
Authors: Sharda Piyush , Gaetz Terrance J. , Kashyap Vinay L. , Plucinsky Paul P.
Published: June 2021

We perform detailed spectroscopy of the X-ray-brightest supernova remnant in the Large Magellanic Cloud (LMC), N132D, using Chandra archival observations. By analyzing the spectra of the entire well-defined rim, we determine the mean abundances for O, Ne, Mg, Si, S, and Fe for the local LMC environment. We find evidence of enhanced O on the northwestern and S on the northeastern blast wave. By analyzing spectra interior to the remnant, we confirm the presence of a Si-rich, relatively hot plasma (≳1.5 keV) that is also responsible for the Fe K emission. Chandra images show that the Fe K emission is distributed throughout the interior of the southern half of the remnant but does not extend out to the blast wave. We estimate the progenitor mass to be 15 ± 5 M
⊙ using abundance ratios in different regions that collectively cover a large fraction of the remnant, as well as from the radius of the forward shock compared with models of an explosion in a cavity created by stellar winds. We fit ionizing and recombining plasma models to the Fe K emission and find that the current data cannot distinguish between the two, so the origin of the high-temperature plasma remains uncertain. Our analysis is consistent with N132D being the result of a core-collapse supernova in a cavity created by its intermediate-mass progenitor.
GASP. XXXIII. The Ability of Spatially Resolved Data to Distinguish among the Different Physical Mechanisms Affecting Galaxies in Low-density Environments
Authors: Vulcani Benedetta , Poggianti Bianca M. , Moretti Alessia , Franchetto Andrea , Bacchini Cecilia , McGee Sean , Jaffé Yara L. , Mingozzi Matilde , Werle Ariel , Tomičić Neven , Fritz Jacopo , Bettoni Daniela , Wolter Anna , Gullieuszik Marco
Published: June 2021

Galaxies inhabit a wide range of environments and therefore are affected by different physical mechanisms. Spatially resolved maps combined with the knowledge of the hosting environment are very powerful for classifying galaxies by physical process. In the context of the GAs Stripping Phenomena in galaxies (GASP), we present a study of 27 non-cluster galaxies: 24 of them were selected for showing asymmetries and disturbances in the optical morphology, suggestive of gas stripping; 3 of them are passive galaxies and were included to characterize the final stages of galaxy evolution. We therefore provide a panorama of the different processes taking place in low-density environments. The analysis of VLT/MUSE data allows us to separate galaxies into the following categories: galaxy–galaxy interactions (2 galaxies), mergers (6), ram pressure stripping (4), cosmic web stripping (2), cosmic web enhancement (5), gas accretion (3), and starvation (3). In one galaxy we identify the combination of merger and ram pressure stripping. Only 6/27 of these galaxies have just a tentative classification. We then investigate where these galaxies are located on scaling relations determined for a sample of undisturbed galaxies. Our analysis shows the successes and limitations of a visual optical selection in identifying the processes that deplete galaxies of their gas content and probes the power of IFU data in pinning down the acting mechanism.
Microscale Processes Determining Macroscale Evolution of Magnetic Flux Tubes along Earth’s Magnetopause
Authors: Hwang K.-J. , Burch J. L. , Russell C. T. , Choi E. , Dokgo K. , Fear R. C. , Fuselier S. A. , Petrinec S. M. , Sibeck D. G. , Hasegawa H. , Fu H. , Øieroset M. , Escoubet C. P. , Giles B. L. , Khotyaintsev Y. , Graham D. B. , Gershman D. J. , Pollock C. J. , Ergun R. E. , Torbert R. B. , Broll J.
Published: June 2021

An important process affecting solar wind–Earth’s magnetosphere coupling is nonsteady dayside magnetic reconnection, observationally evidenced by a flux transfer event (FTE) that shows a bipolar variation of the magnetic field component normal to the magnetopause. FTEs often consist of two interlinked flux tubes, but, local kinetic processes between the flux tubes are not understood in the context of the FTE structuring, evolution, and impact. An FTE observed by the Magnetospheric Multiscale mission on 2017 December 18 consisted of two flux tubes of different topology. One includes field lines with ends connected to the northern and southern hemispheres while the other includes field lines with both ends connected to the magnetosheath. Reconnection occurring at the flux-tube interface indicates how interacting flux tubes evolve into a flux rope with helical magnetic topology that is either closed or open. This study demonstrates a new aspect of how micro- to meso-scale dynamics occurring within FTEs determines their macroscale characteristics and evolution.
Thermonuclear Explosions and Accretion-induced Collapses of White Dwarfs in Active Galactic Nucleus Accretion Disks
Authors: Zhu Jin-Ping , Yang Yuan-Pei , Zhang Bing , Liu Liang-Duan , Yu Yun-Wei , Gao He
Published: June 2021

White dwarfs (WDs) embedded in the gaseous disks of active galactic nuclei (AGNs) can rapidly accrete materials from these disks and grow in mass to reach, or even exceed, the Chandrasekhar limit. Binary WD (BWD) mergers are also believed to occur in AGN accretion disks. We study observational signatures from these events. We suggest that mass-accreting WDs and BWD mergers in AGN disks can lead to thermonuclear explosions that drive an ejecta shock breakout from the disk surface and power a slow-rising, relatively dim Type Ia supernova (SN). It is possible that such SNe Ia may be outshone by the emission of the AGN disk around a supermassive black hole (BH) with a mass of M
SMBH ≳ 108
M
⊙. In addition, accretion-induced collapses (AICs) of WDs in AGN disks may sometimes occur, which may form highly magnetized millisecond neutron stars (NSs). The subsequent spindown process of this nascent magnetar can deposit its rotational energy into the disk materials, resulting in a magnetar-driven shock breakout and a luminous magnetar-powered transient. We show that such an AIC event could power a rapidly evolving and luminous transient for a magnetic field of B ∼ 1015 G. The rising time and peak luminosity of the transient, powered by a magnetar with B ∼ 1014 G, are predicted to have similar properties to those of superluminous SNe. AIC events taking place in the inner parts of disks around relatively less massive supermassive BHs (M
SMBH ≲ 108
M
⊙) are more likely to power transients that are much brighter than the AGN disk emission, and hence easily identified.
Uranus’s Hidden Narrow Rings
Authors: Hedman Matthew , Chancia Rob
Published: June 2021

In addition to its suite of narrow dense rings, Uranus is surrounded by an extremely complex system of dusty rings that were most clearly seen by the Voyager spacecraft after it flew past the planet. A new analysis of the highest-resolution images of these dusty rings reveals that a number of them are less than 20 km wide. The extreme narrowness of these rings, along with the fact that most of them do not appear to fall close to known satellite resonances, should provide new insights into the forces responsible for sculpting the Uranian ring system.
Group structure of Guiana dolphins, Sotalia guianensis (Cetacea, Delphinidae) in Ilha Grande Bay, Rio de Janeiro, southeastern Brazil
Authors: Tardin Rodrigo , Galvão Carine , Espécie Mariana , Simão Sheila
Published: June 2021

Cetaceans present a group structure of great complexity and display a wide behavioral plasticity. Many efforts have been made to understand the group structures of the various species, however, this type of information is still lacking for some species. Therefore, our objectives were to 1) characterize the structure of the Sotalia guianensis groups in Ilha Grande Bay, Rio de Janeiro, Brazil, and 2) investigate how both behavior and season influence the group structure of this population. This species is considered “data deficient” by the IUCN. We conducted 28 boat trips using group focal procedures, and a total of 1,314 groups were observed. Of these groups, 1,268 (94.4%) contained calves, the largest percentage ever reported for the species. Groups with calves were larger than those without them, suggesting a strategy to protect these individuals with underdeveloped physiology. The mean group sizes reached 17.6 ± 18.3 individuals. Within these groups, we observed that both behavior (H = 112.5, d.f. = 2, P < 0.05) and season (number of simulations: 10,000; sample size of fall-winter = 544; sample size of spring-summer = 684; P < 0.05), demonstrated a statistically significant influence. The most common degree of cohesion was mixed, and cohesion also varied with behavior (χ² = 10.1, P < 0.05) and season (χ² = 31.0, P < 0.05). This paper contributes towards understanding the highly variable nature of S. guianensis group dynamics. These data may be important in understanding the structure of groups in a site that is being increasingly impacted by different human activities. Moreover, this area contains the largest aggregation ever observed for this species and may therefore represent an important source of genetic diversity for the species as a whole.
Spatio-temporal variation in surf zone fish communities at Ilha do Cardoso State Park, São Paulo, Brazil
Authors: Menegassi del Favero Jana , Ferraz Dias June
Published: June 2021

In order to analyze the time-space variation of the fish fauna in the surf zone fish communities at Ilha do Cardoso State Park, São Paulo, Brazil, four consecutive hauls were done over a year on three beaches with different degrees of exposure, at low and high tide. To evaluate the influence of each abiotic variable over the fish community, a Canonical Correspondence Analysis was conducted. We identified 7,286 individuals belonging to 20 families and 47 species, most specimens collected were juveniles. At low tide, the highest diversity and richness values were calculated while the highest dominance was obtained at high tide. As for the number of species collected at the three beaches, stood out for the lower values the cooler months, between June and September. Abiotic variables explained 41.3% of the variability of biological data, where 11.4% corresponds to the spatial variation. Meanwhile the temporal variables accounted for 31.9% of the variation in abundance, where 26.3% of the variance explained nycthemeral variation. Additionally two groups were clearly observed between months with low and high temperature. However in this variable, the tidal variation, excluding the seasonal effect, explained 6.2%, while seasonality, excluding tide effect, explained 26.3%. Although the main measurable seasonal changes were related to temperature, water temperature showed a low percentage of explanation in the fish fauna variability (2.7%). Finally, it is emphasized that the seasonal changes in surf zone fish community primarily reflect patterns of recruitment determined by the reproductive activity and coastal circulation.
Zoning of the Mejillones Peninsula marine protected coastal area of multiple uses, northern Chile
Authors: Ulloa Raúl , Vargas Adolfo , Hudson Cristian , Rivadeneira Marcelo M.
Published: June 2021

Marine protected areas of multiple uses (MPA-MU), are an important management tool to protect biodiversity and regulate the use of coastal marine resources. However, robust conservation plans require an explicit consideration of not only biological but also social components, balancing the protection of biodiversity with a sustainable exploitation of marine resources. Here we applied the decision-making algorithm MARXAN to provide a zoning analysis at the Mejillones Peninsula MPA-MU in northern Chile, one of largest MPA’s of the Humboldt Current Marine Ecosystem. We set conservation goals for coarse and fine-filter conservation targets that were crossed out against different threats and pressure factors from human activities across the area. We identified a portfolio of sites for conservation, within the Mejillones Peninsula MPA-MU, representing different ecological systems with different levels of human impacts and vulnerability. These results may serve as a foundational guideline for the future administration of the MPA-MU.
Diet and feeding ecology of the little tunny, Euthynnus alletteratus (Pisces: Scombridae) in the central Colombian Caribbean: changes in 18 years
Authors: Garcia Camilo B. , Posada Camila
Published: June 2021

Trophic ecology and diet of the little tunny (Euthynnus alletteratus) in central Colombian Caribbean is described. The little tunny is a pelagic top predator but not a voracious fish (trophic level of 4.49, Q/B of 10.8). Its diet seems impoverished when compared with a study conducted in 1986 in the same general location and with studies in other locations. Moreover, the main diet item has changed, new items have appeared and other have disappeared in the time interval between 1986 and the present study (2003/2004, 18 years). Lack of monitoring of pelagic fish populations precludes the identification of tendencies but a regime change hypothesis is worth investigating. The little tunny eats more in the dry season than in the rainy season and diet items change with seasons in line with findings of other studies that signal correlations between seasons and diet. Likewise, local little tunny eats more in the afternoon than in the morning which suggests it eats in daylight not in the night contrary to what has been found in studies somewhere else.
New records of Lolliguncula (Lolliguncula) argus Brakoniecki & Roper, 1985 (Myopsida: Loliginidae) in northwestern Mexico
Authors: Granados-Amores Jasmín , Hochberg Frederick G. , Salinas-Zavala César A.
Published: June 2021

Seven specimens of Lolliguncula (Lolliguncula) argus, were collected in the shrimp fisheries of the Gulf of California and five specimens from the western coast of Baja California Peninsula, deposited in the Santa Barbara Museum of Natural History (USA), are examined and reported. These records expand species geographic distribution range for approximately 950 km and report the maximum size of mantle length 38.8 mm for males and 60.8 mm for females. Morphometric data of the 12 collected specimens are presented, and species funnel organ and statoliths are described.
Abundance, distribution, feeding habits and trophic interactions in five flatfish species (Pleuronectiformes) in the Mexican central Pacific
Authors: Flores-Ortega Juan R. , Godínez-Domínguez Enrique , González-Sansón Gaspar , Rojo-Vázquez Jorge A. , López-Prado Antonio C. , Morales-Jauregui María Y.
Published: June 2021

We analyzed the spatial distribution patterns of the five most abundant flatfish species caught by shrimp trawl nets on the continental shelf of the Mexican central Pacific. Food diets and trophic interactions between of the flatfish species are described as well. Flatfishes are distributed between 20 and 60 m depth. Bothus leopardinus showed the greatest abundance during the cold season (January-May), the other species did not show significant differences between seasons (cold and warm). The diet of the flatfish species consist of crustaceans, fishes and cephalopods. B. leopardinus and Syacium ovale are consumers of crustaceans, such as crabs, shrimps and stomatopods. Cyclopsetta panamensis, C. querna and Monolene assaedae based their diet in fishes and cephalopods. The feeding strategy of the five species analyzed is considered to be generalist, consuming a high number of preys in both seasons. Between the flatfish species, low values of overlapping in the diets were observed in size class and periods of the year. The flatfish species consume the available food resources and could change the preys consumed, according to prey availability, to avoid intra and interspecific competition.
A bio-economic approach to analyze the role of alternative seeding-harvesting schedules, water quality, stocking density and duration of cultivation in semi-intensive production of shrimp in Mexico
Authors: Estrada-Pérez Margarita , Ruiz-Velazco Javier M.J. , Hernandez-Llamas Alfredo , Zavala-Leal Iram
Published: June 2021

We used a bio-economic model to analyze the role that alternative seeding-harvesting schedules, temperature, dissolved oxygen, stocking density, and duration of cultivation play in the economic performance of semi-intensive shrimp cultivation in Mexico. The highest production was predicted for the May-August schedule (1130-2300 kg ha-1), while the lowest yields were obtained for the March-June schedule (949-1300 kg ha-1). The highest net revenues were projected for the August-November schedule (US$354-1444 ha-1), while the lowest was projected for the May-August schedule (US$330-923 ha-1). The highest annual net revenues were predicted for the combination of the March-June and August-November schedules (US$1432-2562 ha-1). Sensitivity analysis indicated temperature and dissolved oxygen were the most important factors determining net revenues in March-June schedule. For the May-August and August-November schedules, stocking density was the most important factor. Duration of cultivation was the least sensitive variable. Break-even production analysis confirmed that the combination of the March-June and August-November schedules were more efficient from an economic perspective. We recommend test some ponds with higher stocking density in the March-June and August-November schedules, and in the latter case, seeding in June or July rather than August.
Parasite burden in decapod crustaceans from the central coast of Chile: is there any association with the relationship with definitive host abundances?
Authors: Leiva Natalia , George-Nascimento Mario , Muñoz Gabriela
Published: June 2021

Crustaceans play an important role in parasite life cycles, serving as second intermediate hosts. However, there are scarce parasitological studies in crustaceans from the rocky intertidal habitats, in Chile and around de world. In this study we aimed to record the parasites in decapod crustaceans, compare their parasitic loads between localities and relate them with the abundance of the definitive hosts (fishes and birds). Between July and September 2013, 409 crustacean specimens, corresponding to 16 species, were collected from the rocky intertidal zone of two localities of central Chile (33°S), Las Cruces and Montemar. Of out the sample, 65.5% was parasitized; counting 2,410 metacercariae and 18 nematodes. One group of these metacercariae belonged to the family Opecoelidae; while others corresponded to the family Microphallidae. Nematodes belonged to the family Cystidicolidae. The highest prevalence and abundance of opecoelids were in P. violaceus (96.9%, 13.59 ± 17.50 parasites/crustacean), microphallids were mostly recorded in the crab Petrolisthes tuberculosus (42.3%, 11.08 ± 4.8 parasites/crustacean), while cystidicolids were less prevalent and abundant than digenean at both localities. Parasite loads was affected by body size, locality and species of crustacean hosts. No association was found between parasite loads in these intermediate hosts and the abundance of definitive hosts. The low relationships between parasite loads and host abundances may be due to several reasons, such as a wide trophic spectrum and great capacity of movement, which would not contribute to the parasite transmission and the direct relationship with the definitive host abundances.
Inclusion of copepod Acartia tonsa nauplii in the feeding of Centropomus undecimalis larvae increases stress resistance
Authors: De Melo-Costa Wanessa , Vaz Avelar de Carvalho Cristina , Passini Gabriel , Teles Andressa , Sozo-Cecchini Manuela , Ronzani-Cerqueira Vinicius
Published: June 2021

This research represents the first result of studies of the common snook Centropomus undecimalis larvae from broodstock matured in captivity in Brazil. The aim of this study was to evaluate if the inclusion of Acartia tonsa nauplii improves stress resistance of common snook larvae. The larvae were fed with: rotifers Brachionus plicatilis (10 to 15 mL-1); A. tonsa nauplii (0.25 to 0.5 mL-1) and rotifers (5 to 7.5 mL-1), and A. tonsa nauplii (0.12 to 0.25 mL-1). The average percentage of survival of the treatments was 11.9%. At 20 days of age, larvae were subjected to thermal stress. Subsequently, the stress resistance was evaluated. Common snook larvae fed B. plicatilis+A. tonsa reached a higher weight and length (7.5 ± 0.00 mg and 9.1 ± 0.23 mm, respectively) and resisted more heat stress (87.4%) than larvae fed other foods, indicating that the feed mixture is satisfactory as a starter diet for larvae of common snook. However, more research is needed to confirm these results.
Isolation and risk assessment of Geotrichum spp. in the white shrimp (Litopenaeus vannamei Boone, 1931) from culture ponds
Authors: Ochoa José Luis , Ochoa-Alvarez Norma , Guzmán-Murillo Maria Antonia , Hernandez Sergio , Ascencio Felipe
Published: June 2021

The present study was done in order to identify the fungus invading some of the supralittoral ponds used for shrimp aquaculture in the CIBNOR facilities in La Paz, Baja California Sur (BCS), México during the summer season. From the walls and bottoms of the ponds, two strains of Geotrichum spp. were isolated and morphologically identified. Fungal adhesion towards hemocytes and primary cultures of various white shrimp (Litopeneaus vannamei) tissues (gill, tegument, and gut) was analyzed to determine infectivity. Extracellular protease, lipase, and amylase activity were evaluated as virulence factors. Survival of shrimp postlarvae (PL8) exposed to fungal culture supernatant or to their filaments was also investigated. The results showed that shrimp tegument cells and hemocytes were very susceptible to Geotrichum spp. invasion, and that this fungus provokes great mortality of post-larvae. Hence, Geotrichum spp. could be considered an opportunistic pathogen that might represent a serious health risk to shrimp in culture.
Periphytic and planktonic bacterial community structure in turbid and clear shallow lakes of the Pampean Plain (Argentina): a CARD-FISH approach
Authors: Sánchez Laura María , Schiaffino María Romina , Pizarro Haydée , Izaguirre Irina
Published: June 2021

Bacterioplankton and bacterioperiphyton composition was analyzed using the CARD-FISH technique in three shallow lakes of the Pampean Plain (Argentina) with contrasting regimes: clear vegetated, turbid due to phytoplankton and turbid inorganic, due to inorganic particles. We postulated that these differences would influence the proportion of the main bacterial groups both in periphyton and in plankton. The turbid lake due to phytoplankton presented the highest total abundances in both communities. Alphaproteobacteria was the dominant group in the three lakes in both communities. Redundancy analysis (RDA) evidenced that the bacterioplankton structure was different among lakes and mainly influenced by dissolved inorganic nitrogen and conductivity. On the other hand, for the bacterioperiphyton, RDA showed that bacterial group abundances increased with higher periphytic chlorophyll-a values. In the clear lake the relative abundance of Betaproteobacteria and Cytophaga increased in the bacterioperiphyton towards the end of the colonization. Our study suggests that the lake regime (clear or turbid) influence the structure of bacterioplankton and bacterioperiphyton.
Oceanic and climatic drivers of mangrove changes in the Gulf of Urabá, Colombian Caribbean
Authors: Suárez July A. , Urrego Ligia E. , Osorio Andrés , Ruiz Hiara Y.
Published: June 2021

The Gulf of Uraba is the largest estuary on the Caribbean coast of Colombia. The aim of this research was to analyse the oceanic, climatic and environmental variables that influence mangrove structure and composition in the gulf. Based on the availability of remote sensing, the study area was divided into western and eastern zones. The spatial pattern of environmental variables (water salinity, pH and percentage of organic matter, sand, silt and clay in the soils) and oceanic and climatic variables (winds, wave height and wave period) was analysed. The relationship of these variables with variables of vegetation structure (basal area, diameter at breast height, tree height, and abundance of seedlings of mangrove species in 1 m2 subplots) was analysed in 27 plots of 500 m2 containing fringe mangroves and 5 plots containing basin mangroves. Mangroves of the western zone showed a higher structural development and were dominated by Rhizophora mangle (red mangrove). This zone is supplied by fresh water and sediments, and the soils have a high content of organic matter and clay and a low degree of anthropogenic disturbance. The eastern zone was characterized by higher pore water salinity due to lower freshwater input from rivers. In this area there is a smaller impact of waves and winds, higher sedimentation rates, high anthropogenic disturbance and mangroves are dominated by Avicennia germinans (black mangrove). Although Laguncularia racemosa (white mangrove) did not show a particular spatial pattern, due to its tolerance to open canopy conditions it was commonly found in anthropogenically disturbed areas.
Soundscape of a management and exploitation area of benthic resources in central Chile
Authors: Borie Alfredo , Bezerra Natalia P.A. , Klarian Sebastian A.L. , Travassos Paulo
Published: June 2021

Acoustic ecology is an emerging and poorly known field of research. Soundscape has been used to infer the behavior of several species in different environments and can serve as a reliable indicator of the habitat type and quality; also, it is believed that it is an important factor for larvae orientation in settlement areas. We used the passive acoustic method to evaluate the soundscape of a management and exploitation area of benthic resources, a rocky reef area in central Chile. It was possible to hear a continuous cracking sound during recording and underwater observations. We detected two distinct frequency bands with similar parameters during the night and day, a band between 90 and 300 Hz, which corresponded to the effects of sea waves (geophony), and a frequency band with a range of 1,500 to 2,700 Hz (biophony), with a fundamental frequency of 2,070 Hz. Both bands had similar energy (~88.0 dB re: 1V/µPa). These results show the relevant acoustic activity in the area, which may have important ecological implications for the recruitment of commercially important benthic resources.
Taxonomic distinctness of soft-bottoms mollusks from Gulf of Batabanó, Cuba
Authors: Tripp-Quezada Arturo , Villalejo-Fuerte Marcial Trinidad , Capetillo-Piñar Norberto
Published: June 2021

Taxonomic distinction is a measure of diversity that has a number of advantages that provides relevant connotation to theoretical and applied ecology. The usefulness of this type of measure as an alternative method for assessing the biodiversity of soft-bottom benthic marine ecosystems was tested using the indices of average taxonomic distinctness (Delta+) and variation in taxonomic distinctness (Lambda+) for mollusk communities of the Gulf of Batabanó (Cuba). For this purpose, inventories of soft bottom benthic mollusk species obtained in the period 1981-1985 and the years 2004/2007 were used. Both species lists were analyzed and compared at spatial and temporal scales. The taxonomic composition, between the period 1981-1985 and years 2004 and 2007, consisted of 3 classes, 20 orders, 60 families, 137 genera and 182 species observed. With the exception of the class level, a non-significant decrease of this composition in 2004 and 2007 was detected. At a spatial scale, a significant decrease in the taxonomic richness was observed in 2004. Significant differences were not detected in Delta+ and Lambda+ to time scale, but at spatial scale, results revealed significant differences that could be attributed to the combined effect of increased anthropogenic activities in the region with hurricane induced effects. These results suggest that the pair of indices, Delta+ and Lambda+, are good descriptors of the biodiversity of soft-bottom benthic mollusk communities in the Gulf of Batabanó.
Implementation of the Ramsar strategic plan in coastal wetlands of the Península de Yucatán: regulations and normativity
Authors: Vidal Laura , Vallarino Adriana , Benítez Ileana , Correa Jorge
Published: June 2021

The way how Mexico applies the normative and other management strategies, regarding coastal wetland and wetlands birds conservation of the Península de Yucatán following the Ramsar Strategic Plan 2009- 2015 is analyzed. Regulatory criteria within Management Programs of Natural Protected Areas and Ecologic Ordinance Instruments were analyzed identifying strengths and weaknesses under an ecological integrity concept. Results show the need to homogenize the concept of integrity within regulation, to develop a hierarchical spatial structure for management strategies. It will: a) promotes connectivity, b) strength the perception of buffer zones and critical habitats, c) emphasize in the protection of biologic heterogeneity in space and time, ecological processes and trophic networks and, develop regulation about wetland restoration. We conclude that current normative framework is still very inefficient and a systemic vision is required to protect these ecosystems. Nine suggestions to improve the current scenario are included.
The effect of different feeding and starvation frequencies on growth utilization and nutrients, for Piaractus brachypomus (Cuvier, 1818)
Authors: Gómez-Peñaranda Jose , Vásquez-Gamboa Lucena , Valencia Diego
Published: June 2021

A possible practical use of compensatory growth, subjecting Piaractus brachypomus at different weekly feeding and fasting frequencies was sought. For this purpose, 450 individuals with an initial average weight of 20 g, arranged in five treatments with three replicates, were used. T1 = feed to satiation 5 days and fasting for two days; T2 = feed to satiation 6 days and fasting one day; T3 = feed to satiation 7 days; T4 = fasting 14 days and subsequent feedback to satiety and T5 = power following the manufacturer's recommended food tables. Individuals of T1 treatment had the final weight and instantaneous growth rate lowest results compared to T2 and T3. This meant that fast two days a week influenced growth negatively, but the one-day fast (T2), did not affect it. The daily highest feeding rate was present with treatment T4 but only relative to T3 and T5, due to a voluntary increase in food intake after the fasting period. By contrast, there were no differences between the T1, T2 and T3, which indicate that individuals of T1 and T2 treatments, voluntarily increased intake after fasting days equaling intake T3 treatment. The body composition of the fish was not affected by the treatments, so that after refeeding, all reserves used during fasting were restored. The values of protein and energy retention were better with treatment T5, because it used less food and its growth was similar to the other treatments. These results indicated that feeding could be deleted in one day but increasing ration during the rest of the week. However, the T5 results are relevant to the cultivation of the species, since the production cost of each kilogram is low and net profit is higher.
Study of macroinvertebrate in two intertidal soft bottoms: reference data in conditions of incipient anthropic impact
Authors: Crespi-Abril Augusto César , Ferrando Agustina , Dileo Agostino-Andrea Matías Emanuel
Published: June 2021

In this study, we analyzed the relation between the abundance of benthic macroinvertebrates and relevant environmental variables in two intertidal in Golfo Nuevo (Argentinean patagonia), one near a urban center (Mimosa Beach, PM) and the other at 20 km from that location (Cerro Avanzado Beach, CA). Within each beach, the environmental conditions were homogeneous (90% of similarity). Mean size grain values, anoxic layer depth, and percent organic matter were 117.6 µm, 4.95 cm and 0.76%, and 165.2 µm, 9.5 cm and 0.63%, for PM and CA respectively. Even though three families were the most abundant in both beaches (Tellinidae, Maldanidae and Opheliidae), nine families were exclusively observed in PM. This resulted in a higher biodiversity in PM (3.06) in relation to CA (1.77). When faunal composition was considered, the similarity between sites was notably low (lower than 82%) if compared with the environmental conditions. Granulometry and organic matter were the variables with the highest correlation with macroinvertebrates abundance. This is the first study of macroinvertebrates and their relationship with some environmental variables throughout the complete spatial extension of two beaches in Golfo Nuevo. This is of particular relevance if we consider that coastal regions of this gulf has been exposed to a sustained increase of anthropic activities in the last years and base- line information is scarce.
Stress response in transport of juvenile cobia Rachycentron canadum using the anesthetic benzocaine
Authors: Pedron Janaína S. , Miron Denise S. , Rodrigues Ricardo V. , Okamoto Marcelo H. , Tesser Marcelo B. , Sampaio Luís A.
Published: June 2021

This experiment evaluated the efficacy of benzocaine to reduce stress response during transport of juvenile cobia. Fish (30 g) were packed in bags and transported for 8 h (stocking density = 10 g L-1). Three concentrations of benzocaine were evaluated: 0, 2, and 6 mg L-1. Blood samples were taken for glucose and hematocrit before transportation, and then at 0, 2, 24, and 48 h after. Water quality parameters were verified. No mortality was observed. Total ammonia nitrogen was higher (2.46 mg L-1) and pH was lower (6.92) at 2 mg benzocaine L-1. There was an increase in blood glucose for all treatments on arrival, and it was higher for those exposed to benzocaine at 6 mg L-1, although at 48 h they were all similar. The hematocrit did not differ among treatments. The results suggest: 1) the density 10 g L-1 is considered safe for juvenile cobia transport; 2) benzocaine did not mitigate stress response on cobia during transport, therefore its use is not recommended for this purpose.
AnthropogenicSusceptibility to environmental variability of the aquaculture sector in the State of Colima, Mexico: case study
Authors: Liñan-Cabello Marco Agustin , Quintanilla-Montoya Ana Luz , Sepúlveda-Quiroz Cesar , Cervantes-Rosas Omar D.
Published: June 2021

In Mexico, as in many other Latin American countries, the lack of a development plan and/or prevention in aquaculture to environmental variability is evident. In the State of Colima, aquaculture presents lags in terms of technical and productive capacity especially for growing tilapia Oreochromis spp. Surveys were performed to farmers and experts, in addition to consulting scientific literature sources, and identifying different risk factors arising from the practice of aquaculture in order to assess the vulnerability of the sector. The main risk factor associated with hydrometeorological phenomena, for which the need to define high-risk areas, even more, given the uncertainty of the same due to global climate change is recognized. This study proposes to implement a comprehensive program of technological conversion and control measures for alien species that also consider aquaculture production schemes based on the efficient use of water, and to consider using this endemic species for cultivation.
Eyeless morphotype in the southern stingray (Dasyatis americana): a non-lethal and frequent abnormality from the southern Gulf of Mexico
Authors: Mendoza-Carranza Manuel , Santiago-Alarcón Diego , Pérez-Jiménez Juan Carlos , Hernández-Lazo Chrystian Carolina
Published: June 2021

Elasmobranchs are active predators that depend on a highly developed visual system. The eyes of the southern stingray, Dasyatis americana, are adapted to a changing light environment in coastal zones. In this study we use morphological characters and molecular methods (mtDNA COI) to describe an eyeless morphotype of D. americana from six individuals collected from commercial small-scale fisheries on the Campeche Bank (southern Gulf of Mexico). Additionally to the eyeless characteristic, both regular (presence of eye) and eyeless (absence of eye) morphotypes have contrasting quantitative values and qualitative features for different phenotypic traits (color, teeth number, pelvic fin and spiracle form). Mature female and male eyeless morphotype had functional internal reproductive structures. Using the bar code gene, we found conclusive evidence that the eyeless morphotype belongs to the species D. americana. This is the first report on reproductively functional eyeless individuals of this species or close relatives elsewhere, which live sympatrically with regular D. americana individuals in the southern Gulf of Mexico